1	//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===//
2	//
3	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4	// See https://llvm.org/LICENSE.txt for license information.
5	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6	//
7	//===----------------------------------------------------------------------===//
8	//
9	// This file implements semantic analysis for expressions.
10	//
11	//===----------------------------------------------------------------------===//
12
13	#include "TreeTransform.h"
14	#include "UsedDeclVisitor.h"
15	#include "clang/AST/ASTConsumer.h"
16	#include "clang/AST/ASTContext.h"
17	#include "clang/AST/ASTLambda.h"
18	#include "clang/AST/ASTMutationListener.h"
19	#include "clang/AST/CXXInheritance.h"
20	#include "clang/AST/DeclObjC.h"
21	#include "clang/AST/DeclTemplate.h"
22	#include "clang/AST/EvaluatedExprVisitor.h"
23	#include "clang/AST/Expr.h"
24	#include "clang/AST/ExprCXX.h"
25	#include "clang/AST/ExprObjC.h"
26	#include "clang/AST/ExprOpenMP.h"
27	#include "clang/AST/OperationKinds.h"
28	#include "clang/AST/ParentMapContext.h"
29	#include "clang/AST/RecursiveASTVisitor.h"
30	#include "clang/AST/Type.h"
31	#include "clang/AST/TypeLoc.h"
32	#include "clang/Basic/Builtins.h"
33	#include "clang/Basic/DiagnosticSema.h"
34	#include "clang/Basic/PartialDiagnostic.h"
35	#include "clang/Basic/SourceManager.h"
36	#include "clang/Basic/Specifiers.h"
37	#include "clang/Basic/TargetInfo.h"
38	#include "clang/Basic/TypeTraits.h"
39	#include "clang/Lex/LiteralSupport.h"
40	#include "clang/Lex/Preprocessor.h"
41	#include "clang/Sema/AnalysisBasedWarnings.h"
42	#include "clang/Sema/DeclSpec.h"
43	#include "clang/Sema/DelayedDiagnostic.h"
44	#include "clang/Sema/Designator.h"
45	#include "clang/Sema/EnterExpressionEvaluationContext.h"
46	#include "clang/Sema/Initialization.h"
47	#include "clang/Sema/Lookup.h"
48	#include "clang/Sema/Overload.h"
49	#include "clang/Sema/ParsedTemplate.h"
50	#include "clang/Sema/Scope.h"
51	#include "clang/Sema/ScopeInfo.h"
52	#include "clang/Sema/SemaFixItUtils.h"
53	#include "clang/Sema/SemaInternal.h"
54	#include "clang/Sema/Template.h"
55	#include "llvm/ADT/STLExtras.h"
56	#include "llvm/ADT/StringExtras.h"
57	#include "llvm/Support/Casting.h"
58	#include "llvm/Support/ConvertUTF.h"
59	#include "llvm/Support/SaveAndRestore.h"
60	#include "llvm/Support/TypeSize.h"
61	#include <optional>
62
63	using namespace clang;
64	using namespace sema;
65
66	/// Determine whether the use of this declaration is valid, without
67	/// emitting diagnostics.
68	bool Sema::CanUseDecl(NamedDecl *D, bool TreatUnavailableAsInvalid) {
69	// See if this is an auto-typed variable whose initializer we are parsing.
70	if (ParsingInitForAutoVars.count(D))
71	return false;
72
73	// See if this is a deleted function.
74	if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Val: D)) {
75	if (FD->isDeleted())
76	return false;
77
78	// If the function has a deduced return type, and we can't deduce it,
79	// then we can't use it either.
80	if (getLangOpts().CPlusPlus14 && FD->getReturnType()->isUndeducedType() &&
81	DeduceReturnType(FD, Loc: SourceLocation(), /*Diagnose*/ false))
82	return false;
83
84	// See if this is an aligned allocation/deallocation function that is
85	// unavailable.
86	if (TreatUnavailableAsInvalid &&
87	isUnavailableAlignedAllocationFunction(FD: *FD))
88	return false;
89	}
90
91	// See if this function is unavailable.
92	if (TreatUnavailableAsInvalid && D->getAvailability() == AR_Unavailable &&
93	cast<Decl>(Val: CurContext)->getAvailability() != AR_Unavailable)
94	return false;
95
96	if (isa<UnresolvedUsingIfExistsDecl>(Val: D))
97	return false;
98
99	return true;
100	}
101
102	static void DiagnoseUnusedOfDecl(Sema &S, NamedDecl *D, SourceLocation Loc) {
103	// Warn if this is used but marked unused.
104	if (const auto *A = D->getAttr<UnusedAttr>()) {
105	// [[maybe_unused]] should not diagnose uses, but __attribute__((unused))
106	// should diagnose them.
107	if (A->getSemanticSpelling() != UnusedAttr::CXX11_maybe_unused &&
108	A->getSemanticSpelling() != UnusedAttr::C23_maybe_unused) {
109	const Decl *DC = cast_or_null<Decl>(Val: S.getCurObjCLexicalContext());
110	if (DC && !DC->hasAttr<UnusedAttr>())
111	S.Diag(Loc, diag::warn_used_but_marked_unused) << D;
112	}
113	}
114	}
115
116	/// Emit a note explaining that this function is deleted.
117	void Sema::NoteDeletedFunction(FunctionDecl *Decl) {
118	assert(Decl && Decl->isDeleted());
119
120	if (Decl->isDefaulted()) {
121	// If the method was explicitly defaulted, point at that declaration.
122	if (!Decl->isImplicit())
123	Diag(Decl->getLocation(), diag::note_implicitly_deleted);
124
125	// Try to diagnose why this special member function was implicitly
126	// deleted. This might fail, if that reason no longer applies.
127	DiagnoseDeletedDefaultedFunction(FD: Decl);
128	return;
129	}
130
131	auto *Ctor = dyn_cast<CXXConstructorDecl>(Val: Decl);
132	if (Ctor && Ctor->isInheritingConstructor())
133	return NoteDeletedInheritingConstructor(CD: Ctor);
134
135	Diag(Decl->getLocation(), diag::note_availability_specified_here)
136	<< Decl << 1;
137	}
138
139	/// Determine whether a FunctionDecl was ever declared with an
140	/// explicit storage class.
141	static bool hasAnyExplicitStorageClass(const FunctionDecl *D) {
142	for (auto *I : D->redecls()) {
143	if (I->getStorageClass() != SC_None)
144	return true;
145	}
146	return false;
147	}
148
149	/// Check whether we're in an extern inline function and referring to a
150	/// variable or function with internal linkage (C11 6.7.4p3).
151	///
152	/// This is only a warning because we used to silently accept this code, but
153	/// in many cases it will not behave correctly. This is not enabled in C++ mode
154	/// because the restriction language is a bit weaker (C++11 [basic.def.odr]p6)
155	/// and so while there may still be user mistakes, most of the time we can't
156	/// prove that there are errors.
157	static void diagnoseUseOfInternalDeclInInlineFunction(Sema &S,
158	const NamedDecl *D,
159	SourceLocation Loc) {
160	// This is disabled under C++; there are too many ways for this to fire in
161	// contexts where the warning is a false positive, or where it is technically
162	// correct but benign.
163	if (S.getLangOpts().CPlusPlus)
164	return;
165
166	// Check if this is an inlined function or method.
167	FunctionDecl *Current = S.getCurFunctionDecl();
168	if (!Current)
169	return;
170	if (!Current->isInlined())
171	return;
172	if (!Current->isExternallyVisible())
173	return;
174
175	// Check if the decl has internal linkage.
176	if (D->getFormalLinkage() != Linkage::Internal)
177	return;
178
179	// Downgrade from ExtWarn to Extension if
180	// (1) the supposedly external inline function is in the main file,
181	// and probably won't be included anywhere else.
182	// (2) the thing we're referencing is a pure function.
183	// (3) the thing we're referencing is another inline function.
184	// This last can give us false negatives, but it's better than warning on
185	// wrappers for simple C library functions.
186	const FunctionDecl *UsedFn = dyn_cast<FunctionDecl>(Val: D);
187	bool DowngradeWarning = S.getSourceManager().isInMainFile(Loc);
188	if (!DowngradeWarning && UsedFn)
189	DowngradeWarning = UsedFn->isInlined() || UsedFn->hasAttr<ConstAttr>();
190
191	S.Diag(Loc, DowngradeWarning ? diag::ext_internal_in_extern_inline_quiet
192	: diag::ext_internal_in_extern_inline)
193	<< /*IsVar=*/!UsedFn << D;
194
195	S.MaybeSuggestAddingStaticToDecl(D: Current);
196
197	S.Diag(D->getCanonicalDecl()->getLocation(), diag::note_entity_declared_at)
198	<< D;
199	}
200
201	void Sema::MaybeSuggestAddingStaticToDecl(const FunctionDecl *Cur) {
202	const FunctionDecl *First = Cur->getFirstDecl();
203
204	// Suggest "static" on the function, if possible.
205	if (!hasAnyExplicitStorageClass(D: First)) {
206	SourceLocation DeclBegin = First->getSourceRange().getBegin();
207	Diag(DeclBegin, diag::note_convert_inline_to_static)
208	<< Cur << FixItHint::CreateInsertion(DeclBegin, "static ");
209	}
210	}
211
212	/// Determine whether the use of this declaration is valid, and
213	/// emit any corresponding diagnostics.
214	///
215	/// This routine diagnoses various problems with referencing
216	/// declarations that can occur when using a declaration. For example,
217	/// it might warn if a deprecated or unavailable declaration is being
218	/// used, or produce an error (and return true) if a C++0x deleted
219	/// function is being used.
220	///
221	/// \returns true if there was an error (this declaration cannot be
222	/// referenced), false otherwise.
223	///
224	bool Sema::DiagnoseUseOfDecl(NamedDecl *D, ArrayRef<SourceLocation> Locs,
225	const ObjCInterfaceDecl *UnknownObjCClass,
226	bool ObjCPropertyAccess,
227	bool AvoidPartialAvailabilityChecks,
228	ObjCInterfaceDecl *ClassReceiver,
229	bool SkipTrailingRequiresClause) {
230	SourceLocation Loc = Locs.front();
231	if (getLangOpts().CPlusPlus && isa<FunctionDecl>(Val: D)) {
232	// If there were any diagnostics suppressed by template argument deduction,
233	// emit them now.
234	auto Pos = SuppressedDiagnostics.find(D->getCanonicalDecl());
235	if (Pos != SuppressedDiagnostics.end()) {
236	for (const PartialDiagnosticAt &Suppressed : Pos->second)
237	Diag(Suppressed.first, Suppressed.second);
238
239	// Clear out the list of suppressed diagnostics, so that we don't emit
240	// them again for this specialization. However, we don't obsolete this
241	// entry from the table, because we want to avoid ever emitting these
242	// diagnostics again.
243	Pos->second.clear();
244	}
245
246	// C++ [basic.start.main]p3:
247	// The function 'main' shall not be used within a program.
248	if (cast<FunctionDecl>(D)->isMain())
249	Diag(Loc, diag::ext_main_used);
250
251	diagnoseUnavailableAlignedAllocation(FD: *cast<FunctionDecl>(Val: D), Loc);
252	}
253
254	// See if this is an auto-typed variable whose initializer we are parsing.
255	if (ParsingInitForAutoVars.count(D)) {
256	if (isa<BindingDecl>(Val: D)) {
257	Diag(Loc, diag::err_binding_cannot_appear_in_own_initializer)
258	<< D->getDeclName();
259	} else {
260	Diag(Loc, diag::err_auto_variable_cannot_appear_in_own_initializer)
261	<< D->getDeclName() << cast<VarDecl>(D)->getType();
262	}
263	return true;
264	}
265
266	if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Val: D)) {
267	// See if this is a deleted function.
268	if (FD->isDeleted()) {
269	auto *Ctor = dyn_cast<CXXConstructorDecl>(Val: FD);
270	if (Ctor && Ctor->isInheritingConstructor())
271	Diag(Loc, diag::err_deleted_inherited_ctor_use)
272	<< Ctor->getParent()
273	<< Ctor->getInheritedConstructor().getConstructor()->getParent();
274	else
275	Diag(Loc, diag::err_deleted_function_use);
276	NoteDeletedFunction(Decl: FD);
277	return true;
278	}
279
280	// [expr.prim.id]p4
281	// A program that refers explicitly or implicitly to a function with a
282	// trailing requires-clause whose constraint-expression is not satisfied,
283	// other than to declare it, is ill-formed. [...]
284	//
285	// See if this is a function with constraints that need to be satisfied.
286	// Check this before deducing the return type, as it might instantiate the
287	// definition.
288	if (!SkipTrailingRequiresClause && FD->getTrailingRequiresClause()) {
289	ConstraintSatisfaction Satisfaction;
290	if (CheckFunctionConstraints(FD, Satisfaction, UsageLoc: Loc,
291	/*ForOverloadResolution*/ true))
292	// A diagnostic will have already been generated (non-constant
293	// constraint expression, for example)
294	return true;
295	if (!Satisfaction.IsSatisfied) {
296	Diag(Loc,
297	diag::err_reference_to_function_with_unsatisfied_constraints)
298	<< D;
299	DiagnoseUnsatisfiedConstraint(Satisfaction);
300	return true;
301	}
302	}
303
304	// If the function has a deduced return type, and we can't deduce it,
305	// then we can't use it either.
306	if (getLangOpts().CPlusPlus14 && FD->getReturnType()->isUndeducedType() &&
307	DeduceReturnType(FD, Loc))
308	return true;
309
310	if (getLangOpts().CUDA && !CheckCUDACall(Loc, Callee: FD))
311	return true;
312
313	}
314
315	if (auto *MD = dyn_cast<CXXMethodDecl>(Val: D)) {
316	// Lambdas are only default-constructible or assignable in C++2a onwards.
317	if (MD->getParent()->isLambda() &&
318	((isa<CXXConstructorDecl>(Val: MD) &&
319	cast<CXXConstructorDecl>(Val: MD)->isDefaultConstructor()) ||
320	MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())) {
321	Diag(Loc, diag::warn_cxx17_compat_lambda_def_ctor_assign)
322	<< !isa<CXXConstructorDecl>(MD);
323	}
324	}
325
326	auto getReferencedObjCProp = [](const NamedDecl *D) ->
327	const ObjCPropertyDecl * {
328	if (const auto *MD = dyn_cast<ObjCMethodDecl>(Val: D))
329	return MD->findPropertyDecl();
330	return nullptr;
331	};
332	if (const ObjCPropertyDecl *ObjCPDecl = getReferencedObjCProp(D)) {
333	if (diagnoseArgIndependentDiagnoseIfAttrs(ObjCPDecl, Loc))
334	return true;
335	} else if (diagnoseArgIndependentDiagnoseIfAttrs(ND: D, Loc)) {
336	return true;
337	}
338
339	// [OpenMP 4.0], 2.15 declare reduction Directive, Restrictions
340	// Only the variables omp_in and omp_out are allowed in the combiner.
341	// Only the variables omp_priv and omp_orig are allowed in the
342	// initializer-clause.
343	auto *DRD = dyn_cast<OMPDeclareReductionDecl>(Val: CurContext);
344	if (LangOpts.OpenMP && DRD && !CurContext->containsDecl(D) &&
345	isa<VarDecl>(Val: D)) {
346	Diag(Loc, diag::err_omp_wrong_var_in_declare_reduction)
347	<< getCurFunction()->HasOMPDeclareReductionCombiner;
348	Diag(D->getLocation(), diag::note_entity_declared_at) << D;
349	return true;
350	}
351
352	// [OpenMP 5.0], 2.19.7.3. declare mapper Directive, Restrictions
353	// List-items in map clauses on this construct may only refer to the declared
354	// variable var and entities that could be referenced by a procedure defined
355	// at the same location.
356	// [OpenMP 5.2] Also allow iterator declared variables.
357	if (LangOpts.OpenMP && isa<VarDecl>(Val: D) &&
358	!isOpenMPDeclareMapperVarDeclAllowed(VD: cast<VarDecl>(Val: D))) {
359	Diag(Loc, diag::err_omp_declare_mapper_wrong_var)
360	<< getOpenMPDeclareMapperVarName();
361	Diag(D->getLocation(), diag::note_entity_declared_at) << D;
362	return true;
363	}
364
365	if (const auto *EmptyD = dyn_cast<UnresolvedUsingIfExistsDecl>(Val: D)) {
366	Diag(Loc, diag::err_use_of_empty_using_if_exists);
367	Diag(EmptyD->getLocation(), diag::note_empty_using_if_exists_here);
368	return true;
369	}
370
371	DiagnoseAvailabilityOfDecl(D, Locs, UnknownObjCClass, ObjCPropertyAccess,
372	AvoidPartialAvailabilityChecks, ClassReceiver);
373
374	DiagnoseUnusedOfDecl(S&: *this, D, Loc);
375
376	diagnoseUseOfInternalDeclInInlineFunction(S&: *this, D, Loc);
377
378	if (D->hasAttr<AvailableOnlyInDefaultEvalMethodAttr>()) {
379	if (getLangOpts().getFPEvalMethod() !=
380	LangOptions::FPEvalMethodKind::FEM_UnsetOnCommandLine &&
381	PP.getLastFPEvalPragmaLocation().isValid() &&
382	PP.getCurrentFPEvalMethod() != getLangOpts().getFPEvalMethod())
383	Diag(D->getLocation(),
384	diag::err_type_available_only_in_default_eval_method)
385	<< D->getName();
386	}
387
388	if (auto *VD = dyn_cast<ValueDecl>(Val: D))
389	checkTypeSupport(Ty: VD->getType(), Loc, D: VD);
390
391	if (LangOpts.SYCLIsDevice ||
392	(LangOpts.OpenMP && LangOpts.OpenMPIsTargetDevice)) {
393	if (!Context.getTargetInfo().isTLSSupported())
394	if (const auto *VD = dyn_cast<VarDecl>(D))
395	if (VD->getTLSKind() != VarDecl::TLS_None)
396	targetDiag(*Locs.begin(), diag::err_thread_unsupported);
397	}
398
399	if (isa<ParmVarDecl>(Val: D) && isa<RequiresExprBodyDecl>(D->getDeclContext()) &&
400	!isUnevaluatedContext()) {
401	// C++ [expr.prim.req.nested] p3
402	// A local parameter shall only appear as an unevaluated operand
403	// (Clause 8) within the constraint-expression.
404	Diag(Loc, diag::err_requires_expr_parameter_referenced_in_evaluated_context)
405	<< D;
406	Diag(D->getLocation(), diag::note_entity_declared_at) << D;
407	return true;
408	}
409
410	return false;
411	}
412
413	/// DiagnoseSentinelCalls - This routine checks whether a call or
414	/// message-send is to a declaration with the sentinel attribute, and
415	/// if so, it checks that the requirements of the sentinel are
416	/// satisfied.
417	void Sema::DiagnoseSentinelCalls(const NamedDecl *D, SourceLocation Loc,
418	ArrayRef<Expr *> Args) {
419	const SentinelAttr *Attr = D->getAttr<SentinelAttr>();
420	if (!Attr)
421	return;
422
423	// The number of formal parameters of the declaration.
424	unsigned NumFormalParams;
425
426	// The kind of declaration. This is also an index into a %select in
427	// the diagnostic.
428	enum { CK_Function, CK_Method, CK_Block } CalleeKind;
429
430	if (const auto *MD = dyn_cast<ObjCMethodDecl>(Val: D)) {
431	NumFormalParams = MD->param_size();
432	CalleeKind = CK_Method;
433	} else if (const auto *FD = dyn_cast<FunctionDecl>(Val: D)) {
434	NumFormalParams = FD->param_size();
435	CalleeKind = CK_Function;
436	} else if (const auto *VD = dyn_cast<VarDecl>(Val: D)) {
437	QualType Ty = VD->getType();
438	const FunctionType *Fn = nullptr;
439	if (const auto *PtrTy = Ty->getAs<PointerType>()) {
440	Fn = PtrTy->getPointeeType()->getAs<FunctionType>();
441	if (!Fn)
442	return;
443	CalleeKind = CK_Function;
444	} else if (const auto *PtrTy = Ty->getAs<BlockPointerType>()) {
445	Fn = PtrTy->getPointeeType()->castAs<FunctionType>();
446	CalleeKind = CK_Block;
447	} else {
448	return;
449	}
450
451	if (const auto *proto = dyn_cast<FunctionProtoType>(Val: Fn))
452	NumFormalParams = proto->getNumParams();
453	else
454	NumFormalParams = 0;
455	} else {
456	return;
457	}
458
459	// "NullPos" is the number of formal parameters at the end which
460	// effectively count as part of the variadic arguments. This is
461	// useful if you would prefer to not have *any* formal parameters,
462	// but the language forces you to have at least one.
463	unsigned NullPos = Attr->getNullPos();
464	assert((NullPos == 0 || NullPos == 1) && "invalid null position on sentinel");
465	NumFormalParams = (NullPos > NumFormalParams ? 0 : NumFormalParams - NullPos);
466
467	// The number of arguments which should follow the sentinel.
468	unsigned NumArgsAfterSentinel = Attr->getSentinel();
469
470	// If there aren't enough arguments for all the formal parameters,
471	// the sentinel, and the args after the sentinel, complain.
472	if (Args.size() < NumFormalParams + NumArgsAfterSentinel + 1) {
473	Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName();
474	Diag(D->getLocation(), diag::note_sentinel_here) << int(CalleeKind);
475	return;
476	}
477
478	// Otherwise, find the sentinel expression.
479	const Expr *SentinelExpr = Args[Args.size() - NumArgsAfterSentinel - 1];
480	if (!SentinelExpr)
481	return;
482	if (SentinelExpr->isValueDependent())
483	return;
484	if (Context.isSentinelNullExpr(E: SentinelExpr))
485	return;
486
487	// Pick a reasonable string to insert. Optimistically use 'nil', 'nullptr',
488	// or 'NULL' if those are actually defined in the context. Only use
489	// 'nil' for ObjC methods, where it's much more likely that the
490	// variadic arguments form a list of object pointers.
491	SourceLocation MissingNilLoc = getLocForEndOfToken(Loc: SentinelExpr->getEndLoc());
492	std::string NullValue;
493	if (CalleeKind == CK_Method && PP.isMacroDefined(Id: "nil"))
494	NullValue = "nil";
495	else if (getLangOpts().CPlusPlus11)
496	NullValue = "nullptr";
497	else if (PP.isMacroDefined(Id: "NULL"))
498	NullValue = "NULL";
499	else
500	NullValue = "(void*) 0";
501
502	if (MissingNilLoc.isInvalid())
503	Diag(Loc, diag::warn_missing_sentinel) << int(CalleeKind);
504	else
505	Diag(MissingNilLoc, diag::warn_missing_sentinel)
506	<< int(CalleeKind)
507	<< FixItHint::CreateInsertion(MissingNilLoc, ", " + NullValue);
508	Diag(D->getLocation(), diag::note_sentinel_here)
509	<< int(CalleeKind) << Attr->getRange();
510	}
511
512	SourceRange Sema::getExprRange(Expr *E) const {
513	return E ? E->getSourceRange() : SourceRange();
514	}
515
516	//===----------------------------------------------------------------------===//
517	// Standard Promotions and Conversions
518	//===----------------------------------------------------------------------===//
519
520	/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4).
521	ExprResult Sema::DefaultFunctionArrayConversion(Expr *E, bool Diagnose) {
522	// Handle any placeholder expressions which made it here.
523	if (E->hasPlaceholderType()) {
524	ExprResult result = CheckPlaceholderExpr(E);
525	if (result.isInvalid()) return ExprError();
526	E = result.get();
527	}
528
529	QualType Ty = E->getType();
530	assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type");
531
532	if (Ty->isFunctionType()) {
533	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: E->IgnoreParenCasts()))
534	if (auto *FD = dyn_cast<FunctionDecl>(Val: DRE->getDecl()))
535	if (!checkAddressOfFunctionIsAvailable(Function: FD, Complain: Diagnose, Loc: E->getExprLoc()))
536	return ExprError();
537
538	E = ImpCastExprToType(E, Type: Context.getPointerType(T: Ty),
539	CK: CK_FunctionToPointerDecay).get();
540	} else if (Ty->isArrayType()) {
541	// In C90 mode, arrays only promote to pointers if the array expression is
542	// an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has
543	// type 'array of type' is converted to an expression that has type 'pointer
544	// to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression
545	// that has type 'array of type' ...". The relevant change is "an lvalue"
546	// (C90) to "an expression" (C99).
547	//
548	// C++ 4.2p1:
549	// An lvalue or rvalue of type "array of N T" or "array of unknown bound of
550	// T" can be converted to an rvalue of type "pointer to T".
551	//
552	if (getLangOpts().C99 || getLangOpts().CPlusPlus || E->isLValue()) {
553	ExprResult Res = ImpCastExprToType(E, Type: Context.getArrayDecayedType(T: Ty),
554	CK: CK_ArrayToPointerDecay);
555	if (Res.isInvalid())
556	return ExprError();
557	E = Res.get();
558	}
559	}
560	return E;
561	}
562
563	static void CheckForNullPointerDereference(Sema &S, Expr *E) {
564	// Check to see if we are dereferencing a null pointer. If so,
565	// and if not volatile-qualified, this is undefined behavior that the
566	// optimizer will delete, so warn about it. People sometimes try to use this
567	// to get a deterministic trap and are surprised by clang's behavior. This
568	// only handles the pattern "*null", which is a very syntactic check.
569	const auto *UO = dyn_cast<UnaryOperator>(Val: E->IgnoreParenCasts());
570	if (UO && UO->getOpcode() == UO_Deref &&
571	UO->getSubExpr()->getType()->isPointerType()) {
572	const LangAS AS =
573	UO->getSubExpr()->getType()->getPointeeType().getAddressSpace();
574	if ((!isTargetAddressSpace(AS) ||
575	(isTargetAddressSpace(AS) && toTargetAddressSpace(AS) == 0)) &&
576	UO->getSubExpr()->IgnoreParenCasts()->isNullPointerConstant(
577	Ctx&: S.Context, NPC: Expr::NPC_ValueDependentIsNotNull) &&
578	!UO->getType().isVolatileQualified()) {
579	S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO,
580	S.PDiag(diag::warn_indirection_through_null)
581	<< UO->getSubExpr()->getSourceRange());
582	S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO,
583	S.PDiag(diag::note_indirection_through_null));
584	}
585	}
586	}
587
588	static void DiagnoseDirectIsaAccess(Sema &S, const ObjCIvarRefExpr *OIRE,
589	SourceLocation AssignLoc,
590	const Expr* RHS) {
591	const ObjCIvarDecl *IV = OIRE->getDecl();
592	if (!IV)
593	return;
594
595	DeclarationName MemberName = IV->getDeclName();
596	IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
597	if (!Member || !Member->isStr(Str: "isa"))
598	return;
599
600	const Expr *Base = OIRE->getBase();
601	QualType BaseType = Base->getType();
602	if (OIRE->isArrow())
603	BaseType = BaseType->getPointeeType();
604	if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>())
605	if (ObjCInterfaceDecl *IDecl = OTy->getInterface()) {
606	ObjCInterfaceDecl *ClassDeclared = nullptr;
607	ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(IVarName: Member, ClassDeclared);
608	if (!ClassDeclared->getSuperClass()
609	&& (*ClassDeclared->ivar_begin()) == IV) {
610	if (RHS) {
611	NamedDecl *ObjectSetClass =
612	S.LookupSingleName(S: S.TUScope,
613	Name: &S.Context.Idents.get(Name: "object_setClass"),
614	Loc: SourceLocation(), NameKind: S.LookupOrdinaryName);
615	if (ObjectSetClass) {
616	SourceLocation RHSLocEnd = S.getLocForEndOfToken(Loc: RHS->getEndLoc());
617	S.Diag(OIRE->getExprLoc(), diag::warn_objc_isa_assign)
618	<< FixItHint::CreateInsertion(OIRE->getBeginLoc(),
619	"object_setClass(")
620	<< FixItHint::CreateReplacement(
621	SourceRange(OIRE->getOpLoc(), AssignLoc), ",")
622	<< FixItHint::CreateInsertion(RHSLocEnd, ")");
623	}
624	else
625	S.Diag(OIRE->getLocation(), diag::warn_objc_isa_assign);
626	} else {
627	NamedDecl *ObjectGetClass =
628	S.LookupSingleName(S: S.TUScope,
629	Name: &S.Context.Idents.get(Name: "object_getClass"),
630	Loc: SourceLocation(), NameKind: S.LookupOrdinaryName);
631	if (ObjectGetClass)
632	S.Diag(OIRE->getExprLoc(), diag::warn_objc_isa_use)
633	<< FixItHint::CreateInsertion(OIRE->getBeginLoc(),
634	"object_getClass(")
635	<< FixItHint::CreateReplacement(
636	SourceRange(OIRE->getOpLoc(), OIRE->getEndLoc()), ")");
637	else
638	S.Diag(OIRE->getLocation(), diag::warn_objc_isa_use);
639	}
640	S.Diag(IV->getLocation(), diag::note_ivar_decl);
641	}
642	}
643	}
644
645	ExprResult Sema::DefaultLvalueConversion(Expr *E) {
646	// Handle any placeholder expressions which made it here.
647	if (E->hasPlaceholderType()) {
648	ExprResult result = CheckPlaceholderExpr(E);
649	if (result.isInvalid()) return ExprError();
650	E = result.get();
651	}
652
653	// C++ [conv.lval]p1:
654	// A glvalue of a non-function, non-array type T can be
655	// converted to a prvalue.
656	if (!E->isGLValue()) return E;
657
658	QualType T = E->getType();
659	assert(!T.isNull() && "r-value conversion on typeless expression?");
660
661	// lvalue-to-rvalue conversion cannot be applied to function or array types.
662	if (T->isFunctionType() || T->isArrayType())
663	return E;
664
665	// We don't want to throw lvalue-to-rvalue casts on top of
666	// expressions of certain types in C++.
667	if (getLangOpts().CPlusPlus &&
668	(E->getType() == Context.OverloadTy ||
669	T->isDependentType() ||
670	T->isRecordType()))
671	return E;
672
673	// The C standard is actually really unclear on this point, and
674	// DR106 tells us what the result should be but not why. It's
675	// generally best to say that void types just doesn't undergo
676	// lvalue-to-rvalue at all. Note that expressions of unqualified
677	// 'void' type are never l-values, but qualified void can be.
678	if (T->isVoidType())
679	return E;
680
681	// OpenCL usually rejects direct accesses to values of 'half' type.
682	if (getLangOpts().OpenCL &&
683	!getOpenCLOptions().isAvailableOption(Ext: "cl_khr_fp16", LO: getLangOpts()) &&
684	T->isHalfType()) {
685	Diag(E->getExprLoc(), diag::err_opencl_half_load_store)
686	<< 0 << T;
687	return ExprError();
688	}
689
690	CheckForNullPointerDereference(S&: *this, E);
691	if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(Val: E->IgnoreParenCasts())) {
692	NamedDecl *ObjectGetClass = LookupSingleName(S: TUScope,
693	Name: &Context.Idents.get(Name: "object_getClass"),
694	Loc: SourceLocation(), NameKind: LookupOrdinaryName);
695	if (ObjectGetClass)
696	Diag(E->getExprLoc(), diag::warn_objc_isa_use)
697	<< FixItHint::CreateInsertion(OISA->getBeginLoc(), "object_getClass(")
698	<< FixItHint::CreateReplacement(
699	SourceRange(OISA->getOpLoc(), OISA->getIsaMemberLoc()), ")");
700	else
701	Diag(E->getExprLoc(), diag::warn_objc_isa_use);
702	}
703	else if (const ObjCIvarRefExpr *OIRE =
704	dyn_cast<ObjCIvarRefExpr>(Val: E->IgnoreParenCasts()))
705	DiagnoseDirectIsaAccess(S&: *this, OIRE, AssignLoc: SourceLocation(), /* Expr*/RHS: nullptr);
706
707	// C++ [conv.lval]p1:
708	// [...] If T is a non-class type, the type of the prvalue is the
709	// cv-unqualified version of T. Otherwise, the type of the
710	// rvalue is T.
711	//
712	// C99 6.3.2.1p2:
713	// If the lvalue has qualified type, the value has the unqualified
714	// version of the type of the lvalue; otherwise, the value has the
715	// type of the lvalue.
716	if (T.hasQualifiers())
717	T = T.getUnqualifiedType();
718
719	// Under the MS ABI, lock down the inheritance model now.
720	if (T->isMemberPointerType() &&
721	Context.getTargetInfo().getCXXABI().isMicrosoft())
722	(void)isCompleteType(Loc: E->getExprLoc(), T);
723
724	ExprResult Res = CheckLValueToRValueConversionOperand(E);
725	if (Res.isInvalid())
726	return Res;
727	E = Res.get();
728
729	// Loading a __weak object implicitly retains the value, so we need a cleanup to
730	// balance that.
731	if (E->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
732	Cleanup.setExprNeedsCleanups(true);
733
734	if (E->getType().isDestructedType() == QualType::DK_nontrivial_c_struct)
735	Cleanup.setExprNeedsCleanups(true);
736
737	// C++ [conv.lval]p3:
738	// If T is cv std::nullptr_t, the result is a null pointer constant.
739	CastKind CK = T->isNullPtrType() ? CK_NullToPointer : CK_LValueToRValue;
740	Res = ImplicitCastExpr::Create(Context, T, Kind: CK, Operand: E, BasePath: nullptr, Cat: VK_PRValue,
741	FPO: CurFPFeatureOverrides());
742
743	// C11 6.3.2.1p2:
744	// ... if the lvalue has atomic type, the value has the non-atomic version
745	// of the type of the lvalue ...
746	if (const AtomicType *Atomic = T->getAs<AtomicType>()) {
747	T = Atomic->getValueType().getUnqualifiedType();
748	Res = ImplicitCastExpr::Create(Context, T, Kind: CK_AtomicToNonAtomic, Operand: Res.get(),
749	BasePath: nullptr, Cat: VK_PRValue, FPO: FPOptionsOverride());
750	}
751
752	return Res;
753	}
754
755	ExprResult Sema::DefaultFunctionArrayLvalueConversion(Expr *E, bool Diagnose) {
756	ExprResult Res = DefaultFunctionArrayConversion(E, Diagnose);
757	if (Res.isInvalid())
758	return ExprError();
759	Res = DefaultLvalueConversion(E: Res.get());
760	if (Res.isInvalid())
761	return ExprError();
762	return Res;
763	}
764
765	/// CallExprUnaryConversions - a special case of an unary conversion
766	/// performed on a function designator of a call expression.
767	ExprResult Sema::CallExprUnaryConversions(Expr *E) {
768	QualType Ty = E->getType();
769	ExprResult Res = E;
770	// Only do implicit cast for a function type, but not for a pointer
771	// to function type.
772	if (Ty->isFunctionType()) {
773	Res = ImpCastExprToType(E, Type: Context.getPointerType(T: Ty),
774	CK: CK_FunctionToPointerDecay);
775	if (Res.isInvalid())
776	return ExprError();
777	}
778	Res = DefaultLvalueConversion(E: Res.get());
779	if (Res.isInvalid())
780	return ExprError();
781	return Res.get();
782	}
783
784	/// UsualUnaryConversions - Performs various conversions that are common to most
785	/// operators (C99 6.3). The conversions of array and function types are
786	/// sometimes suppressed. For example, the array->pointer conversion doesn't
787	/// apply if the array is an argument to the sizeof or address (&) operators.
788	/// In these instances, this routine should *not* be called.
789	ExprResult Sema::UsualUnaryConversions(Expr *E) {
790	// First, convert to an r-value.
791	ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
792	if (Res.isInvalid())
793	return ExprError();
794	E = Res.get();
795
796	QualType Ty = E->getType();
797	assert(!Ty.isNull() && "UsualUnaryConversions - missing type");
798
799	LangOptions::FPEvalMethodKind EvalMethod = CurFPFeatures.getFPEvalMethod();
800	if (EvalMethod != LangOptions::FEM_Source && Ty->isFloatingType() &&
801	(getLangOpts().getFPEvalMethod() !=
802	LangOptions::FPEvalMethodKind::FEM_UnsetOnCommandLine ||
803	PP.getLastFPEvalPragmaLocation().isValid())) {
804	switch (EvalMethod) {
805	default:
806	llvm_unreachable("Unrecognized float evaluation method");
807	break;
808	case LangOptions::FEM_UnsetOnCommandLine:
809	llvm_unreachable("Float evaluation method should be set by now");
810	break;
811	case LangOptions::FEM_Double:
812	if (Context.getFloatingTypeOrder(LHS: Context.DoubleTy, RHS: Ty) > 0)
813	// Widen the expression to double.
814	return Ty->isComplexType()
815	? ImpCastExprToType(E,
816	Type: Context.getComplexType(Context.DoubleTy),
817	CK: CK_FloatingComplexCast)
818	: ImpCastExprToType(E, Type: Context.DoubleTy, CK: CK_FloatingCast);
819	break;
820	case LangOptions::FEM_Extended:
821	if (Context.getFloatingTypeOrder(LHS: Context.LongDoubleTy, RHS: Ty) > 0)
822	// Widen the expression to long double.
823	return Ty->isComplexType()
824	? ImpCastExprToType(
825	E, Type: Context.getComplexType(Context.LongDoubleTy),
826	CK: CK_FloatingComplexCast)
827	: ImpCastExprToType(E, Type: Context.LongDoubleTy,
828	CK: CK_FloatingCast);
829	break;
830	}
831	}
832
833	// Half FP have to be promoted to float unless it is natively supported
834	if (Ty->isHalfType() && !getLangOpts().NativeHalfType)
835	return ImpCastExprToType(E: Res.get(), Type: Context.FloatTy, CK: CK_FloatingCast);
836
837	// Try to perform integral promotions if the object has a theoretically
838	// promotable type.
839	if (Ty->isIntegralOrUnscopedEnumerationType()) {
840	// C99 6.3.1.1p2:
841	//
842	// The following may be used in an expression wherever an int or
843	// unsigned int may be used:
844	// - an object or expression with an integer type whose integer
845	// conversion rank is less than or equal to the rank of int
846	// and unsigned int.
847	// - A bit-field of type _Bool, int, signed int, or unsigned int.
848	//
849	// If an int can represent all values of the original type, the
850	// value is converted to an int; otherwise, it is converted to an
851	// unsigned int. These are called the integer promotions. All
852	// other types are unchanged by the integer promotions.
853
854	QualType PTy = Context.isPromotableBitField(E);
855	if (!PTy.isNull()) {
856	E = ImpCastExprToType(E, Type: PTy, CK: CK_IntegralCast).get();
857	return E;
858	}
859	if (Context.isPromotableIntegerType(T: Ty)) {
860	QualType PT = Context.getPromotedIntegerType(PromotableType: Ty);
861	E = ImpCastExprToType(E, Type: PT, CK: CK_IntegralCast).get();
862	return E;
863	}
864	}
865	return E;
866	}
867
868	/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that
869	/// do not have a prototype. Arguments that have type float or __fp16
870	/// are promoted to double. All other argument types are converted by
871	/// UsualUnaryConversions().
872	ExprResult Sema::DefaultArgumentPromotion(Expr *E) {
873	QualType Ty = E->getType();
874	assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type");
875
876	ExprResult Res = UsualUnaryConversions(E);
877	if (Res.isInvalid())
878	return ExprError();
879	E = Res.get();
880
881	// If this is a 'float' or '__fp16' (CVR qualified or typedef)
882	// promote to double.
883	// Note that default argument promotion applies only to float (and
884	// half/fp16); it does not apply to _Float16.
885	const BuiltinType *BTy = Ty->getAs<BuiltinType>();
886	if (BTy && (BTy->getKind() == BuiltinType::Half ||
887	BTy->getKind() == BuiltinType::Float)) {
888	if (getLangOpts().OpenCL &&
889	!getOpenCLOptions().isAvailableOption(Ext: "cl_khr_fp64", LO: getLangOpts())) {
890	if (BTy->getKind() == BuiltinType::Half) {
891	E = ImpCastExprToType(E, Type: Context.FloatTy, CK: CK_FloatingCast).get();
892	}
893	} else {
894	E = ImpCastExprToType(E, Type: Context.DoubleTy, CK: CK_FloatingCast).get();
895	}
896	}
897	if (BTy &&
898	getLangOpts().getExtendIntArgs() ==
899	LangOptions::ExtendArgsKind::ExtendTo64 &&
900	Context.getTargetInfo().supportsExtendIntArgs() && Ty->isIntegerType() &&
901	Context.getTypeSizeInChars(BTy) <
902	Context.getTypeSizeInChars(Context.LongLongTy)) {
903	E = (Ty->isUnsignedIntegerType())
904	? ImpCastExprToType(E, Type: Context.UnsignedLongLongTy, CK: CK_IntegralCast)
905	.get()
906	: ImpCastExprToType(E, Type: Context.LongLongTy, CK: CK_IntegralCast).get();
907	assert(8 == Context.getTypeSizeInChars(Context.LongLongTy).getQuantity() &&
908	"Unexpected typesize for LongLongTy");
909	}
910
911	// C++ performs lvalue-to-rvalue conversion as a default argument
912	// promotion, even on class types, but note:
913	// C++11 [conv.lval]p2:
914	// When an lvalue-to-rvalue conversion occurs in an unevaluated
915	// operand or a subexpression thereof the value contained in the
916	// referenced object is not accessed. Otherwise, if the glvalue
917	// has a class type, the conversion copy-initializes a temporary
918	// of type T from the glvalue and the result of the conversion
919	// is a prvalue for the temporary.
920	// FIXME: add some way to gate this entire thing for correctness in
921	// potentially potentially evaluated contexts.
922	if (getLangOpts().CPlusPlus && E->isGLValue() && !isUnevaluatedContext()) {
923	ExprResult Temp = PerformCopyInitialization(
924	Entity: InitializedEntity::InitializeTemporary(Type: E->getType()),
925	EqualLoc: E->getExprLoc(), Init: E);
926	if (Temp.isInvalid())
927	return ExprError();
928	E = Temp.get();
929	}
930
931	return E;
932	}
933
934	/// Determine the degree of POD-ness for an expression.
935	/// Incomplete types are considered POD, since this check can be performed
936	/// when we're in an unevaluated context.
937	Sema::VarArgKind Sema::isValidVarArgType(const QualType &Ty) {
938	if (Ty->isIncompleteType()) {
939	// C++11 [expr.call]p7:
940	// After these conversions, if the argument does not have arithmetic,
941	// enumeration, pointer, pointer to member, or class type, the program
942	// is ill-formed.
943	//
944	// Since we've already performed array-to-pointer and function-to-pointer
945	// decay, the only such type in C++ is cv void. This also handles
946	// initializer lists as variadic arguments.
947	if (Ty->isVoidType())
948	return VAK_Invalid;
949
950	if (Ty->isObjCObjectType())
951	return VAK_Invalid;
952	return VAK_Valid;
953	}
954
955	if (Ty.isDestructedType() == QualType::DK_nontrivial_c_struct)
956	return VAK_Invalid;
957
958	if (Context.getTargetInfo().getTriple().isWasm() &&
959	Ty.isWebAssemblyReferenceType()) {
960	return VAK_Invalid;
961	}
962
963	if (Ty.isCXX98PODType(Context))
964	return VAK_Valid;
965
966	// C++11 [expr.call]p7:
967	// Passing a potentially-evaluated argument of class type (Clause 9)
968	// having a non-trivial copy constructor, a non-trivial move constructor,
969	// or a non-trivial destructor, with no corresponding parameter,
970	// is conditionally-supported with implementation-defined semantics.
971	if (getLangOpts().CPlusPlus11 && !Ty->isDependentType())
972	if (CXXRecordDecl *Record = Ty->getAsCXXRecordDecl())
973	if (!Record->hasNonTrivialCopyConstructor() &&
974	!Record->hasNonTrivialMoveConstructor() &&
975	!Record->hasNonTrivialDestructor())
976	return VAK_ValidInCXX11;
977
978	if (getLangOpts().ObjCAutoRefCount && Ty->isObjCLifetimeType())
979	return VAK_Valid;
980
981	if (Ty->isObjCObjectType())
982	return VAK_Invalid;
983
984	if (getLangOpts().MSVCCompat)
985	return VAK_MSVCUndefined;
986
987	// FIXME: In C++11, these cases are conditionally-supported, meaning we're
988	// permitted to reject them. We should consider doing so.
989	return VAK_Undefined;
990	}
991
992	void Sema::checkVariadicArgument(const Expr *E, VariadicCallType CT) {
993	// Don't allow one to pass an Objective-C interface to a vararg.
994	const QualType &Ty = E->getType();
995	VarArgKind VAK = isValidVarArgType(Ty);
996
997	// Complain about passing non-POD types through varargs.
998	switch (VAK) {
999	case VAK_ValidInCXX11:
1000	DiagRuntimeBehavior(
1001	E->getBeginLoc(), nullptr,
1002	PDiag(diag::warn_cxx98_compat_pass_non_pod_arg_to_vararg) << Ty << CT);
1003	[[fallthrough]];
1004	case VAK_Valid:
1005	if (Ty->isRecordType()) {
1006	// This is unlikely to be what the user intended. If the class has a
1007	// 'c_str' member function, the user probably meant to call that.
1008	DiagRuntimeBehavior(E->getBeginLoc(), nullptr,
1009	PDiag(diag::warn_pass_class_arg_to_vararg)
1010	<< Ty << CT << hasCStrMethod(E) << ".c_str()");
1011	}
1012	break;
1013
1014	case VAK_Undefined:
1015	case VAK_MSVCUndefined:
1016	DiagRuntimeBehavior(E->getBeginLoc(), nullptr,
1017	PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg)
1018	<< getLangOpts().CPlusPlus11 << Ty << CT);
1019	break;
1020
1021	case VAK_Invalid:
1022	if (Ty.isDestructedType() == QualType::DK_nontrivial_c_struct)
1023	Diag(E->getBeginLoc(),
1024	diag::err_cannot_pass_non_trivial_c_struct_to_vararg)
1025	<< Ty << CT;
1026	else if (Ty->isObjCObjectType())
1027	DiagRuntimeBehavior(E->getBeginLoc(), nullptr,
1028	PDiag(diag::err_cannot_pass_objc_interface_to_vararg)
1029	<< Ty << CT);
1030	else
1031	Diag(E->getBeginLoc(), diag::err_cannot_pass_to_vararg)
1032	<< isa<InitListExpr>(E) << Ty << CT;
1033	break;
1034	}
1035	}
1036
1037	/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but
1038	/// will create a trap if the resulting type is not a POD type.
1039	ExprResult Sema::DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT,
1040	FunctionDecl *FDecl) {
1041	if (const BuiltinType *PlaceholderTy = E->getType()->getAsPlaceholderType()) {
1042	// Strip the unbridged-cast placeholder expression off, if applicable.
1043	if (PlaceholderTy->getKind() == BuiltinType::ARCUnbridgedCast &&
1044	(CT == VariadicMethod ||
1045	(FDecl && FDecl->hasAttr<CFAuditedTransferAttr>()))) {
1046	E = stripARCUnbridgedCast(e: E);
1047
1048	// Otherwise, do normal placeholder checking.
1049	} else {
1050	ExprResult ExprRes = CheckPlaceholderExpr(E);
1051	if (ExprRes.isInvalid())
1052	return ExprError();
1053	E = ExprRes.get();
1054	}
1055	}
1056
1057	ExprResult ExprRes = DefaultArgumentPromotion(E);
1058	if (ExprRes.isInvalid())
1059	return ExprError();
1060
1061	// Copy blocks to the heap.
1062	if (ExprRes.get()->getType()->isBlockPointerType())
1063	maybeExtendBlockObject(E&: ExprRes);
1064
1065	E = ExprRes.get();
1066
1067	// Diagnostics regarding non-POD argument types are
1068	// emitted along with format string checking in Sema::CheckFunctionCall().
1069	if (isValidVarArgType(Ty: E->getType()) == VAK_Undefined) {
1070	// Turn this into a trap.
1071	CXXScopeSpec SS;
1072	SourceLocation TemplateKWLoc;
1073	UnqualifiedId Name;
1074	Name.setIdentifier(Id: PP.getIdentifierInfo(Name: "__builtin_trap"),
1075	IdLoc: E->getBeginLoc());
1076	ExprResult TrapFn = ActOnIdExpression(S: TUScope, SS, TemplateKWLoc, Id&: Name,
1077	/*HasTrailingLParen=*/true,
1078	/*IsAddressOfOperand=*/false);
1079	if (TrapFn.isInvalid())
1080	return ExprError();
1081
1082	ExprResult Call = BuildCallExpr(S: TUScope, Fn: TrapFn.get(), LParenLoc: E->getBeginLoc(),
1083	ArgExprs: std::nullopt, RParenLoc: E->getEndLoc());
1084	if (Call.isInvalid())
1085	return ExprError();
1086
1087	ExprResult Comma =
1088	ActOnBinOp(S: TUScope, TokLoc: E->getBeginLoc(), Kind: tok::comma, LHSExpr: Call.get(), RHSExpr: E);
1089	if (Comma.isInvalid())
1090	return ExprError();
1091	return Comma.get();
1092	}
1093
1094	if (!getLangOpts().CPlusPlus &&
1095	RequireCompleteType(E->getExprLoc(), E->getType(),
1096	diag::err_call_incomplete_argument))
1097	return ExprError();
1098
1099	return E;
1100	}
1101
1102	/// Converts an integer to complex float type. Helper function of
1103	/// UsualArithmeticConversions()
1104	///
1105	/// \return false if the integer expression is an integer type and is
1106	/// successfully converted to the complex type.
1107	static bool handleIntegerToComplexFloatConversion(Sema &S, ExprResult &IntExpr,
1108	ExprResult &ComplexExpr,
1109	QualType IntTy,
1110	QualType ComplexTy,
1111	bool SkipCast) {
1112	if (IntTy->isComplexType() || IntTy->isRealFloatingType()) return true;
1113	if (SkipCast) return false;
1114	if (IntTy->isIntegerType()) {
1115	QualType fpTy = ComplexTy->castAs<ComplexType>()->getElementType();
1116	IntExpr = S.ImpCastExprToType(E: IntExpr.get(), Type: fpTy, CK: CK_IntegralToFloating);
1117	IntExpr = S.ImpCastExprToType(E: IntExpr.get(), Type: ComplexTy,
1118	CK: CK_FloatingRealToComplex);
1119	} else {
1120	assert(IntTy->isComplexIntegerType());
1121	IntExpr = S.ImpCastExprToType(E: IntExpr.get(), Type: ComplexTy,
1122	CK: CK_IntegralComplexToFloatingComplex);
1123	}
1124	return false;
1125	}
1126
1127	// This handles complex/complex, complex/float, or float/complex.
1128	// When both operands are complex, the shorter operand is converted to the
1129	// type of the longer, and that is the type of the result. This corresponds
1130	// to what is done when combining two real floating-point operands.
1131	// The fun begins when size promotion occur across type domains.
1132	// From H&S 6.3.4: When one operand is complex and the other is a real
1133	// floating-point type, the less precise type is converted, within it's
1134	// real or complex domain, to the precision of the other type. For example,
1135	// when combining a "long double" with a "double _Complex", the
1136	// "double _Complex" is promoted to "long double _Complex".
1137	static QualType handleComplexFloatConversion(Sema &S, ExprResult &Shorter,
1138	QualType ShorterType,
1139	QualType LongerType,
1140	bool PromotePrecision) {
1141	bool LongerIsComplex = isa<ComplexType>(Val: LongerType.getCanonicalType());
1142	QualType Result =
1143	LongerIsComplex ? LongerType : S.Context.getComplexType(T: LongerType);
1144
1145	if (PromotePrecision) {
1146	if (isa<ComplexType>(Val: ShorterType.getCanonicalType())) {
1147	Shorter =
1148	S.ImpCastExprToType(E: Shorter.get(), Type: Result, CK: CK_FloatingComplexCast);
1149	} else {
1150	if (LongerIsComplex)
1151	LongerType = LongerType->castAs<ComplexType>()->getElementType();
1152	Shorter = S.ImpCastExprToType(E: Shorter.get(), Type: LongerType, CK: CK_FloatingCast);
1153	}
1154	}
1155	return Result;
1156	}
1157
1158	/// Handle arithmetic conversion with complex types. Helper function of
1159	/// UsualArithmeticConversions()
1160	static QualType handleComplexConversion(Sema &S, ExprResult &LHS,
1161	ExprResult &RHS, QualType LHSType,
1162	QualType RHSType, bool IsCompAssign) {
1163	// if we have an integer operand, the result is the complex type.
1164	if (!handleIntegerToComplexFloatConversion(S, IntExpr&: RHS, ComplexExpr&: LHS, IntTy: RHSType, ComplexTy: LHSType,
1165	/*SkipCast=*/false))
1166	return LHSType;
1167	if (!handleIntegerToComplexFloatConversion(S, IntExpr&: LHS, ComplexExpr&: RHS, IntTy: LHSType, ComplexTy: RHSType,
1168	/*SkipCast=*/IsCompAssign))
1169	return RHSType;
1170
1171	// Compute the rank of the two types, regardless of whether they are complex.
1172	int Order = S.Context.getFloatingTypeOrder(LHS: LHSType, RHS: RHSType);
1173	if (Order < 0)
1174	// Promote the precision of the LHS if not an assignment.
1175	return handleComplexFloatConversion(S, Shorter&: LHS, ShorterType: LHSType, LongerType: RHSType,
1176	/*PromotePrecision=*/!IsCompAssign);
1177	// Promote the precision of the RHS unless it is already the same as the LHS.
1178	return handleComplexFloatConversion(S, Shorter&: RHS, ShorterType: RHSType, LongerType: LHSType,
1179	/*PromotePrecision=*/Order > 0);
1180	}
1181
1182	/// Handle arithmetic conversion from integer to float. Helper function
1183	/// of UsualArithmeticConversions()
1184	static QualType handleIntToFloatConversion(Sema &S, ExprResult &FloatExpr,
1185	ExprResult &IntExpr,
1186	QualType FloatTy, QualType IntTy,
1187	bool ConvertFloat, bool ConvertInt) {
1188	if (IntTy->isIntegerType()) {
1189	if (ConvertInt)
1190	// Convert intExpr to the lhs floating point type.
1191	IntExpr = S.ImpCastExprToType(E: IntExpr.get(), Type: FloatTy,
1192	CK: CK_IntegralToFloating);
1193	return FloatTy;
1194	}
1195
1196	// Convert both sides to the appropriate complex float.
1197	assert(IntTy->isComplexIntegerType());
1198	QualType result = S.Context.getComplexType(T: FloatTy);
1199
1200	// _Complex int -> _Complex float
1201	if (ConvertInt)
1202	IntExpr = S.ImpCastExprToType(E: IntExpr.get(), Type: result,
1203	CK: CK_IntegralComplexToFloatingComplex);
1204
1205	// float -> _Complex float
1206	if (ConvertFloat)
1207	FloatExpr = S.ImpCastExprToType(E: FloatExpr.get(), Type: result,
1208	CK: CK_FloatingRealToComplex);
1209
1210	return result;
1211	}
1212
1213	/// Handle arithmethic conversion with floating point types. Helper
1214	/// function of UsualArithmeticConversions()
1215	static QualType handleFloatConversion(Sema &S, ExprResult &LHS,
1216	ExprResult &RHS, QualType LHSType,
1217	QualType RHSType, bool IsCompAssign) {
1218	bool LHSFloat = LHSType->isRealFloatingType();
1219	bool RHSFloat = RHSType->isRealFloatingType();
1220
1221	// N1169 4.1.4: If one of the operands has a floating type and the other
1222	// operand has a fixed-point type, the fixed-point operand
1223	// is converted to the floating type [...]
1224	if (LHSType->isFixedPointType() || RHSType->isFixedPointType()) {
1225	if (LHSFloat)
1226	RHS = S.ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_FixedPointToFloating);
1227	else if (!IsCompAssign)
1228	LHS = S.ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_FixedPointToFloating);
1229	return LHSFloat ? LHSType : RHSType;
1230	}
1231
1232	// If we have two real floating types, convert the smaller operand
1233	// to the bigger result.
1234	if (LHSFloat && RHSFloat) {
1235	int order = S.Context.getFloatingTypeOrder(LHS: LHSType, RHS: RHSType);
1236	if (order > 0) {
1237	RHS = S.ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_FloatingCast);
1238	return LHSType;
1239	}
1240
1241	assert(order < 0 && "illegal float comparison");
1242	if (!IsCompAssign)
1243	LHS = S.ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_FloatingCast);
1244	return RHSType;
1245	}
1246
1247	if (LHSFloat) {
1248	// Half FP has to be promoted to float unless it is natively supported
1249	if (LHSType->isHalfType() && !S.getLangOpts().NativeHalfType)
1250	LHSType = S.Context.FloatTy;
1251
1252	return handleIntToFloatConversion(S, FloatExpr&: LHS, IntExpr&: RHS, FloatTy: LHSType, IntTy: RHSType,
1253	/*ConvertFloat=*/!IsCompAssign,
1254	/*ConvertInt=*/ true);
1255	}
1256	assert(RHSFloat);
1257	return handleIntToFloatConversion(S, FloatExpr&: RHS, IntExpr&: LHS, FloatTy: RHSType, IntTy: LHSType,
1258	/*ConvertFloat=*/ true,
1259	/*ConvertInt=*/!IsCompAssign);
1260	}
1261
1262	/// Diagnose attempts to convert between __float128, __ibm128 and
1263	/// long double if there is no support for such conversion.
1264	/// Helper function of UsualArithmeticConversions().
1265	static bool unsupportedTypeConversion(const Sema &S, QualType LHSType,
1266	QualType RHSType) {
1267	// No issue if either is not a floating point type.
1268	if (!LHSType->isFloatingType() || !RHSType->isFloatingType())
1269	return false;
1270
1271	// No issue if both have the same 128-bit float semantics.
1272	auto *LHSComplex = LHSType->getAs<ComplexType>();
1273	auto *RHSComplex = RHSType->getAs<ComplexType>();
1274
1275	QualType LHSElem = LHSComplex ? LHSComplex->getElementType() : LHSType;
1276	QualType RHSElem = RHSComplex ? RHSComplex->getElementType() : RHSType;
1277
1278	const llvm::fltSemantics &LHSSem = S.Context.getFloatTypeSemantics(T: LHSElem);
1279	const llvm::fltSemantics &RHSSem = S.Context.getFloatTypeSemantics(T: RHSElem);
1280
1281	if ((&LHSSem != &llvm::APFloat::PPCDoubleDouble() ||
1282	&RHSSem != &llvm::APFloat::IEEEquad()) &&
1283	(&LHSSem != &llvm::APFloat::IEEEquad() ||
1284	&RHSSem != &llvm::APFloat::PPCDoubleDouble()))
1285	return false;
1286
1287	return true;
1288	}
1289
1290	typedef ExprResult PerformCastFn(Sema &S, Expr *operand, QualType toType);
1291
1292	namespace {
1293	/// These helper callbacks are placed in an anonymous namespace to
1294	/// permit their use as function template parameters.
1295	ExprResult doIntegralCast(Sema &S, Expr *op, QualType toType) {
1296	return S.ImpCastExprToType(E: op, Type: toType, CK: CK_IntegralCast);
1297	}
1298
1299	ExprResult doComplexIntegralCast(Sema &S, Expr *op, QualType toType) {
1300	return S.ImpCastExprToType(E: op, Type: S.Context.getComplexType(T: toType),
1301	CK: CK_IntegralComplexCast);
1302	}
1303	}
1304
1305	/// Handle integer arithmetic conversions. Helper function of
1306	/// UsualArithmeticConversions()
1307	template <PerformCastFn doLHSCast, PerformCastFn doRHSCast>
1308	static QualType handleIntegerConversion(Sema &S, ExprResult &LHS,
1309	ExprResult &RHS, QualType LHSType,
1310	QualType RHSType, bool IsCompAssign) {
1311	// The rules for this case are in C99 6.3.1.8
1312	int order = S.Context.getIntegerTypeOrder(LHS: LHSType, RHS: RHSType);
1313	bool LHSSigned = LHSType->hasSignedIntegerRepresentation();
1314	bool RHSSigned = RHSType->hasSignedIntegerRepresentation();
1315	if (LHSSigned == RHSSigned) {
1316	// Same signedness; use the higher-ranked type
1317	if (order >= 0) {
1318	RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1319	return LHSType;
1320	} else if (!IsCompAssign)
1321	LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1322	return RHSType;
1323	} else if (order != (LHSSigned ? 1 : -1)) {
1324	// The unsigned type has greater than or equal rank to the
1325	// signed type, so use the unsigned type
1326	if (RHSSigned) {
1327	RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1328	return LHSType;
1329	} else if (!IsCompAssign)
1330	LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1331	return RHSType;
1332	} else if (S.Context.getIntWidth(T: LHSType) != S.Context.getIntWidth(T: RHSType)) {
1333	// The two types are different widths; if we are here, that
1334	// means the signed type is larger than the unsigned type, so
1335	// use the signed type.
1336	if (LHSSigned) {
1337	RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1338	return LHSType;
1339	} else if (!IsCompAssign)
1340	LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1341	return RHSType;
1342	} else {
1343	// The signed type is higher-ranked than the unsigned type,
1344	// but isn't actually any bigger (like unsigned int and long
1345	// on most 32-bit systems). Use the unsigned type corresponding
1346	// to the signed type.
1347	QualType result =
1348	S.Context.getCorrespondingUnsignedType(T: LHSSigned ? LHSType : RHSType);
1349	RHS = (*doRHSCast)(S, RHS.get(), result);
1350	if (!IsCompAssign)
1351	LHS = (*doLHSCast)(S, LHS.get(), result);
1352	return result;
1353	}
1354	}
1355
1356	/// Handle conversions with GCC complex int extension. Helper function
1357	/// of UsualArithmeticConversions()
1358	static QualType handleComplexIntConversion(Sema &S, ExprResult &LHS,
1359	ExprResult &RHS, QualType LHSType,
1360	QualType RHSType,
1361	bool IsCompAssign) {
1362	const ComplexType *LHSComplexInt = LHSType->getAsComplexIntegerType();
1363	const ComplexType *RHSComplexInt = RHSType->getAsComplexIntegerType();
1364
1365	if (LHSComplexInt && RHSComplexInt) {
1366	QualType LHSEltType = LHSComplexInt->getElementType();
1367	QualType RHSEltType = RHSComplexInt->getElementType();
1368	QualType ScalarType =
1369	handleIntegerConversion<doComplexIntegralCast, doComplexIntegralCast>
1370	(S, LHS, RHS, LHSType: LHSEltType, RHSType: RHSEltType, IsCompAssign);
1371
1372	return S.Context.getComplexType(T: ScalarType);
1373	}
1374
1375	if (LHSComplexInt) {
1376	QualType LHSEltType = LHSComplexInt->getElementType();
1377	QualType ScalarType =
1378	handleIntegerConversion<doComplexIntegralCast, doIntegralCast>
1379	(S, LHS, RHS, LHSType: LHSEltType, RHSType, IsCompAssign);
1380	QualType ComplexType = S.Context.getComplexType(T: ScalarType);
1381	RHS = S.ImpCastExprToType(E: RHS.get(), Type: ComplexType,
1382	CK: CK_IntegralRealToComplex);
1383
1384	return ComplexType;
1385	}
1386
1387	assert(RHSComplexInt);
1388
1389	QualType RHSEltType = RHSComplexInt->getElementType();
1390	QualType ScalarType =
1391	handleIntegerConversion<doIntegralCast, doComplexIntegralCast>
1392	(S, LHS, RHS, LHSType, RHSType: RHSEltType, IsCompAssign);
1393	QualType ComplexType = S.Context.getComplexType(T: ScalarType);
1394
1395	if (!IsCompAssign)
1396	LHS = S.ImpCastExprToType(E: LHS.get(), Type: ComplexType,
1397	CK: CK_IntegralRealToComplex);
1398	return ComplexType;
1399	}
1400
1401	/// Return the rank of a given fixed point or integer type. The value itself
1402	/// doesn't matter, but the values must be increasing with proper increasing
1403	/// rank as described in N1169 4.1.1.
1404	static unsigned GetFixedPointRank(QualType Ty) {
1405	const auto *BTy = Ty->getAs<BuiltinType>();
1406	assert(BTy && "Expected a builtin type.");
1407
1408	switch (BTy->getKind()) {
1409	case BuiltinType::ShortFract:
1410	case BuiltinType::UShortFract:
1411	case BuiltinType::SatShortFract:
1412	case BuiltinType::SatUShortFract:
1413	return 1;
1414	case BuiltinType::Fract:
1415	case BuiltinType::UFract:
1416	case BuiltinType::SatFract:
1417	case BuiltinType::SatUFract:
1418	return 2;
1419	case BuiltinType::LongFract:
1420	case BuiltinType::ULongFract:
1421	case BuiltinType::SatLongFract:
1422	case BuiltinType::SatULongFract:
1423	return 3;
1424	case BuiltinType::ShortAccum:
1425	case BuiltinType::UShortAccum:
1426	case BuiltinType::SatShortAccum:
1427	case BuiltinType::SatUShortAccum:
1428	return 4;
1429	case BuiltinType::Accum:
1430	case BuiltinType::UAccum:
1431	case BuiltinType::SatAccum:
1432	case BuiltinType::SatUAccum:
1433	return 5;
1434	case BuiltinType::LongAccum:
1435	case BuiltinType::ULongAccum:
1436	case BuiltinType::SatLongAccum:
1437	case BuiltinType::SatULongAccum:
1438	return 6;
1439	default:
1440	if (BTy->isInteger())
1441	return 0;
1442	llvm_unreachable("Unexpected fixed point or integer type");
1443	}
1444	}
1445
1446	/// handleFixedPointConversion - Fixed point operations between fixed
1447	/// point types and integers or other fixed point types do not fall under
1448	/// usual arithmetic conversion since these conversions could result in loss
1449	/// of precsision (N1169 4.1.4). These operations should be calculated with
1450	/// the full precision of their result type (N1169 4.1.6.2.1).
1451	static QualType handleFixedPointConversion(Sema &S, QualType LHSTy,
1452	QualType RHSTy) {
1453	assert((LHSTy->isFixedPointType() || RHSTy->isFixedPointType()) &&
1454	"Expected at least one of the operands to be a fixed point type");
1455	assert((LHSTy->isFixedPointOrIntegerType() ||
1456	RHSTy->isFixedPointOrIntegerType()) &&
1457	"Special fixed point arithmetic operation conversions are only "
1458	"applied to ints or other fixed point types");
1459
1460	// If one operand has signed fixed-point type and the other operand has
1461	// unsigned fixed-point type, then the unsigned fixed-point operand is
1462	// converted to its corresponding signed fixed-point type and the resulting
1463	// type is the type of the converted operand.
1464	if (RHSTy->isSignedFixedPointType() && LHSTy->isUnsignedFixedPointType())
1465	LHSTy = S.Context.getCorrespondingSignedFixedPointType(Ty: LHSTy);
1466	else if (RHSTy->isUnsignedFixedPointType() && LHSTy->isSignedFixedPointType())
1467	RHSTy = S.Context.getCorrespondingSignedFixedPointType(Ty: RHSTy);
1468
1469	// The result type is the type with the highest rank, whereby a fixed-point
1470	// conversion rank is always greater than an integer conversion rank; if the
1471	// type of either of the operands is a saturating fixedpoint type, the result
1472	// type shall be the saturating fixed-point type corresponding to the type
1473	// with the highest rank; the resulting value is converted (taking into
1474	// account rounding and overflow) to the precision of the resulting type.
1475	// Same ranks between signed and unsigned types are resolved earlier, so both
1476	// types are either signed or both unsigned at this point.
1477	unsigned LHSTyRank = GetFixedPointRank(Ty: LHSTy);
1478	unsigned RHSTyRank = GetFixedPointRank(Ty: RHSTy);
1479
1480	QualType ResultTy = LHSTyRank > RHSTyRank ? LHSTy : RHSTy;
1481
1482	if (LHSTy->isSaturatedFixedPointType() || RHSTy->isSaturatedFixedPointType())
1483	ResultTy = S.Context.getCorrespondingSaturatedType(Ty: ResultTy);
1484
1485	return ResultTy;
1486	}
1487
1488	/// Check that the usual arithmetic conversions can be performed on this pair of
1489	/// expressions that might be of enumeration type.
1490	static void checkEnumArithmeticConversions(Sema &S, Expr *LHS, Expr *RHS,
1491	SourceLocation Loc,
1492	Sema::ArithConvKind ACK) {
1493	// C++2a [expr.arith.conv]p1:
1494	// If one operand is of enumeration type and the other operand is of a
1495	// different enumeration type or a floating-point type, this behavior is
1496	// deprecated ([depr.arith.conv.enum]).
1497	//
1498	// Warn on this in all language modes. Produce a deprecation warning in C++20.
1499	// Eventually we will presumably reject these cases (in C++23 onwards?).
1500	QualType L = LHS->getType(), R = RHS->getType();
1501	bool LEnum = L->isUnscopedEnumerationType(),
1502	REnum = R->isUnscopedEnumerationType();
1503	bool IsCompAssign = ACK == Sema::ACK_CompAssign;
1504	if ((!IsCompAssign && LEnum && R->isFloatingType()) ||
1505	(REnum && L->isFloatingType())) {
1506	S.Diag(Loc, S.getLangOpts().CPlusPlus26
1507	? diag::err_arith_conv_enum_float_cxx26
1508	: S.getLangOpts().CPlusPlus20
1509	? diag::warn_arith_conv_enum_float_cxx20
1510	: diag::warn_arith_conv_enum_float)
1511	<< LHS->getSourceRange() << RHS->getSourceRange() << (int)ACK << LEnum
1512	<< L << R;
1513	} else if (!IsCompAssign && LEnum && REnum &&
1514	!S.Context.hasSameUnqualifiedType(T1: L, T2: R)) {
1515	unsigned DiagID;
1516	// In C++ 26, usual arithmetic conversions between 2 different enum types
1517	// are ill-formed.
1518	if (S.getLangOpts().CPlusPlus26)
1519	DiagID = diag::err_conv_mixed_enum_types_cxx26;
1520	else if (!L->castAs<EnumType>()->getDecl()->hasNameForLinkage() ||
1521	!R->castAs<EnumType>()->getDecl()->hasNameForLinkage()) {
1522	// If either enumeration type is unnamed, it's less likely that the
1523	// user cares about this, but this situation is still deprecated in
1524	// C++2a. Use a different warning group.
1525	DiagID = S.getLangOpts().CPlusPlus20
1526	? diag::warn_arith_conv_mixed_anon_enum_types_cxx20
1527	: diag::warn_arith_conv_mixed_anon_enum_types;
1528	} else if (ACK == Sema::ACK_Conditional) {
1529	// Conditional expressions are separated out because they have
1530	// historically had a different warning flag.
1531	DiagID = S.getLangOpts().CPlusPlus20
1532	? diag::warn_conditional_mixed_enum_types_cxx20
1533	: diag::warn_conditional_mixed_enum_types;
1534	} else if (ACK == Sema::ACK_Comparison) {
1535	// Comparison expressions are separated out because they have
1536	// historically had a different warning flag.
1537	DiagID = S.getLangOpts().CPlusPlus20
1538	? diag::warn_comparison_mixed_enum_types_cxx20
1539	: diag::warn_comparison_mixed_enum_types;
1540	} else {
1541	DiagID = S.getLangOpts().CPlusPlus20
1542	? diag::warn_arith_conv_mixed_enum_types_cxx20
1543	: diag::warn_arith_conv_mixed_enum_types;
1544	}
1545	S.Diag(Loc, DiagID) << LHS->getSourceRange() << RHS->getSourceRange()
1546	<< (int)ACK << L << R;
1547	}
1548	}
1549
1550	/// UsualArithmeticConversions - Performs various conversions that are common to
1551	/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this
1552	/// routine returns the first non-arithmetic type found. The client is
1553	/// responsible for emitting appropriate error diagnostics.
1554	QualType Sema::UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS,
1555	SourceLocation Loc,
1556	ArithConvKind ACK) {
1557	checkEnumArithmeticConversions(S&: *this, LHS: LHS.get(), RHS: RHS.get(), Loc, ACK);
1558
1559	if (ACK != ACK_CompAssign) {
1560	LHS = UsualUnaryConversions(E: LHS.get());
1561	if (LHS.isInvalid())
1562	return QualType();
1563	}
1564
1565	RHS = UsualUnaryConversions(E: RHS.get());
1566	if (RHS.isInvalid())
1567	return QualType();
1568
1569	// For conversion purposes, we ignore any qualifiers.
1570	// For example, "const float" and "float" are equivalent.
1571	QualType LHSType = LHS.get()->getType().getUnqualifiedType();
1572	QualType RHSType = RHS.get()->getType().getUnqualifiedType();
1573
1574	// For conversion purposes, we ignore any atomic qualifier on the LHS.
1575	if (const AtomicType *AtomicLHS = LHSType->getAs<AtomicType>())
1576	LHSType = AtomicLHS->getValueType();
1577
1578	// If both types are identical, no conversion is needed.
1579	if (Context.hasSameType(T1: LHSType, T2: RHSType))
1580	return Context.getCommonSugaredType(X: LHSType, Y: RHSType);
1581
1582	// If either side is a non-arithmetic type (e.g. a pointer), we are done.
1583	// The caller can deal with this (e.g. pointer + int).
1584	if (!LHSType->isArithmeticType() || !RHSType->isArithmeticType())
1585	return QualType();
1586
1587	// Apply unary and bitfield promotions to the LHS's type.
1588	QualType LHSUnpromotedType = LHSType;
1589	if (Context.isPromotableIntegerType(T: LHSType))
1590	LHSType = Context.getPromotedIntegerType(PromotableType: LHSType);
1591	QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(E: LHS.get());
1592	if (!LHSBitfieldPromoteTy.isNull())
1593	LHSType = LHSBitfieldPromoteTy;
1594	if (LHSType != LHSUnpromotedType && ACK != ACK_CompAssign)
1595	LHS = ImpCastExprToType(E: LHS.get(), Type: LHSType, CK: CK_IntegralCast);
1596
1597	// If both types are identical, no conversion is needed.
1598	if (Context.hasSameType(T1: LHSType, T2: RHSType))
1599	return Context.getCommonSugaredType(X: LHSType, Y: RHSType);
1600
1601	// At this point, we have two different arithmetic types.
1602
1603	// Diagnose attempts to convert between __ibm128, __float128 and long double
1604	// where such conversions currently can't be handled.
1605	if (unsupportedTypeConversion(S: *this, LHSType, RHSType))
1606	return QualType();
1607
1608	// Handle complex types first (C99 6.3.1.8p1).
1609	if (LHSType->isComplexType() || RHSType->isComplexType())
1610	return handleComplexConversion(S&: *this, LHS, RHS, LHSType, RHSType,
1611	IsCompAssign: ACK == ACK_CompAssign);
1612
1613	// Now handle "real" floating types (i.e. float, double, long double).
1614	if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType())
1615	return handleFloatConversion(S&: *this, LHS, RHS, LHSType, RHSType,
1616	IsCompAssign: ACK == ACK_CompAssign);
1617
1618	// Handle GCC complex int extension.
1619	if (LHSType->isComplexIntegerType() || RHSType->isComplexIntegerType())
1620	return handleComplexIntConversion(S&: *this, LHS, RHS, LHSType, RHSType,
1621	IsCompAssign: ACK == ACK_CompAssign);
1622
1623	if (LHSType->isFixedPointType() || RHSType->isFixedPointType())
1624	return handleFixedPointConversion(S&: *this, LHSTy: LHSType, RHSTy: RHSType);
1625
1626	// Finally, we have two differing integer types.
1627	return handleIntegerConversion<doIntegralCast, doIntegralCast>
1628	(S&: *this, LHS, RHS, LHSType, RHSType, IsCompAssign: ACK == ACK_CompAssign);
1629	}
1630
1631	//===----------------------------------------------------------------------===//
1632	// Semantic Analysis for various Expression Types
1633	//===----------------------------------------------------------------------===//
1634
1635
1636	ExprResult Sema::ActOnGenericSelectionExpr(
1637	SourceLocation KeyLoc, SourceLocation DefaultLoc, SourceLocation RParenLoc,
1638	bool PredicateIsExpr, void *ControllingExprOrType,
1639	ArrayRef<ParsedType> ArgTypes, ArrayRef<Expr *> ArgExprs) {
1640	unsigned NumAssocs = ArgTypes.size();
1641	assert(NumAssocs == ArgExprs.size());
1642
1643	TypeSourceInfo **Types = new TypeSourceInfo*[NumAssocs];
1644	for (unsigned i = 0; i < NumAssocs; ++i) {
1645	if (ArgTypes[i])
1646	(void) GetTypeFromParser(Ty: ArgTypes[i], TInfo: &Types[i]);
1647	else
1648	Types[i] = nullptr;
1649	}
1650
1651	// If we have a controlling type, we need to convert it from a parsed type
1652	// into a semantic type and then pass that along.
1653	if (!PredicateIsExpr) {
1654	TypeSourceInfo *ControllingType;
1655	(void)GetTypeFromParser(Ty: ParsedType::getFromOpaquePtr(P: ControllingExprOrType),
1656	TInfo: &ControllingType);
1657	assert(ControllingType && "couldn't get the type out of the parser");
1658	ControllingExprOrType = ControllingType;
1659	}
1660
1661	ExprResult ER = CreateGenericSelectionExpr(
1662	KeyLoc, DefaultLoc, RParenLoc, PredicateIsExpr, ControllingExprOrType,
1663	Types: llvm::ArrayRef(Types, NumAssocs), Exprs: ArgExprs);
1664	delete [] Types;
1665	return ER;
1666	}
1667
1668	ExprResult Sema::CreateGenericSelectionExpr(
1669	SourceLocation KeyLoc, SourceLocation DefaultLoc, SourceLocation RParenLoc,
1670	bool PredicateIsExpr, void *ControllingExprOrType,
1671	ArrayRef<TypeSourceInfo *> Types, ArrayRef<Expr *> Exprs) {
1672	unsigned NumAssocs = Types.size();
1673	assert(NumAssocs == Exprs.size());
1674	assert(ControllingExprOrType &&
1675	"Must have either a controlling expression or a controlling type");
1676
1677	Expr *ControllingExpr = nullptr;
1678	TypeSourceInfo *ControllingType = nullptr;
1679	if (PredicateIsExpr) {
1680	// Decay and strip qualifiers for the controlling expression type, and
1681	// handle placeholder type replacement. See committee discussion from WG14
1682	// DR423.
1683	EnterExpressionEvaluationContext Unevaluated(
1684	*this, Sema::ExpressionEvaluationContext::Unevaluated);
1685	ExprResult R = DefaultFunctionArrayLvalueConversion(
1686	E: reinterpret_cast<Expr *>(ControllingExprOrType));
1687	if (R.isInvalid())
1688	return ExprError();
1689	ControllingExpr = R.get();
1690	} else {
1691	// The extension form uses the type directly rather than converting it.
1692	ControllingType = reinterpret_cast<TypeSourceInfo *>(ControllingExprOrType);
1693	if (!ControllingType)
1694	return ExprError();
1695	}
1696
1697	bool TypeErrorFound = false,
1698	IsResultDependent = ControllingExpr
1699	? ControllingExpr->isTypeDependent()
1700	: ControllingType->getType()->isDependentType(),
1701	ContainsUnexpandedParameterPack =
1702	ControllingExpr
1703	? ControllingExpr->containsUnexpandedParameterPack()
1704	: ControllingType->getType()->containsUnexpandedParameterPack();
1705
1706	// The controlling expression is an unevaluated operand, so side effects are
1707	// likely unintended.
1708	if (!inTemplateInstantiation() && !IsResultDependent && ControllingExpr &&
1709	ControllingExpr->HasSideEffects(Context, false))
1710	Diag(ControllingExpr->getExprLoc(),
1711	diag::warn_side_effects_unevaluated_context);
1712
1713	for (unsigned i = 0; i < NumAssocs; ++i) {
1714	if (Exprs[i]->containsUnexpandedParameterPack())
1715	ContainsUnexpandedParameterPack = true;
1716
1717	if (Types[i]) {
1718	if (Types[i]->getType()->containsUnexpandedParameterPack())
1719	ContainsUnexpandedParameterPack = true;
1720
1721	if (Types[i]->getType()->isDependentType()) {
1722	IsResultDependent = true;
1723	} else {
1724	// We relax the restriction on use of incomplete types and non-object
1725	// types with the type-based extension of _Generic. Allowing incomplete
1726	// objects means those can be used as "tags" for a type-safe way to map
1727	// to a value. Similarly, matching on function types rather than
1728	// function pointer types can be useful. However, the restriction on VM
1729	// types makes sense to retain as there are open questions about how
1730	// the selection can be made at compile time.
1731	//
1732	// C11 6.5.1.1p2 "The type name in a generic association shall specify a
1733	// complete object type other than a variably modified type."
1734	unsigned D = 0;
1735	if (ControllingExpr && Types[i]->getType()->isIncompleteType())
1736	D = diag::err_assoc_type_incomplete;
1737	else if (ControllingExpr && !Types[i]->getType()->isObjectType())
1738	D = diag::err_assoc_type_nonobject;
1739	else if (Types[i]->getType()->isVariablyModifiedType())
1740	D = diag::err_assoc_type_variably_modified;
1741	else if (ControllingExpr) {
1742	// Because the controlling expression undergoes lvalue conversion,
1743	// array conversion, and function conversion, an association which is
1744	// of array type, function type, or is qualified can never be
1745	// reached. We will warn about this so users are less surprised by
1746	// the unreachable association. However, we don't have to handle
1747	// function types; that's not an object type, so it's handled above.
1748	//
1749	// The logic is somewhat different for C++ because C++ has different
1750	// lvalue to rvalue conversion rules than C. [conv.lvalue]p1 says,
1751	// If T is a non-class type, the type of the prvalue is the cv-
1752	// unqualified version of T. Otherwise, the type of the prvalue is T.
1753	// The result of these rules is that all qualified types in an
1754	// association in C are unreachable, and in C++, only qualified non-
1755	// class types are unreachable.
1756	//
1757	// NB: this does not apply when the first operand is a type rather
1758	// than an expression, because the type form does not undergo
1759	// conversion.
1760	unsigned Reason = 0;
1761	QualType QT = Types[i]->getType();
1762	if (QT->isArrayType())
1763	Reason = 1;
1764	else if (QT.hasQualifiers() &&
1765	(!LangOpts.CPlusPlus || !QT->isRecordType()))
1766	Reason = 2;
1767
1768	if (Reason)
1769	Diag(Types[i]->getTypeLoc().getBeginLoc(),
1770	diag::warn_unreachable_association)
1771	<< QT << (Reason - 1);
1772	}
1773
1774	if (D != 0) {
1775	Diag(Loc: Types[i]->getTypeLoc().getBeginLoc(), DiagID: D)
1776	<< Types[i]->getTypeLoc().getSourceRange()
1777	<< Types[i]->getType();
1778	TypeErrorFound = true;
1779	}
1780
1781	// C11 6.5.1.1p2 "No two generic associations in the same generic
1782	// selection shall specify compatible types."
1783	for (unsigned j = i+1; j < NumAssocs; ++j)
1784	if (Types[j] && !Types[j]->getType()->isDependentType() &&
1785	Context.typesAreCompatible(T1: Types[i]->getType(),
1786	T2: Types[j]->getType())) {
1787	Diag(Types[j]->getTypeLoc().getBeginLoc(),
1788	diag::err_assoc_compatible_types)
1789	<< Types[j]->getTypeLoc().getSourceRange()
1790	<< Types[j]->getType()
1791	<< Types[i]->getType();
1792	Diag(Types[i]->getTypeLoc().getBeginLoc(),
1793	diag::note_compat_assoc)
1794	<< Types[i]->getTypeLoc().getSourceRange()
1795	<< Types[i]->getType();
1796	TypeErrorFound = true;
1797	}
1798	}
1799	}
1800	}
1801	if (TypeErrorFound)
1802	return ExprError();
1803
1804	// If we determined that the generic selection is result-dependent, don't
1805	// try to compute the result expression.
1806	if (IsResultDependent) {
1807	if (ControllingExpr)
1808	return GenericSelectionExpr::Create(Context, GenericLoc: KeyLoc, ControllingExpr,
1809	AssocTypes: Types, AssocExprs: Exprs, DefaultLoc, RParenLoc,
1810	ContainsUnexpandedParameterPack);
1811	return GenericSelectionExpr::Create(Context, GenericLoc: KeyLoc, ControllingType, AssocTypes: Types,
1812	AssocExprs: Exprs, DefaultLoc, RParenLoc,
1813	ContainsUnexpandedParameterPack);
1814	}
1815
1816	SmallVector<unsigned, 1> CompatIndices;
1817	unsigned DefaultIndex = -1U;
1818	// Look at the canonical type of the controlling expression in case it was a
1819	// deduced type like __auto_type. However, when issuing diagnostics, use the
1820	// type the user wrote in source rather than the canonical one.
1821	for (unsigned i = 0; i < NumAssocs; ++i) {
1822	if (!Types[i])
1823	DefaultIndex = i;
1824	else if (ControllingExpr &&
1825	Context.typesAreCompatible(
1826	T1: ControllingExpr->getType().getCanonicalType(),
1827	T2: Types[i]->getType()))
1828	CompatIndices.push_back(Elt: i);
1829	else if (ControllingType &&
1830	Context.typesAreCompatible(
1831	T1: ControllingType->getType().getCanonicalType(),
1832	T2: Types[i]->getType()))
1833	CompatIndices.push_back(Elt: i);
1834	}
1835
1836	auto GetControllingRangeAndType = [](Expr *ControllingExpr,
1837	TypeSourceInfo *ControllingType) {
1838	// We strip parens here because the controlling expression is typically
1839	// parenthesized in macro definitions.
1840	if (ControllingExpr)
1841	ControllingExpr = ControllingExpr->IgnoreParens();
1842
1843	SourceRange SR = ControllingExpr
1844	? ControllingExpr->getSourceRange()
1845	: ControllingType->getTypeLoc().getSourceRange();
1846	QualType QT = ControllingExpr ? ControllingExpr->getType()
1847	: ControllingType->getType();
1848
1849	return std::make_pair(SR, QT);
1850	};
1851
1852	// C11 6.5.1.1p2 "The controlling expression of a generic selection shall have
1853	// type compatible with at most one of the types named in its generic
1854	// association list."
1855	if (CompatIndices.size() > 1) {
1856	auto P = GetControllingRangeAndType(ControllingExpr, ControllingType);
1857	SourceRange SR = P.first;
1858	Diag(SR.getBegin(), diag::err_generic_sel_multi_match)
1859	<< SR << P.second << (unsigned)CompatIndices.size();
1860	for (unsigned I : CompatIndices) {
1861	Diag(Types[I]->getTypeLoc().getBeginLoc(),
1862	diag::note_compat_assoc)
1863	<< Types[I]->getTypeLoc().getSourceRange()
1864	<< Types[I]->getType();
1865	}
1866	return ExprError();
1867	}
1868
1869	// C11 6.5.1.1p2 "If a generic selection has no default generic association,
1870	// its controlling expression shall have type compatible with exactly one of
1871	// the types named in its generic association list."
1872	if (DefaultIndex == -1U && CompatIndices.size() == 0) {
1873	auto P = GetControllingRangeAndType(ControllingExpr, ControllingType);
1874	SourceRange SR = P.first;
1875	Diag(SR.getBegin(), diag::err_generic_sel_no_match) << SR << P.second;
1876	return ExprError();
1877	}
1878
1879	// C11 6.5.1.1p3 "If a generic selection has a generic association with a
1880	// type name that is compatible with the type of the controlling expression,
1881	// then the result expression of the generic selection is the expression
1882	// in that generic association. Otherwise, the result expression of the
1883	// generic selection is the expression in the default generic association."
1884	unsigned ResultIndex =
1885	CompatIndices.size() ? CompatIndices[0] : DefaultIndex;
1886
1887	if (ControllingExpr) {
1888	return GenericSelectionExpr::Create(
1889	Context, GenericLoc: KeyLoc, ControllingExpr, AssocTypes: Types, AssocExprs: Exprs, DefaultLoc, RParenLoc,
1890	ContainsUnexpandedParameterPack, ResultIndex);
1891	}
1892	return GenericSelectionExpr::Create(
1893	Context, GenericLoc: KeyLoc, ControllingType, AssocTypes: Types, AssocExprs: Exprs, DefaultLoc, RParenLoc,
1894	ContainsUnexpandedParameterPack, ResultIndex);
1895	}
1896
1897	static PredefinedIdentKind getPredefinedExprKind(tok::TokenKind Kind) {
1898	switch (Kind) {
1899	default:
1900	llvm_unreachable("unexpected TokenKind");
1901	case tok::kw___func__:
1902	return PredefinedIdentKind::Func; // [C99 6.4.2.2]
1903	case tok::kw___FUNCTION__:
1904	return PredefinedIdentKind::Function;
1905	case tok::kw___FUNCDNAME__:
1906	return PredefinedIdentKind::FuncDName; // [MS]
1907	case tok::kw___FUNCSIG__:
1908	return PredefinedIdentKind::FuncSig; // [MS]
1909	case tok::kw_L__FUNCTION__:
1910	return PredefinedIdentKind::LFunction; // [MS]
1911	case tok::kw_L__FUNCSIG__:
1912	return PredefinedIdentKind::LFuncSig; // [MS]
1913	case tok::kw___PRETTY_FUNCTION__:
1914	return PredefinedIdentKind::PrettyFunction; // [GNU]
1915	}
1916	}
1917
1918	/// getPredefinedExprDecl - Returns Decl of a given DeclContext that can be used
1919	/// to determine the value of a PredefinedExpr. This can be either a
1920	/// block, lambda, captured statement, function, otherwise a nullptr.
1921	static Decl *getPredefinedExprDecl(DeclContext *DC) {
1922	while (DC && !isa<BlockDecl, CapturedDecl, FunctionDecl, ObjCMethodDecl>(Val: DC))
1923	DC = DC->getParent();
1924	return cast_or_null<Decl>(Val: DC);
1925	}
1926
1927	/// getUDSuffixLoc - Create a SourceLocation for a ud-suffix, given the
1928	/// location of the token and the offset of the ud-suffix within it.
1929	static SourceLocation getUDSuffixLoc(Sema &S, SourceLocation TokLoc,
1930	unsigned Offset) {
1931	return Lexer::AdvanceToTokenCharacter(TokStart: TokLoc, Characters: Offset, SM: S.getSourceManager(),
1932	LangOpts: S.getLangOpts());
1933	}
1934
1935	/// BuildCookedLiteralOperatorCall - A user-defined literal was found. Look up
1936	/// the corresponding cooked (non-raw) literal operator, and build a call to it.
1937	static ExprResult BuildCookedLiteralOperatorCall(Sema &S, Scope *Scope,
1938	IdentifierInfo *UDSuffix,
1939	SourceLocation UDSuffixLoc,
1940	ArrayRef<Expr*> Args,
1941	SourceLocation LitEndLoc) {
1942	assert(Args.size() <= 2 && "too many arguments for literal operator");
1943
1944	QualType ArgTy[2];
1945	for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) {
1946	ArgTy[ArgIdx] = Args[ArgIdx]->getType();
1947	if (ArgTy[ArgIdx]->isArrayType())
1948	ArgTy[ArgIdx] = S.Context.getArrayDecayedType(T: ArgTy[ArgIdx]);
1949	}
1950
1951	DeclarationName OpName =
1952	S.Context.DeclarationNames.getCXXLiteralOperatorName(II: UDSuffix);
1953	DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
1954	OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
1955
1956	LookupResult R(S, OpName, UDSuffixLoc, Sema::LookupOrdinaryName);
1957	if (S.LookupLiteralOperator(S: Scope, R, ArgTys: llvm::ArrayRef(ArgTy, Args.size()),
1958	/*AllowRaw*/ false, /*AllowTemplate*/ false,
1959	/*AllowStringTemplatePack*/ AllowStringTemplate: false,
1960	/*DiagnoseMissing*/ true) == Sema::LOLR_Error)
1961	return ExprError();
1962
1963	return S.BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args, LitEndLoc);
1964	}
1965
1966	ExprResult Sema::ActOnUnevaluatedStringLiteral(ArrayRef<Token> StringToks) {
1967	// StringToks needs backing storage as it doesn't hold array elements itself
1968	std::vector<Token> ExpandedToks;
1969	if (getLangOpts().MicrosoftExt)
1970	StringToks = ExpandedToks = ExpandFunctionLocalPredefinedMacros(Toks: StringToks);
1971
1972	StringLiteralParser Literal(StringToks, PP,
1973	StringLiteralEvalMethod::Unevaluated);
1974	if (Literal.hadError)
1975	return ExprError();
1976
1977	SmallVector<SourceLocation, 4> StringTokLocs;
1978	for (const Token &Tok : StringToks)
1979	StringTokLocs.push_back(Elt: Tok.getLocation());
1980
1981	StringLiteral *Lit = StringLiteral::Create(
1982	Ctx: Context, Str: Literal.GetString(), Kind: StringLiteralKind::Unevaluated, Pascal: false, Ty: {},
1983	Loc: &StringTokLocs[0], NumConcatenated: StringTokLocs.size());
1984
1985	if (!Literal.getUDSuffix().empty()) {
1986	SourceLocation UDSuffixLoc =
1987	getUDSuffixLoc(S&: *this, TokLoc: StringTokLocs[Literal.getUDSuffixToken()],
1988	Offset: Literal.getUDSuffixOffset());
1989	return ExprError(Diag(UDSuffixLoc, diag::err_invalid_string_udl));
1990	}
1991
1992	return Lit;
1993	}
1994
1995	std::vector<Token>
1996	Sema::ExpandFunctionLocalPredefinedMacros(ArrayRef<Token> Toks) {
1997	// MSVC treats some predefined identifiers (e.g. __FUNCTION__) as function
1998	// local macros that expand to string literals that may be concatenated.
1999	// These macros are expanded here (in Sema), because StringLiteralParser
2000	// (in Lex) doesn't know the enclosing function (because it hasn't been
2001	// parsed yet).
2002	assert(getLangOpts().MicrosoftExt);
2003
2004	// Note: Although function local macros are defined only inside functions,
2005	// we ensure a valid `CurrentDecl` even outside of a function. This allows
2006	// expansion of macros into empty string literals without additional checks.
2007	Decl *CurrentDecl = getPredefinedExprDecl(DC: CurContext);
2008	if (!CurrentDecl)
2009	CurrentDecl = Context.getTranslationUnitDecl();
2010
2011	std::vector<Token> ExpandedToks;
2012	ExpandedToks.reserve(n: Toks.size());
2013	for (const Token &Tok : Toks) {
2014	if (!isFunctionLocalStringLiteralMacro(K: Tok.getKind(), LO: getLangOpts())) {
2015	assert(tok::isStringLiteral(Tok.getKind()));
2016	ExpandedToks.emplace_back(args: Tok);
2017	continue;
2018	}
2019	if (isa<TranslationUnitDecl>(CurrentDecl))
2020	Diag(Tok.getLocation(), diag::ext_predef_outside_function);
2021	// Stringify predefined expression
2022	Diag(Tok.getLocation(), diag::ext_string_literal_from_predefined)
2023	<< Tok.getKind();
2024	SmallString<64> Str;
2025	llvm::raw_svector_ostream OS(Str);
2026	Token &Exp = ExpandedToks.emplace_back();
2027	Exp.startToken();
2028	if (Tok.getKind() == tok::kw_L__FUNCTION__ ||
2029	Tok.getKind() == tok::kw_L__FUNCSIG__) {
2030	OS << 'L';
2031	Exp.setKind(tok::wide_string_literal);
2032	} else {
2033	Exp.setKind(tok::string_literal);
2034	}
2035	OS << '"'
2036	<< Lexer::Stringify(Str: PredefinedExpr::ComputeName(
2037	IK: getPredefinedExprKind(Kind: Tok.getKind()), CurrentDecl))
2038	<< '"';
2039	PP.CreateString(Str: OS.str(), Tok&: Exp, ExpansionLocStart: Tok.getLocation(), ExpansionLocEnd: Tok.getEndLoc());
2040	}
2041	return ExpandedToks;
2042	}
2043
2044	/// ActOnStringLiteral - The specified tokens were lexed as pasted string
2045	/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string
2046	/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from
2047	/// multiple tokens. However, the common case is that StringToks points to one
2048	/// string.
2049	///
2050	ExprResult
2051	Sema::ActOnStringLiteral(ArrayRef<Token> StringToks, Scope *UDLScope) {
2052	assert(!StringToks.empty() && "Must have at least one string!");
2053
2054	// StringToks needs backing storage as it doesn't hold array elements itself
2055	std::vector<Token> ExpandedToks;
2056	if (getLangOpts().MicrosoftExt)
2057	StringToks = ExpandedToks = ExpandFunctionLocalPredefinedMacros(Toks: StringToks);
2058
2059	StringLiteralParser Literal(StringToks, PP);
2060	if (Literal.hadError)
2061	return ExprError();
2062
2063	SmallVector<SourceLocation, 4> StringTokLocs;
2064	for (const Token &Tok : StringToks)
2065	StringTokLocs.push_back(Elt: Tok.getLocation());
2066
2067	QualType CharTy = Context.CharTy;
2068	StringLiteralKind Kind = StringLiteralKind::Ordinary;
2069	if (Literal.isWide()) {
2070	CharTy = Context.getWideCharType();
2071	Kind = StringLiteralKind::Wide;
2072	} else if (Literal.isUTF8()) {
2073	if (getLangOpts().Char8)
2074	CharTy = Context.Char8Ty;
2075	Kind = StringLiteralKind::UTF8;
2076	} else if (Literal.isUTF16()) {
2077	CharTy = Context.Char16Ty;
2078	Kind = StringLiteralKind::UTF16;
2079	} else if (Literal.isUTF32()) {
2080	CharTy = Context.Char32Ty;
2081	Kind = StringLiteralKind::UTF32;
2082	} else if (Literal.isPascal()) {
2083	CharTy = Context.UnsignedCharTy;
2084	}
2085
2086	// Warn on initializing an array of char from a u8 string literal; this
2087	// becomes ill-formed in C++2a.
2088	if (getLangOpts().CPlusPlus && !getLangOpts().CPlusPlus20 &&
2089	!getLangOpts().Char8 && Kind == StringLiteralKind::UTF8) {
2090	Diag(StringTokLocs.front(), diag::warn_cxx20_compat_utf8_string);
2091
2092	// Create removals for all 'u8' prefixes in the string literal(s). This
2093	// ensures C++2a compatibility (but may change the program behavior when
2094	// built by non-Clang compilers for which the execution character set is
2095	// not always UTF-8).
2096	auto RemovalDiag = PDiag(diag::note_cxx20_compat_utf8_string_remove_u8);
2097	SourceLocation RemovalDiagLoc;
2098	for (const Token &Tok : StringToks) {
2099	if (Tok.getKind() == tok::utf8_string_literal) {
2100	if (RemovalDiagLoc.isInvalid())
2101	RemovalDiagLoc = Tok.getLocation();
2102	RemovalDiag << FixItHint::CreateRemoval(RemoveRange: CharSourceRange::getCharRange(
2103	B: Tok.getLocation(),
2104	E: Lexer::AdvanceToTokenCharacter(TokStart: Tok.getLocation(), Characters: 2,
2105	SM: getSourceManager(), LangOpts: getLangOpts())));
2106	}
2107	}
2108	Diag(RemovalDiagLoc, RemovalDiag);
2109	}
2110
2111	QualType StrTy =
2112	Context.getStringLiteralArrayType(EltTy: CharTy, Length: Literal.GetNumStringChars());
2113
2114	// Pass &StringTokLocs[0], StringTokLocs.size() to factory!
2115	StringLiteral *Lit = StringLiteral::Create(Ctx: Context, Str: Literal.GetString(),
2116	Kind, Pascal: Literal.Pascal, Ty: StrTy,
2117	Loc: &StringTokLocs[0],
2118	NumConcatenated: StringTokLocs.size());
2119	if (Literal.getUDSuffix().empty())
2120	return Lit;
2121
2122	// We're building a user-defined literal.
2123	IdentifierInfo *UDSuffix = &Context.Idents.get(Name: Literal.getUDSuffix());
2124	SourceLocation UDSuffixLoc =
2125	getUDSuffixLoc(S&: *this, TokLoc: StringTokLocs[Literal.getUDSuffixToken()],
2126	Offset: Literal.getUDSuffixOffset());
2127
2128	// Make sure we're allowed user-defined literals here.
2129	if (!UDLScope)
2130	return ExprError(Diag(UDSuffixLoc, diag::err_invalid_string_udl));
2131
2132	// C++11 [lex.ext]p5: The literal L is treated as a call of the form
2133	// operator "" X (str, len)
2134	QualType SizeType = Context.getSizeType();
2135
2136	DeclarationName OpName =
2137	Context.DeclarationNames.getCXXLiteralOperatorName(II: UDSuffix);
2138	DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
2139	OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
2140
2141	QualType ArgTy[] = {
2142	Context.getArrayDecayedType(T: StrTy), SizeType
2143	};
2144
2145	LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName);
2146	switch (LookupLiteralOperator(S: UDLScope, R, ArgTys: ArgTy,
2147	/*AllowRaw*/ false, /*AllowTemplate*/ true,
2148	/*AllowStringTemplatePack*/ AllowStringTemplate: true,
2149	/*DiagnoseMissing*/ true, StringLit: Lit)) {
2150
2151	case LOLR_Cooked: {
2152	llvm::APInt Len(Context.getIntWidth(T: SizeType), Literal.GetNumStringChars());
2153	IntegerLiteral *LenArg = IntegerLiteral::Create(C: Context, V: Len, type: SizeType,
2154	l: StringTokLocs[0]);
2155	Expr *Args[] = { Lit, LenArg };
2156
2157	return BuildLiteralOperatorCall(R, OpNameInfo, Args, StringTokLocs.back());
2158	}
2159
2160	case LOLR_Template: {
2161	TemplateArgumentListInfo ExplicitArgs;
2162	TemplateArgument Arg(Lit);
2163	TemplateArgumentLocInfo ArgInfo(Lit);
2164	ExplicitArgs.addArgument(Loc: TemplateArgumentLoc(Arg, ArgInfo));
2165	return BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args: std::nullopt,
2166	LitEndLoc: StringTokLocs.back(), ExplicitTemplateArgs: &ExplicitArgs);
2167	}
2168
2169	case LOLR_StringTemplatePack: {
2170	TemplateArgumentListInfo ExplicitArgs;
2171
2172	unsigned CharBits = Context.getIntWidth(T: CharTy);
2173	bool CharIsUnsigned = CharTy->isUnsignedIntegerType();
2174	llvm::APSInt Value(CharBits, CharIsUnsigned);
2175
2176	TemplateArgument TypeArg(CharTy);
2177	TemplateArgumentLocInfo TypeArgInfo(Context.getTrivialTypeSourceInfo(T: CharTy));
2178	ExplicitArgs.addArgument(Loc: TemplateArgumentLoc(TypeArg, TypeArgInfo));
2179
2180	for (unsigned I = 0, N = Lit->getLength(); I != N; ++I) {
2181	Value = Lit->getCodeUnit(i: I);
2182	TemplateArgument Arg(Context, Value, CharTy);
2183	TemplateArgumentLocInfo ArgInfo;
2184	ExplicitArgs.addArgument(Loc: TemplateArgumentLoc(Arg, ArgInfo));
2185	}
2186	return BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args: std::nullopt,
2187	LitEndLoc: StringTokLocs.back(), ExplicitTemplateArgs: &ExplicitArgs);
2188	}
2189	case LOLR_Raw:
2190	case LOLR_ErrorNoDiagnostic:
2191	llvm_unreachable("unexpected literal operator lookup result");
2192	case LOLR_Error:
2193	return ExprError();
2194	}
2195	llvm_unreachable("unexpected literal operator lookup result");
2196	}
2197
2198	DeclRefExpr *
2199	Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
2200	SourceLocation Loc,
2201	const CXXScopeSpec *SS) {
2202	DeclarationNameInfo NameInfo(D->getDeclName(), Loc);
2203	return BuildDeclRefExpr(D, Ty, VK, NameInfo, SS);
2204	}
2205
2206	DeclRefExpr *
2207	Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
2208	const DeclarationNameInfo &NameInfo,
2209	const CXXScopeSpec *SS, NamedDecl *FoundD,
2210	SourceLocation TemplateKWLoc,
2211	const TemplateArgumentListInfo *TemplateArgs) {
2212	NestedNameSpecifierLoc NNS =
2213	SS ? SS->getWithLocInContext(Context) : NestedNameSpecifierLoc();
2214	return BuildDeclRefExpr(D, Ty, VK, NameInfo, NNS, FoundD, TemplateKWLoc,
2215	TemplateArgs);
2216	}
2217
2218	// CUDA/HIP: Check whether a captured reference variable is referencing a
2219	// host variable in a device or host device lambda.
2220	static bool isCapturingReferenceToHostVarInCUDADeviceLambda(const Sema &S,
2221	VarDecl *VD) {
2222	if (!S.getLangOpts().CUDA || !VD->hasInit())
2223	return false;
2224	assert(VD->getType()->isReferenceType());
2225
2226	// Check whether the reference variable is referencing a host variable.
2227	auto *DRE = dyn_cast<DeclRefExpr>(Val: VD->getInit());
2228	if (!DRE)
2229	return false;
2230	auto *Referee = dyn_cast<VarDecl>(Val: DRE->getDecl());
2231	if (!Referee || !Referee->hasGlobalStorage() ||
2232	Referee->hasAttr<CUDADeviceAttr>())
2233	return false;
2234
2235	// Check whether the current function is a device or host device lambda.
2236	// Check whether the reference variable is a capture by getDeclContext()
2237	// since refersToEnclosingVariableOrCapture() is not ready at this point.
2238	auto *MD = dyn_cast_or_null<CXXMethodDecl>(Val: S.CurContext);
2239	if (MD && MD->getParent()->isLambda() &&
2240	MD->getOverloadedOperator() == OO_Call && MD->hasAttr<CUDADeviceAttr>() &&
2241	VD->getDeclContext() != MD)
2242	return true;
2243
2244	return false;
2245	}
2246
2247	NonOdrUseReason Sema::getNonOdrUseReasonInCurrentContext(ValueDecl *D) {
2248	// A declaration named in an unevaluated operand never constitutes an odr-use.
2249	if (isUnevaluatedContext())
2250	return NOUR_Unevaluated;
2251
2252	// C++2a [basic.def.odr]p4:
2253	// A variable x whose name appears as a potentially-evaluated expression e
2254	// is odr-used by e unless [...] x is a reference that is usable in
2255	// constant expressions.
2256	// CUDA/HIP:
2257	// If a reference variable referencing a host variable is captured in a
2258	// device or host device lambda, the value of the referee must be copied
2259	// to the capture and the reference variable must be treated as odr-use
2260	// since the value of the referee is not known at compile time and must
2261	// be loaded from the captured.
2262	if (VarDecl *VD = dyn_cast<VarDecl>(Val: D)) {
2263	if (VD->getType()->isReferenceType() &&
2264	!(getLangOpts().OpenMP && isOpenMPCapturedDecl(D)) &&
2265	!isCapturingReferenceToHostVarInCUDADeviceLambda(S: *this, VD) &&
2266	VD->isUsableInConstantExpressions(C: Context))
2267	return NOUR_Constant;
2268	}
2269
2270	// All remaining non-variable cases constitute an odr-use. For variables, we
2271	// need to wait and see how the expression is used.
2272	return NOUR_None;
2273	}
2274
2275	/// BuildDeclRefExpr - Build an expression that references a
2276	/// declaration that does not require a closure capture.
2277	DeclRefExpr *
2278	Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
2279	const DeclarationNameInfo &NameInfo,
2280	NestedNameSpecifierLoc NNS, NamedDecl *FoundD,
2281	SourceLocation TemplateKWLoc,
2282	const TemplateArgumentListInfo *TemplateArgs) {
2283	bool RefersToCapturedVariable = isa<VarDecl, BindingDecl>(Val: D) &&
2284	NeedToCaptureVariable(Var: D, Loc: NameInfo.getLoc());
2285
2286	DeclRefExpr *E = DeclRefExpr::Create(
2287	Context, QualifierLoc: NNS, TemplateKWLoc, D, RefersToEnclosingVariableOrCapture: RefersToCapturedVariable, NameInfo, T: Ty,
2288	VK, FoundD, TemplateArgs, NOUR: getNonOdrUseReasonInCurrentContext(D));
2289	MarkDeclRefReferenced(E);
2290
2291	// C++ [except.spec]p17:
2292	// An exception-specification is considered to be needed when:
2293	// - in an expression, the function is the unique lookup result or
2294	// the selected member of a set of overloaded functions.
2295	//
2296	// We delay doing this until after we've built the function reference and
2297	// marked it as used so that:
2298	// a) if the function is defaulted, we get errors from defining it before /
2299	// instead of errors from computing its exception specification, and
2300	// b) if the function is a defaulted comparison, we can use the body we
2301	// build when defining it as input to the exception specification
2302	// computation rather than computing a new body.
2303	if (const auto *FPT = Ty->getAs<FunctionProtoType>()) {
2304	if (isUnresolvedExceptionSpec(ESpecType: FPT->getExceptionSpecType())) {
2305	if (const auto *NewFPT = ResolveExceptionSpec(Loc: NameInfo.getLoc(), FPT))
2306	E->setType(Context.getQualifiedType(NewFPT, Ty.getQualifiers()));
2307	}
2308	}
2309
2310	if (getLangOpts().ObjCWeak && isa<VarDecl>(D) &&
2311	Ty.getObjCLifetime() == Qualifiers::OCL_Weak && !isUnevaluatedContext() &&
2312	!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, E->getBeginLoc()))
2313	getCurFunction()->recordUseOfWeak(E);
2314
2315	const auto *FD = dyn_cast<FieldDecl>(Val: D);
2316	if (const auto *IFD = dyn_cast<IndirectFieldDecl>(Val: D))
2317	FD = IFD->getAnonField();
2318	if (FD) {
2319	UnusedPrivateFields.remove(FD);
2320	// Just in case we're building an illegal pointer-to-member.
2321	if (FD->isBitField())
2322	E->setObjectKind(OK_BitField);
2323	}
2324
2325	// C++ [expr.prim]/8: The expression [...] is a bit-field if the identifier
2326	// designates a bit-field.
2327	if (const auto *BD = dyn_cast<BindingDecl>(Val: D))
2328	if (const auto *BE = BD->getBinding())
2329	E->setObjectKind(BE->getObjectKind());
2330
2331	return E;
2332	}
2333
2334	/// Decomposes the given name into a DeclarationNameInfo, its location, and
2335	/// possibly a list of template arguments.
2336	///
2337	/// If this produces template arguments, it is permitted to call
2338	/// DecomposeTemplateName.
2339	///
2340	/// This actually loses a lot of source location information for
2341	/// non-standard name kinds; we should consider preserving that in
2342	/// some way.
2343	void
2344	Sema::DecomposeUnqualifiedId(const UnqualifiedId &Id,
2345	TemplateArgumentListInfo &Buffer,
2346	DeclarationNameInfo &NameInfo,
2347	const TemplateArgumentListInfo *&TemplateArgs) {
2348	if (Id.getKind() == UnqualifiedIdKind::IK_TemplateId) {
2349	Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc);
2350	Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc);
2351
2352	ASTTemplateArgsPtr TemplateArgsPtr(Id.TemplateId->getTemplateArgs(),
2353	Id.TemplateId->NumArgs);
2354	translateTemplateArguments(In: TemplateArgsPtr, Out&: Buffer);
2355
2356	TemplateName TName = Id.TemplateId->Template.get();
2357	SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc;
2358	NameInfo = Context.getNameForTemplate(Name: TName, NameLoc: TNameLoc);
2359	TemplateArgs = &Buffer;
2360	} else {
2361	NameInfo = GetNameFromUnqualifiedId(Name: Id);
2362	TemplateArgs = nullptr;
2363	}
2364	}
2365
2366	static void emitEmptyLookupTypoDiagnostic(
2367	const TypoCorrection &TC, Sema &SemaRef, const CXXScopeSpec &SS,
2368	DeclarationName Typo, SourceLocation TypoLoc, ArrayRef<Expr *> Args,
2369	unsigned DiagnosticID, unsigned DiagnosticSuggestID) {
2370	DeclContext *Ctx =
2371	SS.isEmpty() ? nullptr : SemaRef.computeDeclContext(SS, EnteringContext: false);
2372	if (!TC) {
2373	// Emit a special diagnostic for failed member lookups.
2374	// FIXME: computing the declaration context might fail here (?)
2375	if (Ctx)
2376	SemaRef.Diag(TypoLoc, diag::err_no_member) << Typo << Ctx
2377	<< SS.getRange();
2378	else
2379	SemaRef.Diag(Loc: TypoLoc, DiagID: DiagnosticID) << Typo;
2380	return;
2381	}
2382
2383	std::string CorrectedStr = TC.getAsString(LO: SemaRef.getLangOpts());
2384	bool DroppedSpecifier =
2385	TC.WillReplaceSpecifier() && Typo.getAsString() == CorrectedStr;
2386	unsigned NoteID = TC.getCorrectionDeclAs<ImplicitParamDecl>()
2387	? diag::note_implicit_param_decl
2388	: diag::note_previous_decl;
2389	if (!Ctx)
2390	SemaRef.diagnoseTypo(Correction: TC, TypoDiag: SemaRef.PDiag(DiagID: DiagnosticSuggestID) << Typo,
2391	PrevNote: SemaRef.PDiag(DiagID: NoteID));
2392	else
2393	SemaRef.diagnoseTypo(TC, SemaRef.PDiag(diag::err_no_member_suggest)
2394	<< Typo << Ctx << DroppedSpecifier
2395	<< SS.getRange(),
2396	SemaRef.PDiag(NoteID));
2397	}
2398
2399	/// Diagnose a lookup that found results in an enclosing class during error
2400	/// recovery. This usually indicates that the results were found in a dependent
2401	/// base class that could not be searched as part of a template definition.
2402	/// Always issues a diagnostic (though this may be only a warning in MS
2403	/// compatibility mode).
2404	///
2405	/// Return \c true if the error is unrecoverable, or \c false if the caller
2406	/// should attempt to recover using these lookup results.
2407	bool Sema::DiagnoseDependentMemberLookup(const LookupResult &R) {
2408	// During a default argument instantiation the CurContext points
2409	// to a CXXMethodDecl; but we can't apply a this-> fixit inside a
2410	// function parameter list, hence add an explicit check.
2411	bool isDefaultArgument =
2412	!CodeSynthesisContexts.empty() &&
2413	CodeSynthesisContexts.back().Kind ==
2414	CodeSynthesisContext::DefaultFunctionArgumentInstantiation;
2415	const auto *CurMethod = dyn_cast<CXXMethodDecl>(Val: CurContext);
2416	bool isInstance = CurMethod && CurMethod->isInstance() &&
2417	R.getNamingClass() == CurMethod->getParent() &&
2418	!isDefaultArgument;
2419
2420	// There are two ways we can find a class-scope declaration during template
2421	// instantiation that we did not find in the template definition: if it is a
2422	// member of a dependent base class, or if it is declared after the point of
2423	// use in the same class. Distinguish these by comparing the class in which
2424	// the member was found to the naming class of the lookup.
2425	unsigned DiagID = diag::err_found_in_dependent_base;
2426	unsigned NoteID = diag::note_member_declared_at;
2427	if (R.getRepresentativeDecl()->getDeclContext()->Equals(R.getNamingClass())) {
2428	DiagID = getLangOpts().MSVCCompat ? diag::ext_found_later_in_class
2429	: diag::err_found_later_in_class;
2430	} else if (getLangOpts().MSVCCompat) {
2431	DiagID = diag::ext_found_in_dependent_base;
2432	NoteID = diag::note_dependent_member_use;
2433	}
2434
2435	if (isInstance) {
2436	// Give a code modification hint to insert 'this->'.
2437	Diag(Loc: R.getNameLoc(), DiagID)
2438	<< R.getLookupName()
2439	<< FixItHint::CreateInsertion(InsertionLoc: R.getNameLoc(), Code: "this->");
2440	CheckCXXThisCapture(Loc: R.getNameLoc());
2441	} else {
2442	// FIXME: Add a FixItHint to insert 'Base::' or 'Derived::' (assuming
2443	// they're not shadowed).
2444	Diag(Loc: R.getNameLoc(), DiagID) << R.getLookupName();
2445	}
2446
2447	for (const NamedDecl *D : R)
2448	Diag(D->getLocation(), NoteID);
2449
2450	// Return true if we are inside a default argument instantiation
2451	// and the found name refers to an instance member function, otherwise
2452	// the caller will try to create an implicit member call and this is wrong
2453	// for default arguments.
2454	//
2455	// FIXME: Is this special case necessary? We could allow the caller to
2456	// diagnose this.
2457	if (isDefaultArgument && ((*R.begin())->isCXXInstanceMember())) {
2458	Diag(R.getNameLoc(), diag::err_member_call_without_object) << 0;
2459	return true;
2460	}
2461
2462	// Tell the callee to try to recover.
2463	return false;
2464	}
2465
2466	/// Diagnose an empty lookup.
2467	///
2468	/// \return false if new lookup candidates were found
2469	bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
2470	CorrectionCandidateCallback &CCC,
2471	TemplateArgumentListInfo *ExplicitTemplateArgs,
2472	ArrayRef<Expr *> Args, DeclContext *LookupCtx,
2473	TypoExpr **Out) {
2474	DeclarationName Name = R.getLookupName();
2475
2476	unsigned diagnostic = diag::err_undeclared_var_use;
2477	unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest;
2478	if (Name.getNameKind() == DeclarationName::CXXOperatorName ||
2479	Name.getNameKind() == DeclarationName::CXXLiteralOperatorName ||
2480	Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
2481	diagnostic = diag::err_undeclared_use;
2482	diagnostic_suggest = diag::err_undeclared_use_suggest;
2483	}
2484
2485	// If the original lookup was an unqualified lookup, fake an
2486	// unqualified lookup. This is useful when (for example) the
2487	// original lookup would not have found something because it was a
2488	// dependent name.
2489	DeclContext *DC =
2490	LookupCtx ? LookupCtx : (SS.isEmpty() ? CurContext : nullptr);
2491	while (DC) {
2492	if (isa<CXXRecordDecl>(Val: DC)) {
2493	LookupQualifiedName(R, LookupCtx: DC);
2494
2495	if (!R.empty()) {
2496	// Don't give errors about ambiguities in this lookup.
2497	R.suppressDiagnostics();
2498
2499	// If there's a best viable function among the results, only mention
2500	// that one in the notes.
2501	OverloadCandidateSet Candidates(R.getNameLoc(),
2502	OverloadCandidateSet::CSK_Normal);
2503	AddOverloadedCallCandidates(R, ExplicitTemplateArgs, Args, CandidateSet&: Candidates);
2504	OverloadCandidateSet::iterator Best;
2505	if (Candidates.BestViableFunction(S&: *this, Loc: R.getNameLoc(), Best) ==
2506	OR_Success) {
2507	R.clear();
2508	R.addDecl(D: Best->FoundDecl.getDecl(), AS: Best->FoundDecl.getAccess());
2509	R.resolveKind();
2510	}
2511
2512	return DiagnoseDependentMemberLookup(R);
2513	}
2514
2515	R.clear();
2516	}
2517
2518	DC = DC->getLookupParent();
2519	}
2520
2521	// We didn't find anything, so try to correct for a typo.
2522	TypoCorrection Corrected;
2523	if (S && Out) {
2524	SourceLocation TypoLoc = R.getNameLoc();
2525	assert(!ExplicitTemplateArgs &&
2526	"Diagnosing an empty lookup with explicit template args!");
2527	*Out = CorrectTypoDelayed(
2528	Typo: R.getLookupNameInfo(), LookupKind: R.getLookupKind(), S, SS: &SS, CCC,
2529	TDG: [=](const TypoCorrection &TC) {
2530	emitEmptyLookupTypoDiagnostic(TC, SemaRef&: *this, SS, Typo: Name, TypoLoc, Args,
2531	DiagnosticID: diagnostic, DiagnosticSuggestID: diagnostic_suggest);
2532	},
2533	TRC: nullptr, Mode: CTK_ErrorRecovery, MemberContext: LookupCtx);
2534	if (*Out)
2535	return true;
2536	} else if (S && (Corrected =
2537	CorrectTypo(Typo: R.getLookupNameInfo(), LookupKind: R.getLookupKind(), S,
2538	SS: &SS, CCC, Mode: CTK_ErrorRecovery, MemberContext: LookupCtx))) {
2539	std::string CorrectedStr(Corrected.getAsString(LO: getLangOpts()));
2540	bool DroppedSpecifier =
2541	Corrected.WillReplaceSpecifier() && Name.getAsString() == CorrectedStr;
2542	R.setLookupName(Corrected.getCorrection());
2543
2544	bool AcceptableWithRecovery = false;
2545	bool AcceptableWithoutRecovery = false;
2546	NamedDecl *ND = Corrected.getFoundDecl();
2547	if (ND) {
2548	if (Corrected.isOverloaded()) {
2549	OverloadCandidateSet OCS(R.getNameLoc(),
2550	OverloadCandidateSet::CSK_Normal);
2551	OverloadCandidateSet::iterator Best;
2552	for (NamedDecl *CD : Corrected) {
2553	if (FunctionTemplateDecl *FTD =
2554	dyn_cast<FunctionTemplateDecl>(Val: CD))
2555	AddTemplateOverloadCandidate(
2556	FunctionTemplate: FTD, FoundDecl: DeclAccessPair::make(FTD, AS_none), ExplicitTemplateArgs,
2557	Args, CandidateSet&: OCS);
2558	else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Val: CD))
2559	if (!ExplicitTemplateArgs || ExplicitTemplateArgs->size() == 0)
2560	AddOverloadCandidate(Function: FD, FoundDecl: DeclAccessPair::make(FD, AS_none),
2561	Args, CandidateSet&: OCS);
2562	}
2563	switch (OCS.BestViableFunction(S&: *this, Loc: R.getNameLoc(), Best)) {
2564	case OR_Success:
2565	ND = Best->FoundDecl;
2566	Corrected.setCorrectionDecl(ND);
2567	break;
2568	default:
2569	// FIXME: Arbitrarily pick the first declaration for the note.
2570	Corrected.setCorrectionDecl(ND);
2571	break;
2572	}
2573	}
2574	R.addDecl(D: ND);
2575	if (getLangOpts().CPlusPlus && ND->isCXXClassMember()) {
2576	CXXRecordDecl *Record = nullptr;
2577	if (Corrected.getCorrectionSpecifier()) {
2578	const Type *Ty = Corrected.getCorrectionSpecifier()->getAsType();
2579	Record = Ty->getAsCXXRecordDecl();
2580	}
2581	if (!Record)
2582	Record = cast<CXXRecordDecl>(
2583	ND->getDeclContext()->getRedeclContext());
2584	R.setNamingClass(Record);
2585	}
2586
2587	auto *UnderlyingND = ND->getUnderlyingDecl();
2588	AcceptableWithRecovery = isa<ValueDecl>(Val: UnderlyingND) ||
2589	isa<FunctionTemplateDecl>(Val: UnderlyingND);
2590	// FIXME: If we ended up with a typo for a type name or
2591	// Objective-C class name, we're in trouble because the parser
2592	// is in the wrong place to recover. Suggest the typo
2593	// correction, but don't make it a fix-it since we're not going
2594	// to recover well anyway.
2595	AcceptableWithoutRecovery = isa<TypeDecl>(Val: UnderlyingND) ||
2596	getAsTypeTemplateDecl(UnderlyingND) ||
2597	isa<ObjCInterfaceDecl>(Val: UnderlyingND);
2598	} else {
2599	// FIXME: We found a keyword. Suggest it, but don't provide a fix-it
2600	// because we aren't able to recover.
2601	AcceptableWithoutRecovery = true;
2602	}
2603
2604	if (AcceptableWithRecovery || AcceptableWithoutRecovery) {
2605	unsigned NoteID = Corrected.getCorrectionDeclAs<ImplicitParamDecl>()
2606	? diag::note_implicit_param_decl
2607	: diag::note_previous_decl;
2608	if (SS.isEmpty())
2609	diagnoseTypo(Correction: Corrected, TypoDiag: PDiag(DiagID: diagnostic_suggest) << Name,
2610	PrevNote: PDiag(DiagID: NoteID), ErrorRecovery: AcceptableWithRecovery);
2611	else
2612	diagnoseTypo(Corrected, PDiag(diag::err_no_member_suggest)
2613	<< Name << computeDeclContext(SS, false)
2614	<< DroppedSpecifier << SS.getRange(),
2615	PDiag(NoteID), AcceptableWithRecovery);
2616
2617	// Tell the callee whether to try to recover.
2618	return !AcceptableWithRecovery;
2619	}
2620	}
2621	R.clear();
2622
2623	// Emit a special diagnostic for failed member lookups.
2624	// FIXME: computing the declaration context might fail here (?)
2625	if (!SS.isEmpty()) {
2626	Diag(R.getNameLoc(), diag::err_no_member)
2627	<< Name << computeDeclContext(SS, false)
2628	<< SS.getRange();
2629	return true;
2630	}
2631
2632	// Give up, we can't recover.
2633	Diag(Loc: R.getNameLoc(), DiagID: diagnostic) << Name;
2634	return true;
2635	}
2636
2637	/// In Microsoft mode, if we are inside a template class whose parent class has
2638	/// dependent base classes, and we can't resolve an unqualified identifier, then
2639	/// assume the identifier is a member of a dependent base class. We can only
2640	/// recover successfully in static methods, instance methods, and other contexts
2641	/// where 'this' is available. This doesn't precisely match MSVC's
2642	/// instantiation model, but it's close enough.
2643	static Expr *
2644	recoverFromMSUnqualifiedLookup(Sema &S, ASTContext &Context,
2645	DeclarationNameInfo &NameInfo,
2646	SourceLocation TemplateKWLoc,
2647	const TemplateArgumentListInfo *TemplateArgs) {
2648	// Only try to recover from lookup into dependent bases in static methods or
2649	// contexts where 'this' is available.
2650	QualType ThisType = S.getCurrentThisType();
2651	const CXXRecordDecl *RD = nullptr;
2652	if (!ThisType.isNull())
2653	RD = ThisType->getPointeeType()->getAsCXXRecordDecl();
2654	else if (auto *MD = dyn_cast<CXXMethodDecl>(Val: S.CurContext))
2655	RD = MD->getParent();
2656	if (!RD || !RD->hasAnyDependentBases())
2657	return nullptr;
2658
2659	// Diagnose this as unqualified lookup into a dependent base class. If 'this'
2660	// is available, suggest inserting 'this->' as a fixit.
2661	SourceLocation Loc = NameInfo.getLoc();
2662	auto DB = S.Diag(Loc, diag::ext_undeclared_unqual_id_with_dependent_base);
2663	DB << NameInfo.getName() << RD;
2664
2665	if (!ThisType.isNull()) {
2666	DB << FixItHint::CreateInsertion(InsertionLoc: Loc, Code: "this->");
2667	return CXXDependentScopeMemberExpr::Create(
2668	Ctx: Context, /*This=*/Base: nullptr, BaseType: ThisType, /*IsArrow=*/true,
2669	/*Op=*/OperatorLoc: SourceLocation(), QualifierLoc: NestedNameSpecifierLoc(), TemplateKWLoc,
2670	/*FirstQualifierFoundInScope=*/nullptr, MemberNameInfo: NameInfo, TemplateArgs);
2671	}
2672
2673	// Synthesize a fake NNS that points to the derived class. This will
2674	// perform name lookup during template instantiation.
2675	CXXScopeSpec SS;
2676	auto *NNS =
2677	NestedNameSpecifier::Create(Context, nullptr, true, RD->getTypeForDecl());
2678	SS.MakeTrivial(Context, Qualifier: NNS, R: SourceRange(Loc, Loc));
2679	return DependentScopeDeclRefExpr::Create(
2680	Context, QualifierLoc: SS.getWithLocInContext(Context), TemplateKWLoc, NameInfo,
2681	TemplateArgs);
2682	}
2683
2684	ExprResult
2685	Sema::ActOnIdExpression(Scope *S, CXXScopeSpec &SS,
2686	SourceLocation TemplateKWLoc, UnqualifiedId &Id,
2687	bool HasTrailingLParen, bool IsAddressOfOperand,
2688	CorrectionCandidateCallback *CCC,
2689	bool IsInlineAsmIdentifier, Token *KeywordReplacement) {
2690	assert(!(IsAddressOfOperand && HasTrailingLParen) &&
2691	"cannot be direct & operand and have a trailing lparen");
2692	if (SS.isInvalid())
2693	return ExprError();
2694
2695	TemplateArgumentListInfo TemplateArgsBuffer;
2696
2697	// Decompose the UnqualifiedId into the following data.
2698	DeclarationNameInfo NameInfo;
2699	const TemplateArgumentListInfo *TemplateArgs;
2700	DecomposeUnqualifiedId(Id, Buffer&: TemplateArgsBuffer, NameInfo, TemplateArgs);
2701
2702	DeclarationName Name = NameInfo.getName();
2703	IdentifierInfo *II = Name.getAsIdentifierInfo();
2704	SourceLocation NameLoc = NameInfo.getLoc();
2705
2706	if (II && II->isEditorPlaceholder()) {
2707	// FIXME: When typed placeholders are supported we can create a typed
2708	// placeholder expression node.
2709	return ExprError();
2710	}
2711
2712	// C++ [temp.dep.expr]p3:
2713	// An id-expression is type-dependent if it contains:
2714	// -- an identifier that was declared with a dependent type,
2715	// (note: handled after lookup)
2716	// -- a template-id that is dependent,
2717	// (note: handled in BuildTemplateIdExpr)
2718	// -- a conversion-function-id that specifies a dependent type,
2719	// -- a nested-name-specifier that contains a class-name that
2720	// names a dependent type.
2721	// Determine whether this is a member of an unknown specialization;
2722	// we need to handle these differently.
2723	bool DependentID = false;
2724	if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName &&
2725	Name.getCXXNameType()->isDependentType()) {
2726	DependentID = true;
2727	} else if (SS.isSet()) {
2728	if (DeclContext *DC = computeDeclContext(SS, EnteringContext: false)) {
2729	if (RequireCompleteDeclContext(SS, DC))
2730	return ExprError();
2731	} else {
2732	DependentID = true;
2733	}
2734	}
2735
2736	if (DependentID)
2737	return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
2738	isAddressOfOperand: IsAddressOfOperand, TemplateArgs);
2739
2740	// Perform the required lookup.
2741	LookupResult R(*this, NameInfo,
2742	(Id.getKind() == UnqualifiedIdKind::IK_ImplicitSelfParam)
2743	? LookupObjCImplicitSelfParam
2744	: LookupOrdinaryName);
2745	if (TemplateKWLoc.isValid() || TemplateArgs) {
2746	// Lookup the template name again to correctly establish the context in
2747	// which it was found. This is really unfortunate as we already did the
2748	// lookup to determine that it was a template name in the first place. If
2749	// this becomes a performance hit, we can work harder to preserve those
2750	// results until we get here but it's likely not worth it.
2751	bool MemberOfUnknownSpecialization;
2752	AssumedTemplateKind AssumedTemplate;
2753	if (LookupTemplateName(R, S, SS, ObjectType: QualType(), /*EnteringContext=*/false,
2754	MemberOfUnknownSpecialization, RequiredTemplate: TemplateKWLoc,
2755	ATK: &AssumedTemplate))
2756	return ExprError();
2757
2758	if (MemberOfUnknownSpecialization ||
2759	(R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation))
2760	return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
2761	isAddressOfOperand: IsAddressOfOperand, TemplateArgs);
2762	} else {
2763	bool IvarLookupFollowUp = II && !SS.isSet() && getCurMethodDecl();
2764	LookupParsedName(R, S, SS: &SS, AllowBuiltinCreation: !IvarLookupFollowUp);
2765
2766	// If the result might be in a dependent base class, this is a dependent
2767	// id-expression.
2768	if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)
2769	return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
2770	isAddressOfOperand: IsAddressOfOperand, TemplateArgs);
2771
2772	// If this reference is in an Objective-C method, then we need to do
2773	// some special Objective-C lookup, too.
2774	if (IvarLookupFollowUp) {
2775	ExprResult E(LookupInObjCMethod(LookUp&: R, S, II, AllowBuiltinCreation: true));
2776	if (E.isInvalid())
2777	return ExprError();
2778
2779	if (Expr *Ex = E.getAs<Expr>())
2780	return Ex;
2781	}
2782	}
2783
2784	if (R.isAmbiguous())
2785	return ExprError();
2786
2787	// This could be an implicitly declared function reference if the language
2788	// mode allows it as a feature.
2789	if (R.empty() && HasTrailingLParen && II &&
2790	getLangOpts().implicitFunctionsAllowed()) {
2791	NamedDecl *D = ImplicitlyDefineFunction(Loc: NameLoc, II&: *II, S);
2792	if (D) R.addDecl(D);
2793	}
2794
2795	// Determine whether this name might be a candidate for
2796	// argument-dependent lookup.
2797	bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen);
2798
2799	if (R.empty() && !ADL) {
2800	if (SS.isEmpty() && getLangOpts().MSVCCompat) {
2801	if (Expr *E = recoverFromMSUnqualifiedLookup(S&: *this, Context, NameInfo,
2802	TemplateKWLoc, TemplateArgs))
2803	return E;
2804	}
2805
2806	// Don't diagnose an empty lookup for inline assembly.
2807	if (IsInlineAsmIdentifier)
2808	return ExprError();
2809
2810	// If this name wasn't predeclared and if this is not a function
2811	// call, diagnose the problem.
2812	TypoExpr *TE = nullptr;
2813	DefaultFilterCCC DefaultValidator(II, SS.isValid() ? SS.getScopeRep()
2814	: nullptr);
2815	DefaultValidator.IsAddressOfOperand = IsAddressOfOperand;
2816	assert((!CCC || CCC->IsAddressOfOperand == IsAddressOfOperand) &&
2817	"Typo correction callback misconfigured");
2818	if (CCC) {
2819	// Make sure the callback knows what the typo being diagnosed is.
2820	CCC->setTypoName(II);
2821	if (SS.isValid())
2822	CCC->setTypoNNS(SS.getScopeRep());
2823	}
2824	// FIXME: DiagnoseEmptyLookup produces bad diagnostics if we're looking for
2825	// a template name, but we happen to have always already looked up the name
2826	// before we get here if it must be a template name.
2827	if (DiagnoseEmptyLookup(S, SS, R, CCC&: CCC ? *CCC : DefaultValidator, ExplicitTemplateArgs: nullptr,
2828	Args: std::nullopt, LookupCtx: nullptr, Out: &TE)) {
2829	if (TE && KeywordReplacement) {
2830	auto &State = getTypoExprState(TE);
2831	auto BestTC = State.Consumer->getNextCorrection();
2832	if (BestTC.isKeyword()) {
2833	auto *II = BestTC.getCorrectionAsIdentifierInfo();
2834	if (State.DiagHandler)
2835	State.DiagHandler(BestTC);
2836	KeywordReplacement->startToken();
2837	KeywordReplacement->setKind(II->getTokenID());
2838	KeywordReplacement->setIdentifierInfo(II);
2839	KeywordReplacement->setLocation(BestTC.getCorrectionRange().getBegin());
2840	// Clean up the state associated with the TypoExpr, since it has
2841	// now been diagnosed (without a call to CorrectDelayedTyposInExpr).
2842	clearDelayedTypo(TE);
2843	// Signal that a correction to a keyword was performed by returning a
2844	// valid-but-null ExprResult.
2845	return (Expr*)nullptr;
2846	}
2847	State.Consumer->resetCorrectionStream();
2848	}
2849	return TE ? TE : ExprError();
2850	}
2851
2852	assert(!R.empty() &&
2853	"DiagnoseEmptyLookup returned false but added no results");
2854
2855	// If we found an Objective-C instance variable, let
2856	// LookupInObjCMethod build the appropriate expression to
2857	// reference the ivar.
2858	if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) {
2859	R.clear();
2860	ExprResult E(LookupInObjCMethod(LookUp&: R, S, II: Ivar->getIdentifier()));
2861	// In a hopelessly buggy code, Objective-C instance variable
2862	// lookup fails and no expression will be built to reference it.
2863	if (!E.isInvalid() && !E.get())
2864	return ExprError();
2865	return E;
2866	}
2867	}
2868
2869	// This is guaranteed from this point on.
2870	assert(!R.empty() || ADL);
2871
2872	// Check whether this might be a C++ implicit instance member access.
2873	// C++ [class.mfct.non-static]p3:
2874	// When an id-expression that is not part of a class member access
2875	// syntax and not used to form a pointer to member is used in the
2876	// body of a non-static member function of class X, if name lookup
2877	// resolves the name in the id-expression to a non-static non-type
2878	// member of some class C, the id-expression is transformed into a
2879	// class member access expression using (*this) as the
2880	// postfix-expression to the left of the . operator.
2881	//
2882	// But we don't actually need to do this for '&' operands if R
2883	// resolved to a function or overloaded function set, because the
2884	// expression is ill-formed if it actually works out to be a
2885	// non-static member function:
2886	//
2887	// C++ [expr.ref]p4:
2888	// Otherwise, if E1.E2 refers to a non-static member function. . .
2889	// [t]he expression can be used only as the left-hand operand of a
2890	// member function call.
2891	//
2892	// There are other safeguards against such uses, but it's important
2893	// to get this right here so that we don't end up making a
2894	// spuriously dependent expression if we're inside a dependent
2895	// instance method.
2896	if (!R.empty() && (*R.begin())->isCXXClassMember()) {
2897	bool MightBeImplicitMember;
2898	if (!IsAddressOfOperand)
2899	MightBeImplicitMember = true;
2900	else if (!SS.isEmpty())
2901	MightBeImplicitMember = false;
2902	else if (R.isOverloadedResult())
2903	MightBeImplicitMember = false;
2904	else if (R.isUnresolvableResult())
2905	MightBeImplicitMember = true;
2906	else
2907	MightBeImplicitMember = isa<FieldDecl>(Val: R.getFoundDecl()) ||
2908	isa<IndirectFieldDecl>(Val: R.getFoundDecl()) ||
2909	isa<MSPropertyDecl>(Val: R.getFoundDecl());
2910
2911	if (MightBeImplicitMember)
2912	return BuildPossibleImplicitMemberExpr(SS, TemplateKWLoc,
2913	R, TemplateArgs, S);
2914	}
2915
2916	if (TemplateArgs || TemplateKWLoc.isValid()) {
2917
2918	// In C++1y, if this is a variable template id, then check it
2919	// in BuildTemplateIdExpr().
2920	// The single lookup result must be a variable template declaration.
2921	if (Id.getKind() == UnqualifiedIdKind::IK_TemplateId && Id.TemplateId &&
2922	Id.TemplateId->Kind == TNK_Var_template) {
2923	assert(R.getAsSingle<VarTemplateDecl>() &&
2924	"There should only be one declaration found.");
2925	}
2926
2927	return BuildTemplateIdExpr(SS, TemplateKWLoc, R, RequiresADL: ADL, TemplateArgs);
2928	}
2929
2930	return BuildDeclarationNameExpr(SS, R, NeedsADL: ADL);
2931	}
2932
2933	/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified
2934	/// declaration name, generally during template instantiation.
2935	/// There's a large number of things which don't need to be done along
2936	/// this path.
2937	ExprResult Sema::BuildQualifiedDeclarationNameExpr(
2938	CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo,
2939	bool IsAddressOfOperand, const Scope *S, TypeSourceInfo **RecoveryTSI) {
2940	if (NameInfo.getName().isDependentName())
2941	return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(),
2942	NameInfo, /*TemplateArgs=*/nullptr);
2943
2944	DeclContext *DC = computeDeclContext(SS, EnteringContext: false);
2945	if (!DC)
2946	return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(),
2947	NameInfo, /*TemplateArgs=*/nullptr);
2948
2949	if (RequireCompleteDeclContext(SS, DC))
2950	return ExprError();
2951
2952	LookupResult R(*this, NameInfo, LookupOrdinaryName);
2953	LookupQualifiedName(R, LookupCtx: DC);
2954
2955	if (R.isAmbiguous())
2956	return ExprError();
2957
2958	if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)
2959	return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(),
2960	NameInfo, /*TemplateArgs=*/nullptr);
2961
2962	if (R.empty()) {
2963	// Don't diagnose problems with invalid record decl, the secondary no_member
2964	// diagnostic during template instantiation is likely bogus, e.g. if a class
2965	// is invalid because it's derived from an invalid base class, then missing
2966	// members were likely supposed to be inherited.
2967	if (const auto *CD = dyn_cast<CXXRecordDecl>(Val: DC))
2968	if (CD->isInvalidDecl())
2969	return ExprError();
2970	Diag(NameInfo.getLoc(), diag::err_no_member)
2971	<< NameInfo.getName() << DC << SS.getRange();
2972	return ExprError();
2973	}
2974
2975	if (const TypeDecl *TD = R.getAsSingle<TypeDecl>()) {
2976	// Diagnose a missing typename if this resolved unambiguously to a type in
2977	// a dependent context. If we can recover with a type, downgrade this to
2978	// a warning in Microsoft compatibility mode.
2979	unsigned DiagID = diag::err_typename_missing;
2980	if (RecoveryTSI && getLangOpts().MSVCCompat)
2981	DiagID = diag::ext_typename_missing;
2982	SourceLocation Loc = SS.getBeginLoc();
2983	auto D = Diag(Loc, DiagID);
2984	D << SS.getScopeRep() << NameInfo.getName().getAsString()
2985	<< SourceRange(Loc, NameInfo.getEndLoc());
2986
2987	// Don't recover if the caller isn't expecting us to or if we're in a SFINAE
2988	// context.
2989	if (!RecoveryTSI)
2990	return ExprError();
2991
2992	// Only issue the fixit if we're prepared to recover.
2993	D << FixItHint::CreateInsertion(InsertionLoc: Loc, Code: "typename ");
2994
2995	// Recover by pretending this was an elaborated type.
2996	QualType Ty = Context.getTypeDeclType(Decl: TD);
2997	TypeLocBuilder TLB;
2998	TLB.pushTypeSpec(T: Ty).setNameLoc(NameInfo.getLoc());
2999
3000	QualType ET = getElaboratedType(Keyword: ElaboratedTypeKeyword::None, SS, T: Ty);
3001	ElaboratedTypeLoc QTL = TLB.push<ElaboratedTypeLoc>(T: ET);
3002	QTL.setElaboratedKeywordLoc(SourceLocation());
3003	QTL.setQualifierLoc(SS.getWithLocInContext(Context));
3004
3005	*RecoveryTSI = TLB.getTypeSourceInfo(Context, T: ET);
3006
3007	return ExprEmpty();
3008	}
3009
3010	// Defend against this resolving to an implicit member access. We usually
3011	// won't get here if this might be a legitimate a class member (we end up in
3012	// BuildMemberReferenceExpr instead), but this can be valid if we're forming
3013	// a pointer-to-member or in an unevaluated context in C++11.
3014	if (!R.empty() && (*R.begin())->isCXXClassMember() && !IsAddressOfOperand)
3015	return BuildPossibleImplicitMemberExpr(SS,
3016	/*TemplateKWLoc=*/SourceLocation(),
3017	R, /*TemplateArgs=*/nullptr, S);
3018
3019	return BuildDeclarationNameExpr(SS, R, /* ADL */ NeedsADL: false);
3020	}
3021
3022	/// The parser has read a name in, and Sema has detected that we're currently
3023	/// inside an ObjC method. Perform some additional checks and determine if we
3024	/// should form a reference to an ivar.
3025	///
3026	/// Ideally, most of this would be done by lookup, but there's
3027	/// actually quite a lot of extra work involved.
3028	DeclResult Sema::LookupIvarInObjCMethod(LookupResult &Lookup, Scope *S,
3029	IdentifierInfo *II) {
3030	SourceLocation Loc = Lookup.getNameLoc();
3031	ObjCMethodDecl *CurMethod = getCurMethodDecl();
3032
3033	// Check for error condition which is already reported.
3034	if (!CurMethod)
3035	return DeclResult(true);
3036
3037	// There are two cases to handle here. 1) scoped lookup could have failed,
3038	// in which case we should look for an ivar. 2) scoped lookup could have
3039	// found a decl, but that decl is outside the current instance method (i.e.
3040	// a global variable). In these two cases, we do a lookup for an ivar with
3041	// this name, if the lookup sucedes, we replace it our current decl.
3042
3043	// If we're in a class method, we don't normally want to look for
3044	// ivars. But if we don't find anything else, and there's an
3045	// ivar, that's an error.
3046	bool IsClassMethod = CurMethod->isClassMethod();
3047
3048	bool LookForIvars;
3049	if (Lookup.empty())
3050	LookForIvars = true;
3051	else if (IsClassMethod)
3052	LookForIvars = false;
3053	else
3054	LookForIvars = (Lookup.isSingleResult() &&
3055	Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod());
3056	ObjCInterfaceDecl *IFace = nullptr;
3057	if (LookForIvars) {
3058	IFace = CurMethod->getClassInterface();
3059	ObjCInterfaceDecl *ClassDeclared;
3060	ObjCIvarDecl *IV = nullptr;
3061	if (IFace && (IV = IFace->lookupInstanceVariable(IVarName: II, ClassDeclared))) {
3062	// Diagnose using an ivar in a class method.
3063	if (IsClassMethod) {
3064	Diag(Loc, diag::err_ivar_use_in_class_method) << IV->getDeclName();
3065	return DeclResult(true);
3066	}
3067
3068	// Diagnose the use of an ivar outside of the declaring class.
3069	if (IV->getAccessControl() == ObjCIvarDecl::Private &&
3070	!declaresSameEntity(ClassDeclared, IFace) &&
3071	!getLangOpts().DebuggerSupport)
3072	Diag(Loc, diag::err_private_ivar_access) << IV->getDeclName();
3073
3074	// Success.
3075	return IV;
3076	}
3077	} else if (CurMethod->isInstanceMethod()) {
3078	// We should warn if a local variable hides an ivar.
3079	if (ObjCInterfaceDecl *IFace = CurMethod->getClassInterface()) {
3080	ObjCInterfaceDecl *ClassDeclared;
3081	if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(IVarName: II, ClassDeclared)) {
3082	if (IV->getAccessControl() != ObjCIvarDecl::Private ||
3083	declaresSameEntity(IFace, ClassDeclared))
3084	Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName();
3085	}
3086	}
3087	} else if (Lookup.isSingleResult() &&
3088	Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()) {
3089	// If accessing a stand-alone ivar in a class method, this is an error.
3090	if (const ObjCIvarDecl *IV =
3091	dyn_cast<ObjCIvarDecl>(Val: Lookup.getFoundDecl())) {
3092	Diag(Loc, diag::err_ivar_use_in_class_method) << IV->getDeclName();
3093	return DeclResult(true);
3094	}
3095	}
3096
3097	// Didn't encounter an error, didn't find an ivar.
3098	return DeclResult(false);
3099	}
3100
3101	ExprResult Sema::BuildIvarRefExpr(Scope *S, SourceLocation Loc,
3102	ObjCIvarDecl *IV) {
3103	ObjCMethodDecl *CurMethod = getCurMethodDecl();
3104	assert(CurMethod && CurMethod->isInstanceMethod() &&
3105	"should not reference ivar from this context");
3106
3107	ObjCInterfaceDecl *IFace = CurMethod->getClassInterface();
3108	assert(IFace && "should not reference ivar from this context");
3109
3110	// If we're referencing an invalid decl, just return this as a silent
3111	// error node. The error diagnostic was already emitted on the decl.
3112	if (IV->isInvalidDecl())
3113	return ExprError();
3114
3115	// Check if referencing a field with __attribute__((deprecated)).
3116	if (DiagnoseUseOfDecl(IV, Loc))
3117	return ExprError();
3118
3119	// FIXME: This should use a new expr for a direct reference, don't
3120	// turn this into Self->ivar, just return a BareIVarExpr or something.
3121	IdentifierInfo &II = Context.Idents.get(Name: "self");
3122	UnqualifiedId SelfName;
3123	SelfName.setImplicitSelfParam(&II);
3124	CXXScopeSpec SelfScopeSpec;
3125	SourceLocation TemplateKWLoc;
3126	ExprResult SelfExpr =
3127	ActOnIdExpression(S, SS&: SelfScopeSpec, TemplateKWLoc, Id&: SelfName,
3128	/*HasTrailingLParen=*/false,
3129	/*IsAddressOfOperand=*/false);
3130	if (SelfExpr.isInvalid())
3131	return ExprError();
3132
3133	SelfExpr = DefaultLvalueConversion(E: SelfExpr.get());
3134	if (SelfExpr.isInvalid())
3135	return ExprError();
3136
3137	MarkAnyDeclReferenced(Loc, IV, true);
3138
3139	ObjCMethodFamily MF = CurMethod->getMethodFamily();
3140	if (MF != OMF_init && MF != OMF_dealloc && MF != OMF_finalize &&
3141	!IvarBacksCurrentMethodAccessor(IFace, CurMethod, IV))
3142	Diag(Loc, diag::warn_direct_ivar_access) << IV->getDeclName();
3143
3144	ObjCIvarRefExpr *Result = new (Context)
3145	ObjCIvarRefExpr(IV, IV->getUsageType(objectType: SelfExpr.get()->getType()), Loc,
3146	IV->getLocation(), SelfExpr.get(), true, true);
3147
3148	if (IV->getType().getObjCLifetime() == Qualifiers::OCL_Weak) {
3149	if (!isUnevaluatedContext() &&
3150	!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, Loc))
3151	getCurFunction()->recordUseOfWeak(E: Result);
3152	}
3153	if (getLangOpts().ObjCAutoRefCount && !isUnevaluatedContext())
3154	if (const BlockDecl *BD = CurContext->getInnermostBlockDecl())
3155	ImplicitlyRetainedSelfLocs.push_back(Elt: {Loc, BD});
3156
3157	return Result;
3158	}
3159
3160	/// The parser has read a name in, and Sema has detected that we're currently
3161	/// inside an ObjC method. Perform some additional checks and determine if we
3162	/// should form a reference to an ivar. If so, build an expression referencing
3163	/// that ivar.
3164	ExprResult
3165	Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S,
3166	IdentifierInfo *II, bool AllowBuiltinCreation) {
3167	// FIXME: Integrate this lookup step into LookupParsedName.
3168	DeclResult Ivar = LookupIvarInObjCMethod(Lookup, S, II);
3169	if (Ivar.isInvalid())
3170	return ExprError();
3171	if (Ivar.isUsable())
3172	return BuildIvarRefExpr(S, Loc: Lookup.getNameLoc(),
3173	IV: cast<ObjCIvarDecl>(Val: Ivar.get()));
3174
3175	if (Lookup.empty() && II && AllowBuiltinCreation)
3176	LookupBuiltin(R&: Lookup);
3177
3178	// Sentinel value saying that we didn't do anything special.
3179	return ExprResult(false);
3180	}
3181
3182	/// Cast a base object to a member's actual type.
3183	///
3184	/// There are two relevant checks:
3185	///
3186	/// C++ [class.access.base]p7:
3187	///
3188	/// If a class member access operator [...] is used to access a non-static
3189	/// data member or non-static member function, the reference is ill-formed if
3190	/// the left operand [...] cannot be implicitly converted to a pointer to the
3191	/// naming class of the right operand.
3192	///
3193	/// C++ [expr.ref]p7:
3194	///
3195	/// If E2 is a non-static data member or a non-static member function, the
3196	/// program is ill-formed if the class of which E2 is directly a member is an
3197	/// ambiguous base (11.8) of the naming class (11.9.3) of E2.
3198	///
3199	/// Note that the latter check does not consider access; the access of the
3200	/// "real" base class is checked as appropriate when checking the access of the
3201	/// member name.
3202	ExprResult
3203	Sema::PerformObjectMemberConversion(Expr *From,
3204	NestedNameSpecifier *Qualifier,
3205	NamedDecl *FoundDecl,
3206	NamedDecl *Member) {
3207	const auto *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext());
3208	if (!RD)
3209	return From;
3210
3211	QualType DestRecordType;
3212	QualType DestType;
3213	QualType FromRecordType;
3214	QualType FromType = From->getType();
3215	bool PointerConversions = false;
3216	if (isa<FieldDecl>(Val: Member)) {
3217	DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(Decl: RD));
3218	auto FromPtrType = FromType->getAs<PointerType>();
3219	DestRecordType = Context.getAddrSpaceQualType(
3220	T: DestRecordType, AddressSpace: FromPtrType
3221	? FromType->getPointeeType().getAddressSpace()
3222	: FromType.getAddressSpace());
3223
3224	if (FromPtrType) {
3225	DestType = Context.getPointerType(T: DestRecordType);
3226	FromRecordType = FromPtrType->getPointeeType();
3227	PointerConversions = true;
3228	} else {
3229	DestType = DestRecordType;
3230	FromRecordType = FromType;
3231	}
3232	} else if (const auto *Method = dyn_cast<CXXMethodDecl>(Val: Member)) {
3233	if (!Method->isImplicitObjectMemberFunction())
3234	return From;
3235
3236	DestType = Method->getThisType().getNonReferenceType();
3237	DestRecordType = Method->getFunctionObjectParameterType();
3238
3239	if (FromType->getAs<PointerType>()) {
3240	FromRecordType = FromType->getPointeeType();
3241	PointerConversions = true;
3242	} else {
3243	FromRecordType = FromType;
3244	DestType = DestRecordType;
3245	}
3246
3247	LangAS FromAS = FromRecordType.getAddressSpace();
3248	LangAS DestAS = DestRecordType.getAddressSpace();
3249	if (FromAS != DestAS) {
3250	QualType FromRecordTypeWithoutAS =
3251	Context.removeAddrSpaceQualType(T: FromRecordType);
3252	QualType FromTypeWithDestAS =
3253	Context.getAddrSpaceQualType(T: FromRecordTypeWithoutAS, AddressSpace: DestAS);
3254	if (PointerConversions)
3255	FromTypeWithDestAS = Context.getPointerType(T: FromTypeWithDestAS);
3256	From = ImpCastExprToType(E: From, Type: FromTypeWithDestAS,
3257	CK: CK_AddressSpaceConversion, VK: From->getValueKind())
3258	.get();
3259	}
3260	} else {
3261	// No conversion necessary.
3262	return From;
3263	}
3264
3265	if (DestType->isDependentType() || FromType->isDependentType())
3266	return From;
3267
3268	// If the unqualified types are the same, no conversion is necessary.
3269	if (Context.hasSameUnqualifiedType(T1: FromRecordType, T2: DestRecordType))
3270	return From;
3271
3272	SourceRange FromRange = From->getSourceRange();
3273	SourceLocation FromLoc = FromRange.getBegin();
3274
3275	ExprValueKind VK = From->getValueKind();
3276
3277	// C++ [class.member.lookup]p8:
3278	// [...] Ambiguities can often be resolved by qualifying a name with its
3279	// class name.
3280	//
3281	// If the member was a qualified name and the qualified referred to a
3282	// specific base subobject type, we'll cast to that intermediate type
3283	// first and then to the object in which the member is declared. That allows
3284	// one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as:
3285	//
3286	// class Base { public: int x; };
3287	// class Derived1 : public Base { };
3288	// class Derived2 : public Base { };
3289	// class VeryDerived : public Derived1, public Derived2 { void f(); };
3290	//
3291	// void VeryDerived::f() {
3292	// x = 17; // error: ambiguous base subobjects
3293	// Derived1::x = 17; // okay, pick the Base subobject of Derived1
3294	// }
3295	if (Qualifier && Qualifier->getAsType()) {
3296	QualType QType = QualType(Qualifier->getAsType(), 0);
3297	assert(QType->isRecordType() && "lookup done with non-record type");
3298
3299	QualType QRecordType = QualType(QType->castAs<RecordType>(), 0);
3300
3301	// In C++98, the qualifier type doesn't actually have to be a base
3302	// type of the object type, in which case we just ignore it.
3303	// Otherwise build the appropriate casts.
3304	if (IsDerivedFrom(Loc: FromLoc, Derived: FromRecordType, Base: QRecordType)) {
3305	CXXCastPath BasePath;
3306	if (CheckDerivedToBaseConversion(Derived: FromRecordType, Base: QRecordType,
3307	Loc: FromLoc, Range: FromRange, BasePath: &BasePath))
3308	return ExprError();
3309
3310	if (PointerConversions)
3311	QType = Context.getPointerType(T: QType);
3312	From = ImpCastExprToType(E: From, Type: QType, CK: CK_UncheckedDerivedToBase,
3313	VK, BasePath: &BasePath).get();
3314
3315	FromType = QType;
3316	FromRecordType = QRecordType;
3317
3318	// If the qualifier type was the same as the destination type,
3319	// we're done.
3320	if (Context.hasSameUnqualifiedType(T1: FromRecordType, T2: DestRecordType))
3321	return From;
3322	}
3323	}
3324
3325	CXXCastPath BasePath;
3326	if (CheckDerivedToBaseConversion(Derived: FromRecordType, Base: DestRecordType,
3327	Loc: FromLoc, Range: FromRange, BasePath: &BasePath,
3328	/*IgnoreAccess=*/true))
3329	return ExprError();
3330
3331	return ImpCastExprToType(E: From, Type: DestType, CK: CK_UncheckedDerivedToBase,
3332	VK, BasePath: &BasePath);
3333	}
3334
3335	bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS,
3336	const LookupResult &R,
3337	bool HasTrailingLParen) {
3338	// Only when used directly as the postfix-expression of a call.
3339	if (!HasTrailingLParen)
3340	return false;
3341
3342	// Never if a scope specifier was provided.
3343	if (SS.isSet())
3344	return false;
3345
3346	// Only in C++ or ObjC++.
3347	if (!getLangOpts().CPlusPlus)
3348	return false;
3349
3350	// Turn off ADL when we find certain kinds of declarations during
3351	// normal lookup:
3352	for (const NamedDecl *D : R) {
3353	// C++0x [basic.lookup.argdep]p3:
3354	// -- a declaration of a class member
3355	// Since using decls preserve this property, we check this on the
3356	// original decl.
3357	if (D->isCXXClassMember())
3358	return false;
3359
3360	// C++0x [basic.lookup.argdep]p3:
3361	// -- a block-scope function declaration that is not a
3362	// using-declaration
3363	// NOTE: we also trigger this for function templates (in fact, we
3364	// don't check the decl type at all, since all other decl types
3365	// turn off ADL anyway).
3366	if (isa<UsingShadowDecl>(Val: D))
3367	D = cast<UsingShadowDecl>(Val: D)->getTargetDecl();
3368	else if (D->getLexicalDeclContext()->isFunctionOrMethod())
3369	return false;
3370
3371	// C++0x [basic.lookup.argdep]p3:
3372	// -- a declaration that is neither a function or a function
3373	// template
3374	// And also for builtin functions.
3375	if (const auto *FDecl = dyn_cast<FunctionDecl>(Val: D)) {
3376	// But also builtin functions.
3377	if (FDecl->getBuiltinID() && FDecl->isImplicit())
3378	return false;
3379	} else if (!isa<FunctionTemplateDecl>(Val: D))
3380	return false;
3381	}
3382
3383	return true;
3384	}
3385
3386
3387	/// Diagnoses obvious problems with the use of the given declaration
3388	/// as an expression. This is only actually called for lookups that
3389	/// were not overloaded, and it doesn't promise that the declaration
3390	/// will in fact be used.
3391	static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D,
3392	bool AcceptInvalid) {
3393	if (D->isInvalidDecl() && !AcceptInvalid)
3394	return true;
3395
3396	if (isa<TypedefNameDecl>(Val: D)) {
3397	S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName();
3398	return true;
3399	}
3400
3401	if (isa<ObjCInterfaceDecl>(Val: D)) {
3402	S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName();
3403	return true;
3404	}
3405
3406	if (isa<NamespaceDecl>(Val: D)) {
3407	S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName();
3408	return true;
3409	}
3410
3411	return false;
3412	}
3413
3414	// Certain multiversion types should be treated as overloaded even when there is
3415	// only one result.
3416	static bool ShouldLookupResultBeMultiVersionOverload(const LookupResult &R) {
3417	assert(R.isSingleResult() && "Expected only a single result");
3418	const auto *FD = dyn_cast<FunctionDecl>(Val: R.getFoundDecl());
3419	return FD &&
3420	(FD->isCPUDispatchMultiVersion() || FD->isCPUSpecificMultiVersion());
3421	}
3422
3423	ExprResult Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS,
3424	LookupResult &R, bool NeedsADL,
3425	bool AcceptInvalidDecl) {
3426	// If this is a single, fully-resolved result and we don't need ADL,
3427	// just build an ordinary singleton decl ref.
3428	if (!NeedsADL && R.isSingleResult() &&
3429	!R.getAsSingle<FunctionTemplateDecl>() &&
3430	!ShouldLookupResultBeMultiVersionOverload(R))
3431	return BuildDeclarationNameExpr(SS, NameInfo: R.getLookupNameInfo(), D: R.getFoundDecl(),
3432	FoundD: R.getRepresentativeDecl(), TemplateArgs: nullptr,
3433	AcceptInvalidDecl);
3434
3435	// We only need to check the declaration if there's exactly one
3436	// result, because in the overloaded case the results can only be
3437	// functions and function templates.
3438	if (R.isSingleResult() && !ShouldLookupResultBeMultiVersionOverload(R) &&
3439	CheckDeclInExpr(S&: *this, Loc: R.getNameLoc(), D: R.getFoundDecl(),
3440	AcceptInvalid: AcceptInvalidDecl))
3441	return ExprError();
3442
3443	// Otherwise, just build an unresolved lookup expression. Suppress
3444	// any lookup-related diagnostics; we'll hash these out later, when
3445	// we've picked a target.
3446	R.suppressDiagnostics();
3447
3448	UnresolvedLookupExpr *ULE
3449	= UnresolvedLookupExpr::Create(Context, NamingClass: R.getNamingClass(),
3450	QualifierLoc: SS.getWithLocInContext(Context),
3451	NameInfo: R.getLookupNameInfo(),
3452	RequiresADL: NeedsADL, Overloaded: R.isOverloadedResult(),
3453	Begin: R.begin(), End: R.end());
3454
3455	return ULE;
3456	}
3457
3458	static void diagnoseUncapturableValueReferenceOrBinding(Sema &S,
3459	SourceLocation loc,
3460	ValueDecl *var);
3461
3462	/// Complete semantic analysis for a reference to the given declaration.
3463	ExprResult Sema::BuildDeclarationNameExpr(
3464	const CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo, NamedDecl *D,
3465	NamedDecl *FoundD, const TemplateArgumentListInfo *TemplateArgs,
3466	bool AcceptInvalidDecl) {
3467	assert(D && "Cannot refer to a NULL declaration");
3468	assert(!isa<FunctionTemplateDecl>(D) &&
3469	"Cannot refer unambiguously to a function template");
3470
3471	SourceLocation Loc = NameInfo.getLoc();
3472	if (CheckDeclInExpr(S&: *this, Loc, D, AcceptInvalid: AcceptInvalidDecl)) {
3473	// Recovery from invalid cases (e.g. D is an invalid Decl).
3474	// We use the dependent type for the RecoveryExpr to prevent bogus follow-up
3475	// diagnostics, as invalid decls use int as a fallback type.
3476	return CreateRecoveryExpr(Begin: NameInfo.getBeginLoc(), End: NameInfo.getEndLoc(), SubExprs: {});
3477	}
3478
3479	if (TemplateDecl *Template = dyn_cast<TemplateDecl>(Val: D)) {
3480	// Specifically diagnose references to class templates that are missing
3481	// a template argument list.
3482	diagnoseMissingTemplateArguments(Name: TemplateName(Template), Loc);
3483	return ExprError();
3484	}
3485
3486	// Make sure that we're referring to a value.
3487	if (!isa<ValueDecl, UnresolvedUsingIfExistsDecl>(Val: D)) {
3488	Diag(Loc, diag::err_ref_non_value) << D << SS.getRange();
3489	Diag(D->getLocation(), diag::note_declared_at);
3490	return ExprError();
3491	}
3492
3493	// Check whether this declaration can be used. Note that we suppress
3494	// this check when we're going to perform argument-dependent lookup
3495	// on this function name, because this might not be the function
3496	// that overload resolution actually selects.
3497	if (DiagnoseUseOfDecl(D, Locs: Loc))
3498	return ExprError();
3499
3500	auto *VD = cast<ValueDecl>(Val: D);
3501
3502	// Only create DeclRefExpr's for valid Decl's.
3503	if (VD->isInvalidDecl() && !AcceptInvalidDecl)
3504	return ExprError();
3505
3506	// Handle members of anonymous structs and unions. If we got here,
3507	// and the reference is to a class member indirect field, then this
3508	// must be the subject of a pointer-to-member expression.
3509	if (auto *IndirectField = dyn_cast<IndirectFieldDecl>(Val: VD);
3510	IndirectField && !IndirectField->isCXXClassMember())
3511	return BuildAnonymousStructUnionMemberReference(SS, nameLoc: NameInfo.getLoc(),
3512	indirectField: IndirectField);
3513
3514	QualType type = VD->getType();
3515	if (type.isNull())
3516	return ExprError();
3517	ExprValueKind valueKind = VK_PRValue;
3518
3519	// In 'T ...V;', the type of the declaration 'V' is 'T...', but the type of
3520	// a reference to 'V' is simply (unexpanded) 'T'. The type, like the value,
3521	// is expanded by some outer '...' in the context of the use.
3522	type = type.getNonPackExpansionType();
3523
3524	switch (D->getKind()) {
3525	// Ignore all the non-ValueDecl kinds.
3526	#define ABSTRACT_DECL(kind)
3527	#define VALUE(type, base)
3528	#define DECL(type, base) case Decl::type:
3529	#include "clang/AST/DeclNodes.inc"
3530	llvm_unreachable("invalid value decl kind");
3531
3532	// These shouldn't make it here.
3533	case Decl::ObjCAtDefsField:
3534	llvm_unreachable("forming non-member reference to ivar?");
3535
3536	// Enum constants are always r-values and never references.
3537	// Unresolved using declarations are dependent.
3538	case Decl::EnumConstant:
3539	case Decl::UnresolvedUsingValue:
3540	case Decl::OMPDeclareReduction:
3541	case Decl::OMPDeclareMapper:
3542	valueKind = VK_PRValue;
3543	break;
3544
3545	// Fields and indirect fields that got here must be for
3546	// pointer-to-member expressions; we just call them l-values for
3547	// internal consistency, because this subexpression doesn't really
3548	// exist in the high-level semantics.
3549	case Decl::Field:
3550	case Decl::IndirectField:
3551	case Decl::ObjCIvar:
3552	assert(getLangOpts().CPlusPlus && "building reference to field in C?");
3553
3554	// These can't have reference type in well-formed programs, but
3555	// for internal consistency we do this anyway.
3556	type = type.getNonReferenceType();
3557	valueKind = VK_LValue;
3558	break;
3559
3560	// Non-type template parameters are either l-values or r-values
3561	// depending on the type.
3562	case Decl::NonTypeTemplateParm: {
3563	if (const ReferenceType *reftype = type->getAs<ReferenceType>()) {
3564	type = reftype->getPointeeType();
3565	valueKind = VK_LValue; // even if the parameter is an r-value reference
3566	break;
3567	}
3568
3569	// [expr.prim.id.unqual]p2:
3570	// If the entity is a template parameter object for a template
3571	// parameter of type T, the type of the expression is const T.
3572	// [...] The expression is an lvalue if the entity is a [...] template
3573	// parameter object.
3574	if (type->isRecordType()) {
3575	type = type.getUnqualifiedType().withConst();
3576	valueKind = VK_LValue;
3577	break;
3578	}
3579
3580	// For non-references, we need to strip qualifiers just in case
3581	// the template parameter was declared as 'const int' or whatever.
3582	valueKind = VK_PRValue;
3583	type = type.getUnqualifiedType();
3584	break;
3585	}
3586
3587	case Decl::Var:
3588	case Decl::VarTemplateSpecialization:
3589	case Decl::VarTemplatePartialSpecialization:
3590	case Decl::Decomposition:
3591	case Decl::OMPCapturedExpr:
3592	// In C, "extern void blah;" is valid and is an r-value.
3593	if (!getLangOpts().CPlusPlus && !type.hasQualifiers() &&
3594	type->isVoidType()) {
3595	valueKind = VK_PRValue;
3596	break;
3597	}
3598	[[fallthrough]];
3599
3600	case Decl::ImplicitParam:
3601	case Decl::ParmVar: {
3602	// These are always l-values.
3603	valueKind = VK_LValue;
3604	type = type.getNonReferenceType();
3605
3606	// FIXME: Does the addition of const really only apply in
3607	// potentially-evaluated contexts? Since the variable isn't actually
3608	// captured in an unevaluated context, it seems that the answer is no.
3609	if (!isUnevaluatedContext()) {
3610	QualType CapturedType = getCapturedDeclRefType(Var: cast<VarDecl>(VD), Loc);
3611	if (!CapturedType.isNull())
3612	type = CapturedType;
3613	}
3614
3615	break;
3616	}
3617
3618	case Decl::Binding:
3619	// These are always lvalues.
3620	valueKind = VK_LValue;
3621	type = type.getNonReferenceType();
3622	break;
3623
3624	case Decl::Function: {
3625	if (unsigned BID = cast<FunctionDecl>(VD)->getBuiltinID()) {
3626	if (!Context.BuiltinInfo.isDirectlyAddressable(ID: BID)) {
3627	type = Context.BuiltinFnTy;
3628	valueKind = VK_PRValue;
3629	break;
3630	}
3631	}
3632
3633	const FunctionType *fty = type->castAs<FunctionType>();
3634
3635	// If we're referring to a function with an __unknown_anytype
3636	// result type, make the entire expression __unknown_anytype.
3637	if (fty->getReturnType() == Context.UnknownAnyTy) {
3638	type = Context.UnknownAnyTy;
3639	valueKind = VK_PRValue;
3640	break;
3641	}
3642
3643	// Functions are l-values in C++.
3644	if (getLangOpts().CPlusPlus) {
3645	valueKind = VK_LValue;
3646	break;
3647	}
3648
3649	// C99 DR 316 says that, if a function type comes from a
3650	// function definition (without a prototype), that type is only
3651	// used for checking compatibility. Therefore, when referencing
3652	// the function, we pretend that we don't have the full function
3653	// type.
3654	if (!cast<FunctionDecl>(VD)->hasPrototype() && isa<FunctionProtoType>(fty))
3655	type = Context.getFunctionNoProtoType(ResultTy: fty->getReturnType(),
3656	Info: fty->getExtInfo());
3657
3658	// Functions are r-values in C.
3659	valueKind = VK_PRValue;
3660	break;
3661	}
3662
3663	case Decl::CXXDeductionGuide:
3664	llvm_unreachable("building reference to deduction guide");
3665
3666	case Decl::MSProperty:
3667	case Decl::MSGuid:
3668	case Decl::TemplateParamObject:
3669	// FIXME: Should MSGuidDecl and template parameter objects be subject to
3670	// capture in OpenMP, or duplicated between host and device?
3671	valueKind = VK_LValue;
3672	break;
3673
3674	case Decl::UnnamedGlobalConstant:
3675	valueKind = VK_LValue;
3676	break;
3677
3678	case Decl::CXXMethod:
3679	// If we're referring to a method with an __unknown_anytype
3680	// result type, make the entire expression __unknown_anytype.
3681	// This should only be possible with a type written directly.
3682	if (const FunctionProtoType *proto =
3683	dyn_cast<FunctionProtoType>(VD->getType()))
3684	if (proto->getReturnType() == Context.UnknownAnyTy) {
3685	type = Context.UnknownAnyTy;
3686	valueKind = VK_PRValue;
3687	break;
3688	}
3689
3690	// C++ methods are l-values if static, r-values if non-static.
3691	if (cast<CXXMethodDecl>(VD)->isStatic()) {
3692	valueKind = VK_LValue;
3693	break;
3694	}
3695	[[fallthrough]];
3696
3697	case Decl::CXXConversion:
3698	case Decl::CXXDestructor:
3699	case Decl::CXXConstructor:
3700	valueKind = VK_PRValue;
3701	break;
3702	}
3703
3704	auto *E =
3705	BuildDeclRefExpr(D: VD, Ty: type, VK: valueKind, NameInfo, SS: &SS, FoundD,
3706	/*FIXME: TemplateKWLoc*/ TemplateKWLoc: SourceLocation(), TemplateArgs);
3707	// Clang AST consumers assume a DeclRefExpr refers to a valid decl. We
3708	// wrap a DeclRefExpr referring to an invalid decl with a dependent-type
3709	// RecoveryExpr to avoid follow-up semantic analysis (thus prevent bogus
3710	// diagnostics).
3711	if (VD->isInvalidDecl() && E)
3712	return CreateRecoveryExpr(E->getBeginLoc(), E->getEndLoc(), {E});
3713	return E;
3714	}
3715
3716	static void ConvertUTF8ToWideString(unsigned CharByteWidth, StringRef Source,
3717	SmallString<32> &Target) {
3718	Target.resize(N: CharByteWidth * (Source.size() + 1));
3719	char *ResultPtr = &Target[0];
3720	const llvm::UTF8 *ErrorPtr;
3721	bool success =
3722	llvm::ConvertUTF8toWide(WideCharWidth: CharByteWidth, Source, ResultPtr, ErrorPtr);
3723	(void)success;
3724	assert(success);
3725	Target.resize(N: ResultPtr - &Target[0]);
3726	}
3727
3728	ExprResult Sema::BuildPredefinedExpr(SourceLocation Loc,
3729	PredefinedIdentKind IK) {
3730	Decl *currentDecl = getPredefinedExprDecl(DC: CurContext);
3731	if (!currentDecl) {
3732	Diag(Loc, diag::ext_predef_outside_function);
3733	currentDecl = Context.getTranslationUnitDecl();
3734	}
3735
3736	QualType ResTy;
3737	StringLiteral *SL = nullptr;
3738	if (cast<DeclContext>(Val: currentDecl)->isDependentContext())
3739	ResTy = Context.DependentTy;
3740	else {
3741	// Pre-defined identifiers are of type char[x], where x is the length of
3742	// the string.
3743	auto Str = PredefinedExpr::ComputeName(IK, CurrentDecl: currentDecl);
3744	unsigned Length = Str.length();
3745
3746	llvm::APInt LengthI(32, Length + 1);
3747	if (IK == PredefinedIdentKind::LFunction ||
3748	IK == PredefinedIdentKind::LFuncSig) {
3749	ResTy =
3750	Context.adjustStringLiteralBaseType(StrLTy: Context.WideCharTy.withConst());
3751	SmallString<32> RawChars;
3752	ConvertUTF8ToWideString(CharByteWidth: Context.getTypeSizeInChars(T: ResTy).getQuantity(),
3753	Source: Str, Target&: RawChars);
3754	ResTy = Context.getConstantArrayType(EltTy: ResTy, ArySize: LengthI, SizeExpr: nullptr,
3755	ASM: ArraySizeModifier::Normal,
3756	/*IndexTypeQuals*/ 0);
3757	SL = StringLiteral::Create(Ctx: Context, Str: RawChars, Kind: StringLiteralKind::Wide,
3758	/*Pascal*/ false, Ty: ResTy, Loc);
3759	} else {
3760	ResTy = Context.adjustStringLiteralBaseType(StrLTy: Context.CharTy.withConst());
3761	ResTy = Context.getConstantArrayType(EltTy: ResTy, ArySize: LengthI, SizeExpr: nullptr,
3762	ASM: ArraySizeModifier::Normal,
3763	/*IndexTypeQuals*/ 0);
3764	SL = StringLiteral::Create(Ctx: Context, Str, Kind: StringLiteralKind::Ordinary,
3765	/*Pascal*/ false, Ty: ResTy, Loc);
3766	}
3767	}
3768
3769	return PredefinedExpr::Create(Ctx: Context, L: Loc, FNTy: ResTy, IK, IsTransparent: LangOpts.MicrosoftExt,
3770	SL);
3771	}
3772
3773	ExprResult Sema::BuildSYCLUniqueStableNameExpr(SourceLocation OpLoc,
3774	SourceLocation LParen,
3775	SourceLocation RParen,
3776	TypeSourceInfo *TSI) {
3777	return SYCLUniqueStableNameExpr::Create(Ctx: Context, OpLoc, LParen, RParen, TSI);
3778	}
3779
3780	ExprResult Sema::ActOnSYCLUniqueStableNameExpr(SourceLocation OpLoc,
3781	SourceLocation LParen,
3782	SourceLocation RParen,
3783	ParsedType ParsedTy) {
3784	TypeSourceInfo *TSI = nullptr;
3785	QualType Ty = GetTypeFromParser(Ty: ParsedTy, TInfo: &TSI);
3786
3787	if (Ty.isNull())
3788	return ExprError();
3789	if (!TSI)
3790	TSI = Context.getTrivialTypeSourceInfo(T: Ty, Loc: LParen);
3791
3792	return BuildSYCLUniqueStableNameExpr(OpLoc, LParen, RParen, TSI);
3793	}
3794
3795	ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) {
3796	return BuildPredefinedExpr(Loc, IK: getPredefinedExprKind(Kind));
3797	}
3798
3799	ExprResult Sema::ActOnCharacterConstant(const Token &Tok, Scope *UDLScope) {
3800	SmallString<16> CharBuffer;
3801	bool Invalid = false;
3802	StringRef ThisTok = PP.getSpelling(Tok, Buffer&: CharBuffer, Invalid: &Invalid);
3803	if (Invalid)
3804	return ExprError();
3805
3806	CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(),
3807	PP, Tok.getKind());
3808	if (Literal.hadError())
3809	return ExprError();
3810
3811	QualType Ty;
3812	if (Literal.isWide())
3813	Ty = Context.WideCharTy; // L'x' -> wchar_t in C and C++.
3814	else if (Literal.isUTF8() && getLangOpts().C23)
3815	Ty = Context.UnsignedCharTy; // u8'x' -> unsigned char in C23
3816	else if (Literal.isUTF8() && getLangOpts().Char8)
3817	Ty = Context.Char8Ty; // u8'x' -> char8_t when it exists.
3818	else if (Literal.isUTF16())
3819	Ty = Context.Char16Ty; // u'x' -> char16_t in C11 and C++11.
3820	else if (Literal.isUTF32())
3821	Ty = Context.Char32Ty; // U'x' -> char32_t in C11 and C++11.
3822	else if (!getLangOpts().CPlusPlus || Literal.isMultiChar())
3823	Ty = Context.IntTy; // 'x' -> int in C, 'wxyz' -> int in C++.
3824	else
3825	Ty = Context.CharTy; // 'x' -> char in C++;
3826	// u8'x' -> char in C11-C17 and in C++ without char8_t.
3827
3828	CharacterLiteralKind Kind = CharacterLiteralKind::Ascii;
3829	if (Literal.isWide())
3830	Kind = CharacterLiteralKind::Wide;
3831	else if (Literal.isUTF16())
3832	Kind = CharacterLiteralKind::UTF16;
3833	else if (Literal.isUTF32())
3834	Kind = CharacterLiteralKind::UTF32;
3835	else if (Literal.isUTF8())
3836	Kind = CharacterLiteralKind::UTF8;
3837
3838	Expr *Lit = new (Context) CharacterLiteral(Literal.getValue(), Kind, Ty,
3839	Tok.getLocation());
3840
3841	if (Literal.getUDSuffix().empty())
3842	return Lit;
3843
3844	// We're building a user-defined literal.
3845	IdentifierInfo *UDSuffix = &Context.Idents.get(Name: Literal.getUDSuffix());
3846	SourceLocation UDSuffixLoc =
3847	getUDSuffixLoc(S&: *this, TokLoc: Tok.getLocation(), Offset: Literal.getUDSuffixOffset());
3848
3849	// Make sure we're allowed user-defined literals here.
3850	if (!UDLScope)
3851	return ExprError(Diag(UDSuffixLoc, diag::err_invalid_character_udl));
3852
3853	// C++11 [lex.ext]p6: The literal L is treated as a call of the form
3854	// operator "" X (ch)
3855	return BuildCookedLiteralOperatorCall(S&: *this, Scope: UDLScope, UDSuffix, UDSuffixLoc,
3856	Args: Lit, LitEndLoc: Tok.getLocation());
3857	}
3858
3859	ExprResult Sema::ActOnIntegerConstant(SourceLocation Loc, uint64_t Val) {
3860	unsigned IntSize = Context.getTargetInfo().getIntWidth();
3861	return IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val),
3862	Context.IntTy, Loc);
3863	}
3864
3865	static Expr *BuildFloatingLiteral(Sema &S, NumericLiteralParser &Literal,
3866	QualType Ty, SourceLocation Loc) {
3867	const llvm::fltSemantics &Format = S.Context.getFloatTypeSemantics(T: Ty);
3868
3869	using llvm::APFloat;
3870	APFloat Val(Format);
3871
3872	APFloat::opStatus result = Literal.GetFloatValue(Result&: Val);
3873
3874	// Overflow is always an error, but underflow is only an error if
3875	// we underflowed to zero (APFloat reports denormals as underflow).
3876	if ((result & APFloat::opOverflow) ||
3877	((result & APFloat::opUnderflow) && Val.isZero())) {
3878	unsigned diagnostic;
3879	SmallString<20> buffer;
3880	if (result & APFloat::opOverflow) {
3881	diagnostic = diag::warn_float_overflow;
3882	APFloat::getLargest(Sem: Format).toString(Str&: buffer);
3883	} else {
3884	diagnostic = diag::warn_float_underflow;
3885	APFloat::getSmallest(Sem: Format).toString(Str&: buffer);
3886	}
3887
3888	S.Diag(Loc, DiagID: diagnostic)
3889	<< Ty
3890	<< StringRef(buffer.data(), buffer.size());
3891	}
3892
3893	bool isExact = (result == APFloat::opOK);
3894	return FloatingLiteral::Create(C: S.Context, V: Val, isexact: isExact, Type: Ty, L: Loc);
3895	}
3896
3897	bool Sema::CheckLoopHintExpr(Expr *E, SourceLocation Loc) {
3898	assert(E && "Invalid expression");
3899
3900	if (E->isValueDependent())
3901	return false;
3902
3903	QualType QT = E->getType();
3904	if (!QT->isIntegerType() || QT->isBooleanType() || QT->isCharType()) {
3905	Diag(E->getExprLoc(), diag::err_pragma_loop_invalid_argument_type) << QT;
3906	return true;
3907	}
3908
3909	llvm::APSInt ValueAPS;
3910	ExprResult R = VerifyIntegerConstantExpression(E, Result: &ValueAPS);
3911
3912	if (R.isInvalid())
3913	return true;
3914
3915	bool ValueIsPositive = ValueAPS.isStrictlyPositive();
3916	if (!ValueIsPositive || ValueAPS.getActiveBits() > 31) {
3917	Diag(E->getExprLoc(), diag::err_pragma_loop_invalid_argument_value)
3918	<< toString(ValueAPS, 10) << ValueIsPositive;
3919	return true;
3920	}
3921
3922	return false;
3923	}
3924
3925	ExprResult Sema::ActOnNumericConstant(const Token &Tok, Scope *UDLScope) {
3926	// Fast path for a single digit (which is quite common). A single digit
3927	// cannot have a trigraph, escaped newline, radix prefix, or suffix.
3928	if (Tok.getLength() == 1) {
3929	const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok);
3930	return ActOnIntegerConstant(Loc: Tok.getLocation(), Val: Val-'0');
3931	}
3932
3933	SmallString<128> SpellingBuffer;
3934	// NumericLiteralParser wants to overread by one character. Add padding to
3935	// the buffer in case the token is copied to the buffer. If getSpelling()
3936	// returns a StringRef to the memory buffer, it should have a null char at
3937	// the EOF, so it is also safe.
3938	SpellingBuffer.resize(N: Tok.getLength() + 1);
3939
3940	// Get the spelling of the token, which eliminates trigraphs, etc.
3941	bool Invalid = false;
3942	StringRef TokSpelling = PP.getSpelling(Tok, Buffer&: SpellingBuffer, Invalid: &Invalid);
3943	if (Invalid)
3944	return ExprError();
3945
3946	NumericLiteralParser Literal(TokSpelling, Tok.getLocation(),
3947	PP.getSourceManager(), PP.getLangOpts(),
3948	PP.getTargetInfo(), PP.getDiagnostics());
3949	if (Literal.hadError)
3950	return ExprError();
3951
3952	if (Literal.hasUDSuffix()) {
3953	// We're building a user-defined literal.
3954	const IdentifierInfo *UDSuffix = &Context.Idents.get(Name: Literal.getUDSuffix());
3955	SourceLocation UDSuffixLoc =
3956	getUDSuffixLoc(S&: *this, TokLoc: Tok.getLocation(), Offset: Literal.getUDSuffixOffset());
3957
3958	// Make sure we're allowed user-defined literals here.
3959	if (!UDLScope)
3960	return ExprError(Diag(UDSuffixLoc, diag::err_invalid_numeric_udl));
3961
3962	QualType CookedTy;
3963	if (Literal.isFloatingLiteral()) {
3964	// C++11 [lex.ext]p4: If S contains a literal operator with parameter type
3965	// long double, the literal is treated as a call of the form
3966	// operator "" X (f L)
3967	CookedTy = Context.LongDoubleTy;
3968	} else {
3969	// C++11 [lex.ext]p3: If S contains a literal operator with parameter type
3970	// unsigned long long, the literal is treated as a call of the form
3971	// operator "" X (n ULL)
3972	CookedTy = Context.UnsignedLongLongTy;
3973	}
3974
3975	DeclarationName OpName =
3976	Context.DeclarationNames.getCXXLiteralOperatorName(II: UDSuffix);
3977	DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
3978	OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
3979
3980	SourceLocation TokLoc = Tok.getLocation();
3981
3982	// Perform literal operator lookup to determine if we're building a raw
3983	// literal or a cooked one.
3984	LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName);
3985	switch (LookupLiteralOperator(S: UDLScope, R, ArgTys: CookedTy,
3986	/*AllowRaw*/ true, /*AllowTemplate*/ true,
3987	/*AllowStringTemplatePack*/ AllowStringTemplate: false,
3988	/*DiagnoseMissing*/ !Literal.isImaginary)) {
3989	case LOLR_ErrorNoDiagnostic:
3990	// Lookup failure for imaginary constants isn't fatal, there's still the
3991	// GNU extension producing _Complex types.
3992	break;
3993	case LOLR_Error:
3994	return ExprError();
3995	case LOLR_Cooked: {
3996	Expr *Lit;
3997	if (Literal.isFloatingLiteral()) {
3998	Lit = BuildFloatingLiteral(S&: *this, Literal, Ty: CookedTy, Loc: Tok.getLocation());
3999	} else {
4000	llvm::APInt ResultVal(Context.getTargetInfo().getLongLongWidth(), 0);
4001	if (Literal.GetIntegerValue(ResultVal))
4002	Diag(Tok.getLocation(), diag::err_integer_literal_too_large)
4003	<< /* Unsigned */ 1;
4004	Lit = IntegerLiteral::Create(C: Context, V: ResultVal, type: CookedTy,
4005	l: Tok.getLocation());
4006	}
4007	return BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args: Lit, LitEndLoc: TokLoc);
4008	}
4009
4010	case LOLR_Raw: {
4011	// C++11 [lit.ext]p3, p4: If S contains a raw literal operator, the
4012	// literal is treated as a call of the form
4013	// operator "" X ("n")
4014	unsigned Length = Literal.getUDSuffixOffset();
4015	QualType StrTy = Context.getConstantArrayType(
4016	EltTy: Context.adjustStringLiteralBaseType(StrLTy: Context.CharTy.withConst()),
4017	ArySize: llvm::APInt(32, Length + 1), SizeExpr: nullptr, ASM: ArraySizeModifier::Normal, IndexTypeQuals: 0);
4018	Expr *Lit =
4019	StringLiteral::Create(Ctx: Context, Str: StringRef(TokSpelling.data(), Length),
4020	Kind: StringLiteralKind::Ordinary,
4021	/*Pascal*/ false, Ty: StrTy, Loc: &TokLoc, NumConcatenated: 1);
4022	return BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args: Lit, LitEndLoc: TokLoc);
4023	}
4024
4025	case LOLR_Template: {
4026	// C++11 [lit.ext]p3, p4: Otherwise (S contains a literal operator
4027	// template), L is treated as a call fo the form
4028	// operator "" X <'c1', 'c2', ... 'ck'>()
4029	// where n is the source character sequence c1 c2 ... ck.
4030	TemplateArgumentListInfo ExplicitArgs;
4031	unsigned CharBits = Context.getIntWidth(T: Context.CharTy);
4032	bool CharIsUnsigned = Context.CharTy->isUnsignedIntegerType();
4033	llvm::APSInt Value(CharBits, CharIsUnsigned);
4034	for (unsigned I = 0, N = Literal.getUDSuffixOffset(); I != N; ++I) {
4035	Value = TokSpelling[I];
4036	TemplateArgument Arg(Context, Value, Context.CharTy);
4037	TemplateArgumentLocInfo ArgInfo;
4038	ExplicitArgs.addArgument(Loc: TemplateArgumentLoc(Arg, ArgInfo));
4039	}
4040	return BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args: std::nullopt, LitEndLoc: TokLoc,
4041	ExplicitTemplateArgs: &ExplicitArgs);
4042	}
4043	case LOLR_StringTemplatePack:
4044	llvm_unreachable("unexpected literal operator lookup result");
4045	}
4046	}
4047
4048	Expr *Res;
4049
4050	if (Literal.isFixedPointLiteral()) {
4051	QualType Ty;
4052
4053	if (Literal.isAccum) {
4054	if (Literal.isHalf) {
4055	Ty = Context.ShortAccumTy;
4056	} else if (Literal.isLong) {
4057	Ty = Context.LongAccumTy;
4058	} else {
4059	Ty = Context.AccumTy;
4060	}
4061	} else if (Literal.isFract) {
4062	if (Literal.isHalf) {
4063	Ty = Context.ShortFractTy;
4064	} else if (Literal.isLong) {
4065	Ty = Context.LongFractTy;
4066	} else {
4067	Ty = Context.FractTy;
4068	}
4069	}
4070
4071	if (Literal.isUnsigned) Ty = Context.getCorrespondingUnsignedType(T: Ty);
4072
4073	bool isSigned = !Literal.isUnsigned;
4074	unsigned scale = Context.getFixedPointScale(Ty);
4075	unsigned bit_width = Context.getTypeInfo(T: Ty).Width;
4076
4077	llvm::APInt Val(bit_width, 0, isSigned);
4078	bool Overflowed = Literal.GetFixedPointValue(StoreVal&: Val, Scale: scale);
4079	bool ValIsZero = Val.isZero() && !Overflowed;
4080
4081	auto MaxVal = Context.getFixedPointMax(Ty).getValue();
4082	if (Literal.isFract && Val == MaxVal + 1 && !ValIsZero)
4083	// Clause 6.4.4 - The value of a constant shall be in the range of
4084	// representable values for its type, with exception for constants of a
4085	// fract type with a value of exactly 1; such a constant shall denote
4086	// the maximal value for the type.
4087	--Val;
4088	else if (Val.ugt(MaxVal) || Overflowed)
4089	Diag(Tok.getLocation(), diag::err_too_large_for_fixed_point);
4090
4091	Res = FixedPointLiteral::CreateFromRawInt(C: Context, V: Val, type: Ty,
4092	l: Tok.getLocation(), Scale: scale);
4093	} else if (Literal.isFloatingLiteral()) {
4094	QualType Ty;
4095	if (Literal.isHalf){
4096	if (getOpenCLOptions().isAvailableOption(Ext: "cl_khr_fp16", LO: getLangOpts()))
4097	Ty = Context.HalfTy;
4098	else {
4099	Diag(Tok.getLocation(), diag::err_half_const_requires_fp16);
4100	return ExprError();
4101	}
4102	} else if (Literal.isFloat)
4103	Ty = Context.FloatTy;
4104	else if (Literal.isLong)
4105	Ty = Context.LongDoubleTy;
4106	else if (Literal.isFloat16)
4107	Ty = Context.Float16Ty;
4108	else if (Literal.isFloat128)
4109	Ty = Context.Float128Ty;
4110	else
4111	Ty = Context.DoubleTy;
4112
4113	Res = BuildFloatingLiteral(S&: *this, Literal, Ty, Loc: Tok.getLocation());
4114
4115	if (Ty == Context.DoubleTy) {
4116	if (getLangOpts().SinglePrecisionConstants) {
4117	if (Ty->castAs<BuiltinType>()->getKind() != BuiltinType::Float) {
4118	Res = ImpCastExprToType(E: Res, Type: Context.FloatTy, CK: CK_FloatingCast).get();
4119	}
4120	} else if (getLangOpts().OpenCL && !getOpenCLOptions().isAvailableOption(
4121	Ext: "cl_khr_fp64", LO: getLangOpts())) {
4122	// Impose single-precision float type when cl_khr_fp64 is not enabled.
4123	Diag(Tok.getLocation(), diag::warn_double_const_requires_fp64)
4124	<< (getLangOpts().getOpenCLCompatibleVersion() >= 300);
4125	Res = ImpCastExprToType(E: Res, Type: Context.FloatTy, CK: CK_FloatingCast).get();
4126	}
4127	}
4128	} else if (!Literal.isIntegerLiteral()) {
4129	return ExprError();
4130	} else {
4131	QualType Ty;
4132
4133	// 'z/uz' literals are a C++23 feature.
4134	if (Literal.isSizeT)
4135	Diag(Tok.getLocation(), getLangOpts().CPlusPlus
4136	? getLangOpts().CPlusPlus23
4137	? diag::warn_cxx20_compat_size_t_suffix
4138	: diag::ext_cxx23_size_t_suffix
4139	: diag::err_cxx23_size_t_suffix);
4140
4141	// 'wb/uwb' literals are a C23 feature. We support _BitInt as a type in C++,
4142	// but we do not currently support the suffix in C++ mode because it's not
4143	// entirely clear whether WG21 will prefer this suffix to return a library
4144	// type such as std::bit_int instead of returning a _BitInt.
4145	if (Literal.isBitInt && !getLangOpts().CPlusPlus)
4146	PP.Diag(Tok.getLocation(), getLangOpts().C23
4147	? diag::warn_c23_compat_bitint_suffix
4148	: diag::ext_c23_bitint_suffix);
4149
4150	// Get the value in the widest-possible width. What is "widest" depends on
4151	// whether the literal is a bit-precise integer or not. For a bit-precise
4152	// integer type, try to scan the source to determine how many bits are
4153	// needed to represent the value. This may seem a bit expensive, but trying
4154	// to get the integer value from an overly-wide APInt is *extremely*
4155	// expensive, so the naive approach of assuming
4156	// llvm::IntegerType::MAX_INT_BITS is a big performance hit.
4157	unsigned BitsNeeded =
4158	Literal.isBitInt ? llvm::APInt::getSufficientBitsNeeded(
4159	Str: Literal.getLiteralDigits(), Radix: Literal.getRadix())
4160	: Context.getTargetInfo().getIntMaxTWidth();
4161	llvm::APInt ResultVal(BitsNeeded, 0);
4162
4163	if (Literal.GetIntegerValue(Val&: ResultVal)) {
4164	// If this value didn't fit into uintmax_t, error and force to ull.
4165	Diag(Tok.getLocation(), diag::err_integer_literal_too_large)
4166	<< /* Unsigned */ 1;
4167	Ty = Context.UnsignedLongLongTy;
4168	assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() &&
4169	"long long is not intmax_t?");
4170	} else {
4171	// If this value fits into a ULL, try to figure out what else it fits into
4172	// according to the rules of C99 6.4.4.1p5.
4173
4174	// Octal, Hexadecimal, and integers with a U suffix are allowed to
4175	// be an unsigned int.
4176	bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10;
4177
4178	// Check from smallest to largest, picking the smallest type we can.
4179	unsigned Width = 0;
4180
4181	// Microsoft specific integer suffixes are explicitly sized.
4182	if (Literal.MicrosoftInteger) {
4183	if (Literal.MicrosoftInteger == 8 && !Literal.isUnsigned) {
4184	Width = 8;
4185	Ty = Context.CharTy;
4186	} else {
4187	Width = Literal.MicrosoftInteger;
4188	Ty = Context.getIntTypeForBitwidth(DestWidth: Width,
4189	/*Signed=*/!Literal.isUnsigned);
4190	}
4191	}
4192
4193	// Bit-precise integer literals are automagically-sized based on the
4194	// width required by the literal.
4195	if (Literal.isBitInt) {
4196	// The signed version has one more bit for the sign value. There are no
4197	// zero-width bit-precise integers, even if the literal value is 0.
4198	Width = std::max(a: ResultVal.getActiveBits(), b: 1u) +
4199	(Literal.isUnsigned ? 0u : 1u);
4200
4201	// Diagnose if the width of the constant is larger than BITINT_MAXWIDTH,
4202	// and reset the type to the largest supported width.
4203	unsigned int MaxBitIntWidth =
4204	Context.getTargetInfo().getMaxBitIntWidth();
4205	if (Width > MaxBitIntWidth) {
4206	Diag(Tok.getLocation(), diag::err_integer_literal_too_large)
4207	<< Literal.isUnsigned;
4208	Width = MaxBitIntWidth;
4209	}
4210
4211	// Reset the result value to the smaller APInt and select the correct
4212	// type to be used. Note, we zext even for signed values because the
4213	// literal itself is always an unsigned value (a preceeding - is a
4214	// unary operator, not part of the literal).
4215	ResultVal = ResultVal.zextOrTrunc(width: Width);
4216	Ty = Context.getBitIntType(Unsigned: Literal.isUnsigned, NumBits: Width);
4217	}
4218
4219	// Check C++23 size_t literals.
4220	if (Literal.isSizeT) {
4221	assert(!Literal.MicrosoftInteger &&
4222	"size_t literals can't be Microsoft literals");
4223	unsigned SizeTSize = Context.getTargetInfo().getTypeWidth(
4224	T: Context.getTargetInfo().getSizeType());
4225
4226	// Does it fit in size_t?
4227	if (ResultVal.isIntN(N: SizeTSize)) {
4228	// Does it fit in ssize_t?
4229	if (!Literal.isUnsigned && ResultVal[SizeTSize - 1] == 0)
4230	Ty = Context.getSignedSizeType();
4231	else if (AllowUnsigned)
4232	Ty = Context.getSizeType();
4233	Width = SizeTSize;
4234	}
4235	}
4236
4237	if (Ty.isNull() && !Literal.isLong && !Literal.isLongLong &&
4238	!Literal.isSizeT) {
4239	// Are int/unsigned possibilities?
4240	unsigned IntSize = Context.getTargetInfo().getIntWidth();
4241
4242	// Does it fit in a unsigned int?
4243	if (ResultVal.isIntN(N: IntSize)) {
4244	// Does it fit in a signed int?
4245	if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0)
4246	Ty = Context.IntTy;
4247	else if (AllowUnsigned)
4248	Ty = Context.UnsignedIntTy;
4249	Width = IntSize;
4250	}
4251	}
4252
4253	// Are long/unsigned long possibilities?
4254	if (Ty.isNull() && !Literal.isLongLong && !Literal.isSizeT) {
4255	unsigned LongSize = Context.getTargetInfo().getLongWidth();
4256
4257	// Does it fit in a unsigned long?
4258	if (ResultVal.isIntN(N: LongSize)) {
4259	// Does it fit in a signed long?
4260	if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0)
4261	Ty = Context.LongTy;
4262	else if (AllowUnsigned)
4263	Ty = Context.UnsignedLongTy;
4264	// Check according to the rules of C90 6.1.3.2p5. C++03 [lex.icon]p2
4265	// is compatible.
4266	else if (!getLangOpts().C99 && !getLangOpts().CPlusPlus11) {
4267	const unsigned LongLongSize =
4268	Context.getTargetInfo().getLongLongWidth();
4269	Diag(Tok.getLocation(),
4270	getLangOpts().CPlusPlus
4271	? Literal.isLong
4272	? diag::warn_old_implicitly_unsigned_long_cxx
4273	: /*C++98 UB*/ diag::
4274	ext_old_implicitly_unsigned_long_cxx
4275	: diag::warn_old_implicitly_unsigned_long)
4276	<< (LongLongSize > LongSize ? /*will have type 'long long'*/ 0
4277	: /*will be ill-formed*/ 1);
4278	Ty = Context.UnsignedLongTy;
4279	}
4280	Width = LongSize;
4281	}
4282	}
4283
4284	// Check long long if needed.
4285	if (Ty.isNull() && !Literal.isSizeT) {
4286	unsigned LongLongSize = Context.getTargetInfo().getLongLongWidth();
4287
4288	// Does it fit in a unsigned long long?
4289	if (ResultVal.isIntN(N: LongLongSize)) {
4290	// Does it fit in a signed long long?
4291	// To be compatible with MSVC, hex integer literals ending with the
4292	// LL or i64 suffix are always signed in Microsoft mode.
4293	if (!Literal.isUnsigned && (ResultVal[LongLongSize-1] == 0 ||
4294	(getLangOpts().MSVCCompat && Literal.isLongLong)))
4295	Ty = Context.LongLongTy;
4296	else if (AllowUnsigned)
4297	Ty = Context.UnsignedLongLongTy;
4298	Width = LongLongSize;
4299
4300	// 'long long' is a C99 or C++11 feature, whether the literal
4301	// explicitly specified 'long long' or we needed the extra width.
4302	if (getLangOpts().CPlusPlus)
4303	Diag(Tok.getLocation(), getLangOpts().CPlusPlus11
4304	? diag::warn_cxx98_compat_longlong
4305	: diag::ext_cxx11_longlong);
4306	else if (!getLangOpts().C99)
4307	Diag(Tok.getLocation(), diag::ext_c99_longlong);
4308	}
4309	}
4310
4311	// If we still couldn't decide a type, we either have 'size_t' literal
4312	// that is out of range, or a decimal literal that does not fit in a
4313	// signed long long and has no U suffix.
4314	if (Ty.isNull()) {
4315	if (Literal.isSizeT)
4316	Diag(Tok.getLocation(), diag::err_size_t_literal_too_large)
4317	<< Literal.isUnsigned;
4318	else
4319	Diag(Tok.getLocation(),
4320	diag::ext_integer_literal_too_large_for_signed);
4321	Ty = Context.UnsignedLongLongTy;
4322	Width = Context.getTargetInfo().getLongLongWidth();
4323	}
4324
4325	if (ResultVal.getBitWidth() != Width)
4326	ResultVal = ResultVal.trunc(width: Width);
4327	}
4328	Res = IntegerLiteral::Create(C: Context, V: ResultVal, type: Ty, l: Tok.getLocation());
4329	}
4330
4331	// If this is an imaginary literal, create the ImaginaryLiteral wrapper.
4332	if (Literal.isImaginary) {
4333	Res = new (Context) ImaginaryLiteral(Res,
4334	Context.getComplexType(T: Res->getType()));
4335
4336	Diag(Tok.getLocation(), diag::ext_imaginary_constant);
4337	}
4338	return Res;
4339	}
4340
4341	ExprResult Sema::ActOnParenExpr(SourceLocation L, SourceLocation R, Expr *E) {
4342	assert(E && "ActOnParenExpr() missing expr");
4343	QualType ExprTy = E->getType();
4344	if (getLangOpts().ProtectParens && CurFPFeatures.getAllowFPReassociate() &&
4345	!E->isLValue() && ExprTy->hasFloatingRepresentation())
4346	return BuildBuiltinCallExpr(R, Builtin::BI__arithmetic_fence, E);
4347	return new (Context) ParenExpr(L, R, E);
4348	}
4349
4350	static bool CheckVecStepTraitOperandType(Sema &S, QualType T,
4351	SourceLocation Loc,
4352	SourceRange ArgRange) {
4353	// [OpenCL 1.1 6.11.12] "The vec_step built-in function takes a built-in
4354	// scalar or vector data type argument..."
4355	// Every built-in scalar type (OpenCL 1.1 6.1.1) is either an arithmetic
4356	// type (C99 6.2.5p18) or void.
4357	if (!(T->isArithmeticType() || T->isVoidType() || T->isVectorType())) {
4358	S.Diag(Loc, diag::err_vecstep_non_scalar_vector_type)
4359	<< T << ArgRange;
4360	return true;
4361	}
4362
4363	assert((T->isVoidType() || !T->isIncompleteType()) &&
4364	"Scalar types should always be complete");
4365	return false;
4366	}
4367
4368	static bool CheckVectorElementsTraitOperandType(Sema &S, QualType T,
4369	SourceLocation Loc,
4370	SourceRange ArgRange) {
4371	// builtin_vectorelements supports both fixed-sized and scalable vectors.
4372	if (!T->isVectorType() && !T->isSizelessVectorType())
4373	return S.Diag(Loc, diag::err_builtin_non_vector_type)
4374	<< ""
4375	<< "__builtin_vectorelements" << T << ArgRange;
4376
4377	return false;
4378	}
4379
4380	static bool CheckExtensionTraitOperandType(Sema &S, QualType T,
4381	SourceLocation Loc,
4382	SourceRange ArgRange,
4383	UnaryExprOrTypeTrait TraitKind) {
4384	// Invalid types must be hard errors for SFINAE in C++.
4385	if (S.LangOpts.CPlusPlus)
4386	return true;
4387
4388	// C99 6.5.3.4p1:
4389	if (T->isFunctionType() &&
4390	(TraitKind == UETT_SizeOf || TraitKind == UETT_AlignOf ||
4391	TraitKind == UETT_PreferredAlignOf)) {
4392	// sizeof(function)/alignof(function) is allowed as an extension.
4393	S.Diag(Loc, diag::ext_sizeof_alignof_function_type)
4394	<< getTraitSpelling(TraitKind) << ArgRange;
4395	return false;
4396	}
4397
4398	// Allow sizeof(void)/alignof(void) as an extension, unless in OpenCL where
4399	// this is an error (OpenCL v1.1 s6.3.k)
4400	if (T->isVoidType()) {
4401	unsigned DiagID = S.LangOpts.OpenCL ? diag::err_opencl_sizeof_alignof_type
4402	: diag::ext_sizeof_alignof_void_type;
4403	S.Diag(Loc, DiagID) << getTraitSpelling(T: TraitKind) << ArgRange;
4404	return false;
4405	}
4406
4407	return true;
4408	}
4409
4410	static bool CheckObjCTraitOperandConstraints(Sema &S, QualType T,
4411	SourceLocation Loc,
4412	SourceRange ArgRange,
4413	UnaryExprOrTypeTrait TraitKind) {
4414	// Reject sizeof(interface) and sizeof(interface<proto>) if the
4415	// runtime doesn't allow it.
4416	if (!S.LangOpts.ObjCRuntime.allowsSizeofAlignof() && T->isObjCObjectType()) {
4417	S.Diag(Loc, diag::err_sizeof_nonfragile_interface)
4418	<< T << (TraitKind == UETT_SizeOf)
4419	<< ArgRange;
4420	return true;
4421	}
4422
4423	return false;
4424	}
4425
4426	/// Check whether E is a pointer from a decayed array type (the decayed
4427	/// pointer type is equal to T) and emit a warning if it is.
4428	static void warnOnSizeofOnArrayDecay(Sema &S, SourceLocation Loc, QualType T,
4429	const Expr *E) {
4430	// Don't warn if the operation changed the type.
4431	if (T != E->getType())
4432	return;
4433
4434	// Now look for array decays.
4435	const auto *ICE = dyn_cast<ImplicitCastExpr>(Val: E);
4436	if (!ICE || ICE->getCastKind() != CK_ArrayToPointerDecay)
4437	return;
4438
4439	S.Diag(Loc, diag::warn_sizeof_array_decay) << ICE->getSourceRange()
4440	<< ICE->getType()
4441	<< ICE->getSubExpr()->getType();
4442	}
4443
4444	/// Check the constraints on expression operands to unary type expression
4445	/// and type traits.
4446	///
4447	/// Completes any types necessary and validates the constraints on the operand
4448	/// expression. The logic mostly mirrors the type-based overload, but may modify
4449	/// the expression as it completes the type for that expression through template
4450	/// instantiation, etc.
4451	bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E,
4452	UnaryExprOrTypeTrait ExprKind) {
4453	QualType ExprTy = E->getType();
4454	assert(!ExprTy->isReferenceType());
4455
4456	bool IsUnevaluatedOperand =
4457	(ExprKind == UETT_SizeOf || ExprKind == UETT_DataSizeOf ||
4458	ExprKind == UETT_AlignOf || ExprKind == UETT_PreferredAlignOf ||
4459	ExprKind == UETT_VecStep);
4460	if (IsUnevaluatedOperand) {
4461	ExprResult Result = CheckUnevaluatedOperand(E);
4462	if (Result.isInvalid())
4463	return true;
4464	E = Result.get();
4465	}
4466
4467	// The operand for sizeof and alignof is in an unevaluated expression context,
4468	// so side effects could result in unintended consequences.
4469	// Exclude instantiation-dependent expressions, because 'sizeof' is sometimes
4470	// used to build SFINAE gadgets.
4471	// FIXME: Should we consider instantiation-dependent operands to 'alignof'?
4472	if (IsUnevaluatedOperand && !inTemplateInstantiation() &&
4473	!E->isInstantiationDependent() &&
4474	!E->getType()->isVariableArrayType() &&
4475	E->HasSideEffects(Context, false))
4476	Diag(E->getExprLoc(), diag::warn_side_effects_unevaluated_context);
4477
4478	if (ExprKind == UETT_VecStep)
4479	return CheckVecStepTraitOperandType(*this, ExprTy, E->getExprLoc(),
4480	E->getSourceRange());
4481
4482	if (ExprKind == UETT_VectorElements)
4483	return CheckVectorElementsTraitOperandType(*this, ExprTy, E->getExprLoc(),
4484	E->getSourceRange());
4485
4486	// Explicitly list some types as extensions.
4487	if (!CheckExtensionTraitOperandType(*this, ExprTy, E->getExprLoc(),
4488	E->getSourceRange(), ExprKind))
4489	return false;
4490
4491	// WebAssembly tables are always illegal operands to unary expressions and
4492	// type traits.
4493	if (Context.getTargetInfo().getTriple().isWasm() &&
4494	E->getType()->isWebAssemblyTableType()) {
4495	Diag(E->getExprLoc(), diag::err_wasm_table_invalid_uett_operand)
4496	<< getTraitSpelling(ExprKind);
4497	return true;
4498	}
4499
4500	// 'alignof' applied to an expression only requires the base element type of
4501	// the expression to be complete. 'sizeof' requires the expression's type to
4502	// be complete (and will attempt to complete it if it's an array of unknown
4503	// bound).
4504	if (ExprKind == UETT_AlignOf || ExprKind == UETT_PreferredAlignOf) {
4505	if (RequireCompleteSizedType(
4506	E->getExprLoc(), Context.getBaseElementType(E->getType()),
4507	diag::err_sizeof_alignof_incomplete_or_sizeless_type,
4508	getTraitSpelling(ExprKind), E->getSourceRange()))
4509	return true;
4510	} else {
4511	if (RequireCompleteSizedExprType(
4512	E, diag::err_sizeof_alignof_incomplete_or_sizeless_type,
4513	getTraitSpelling(ExprKind), E->getSourceRange()))
4514	return true;
4515	}
4516
4517	// Completing the expression's type may have changed it.
4518	ExprTy = E->getType();
4519	assert(!ExprTy->isReferenceType());
4520
4521	if (ExprTy->isFunctionType()) {
4522	Diag(E->getExprLoc(), diag::err_sizeof_alignof_function_type)
4523	<< getTraitSpelling(ExprKind) << E->getSourceRange();
4524	return true;
4525	}
4526
4527	if (CheckObjCTraitOperandConstraints(*this, ExprTy, E->getExprLoc(),
4528	E->getSourceRange(), ExprKind))
4529	return true;
4530
4531	if (ExprKind == UETT_SizeOf) {
4532	if (const auto *DeclRef = dyn_cast<DeclRefExpr>(Val: E->IgnoreParens())) {
4533	if (const auto *PVD = dyn_cast<ParmVarDecl>(Val: DeclRef->getFoundDecl())) {
4534	QualType OType = PVD->getOriginalType();
4535	QualType Type = PVD->getType();
4536	if (Type->isPointerType() && OType->isArrayType()) {
4537	Diag(E->getExprLoc(), diag::warn_sizeof_array_param)
4538	<< Type << OType;
4539	Diag(PVD->getLocation(), diag::note_declared_at);
4540	}
4541	}
4542	}
4543
4544	// Warn on "sizeof(array op x)" and "sizeof(x op array)", where the array
4545	// decays into a pointer and returns an unintended result. This is most
4546	// likely a typo for "sizeof(array) op x".
4547	if (const auto *BO = dyn_cast<BinaryOperator>(Val: E->IgnoreParens())) {
4548	warnOnSizeofOnArrayDecay(*this, BO->getOperatorLoc(), BO->getType(),
4549	BO->getLHS());
4550	warnOnSizeofOnArrayDecay(*this, BO->getOperatorLoc(), BO->getType(),
4551	BO->getRHS());
4552	}
4553	}
4554
4555	return false;
4556	}
4557
4558	static bool CheckAlignOfExpr(Sema &S, Expr *E, UnaryExprOrTypeTrait ExprKind) {
4559	// Cannot know anything else if the expression is dependent.
4560	if (E->isTypeDependent())
4561	return false;
4562
4563	if (E->getObjectKind() == OK_BitField) {
4564	S.Diag(E->getExprLoc(), diag::err_sizeof_alignof_typeof_bitfield)
4565	<< 1 << E->getSourceRange();
4566	return true;
4567	}
4568
4569	ValueDecl *D = nullptr;
4570	Expr *Inner = E->IgnoreParens();
4571	if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: Inner)) {
4572	D = DRE->getDecl();
4573	} else if (MemberExpr *ME = dyn_cast<MemberExpr>(Val: Inner)) {
4574	D = ME->getMemberDecl();
4575	}
4576
4577	// If it's a field, require the containing struct to have a
4578	// complete definition so that we can compute the layout.
4579	//
4580	// This can happen in C++11 onwards, either by naming the member
4581	// in a way that is not transformed into a member access expression
4582	// (in an unevaluated operand, for instance), or by naming the member
4583	// in a trailing-return-type.
4584	//
4585	// For the record, since __alignof__ on expressions is a GCC
4586	// extension, GCC seems to permit this but always gives the
4587	// nonsensical answer 0.
4588	//
4589	// We don't really need the layout here --- we could instead just
4590	// directly check for all the appropriate alignment-lowing
4591	// attributes --- but that would require duplicating a lot of
4592	// logic that just isn't worth duplicating for such a marginal
4593	// use-case.
4594	if (FieldDecl *FD = dyn_cast_or_null<FieldDecl>(Val: D)) {
4595	// Fast path this check, since we at least know the record has a
4596	// definition if we can find a member of it.
4597	if (!FD->getParent()->isCompleteDefinition()) {
4598	S.Diag(E->getExprLoc(), diag::err_alignof_member_of_incomplete_type)
4599	<< E->getSourceRange();
4600	return true;
4601	}
4602
4603	// Otherwise, if it's a field, and the field doesn't have
4604	// reference type, then it must have a complete type (or be a
4605	// flexible array member, which we explicitly want to
4606	// white-list anyway), which makes the following checks trivial.
4607	if (!FD->getType()->isReferenceType())
4608	return false;
4609	}
4610
4611	return S.CheckUnaryExprOrTypeTraitOperand(E, ExprKind);
4612	}
4613
4614	bool Sema::CheckVecStepExpr(Expr *E) {
4615	E = E->IgnoreParens();
4616
4617	// Cannot know anything else if the expression is dependent.
4618	if (E->isTypeDependent())
4619	return false;
4620
4621	return CheckUnaryExprOrTypeTraitOperand(E, ExprKind: UETT_VecStep);
4622	}
4623
4624	static void captureVariablyModifiedType(ASTContext &Context, QualType T,
4625	CapturingScopeInfo *CSI) {
4626	assert(T->isVariablyModifiedType());
4627	assert(CSI != nullptr);
4628
4629	// We're going to walk down into the type and look for VLA expressions.
4630	do {
4631	const Type *Ty = T.getTypePtr();
4632	switch (Ty->getTypeClass()) {
4633	#define TYPE(Class, Base)
4634	#define ABSTRACT_TYPE(Class, Base)
4635	#define NON_CANONICAL_TYPE(Class, Base)
4636	#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4637	#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)
4638	#include "clang/AST/TypeNodes.inc"
4639	T = QualType();
4640	break;
4641	// These types are never variably-modified.
4642	case Type::Builtin:
4643	case Type::Complex:
4644	case Type::Vector:
4645	case Type::ExtVector:
4646	case Type::ConstantMatrix:
4647	case Type::Record:
4648	case Type::Enum:
4649	case Type::TemplateSpecialization:
4650	case Type::ObjCObject:
4651	case Type::ObjCInterface:
4652	case Type::ObjCObjectPointer:
4653	case Type::ObjCTypeParam:
4654	case Type::Pipe:
4655	case Type::BitInt:
4656	llvm_unreachable("type class is never variably-modified!");
4657	case Type::Elaborated:
4658	T = cast<ElaboratedType>(Ty)->getNamedType();
4659	break;
4660	case Type::Adjusted:
4661	T = cast<AdjustedType>(Ty)->getOriginalType();
4662	break;
4663	case Type::Decayed:
4664	T = cast<DecayedType>(Ty)->getPointeeType();
4665	break;
4666	case Type::Pointer:
4667	T = cast<PointerType>(Ty)->getPointeeType();
4668	break;
4669	case Type::BlockPointer:
4670	T = cast<BlockPointerType>(Ty)->getPointeeType();
4671	break;
4672	case Type::LValueReference:
4673	case Type::RValueReference:
4674	T = cast<ReferenceType>(Ty)->getPointeeType();
4675	break;
4676	case Type::MemberPointer:
4677	T = cast<MemberPointerType>(Ty)->getPointeeType();
4678	break;
4679	case Type::ConstantArray:
4680	case Type::IncompleteArray:
4681	// Losing element qualification here is fine.
4682	T = cast<ArrayType>(Ty)->getElementType();
4683	break;
4684	case Type::VariableArray: {
4685	// Losing element qualification here is fine.
4686	const VariableArrayType *VAT = cast<VariableArrayType>(Ty);
4687
4688	// Unknown size indication requires no size computation.
4689	// Otherwise, evaluate and record it.
4690	auto Size = VAT->getSizeExpr();
4691	if (Size && !CSI->isVLATypeCaptured(VAT) &&
4692	(isa<CapturedRegionScopeInfo>(CSI) || isa<LambdaScopeInfo>(CSI)))
4693	CSI->addVLATypeCapture(Loc: Size->getExprLoc(), VLAType: VAT, CaptureType: Context.getSizeType());
4694
4695	T = VAT->getElementType();
4696	break;
4697	}
4698	case Type::FunctionProto:
4699	case Type::FunctionNoProto:
4700	T = cast<FunctionType>(Ty)->getReturnType();
4701	break;
4702	case Type::Paren:
4703	case Type::TypeOf:
4704	case Type::UnaryTransform:
4705	case Type::Attributed:
4706	case Type::BTFTagAttributed:
4707	case Type::SubstTemplateTypeParm:
4708	case Type::MacroQualified:
4709	// Keep walking after single level desugaring.
4710	T = T.getSingleStepDesugaredType(Context);
4711	break;
4712	case Type::Typedef:
4713	T = cast<TypedefType>(Ty)->desugar();
4714	break;
4715	case Type::Decltype:
4716	T = cast<DecltypeType>(Ty)->desugar();
4717	break;
4718	case Type::PackIndexing:
4719	T = cast<PackIndexingType>(Ty)->desugar();
4720	break;
4721	case Type::Using:
4722	T = cast<UsingType>(Ty)->desugar();
4723	break;
4724	case Type::Auto:
4725	case Type::DeducedTemplateSpecialization:
4726	T = cast<DeducedType>(Ty)->getDeducedType();
4727	break;
4728	case Type::TypeOfExpr:
4729	T = cast<TypeOfExprType>(Ty)->getUnderlyingExpr()->getType();
4730	break;
4731	case Type::Atomic:
4732	T = cast<AtomicType>(Ty)->getValueType();
4733	break;
4734	}
4735	} while (!T.isNull() && T->isVariablyModifiedType());
4736	}
4737
4738	/// Check the constraints on operands to unary expression and type
4739	/// traits.
4740	///
4741	/// This will complete any types necessary, and validate the various constraints
4742	/// on those operands.
4743	///
4744	/// The UsualUnaryConversions() function is *not* called by this routine.
4745	/// C99 6.3.2.1p[2-4] all state:
4746	/// Except when it is the operand of the sizeof operator ...
4747	///
4748	/// C++ [expr.sizeof]p4
4749	/// The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4750	/// standard conversions are not applied to the operand of sizeof.
4751	///
4752	/// This policy is followed for all of the unary trait expressions.
4753	bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType ExprType,
4754	SourceLocation OpLoc,
4755	SourceRange ExprRange,
4756	UnaryExprOrTypeTrait ExprKind,
4757	StringRef KWName) {
4758	if (ExprType->isDependentType())
4759	return false;
4760
4761	// C++ [expr.sizeof]p2:
4762	// When applied to a reference or a reference type, the result
4763	// is the size of the referenced type.
4764	// C++11 [expr.alignof]p3:
4765	// When alignof is applied to a reference type, the result
4766	// shall be the alignment of the referenced type.
4767	if (const ReferenceType *Ref = ExprType->getAs<ReferenceType>())
4768	ExprType = Ref->getPointeeType();
4769
4770	// C11 6.5.3.4/3, C++11 [expr.alignof]p3:
4771	// When alignof or _Alignof is applied to an array type, the result
4772	// is the alignment of the element type.
4773	if (ExprKind == UETT_AlignOf || ExprKind == UETT_PreferredAlignOf ||
4774	ExprKind == UETT_OpenMPRequiredSimdAlign)
4775	ExprType = Context.getBaseElementType(QT: ExprType);
4776
4777	if (ExprKind == UETT_VecStep)
4778	return CheckVecStepTraitOperandType(S&: *this, T: ExprType, Loc: OpLoc, ArgRange: ExprRange);
4779
4780	if (ExprKind == UETT_VectorElements)
4781	return CheckVectorElementsTraitOperandType(S&: *this, T: ExprType, Loc: OpLoc,
4782	ArgRange: ExprRange);
4783
4784	// Explicitly list some types as extensions.
4785	if (!CheckExtensionTraitOperandType(S&: *this, T: ExprType, Loc: OpLoc, ArgRange: ExprRange,
4786	TraitKind: ExprKind))
4787	return false;
4788
4789	if (RequireCompleteSizedType(
4790	OpLoc, ExprType, diag::err_sizeof_alignof_incomplete_or_sizeless_type,
4791	KWName, ExprRange))
4792	return true;
4793
4794	if (ExprType->isFunctionType()) {
4795	Diag(OpLoc, diag::err_sizeof_alignof_function_type) << KWName << ExprRange;
4796	return true;
4797	}
4798
4799	// WebAssembly tables are always illegal operands to unary expressions and
4800	// type traits.
4801	if (Context.getTargetInfo().getTriple().isWasm() &&
4802	ExprType->isWebAssemblyTableType()) {
4803	Diag(OpLoc, diag::err_wasm_table_invalid_uett_operand)
4804	<< getTraitSpelling(ExprKind);
4805	return true;
4806	}
4807
4808	if (CheckObjCTraitOperandConstraints(S&: *this, T: ExprType, Loc: OpLoc, ArgRange: ExprRange,
4809	TraitKind: ExprKind))
4810	return true;
4811
4812	if (ExprType->isVariablyModifiedType() && FunctionScopes.size() > 1) {
4813	if (auto *TT = ExprType->getAs<TypedefType>()) {
4814	for (auto I = FunctionScopes.rbegin(),
4815	E = std::prev(x: FunctionScopes.rend());
4816	I != E; ++I) {
4817	auto *CSI = dyn_cast<CapturingScopeInfo>(Val: *I);
4818	if (CSI == nullptr)
4819	break;
4820	DeclContext *DC = nullptr;
4821	if (auto *LSI = dyn_cast<LambdaScopeInfo>(Val: CSI))
4822	DC = LSI->CallOperator;
4823	else if (auto *CRSI = dyn_cast<CapturedRegionScopeInfo>(Val: CSI))
4824	DC = CRSI->TheCapturedDecl;
4825	else if (auto *BSI = dyn_cast<BlockScopeInfo>(Val: CSI))
4826	DC = BSI->TheDecl;
4827	if (DC) {
4828	if (DC->containsDecl(TT->getDecl()))
4829	break;
4830	captureVariablyModifiedType(Context, T: ExprType, CSI);
4831	}
4832	}
4833	}
4834	}
4835
4836	return false;
4837	}
4838
4839	/// Build a sizeof or alignof expression given a type operand.
4840	ExprResult Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo,
4841	SourceLocation OpLoc,
4842	UnaryExprOrTypeTrait ExprKind,
4843	SourceRange R) {
4844	if (!TInfo)
4845	return ExprError();
4846
4847	QualType T = TInfo->getType();
4848
4849	if (!T->isDependentType() &&
4850	CheckUnaryExprOrTypeTraitOperand(ExprType: T, OpLoc, ExprRange: R, ExprKind,
4851	KWName: getTraitSpelling(T: ExprKind)))
4852	return ExprError();
4853
4854	// Adds overload of TransformToPotentiallyEvaluated for TypeSourceInfo to
4855	// properly deal with VLAs in nested calls of sizeof and typeof.
4856	if (isUnevaluatedContext() && ExprKind == UETT_SizeOf &&
4857	TInfo->getType()->isVariablyModifiedType())
4858	TInfo = TransformToPotentiallyEvaluated(TInfo);
4859
4860	// C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
4861	return new (Context) UnaryExprOrTypeTraitExpr(
4862	ExprKind, TInfo, Context.getSizeType(), OpLoc, R.getEnd());
4863	}
4864
4865	/// Build a sizeof or alignof expression given an expression
4866	/// operand.
4867	ExprResult
4868	Sema::CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc,
4869	UnaryExprOrTypeTrait ExprKind) {
4870	ExprResult PE = CheckPlaceholderExpr(E);
4871	if (PE.isInvalid())
4872	return ExprError();
4873
4874	E = PE.get();
4875
4876	// Verify that the operand is valid.
4877	bool isInvalid = false;
4878	if (E->isTypeDependent()) {
4879	// Delay type-checking for type-dependent expressions.
4880	} else if (ExprKind == UETT_AlignOf || ExprKind == UETT_PreferredAlignOf) {
4881	isInvalid = CheckAlignOfExpr(S&: *this, E, ExprKind);
4882	} else if (ExprKind == UETT_VecStep) {
4883	isInvalid = CheckVecStepExpr(E);
4884	} else if (ExprKind == UETT_OpenMPRequiredSimdAlign) {
4885	Diag(E->getExprLoc(), diag::err_openmp_default_simd_align_expr);
4886	isInvalid = true;
4887	} else if (E->refersToBitField()) { // C99 6.5.3.4p1.
4888	Diag(E->getExprLoc(), diag::err_sizeof_alignof_typeof_bitfield) << 0;
4889	isInvalid = true;
4890	} else if (ExprKind == UETT_VectorElements) {
4891	isInvalid = CheckUnaryExprOrTypeTraitOperand(E, ExprKind: UETT_VectorElements);
4892	} else {
4893	isInvalid = CheckUnaryExprOrTypeTraitOperand(E, ExprKind: UETT_SizeOf);
4894	}
4895
4896	if (isInvalid)
4897	return ExprError();
4898
4899	if (ExprKind == UETT_SizeOf && E->getType()->isVariableArrayType()) {
4900	PE = TransformToPotentiallyEvaluated(E);
4901	if (PE.isInvalid()) return ExprError();
4902	E = PE.get();
4903	}
4904
4905	// C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
4906	return new (Context) UnaryExprOrTypeTraitExpr(
4907	ExprKind, E, Context.getSizeType(), OpLoc, E->getSourceRange().getEnd());
4908	}
4909
4910	/// ActOnUnaryExprOrTypeTraitExpr - Handle @c sizeof(type) and @c sizeof @c
4911	/// expr and the same for @c alignof and @c __alignof
4912	/// Note that the ArgRange is invalid if isType is false.
4913	ExprResult
4914	Sema::ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc,
4915	UnaryExprOrTypeTrait ExprKind, bool IsType,
4916	void *TyOrEx, SourceRange ArgRange) {
4917	// If error parsing type, ignore.
4918	if (!TyOrEx) return ExprError();
4919
4920	if (IsType) {
4921	TypeSourceInfo *TInfo;
4922	(void) GetTypeFromParser(Ty: ParsedType::getFromOpaquePtr(P: TyOrEx), TInfo: &TInfo);
4923	return CreateUnaryExprOrTypeTraitExpr(TInfo, OpLoc, ExprKind, R: ArgRange);
4924	}
4925
4926	Expr *ArgEx = (Expr *)TyOrEx;
4927	ExprResult Result = CreateUnaryExprOrTypeTraitExpr(E: ArgEx, OpLoc, ExprKind);
4928	return Result;
4929	}
4930
4931	bool Sema::CheckAlignasTypeArgument(StringRef KWName, TypeSourceInfo *TInfo,
4932	SourceLocation OpLoc, SourceRange R) {
4933	if (!TInfo)
4934	return true;
4935	return CheckUnaryExprOrTypeTraitOperand(ExprType: TInfo->getType(), OpLoc, ExprRange: R,
4936	ExprKind: UETT_AlignOf, KWName);
4937	}
4938
4939	/// ActOnAlignasTypeArgument - Handle @c alignas(type-id) and @c
4940	/// _Alignas(type-name) .
4941	/// [dcl.align] An alignment-specifier of the form
4942	/// alignas(type-id) has the same effect as alignas(alignof(type-id)).
4943	///
4944	/// [N1570 6.7.5] _Alignas(type-name) is equivalent to
4945	/// _Alignas(_Alignof(type-name)).
4946	bool Sema::ActOnAlignasTypeArgument(StringRef KWName, ParsedType Ty,
4947	SourceLocation OpLoc, SourceRange R) {
4948	TypeSourceInfo *TInfo;
4949	(void)GetTypeFromParser(Ty: ParsedType::getFromOpaquePtr(P: Ty.getAsOpaquePtr()),
4950	TInfo: &TInfo);
4951	return CheckAlignasTypeArgument(KWName, TInfo, OpLoc, R);
4952	}
4953
4954	static QualType CheckRealImagOperand(Sema &S, ExprResult &V, SourceLocation Loc,
4955	bool IsReal) {
4956	if (V.get()->isTypeDependent())
4957	return S.Context.DependentTy;
4958
4959	// _Real and _Imag are only l-values for normal l-values.
4960	if (V.get()->getObjectKind() != OK_Ordinary) {
4961	V = S.DefaultLvalueConversion(E: V.get());
4962	if (V.isInvalid())
4963	return QualType();
4964	}
4965
4966	// These operators return the element type of a complex type.
4967	if (const ComplexType *CT = V.get()->getType()->getAs<ComplexType>())
4968	return CT->getElementType();
4969
4970	// Otherwise they pass through real integer and floating point types here.
4971	if (V.get()->getType()->isArithmeticType())
4972	return V.get()->getType();
4973
4974	// Test for placeholders.
4975	ExprResult PR = S.CheckPlaceholderExpr(E: V.get());
4976	if (PR.isInvalid()) return QualType();
4977	if (PR.get() != V.get()) {
4978	V = PR;
4979	return CheckRealImagOperand(S, V, Loc, IsReal);
4980	}
4981
4982	// Reject anything else.
4983	S.Diag(Loc, diag::err_realimag_invalid_type) << V.get()->getType()
4984	<< (IsReal ? "__real" : "__imag");
4985	return QualType();
4986	}
4987
4988
4989
4990	ExprResult
4991	Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc,
4992	tok::TokenKind Kind, Expr *Input) {
4993	UnaryOperatorKind Opc;
4994	switch (Kind) {
4995	default: llvm_unreachable("Unknown unary op!");
4996	case tok::plusplus: Opc = UO_PostInc; break;
4997	case tok::minusminus: Opc = UO_PostDec; break;
4998	}
4999
5000	// Since this might is a postfix expression, get rid of ParenListExprs.
5001	ExprResult Result = MaybeConvertParenListExprToParenExpr(S, ME: Input);
5002	if (Result.isInvalid()) return ExprError();
5003	Input = Result.get();
5004
5005	return BuildUnaryOp(S, OpLoc, Opc, Input);
5006	}
5007
5008	/// Diagnose if arithmetic on the given ObjC pointer is illegal.
5009	///
5010	/// \return true on error
5011	static bool checkArithmeticOnObjCPointer(Sema &S,
5012	SourceLocation opLoc,
5013	Expr *op) {
5014	assert(op->getType()->isObjCObjectPointerType());
5015	if (S.LangOpts.ObjCRuntime.allowsPointerArithmetic() &&
5016	!S.LangOpts.ObjCSubscriptingLegacyRuntime)
5017	return false;
5018
5019	S.Diag(opLoc, diag::err_arithmetic_nonfragile_interface)
5020	<< op->getType()->castAs<ObjCObjectPointerType>()->getPointeeType()
5021	<< op->getSourceRange();
5022	return true;
5023	}
5024
5025	static bool isMSPropertySubscriptExpr(Sema &S, Expr *Base) {
5026	auto *BaseNoParens = Base->IgnoreParens();
5027	if (auto *MSProp = dyn_cast<MSPropertyRefExpr>(Val: BaseNoParens))
5028	return MSProp->getPropertyDecl()->getType()->isArrayType();
5029	return isa<MSPropertySubscriptExpr>(Val: BaseNoParens);
5030	}
5031
5032	// Returns the type used for LHS[RHS], given one of LHS, RHS is type-dependent.
5033	// Typically this is DependentTy, but can sometimes be more precise.
5034	//
5035	// There are cases when we could determine a non-dependent type:
5036	// - LHS and RHS may have non-dependent types despite being type-dependent
5037	// (e.g. unbounded array static members of the current instantiation)
5038	// - one may be a dependent-sized array with known element type
5039	// - one may be a dependent-typed valid index (enum in current instantiation)
5040	//
5041	// We *always* return a dependent type, in such cases it is DependentTy.
5042	// This avoids creating type-dependent expressions with non-dependent types.
5043	// FIXME: is this important to avoid? See https://reviews.llvm.org/D107275
5044	static QualType getDependentArraySubscriptType(Expr *LHS, Expr *RHS,
5045	const ASTContext &Ctx) {
5046	assert(LHS->isTypeDependent() || RHS->isTypeDependent());
5047	QualType LTy = LHS->getType(), RTy = RHS->getType();
5048	QualType Result = Ctx.DependentTy;
5049	if (RTy->isIntegralOrUnscopedEnumerationType()) {
5050	if (const PointerType *PT = LTy->getAs<PointerType>())
5051	Result = PT->getPointeeType();
5052	else if (const ArrayType *AT = LTy->getAsArrayTypeUnsafe())
5053	Result = AT->getElementType();
5054	} else if (LTy->isIntegralOrUnscopedEnumerationType()) {
5055	if (const PointerType *PT = RTy->getAs<PointerType>())
5056	Result = PT->getPointeeType();
5057	else if (const ArrayType *AT = RTy->getAsArrayTypeUnsafe())
5058	Result = AT->getElementType();
5059	}
5060	// Ensure we return a dependent type.
5061	return Result->isDependentType() ? Result : Ctx.DependentTy;
5062	}
5063
5064	ExprResult Sema::ActOnArraySubscriptExpr(Scope *S, Expr *base,
5065	SourceLocation lbLoc,
5066	MultiExprArg ArgExprs,
5067	SourceLocation rbLoc) {
5068
5069	if (base && !base->getType().isNull() &&
5070	base->hasPlaceholderType(K: BuiltinType::OMPArraySection))
5071	return ActOnOMPArraySectionExpr(Base: base, LBLoc: lbLoc, LowerBound: ArgExprs.front(), ColonLocFirst: SourceLocation(),
5072	ColonLocSecond: SourceLocation(), /*Length*/ nullptr,
5073	/*Stride=*/nullptr, RBLoc: rbLoc);
5074
5075	// Since this might be a postfix expression, get rid of ParenListExprs.
5076	if (isa<ParenListExpr>(Val: base)) {
5077	ExprResult result = MaybeConvertParenListExprToParenExpr(S, ME: base);
5078	if (result.isInvalid())
5079	return ExprError();
5080	base = result.get();
5081	}
5082
5083	// Check if base and idx form a MatrixSubscriptExpr.
5084	//
5085	// Helper to check for comma expressions, which are not allowed as indices for
5086	// matrix subscript expressions.
5087	auto CheckAndReportCommaError = [this, base, rbLoc](Expr *E) {
5088	if (isa<BinaryOperator>(Val: E) && cast<BinaryOperator>(Val: E)->isCommaOp()) {
5089	Diag(E->getExprLoc(), diag::err_matrix_subscript_comma)
5090	<< SourceRange(base->getBeginLoc(), rbLoc);
5091	return true;
5092	}
5093	return false;
5094	};
5095	// The matrix subscript operator ([][])is considered a single operator.
5096	// Separating the index expressions by parenthesis is not allowed.
5097	if (base && !base->getType().isNull() &&
5098	base->hasPlaceholderType(K: BuiltinType::IncompleteMatrixIdx) &&
5099	!isa<MatrixSubscriptExpr>(Val: base)) {
5100	Diag(base->getExprLoc(), diag::err_matrix_separate_incomplete_index)
5101	<< SourceRange(base->getBeginLoc(), rbLoc);
5102	return ExprError();
5103	}
5104	// If the base is a MatrixSubscriptExpr, try to create a new
5105	// MatrixSubscriptExpr.
5106	auto *matSubscriptE = dyn_cast<MatrixSubscriptExpr>(Val: base);
5107	if (matSubscriptE) {
5108	assert(ArgExprs.size() == 1);
5109	if (CheckAndReportCommaError(ArgExprs.front()))
5110	return ExprError();
5111
5112	assert(matSubscriptE->isIncomplete() &&
5113	"base has to be an incomplete matrix subscript");
5114	return CreateBuiltinMatrixSubscriptExpr(Base: matSubscriptE->getBase(),
5115	RowIdx: matSubscriptE->getRowIdx(),
5116	ColumnIdx: ArgExprs.front(), RBLoc: rbLoc);
5117	}
5118	if (base->getType()->isWebAssemblyTableType()) {
5119	Diag(base->getExprLoc(), diag::err_wasm_table_art)
5120	<< SourceRange(base->getBeginLoc(), rbLoc) << 3;
5121	return ExprError();
5122	}
5123
5124	// Handle any non-overload placeholder types in the base and index
5125	// expressions. We can't handle overloads here because the other
5126	// operand might be an overloadable type, in which case the overload
5127	// resolution for the operator overload should get the first crack
5128	// at the overload.
5129	bool IsMSPropertySubscript = false;
5130	if (base->getType()->isNonOverloadPlaceholderType()) {
5131	IsMSPropertySubscript = isMSPropertySubscriptExpr(S&: *this, Base: base);
5132	if (!IsMSPropertySubscript) {
5133	ExprResult result = CheckPlaceholderExpr(E: base);
5134	if (result.isInvalid())
5135	return ExprError();
5136	base = result.get();
5137	}
5138	}
5139
5140	// If the base is a matrix type, try to create a new MatrixSubscriptExpr.
5141	if (base->getType()->isMatrixType()) {
5142	assert(ArgExprs.size() == 1);
5143	if (CheckAndReportCommaError(ArgExprs.front()))
5144	return ExprError();
5145
5146	return CreateBuiltinMatrixSubscriptExpr(Base: base, RowIdx: ArgExprs.front(), ColumnIdx: nullptr,
5147	RBLoc: rbLoc);
5148	}
5149
5150	if (ArgExprs.size() == 1 && getLangOpts().CPlusPlus20) {
5151	Expr *idx = ArgExprs[0];
5152	if ((isa<BinaryOperator>(Val: idx) && cast<BinaryOperator>(Val: idx)->isCommaOp()) ||
5153	(isa<CXXOperatorCallExpr>(Val: idx) &&
5154	cast<CXXOperatorCallExpr>(Val: idx)->getOperator() == OO_Comma)) {
5155	Diag(idx->getExprLoc(), diag::warn_deprecated_comma_subscript)
5156	<< SourceRange(base->getBeginLoc(), rbLoc);
5157	}
5158	}
5159
5160	if (ArgExprs.size() == 1 &&
5161	ArgExprs[0]->getType()->isNonOverloadPlaceholderType()) {
5162	ExprResult result = CheckPlaceholderExpr(E: ArgExprs[0]);
5163	if (result.isInvalid())
5164	return ExprError();
5165	ArgExprs[0] = result.get();
5166	} else {
5167	if (CheckArgsForPlaceholders(args: ArgExprs))
5168	return ExprError();
5169	}
5170
5171	// Build an unanalyzed expression if either operand is type-dependent.
5172	if (getLangOpts().CPlusPlus && ArgExprs.size() == 1 &&
5173	(base->isTypeDependent() ||
5174	Expr::hasAnyTypeDependentArguments(Exprs: ArgExprs)) &&
5175	!isa<PackExpansionExpr>(Val: ArgExprs[0])) {
5176	return new (Context) ArraySubscriptExpr(
5177	base, ArgExprs.front(),
5178	getDependentArraySubscriptType(LHS: base, RHS: ArgExprs.front(), Ctx: getASTContext()),
5179	VK_LValue, OK_Ordinary, rbLoc);
5180	}
5181
5182	// MSDN, property (C++)
5183	// https://msdn.microsoft.com/en-us/library/yhfk0thd(v=vs.120).aspx
5184	// This attribute can also be used in the declaration of an empty array in a
5185	// class or structure definition. For example:
5186	// __declspec(property(get=GetX, put=PutX)) int x[];
5187	// The above statement indicates that x[] can be used with one or more array
5188	// indices. In this case, i=p->x[a][b] will be turned into i=p->GetX(a, b),
5189	// and p->x[a][b] = i will be turned into p->PutX(a, b, i);
5190	if (IsMSPropertySubscript) {
5191	assert(ArgExprs.size() == 1);
5192	// Build MS property subscript expression if base is MS property reference
5193	// or MS property subscript.
5194	return new (Context)
5195	MSPropertySubscriptExpr(base, ArgExprs.front(), Context.PseudoObjectTy,
5196	VK_LValue, OK_Ordinary, rbLoc);
5197	}
5198
5199	// Use C++ overloaded-operator rules if either operand has record
5200	// type. The spec says to do this if either type is *overloadable*,
5201	// but enum types can't declare subscript operators or conversion
5202	// operators, so there's nothing interesting for overload resolution
5203	// to do if there aren't any record types involved.
5204	//
5205	// ObjC pointers have their own subscripting logic that is not tied
5206	// to overload resolution and so should not take this path.
5207	if (getLangOpts().CPlusPlus && !base->getType()->isObjCObjectPointerType() &&
5208	((base->getType()->isRecordType() ||
5209	(ArgExprs.size() != 1 || isa<PackExpansionExpr>(Val: ArgExprs[0]) ||
5210	ArgExprs[0]->getType()->isRecordType())))) {
5211	return CreateOverloadedArraySubscriptExpr(LLoc: lbLoc, RLoc: rbLoc, Base: base, Args: ArgExprs);
5212	}
5213
5214	ExprResult Res =
5215	CreateBuiltinArraySubscriptExpr(Base: base, LLoc: lbLoc, Idx: ArgExprs.front(), RLoc: rbLoc);
5216
5217	if (!Res.isInvalid() && isa<ArraySubscriptExpr>(Val: Res.get()))
5218	CheckSubscriptAccessOfNoDeref(E: cast<ArraySubscriptExpr>(Val: Res.get()));
5219
5220	return Res;
5221	}
5222
5223	ExprResult Sema::tryConvertExprToType(Expr *E, QualType Ty) {
5224	InitializedEntity Entity = InitializedEntity::InitializeTemporary(Type: Ty);
5225	InitializationKind Kind =
5226	InitializationKind::CreateCopy(InitLoc: E->getBeginLoc(), EqualLoc: SourceLocation());
5227	InitializationSequence InitSeq(*this, Entity, Kind, E);
5228	return InitSeq.Perform(S&: *this, Entity, Kind, Args: E);
5229	}
5230
5231	ExprResult Sema::CreateBuiltinMatrixSubscriptExpr(Expr *Base, Expr *RowIdx,
5232	Expr *ColumnIdx,
5233	SourceLocation RBLoc) {
5234	ExprResult BaseR = CheckPlaceholderExpr(E: Base);
5235	if (BaseR.isInvalid())
5236	return BaseR;
5237	Base = BaseR.get();
5238
5239	ExprResult RowR = CheckPlaceholderExpr(E: RowIdx);
5240	if (RowR.isInvalid())
5241	return RowR;
5242	RowIdx = RowR.get();
5243
5244	if (!ColumnIdx)
5245	return new (Context) MatrixSubscriptExpr(
5246	Base, RowIdx, ColumnIdx, Context.IncompleteMatrixIdxTy, RBLoc);
5247
5248	// Build an unanalyzed expression if any of the operands is type-dependent.
5249	if (Base->isTypeDependent() || RowIdx->isTypeDependent() ||
5250	ColumnIdx->isTypeDependent())
5251	return new (Context) MatrixSubscriptExpr(Base, RowIdx, ColumnIdx,
5252	Context.DependentTy, RBLoc);
5253
5254	ExprResult ColumnR = CheckPlaceholderExpr(E: ColumnIdx);
5255	if (ColumnR.isInvalid())
5256	return ColumnR;
5257	ColumnIdx = ColumnR.get();
5258
5259	// Check that IndexExpr is an integer expression. If it is a constant
5260	// expression, check that it is less than Dim (= the number of elements in the
5261	// corresponding dimension).
5262	auto IsIndexValid = [&](Expr *IndexExpr, unsigned Dim,
5263	bool IsColumnIdx) -> Expr * {
5264	if (!IndexExpr->getType()->isIntegerType() &&
5265	!IndexExpr->isTypeDependent()) {
5266	Diag(IndexExpr->getBeginLoc(), diag::err_matrix_index_not_integer)
5267	<< IsColumnIdx;
5268	return nullptr;
5269	}
5270
5271	if (std::optional<llvm::APSInt> Idx =
5272	IndexExpr->getIntegerConstantExpr(Ctx: Context)) {
5273	if ((*Idx < 0 || *Idx >= Dim)) {
5274	Diag(IndexExpr->getBeginLoc(), diag::err_matrix_index_outside_range)
5275	<< IsColumnIdx << Dim;
5276	return nullptr;
5277	}
5278	}
5279
5280	ExprResult ConvExpr =
5281	tryConvertExprToType(E: IndexExpr, Ty: Context.getSizeType());
5282	assert(!ConvExpr.isInvalid() &&
5283	"should be able to convert any integer type to size type");
5284	return ConvExpr.get();
5285	};
5286
5287	auto *MTy = Base->getType()->getAs<ConstantMatrixType>();
5288	RowIdx = IsIndexValid(RowIdx, MTy->getNumRows(), false);
5289	ColumnIdx = IsIndexValid(ColumnIdx, MTy->getNumColumns(), true);
5290	if (!RowIdx || !ColumnIdx)
5291	return ExprError();
5292
5293	return new (Context) MatrixSubscriptExpr(Base, RowIdx, ColumnIdx,
5294	MTy->getElementType(), RBLoc);
5295	}
5296
5297	void Sema::CheckAddressOfNoDeref(const Expr *E) {
5298	ExpressionEvaluationContextRecord &LastRecord = ExprEvalContexts.back();
5299	const Expr *StrippedExpr = E->IgnoreParenImpCasts();
5300
5301	// For expressions like `&(*s).b`, the base is recorded and what should be
5302	// checked.
5303	const MemberExpr *Member = nullptr;
5304	while ((Member = dyn_cast<MemberExpr>(Val: StrippedExpr)) && !Member->isArrow())
5305	StrippedExpr = Member->getBase()->IgnoreParenImpCasts();
5306
5307	LastRecord.PossibleDerefs.erase(Ptr: StrippedExpr);
5308	}
5309
5310	void Sema::CheckSubscriptAccessOfNoDeref(const ArraySubscriptExpr *E) {
5311	if (isUnevaluatedContext())
5312	return;
5313
5314	QualType ResultTy = E->getType();
5315	ExpressionEvaluationContextRecord &LastRecord = ExprEvalContexts.back();
5316
5317	// Bail if the element is an array since it is not memory access.
5318	if (isa<ArrayType>(Val: ResultTy))
5319	return;
5320
5321	if (ResultTy->hasAttr(attr::NoDeref)) {
5322	LastRecord.PossibleDerefs.insert(E);
5323	return;
5324	}
5325
5326	// Check if the base type is a pointer to a member access of a struct
5327	// marked with noderef.
5328	const Expr *Base = E->getBase();
5329	QualType BaseTy = Base->getType();
5330	if (!(isa<ArrayType>(Val: BaseTy) || isa<PointerType>(Val: BaseTy)))
5331	// Not a pointer access
5332	return;
5333
5334	const MemberExpr *Member = nullptr;
5335	while ((Member = dyn_cast<MemberExpr>(Val: Base->IgnoreParenCasts())) &&
5336	Member->isArrow())
5337	Base = Member->getBase();
5338
5339	if (const auto *Ptr = dyn_cast<PointerType>(Val: Base->getType())) {
5340	if (Ptr->getPointeeType()->hasAttr(attr::NoDeref))
5341	LastRecord.PossibleDerefs.insert(E);
5342	}
5343	}
5344
5345	ExprResult Sema::ActOnOMPArraySectionExpr(Expr *Base, SourceLocation LBLoc,
5346	Expr *LowerBound,
5347	SourceLocation ColonLocFirst,
5348	SourceLocation ColonLocSecond,
5349	Expr *Length, Expr *Stride,
5350	SourceLocation RBLoc) {
5351	if (Base->hasPlaceholderType() &&
5352	!Base->hasPlaceholderType(K: BuiltinType::OMPArraySection)) {
5353	ExprResult Result = CheckPlaceholderExpr(E: Base);
5354	if (Result.isInvalid())
5355	return ExprError();
5356	Base = Result.get();
5357	}
5358	if (LowerBound && LowerBound->getType()->isNonOverloadPlaceholderType()) {
5359	ExprResult Result = CheckPlaceholderExpr(E: LowerBound);
5360	if (Result.isInvalid())
5361	return ExprError();
5362	Result = DefaultLvalueConversion(E: Result.get());
5363	if (Result.isInvalid())
5364	return ExprError();
5365	LowerBound = Result.get();
5366	}
5367	if (Length && Length->getType()->isNonOverloadPlaceholderType()) {
5368	ExprResult Result = CheckPlaceholderExpr(E: Length);
5369	if (Result.isInvalid())
5370	return ExprError();
5371	Result = DefaultLvalueConversion(E: Result.get());
5372	if (Result.isInvalid())
5373	return ExprError();
5374	Length = Result.get();
5375	}
5376	if (Stride && Stride->getType()->isNonOverloadPlaceholderType()) {
5377	ExprResult Result = CheckPlaceholderExpr(E: Stride);
5378	if (Result.isInvalid())
5379	return ExprError();
5380	Result = DefaultLvalueConversion(E: Result.get());
5381	if (Result.isInvalid())
5382	return ExprError();
5383	Stride = Result.get();
5384	}
5385
5386	// Build an unanalyzed expression if either operand is type-dependent.
5387	if (Base->isTypeDependent() ||
5388	(LowerBound &&
5389	(LowerBound->isTypeDependent() || LowerBound->isValueDependent())) ||
5390	(Length && (Length->isTypeDependent() || Length->isValueDependent())) ||
5391	(Stride && (Stride->isTypeDependent() || Stride->isValueDependent()))) {
5392	return new (Context) OMPArraySectionExpr(
5393	Base, LowerBound, Length, Stride, Context.DependentTy, VK_LValue,
5394	OK_Ordinary, ColonLocFirst, ColonLocSecond, RBLoc);
5395	}
5396
5397	// Perform default conversions.
5398	QualType OriginalTy = OMPArraySectionExpr::getBaseOriginalType(Base);
5399	QualType ResultTy;
5400	if (OriginalTy->isAnyPointerType()) {
5401	ResultTy = OriginalTy->getPointeeType();
5402	} else if (OriginalTy->isArrayType()) {
5403	ResultTy = OriginalTy->getAsArrayTypeUnsafe()->getElementType();
5404	} else {
5405	return ExprError(
5406	Diag(Base->getExprLoc(), diag::err_omp_typecheck_section_value)
5407	<< Base->getSourceRange());
5408	}
5409	// C99 6.5.2.1p1
5410	if (LowerBound) {
5411	auto Res = PerformOpenMPImplicitIntegerConversion(OpLoc: LowerBound->getExprLoc(),
5412	Op: LowerBound);
5413	if (Res.isInvalid())
5414	return ExprError(Diag(LowerBound->getExprLoc(),
5415	diag::err_omp_typecheck_section_not_integer)
5416	<< 0 << LowerBound->getSourceRange());
5417	LowerBound = Res.get();
5418
5419	if (LowerBound->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
5420	LowerBound->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
5421	Diag(LowerBound->getExprLoc(), diag::warn_omp_section_is_char)
5422	<< 0 << LowerBound->getSourceRange();
5423	}
5424	if (Length) {
5425	auto Res =
5426	PerformOpenMPImplicitIntegerConversion(OpLoc: Length->getExprLoc(), Op: Length);
5427	if (Res.isInvalid())
5428	return ExprError(Diag(Length->getExprLoc(),
5429	diag::err_omp_typecheck_section_not_integer)
5430	<< 1 << Length->getSourceRange());
5431	Length = Res.get();
5432
5433	if (Length->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
5434	Length->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
5435	Diag(Length->getExprLoc(), diag::warn_omp_section_is_char)
5436	<< 1 << Length->getSourceRange();
5437	}
5438	if (Stride) {
5439	ExprResult Res =
5440	PerformOpenMPImplicitIntegerConversion(OpLoc: Stride->getExprLoc(), Op: Stride);
5441	if (Res.isInvalid())
5442	return ExprError(Diag(Stride->getExprLoc(),
5443	diag::err_omp_typecheck_section_not_integer)
5444	<< 1 << Stride->getSourceRange());
5445	Stride = Res.get();
5446
5447	if (Stride->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
5448	Stride->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
5449	Diag(Stride->getExprLoc(), diag::warn_omp_section_is_char)
5450	<< 1 << Stride->getSourceRange();
5451	}
5452
5453	// C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly,
5454	// C++ [expr.sub]p1: The type "T" shall be a completely-defined object
5455	// type. Note that functions are not objects, and that (in C99 parlance)
5456	// incomplete types are not object types.
5457	if (ResultTy->isFunctionType()) {
5458	Diag(Base->getExprLoc(), diag::err_omp_section_function_type)
5459	<< ResultTy << Base->getSourceRange();
5460	return ExprError();
5461	}
5462
5463	if (RequireCompleteType(Base->getExprLoc(), ResultTy,
5464	diag::err_omp_section_incomplete_type, Base))
5465	return ExprError();
5466
5467	if (LowerBound && !OriginalTy->isAnyPointerType()) {
5468	Expr::EvalResult Result;
5469	if (LowerBound->EvaluateAsInt(Result, Ctx: Context)) {
5470	// OpenMP 5.0, [2.1.5 Array Sections]
5471	// The array section must be a subset of the original array.
5472	llvm::APSInt LowerBoundValue = Result.Val.getInt();
5473	if (LowerBoundValue.isNegative()) {
5474	Diag(LowerBound->getExprLoc(), diag::err_omp_section_not_subset_of_array)
5475	<< LowerBound->getSourceRange();
5476	return ExprError();
5477	}
5478	}
5479	}
5480
5481	if (Length) {
5482	Expr::EvalResult Result;
5483	if (Length->EvaluateAsInt(Result, Ctx: Context)) {
5484	// OpenMP 5.0, [2.1.5 Array Sections]
5485	// The length must evaluate to non-negative integers.
5486	llvm::APSInt LengthValue = Result.Val.getInt();
5487	if (LengthValue.isNegative()) {
5488	Diag(Length->getExprLoc(), diag::err_omp_section_length_negative)
5489	<< toString(LengthValue, /*Radix=*/10, /*Signed=*/true)
5490	<< Length->getSourceRange();
5491	return ExprError();
5492	}
5493	}
5494	} else if (ColonLocFirst.isValid() &&
5495	(OriginalTy.isNull() || (!OriginalTy->isConstantArrayType() &&
5496	!OriginalTy->isVariableArrayType()))) {
5497	// OpenMP 5.0, [2.1.5 Array Sections]
5498	// When the size of the array dimension is not known, the length must be
5499	// specified explicitly.
5500	Diag(ColonLocFirst, diag::err_omp_section_length_undefined)
5501	<< (!OriginalTy.isNull() && OriginalTy->isArrayType());
5502	return ExprError();
5503	}
5504
5505	if (Stride) {
5506	Expr::EvalResult Result;
5507	if (Stride->EvaluateAsInt(Result, Ctx: Context)) {
5508	// OpenMP 5.0, [2.1.5 Array Sections]
5509	// The stride must evaluate to a positive integer.
5510	llvm::APSInt StrideValue = Result.Val.getInt();
5511	if (!StrideValue.isStrictlyPositive()) {
5512	Diag(Stride->getExprLoc(), diag::err_omp_section_stride_non_positive)
5513	<< toString(StrideValue, /*Radix=*/10, /*Signed=*/true)
5514	<< Stride->getSourceRange();
5515	return ExprError();
5516	}
5517	}
5518	}
5519
5520	if (!Base->hasPlaceholderType(K: BuiltinType::OMPArraySection)) {
5521	ExprResult Result = DefaultFunctionArrayLvalueConversion(E: Base);
5522	if (Result.isInvalid())
5523	return ExprError();
5524	Base = Result.get();
5525	}
5526	return new (Context) OMPArraySectionExpr(
5527	Base, LowerBound, Length, Stride, Context.OMPArraySectionTy, VK_LValue,
5528	OK_Ordinary, ColonLocFirst, ColonLocSecond, RBLoc);
5529	}
5530
5531	ExprResult Sema::ActOnOMPArrayShapingExpr(Expr *Base, SourceLocation LParenLoc,
5532	SourceLocation RParenLoc,
5533	ArrayRef<Expr *> Dims,
5534	ArrayRef<SourceRange> Brackets) {
5535	if (Base->hasPlaceholderType()) {
5536	ExprResult Result = CheckPlaceholderExpr(E: Base);
5537	if (Result.isInvalid())
5538	return ExprError();
5539	Result = DefaultLvalueConversion(E: Result.get());
5540	if (Result.isInvalid())
5541	return ExprError();
5542	Base = Result.get();
5543	}
5544	QualType BaseTy = Base->getType();
5545	// Delay analysis of the types/expressions if instantiation/specialization is
5546	// required.
5547	if (!BaseTy->isPointerType() && Base->isTypeDependent())
5548	return OMPArrayShapingExpr::Create(Context, T: Context.DependentTy, Op: Base,
5549	L: LParenLoc, R: RParenLoc, Dims, BracketRanges: Brackets);
5550	if (!BaseTy->isPointerType() ||
5551	(!Base->isTypeDependent() &&
5552	BaseTy->getPointeeType()->isIncompleteType()))
5553	return ExprError(Diag(Base->getExprLoc(),
5554	diag::err_omp_non_pointer_type_array_shaping_base)
5555	<< Base->getSourceRange());
5556
5557	SmallVector<Expr *, 4> NewDims;
5558	bool ErrorFound = false;
5559	for (Expr *Dim : Dims) {
5560	if (Dim->hasPlaceholderType()) {
5561	ExprResult Result = CheckPlaceholderExpr(E: Dim);
5562	if (Result.isInvalid()) {
5563	ErrorFound = true;
5564	continue;
5565	}
5566	Result = DefaultLvalueConversion(E: Result.get());
5567	if (Result.isInvalid()) {
5568	ErrorFound = true;
5569	continue;
5570	}
5571	Dim = Result.get();
5572	}
5573	if (!Dim->isTypeDependent()) {
5574	ExprResult Result =
5575	PerformOpenMPImplicitIntegerConversion(OpLoc: Dim->getExprLoc(), Op: Dim);
5576	if (Result.isInvalid()) {
5577	ErrorFound = true;
5578	Diag(Dim->getExprLoc(), diag::err_omp_typecheck_shaping_not_integer)
5579	<< Dim->getSourceRange();
5580	continue;
5581	}
5582	Dim = Result.get();
5583	Expr::EvalResult EvResult;
5584	if (!Dim->isValueDependent() && Dim->EvaluateAsInt(Result&: EvResult, Ctx: Context)) {
5585	// OpenMP 5.0, [2.1.4 Array Shaping]
5586	// Each si is an integral type expression that must evaluate to a
5587	// positive integer.
5588	llvm::APSInt Value = EvResult.Val.getInt();
5589	if (!Value.isStrictlyPositive()) {
5590	Diag(Dim->getExprLoc(), diag::err_omp_shaping_dimension_not_positive)
5591	<< toString(Value, /*Radix=*/10, /*Signed=*/true)
5592	<< Dim->getSourceRange();
5593	ErrorFound = true;
5594	continue;
5595	}
5596	}
5597	}
5598	NewDims.push_back(Elt: Dim);
5599	}
5600	if (ErrorFound)
5601	return ExprError();
5602	return OMPArrayShapingExpr::Create(Context, T: Context.OMPArrayShapingTy, Op: Base,
5603	L: LParenLoc, R: RParenLoc, Dims: NewDims, BracketRanges: Brackets);
5604	}
5605
5606	ExprResult Sema::ActOnOMPIteratorExpr(Scope *S, SourceLocation IteratorKwLoc,
5607	SourceLocation LLoc, SourceLocation RLoc,
5608	ArrayRef<OMPIteratorData> Data) {
5609	SmallVector<OMPIteratorExpr::IteratorDefinition, 4> ID;
5610	bool IsCorrect = true;
5611	for (const OMPIteratorData &D : Data) {
5612	TypeSourceInfo *TInfo = nullptr;
5613	SourceLocation StartLoc;
5614	QualType DeclTy;
5615	if (!D.Type.getAsOpaquePtr()) {
5616	// OpenMP 5.0, 2.1.6 Iterators
5617	// In an iterator-specifier, if the iterator-type is not specified then
5618	// the type of that iterator is of int type.
5619	DeclTy = Context.IntTy;
5620	StartLoc = D.DeclIdentLoc;
5621	} else {
5622	DeclTy = GetTypeFromParser(Ty: D.Type, TInfo: &TInfo);
5623	StartLoc = TInfo->getTypeLoc().getBeginLoc();
5624	}
5625
5626	bool IsDeclTyDependent = DeclTy->isDependentType() ||
5627	DeclTy->containsUnexpandedParameterPack() ||
5628	DeclTy->isInstantiationDependentType();
5629	if (!IsDeclTyDependent) {
5630	if (!DeclTy->isIntegralType(Ctx: Context) && !DeclTy->isAnyPointerType()) {
5631	// OpenMP 5.0, 2.1.6 Iterators, Restrictions, C/C++
5632	// The iterator-type must be an integral or pointer type.
5633	Diag(StartLoc, diag::err_omp_iterator_not_integral_or_pointer)
5634	<< DeclTy;
5635	IsCorrect = false;
5636	continue;
5637	}
5638	if (DeclTy.isConstant(Ctx: Context)) {
5639	// OpenMP 5.0, 2.1.6 Iterators, Restrictions, C/C++
5640	// The iterator-type must not be const qualified.
5641	Diag(StartLoc, diag::err_omp_iterator_not_integral_or_pointer)
5642	<< DeclTy;
5643	IsCorrect = false;
5644	continue;
5645	}
5646	}
5647
5648	// Iterator declaration.
5649	assert(D.DeclIdent && "Identifier expected.");
5650	// Always try to create iterator declarator to avoid extra error messages
5651	// about unknown declarations use.
5652	auto *VD = VarDecl::Create(C&: Context, DC: CurContext, StartLoc, IdLoc: D.DeclIdentLoc,
5653	Id: D.DeclIdent, T: DeclTy, TInfo, S: SC_None);
5654	VD->setImplicit();
5655	if (S) {
5656	// Check for conflicting previous declaration.
5657	DeclarationNameInfo NameInfo(VD->getDeclName(), D.DeclIdentLoc);
5658	LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
5659	ForVisibleRedeclaration);
5660	Previous.suppressDiagnostics();
5661	LookupName(R&: Previous, S);
5662
5663	FilterLookupForScope(R&: Previous, Ctx: CurContext, S, /*ConsiderLinkage=*/false,
5664	/*AllowInlineNamespace=*/false);
5665	if (!Previous.empty()) {
5666	NamedDecl *Old = Previous.getRepresentativeDecl();
5667	Diag(D.DeclIdentLoc, diag::err_redefinition) << VD->getDeclName();
5668	Diag(Old->getLocation(), diag::note_previous_definition);
5669	} else {
5670	PushOnScopeChains(VD, S);
5671	}
5672	} else {
5673	CurContext->addDecl(VD);
5674	}
5675
5676	/// Act on the iterator variable declaration.
5677	ActOnOpenMPIteratorVarDecl(VD);
5678
5679	Expr *Begin = D.Range.Begin;
5680	if (!IsDeclTyDependent && Begin && !Begin->isTypeDependent()) {
5681	ExprResult BeginRes =
5682	PerformImplicitConversion(From: Begin, ToType: DeclTy, Action: AA_Converting);
5683	Begin = BeginRes.get();
5684	}
5685	Expr *End = D.Range.End;
5686	if (!IsDeclTyDependent && End && !End->isTypeDependent()) {
5687	ExprResult EndRes = PerformImplicitConversion(From: End, ToType: DeclTy, Action: AA_Converting);
5688	End = EndRes.get();
5689	}
5690	Expr *Step = D.Range.Step;
5691	if (!IsDeclTyDependent && Step && !Step->isTypeDependent()) {
5692	if (!Step->getType()->isIntegralType(Ctx: Context)) {
5693	Diag(Step->getExprLoc(), diag::err_omp_iterator_step_not_integral)
5694	<< Step << Step->getSourceRange();
5695	IsCorrect = false;
5696	continue;
5697	}
5698	std::optional<llvm::APSInt> Result =
5699	Step->getIntegerConstantExpr(Ctx: Context);
5700	// OpenMP 5.0, 2.1.6 Iterators, Restrictions
5701	// If the step expression of a range-specification equals zero, the
5702	// behavior is unspecified.
5703	if (Result && Result->isZero()) {
5704	Diag(Step->getExprLoc(), diag::err_omp_iterator_step_constant_zero)
5705	<< Step << Step->getSourceRange();
5706	IsCorrect = false;
5707	continue;
5708	}
5709	}
5710	if (!Begin || !End || !IsCorrect) {
5711	IsCorrect = false;
5712	continue;
5713	}
5714	OMPIteratorExpr::IteratorDefinition &IDElem = ID.emplace_back();
5715	IDElem.IteratorDecl = VD;
5716	IDElem.AssignmentLoc = D.AssignLoc;
5717	IDElem.Range.Begin = Begin;
5718	IDElem.Range.End = End;
5719	IDElem.Range.Step = Step;
5720	IDElem.ColonLoc = D.ColonLoc;
5721	IDElem.SecondColonLoc = D.SecColonLoc;
5722	}
5723	if (!IsCorrect) {
5724	// Invalidate all created iterator declarations if error is found.
5725	for (const OMPIteratorExpr::IteratorDefinition &D : ID) {
5726	if (Decl *ID = D.IteratorDecl)
5727	ID->setInvalidDecl();
5728	}
5729	return ExprError();
5730	}
5731	SmallVector<OMPIteratorHelperData, 4> Helpers;
5732	if (!CurContext->isDependentContext()) {
5733	// Build number of ityeration for each iteration range.
5734	// Ni = ((Stepi > 0) ? ((Endi + Stepi -1 - Begini)/Stepi) :
5735	// ((Begini-Stepi-1-Endi) / -Stepi);
5736	for (OMPIteratorExpr::IteratorDefinition &D : ID) {
5737	// (Endi - Begini)
5738	ExprResult Res = CreateBuiltinBinOp(OpLoc: D.AssignmentLoc, Opc: BO_Sub, LHSExpr: D.Range.End,
5739	RHSExpr: D.Range.Begin);
5740	if(!Res.isUsable()) {
5741	IsCorrect = false;
5742	continue;
5743	}
5744	ExprResult St, St1;
5745	if (D.Range.Step) {
5746	St = D.Range.Step;
5747	// (Endi - Begini) + Stepi
5748	Res = CreateBuiltinBinOp(OpLoc: D.AssignmentLoc, Opc: BO_Add, LHSExpr: Res.get(), RHSExpr: St.get());
5749	if (!Res.isUsable()) {
5750	IsCorrect = false;
5751	continue;
5752	}
5753	// (Endi - Begini) + Stepi - 1
5754	Res =
5755	CreateBuiltinBinOp(OpLoc: D.AssignmentLoc, Opc: BO_Sub, LHSExpr: Res.get(),
5756	RHSExpr: ActOnIntegerConstant(Loc: D.AssignmentLoc, Val: 1).get());
5757	if (!Res.isUsable()) {
5758	IsCorrect = false;
5759	continue;
5760	}
5761	// ((Endi - Begini) + Stepi - 1) / Stepi
5762	Res = CreateBuiltinBinOp(OpLoc: D.AssignmentLoc, Opc: BO_Div, LHSExpr: Res.get(), RHSExpr: St.get());
5763	if (!Res.isUsable()) {
5764	IsCorrect = false;
5765	continue;
5766	}
5767	St1 = CreateBuiltinUnaryOp(OpLoc: D.AssignmentLoc, Opc: UO_Minus, InputExpr: D.Range.Step);
5768	// (Begini - Endi)
5769	ExprResult Res1 = CreateBuiltinBinOp(OpLoc: D.AssignmentLoc, Opc: BO_Sub,
5770	LHSExpr: D.Range.Begin, RHSExpr: D.Range.End);
5771	if (!Res1.isUsable()) {
5772	IsCorrect = false;
5773	continue;
5774	}
5775	// (Begini - Endi) - Stepi
5776	Res1 =
5777	CreateBuiltinBinOp(OpLoc: D.AssignmentLoc, Opc: BO_Add, LHSExpr: Res1.get(), RHSExpr: St1.get());
5778	if (!Res1.isUsable()) {
5779	IsCorrect = false;
5780	continue;
5781	}
5782	// (Begini - Endi) - Stepi - 1
5783	Res1 =
5784	CreateBuiltinBinOp(OpLoc: D.AssignmentLoc, Opc: BO_Sub, LHSExpr: Res1.get(),
5785	RHSExpr: ActOnIntegerConstant(Loc: D.AssignmentLoc, Val: 1).get());
5786	if (!Res1.isUsable()) {
5787	IsCorrect = false;
5788	continue;
5789	}
5790	// ((Begini - Endi) - Stepi - 1) / (-Stepi)
5791	Res1 =
5792	CreateBuiltinBinOp(OpLoc: D.AssignmentLoc, Opc: BO_Div, LHSExpr: Res1.get(), RHSExpr: St1.get());
5793	if (!Res1.isUsable()) {
5794	IsCorrect = false;
5795	continue;
5796	}
5797	// Stepi > 0.
5798	ExprResult CmpRes =
5799	CreateBuiltinBinOp(OpLoc: D.AssignmentLoc, Opc: BO_GT, LHSExpr: D.Range.Step,
5800	RHSExpr: ActOnIntegerConstant(Loc: D.AssignmentLoc, Val: 0).get());
5801	if (!CmpRes.isUsable()) {
5802	IsCorrect = false;
5803	continue;
5804	}
5805	Res = ActOnConditionalOp(QuestionLoc: D.AssignmentLoc, ColonLoc: D.AssignmentLoc, CondExpr: CmpRes.get(),
5806	LHSExpr: Res.get(), RHSExpr: Res1.get());
5807	if (!Res.isUsable()) {
5808	IsCorrect = false;
5809	continue;
5810	}
5811	}
5812	Res = ActOnFinishFullExpr(Expr: Res.get(), /*DiscardedValue=*/false);
5813	if (!Res.isUsable()) {
5814	IsCorrect = false;
5815	continue;
5816	}
5817
5818	// Build counter update.
5819	// Build counter.
5820	auto *CounterVD =
5821	VarDecl::Create(C&: Context, DC: CurContext, StartLoc: D.IteratorDecl->getBeginLoc(),
5822	IdLoc: D.IteratorDecl->getBeginLoc(), Id: nullptr,
5823	T: Res.get()->getType(), TInfo: nullptr, S: SC_None);
5824	CounterVD->setImplicit();
5825	ExprResult RefRes =
5826	BuildDeclRefExpr(CounterVD, CounterVD->getType(), VK_LValue,
5827	D.IteratorDecl->getBeginLoc());
5828	// Build counter update.
5829	// I = Begini + counter * Stepi;
5830	ExprResult UpdateRes;
5831	if (D.Range.Step) {
5832	UpdateRes = CreateBuiltinBinOp(
5833	OpLoc: D.AssignmentLoc, Opc: BO_Mul,
5834	LHSExpr: DefaultLvalueConversion(E: RefRes.get()).get(), RHSExpr: St.get());
5835	} else {
5836	UpdateRes = DefaultLvalueConversion(E: RefRes.get());
5837	}
5838	if (!UpdateRes.isUsable()) {
5839	IsCorrect = false;
5840	continue;
5841	}
5842	UpdateRes = CreateBuiltinBinOp(OpLoc: D.AssignmentLoc, Opc: BO_Add, LHSExpr: D.Range.Begin,
5843	RHSExpr: UpdateRes.get());
5844	if (!UpdateRes.isUsable()) {
5845	IsCorrect = false;
5846	continue;
5847	}
5848	ExprResult VDRes =
5849	BuildDeclRefExpr(cast<VarDecl>(Val: D.IteratorDecl),
5850	cast<VarDecl>(Val: D.IteratorDecl)->getType(), VK_LValue,
5851	D.IteratorDecl->getBeginLoc());
5852	UpdateRes = CreateBuiltinBinOp(OpLoc: D.AssignmentLoc, Opc: BO_Assign, LHSExpr: VDRes.get(),
5853	RHSExpr: UpdateRes.get());
5854	if (!UpdateRes.isUsable()) {
5855	IsCorrect = false;
5856	continue;
5857	}
5858	UpdateRes =
5859	ActOnFinishFullExpr(Expr: UpdateRes.get(), /*DiscardedValue=*/true);
5860	if (!UpdateRes.isUsable()) {
5861	IsCorrect = false;
5862	continue;
5863	}
5864	ExprResult CounterUpdateRes =
5865	CreateBuiltinUnaryOp(OpLoc: D.AssignmentLoc, Opc: UO_PreInc, InputExpr: RefRes.get());
5866	if (!CounterUpdateRes.isUsable()) {
5867	IsCorrect = false;
5868	continue;
5869	}
5870	CounterUpdateRes =
5871	ActOnFinishFullExpr(Expr: CounterUpdateRes.get(), /*DiscardedValue=*/true);
5872	if (!CounterUpdateRes.isUsable()) {
5873	IsCorrect = false;
5874	continue;
5875	}
5876	OMPIteratorHelperData &HD = Helpers.emplace_back();
5877	HD.CounterVD = CounterVD;
5878	HD.Upper = Res.get();
5879	HD.Update = UpdateRes.get();
5880	HD.CounterUpdate = CounterUpdateRes.get();
5881	}
5882	} else {
5883	Helpers.assign(NumElts: ID.size(), Elt: {});
5884	}
5885	if (!IsCorrect) {
5886	// Invalidate all created iterator declarations if error is found.
5887	for (const OMPIteratorExpr::IteratorDefinition &D : ID) {
5888	if (Decl *ID = D.IteratorDecl)
5889	ID->setInvalidDecl();
5890	}
5891	return ExprError();
5892	}
5893	return OMPIteratorExpr::Create(Context, T: Context.OMPIteratorTy, IteratorKwLoc,
5894	L: LLoc, R: RLoc, Data: ID, Helpers);
5895	}
5896
5897	ExprResult
5898	Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc,
5899	Expr *Idx, SourceLocation RLoc) {
5900	Expr *LHSExp = Base;
5901	Expr *RHSExp = Idx;
5902
5903	ExprValueKind VK = VK_LValue;
5904	ExprObjectKind OK = OK_Ordinary;
5905
5906	// Per C++ core issue 1213, the result is an xvalue if either operand is
5907	// a non-lvalue array, and an lvalue otherwise.
5908	if (getLangOpts().CPlusPlus11) {
5909	for (auto *Op : {LHSExp, RHSExp}) {
5910	Op = Op->IgnoreImplicit();
5911	if (Op->getType()->isArrayType() && !Op->isLValue())
5912	VK = VK_XValue;
5913	}
5914	}
5915
5916	// Perform default conversions.
5917	if (!LHSExp->getType()->getAs<VectorType>()) {
5918	ExprResult Result = DefaultFunctionArrayLvalueConversion(E: LHSExp);
5919	if (Result.isInvalid())
5920	return ExprError();
5921	LHSExp = Result.get();
5922	}
5923	ExprResult Result = DefaultFunctionArrayLvalueConversion(E: RHSExp);
5924	if (Result.isInvalid())
5925	return ExprError();
5926	RHSExp = Result.get();
5927
5928	QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType();
5929
5930	// C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent
5931	// to the expression *((e1)+(e2)). This means the array "Base" may actually be
5932	// in the subscript position. As a result, we need to derive the array base
5933	// and index from the expression types.
5934	Expr *BaseExpr, *IndexExpr;
5935	QualType ResultType;
5936	if (LHSTy->isDependentType() || RHSTy->isDependentType()) {
5937	BaseExpr = LHSExp;
5938	IndexExpr = RHSExp;
5939	ResultType =
5940	getDependentArraySubscriptType(LHS: LHSExp, RHS: RHSExp, Ctx: getASTContext());
5941	} else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) {
5942	BaseExpr = LHSExp;
5943	IndexExpr = RHSExp;
5944	ResultType = PTy->getPointeeType();
5945	} else if (const ObjCObjectPointerType *PTy =
5946	LHSTy->getAs<ObjCObjectPointerType>()) {
5947	BaseExpr = LHSExp;
5948	IndexExpr = RHSExp;
5949
5950	// Use custom logic if this should be the pseudo-object subscript
5951	// expression.
5952	if (!LangOpts.isSubscriptPointerArithmetic())
5953	return BuildObjCSubscriptExpression(RB: RLoc, BaseExpr, IndexExpr, getterMethod: nullptr,
5954	setterMethod: nullptr);
5955
5956	ResultType = PTy->getPointeeType();
5957	} else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) {
5958	// Handle the uncommon case of "123[Ptr]".
5959	BaseExpr = RHSExp;
5960	IndexExpr = LHSExp;
5961	ResultType = PTy->getPointeeType();
5962	} else if (const ObjCObjectPointerType *PTy =
5963	RHSTy->getAs<ObjCObjectPointerType>()) {
5964	// Handle the uncommon case of "123[Ptr]".
5965	BaseExpr = RHSExp;
5966	IndexExpr = LHSExp;
5967	ResultType = PTy->getPointeeType();
5968	if (!LangOpts.isSubscriptPointerArithmetic()) {
5969	Diag(LLoc, diag::err_subscript_nonfragile_interface)
5970	<< ResultType << BaseExpr->getSourceRange();
5971	return ExprError();
5972	}
5973	} else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) {
5974	BaseExpr = LHSExp; // vectors: V[123]
5975	IndexExpr = RHSExp;
5976	// We apply C++ DR1213 to vector subscripting too.
5977	if (getLangOpts().CPlusPlus11 && LHSExp->isPRValue()) {
5978	ExprResult Materialized = TemporaryMaterializationConversion(E: LHSExp);
5979	if (Materialized.isInvalid())
5980	return ExprError();
5981	LHSExp = Materialized.get();
5982	}
5983	VK = LHSExp->getValueKind();
5984	if (VK != VK_PRValue)
5985	OK = OK_VectorComponent;
5986
5987	ResultType = VTy->getElementType();
5988	QualType BaseType = BaseExpr->getType();
5989	Qualifiers BaseQuals = BaseType.getQualifiers();
5990	Qualifiers MemberQuals = ResultType.getQualifiers();
5991	Qualifiers Combined = BaseQuals + MemberQuals;
5992	if (Combined != MemberQuals)
5993	ResultType = Context.getQualifiedType(T: ResultType, Qs: Combined);
5994	} else if (LHSTy->isBuiltinType() &&
5995	LHSTy->getAs<BuiltinType>()->isSveVLSBuiltinType()) {
5996	const BuiltinType *BTy = LHSTy->getAs<BuiltinType>();
5997	if (BTy->isSVEBool())
5998	return ExprError(Diag(LLoc, diag::err_subscript_svbool_t)
5999	<< LHSExp->getSourceRange() << RHSExp->getSourceRange());
6000
6001	BaseExpr = LHSExp;
6002	IndexExpr = RHSExp;
6003	if (getLangOpts().CPlusPlus11 && LHSExp->isPRValue()) {
6004	ExprResult Materialized = TemporaryMaterializationConversion(E: LHSExp);
6005	if (Materialized.isInvalid())
6006	return ExprError();
6007	LHSExp = Materialized.get();
6008	}
6009	VK = LHSExp->getValueKind();
6010	if (VK != VK_PRValue)
6011	OK = OK_VectorComponent;
6012
6013	ResultType = BTy->getSveEltType(Context);
6014
6015	QualType BaseType = BaseExpr->getType();
6016	Qualifiers BaseQuals = BaseType.getQualifiers();
6017	Qualifiers MemberQuals = ResultType.getQualifiers();
6018	Qualifiers Combined = BaseQuals + MemberQuals;
6019	if (Combined != MemberQuals)
6020	ResultType = Context.getQualifiedType(T: ResultType, Qs: Combined);
6021	} else if (LHSTy->isArrayType()) {
6022	// If we see an array that wasn't promoted by
6023	// DefaultFunctionArrayLvalueConversion, it must be an array that
6024	// wasn't promoted because of the C90 rule that doesn't
6025	// allow promoting non-lvalue arrays. Warn, then
6026	// force the promotion here.
6027	Diag(LHSExp->getBeginLoc(), diag::ext_subscript_non_lvalue)
6028	<< LHSExp->getSourceRange();
6029	LHSExp = ImpCastExprToType(E: LHSExp, Type: Context.getArrayDecayedType(T: LHSTy),
6030	CK: CK_ArrayToPointerDecay).get();
6031	LHSTy = LHSExp->getType();
6032
6033	BaseExpr = LHSExp;
6034	IndexExpr = RHSExp;
6035	ResultType = LHSTy->castAs<PointerType>()->getPointeeType();
6036	} else if (RHSTy->isArrayType()) {
6037	// Same as previous, except for 123[f().a] case
6038	Diag(RHSExp->getBeginLoc(), diag::ext_subscript_non_lvalue)
6039	<< RHSExp->getSourceRange();
6040	RHSExp = ImpCastExprToType(E: RHSExp, Type: Context.getArrayDecayedType(T: RHSTy),
6041	CK: CK_ArrayToPointerDecay).get();
6042	RHSTy = RHSExp->getType();
6043
6044	BaseExpr = RHSExp;
6045	IndexExpr = LHSExp;
6046	ResultType = RHSTy->castAs<PointerType>()->getPointeeType();
6047	} else {
6048	return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value)
6049	<< LHSExp->getSourceRange() << RHSExp->getSourceRange());
6050	}
6051	// C99 6.5.2.1p1
6052	if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent())
6053	return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer)
6054	<< IndexExpr->getSourceRange());
6055
6056	if ((IndexExpr->getType()->isSpecificBuiltinType(K: BuiltinType::Char_S) ||
6057	IndexExpr->getType()->isSpecificBuiltinType(K: BuiltinType::Char_U)) &&
6058	!IndexExpr->isTypeDependent()) {
6059	std::optional<llvm::APSInt> IntegerContantExpr =
6060	IndexExpr->getIntegerConstantExpr(Ctx: getASTContext());
6061	if (!IntegerContantExpr.has_value() ||
6062	IntegerContantExpr.value().isNegative())
6063	Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange();
6064	}
6065
6066	// C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly,
6067	// C++ [expr.sub]p1: The type "T" shall be a completely-defined object
6068	// type. Note that Functions are not objects, and that (in C99 parlance)
6069	// incomplete types are not object types.
6070	if (ResultType->isFunctionType()) {
6071	Diag(BaseExpr->getBeginLoc(), diag::err_subscript_function_type)
6072	<< ResultType << BaseExpr->getSourceRange();
6073	return ExprError();
6074	}
6075
6076	if (ResultType->isVoidType() && !getLangOpts().CPlusPlus) {
6077	// GNU extension: subscripting on pointer to void
6078	Diag(LLoc, diag::ext_gnu_subscript_void_type)
6079	<< BaseExpr->getSourceRange();
6080
6081	// C forbids expressions of unqualified void type from being l-values.
6082	// See IsCForbiddenLValueType.
6083	if (!ResultType.hasQualifiers())
6084	VK = VK_PRValue;
6085	} else if (!ResultType->isDependentType() &&
6086	!ResultType.isWebAssemblyReferenceType() &&
6087	RequireCompleteSizedType(
6088	LLoc, ResultType,
6089	diag::err_subscript_incomplete_or_sizeless_type, BaseExpr))
6090	return ExprError();
6091
6092	assert(VK == VK_PRValue || LangOpts.CPlusPlus ||
6093	!ResultType.isCForbiddenLValueType());
6094
6095	if (LHSExp->IgnoreParenImpCasts()->getType()->isVariablyModifiedType() &&
6096	FunctionScopes.size() > 1) {
6097	if (auto *TT =
6098	LHSExp->IgnoreParenImpCasts()->getType()->getAs<TypedefType>()) {
6099	for (auto I = FunctionScopes.rbegin(),
6100	E = std::prev(x: FunctionScopes.rend());
6101	I != E; ++I) {
6102	auto *CSI = dyn_cast<CapturingScopeInfo>(Val: *I);
6103	if (CSI == nullptr)
6104	break;
6105	DeclContext *DC = nullptr;
6106	if (auto *LSI = dyn_cast<LambdaScopeInfo>(Val: CSI))
6107	DC = LSI->CallOperator;
6108	else if (auto *CRSI = dyn_cast<CapturedRegionScopeInfo>(Val: CSI))
6109	DC = CRSI->TheCapturedDecl;
6110	else if (auto *BSI = dyn_cast<BlockScopeInfo>(Val: CSI))
6111	DC = BSI->TheDecl;
6112	if (DC) {
6113	if (DC->containsDecl(TT->getDecl()))
6114	break;
6115	captureVariablyModifiedType(
6116	Context, T: LHSExp->IgnoreParenImpCasts()->getType(), CSI);
6117	}
6118	}
6119	}
6120	}
6121
6122	return new (Context)
6123	ArraySubscriptExpr(LHSExp, RHSExp, ResultType, VK, OK, RLoc);
6124	}
6125
6126	bool Sema::CheckCXXDefaultArgExpr(SourceLocation CallLoc, FunctionDecl *FD,
6127	ParmVarDecl *Param, Expr *RewrittenInit,
6128	bool SkipImmediateInvocations) {
6129	if (Param->hasUnparsedDefaultArg()) {
6130	assert(!RewrittenInit && "Should not have a rewritten init expression yet");
6131	// If we've already cleared out the location for the default argument,
6132	// that means we're parsing it right now.
6133	if (!UnparsedDefaultArgLocs.count(Val: Param)) {
6134	Diag(Param->getBeginLoc(), diag::err_recursive_default_argument) << FD;
6135	Diag(CallLoc, diag::note_recursive_default_argument_used_here);
6136	Param->setInvalidDecl();
6137	return true;
6138	}
6139
6140	Diag(CallLoc, diag::err_use_of_default_argument_to_function_declared_later)
6141	<< FD << cast<CXXRecordDecl>(FD->getDeclContext());
6142	Diag(UnparsedDefaultArgLocs[Param],
6143	diag::note_default_argument_declared_here);
6144	return true;
6145	}
6146
6147	if (Param->hasUninstantiatedDefaultArg()) {
6148	assert(!RewrittenInit && "Should not have a rewitten init expression yet");
6149	if (InstantiateDefaultArgument(CallLoc, FD, Param))
6150	return true;
6151	}
6152
6153	Expr *Init = RewrittenInit ? RewrittenInit : Param->getInit();
6154	assert(Init && "default argument but no initializer?");
6155
6156	// If the default expression creates temporaries, we need to
6157	// push them to the current stack of expression temporaries so they'll
6158	// be properly destroyed.
6159	// FIXME: We should really be rebuilding the default argument with new
6160	// bound temporaries; see the comment in PR5810.
6161	// We don't need to do that with block decls, though, because
6162	// blocks in default argument expression can never capture anything.
6163	if (auto *InitWithCleanup = dyn_cast<ExprWithCleanups>(Init)) {
6164	// Set the "needs cleanups" bit regardless of whether there are
6165	// any explicit objects.
6166	Cleanup.setExprNeedsCleanups(InitWithCleanup->cleanupsHaveSideEffects());
6167	// Append all the objects to the cleanup list. Right now, this
6168	// should always be a no-op, because blocks in default argument
6169	// expressions should never be able to capture anything.
6170	assert(!InitWithCleanup->getNumObjects() &&
6171	"default argument expression has capturing blocks?");
6172	}
6173	// C++ [expr.const]p15.1:
6174	// An expression or conversion is in an immediate function context if it is
6175	// potentially evaluated and [...] its innermost enclosing non-block scope
6176	// is a function parameter scope of an immediate function.
6177	EnterExpressionEvaluationContext EvalContext(
6178	*this,
6179	FD->isImmediateFunction()
6180	? ExpressionEvaluationContext::ImmediateFunctionContext
6181	: ExpressionEvaluationContext::PotentiallyEvaluated,
6182	Param);
6183	ExprEvalContexts.back().IsCurrentlyCheckingDefaultArgumentOrInitializer =
6184	SkipImmediateInvocations;
6185	runWithSufficientStackSpace(Loc: CallLoc, Fn: [&] {
6186	MarkDeclarationsReferencedInExpr(E: Init, /*SkipLocalVariables=*/true);
6187	});
6188	return false;
6189	}
6190
6191	struct ImmediateCallVisitor : public RecursiveASTVisitor<ImmediateCallVisitor> {
6192	const ASTContext &Context;
6193	ImmediateCallVisitor(const ASTContext &Ctx) : Context(Ctx) {}
6194
6195	bool HasImmediateCalls = false;
6196	bool shouldVisitImplicitCode() const { return true; }
6197
6198	bool VisitCallExpr(CallExpr *E) {
6199	if (const FunctionDecl *FD = E->getDirectCallee())
6200	HasImmediateCalls |= FD->isImmediateFunction();
6201	return RecursiveASTVisitor<ImmediateCallVisitor>::VisitStmt(E);
6202	}
6203
6204	// SourceLocExpr are not immediate invocations
6205	// but CXXDefaultInitExpr/CXXDefaultArgExpr containing a SourceLocExpr
6206	// need to be rebuilt so that they refer to the correct SourceLocation and
6207	// DeclContext.
6208	bool VisitSourceLocExpr(SourceLocExpr *E) {
6209	HasImmediateCalls = true;
6210	return RecursiveASTVisitor<ImmediateCallVisitor>::VisitStmt(E);
6211	}
6212
6213	// A nested lambda might have parameters with immediate invocations
6214	// in their default arguments.
6215	// The compound statement is not visited (as it does not constitute a
6216	// subexpression).
6217	// FIXME: We should consider visiting and transforming captures
6218	// with init expressions.
6219	bool VisitLambdaExpr(LambdaExpr *E) {
6220	return VisitCXXMethodDecl(E->getCallOperator());
6221	}
6222
6223	// Blocks don't support default parameters, and, as for lambdas,
6224	// we don't consider their body a subexpression.
6225	bool VisitBlockDecl(BlockDecl *B) { return false; }
6226
6227	bool VisitCompoundStmt(CompoundStmt *B) { return false; }
6228
6229	bool VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
6230	return TraverseStmt(E->getExpr());
6231	}
6232
6233	bool VisitCXXDefaultInitExpr(CXXDefaultInitExpr *E) {
6234	return TraverseStmt(E->getExpr());
6235	}
6236	};
6237
6238	struct EnsureImmediateInvocationInDefaultArgs
6239	: TreeTransform<EnsureImmediateInvocationInDefaultArgs> {
6240	EnsureImmediateInvocationInDefaultArgs(Sema &SemaRef)
6241	: TreeTransform(SemaRef) {}
6242
6243	// Lambda can only have immediate invocations in the default
6244	// args of their parameters, which is transformed upon calling the closure.
6245	// The body is not a subexpression, so we have nothing to do.
6246	// FIXME: Immediate calls in capture initializers should be transformed.
6247	ExprResult TransformLambdaExpr(LambdaExpr *E) { return E; }
6248	ExprResult TransformBlockExpr(BlockExpr *E) { return E; }
6249
6250	// Make sure we don't rebuild the this pointer as it would
6251	// cause it to incorrectly point it to the outermost class
6252	// in the case of nested struct initialization.
6253	ExprResult TransformCXXThisExpr(CXXThisExpr *E) { return E; }
6254	};
6255
6256	ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc,
6257	FunctionDecl *FD, ParmVarDecl *Param,
6258	Expr *Init) {
6259	assert(Param->hasDefaultArg() && "can't build nonexistent default arg");
6260
6261	bool NestedDefaultChecking = isCheckingDefaultArgumentOrInitializer();
6262	bool InLifetimeExtendingContext = isInLifetimeExtendingContext();
6263	std::optional<ExpressionEvaluationContextRecord::InitializationContext>
6264	InitializationContext =
6265	OutermostDeclarationWithDelayedImmediateInvocations();
6266	if (!InitializationContext.has_value())
6267	InitializationContext.emplace(CallLoc, Param, CurContext);
6268
6269	if (!Init && !Param->hasUnparsedDefaultArg()) {
6270	// Mark that we are replacing a default argument first.
6271	// If we are instantiating a template we won't have to
6272	// retransform immediate calls.
6273	// C++ [expr.const]p15.1:
6274	// An expression or conversion is in an immediate function context if it
6275	// is potentially evaluated and [...] its innermost enclosing non-block
6276	// scope is a function parameter scope of an immediate function.
6277	EnterExpressionEvaluationContext EvalContext(
6278	*this,
6279	FD->isImmediateFunction()
6280	? ExpressionEvaluationContext::ImmediateFunctionContext
6281	: ExpressionEvaluationContext::PotentiallyEvaluated,
6282	Param);
6283
6284	if (Param->hasUninstantiatedDefaultArg()) {
6285	if (InstantiateDefaultArgument(CallLoc, FD, Param))
6286	return ExprError();
6287	}
6288	// CWG2631
6289	// An immediate invocation that is not evaluated where it appears is
6290	// evaluated and checked for whether it is a constant expression at the
6291	// point where the enclosing initializer is used in a function call.
6292	ImmediateCallVisitor V(getASTContext());
6293	if (!NestedDefaultChecking)
6294	V.TraverseDecl(Param);
6295
6296	// Rewrite the call argument that was created from the corresponding
6297	// parameter's default argument.
6298	if (V.HasImmediateCalls || InLifetimeExtendingContext) {
6299	if (V.HasImmediateCalls)
6300	ExprEvalContexts.back().DelayedDefaultInitializationContext = {
6301	CallLoc, Param, CurContext};
6302	// Pass down lifetime extending flag, and collect temporaries in
6303	// CreateMaterializeTemporaryExpr when we rewrite the call argument.
6304	keepInLifetimeExtendingContext();
6305	keepInMaterializeTemporaryObjectContext();
6306	EnsureImmediateInvocationInDefaultArgs Immediate(*this);
6307	ExprResult Res;
6308	runWithSufficientStackSpace(Loc: CallLoc, Fn: [&] {
6309	Res = Immediate.TransformInitializer(Param->getInit(),
6310	/*NotCopy=*/false);
6311	});
6312	if (Res.isInvalid())
6313	return ExprError();
6314	Res = ConvertParamDefaultArgument(Param, DefaultArg: Res.get(),
6315	EqualLoc: Res.get()->getBeginLoc());
6316	if (Res.isInvalid())
6317	return ExprError();
6318	Init = Res.get();
6319	}
6320	}
6321
6322	if (CheckCXXDefaultArgExpr(
6323	CallLoc, FD, Param, RewrittenInit: Init,
6324	/*SkipImmediateInvocations=*/NestedDefaultChecking))
6325	return ExprError();
6326
6327	return CXXDefaultArgExpr::Create(C: Context, Loc: InitializationContext->Loc, Param,
6328	RewrittenExpr: Init, UsedContext: InitializationContext->Context);
6329	}
6330
6331	ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
6332	assert(Field->hasInClassInitializer());
6333
6334	// If we might have already tried and failed to instantiate, don't try again.
6335	if (Field->isInvalidDecl())
6336	return ExprError();
6337
6338	CXXThisScopeRAII This(*this, Field->getParent(), Qualifiers());
6339
6340	auto *ParentRD = cast<CXXRecordDecl>(Val: Field->getParent());
6341
6342	std::optional<ExpressionEvaluationContextRecord::InitializationContext>
6343	InitializationContext =
6344	OutermostDeclarationWithDelayedImmediateInvocations();
6345	if (!InitializationContext.has_value())
6346	InitializationContext.emplace(Loc, Field, CurContext);
6347
6348	Expr *Init = nullptr;
6349
6350	bool NestedDefaultChecking = isCheckingDefaultArgumentOrInitializer();
6351
6352	EnterExpressionEvaluationContext EvalContext(
6353	*this, ExpressionEvaluationContext::PotentiallyEvaluated, Field);
6354
6355	if (!Field->getInClassInitializer()) {
6356	// Maybe we haven't instantiated the in-class initializer. Go check the
6357	// pattern FieldDecl to see if it has one.
6358	if (isTemplateInstantiation(Kind: ParentRD->getTemplateSpecializationKind())) {
6359	CXXRecordDecl *ClassPattern = ParentRD->getTemplateInstantiationPattern();
6360	DeclContext::lookup_result Lookup =
6361	ClassPattern->lookup(Name: Field->getDeclName());
6362
6363	FieldDecl *Pattern = nullptr;
6364	for (auto *L : Lookup) {
6365	if ((Pattern = dyn_cast<FieldDecl>(L)))
6366	break;
6367	}
6368	assert(Pattern && "We must have set the Pattern!");
6369	if (!Pattern->hasInClassInitializer() ||
6370	InstantiateInClassInitializer(PointOfInstantiation: Loc, Instantiation: Field, Pattern,
6371	TemplateArgs: getTemplateInstantiationArgs(Field))) {
6372	Field->setInvalidDecl();
6373	return ExprError();
6374	}
6375	}
6376	}
6377
6378	// CWG2631
6379	// An immediate invocation that is not evaluated where it appears is
6380	// evaluated and checked for whether it is a constant expression at the
6381	// point where the enclosing initializer is used in a [...] a constructor
6382	// definition, or an aggregate initialization.
6383	ImmediateCallVisitor V(getASTContext());
6384	if (!NestedDefaultChecking)
6385	V.TraverseDecl(Field);
6386	if (V.HasImmediateCalls) {
6387	ExprEvalContexts.back().DelayedDefaultInitializationContext = {Loc, Field,
6388	CurContext};
6389	ExprEvalContexts.back().IsCurrentlyCheckingDefaultArgumentOrInitializer =
6390	NestedDefaultChecking;
6391
6392	EnsureImmediateInvocationInDefaultArgs Immediate(*this);
6393	ExprResult Res;
6394	runWithSufficientStackSpace(Loc, Fn: [&] {
6395	Res = Immediate.TransformInitializer(Field->getInClassInitializer(),
6396	/*CXXDirectInit=*/false);
6397	});
6398	if (!Res.isInvalid())
6399	Res = ConvertMemberDefaultInitExpression(FD: Field, InitExpr: Res.get(), InitLoc: Loc);
6400	if (Res.isInvalid()) {
6401	Field->setInvalidDecl();
6402	return ExprError();
6403	}
6404	Init = Res.get();
6405	}
6406
6407	if (Field->getInClassInitializer()) {
6408	Expr *E = Init ? Init : Field->getInClassInitializer();
6409	if (!NestedDefaultChecking)
6410	runWithSufficientStackSpace(Loc, Fn: [&] {
6411	MarkDeclarationsReferencedInExpr(E, /*SkipLocalVariables=*/false);
6412	});
6413	// C++11 [class.base.init]p7:
6414	// The initialization of each base and member constitutes a
6415	// full-expression.
6416	ExprResult Res = ActOnFinishFullExpr(Expr: E, /*DiscardedValue=*/false);
6417	if (Res.isInvalid()) {
6418	Field->setInvalidDecl();
6419	return ExprError();
6420	}
6421	Init = Res.get();
6422
6423	return CXXDefaultInitExpr::Create(Ctx: Context, Loc: InitializationContext->Loc,
6424	Field, UsedContext: InitializationContext->Context,
6425	RewrittenInitExpr: Init);
6426	}
6427
6428	// DR1351:
6429	// If the brace-or-equal-initializer of a non-static data member
6430	// invokes a defaulted default constructor of its class or of an
6431	// enclosing class in a potentially evaluated subexpression, the
6432	// program is ill-formed.
6433	//
6434	// This resolution is unworkable: the exception specification of the
6435	// default constructor can be needed in an unevaluated context, in
6436	// particular, in the operand of a noexcept-expression, and we can be
6437	// unable to compute an exception specification for an enclosed class.
6438	//
6439	// Any attempt to resolve the exception specification of a defaulted default
6440	// constructor before the initializer is lexically complete will ultimately
6441	// come here at which point we can diagnose it.
6442	RecordDecl *OutermostClass = ParentRD->getOuterLexicalRecordContext();
6443	Diag(Loc, diag::err_default_member_initializer_not_yet_parsed)
6444	<< OutermostClass << Field;
6445	Diag(Field->getEndLoc(),
6446	diag::note_default_member_initializer_not_yet_parsed);
6447	// Recover by marking the field invalid, unless we're in a SFINAE context.
6448	if (!isSFINAEContext())
6449	Field->setInvalidDecl();
6450	return ExprError();
6451	}
6452
6453	Sema::VariadicCallType
6454	Sema::getVariadicCallType(FunctionDecl *FDecl, const FunctionProtoType *Proto,
6455	Expr *Fn) {
6456	if (Proto && Proto->isVariadic()) {
6457	if (isa_and_nonnull<CXXConstructorDecl>(Val: FDecl))
6458	return VariadicConstructor;
6459	else if (Fn && Fn->getType()->isBlockPointerType())
6460	return VariadicBlock;
6461	else if (FDecl) {
6462	if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(Val: FDecl))
6463	if (Method->isInstance())
6464	return VariadicMethod;
6465	} else if (Fn && Fn->getType() == Context.BoundMemberTy)
6466	return VariadicMethod;
6467	return VariadicFunction;
6468	}
6469	return VariadicDoesNotApply;
6470	}
6471
6472	namespace {
6473	class FunctionCallCCC final : public FunctionCallFilterCCC {
6474	public:
6475	FunctionCallCCC(Sema &SemaRef, const IdentifierInfo *FuncName,
6476	unsigned NumArgs, MemberExpr *ME)
6477	: FunctionCallFilterCCC(SemaRef, NumArgs, false, ME),
6478	FunctionName(FuncName) {}
6479
6480	bool ValidateCandidate(const TypoCorrection &candidate) override {
6481	if (!candidate.getCorrectionSpecifier() ||
6482	candidate.getCorrectionAsIdentifierInfo() != FunctionName) {
6483	return false;
6484	}
6485
6486	return FunctionCallFilterCCC::ValidateCandidate(candidate);
6487	}
6488
6489	std::unique_ptr<CorrectionCandidateCallback> clone() override {
6490	return std::make_unique<FunctionCallCCC>(args&: *this);
6491	}
6492
6493	private:
6494	const IdentifierInfo *const FunctionName;
6495	};
6496	}
6497
6498	static TypoCorrection TryTypoCorrectionForCall(Sema &S, Expr *Fn,
6499	FunctionDecl *FDecl,
6500	ArrayRef<Expr *> Args) {
6501	MemberExpr *ME = dyn_cast<MemberExpr>(Val: Fn);
6502	DeclarationName FuncName = FDecl->getDeclName();
6503	SourceLocation NameLoc = ME ? ME->getMemberLoc() : Fn->getBeginLoc();
6504
6505	FunctionCallCCC CCC(S, FuncName.getAsIdentifierInfo(), Args.size(), ME);
6506	if (TypoCorrection Corrected = S.CorrectTypo(
6507	Typo: DeclarationNameInfo(FuncName, NameLoc), LookupKind: Sema::LookupOrdinaryName,
6508	S: S.getScopeForContext(Ctx: S.CurContext), SS: nullptr, CCC,
6509	Mode: Sema::CTK_ErrorRecovery)) {
6510	if (NamedDecl *ND = Corrected.getFoundDecl()) {
6511	if (Corrected.isOverloaded()) {
6512	OverloadCandidateSet OCS(NameLoc, OverloadCandidateSet::CSK_Normal);
6513	OverloadCandidateSet::iterator Best;
6514	for (NamedDecl *CD : Corrected) {
6515	if (FunctionDecl *FD = dyn_cast<FunctionDecl>(CD))
6516	S.AddOverloadCandidate(FD, DeclAccessPair::make(FD, AS_none), Args,
6517	OCS);
6518	}
6519	switch (OCS.BestViableFunction(S, Loc: NameLoc, Best)) {
6520	case OR_Success:
6521	ND = Best->FoundDecl;
6522	Corrected.setCorrectionDecl(ND);
6523	break;
6524	default:
6525	break;
6526	}
6527	}
6528	ND = ND->getUnderlyingDecl();
6529	if (isa<ValueDecl>(Val: ND) || isa<FunctionTemplateDecl>(Val: ND))
6530	return Corrected;
6531	}
6532	}
6533	return TypoCorrection();
6534	}
6535
6536	/// ConvertArgumentsForCall - Converts the arguments specified in
6537	/// Args/NumArgs to the parameter types of the function FDecl with
6538	/// function prototype Proto. Call is the call expression itself, and
6539	/// Fn is the function expression. For a C++ member function, this
6540	/// routine does not attempt to convert the object argument. Returns
6541	/// true if the call is ill-formed.
6542	bool
6543	Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn,
6544	FunctionDecl *FDecl,
6545	const FunctionProtoType *Proto,
6546	ArrayRef<Expr *> Args,
6547	SourceLocation RParenLoc,
6548	bool IsExecConfig) {
6549	// Bail out early if calling a builtin with custom typechecking.
6550	if (FDecl)
6551	if (unsigned ID = FDecl->getBuiltinID())
6552	if (Context.BuiltinInfo.hasCustomTypechecking(ID))
6553	return false;
6554
6555	// C99 6.5.2.2p7 - the arguments are implicitly converted, as if by
6556	// assignment, to the types of the corresponding parameter, ...
6557	bool HasExplicitObjectParameter =
6558	FDecl && FDecl->hasCXXExplicitFunctionObjectParameter();
6559	unsigned ExplicitObjectParameterOffset = HasExplicitObjectParameter ? 1 : 0;
6560	unsigned NumParams = Proto->getNumParams();
6561	bool Invalid = false;
6562	unsigned MinArgs = FDecl ? FDecl->getMinRequiredArguments() : NumParams;
6563	unsigned FnKind = Fn->getType()->isBlockPointerType()
6564	? 1 /* block */
6565	: (IsExecConfig ? 3 /* kernel function (exec config) */
6566	: 0 /* function */);
6567
6568	// If too few arguments are available (and we don't have default
6569	// arguments for the remaining parameters), don't make the call.
6570	if (Args.size() < NumParams) {
6571	if (Args.size() < MinArgs) {
6572	TypoCorrection TC;
6573	if (FDecl && (TC = TryTypoCorrectionForCall(S&: *this, Fn, FDecl, Args))) {
6574	unsigned diag_id =
6575	MinArgs == NumParams && !Proto->isVariadic()
6576	? diag::err_typecheck_call_too_few_args_suggest
6577	: diag::err_typecheck_call_too_few_args_at_least_suggest;
6578	diagnoseTypo(
6579	Correction: TC, TypoDiag: PDiag(DiagID: diag_id)
6580	<< FnKind << MinArgs - ExplicitObjectParameterOffset
6581	<< static_cast<unsigned>(Args.size()) -
6582	ExplicitObjectParameterOffset
6583	<< HasExplicitObjectParameter << TC.getCorrectionRange());
6584	} else if (MinArgs - ExplicitObjectParameterOffset == 1 && FDecl &&
6585	FDecl->getParamDecl(ExplicitObjectParameterOffset)
6586	->getDeclName())
6587	Diag(RParenLoc,
6588	MinArgs == NumParams && !Proto->isVariadic()
6589	? diag::err_typecheck_call_too_few_args_one
6590	: diag::err_typecheck_call_too_few_args_at_least_one)
6591	<< FnKind << FDecl->getParamDecl(ExplicitObjectParameterOffset)
6592	<< HasExplicitObjectParameter << Fn->getSourceRange();
6593	else
6594	Diag(RParenLoc, MinArgs == NumParams && !Proto->isVariadic()
6595	? diag::err_typecheck_call_too_few_args
6596	: diag::err_typecheck_call_too_few_args_at_least)
6597	<< FnKind << MinArgs - ExplicitObjectParameterOffset
6598	<< static_cast<unsigned>(Args.size()) -
6599	ExplicitObjectParameterOffset
6600	<< HasExplicitObjectParameter << Fn->getSourceRange();
6601
6602	// Emit the location of the prototype.
6603	if (!TC && FDecl && !FDecl->getBuiltinID() && !IsExecConfig)
6604	Diag(FDecl->getLocation(), diag::note_callee_decl)
6605	<< FDecl << FDecl->getParametersSourceRange();
6606
6607	return true;
6608	}
6609	// We reserve space for the default arguments when we create
6610	// the call expression, before calling ConvertArgumentsForCall.
6611	assert((Call->getNumArgs() == NumParams) &&
6612	"We should have reserved space for the default arguments before!");
6613	}
6614
6615	// If too many are passed and not variadic, error on the extras and drop
6616	// them.
6617	if (Args.size() > NumParams) {
6618	if (!Proto->isVariadic()) {
6619	TypoCorrection TC;
6620	if (FDecl && (TC = TryTypoCorrectionForCall(S&: *this, Fn, FDecl, Args))) {
6621	unsigned diag_id =
6622	MinArgs == NumParams && !Proto->isVariadic()
6623	? diag::err_typecheck_call_too_many_args_suggest
6624	: diag::err_typecheck_call_too_many_args_at_most_suggest;
6625	diagnoseTypo(
6626	Correction: TC, TypoDiag: PDiag(DiagID: diag_id)
6627	<< FnKind << NumParams - ExplicitObjectParameterOffset
6628	<< static_cast<unsigned>(Args.size()) -
6629	ExplicitObjectParameterOffset
6630	<< HasExplicitObjectParameter << TC.getCorrectionRange());
6631	} else if (NumParams - ExplicitObjectParameterOffset == 1 && FDecl &&
6632	FDecl->getParamDecl(ExplicitObjectParameterOffset)
6633	->getDeclName())
6634	Diag(Args[NumParams]->getBeginLoc(),
6635	MinArgs == NumParams
6636	? diag::err_typecheck_call_too_many_args_one
6637	: diag::err_typecheck_call_too_many_args_at_most_one)
6638	<< FnKind << FDecl->getParamDecl(ExplicitObjectParameterOffset)
6639	<< static_cast<unsigned>(Args.size()) -
6640	ExplicitObjectParameterOffset
6641	<< HasExplicitObjectParameter << Fn->getSourceRange()
6642	<< SourceRange(Args[NumParams]->getBeginLoc(),
6643	Args.back()->getEndLoc());
6644	else
6645	Diag(Args[NumParams]->getBeginLoc(),
6646	MinArgs == NumParams
6647	? diag::err_typecheck_call_too_many_args
6648	: diag::err_typecheck_call_too_many_args_at_most)
6649	<< FnKind << NumParams - ExplicitObjectParameterOffset
6650	<< static_cast<unsigned>(Args.size()) -
6651	ExplicitObjectParameterOffset
6652	<< HasExplicitObjectParameter << Fn->getSourceRange()
6653	<< SourceRange(Args[NumParams]->getBeginLoc(),
6654	Args.back()->getEndLoc());
6655
6656	// Emit the location of the prototype.
6657	if (!TC && FDecl && !FDecl->getBuiltinID() && !IsExecConfig)
6658	Diag(FDecl->getLocation(), diag::note_callee_decl)
6659	<< FDecl << FDecl->getParametersSourceRange();
6660
6661	// This deletes the extra arguments.
6662	Call->shrinkNumArgs(NewNumArgs: NumParams);
6663	return true;
6664	}
6665	}
6666	SmallVector<Expr *, 8> AllArgs;
6667	VariadicCallType CallType = getVariadicCallType(FDecl, Proto, Fn);
6668
6669	Invalid = GatherArgumentsForCall(CallLoc: Call->getBeginLoc(), FDecl, Proto, FirstParam: 0, Args,
6670	AllArgs, CallType);
6671	if (Invalid)
6672	return true;
6673	unsigned TotalNumArgs = AllArgs.size();
6674	for (unsigned i = 0; i < TotalNumArgs; ++i)
6675	Call->setArg(Arg: i, ArgExpr: AllArgs[i]);
6676
6677	Call->computeDependence();
6678	return false;
6679	}
6680
6681	bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, FunctionDecl *FDecl,
6682	const FunctionProtoType *Proto,
6683	unsigned FirstParam, ArrayRef<Expr *> Args,
6684	SmallVectorImpl<Expr *> &AllArgs,
6685	VariadicCallType CallType, bool AllowExplicit,
6686	bool IsListInitialization) {
6687	unsigned NumParams = Proto->getNumParams();
6688	bool Invalid = false;
6689	size_t ArgIx = 0;
6690	// Continue to check argument types (even if we have too few/many args).
6691	for (unsigned i = FirstParam; i < NumParams; i++) {
6692	QualType ProtoArgType = Proto->getParamType(i);
6693
6694	Expr *Arg;
6695	ParmVarDecl *Param = FDecl ? FDecl->getParamDecl(i) : nullptr;
6696	if (ArgIx < Args.size()) {
6697	Arg = Args[ArgIx++];
6698
6699	if (RequireCompleteType(Arg->getBeginLoc(), ProtoArgType,
6700	diag::err_call_incomplete_argument, Arg))
6701	return true;
6702
6703	// Strip the unbridged-cast placeholder expression off, if applicable.
6704	bool CFAudited = false;
6705	if (Arg->getType() == Context.ARCUnbridgedCastTy &&
6706	FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() &&
6707	(!Param || !Param->hasAttr<CFConsumedAttr>()))
6708	Arg = stripARCUnbridgedCast(e: Arg);
6709	else if (getLangOpts().ObjCAutoRefCount &&
6710	FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() &&
6711	(!Param || !Param->hasAttr<CFConsumedAttr>()))
6712	CFAudited = true;
6713
6714	if (Proto->getExtParameterInfo(I: i).isNoEscape() &&
6715	ProtoArgType->isBlockPointerType())
6716	if (auto *BE = dyn_cast<BlockExpr>(Val: Arg->IgnoreParenNoopCasts(Ctx: Context)))
6717	BE->getBlockDecl()->setDoesNotEscape();
6718
6719	InitializedEntity Entity =
6720	Param ? InitializedEntity::InitializeParameter(Context, Parm: Param,
6721	Type: ProtoArgType)
6722	: InitializedEntity::InitializeParameter(
6723	Context, Type: ProtoArgType, Consumed: Proto->isParamConsumed(I: i));
6724
6725	// Remember that parameter belongs to a CF audited API.
6726	if (CFAudited)
6727	Entity.setParameterCFAudited();
6728
6729	ExprResult ArgE = PerformCopyInitialization(
6730	Entity, EqualLoc: SourceLocation(), Init: Arg, TopLevelOfInitList: IsListInitialization, AllowExplicit);
6731	if (ArgE.isInvalid())
6732	return true;
6733
6734	Arg = ArgE.getAs<Expr>();
6735	} else {
6736	assert(Param && "can't use default arguments without a known callee");
6737
6738	ExprResult ArgExpr = BuildCXXDefaultArgExpr(CallLoc, FD: FDecl, Param);
6739	if (ArgExpr.isInvalid())
6740	return true;
6741
6742	Arg = ArgExpr.getAs<Expr>();
6743	}
6744
6745	// Check for array bounds violations for each argument to the call. This
6746	// check only triggers warnings when the argument isn't a more complex Expr
6747	// with its own checking, such as a BinaryOperator.
6748	CheckArrayAccess(E: Arg);
6749
6750	// Check for violations of C99 static array rules (C99 6.7.5.3p7).
6751	CheckStaticArrayArgument(CallLoc, Param, ArgExpr: Arg);
6752
6753	AllArgs.push_back(Elt: Arg);
6754	}
6755
6756	// If this is a variadic call, handle args passed through "...".
6757	if (CallType != VariadicDoesNotApply) {
6758	// Assume that extern "C" functions with variadic arguments that
6759	// return __unknown_anytype aren't *really* variadic.
6760	if (Proto->getReturnType() == Context.UnknownAnyTy && FDecl &&
6761	FDecl->isExternC()) {
6762	for (Expr *A : Args.slice(N: ArgIx)) {
6763	QualType paramType; // ignored
6764	ExprResult arg = checkUnknownAnyArg(callLoc: CallLoc, result: A, paramType);
6765	Invalid |= arg.isInvalid();
6766	AllArgs.push_back(Elt: arg.get());
6767	}
6768
6769	// Otherwise do argument promotion, (C99 6.5.2.2p7).
6770	} else {
6771	for (Expr *A : Args.slice(N: ArgIx)) {
6772	ExprResult Arg = DefaultVariadicArgumentPromotion(E: A, CT: CallType, FDecl);
6773	Invalid |= Arg.isInvalid();
6774	AllArgs.push_back(Elt: Arg.get());
6775	}
6776	}
6777
6778	// Check for array bounds violations.
6779	for (Expr *A : Args.slice(N: ArgIx))
6780	CheckArrayAccess(E: A);
6781	}
6782	return Invalid;
6783	}
6784
6785	static void DiagnoseCalleeStaticArrayParam(Sema &S, ParmVarDecl *PVD) {
6786	TypeLoc TL = PVD->getTypeSourceInfo()->getTypeLoc();
6787	if (DecayedTypeLoc DTL = TL.getAs<DecayedTypeLoc>())
6788	TL = DTL.getOriginalLoc();
6789	if (ArrayTypeLoc ATL = TL.getAs<ArrayTypeLoc>())
6790	S.Diag(PVD->getLocation(), diag::note_callee_static_array)
6791	<< ATL.getLocalSourceRange();
6792	}
6793
6794	/// CheckStaticArrayArgument - If the given argument corresponds to a static
6795	/// array parameter, check that it is non-null, and that if it is formed by
6796	/// array-to-pointer decay, the underlying array is sufficiently large.
6797	///
6798	/// C99 6.7.5.3p7: If the keyword static also appears within the [ and ] of the
6799	/// array type derivation, then for each call to the function, the value of the
6800	/// corresponding actual argument shall provide access to the first element of
6801	/// an array with at least as many elements as specified by the size expression.
6802	void
6803	Sema::CheckStaticArrayArgument(SourceLocation CallLoc,
6804	ParmVarDecl *Param,
6805	const Expr *ArgExpr) {
6806	// Static array parameters are not supported in C++.
6807	if (!Param || getLangOpts().CPlusPlus)
6808	return;
6809
6810	QualType OrigTy = Param->getOriginalType();
6811
6812	const ArrayType *AT = Context.getAsArrayType(T: OrigTy);
6813	if (!AT || AT->getSizeModifier() != ArraySizeModifier::Static)
6814	return;
6815
6816	if (ArgExpr->isNullPointerConstant(Ctx&: Context,
6817	NPC: Expr::NPC_NeverValueDependent)) {
6818	Diag(CallLoc, diag::warn_null_arg) << ArgExpr->getSourceRange();
6819	DiagnoseCalleeStaticArrayParam(S&: *this, PVD: Param);
6820	return;
6821	}
6822
6823	const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(Val: AT);
6824	if (!CAT)
6825	return;
6826
6827	const ConstantArrayType *ArgCAT =
6828	Context.getAsConstantArrayType(T: ArgExpr->IgnoreParenCasts()->getType());
6829	if (!ArgCAT)
6830	return;
6831
6832	if (getASTContext().hasSameUnqualifiedType(T1: CAT->getElementType(),
6833	T2: ArgCAT->getElementType())) {
6834	if (ArgCAT->getSize().ult(RHS: CAT->getSize())) {
6835	Diag(CallLoc, diag::warn_static_array_too_small)
6836	<< ArgExpr->getSourceRange()
6837	<< (unsigned)ArgCAT->getSize().getZExtValue()
6838	<< (unsigned)CAT->getSize().getZExtValue() << 0;
6839	DiagnoseCalleeStaticArrayParam(S&: *this, PVD: Param);
6840	}
6841	return;
6842	}
6843
6844	std::optional<CharUnits> ArgSize =
6845	getASTContext().getTypeSizeInCharsIfKnown(ArgCAT);
6846	std::optional<CharUnits> ParmSize =
6847	getASTContext().getTypeSizeInCharsIfKnown(CAT);
6848	if (ArgSize && ParmSize && *ArgSize < *ParmSize) {
6849	Diag(CallLoc, diag::warn_static_array_too_small)
6850	<< ArgExpr->getSourceRange() << (unsigned)ArgSize->getQuantity()
6851	<< (unsigned)ParmSize->getQuantity() << 1;
6852	DiagnoseCalleeStaticArrayParam(S&: *this, PVD: Param);
6853	}
6854	}
6855
6856	/// Given a function expression of unknown-any type, try to rebuild it
6857	/// to have a function type.
6858	static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn);
6859
6860	/// Is the given type a placeholder that we need to lower out
6861	/// immediately during argument processing?
6862	static bool isPlaceholderToRemoveAsArg(QualType type) {
6863	// Placeholders are never sugared.
6864	const BuiltinType *placeholder = dyn_cast<BuiltinType>(Val&: type);
6865	if (!placeholder) return false;
6866
6867	switch (placeholder->getKind()) {
6868	// Ignore all the non-placeholder types.
6869	#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
6870	case BuiltinType::Id:
6871	#include "clang/Basic/OpenCLImageTypes.def"
6872	#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
6873	case BuiltinType::Id:
6874	#include "clang/Basic/OpenCLExtensionTypes.def"
6875	// In practice we'll never use this, since all SVE types are sugared
6876	// via TypedefTypes rather than exposed directly as BuiltinTypes.
6877	#define SVE_TYPE(Name, Id, SingletonId) \
6878	case BuiltinType::Id:
6879	#include "clang/Basic/AArch64SVEACLETypes.def"
6880	#define PPC_VECTOR_TYPE(Name, Id, Size) \
6881	case BuiltinType::Id:
6882	#include "clang/Basic/PPCTypes.def"
6883	#define RVV_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
6884	#include "clang/Basic/RISCVVTypes.def"
6885	#define WASM_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
6886	#include "clang/Basic/WebAssemblyReferenceTypes.def"
6887	#define PLACEHOLDER_TYPE(ID, SINGLETON_ID)
6888	#define BUILTIN_TYPE(ID, SINGLETON_ID) case BuiltinType::ID:
6889	#include "clang/AST/BuiltinTypes.def"
6890	return false;
6891
6892	// We cannot lower out overload sets; they might validly be resolved
6893	// by the call machinery.
6894	case BuiltinType::Overload:
6895	return false;
6896
6897	// Unbridged casts in ARC can be handled in some call positions and
6898	// should be left in place.
6899	case BuiltinType::ARCUnbridgedCast:
6900	return false;
6901
6902	// Pseudo-objects should be converted as soon as possible.
6903	case BuiltinType::PseudoObject:
6904	return true;
6905
6906	// The debugger mode could theoretically but currently does not try
6907	// to resolve unknown-typed arguments based on known parameter types.
6908	case BuiltinType::UnknownAny:
6909	return true;
6910
6911	// These are always invalid as call arguments and should be reported.
6912	case BuiltinType::BoundMember:
6913	case BuiltinType::BuiltinFn:
6914	case BuiltinType::IncompleteMatrixIdx:
6915	case BuiltinType::OMPArraySection:
6916	case BuiltinType::OMPArrayShaping:
6917	case BuiltinType::OMPIterator:
6918	return true;
6919
6920	}
6921	llvm_unreachable("bad builtin type kind");
6922	}
6923
6924	bool Sema::CheckArgsForPlaceholders(MultiExprArg args) {
6925	// Apply this processing to all the arguments at once instead of
6926	// dying at the first failure.
6927	bool hasInvalid = false;
6928	for (size_t i = 0, e = args.size(); i != e; i++) {
6929	if (isPlaceholderToRemoveAsArg(type: args[i]->getType())) {
6930	ExprResult result = CheckPlaceholderExpr(E: args[i]);
6931	if (result.isInvalid()) hasInvalid = true;
6932	else args[i] = result.get();
6933	}
6934	}
6935	return hasInvalid;
6936	}
6937
6938	/// If a builtin function has a pointer argument with no explicit address
6939	/// space, then it should be able to accept a pointer to any address
6940	/// space as input. In order to do this, we need to replace the
6941	/// standard builtin declaration with one that uses the same address space
6942	/// as the call.
6943	///
6944	/// \returns nullptr If this builtin is not a candidate for a rewrite i.e.
6945	/// it does not contain any pointer arguments without
6946	/// an address space qualifer. Otherwise the rewritten
6947	/// FunctionDecl is returned.
6948	/// TODO: Handle pointer return types.
6949	static FunctionDecl *rewriteBuiltinFunctionDecl(Sema *Sema, ASTContext &Context,
6950	FunctionDecl *FDecl,
6951	MultiExprArg ArgExprs) {
6952
6953	QualType DeclType = FDecl->getType();
6954	const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(Val&: DeclType);
6955
6956	if (!Context.BuiltinInfo.hasPtrArgsOrResult(ID: FDecl->getBuiltinID()) || !FT ||
6957	ArgExprs.size() < FT->getNumParams())
6958	return nullptr;
6959
6960	bool NeedsNewDecl = false;
6961	unsigned i = 0;
6962	SmallVector<QualType, 8> OverloadParams;
6963
6964	for (QualType ParamType : FT->param_types()) {
6965
6966	// Convert array arguments to pointer to simplify type lookup.
6967	ExprResult ArgRes =
6968	Sema->DefaultFunctionArrayLvalueConversion(ArgExprs[i++]);
6969	if (ArgRes.isInvalid())
6970	return nullptr;
6971	Expr *Arg = ArgRes.get();
6972	QualType ArgType = Arg->getType();
6973	if (!ParamType->isPointerType() || ParamType.hasAddressSpace() ||
6974	!ArgType->isPointerType() ||
6975	!ArgType->getPointeeType().hasAddressSpace() ||
6976	isPtrSizeAddressSpace(ArgType->getPointeeType().getAddressSpace())) {
6977	OverloadParams.push_back(ParamType);
6978	continue;
6979	}
6980
6981	QualType PointeeType = ParamType->getPointeeType();
6982	if (PointeeType.hasAddressSpace())
6983	continue;
6984
6985	NeedsNewDecl = true;
6986	LangAS AS = ArgType->getPointeeType().getAddressSpace();
6987
6988	PointeeType = Context.getAddrSpaceQualType(PointeeType, AS);
6989	OverloadParams.push_back(Context.getPointerType(PointeeType));
6990	}
6991
6992	if (!NeedsNewDecl)
6993	return nullptr;
6994
6995	FunctionProtoType::ExtProtoInfo EPI;
6996	EPI.Variadic = FT->isVariadic();
6997	QualType OverloadTy = Context.getFunctionType(ResultTy: FT->getReturnType(),
6998	Args: OverloadParams, EPI);
6999	DeclContext *Parent = FDecl->getParent();
7000	FunctionDecl *OverloadDecl = FunctionDecl::Create(
7001	Context, Parent, FDecl->getLocation(), FDecl->getLocation(),
7002	FDecl->getIdentifier(), OverloadTy,
7003	/*TInfo=*/nullptr, SC_Extern, Sema->getCurFPFeatures().isFPConstrained(),
7004	false,
7005	/*hasPrototype=*/true);
7006	SmallVector<ParmVarDecl*, 16> Params;
7007	FT = cast<FunctionProtoType>(Val&: OverloadTy);
7008	for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
7009	QualType ParamType = FT->getParamType(i);
7010	ParmVarDecl *Parm =
7011	ParmVarDecl::Create(Context, OverloadDecl, SourceLocation(),
7012	SourceLocation(), nullptr, ParamType,
7013	/*TInfo=*/nullptr, SC_None, nullptr);
7014	Parm->setScopeInfo(scopeDepth: 0, parameterIndex: i);
7015	Params.push_back(Elt: Parm);
7016	}
7017	OverloadDecl->setParams(Params);
7018	Sema->mergeDeclAttributes(OverloadDecl, FDecl);
7019	return OverloadDecl;
7020	}
7021
7022	static void checkDirectCallValidity(Sema &S, const Expr *Fn,
7023	FunctionDecl *Callee,
7024	MultiExprArg ArgExprs) {
7025	// `Callee` (when called with ArgExprs) may be ill-formed. enable_if (and
7026	// similar attributes) really don't like it when functions are called with an
7027	// invalid number of args.
7028	if (S.TooManyArguments(NumParams: Callee->getNumParams(), NumArgs: ArgExprs.size(),
7029	/*PartialOverloading=*/false) &&
7030	!Callee->isVariadic())
7031	return;
7032	if (Callee->getMinRequiredArguments() > ArgExprs.size())
7033	return;
7034
7035	if (const EnableIfAttr *Attr =
7036	S.CheckEnableIf(Function: Callee, CallLoc: Fn->getBeginLoc(), Args: ArgExprs, MissingImplicitThis: true)) {
7037	S.Diag(Fn->getBeginLoc(),
7038	isa<CXXMethodDecl>(Callee)
7039	? diag::err_ovl_no_viable_member_function_in_call
7040	: diag::err_ovl_no_viable_function_in_call)
7041	<< Callee << Callee->getSourceRange();
7042	S.Diag(Callee->getLocation(),
7043	diag::note_ovl_candidate_disabled_by_function_cond_attr)
7044	<< Attr->getCond()->getSourceRange() << Attr->getMessage();
7045	return;
7046	}
7047	}
7048
7049	static bool enclosingClassIsRelatedToClassInWhichMembersWereFound(
7050	const UnresolvedMemberExpr *const UME, Sema &S) {
7051
7052	const auto GetFunctionLevelDCIfCXXClass =
7053	[](Sema &S) -> const CXXRecordDecl * {
7054	const DeclContext *const DC = S.getFunctionLevelDeclContext();
7055	if (!DC || !DC->getParent())
7056	return nullptr;
7057
7058	// If the call to some member function was made from within a member
7059	// function body 'M' return return 'M's parent.
7060	if (const auto *MD = dyn_cast<CXXMethodDecl>(Val: DC))
7061	return MD->getParent()->getCanonicalDecl();
7062	// else the call was made from within a default member initializer of a
7063	// class, so return the class.
7064	if (const auto *RD = dyn_cast<CXXRecordDecl>(Val: DC))
7065	return RD->getCanonicalDecl();
7066	return nullptr;
7067	};
7068	// If our DeclContext is neither a member function nor a class (in the
7069	// case of a lambda in a default member initializer), we can't have an
7070	// enclosing 'this'.
7071
7072	const CXXRecordDecl *const CurParentClass = GetFunctionLevelDCIfCXXClass(S);
7073	if (!CurParentClass)
7074	return false;
7075
7076	// The naming class for implicit member functions call is the class in which
7077	// name lookup starts.
7078	const CXXRecordDecl *const NamingClass =
7079	UME->getNamingClass()->getCanonicalDecl();
7080	assert(NamingClass && "Must have naming class even for implicit access");
7081
7082	// If the unresolved member functions were found in a 'naming class' that is
7083	// related (either the same or derived from) to the class that contains the
7084	// member function that itself contained the implicit member access.
7085
7086	return CurParentClass == NamingClass ||
7087	CurParentClass->isDerivedFrom(Base: NamingClass);
7088	}
7089
7090	static void
7091	tryImplicitlyCaptureThisIfImplicitMemberFunctionAccessWithDependentArgs(
7092	Sema &S, const UnresolvedMemberExpr *const UME, SourceLocation CallLoc) {
7093
7094	if (!UME)
7095	return;
7096
7097	LambdaScopeInfo *const CurLSI = S.getCurLambda();
7098	// Only try and implicitly capture 'this' within a C++ Lambda if it hasn't
7099	// already been captured, or if this is an implicit member function call (if
7100	// it isn't, an attempt to capture 'this' should already have been made).
7101	if (!CurLSI || CurLSI->ImpCaptureStyle == CurLSI->ImpCap_None ||
7102	!UME->isImplicitAccess() || CurLSI->isCXXThisCaptured())
7103	return;
7104
7105	// Check if the naming class in which the unresolved members were found is
7106	// related (same as or is a base of) to the enclosing class.
7107
7108	if (!enclosingClassIsRelatedToClassInWhichMembersWereFound(UME, S))
7109	return;
7110
7111
7112	DeclContext *EnclosingFunctionCtx = S.CurContext->getParent()->getParent();
7113	// If the enclosing function is not dependent, then this lambda is
7114	// capture ready, so if we can capture this, do so.
7115	if (!EnclosingFunctionCtx->isDependentContext()) {
7116	// If the current lambda and all enclosing lambdas can capture 'this' -
7117	// then go ahead and capture 'this' (since our unresolved overload set
7118	// contains at least one non-static member function).
7119	if (!S.CheckCXXThisCapture(Loc: CallLoc, /*Explcit*/ Explicit: false, /*Diagnose*/ BuildAndDiagnose: false))
7120	S.CheckCXXThisCapture(Loc: CallLoc);
7121	} else if (S.CurContext->isDependentContext()) {
7122	// ... since this is an implicit member reference, that might potentially
7123	// involve a 'this' capture, mark 'this' for potential capture in
7124	// enclosing lambdas.
7125	if (CurLSI->ImpCaptureStyle != CurLSI->ImpCap_None)
7126	CurLSI->addPotentialThisCapture(Loc: CallLoc);
7127	}
7128	}
7129
7130	// Once a call is fully resolved, warn for unqualified calls to specific
7131	// C++ standard functions, like move and forward.
7132	static void DiagnosedUnqualifiedCallsToStdFunctions(Sema &S,
7133	const CallExpr *Call) {
7134	// We are only checking unary move and forward so exit early here.
7135	if (Call->getNumArgs() != 1)
7136	return;
7137
7138	const Expr *E = Call->getCallee()->IgnoreParenImpCasts();
7139	if (!E || isa<UnresolvedLookupExpr>(Val: E))
7140	return;
7141	const DeclRefExpr *DRE = dyn_cast_if_present<DeclRefExpr>(Val: E);
7142	if (!DRE || !DRE->getLocation().isValid())
7143	return;
7144
7145	if (DRE->getQualifier())
7146	return;
7147
7148	const FunctionDecl *FD = Call->getDirectCallee();
7149	if (!FD)
7150	return;
7151
7152	// Only warn for some functions deemed more frequent or problematic.
7153	unsigned BuiltinID = FD->getBuiltinID();
7154	if (BuiltinID != Builtin::BImove && BuiltinID != Builtin::BIforward)
7155	return;
7156
7157	S.Diag(DRE->getLocation(), diag::warn_unqualified_call_to_std_cast_function)
7158	<< FD->getQualifiedNameAsString()
7159	<< FixItHint::CreateInsertion(DRE->getLocation(), "std::");
7160	}
7161
7162	ExprResult Sema::ActOnCallExpr(Scope *Scope, Expr *Fn, SourceLocation LParenLoc,
7163	MultiExprArg ArgExprs, SourceLocation RParenLoc,
7164	Expr *ExecConfig) {
7165	ExprResult Call =
7166	BuildCallExpr(S: Scope, Fn, LParenLoc, ArgExprs, RParenLoc, ExecConfig,
7167	/*IsExecConfig=*/false, /*AllowRecovery=*/true);
7168	if (Call.isInvalid())
7169	return Call;
7170
7171	// Diagnose uses of the C++20 "ADL-only template-id call" feature in earlier
7172	// language modes.
7173	if (const auto *ULE = dyn_cast<UnresolvedLookupExpr>(Val: Fn);
7174	ULE && ULE->hasExplicitTemplateArgs() &&
7175	ULE->decls_begin() == ULE->decls_end()) {
7176	Diag(Fn->getExprLoc(), getLangOpts().CPlusPlus20
7177	? diag::warn_cxx17_compat_adl_only_template_id
7178	: diag::ext_adl_only_template_id)
7179	<< ULE->getName();
7180	}
7181
7182	if (LangOpts.OpenMP)
7183	Call = ActOnOpenMPCall(Call, Scope, LParenLoc, ArgExprs, RParenLoc,
7184	ExecConfig);
7185	if (LangOpts.CPlusPlus) {
7186	if (const auto *CE = dyn_cast<CallExpr>(Val: Call.get()))
7187	DiagnosedUnqualifiedCallsToStdFunctions(S&: *this, Call: CE);
7188	}
7189	return Call;
7190	}
7191
7192	/// BuildCallExpr - Handle a call to Fn with the specified array of arguments.
7193	/// This provides the location of the left/right parens and a list of comma
7194	/// locations.
7195	ExprResult Sema::BuildCallExpr(Scope *Scope, Expr *Fn, SourceLocation LParenLoc,
7196	MultiExprArg ArgExprs, SourceLocation RParenLoc,
7197	Expr *ExecConfig, bool IsExecConfig,
7198	bool AllowRecovery) {
7199	// Since this might be a postfix expression, get rid of ParenListExprs.
7200	ExprResult Result = MaybeConvertParenListExprToParenExpr(S: Scope, ME: Fn);
7201	if (Result.isInvalid()) return ExprError();
7202	Fn = Result.get();
7203
7204	if (CheckArgsForPlaceholders(args: ArgExprs))
7205	return ExprError();
7206
7207	if (getLangOpts().CPlusPlus) {
7208	// If this is a pseudo-destructor expression, build the call immediately.
7209	if (isa<CXXPseudoDestructorExpr>(Val: Fn)) {
7210	if (!ArgExprs.empty()) {
7211	// Pseudo-destructor calls should not have any arguments.
7212	Diag(Fn->getBeginLoc(), diag::err_pseudo_dtor_call_with_args)
7213	<< FixItHint::CreateRemoval(
7214	SourceRange(ArgExprs.front()->getBeginLoc(),
7215	ArgExprs.back()->getEndLoc()));
7216	}
7217
7218	return CallExpr::Create(Ctx: Context, Fn, /*Args=*/{}, Ty: Context.VoidTy,
7219	VK: VK_PRValue, RParenLoc, FPFeatures: CurFPFeatureOverrides());
7220	}
7221	if (Fn->getType() == Context.PseudoObjectTy) {
7222	ExprResult result = CheckPlaceholderExpr(E: Fn);
7223	if (result.isInvalid()) return ExprError();
7224	Fn = result.get();
7225	}
7226
7227	// Determine whether this is a dependent call inside a C++ template,
7228	// in which case we won't do any semantic analysis now.
7229	if (Fn->isTypeDependent() || Expr::hasAnyTypeDependentArguments(Exprs: ArgExprs)) {
7230	if (ExecConfig) {
7231	return CUDAKernelCallExpr::Create(Ctx: Context, Fn,
7232	Config: cast<CallExpr>(Val: ExecConfig), Args: ArgExprs,
7233	Ty: Context.DependentTy, VK: VK_PRValue,
7234	RP: RParenLoc, FPFeatures: CurFPFeatureOverrides());
7235	} else {
7236
7237	tryImplicitlyCaptureThisIfImplicitMemberFunctionAccessWithDependentArgs(
7238	*this, dyn_cast<UnresolvedMemberExpr>(Val: Fn->IgnoreParens()),
7239	Fn->getBeginLoc());
7240
7241	return CallExpr::Create(Ctx: Context, Fn, Args: ArgExprs, Ty: Context.DependentTy,
7242	VK: VK_PRValue, RParenLoc, FPFeatures: CurFPFeatureOverrides());
7243	}
7244	}
7245
7246	// Determine whether this is a call to an object (C++ [over.call.object]).
7247	if (Fn->getType()->isRecordType())
7248	return BuildCallToObjectOfClassType(S: Scope, Object: Fn, LParenLoc, Args: ArgExprs,
7249	RParenLoc);
7250
7251	if (Fn->getType() == Context.UnknownAnyTy) {
7252	ExprResult result = rebuildUnknownAnyFunction(S&: *this, fn: Fn);
7253	if (result.isInvalid()) return ExprError();
7254	Fn = result.get();
7255	}
7256
7257	if (Fn->getType() == Context.BoundMemberTy) {
7258	return BuildCallToMemberFunction(S: Scope, MemExpr: Fn, LParenLoc, Args: ArgExprs,
7259	RParenLoc, ExecConfig, IsExecConfig,
7260	AllowRecovery);
7261	}
7262	}
7263
7264	// Check for overloaded calls. This can happen even in C due to extensions.
7265	if (Fn->getType() == Context.OverloadTy) {
7266	OverloadExpr::FindResult find = OverloadExpr::find(E: Fn);
7267
7268	// We aren't supposed to apply this logic if there's an '&' involved.
7269	if (!find.HasFormOfMemberPointer) {
7270	if (Expr::hasAnyTypeDependentArguments(Exprs: ArgExprs))
7271	return CallExpr::Create(Ctx: Context, Fn, Args: ArgExprs, Ty: Context.DependentTy,
7272	VK: VK_PRValue, RParenLoc, FPFeatures: CurFPFeatureOverrides());
7273	OverloadExpr *ovl = find.Expression;
7274	if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Val: ovl))
7275	return BuildOverloadedCallExpr(
7276	S: Scope, Fn, ULE, LParenLoc, Args: ArgExprs, RParenLoc, ExecConfig,
7277	/*AllowTypoCorrection=*/true, CalleesAddressIsTaken: find.IsAddressOfOperand);
7278	return BuildCallToMemberFunction(S: Scope, MemExpr: Fn, LParenLoc, Args: ArgExprs,
7279	RParenLoc, ExecConfig, IsExecConfig,
7280	AllowRecovery);
7281	}
7282	}
7283
7284	// If we're directly calling a function, get the appropriate declaration.
7285	if (Fn->getType() == Context.UnknownAnyTy) {
7286	ExprResult result = rebuildUnknownAnyFunction(S&: *this, fn: Fn);
7287	if (result.isInvalid()) return ExprError();
7288	Fn = result.get();
7289	}
7290
7291	Expr *NakedFn = Fn->IgnoreParens();
7292
7293	bool CallingNDeclIndirectly = false;
7294	NamedDecl *NDecl = nullptr;
7295	if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Val: NakedFn)) {
7296	if (UnOp->getOpcode() == UO_AddrOf) {
7297	CallingNDeclIndirectly = true;
7298	NakedFn = UnOp->getSubExpr()->IgnoreParens();
7299	}
7300	}
7301
7302	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: NakedFn)) {
7303	NDecl = DRE->getDecl();
7304
7305	FunctionDecl *FDecl = dyn_cast<FunctionDecl>(Val: NDecl);
7306	if (FDecl && FDecl->getBuiltinID()) {
7307	// Rewrite the function decl for this builtin by replacing parameters
7308	// with no explicit address space with the address space of the arguments
7309	// in ArgExprs.
7310	if ((FDecl =
7311	rewriteBuiltinFunctionDecl(Sema: this, Context, FDecl, ArgExprs))) {
7312	NDecl = FDecl;
7313	Fn = DeclRefExpr::Create(
7314	Context, FDecl->getQualifierLoc(), SourceLocation(), FDecl, false,
7315	SourceLocation(), FDecl->getType(), Fn->getValueKind(), FDecl,
7316	nullptr, DRE->isNonOdrUse());
7317	}
7318	}
7319	} else if (auto *ME = dyn_cast<MemberExpr>(Val: NakedFn))
7320	NDecl = ME->getMemberDecl();
7321
7322	if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(Val: NDecl)) {
7323	if (CallingNDeclIndirectly && !checkAddressOfFunctionIsAvailable(
7324	Function: FD, /*Complain=*/true, Loc: Fn->getBeginLoc()))
7325	return ExprError();
7326
7327	checkDirectCallValidity(S&: *this, Fn, Callee: FD, ArgExprs);
7328
7329	// If this expression is a call to a builtin function in HIP device
7330	// compilation, allow a pointer-type argument to default address space to be
7331	// passed as a pointer-type parameter to a non-default address space.
7332	// If Arg is declared in the default address space and Param is declared
7333	// in a non-default address space, perform an implicit address space cast to
7334	// the parameter type.
7335	if (getLangOpts().HIP && getLangOpts().CUDAIsDevice && FD &&
7336	FD->getBuiltinID()) {
7337	for (unsigned Idx = 0; Idx < FD->param_size(); ++Idx) {
7338	ParmVarDecl *Param = FD->getParamDecl(i: Idx);
7339	if (!ArgExprs[Idx] || !Param || !Param->getType()->isPointerType() ||
7340	!ArgExprs[Idx]->getType()->isPointerType())
7341	continue;
7342
7343	auto ParamAS = Param->getType()->getPointeeType().getAddressSpace();
7344	auto ArgTy = ArgExprs[Idx]->getType();
7345	auto ArgPtTy = ArgTy->getPointeeType();
7346	auto ArgAS = ArgPtTy.getAddressSpace();
7347
7348	// Add address space cast if target address spaces are different
7349	bool NeedImplicitASC =
7350	ParamAS != LangAS::Default && // Pointer params in generic AS don't need special handling.
7351	( ArgAS == LangAS::Default || // We do allow implicit conversion from generic AS
7352	// or from specific AS which has target AS matching that of Param.
7353	getASTContext().getTargetAddressSpace(AS: ArgAS) == getASTContext().getTargetAddressSpace(AS: ParamAS));
7354	if (!NeedImplicitASC)
7355	continue;
7356
7357	// First, ensure that the Arg is an RValue.
7358	if (ArgExprs[Idx]->isGLValue()) {
7359	ArgExprs[Idx] = ImplicitCastExpr::Create(
7360	Context, T: ArgExprs[Idx]->getType(), Kind: CK_NoOp, Operand: ArgExprs[Idx],
7361	BasePath: nullptr, Cat: VK_PRValue, FPO: FPOptionsOverride());
7362	}
7363
7364	// Construct a new arg type with address space of Param
7365	Qualifiers ArgPtQuals = ArgPtTy.getQualifiers();
7366	ArgPtQuals.setAddressSpace(ParamAS);
7367	auto NewArgPtTy =
7368	Context.getQualifiedType(T: ArgPtTy.getUnqualifiedType(), Qs: ArgPtQuals);
7369	auto NewArgTy =
7370	Context.getQualifiedType(T: Context.getPointerType(T: NewArgPtTy),
7371	Qs: ArgTy.getQualifiers());
7372
7373	// Finally perform an implicit address space cast
7374	ArgExprs[Idx] = ImpCastExprToType(E: ArgExprs[Idx], Type: NewArgTy,
7375	CK: CK_AddressSpaceConversion)
7376	.get();
7377	}
7378	}
7379	}
7380
7381	if (Context.isDependenceAllowed() &&
7382	(Fn->isTypeDependent() || Expr::hasAnyTypeDependentArguments(Exprs: ArgExprs))) {
7383	assert(!getLangOpts().CPlusPlus);
7384	assert((Fn->containsErrors() ||
7385	llvm::any_of(ArgExprs,
7386	[](clang::Expr *E) { return E->containsErrors(); })) &&
7387	"should only occur in error-recovery path.");
7388	return CallExpr::Create(Ctx: Context, Fn, Args: ArgExprs, Ty: Context.DependentTy,
7389	VK: VK_PRValue, RParenLoc, FPFeatures: CurFPFeatureOverrides());
7390	}
7391	return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Arg: ArgExprs, RParenLoc,
7392	Config: ExecConfig, IsExecConfig);
7393	}
7394
7395	/// BuildBuiltinCallExpr - Create a call to a builtin function specified by Id
7396	// with the specified CallArgs
7397	Expr *Sema::BuildBuiltinCallExpr(SourceLocation Loc, Builtin::ID Id,
7398	MultiExprArg CallArgs) {
7399	StringRef Name = Context.BuiltinInfo.getName(ID: Id);
7400	LookupResult R(*this, &Context.Idents.get(Name), Loc,
7401	Sema::LookupOrdinaryName);
7402	LookupName(R, S: TUScope, /*AllowBuiltinCreation=*/true);
7403
7404	auto *BuiltInDecl = R.getAsSingle<FunctionDecl>();
7405	assert(BuiltInDecl && "failed to find builtin declaration");
7406
7407	ExprResult DeclRef =
7408	BuildDeclRefExpr(BuiltInDecl, BuiltInDecl->getType(), VK_LValue, Loc);
7409	assert(DeclRef.isUsable() && "Builtin reference cannot fail");
7410
7411	ExprResult Call =
7412	BuildCallExpr(/*Scope=*/nullptr, Fn: DeclRef.get(), LParenLoc: Loc, ArgExprs: CallArgs, RParenLoc: Loc);
7413
7414	assert(!Call.isInvalid() && "Call to builtin cannot fail!");
7415	return Call.get();
7416	}
7417
7418	/// Parse a __builtin_astype expression.
7419	///
7420	/// __builtin_astype( value, dst type )
7421	///
7422	ExprResult Sema::ActOnAsTypeExpr(Expr *E, ParsedType ParsedDestTy,
7423	SourceLocation BuiltinLoc,
7424	SourceLocation RParenLoc) {
7425	QualType DstTy = GetTypeFromParser(Ty: ParsedDestTy);
7426	return BuildAsTypeExpr(E, DestTy: DstTy, BuiltinLoc, RParenLoc);
7427	}
7428
7429	/// Create a new AsTypeExpr node (bitcast) from the arguments.
7430	ExprResult Sema::BuildAsTypeExpr(Expr *E, QualType DestTy,
7431	SourceLocation BuiltinLoc,
7432	SourceLocation RParenLoc) {
7433	ExprValueKind VK = VK_PRValue;
7434	ExprObjectKind OK = OK_Ordinary;
7435	QualType SrcTy = E->getType();
7436	if (!SrcTy->isDependentType() &&
7437	Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy))
7438	return ExprError(
7439	Diag(BuiltinLoc, diag::err_invalid_astype_of_different_size)
7440	<< DestTy << SrcTy << E->getSourceRange());
7441	return new (Context) AsTypeExpr(E, DestTy, VK, OK, BuiltinLoc, RParenLoc);
7442	}
7443
7444	/// ActOnConvertVectorExpr - create a new convert-vector expression from the
7445	/// provided arguments.
7446	///
7447	/// __builtin_convertvector( value, dst type )
7448	///
7449	ExprResult Sema::ActOnConvertVectorExpr(Expr *E, ParsedType ParsedDestTy,
7450	SourceLocation BuiltinLoc,
7451	SourceLocation RParenLoc) {
7452	TypeSourceInfo *TInfo;
7453	GetTypeFromParser(Ty: ParsedDestTy, TInfo: &TInfo);
7454	return SemaConvertVectorExpr(E, TInfo, BuiltinLoc, RParenLoc);
7455	}
7456
7457	/// BuildResolvedCallExpr - Build a call to a resolved expression,
7458	/// i.e. an expression not of \p OverloadTy. The expression should
7459	/// unary-convert to an expression of function-pointer or
7460	/// block-pointer type.
7461	///
7462	/// \param NDecl the declaration being called, if available
7463	ExprResult Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl,
7464	SourceLocation LParenLoc,
7465	ArrayRef<Expr *> Args,
7466	SourceLocation RParenLoc, Expr *Config,
7467	bool IsExecConfig, ADLCallKind UsesADL) {
7468	FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(Val: NDecl);
7469	unsigned BuiltinID = (FDecl ? FDecl->getBuiltinID() : 0);
7470
7471	// Functions with 'interrupt' attribute cannot be called directly.
7472	if (FDecl && FDecl->hasAttr<AnyX86InterruptAttr>()) {
7473	Diag(Fn->getExprLoc(), diag::err_anyx86_interrupt_called);
7474	return ExprError();
7475	}
7476
7477	// Interrupt handlers don't save off the VFP regs automatically on ARM,
7478	// so there's some risk when calling out to non-interrupt handler functions
7479	// that the callee might not preserve them. This is easy to diagnose here,
7480	// but can be very challenging to debug.
7481	// Likewise, X86 interrupt handlers may only call routines with attribute
7482	// no_caller_saved_registers since there is no efficient way to
7483	// save and restore the non-GPR state.
7484	if (auto *Caller = getCurFunctionDecl()) {
7485	if (Caller->hasAttr<ARMInterruptAttr>()) {
7486	bool VFP = Context.getTargetInfo().hasFeature(Feature: "vfp");
7487	if (VFP && (!FDecl || !FDecl->hasAttr<ARMInterruptAttr>())) {
7488	Diag(Fn->getExprLoc(), diag::warn_arm_interrupt_calling_convention);
7489	if (FDecl)
7490	Diag(FDecl->getLocation(), diag::note_callee_decl) << FDecl;
7491	}
7492	}
7493	if (Caller->hasAttr<AnyX86InterruptAttr>() ||
7494	Caller->hasAttr<AnyX86NoCallerSavedRegistersAttr>()) {
7495	const TargetInfo &TI = Context.getTargetInfo();
7496	bool HasNonGPRRegisters =
7497	TI.hasFeature(Feature: "sse") || TI.hasFeature(Feature: "x87") || TI.hasFeature(Feature: "mmx");
7498	if (HasNonGPRRegisters &&
7499	(!FDecl || !FDecl->hasAttr<AnyX86NoCallerSavedRegistersAttr>())) {
7500	Diag(Fn->getExprLoc(), diag::warn_anyx86_excessive_regsave)
7501	<< (Caller->hasAttr<AnyX86InterruptAttr>() ? 0 : 1);
7502	if (FDecl)
7503	Diag(FDecl->getLocation(), diag::note_callee_decl) << FDecl;
7504	}
7505	}
7506	}
7507
7508	// Promote the function operand.
7509	// We special-case function promotion here because we only allow promoting
7510	// builtin functions to function pointers in the callee of a call.
7511	ExprResult Result;
7512	QualType ResultTy;
7513	if (BuiltinID &&
7514	Fn->getType()->isSpecificBuiltinType(K: BuiltinType::BuiltinFn)) {
7515	// Extract the return type from the (builtin) function pointer type.
7516	// FIXME Several builtins still have setType in
7517	// Sema::CheckBuiltinFunctionCall. One should review their definitions in
7518	// Builtins.td to ensure they are correct before removing setType calls.
7519	QualType FnPtrTy = Context.getPointerType(FDecl->getType());
7520	Result = ImpCastExprToType(E: Fn, Type: FnPtrTy, CK: CK_BuiltinFnToFnPtr).get();
7521	ResultTy = FDecl->getCallResultType();
7522	} else {
7523	Result = CallExprUnaryConversions(E: Fn);
7524	ResultTy = Context.BoolTy;
7525	}
7526	if (Result.isInvalid())
7527	return ExprError();
7528	Fn = Result.get();
7529
7530	// Check for a valid function type, but only if it is not a builtin which
7531	// requires custom type checking. These will be handled by
7532	// CheckBuiltinFunctionCall below just after creation of the call expression.
7533	const FunctionType *FuncT = nullptr;
7534	if (!BuiltinID || !Context.BuiltinInfo.hasCustomTypechecking(ID: BuiltinID)) {
7535	retry:
7536	if (const PointerType *PT = Fn->getType()->getAs<PointerType>()) {
7537	// C99 6.5.2.2p1 - "The expression that denotes the called function shall
7538	// have type pointer to function".
7539	FuncT = PT->getPointeeType()->getAs<FunctionType>();
7540	if (!FuncT)
7541	return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function)
7542	<< Fn->getType() << Fn->getSourceRange());
7543	} else if (const BlockPointerType *BPT =
7544	Fn->getType()->getAs<BlockPointerType>()) {
7545	FuncT = BPT->getPointeeType()->castAs<FunctionType>();
7546	} else {
7547	// Handle calls to expressions of unknown-any type.
7548	if (Fn->getType() == Context.UnknownAnyTy) {
7549	ExprResult rewrite = rebuildUnknownAnyFunction(S&: *this, fn: Fn);
7550	if (rewrite.isInvalid())
7551	return ExprError();
7552	Fn = rewrite.get();
7553	goto retry;
7554	}
7555
7556	return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function)
7557	<< Fn->getType() << Fn->getSourceRange());
7558	}
7559	}
7560
7561	// Get the number of parameters in the function prototype, if any.
7562	// We will allocate space for max(Args.size(), NumParams) arguments
7563	// in the call expression.
7564	const auto *Proto = dyn_cast_or_null<FunctionProtoType>(Val: FuncT);
7565	unsigned NumParams = Proto ? Proto->getNumParams() : 0;
7566
7567	CallExpr *TheCall;
7568	if (Config) {
7569	assert(UsesADL == ADLCallKind::NotADL &&
7570	"CUDAKernelCallExpr should not use ADL");
7571	TheCall = CUDAKernelCallExpr::Create(Ctx: Context, Fn, Config: cast<CallExpr>(Val: Config),
7572	Args, Ty: ResultTy, VK: VK_PRValue, RP: RParenLoc,
7573	FPFeatures: CurFPFeatureOverrides(), MinNumArgs: NumParams);
7574	} else {
7575	TheCall =
7576	CallExpr::Create(Ctx: Context, Fn, Args, Ty: ResultTy, VK: VK_PRValue, RParenLoc,
7577	FPFeatures: CurFPFeatureOverrides(), MinNumArgs: NumParams, UsesADL);
7578	}
7579
7580	if (!Context.isDependenceAllowed()) {
7581	// Forget about the nulled arguments since typo correction
7582	// do not handle them well.
7583	TheCall->shrinkNumArgs(NewNumArgs: Args.size());
7584	// C cannot always handle TypoExpr nodes in builtin calls and direct
7585	// function calls as their argument checking don't necessarily handle
7586	// dependent types properly, so make sure any TypoExprs have been
7587	// dealt with.
7588	ExprResult Result = CorrectDelayedTyposInExpr(TheCall);
7589	if (!Result.isUsable()) return ExprError();
7590	CallExpr *TheOldCall = TheCall;
7591	TheCall = dyn_cast<CallExpr>(Val: Result.get());
7592	bool CorrectedTypos = TheCall != TheOldCall;
7593	if (!TheCall) return Result;
7594	Args = llvm::ArrayRef(TheCall->getArgs(), TheCall->getNumArgs());
7595
7596	// A new call expression node was created if some typos were corrected.
7597	// However it may not have been constructed with enough storage. In this
7598	// case, rebuild the node with enough storage. The waste of space is
7599	// immaterial since this only happens when some typos were corrected.
7600	if (CorrectedTypos && Args.size() < NumParams) {
7601	if (Config)
7602	TheCall = CUDAKernelCallExpr::Create(
7603	Ctx: Context, Fn, Config: cast<CallExpr>(Val: Config), Args, Ty: ResultTy, VK: VK_PRValue,
7604	RP: RParenLoc, FPFeatures: CurFPFeatureOverrides(), MinNumArgs: NumParams);
7605	else
7606	TheCall =
7607	CallExpr::Create(Ctx: Context, Fn, Args, Ty: ResultTy, VK: VK_PRValue, RParenLoc,
7608	FPFeatures: CurFPFeatureOverrides(), MinNumArgs: NumParams, UsesADL);
7609	}
7610	// We can now handle the nulled arguments for the default arguments.
7611	TheCall->setNumArgsUnsafe(std::max<unsigned>(a: Args.size(), b: NumParams));
7612	}
7613
7614	// Bail out early if calling a builtin with custom type checking.
7615	if (BuiltinID && Context.BuiltinInfo.hasCustomTypechecking(ID: BuiltinID))
7616	return CheckBuiltinFunctionCall(FDecl, BuiltinID, TheCall);
7617
7618	if (getLangOpts().CUDA) {
7619	if (Config) {
7620	// CUDA: Kernel calls must be to global functions
7621	if (FDecl && !FDecl->hasAttr<CUDAGlobalAttr>())
7622	return ExprError(Diag(LParenLoc,diag::err_kern_call_not_global_function)
7623	<< FDecl << Fn->getSourceRange());
7624
7625	// CUDA: Kernel function must have 'void' return type
7626	if (!FuncT->getReturnType()->isVoidType() &&
7627	!FuncT->getReturnType()->getAs<AutoType>() &&
7628	!FuncT->getReturnType()->isInstantiationDependentType())
7629	return ExprError(Diag(LParenLoc, diag::err_kern_type_not_void_return)
7630	<< Fn->getType() << Fn->getSourceRange());
7631	} else {
7632	// CUDA: Calls to global functions must be configured
7633	if (FDecl && FDecl->hasAttr<CUDAGlobalAttr>())
7634	return ExprError(Diag(LParenLoc, diag::err_global_call_not_config)
7635	<< FDecl << Fn->getSourceRange());
7636	}
7637	}
7638
7639	// Check for a valid return type
7640	if (CheckCallReturnType(ReturnType: FuncT->getReturnType(), Loc: Fn->getBeginLoc(), CE: TheCall,
7641	FD: FDecl))
7642	return ExprError();
7643
7644	// We know the result type of the call, set it.
7645	TheCall->setType(FuncT->getCallResultType(Context));
7646	TheCall->setValueKind(Expr::getValueKindForType(T: FuncT->getReturnType()));
7647
7648	// WebAssembly tables can't be used as arguments.
7649	if (Context.getTargetInfo().getTriple().isWasm()) {
7650	for (const Expr *Arg : Args) {
7651	if (Arg && Arg->getType()->isWebAssemblyTableType()) {
7652	return ExprError(Diag(Arg->getExprLoc(),
7653	diag::err_wasm_table_as_function_parameter));
7654	}
7655	}
7656	}
7657
7658	if (Proto) {
7659	if (ConvertArgumentsForCall(Call: TheCall, Fn, FDecl, Proto, Args, RParenLoc,
7660	IsExecConfig))
7661	return ExprError();
7662	} else {
7663	assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!");
7664
7665	if (FDecl) {
7666	// Check if we have too few/too many template arguments, based
7667	// on our knowledge of the function definition.
7668	const FunctionDecl *Def = nullptr;
7669	if (FDecl->hasBody(Definition&: Def) && Args.size() != Def->param_size()) {
7670	Proto = Def->getType()->getAs<FunctionProtoType>();
7671	if (!Proto || !(Proto->isVariadic() && Args.size() >= Def->param_size()))
7672	Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments)
7673	<< (Args.size() > Def->param_size()) << FDecl << Fn->getSourceRange();
7674	}
7675
7676	// If the function we're calling isn't a function prototype, but we have
7677	// a function prototype from a prior declaratiom, use that prototype.
7678	if (!FDecl->hasPrototype())
7679	Proto = FDecl->getType()->getAs<FunctionProtoType>();
7680	}
7681
7682	// If we still haven't found a prototype to use but there are arguments to
7683	// the call, diagnose this as calling a function without a prototype.
7684	// However, if we found a function declaration, check to see if
7685	// -Wdeprecated-non-prototype was disabled where the function was declared.
7686	// If so, we will silence the diagnostic here on the assumption that this
7687	// interface is intentional and the user knows what they're doing. We will
7688	// also silence the diagnostic if there is a function declaration but it
7689	// was implicitly defined (the user already gets diagnostics about the
7690	// creation of the implicit function declaration, so the additional warning
7691	// is not helpful).
7692	if (!Proto && !Args.empty() &&
7693	(!FDecl || (!FDecl->isImplicit() &&
7694	!Diags.isIgnored(diag::warn_strict_uses_without_prototype,
7695	FDecl->getLocation()))))
7696	Diag(LParenLoc, diag::warn_strict_uses_without_prototype)
7697	<< (FDecl != nullptr) << FDecl;
7698
7699	// Promote the arguments (C99 6.5.2.2p6).
7700	for (unsigned i = 0, e = Args.size(); i != e; i++) {
7701	Expr *Arg = Args[i];
7702
7703	if (Proto && i < Proto->getNumParams()) {
7704	InitializedEntity Entity = InitializedEntity::InitializeParameter(
7705	Context, Type: Proto->getParamType(i), Consumed: Proto->isParamConsumed(I: i));
7706	ExprResult ArgE =
7707	PerformCopyInitialization(Entity, EqualLoc: SourceLocation(), Init: Arg);
7708	if (ArgE.isInvalid())
7709	return true;
7710
7711	Arg = ArgE.getAs<Expr>();
7712
7713	} else {
7714	ExprResult ArgE = DefaultArgumentPromotion(E: Arg);
7715
7716	if (ArgE.isInvalid())
7717	return true;
7718
7719	Arg = ArgE.getAs<Expr>();
7720	}
7721
7722	if (RequireCompleteType(Arg->getBeginLoc(), Arg->getType(),
7723	diag::err_call_incomplete_argument, Arg))
7724	return ExprError();
7725
7726	TheCall->setArg(Arg: i, ArgExpr: Arg);
7727	}
7728	TheCall->computeDependence();
7729	}
7730
7731	if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl))
7732	if (Method->isImplicitObjectMemberFunction())
7733	return ExprError(Diag(LParenLoc, diag::err_member_call_without_object)
7734	<< Fn->getSourceRange() << 0);
7735
7736	// Check for sentinels
7737	if (NDecl)
7738	DiagnoseSentinelCalls(D: NDecl, Loc: LParenLoc, Args);
7739
7740	// Warn for unions passing across security boundary (CMSE).
7741	if (FuncT != nullptr && FuncT->getCmseNSCallAttr()) {
7742	for (unsigned i = 0, e = Args.size(); i != e; i++) {
7743	if (const auto *RT =
7744	dyn_cast<RecordType>(Val: Args[i]->getType().getCanonicalType())) {
7745	if (RT->getDecl()->isOrContainsUnion())
7746	Diag(Args[i]->getBeginLoc(), diag::warn_cmse_nonsecure_union)
7747	<< 0 << i;
7748	}
7749	}
7750	}
7751
7752	// Do special checking on direct calls to functions.
7753	if (FDecl) {
7754	if (CheckFunctionCall(FDecl, TheCall, Proto))
7755	return ExprError();
7756
7757	checkFortifiedBuiltinMemoryFunction(FD: FDecl, TheCall);
7758
7759	if (BuiltinID)
7760	return CheckBuiltinFunctionCall(FDecl, BuiltinID, TheCall);
7761	} else if (NDecl) {
7762	if (CheckPointerCall(NDecl, TheCall, Proto))
7763	return ExprError();
7764	} else {
7765	if (CheckOtherCall(TheCall, Proto))
7766	return ExprError();
7767	}
7768
7769	return CheckForImmediateInvocation(E: MaybeBindToTemporary(TheCall), Decl: FDecl);
7770	}
7771
7772	ExprResult
7773	Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty,
7774	SourceLocation RParenLoc, Expr *InitExpr) {
7775	assert(Ty && "ActOnCompoundLiteral(): missing type");
7776	assert(InitExpr && "ActOnCompoundLiteral(): missing expression");
7777
7778	TypeSourceInfo *TInfo;
7779	QualType literalType = GetTypeFromParser(Ty, TInfo: &TInfo);
7780	if (!TInfo)
7781	TInfo = Context.getTrivialTypeSourceInfo(T: literalType);
7782
7783	return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, LiteralExpr: InitExpr);
7784	}
7785
7786	ExprResult
7787	Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo,
7788	SourceLocation RParenLoc, Expr *LiteralExpr) {
7789	QualType literalType = TInfo->getType();
7790
7791	if (literalType->isArrayType()) {
7792	if (RequireCompleteSizedType(
7793	LParenLoc, Context.getBaseElementType(literalType),
7794	diag::err_array_incomplete_or_sizeless_type,
7795	SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd())))
7796	return ExprError();
7797	if (literalType->isVariableArrayType()) {
7798	// C23 6.7.10p4: An entity of variable length array type shall not be
7799	// initialized except by an empty initializer.
7800	//
7801	// The C extension warnings are issued from ParseBraceInitializer() and
7802	// do not need to be issued here. However, we continue to issue an error
7803	// in the case there are initializers or we are compiling C++. We allow
7804	// use of VLAs in C++, but it's not clear we want to allow {} to zero
7805	// init a VLA in C++ in all cases (such as with non-trivial constructors).
7806	// FIXME: should we allow this construct in C++ when it makes sense to do
7807	// so?
7808	std::optional<unsigned> NumInits;
7809	if (const auto *ILE = dyn_cast<InitListExpr>(Val: LiteralExpr))
7810	NumInits = ILE->getNumInits();
7811	if ((LangOpts.CPlusPlus || NumInits.value_or(0)) &&
7812	!tryToFixVariablyModifiedVarType(TInfo, literalType, LParenLoc,
7813	diag::err_variable_object_no_init))
7814	return ExprError();
7815	}
7816	} else if (!literalType->isDependentType() &&
7817	RequireCompleteType(LParenLoc, literalType,
7818	diag::err_typecheck_decl_incomplete_type,
7819	SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd())))
7820	return ExprError();
7821
7822	InitializedEntity Entity
7823	= InitializedEntity::InitializeCompoundLiteralInit(TSI: TInfo);
7824	InitializationKind Kind
7825	= InitializationKind::CreateCStyleCast(StartLoc: LParenLoc,
7826	TypeRange: SourceRange(LParenLoc, RParenLoc),
7827	/*InitList=*/true);
7828	InitializationSequence InitSeq(*this, Entity, Kind, LiteralExpr);
7829	ExprResult Result = InitSeq.Perform(S&: *this, Entity, Kind, Args: LiteralExpr,
7830	ResultType: &literalType);
7831	if (Result.isInvalid())
7832	return ExprError();
7833	LiteralExpr = Result.get();
7834
7835	bool isFileScope = !CurContext->isFunctionOrMethod();
7836
7837	// In C, compound literals are l-values for some reason.
7838	// For GCC compatibility, in C++, file-scope array compound literals with
7839	// constant initializers are also l-values, and compound literals are
7840	// otherwise prvalues.
7841	//
7842	// (GCC also treats C++ list-initialized file-scope array prvalues with
7843	// constant initializers as l-values, but that's non-conforming, so we don't
7844	// follow it there.)
7845	//
7846	// FIXME: It would be better to handle the lvalue cases as materializing and
7847	// lifetime-extending a temporary object, but our materialized temporaries
7848	// representation only supports lifetime extension from a variable, not "out
7849	// of thin air".
7850	// FIXME: For C++, we might want to instead lifetime-extend only if a pointer
7851	// is bound to the result of applying array-to-pointer decay to the compound
7852	// literal.
7853	// FIXME: GCC supports compound literals of reference type, which should
7854	// obviously have a value kind derived from the kind of reference involved.
7855	ExprValueKind VK =
7856	(getLangOpts().CPlusPlus && !(isFileScope && literalType->isArrayType()))
7857	? VK_PRValue
7858	: VK_LValue;
7859
7860	if (isFileScope)
7861	if (auto ILE = dyn_cast<InitListExpr>(Val: LiteralExpr))
7862	for (unsigned i = 0, j = ILE->getNumInits(); i != j; i++) {
7863	Expr *Init = ILE->getInit(Init: i);
7864	ILE->setInit(i, ConstantExpr::Create(Context, E: Init));
7865	}
7866
7867	auto *E = new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType,
7868	VK, LiteralExpr, isFileScope);
7869	if (isFileScope) {
7870	if (!LiteralExpr->isTypeDependent() &&
7871	!LiteralExpr->isValueDependent() &&
7872	!literalType->isDependentType()) // C99 6.5.2.5p3
7873	if (CheckForConstantInitializer(e: LiteralExpr, t: literalType))
7874	return ExprError();
7875	} else if (literalType.getAddressSpace() != LangAS::opencl_private &&
7876	literalType.getAddressSpace() != LangAS::Default) {
7877	// Embedded-C extensions to C99 6.5.2.5:
7878	// "If the compound literal occurs inside the body of a function, the
7879	// type name shall not be qualified by an address-space qualifier."
7880	Diag(LParenLoc, diag::err_compound_literal_with_address_space)
7881	<< SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd());
7882	return ExprError();
7883	}
7884
7885	if (!isFileScope && !getLangOpts().CPlusPlus) {
7886	// Compound literals that have automatic storage duration are destroyed at
7887	// the end of the scope in C; in C++, they're just temporaries.
7888
7889	// Emit diagnostics if it is or contains a C union type that is non-trivial
7890	// to destruct.
7891	if (E->getType().hasNonTrivialToPrimitiveDestructCUnion())
7892	checkNonTrivialCUnion(QT: E->getType(), Loc: E->getExprLoc(),
7893	UseContext: NTCUC_CompoundLiteral, NonTrivialKind: NTCUK_Destruct);
7894
7895	// Diagnose jumps that enter or exit the lifetime of the compound literal.
7896	if (literalType.isDestructedType()) {
7897	Cleanup.setExprNeedsCleanups(true);
7898	ExprCleanupObjects.push_back(Elt: E);
7899	getCurFunction()->setHasBranchProtectedScope();
7900	}
7901	}
7902
7903	if (E->getType().hasNonTrivialToPrimitiveDefaultInitializeCUnion() ||
7904	E->getType().hasNonTrivialToPrimitiveCopyCUnion())
7905	checkNonTrivialCUnionInInitializer(Init: E->getInitializer(),
7906	Loc: E->getInitializer()->getExprLoc());
7907
7908	return MaybeBindToTemporary(E);
7909	}
7910
7911	ExprResult
7912	Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg InitArgList,
7913	SourceLocation RBraceLoc) {
7914	// Only produce each kind of designated initialization diagnostic once.
7915	SourceLocation FirstDesignator;
7916	bool DiagnosedArrayDesignator = false;
7917	bool DiagnosedNestedDesignator = false;
7918	bool DiagnosedMixedDesignator = false;
7919
7920	// Check that any designated initializers are syntactically valid in the
7921	// current language mode.
7922	for (unsigned I = 0, E = InitArgList.size(); I != E; ++I) {
7923	if (auto *DIE = dyn_cast<DesignatedInitExpr>(Val: InitArgList[I])) {
7924	if (FirstDesignator.isInvalid())
7925	FirstDesignator = DIE->getBeginLoc();
7926
7927	if (!getLangOpts().CPlusPlus)
7928	break;
7929
7930	if (!DiagnosedNestedDesignator && DIE->size() > 1) {
7931	DiagnosedNestedDesignator = true;
7932	Diag(DIE->getBeginLoc(), diag::ext_designated_init_nested)
7933	<< DIE->getDesignatorsSourceRange();
7934	}
7935
7936	for (auto &Desig : DIE->designators()) {
7937	if (!Desig.isFieldDesignator() && !DiagnosedArrayDesignator) {
7938	DiagnosedArrayDesignator = true;
7939	Diag(Desig.getBeginLoc(), diag::ext_designated_init_array)
7940	<< Desig.getSourceRange();
7941	}
7942	}
7943
7944	if (!DiagnosedMixedDesignator &&
7945	!isa<DesignatedInitExpr>(Val: InitArgList[0])) {
7946	DiagnosedMixedDesignator = true;
7947	Diag(DIE->getBeginLoc(), diag::ext_designated_init_mixed)
7948	<< DIE->getSourceRange();
7949	Diag(InitArgList[0]->getBeginLoc(), diag::note_designated_init_mixed)
7950	<< InitArgList[0]->getSourceRange();
7951	}
7952	} else if (getLangOpts().CPlusPlus && !DiagnosedMixedDesignator &&
7953	isa<DesignatedInitExpr>(Val: InitArgList[0])) {
7954	DiagnosedMixedDesignator = true;
7955	auto *DIE = cast<DesignatedInitExpr>(Val: InitArgList[0]);
7956	Diag(DIE->getBeginLoc(), diag::ext_designated_init_mixed)
7957	<< DIE->getSourceRange();
7958	Diag(InitArgList[I]->getBeginLoc(), diag::note_designated_init_mixed)
7959	<< InitArgList[I]->getSourceRange();
7960	}
7961	}
7962
7963	if (FirstDesignator.isValid()) {
7964	// Only diagnose designated initiaization as a C++20 extension if we didn't
7965	// already diagnose use of (non-C++20) C99 designator syntax.
7966	if (getLangOpts().CPlusPlus && !DiagnosedArrayDesignator &&
7967	!DiagnosedNestedDesignator && !DiagnosedMixedDesignator) {
7968	Diag(FirstDesignator, getLangOpts().CPlusPlus20
7969	? diag::warn_cxx17_compat_designated_init
7970	: diag::ext_cxx_designated_init);
7971	} else if (!getLangOpts().CPlusPlus && !getLangOpts().C99) {
7972	Diag(FirstDesignator, diag::ext_designated_init);
7973	}
7974	}
7975
7976	return BuildInitList(LBraceLoc, InitArgList, RBraceLoc);
7977	}
7978
7979	ExprResult
7980	Sema::BuildInitList(SourceLocation LBraceLoc, MultiExprArg InitArgList,
7981	SourceLocation RBraceLoc) {
7982	// Semantic analysis for initializers is done by ActOnDeclarator() and
7983	// CheckInitializer() - it requires knowledge of the object being initialized.
7984
7985	// Immediately handle non-overload placeholders. Overloads can be
7986	// resolved contextually, but everything else here can't.
7987	for (unsigned I = 0, E = InitArgList.size(); I != E; ++I) {
7988	if (InitArgList[I]->getType()->isNonOverloadPlaceholderType()) {
7989	ExprResult result = CheckPlaceholderExpr(E: InitArgList[I]);
7990
7991	// Ignore failures; dropping the entire initializer list because
7992	// of one failure would be terrible for indexing/etc.
7993	if (result.isInvalid()) continue;
7994
7995	InitArgList[I] = result.get();
7996	}
7997	}
7998
7999	InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitArgList,
8000	RBraceLoc);
8001	E->setType(Context.VoidTy); // FIXME: just a place holder for now.
8002	return E;
8003	}
8004
8005	/// Do an explicit extend of the given block pointer if we're in ARC.
8006	void Sema::maybeExtendBlockObject(ExprResult &E) {
8007	assert(E.get()->getType()->isBlockPointerType());
8008	assert(E.get()->isPRValue());
8009
8010	// Only do this in an r-value context.
8011	if (!getLangOpts().ObjCAutoRefCount) return;
8012
8013	E = ImplicitCastExpr::Create(
8014	Context, T: E.get()->getType(), Kind: CK_ARCExtendBlockObject, Operand: E.get(),
8015	/*base path*/ BasePath: nullptr, Cat: VK_PRValue, FPO: FPOptionsOverride());
8016	Cleanup.setExprNeedsCleanups(true);
8017	}
8018
8019	/// Prepare a conversion of the given expression to an ObjC object
8020	/// pointer type.
8021	CastKind Sema::PrepareCastToObjCObjectPointer(ExprResult &E) {
8022	QualType type = E.get()->getType();
8023	if (type->isObjCObjectPointerType()) {
8024	return CK_BitCast;
8025	} else if (type->isBlockPointerType()) {
8026	maybeExtendBlockObject(E);
8027	return CK_BlockPointerToObjCPointerCast;
8028	} else {
8029	assert(type->isPointerType());
8030	return CK_CPointerToObjCPointerCast;
8031	}
8032	}
8033
8034	/// Prepares for a scalar cast, performing all the necessary stages
8035	/// except the final cast and returning the kind required.
8036	CastKind Sema::PrepareScalarCast(ExprResult &Src, QualType DestTy) {
8037	// Both Src and Dest are scalar types, i.e. arithmetic or pointer.
8038	// Also, callers should have filtered out the invalid cases with
8039	// pointers. Everything else should be possible.
8040
8041	QualType SrcTy = Src.get()->getType();
8042	if (Context.hasSameUnqualifiedType(T1: SrcTy, T2: DestTy))
8043	return CK_NoOp;
8044
8045	switch (Type::ScalarTypeKind SrcKind = SrcTy->getScalarTypeKind()) {
8046	case Type::STK_MemberPointer:
8047	llvm_unreachable("member pointer type in C");
8048
8049	case Type::STK_CPointer:
8050	case Type::STK_BlockPointer:
8051	case Type::STK_ObjCObjectPointer:
8052	switch (DestTy->getScalarTypeKind()) {
8053	case Type::STK_CPointer: {
8054	LangAS SrcAS = SrcTy->getPointeeType().getAddressSpace();
8055	LangAS DestAS = DestTy->getPointeeType().getAddressSpace();
8056	if (SrcAS != DestAS)
8057	return CK_AddressSpaceConversion;
8058	if (Context.hasCvrSimilarType(T1: SrcTy, T2: DestTy))
8059	return CK_NoOp;
8060	return CK_BitCast;
8061	}
8062	case Type::STK_BlockPointer:
8063	return (SrcKind == Type::STK_BlockPointer
8064	? CK_BitCast : CK_AnyPointerToBlockPointerCast);
8065	case Type::STK_ObjCObjectPointer:
8066	if (SrcKind == Type::STK_ObjCObjectPointer)
8067	return CK_BitCast;
8068	if (SrcKind == Type::STK_CPointer)
8069	return CK_CPointerToObjCPointerCast;
8070	maybeExtendBlockObject(E&: Src);
8071	return CK_BlockPointerToObjCPointerCast;
8072	case Type::STK_Bool:
8073	return CK_PointerToBoolean;
8074	case Type::STK_Integral:
8075	return CK_PointerToIntegral;
8076	case Type::STK_Floating:
8077	case Type::STK_FloatingComplex:
8078	case Type::STK_IntegralComplex:
8079	case Type::STK_MemberPointer:
8080	case Type::STK_FixedPoint:
8081	llvm_unreachable("illegal cast from pointer");
8082	}
8083	llvm_unreachable("Should have returned before this");
8084
8085	case Type::STK_FixedPoint:
8086	switch (DestTy->getScalarTypeKind()) {
8087	case Type::STK_FixedPoint:
8088	return CK_FixedPointCast;
8089	case Type::STK_Bool:
8090	return CK_FixedPointToBoolean;
8091	case Type::STK_Integral:
8092	return CK_FixedPointToIntegral;
8093	case Type::STK_Floating:
8094	return CK_FixedPointToFloating;
8095	case Type::STK_IntegralComplex:
8096	case Type::STK_FloatingComplex:
8097	Diag(Src.get()->getExprLoc(),
8098	diag::err_unimplemented_conversion_with_fixed_point_type)
8099	<< DestTy;
8100	return CK_IntegralCast;
8101	case Type::STK_CPointer:
8102	case Type::STK_ObjCObjectPointer:
8103	case Type::STK_BlockPointer:
8104	case Type::STK_MemberPointer:
8105	llvm_unreachable("illegal cast to pointer type");
8106	}
8107	llvm_unreachable("Should have returned before this");
8108
8109	case Type::STK_Bool: // casting from bool is like casting from an integer
8110	case Type::STK_Integral:
8111	switch (DestTy->getScalarTypeKind()) {
8112	case Type::STK_CPointer:
8113	case Type::STK_ObjCObjectPointer:
8114	case Type::STK_BlockPointer:
8115	if (Src.get()->isNullPointerConstant(Ctx&: Context,
8116	NPC: Expr::NPC_ValueDependentIsNull))
8117	return CK_NullToPointer;
8118	return CK_IntegralToPointer;
8119	case Type::STK_Bool:
8120	return CK_IntegralToBoolean;
8121	case Type::STK_Integral:
8122	return CK_IntegralCast;
8123	case Type::STK_Floating:
8124	return CK_IntegralToFloating;
8125	case Type::STK_IntegralComplex:
8126	Src = ImpCastExprToType(E: Src.get(),
8127	Type: DestTy->castAs<ComplexType>()->getElementType(),
8128	CK: CK_IntegralCast);
8129	return CK_IntegralRealToComplex;
8130	case Type::STK_FloatingComplex:
8131	Src = ImpCastExprToType(E: Src.get(),
8132	Type: DestTy->castAs<ComplexType>()->getElementType(),
8133	CK: CK_IntegralToFloating);
8134	return CK_FloatingRealToComplex;
8135	case Type::STK_MemberPointer:
8136	llvm_unreachable("member pointer type in C");
8137	case Type::STK_FixedPoint:
8138	return CK_IntegralToFixedPoint;
8139	}
8140	llvm_unreachable("Should have returned before this");
8141
8142	case Type::STK_Floating:
8143	switch (DestTy->getScalarTypeKind()) {
8144	case Type::STK_Floating:
8145	return CK_FloatingCast;
8146	case Type::STK_Bool:
8147	return CK_FloatingToBoolean;
8148	case Type::STK_Integral:
8149	return CK_FloatingToIntegral;
8150	case Type::STK_FloatingComplex:
8151	Src = ImpCastExprToType(E: Src.get(),
8152	Type: DestTy->castAs<ComplexType>()->getElementType(),
8153	CK: CK_FloatingCast);
8154	return CK_FloatingRealToComplex;
8155	case Type::STK_IntegralComplex:
8156	Src = ImpCastExprToType(E: Src.get(),
8157	Type: DestTy->castAs<ComplexType>()->getElementType(),
8158	CK: CK_FloatingToIntegral);
8159	return CK_IntegralRealToComplex;
8160	case Type::STK_CPointer:
8161	case Type::STK_ObjCObjectPointer:
8162	case Type::STK_BlockPointer:
8163	llvm_unreachable("valid float->pointer cast?");
8164	case Type::STK_MemberPointer:
8165	llvm_unreachable("member pointer type in C");
8166	case Type::STK_FixedPoint:
8167	return CK_FloatingToFixedPoint;
8168	}
8169	llvm_unreachable("Should have returned before this");
8170
8171	case Type::STK_FloatingComplex:
8172	switch (DestTy->getScalarTypeKind()) {
8173	case Type::STK_FloatingComplex:
8174	return CK_FloatingComplexCast;
8175	case Type::STK_IntegralComplex:
8176	return CK_FloatingComplexToIntegralComplex;
8177	case Type::STK_Floating: {
8178	QualType ET = SrcTy->castAs<ComplexType>()->getElementType();
8179	if (Context.hasSameType(T1: ET, T2: DestTy))
8180	return CK_FloatingComplexToReal;
8181	Src = ImpCastExprToType(E: Src.get(), Type: ET, CK: CK_FloatingComplexToReal);
8182	return CK_FloatingCast;
8183	}
8184	case Type::STK_Bool:
8185	return CK_FloatingComplexToBoolean;
8186	case Type::STK_Integral:
8187	Src = ImpCastExprToType(E: Src.get(),
8188	Type: SrcTy->castAs<ComplexType>()->getElementType(),
8189	CK: CK_FloatingComplexToReal);
8190	return CK_FloatingToIntegral;
8191	case Type::STK_CPointer:
8192	case Type::STK_ObjCObjectPointer:
8193	case Type::STK_BlockPointer:
8194	llvm_unreachable("valid complex float->pointer cast?");
8195	case Type::STK_MemberPointer:
8196	llvm_unreachable("member pointer type in C");
8197	case Type::STK_FixedPoint:
8198	Diag(Src.get()->getExprLoc(),
8199	diag::err_unimplemented_conversion_with_fixed_point_type)
8200	<< SrcTy;
8201	return CK_IntegralCast;
8202	}
8203	llvm_unreachable("Should have returned before this");
8204
8205	case Type::STK_IntegralComplex:
8206	switch (DestTy->getScalarTypeKind()) {
8207	case Type::STK_FloatingComplex:
8208	return CK_IntegralComplexToFloatingComplex;
8209	case Type::STK_IntegralComplex:
8210	return CK_IntegralComplexCast;
8211	case Type::STK_Integral: {
8212	QualType ET = SrcTy->castAs<ComplexType>()->getElementType();
8213	if (Context.hasSameType(T1: ET, T2: DestTy))
8214	return CK_IntegralComplexToReal;
8215	Src = ImpCastExprToType(E: Src.get(), Type: ET, CK: CK_IntegralComplexToReal);
8216	return CK_IntegralCast;
8217	}
8218	case Type::STK_Bool:
8219	return CK_IntegralComplexToBoolean;
8220	case Type::STK_Floating:
8221	Src = ImpCastExprToType(E: Src.get(),
8222	Type: SrcTy->castAs<ComplexType>()->getElementType(),
8223	CK: CK_IntegralComplexToReal);
8224	return CK_IntegralToFloating;
8225	case Type::STK_CPointer:
8226	case Type::STK_ObjCObjectPointer:
8227	case Type::STK_BlockPointer:
8228	llvm_unreachable("valid complex int->pointer cast?");
8229	case Type::STK_MemberPointer:
8230	llvm_unreachable("member pointer type in C");
8231	case Type::STK_FixedPoint:
8232	Diag(Src.get()->getExprLoc(),
8233	diag::err_unimplemented_conversion_with_fixed_point_type)
8234	<< SrcTy;
8235	return CK_IntegralCast;
8236	}
8237	llvm_unreachable("Should have returned before this");
8238	}
8239
8240	llvm_unreachable("Unhandled scalar cast");
8241	}
8242
8243	static bool breakDownVectorType(QualType type, uint64_t &len,
8244	QualType &eltType) {
8245	// Vectors are simple.
8246	if (const VectorType *vecType = type->getAs<VectorType>()) {
8247	len = vecType->getNumElements();
8248	eltType = vecType->getElementType();
8249	assert(eltType->isScalarType());
8250	return true;
8251	}
8252
8253	// We allow lax conversion to and from non-vector types, but only if
8254	// they're real types (i.e. non-complex, non-pointer scalar types).
8255	if (!type->isRealType()) return false;
8256
8257	len = 1;
8258	eltType = type;
8259	return true;
8260	}
8261
8262	/// Are the two types SVE-bitcast-compatible types? I.e. is bitcasting from the
8263	/// first SVE type (e.g. an SVE VLAT) to the second type (e.g. an SVE VLST)
8264	/// allowed?
8265	///
8266	/// This will also return false if the two given types do not make sense from
8267	/// the perspective of SVE bitcasts.
8268	bool Sema::isValidSveBitcast(QualType srcTy, QualType destTy) {
8269	assert(srcTy->isVectorType() || destTy->isVectorType());
8270
8271	auto ValidScalableConversion = [](QualType FirstType, QualType SecondType) {
8272	if (!FirstType->isSVESizelessBuiltinType())
8273	return false;
8274
8275	const auto *VecTy = SecondType->getAs<VectorType>();
8276	return VecTy && VecTy->getVectorKind() == VectorKind::SveFixedLengthData;
8277	};
8278
8279	return ValidScalableConversion(srcTy, destTy) ||
8280	ValidScalableConversion(destTy, srcTy);
8281	}
8282
8283	/// Are the two types RVV-bitcast-compatible types? I.e. is bitcasting from the
8284	/// first RVV type (e.g. an RVV scalable type) to the second type (e.g. an RVV
8285	/// VLS type) allowed?
8286	///
8287	/// This will also return false if the two given types do not make sense from
8288	/// the perspective of RVV bitcasts.
8289	bool Sema::isValidRVVBitcast(QualType srcTy, QualType destTy) {
8290	assert(srcTy->isVectorType() || destTy->isVectorType());
8291
8292	auto ValidScalableConversion = [](QualType FirstType, QualType SecondType) {
8293	if (!FirstType->isRVVSizelessBuiltinType())
8294	return false;
8295
8296	const auto *VecTy = SecondType->getAs<VectorType>();
8297	return VecTy && VecTy->getVectorKind() == VectorKind::RVVFixedLengthData;
8298	};
8299
8300	return ValidScalableConversion(srcTy, destTy) ||
8301	ValidScalableConversion(destTy, srcTy);
8302	}
8303
8304	/// Are the two types matrix types and do they have the same dimensions i.e.
8305	/// do they have the same number of rows and the same number of columns?
8306	bool Sema::areMatrixTypesOfTheSameDimension(QualType srcTy, QualType destTy) {
8307	if (!destTy->isMatrixType() || !srcTy->isMatrixType())
8308	return false;
8309
8310	const ConstantMatrixType *matSrcType = srcTy->getAs<ConstantMatrixType>();
8311	const ConstantMatrixType *matDestType = destTy->getAs<ConstantMatrixType>();
8312
8313	return matSrcType->getNumRows() == matDestType->getNumRows() &&
8314	matSrcType->getNumColumns() == matDestType->getNumColumns();
8315	}
8316
8317	bool Sema::areVectorTypesSameSize(QualType SrcTy, QualType DestTy) {
8318	assert(DestTy->isVectorType() || SrcTy->isVectorType());
8319
8320	uint64_t SrcLen, DestLen;
8321	QualType SrcEltTy, DestEltTy;
8322	if (!breakDownVectorType(type: SrcTy, len&: SrcLen, eltType&: SrcEltTy))
8323	return false;
8324	if (!breakDownVectorType(type: DestTy, len&: DestLen, eltType&: DestEltTy))
8325	return false;
8326
8327	// ASTContext::getTypeSize will return the size rounded up to a
8328	// power of 2, so instead of using that, we need to use the raw
8329	// element size multiplied by the element count.
8330	uint64_t SrcEltSize = Context.getTypeSize(T: SrcEltTy);
8331	uint64_t DestEltSize = Context.getTypeSize(T: DestEltTy);
8332
8333	return (SrcLen * SrcEltSize == DestLen * DestEltSize);
8334	}
8335
8336	// This returns true if at least one of the types is an altivec vector.
8337	bool Sema::anyAltivecTypes(QualType SrcTy, QualType DestTy) {
8338	assert((DestTy->isVectorType() || SrcTy->isVectorType()) &&
8339	"expected at least one type to be a vector here");
8340
8341	bool IsSrcTyAltivec =
8342	SrcTy->isVectorType() && ((SrcTy->castAs<VectorType>()->getVectorKind() ==
8343	VectorKind::AltiVecVector) ||
8344	(SrcTy->castAs<VectorType>()->getVectorKind() ==
8345	VectorKind::AltiVecBool) ||
8346	(SrcTy->castAs<VectorType>()->getVectorKind() ==
8347	VectorKind::AltiVecPixel));
8348
8349	bool IsDestTyAltivec = DestTy->isVectorType() &&
8350	((DestTy->castAs<VectorType>()->getVectorKind() ==
8351	VectorKind::AltiVecVector) ||
8352	(DestTy->castAs<VectorType>()->getVectorKind() ==
8353	VectorKind::AltiVecBool) ||
8354	(DestTy->castAs<VectorType>()->getVectorKind() ==
8355	VectorKind::AltiVecPixel));
8356
8357	return (IsSrcTyAltivec || IsDestTyAltivec);
8358	}
8359
8360	/// Are the two types lax-compatible vector types? That is, given
8361	/// that one of them is a vector, do they have equal storage sizes,
8362	/// where the storage size is the number of elements times the element
8363	/// size?
8364	///
8365	/// This will also return false if either of the types is neither a
8366	/// vector nor a real type.
8367	bool Sema::areLaxCompatibleVectorTypes(QualType srcTy, QualType destTy) {
8368	assert(destTy->isVectorType() || srcTy->isVectorType());
8369
8370	// Disallow lax conversions between scalars and ExtVectors (these
8371	// conversions are allowed for other vector types because common headers
8372	// depend on them). Most scalar OP ExtVector cases are handled by the
8373	// splat path anyway, which does what we want (convert, not bitcast).
8374	// What this rules out for ExtVectors is crazy things like char4*float.
8375	if (srcTy->isScalarType() && destTy->isExtVectorType()) return false;
8376	if (destTy->isScalarType() && srcTy->isExtVectorType()) return false;
8377
8378	return areVectorTypesSameSize(SrcTy: srcTy, DestTy: destTy);
8379	}
8380
8381	/// Is this a legal conversion between two types, one of which is
8382	/// known to be a vector type?
8383	bool Sema::isLaxVectorConversion(QualType srcTy, QualType destTy) {
8384	assert(destTy->isVectorType() || srcTy->isVectorType());
8385
8386	switch (Context.getLangOpts().getLaxVectorConversions()) {
8387	case LangOptions::LaxVectorConversionKind::None:
8388	return false;
8389
8390	case LangOptions::LaxVectorConversionKind::Integer:
8391	if (!srcTy->isIntegralOrEnumerationType()) {
8392	auto *Vec = srcTy->getAs<VectorType>();
8393	if (!Vec || !Vec->getElementType()->isIntegralOrEnumerationType())
8394	return false;
8395	}
8396	if (!destTy->isIntegralOrEnumerationType()) {
8397	auto *Vec = destTy->getAs<VectorType>();
8398	if (!Vec || !Vec->getElementType()->isIntegralOrEnumerationType())
8399	return false;
8400	}
8401	// OK, integer (vector) -> integer (vector) bitcast.
8402	break;
8403
8404	case LangOptions::LaxVectorConversionKind::All:
8405	break;
8406	}
8407
8408	return areLaxCompatibleVectorTypes(srcTy, destTy);
8409	}
8410
8411	bool Sema::CheckMatrixCast(SourceRange R, QualType DestTy, QualType SrcTy,
8412	CastKind &Kind) {
8413	if (SrcTy->isMatrixType() && DestTy->isMatrixType()) {
8414	if (!areMatrixTypesOfTheSameDimension(srcTy: SrcTy, destTy: DestTy)) {
8415	return Diag(R.getBegin(), diag::err_invalid_conversion_between_matrixes)
8416	<< DestTy << SrcTy << R;
8417	}
8418	} else if (SrcTy->isMatrixType()) {
8419	return Diag(R.getBegin(),
8420	diag::err_invalid_conversion_between_matrix_and_type)
8421	<< SrcTy << DestTy << R;
8422	} else if (DestTy->isMatrixType()) {
8423	return Diag(R.getBegin(),
8424	diag::err_invalid_conversion_between_matrix_and_type)
8425	<< DestTy << SrcTy << R;
8426	}
8427
8428	Kind = CK_MatrixCast;
8429	return false;
8430	}
8431
8432	bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty,
8433	CastKind &Kind) {
8434	assert(VectorTy->isVectorType() && "Not a vector type!");
8435
8436	if (Ty->isVectorType() || Ty->isIntegralType(Ctx: Context)) {
8437	if (!areLaxCompatibleVectorTypes(Ty, VectorTy))
8438	return Diag(R.getBegin(),
8439	Ty->isVectorType() ?
8440	diag::err_invalid_conversion_between_vectors :
8441	diag::err_invalid_conversion_between_vector_and_integer)
8442	<< VectorTy << Ty << R;
8443	} else
8444	return Diag(R.getBegin(),
8445	diag::err_invalid_conversion_between_vector_and_scalar)
8446	<< VectorTy << Ty << R;
8447
8448	Kind = CK_BitCast;
8449	return false;
8450	}
8451
8452	ExprResult Sema::prepareVectorSplat(QualType VectorTy, Expr *SplattedExpr) {
8453	QualType DestElemTy = VectorTy->castAs<VectorType>()->getElementType();
8454
8455	if (DestElemTy == SplattedExpr->getType())
8456	return SplattedExpr;
8457
8458	assert(DestElemTy->isFloatingType() ||
8459	DestElemTy->isIntegralOrEnumerationType());
8460
8461	CastKind CK;
8462	if (VectorTy->isExtVectorType() && SplattedExpr->getType()->isBooleanType()) {
8463	// OpenCL requires that we convert `true` boolean expressions to -1, but
8464	// only when splatting vectors.
8465	if (DestElemTy->isFloatingType()) {
8466	// To avoid having to have a CK_BooleanToSignedFloating cast kind, we cast
8467	// in two steps: boolean to signed integral, then to floating.
8468	ExprResult CastExprRes = ImpCastExprToType(E: SplattedExpr, Type: Context.IntTy,
8469	CK: CK_BooleanToSignedIntegral);
8470	SplattedExpr = CastExprRes.get();
8471	CK = CK_IntegralToFloating;
8472	} else {
8473	CK = CK_BooleanToSignedIntegral;
8474	}
8475	} else {
8476	ExprResult CastExprRes = SplattedExpr;
8477	CK = PrepareScalarCast(Src&: CastExprRes, DestTy: DestElemTy);
8478	if (CastExprRes.isInvalid())
8479	return ExprError();
8480	SplattedExpr = CastExprRes.get();
8481	}
8482	return ImpCastExprToType(E: SplattedExpr, Type: DestElemTy, CK);
8483	}
8484
8485	ExprResult Sema::CheckExtVectorCast(SourceRange R, QualType DestTy,
8486	Expr *CastExpr, CastKind &Kind) {
8487	assert(DestTy->isExtVectorType() && "Not an extended vector type!");
8488
8489	QualType SrcTy = CastExpr->getType();
8490
8491	// If SrcTy is a VectorType, the total size must match to explicitly cast to
8492	// an ExtVectorType.
8493	// In OpenCL, casts between vectors of different types are not allowed.
8494	// (See OpenCL 6.2).
8495	if (SrcTy->isVectorType()) {
8496	if (!areLaxCompatibleVectorTypes(srcTy: SrcTy, destTy: DestTy) ||
8497	(getLangOpts().OpenCL &&
8498	!Context.hasSameUnqualifiedType(T1: DestTy, T2: SrcTy))) {
8499	Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors)
8500	<< DestTy << SrcTy << R;
8501	return ExprError();
8502	}
8503	Kind = CK_BitCast;
8504	return CastExpr;
8505	}
8506
8507	// All non-pointer scalars can be cast to ExtVector type. The appropriate
8508	// conversion will take place first from scalar to elt type, and then
8509	// splat from elt type to vector.
8510	if (SrcTy->isPointerType())
8511	return Diag(R.getBegin(),
8512	diag::err_invalid_conversion_between_vector_and_scalar)
8513	<< DestTy << SrcTy << R;
8514
8515	Kind = CK_VectorSplat;
8516	return prepareVectorSplat(VectorTy: DestTy, SplattedExpr: CastExpr);
8517	}
8518
8519	ExprResult
8520	Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc,
8521	Declarator &D, ParsedType &Ty,
8522	SourceLocation RParenLoc, Expr *CastExpr) {
8523	assert(!D.isInvalidType() && (CastExpr != nullptr) &&
8524	"ActOnCastExpr(): missing type or expr");
8525
8526	TypeSourceInfo *castTInfo = GetTypeForDeclaratorCast(D, FromTy: CastExpr->getType());
8527	if (D.isInvalidType())
8528	return ExprError();
8529
8530	if (getLangOpts().CPlusPlus) {
8531	// Check that there are no default arguments (C++ only).
8532	CheckExtraCXXDefaultArguments(D);
8533	} else {
8534	// Make sure any TypoExprs have been dealt with.
8535	ExprResult Res = CorrectDelayedTyposInExpr(E: CastExpr);
8536	if (!Res.isUsable())
8537	return ExprError();
8538	CastExpr = Res.get();
8539	}
8540
8541	checkUnusedDeclAttributes(D);
8542
8543	QualType castType = castTInfo->getType();
8544	Ty = CreateParsedType(T: castType, TInfo: castTInfo);
8545
8546	bool isVectorLiteral = false;
8547
8548	// Check for an altivec or OpenCL literal,
8549	// i.e. all the elements are integer constants.
8550	ParenExpr *PE = dyn_cast<ParenExpr>(Val: CastExpr);
8551	ParenListExpr *PLE = dyn_cast<ParenListExpr>(Val: CastExpr);
8552	if ((getLangOpts().AltiVec || getLangOpts().ZVector || getLangOpts().OpenCL)
8553	&& castType->isVectorType() && (PE || PLE)) {
8554	if (PLE && PLE->getNumExprs() == 0) {
8555	Diag(PLE->getExprLoc(), diag::err_altivec_empty_initializer);
8556	return ExprError();
8557	}
8558	if (PE || PLE->getNumExprs() == 1) {
8559	Expr *E = (PE ? PE->getSubExpr() : PLE->getExpr(Init: 0));
8560	if (!E->isTypeDependent() && !E->getType()->isVectorType())
8561	isVectorLiteral = true;
8562	}
8563	else
8564	isVectorLiteral = true;
8565	}
8566
8567	// If this is a vector initializer, '(' type ')' '(' init, ..., init ')'
8568	// then handle it as such.
8569	if (isVectorLiteral)
8570	return BuildVectorLiteral(LParenLoc, RParenLoc, E: CastExpr, TInfo: castTInfo);
8571
8572	// If the Expr being casted is a ParenListExpr, handle it specially.
8573	// This is not an AltiVec-style cast, so turn the ParenListExpr into a
8574	// sequence of BinOp comma operators.
8575	if (isa<ParenListExpr>(Val: CastExpr)) {
8576	ExprResult Result = MaybeConvertParenListExprToParenExpr(S, ME: CastExpr);
8577	if (Result.isInvalid()) return ExprError();
8578	CastExpr = Result.get();
8579	}
8580
8581	if (getLangOpts().CPlusPlus && !castType->isVoidType())
8582	Diag(LParenLoc, diag::warn_old_style_cast) << CastExpr->getSourceRange();
8583
8584	CheckTollFreeBridgeCast(castType, castExpr: CastExpr);
8585
8586	CheckObjCBridgeRelatedCast(castType, castExpr: CastExpr);
8587
8588	DiscardMisalignedMemberAddress(T: castType.getTypePtr(), E: CastExpr);
8589
8590	return BuildCStyleCastExpr(LParenLoc, Ty: castTInfo, RParenLoc, Op: CastExpr);
8591	}
8592
8593	ExprResult Sema::BuildVectorLiteral(SourceLocation LParenLoc,
8594	SourceLocation RParenLoc, Expr *E,
8595	TypeSourceInfo *TInfo) {
8596	assert((isa<ParenListExpr>(E) || isa<ParenExpr>(E)) &&
8597	"Expected paren or paren list expression");
8598
8599	Expr **exprs;
8600	unsigned numExprs;
8601	Expr *subExpr;
8602	SourceLocation LiteralLParenLoc, LiteralRParenLoc;
8603	if (ParenListExpr *PE = dyn_cast<ParenListExpr>(Val: E)) {
8604	LiteralLParenLoc = PE->getLParenLoc();
8605	LiteralRParenLoc = PE->getRParenLoc();
8606	exprs = PE->getExprs();
8607	numExprs = PE->getNumExprs();
8608	} else { // isa<ParenExpr> by assertion at function entrance
8609	LiteralLParenLoc = cast<ParenExpr>(Val: E)->getLParen();
8610	LiteralRParenLoc = cast<ParenExpr>(Val: E)->getRParen();
8611	subExpr = cast<ParenExpr>(Val: E)->getSubExpr();
8612	exprs = &subExpr;
8613	numExprs = 1;
8614	}
8615
8616	QualType Ty = TInfo->getType();
8617	assert(Ty->isVectorType() && "Expected vector type");
8618
8619	SmallVector<Expr *, 8> initExprs;
8620	const VectorType *VTy = Ty->castAs<VectorType>();
8621	unsigned numElems = VTy->getNumElements();
8622
8623	// '(...)' form of vector initialization in AltiVec: the number of
8624	// initializers must be one or must match the size of the vector.
8625	// If a single value is specified in the initializer then it will be
8626	// replicated to all the components of the vector
8627	if (CheckAltivecInitFromScalar(R: E->getSourceRange(), VecTy: Ty,
8628	SrcTy: VTy->getElementType()))
8629	return ExprError();
8630	if (ShouldSplatAltivecScalarInCast(VecTy: VTy)) {
8631	// The number of initializers must be one or must match the size of the
8632	// vector. If a single value is specified in the initializer then it will
8633	// be replicated to all the components of the vector
8634	if (numExprs == 1) {
8635	QualType ElemTy = VTy->getElementType();
8636	ExprResult Literal = DefaultLvalueConversion(E: exprs[0]);
8637	if (Literal.isInvalid())
8638	return ExprError();
8639	Literal = ImpCastExprToType(E: Literal.get(), Type: ElemTy,
8640	CK: PrepareScalarCast(Src&: Literal, DestTy: ElemTy));
8641	return BuildCStyleCastExpr(LParenLoc, Ty: TInfo, RParenLoc, Op: Literal.get());
8642	}
8643	else if (numExprs < numElems) {
8644	Diag(E->getExprLoc(),
8645	diag::err_incorrect_number_of_vector_initializers);
8646	return ExprError();
8647	}
8648	else
8649	initExprs.append(in_start: exprs, in_end: exprs + numExprs);
8650	}
8651	else {
8652	// For OpenCL, when the number of initializers is a single value,
8653	// it will be replicated to all components of the vector.
8654	if (getLangOpts().OpenCL && VTy->getVectorKind() == VectorKind::Generic &&
8655	numExprs == 1) {
8656	QualType ElemTy = VTy->getElementType();
8657	ExprResult Literal = DefaultLvalueConversion(E: exprs[0]);
8658	if (Literal.isInvalid())
8659	return ExprError();
8660	Literal = ImpCastExprToType(E: Literal.get(), Type: ElemTy,
8661	CK: PrepareScalarCast(Src&: Literal, DestTy: ElemTy));
8662	return BuildCStyleCastExpr(LParenLoc, Ty: TInfo, RParenLoc, Op: Literal.get());
8663	}
8664
8665	initExprs.append(in_start: exprs, in_end: exprs + numExprs);
8666	}
8667	// FIXME: This means that pretty-printing the final AST will produce curly
8668	// braces instead of the original commas.
8669	InitListExpr *initE = new (Context) InitListExpr(Context, LiteralLParenLoc,
8670	initExprs, LiteralRParenLoc);
8671	initE->setType(Ty);
8672	return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, initE);
8673	}
8674
8675	/// This is not an AltiVec-style cast or or C++ direct-initialization, so turn
8676	/// the ParenListExpr into a sequence of comma binary operators.
8677	ExprResult
8678	Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *OrigExpr) {
8679	ParenListExpr *E = dyn_cast<ParenListExpr>(Val: OrigExpr);
8680	if (!E)
8681	return OrigExpr;
8682
8683	ExprResult Result(E->getExpr(Init: 0));
8684
8685	for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i)
8686	Result = ActOnBinOp(S, TokLoc: E->getExprLoc(), Kind: tok::comma, LHSExpr: Result.get(),
8687	RHSExpr: E->getExpr(Init: i));
8688
8689	if (Result.isInvalid()) return ExprError();
8690
8691	return ActOnParenExpr(L: E->getLParenLoc(), R: E->getRParenLoc(), E: Result.get());
8692	}
8693
8694	ExprResult Sema::ActOnParenListExpr(SourceLocation L,
8695	SourceLocation R,
8696	MultiExprArg Val) {
8697	return ParenListExpr::Create(Ctx: Context, LParenLoc: L, Exprs: Val, RParenLoc: R);
8698	}
8699
8700	/// Emit a specialized diagnostic when one expression is a null pointer
8701	/// constant and the other is not a pointer. Returns true if a diagnostic is
8702	/// emitted.
8703	bool Sema::DiagnoseConditionalForNull(const Expr *LHSExpr, const Expr *RHSExpr,
8704	SourceLocation QuestionLoc) {
8705	const Expr *NullExpr = LHSExpr;
8706	const Expr *NonPointerExpr = RHSExpr;
8707	Expr::NullPointerConstantKind NullKind =
8708	NullExpr->isNullPointerConstant(Ctx&: Context,
8709	NPC: Expr::NPC_ValueDependentIsNotNull);
8710
8711	if (NullKind == Expr::NPCK_NotNull) {
8712	NullExpr = RHSExpr;
8713	NonPointerExpr = LHSExpr;
8714	NullKind =
8715	NullExpr->isNullPointerConstant(Ctx&: Context,
8716	NPC: Expr::NPC_ValueDependentIsNotNull);
8717	}
8718
8719	if (NullKind == Expr::NPCK_NotNull)
8720	return false;
8721
8722	if (NullKind == Expr::NPCK_ZeroExpression)
8723	return false;
8724
8725	if (NullKind == Expr::NPCK_ZeroLiteral) {
8726	// In this case, check to make sure that we got here from a "NULL"
8727	// string in the source code.
8728	NullExpr = NullExpr->IgnoreParenImpCasts();
8729	SourceLocation loc = NullExpr->getExprLoc();
8730	if (!findMacroSpelling(loc, name: "NULL"))
8731	return false;
8732	}
8733
8734	int DiagType = (NullKind == Expr::NPCK_CXX11_nullptr);
8735	Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands_null)
8736	<< NonPointerExpr->getType() << DiagType
8737	<< NonPointerExpr->getSourceRange();
8738	return true;
8739	}
8740
8741	/// Return false if the condition expression is valid, true otherwise.
8742	static bool checkCondition(Sema &S, const Expr *Cond,
8743	SourceLocation QuestionLoc) {
8744	QualType CondTy = Cond->getType();
8745
8746	// OpenCL v1.1 s6.3.i says the condition cannot be a floating point type.
8747	if (S.getLangOpts().OpenCL && CondTy->isFloatingType()) {
8748	S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_nonfloat)
8749	<< CondTy << Cond->getSourceRange();
8750	return true;
8751	}
8752
8753	// C99 6.5.15p2
8754	if (CondTy->isScalarType()) return false;
8755
8756	S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_scalar)
8757	<< CondTy << Cond->getSourceRange();
8758	return true;
8759	}
8760
8761	/// Return false if the NullExpr can be promoted to PointerTy,
8762	/// true otherwise.
8763	static bool checkConditionalNullPointer(Sema &S, ExprResult &NullExpr,
8764	QualType PointerTy) {
8765	if ((!PointerTy->isAnyPointerType() && !PointerTy->isBlockPointerType()) ||
8766	!NullExpr.get()->isNullPointerConstant(Ctx&: S.Context,
8767	NPC: Expr::NPC_ValueDependentIsNull))
8768	return true;
8769
8770	NullExpr = S.ImpCastExprToType(E: NullExpr.get(), Type: PointerTy, CK: CK_NullToPointer);
8771	return false;
8772	}
8773
8774	/// Checks compatibility between two pointers and return the resulting
8775	/// type.
8776	static QualType checkConditionalPointerCompatibility(Sema &S, ExprResult &LHS,
8777	ExprResult &RHS,
8778	SourceLocation Loc) {
8779	QualType LHSTy = LHS.get()->getType();
8780	QualType RHSTy = RHS.get()->getType();
8781
8782	if (S.Context.hasSameType(T1: LHSTy, T2: RHSTy)) {
8783	// Two identical pointers types are always compatible.
8784	return S.Context.getCommonSugaredType(X: LHSTy, Y: RHSTy);
8785	}
8786
8787	QualType lhptee, rhptee;
8788
8789	// Get the pointee types.
8790	bool IsBlockPointer = false;
8791	if (const BlockPointerType *LHSBTy = LHSTy->getAs<BlockPointerType>()) {
8792	lhptee = LHSBTy->getPointeeType();
8793	rhptee = RHSTy->castAs<BlockPointerType>()->getPointeeType();
8794	IsBlockPointer = true;
8795	} else {
8796	lhptee = LHSTy->castAs<PointerType>()->getPointeeType();
8797	rhptee = RHSTy->castAs<PointerType>()->getPointeeType();
8798	}
8799
8800	// C99 6.5.15p6: If both operands are pointers to compatible types or to
8801	// differently qualified versions of compatible types, the result type is
8802	// a pointer to an appropriately qualified version of the composite
8803	// type.
8804
8805	// Only CVR-qualifiers exist in the standard, and the differently-qualified
8806	// clause doesn't make sense for our extensions. E.g. address space 2 should
8807	// be incompatible with address space 3: they may live on different devices or
8808	// anything.
8809	Qualifiers lhQual = lhptee.getQualifiers();
8810	Qualifiers rhQual = rhptee.getQualifiers();
8811
8812	LangAS ResultAddrSpace = LangAS::Default;
8813	LangAS LAddrSpace = lhQual.getAddressSpace();
8814	LangAS RAddrSpace = rhQual.getAddressSpace();
8815
8816	// OpenCL v1.1 s6.5 - Conversion between pointers to distinct address
8817	// spaces is disallowed.
8818	if (lhQual.isAddressSpaceSupersetOf(other: rhQual))
8819	ResultAddrSpace = LAddrSpace;
8820	else if (rhQual.isAddressSpaceSupersetOf(other: lhQual))
8821	ResultAddrSpace = RAddrSpace;
8822	else {
8823	S.Diag(Loc, diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
8824	<< LHSTy << RHSTy << 2 << LHS.get()->getSourceRange()
8825	<< RHS.get()->getSourceRange();
8826	return QualType();
8827	}
8828
8829	unsigned MergedCVRQual = lhQual.getCVRQualifiers() | rhQual.getCVRQualifiers();
8830	auto LHSCastKind = CK_BitCast, RHSCastKind = CK_BitCast;
8831	lhQual.removeCVRQualifiers();
8832	rhQual.removeCVRQualifiers();
8833
8834	// OpenCL v2.0 specification doesn't extend compatibility of type qualifiers
8835	// (C99 6.7.3) for address spaces. We assume that the check should behave in
8836	// the same manner as it's defined for CVR qualifiers, so for OpenCL two
8837	// qual types are compatible iff
8838	// * corresponded types are compatible
8839	// * CVR qualifiers are equal
8840	// * address spaces are equal
8841	// Thus for conditional operator we merge CVR and address space unqualified
8842	// pointees and if there is a composite type we return a pointer to it with
8843	// merged qualifiers.
8844	LHSCastKind =
8845	LAddrSpace == ResultAddrSpace ? CK_BitCast : CK_AddressSpaceConversion;
8846	RHSCastKind =
8847	RAddrSpace == ResultAddrSpace ? CK_BitCast : CK_AddressSpaceConversion;
8848	lhQual.removeAddressSpace();
8849	rhQual.removeAddressSpace();
8850
8851	lhptee = S.Context.getQualifiedType(T: lhptee.getUnqualifiedType(), Qs: lhQual);
8852	rhptee = S.Context.getQualifiedType(T: rhptee.getUnqualifiedType(), Qs: rhQual);
8853
8854	QualType CompositeTy = S.Context.mergeTypes(
8855	lhptee, rhptee, /*OfBlockPointer=*/false, /*Unqualified=*/false,
8856	/*BlockReturnType=*/false, /*IsConditionalOperator=*/true);
8857
8858	if (CompositeTy.isNull()) {
8859	// In this situation, we assume void* type. No especially good
8860	// reason, but this is what gcc does, and we do have to pick
8861	// to get a consistent AST.
8862	QualType incompatTy;
8863	incompatTy = S.Context.getPointerType(
8864	S.Context.getAddrSpaceQualType(T: S.Context.VoidTy, AddressSpace: ResultAddrSpace));
8865	LHS = S.ImpCastExprToType(E: LHS.get(), Type: incompatTy, CK: LHSCastKind);
8866	RHS = S.ImpCastExprToType(E: RHS.get(), Type: incompatTy, CK: RHSCastKind);
8867
8868	// FIXME: For OpenCL the warning emission and cast to void* leaves a room
8869	// for casts between types with incompatible address space qualifiers.
8870	// For the following code the compiler produces casts between global and
8871	// local address spaces of the corresponded innermost pointees:
8872	// local int *global *a;
8873	// global int *global *b;
8874	// a = (0 ? a : b); // see C99 6.5.16.1.p1.
8875	S.Diag(Loc, diag::ext_typecheck_cond_incompatible_pointers)
8876	<< LHSTy << RHSTy << LHS.get()->getSourceRange()
8877	<< RHS.get()->getSourceRange();
8878
8879	return incompatTy;
8880	}
8881
8882	// The pointer types are compatible.
8883	// In case of OpenCL ResultTy should have the address space qualifier
8884	// which is a superset of address spaces of both the 2nd and the 3rd
8885	// operands of the conditional operator.
8886	QualType ResultTy = [&, ResultAddrSpace]() {
8887	if (S.getLangOpts().OpenCL) {
8888	Qualifiers CompositeQuals = CompositeTy.getQualifiers();
8889	CompositeQuals.setAddressSpace(ResultAddrSpace);
8890	return S.Context
8891	.getQualifiedType(T: CompositeTy.getUnqualifiedType(), Qs: CompositeQuals)
8892	.withCVRQualifiers(CVR: MergedCVRQual);
8893	}
8894	return CompositeTy.withCVRQualifiers(CVR: MergedCVRQual);
8895	}();
8896	if (IsBlockPointer)
8897	ResultTy = S.Context.getBlockPointerType(T: ResultTy);
8898	else
8899	ResultTy = S.Context.getPointerType(T: ResultTy);
8900
8901	LHS = S.ImpCastExprToType(E: LHS.get(), Type: ResultTy, CK: LHSCastKind);
8902	RHS = S.ImpCastExprToType(E: RHS.get(), Type: ResultTy, CK: RHSCastKind);
8903	return ResultTy;
8904	}
8905
8906	/// Return the resulting type when the operands are both block pointers.
8907	static QualType checkConditionalBlockPointerCompatibility(Sema &S,
8908	ExprResult &LHS,
8909	ExprResult &RHS,
8910	SourceLocation Loc) {
8911	QualType LHSTy = LHS.get()->getType();
8912	QualType RHSTy = RHS.get()->getType();
8913
8914	if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) {
8915	if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) {
8916	QualType destType = S.Context.getPointerType(S.Context.VoidTy);
8917	LHS = S.ImpCastExprToType(E: LHS.get(), Type: destType, CK: CK_BitCast);
8918	RHS = S.ImpCastExprToType(E: RHS.get(), Type: destType, CK: CK_BitCast);
8919	return destType;
8920	}
8921	S.Diag(Loc, diag::err_typecheck_cond_incompatible_operands)
8922	<< LHSTy << RHSTy << LHS.get()->getSourceRange()
8923	<< RHS.get()->getSourceRange();
8924	return QualType();
8925	}
8926
8927	// We have 2 block pointer types.
8928	return checkConditionalPointerCompatibility(S, LHS, RHS, Loc);
8929	}
8930
8931	/// Return the resulting type when the operands are both pointers.
8932	static QualType
8933	checkConditionalObjectPointersCompatibility(Sema &S, ExprResult &LHS,
8934	ExprResult &RHS,
8935	SourceLocation Loc) {
8936	// get the pointer types
8937	QualType LHSTy = LHS.get()->getType();
8938	QualType RHSTy = RHS.get()->getType();
8939
8940	// get the "pointed to" types
8941	QualType lhptee = LHSTy->castAs<PointerType>()->getPointeeType();
8942	QualType rhptee = RHSTy->castAs<PointerType>()->getPointeeType();
8943
8944	// ignore qualifiers on void (C99 6.5.15p3, clause 6)
8945	if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) {
8946	// Figure out necessary qualifiers (C99 6.5.15p6)
8947	QualType destPointee
8948	= S.Context.getQualifiedType(T: lhptee, Qs: rhptee.getQualifiers());
8949	QualType destType = S.Context.getPointerType(T: destPointee);
8950	// Add qualifiers if necessary.
8951	LHS = S.ImpCastExprToType(E: LHS.get(), Type: destType, CK: CK_NoOp);
8952	// Promote to void*.
8953	RHS = S.ImpCastExprToType(E: RHS.get(), Type: destType, CK: CK_BitCast);
8954	return destType;
8955	}
8956	if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) {
8957	QualType destPointee
8958	= S.Context.getQualifiedType(T: rhptee, Qs: lhptee.getQualifiers());
8959	QualType destType = S.Context.getPointerType(T: destPointee);
8960	// Add qualifiers if necessary.
8961	RHS = S.ImpCastExprToType(E: RHS.get(), Type: destType, CK: CK_NoOp);
8962	// Promote to void*.
8963	LHS = S.ImpCastExprToType(E: LHS.get(), Type: destType, CK: CK_BitCast);
8964	return destType;
8965	}
8966
8967	return checkConditionalPointerCompatibility(S, LHS, RHS, Loc);
8968	}
8969
8970	/// Return false if the first expression is not an integer and the second
8971	/// expression is not a pointer, true otherwise.
8972	static bool checkPointerIntegerMismatch(Sema &S, ExprResult &Int,
8973	Expr* PointerExpr, SourceLocation Loc,
8974	bool IsIntFirstExpr) {
8975	if (!PointerExpr->getType()->isPointerType() ||
8976	!Int.get()->getType()->isIntegerType())
8977	return false;
8978
8979	Expr *Expr1 = IsIntFirstExpr ? Int.get() : PointerExpr;
8980	Expr *Expr2 = IsIntFirstExpr ? PointerExpr : Int.get();
8981
8982	S.Diag(Loc, diag::ext_typecheck_cond_pointer_integer_mismatch)
8983	<< Expr1->getType() << Expr2->getType()
8984	<< Expr1->getSourceRange() << Expr2->getSourceRange();
8985	Int = S.ImpCastExprToType(E: Int.get(), Type: PointerExpr->getType(),
8986	CK: CK_IntegralToPointer);
8987	return true;
8988	}
8989
8990	/// Simple conversion between integer and floating point types.
8991	///
8992	/// Used when handling the OpenCL conditional operator where the
8993	/// condition is a vector while the other operands are scalar.
8994	///
8995	/// OpenCL v1.1 s6.3.i and s6.11.6 together require that the scalar
8996	/// types are either integer or floating type. Between the two
8997	/// operands, the type with the higher rank is defined as the "result
8998	/// type". The other operand needs to be promoted to the same type. No
8999	/// other type promotion is allowed. We cannot use
9000	/// UsualArithmeticConversions() for this purpose, since it always
9001	/// promotes promotable types.
9002	static QualType OpenCLArithmeticConversions(Sema &S, ExprResult &LHS,
9003	ExprResult &RHS,
9004	SourceLocation QuestionLoc) {
9005	LHS = S.DefaultFunctionArrayLvalueConversion(E: LHS.get());
9006	if (LHS.isInvalid())
9007	return QualType();
9008	RHS = S.DefaultFunctionArrayLvalueConversion(E: RHS.get());
9009	if (RHS.isInvalid())
9010	return QualType();
9011
9012	// For conversion purposes, we ignore any qualifiers.
9013	// For example, "const float" and "float" are equivalent.
9014	QualType LHSType =
9015	S.Context.getCanonicalType(T: LHS.get()->getType()).getUnqualifiedType();
9016	QualType RHSType =
9017	S.Context.getCanonicalType(T: RHS.get()->getType()).getUnqualifiedType();
9018
9019	if (!LHSType->isIntegerType() && !LHSType->isRealFloatingType()) {
9020	S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_int_float)
9021	<< LHSType << LHS.get()->getSourceRange();
9022	return QualType();
9023	}
9024
9025	if (!RHSType->isIntegerType() && !RHSType->isRealFloatingType()) {
9026	S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_int_float)
9027	<< RHSType << RHS.get()->getSourceRange();
9028	return QualType();
9029	}
9030
9031	// If both types are identical, no conversion is needed.
9032	if (LHSType == RHSType)
9033	return LHSType;
9034
9035	// Now handle "real" floating types (i.e. float, double, long double).
9036	if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType())
9037	return handleFloatConversion(S, LHS, RHS, LHSType, RHSType,
9038	/*IsCompAssign = */ false);
9039
9040	// Finally, we have two differing integer types.
9041	return handleIntegerConversion<doIntegralCast, doIntegralCast>
9042	(S, LHS, RHS, LHSType, RHSType, /*IsCompAssign = */ false);
9043	}
9044
9045	/// Convert scalar operands to a vector that matches the
9046	/// condition in length.
9047	///
9048	/// Used when handling the OpenCL conditional operator where the
9049	/// condition is a vector while the other operands are scalar.
9050	///
9051	/// We first compute the "result type" for the scalar operands
9052	/// according to OpenCL v1.1 s6.3.i. Both operands are then converted
9053	/// into a vector of that type where the length matches the condition
9054	/// vector type. s6.11.6 requires that the element types of the result
9055	/// and the condition must have the same number of bits.
9056	static QualType
9057	OpenCLConvertScalarsToVectors(Sema &S, ExprResult &LHS, ExprResult &RHS,
9058	QualType CondTy, SourceLocation QuestionLoc) {
9059	QualType ResTy = OpenCLArithmeticConversions(S, LHS, RHS, QuestionLoc);
9060	if (ResTy.isNull()) return QualType();
9061
9062	const VectorType *CV = CondTy->getAs<VectorType>();
9063	assert(CV);
9064
9065	// Determine the vector result type
9066	unsigned NumElements = CV->getNumElements();
9067	QualType VectorTy = S.Context.getExtVectorType(VectorType: ResTy, NumElts: NumElements);
9068
9069	// Ensure that all types have the same number of bits
9070	if (S.Context.getTypeSize(T: CV->getElementType())
9071	!= S.Context.getTypeSize(T: ResTy)) {
9072	// Since VectorTy is created internally, it does not pretty print
9073	// with an OpenCL name. Instead, we just print a description.
9074	std::string EleTyName = ResTy.getUnqualifiedType().getAsString();
9075	SmallString<64> Str;
9076	llvm::raw_svector_ostream OS(Str);
9077	OS << "(vector of " << NumElements << " '" << EleTyName << "' values)";
9078	S.Diag(QuestionLoc, diag::err_conditional_vector_element_size)
9079	<< CondTy << OS.str();
9080	return QualType();
9081	}
9082
9083	// Convert operands to the vector result type
9084	LHS = S.ImpCastExprToType(E: LHS.get(), Type: VectorTy, CK: CK_VectorSplat);
9085	RHS = S.ImpCastExprToType(E: RHS.get(), Type: VectorTy, CK: CK_VectorSplat);
9086
9087	return VectorTy;
9088	}
9089
9090	/// Return false if this is a valid OpenCL condition vector
9091	static bool checkOpenCLConditionVector(Sema &S, Expr *Cond,
9092	SourceLocation QuestionLoc) {
9093	// OpenCL v1.1 s6.11.6 says the elements of the vector must be of
9094	// integral type.
9095	const VectorType *CondTy = Cond->getType()->getAs<VectorType>();
9096	assert(CondTy);
9097	QualType EleTy = CondTy->getElementType();
9098	if (EleTy->isIntegerType()) return false;
9099
9100	S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_nonfloat)
9101	<< Cond->getType() << Cond->getSourceRange();
9102	return true;
9103	}
9104
9105	/// Return false if the vector condition type and the vector
9106	/// result type are compatible.
9107	///
9108	/// OpenCL v1.1 s6.11.6 requires that both vector types have the same
9109	/// number of elements, and their element types have the same number
9110	/// of bits.
9111	static bool checkVectorResult(Sema &S, QualType CondTy, QualType VecResTy,
9112	SourceLocation QuestionLoc) {
9113	const VectorType *CV = CondTy->getAs<VectorType>();
9114	const VectorType *RV = VecResTy->getAs<VectorType>();
9115	assert(CV && RV);
9116
9117	if (CV->getNumElements() != RV->getNumElements()) {
9118	S.Diag(QuestionLoc, diag::err_conditional_vector_size)
9119	<< CondTy << VecResTy;
9120	return true;
9121	}
9122
9123	QualType CVE = CV->getElementType();
9124	QualType RVE = RV->getElementType();
9125
9126	if (S.Context.getTypeSize(T: CVE) != S.Context.getTypeSize(T: RVE)) {
9127	S.Diag(QuestionLoc, diag::err_conditional_vector_element_size)
9128	<< CondTy << VecResTy;
9129	return true;
9130	}
9131
9132	return false;
9133	}
9134
9135	/// Return the resulting type for the conditional operator in
9136	/// OpenCL (aka "ternary selection operator", OpenCL v1.1
9137	/// s6.3.i) when the condition is a vector type.
9138	static QualType
9139	OpenCLCheckVectorConditional(Sema &S, ExprResult &Cond,
9140	ExprResult &LHS, ExprResult &RHS,
9141	SourceLocation QuestionLoc) {
9142	Cond = S.DefaultFunctionArrayLvalueConversion(E: Cond.get());
9143	if (Cond.isInvalid())
9144	return QualType();
9145	QualType CondTy = Cond.get()->getType();
9146
9147	if (checkOpenCLConditionVector(S, Cond: Cond.get(), QuestionLoc))
9148	return QualType();
9149
9150	// If either operand is a vector then find the vector type of the
9151	// result as specified in OpenCL v1.1 s6.3.i.
9152	if (LHS.get()->getType()->isVectorType() ||
9153	RHS.get()->getType()->isVectorType()) {
9154	bool IsBoolVecLang =
9155	!S.getLangOpts().OpenCL && !S.getLangOpts().OpenCLCPlusPlus;
9156	QualType VecResTy =
9157	S.CheckVectorOperands(LHS, RHS, Loc: QuestionLoc,
9158	/*isCompAssign*/ IsCompAssign: false,
9159	/*AllowBothBool*/ true,
9160	/*AllowBoolConversions*/ AllowBoolConversion: false,
9161	/*AllowBooleanOperation*/ AllowBoolOperation: IsBoolVecLang,
9162	/*ReportInvalid*/ true);
9163	if (VecResTy.isNull())
9164	return QualType();
9165	// The result type must match the condition type as specified in
9166	// OpenCL v1.1 s6.11.6.
9167	if (checkVectorResult(S, CondTy, VecResTy, QuestionLoc))
9168	return QualType();
9169	return VecResTy;
9170	}
9171
9172	// Both operands are scalar.
9173	return OpenCLConvertScalarsToVectors(S, LHS, RHS, CondTy, QuestionLoc);
9174	}
9175
9176	/// Return true if the Expr is block type
9177	static bool checkBlockType(Sema &S, const Expr *E) {
9178	if (const CallExpr *CE = dyn_cast<CallExpr>(Val: E)) {
9179	QualType Ty = CE->getCallee()->getType();
9180	if (Ty->isBlockPointerType()) {
9181	S.Diag(E->getExprLoc(), diag::err_opencl_ternary_with_block);
9182	return true;
9183	}
9184	}
9185	return false;
9186	}
9187
9188	/// Note that LHS is not null here, even if this is the gnu "x ?: y" extension.
9189	/// In that case, LHS = cond.
9190	/// C99 6.5.15
9191	QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
9192	ExprResult &RHS, ExprValueKind &VK,
9193	ExprObjectKind &OK,
9194	SourceLocation QuestionLoc) {
9195
9196	ExprResult LHSResult = CheckPlaceholderExpr(E: LHS.get());
9197	if (!LHSResult.isUsable()) return QualType();
9198	LHS = LHSResult;
9199
9200	ExprResult RHSResult = CheckPlaceholderExpr(E: RHS.get());
9201	if (!RHSResult.isUsable()) return QualType();
9202	RHS = RHSResult;
9203
9204	// C++ is sufficiently different to merit its own checker.
9205	if (getLangOpts().CPlusPlus)
9206	return CXXCheckConditionalOperands(cond&: Cond, lhs&: LHS, rhs&: RHS, VK, OK, questionLoc: QuestionLoc);
9207
9208	VK = VK_PRValue;
9209	OK = OK_Ordinary;
9210
9211	if (Context.isDependenceAllowed() &&
9212	(Cond.get()->isTypeDependent() || LHS.get()->isTypeDependent() ||
9213	RHS.get()->isTypeDependent())) {
9214	assert(!getLangOpts().CPlusPlus);
9215	assert((Cond.get()->containsErrors() || LHS.get()->containsErrors() ||
9216	RHS.get()->containsErrors()) &&
9217	"should only occur in error-recovery path.");
9218	return Context.DependentTy;
9219	}
9220
9221	// The OpenCL operator with a vector condition is sufficiently
9222	// different to merit its own checker.
9223	if ((getLangOpts().OpenCL && Cond.get()->getType()->isVectorType()) ||
9224	Cond.get()->getType()->isExtVectorType())
9225	return OpenCLCheckVectorConditional(S&: *this, Cond, LHS, RHS, QuestionLoc);
9226
9227	// First, check the condition.
9228	Cond = UsualUnaryConversions(E: Cond.get());
9229	if (Cond.isInvalid())
9230	return QualType();
9231	if (checkCondition(S&: *this, Cond: Cond.get(), QuestionLoc))
9232	return QualType();
9233
9234	// Handle vectors.
9235	if (LHS.get()->getType()->isVectorType() ||
9236	RHS.get()->getType()->isVectorType())
9237	return CheckVectorOperands(LHS, RHS, Loc: QuestionLoc, /*isCompAssign*/ IsCompAssign: false,
9238	/*AllowBothBool*/ true,
9239	/*AllowBoolConversions*/ AllowBoolConversion: false,
9240	/*AllowBooleanOperation*/ AllowBoolOperation: false,
9241	/*ReportInvalid*/ true);
9242
9243	QualType ResTy =
9244	UsualArithmeticConversions(LHS, RHS, Loc: QuestionLoc, ACK: ACK_Conditional);
9245	if (LHS.isInvalid() || RHS.isInvalid())
9246	return QualType();
9247
9248	// WebAssembly tables are not allowed as conditional LHS or RHS.
9249	QualType LHSTy = LHS.get()->getType();
9250	QualType RHSTy = RHS.get()->getType();
9251	if (LHSTy->isWebAssemblyTableType() || RHSTy->isWebAssemblyTableType()) {
9252	Diag(QuestionLoc, diag::err_wasm_table_conditional_expression)
9253	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9254	return QualType();
9255	}
9256
9257	// Diagnose attempts to convert between __ibm128, __float128 and long double
9258	// where such conversions currently can't be handled.
9259	if (unsupportedTypeConversion(S: *this, LHSType: LHSTy, RHSType: RHSTy)) {
9260	Diag(QuestionLoc,
9261	diag::err_typecheck_cond_incompatible_operands) << LHSTy << RHSTy
9262	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9263	return QualType();
9264	}
9265
9266	// OpenCL v2.0 s6.12.5 - Blocks cannot be used as expressions of the ternary
9267	// selection operator (?:).
9268	if (getLangOpts().OpenCL &&
9269	((int)checkBlockType(S&: *this, E: LHS.get()) | (int)checkBlockType(S&: *this, E: RHS.get()))) {
9270	return QualType();
9271	}
9272
9273	// If both operands have arithmetic type, do the usual arithmetic conversions
9274	// to find a common type: C99 6.5.15p3,5.
9275	if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) {
9276	// Disallow invalid arithmetic conversions, such as those between bit-
9277	// precise integers types of different sizes, or between a bit-precise
9278	// integer and another type.
9279	if (ResTy.isNull() && (LHSTy->isBitIntType() || RHSTy->isBitIntType())) {
9280	Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
9281	<< LHSTy << RHSTy << LHS.get()->getSourceRange()
9282	<< RHS.get()->getSourceRange();
9283	return QualType();
9284	}
9285
9286	LHS = ImpCastExprToType(E: LHS.get(), Type: ResTy, CK: PrepareScalarCast(Src&: LHS, DestTy: ResTy));
9287	RHS = ImpCastExprToType(E: RHS.get(), Type: ResTy, CK: PrepareScalarCast(Src&: RHS, DestTy: ResTy));
9288
9289	return ResTy;
9290	}
9291
9292	// If both operands are the same structure or union type, the result is that
9293	// type.
9294	if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3
9295	if (const RecordType *RHSRT = RHSTy->getAs<RecordType>())
9296	if (LHSRT->getDecl() == RHSRT->getDecl())
9297	// "If both the operands have structure or union type, the result has
9298	// that type." This implies that CV qualifiers are dropped.
9299	return Context.getCommonSugaredType(X: LHSTy.getUnqualifiedType(),
9300	Y: RHSTy.getUnqualifiedType());
9301	// FIXME: Type of conditional expression must be complete in C mode.
9302	}
9303
9304	// C99 6.5.15p5: "If both operands have void type, the result has void type."
9305	// The following || allows only one side to be void (a GCC-ism).
9306	if (LHSTy->isVoidType() || RHSTy->isVoidType()) {
9307	QualType ResTy;
9308	if (LHSTy->isVoidType() && RHSTy->isVoidType()) {
9309	ResTy = Context.getCommonSugaredType(X: LHSTy, Y: RHSTy);
9310	} else if (RHSTy->isVoidType()) {
9311	ResTy = RHSTy;
9312	Diag(RHS.get()->getBeginLoc(), diag::ext_typecheck_cond_one_void)
9313	<< RHS.get()->getSourceRange();
9314	} else {
9315	ResTy = LHSTy;
9316	Diag(LHS.get()->getBeginLoc(), diag::ext_typecheck_cond_one_void)
9317	<< LHS.get()->getSourceRange();
9318	}
9319	LHS = ImpCastExprToType(E: LHS.get(), Type: ResTy, CK: CK_ToVoid);
9320	RHS = ImpCastExprToType(E: RHS.get(), Type: ResTy, CK: CK_ToVoid);
9321	return ResTy;
9322	}
9323
9324	// C23 6.5.15p7:
9325	// ... if both the second and third operands have nullptr_t type, the
9326	// result also has that type.
9327	if (LHSTy->isNullPtrType() && Context.hasSameType(T1: LHSTy, T2: RHSTy))
9328	return ResTy;
9329
9330	// C99 6.5.15p6 - "if one operand is a null pointer constant, the result has
9331	// the type of the other operand."
9332	if (!checkConditionalNullPointer(S&: *this, NullExpr&: RHS, PointerTy: LHSTy)) return LHSTy;
9333	if (!checkConditionalNullPointer(S&: *this, NullExpr&: LHS, PointerTy: RHSTy)) return RHSTy;
9334
9335	// All objective-c pointer type analysis is done here.
9336	QualType compositeType = FindCompositeObjCPointerType(LHS, RHS,
9337	QuestionLoc);
9338	if (LHS.isInvalid() || RHS.isInvalid())
9339	return QualType();
9340	if (!compositeType.isNull())
9341	return compositeType;
9342
9343
9344	// Handle block pointer types.
9345	if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType())
9346	return checkConditionalBlockPointerCompatibility(S&: *this, LHS, RHS,
9347	Loc: QuestionLoc);
9348
9349	// Check constraints for C object pointers types (C99 6.5.15p3,6).
9350	if (LHSTy->isPointerType() && RHSTy->isPointerType())
9351	return checkConditionalObjectPointersCompatibility(S&: *this, LHS, RHS,
9352	Loc: QuestionLoc);
9353
9354	// GCC compatibility: soften pointer/integer mismatch. Note that
9355	// null pointers have been filtered out by this point.
9356	if (checkPointerIntegerMismatch(S&: *this, Int&: LHS, PointerExpr: RHS.get(), Loc: QuestionLoc,
9357	/*IsIntFirstExpr=*/true))
9358	return RHSTy;
9359	if (checkPointerIntegerMismatch(S&: *this, Int&: RHS, PointerExpr: LHS.get(), Loc: QuestionLoc,
9360	/*IsIntFirstExpr=*/false))
9361	return LHSTy;
9362
9363	// Emit a better diagnostic if one of the expressions is a null pointer
9364	// constant and the other is not a pointer type. In this case, the user most
9365	// likely forgot to take the address of the other expression.
9366	if (DiagnoseConditionalForNull(LHSExpr: LHS.get(), RHSExpr: RHS.get(), QuestionLoc))
9367	return QualType();
9368
9369	// Finally, if the LHS and RHS types are canonically the same type, we can
9370	// use the common sugared type.
9371	if (Context.hasSameType(T1: LHSTy, T2: RHSTy))
9372	return Context.getCommonSugaredType(X: LHSTy, Y: RHSTy);
9373
9374	// Otherwise, the operands are not compatible.
9375	Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
9376	<< LHSTy << RHSTy << LHS.get()->getSourceRange()
9377	<< RHS.get()->getSourceRange();
9378	return QualType();
9379	}
9380
9381	/// FindCompositeObjCPointerType - Helper method to find composite type of
9382	/// two objective-c pointer types of the two input expressions.
9383	QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS,
9384	SourceLocation QuestionLoc) {
9385	QualType LHSTy = LHS.get()->getType();
9386	QualType RHSTy = RHS.get()->getType();
9387
9388	// Handle things like Class and struct objc_class*. Here we case the result
9389	// to the pseudo-builtin, because that will be implicitly cast back to the
9390	// redefinition type if an attempt is made to access its fields.
9391	if (LHSTy->isObjCClassType() &&
9392	(Context.hasSameType(T1: RHSTy, T2: Context.getObjCClassRedefinitionType()))) {
9393	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSTy, CK: CK_CPointerToObjCPointerCast);
9394	return LHSTy;
9395	}
9396	if (RHSTy->isObjCClassType() &&
9397	(Context.hasSameType(T1: LHSTy, T2: Context.getObjCClassRedefinitionType()))) {
9398	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSTy, CK: CK_CPointerToObjCPointerCast);
9399	return RHSTy;
9400	}
9401	// And the same for struct objc_object* / id
9402	if (LHSTy->isObjCIdType() &&
9403	(Context.hasSameType(T1: RHSTy, T2: Context.getObjCIdRedefinitionType()))) {
9404	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSTy, CK: CK_CPointerToObjCPointerCast);
9405	return LHSTy;
9406	}
9407	if (RHSTy->isObjCIdType() &&
9408	(Context.hasSameType(T1: LHSTy, T2: Context.getObjCIdRedefinitionType()))) {
9409	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSTy, CK: CK_CPointerToObjCPointerCast);
9410	return RHSTy;
9411	}
9412	// And the same for struct objc_selector* / SEL
9413	if (Context.isObjCSelType(T: LHSTy) &&
9414	(Context.hasSameType(T1: RHSTy, T2: Context.getObjCSelRedefinitionType()))) {
9415	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSTy, CK: CK_BitCast);
9416	return LHSTy;
9417	}
9418	if (Context.isObjCSelType(T: RHSTy) &&
9419	(Context.hasSameType(T1: LHSTy, T2: Context.getObjCSelRedefinitionType()))) {
9420	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSTy, CK: CK_BitCast);
9421	return RHSTy;
9422	}
9423	// Check constraints for Objective-C object pointers types.
9424	if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) {
9425
9426	if (Context.getCanonicalType(T: LHSTy) == Context.getCanonicalType(T: RHSTy)) {
9427	// Two identical object pointer types are always compatible.
9428	return LHSTy;
9429	}
9430	const ObjCObjectPointerType *LHSOPT = LHSTy->castAs<ObjCObjectPointerType>();
9431	const ObjCObjectPointerType *RHSOPT = RHSTy->castAs<ObjCObjectPointerType>();
9432	QualType compositeType = LHSTy;
9433
9434	// If both operands are interfaces and either operand can be
9435	// assigned to the other, use that type as the composite
9436	// type. This allows
9437	// xxx ? (A*) a : (B*) b
9438	// where B is a subclass of A.
9439	//
9440	// Additionally, as for assignment, if either type is 'id'
9441	// allow silent coercion. Finally, if the types are
9442	// incompatible then make sure to use 'id' as the composite
9443	// type so the result is acceptable for sending messages to.
9444
9445	// FIXME: Consider unifying with 'areComparableObjCPointerTypes'.
9446	// It could return the composite type.
9447	if (!(compositeType =
9448	Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) {
9449	// Nothing more to do.
9450	} else if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) {
9451	compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy;
9452	} else if (Context.canAssignObjCInterfaces(LHSOPT: RHSOPT, RHSOPT: LHSOPT)) {
9453	compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy;
9454	} else if ((LHSOPT->isObjCQualifiedIdType() ||
9455	RHSOPT->isObjCQualifiedIdType()) &&
9456	Context.ObjCQualifiedIdTypesAreCompatible(LHS: LHSOPT, RHS: RHSOPT,
9457	ForCompare: true)) {
9458	// Need to handle "id<xx>" explicitly.
9459	// GCC allows qualified id and any Objective-C type to devolve to
9460	// id. Currently localizing to here until clear this should be
9461	// part of ObjCQualifiedIdTypesAreCompatible.
9462	compositeType = Context.getObjCIdType();
9463	} else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) {
9464	compositeType = Context.getObjCIdType();
9465	} else {
9466	Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands)
9467	<< LHSTy << RHSTy
9468	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9469	QualType incompatTy = Context.getObjCIdType();
9470	LHS = ImpCastExprToType(E: LHS.get(), Type: incompatTy, CK: CK_BitCast);
9471	RHS = ImpCastExprToType(E: RHS.get(), Type: incompatTy, CK: CK_BitCast);
9472	return incompatTy;
9473	}
9474	// The object pointer types are compatible.
9475	LHS = ImpCastExprToType(E: LHS.get(), Type: compositeType, CK: CK_BitCast);
9476	RHS = ImpCastExprToType(E: RHS.get(), Type: compositeType, CK: CK_BitCast);
9477	return compositeType;
9478	}
9479	// Check Objective-C object pointer types and 'void *'
9480	if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) {
9481	if (getLangOpts().ObjCAutoRefCount) {
9482	// ARC forbids the implicit conversion of object pointers to 'void *',
9483	// so these types are not compatible.
9484	Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy
9485	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9486	LHS = RHS = true;
9487	return QualType();
9488	}
9489	QualType lhptee = LHSTy->castAs<PointerType>()->getPointeeType();
9490	QualType rhptee = RHSTy->castAs<ObjCObjectPointerType>()->getPointeeType();
9491	QualType destPointee
9492	= Context.getQualifiedType(T: lhptee, Qs: rhptee.getQualifiers());
9493	QualType destType = Context.getPointerType(T: destPointee);
9494	// Add qualifiers if necessary.
9495	LHS = ImpCastExprToType(E: LHS.get(), Type: destType, CK: CK_NoOp);
9496	// Promote to void*.
9497	RHS = ImpCastExprToType(E: RHS.get(), Type: destType, CK: CK_BitCast);
9498	return destType;
9499	}
9500	if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) {
9501	if (getLangOpts().ObjCAutoRefCount) {
9502	// ARC forbids the implicit conversion of object pointers to 'void *',
9503	// so these types are not compatible.
9504	Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy
9505	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9506	LHS = RHS = true;
9507	return QualType();
9508	}
9509	QualType lhptee = LHSTy->castAs<ObjCObjectPointerType>()->getPointeeType();
9510	QualType rhptee = RHSTy->castAs<PointerType>()->getPointeeType();
9511	QualType destPointee
9512	= Context.getQualifiedType(T: rhptee, Qs: lhptee.getQualifiers());
9513	QualType destType = Context.getPointerType(T: destPointee);
9514	// Add qualifiers if necessary.
9515	RHS = ImpCastExprToType(E: RHS.get(), Type: destType, CK: CK_NoOp);
9516	// Promote to void*.
9517	LHS = ImpCastExprToType(E: LHS.get(), Type: destType, CK: CK_BitCast);
9518	return destType;
9519	}
9520	return QualType();
9521	}
9522
9523	/// SuggestParentheses - Emit a note with a fixit hint that wraps
9524	/// ParenRange in parentheses.
9525	static void SuggestParentheses(Sema &Self, SourceLocation Loc,
9526	const PartialDiagnostic &Note,
9527	SourceRange ParenRange) {
9528	SourceLocation EndLoc = Self.getLocForEndOfToken(Loc: ParenRange.getEnd());
9529	if (ParenRange.getBegin().isFileID() && ParenRange.getEnd().isFileID() &&
9530	EndLoc.isValid()) {
9531	Self.Diag(Loc, PD: Note)
9532	<< FixItHint::CreateInsertion(InsertionLoc: ParenRange.getBegin(), Code: "(")
9533	<< FixItHint::CreateInsertion(InsertionLoc: EndLoc, Code: ")");
9534	} else {
9535	// We can't display the parentheses, so just show the bare note.
9536	Self.Diag(Loc, PD: Note) << ParenRange;
9537	}
9538	}
9539
9540	static bool IsArithmeticOp(BinaryOperatorKind Opc) {
9541	return BinaryOperator::isAdditiveOp(Opc) ||
9542	BinaryOperator::isMultiplicativeOp(Opc) ||
9543	BinaryOperator::isShiftOp(Opc) || Opc == BO_And || Opc == BO_Or;
9544	// This only checks for bitwise-or and bitwise-and, but not bitwise-xor and
9545	// not any of the logical operators. Bitwise-xor is commonly used as a
9546	// logical-xor because there is no logical-xor operator. The logical
9547	// operators, including uses of xor, have a high false positive rate for
9548	// precedence warnings.
9549	}
9550
9551	/// IsArithmeticBinaryExpr - Returns true if E is an arithmetic binary
9552	/// expression, either using a built-in or overloaded operator,
9553	/// and sets *OpCode to the opcode and *RHSExprs to the right-hand side
9554	/// expression.
9555	static bool IsArithmeticBinaryExpr(const Expr *E, BinaryOperatorKind *Opcode,
9556	const Expr **RHSExprs) {
9557	// Don't strip parenthesis: we should not warn if E is in parenthesis.
9558	E = E->IgnoreImpCasts();
9559	E = E->IgnoreConversionOperatorSingleStep();
9560	E = E->IgnoreImpCasts();
9561	if (const auto *MTE = dyn_cast<MaterializeTemporaryExpr>(Val: E)) {
9562	E = MTE->getSubExpr();
9563	E = E->IgnoreImpCasts();
9564	}
9565
9566	// Built-in binary operator.
9567	if (const auto *OP = dyn_cast<BinaryOperator>(Val: E);
9568	OP && IsArithmeticOp(Opc: OP->getOpcode())) {
9569	*Opcode = OP->getOpcode();
9570	*RHSExprs = OP->getRHS();
9571	return true;
9572	}
9573
9574	// Overloaded operator.
9575	if (const auto *Call = dyn_cast<CXXOperatorCallExpr>(Val: E)) {
9576	if (Call->getNumArgs() != 2)
9577	return false;
9578
9579	// Make sure this is really a binary operator that is safe to pass into
9580	// BinaryOperator::getOverloadedOpcode(), e.g. it's not a subscript op.
9581	OverloadedOperatorKind OO = Call->getOperator();
9582	if (OO < OO_Plus || OO > OO_Arrow ||
9583	OO == OO_PlusPlus || OO == OO_MinusMinus)
9584	return false;
9585
9586	BinaryOperatorKind OpKind = BinaryOperator::getOverloadedOpcode(OO);
9587	if (IsArithmeticOp(Opc: OpKind)) {
9588	*Opcode = OpKind;
9589	*RHSExprs = Call->getArg(1);
9590	return true;
9591	}
9592	}
9593
9594	return false;
9595	}
9596
9597	/// ExprLooksBoolean - Returns true if E looks boolean, i.e. it has boolean type
9598	/// or is a logical expression such as (x==y) which has int type, but is
9599	/// commonly interpreted as boolean.
9600	static bool ExprLooksBoolean(const Expr *E) {
9601	E = E->IgnoreParenImpCasts();
9602
9603	if (E->getType()->isBooleanType())
9604	return true;
9605	if (const auto *OP = dyn_cast<BinaryOperator>(Val: E))
9606	return OP->isComparisonOp() || OP->isLogicalOp();
9607	if (const auto *OP = dyn_cast<UnaryOperator>(Val: E))
9608	return OP->getOpcode() == UO_LNot;
9609	if (E->getType()->isPointerType())
9610	return true;
9611	// FIXME: What about overloaded operator calls returning "unspecified boolean
9612	// type"s (commonly pointer-to-members)?
9613
9614	return false;
9615	}
9616
9617	/// DiagnoseConditionalPrecedence - Emit a warning when a conditional operator
9618	/// and binary operator are mixed in a way that suggests the programmer assumed
9619	/// the conditional operator has higher precedence, for example:
9620	/// "int x = a + someBinaryCondition ? 1 : 2".
9621	static void DiagnoseConditionalPrecedence(Sema &Self, SourceLocation OpLoc,
9622	Expr *Condition, const Expr *LHSExpr,
9623	const Expr *RHSExpr) {
9624	BinaryOperatorKind CondOpcode;
9625	const Expr *CondRHS;
9626
9627	if (!IsArithmeticBinaryExpr(E: Condition, Opcode: &CondOpcode, RHSExprs: &CondRHS))
9628	return;
9629	if (!ExprLooksBoolean(E: CondRHS))
9630	return;
9631
9632	// The condition is an arithmetic binary expression, with a right-
9633	// hand side that looks boolean, so warn.
9634
9635	unsigned DiagID = BinaryOperator::isBitwiseOp(CondOpcode)
9636	? diag::warn_precedence_bitwise_conditional
9637	: diag::warn_precedence_conditional;
9638
9639	Self.Diag(Loc: OpLoc, DiagID)
9640	<< Condition->getSourceRange()
9641	<< BinaryOperator::getOpcodeStr(Op: CondOpcode);
9642
9643	SuggestParentheses(
9644	Self, OpLoc,
9645	Self.PDiag(diag::note_precedence_silence)
9646	<< BinaryOperator::getOpcodeStr(CondOpcode),
9647	SourceRange(Condition->getBeginLoc(), Condition->getEndLoc()));
9648
9649	SuggestParentheses(Self, OpLoc,
9650	Self.PDiag(diag::note_precedence_conditional_first),
9651	SourceRange(CondRHS->getBeginLoc(), RHSExpr->getEndLoc()));
9652	}
9653
9654	/// Compute the nullability of a conditional expression.
9655	static QualType computeConditionalNullability(QualType ResTy, bool IsBin,
9656	QualType LHSTy, QualType RHSTy,
9657	ASTContext &Ctx) {
9658	if (!ResTy->isAnyPointerType())
9659	return ResTy;
9660
9661	auto GetNullability = [](QualType Ty) {
9662	std::optional<NullabilityKind> Kind = Ty->getNullability();
9663	if (Kind) {
9664	// For our purposes, treat _Nullable_result as _Nullable.
9665	if (*Kind == NullabilityKind::NullableResult)
9666	return NullabilityKind::Nullable;
9667	return *Kind;
9668	}
9669	return NullabilityKind::Unspecified;
9670	};
9671
9672	auto LHSKind = GetNullability(LHSTy), RHSKind = GetNullability(RHSTy);
9673	NullabilityKind MergedKind;
9674
9675	// Compute nullability of a binary conditional expression.
9676	if (IsBin) {
9677	if (LHSKind == NullabilityKind::NonNull)
9678	MergedKind = NullabilityKind::NonNull;
9679	else
9680	MergedKind = RHSKind;
9681	// Compute nullability of a normal conditional expression.
9682	} else {
9683	if (LHSKind == NullabilityKind::Nullable ||
9684	RHSKind == NullabilityKind::Nullable)
9685	MergedKind = NullabilityKind::Nullable;
9686	else if (LHSKind == NullabilityKind::NonNull)
9687	MergedKind = RHSKind;
9688	else if (RHSKind == NullabilityKind::NonNull)
9689	MergedKind = LHSKind;
9690	else
9691	MergedKind = NullabilityKind::Unspecified;
9692	}
9693
9694	// Return if ResTy already has the correct nullability.
9695	if (GetNullability(ResTy) == MergedKind)
9696	return ResTy;
9697
9698	// Strip all nullability from ResTy.
9699	while (ResTy->getNullability())
9700	ResTy = ResTy.getSingleStepDesugaredType(Context: Ctx);
9701
9702	// Create a new AttributedType with the new nullability kind.
9703	auto NewAttr = AttributedType::getNullabilityAttrKind(kind: MergedKind);
9704	return Ctx.getAttributedType(attrKind: NewAttr, modifiedType: ResTy, equivalentType: ResTy);
9705	}
9706
9707	/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null
9708	/// in the case of a the GNU conditional expr extension.
9709	ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc,
9710	SourceLocation ColonLoc,
9711	Expr *CondExpr, Expr *LHSExpr,
9712	Expr *RHSExpr) {
9713	if (!Context.isDependenceAllowed()) {
9714	// C cannot handle TypoExpr nodes in the condition because it
9715	// doesn't handle dependent types properly, so make sure any TypoExprs have
9716	// been dealt with before checking the operands.
9717	ExprResult CondResult = CorrectDelayedTyposInExpr(E: CondExpr);
9718	ExprResult LHSResult = CorrectDelayedTyposInExpr(E: LHSExpr);
9719	ExprResult RHSResult = CorrectDelayedTyposInExpr(E: RHSExpr);
9720
9721	if (!CondResult.isUsable())
9722	return ExprError();
9723
9724	if (LHSExpr) {
9725	if (!LHSResult.isUsable())
9726	return ExprError();
9727	}
9728
9729	if (!RHSResult.isUsable())
9730	return ExprError();
9731
9732	CondExpr = CondResult.get();
9733	LHSExpr = LHSResult.get();
9734	RHSExpr = RHSResult.get();
9735	}
9736
9737	// If this is the gnu "x ?: y" extension, analyze the types as though the LHS
9738	// was the condition.
9739	OpaqueValueExpr *opaqueValue = nullptr;
9740	Expr *commonExpr = nullptr;
9741	if (!LHSExpr) {
9742	commonExpr = CondExpr;
9743	// Lower out placeholder types first. This is important so that we don't
9744	// try to capture a placeholder. This happens in few cases in C++; such
9745	// as Objective-C++'s dictionary subscripting syntax.
9746	if (commonExpr->hasPlaceholderType()) {
9747	ExprResult result = CheckPlaceholderExpr(E: commonExpr);
9748	if (!result.isUsable()) return ExprError();
9749	commonExpr = result.get();
9750	}
9751	// We usually want to apply unary conversions *before* saving, except
9752	// in the special case of a C++ l-value conditional.
9753	if (!(getLangOpts().CPlusPlus
9754	&& !commonExpr->isTypeDependent()
9755	&& commonExpr->getValueKind() == RHSExpr->getValueKind()
9756	&& commonExpr->isGLValue()
9757	&& commonExpr->isOrdinaryOrBitFieldObject()
9758	&& RHSExpr->isOrdinaryOrBitFieldObject()
9759	&& Context.hasSameType(T1: commonExpr->getType(), T2: RHSExpr->getType()))) {
9760	ExprResult commonRes = UsualUnaryConversions(E: commonExpr);
9761	if (commonRes.isInvalid())
9762	return ExprError();
9763	commonExpr = commonRes.get();
9764	}
9765
9766	// If the common expression is a class or array prvalue, materialize it
9767	// so that we can safely refer to it multiple times.
9768	if (commonExpr->isPRValue() && (commonExpr->getType()->isRecordType() ||
9769	commonExpr->getType()->isArrayType())) {
9770	ExprResult MatExpr = TemporaryMaterializationConversion(E: commonExpr);
9771	if (MatExpr.isInvalid())
9772	return ExprError();
9773	commonExpr = MatExpr.get();
9774	}
9775
9776	opaqueValue = new (Context) OpaqueValueExpr(commonExpr->getExprLoc(),
9777	commonExpr->getType(),
9778	commonExpr->getValueKind(),
9779	commonExpr->getObjectKind(),
9780	commonExpr);
9781	LHSExpr = CondExpr = opaqueValue;
9782	}
9783
9784	QualType LHSTy = LHSExpr->getType(), RHSTy = RHSExpr->getType();
9785	ExprValueKind VK = VK_PRValue;
9786	ExprObjectKind OK = OK_Ordinary;
9787	ExprResult Cond = CondExpr, LHS = LHSExpr, RHS = RHSExpr;
9788	QualType result = CheckConditionalOperands(Cond, LHS, RHS,
9789	VK, OK, QuestionLoc);
9790	if (result.isNull() || Cond.isInvalid() || LHS.isInvalid() ||
9791	RHS.isInvalid())
9792	return ExprError();
9793
9794	DiagnoseConditionalPrecedence(Self&: *this, OpLoc: QuestionLoc, Condition: Cond.get(), LHSExpr: LHS.get(),
9795	RHSExpr: RHS.get());
9796
9797	CheckBoolLikeConversion(E: Cond.get(), CC: QuestionLoc);
9798
9799	result = computeConditionalNullability(ResTy: result, IsBin: commonExpr, LHSTy, RHSTy,
9800	Ctx&: Context);
9801
9802	if (!commonExpr)
9803	return new (Context)
9804	ConditionalOperator(Cond.get(), QuestionLoc, LHS.get(), ColonLoc,
9805	RHS.get(), result, VK, OK);
9806
9807	return new (Context) BinaryConditionalOperator(
9808	commonExpr, opaqueValue, Cond.get(), LHS.get(), RHS.get(), QuestionLoc,
9809	ColonLoc, result, VK, OK);
9810	}
9811
9812	// Check that the SME attributes for PSTATE.ZA and PSTATE.SM are compatible.
9813	bool Sema::IsInvalidSMECallConversion(QualType FromType, QualType ToType) {
9814	unsigned FromAttributes = 0, ToAttributes = 0;
9815	if (const auto *FromFn =
9816	dyn_cast<FunctionProtoType>(Val: Context.getCanonicalType(T: FromType)))
9817	FromAttributes =
9818	FromFn->getAArch64SMEAttributes() & FunctionType::SME_AttributeMask;
9819	if (const auto *ToFn =
9820	dyn_cast<FunctionProtoType>(Val: Context.getCanonicalType(T: ToType)))
9821	ToAttributes =
9822	ToFn->getAArch64SMEAttributes() & FunctionType::SME_AttributeMask;
9823
9824	return FromAttributes != ToAttributes;
9825	}
9826
9827	// Check if we have a conversion between incompatible cmse function pointer
9828	// types, that is, a conversion between a function pointer with the
9829	// cmse_nonsecure_call attribute and one without.
9830	static bool IsInvalidCmseNSCallConversion(Sema &S, QualType FromType,
9831	QualType ToType) {
9832	if (const auto *ToFn =
9833	dyn_cast<FunctionType>(Val: S.Context.getCanonicalType(T: ToType))) {
9834	if (const auto *FromFn =
9835	dyn_cast<FunctionType>(Val: S.Context.getCanonicalType(T: FromType))) {
9836	FunctionType::ExtInfo ToEInfo = ToFn->getExtInfo();
9837	FunctionType::ExtInfo FromEInfo = FromFn->getExtInfo();
9838
9839	return ToEInfo.getCmseNSCall() != FromEInfo.getCmseNSCall();
9840	}
9841	}
9842	return false;
9843	}
9844
9845	// checkPointerTypesForAssignment - This is a very tricky routine (despite
9846	// being closely modeled after the C99 spec:-). The odd characteristic of this
9847	// routine is it effectively iqnores the qualifiers on the top level pointee.
9848	// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3].
9849	// FIXME: add a couple examples in this comment.
9850	static Sema::AssignConvertType
9851	checkPointerTypesForAssignment(Sema &S, QualType LHSType, QualType RHSType,
9852	SourceLocation Loc) {
9853	assert(LHSType.isCanonical() && "LHS not canonicalized!");
9854	assert(RHSType.isCanonical() && "RHS not canonicalized!");
9855
9856	// get the "pointed to" type (ignoring qualifiers at the top level)
9857	const Type *lhptee, *rhptee;
9858	Qualifiers lhq, rhq;
9859	std::tie(args&: lhptee, args&: lhq) =
9860	cast<PointerType>(Val&: LHSType)->getPointeeType().split().asPair();
9861	std::tie(args&: rhptee, args&: rhq) =
9862	cast<PointerType>(Val&: RHSType)->getPointeeType().split().asPair();
9863
9864	Sema::AssignConvertType ConvTy = Sema::Compatible;
9865
9866	// C99 6.5.16.1p1: This following citation is common to constraints
9867	// 3 & 4 (below). ...and the type *pointed to* by the left has all the
9868	// qualifiers of the type *pointed to* by the right;
9869
9870	// As a special case, 'non-__weak A *' -> 'non-__weak const *' is okay.
9871	if (lhq.getObjCLifetime() != rhq.getObjCLifetime() &&
9872	lhq.compatiblyIncludesObjCLifetime(other: rhq)) {
9873	// Ignore lifetime for further calculation.
9874	lhq.removeObjCLifetime();
9875	rhq.removeObjCLifetime();
9876	}
9877
9878	if (!lhq.compatiblyIncludes(other: rhq)) {
9879	// Treat address-space mismatches as fatal.
9880	if (!lhq.isAddressSpaceSupersetOf(other: rhq))
9881	return Sema::IncompatiblePointerDiscardsQualifiers;
9882
9883	// It's okay to add or remove GC or lifetime qualifiers when converting to
9884	// and from void*.
9885	else if (lhq.withoutObjCGCAttr().withoutObjCLifetime()
9886	.compatiblyIncludes(
9887	other: rhq.withoutObjCGCAttr().withoutObjCLifetime())
9888	&& (lhptee->isVoidType() || rhptee->isVoidType()))
9889	; // keep old
9890
9891	// Treat lifetime mismatches as fatal.
9892	else if (lhq.getObjCLifetime() != rhq.getObjCLifetime())
9893	ConvTy = Sema::IncompatiblePointerDiscardsQualifiers;
9894
9895	// For GCC/MS compatibility, other qualifier mismatches are treated
9896	// as still compatible in C.
9897	else ConvTy = Sema::CompatiblePointerDiscardsQualifiers;
9898	}
9899
9900	// C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or
9901	// incomplete type and the other is a pointer to a qualified or unqualified
9902	// version of void...
9903	if (lhptee->isVoidType()) {
9904	if (rhptee->isIncompleteOrObjectType())
9905	return ConvTy;
9906
9907	// As an extension, we allow cast to/from void* to function pointer.
9908	assert(rhptee->isFunctionType());
9909	return Sema::FunctionVoidPointer;
9910	}
9911
9912	if (rhptee->isVoidType()) {
9913	if (lhptee->isIncompleteOrObjectType())
9914	return ConvTy;
9915
9916	// As an extension, we allow cast to/from void* to function pointer.
9917	assert(lhptee->isFunctionType());
9918	return Sema::FunctionVoidPointer;
9919	}
9920
9921	if (!S.Diags.isIgnored(
9922	diag::warn_typecheck_convert_incompatible_function_pointer_strict,
9923	Loc) &&
9924	RHSType->isFunctionPointerType() && LHSType->isFunctionPointerType() &&
9925	!S.IsFunctionConversion(RHSType, LHSType, RHSType))
9926	return Sema::IncompatibleFunctionPointerStrict;
9927
9928	// C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or
9929	// unqualified versions of compatible types, ...
9930	QualType ltrans = QualType(lhptee, 0), rtrans = QualType(rhptee, 0);
9931	if (!S.Context.typesAreCompatible(T1: ltrans, T2: rtrans)) {
9932	// Check if the pointee types are compatible ignoring the sign.
9933	// We explicitly check for char so that we catch "char" vs
9934	// "unsigned char" on systems where "char" is unsigned.
9935	if (lhptee->isCharType())
9936	ltrans = S.Context.UnsignedCharTy;
9937	else if (lhptee->hasSignedIntegerRepresentation())
9938	ltrans = S.Context.getCorrespondingUnsignedType(T: ltrans);
9939
9940	if (rhptee->isCharType())
9941	rtrans = S.Context.UnsignedCharTy;
9942	else if (rhptee->hasSignedIntegerRepresentation())
9943	rtrans = S.Context.getCorrespondingUnsignedType(T: rtrans);
9944
9945	if (ltrans == rtrans) {
9946	// Types are compatible ignoring the sign. Qualifier incompatibility
9947	// takes priority over sign incompatibility because the sign
9948	// warning can be disabled.
9949	if (ConvTy != Sema::Compatible)
9950	return ConvTy;
9951
9952	return Sema::IncompatiblePointerSign;
9953	}
9954
9955	// If we are a multi-level pointer, it's possible that our issue is simply
9956	// one of qualification - e.g. char ** -> const char ** is not allowed. If
9957	// the eventual target type is the same and the pointers have the same
9958	// level of indirection, this must be the issue.
9959	if (isa<PointerType>(Val: lhptee) && isa<PointerType>(Val: rhptee)) {
9960	do {
9961	std::tie(args&: lhptee, args&: lhq) =
9962	cast<PointerType>(Val: lhptee)->getPointeeType().split().asPair();
9963	std::tie(args&: rhptee, args&: rhq) =
9964	cast<PointerType>(Val: rhptee)->getPointeeType().split().asPair();
9965
9966	// Inconsistent address spaces at this point is invalid, even if the
9967	// address spaces would be compatible.
9968	// FIXME: This doesn't catch address space mismatches for pointers of
9969	// different nesting levels, like:
9970	// __local int *** a;
9971	// int ** b = a;
9972	// It's not clear how to actually determine when such pointers are
9973	// invalidly incompatible.
9974	if (lhq.getAddressSpace() != rhq.getAddressSpace())
9975	return Sema::IncompatibleNestedPointerAddressSpaceMismatch;
9976
9977	} while (isa<PointerType>(Val: lhptee) && isa<PointerType>(Val: rhptee));
9978
9979	if (lhptee == rhptee)
9980	return Sema::IncompatibleNestedPointerQualifiers;
9981	}
9982
9983	// General pointer incompatibility takes priority over qualifiers.
9984	if (RHSType->isFunctionPointerType() && LHSType->isFunctionPointerType())
9985	return Sema::IncompatibleFunctionPointer;
9986	return Sema::IncompatiblePointer;
9987	}
9988	if (!S.getLangOpts().CPlusPlus &&
9989	S.IsFunctionConversion(FromType: ltrans, ToType: rtrans, ResultTy&: ltrans))
9990	return Sema::IncompatibleFunctionPointer;
9991	if (IsInvalidCmseNSCallConversion(S, FromType: ltrans, ToType: rtrans))
9992	return Sema::IncompatibleFunctionPointer;
9993	if (S.IsInvalidSMECallConversion(FromType: rtrans, ToType: ltrans))
9994	return Sema::IncompatibleFunctionPointer;
9995	return ConvTy;
9996	}
9997
9998	/// checkBlockPointerTypesForAssignment - This routine determines whether two
9999	/// block pointer types are compatible or whether a block and normal pointer
10000	/// are compatible. It is more restrict than comparing two function pointer
10001	// types.
10002	static Sema::AssignConvertType
10003	checkBlockPointerTypesForAssignment(Sema &S, QualType LHSType,
10004	QualType RHSType) {
10005	assert(LHSType.isCanonical() && "LHS not canonicalized!");
10006	assert(RHSType.isCanonical() && "RHS not canonicalized!");
10007
10008	QualType lhptee, rhptee;
10009
10010	// get the "pointed to" type (ignoring qualifiers at the top level)
10011	lhptee = cast<BlockPointerType>(Val&: LHSType)->getPointeeType();
10012	rhptee = cast<BlockPointerType>(Val&: RHSType)->getPointeeType();
10013
10014	// In C++, the types have to match exactly.
10015	if (S.getLangOpts().CPlusPlus)
10016	return Sema::IncompatibleBlockPointer;
10017
10018	Sema::AssignConvertType ConvTy = Sema::Compatible;
10019
10020	// For blocks we enforce that qualifiers are identical.
10021	Qualifiers LQuals = lhptee.getLocalQualifiers();
10022	Qualifiers RQuals = rhptee.getLocalQualifiers();
10023	if (S.getLangOpts().OpenCL) {
10024	LQuals.removeAddressSpace();
10025	RQuals.removeAddressSpace();
10026	}
10027	if (LQuals != RQuals)
10028	ConvTy = Sema::CompatiblePointerDiscardsQualifiers;
10029
10030	// FIXME: OpenCL doesn't define the exact compile time semantics for a block
10031	// assignment.
10032	// The current behavior is similar to C++ lambdas. A block might be
10033	// assigned to a variable iff its return type and parameters are compatible
10034	// (C99 6.2.7) with the corresponding return type and parameters of the LHS of
10035	// an assignment. Presumably it should behave in way that a function pointer
10036	// assignment does in C, so for each parameter and return type:
10037	// * CVR and address space of LHS should be a superset of CVR and address
10038	// space of RHS.
10039	// * unqualified types should be compatible.
10040	if (S.getLangOpts().OpenCL) {
10041	if (!S.Context.typesAreBlockPointerCompatible(
10042	S.Context.getQualifiedType(T: LHSType.getUnqualifiedType(), Qs: LQuals),
10043	S.Context.getQualifiedType(T: RHSType.getUnqualifiedType(), Qs: RQuals)))
10044	return Sema::IncompatibleBlockPointer;
10045	} else if (!S.Context.typesAreBlockPointerCompatible(LHSType, RHSType))
10046	return Sema::IncompatibleBlockPointer;
10047
10048	return ConvTy;
10049	}
10050
10051	/// checkObjCPointerTypesForAssignment - Compares two objective-c pointer types
10052	/// for assignment compatibility.
10053	static Sema::AssignConvertType
10054	checkObjCPointerTypesForAssignment(Sema &S, QualType LHSType,
10055	QualType RHSType) {
10056	assert(LHSType.isCanonical() && "LHS was not canonicalized!");
10057	assert(RHSType.isCanonical() && "RHS was not canonicalized!");
10058
10059	if (LHSType->isObjCBuiltinType()) {
10060	// Class is not compatible with ObjC object pointers.
10061	if (LHSType->isObjCClassType() && !RHSType->isObjCBuiltinType() &&
10062	!RHSType->isObjCQualifiedClassType())
10063	return Sema::IncompatiblePointer;
10064	return Sema::Compatible;
10065	}
10066	if (RHSType->isObjCBuiltinType()) {
10067	if (RHSType->isObjCClassType() && !LHSType->isObjCBuiltinType() &&
10068	!LHSType->isObjCQualifiedClassType())
10069	return Sema::IncompatiblePointer;
10070	return Sema::Compatible;
10071	}
10072	QualType lhptee = LHSType->castAs<ObjCObjectPointerType>()->getPointeeType();
10073	QualType rhptee = RHSType->castAs<ObjCObjectPointerType>()->getPointeeType();
10074
10075	if (!lhptee.isAtLeastAsQualifiedAs(other: rhptee) &&
10076	// make an exception for id<P>
10077	!LHSType->isObjCQualifiedIdType())
10078	return Sema::CompatiblePointerDiscardsQualifiers;
10079
10080	if (S.Context.typesAreCompatible(T1: LHSType, T2: RHSType))
10081	return Sema::Compatible;
10082	if (LHSType->isObjCQualifiedIdType() || RHSType->isObjCQualifiedIdType())
10083	return Sema::IncompatibleObjCQualifiedId;
10084	return Sema::IncompatiblePointer;
10085	}
10086
10087	Sema::AssignConvertType
10088	Sema::CheckAssignmentConstraints(SourceLocation Loc,
10089	QualType LHSType, QualType RHSType) {
10090	// Fake up an opaque expression. We don't actually care about what
10091	// cast operations are required, so if CheckAssignmentConstraints
10092	// adds casts to this they'll be wasted, but fortunately that doesn't
10093	// usually happen on valid code.
10094	OpaqueValueExpr RHSExpr(Loc, RHSType, VK_PRValue);
10095	ExprResult RHSPtr = &RHSExpr;
10096	CastKind K;
10097
10098	return CheckAssignmentConstraints(LHSType, RHS&: RHSPtr, Kind&: K, /*ConvertRHS=*/false);
10099	}
10100
10101	/// This helper function returns true if QT is a vector type that has element
10102	/// type ElementType.
10103	static bool isVector(QualType QT, QualType ElementType) {
10104	if (const VectorType *VT = QT->getAs<VectorType>())
10105	return VT->getElementType().getCanonicalType() == ElementType;
10106	return false;
10107	}
10108
10109	/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently
10110	/// has code to accommodate several GCC extensions when type checking
10111	/// pointers. Here are some objectionable examples that GCC considers warnings:
10112	///
10113	/// int a, *pint;
10114	/// short *pshort;
10115	/// struct foo *pfoo;
10116	///
10117	/// pint = pshort; // warning: assignment from incompatible pointer type
10118	/// a = pint; // warning: assignment makes integer from pointer without a cast
10119	/// pint = a; // warning: assignment makes pointer from integer without a cast
10120	/// pint = pfoo; // warning: assignment from incompatible pointer type
10121	///
10122	/// As a result, the code for dealing with pointers is more complex than the
10123	/// C99 spec dictates.
10124	///
10125	/// Sets 'Kind' for any result kind except Incompatible.
10126	Sema::AssignConvertType
10127	Sema::CheckAssignmentConstraints(QualType LHSType, ExprResult &RHS,
10128	CastKind &Kind, bool ConvertRHS) {
10129	QualType RHSType = RHS.get()->getType();
10130	QualType OrigLHSType = LHSType;
10131
10132	// Get canonical types. We're not formatting these types, just comparing
10133	// them.
10134	LHSType = Context.getCanonicalType(T: LHSType).getUnqualifiedType();
10135	RHSType = Context.getCanonicalType(T: RHSType).getUnqualifiedType();
10136
10137	// Common case: no conversion required.
10138	if (LHSType == RHSType) {
10139	Kind = CK_NoOp;
10140	return Compatible;
10141	}
10142
10143	// If the LHS has an __auto_type, there are no additional type constraints
10144	// to be worried about.
10145	if (const auto *AT = dyn_cast<AutoType>(Val&: LHSType)) {
10146	if (AT->isGNUAutoType()) {
10147	Kind = CK_NoOp;
10148	return Compatible;
10149	}
10150	}
10151
10152	// If we have an atomic type, try a non-atomic assignment, then just add an
10153	// atomic qualification step.
10154	if (const AtomicType *AtomicTy = dyn_cast<AtomicType>(Val&: LHSType)) {
10155	Sema::AssignConvertType result =
10156	CheckAssignmentConstraints(LHSType: AtomicTy->getValueType(), RHS, Kind);
10157	if (result != Compatible)
10158	return result;
10159	if (Kind != CK_NoOp && ConvertRHS)
10160	RHS = ImpCastExprToType(E: RHS.get(), Type: AtomicTy->getValueType(), CK: Kind);
10161	Kind = CK_NonAtomicToAtomic;
10162	return Compatible;
10163	}
10164
10165	// If the left-hand side is a reference type, then we are in a
10166	// (rare!) case where we've allowed the use of references in C,
10167	// e.g., as a parameter type in a built-in function. In this case,
10168	// just make sure that the type referenced is compatible with the
10169	// right-hand side type. The caller is responsible for adjusting
10170	// LHSType so that the resulting expression does not have reference
10171	// type.
10172	if (const ReferenceType *LHSTypeRef = LHSType->getAs<ReferenceType>()) {
10173	if (Context.typesAreCompatible(T1: LHSTypeRef->getPointeeType(), T2: RHSType)) {
10174	Kind = CK_LValueBitCast;
10175	return Compatible;
10176	}
10177	return Incompatible;
10178	}
10179
10180	// Allow scalar to ExtVector assignments, and assignments of an ExtVector type
10181	// to the same ExtVector type.
10182	if (LHSType->isExtVectorType()) {
10183	if (RHSType->isExtVectorType())
10184	return Incompatible;
10185	if (RHSType->isArithmeticType()) {
10186	// CK_VectorSplat does T -> vector T, so first cast to the element type.
10187	if (ConvertRHS)
10188	RHS = prepareVectorSplat(VectorTy: LHSType, SplattedExpr: RHS.get());
10189	Kind = CK_VectorSplat;
10190	return Compatible;
10191	}
10192	}
10193
10194	// Conversions to or from vector type.
10195	if (LHSType->isVectorType() || RHSType->isVectorType()) {
10196	if (LHSType->isVectorType() && RHSType->isVectorType()) {
10197	// Allow assignments of an AltiVec vector type to an equivalent GCC
10198	// vector type and vice versa
10199	if (Context.areCompatibleVectorTypes(FirstVec: LHSType, SecondVec: RHSType)) {
10200	Kind = CK_BitCast;
10201	return Compatible;
10202	}
10203
10204	// If we are allowing lax vector conversions, and LHS and RHS are both
10205	// vectors, the total size only needs to be the same. This is a bitcast;
10206	// no bits are changed but the result type is different.
10207	if (isLaxVectorConversion(srcTy: RHSType, destTy: LHSType)) {
10208	// The default for lax vector conversions with Altivec vectors will
10209	// change, so if we are converting between vector types where
10210	// at least one is an Altivec vector, emit a warning.
10211	if (Context.getTargetInfo().getTriple().isPPC() &&
10212	anyAltivecTypes(RHSType, LHSType) &&
10213	!Context.areCompatibleVectorTypes(RHSType, LHSType))
10214	Diag(RHS.get()->getExprLoc(), diag::warn_deprecated_lax_vec_conv_all)
10215	<< RHSType << LHSType;
10216	Kind = CK_BitCast;
10217	return IncompatibleVectors;
10218	}
10219	}
10220
10221	// When the RHS comes from another lax conversion (e.g. binops between
10222	// scalars and vectors) the result is canonicalized as a vector. When the
10223	// LHS is also a vector, the lax is allowed by the condition above. Handle
10224	// the case where LHS is a scalar.
10225	if (LHSType->isScalarType()) {
10226	const VectorType *VecType = RHSType->getAs<VectorType>();
10227	if (VecType && VecType->getNumElements() == 1 &&
10228	isLaxVectorConversion(srcTy: RHSType, destTy: LHSType)) {
10229	if (Context.getTargetInfo().getTriple().isPPC() &&
10230	(VecType->getVectorKind() == VectorKind::AltiVecVector ||
10231	VecType->getVectorKind() == VectorKind::AltiVecBool ||
10232	VecType->getVectorKind() == VectorKind::AltiVecPixel))
10233	Diag(RHS.get()->getExprLoc(), diag::warn_deprecated_lax_vec_conv_all)
10234	<< RHSType << LHSType;
10235	ExprResult *VecExpr = &RHS;
10236	*VecExpr = ImpCastExprToType(E: VecExpr->get(), Type: LHSType, CK: CK_BitCast);
10237	Kind = CK_BitCast;
10238	return Compatible;
10239	}
10240	}
10241
10242	// Allow assignments between fixed-length and sizeless SVE vectors.
10243	if ((LHSType->isSVESizelessBuiltinType() && RHSType->isVectorType()) ||
10244	(LHSType->isVectorType() && RHSType->isSVESizelessBuiltinType()))
10245	if (Context.areCompatibleSveTypes(FirstType: LHSType, SecondType: RHSType) ||
10246	Context.areLaxCompatibleSveTypes(FirstType: LHSType, SecondType: RHSType)) {
10247	Kind = CK_BitCast;
10248	return Compatible;
10249	}
10250
10251	// Allow assignments between fixed-length and sizeless RVV vectors.
10252	if ((LHSType->isRVVSizelessBuiltinType() && RHSType->isVectorType()) ||
10253	(LHSType->isVectorType() && RHSType->isRVVSizelessBuiltinType())) {
10254	if (Context.areCompatibleRVVTypes(FirstType: LHSType, SecondType: RHSType) ||
10255	Context.areLaxCompatibleRVVTypes(FirstType: LHSType, SecondType: RHSType)) {
10256	Kind = CK_BitCast;
10257	return Compatible;
10258	}
10259	}
10260
10261	return Incompatible;
10262	}
10263
10264	// Diagnose attempts to convert between __ibm128, __float128 and long double
10265	// where such conversions currently can't be handled.
10266	if (unsupportedTypeConversion(S: *this, LHSType, RHSType))
10267	return Incompatible;
10268
10269	// Disallow assigning a _Complex to a real type in C++ mode since it simply
10270	// discards the imaginary part.
10271	if (getLangOpts().CPlusPlus && RHSType->getAs<ComplexType>() &&
10272	!LHSType->getAs<ComplexType>())
10273	return Incompatible;
10274
10275	// Arithmetic conversions.
10276	if (LHSType->isArithmeticType() && RHSType->isArithmeticType() &&
10277	!(getLangOpts().CPlusPlus && LHSType->isEnumeralType())) {
10278	if (ConvertRHS)
10279	Kind = PrepareScalarCast(Src&: RHS, DestTy: LHSType);
10280	return Compatible;
10281	}
10282
10283	// Conversions to normal pointers.
10284	if (const PointerType *LHSPointer = dyn_cast<PointerType>(Val&: LHSType)) {
10285	// U* -> T*
10286	if (isa<PointerType>(Val: RHSType)) {
10287	LangAS AddrSpaceL = LHSPointer->getPointeeType().getAddressSpace();
10288	LangAS AddrSpaceR = RHSType->getPointeeType().getAddressSpace();
10289	if (AddrSpaceL != AddrSpaceR)
10290	Kind = CK_AddressSpaceConversion;
10291	else if (Context.hasCvrSimilarType(T1: RHSType, T2: LHSType))
10292	Kind = CK_NoOp;
10293	else
10294	Kind = CK_BitCast;
10295	return checkPointerTypesForAssignment(*this, LHSType, RHSType,
10296	RHS.get()->getBeginLoc());
10297	}
10298
10299	// int -> T*
10300	if (RHSType->isIntegerType()) {
10301	Kind = CK_IntegralToPointer; // FIXME: null?
10302	return IntToPointer;
10303	}
10304
10305	// C pointers are not compatible with ObjC object pointers,
10306	// with two exceptions:
10307	if (isa<ObjCObjectPointerType>(Val: RHSType)) {
10308	// - conversions to void*
10309	if (LHSPointer->getPointeeType()->isVoidType()) {
10310	Kind = CK_BitCast;
10311	return Compatible;
10312	}
10313
10314	// - conversions from 'Class' to the redefinition type
10315	if (RHSType->isObjCClassType() &&
10316	Context.hasSameType(T1: LHSType,
10317	T2: Context.getObjCClassRedefinitionType())) {
10318	Kind = CK_BitCast;
10319	return Compatible;
10320	}
10321
10322	Kind = CK_BitCast;
10323	return IncompatiblePointer;
10324	}
10325
10326	// U^ -> void*
10327	if (RHSType->getAs<BlockPointerType>()) {
10328	if (LHSPointer->getPointeeType()->isVoidType()) {
10329	LangAS AddrSpaceL = LHSPointer->getPointeeType().getAddressSpace();
10330	LangAS AddrSpaceR = RHSType->getAs<BlockPointerType>()
10331	->getPointeeType()
10332	.getAddressSpace();
10333	Kind =
10334	AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
10335	return Compatible;
10336	}
10337	}
10338
10339	return Incompatible;
10340	}
10341
10342	// Conversions to block pointers.
10343	if (isa<BlockPointerType>(Val: LHSType)) {
10344	// U^ -> T^
10345	if (RHSType->isBlockPointerType()) {
10346	LangAS AddrSpaceL = LHSType->getAs<BlockPointerType>()
10347	->getPointeeType()
10348	.getAddressSpace();
10349	LangAS AddrSpaceR = RHSType->getAs<BlockPointerType>()
10350	->getPointeeType()
10351	.getAddressSpace();
10352	Kind = AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
10353	return checkBlockPointerTypesForAssignment(S&: *this, LHSType, RHSType);
10354	}
10355
10356	// int or null -> T^
10357	if (RHSType->isIntegerType()) {
10358	Kind = CK_IntegralToPointer; // FIXME: null
10359	return IntToBlockPointer;
10360	}
10361
10362	// id -> T^
10363	if (getLangOpts().ObjC && RHSType->isObjCIdType()) {
10364	Kind = CK_AnyPointerToBlockPointerCast;
10365	return Compatible;
10366	}
10367
10368	// void* -> T^
10369	if (const PointerType *RHSPT = RHSType->getAs<PointerType>())
10370	if (RHSPT->getPointeeType()->isVoidType()) {
10371	Kind = CK_AnyPointerToBlockPointerCast;
10372	return Compatible;
10373	}
10374
10375	return Incompatible;
10376	}
10377
10378	// Conversions to Objective-C pointers.
10379	if (isa<ObjCObjectPointerType>(Val: LHSType)) {
10380	// A* -> B*
10381	if (RHSType->isObjCObjectPointerType()) {
10382	Kind = CK_BitCast;
10383	Sema::AssignConvertType result =
10384	checkObjCPointerTypesForAssignment(S&: *this, LHSType, RHSType);
10385	if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
10386	result == Compatible &&
10387	!CheckObjCARCUnavailableWeakConversion(castType: OrigLHSType, ExprType: RHSType))
10388	result = IncompatibleObjCWeakRef;
10389	return result;
10390	}
10391
10392	// int or null -> A*
10393	if (RHSType->isIntegerType()) {
10394	Kind = CK_IntegralToPointer; // FIXME: null
10395	return IntToPointer;
10396	}
10397
10398	// In general, C pointers are not compatible with ObjC object pointers,
10399	// with two exceptions:
10400	if (isa<PointerType>(Val: RHSType)) {
10401	Kind = CK_CPointerToObjCPointerCast;
10402
10403	// - conversions from 'void*'
10404	if (RHSType->isVoidPointerType()) {
10405	return Compatible;
10406	}
10407
10408	// - conversions to 'Class' from its redefinition type
10409	if (LHSType->isObjCClassType() &&
10410	Context.hasSameType(T1: RHSType,
10411	T2: Context.getObjCClassRedefinitionType())) {
10412	return Compatible;
10413	}
10414
10415	return IncompatiblePointer;
10416	}
10417
10418	// Only under strict condition T^ is compatible with an Objective-C pointer.
10419	if (RHSType->isBlockPointerType() &&
10420	LHSType->isBlockCompatibleObjCPointerType(ctx&: Context)) {
10421	if (ConvertRHS)
10422	maybeExtendBlockObject(E&: RHS);
10423	Kind = CK_BlockPointerToObjCPointerCast;
10424	return Compatible;
10425	}
10426
10427	return Incompatible;
10428	}
10429
10430	// Conversion to nullptr_t (C23 only)
10431	if (getLangOpts().C23 && LHSType->isNullPtrType() &&
10432	RHS.get()->isNullPointerConstant(Ctx&: Context,
10433	NPC: Expr::NPC_ValueDependentIsNull)) {
10434	// null -> nullptr_t
10435	Kind = CK_NullToPointer;
10436	return Compatible;
10437	}
10438
10439	// Conversions from pointers that are not covered by the above.
10440	if (isa<PointerType>(Val: RHSType)) {
10441	// T* -> _Bool
10442	if (LHSType == Context.BoolTy) {
10443	Kind = CK_PointerToBoolean;
10444	return Compatible;
10445	}
10446
10447	// T* -> int
10448	if (LHSType->isIntegerType()) {
10449	Kind = CK_PointerToIntegral;
10450	return PointerToInt;
10451	}
10452
10453	return Incompatible;
10454	}
10455
10456	// Conversions from Objective-C pointers that are not covered by the above.
10457	if (isa<ObjCObjectPointerType>(Val: RHSType)) {
10458	// T* -> _Bool
10459	if (LHSType == Context.BoolTy) {
10460	Kind = CK_PointerToBoolean;
10461	return Compatible;
10462	}
10463
10464	// T* -> int
10465	if (LHSType->isIntegerType()) {
10466	Kind = CK_PointerToIntegral;
10467	return PointerToInt;
10468	}
10469
10470	return Incompatible;
10471	}
10472
10473	// struct A -> struct B
10474	if (isa<TagType>(Val: LHSType) && isa<TagType>(Val: RHSType)) {
10475	if (Context.typesAreCompatible(T1: LHSType, T2: RHSType)) {
10476	Kind = CK_NoOp;
10477	return Compatible;
10478	}
10479	}
10480
10481	if (LHSType->isSamplerT() && RHSType->isIntegerType()) {
10482	Kind = CK_IntToOCLSampler;
10483	return Compatible;
10484	}
10485
10486	return Incompatible;
10487	}
10488
10489	/// Constructs a transparent union from an expression that is
10490	/// used to initialize the transparent union.
10491	static void ConstructTransparentUnion(Sema &S, ASTContext &C,
10492	ExprResult &EResult, QualType UnionType,
10493	FieldDecl *Field) {
10494	// Build an initializer list that designates the appropriate member
10495	// of the transparent union.
10496	Expr *E = EResult.get();
10497	InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(),
10498	E, SourceLocation());
10499	Initializer->setType(UnionType);
10500	Initializer->setInitializedFieldInUnion(Field);
10501
10502	// Build a compound literal constructing a value of the transparent
10503	// union type from this initializer list.
10504	TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(T: UnionType);
10505	EResult = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType,
10506	VK_PRValue, Initializer, false);
10507	}
10508
10509	Sema::AssignConvertType
10510	Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType,
10511	ExprResult &RHS) {
10512	QualType RHSType = RHS.get()->getType();
10513
10514	// If the ArgType is a Union type, we want to handle a potential
10515	// transparent_union GCC extension.
10516	const RecordType *UT = ArgType->getAsUnionType();
10517	if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>())
10518	return Incompatible;
10519
10520	// The field to initialize within the transparent union.
10521	RecordDecl *UD = UT->getDecl();
10522	FieldDecl *InitField = nullptr;
10523	// It's compatible if the expression matches any of the fields.
10524	for (auto *it : UD->fields()) {
10525	if (it->getType()->isPointerType()) {
10526	// If the transparent union contains a pointer type, we allow:
10527	// 1) void pointer
10528	// 2) null pointer constant
10529	if (RHSType->isPointerType())
10530	if (RHSType->castAs<PointerType>()->getPointeeType()->isVoidType()) {
10531	RHS = ImpCastExprToType(RHS.get(), it->getType(), CK_BitCast);
10532	InitField = it;
10533	break;
10534	}
10535
10536	if (RHS.get()->isNullPointerConstant(Context,
10537	Expr::NPC_ValueDependentIsNull)) {
10538	RHS = ImpCastExprToType(RHS.get(), it->getType(),
10539	CK_NullToPointer);
10540	InitField = it;
10541	break;
10542	}
10543	}
10544
10545	CastKind Kind;
10546	if (CheckAssignmentConstraints(it->getType(), RHS, Kind)
10547	== Compatible) {
10548	RHS = ImpCastExprToType(RHS.get(), it->getType(), Kind);
10549	InitField = it;
10550	break;
10551	}
10552	}
10553
10554	if (!InitField)
10555	return Incompatible;
10556
10557	ConstructTransparentUnion(S&: *this, C&: Context, EResult&: RHS, UnionType: ArgType, Field: InitField);
10558	return Compatible;
10559	}
10560
10561	Sema::AssignConvertType
10562	Sema::CheckSingleAssignmentConstraints(QualType LHSType, ExprResult &CallerRHS,
10563	bool Diagnose,
10564	bool DiagnoseCFAudited,
10565	bool ConvertRHS) {
10566	// We need to be able to tell the caller whether we diagnosed a problem, if
10567	// they ask us to issue diagnostics.
10568	assert((ConvertRHS || !Diagnose) && "can't indicate whether we diagnosed");
10569
10570	// If ConvertRHS is false, we want to leave the caller's RHS untouched. Sadly,
10571	// we can't avoid *all* modifications at the moment, so we need some somewhere
10572	// to put the updated value.
10573	ExprResult LocalRHS = CallerRHS;
10574	ExprResult &RHS = ConvertRHS ? CallerRHS : LocalRHS;
10575
10576	if (const auto *LHSPtrType = LHSType->getAs<PointerType>()) {
10577	if (const auto *RHSPtrType = RHS.get()->getType()->getAs<PointerType>()) {
10578	if (RHSPtrType->getPointeeType()->hasAttr(attr::NoDeref) &&
10579	!LHSPtrType->getPointeeType()->hasAttr(attr::NoDeref)) {
10580	Diag(RHS.get()->getExprLoc(),
10581	diag::warn_noderef_to_dereferenceable_pointer)
10582	<< RHS.get()->getSourceRange();
10583	}
10584	}
10585	}
10586
10587	if (getLangOpts().CPlusPlus) {
10588	if (!LHSType->isRecordType() && !LHSType->isAtomicType()) {
10589	// C++ 5.17p3: If the left operand is not of class type, the
10590	// expression is implicitly converted (C++ 4) to the
10591	// cv-unqualified type of the left operand.
10592	QualType RHSType = RHS.get()->getType();
10593	if (Diagnose) {
10594	RHS = PerformImplicitConversion(From: RHS.get(), ToType: LHSType.getUnqualifiedType(),
10595	Action: AA_Assigning);
10596	} else {
10597	ImplicitConversionSequence ICS =
10598	TryImplicitConversion(From: RHS.get(), ToType: LHSType.getUnqualifiedType(),
10599	/*SuppressUserConversions=*/false,
10600	AllowExplicit: AllowedExplicit::None,
10601	/*InOverloadResolution=*/false,
10602	/*CStyle=*/false,
10603	/*AllowObjCWritebackConversion=*/false);
10604	if (ICS.isFailure())
10605	return Incompatible;
10606	RHS = PerformImplicitConversion(From: RHS.get(), ToType: LHSType.getUnqualifiedType(),
10607	ICS, Action: AA_Assigning);
10608	}
10609	if (RHS.isInvalid())
10610	return Incompatible;
10611	Sema::AssignConvertType result = Compatible;
10612	if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
10613	!CheckObjCARCUnavailableWeakConversion(castType: LHSType, ExprType: RHSType))
10614	result = IncompatibleObjCWeakRef;
10615	return result;
10616	}
10617
10618	// FIXME: Currently, we fall through and treat C++ classes like C
10619	// structures.
10620	// FIXME: We also fall through for atomics; not sure what should
10621	// happen there, though.
10622	} else if (RHS.get()->getType() == Context.OverloadTy) {
10623	// As a set of extensions to C, we support overloading on functions. These
10624	// functions need to be resolved here.
10625	DeclAccessPair DAP;
10626	if (FunctionDecl *FD = ResolveAddressOfOverloadedFunction(
10627	AddressOfExpr: RHS.get(), TargetType: LHSType, /*Complain=*/false, Found&: DAP))
10628	RHS = FixOverloadedFunctionReference(E: RHS.get(), FoundDecl: DAP, Fn: FD);
10629	else
10630	return Incompatible;
10631	}
10632
10633	// This check seems unnatural, however it is necessary to ensure the proper
10634	// conversion of functions/arrays. If the conversion were done for all
10635	// DeclExpr's (created by ActOnIdExpression), it would mess up the unary
10636	// expressions that suppress this implicit conversion (&, sizeof). This needs
10637	// to happen before we check for null pointer conversions because C does not
10638	// undergo the same implicit conversions as C++ does above (by the calls to
10639	// TryImplicitConversion() and PerformImplicitConversion()) which insert the
10640	// lvalue to rvalue cast before checking for null pointer constraints. This
10641	// addresses code like: nullptr_t val; int *ptr; ptr = val;
10642	//
10643	// Suppress this for references: C++ 8.5.3p5.
10644	if (!LHSType->isReferenceType()) {
10645	// FIXME: We potentially allocate here even if ConvertRHS is false.
10646	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get(), Diagnose);
10647	if (RHS.isInvalid())
10648	return Incompatible;
10649	}
10650
10651	// The constraints are expressed in terms of the atomic, qualified, or
10652	// unqualified type of the LHS.
10653	QualType LHSTypeAfterConversion = LHSType.getAtomicUnqualifiedType();
10654
10655	// C99 6.5.16.1p1: the left operand is a pointer and the right is
10656	// a null pointer constant <C23>or its type is nullptr_t;</C23>.
10657	if ((LHSTypeAfterConversion->isPointerType() ||
10658	LHSTypeAfterConversion->isObjCObjectPointerType() ||
10659	LHSTypeAfterConversion->isBlockPointerType()) &&
10660	((getLangOpts().C23 && RHS.get()->getType()->isNullPtrType()) ||
10661	RHS.get()->isNullPointerConstant(Ctx&: Context,
10662	NPC: Expr::NPC_ValueDependentIsNull))) {
10663	if (Diagnose || ConvertRHS) {
10664	CastKind Kind;
10665	CXXCastPath Path;
10666	CheckPointerConversion(From: RHS.get(), ToType: LHSType, Kind, BasePath&: Path,
10667	/*IgnoreBaseAccess=*/false, Diagnose);
10668	if (ConvertRHS)
10669	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: Kind, VK: VK_PRValue, BasePath: &Path);
10670	}
10671	return Compatible;
10672	}
10673	// C23 6.5.16.1p1: the left operand has type atomic, qualified, or
10674	// unqualified bool, and the right operand is a pointer or its type is
10675	// nullptr_t.
10676	if (getLangOpts().C23 && LHSType->isBooleanType() &&
10677	RHS.get()->getType()->isNullPtrType()) {
10678	// NB: T* -> _Bool is handled in CheckAssignmentConstraints, this only
10679	// only handles nullptr -> _Bool due to needing an extra conversion
10680	// step.
10681	// We model this by converting from nullptr -> void * and then let the
10682	// conversion from void * -> _Bool happen naturally.
10683	if (Diagnose || ConvertRHS) {
10684	CastKind Kind;
10685	CXXCastPath Path;
10686	CheckPointerConversion(From: RHS.get(), ToType: Context.VoidPtrTy, Kind, BasePath&: Path,
10687	/*IgnoreBaseAccess=*/false, Diagnose);
10688	if (ConvertRHS)
10689	RHS = ImpCastExprToType(E: RHS.get(), Type: Context.VoidPtrTy, CK: Kind, VK: VK_PRValue,
10690	BasePath: &Path);
10691	}
10692	}
10693
10694	// OpenCL queue_t type assignment.
10695	if (LHSType->isQueueT() && RHS.get()->isNullPointerConstant(
10696	Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNull)) {
10697	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
10698	return Compatible;
10699	}
10700
10701	CastKind Kind;
10702	Sema::AssignConvertType result =
10703	CheckAssignmentConstraints(LHSType, RHS, Kind, ConvertRHS);
10704
10705	// C99 6.5.16.1p2: The value of the right operand is converted to the
10706	// type of the assignment expression.
10707	// CheckAssignmentConstraints allows the left-hand side to be a reference,
10708	// so that we can use references in built-in functions even in C.
10709	// The getNonReferenceType() call makes sure that the resulting expression
10710	// does not have reference type.
10711	if (result != Incompatible && RHS.get()->getType() != LHSType) {
10712	QualType Ty = LHSType.getNonLValueExprType(Context);
10713	Expr *E = RHS.get();
10714
10715	// Check for various Objective-C errors. If we are not reporting
10716	// diagnostics and just checking for errors, e.g., during overload
10717	// resolution, return Incompatible to indicate the failure.
10718	if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
10719	CheckObjCConversion(castRange: SourceRange(), castType: Ty, op&: E, CCK: CCK_ImplicitConversion,
10720	Diagnose, DiagnoseCFAudited) != ACR_okay) {
10721	if (!Diagnose)
10722	return Incompatible;
10723	}
10724	if (getLangOpts().ObjC &&
10725	(CheckObjCBridgeRelatedConversions(Loc: E->getBeginLoc(), DestType: LHSType,
10726	SrcType: E->getType(), SrcExpr&: E, Diagnose) ||
10727	CheckConversionToObjCLiteral(DstType: LHSType, SrcExpr&: E, Diagnose))) {
10728	if (!Diagnose)
10729	return Incompatible;
10730	// Replace the expression with a corrected version and continue so we
10731	// can find further errors.
10732	RHS = E;
10733	return Compatible;
10734	}
10735
10736	if (ConvertRHS)
10737	RHS = ImpCastExprToType(E, Type: Ty, CK: Kind);
10738	}
10739
10740	return result;
10741	}
10742
10743	namespace {
10744	/// The original operand to an operator, prior to the application of the usual
10745	/// arithmetic conversions and converting the arguments of a builtin operator
10746	/// candidate.
10747	struct OriginalOperand {
10748	explicit OriginalOperand(Expr *Op) : Orig(Op), Conversion(nullptr) {
10749	if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(Val: Op))
10750	Op = MTE->getSubExpr();
10751	if (auto *BTE = dyn_cast<CXXBindTemporaryExpr>(Val: Op))
10752	Op = BTE->getSubExpr();
10753	if (auto *ICE = dyn_cast<ImplicitCastExpr>(Val: Op)) {
10754	Orig = ICE->getSubExprAsWritten();
10755	Conversion = ICE->getConversionFunction();
10756	}
10757	}
10758
10759	QualType getType() const { return Orig->getType(); }
10760
10761	Expr *Orig;
10762	NamedDecl *Conversion;
10763	};
10764	}
10765
10766	QualType Sema::InvalidOperands(SourceLocation Loc, ExprResult &LHS,
10767	ExprResult &RHS) {
10768	OriginalOperand OrigLHS(LHS.get()), OrigRHS(RHS.get());
10769
10770	Diag(Loc, diag::err_typecheck_invalid_operands)
10771	<< OrigLHS.getType() << OrigRHS.getType()
10772	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
10773
10774	// If a user-defined conversion was applied to either of the operands prior
10775	// to applying the built-in operator rules, tell the user about it.
10776	if (OrigLHS.Conversion) {
10777	Diag(OrigLHS.Conversion->getLocation(),
10778	diag::note_typecheck_invalid_operands_converted)
10779	<< 0 << LHS.get()->getType();
10780	}
10781	if (OrigRHS.Conversion) {
10782	Diag(OrigRHS.Conversion->getLocation(),
10783	diag::note_typecheck_invalid_operands_converted)
10784	<< 1 << RHS.get()->getType();
10785	}
10786
10787	return QualType();
10788	}
10789
10790	// Diagnose cases where a scalar was implicitly converted to a vector and
10791	// diagnose the underlying types. Otherwise, diagnose the error
10792	// as invalid vector logical operands for non-C++ cases.
10793	QualType Sema::InvalidLogicalVectorOperands(SourceLocation Loc, ExprResult &LHS,
10794	ExprResult &RHS) {
10795	QualType LHSType = LHS.get()->IgnoreImpCasts()->getType();
10796	QualType RHSType = RHS.get()->IgnoreImpCasts()->getType();
10797
10798	bool LHSNatVec = LHSType->isVectorType();
10799	bool RHSNatVec = RHSType->isVectorType();
10800
10801	if (!(LHSNatVec && RHSNatVec)) {
10802	Expr *Vector = LHSNatVec ? LHS.get() : RHS.get();
10803	Expr *NonVector = !LHSNatVec ? LHS.get() : RHS.get();
10804	Diag(Loc, diag::err_typecheck_logical_vector_expr_gnu_cpp_restrict)
10805	<< 0 << Vector->getType() << NonVector->IgnoreImpCasts()->getType()
10806	<< Vector->getSourceRange();
10807	return QualType();
10808	}
10809
10810	Diag(Loc, diag::err_typecheck_logical_vector_expr_gnu_cpp_restrict)
10811	<< 1 << LHSType << RHSType << LHS.get()->getSourceRange()
10812	<< RHS.get()->getSourceRange();
10813
10814	return QualType();
10815	}
10816
10817	/// Try to convert a value of non-vector type to a vector type by converting
10818	/// the type to the element type of the vector and then performing a splat.
10819	/// If the language is OpenCL, we only use conversions that promote scalar
10820	/// rank; for C, Obj-C, and C++ we allow any real scalar conversion except
10821	/// for float->int.
10822	///
10823	/// OpenCL V2.0 6.2.6.p2:
10824	/// An error shall occur if any scalar operand type has greater rank
10825	/// than the type of the vector element.
10826	///
10827	/// \param scalar - if non-null, actually perform the conversions
10828	/// \return true if the operation fails (but without diagnosing the failure)
10829	static bool tryVectorConvertAndSplat(Sema &S, ExprResult *scalar,
10830	QualType scalarTy,
10831	QualType vectorEltTy,
10832	QualType vectorTy,
10833	unsigned &DiagID) {
10834	// The conversion to apply to the scalar before splatting it,
10835	// if necessary.
10836	CastKind scalarCast = CK_NoOp;
10837
10838	if (vectorEltTy->isIntegralType(Ctx: S.Context)) {
10839	if (S.getLangOpts().OpenCL && (scalarTy->isRealFloatingType() ||
10840	(scalarTy->isIntegerType() &&
10841	S.Context.getIntegerTypeOrder(LHS: vectorEltTy, RHS: scalarTy) < 0))) {
10842	DiagID = diag::err_opencl_scalar_type_rank_greater_than_vector_type;
10843	return true;
10844	}
10845	if (!scalarTy->isIntegralType(Ctx: S.Context))
10846	return true;
10847	scalarCast = CK_IntegralCast;
10848	} else if (vectorEltTy->isRealFloatingType()) {
10849	if (scalarTy->isRealFloatingType()) {
10850	if (S.getLangOpts().OpenCL &&
10851	S.Context.getFloatingTypeOrder(LHS: vectorEltTy, RHS: scalarTy) < 0) {
10852	DiagID = diag::err_opencl_scalar_type_rank_greater_than_vector_type;
10853	return true;
10854	}
10855	scalarCast = CK_FloatingCast;
10856	}
10857	else if (scalarTy->isIntegralType(Ctx: S.Context))
10858	scalarCast = CK_IntegralToFloating;
10859	else
10860	return true;
10861	} else {
10862	return true;
10863	}
10864
10865	// Adjust scalar if desired.
10866	if (scalar) {
10867	if (scalarCast != CK_NoOp)
10868	*scalar = S.ImpCastExprToType(E: scalar->get(), Type: vectorEltTy, CK: scalarCast);
10869	*scalar = S.ImpCastExprToType(E: scalar->get(), Type: vectorTy, CK: CK_VectorSplat);
10870	}
10871	return false;
10872	}
10873
10874	/// Convert vector E to a vector with the same number of elements but different
10875	/// element type.
10876	static ExprResult convertVector(Expr *E, QualType ElementType, Sema &S) {
10877	const auto *VecTy = E->getType()->getAs<VectorType>();
10878	assert(VecTy && "Expression E must be a vector");
10879	QualType NewVecTy =
10880	VecTy->isExtVectorType()
10881	? S.Context.getExtVectorType(VectorType: ElementType, NumElts: VecTy->getNumElements())
10882	: S.Context.getVectorType(VectorType: ElementType, NumElts: VecTy->getNumElements(),
10883	VecKind: VecTy->getVectorKind());
10884
10885	// Look through the implicit cast. Return the subexpression if its type is
10886	// NewVecTy.
10887	if (auto *ICE = dyn_cast<ImplicitCastExpr>(Val: E))
10888	if (ICE->getSubExpr()->getType() == NewVecTy)
10889	return ICE->getSubExpr();
10890
10891	auto Cast = ElementType->isIntegerType() ? CK_IntegralCast : CK_FloatingCast;
10892	return S.ImpCastExprToType(E, Type: NewVecTy, CK: Cast);
10893	}
10894
10895	/// Test if a (constant) integer Int can be casted to another integer type
10896	/// IntTy without losing precision.
10897	static bool canConvertIntToOtherIntTy(Sema &S, ExprResult *Int,
10898	QualType OtherIntTy) {
10899	QualType IntTy = Int->get()->getType().getUnqualifiedType();
10900
10901	// Reject cases where the value of the Int is unknown as that would
10902	// possibly cause truncation, but accept cases where the scalar can be
10903	// demoted without loss of precision.
10904	Expr::EvalResult EVResult;
10905	bool CstInt = Int->get()->EvaluateAsInt(Result&: EVResult, Ctx: S.Context);
10906	int Order = S.Context.getIntegerTypeOrder(LHS: OtherIntTy, RHS: IntTy);
10907	bool IntSigned = IntTy->hasSignedIntegerRepresentation();
10908	bool OtherIntSigned = OtherIntTy->hasSignedIntegerRepresentation();
10909
10910	if (CstInt) {
10911	// If the scalar is constant and is of a higher order and has more active
10912	// bits that the vector element type, reject it.
10913	llvm::APSInt Result = EVResult.Val.getInt();
10914	unsigned NumBits = IntSigned
10915	? (Result.isNegative() ? Result.getSignificantBits()
10916	: Result.getActiveBits())
10917	: Result.getActiveBits();
10918	if (Order < 0 && S.Context.getIntWidth(T: OtherIntTy) < NumBits)
10919	return true;
10920
10921	// If the signedness of the scalar type and the vector element type
10922	// differs and the number of bits is greater than that of the vector
10923	// element reject it.
10924	return (IntSigned != OtherIntSigned &&
10925	NumBits > S.Context.getIntWidth(T: OtherIntTy));
10926	}
10927
10928	// Reject cases where the value of the scalar is not constant and it's
10929	// order is greater than that of the vector element type.
10930	return (Order < 0);
10931	}
10932
10933	/// Test if a (constant) integer Int can be casted to floating point type
10934	/// FloatTy without losing precision.
10935	static bool canConvertIntTyToFloatTy(Sema &S, ExprResult *Int,
10936	QualType FloatTy) {
10937	QualType IntTy = Int->get()->getType().getUnqualifiedType();
10938
10939	// Determine if the integer constant can be expressed as a floating point
10940	// number of the appropriate type.
10941	Expr::EvalResult EVResult;
10942	bool CstInt = Int->get()->EvaluateAsInt(Result&: EVResult, Ctx: S.Context);
10943
10944	uint64_t Bits = 0;
10945	if (CstInt) {
10946	// Reject constants that would be truncated if they were converted to
10947	// the floating point type. Test by simple to/from conversion.
10948	// FIXME: Ideally the conversion to an APFloat and from an APFloat
10949	// could be avoided if there was a convertFromAPInt method
10950	// which could signal back if implicit truncation occurred.
10951	llvm::APSInt Result = EVResult.Val.getInt();
10952	llvm::APFloat Float(S.Context.getFloatTypeSemantics(T: FloatTy));
10953	Float.convertFromAPInt(Input: Result, IsSigned: IntTy->hasSignedIntegerRepresentation(),
10954	RM: llvm::APFloat::rmTowardZero);
10955	llvm::APSInt ConvertBack(S.Context.getIntWidth(T: IntTy),
10956	!IntTy->hasSignedIntegerRepresentation());
10957	bool Ignored = false;
10958	Float.convertToInteger(Result&: ConvertBack, RM: llvm::APFloat::rmNearestTiesToEven,
10959	IsExact: &Ignored);
10960	if (Result != ConvertBack)
10961	return true;
10962	} else {
10963	// Reject types that cannot be fully encoded into the mantissa of
10964	// the float.
10965	Bits = S.Context.getTypeSize(T: IntTy);
10966	unsigned FloatPrec = llvm::APFloat::semanticsPrecision(
10967	S.Context.getFloatTypeSemantics(T: FloatTy));
10968	if (Bits > FloatPrec)
10969	return true;
10970	}
10971
10972	return false;
10973	}
10974
10975	/// Attempt to convert and splat Scalar into a vector whose types matches
10976	/// Vector following GCC conversion rules. The rule is that implicit
10977	/// conversion can occur when Scalar can be casted to match Vector's element
10978	/// type without causing truncation of Scalar.
10979	static bool tryGCCVectorConvertAndSplat(Sema &S, ExprResult *Scalar,
10980	ExprResult *Vector) {
10981	QualType ScalarTy = Scalar->get()->getType().getUnqualifiedType();
10982	QualType VectorTy = Vector->get()->getType().getUnqualifiedType();
10983	QualType VectorEltTy;
10984
10985	if (const auto *VT = VectorTy->getAs<VectorType>()) {
10986	assert(!isa<ExtVectorType>(VT) &&
10987	"ExtVectorTypes should not be handled here!");
10988	VectorEltTy = VT->getElementType();
10989	} else if (VectorTy->isSveVLSBuiltinType()) {
10990	VectorEltTy =
10991	VectorTy->castAs<BuiltinType>()->getSveEltType(S.getASTContext());
10992	} else {
10993	llvm_unreachable("Only Fixed-Length and SVE Vector types are handled here");
10994	}
10995
10996	// Reject cases where the vector element type or the scalar element type are
10997	// not integral or floating point types.
10998	if (!VectorEltTy->isArithmeticType() || !ScalarTy->isArithmeticType())
10999	return true;
11000
11001	// The conversion to apply to the scalar before splatting it,
11002	// if necessary.
11003	CastKind ScalarCast = CK_NoOp;
11004
11005	// Accept cases where the vector elements are integers and the scalar is
11006	// an integer.
11007	// FIXME: Notionally if the scalar was a floating point value with a precise
11008	// integral representation, we could cast it to an appropriate integer
11009	// type and then perform the rest of the checks here. GCC will perform
11010	// this conversion in some cases as determined by the input language.
11011	// We should accept it on a language independent basis.
11012	if (VectorEltTy->isIntegralType(Ctx: S.Context) &&
11013	ScalarTy->isIntegralType(Ctx: S.Context) &&
11014	S.Context.getIntegerTypeOrder(LHS: VectorEltTy, RHS: ScalarTy)) {
11015
11016	if (canConvertIntToOtherIntTy(S, Int: Scalar, OtherIntTy: VectorEltTy))
11017	return true;
11018
11019	ScalarCast = CK_IntegralCast;
11020	} else if (VectorEltTy->isIntegralType(Ctx: S.Context) &&
11021	ScalarTy->isRealFloatingType()) {
11022	if (S.Context.getTypeSize(T: VectorEltTy) == S.Context.getTypeSize(T: ScalarTy))
11023	ScalarCast = CK_FloatingToIntegral;
11024	else
11025	return true;
11026	} else if (VectorEltTy->isRealFloatingType()) {
11027	if (ScalarTy->isRealFloatingType()) {
11028
11029	// Reject cases where the scalar type is not a constant and has a higher
11030	// Order than the vector element type.
11031	llvm::APFloat Result(0.0);
11032
11033	// Determine whether this is a constant scalar. In the event that the
11034	// value is dependent (and thus cannot be evaluated by the constant
11035	// evaluator), skip the evaluation. This will then diagnose once the
11036	// expression is instantiated.
11037	bool CstScalar = Scalar->get()->isValueDependent() ||
11038	Scalar->get()->EvaluateAsFloat(Result, Ctx: S.Context);
11039	int Order = S.Context.getFloatingTypeOrder(LHS: VectorEltTy, RHS: ScalarTy);
11040	if (!CstScalar && Order < 0)
11041	return true;
11042
11043	// If the scalar cannot be safely casted to the vector element type,
11044	// reject it.
11045	if (CstScalar) {
11046	bool Truncated = false;
11047	Result.convert(ToSemantics: S.Context.getFloatTypeSemantics(T: VectorEltTy),
11048	RM: llvm::APFloat::rmNearestTiesToEven, losesInfo: &Truncated);
11049	if (Truncated)
11050	return true;
11051	}
11052
11053	ScalarCast = CK_FloatingCast;
11054	} else if (ScalarTy->isIntegralType(Ctx: S.Context)) {
11055	if (canConvertIntTyToFloatTy(S, Int: Scalar, FloatTy: VectorEltTy))
11056	return true;
11057
11058	ScalarCast = CK_IntegralToFloating;
11059	} else
11060	return true;
11061	} else if (ScalarTy->isEnumeralType())
11062	return true;
11063
11064	// Adjust scalar if desired.
11065	if (ScalarCast != CK_NoOp)
11066	*Scalar = S.ImpCastExprToType(E: Scalar->get(), Type: VectorEltTy, CK: ScalarCast);
11067	*Scalar = S.ImpCastExprToType(E: Scalar->get(), Type: VectorTy, CK: CK_VectorSplat);
11068	return false;
11069	}
11070
11071	QualType Sema::CheckVectorOperands(ExprResult &LHS, ExprResult &RHS,
11072	SourceLocation Loc, bool IsCompAssign,
11073	bool AllowBothBool,
11074	bool AllowBoolConversions,
11075	bool AllowBoolOperation,
11076	bool ReportInvalid) {
11077	if (!IsCompAssign) {
11078	LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
11079	if (LHS.isInvalid())
11080	return QualType();
11081	}
11082	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
11083	if (RHS.isInvalid())
11084	return QualType();
11085
11086	// For conversion purposes, we ignore any qualifiers.
11087	// For example, "const float" and "float" are equivalent.
11088	QualType LHSType = LHS.get()->getType().getUnqualifiedType();
11089	QualType RHSType = RHS.get()->getType().getUnqualifiedType();
11090
11091	const VectorType *LHSVecType = LHSType->getAs<VectorType>();
11092	const VectorType *RHSVecType = RHSType->getAs<VectorType>();
11093	assert(LHSVecType || RHSVecType);
11094
11095	// AltiVec-style "vector bool op vector bool" combinations are allowed
11096	// for some operators but not others.
11097	if (!AllowBothBool && LHSVecType &&
11098	LHSVecType->getVectorKind() == VectorKind::AltiVecBool && RHSVecType &&
11099	RHSVecType->getVectorKind() == VectorKind::AltiVecBool)
11100	return ReportInvalid ? InvalidOperands(Loc, LHS, RHS) : QualType();
11101
11102	// This operation may not be performed on boolean vectors.
11103	if (!AllowBoolOperation &&
11104	(LHSType->isExtVectorBoolType() || RHSType->isExtVectorBoolType()))
11105	return ReportInvalid ? InvalidOperands(Loc, LHS, RHS) : QualType();
11106
11107	// If the vector types are identical, return.
11108	if (Context.hasSameType(T1: LHSType, T2: RHSType))
11109	return Context.getCommonSugaredType(X: LHSType, Y: RHSType);
11110
11111	// If we have compatible AltiVec and GCC vector types, use the AltiVec type.
11112	if (LHSVecType && RHSVecType &&
11113	Context.areCompatibleVectorTypes(FirstVec: LHSType, SecondVec: RHSType)) {
11114	if (isa<ExtVectorType>(Val: LHSVecType)) {
11115	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_BitCast);
11116	return LHSType;
11117	}
11118
11119	if (!IsCompAssign)
11120	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_BitCast);
11121	return RHSType;
11122	}
11123
11124	// AllowBoolConversions says that bool and non-bool AltiVec vectors
11125	// can be mixed, with the result being the non-bool type. The non-bool
11126	// operand must have integer element type.
11127	if (AllowBoolConversions && LHSVecType && RHSVecType &&
11128	LHSVecType->getNumElements() == RHSVecType->getNumElements() &&
11129	(Context.getTypeSize(T: LHSVecType->getElementType()) ==
11130	Context.getTypeSize(T: RHSVecType->getElementType()))) {
11131	if (LHSVecType->getVectorKind() == VectorKind::AltiVecVector &&
11132	LHSVecType->getElementType()->isIntegerType() &&
11133	RHSVecType->getVectorKind() == VectorKind::AltiVecBool) {
11134	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_BitCast);
11135	return LHSType;
11136	}
11137	if (!IsCompAssign &&
11138	LHSVecType->getVectorKind() == VectorKind::AltiVecBool &&
11139	RHSVecType->getVectorKind() == VectorKind::AltiVecVector &&
11140	RHSVecType->getElementType()->isIntegerType()) {
11141	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_BitCast);
11142	return RHSType;
11143	}
11144	}
11145
11146	// Expressions containing fixed-length and sizeless SVE/RVV vectors are
11147	// invalid since the ambiguity can affect the ABI.
11148	auto IsSveRVVConversion = [](QualType FirstType, QualType SecondType,
11149	unsigned &SVEorRVV) {
11150	const VectorType *VecType = SecondType->getAs<VectorType>();
11151	SVEorRVV = 0;
11152	if (FirstType->isSizelessBuiltinType() && VecType) {
11153	if (VecType->getVectorKind() == VectorKind::SveFixedLengthData ||
11154	VecType->getVectorKind() == VectorKind::SveFixedLengthPredicate)
11155	return true;
11156	if (VecType->getVectorKind() == VectorKind::RVVFixedLengthData ||
11157	VecType->getVectorKind() == VectorKind::RVVFixedLengthMask) {
11158	SVEorRVV = 1;
11159	return true;
11160	}
11161	}
11162
11163	return false;
11164	};
11165
11166	unsigned SVEorRVV;
11167	if (IsSveRVVConversion(LHSType, RHSType, SVEorRVV) ||
11168	IsSveRVVConversion(RHSType, LHSType, SVEorRVV)) {
11169	Diag(Loc, diag::err_typecheck_sve_rvv_ambiguous)
11170	<< SVEorRVV << LHSType << RHSType;
11171	return QualType();
11172	}
11173
11174	// Expressions containing GNU and SVE or RVV (fixed or sizeless) vectors are
11175	// invalid since the ambiguity can affect the ABI.
11176	auto IsSveRVVGnuConversion = [](QualType FirstType, QualType SecondType,
11177	unsigned &SVEorRVV) {
11178	const VectorType *FirstVecType = FirstType->getAs<VectorType>();
11179	const VectorType *SecondVecType = SecondType->getAs<VectorType>();
11180
11181	SVEorRVV = 0;
11182	if (FirstVecType && SecondVecType) {
11183	if (FirstVecType->getVectorKind() == VectorKind::Generic) {
11184	if (SecondVecType->getVectorKind() == VectorKind::SveFixedLengthData ||
11185	SecondVecType->getVectorKind() ==
11186	VectorKind::SveFixedLengthPredicate)
11187	return true;
11188	if (SecondVecType->getVectorKind() == VectorKind::RVVFixedLengthData ||
11189	SecondVecType->getVectorKind() == VectorKind::RVVFixedLengthMask) {
11190	SVEorRVV = 1;
11191	return true;
11192	}
11193	}
11194	return false;
11195	}
11196
11197	if (SecondVecType &&
11198	SecondVecType->getVectorKind() == VectorKind::Generic) {
11199	if (FirstType->isSVESizelessBuiltinType())
11200	return true;
11201	if (FirstType->isRVVSizelessBuiltinType()) {
11202	SVEorRVV = 1;
11203	return true;
11204	}
11205	}
11206
11207	return false;
11208	};
11209
11210	if (IsSveRVVGnuConversion(LHSType, RHSType, SVEorRVV) ||
11211	IsSveRVVGnuConversion(RHSType, LHSType, SVEorRVV)) {
11212	Diag(Loc, diag::err_typecheck_sve_rvv_gnu_ambiguous)
11213	<< SVEorRVV << LHSType << RHSType;
11214	return QualType();
11215	}
11216
11217	// If there's a vector type and a scalar, try to convert the scalar to
11218	// the vector element type and splat.
11219	unsigned DiagID = diag::err_typecheck_vector_not_convertable;
11220	if (!RHSVecType) {
11221	if (isa<ExtVectorType>(Val: LHSVecType)) {
11222	if (!tryVectorConvertAndSplat(S&: *this, scalar: &RHS, scalarTy: RHSType,
11223	vectorEltTy: LHSVecType->getElementType(), vectorTy: LHSType,
11224	DiagID))
11225	return LHSType;
11226	} else {
11227	if (!tryGCCVectorConvertAndSplat(S&: *this, Scalar: &RHS, Vector: &LHS))
11228	return LHSType;
11229	}
11230	}
11231	if (!LHSVecType) {
11232	if (isa<ExtVectorType>(Val: RHSVecType)) {
11233	if (!tryVectorConvertAndSplat(S&: *this, scalar: (IsCompAssign ? nullptr : &LHS),
11234	scalarTy: LHSType, vectorEltTy: RHSVecType->getElementType(),
11235	vectorTy: RHSType, DiagID))
11236	return RHSType;
11237	} else {
11238	if (LHS.get()->isLValue() ||
11239	!tryGCCVectorConvertAndSplat(S&: *this, Scalar: &LHS, Vector: &RHS))
11240	return RHSType;
11241	}
11242	}
11243
11244	// FIXME: The code below also handles conversion between vectors and
11245	// non-scalars, we should break this down into fine grained specific checks
11246	// and emit proper diagnostics.
11247	QualType VecType = LHSVecType ? LHSType : RHSType;
11248	const VectorType *VT = LHSVecType ? LHSVecType : RHSVecType;
11249	QualType OtherType = LHSVecType ? RHSType : LHSType;
11250	ExprResult *OtherExpr = LHSVecType ? &RHS : &LHS;
11251	if (isLaxVectorConversion(srcTy: OtherType, destTy: VecType)) {
11252	if (Context.getTargetInfo().getTriple().isPPC() &&
11253	anyAltivecTypes(RHSType, LHSType) &&
11254	!Context.areCompatibleVectorTypes(RHSType, LHSType))
11255	Diag(Loc, diag::warn_deprecated_lax_vec_conv_all) << RHSType << LHSType;
11256	// If we're allowing lax vector conversions, only the total (data) size
11257	// needs to be the same. For non compound assignment, if one of the types is
11258	// scalar, the result is always the vector type.
11259	if (!IsCompAssign) {
11260	*OtherExpr = ImpCastExprToType(E: OtherExpr->get(), Type: VecType, CK: CK_BitCast);
11261	return VecType;
11262	// In a compound assignment, lhs += rhs, 'lhs' is a lvalue src, forbidding
11263	// any implicit cast. Here, the 'rhs' should be implicit casted to 'lhs'
11264	// type. Note that this is already done by non-compound assignments in
11265	// CheckAssignmentConstraints. If it's a scalar type, only bitcast for
11266	// <1 x T> -> T. The result is also a vector type.
11267	} else if (OtherType->isExtVectorType() || OtherType->isVectorType() ||
11268	(OtherType->isScalarType() && VT->getNumElements() == 1)) {
11269	ExprResult *RHSExpr = &RHS;
11270	*RHSExpr = ImpCastExprToType(E: RHSExpr->get(), Type: LHSType, CK: CK_BitCast);
11271	return VecType;
11272	}
11273	}
11274
11275	// Okay, the expression is invalid.
11276
11277	// If there's a non-vector, non-real operand, diagnose that.
11278	if ((!RHSVecType && !RHSType->isRealType()) ||
11279	(!LHSVecType && !LHSType->isRealType())) {
11280	Diag(Loc, diag::err_typecheck_vector_not_convertable_non_scalar)
11281	<< LHSType << RHSType
11282	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
11283	return QualType();
11284	}
11285
11286	// OpenCL V1.1 6.2.6.p1:
11287	// If the operands are of more than one vector type, then an error shall
11288	// occur. Implicit conversions between vector types are not permitted, per
11289	// section 6.2.1.
11290	if (getLangOpts().OpenCL &&
11291	RHSVecType && isa<ExtVectorType>(Val: RHSVecType) &&
11292	LHSVecType && isa<ExtVectorType>(Val: LHSVecType)) {
11293	Diag(Loc, diag::err_opencl_implicit_vector_conversion) << LHSType
11294	<< RHSType;
11295	return QualType();
11296	}
11297
11298
11299	// If there is a vector type that is not a ExtVector and a scalar, we reach
11300	// this point if scalar could not be converted to the vector's element type
11301	// without truncation.
11302	if ((RHSVecType && !isa<ExtVectorType>(Val: RHSVecType)) ||
11303	(LHSVecType && !isa<ExtVectorType>(Val: LHSVecType))) {
11304	QualType Scalar = LHSVecType ? RHSType : LHSType;
11305	QualType Vector = LHSVecType ? LHSType : RHSType;
11306	unsigned ScalarOrVector = LHSVecType && RHSVecType ? 1 : 0;
11307	Diag(Loc,
11308	diag::err_typecheck_vector_not_convertable_implict_truncation)
11309	<< ScalarOrVector << Scalar << Vector;
11310
11311	return QualType();
11312	}
11313
11314	// Otherwise, use the generic diagnostic.
11315	Diag(Loc, DiagID)
11316	<< LHSType << RHSType
11317	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
11318	return QualType();
11319	}
11320
11321	QualType Sema::CheckSizelessVectorOperands(ExprResult &LHS, ExprResult &RHS,
11322	SourceLocation Loc,
11323	bool IsCompAssign,
11324	ArithConvKind OperationKind) {
11325	if (!IsCompAssign) {
11326	LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
11327	if (LHS.isInvalid())
11328	return QualType();
11329	}
11330	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
11331	if (RHS.isInvalid())
11332	return QualType();
11333
11334	QualType LHSType = LHS.get()->getType().getUnqualifiedType();
11335	QualType RHSType = RHS.get()->getType().getUnqualifiedType();
11336
11337	const BuiltinType *LHSBuiltinTy = LHSType->getAs<BuiltinType>();
11338	const BuiltinType *RHSBuiltinTy = RHSType->getAs<BuiltinType>();
11339
11340	unsigned DiagID = diag::err_typecheck_invalid_operands;
11341	if ((OperationKind == ACK_Arithmetic) &&
11342	((LHSBuiltinTy && LHSBuiltinTy->isSVEBool()) ||
11343	(RHSBuiltinTy && RHSBuiltinTy->isSVEBool()))) {
11344	Diag(Loc, DiagID) << LHSType << RHSType << LHS.get()->getSourceRange()
11345	<< RHS.get()->getSourceRange();
11346	return QualType();
11347	}
11348
11349	if (Context.hasSameType(T1: LHSType, T2: RHSType))
11350	return LHSType;
11351
11352	if (LHSType->isSveVLSBuiltinType() && !RHSType->isSveVLSBuiltinType()) {
11353	if (!tryGCCVectorConvertAndSplat(S&: *this, Scalar: &RHS, Vector: &LHS))
11354	return LHSType;
11355	}
11356	if (RHSType->isSveVLSBuiltinType() && !LHSType->isSveVLSBuiltinType()) {
11357	if (LHS.get()->isLValue() ||
11358	!tryGCCVectorConvertAndSplat(S&: *this, Scalar: &LHS, Vector: &RHS))
11359	return RHSType;
11360	}
11361
11362	if ((!LHSType->isSveVLSBuiltinType() && !LHSType->isRealType()) ||
11363	(!RHSType->isSveVLSBuiltinType() && !RHSType->isRealType())) {
11364	Diag(Loc, diag::err_typecheck_vector_not_convertable_non_scalar)
11365	<< LHSType << RHSType << LHS.get()->getSourceRange()
11366	<< RHS.get()->getSourceRange();
11367	return QualType();
11368	}
11369
11370	if (LHSType->isSveVLSBuiltinType() && RHSType->isSveVLSBuiltinType() &&
11371	Context.getBuiltinVectorTypeInfo(VecTy: LHSBuiltinTy).EC !=
11372	Context.getBuiltinVectorTypeInfo(VecTy: RHSBuiltinTy).EC) {
11373	Diag(Loc, diag::err_typecheck_vector_lengths_not_equal)
11374	<< LHSType << RHSType << LHS.get()->getSourceRange()
11375	<< RHS.get()->getSourceRange();
11376	return QualType();
11377	}
11378
11379	if (LHSType->isSveVLSBuiltinType() || RHSType->isSveVLSBuiltinType()) {
11380	QualType Scalar = LHSType->isSveVLSBuiltinType() ? RHSType : LHSType;
11381	QualType Vector = LHSType->isSveVLSBuiltinType() ? LHSType : RHSType;
11382	bool ScalarOrVector =
11383	LHSType->isSveVLSBuiltinType() && RHSType->isSveVLSBuiltinType();
11384
11385	Diag(Loc, diag::err_typecheck_vector_not_convertable_implict_truncation)
11386	<< ScalarOrVector << Scalar << Vector;
11387
11388	return QualType();
11389	}
11390
11391	Diag(Loc, DiagID) << LHSType << RHSType << LHS.get()->getSourceRange()
11392	<< RHS.get()->getSourceRange();
11393	return QualType();
11394	}
11395
11396	// checkArithmeticNull - Detect when a NULL constant is used improperly in an
11397	// expression. These are mainly cases where the null pointer is used as an
11398	// integer instead of a pointer.
11399	static void checkArithmeticNull(Sema &S, ExprResult &LHS, ExprResult &RHS,
11400	SourceLocation Loc, bool IsCompare) {
11401	// The canonical way to check for a GNU null is with isNullPointerConstant,
11402	// but we use a bit of a hack here for speed; this is a relatively
11403	// hot path, and isNullPointerConstant is slow.
11404	bool LHSNull = isa<GNUNullExpr>(Val: LHS.get()->IgnoreParenImpCasts());
11405	bool RHSNull = isa<GNUNullExpr>(Val: RHS.get()->IgnoreParenImpCasts());
11406
11407	QualType NonNullType = LHSNull ? RHS.get()->getType() : LHS.get()->getType();
11408
11409	// Avoid analyzing cases where the result will either be invalid (and
11410	// diagnosed as such) or entirely valid and not something to warn about.
11411	if ((!LHSNull && !RHSNull) || NonNullType->isBlockPointerType() ||
11412	NonNullType->isMemberPointerType() || NonNullType->isFunctionType())
11413	return;
11414
11415	// Comparison operations would not make sense with a null pointer no matter
11416	// what the other expression is.
11417	if (!IsCompare) {
11418	S.Diag(Loc, diag::warn_null_in_arithmetic_operation)
11419	<< (LHSNull ? LHS.get()->getSourceRange() : SourceRange())
11420	<< (RHSNull ? RHS.get()->getSourceRange() : SourceRange());
11421	return;
11422	}
11423
11424	// The rest of the operations only make sense with a null pointer
11425	// if the other expression is a pointer.
11426	if (LHSNull == RHSNull || NonNullType->isAnyPointerType() ||
11427	NonNullType->canDecayToPointerType())
11428	return;
11429
11430	S.Diag(Loc, diag::warn_null_in_comparison_operation)
11431	<< LHSNull /* LHS is NULL */ << NonNullType
11432	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
11433	}
11434
11435	static void DiagnoseDivisionSizeofPointerOrArray(Sema &S, Expr *LHS, Expr *RHS,
11436	SourceLocation Loc) {
11437	const auto *LUE = dyn_cast<UnaryExprOrTypeTraitExpr>(Val: LHS);
11438	const auto *RUE = dyn_cast<UnaryExprOrTypeTraitExpr>(Val: RHS);
11439	if (!LUE || !RUE)
11440	return;
11441	if (LUE->getKind() != UETT_SizeOf || LUE->isArgumentType() ||
11442	RUE->getKind() != UETT_SizeOf)
11443	return;
11444
11445	const Expr *LHSArg = LUE->getArgumentExpr()->IgnoreParens();
11446	QualType LHSTy = LHSArg->getType();
11447	QualType RHSTy;
11448
11449	if (RUE->isArgumentType())
11450	RHSTy = RUE->getArgumentType().getNonReferenceType();
11451	else
11452	RHSTy = RUE->getArgumentExpr()->IgnoreParens()->getType();
11453
11454	if (LHSTy->isPointerType() && !RHSTy->isPointerType()) {
11455	if (!S.Context.hasSameUnqualifiedType(T1: LHSTy->getPointeeType(), T2: RHSTy))
11456	return;
11457
11458	S.Diag(Loc, diag::warn_division_sizeof_ptr) << LHS << LHS->getSourceRange();
11459	if (const auto *DRE = dyn_cast<DeclRefExpr>(Val: LHSArg)) {
11460	if (const ValueDecl *LHSArgDecl = DRE->getDecl())
11461	S.Diag(LHSArgDecl->getLocation(), diag::note_pointer_declared_here)
11462	<< LHSArgDecl;
11463	}
11464	} else if (const auto *ArrayTy = S.Context.getAsArrayType(T: LHSTy)) {
11465	QualType ArrayElemTy = ArrayTy->getElementType();
11466	if (ArrayElemTy != S.Context.getBaseElementType(VAT: ArrayTy) ||
11467	ArrayElemTy->isDependentType() || RHSTy->isDependentType() ||
11468	RHSTy->isReferenceType() || ArrayElemTy->isCharType() ||
11469	S.Context.getTypeSize(T: ArrayElemTy) == S.Context.getTypeSize(T: RHSTy))
11470	return;
11471	S.Diag(Loc, diag::warn_division_sizeof_array)
11472	<< LHSArg->getSourceRange() << ArrayElemTy << RHSTy;
11473	if (const auto *DRE = dyn_cast<DeclRefExpr>(Val: LHSArg)) {
11474	if (const ValueDecl *LHSArgDecl = DRE->getDecl())
11475	S.Diag(LHSArgDecl->getLocation(), diag::note_array_declared_here)
11476	<< LHSArgDecl;
11477	}
11478
11479	S.Diag(Loc, diag::note_precedence_silence) << RHS;
11480	}
11481	}
11482
11483	static void DiagnoseBadDivideOrRemainderValues(Sema& S, ExprResult &LHS,
11484	ExprResult &RHS,
11485	SourceLocation Loc, bool IsDiv) {
11486	// Check for division/remainder by zero.
11487	Expr::EvalResult RHSValue;
11488	if (!RHS.get()->isValueDependent() &&
11489	RHS.get()->EvaluateAsInt(RHSValue, S.Context) &&
11490	RHSValue.Val.getInt() == 0)
11491	S.DiagRuntimeBehavior(Loc, RHS.get(),
11492	S.PDiag(diag::warn_remainder_division_by_zero)
11493	<< IsDiv << RHS.get()->getSourceRange());
11494	}
11495
11496	QualType Sema::CheckMultiplyDivideOperands(ExprResult &LHS, ExprResult &RHS,
11497	SourceLocation Loc,
11498	bool IsCompAssign, bool IsDiv) {
11499	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
11500
11501	QualType LHSTy = LHS.get()->getType();
11502	QualType RHSTy = RHS.get()->getType();
11503	if (LHSTy->isVectorType() || RHSTy->isVectorType())
11504	return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
11505	/*AllowBothBool*/ getLangOpts().AltiVec,
11506	/*AllowBoolConversions*/ false,
11507	/*AllowBooleanOperation*/ AllowBoolOperation: false,
11508	/*ReportInvalid*/ true);
11509	if (LHSTy->isSveVLSBuiltinType() || RHSTy->isSveVLSBuiltinType())
11510	return CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign,
11511	OperationKind: ACK_Arithmetic);
11512	if (!IsDiv &&
11513	(LHSTy->isConstantMatrixType() || RHSTy->isConstantMatrixType()))
11514	return CheckMatrixMultiplyOperands(LHS, RHS, Loc, IsCompAssign);
11515	// For division, only matrix-by-scalar is supported. Other combinations with
11516	// matrix types are invalid.
11517	if (IsDiv && LHSTy->isConstantMatrixType() && RHSTy->isArithmeticType())
11518	return CheckMatrixElementwiseOperands(LHS, RHS, Loc, IsCompAssign);
11519
11520	QualType compType = UsualArithmeticConversions(
11521	LHS, RHS, Loc, ACK: IsCompAssign ? ACK_CompAssign : ACK_Arithmetic);
11522	if (LHS.isInvalid() || RHS.isInvalid())
11523	return QualType();
11524
11525
11526	if (compType.isNull() || !compType->isArithmeticType())
11527	return InvalidOperands(Loc, LHS, RHS);
11528	if (IsDiv) {
11529	DiagnoseBadDivideOrRemainderValues(S&: *this, LHS, RHS, Loc, IsDiv);
11530	DiagnoseDivisionSizeofPointerOrArray(S&: *this, LHS: LHS.get(), RHS: RHS.get(), Loc);
11531	}
11532	return compType;
11533	}
11534
11535	QualType Sema::CheckRemainderOperands(
11536	ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) {
11537	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
11538
11539	if (LHS.get()->getType()->isVectorType() ||
11540	RHS.get()->getType()->isVectorType()) {
11541	if (LHS.get()->getType()->hasIntegerRepresentation() &&
11542	RHS.get()->getType()->hasIntegerRepresentation())
11543	return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
11544	/*AllowBothBool*/ getLangOpts().AltiVec,
11545	/*AllowBoolConversions*/ false,
11546	/*AllowBooleanOperation*/ AllowBoolOperation: false,
11547	/*ReportInvalid*/ true);
11548	return InvalidOperands(Loc, LHS, RHS);
11549	}
11550
11551	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
11552	RHS.get()->getType()->isSveVLSBuiltinType()) {
11553	if (LHS.get()->getType()->hasIntegerRepresentation() &&
11554	RHS.get()->getType()->hasIntegerRepresentation())
11555	return CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign,
11556	OperationKind: ACK_Arithmetic);
11557
11558	return InvalidOperands(Loc, LHS, RHS);
11559	}
11560
11561	QualType compType = UsualArithmeticConversions(
11562	LHS, RHS, Loc, ACK: IsCompAssign ? ACK_CompAssign : ACK_Arithmetic);
11563	if (LHS.isInvalid() || RHS.isInvalid())
11564	return QualType();
11565
11566	if (compType.isNull() || !compType->isIntegerType())
11567	return InvalidOperands(Loc, LHS, RHS);
11568	DiagnoseBadDivideOrRemainderValues(S&: *this, LHS, RHS, Loc, IsDiv: false /* IsDiv */);
11569	return compType;
11570	}
11571
11572	/// Diagnose invalid arithmetic on two void pointers.
11573	static void diagnoseArithmeticOnTwoVoidPointers(Sema &S, SourceLocation Loc,
11574	Expr *LHSExpr, Expr *RHSExpr) {
11575	S.Diag(Loc, S.getLangOpts().CPlusPlus
11576	? diag::err_typecheck_pointer_arith_void_type
11577	: diag::ext_gnu_void_ptr)
11578	<< 1 /* two pointers */ << LHSExpr->getSourceRange()
11579	<< RHSExpr->getSourceRange();
11580	}
11581
11582	/// Diagnose invalid arithmetic on a void pointer.
11583	static void diagnoseArithmeticOnVoidPointer(Sema &S, SourceLocation Loc,
11584	Expr *Pointer) {
11585	S.Diag(Loc, S.getLangOpts().CPlusPlus
11586	? diag::err_typecheck_pointer_arith_void_type
11587	: diag::ext_gnu_void_ptr)
11588	<< 0 /* one pointer */ << Pointer->getSourceRange();
11589	}
11590
11591	/// Diagnose invalid arithmetic on a null pointer.
11592	///
11593	/// If \p IsGNUIdiom is true, the operation is using the 'p = (i8*)nullptr + n'
11594	/// idiom, which we recognize as a GNU extension.
11595	///
11596	static void diagnoseArithmeticOnNullPointer(Sema &S, SourceLocation Loc,
11597	Expr *Pointer, bool IsGNUIdiom) {
11598	if (IsGNUIdiom)
11599	S.Diag(Loc, diag::warn_gnu_null_ptr_arith)
11600	<< Pointer->getSourceRange();
11601	else
11602	S.Diag(Loc, diag::warn_pointer_arith_null_ptr)
11603	<< S.getLangOpts().CPlusPlus << Pointer->getSourceRange();
11604	}
11605
11606	/// Diagnose invalid subraction on a null pointer.
11607	///
11608	static void diagnoseSubtractionOnNullPointer(Sema &S, SourceLocation Loc,
11609	Expr *Pointer, bool BothNull) {
11610	// Null - null is valid in C++ [expr.add]p7
11611	if (BothNull && S.getLangOpts().CPlusPlus)
11612	return;
11613
11614	// Is this s a macro from a system header?
11615	if (S.Diags.getSuppressSystemWarnings() && S.SourceMgr.isInSystemMacro(loc: Loc))
11616	return;
11617
11618	S.DiagRuntimeBehavior(Loc, Pointer,
11619	S.PDiag(diag::warn_pointer_sub_null_ptr)
11620	<< S.getLangOpts().CPlusPlus
11621	<< Pointer->getSourceRange());
11622	}
11623
11624	/// Diagnose invalid arithmetic on two function pointers.
11625	static void diagnoseArithmeticOnTwoFunctionPointers(Sema &S, SourceLocation Loc,
11626	Expr *LHS, Expr *RHS) {
11627	assert(LHS->getType()->isAnyPointerType());
11628	assert(RHS->getType()->isAnyPointerType());
11629	S.Diag(Loc, S.getLangOpts().CPlusPlus
11630	? diag::err_typecheck_pointer_arith_function_type
11631	: diag::ext_gnu_ptr_func_arith)
11632	<< 1 /* two pointers */ << LHS->getType()->getPointeeType()
11633	// We only show the second type if it differs from the first.
11634	<< (unsigned)!S.Context.hasSameUnqualifiedType(LHS->getType(),
11635	RHS->getType())
11636	<< RHS->getType()->getPointeeType()
11637	<< LHS->getSourceRange() << RHS->getSourceRange();
11638	}
11639
11640	/// Diagnose invalid arithmetic on a function pointer.
11641	static void diagnoseArithmeticOnFunctionPointer(Sema &S, SourceLocation Loc,
11642	Expr *Pointer) {
11643	assert(Pointer->getType()->isAnyPointerType());
11644	S.Diag(Loc, S.getLangOpts().CPlusPlus
11645	? diag::err_typecheck_pointer_arith_function_type
11646	: diag::ext_gnu_ptr_func_arith)
11647	<< 0 /* one pointer */ << Pointer->getType()->getPointeeType()
11648	<< 0 /* one pointer, so only one type */
11649	<< Pointer->getSourceRange();
11650	}
11651
11652	/// Emit error if Operand is incomplete pointer type
11653	///
11654	/// \returns True if pointer has incomplete type
11655	static bool checkArithmeticIncompletePointerType(Sema &S, SourceLocation Loc,
11656	Expr *Operand) {
11657	QualType ResType = Operand->getType();
11658	if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
11659	ResType = ResAtomicType->getValueType();
11660
11661	assert(ResType->isAnyPointerType() && !ResType->isDependentType());
11662	QualType PointeeTy = ResType->getPointeeType();
11663	return S.RequireCompleteSizedType(
11664	Loc, PointeeTy,
11665	diag::err_typecheck_arithmetic_incomplete_or_sizeless_type,
11666	Operand->getSourceRange());
11667	}
11668
11669	/// Check the validity of an arithmetic pointer operand.
11670	///
11671	/// If the operand has pointer type, this code will check for pointer types
11672	/// which are invalid in arithmetic operations. These will be diagnosed
11673	/// appropriately, including whether or not the use is supported as an
11674	/// extension.
11675	///
11676	/// \returns True when the operand is valid to use (even if as an extension).
11677	static bool checkArithmeticOpPointerOperand(Sema &S, SourceLocation Loc,
11678	Expr *Operand) {
11679	QualType ResType = Operand->getType();
11680	if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
11681	ResType = ResAtomicType->getValueType();
11682
11683	if (!ResType->isAnyPointerType()) return true;
11684
11685	QualType PointeeTy = ResType->getPointeeType();
11686	if (PointeeTy->isVoidType()) {
11687	diagnoseArithmeticOnVoidPointer(S, Loc, Pointer: Operand);
11688	return !S.getLangOpts().CPlusPlus;
11689	}
11690	if (PointeeTy->isFunctionType()) {
11691	diagnoseArithmeticOnFunctionPointer(S, Loc, Pointer: Operand);
11692	return !S.getLangOpts().CPlusPlus;
11693	}
11694
11695	if (checkArithmeticIncompletePointerType(S, Loc, Operand)) return false;
11696
11697	return true;
11698	}
11699
11700	/// Check the validity of a binary arithmetic operation w.r.t. pointer
11701	/// operands.
11702	///
11703	/// This routine will diagnose any invalid arithmetic on pointer operands much
11704	/// like \see checkArithmeticOpPointerOperand. However, it has special logic
11705	/// for emitting a single diagnostic even for operations where both LHS and RHS
11706	/// are (potentially problematic) pointers.
11707	///
11708	/// \returns True when the operand is valid to use (even if as an extension).
11709	static bool checkArithmeticBinOpPointerOperands(Sema &S, SourceLocation Loc,
11710	Expr *LHSExpr, Expr *RHSExpr) {
11711	bool isLHSPointer = LHSExpr->getType()->isAnyPointerType();
11712	bool isRHSPointer = RHSExpr->getType()->isAnyPointerType();
11713	if (!isLHSPointer && !isRHSPointer) return true;
11714
11715	QualType LHSPointeeTy, RHSPointeeTy;
11716	if (isLHSPointer) LHSPointeeTy = LHSExpr->getType()->getPointeeType();
11717	if (isRHSPointer) RHSPointeeTy = RHSExpr->getType()->getPointeeType();
11718
11719	// if both are pointers check if operation is valid wrt address spaces
11720	if (isLHSPointer && isRHSPointer) {
11721	if (!LHSPointeeTy.isAddressSpaceOverlapping(T: RHSPointeeTy)) {
11722	S.Diag(Loc,
11723	diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
11724	<< LHSExpr->getType() << RHSExpr->getType() << 1 /*arithmetic op*/
11725	<< LHSExpr->getSourceRange() << RHSExpr->getSourceRange();
11726	return false;
11727	}
11728	}
11729
11730	// Check for arithmetic on pointers to incomplete types.
11731	bool isLHSVoidPtr = isLHSPointer && LHSPointeeTy->isVoidType();
11732	bool isRHSVoidPtr = isRHSPointer && RHSPointeeTy->isVoidType();
11733	if (isLHSVoidPtr || isRHSVoidPtr) {
11734	if (!isRHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, Pointer: LHSExpr);
11735	else if (!isLHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, Pointer: RHSExpr);
11736	else diagnoseArithmeticOnTwoVoidPointers(S, Loc, LHSExpr, RHSExpr);
11737
11738	return !S.getLangOpts().CPlusPlus;
11739	}
11740
11741	bool isLHSFuncPtr = isLHSPointer && LHSPointeeTy->isFunctionType();
11742	bool isRHSFuncPtr = isRHSPointer && RHSPointeeTy->isFunctionType();
11743	if (isLHSFuncPtr || isRHSFuncPtr) {
11744	if (!isRHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, Pointer: LHSExpr);
11745	else if (!isLHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc,
11746	Pointer: RHSExpr);
11747	else diagnoseArithmeticOnTwoFunctionPointers(S, Loc, LHS: LHSExpr, RHS: RHSExpr);
11748
11749	return !S.getLangOpts().CPlusPlus;
11750	}
11751
11752	if (isLHSPointer && checkArithmeticIncompletePointerType(S, Loc, Operand: LHSExpr))
11753	return false;
11754	if (isRHSPointer && checkArithmeticIncompletePointerType(S, Loc, Operand: RHSExpr))
11755	return false;
11756
11757	return true;
11758	}
11759
11760	/// diagnoseStringPlusInt - Emit a warning when adding an integer to a string
11761	/// literal.
11762	static void diagnoseStringPlusInt(Sema &Self, SourceLocation OpLoc,
11763	Expr *LHSExpr, Expr *RHSExpr) {
11764	StringLiteral* StrExpr = dyn_cast<StringLiteral>(Val: LHSExpr->IgnoreImpCasts());
11765	Expr* IndexExpr = RHSExpr;
11766	if (!StrExpr) {
11767	StrExpr = dyn_cast<StringLiteral>(Val: RHSExpr->IgnoreImpCasts());
11768	IndexExpr = LHSExpr;
11769	}
11770
11771	bool IsStringPlusInt = StrExpr &&
11772	IndexExpr->getType()->isIntegralOrUnscopedEnumerationType();
11773	if (!IsStringPlusInt || IndexExpr->isValueDependent())
11774	return;
11775
11776	SourceRange DiagRange(LHSExpr->getBeginLoc(), RHSExpr->getEndLoc());
11777	Self.Diag(OpLoc, diag::warn_string_plus_int)
11778	<< DiagRange << IndexExpr->IgnoreImpCasts()->getType();
11779
11780	// Only print a fixit for "str" + int, not for int + "str".
11781	if (IndexExpr == RHSExpr) {
11782	SourceLocation EndLoc = Self.getLocForEndOfToken(Loc: RHSExpr->getEndLoc());
11783	Self.Diag(OpLoc, diag::note_string_plus_scalar_silence)
11784	<< FixItHint::CreateInsertion(LHSExpr->getBeginLoc(), "&")
11785	<< FixItHint::CreateReplacement(SourceRange(OpLoc), "[")
11786	<< FixItHint::CreateInsertion(EndLoc, "]");
11787	} else
11788	Self.Diag(OpLoc, diag::note_string_plus_scalar_silence);
11789	}
11790
11791	/// Emit a warning when adding a char literal to a string.
11792	static void diagnoseStringPlusChar(Sema &Self, SourceLocation OpLoc,
11793	Expr *LHSExpr, Expr *RHSExpr) {
11794	const Expr *StringRefExpr = LHSExpr;
11795	const CharacterLiteral *CharExpr =
11796	dyn_cast<CharacterLiteral>(Val: RHSExpr->IgnoreImpCasts());
11797
11798	if (!CharExpr) {
11799	CharExpr = dyn_cast<CharacterLiteral>(Val: LHSExpr->IgnoreImpCasts());
11800	StringRefExpr = RHSExpr;
11801	}
11802
11803	if (!CharExpr || !StringRefExpr)
11804	return;
11805
11806	const QualType StringType = StringRefExpr->getType();
11807
11808	// Return if not a PointerType.
11809	if (!StringType->isAnyPointerType())
11810	return;
11811
11812	// Return if not a CharacterType.
11813	if (!StringType->getPointeeType()->isAnyCharacterType())
11814	return;
11815
11816	ASTContext &Ctx = Self.getASTContext();
11817	SourceRange DiagRange(LHSExpr->getBeginLoc(), RHSExpr->getEndLoc());
11818
11819	const QualType CharType = CharExpr->getType();
11820	if (!CharType->isAnyCharacterType() &&
11821	CharType->isIntegerType() &&
11822	llvm::isUIntN(N: Ctx.getCharWidth(), x: CharExpr->getValue())) {
11823	Self.Diag(OpLoc, diag::warn_string_plus_char)
11824	<< DiagRange << Ctx.CharTy;
11825	} else {
11826	Self.Diag(OpLoc, diag::warn_string_plus_char)
11827	<< DiagRange << CharExpr->getType();
11828	}
11829
11830	// Only print a fixit for str + char, not for char + str.
11831	if (isa<CharacterLiteral>(Val: RHSExpr->IgnoreImpCasts())) {
11832	SourceLocation EndLoc = Self.getLocForEndOfToken(Loc: RHSExpr->getEndLoc());
11833	Self.Diag(OpLoc, diag::note_string_plus_scalar_silence)
11834	<< FixItHint::CreateInsertion(LHSExpr->getBeginLoc(), "&")
11835	<< FixItHint::CreateReplacement(SourceRange(OpLoc), "[")
11836	<< FixItHint::CreateInsertion(EndLoc, "]");
11837	} else {
11838	Self.Diag(OpLoc, diag::note_string_plus_scalar_silence);
11839	}
11840	}
11841
11842	/// Emit error when two pointers are incompatible.
11843	static void diagnosePointerIncompatibility(Sema &S, SourceLocation Loc,
11844	Expr *LHSExpr, Expr *RHSExpr) {
11845	assert(LHSExpr->getType()->isAnyPointerType());
11846	assert(RHSExpr->getType()->isAnyPointerType());
11847	S.Diag(Loc, diag::err_typecheck_sub_ptr_compatible)
11848	<< LHSExpr->getType() << RHSExpr->getType() << LHSExpr->getSourceRange()
11849	<< RHSExpr->getSourceRange();
11850	}
11851
11852	// C99 6.5.6
11853	QualType Sema::CheckAdditionOperands(ExprResult &LHS, ExprResult &RHS,
11854	SourceLocation Loc, BinaryOperatorKind Opc,
11855	QualType* CompLHSTy) {
11856	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
11857
11858	if (LHS.get()->getType()->isVectorType() ||
11859	RHS.get()->getType()->isVectorType()) {
11860	QualType compType =
11861	CheckVectorOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy,
11862	/*AllowBothBool*/ getLangOpts().AltiVec,
11863	/*AllowBoolConversions*/ getLangOpts().ZVector,
11864	/*AllowBooleanOperation*/ AllowBoolOperation: false,
11865	/*ReportInvalid*/ true);
11866	if (CompLHSTy) *CompLHSTy = compType;
11867	return compType;
11868	}
11869
11870	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
11871	RHS.get()->getType()->isSveVLSBuiltinType()) {
11872	QualType compType =
11873	CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy, OperationKind: ACK_Arithmetic);
11874	if (CompLHSTy)
11875	*CompLHSTy = compType;
11876	return compType;
11877	}
11878
11879	if (LHS.get()->getType()->isConstantMatrixType() ||
11880	RHS.get()->getType()->isConstantMatrixType()) {
11881	QualType compType =
11882	CheckMatrixElementwiseOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy);
11883	if (CompLHSTy)
11884	*CompLHSTy = compType;
11885	return compType;
11886	}
11887
11888	QualType compType = UsualArithmeticConversions(
11889	LHS, RHS, Loc, ACK: CompLHSTy ? ACK_CompAssign : ACK_Arithmetic);
11890	if (LHS.isInvalid() || RHS.isInvalid())
11891	return QualType();
11892
11893	// Diagnose "string literal" '+' int and string '+' "char literal".
11894	if (Opc == BO_Add) {
11895	diagnoseStringPlusInt(Self&: *this, OpLoc: Loc, LHSExpr: LHS.get(), RHSExpr: RHS.get());
11896	diagnoseStringPlusChar(Self&: *this, OpLoc: Loc, LHSExpr: LHS.get(), RHSExpr: RHS.get());
11897	}
11898
11899	// handle the common case first (both operands are arithmetic).
11900	if (!compType.isNull() && compType->isArithmeticType()) {
11901	if (CompLHSTy) *CompLHSTy = compType;
11902	return compType;
11903	}
11904
11905	// Type-checking. Ultimately the pointer's going to be in PExp;
11906	// note that we bias towards the LHS being the pointer.
11907	Expr *PExp = LHS.get(), *IExp = RHS.get();
11908
11909	bool isObjCPointer;
11910	if (PExp->getType()->isPointerType()) {
11911	isObjCPointer = false;
11912	} else if (PExp->getType()->isObjCObjectPointerType()) {
11913	isObjCPointer = true;
11914	} else {
11915	std::swap(a&: PExp, b&: IExp);
11916	if (PExp->getType()->isPointerType()) {
11917	isObjCPointer = false;
11918	} else if (PExp->getType()->isObjCObjectPointerType()) {
11919	isObjCPointer = true;
11920	} else {
11921	return InvalidOperands(Loc, LHS, RHS);
11922	}
11923	}
11924	assert(PExp->getType()->isAnyPointerType());
11925
11926	if (!IExp->getType()->isIntegerType())
11927	return InvalidOperands(Loc, LHS, RHS);
11928
11929	// Adding to a null pointer results in undefined behavior.
11930	if (PExp->IgnoreParenCasts()->isNullPointerConstant(
11931	Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNotNull)) {
11932	// In C++ adding zero to a null pointer is defined.
11933	Expr::EvalResult KnownVal;
11934	if (!getLangOpts().CPlusPlus ||
11935	(!IExp->isValueDependent() &&
11936	(!IExp->EvaluateAsInt(Result&: KnownVal, Ctx: Context) ||
11937	KnownVal.Val.getInt() != 0))) {
11938	// Check the conditions to see if this is the 'p = nullptr + n' idiom.
11939	bool IsGNUIdiom = BinaryOperator::isNullPointerArithmeticExtension(
11940	Ctx&: Context, Opc: BO_Add, LHS: PExp, RHS: IExp);
11941	diagnoseArithmeticOnNullPointer(S&: *this, Loc, Pointer: PExp, IsGNUIdiom);
11942	}
11943	}
11944
11945	if (!checkArithmeticOpPointerOperand(S&: *this, Loc, Operand: PExp))
11946	return QualType();
11947
11948	if (isObjCPointer && checkArithmeticOnObjCPointer(S&: *this, opLoc: Loc, op: PExp))
11949	return QualType();
11950
11951	// Check array bounds for pointer arithemtic
11952	CheckArrayAccess(BaseExpr: PExp, IndexExpr: IExp);
11953
11954	if (CompLHSTy) {
11955	QualType LHSTy = Context.isPromotableBitField(E: LHS.get());
11956	if (LHSTy.isNull()) {
11957	LHSTy = LHS.get()->getType();
11958	if (Context.isPromotableIntegerType(T: LHSTy))
11959	LHSTy = Context.getPromotedIntegerType(PromotableType: LHSTy);
11960	}
11961	*CompLHSTy = LHSTy;
11962	}
11963
11964	return PExp->getType();
11965	}
11966
11967	// C99 6.5.6
11968	QualType Sema::CheckSubtractionOperands(ExprResult &LHS, ExprResult &RHS,
11969	SourceLocation Loc,
11970	QualType* CompLHSTy) {
11971	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
11972
11973	if (LHS.get()->getType()->isVectorType() ||
11974	RHS.get()->getType()->isVectorType()) {
11975	QualType compType =
11976	CheckVectorOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy,
11977	/*AllowBothBool*/ getLangOpts().AltiVec,
11978	/*AllowBoolConversions*/ getLangOpts().ZVector,
11979	/*AllowBooleanOperation*/ AllowBoolOperation: false,
11980	/*ReportInvalid*/ true);
11981	if (CompLHSTy) *CompLHSTy = compType;
11982	return compType;
11983	}
11984
11985	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
11986	RHS.get()->getType()->isSveVLSBuiltinType()) {
11987	QualType compType =
11988	CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy, OperationKind: ACK_Arithmetic);
11989	if (CompLHSTy)
11990	*CompLHSTy = compType;
11991	return compType;
11992	}
11993
11994	if (LHS.get()->getType()->isConstantMatrixType() ||
11995	RHS.get()->getType()->isConstantMatrixType()) {
11996	QualType compType =
11997	CheckMatrixElementwiseOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy);
11998	if (CompLHSTy)
11999	*CompLHSTy = compType;
12000	return compType;
12001	}
12002
12003	QualType compType = UsualArithmeticConversions(
12004	LHS, RHS, Loc, ACK: CompLHSTy ? ACK_CompAssign : ACK_Arithmetic);
12005	if (LHS.isInvalid() || RHS.isInvalid())
12006	return QualType();
12007
12008	// Enforce type constraints: C99 6.5.6p3.
12009
12010	// Handle the common case first (both operands are arithmetic).
12011	if (!compType.isNull() && compType->isArithmeticType()) {
12012	if (CompLHSTy) *CompLHSTy = compType;
12013	return compType;
12014	}
12015
12016	// Either ptr - int or ptr - ptr.
12017	if (LHS.get()->getType()->isAnyPointerType()) {
12018	QualType lpointee = LHS.get()->getType()->getPointeeType();
12019
12020	// Diagnose bad cases where we step over interface counts.
12021	if (LHS.get()->getType()->isObjCObjectPointerType() &&
12022	checkArithmeticOnObjCPointer(S&: *this, opLoc: Loc, op: LHS.get()))
12023	return QualType();
12024
12025	// The result type of a pointer-int computation is the pointer type.
12026	if (RHS.get()->getType()->isIntegerType()) {
12027	// Subtracting from a null pointer should produce a warning.
12028	// The last argument to the diagnose call says this doesn't match the
12029	// GNU int-to-pointer idiom.
12030	if (LHS.get()->IgnoreParenCasts()->isNullPointerConstant(Ctx&: Context,
12031	NPC: Expr::NPC_ValueDependentIsNotNull)) {
12032	// In C++ adding zero to a null pointer is defined.
12033	Expr::EvalResult KnownVal;
12034	if (!getLangOpts().CPlusPlus ||
12035	(!RHS.get()->isValueDependent() &&
12036	(!RHS.get()->EvaluateAsInt(Result&: KnownVal, Ctx: Context) ||
12037	KnownVal.Val.getInt() != 0))) {
12038	diagnoseArithmeticOnNullPointer(S&: *this, Loc, Pointer: LHS.get(), IsGNUIdiom: false);
12039	}
12040	}
12041
12042	if (!checkArithmeticOpPointerOperand(S&: *this, Loc, Operand: LHS.get()))
12043	return QualType();
12044
12045	// Check array bounds for pointer arithemtic
12046	CheckArrayAccess(BaseExpr: LHS.get(), IndexExpr: RHS.get(), /*ArraySubscriptExpr*/ASE: nullptr,
12047	/*AllowOnePastEnd*/true, /*IndexNegated*/true);
12048
12049	if (CompLHSTy) *CompLHSTy = LHS.get()->getType();
12050	return LHS.get()->getType();
12051	}
12052
12053	// Handle pointer-pointer subtractions.
12054	if (const PointerType *RHSPTy
12055	= RHS.get()->getType()->getAs<PointerType>()) {
12056	QualType rpointee = RHSPTy->getPointeeType();
12057
12058	if (getLangOpts().CPlusPlus) {
12059	// Pointee types must be the same: C++ [expr.add]
12060	if (!Context.hasSameUnqualifiedType(T1: lpointee, T2: rpointee)) {
12061	diagnosePointerIncompatibility(S&: *this, Loc, LHSExpr: LHS.get(), RHSExpr: RHS.get());
12062	}
12063	} else {
12064	// Pointee types must be compatible C99 6.5.6p3
12065	if (!Context.typesAreCompatible(
12066	T1: Context.getCanonicalType(T: lpointee).getUnqualifiedType(),
12067	T2: Context.getCanonicalType(T: rpointee).getUnqualifiedType())) {
12068	diagnosePointerIncompatibility(S&: *this, Loc, LHSExpr: LHS.get(), RHSExpr: RHS.get());
12069	return QualType();
12070	}
12071	}
12072
12073	if (!checkArithmeticBinOpPointerOperands(S&: *this, Loc,
12074	LHSExpr: LHS.get(), RHSExpr: RHS.get()))
12075	return QualType();
12076
12077	bool LHSIsNullPtr = LHS.get()->IgnoreParenCasts()->isNullPointerConstant(
12078	Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNotNull);
12079	bool RHSIsNullPtr = RHS.get()->IgnoreParenCasts()->isNullPointerConstant(
12080	Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNotNull);
12081
12082	// Subtracting nullptr or from nullptr is suspect
12083	if (LHSIsNullPtr)
12084	diagnoseSubtractionOnNullPointer(S&: *this, Loc, Pointer: LHS.get(), BothNull: RHSIsNullPtr);
12085	if (RHSIsNullPtr)
12086	diagnoseSubtractionOnNullPointer(S&: *this, Loc, Pointer: RHS.get(), BothNull: LHSIsNullPtr);
12087
12088	// The pointee type may have zero size. As an extension, a structure or
12089	// union may have zero size or an array may have zero length. In this
12090	// case subtraction does not make sense.
12091	if (!rpointee->isVoidType() && !rpointee->isFunctionType()) {
12092	CharUnits ElementSize = Context.getTypeSizeInChars(T: rpointee);
12093	if (ElementSize.isZero()) {
12094	Diag(Loc,diag::warn_sub_ptr_zero_size_types)
12095	<< rpointee.getUnqualifiedType()
12096	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
12097	}
12098	}
12099
12100	if (CompLHSTy) *CompLHSTy = LHS.get()->getType();
12101	return Context.getPointerDiffType();
12102	}
12103	}
12104
12105	return InvalidOperands(Loc, LHS, RHS);
12106	}
12107
12108	static bool isScopedEnumerationType(QualType T) {
12109	if (const EnumType *ET = T->getAs<EnumType>())
12110	return ET->getDecl()->isScoped();
12111	return false;
12112	}
12113
12114	static void DiagnoseBadShiftValues(Sema& S, ExprResult &LHS, ExprResult &RHS,
12115	SourceLocation Loc, BinaryOperatorKind Opc,
12116	QualType LHSType) {
12117	// OpenCL 6.3j: shift values are effectively % word size of LHS (more defined),
12118	// so skip remaining warnings as we don't want to modify values within Sema.
12119	if (S.getLangOpts().OpenCL)
12120	return;
12121
12122	// Check right/shifter operand
12123	Expr::EvalResult RHSResult;
12124	if (RHS.get()->isValueDependent() ||
12125	!RHS.get()->EvaluateAsInt(Result&: RHSResult, Ctx: S.Context))
12126	return;
12127	llvm::APSInt Right = RHSResult.Val.getInt();
12128
12129	if (Right.isNegative()) {
12130	S.DiagRuntimeBehavior(Loc, RHS.get(),
12131	S.PDiag(diag::warn_shift_negative)
12132	<< RHS.get()->getSourceRange());
12133	return;
12134	}
12135
12136	QualType LHSExprType = LHS.get()->getType();
12137	uint64_t LeftSize = S.Context.getTypeSize(T: LHSExprType);
12138	if (LHSExprType->isBitIntType())
12139	LeftSize = S.Context.getIntWidth(T: LHSExprType);
12140	else if (LHSExprType->isFixedPointType()) {
12141	auto FXSema = S.Context.getFixedPointSemantics(Ty: LHSExprType);
12142	LeftSize = FXSema.getWidth() - (unsigned)FXSema.hasUnsignedPadding();
12143	}
12144	if (Right.uge(RHS: LeftSize)) {
12145	S.DiagRuntimeBehavior(Loc, RHS.get(),
12146	S.PDiag(diag::warn_shift_gt_typewidth)
12147	<< RHS.get()->getSourceRange());
12148	return;
12149	}
12150
12151	// FIXME: We probably need to handle fixed point types specially here.
12152	if (Opc != BO_Shl || LHSExprType->isFixedPointType())
12153	return;
12154
12155	// When left shifting an ICE which is signed, we can check for overflow which
12156	// according to C++ standards prior to C++2a has undefined behavior
12157	// ([expr.shift] 5.8/2). Unsigned integers have defined behavior modulo one
12158	// more than the maximum value representable in the result type, so never
12159	// warn for those. (FIXME: Unsigned left-shift overflow in a constant
12160	// expression is still probably a bug.)
12161	Expr::EvalResult LHSResult;
12162	if (LHS.get()->isValueDependent() ||
12163	LHSType->hasUnsignedIntegerRepresentation() ||
12164	!LHS.get()->EvaluateAsInt(Result&: LHSResult, Ctx: S.Context))
12165	return;
12166	llvm::APSInt Left = LHSResult.Val.getInt();
12167
12168	// Don't warn if signed overflow is defined, then all the rest of the
12169	// diagnostics will not be triggered because the behavior is defined.
12170	// Also don't warn in C++20 mode (and newer), as signed left shifts
12171	// always wrap and never overflow.
12172	if (S.getLangOpts().isSignedOverflowDefined() || S.getLangOpts().CPlusPlus20)
12173	return;
12174
12175	// If LHS does not have a non-negative value then, the
12176	// behavior is undefined before C++2a. Warn about it.
12177	if (Left.isNegative()) {
12178	S.DiagRuntimeBehavior(Loc, LHS.get(),
12179	S.PDiag(diag::warn_shift_lhs_negative)
12180	<< LHS.get()->getSourceRange());
12181	return;
12182	}
12183
12184	llvm::APInt ResultBits =
12185	static_cast<llvm::APInt &>(Right) + Left.getSignificantBits();
12186	if (ResultBits.ule(RHS: LeftSize))
12187	return;
12188	llvm::APSInt Result = Left.extend(width: ResultBits.getLimitedValue());
12189	Result = Result.shl(ShiftAmt: Right);
12190
12191	// Print the bit representation of the signed integer as an unsigned
12192	// hexadecimal number.
12193	SmallString<40> HexResult;
12194	Result.toString(Str&: HexResult, Radix: 16, /*Signed =*/false, /*Literal =*/formatAsCLiteral: true);
12195
12196	// If we are only missing a sign bit, this is less likely to result in actual
12197	// bugs -- if the result is cast back to an unsigned type, it will have the
12198	// expected value. Thus we place this behind a different warning that can be
12199	// turned off separately if needed.
12200	if (ResultBits - 1 == LeftSize) {
12201	S.Diag(Loc, diag::warn_shift_result_sets_sign_bit)
12202	<< HexResult << LHSType
12203	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
12204	return;
12205	}
12206
12207	S.Diag(Loc, diag::warn_shift_result_gt_typewidth)
12208	<< HexResult.str() << Result.getSignificantBits() << LHSType
12209	<< Left.getBitWidth() << LHS.get()->getSourceRange()
12210	<< RHS.get()->getSourceRange();
12211	}
12212
12213	/// Return the resulting type when a vector is shifted
12214	/// by a scalar or vector shift amount.
12215	static QualType checkVectorShift(Sema &S, ExprResult &LHS, ExprResult &RHS,
12216	SourceLocation Loc, bool IsCompAssign) {
12217	// OpenCL v1.1 s6.3.j says RHS can be a vector only if LHS is a vector.
12218	if ((S.LangOpts.OpenCL || S.LangOpts.ZVector) &&
12219	!LHS.get()->getType()->isVectorType()) {
12220	S.Diag(Loc, diag::err_shift_rhs_only_vector)
12221	<< RHS.get()->getType() << LHS.get()->getType()
12222	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
12223	return QualType();
12224	}
12225
12226	if (!IsCompAssign) {
12227	LHS = S.UsualUnaryConversions(E: LHS.get());
12228	if (LHS.isInvalid()) return QualType();
12229	}
12230
12231	RHS = S.UsualUnaryConversions(E: RHS.get());
12232	if (RHS.isInvalid()) return QualType();
12233
12234	QualType LHSType = LHS.get()->getType();
12235	// Note that LHS might be a scalar because the routine calls not only in
12236	// OpenCL case.
12237	const VectorType *LHSVecTy = LHSType->getAs<VectorType>();
12238	QualType LHSEleType = LHSVecTy ? LHSVecTy->getElementType() : LHSType;
12239
12240	// Note that RHS might not be a vector.
12241	QualType RHSType = RHS.get()->getType();
12242	const VectorType *RHSVecTy = RHSType->getAs<VectorType>();
12243	QualType RHSEleType = RHSVecTy ? RHSVecTy->getElementType() : RHSType;
12244
12245	// Do not allow shifts for boolean vectors.
12246	if ((LHSVecTy && LHSVecTy->isExtVectorBoolType()) ||
12247	(RHSVecTy && RHSVecTy->isExtVectorBoolType())) {
12248	S.Diag(Loc, diag::err_typecheck_invalid_operands)
12249	<< LHS.get()->getType() << RHS.get()->getType()
12250	<< LHS.get()->getSourceRange();
12251	return QualType();
12252	}
12253
12254	// The operands need to be integers.
12255	if (!LHSEleType->isIntegerType()) {
12256	S.Diag(Loc, diag::err_typecheck_expect_int)
12257	<< LHS.get()->getType() << LHS.get()->getSourceRange();
12258	return QualType();
12259	}
12260
12261	if (!RHSEleType->isIntegerType()) {
12262	S.Diag(Loc, diag::err_typecheck_expect_int)
12263	<< RHS.get()->getType() << RHS.get()->getSourceRange();
12264	return QualType();
12265	}
12266
12267	if (!LHSVecTy) {
12268	assert(RHSVecTy);
12269	if (IsCompAssign)
12270	return RHSType;
12271	if (LHSEleType != RHSEleType) {
12272	LHS = S.ImpCastExprToType(E: LHS.get(),Type: RHSEleType, CK: CK_IntegralCast);
12273	LHSEleType = RHSEleType;
12274	}
12275	QualType VecTy =
12276	S.Context.getExtVectorType(VectorType: LHSEleType, NumElts: RHSVecTy->getNumElements());
12277	LHS = S.ImpCastExprToType(E: LHS.get(), Type: VecTy, CK: CK_VectorSplat);
12278	LHSType = VecTy;
12279	} else if (RHSVecTy) {
12280	// OpenCL v1.1 s6.3.j says that for vector types, the operators
12281	// are applied component-wise. So if RHS is a vector, then ensure
12282	// that the number of elements is the same as LHS...
12283	if (RHSVecTy->getNumElements() != LHSVecTy->getNumElements()) {
12284	S.Diag(Loc, diag::err_typecheck_vector_lengths_not_equal)
12285	<< LHS.get()->getType() << RHS.get()->getType()
12286	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
12287	return QualType();
12288	}
12289	if (!S.LangOpts.OpenCL && !S.LangOpts.ZVector) {
12290	const BuiltinType *LHSBT = LHSEleType->getAs<clang::BuiltinType>();
12291	const BuiltinType *RHSBT = RHSEleType->getAs<clang::BuiltinType>();
12292	if (LHSBT != RHSBT &&
12293	S.Context.getTypeSize(LHSBT) != S.Context.getTypeSize(RHSBT)) {
12294	S.Diag(Loc, diag::warn_typecheck_vector_element_sizes_not_equal)
12295	<< LHS.get()->getType() << RHS.get()->getType()
12296	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
12297	}
12298	}
12299	} else {
12300	// ...else expand RHS to match the number of elements in LHS.
12301	QualType VecTy =
12302	S.Context.getExtVectorType(VectorType: RHSEleType, NumElts: LHSVecTy->getNumElements());
12303	RHS = S.ImpCastExprToType(E: RHS.get(), Type: VecTy, CK: CK_VectorSplat);
12304	}
12305
12306	return LHSType;
12307	}
12308
12309	static QualType checkSizelessVectorShift(Sema &S, ExprResult &LHS,
12310	ExprResult &RHS, SourceLocation Loc,
12311	bool IsCompAssign) {
12312	if (!IsCompAssign) {
12313	LHS = S.UsualUnaryConversions(E: LHS.get());
12314	if (LHS.isInvalid())
12315	return QualType();
12316	}
12317
12318	RHS = S.UsualUnaryConversions(E: RHS.get());
12319	if (RHS.isInvalid())
12320	return QualType();
12321
12322	QualType LHSType = LHS.get()->getType();
12323	const BuiltinType *LHSBuiltinTy = LHSType->castAs<BuiltinType>();
12324	QualType LHSEleType = LHSType->isSveVLSBuiltinType()
12325	? LHSBuiltinTy->getSveEltType(S.getASTContext())
12326	: LHSType;
12327
12328	// Note that RHS might not be a vector
12329	QualType RHSType = RHS.get()->getType();
12330	const BuiltinType *RHSBuiltinTy = RHSType->castAs<BuiltinType>();
12331	QualType RHSEleType = RHSType->isSveVLSBuiltinType()
12332	? RHSBuiltinTy->getSveEltType(S.getASTContext())
12333	: RHSType;
12334
12335	if ((LHSBuiltinTy && LHSBuiltinTy->isSVEBool()) ||
12336	(RHSBuiltinTy && RHSBuiltinTy->isSVEBool())) {
12337	S.Diag(Loc, diag::err_typecheck_invalid_operands)
12338	<< LHSType << RHSType << LHS.get()->getSourceRange();
12339	return QualType();
12340	}
12341
12342	if (!LHSEleType->isIntegerType()) {
12343	S.Diag(Loc, diag::err_typecheck_expect_int)
12344	<< LHS.get()->getType() << LHS.get()->getSourceRange();
12345	return QualType();
12346	}
12347
12348	if (!RHSEleType->isIntegerType()) {
12349	S.Diag(Loc, diag::err_typecheck_expect_int)
12350	<< RHS.get()->getType() << RHS.get()->getSourceRange();
12351	return QualType();
12352	}
12353
12354	if (LHSType->isSveVLSBuiltinType() && RHSType->isSveVLSBuiltinType() &&
12355	(S.Context.getBuiltinVectorTypeInfo(VecTy: LHSBuiltinTy).EC !=
12356	S.Context.getBuiltinVectorTypeInfo(VecTy: RHSBuiltinTy).EC)) {
12357	S.Diag(Loc, diag::err_typecheck_invalid_operands)
12358	<< LHSType << RHSType << LHS.get()->getSourceRange()
12359	<< RHS.get()->getSourceRange();
12360	return QualType();
12361	}
12362
12363	if (!LHSType->isSveVLSBuiltinType()) {
12364	assert(RHSType->isSveVLSBuiltinType());
12365	if (IsCompAssign)
12366	return RHSType;
12367	if (LHSEleType != RHSEleType) {
12368	LHS = S.ImpCastExprToType(E: LHS.get(), Type: RHSEleType, CK: clang::CK_IntegralCast);
12369	LHSEleType = RHSEleType;
12370	}
12371	const llvm::ElementCount VecSize =
12372	S.Context.getBuiltinVectorTypeInfo(VecTy: RHSBuiltinTy).EC;
12373	QualType VecTy =
12374	S.Context.getScalableVectorType(EltTy: LHSEleType, NumElts: VecSize.getKnownMinValue());
12375	LHS = S.ImpCastExprToType(E: LHS.get(), Type: VecTy, CK: clang::CK_VectorSplat);
12376	LHSType = VecTy;
12377	} else if (RHSBuiltinTy && RHSBuiltinTy->isSveVLSBuiltinType()) {
12378	if (S.Context.getTypeSize(RHSBuiltinTy) !=
12379	S.Context.getTypeSize(LHSBuiltinTy)) {
12380	S.Diag(Loc, diag::err_typecheck_vector_lengths_not_equal)
12381	<< LHSType << RHSType << LHS.get()->getSourceRange()
12382	<< RHS.get()->getSourceRange();
12383	return QualType();
12384	}
12385	} else {
12386	const llvm::ElementCount VecSize =
12387	S.Context.getBuiltinVectorTypeInfo(VecTy: LHSBuiltinTy).EC;
12388	if (LHSEleType != RHSEleType) {
12389	RHS = S.ImpCastExprToType(E: RHS.get(), Type: LHSEleType, CK: clang::CK_IntegralCast);
12390	RHSEleType = LHSEleType;
12391	}
12392	QualType VecTy =
12393	S.Context.getScalableVectorType(EltTy: RHSEleType, NumElts: VecSize.getKnownMinValue());
12394	RHS = S.ImpCastExprToType(E: RHS.get(), Type: VecTy, CK: CK_VectorSplat);
12395	}
12396
12397	return LHSType;
12398	}
12399
12400	// C99 6.5.7
12401	QualType Sema::CheckShiftOperands(ExprResult &LHS, ExprResult &RHS,
12402	SourceLocation Loc, BinaryOperatorKind Opc,
12403	bool IsCompAssign) {
12404	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
12405
12406	// Vector shifts promote their scalar inputs to vector type.
12407	if (LHS.get()->getType()->isVectorType() ||
12408	RHS.get()->getType()->isVectorType()) {
12409	if (LangOpts.ZVector) {
12410	// The shift operators for the z vector extensions work basically
12411	// like general shifts, except that neither the LHS nor the RHS is
12412	// allowed to be a "vector bool".
12413	if (auto LHSVecType = LHS.get()->getType()->getAs<VectorType>())
12414	if (LHSVecType->getVectorKind() == VectorKind::AltiVecBool)
12415	return InvalidOperands(Loc, LHS, RHS);
12416	if (auto RHSVecType = RHS.get()->getType()->getAs<VectorType>())
12417	if (RHSVecType->getVectorKind() == VectorKind::AltiVecBool)
12418	return InvalidOperands(Loc, LHS, RHS);
12419	}
12420	return checkVectorShift(S&: *this, LHS, RHS, Loc, IsCompAssign);
12421	}
12422
12423	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
12424	RHS.get()->getType()->isSveVLSBuiltinType())
12425	return checkSizelessVectorShift(S&: *this, LHS, RHS, Loc, IsCompAssign);
12426
12427	// Shifts don't perform usual arithmetic conversions, they just do integer
12428	// promotions on each operand. C99 6.5.7p3
12429
12430	// For the LHS, do usual unary conversions, but then reset them away
12431	// if this is a compound assignment.
12432	ExprResult OldLHS = LHS;
12433	LHS = UsualUnaryConversions(E: LHS.get());
12434	if (LHS.isInvalid())
12435	return QualType();
12436	QualType LHSType = LHS.get()->getType();
12437	if (IsCompAssign) LHS = OldLHS;
12438
12439	// The RHS is simpler.
12440	RHS = UsualUnaryConversions(E: RHS.get());
12441	if (RHS.isInvalid())
12442	return QualType();
12443	QualType RHSType = RHS.get()->getType();
12444
12445	// C99 6.5.7p2: Each of the operands shall have integer type.
12446	// Embedded-C 4.1.6.2.2: The LHS may also be fixed-point.
12447	if ((!LHSType->isFixedPointOrIntegerType() &&
12448	!LHSType->hasIntegerRepresentation()) ||
12449	!RHSType->hasIntegerRepresentation())
12450	return InvalidOperands(Loc, LHS, RHS);
12451
12452	// C++0x: Don't allow scoped enums. FIXME: Use something better than
12453	// hasIntegerRepresentation() above instead of this.
12454	if (isScopedEnumerationType(T: LHSType) ||
12455	isScopedEnumerationType(T: RHSType)) {
12456	return InvalidOperands(Loc, LHS, RHS);
12457	}
12458	DiagnoseBadShiftValues(S&: *this, LHS, RHS, Loc, Opc, LHSType);
12459
12460	// "The type of the result is that of the promoted left operand."
12461	return LHSType;
12462	}
12463
12464	/// Diagnose bad pointer comparisons.
12465	static void diagnoseDistinctPointerComparison(Sema &S, SourceLocation Loc,
12466	ExprResult &LHS, ExprResult &RHS,
12467	bool IsError) {
12468	S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_distinct_pointers
12469	: diag::ext_typecheck_comparison_of_distinct_pointers)
12470	<< LHS.get()->getType() << RHS.get()->getType()
12471	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
12472	}
12473
12474	/// Returns false if the pointers are converted to a composite type,
12475	/// true otherwise.
12476	static bool convertPointersToCompositeType(Sema &S, SourceLocation Loc,
12477	ExprResult &LHS, ExprResult &RHS) {
12478	// C++ [expr.rel]p2:
12479	// [...] Pointer conversions (4.10) and qualification
12480	// conversions (4.4) are performed on pointer operands (or on
12481	// a pointer operand and a null pointer constant) to bring
12482	// them to their composite pointer type. [...]
12483	//
12484	// C++ [expr.eq]p1 uses the same notion for (in)equality
12485	// comparisons of pointers.
12486
12487	QualType LHSType = LHS.get()->getType();
12488	QualType RHSType = RHS.get()->getType();
12489	assert(LHSType->isPointerType() || RHSType->isPointerType() ||
12490	LHSType->isMemberPointerType() || RHSType->isMemberPointerType());
12491
12492	QualType T = S.FindCompositePointerType(Loc, E1&: LHS, E2&: RHS);
12493	if (T.isNull()) {
12494	if ((LHSType->isAnyPointerType() || LHSType->isMemberPointerType()) &&
12495	(RHSType->isAnyPointerType() || RHSType->isMemberPointerType()))
12496	diagnoseDistinctPointerComparison(S, Loc, LHS, RHS, /*isError*/IsError: true);
12497	else
12498	S.InvalidOperands(Loc, LHS, RHS);
12499	return true;
12500	}
12501
12502	return false;
12503	}
12504
12505	static void diagnoseFunctionPointerToVoidComparison(Sema &S, SourceLocation Loc,
12506	ExprResult &LHS,
12507	ExprResult &RHS,
12508	bool IsError) {
12509	S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_fptr_to_void
12510	: diag::ext_typecheck_comparison_of_fptr_to_void)
12511	<< LHS.get()->getType() << RHS.get()->getType()
12512	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
12513	}
12514
12515	static bool isObjCObjectLiteral(ExprResult &E) {
12516	switch (E.get()->IgnoreParenImpCasts()->getStmtClass()) {
12517	case Stmt::ObjCArrayLiteralClass:
12518	case Stmt::ObjCDictionaryLiteralClass:
12519	case Stmt::ObjCStringLiteralClass:
12520	case Stmt::ObjCBoxedExprClass:
12521	return true;
12522	default:
12523	// Note that ObjCBoolLiteral is NOT an object literal!
12524	return false;
12525	}
12526	}
12527
12528	static bool hasIsEqualMethod(Sema &S, const Expr *LHS, const Expr *RHS) {
12529	const ObjCObjectPointerType *Type =
12530	LHS->getType()->getAs<ObjCObjectPointerType>();
12531
12532	// If this is not actually an Objective-C object, bail out.
12533	if (!Type)
12534	return false;
12535
12536	// Get the LHS object's interface type.
12537	QualType InterfaceType = Type->getPointeeType();
12538
12539	// If the RHS isn't an Objective-C object, bail out.
12540	if (!RHS->getType()->isObjCObjectPointerType())
12541	return false;
12542
12543	// Try to find the -isEqual: method.
12544	Selector IsEqualSel = S.NSAPIObj->getIsEqualSelector();
12545	ObjCMethodDecl *Method = S.LookupMethodInObjectType(Sel: IsEqualSel,
12546	Ty: InterfaceType,
12547	/*IsInstance=*/true);
12548	if (!Method) {
12549	if (Type->isObjCIdType()) {
12550	// For 'id', just check the global pool.
12551	Method = S.LookupInstanceMethodInGlobalPool(Sel: IsEqualSel, R: SourceRange(),
12552	/*receiverId=*/receiverIdOrClass: true);
12553	} else {
12554	// Check protocols.
12555	Method = S.LookupMethodInQualifiedType(Sel: IsEqualSel, OPT: Type,
12556	/*IsInstance=*/true);
12557	}
12558	}
12559
12560	if (!Method)
12561	return false;
12562
12563	QualType T = Method->parameters()[0]->getType();
12564	if (!T->isObjCObjectPointerType())
12565	return false;
12566
12567	QualType R = Method->getReturnType();
12568	if (!R->isScalarType())
12569	return false;
12570
12571	return true;
12572	}
12573
12574	Sema::ObjCLiteralKind Sema::CheckLiteralKind(Expr *FromE) {
12575	FromE = FromE->IgnoreParenImpCasts();
12576	switch (FromE->getStmtClass()) {
12577	default:
12578	break;
12579	case Stmt::ObjCStringLiteralClass:
12580	// "string literal"
12581	return LK_String;
12582	case Stmt::ObjCArrayLiteralClass:
12583	// "array literal"
12584	return LK_Array;
12585	case Stmt::ObjCDictionaryLiteralClass:
12586	// "dictionary literal"
12587	return LK_Dictionary;
12588	case Stmt::BlockExprClass:
12589	return LK_Block;
12590	case Stmt::ObjCBoxedExprClass: {
12591	Expr *Inner = cast<ObjCBoxedExpr>(Val: FromE)->getSubExpr()->IgnoreParens();
12592	switch (Inner->getStmtClass()) {
12593	case Stmt::IntegerLiteralClass:
12594	case Stmt::FloatingLiteralClass:
12595	case Stmt::CharacterLiteralClass:
12596	case Stmt::ObjCBoolLiteralExprClass:
12597	case Stmt::CXXBoolLiteralExprClass:
12598	// "numeric literal"
12599	return LK_Numeric;
12600	case Stmt::ImplicitCastExprClass: {
12601	CastKind CK = cast<CastExpr>(Val: Inner)->getCastKind();
12602	// Boolean literals can be represented by implicit casts.
12603	if (CK == CK_IntegralToBoolean || CK == CK_IntegralCast)
12604	return LK_Numeric;
12605	break;
12606	}
12607	default:
12608	break;
12609	}
12610	return LK_Boxed;
12611	}
12612	}
12613	return LK_None;
12614	}
12615
12616	static void diagnoseObjCLiteralComparison(Sema &S, SourceLocation Loc,
12617	ExprResult &LHS, ExprResult &RHS,
12618	BinaryOperator::Opcode Opc){
12619	Expr *Literal;
12620	Expr *Other;
12621	if (isObjCObjectLiteral(E&: LHS)) {
12622	Literal = LHS.get();
12623	Other = RHS.get();
12624	} else {
12625	Literal = RHS.get();
12626	Other = LHS.get();
12627	}
12628
12629	// Don't warn on comparisons against nil.
12630	Other = Other->IgnoreParenCasts();
12631	if (Other->isNullPointerConstant(Ctx&: S.getASTContext(),
12632	NPC: Expr::NPC_ValueDependentIsNotNull))
12633	return;
12634
12635	// This should be kept in sync with warn_objc_literal_comparison.
12636	// LK_String should always be after the other literals, since it has its own
12637	// warning flag.
12638	Sema::ObjCLiteralKind LiteralKind = S.CheckLiteralKind(FromE: Literal);
12639	assert(LiteralKind != Sema::LK_Block);
12640	if (LiteralKind == Sema::LK_None) {
12641	llvm_unreachable("Unknown Objective-C object literal kind");
12642	}
12643
12644	if (LiteralKind == Sema::LK_String)
12645	S.Diag(Loc, diag::warn_objc_string_literal_comparison)
12646	<< Literal->getSourceRange();
12647	else
12648	S.Diag(Loc, diag::warn_objc_literal_comparison)
12649	<< LiteralKind << Literal->getSourceRange();
12650
12651	if (BinaryOperator::isEqualityOp(Opc) &&
12652	hasIsEqualMethod(S, LHS: LHS.get(), RHS: RHS.get())) {
12653	SourceLocation Start = LHS.get()->getBeginLoc();
12654	SourceLocation End = S.getLocForEndOfToken(Loc: RHS.get()->getEndLoc());
12655	CharSourceRange OpRange =
12656	CharSourceRange::getCharRange(B: Loc, E: S.getLocForEndOfToken(Loc));
12657
12658	S.Diag(Loc, diag::note_objc_literal_comparison_isequal)
12659	<< FixItHint::CreateInsertion(Start, Opc == BO_EQ ? "[" : "![")
12660	<< FixItHint::CreateReplacement(OpRange, " isEqual:")
12661	<< FixItHint::CreateInsertion(End, "]");
12662	}
12663	}
12664
12665	/// Warns on !x < y, !x & y where !(x < y), !(x & y) was probably intended.
12666	static void diagnoseLogicalNotOnLHSofCheck(Sema &S, ExprResult &LHS,
12667	ExprResult &RHS, SourceLocation Loc,
12668	BinaryOperatorKind Opc) {
12669	// Check that left hand side is !something.
12670	UnaryOperator *UO = dyn_cast<UnaryOperator>(Val: LHS.get()->IgnoreImpCasts());
12671	if (!UO || UO->getOpcode() != UO_LNot) return;
12672
12673	// Only check if the right hand side is non-bool arithmetic type.
12674	if (RHS.get()->isKnownToHaveBooleanValue()) return;
12675
12676	// Make sure that the something in !something is not bool.
12677	Expr *SubExpr = UO->getSubExpr()->IgnoreImpCasts();
12678	if (SubExpr->isKnownToHaveBooleanValue()) return;
12679
12680	// Emit warning.
12681	bool IsBitwiseOp = Opc == BO_And || Opc == BO_Or || Opc == BO_Xor;
12682	S.Diag(UO->getOperatorLoc(), diag::warn_logical_not_on_lhs_of_check)
12683	<< Loc << IsBitwiseOp;
12684
12685	// First note suggest !(x < y)
12686	SourceLocation FirstOpen = SubExpr->getBeginLoc();
12687	SourceLocation FirstClose = RHS.get()->getEndLoc();
12688	FirstClose = S.getLocForEndOfToken(Loc: FirstClose);
12689	if (FirstClose.isInvalid())
12690	FirstOpen = SourceLocation();
12691	S.Diag(UO->getOperatorLoc(), diag::note_logical_not_fix)
12692	<< IsBitwiseOp
12693	<< FixItHint::CreateInsertion(FirstOpen, "(")
12694	<< FixItHint::CreateInsertion(FirstClose, ")");
12695
12696	// Second note suggests (!x) < y
12697	SourceLocation SecondOpen = LHS.get()->getBeginLoc();
12698	SourceLocation SecondClose = LHS.get()->getEndLoc();
12699	SecondClose = S.getLocForEndOfToken(Loc: SecondClose);
12700	if (SecondClose.isInvalid())
12701	SecondOpen = SourceLocation();
12702	S.Diag(UO->getOperatorLoc(), diag::note_logical_not_silence_with_parens)
12703	<< FixItHint::CreateInsertion(SecondOpen, "(")
12704	<< FixItHint::CreateInsertion(SecondClose, ")");
12705	}
12706
12707	// Returns true if E refers to a non-weak array.
12708	static bool checkForArray(const Expr *E) {
12709	const ValueDecl *D = nullptr;
12710	if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(Val: E)) {
12711	D = DR->getDecl();
12712	} else if (const MemberExpr *Mem = dyn_cast<MemberExpr>(Val: E)) {
12713	if (Mem->isImplicitAccess())
12714	D = Mem->getMemberDecl();
12715	}
12716	if (!D)
12717	return false;
12718	return D->getType()->isArrayType() && !D->isWeak();
12719	}
12720
12721	/// Diagnose some forms of syntactically-obvious tautological comparison.
12722	static void diagnoseTautologicalComparison(Sema &S, SourceLocation Loc,
12723	Expr *LHS, Expr *RHS,
12724	BinaryOperatorKind Opc) {
12725	Expr *LHSStripped = LHS->IgnoreParenImpCasts();
12726	Expr *RHSStripped = RHS->IgnoreParenImpCasts();
12727
12728	QualType LHSType = LHS->getType();
12729	QualType RHSType = RHS->getType();
12730	if (LHSType->hasFloatingRepresentation() ||
12731	(LHSType->isBlockPointerType() && !BinaryOperator::isEqualityOp(Opc)) ||
12732	S.inTemplateInstantiation())
12733	return;
12734
12735	// WebAssembly Tables cannot be compared, therefore shouldn't emit
12736	// Tautological diagnostics.
12737	if (LHSType->isWebAssemblyTableType() || RHSType->isWebAssemblyTableType())
12738	return;
12739
12740	// Comparisons between two array types are ill-formed for operator<=>, so
12741	// we shouldn't emit any additional warnings about it.
12742	if (Opc == BO_Cmp && LHSType->isArrayType() && RHSType->isArrayType())
12743	return;
12744
12745	// For non-floating point types, check for self-comparisons of the form
12746	// x == x, x != x, x < x, etc. These always evaluate to a constant, and
12747	// often indicate logic errors in the program.
12748	//
12749	// NOTE: Don't warn about comparison expressions resulting from macro
12750	// expansion. Also don't warn about comparisons which are only self
12751	// comparisons within a template instantiation. The warnings should catch
12752	// obvious cases in the definition of the template anyways. The idea is to
12753	// warn when the typed comparison operator will always evaluate to the same
12754	// result.
12755
12756	// Used for indexing into %select in warn_comparison_always
12757	enum {
12758	AlwaysConstant,
12759	AlwaysTrue,
12760	AlwaysFalse,
12761	AlwaysEqual, // std::strong_ordering::equal from operator<=>
12762	};
12763
12764	// C++2a [depr.array.comp]:
12765	// Equality and relational comparisons ([expr.eq], [expr.rel]) between two
12766	// operands of array type are deprecated.
12767	if (S.getLangOpts().CPlusPlus20 && LHSStripped->getType()->isArrayType() &&
12768	RHSStripped->getType()->isArrayType()) {
12769	S.Diag(Loc, diag::warn_depr_array_comparison)
12770	<< LHS->getSourceRange() << RHS->getSourceRange()
12771	<< LHSStripped->getType() << RHSStripped->getType();
12772	// Carry on to produce the tautological comparison warning, if this
12773	// expression is potentially-evaluated, we can resolve the array to a
12774	// non-weak declaration, and so on.
12775	}
12776
12777	if (!LHS->getBeginLoc().isMacroID() && !RHS->getBeginLoc().isMacroID()) {
12778	if (Expr::isSameComparisonOperand(E1: LHS, E2: RHS)) {
12779	unsigned Result;
12780	switch (Opc) {
12781	case BO_EQ:
12782	case BO_LE:
12783	case BO_GE:
12784	Result = AlwaysTrue;
12785	break;
12786	case BO_NE:
12787	case BO_LT:
12788	case BO_GT:
12789	Result = AlwaysFalse;
12790	break;
12791	case BO_Cmp:
12792	Result = AlwaysEqual;
12793	break;
12794	default:
12795	Result = AlwaysConstant;
12796	break;
12797	}
12798	S.DiagRuntimeBehavior(Loc, nullptr,
12799	S.PDiag(diag::warn_comparison_always)
12800	<< 0 /*self-comparison*/
12801	<< Result);
12802	} else if (checkForArray(E: LHSStripped) && checkForArray(E: RHSStripped)) {
12803	// What is it always going to evaluate to?
12804	unsigned Result;
12805	switch (Opc) {
12806	case BO_EQ: // e.g. array1 == array2
12807	Result = AlwaysFalse;
12808	break;
12809	case BO_NE: // e.g. array1 != array2
12810	Result = AlwaysTrue;
12811	break;
12812	default: // e.g. array1 <= array2
12813	// The best we can say is 'a constant'
12814	Result = AlwaysConstant;
12815	break;
12816	}
12817	S.DiagRuntimeBehavior(Loc, nullptr,
12818	S.PDiag(diag::warn_comparison_always)
12819	<< 1 /*array comparison*/
12820	<< Result);
12821	}
12822	}
12823
12824	if (isa<CastExpr>(Val: LHSStripped))
12825	LHSStripped = LHSStripped->IgnoreParenCasts();
12826	if (isa<CastExpr>(Val: RHSStripped))
12827	RHSStripped = RHSStripped->IgnoreParenCasts();
12828
12829	// Warn about comparisons against a string constant (unless the other
12830	// operand is null); the user probably wants string comparison function.
12831	Expr *LiteralString = nullptr;
12832	Expr *LiteralStringStripped = nullptr;
12833	if ((isa<StringLiteral>(Val: LHSStripped) || isa<ObjCEncodeExpr>(Val: LHSStripped)) &&
12834	!RHSStripped->isNullPointerConstant(Ctx&: S.Context,
12835	NPC: Expr::NPC_ValueDependentIsNull)) {
12836	LiteralString = LHS;
12837	LiteralStringStripped = LHSStripped;
12838	} else if ((isa<StringLiteral>(Val: RHSStripped) ||
12839	isa<ObjCEncodeExpr>(Val: RHSStripped)) &&
12840	!LHSStripped->isNullPointerConstant(Ctx&: S.Context,
12841	NPC: Expr::NPC_ValueDependentIsNull)) {
12842	LiteralString = RHS;
12843	LiteralStringStripped = RHSStripped;
12844	}
12845
12846	if (LiteralString) {
12847	S.DiagRuntimeBehavior(Loc, nullptr,
12848	S.PDiag(diag::warn_stringcompare)
12849	<< isa<ObjCEncodeExpr>(LiteralStringStripped)
12850	<< LiteralString->getSourceRange());
12851	}
12852	}
12853
12854	static ImplicitConversionKind castKindToImplicitConversionKind(CastKind CK) {
12855	switch (CK) {
12856	default: {
12857	#ifndef NDEBUG
12858	llvm::errs() << "unhandled cast kind: " << CastExpr::getCastKindName(CK)
12859	<< "\n";
12860	#endif
12861	llvm_unreachable("unhandled cast kind");
12862	}
12863	case CK_UserDefinedConversion:
12864	return ICK_Identity;
12865	case CK_LValueToRValue:
12866	return ICK_Lvalue_To_Rvalue;
12867	case CK_ArrayToPointerDecay:
12868	return ICK_Array_To_Pointer;
12869	case CK_FunctionToPointerDecay:
12870	return ICK_Function_To_Pointer;
12871	case CK_IntegralCast:
12872	return ICK_Integral_Conversion;
12873	case CK_FloatingCast:
12874	return ICK_Floating_Conversion;
12875	case CK_IntegralToFloating:
12876	case CK_FloatingToIntegral:
12877	return ICK_Floating_Integral;
12878	case CK_IntegralComplexCast:
12879	case CK_FloatingComplexCast:
12880	case CK_FloatingComplexToIntegralComplex:
12881	case CK_IntegralComplexToFloatingComplex:
12882	return ICK_Complex_Conversion;
12883	case CK_FloatingComplexToReal:
12884	case CK_FloatingRealToComplex:
12885	case CK_IntegralComplexToReal:
12886	case CK_IntegralRealToComplex:
12887	return ICK_Complex_Real;
12888	}
12889	}
12890
12891	static bool checkThreeWayNarrowingConversion(Sema &S, QualType ToType, Expr *E,
12892	QualType FromType,
12893	SourceLocation Loc) {
12894	// Check for a narrowing implicit conversion.
12895	StandardConversionSequence SCS;
12896	SCS.setAsIdentityConversion();
12897	SCS.setToType(Idx: 0, T: FromType);
12898	SCS.setToType(Idx: 1, T: ToType);
12899	if (const auto *ICE = dyn_cast<ImplicitCastExpr>(Val: E))
12900	SCS.Second = castKindToImplicitConversionKind(ICE->getCastKind());
12901
12902	APValue PreNarrowingValue;
12903	QualType PreNarrowingType;
12904	switch (SCS.getNarrowingKind(Context&: S.Context, Converted: E, ConstantValue&: PreNarrowingValue,
12905	ConstantType&: PreNarrowingType,
12906	/*IgnoreFloatToIntegralConversion*/ true)) {
12907	case NK_Dependent_Narrowing:
12908	// Implicit conversion to a narrower type, but the expression is
12909	// value-dependent so we can't tell whether it's actually narrowing.
12910	case NK_Not_Narrowing:
12911	return false;
12912
12913	case NK_Constant_Narrowing:
12914	// Implicit conversion to a narrower type, and the value is not a constant
12915	// expression.
12916	S.Diag(E->getBeginLoc(), diag::err_spaceship_argument_narrowing)
12917	<< /*Constant*/ 1
12918	<< PreNarrowingValue.getAsString(S.Context, PreNarrowingType) << ToType;
12919	return true;
12920
12921	case NK_Variable_Narrowing:
12922	// Implicit conversion to a narrower type, and the value is not a constant
12923	// expression.
12924	case NK_Type_Narrowing:
12925	S.Diag(E->getBeginLoc(), diag::err_spaceship_argument_narrowing)
12926	<< /*Constant*/ 0 << FromType << ToType;
12927	// TODO: It's not a constant expression, but what if the user intended it
12928	// to be? Can we produce notes to help them figure out why it isn't?
12929	return true;
12930	}
12931	llvm_unreachable("unhandled case in switch");
12932	}
12933
12934	static QualType checkArithmeticOrEnumeralThreeWayCompare(Sema &S,
12935	ExprResult &LHS,
12936	ExprResult &RHS,
12937	SourceLocation Loc) {
12938	QualType LHSType = LHS.get()->getType();
12939	QualType RHSType = RHS.get()->getType();
12940	// Dig out the original argument type and expression before implicit casts
12941	// were applied. These are the types/expressions we need to check the
12942	// [expr.spaceship] requirements against.
12943	ExprResult LHSStripped = LHS.get()->IgnoreParenImpCasts();
12944	ExprResult RHSStripped = RHS.get()->IgnoreParenImpCasts();
12945	QualType LHSStrippedType = LHSStripped.get()->getType();
12946	QualType RHSStrippedType = RHSStripped.get()->getType();
12947
12948	// C++2a [expr.spaceship]p3: If one of the operands is of type bool and the
12949	// other is not, the program is ill-formed.
12950	if (LHSStrippedType->isBooleanType() != RHSStrippedType->isBooleanType()) {
12951	S.InvalidOperands(Loc, LHS&: LHSStripped, RHS&: RHSStripped);
12952	return QualType();
12953	}
12954
12955	// FIXME: Consider combining this with checkEnumArithmeticConversions.
12956	int NumEnumArgs = (int)LHSStrippedType->isEnumeralType() +
12957	RHSStrippedType->isEnumeralType();
12958	if (NumEnumArgs == 1) {
12959	bool LHSIsEnum = LHSStrippedType->isEnumeralType();
12960	QualType OtherTy = LHSIsEnum ? RHSStrippedType : LHSStrippedType;
12961	if (OtherTy->hasFloatingRepresentation()) {
12962	S.InvalidOperands(Loc, LHS&: LHSStripped, RHS&: RHSStripped);
12963	return QualType();
12964	}
12965	}
12966	if (NumEnumArgs == 2) {
12967	// C++2a [expr.spaceship]p5: If both operands have the same enumeration
12968	// type E, the operator yields the result of converting the operands
12969	// to the underlying type of E and applying <=> to the converted operands.
12970	if (!S.Context.hasSameUnqualifiedType(T1: LHSStrippedType, T2: RHSStrippedType)) {
12971	S.InvalidOperands(Loc, LHS, RHS);
12972	return QualType();
12973	}
12974	QualType IntType =
12975	LHSStrippedType->castAs<EnumType>()->getDecl()->getIntegerType();
12976	assert(IntType->isArithmeticType());
12977
12978	// We can't use `CK_IntegralCast` when the underlying type is 'bool', so we
12979	// promote the boolean type, and all other promotable integer types, to
12980	// avoid this.
12981	if (S.Context.isPromotableIntegerType(T: IntType))
12982	IntType = S.Context.getPromotedIntegerType(PromotableType: IntType);
12983
12984	LHS = S.ImpCastExprToType(E: LHS.get(), Type: IntType, CK: CK_IntegralCast);
12985	RHS = S.ImpCastExprToType(E: RHS.get(), Type: IntType, CK: CK_IntegralCast);
12986	LHSType = RHSType = IntType;
12987	}
12988
12989	// C++2a [expr.spaceship]p4: If both operands have arithmetic types, the
12990	// usual arithmetic conversions are applied to the operands.
12991	QualType Type =
12992	S.UsualArithmeticConversions(LHS, RHS, Loc, ACK: Sema::ACK_Comparison);
12993	if (LHS.isInvalid() || RHS.isInvalid())
12994	return QualType();
12995	if (Type.isNull())
12996	return S.InvalidOperands(Loc, LHS, RHS);
12997
12998	std::optional<ComparisonCategoryType> CCT =
12999	getComparisonCategoryForBuiltinCmp(T: Type);
13000	if (!CCT)
13001	return S.InvalidOperands(Loc, LHS, RHS);
13002
13003	bool HasNarrowing = checkThreeWayNarrowingConversion(
13004	S, Type, LHS.get(), LHSType, LHS.get()->getBeginLoc());
13005	HasNarrowing |= checkThreeWayNarrowingConversion(S, Type, RHS.get(), RHSType,
13006	RHS.get()->getBeginLoc());
13007	if (HasNarrowing)
13008	return QualType();
13009
13010	assert(!Type.isNull() && "composite type for <=> has not been set");
13011
13012	return S.CheckComparisonCategoryType(
13013	Kind: *CCT, Loc, Usage: Sema::ComparisonCategoryUsage::OperatorInExpression);
13014	}
13015
13016	static QualType checkArithmeticOrEnumeralCompare(Sema &S, ExprResult &LHS,
13017	ExprResult &RHS,
13018	SourceLocation Loc,
13019	BinaryOperatorKind Opc) {
13020	if (Opc == BO_Cmp)
13021	return checkArithmeticOrEnumeralThreeWayCompare(S, LHS, RHS, Loc);
13022
13023	// C99 6.5.8p3 / C99 6.5.9p4
13024	QualType Type =
13025	S.UsualArithmeticConversions(LHS, RHS, Loc, ACK: Sema::ACK_Comparison);
13026	if (LHS.isInvalid() || RHS.isInvalid())
13027	return QualType();
13028	if (Type.isNull())
13029	return S.InvalidOperands(Loc, LHS, RHS);
13030	assert(Type->isArithmeticType() || Type->isEnumeralType());
13031
13032	if (Type->isAnyComplexType() && BinaryOperator::isRelationalOp(Opc))
13033	return S.InvalidOperands(Loc, LHS, RHS);
13034
13035	// Check for comparisons of floating point operands using != and ==.
13036	if (Type->hasFloatingRepresentation())
13037	S.CheckFloatComparison(Loc, LHS: LHS.get(), RHS: RHS.get(), Opcode: Opc);
13038
13039	// The result of comparisons is 'bool' in C++, 'int' in C.
13040	return S.Context.getLogicalOperationType();
13041	}
13042
13043	void Sema::CheckPtrComparisonWithNullChar(ExprResult &E, ExprResult &NullE) {
13044	if (!NullE.get()->getType()->isAnyPointerType())
13045	return;
13046	int NullValue = PP.isMacroDefined(Id: "NULL") ? 0 : 1;
13047	if (!E.get()->getType()->isAnyPointerType() &&
13048	E.get()->isNullPointerConstant(Ctx&: Context,
13049	NPC: Expr::NPC_ValueDependentIsNotNull) ==
13050	Expr::NPCK_ZeroExpression) {
13051	if (const auto *CL = dyn_cast<CharacterLiteral>(Val: E.get())) {
13052	if (CL->getValue() == 0)
13053	Diag(E.get()->getExprLoc(), diag::warn_pointer_compare)
13054	<< NullValue
13055	<< FixItHint::CreateReplacement(E.get()->getExprLoc(),
13056	NullValue ? "NULL" : "(void *)0");
13057	} else if (const auto *CE = dyn_cast<CStyleCastExpr>(Val: E.get())) {
13058	TypeSourceInfo *TI = CE->getTypeInfoAsWritten();
13059	QualType T = Context.getCanonicalType(T: TI->getType()).getUnqualifiedType();
13060	if (T == Context.CharTy)
13061	Diag(E.get()->getExprLoc(), diag::warn_pointer_compare)
13062	<< NullValue
13063	<< FixItHint::CreateReplacement(E.get()->getExprLoc(),
13064	NullValue ? "NULL" : "(void *)0");
13065	}
13066	}
13067	}
13068
13069	// C99 6.5.8, C++ [expr.rel]
13070	QualType Sema::CheckCompareOperands(ExprResult &LHS, ExprResult &RHS,
13071	SourceLocation Loc,
13072	BinaryOperatorKind Opc) {
13073	bool IsRelational = BinaryOperator::isRelationalOp(Opc);
13074	bool IsThreeWay = Opc == BO_Cmp;
13075	bool IsOrdered = IsRelational || IsThreeWay;
13076	auto IsAnyPointerType = [](ExprResult E) {
13077	QualType Ty = E.get()->getType();
13078	return Ty->isPointerType() || Ty->isMemberPointerType();
13079	};
13080
13081	// C++2a [expr.spaceship]p6: If at least one of the operands is of pointer
13082	// type, array-to-pointer, ..., conversions are performed on both operands to
13083	// bring them to their composite type.
13084	// Otherwise, all comparisons expect an rvalue, so convert to rvalue before
13085	// any type-related checks.
13086	if (!IsThreeWay || IsAnyPointerType(LHS) || IsAnyPointerType(RHS)) {
13087	LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
13088	if (LHS.isInvalid())
13089	return QualType();
13090	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
13091	if (RHS.isInvalid())
13092	return QualType();
13093	} else {
13094	LHS = DefaultLvalueConversion(E: LHS.get());
13095	if (LHS.isInvalid())
13096	return QualType();
13097	RHS = DefaultLvalueConversion(E: RHS.get());
13098	if (RHS.isInvalid())
13099	return QualType();
13100	}
13101
13102	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/true);
13103	if (!getLangOpts().CPlusPlus && BinaryOperator::isEqualityOp(Opc)) {
13104	CheckPtrComparisonWithNullChar(E&: LHS, NullE&: RHS);
13105	CheckPtrComparisonWithNullChar(E&: RHS, NullE&: LHS);
13106	}
13107
13108	// Handle vector comparisons separately.
13109	if (LHS.get()->getType()->isVectorType() ||
13110	RHS.get()->getType()->isVectorType())
13111	return CheckVectorCompareOperands(LHS, RHS, Loc, Opc);
13112
13113	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
13114	RHS.get()->getType()->isSveVLSBuiltinType())
13115	return CheckSizelessVectorCompareOperands(LHS, RHS, Loc, Opc);
13116
13117	diagnoseLogicalNotOnLHSofCheck(S&: *this, LHS, RHS, Loc, Opc);
13118	diagnoseTautologicalComparison(S&: *this, Loc, LHS: LHS.get(), RHS: RHS.get(), Opc);
13119
13120	QualType LHSType = LHS.get()->getType();
13121	QualType RHSType = RHS.get()->getType();
13122	if ((LHSType->isArithmeticType() || LHSType->isEnumeralType()) &&
13123	(RHSType->isArithmeticType() || RHSType->isEnumeralType()))
13124	return checkArithmeticOrEnumeralCompare(S&: *this, LHS, RHS, Loc, Opc);
13125
13126	if ((LHSType->isPointerType() &&
13127	LHSType->getPointeeType().isWebAssemblyReferenceType()) ||
13128	(RHSType->isPointerType() &&
13129	RHSType->getPointeeType().isWebAssemblyReferenceType()))
13130	return InvalidOperands(Loc, LHS, RHS);
13131
13132	const Expr::NullPointerConstantKind LHSNullKind =
13133	LHS.get()->isNullPointerConstant(Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNull);
13134	const Expr::NullPointerConstantKind RHSNullKind =
13135	RHS.get()->isNullPointerConstant(Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNull);
13136	bool LHSIsNull = LHSNullKind != Expr::NPCK_NotNull;
13137	bool RHSIsNull = RHSNullKind != Expr::NPCK_NotNull;
13138
13139	auto computeResultTy = [&]() {
13140	if (Opc != BO_Cmp)
13141	return Context.getLogicalOperationType();
13142	assert(getLangOpts().CPlusPlus);
13143	assert(Context.hasSameType(LHS.get()->getType(), RHS.get()->getType()));
13144
13145	QualType CompositeTy = LHS.get()->getType();
13146	assert(!CompositeTy->isReferenceType());
13147
13148	std::optional<ComparisonCategoryType> CCT =
13149	getComparisonCategoryForBuiltinCmp(T: CompositeTy);
13150	if (!CCT)
13151	return InvalidOperands(Loc, LHS, RHS);
13152
13153	if (CompositeTy->isPointerType() && LHSIsNull != RHSIsNull) {
13154	// P0946R0: Comparisons between a null pointer constant and an object
13155	// pointer result in std::strong_equality, which is ill-formed under
13156	// P1959R0.
13157	Diag(Loc, diag::err_typecheck_three_way_comparison_of_pointer_and_zero)
13158	<< (LHSIsNull ? LHS.get()->getSourceRange()
13159	: RHS.get()->getSourceRange());
13160	return QualType();
13161	}
13162
13163	return CheckComparisonCategoryType(
13164	Kind: *CCT, Loc, Usage: ComparisonCategoryUsage::OperatorInExpression);
13165	};
13166
13167	if (!IsOrdered && LHSIsNull != RHSIsNull) {
13168	bool IsEquality = Opc == BO_EQ;
13169	if (RHSIsNull)
13170	DiagnoseAlwaysNonNullPointer(E: LHS.get(), NullType: RHSNullKind, IsEqual: IsEquality,
13171	Range: RHS.get()->getSourceRange());
13172	else
13173	DiagnoseAlwaysNonNullPointer(E: RHS.get(), NullType: LHSNullKind, IsEqual: IsEquality,
13174	Range: LHS.get()->getSourceRange());
13175	}
13176
13177	if (IsOrdered && LHSType->isFunctionPointerType() &&
13178	RHSType->isFunctionPointerType()) {
13179	// Valid unless a relational comparison of function pointers
13180	bool IsError = Opc == BO_Cmp;
13181	auto DiagID =
13182	IsError ? diag::err_typecheck_ordered_comparison_of_function_pointers
13183	: getLangOpts().CPlusPlus
13184	? diag::warn_typecheck_ordered_comparison_of_function_pointers
13185	: diag::ext_typecheck_ordered_comparison_of_function_pointers;
13186	Diag(Loc, DiagID) << LHSType << RHSType << LHS.get()->getSourceRange()
13187	<< RHS.get()->getSourceRange();
13188	if (IsError)
13189	return QualType();
13190	}
13191
13192	if ((LHSType->isIntegerType() && !LHSIsNull) ||
13193	(RHSType->isIntegerType() && !RHSIsNull)) {
13194	// Skip normal pointer conversion checks in this case; we have better
13195	// diagnostics for this below.
13196	} else if (getLangOpts().CPlusPlus) {
13197	// Equality comparison of a function pointer to a void pointer is invalid,
13198	// but we allow it as an extension.
13199	// FIXME: If we really want to allow this, should it be part of composite
13200	// pointer type computation so it works in conditionals too?
13201	if (!IsOrdered &&
13202	((LHSType->isFunctionPointerType() && RHSType->isVoidPointerType()) ||
13203	(RHSType->isFunctionPointerType() && LHSType->isVoidPointerType()))) {
13204	// This is a gcc extension compatibility comparison.
13205	// In a SFINAE context, we treat this as a hard error to maintain
13206	// conformance with the C++ standard.
13207	diagnoseFunctionPointerToVoidComparison(
13208	S&: *this, Loc, LHS, RHS, /*isError*/ IsError: (bool)isSFINAEContext());
13209
13210	if (isSFINAEContext())
13211	return QualType();
13212
13213	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_BitCast);
13214	return computeResultTy();
13215	}
13216
13217	// C++ [expr.eq]p2:
13218	// If at least one operand is a pointer [...] bring them to their
13219	// composite pointer type.
13220	// C++ [expr.spaceship]p6
13221	// If at least one of the operands is of pointer type, [...] bring them
13222	// to their composite pointer type.
13223	// C++ [expr.rel]p2:
13224	// If both operands are pointers, [...] bring them to their composite
13225	// pointer type.
13226	// For <=>, the only valid non-pointer types are arrays and functions, and
13227	// we already decayed those, so this is really the same as the relational
13228	// comparison rule.
13229	if ((int)LHSType->isPointerType() + (int)RHSType->isPointerType() >=
13230	(IsOrdered ? 2 : 1) &&
13231	(!LangOpts.ObjCAutoRefCount || !(LHSType->isObjCObjectPointerType() ||
13232	RHSType->isObjCObjectPointerType()))) {
13233	if (convertPointersToCompositeType(S&: *this, Loc, LHS, RHS))
13234	return QualType();
13235	return computeResultTy();
13236	}
13237	} else if (LHSType->isPointerType() &&
13238	RHSType->isPointerType()) { // C99 6.5.8p2
13239	// All of the following pointer-related warnings are GCC extensions, except
13240	// when handling null pointer constants.
13241	QualType LCanPointeeTy =
13242	LHSType->castAs<PointerType>()->getPointeeType().getCanonicalType();
13243	QualType RCanPointeeTy =
13244	RHSType->castAs<PointerType>()->getPointeeType().getCanonicalType();
13245
13246	// C99 6.5.9p2 and C99 6.5.8p2
13247	if (Context.typesAreCompatible(T1: LCanPointeeTy.getUnqualifiedType(),
13248	T2: RCanPointeeTy.getUnqualifiedType())) {
13249	if (IsRelational) {
13250	// Pointers both need to point to complete or incomplete types
13251	if ((LCanPointeeTy->isIncompleteType() !=
13252	RCanPointeeTy->isIncompleteType()) &&
13253	!getLangOpts().C11) {
13254	Diag(Loc, diag::ext_typecheck_compare_complete_incomplete_pointers)
13255	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange()
13256	<< LHSType << RHSType << LCanPointeeTy->isIncompleteType()
13257	<< RCanPointeeTy->isIncompleteType();
13258	}
13259	}
13260	} else if (!IsRelational &&
13261	(LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) {
13262	// Valid unless comparison between non-null pointer and function pointer
13263	if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType())
13264	&& !LHSIsNull && !RHSIsNull)
13265	diagnoseFunctionPointerToVoidComparison(S&: *this, Loc, LHS, RHS,
13266	/*isError*/IsError: false);
13267	} else {
13268	// Invalid
13269	diagnoseDistinctPointerComparison(S&: *this, Loc, LHS, RHS, /*isError*/IsError: false);
13270	}
13271	if (LCanPointeeTy != RCanPointeeTy) {
13272	// Treat NULL constant as a special case in OpenCL.
13273	if (getLangOpts().OpenCL && !LHSIsNull && !RHSIsNull) {
13274	if (!LCanPointeeTy.isAddressSpaceOverlapping(T: RCanPointeeTy)) {
13275	Diag(Loc,
13276	diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
13277	<< LHSType << RHSType << 0 /* comparison */
13278	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
13279	}
13280	}
13281	LangAS AddrSpaceL = LCanPointeeTy.getAddressSpace();
13282	LangAS AddrSpaceR = RCanPointeeTy.getAddressSpace();
13283	CastKind Kind = AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion
13284	: CK_BitCast;
13285	if (LHSIsNull && !RHSIsNull)
13286	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: Kind);
13287	else
13288	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: Kind);
13289	}
13290	return computeResultTy();
13291	}
13292
13293
13294	// C++ [expr.eq]p4:
13295	// Two operands of type std::nullptr_t or one operand of type
13296	// std::nullptr_t and the other a null pointer constant compare
13297	// equal.
13298	// C23 6.5.9p5:
13299	// If both operands have type nullptr_t or one operand has type nullptr_t
13300	// and the other is a null pointer constant, they compare equal if the
13301	// former is a null pointer.
13302	if (!IsOrdered && LHSIsNull && RHSIsNull) {
13303	if (LHSType->isNullPtrType()) {
13304	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
13305	return computeResultTy();
13306	}
13307	if (RHSType->isNullPtrType()) {
13308	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
13309	return computeResultTy();
13310	}
13311	}
13312
13313	if (!getLangOpts().CPlusPlus && !IsOrdered && (LHSIsNull || RHSIsNull)) {
13314	// C23 6.5.9p6:
13315	// Otherwise, at least one operand is a pointer. If one is a pointer and
13316	// the other is a null pointer constant or has type nullptr_t, they
13317	// compare equal
13318	if (LHSIsNull && RHSType->isPointerType()) {
13319	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
13320	return computeResultTy();
13321	}
13322	if (RHSIsNull && LHSType->isPointerType()) {
13323	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
13324	return computeResultTy();
13325	}
13326	}
13327
13328	// Comparison of Objective-C pointers and block pointers against nullptr_t.
13329	// These aren't covered by the composite pointer type rules.
13330	if (!IsOrdered && RHSType->isNullPtrType() &&
13331	(LHSType->isObjCObjectPointerType() || LHSType->isBlockPointerType())) {
13332	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
13333	return computeResultTy();
13334	}
13335	if (!IsOrdered && LHSType->isNullPtrType() &&
13336	(RHSType->isObjCObjectPointerType() || RHSType->isBlockPointerType())) {
13337	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
13338	return computeResultTy();
13339	}
13340
13341	if (getLangOpts().CPlusPlus) {
13342	if (IsRelational &&
13343	((LHSType->isNullPtrType() && RHSType->isPointerType()) ||
13344	(RHSType->isNullPtrType() && LHSType->isPointerType()))) {
13345	// HACK: Relational comparison of nullptr_t against a pointer type is
13346	// invalid per DR583, but we allow it within std::less<> and friends,
13347	// since otherwise common uses of it break.
13348	// FIXME: Consider removing this hack once LWG fixes std::less<> and
13349	// friends to have std::nullptr_t overload candidates.
13350	DeclContext *DC = CurContext;
13351	if (isa<FunctionDecl>(Val: DC))
13352	DC = DC->getParent();
13353	if (auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(Val: DC)) {
13354	if (CTSD->isInStdNamespace() &&
13355	llvm::StringSwitch<bool>(CTSD->getName())
13356	.Cases(S0: "less", S1: "less_equal", S2: "greater", S3: "greater_equal", Value: true)
13357	.Default(Value: false)) {
13358	if (RHSType->isNullPtrType())
13359	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
13360	else
13361	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
13362	return computeResultTy();
13363	}
13364	}
13365	}
13366
13367	// C++ [expr.eq]p2:
13368	// If at least one operand is a pointer to member, [...] bring them to
13369	// their composite pointer type.
13370	if (!IsOrdered &&
13371	(LHSType->isMemberPointerType() || RHSType->isMemberPointerType())) {
13372	if (convertPointersToCompositeType(S&: *this, Loc, LHS, RHS))
13373	return QualType();
13374	else
13375	return computeResultTy();
13376	}
13377	}
13378
13379	// Handle block pointer types.
13380	if (!IsOrdered && LHSType->isBlockPointerType() &&
13381	RHSType->isBlockPointerType()) {
13382	QualType lpointee = LHSType->castAs<BlockPointerType>()->getPointeeType();
13383	QualType rpointee = RHSType->castAs<BlockPointerType>()->getPointeeType();
13384
13385	if (!LHSIsNull && !RHSIsNull &&
13386	!Context.typesAreCompatible(T1: lpointee, T2: rpointee)) {
13387	Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks)
13388	<< LHSType << RHSType << LHS.get()->getSourceRange()
13389	<< RHS.get()->getSourceRange();
13390	}
13391	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_BitCast);
13392	return computeResultTy();
13393	}
13394
13395	// Allow block pointers to be compared with null pointer constants.
13396	if (!IsOrdered
13397	&& ((LHSType->isBlockPointerType() && RHSType->isPointerType())
13398	|| (LHSType->isPointerType() && RHSType->isBlockPointerType()))) {
13399	if (!LHSIsNull && !RHSIsNull) {
13400	if (!((RHSType->isPointerType() && RHSType->castAs<PointerType>()
13401	->getPointeeType()->isVoidType())
13402	|| (LHSType->isPointerType() && LHSType->castAs<PointerType>()
13403	->getPointeeType()->isVoidType())))
13404	Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks)
13405	<< LHSType << RHSType << LHS.get()->getSourceRange()
13406	<< RHS.get()->getSourceRange();
13407	}
13408	if (LHSIsNull && !RHSIsNull)
13409	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType,
13410	CK: RHSType->isPointerType() ? CK_BitCast
13411	: CK_AnyPointerToBlockPointerCast);
13412	else
13413	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType,
13414	CK: LHSType->isPointerType() ? CK_BitCast
13415	: CK_AnyPointerToBlockPointerCast);
13416	return computeResultTy();
13417	}
13418
13419	if (LHSType->isObjCObjectPointerType() ||
13420	RHSType->isObjCObjectPointerType()) {
13421	const PointerType *LPT = LHSType->getAs<PointerType>();
13422	const PointerType *RPT = RHSType->getAs<PointerType>();
13423	if (LPT || RPT) {
13424	bool LPtrToVoid = LPT ? LPT->getPointeeType()->isVoidType() : false;
13425	bool RPtrToVoid = RPT ? RPT->getPointeeType()->isVoidType() : false;
13426
13427	if (!LPtrToVoid && !RPtrToVoid &&
13428	!Context.typesAreCompatible(T1: LHSType, T2: RHSType)) {
13429	diagnoseDistinctPointerComparison(S&: *this, Loc, LHS, RHS,
13430	/*isError*/IsError: false);
13431	}
13432	// FIXME: If LPtrToVoid, we should presumably convert the LHS rather than
13433	// the RHS, but we have test coverage for this behavior.
13434	// FIXME: Consider using convertPointersToCompositeType in C++.
13435	if (LHSIsNull && !RHSIsNull) {
13436	Expr *E = LHS.get();
13437	if (getLangOpts().ObjCAutoRefCount)
13438	CheckObjCConversion(castRange: SourceRange(), castType: RHSType, op&: E,
13439	CCK: CCK_ImplicitConversion);
13440	LHS = ImpCastExprToType(E, Type: RHSType,
13441	CK: RPT ? CK_BitCast :CK_CPointerToObjCPointerCast);
13442	}
13443	else {
13444	Expr *E = RHS.get();
13445	if (getLangOpts().ObjCAutoRefCount)
13446	CheckObjCConversion(castRange: SourceRange(), castType: LHSType, op&: E, CCK: CCK_ImplicitConversion,
13447	/*Diagnose=*/true,
13448	/*DiagnoseCFAudited=*/false, Opc);
13449	RHS = ImpCastExprToType(E, Type: LHSType,
13450	CK: LPT ? CK_BitCast :CK_CPointerToObjCPointerCast);
13451	}
13452	return computeResultTy();
13453	}
13454	if (LHSType->isObjCObjectPointerType() &&
13455	RHSType->isObjCObjectPointerType()) {
13456	if (!Context.areComparableObjCPointerTypes(LHS: LHSType, RHS: RHSType))
13457	diagnoseDistinctPointerComparison(S&: *this, Loc, LHS, RHS,
13458	/*isError*/IsError: false);
13459	if (isObjCObjectLiteral(E&: LHS) || isObjCObjectLiteral(E&: RHS))
13460	diagnoseObjCLiteralComparison(S&: *this, Loc, LHS, RHS, Opc);
13461
13462	if (LHSIsNull && !RHSIsNull)
13463	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_BitCast);
13464	else
13465	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_BitCast);
13466	return computeResultTy();
13467	}
13468
13469	if (!IsOrdered && LHSType->isBlockPointerType() &&
13470	RHSType->isBlockCompatibleObjCPointerType(ctx&: Context)) {
13471	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType,
13472	CK: CK_BlockPointerToObjCPointerCast);
13473	return computeResultTy();
13474	} else if (!IsOrdered &&
13475	LHSType->isBlockCompatibleObjCPointerType(ctx&: Context) &&
13476	RHSType->isBlockPointerType()) {
13477	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType,
13478	CK: CK_BlockPointerToObjCPointerCast);
13479	return computeResultTy();
13480	}
13481	}
13482	if ((LHSType->isAnyPointerType() && RHSType->isIntegerType()) ||
13483	(LHSType->isIntegerType() && RHSType->isAnyPointerType())) {
13484	unsigned DiagID = 0;
13485	bool isError = false;
13486	if (LangOpts.DebuggerSupport) {
13487	// Under a debugger, allow the comparison of pointers to integers,
13488	// since users tend to want to compare addresses.
13489	} else if ((LHSIsNull && LHSType->isIntegerType()) ||
13490	(RHSIsNull && RHSType->isIntegerType())) {
13491	if (IsOrdered) {
13492	isError = getLangOpts().CPlusPlus;
13493	DiagID =
13494	isError ? diag::err_typecheck_ordered_comparison_of_pointer_and_zero
13495	: diag::ext_typecheck_ordered_comparison_of_pointer_and_zero;
13496	}
13497	} else if (getLangOpts().CPlusPlus) {
13498	DiagID = diag::err_typecheck_comparison_of_pointer_integer;
13499	isError = true;
13500	} else if (IsOrdered)
13501	DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer;
13502	else
13503	DiagID = diag::ext_typecheck_comparison_of_pointer_integer;
13504
13505	if (DiagID) {
13506	Diag(Loc, DiagID)
13507	<< LHSType << RHSType << LHS.get()->getSourceRange()
13508	<< RHS.get()->getSourceRange();
13509	if (isError)
13510	return QualType();
13511	}
13512
13513	if (LHSType->isIntegerType())
13514	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType,
13515	CK: LHSIsNull ? CK_NullToPointer : CK_IntegralToPointer);
13516	else
13517	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType,
13518	CK: RHSIsNull ? CK_NullToPointer : CK_IntegralToPointer);
13519	return computeResultTy();
13520	}
13521
13522	// Handle block pointers.
13523	if (!IsOrdered && RHSIsNull
13524	&& LHSType->isBlockPointerType() && RHSType->isIntegerType()) {
13525	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
13526	return computeResultTy();
13527	}
13528	if (!IsOrdered && LHSIsNull
13529	&& LHSType->isIntegerType() && RHSType->isBlockPointerType()) {
13530	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
13531	return computeResultTy();
13532	}
13533
13534	if (getLangOpts().getOpenCLCompatibleVersion() >= 200) {
13535	if (LHSType->isClkEventT() && RHSType->isClkEventT()) {
13536	return computeResultTy();
13537	}
13538
13539	if (LHSType->isQueueT() && RHSType->isQueueT()) {
13540	return computeResultTy();
13541	}
13542
13543	if (LHSIsNull && RHSType->isQueueT()) {
13544	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
13545	return computeResultTy();
13546	}
13547
13548	if (LHSType->isQueueT() && RHSIsNull) {
13549	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
13550	return computeResultTy();
13551	}
13552	}
13553
13554	return InvalidOperands(Loc, LHS, RHS);
13555	}
13556
13557	// Return a signed ext_vector_type that is of identical size and number of
13558	// elements. For floating point vectors, return an integer type of identical
13559	// size and number of elements. In the non ext_vector_type case, search from
13560	// the largest type to the smallest type to avoid cases where long long == long,
13561	// where long gets picked over long long.
13562	QualType Sema::GetSignedVectorType(QualType V) {
13563	const VectorType *VTy = V->castAs<VectorType>();
13564	unsigned TypeSize = Context.getTypeSize(T: VTy->getElementType());
13565
13566	if (isa<ExtVectorType>(Val: VTy)) {
13567	if (VTy->isExtVectorBoolType())
13568	return Context.getExtVectorType(VectorType: Context.BoolTy, NumElts: VTy->getNumElements());
13569	if (TypeSize == Context.getTypeSize(Context.CharTy))
13570	return Context.getExtVectorType(VectorType: Context.CharTy, NumElts: VTy->getNumElements());
13571	if (TypeSize == Context.getTypeSize(Context.ShortTy))
13572	return Context.getExtVectorType(VectorType: Context.ShortTy, NumElts: VTy->getNumElements());
13573	if (TypeSize == Context.getTypeSize(Context.IntTy))
13574	return Context.getExtVectorType(VectorType: Context.IntTy, NumElts: VTy->getNumElements());
13575	if (TypeSize == Context.getTypeSize(Context.Int128Ty))
13576	return Context.getExtVectorType(VectorType: Context.Int128Ty, NumElts: VTy->getNumElements());
13577	if (TypeSize == Context.getTypeSize(Context.LongTy))
13578	return Context.getExtVectorType(VectorType: Context.LongTy, NumElts: VTy->getNumElements());
13579	assert(TypeSize == Context.getTypeSize(Context.LongLongTy) &&
13580	"Unhandled vector element size in vector compare");
13581	return Context.getExtVectorType(VectorType: Context.LongLongTy, NumElts: VTy->getNumElements());
13582	}
13583
13584	if (TypeSize == Context.getTypeSize(Context.Int128Ty))
13585	return Context.getVectorType(VectorType: Context.Int128Ty, NumElts: VTy->getNumElements(),
13586	VecKind: VectorKind::Generic);
13587	if (TypeSize == Context.getTypeSize(Context.LongLongTy))
13588	return Context.getVectorType(VectorType: Context.LongLongTy, NumElts: VTy->getNumElements(),
13589	VecKind: VectorKind::Generic);
13590	if (TypeSize == Context.getTypeSize(Context.LongTy))
13591	return Context.getVectorType(VectorType: Context.LongTy, NumElts: VTy->getNumElements(),
13592	VecKind: VectorKind::Generic);
13593	if (TypeSize == Context.getTypeSize(Context.IntTy))
13594	return Context.getVectorType(VectorType: Context.IntTy, NumElts: VTy->getNumElements(),
13595	VecKind: VectorKind::Generic);
13596	if (TypeSize == Context.getTypeSize(Context.ShortTy))
13597	return Context.getVectorType(VectorType: Context.ShortTy, NumElts: VTy->getNumElements(),
13598	VecKind: VectorKind::Generic);
13599	assert(TypeSize == Context.getTypeSize(Context.CharTy) &&
13600	"Unhandled vector element size in vector compare");
13601	return Context.getVectorType(VectorType: Context.CharTy, NumElts: VTy->getNumElements(),
13602	VecKind: VectorKind::Generic);
13603	}
13604
13605	QualType Sema::GetSignedSizelessVectorType(QualType V) {
13606	const BuiltinType *VTy = V->castAs<BuiltinType>();
13607	assert(VTy->isSizelessBuiltinType() && "expected sizeless type");
13608
13609	const QualType ETy = V->getSveEltType(Ctx: Context);
13610	const auto TypeSize = Context.getTypeSize(T: ETy);
13611
13612	const QualType IntTy = Context.getIntTypeForBitwidth(DestWidth: TypeSize, Signed: true);
13613	const llvm::ElementCount VecSize = Context.getBuiltinVectorTypeInfo(VecTy: VTy).EC;
13614	return Context.getScalableVectorType(EltTy: IntTy, NumElts: VecSize.getKnownMinValue());
13615	}
13616
13617	/// CheckVectorCompareOperands - vector comparisons are a clang extension that
13618	/// operates on extended vector types. Instead of producing an IntTy result,
13619	/// like a scalar comparison, a vector comparison produces a vector of integer
13620	/// types.
13621	QualType Sema::CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS,
13622	SourceLocation Loc,
13623	BinaryOperatorKind Opc) {
13624	if (Opc == BO_Cmp) {
13625	Diag(Loc, diag::err_three_way_vector_comparison);
13626	return QualType();
13627	}
13628
13629	// Check to make sure we're operating on vectors of the same type and width,
13630	// Allowing one side to be a scalar of element type.
13631	QualType vType =
13632	CheckVectorOperands(LHS, RHS, Loc, /*isCompAssign*/ IsCompAssign: false,
13633	/*AllowBothBool*/ true,
13634	/*AllowBoolConversions*/ getLangOpts().ZVector,
13635	/*AllowBooleanOperation*/ AllowBoolOperation: true,
13636	/*ReportInvalid*/ true);
13637	if (vType.isNull())
13638	return vType;
13639
13640	QualType LHSType = LHS.get()->getType();
13641
13642	// Determine the return type of a vector compare. By default clang will return
13643	// a scalar for all vector compares except vector bool and vector pixel.
13644	// With the gcc compiler we will always return a vector type and with the xl
13645	// compiler we will always return a scalar type. This switch allows choosing
13646	// which behavior is prefered.
13647	if (getLangOpts().AltiVec) {
13648	switch (getLangOpts().getAltivecSrcCompat()) {
13649	case LangOptions::AltivecSrcCompatKind::Mixed:
13650	// If AltiVec, the comparison results in a numeric type, i.e.
13651	// bool for C++, int for C
13652	if (vType->castAs<VectorType>()->getVectorKind() ==
13653	VectorKind::AltiVecVector)
13654	return Context.getLogicalOperationType();
13655	else
13656	Diag(Loc, diag::warn_deprecated_altivec_src_compat);
13657	break;
13658	case LangOptions::AltivecSrcCompatKind::GCC:
13659	// For GCC we always return the vector type.
13660	break;
13661	case LangOptions::AltivecSrcCompatKind::XL:
13662	return Context.getLogicalOperationType();
13663	break;
13664	}
13665	}
13666
13667	// For non-floating point types, check for self-comparisons of the form
13668	// x == x, x != x, x < x, etc. These always evaluate to a constant, and
13669	// often indicate logic errors in the program.
13670	diagnoseTautologicalComparison(S&: *this, Loc, LHS: LHS.get(), RHS: RHS.get(), Opc);
13671
13672	// Check for comparisons of floating point operands using != and ==.
13673	if (LHSType->hasFloatingRepresentation()) {
13674	assert(RHS.get()->getType()->hasFloatingRepresentation());
13675	CheckFloatComparison(Loc, LHS: LHS.get(), RHS: RHS.get(), Opcode: Opc);
13676	}
13677
13678	// Return a signed type for the vector.
13679	return GetSignedVectorType(V: vType);
13680	}
13681
13682	QualType Sema::CheckSizelessVectorCompareOperands(ExprResult &LHS,
13683	ExprResult &RHS,
13684	SourceLocation Loc,
13685	BinaryOperatorKind Opc) {
13686	if (Opc == BO_Cmp) {
13687	Diag(Loc, diag::err_three_way_vector_comparison);
13688	return QualType();
13689	}
13690
13691	// Check to make sure we're operating on vectors of the same type and width,
13692	// Allowing one side to be a scalar of element type.
13693	QualType vType = CheckSizelessVectorOperands(
13694	LHS, RHS, Loc, /*isCompAssign*/ IsCompAssign: false, OperationKind: ACK_Comparison);
13695
13696	if (vType.isNull())
13697	return vType;
13698
13699	QualType LHSType = LHS.get()->getType();
13700
13701	// For non-floating point types, check for self-comparisons of the form
13702	// x == x, x != x, x < x, etc. These always evaluate to a constant, and
13703	// often indicate logic errors in the program.
13704	diagnoseTautologicalComparison(S&: *this, Loc, LHS: LHS.get(), RHS: RHS.get(), Opc);
13705
13706	// Check for comparisons of floating point operands using != and ==.
13707	if (LHSType->hasFloatingRepresentation()) {
13708	assert(RHS.get()->getType()->hasFloatingRepresentation());
13709	CheckFloatComparison(Loc, LHS: LHS.get(), RHS: RHS.get(), Opcode: Opc);
13710	}
13711
13712	const BuiltinType *LHSBuiltinTy = LHSType->getAs<BuiltinType>();
13713	const BuiltinType *RHSBuiltinTy = RHS.get()->getType()->getAs<BuiltinType>();
13714
13715	if (LHSBuiltinTy && RHSBuiltinTy && LHSBuiltinTy->isSVEBool() &&
13716	RHSBuiltinTy->isSVEBool())
13717	return LHSType;
13718
13719	// Return a signed type for the vector.
13720	return GetSignedSizelessVectorType(V: vType);
13721	}
13722
13723	static void diagnoseXorMisusedAsPow(Sema &S, const ExprResult &XorLHS,
13724	const ExprResult &XorRHS,
13725	const SourceLocation Loc) {
13726	// Do not diagnose macros.
13727	if (Loc.isMacroID())
13728	return;
13729
13730	// Do not diagnose if both LHS and RHS are macros.
13731	if (XorLHS.get()->getExprLoc().isMacroID() &&
13732	XorRHS.get()->getExprLoc().isMacroID())
13733	return;
13734
13735	bool Negative = false;
13736	bool ExplicitPlus = false;
13737	const auto *LHSInt = dyn_cast<IntegerLiteral>(Val: XorLHS.get());
13738	const auto *RHSInt = dyn_cast<IntegerLiteral>(Val: XorRHS.get());
13739
13740	if (!LHSInt)
13741	return;
13742	if (!RHSInt) {
13743	// Check negative literals.
13744	if (const auto *UO = dyn_cast<UnaryOperator>(Val: XorRHS.get())) {
13745	UnaryOperatorKind Opc = UO->getOpcode();
13746	if (Opc != UO_Minus && Opc != UO_Plus)
13747	return;
13748	RHSInt = dyn_cast<IntegerLiteral>(Val: UO->getSubExpr());
13749	if (!RHSInt)
13750	return;
13751	Negative = (Opc == UO_Minus);
13752	ExplicitPlus = !Negative;
13753	} else {
13754	return;
13755	}
13756	}
13757
13758	const llvm::APInt &LeftSideValue = LHSInt->getValue();
13759	llvm::APInt RightSideValue = RHSInt->getValue();
13760	if (LeftSideValue != 2 && LeftSideValue != 10)
13761	return;
13762
13763	if (LeftSideValue.getBitWidth() != RightSideValue.getBitWidth())
13764	return;
13765
13766	CharSourceRange ExprRange = CharSourceRange::getCharRange(
13767	B: LHSInt->getBeginLoc(), E: S.getLocForEndOfToken(Loc: RHSInt->getLocation()));
13768	llvm::StringRef ExprStr =
13769	Lexer::getSourceText(Range: ExprRange, SM: S.getSourceManager(), LangOpts: S.getLangOpts());
13770
13771	CharSourceRange XorRange =
13772	CharSourceRange::getCharRange(B: Loc, E: S.getLocForEndOfToken(Loc));
13773	llvm::StringRef XorStr =
13774	Lexer::getSourceText(Range: XorRange, SM: S.getSourceManager(), LangOpts: S.getLangOpts());
13775	// Do not diagnose if xor keyword/macro is used.
13776	if (XorStr == "xor")
13777	return;
13778
13779	std::string LHSStr = std::string(Lexer::getSourceText(
13780	Range: CharSourceRange::getTokenRange(LHSInt->getSourceRange()),
13781	SM: S.getSourceManager(), LangOpts: S.getLangOpts()));
13782	std::string RHSStr = std::string(Lexer::getSourceText(
13783	Range: CharSourceRange::getTokenRange(RHSInt->getSourceRange()),
13784	SM: S.getSourceManager(), LangOpts: S.getLangOpts()));
13785
13786	if (Negative) {
13787	RightSideValue = -RightSideValue;
13788	RHSStr = "-" + RHSStr;
13789	} else if (ExplicitPlus) {
13790	RHSStr = "+" + RHSStr;
13791	}
13792
13793	StringRef LHSStrRef = LHSStr;
13794	StringRef RHSStrRef = RHSStr;
13795	// Do not diagnose literals with digit separators, binary, hexadecimal, octal
13796	// literals.
13797	if (LHSStrRef.starts_with(Prefix: "0b") || LHSStrRef.starts_with(Prefix: "0B") ||
13798	RHSStrRef.starts_with(Prefix: "0b") || RHSStrRef.starts_with(Prefix: "0B") ||
13799	LHSStrRef.starts_with(Prefix: "0x") || LHSStrRef.starts_with(Prefix: "0X") ||
13800	RHSStrRef.starts_with(Prefix: "0x") || RHSStrRef.starts_with(Prefix: "0X") ||
13801	(LHSStrRef.size() > 1 && LHSStrRef.starts_with(Prefix: "0")) ||
13802	(RHSStrRef.size() > 1 && RHSStrRef.starts_with(Prefix: "0")) ||
13803	LHSStrRef.contains(C: '\'') || RHSStrRef.contains(C: '\''))
13804	return;
13805
13806	bool SuggestXor =
13807	S.getLangOpts().CPlusPlus || S.getPreprocessor().isMacroDefined(Id: "xor");
13808	const llvm::APInt XorValue = LeftSideValue ^ RightSideValue;
13809	int64_t RightSideIntValue = RightSideValue.getSExtValue();
13810	if (LeftSideValue == 2 && RightSideIntValue >= 0) {
13811	std::string SuggestedExpr = "1 << " + RHSStr;
13812	bool Overflow = false;
13813	llvm::APInt One = (LeftSideValue - 1);
13814	llvm::APInt PowValue = One.sshl_ov(Amt: RightSideValue, Overflow);
13815	if (Overflow) {
13816	if (RightSideIntValue < 64)
13817	S.Diag(Loc, diag::warn_xor_used_as_pow_base)
13818	<< ExprStr << toString(XorValue, 10, true) << ("1LL << " + RHSStr)
13819	<< FixItHint::CreateReplacement(ExprRange, "1LL << " + RHSStr);
13820	else if (RightSideIntValue == 64)
13821	S.Diag(Loc, diag::warn_xor_used_as_pow)
13822	<< ExprStr << toString(XorValue, 10, true);
13823	else
13824	return;
13825	} else {
13826	S.Diag(Loc, diag::warn_xor_used_as_pow_base_extra)
13827	<< ExprStr << toString(XorValue, 10, true) << SuggestedExpr
13828	<< toString(PowValue, 10, true)
13829	<< FixItHint::CreateReplacement(
13830	ExprRange, (RightSideIntValue == 0) ? "1" : SuggestedExpr);
13831	}
13832
13833	S.Diag(Loc, diag::note_xor_used_as_pow_silence)
13834	<< ("0x2 ^ " + RHSStr) << SuggestXor;
13835	} else if (LeftSideValue == 10) {
13836	std::string SuggestedValue = "1e" + std::to_string(val: RightSideIntValue);
13837	S.Diag(Loc, diag::warn_xor_used_as_pow_base)
13838	<< ExprStr << toString(XorValue, 10, true) << SuggestedValue
13839	<< FixItHint::CreateReplacement(ExprRange, SuggestedValue);
13840	S.Diag(Loc, diag::note_xor_used_as_pow_silence)
13841	<< ("0xA ^ " + RHSStr) << SuggestXor;
13842	}
13843	}
13844
13845	QualType Sema::CheckVectorLogicalOperands(ExprResult &LHS, ExprResult &RHS,
13846	SourceLocation Loc) {
13847	// Ensure that either both operands are of the same vector type, or
13848	// one operand is of a vector type and the other is of its element type.
13849	QualType vType = CheckVectorOperands(LHS, RHS, Loc, IsCompAssign: false,
13850	/*AllowBothBool*/ true,
13851	/*AllowBoolConversions*/ false,
13852	/*AllowBooleanOperation*/ AllowBoolOperation: false,
13853	/*ReportInvalid*/ false);
13854	if (vType.isNull())
13855	return InvalidOperands(Loc, LHS, RHS);
13856	if (getLangOpts().OpenCL &&
13857	getLangOpts().getOpenCLCompatibleVersion() < 120 &&
13858	vType->hasFloatingRepresentation())
13859	return InvalidOperands(Loc, LHS, RHS);
13860	// FIXME: The check for C++ here is for GCC compatibility. GCC rejects the
13861	// usage of the logical operators && and || with vectors in C. This
13862	// check could be notionally dropped.
13863	if (!getLangOpts().CPlusPlus &&
13864	!(isa<ExtVectorType>(Val: vType->getAs<VectorType>())))
13865	return InvalidLogicalVectorOperands(Loc, LHS, RHS);
13866
13867	return GetSignedVectorType(V: LHS.get()->getType());
13868	}
13869
13870	QualType Sema::CheckMatrixElementwiseOperands(ExprResult &LHS, ExprResult &RHS,
13871	SourceLocation Loc,
13872	bool IsCompAssign) {
13873	if (!IsCompAssign) {
13874	LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
13875	if (LHS.isInvalid())
13876	return QualType();
13877	}
13878	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
13879	if (RHS.isInvalid())
13880	return QualType();
13881
13882	// For conversion purposes, we ignore any qualifiers.
13883	// For example, "const float" and "float" are equivalent.
13884	QualType LHSType = LHS.get()->getType().getUnqualifiedType();
13885	QualType RHSType = RHS.get()->getType().getUnqualifiedType();
13886
13887	const MatrixType *LHSMatType = LHSType->getAs<MatrixType>();
13888	const MatrixType *RHSMatType = RHSType->getAs<MatrixType>();
13889	assert((LHSMatType || RHSMatType) && "At least one operand must be a matrix");
13890
13891	if (Context.hasSameType(T1: LHSType, T2: RHSType))
13892	return Context.getCommonSugaredType(X: LHSType, Y: RHSType);
13893
13894	// Type conversion may change LHS/RHS. Keep copies to the original results, in
13895	// case we have to return InvalidOperands.
13896	ExprResult OriginalLHS = LHS;
13897	ExprResult OriginalRHS = RHS;
13898	if (LHSMatType && !RHSMatType) {
13899	RHS = tryConvertExprToType(E: RHS.get(), Ty: LHSMatType->getElementType());
13900	if (!RHS.isInvalid())
13901	return LHSType;
13902
13903	return InvalidOperands(Loc, LHS&: OriginalLHS, RHS&: OriginalRHS);
13904	}
13905
13906	if (!LHSMatType && RHSMatType) {
13907	LHS = tryConvertExprToType(E: LHS.get(), Ty: RHSMatType->getElementType());
13908	if (!LHS.isInvalid())
13909	return RHSType;
13910	return InvalidOperands(Loc, LHS&: OriginalLHS, RHS&: OriginalRHS);
13911	}
13912
13913	return InvalidOperands(Loc, LHS, RHS);
13914	}
13915
13916	QualType Sema::CheckMatrixMultiplyOperands(ExprResult &LHS, ExprResult &RHS,
13917	SourceLocation Loc,
13918	bool IsCompAssign) {
13919	if (!IsCompAssign) {
13920	LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
13921	if (LHS.isInvalid())
13922	return QualType();
13923	}
13924	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
13925	if (RHS.isInvalid())
13926	return QualType();
13927
13928	auto *LHSMatType = LHS.get()->getType()->getAs<ConstantMatrixType>();
13929	auto *RHSMatType = RHS.get()->getType()->getAs<ConstantMatrixType>();
13930	assert((LHSMatType || RHSMatType) && "At least one operand must be a matrix");
13931
13932	if (LHSMatType && RHSMatType) {
13933	if (LHSMatType->getNumColumns() != RHSMatType->getNumRows())
13934	return InvalidOperands(Loc, LHS, RHS);
13935
13936	if (Context.hasSameType(LHSMatType, RHSMatType))
13937	return Context.getCommonSugaredType(
13938	X: LHS.get()->getType().getUnqualifiedType(),
13939	Y: RHS.get()->getType().getUnqualifiedType());
13940
13941	QualType LHSELTy = LHSMatType->getElementType(),
13942	RHSELTy = RHSMatType->getElementType();
13943	if (!Context.hasSameType(T1: LHSELTy, T2: RHSELTy))
13944	return InvalidOperands(Loc, LHS, RHS);
13945
13946	return Context.getConstantMatrixType(
13947	ElementType: Context.getCommonSugaredType(X: LHSELTy, Y: RHSELTy),
13948	NumRows: LHSMatType->getNumRows(), NumColumns: RHSMatType->getNumColumns());
13949	}
13950	return CheckMatrixElementwiseOperands(LHS, RHS, Loc, IsCompAssign);
13951	}
13952
13953	static bool isLegalBoolVectorBinaryOp(BinaryOperatorKind Opc) {
13954	switch (Opc) {
13955	default:
13956	return false;
13957	case BO_And:
13958	case BO_AndAssign:
13959	case BO_Or:
13960	case BO_OrAssign:
13961	case BO_Xor:
13962	case BO_XorAssign:
13963	return true;
13964	}
13965	}
13966
13967	inline QualType Sema::CheckBitwiseOperands(ExprResult &LHS, ExprResult &RHS,
13968	SourceLocation Loc,
13969	BinaryOperatorKind Opc) {
13970	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
13971
13972	bool IsCompAssign =
13973	Opc == BO_AndAssign || Opc == BO_OrAssign || Opc == BO_XorAssign;
13974
13975	bool LegalBoolVecOperator = isLegalBoolVectorBinaryOp(Opc);
13976
13977	if (LHS.get()->getType()->isVectorType() ||
13978	RHS.get()->getType()->isVectorType()) {
13979	if (LHS.get()->getType()->hasIntegerRepresentation() &&
13980	RHS.get()->getType()->hasIntegerRepresentation())
13981	return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
13982	/*AllowBothBool*/ true,
13983	/*AllowBoolConversions*/ getLangOpts().ZVector,
13984	/*AllowBooleanOperation*/ AllowBoolOperation: LegalBoolVecOperator,
13985	/*ReportInvalid*/ true);
13986	return InvalidOperands(Loc, LHS, RHS);
13987	}
13988
13989	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
13990	RHS.get()->getType()->isSveVLSBuiltinType()) {
13991	if (LHS.get()->getType()->hasIntegerRepresentation() &&
13992	RHS.get()->getType()->hasIntegerRepresentation())
13993	return CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign,
13994	OperationKind: ACK_BitwiseOp);
13995	return InvalidOperands(Loc, LHS, RHS);
13996	}
13997
13998	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
13999	RHS.get()->getType()->isSveVLSBuiltinType()) {
14000	if (LHS.get()->getType()->hasIntegerRepresentation() &&
14001	RHS.get()->getType()->hasIntegerRepresentation())
14002	return CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign,
14003	OperationKind: ACK_BitwiseOp);
14004	return InvalidOperands(Loc, LHS, RHS);
14005	}
14006
14007	if (Opc == BO_And)
14008	diagnoseLogicalNotOnLHSofCheck(S&: *this, LHS, RHS, Loc, Opc);
14009
14010	if (LHS.get()->getType()->hasFloatingRepresentation() ||
14011	RHS.get()->getType()->hasFloatingRepresentation())
14012	return InvalidOperands(Loc, LHS, RHS);
14013
14014	ExprResult LHSResult = LHS, RHSResult = RHS;
14015	QualType compType = UsualArithmeticConversions(
14016	LHS&: LHSResult, RHS&: RHSResult, Loc, ACK: IsCompAssign ? ACK_CompAssign : ACK_BitwiseOp);
14017	if (LHSResult.isInvalid() || RHSResult.isInvalid())
14018	return QualType();
14019	LHS = LHSResult.get();
14020	RHS = RHSResult.get();
14021
14022	if (Opc == BO_Xor)
14023	diagnoseXorMisusedAsPow(S&: *this, XorLHS: LHS, XorRHS: RHS, Loc);
14024
14025	if (!compType.isNull() && compType->isIntegralOrUnscopedEnumerationType())
14026	return compType;
14027	return InvalidOperands(Loc, LHS, RHS);
14028	}
14029
14030	// C99 6.5.[13,14]
14031	inline QualType Sema::CheckLogicalOperands(ExprResult &LHS, ExprResult &RHS,
14032	SourceLocation Loc,
14033	BinaryOperatorKind Opc) {
14034	// Check vector operands differently.
14035	if (LHS.get()->getType()->isVectorType() ||
14036	RHS.get()->getType()->isVectorType())
14037	return CheckVectorLogicalOperands(LHS, RHS, Loc);
14038
14039	bool EnumConstantInBoolContext = false;
14040	for (const ExprResult &HS : {LHS, RHS}) {
14041	if (const auto *DREHS = dyn_cast<DeclRefExpr>(Val: HS.get())) {
14042	const auto *ECDHS = dyn_cast<EnumConstantDecl>(Val: DREHS->getDecl());
14043	if (ECDHS && ECDHS->getInitVal() != 0 && ECDHS->getInitVal() != 1)
14044	EnumConstantInBoolContext = true;
14045	}
14046	}
14047
14048	if (EnumConstantInBoolContext)
14049	Diag(Loc, diag::warn_enum_constant_in_bool_context);
14050
14051	// WebAssembly tables can't be used with logical operators.
14052	QualType LHSTy = LHS.get()->getType();
14053	QualType RHSTy = RHS.get()->getType();
14054	const auto *LHSATy = dyn_cast<ArrayType>(Val&: LHSTy);
14055	const auto *RHSATy = dyn_cast<ArrayType>(Val&: RHSTy);
14056	if ((LHSATy && LHSATy->getElementType().isWebAssemblyReferenceType()) ||
14057	(RHSATy && RHSATy->getElementType().isWebAssemblyReferenceType())) {
14058	return InvalidOperands(Loc, LHS, RHS);
14059	}
14060
14061	// Diagnose cases where the user write a logical and/or but probably meant a
14062	// bitwise one. We do this when the LHS is a non-bool integer and the RHS
14063	// is a constant.
14064	if (!EnumConstantInBoolContext && LHS.get()->getType()->isIntegerType() &&
14065	!LHS.get()->getType()->isBooleanType() &&
14066	RHS.get()->getType()->isIntegerType() && !RHS.get()->isValueDependent() &&
14067	// Don't warn in macros or template instantiations.
14068	!Loc.isMacroID() && !inTemplateInstantiation()) {
14069	// If the RHS can be constant folded, and if it constant folds to something
14070	// that isn't 0 or 1 (which indicate a potential logical operation that
14071	// happened to fold to true/false) then warn.
14072	// Parens on the RHS are ignored.
14073	Expr::EvalResult EVResult;
14074	if (RHS.get()->EvaluateAsInt(Result&: EVResult, Ctx: Context)) {
14075	llvm::APSInt Result = EVResult.Val.getInt();
14076	if ((getLangOpts().CPlusPlus && !RHS.get()->getType()->isBooleanType() &&
14077	!RHS.get()->getExprLoc().isMacroID()) ||
14078	(Result != 0 && Result != 1)) {
14079	Diag(Loc, diag::warn_logical_instead_of_bitwise)
14080	<< RHS.get()->getSourceRange() << (Opc == BO_LAnd ? "&&" : "||");
14081	// Suggest replacing the logical operator with the bitwise version
14082	Diag(Loc, diag::note_logical_instead_of_bitwise_change_operator)
14083	<< (Opc == BO_LAnd ? "&" : "|")
14084	<< FixItHint::CreateReplacement(
14085	SourceRange(Loc, getLocForEndOfToken(Loc)),
14086	Opc == BO_LAnd ? "&" : "|");
14087	if (Opc == BO_LAnd)
14088	// Suggest replacing "Foo() && kNonZero" with "Foo()"
14089	Diag(Loc, diag::note_logical_instead_of_bitwise_remove_constant)
14090	<< FixItHint::CreateRemoval(
14091	SourceRange(getLocForEndOfToken(LHS.get()->getEndLoc()),
14092	RHS.get()->getEndLoc()));
14093	}
14094	}
14095	}
14096
14097	if (!Context.getLangOpts().CPlusPlus) {
14098	// OpenCL v1.1 s6.3.g: The logical operators and (&&), or (||) do
14099	// not operate on the built-in scalar and vector float types.
14100	if (Context.getLangOpts().OpenCL &&
14101	Context.getLangOpts().OpenCLVersion < 120) {
14102	if (LHS.get()->getType()->isFloatingType() ||
14103	RHS.get()->getType()->isFloatingType())
14104	return InvalidOperands(Loc, LHS, RHS);
14105	}
14106
14107	LHS = UsualUnaryConversions(E: LHS.get());
14108	if (LHS.isInvalid())
14109	return QualType();
14110
14111	RHS = UsualUnaryConversions(E: RHS.get());
14112	if (RHS.isInvalid())
14113	return QualType();
14114
14115	if (!LHS.get()->getType()->isScalarType() ||
14116	!RHS.get()->getType()->isScalarType())
14117	return InvalidOperands(Loc, LHS, RHS);
14118
14119	return Context.IntTy;
14120	}
14121
14122	// The following is safe because we only use this method for
14123	// non-overloadable operands.
14124
14125	// C++ [expr.log.and]p1
14126	// C++ [expr.log.or]p1
14127	// The operands are both contextually converted to type bool.
14128	ExprResult LHSRes = PerformContextuallyConvertToBool(From: LHS.get());
14129	if (LHSRes.isInvalid())
14130	return InvalidOperands(Loc, LHS, RHS);
14131	LHS = LHSRes;
14132
14133	ExprResult RHSRes = PerformContextuallyConvertToBool(From: RHS.get());
14134	if (RHSRes.isInvalid())
14135	return InvalidOperands(Loc, LHS, RHS);
14136	RHS = RHSRes;
14137
14138	// C++ [expr.log.and]p2
14139	// C++ [expr.log.or]p2
14140	// The result is a bool.
14141	return Context.BoolTy;
14142	}
14143
14144	static bool IsReadonlyMessage(Expr *E, Sema &S) {
14145	const MemberExpr *ME = dyn_cast<MemberExpr>(Val: E);
14146	if (!ME) return false;
14147	if (!isa<FieldDecl>(Val: ME->getMemberDecl())) return false;
14148	ObjCMessageExpr *Base = dyn_cast<ObjCMessageExpr>(
14149	Val: ME->getBase()->IgnoreImplicit()->IgnoreParenImpCasts());
14150	if (!Base) return false;
14151	return Base->getMethodDecl() != nullptr;
14152	}
14153
14154	/// Is the given expression (which must be 'const') a reference to a
14155	/// variable which was originally non-const, but which has become
14156	/// 'const' due to being captured within a block?
14157	enum NonConstCaptureKind { NCCK_None, NCCK_Block, NCCK_Lambda };
14158	static NonConstCaptureKind isReferenceToNonConstCapture(Sema &S, Expr *E) {
14159	assert(E->isLValue() && E->getType().isConstQualified());
14160	E = E->IgnoreParens();
14161
14162	// Must be a reference to a declaration from an enclosing scope.
14163	DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: E);
14164	if (!DRE) return NCCK_None;
14165	if (!DRE->refersToEnclosingVariableOrCapture()) return NCCK_None;
14166
14167	// The declaration must be a variable which is not declared 'const'.
14168	VarDecl *var = dyn_cast<VarDecl>(Val: DRE->getDecl());
14169	if (!var) return NCCK_None;
14170	if (var->getType().isConstQualified()) return NCCK_None;
14171	assert(var->hasLocalStorage() && "capture added 'const' to non-local?");
14172
14173	// Decide whether the first capture was for a block or a lambda.
14174	DeclContext *DC = S.CurContext, *Prev = nullptr;
14175	// Decide whether the first capture was for a block or a lambda.
14176	while (DC) {
14177	// For init-capture, it is possible that the variable belongs to the
14178	// template pattern of the current context.
14179	if (auto *FD = dyn_cast<FunctionDecl>(Val: DC))
14180	if (var->isInitCapture() &&
14181	FD->getTemplateInstantiationPattern() == var->getDeclContext())
14182	break;
14183	if (DC == var->getDeclContext())
14184	break;
14185	Prev = DC;
14186	DC = DC->getParent();
14187	}
14188	// Unless we have an init-capture, we've gone one step too far.
14189	if (!var->isInitCapture())
14190	DC = Prev;
14191	return (isa<BlockDecl>(Val: DC) ? NCCK_Block : NCCK_Lambda);
14192	}
14193
14194	static bool IsTypeModifiable(QualType Ty, bool IsDereference) {
14195	Ty = Ty.getNonReferenceType();
14196	if (IsDereference && Ty->isPointerType())
14197	Ty = Ty->getPointeeType();
14198	return !Ty.isConstQualified();
14199	}
14200
14201	// Update err_typecheck_assign_const and note_typecheck_assign_const
14202	// when this enum is changed.
14203	enum {
14204	ConstFunction,
14205	ConstVariable,
14206	ConstMember,
14207	ConstMethod,
14208	NestedConstMember,
14209	ConstUnknown, // Keep as last element
14210	};
14211
14212	/// Emit the "read-only variable not assignable" error and print notes to give
14213	/// more information about why the variable is not assignable, such as pointing
14214	/// to the declaration of a const variable, showing that a method is const, or
14215	/// that the function is returning a const reference.
14216	static void DiagnoseConstAssignment(Sema &S, const Expr *E,
14217	SourceLocation Loc) {
14218	SourceRange ExprRange = E->getSourceRange();
14219
14220	// Only emit one error on the first const found. All other consts will emit
14221	// a note to the error.
14222	bool DiagnosticEmitted = false;
14223
14224	// Track if the current expression is the result of a dereference, and if the
14225	// next checked expression is the result of a dereference.
14226	bool IsDereference = false;
14227	bool NextIsDereference = false;
14228
14229	// Loop to process MemberExpr chains.
14230	while (true) {
14231	IsDereference = NextIsDereference;
14232
14233	E = E->IgnoreImplicit()->IgnoreParenImpCasts();
14234	if (const MemberExpr *ME = dyn_cast<MemberExpr>(Val: E)) {
14235	NextIsDereference = ME->isArrow();
14236	const ValueDecl *VD = ME->getMemberDecl();
14237	if (const FieldDecl *Field = dyn_cast<FieldDecl>(Val: VD)) {
14238	// Mutable fields can be modified even if the class is const.
14239	if (Field->isMutable()) {
14240	assert(DiagnosticEmitted && "Expected diagnostic not emitted.");
14241	break;
14242	}
14243
14244	if (!IsTypeModifiable(Field->getType(), IsDereference)) {
14245	if (!DiagnosticEmitted) {
14246	S.Diag(Loc, diag::err_typecheck_assign_const)
14247	<< ExprRange << ConstMember << false /*static*/ << Field
14248	<< Field->getType();
14249	DiagnosticEmitted = true;
14250	}
14251	S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
14252	<< ConstMember << false /*static*/ << Field << Field->getType()
14253	<< Field->getSourceRange();
14254	}
14255	E = ME->getBase();
14256	continue;
14257	} else if (const VarDecl *VDecl = dyn_cast<VarDecl>(Val: VD)) {
14258	if (VDecl->getType().isConstQualified()) {
14259	if (!DiagnosticEmitted) {
14260	S.Diag(Loc, diag::err_typecheck_assign_const)
14261	<< ExprRange << ConstMember << true /*static*/ << VDecl
14262	<< VDecl->getType();
14263	DiagnosticEmitted = true;
14264	}
14265	S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
14266	<< ConstMember << true /*static*/ << VDecl << VDecl->getType()
14267	<< VDecl->getSourceRange();
14268	}
14269	// Static fields do not inherit constness from parents.
14270	break;
14271	}
14272	break; // End MemberExpr
14273	} else if (const ArraySubscriptExpr *ASE =
14274	dyn_cast<ArraySubscriptExpr>(Val: E)) {
14275	E = ASE->getBase()->IgnoreParenImpCasts();
14276	continue;
14277	} else if (const ExtVectorElementExpr *EVE =
14278	dyn_cast<ExtVectorElementExpr>(Val: E)) {
14279	E = EVE->getBase()->IgnoreParenImpCasts();
14280	continue;
14281	}
14282	break;
14283	}
14284
14285	if (const CallExpr *CE = dyn_cast<CallExpr>(Val: E)) {
14286	// Function calls
14287	const FunctionDecl *FD = CE->getDirectCallee();
14288	if (FD && !IsTypeModifiable(Ty: FD->getReturnType(), IsDereference)) {
14289	if (!DiagnosticEmitted) {
14290	S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange
14291	<< ConstFunction << FD;
14292	DiagnosticEmitted = true;
14293	}
14294	S.Diag(FD->getReturnTypeSourceRange().getBegin(),
14295	diag::note_typecheck_assign_const)
14296	<< ConstFunction << FD << FD->getReturnType()
14297	<< FD->getReturnTypeSourceRange();
14298	}
14299	} else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: E)) {
14300	// Point to variable declaration.
14301	if (const ValueDecl *VD = DRE->getDecl()) {
14302	if (!IsTypeModifiable(Ty: VD->getType(), IsDereference)) {
14303	if (!DiagnosticEmitted) {
14304	S.Diag(Loc, diag::err_typecheck_assign_const)
14305	<< ExprRange << ConstVariable << VD << VD->getType();
14306	DiagnosticEmitted = true;
14307	}
14308	S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
14309	<< ConstVariable << VD << VD->getType() << VD->getSourceRange();
14310	}
14311	}
14312	} else if (isa<CXXThisExpr>(Val: E)) {
14313	if (const DeclContext *DC = S.getFunctionLevelDeclContext()) {
14314	if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Val: DC)) {
14315	if (MD->isConst()) {
14316	if (!DiagnosticEmitted) {
14317	S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange
14318	<< ConstMethod << MD;
14319	DiagnosticEmitted = true;
14320	}
14321	S.Diag(MD->getLocation(), diag::note_typecheck_assign_const)
14322	<< ConstMethod << MD << MD->getSourceRange();
14323	}
14324	}
14325	}
14326	}
14327
14328	if (DiagnosticEmitted)
14329	return;
14330
14331	// Can't determine a more specific message, so display the generic error.
14332	S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange << ConstUnknown;
14333	}
14334
14335	enum OriginalExprKind {
14336	OEK_Variable,
14337	OEK_Member,
14338	OEK_LValue
14339	};
14340
14341	static void DiagnoseRecursiveConstFields(Sema &S, const ValueDecl *VD,
14342	const RecordType *Ty,
14343	SourceLocation Loc, SourceRange Range,
14344	OriginalExprKind OEK,
14345	bool &DiagnosticEmitted) {
14346	std::vector<const RecordType *> RecordTypeList;
14347	RecordTypeList.push_back(x: Ty);
14348	unsigned NextToCheckIndex = 0;
14349	// We walk the record hierarchy breadth-first to ensure that we print
14350	// diagnostics in field nesting order.
14351	while (RecordTypeList.size() > NextToCheckIndex) {
14352	bool IsNested = NextToCheckIndex > 0;
14353	for (const FieldDecl *Field :
14354	RecordTypeList[NextToCheckIndex]->getDecl()->fields()) {
14355	// First, check every field for constness.
14356	QualType FieldTy = Field->getType();
14357	if (FieldTy.isConstQualified()) {
14358	if (!DiagnosticEmitted) {
14359	S.Diag(Loc, diag::err_typecheck_assign_const)
14360	<< Range << NestedConstMember << OEK << VD
14361	<< IsNested << Field;
14362	DiagnosticEmitted = true;
14363	}
14364	S.Diag(Field->getLocation(), diag::note_typecheck_assign_const)
14365	<< NestedConstMember << IsNested << Field
14366	<< FieldTy << Field->getSourceRange();
14367	}
14368
14369	// Then we append it to the list to check next in order.
14370	FieldTy = FieldTy.getCanonicalType();
14371	if (const auto *FieldRecTy = FieldTy->getAs<RecordType>()) {
14372	if (!llvm::is_contained(RecordTypeList, FieldRecTy))
14373	RecordTypeList.push_back(FieldRecTy);
14374	}
14375	}
14376	++NextToCheckIndex;
14377	}
14378	}
14379
14380	/// Emit an error for the case where a record we are trying to assign to has a
14381	/// const-qualified field somewhere in its hierarchy.
14382	static void DiagnoseRecursiveConstFields(Sema &S, const Expr *E,
14383	SourceLocation Loc) {
14384	QualType Ty = E->getType();
14385	assert(Ty->isRecordType() && "lvalue was not record?");
14386	SourceRange Range = E->getSourceRange();
14387	const RecordType *RTy = Ty.getCanonicalType()->getAs<RecordType>();
14388	bool DiagEmitted = false;
14389
14390	if (const MemberExpr *ME = dyn_cast<MemberExpr>(Val: E))
14391	DiagnoseRecursiveConstFields(S, VD: ME->getMemberDecl(), Ty: RTy, Loc,
14392	Range, OEK: OEK_Member, DiagnosticEmitted&: DiagEmitted);
14393	else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: E))
14394	DiagnoseRecursiveConstFields(S, VD: DRE->getDecl(), Ty: RTy, Loc,
14395	Range, OEK: OEK_Variable, DiagnosticEmitted&: DiagEmitted);
14396	else
14397	DiagnoseRecursiveConstFields(S, VD: nullptr, Ty: RTy, Loc,
14398	Range, OEK: OEK_LValue, DiagnosticEmitted&: DiagEmitted);
14399	if (!DiagEmitted)
14400	DiagnoseConstAssignment(S, E, Loc);
14401	}
14402
14403	/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not,
14404	/// emit an error and return true. If so, return false.
14405	static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) {
14406	assert(!E->hasPlaceholderType(BuiltinType::PseudoObject));
14407
14408	S.CheckShadowingDeclModification(E, Loc);
14409
14410	SourceLocation OrigLoc = Loc;
14411	Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(Ctx&: S.Context,
14412	Loc: &Loc);
14413	if (IsLV == Expr::MLV_ClassTemporary && IsReadonlyMessage(E, S))
14414	IsLV = Expr::MLV_InvalidMessageExpression;
14415	if (IsLV == Expr::MLV_Valid)
14416	return false;
14417
14418	unsigned DiagID = 0;
14419	bool NeedType = false;
14420	switch (IsLV) { // C99 6.5.16p2
14421	case Expr::MLV_ConstQualified:
14422	// Use a specialized diagnostic when we're assigning to an object
14423	// from an enclosing function or block.
14424	if (NonConstCaptureKind NCCK = isReferenceToNonConstCapture(S, E)) {
14425	if (NCCK == NCCK_Block)
14426	DiagID = diag::err_block_decl_ref_not_modifiable_lvalue;
14427	else
14428	DiagID = diag::err_lambda_decl_ref_not_modifiable_lvalue;
14429	break;
14430	}
14431
14432	// In ARC, use some specialized diagnostics for occasions where we
14433	// infer 'const'. These are always pseudo-strong variables.
14434	if (S.getLangOpts().ObjCAutoRefCount) {
14435	DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(Val: E->IgnoreParenCasts());
14436	if (declRef && isa<VarDecl>(Val: declRef->getDecl())) {
14437	VarDecl *var = cast<VarDecl>(Val: declRef->getDecl());
14438
14439	// Use the normal diagnostic if it's pseudo-__strong but the
14440	// user actually wrote 'const'.
14441	if (var->isARCPseudoStrong() &&
14442	(!var->getTypeSourceInfo() ||
14443	!var->getTypeSourceInfo()->getType().isConstQualified())) {
14444	// There are three pseudo-strong cases:
14445	// - self
14446	ObjCMethodDecl *method = S.getCurMethodDecl();
14447	if (method && var == method->getSelfDecl()) {
14448	DiagID = method->isClassMethod()
14449	? diag::err_typecheck_arc_assign_self_class_method
14450	: diag::err_typecheck_arc_assign_self;
14451
14452	// - Objective-C externally_retained attribute.
14453	} else if (var->hasAttr<ObjCExternallyRetainedAttr>() ||
14454	isa<ParmVarDecl>(var)) {
14455	DiagID = diag::err_typecheck_arc_assign_externally_retained;
14456
14457	// - fast enumeration variables
14458	} else {
14459	DiagID = diag::err_typecheck_arr_assign_enumeration;
14460	}
14461
14462	SourceRange Assign;
14463	if (Loc != OrigLoc)
14464	Assign = SourceRange(OrigLoc, OrigLoc);
14465	S.Diag(Loc, DiagID) << E->getSourceRange() << Assign;
14466	// We need to preserve the AST regardless, so migration tool
14467	// can do its job.
14468	return false;
14469	}
14470	}
14471	}
14472
14473	// If none of the special cases above are triggered, then this is a
14474	// simple const assignment.
14475	if (DiagID == 0) {
14476	DiagnoseConstAssignment(S, E, Loc);
14477	return true;
14478	}
14479
14480	break;
14481	case Expr::MLV_ConstAddrSpace:
14482	DiagnoseConstAssignment(S, E, Loc);
14483	return true;
14484	case Expr::MLV_ConstQualifiedField:
14485	DiagnoseRecursiveConstFields(S, E, Loc);
14486	return true;
14487	case Expr::MLV_ArrayType:
14488	case Expr::MLV_ArrayTemporary:
14489	DiagID = diag::err_typecheck_array_not_modifiable_lvalue;
14490	NeedType = true;
14491	break;
14492	case Expr::MLV_NotObjectType:
14493	DiagID = diag::err_typecheck_non_object_not_modifiable_lvalue;
14494	NeedType = true;
14495	break;
14496	case Expr::MLV_LValueCast:
14497	DiagID = diag::err_typecheck_lvalue_casts_not_supported;
14498	break;
14499	case Expr::MLV_Valid:
14500	llvm_unreachable("did not take early return for MLV_Valid");
14501	case Expr::MLV_InvalidExpression:
14502	case Expr::MLV_MemberFunction:
14503	case Expr::MLV_ClassTemporary:
14504	DiagID = diag::err_typecheck_expression_not_modifiable_lvalue;
14505	break;
14506	case Expr::MLV_IncompleteType:
14507	case Expr::MLV_IncompleteVoidType:
14508	return S.RequireCompleteType(Loc, E->getType(),
14509	diag::err_typecheck_incomplete_type_not_modifiable_lvalue, E);
14510	case Expr::MLV_DuplicateVectorComponents:
14511	DiagID = diag::err_typecheck_duplicate_vector_components_not_mlvalue;
14512	break;
14513	case Expr::MLV_NoSetterProperty:
14514	llvm_unreachable("readonly properties should be processed differently");
14515	case Expr::MLV_InvalidMessageExpression:
14516	DiagID = diag::err_readonly_message_assignment;
14517	break;
14518	case Expr::MLV_SubObjCPropertySetting:
14519	DiagID = diag::err_no_subobject_property_setting;
14520	break;
14521	}
14522
14523	SourceRange Assign;
14524	if (Loc != OrigLoc)
14525	Assign = SourceRange(OrigLoc, OrigLoc);
14526	if (NeedType)
14527	S.Diag(Loc, DiagID) << E->getType() << E->getSourceRange() << Assign;
14528	else
14529	S.Diag(Loc, DiagID) << E->getSourceRange() << Assign;
14530	return true;
14531	}
14532
14533	static void CheckIdentityFieldAssignment(Expr *LHSExpr, Expr *RHSExpr,
14534	SourceLocation Loc,
14535	Sema &Sema) {
14536	if (Sema.inTemplateInstantiation())
14537	return;
14538	if (Sema.isUnevaluatedContext())
14539	return;
14540	if (Loc.isInvalid() || Loc.isMacroID())
14541	return;
14542	if (LHSExpr->getExprLoc().isMacroID() || RHSExpr->getExprLoc().isMacroID())
14543	return;
14544
14545	// C / C++ fields
14546	MemberExpr *ML = dyn_cast<MemberExpr>(Val: LHSExpr);
14547	MemberExpr *MR = dyn_cast<MemberExpr>(Val: RHSExpr);
14548	if (ML && MR) {
14549	if (!(isa<CXXThisExpr>(Val: ML->getBase()) && isa<CXXThisExpr>(Val: MR->getBase())))
14550	return;
14551	const ValueDecl *LHSDecl =
14552	cast<ValueDecl>(ML->getMemberDecl()->getCanonicalDecl());
14553	const ValueDecl *RHSDecl =
14554	cast<ValueDecl>(MR->getMemberDecl()->getCanonicalDecl());
14555	if (LHSDecl != RHSDecl)
14556	return;
14557	if (LHSDecl->getType().isVolatileQualified())
14558	return;
14559	if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>())
14560	if (RefTy->getPointeeType().isVolatileQualified())
14561	return;
14562
14563	Sema.Diag(Loc, diag::warn_identity_field_assign) << 0;
14564	}
14565
14566	// Objective-C instance variables
14567	ObjCIvarRefExpr *OL = dyn_cast<ObjCIvarRefExpr>(Val: LHSExpr);
14568	ObjCIvarRefExpr *OR = dyn_cast<ObjCIvarRefExpr>(Val: RHSExpr);
14569	if (OL && OR && OL->getDecl() == OR->getDecl()) {
14570	DeclRefExpr *RL = dyn_cast<DeclRefExpr>(Val: OL->getBase()->IgnoreImpCasts());
14571	DeclRefExpr *RR = dyn_cast<DeclRefExpr>(Val: OR->getBase()->IgnoreImpCasts());
14572	if (RL && RR && RL->getDecl() == RR->getDecl())
14573	Sema.Diag(Loc, diag::warn_identity_field_assign) << 1;
14574	}
14575	}
14576
14577	// C99 6.5.16.1
14578	QualType Sema::CheckAssignmentOperands(Expr *LHSExpr, ExprResult &RHS,
14579	SourceLocation Loc,
14580	QualType CompoundType,
14581	BinaryOperatorKind Opc) {
14582	assert(!LHSExpr->hasPlaceholderType(BuiltinType::PseudoObject));
14583
14584	// Verify that LHS is a modifiable lvalue, and emit error if not.
14585	if (CheckForModifiableLvalue(E: LHSExpr, Loc, S&: *this))
14586	return QualType();
14587
14588	QualType LHSType = LHSExpr->getType();
14589	QualType RHSType = CompoundType.isNull() ? RHS.get()->getType() :
14590	CompoundType;
14591	// OpenCL v1.2 s6.1.1.1 p2:
14592	// The half data type can only be used to declare a pointer to a buffer that
14593	// contains half values
14594	if (getLangOpts().OpenCL &&
14595	!getOpenCLOptions().isAvailableOption(Ext: "cl_khr_fp16", LO: getLangOpts()) &&
14596	LHSType->isHalfType()) {
14597	Diag(Loc, diag::err_opencl_half_load_store) << 1
14598	<< LHSType.getUnqualifiedType();
14599	return QualType();
14600	}
14601
14602	// WebAssembly tables can't be used on RHS of an assignment expression.
14603	if (RHSType->isWebAssemblyTableType()) {
14604	Diag(Loc, diag::err_wasm_table_art) << 0;
14605	return QualType();
14606	}
14607
14608	AssignConvertType ConvTy;
14609	if (CompoundType.isNull()) {
14610	Expr *RHSCheck = RHS.get();
14611
14612	CheckIdentityFieldAssignment(LHSExpr, RHSExpr: RHSCheck, Loc, Sema&: *this);
14613
14614	QualType LHSTy(LHSType);
14615	ConvTy = CheckSingleAssignmentConstraints(LHSType: LHSTy, CallerRHS&: RHS);
14616	if (RHS.isInvalid())
14617	return QualType();
14618	// Special case of NSObject attributes on c-style pointer types.
14619	if (ConvTy == IncompatiblePointer &&
14620	((Context.isObjCNSObjectType(Ty: LHSType) &&
14621	RHSType->isObjCObjectPointerType()) ||
14622	(Context.isObjCNSObjectType(Ty: RHSType) &&
14623	LHSType->isObjCObjectPointerType())))
14624	ConvTy = Compatible;
14625
14626	if (ConvTy == Compatible &&
14627	LHSType->isObjCObjectType())
14628	Diag(Loc, diag::err_objc_object_assignment)
14629	<< LHSType;
14630
14631	// If the RHS is a unary plus or minus, check to see if they = and + are
14632	// right next to each other. If so, the user may have typo'd "x =+ 4"
14633	// instead of "x += 4".
14634	if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Val: RHSCheck))
14635	RHSCheck = ICE->getSubExpr();
14636	if (UnaryOperator *UO = dyn_cast<UnaryOperator>(Val: RHSCheck)) {
14637	if ((UO->getOpcode() == UO_Plus || UO->getOpcode() == UO_Minus) &&
14638	Loc.isFileID() && UO->getOperatorLoc().isFileID() &&
14639	// Only if the two operators are exactly adjacent.
14640	Loc.getLocWithOffset(Offset: 1) == UO->getOperatorLoc() &&
14641	// And there is a space or other character before the subexpr of the
14642	// unary +/-. We don't want to warn on "x=-1".
14643	Loc.getLocWithOffset(Offset: 2) != UO->getSubExpr()->getBeginLoc() &&
14644	UO->getSubExpr()->getBeginLoc().isFileID()) {
14645	Diag(Loc, diag::warn_not_compound_assign)
14646	<< (UO->getOpcode() == UO_Plus ? "+" : "-")
14647	<< SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc());
14648	}
14649	}
14650
14651	if (ConvTy == Compatible) {
14652	if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong) {
14653	// Warn about retain cycles where a block captures the LHS, but
14654	// not if the LHS is a simple variable into which the block is
14655	// being stored...unless that variable can be captured by reference!
14656	const Expr *InnerLHS = LHSExpr->IgnoreParenCasts();
14657	const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: InnerLHS);
14658	if (!DRE || DRE->getDecl()->hasAttr<BlocksAttr>())
14659	checkRetainCycles(receiver: LHSExpr, argument: RHS.get());
14660	}
14661
14662	if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong ||
14663	LHSType.isNonWeakInMRRWithObjCWeak(Context)) {
14664	// It is safe to assign a weak reference into a strong variable.
14665	// Although this code can still have problems:
14666	// id x = self.weakProp;
14667	// id y = self.weakProp;
14668	// we do not warn to warn spuriously when 'x' and 'y' are on separate
14669	// paths through the function. This should be revisited if
14670	// -Wrepeated-use-of-weak is made flow-sensitive.
14671	// For ObjCWeak only, we do not warn if the assign is to a non-weak
14672	// variable, which will be valid for the current autorelease scope.
14673	if (!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
14674	RHS.get()->getBeginLoc()))
14675	getCurFunction()->markSafeWeakUse(E: RHS.get());
14676
14677	} else if (getLangOpts().ObjCAutoRefCount || getLangOpts().ObjCWeak) {
14678	checkUnsafeExprAssigns(Loc, LHS: LHSExpr, RHS: RHS.get());
14679	}
14680	}
14681	} else {
14682	// Compound assignment "x += y"
14683	ConvTy = CheckAssignmentConstraints(Loc, LHSType, RHSType);
14684	}
14685
14686	if (DiagnoseAssignmentResult(ConvTy, Loc, DstType: LHSType, SrcType: RHSType,
14687	SrcExpr: RHS.get(), Action: AA_Assigning))
14688	return QualType();
14689
14690	CheckForNullPointerDereference(S&: *this, E: LHSExpr);
14691
14692	if (getLangOpts().CPlusPlus20 && LHSType.isVolatileQualified()) {
14693	if (CompoundType.isNull()) {
14694	// C++2a [expr.ass]p5:
14695	// A simple-assignment whose left operand is of a volatile-qualified
14696	// type is deprecated unless the assignment is either a discarded-value
14697	// expression or an unevaluated operand
14698	ExprEvalContexts.back().VolatileAssignmentLHSs.push_back(Elt: LHSExpr);
14699	}
14700	}
14701
14702	// C11 6.5.16p3: The type of an assignment expression is the type of the
14703	// left operand would have after lvalue conversion.
14704	// C11 6.3.2.1p2: ...this is called lvalue conversion. If the lvalue has
14705	// qualified type, the value has the unqualified version of the type of the
14706	// lvalue; additionally, if the lvalue has atomic type, the value has the
14707	// non-atomic version of the type of the lvalue.
14708	// C++ 5.17p1: the type of the assignment expression is that of its left
14709	// operand.
14710	return getLangOpts().CPlusPlus ? LHSType : LHSType.getAtomicUnqualifiedType();
14711	}
14712
14713	// Scenarios to ignore if expression E is:
14714	// 1. an explicit cast expression into void
14715	// 2. a function call expression that returns void
14716	static bool IgnoreCommaOperand(const Expr *E, const ASTContext &Context) {
14717	E = E->IgnoreParens();
14718
14719	if (const CastExpr *CE = dyn_cast<CastExpr>(Val: E)) {
14720	if (CE->getCastKind() == CK_ToVoid) {
14721	return true;
14722	}
14723
14724	// static_cast<void> on a dependent type will not show up as CK_ToVoid.
14725	if (CE->getCastKind() == CK_Dependent && E->getType()->isVoidType() &&
14726	CE->getSubExpr()->getType()->isDependentType()) {
14727	return true;
14728	}
14729	}
14730
14731	if (const auto *CE = dyn_cast<CallExpr>(Val: E))
14732	return CE->getCallReturnType(Ctx: Context)->isVoidType();
14733	return false;
14734	}
14735
14736	// Look for instances where it is likely the comma operator is confused with
14737	// another operator. There is an explicit list of acceptable expressions for
14738	// the left hand side of the comma operator, otherwise emit a warning.
14739	void Sema::DiagnoseCommaOperator(const Expr *LHS, SourceLocation Loc) {
14740	// No warnings in macros
14741	if (Loc.isMacroID())
14742	return;
14743
14744	// Don't warn in template instantiations.
14745	if (inTemplateInstantiation())
14746	return;
14747
14748	// Scope isn't fine-grained enough to explicitly list the specific cases, so
14749	// instead, skip more than needed, then call back into here with the
14750	// CommaVisitor in SemaStmt.cpp.
14751	// The listed locations are the initialization and increment portions
14752	// of a for loop. The additional checks are on the condition of
14753	// if statements, do/while loops, and for loops.
14754	// Differences in scope flags for C89 mode requires the extra logic.
14755	const unsigned ForIncrementFlags =
14756	getLangOpts().C99 || getLangOpts().CPlusPlus
14757	? Scope::ControlScope | Scope::ContinueScope | Scope::BreakScope
14758	: Scope::ContinueScope | Scope::BreakScope;
14759	const unsigned ForInitFlags = Scope::ControlScope | Scope::DeclScope;
14760	const unsigned ScopeFlags = getCurScope()->getFlags();
14761	if ((ScopeFlags & ForIncrementFlags) == ForIncrementFlags ||
14762	(ScopeFlags & ForInitFlags) == ForInitFlags)
14763	return;
14764
14765	// If there are multiple comma operators used together, get the RHS of the
14766	// of the comma operator as the LHS.
14767	while (const BinaryOperator *BO = dyn_cast<BinaryOperator>(Val: LHS)) {
14768	if (BO->getOpcode() != BO_Comma)
14769	break;
14770	LHS = BO->getRHS();
14771	}
14772
14773	// Only allow some expressions on LHS to not warn.
14774	if (IgnoreCommaOperand(E: LHS, Context))
14775	return;
14776
14777	Diag(Loc, diag::warn_comma_operator);
14778	Diag(LHS->getBeginLoc(), diag::note_cast_to_void)
14779	<< LHS->getSourceRange()
14780	<< FixItHint::CreateInsertion(LHS->getBeginLoc(),
14781	LangOpts.CPlusPlus ? "static_cast<void>("
14782	: "(void)(")
14783	<< FixItHint::CreateInsertion(PP.getLocForEndOfToken(LHS->getEndLoc()),
14784	")");
14785	}
14786
14787	// C99 6.5.17
14788	static QualType CheckCommaOperands(Sema &S, ExprResult &LHS, ExprResult &RHS,
14789	SourceLocation Loc) {
14790	LHS = S.CheckPlaceholderExpr(E: LHS.get());
14791	RHS = S.CheckPlaceholderExpr(E: RHS.get());
14792	if (LHS.isInvalid() || RHS.isInvalid())
14793	return QualType();
14794
14795	// C's comma performs lvalue conversion (C99 6.3.2.1) on both its
14796	// operands, but not unary promotions.
14797	// C++'s comma does not do any conversions at all (C++ [expr.comma]p1).
14798
14799	// So we treat the LHS as a ignored value, and in C++ we allow the
14800	// containing site to determine what should be done with the RHS.
14801	LHS = S.IgnoredValueConversions(E: LHS.get());
14802	if (LHS.isInvalid())
14803	return QualType();
14804
14805	S.DiagnoseUnusedExprResult(LHS.get(), diag::warn_unused_comma_left_operand);
14806
14807	if (!S.getLangOpts().CPlusPlus) {
14808	RHS = S.DefaultFunctionArrayLvalueConversion(E: RHS.get());
14809	if (RHS.isInvalid())
14810	return QualType();
14811	if (!RHS.get()->getType()->isVoidType())
14812	S.RequireCompleteType(Loc, RHS.get()->getType(),
14813	diag::err_incomplete_type);
14814	}
14815
14816	if (!S.getDiagnostics().isIgnored(diag::warn_comma_operator, Loc))
14817	S.DiagnoseCommaOperator(LHS: LHS.get(), Loc);
14818
14819	return RHS.get()->getType();
14820	}
14821
14822	/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine
14823	/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions.
14824	static QualType CheckIncrementDecrementOperand(Sema &S, Expr *Op,
14825	ExprValueKind &VK,
14826	ExprObjectKind &OK,
14827	SourceLocation OpLoc,
14828	bool IsInc, bool IsPrefix) {
14829	if (Op->isTypeDependent())
14830	return S.Context.DependentTy;
14831
14832	QualType ResType = Op->getType();
14833	// Atomic types can be used for increment / decrement where the non-atomic
14834	// versions can, so ignore the _Atomic() specifier for the purpose of
14835	// checking.
14836	if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
14837	ResType = ResAtomicType->getValueType();
14838
14839	assert(!ResType.isNull() && "no type for increment/decrement expression");
14840
14841	if (S.getLangOpts().CPlusPlus && ResType->isBooleanType()) {
14842	// Decrement of bool is not allowed.
14843	if (!IsInc) {
14844	S.Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange();
14845	return QualType();
14846	}
14847	// Increment of bool sets it to true, but is deprecated.
14848	S.Diag(OpLoc, S.getLangOpts().CPlusPlus17 ? diag::ext_increment_bool
14849	: diag::warn_increment_bool)
14850	<< Op->getSourceRange();
14851	} else if (S.getLangOpts().CPlusPlus && ResType->isEnumeralType()) {
14852	// Error on enum increments and decrements in C++ mode
14853	S.Diag(OpLoc, diag::err_increment_decrement_enum) << IsInc << ResType;
14854	return QualType();
14855	} else if (ResType->isRealType()) {
14856	// OK!
14857	} else if (ResType->isPointerType()) {
14858	// C99 6.5.2.4p2, 6.5.6p2
14859	if (!checkArithmeticOpPointerOperand(S, Loc: OpLoc, Operand: Op))
14860	return QualType();
14861	} else if (ResType->isObjCObjectPointerType()) {
14862	// On modern runtimes, ObjC pointer arithmetic is forbidden.
14863	// Otherwise, we just need a complete type.
14864	if (checkArithmeticIncompletePointerType(S, Loc: OpLoc, Operand: Op) ||
14865	checkArithmeticOnObjCPointer(S, opLoc: OpLoc, op: Op))
14866	return QualType();
14867	} else if (ResType->isAnyComplexType()) {
14868	// C99 does not support ++/-- on complex types, we allow as an extension.
14869	S.Diag(OpLoc, diag::ext_integer_increment_complex)
14870	<< ResType << Op->getSourceRange();
14871	} else if (ResType->isPlaceholderType()) {
14872	ExprResult PR = S.CheckPlaceholderExpr(E: Op);
14873	if (PR.isInvalid()) return QualType();
14874	return CheckIncrementDecrementOperand(S, Op: PR.get(), VK, OK, OpLoc,
14875	IsInc, IsPrefix);
14876	} else if (S.getLangOpts().AltiVec && ResType->isVectorType()) {
14877	// OK! ( C/C++ Language Extensions for CBEA(Version 2.6) 10.3 )
14878	} else if (S.getLangOpts().ZVector && ResType->isVectorType() &&
14879	(ResType->castAs<VectorType>()->getVectorKind() !=
14880	VectorKind::AltiVecBool)) {
14881	// The z vector extensions allow ++ and -- for non-bool vectors.
14882	} else if (S.getLangOpts().OpenCL && ResType->isVectorType() &&
14883	ResType->castAs<VectorType>()->getElementType()->isIntegerType()) {
14884	// OpenCL V1.2 6.3 says dec/inc ops operate on integer vector types.
14885	} else {
14886	S.Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement)
14887	<< ResType << int(IsInc) << Op->getSourceRange();
14888	return QualType();
14889	}
14890	// At this point, we know we have a real, complex or pointer type.
14891	// Now make sure the operand is a modifiable lvalue.
14892	if (CheckForModifiableLvalue(E: Op, Loc: OpLoc, S))
14893	return QualType();
14894	if (S.getLangOpts().CPlusPlus20 && ResType.isVolatileQualified()) {
14895	// C++2a [expr.pre.inc]p1, [expr.post.inc]p1:
14896	// An operand with volatile-qualified type is deprecated
14897	S.Diag(OpLoc, diag::warn_deprecated_increment_decrement_volatile)
14898	<< IsInc << ResType;
14899	}
14900	// In C++, a prefix increment is the same type as the operand. Otherwise
14901	// (in C or with postfix), the increment is the unqualified type of the
14902	// operand.
14903	if (IsPrefix && S.getLangOpts().CPlusPlus) {
14904	VK = VK_LValue;
14905	OK = Op->getObjectKind();
14906	return ResType;
14907	} else {
14908	VK = VK_PRValue;
14909	return ResType.getUnqualifiedType();
14910	}
14911	}
14912
14913
14914	/// getPrimaryDecl - Helper function for CheckAddressOfOperand().
14915	/// This routine allows us to typecheck complex/recursive expressions
14916	/// where the declaration is needed for type checking. We only need to
14917	/// handle cases when the expression references a function designator
14918	/// or is an lvalue. Here are some examples:
14919	/// - &(x) => x
14920	/// - &*****f => f for f a function designator.
14921	/// - &s.xx => s
14922	/// - &s.zz[1].yy -> s, if zz is an array
14923	/// - *(x + 1) -> x, if x is an array
14924	/// - &"123"[2] -> 0
14925	/// - & __real__ x -> x
14926	///
14927	/// FIXME: We don't recurse to the RHS of a comma, nor handle pointers to
14928	/// members.
14929	static ValueDecl *getPrimaryDecl(Expr *E) {
14930	switch (E->getStmtClass()) {
14931	case Stmt::DeclRefExprClass:
14932	return cast<DeclRefExpr>(Val: E)->getDecl();
14933	case Stmt::MemberExprClass:
14934	// If this is an arrow operator, the address is an offset from
14935	// the base's value, so the object the base refers to is
14936	// irrelevant.
14937	if (cast<MemberExpr>(Val: E)->isArrow())
14938	return nullptr;
14939	// Otherwise, the expression refers to a part of the base
14940	return getPrimaryDecl(E: cast<MemberExpr>(Val: E)->getBase());
14941	case Stmt::ArraySubscriptExprClass: {
14942	// FIXME: This code shouldn't be necessary! We should catch the implicit
14943	// promotion of register arrays earlier.
14944	Expr* Base = cast<ArraySubscriptExpr>(Val: E)->getBase();
14945	if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Val: Base)) {
14946	if (ICE->getSubExpr()->getType()->isArrayType())
14947	return getPrimaryDecl(ICE->getSubExpr());
14948	}
14949	return nullptr;
14950	}
14951	case Stmt::UnaryOperatorClass: {
14952	UnaryOperator *UO = cast<UnaryOperator>(Val: E);
14953
14954	switch(UO->getOpcode()) {
14955	case UO_Real:
14956	case UO_Imag:
14957	case UO_Extension:
14958	return getPrimaryDecl(E: UO->getSubExpr());
14959	default:
14960	return nullptr;
14961	}
14962	}
14963	case Stmt::ParenExprClass:
14964	return getPrimaryDecl(E: cast<ParenExpr>(Val: E)->getSubExpr());
14965	case Stmt::ImplicitCastExprClass:
14966	// If the result of an implicit cast is an l-value, we care about
14967	// the sub-expression; otherwise, the result here doesn't matter.
14968	return getPrimaryDecl(cast<ImplicitCastExpr>(Val: E)->getSubExpr());
14969	case Stmt::CXXUuidofExprClass:
14970	return cast<CXXUuidofExpr>(Val: E)->getGuidDecl();
14971	default:
14972	return nullptr;
14973	}
14974	}
14975
14976	namespace {
14977	enum {
14978	AO_Bit_Field = 0,
14979	AO_Vector_Element = 1,
14980	AO_Property_Expansion = 2,
14981	AO_Register_Variable = 3,
14982	AO_Matrix_Element = 4,
14983	AO_No_Error = 5
14984	};
14985	}
14986	/// Diagnose invalid operand for address of operations.
14987	///
14988	/// \param Type The type of operand which cannot have its address taken.
14989	static void diagnoseAddressOfInvalidType(Sema &S, SourceLocation Loc,
14990	Expr *E, unsigned Type) {
14991	S.Diag(Loc, diag::err_typecheck_address_of) << Type << E->getSourceRange();
14992	}
14993
14994	bool Sema::CheckUseOfCXXMethodAsAddressOfOperand(SourceLocation OpLoc,
14995	const Expr *Op,
14996	const CXXMethodDecl *MD) {
14997	const auto *DRE = cast<DeclRefExpr>(Val: Op->IgnoreParens());
14998
14999	if (Op != DRE)
15000	return Diag(OpLoc, diag::err_parens_pointer_member_function)
15001	<< Op->getSourceRange();
15002
15003	// Taking the address of a dtor is illegal per C++ [class.dtor]p2.
15004	if (isa<CXXDestructorDecl>(MD))
15005	return Diag(OpLoc, diag::err_typecheck_addrof_dtor)
15006	<< DRE->getSourceRange();
15007
15008	if (DRE->getQualifier())
15009	return false;
15010
15011	if (MD->getParent()->getName().empty())
15012	return Diag(OpLoc, diag::err_unqualified_pointer_member_function)
15013	<< DRE->getSourceRange();
15014
15015	SmallString<32> Str;
15016	StringRef Qual = (MD->getParent()->getName() + "::").toStringRef(Str);
15017	return Diag(OpLoc, diag::err_unqualified_pointer_member_function)
15018	<< DRE->getSourceRange()
15019	<< FixItHint::CreateInsertion(DRE->getSourceRange().getBegin(), Qual);
15020	}
15021
15022	/// CheckAddressOfOperand - The operand of & must be either a function
15023	/// designator or an lvalue designating an object. If it is an lvalue, the
15024	/// object cannot be declared with storage class register or be a bit field.
15025	/// Note: The usual conversions are *not* applied to the operand of the &
15026	/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue.
15027	/// In C++, the operand might be an overloaded function name, in which case
15028	/// we allow the '&' but retain the overloaded-function type.
15029	QualType Sema::CheckAddressOfOperand(ExprResult &OrigOp, SourceLocation OpLoc) {
15030	if (const BuiltinType *PTy = OrigOp.get()->getType()->getAsPlaceholderType()){
15031	if (PTy->getKind() == BuiltinType::Overload) {
15032	Expr *E = OrigOp.get()->IgnoreParens();
15033	if (!isa<OverloadExpr>(Val: E)) {
15034	assert(cast<UnaryOperator>(E)->getOpcode() == UO_AddrOf);
15035	Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof_addrof_function)
15036	<< OrigOp.get()->getSourceRange();
15037	return QualType();
15038	}
15039
15040	OverloadExpr *Ovl = cast<OverloadExpr>(Val: E);
15041	if (isa<UnresolvedMemberExpr>(Val: Ovl))
15042	if (!ResolveSingleFunctionTemplateSpecialization(ovl: Ovl)) {
15043	Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
15044	<< OrigOp.get()->getSourceRange();
15045	return QualType();
15046	}
15047
15048	return Context.OverloadTy;
15049	}
15050
15051	if (PTy->getKind() == BuiltinType::UnknownAny)
15052	return Context.UnknownAnyTy;
15053
15054	if (PTy->getKind() == BuiltinType::BoundMember) {
15055	Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
15056	<< OrigOp.get()->getSourceRange();
15057	return QualType();
15058	}
15059
15060	OrigOp = CheckPlaceholderExpr(E: OrigOp.get());
15061	if (OrigOp.isInvalid()) return QualType();
15062	}
15063
15064	if (OrigOp.get()->isTypeDependent())
15065	return Context.DependentTy;
15066
15067	assert(!OrigOp.get()->hasPlaceholderType());
15068
15069	// Make sure to ignore parentheses in subsequent checks
15070	Expr *op = OrigOp.get()->IgnoreParens();
15071
15072	// In OpenCL captures for blocks called as lambda functions
15073	// are located in the private address space. Blocks used in
15074	// enqueue_kernel can be located in a different address space
15075	// depending on a vendor implementation. Thus preventing
15076	// taking an address of the capture to avoid invalid AS casts.
15077	if (LangOpts.OpenCL) {
15078	auto* VarRef = dyn_cast<DeclRefExpr>(Val: op);
15079	if (VarRef && VarRef->refersToEnclosingVariableOrCapture()) {
15080	Diag(op->getExprLoc(), diag::err_opencl_taking_address_capture);
15081	return QualType();
15082	}
15083	}
15084
15085	if (getLangOpts().C99) {
15086	// Implement C99-only parts of addressof rules.
15087	if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(Val: op)) {
15088	if (uOp->getOpcode() == UO_Deref)
15089	// Per C99 6.5.3.2, the address of a deref always returns a valid result
15090	// (assuming the deref expression is valid).
15091	return uOp->getSubExpr()->getType();
15092	}
15093	// Technically, there should be a check for array subscript
15094	// expressions here, but the result of one is always an lvalue anyway.
15095	}
15096	ValueDecl *dcl = getPrimaryDecl(E: op);
15097
15098	if (auto *FD = dyn_cast_or_null<FunctionDecl>(Val: dcl))
15099	if (!checkAddressOfFunctionIsAvailable(Function: FD, /*Complain=*/true,
15100	Loc: op->getBeginLoc()))
15101	return QualType();
15102
15103	Expr::LValueClassification lval = op->ClassifyLValue(Ctx&: Context);
15104	unsigned AddressOfError = AO_No_Error;
15105
15106	if (lval == Expr::LV_ClassTemporary || lval == Expr::LV_ArrayTemporary) {
15107	bool sfinae = (bool)isSFINAEContext();
15108	Diag(OpLoc, isSFINAEContext() ? diag::err_typecheck_addrof_temporary
15109	: diag::ext_typecheck_addrof_temporary)
15110	<< op->getType() << op->getSourceRange();
15111	if (sfinae)
15112	return QualType();
15113	// Materialize the temporary as an lvalue so that we can take its address.
15114	OrigOp = op =
15115	CreateMaterializeTemporaryExpr(T: op->getType(), Temporary: OrigOp.get(), BoundToLvalueReference: true);
15116	} else if (isa<ObjCSelectorExpr>(Val: op)) {
15117	return Context.getPointerType(T: op->getType());
15118	} else if (lval == Expr::LV_MemberFunction) {
15119	// If it's an instance method, make a member pointer.
15120	// The expression must have exactly the form &A::foo.
15121
15122	// If the underlying expression isn't a decl ref, give up.
15123	if (!isa<DeclRefExpr>(Val: op)) {
15124	Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
15125	<< OrigOp.get()->getSourceRange();
15126	return QualType();
15127	}
15128	DeclRefExpr *DRE = cast<DeclRefExpr>(Val: op);
15129	CXXMethodDecl *MD = cast<CXXMethodDecl>(Val: DRE->getDecl());
15130
15131	CheckUseOfCXXMethodAsAddressOfOperand(OpLoc, Op: OrigOp.get(), MD);
15132
15133	QualType MPTy = Context.getMemberPointerType(
15134	T: op->getType(), Cls: Context.getTypeDeclType(MD->getParent()).getTypePtr());
15135	// Under the MS ABI, lock down the inheritance model now.
15136	if (Context.getTargetInfo().getCXXABI().isMicrosoft())
15137	(void)isCompleteType(Loc: OpLoc, T: MPTy);
15138	return MPTy;
15139	} else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) {
15140	// C99 6.5.3.2p1
15141	// The operand must be either an l-value or a function designator
15142	if (!op->getType()->isFunctionType()) {
15143	// Use a special diagnostic for loads from property references.
15144	if (isa<PseudoObjectExpr>(Val: op)) {
15145	AddressOfError = AO_Property_Expansion;
15146	} else {
15147	Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof)
15148	<< op->getType() << op->getSourceRange();
15149	return QualType();
15150	}
15151	} else if (const auto *DRE = dyn_cast<DeclRefExpr>(Val: op)) {
15152	if (const auto *MD = dyn_cast_or_null<CXXMethodDecl>(Val: DRE->getDecl()))
15153	CheckUseOfCXXMethodAsAddressOfOperand(OpLoc, Op: OrigOp.get(), MD);
15154	}
15155
15156	} else if (op->getObjectKind() == OK_BitField) { // C99 6.5.3.2p1
15157	// The operand cannot be a bit-field
15158	AddressOfError = AO_Bit_Field;
15159	} else if (op->getObjectKind() == OK_VectorComponent) {
15160	// The operand cannot be an element of a vector
15161	AddressOfError = AO_Vector_Element;
15162	} else if (op->getObjectKind() == OK_MatrixComponent) {
15163	// The operand cannot be an element of a matrix.
15164	AddressOfError = AO_Matrix_Element;
15165	} else if (dcl) { // C99 6.5.3.2p1
15166	// We have an lvalue with a decl. Make sure the decl is not declared
15167	// with the register storage-class specifier.
15168	if (const VarDecl *vd = dyn_cast<VarDecl>(Val: dcl)) {
15169	// in C++ it is not error to take address of a register
15170	// variable (c++03 7.1.1P3)
15171	if (vd->getStorageClass() == SC_Register &&
15172	!getLangOpts().CPlusPlus) {
15173	AddressOfError = AO_Register_Variable;
15174	}
15175	} else if (isa<MSPropertyDecl>(Val: dcl)) {
15176	AddressOfError = AO_Property_Expansion;
15177	} else if (isa<FunctionTemplateDecl>(Val: dcl)) {
15178	return Context.OverloadTy;
15179	} else if (isa<FieldDecl>(Val: dcl) || isa<IndirectFieldDecl>(Val: dcl)) {
15180	// Okay: we can take the address of a field.
15181	// Could be a pointer to member, though, if there is an explicit
15182	// scope qualifier for the class.
15183	if (isa<DeclRefExpr>(Val: op) && cast<DeclRefExpr>(Val: op)->getQualifier()) {
15184	DeclContext *Ctx = dcl->getDeclContext();
15185	if (Ctx && Ctx->isRecord()) {
15186	if (dcl->getType()->isReferenceType()) {
15187	Diag(OpLoc,
15188	diag::err_cannot_form_pointer_to_member_of_reference_type)
15189	<< dcl->getDeclName() << dcl->getType();
15190	return QualType();
15191	}
15192
15193	while (cast<RecordDecl>(Val: Ctx)->isAnonymousStructOrUnion())
15194	Ctx = Ctx->getParent();
15195
15196	QualType MPTy = Context.getMemberPointerType(
15197	T: op->getType(),
15198	Cls: Context.getTypeDeclType(cast<RecordDecl>(Val: Ctx)).getTypePtr());
15199	// Under the MS ABI, lock down the inheritance model now.
15200	if (Context.getTargetInfo().getCXXABI().isMicrosoft())
15201	(void)isCompleteType(Loc: OpLoc, T: MPTy);
15202	return MPTy;
15203	}
15204	}
15205	} else if (!isa<FunctionDecl, NonTypeTemplateParmDecl, BindingDecl,
15206	MSGuidDecl, UnnamedGlobalConstantDecl>(Val: dcl))
15207	llvm_unreachable("Unknown/unexpected decl type");
15208	}
15209
15210	if (AddressOfError != AO_No_Error) {
15211	diagnoseAddressOfInvalidType(S&: *this, Loc: OpLoc, E: op, Type: AddressOfError);
15212	return QualType();
15213	}
15214
15215	if (lval == Expr::LV_IncompleteVoidType) {
15216	// Taking the address of a void variable is technically illegal, but we
15217	// allow it in cases which are otherwise valid.
15218	// Example: "extern void x; void* y = &x;".
15219	Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange();
15220	}
15221
15222	// If the operand has type "type", the result has type "pointer to type".
15223	if (op->getType()->isObjCObjectType())
15224	return Context.getObjCObjectPointerType(OIT: op->getType());
15225
15226	// Cannot take the address of WebAssembly references or tables.
15227	if (Context.getTargetInfo().getTriple().isWasm()) {
15228	QualType OpTy = op->getType();
15229	if (OpTy.isWebAssemblyReferenceType()) {
15230	Diag(OpLoc, diag::err_wasm_ca_reference)
15231	<< 1 << OrigOp.get()->getSourceRange();
15232	return QualType();
15233	}
15234	if (OpTy->isWebAssemblyTableType()) {
15235	Diag(OpLoc, diag::err_wasm_table_pr)
15236	<< 1 << OrigOp.get()->getSourceRange();
15237	return QualType();
15238	}
15239	}
15240
15241	CheckAddressOfPackedMember(rhs: op);
15242
15243	return Context.getPointerType(T: op->getType());
15244	}
15245
15246	static void RecordModifiableNonNullParam(Sema &S, const Expr *Exp) {
15247	const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: Exp);
15248	if (!DRE)
15249	return;
15250	const Decl *D = DRE->getDecl();
15251	if (!D)
15252	return;
15253	const ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Val: D);
15254	if (!Param)
15255	return;
15256	if (const FunctionDecl* FD = dyn_cast<FunctionDecl>(Param->getDeclContext()))
15257	if (!FD->hasAttr<NonNullAttr>() && !Param->hasAttr<NonNullAttr>())
15258	return;
15259	if (FunctionScopeInfo *FD = S.getCurFunction())
15260	FD->ModifiedNonNullParams.insert(Ptr: Param);
15261	}
15262
15263	/// CheckIndirectionOperand - Type check unary indirection (prefix '*').
15264	static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK,
15265	SourceLocation OpLoc,
15266	bool IsAfterAmp = false) {
15267	if (Op->isTypeDependent())
15268	return S.Context.DependentTy;
15269
15270	ExprResult ConvResult = S.UsualUnaryConversions(E: Op);
15271	if (ConvResult.isInvalid())
15272	return QualType();
15273	Op = ConvResult.get();
15274	QualType OpTy = Op->getType();
15275	QualType Result;
15276
15277	if (isa<CXXReinterpretCastExpr>(Val: Op)) {
15278	QualType OpOrigType = Op->IgnoreParenCasts()->getType();
15279	S.CheckCompatibleReinterpretCast(SrcType: OpOrigType, DestType: OpTy, /*IsDereference*/true,
15280	Range: Op->getSourceRange());
15281	}
15282
15283	if (const PointerType *PT = OpTy->getAs<PointerType>())
15284	{
15285	Result = PT->getPointeeType();
15286	}
15287	else if (const ObjCObjectPointerType *OPT =
15288	OpTy->getAs<ObjCObjectPointerType>())
15289	Result = OPT->getPointeeType();
15290	else {
15291	ExprResult PR = S.CheckPlaceholderExpr(E: Op);
15292	if (PR.isInvalid()) return QualType();
15293	if (PR.get() != Op)
15294	return CheckIndirectionOperand(S, Op: PR.get(), VK, OpLoc);
15295	}
15296
15297	if (Result.isNull()) {
15298	S.Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer)
15299	<< OpTy << Op->getSourceRange();
15300	return QualType();
15301	}
15302
15303	if (Result->isVoidType()) {
15304	// C++ [expr.unary.op]p1:
15305	// [...] the expression to which [the unary * operator] is applied shall
15306	// be a pointer to an object type, or a pointer to a function type
15307	LangOptions LO = S.getLangOpts();
15308	if (LO.CPlusPlus)
15309	S.Diag(OpLoc, diag::err_typecheck_indirection_through_void_pointer_cpp)
15310	<< OpTy << Op->getSourceRange();
15311	else if (!(LO.C99 && IsAfterAmp) && !S.isUnevaluatedContext())
15312	S.Diag(OpLoc, diag::ext_typecheck_indirection_through_void_pointer)
15313	<< OpTy << Op->getSourceRange();
15314	}
15315
15316	// Dereferences are usually l-values...
15317	VK = VK_LValue;
15318
15319	// ...except that certain expressions are never l-values in C.
15320	if (!S.getLangOpts().CPlusPlus && Result.isCForbiddenLValueType())
15321	VK = VK_PRValue;
15322
15323	return Result;
15324	}
15325
15326	BinaryOperatorKind Sema::ConvertTokenKindToBinaryOpcode(tok::TokenKind Kind) {
15327	BinaryOperatorKind Opc;
15328	switch (Kind) {
15329	default: llvm_unreachable("Unknown binop!");
15330	case tok::periodstar: Opc = BO_PtrMemD; break;
15331	case tok::arrowstar: Opc = BO_PtrMemI; break;
15332	case tok::star: Opc = BO_Mul; break;
15333	case tok::slash: Opc = BO_Div; break;
15334	case tok::percent: Opc = BO_Rem; break;
15335	case tok::plus: Opc = BO_Add; break;
15336	case tok::minus: Opc = BO_Sub; break;
15337	case tok::lessless: Opc = BO_Shl; break;
15338	case tok::greatergreater: Opc = BO_Shr; break;
15339	case tok::lessequal: Opc = BO_LE; break;
15340	case tok::less: Opc = BO_LT; break;
15341	case tok::greaterequal: Opc = BO_GE; break;
15342	case tok::greater: Opc = BO_GT; break;
15343	case tok::exclaimequal: Opc = BO_NE; break;
15344	case tok::equalequal: Opc = BO_EQ; break;
15345	case tok::spaceship: Opc = BO_Cmp; break;
15346	case tok::amp: Opc = BO_And; break;
15347	case tok::caret: Opc = BO_Xor; break;
15348	case tok::pipe: Opc = BO_Or; break;
15349	case tok::ampamp: Opc = BO_LAnd; break;
15350	case tok::pipepipe: Opc = BO_LOr; break;
15351	case tok::equal: Opc = BO_Assign; break;
15352	case tok::starequal: Opc = BO_MulAssign; break;
15353	case tok::slashequal: Opc = BO_DivAssign; break;
15354	case tok::percentequal: Opc = BO_RemAssign; break;
15355	case tok::plusequal: Opc = BO_AddAssign; break;
15356	case tok::minusequal: Opc = BO_SubAssign; break;
15357	case tok::lesslessequal: Opc = BO_ShlAssign; break;
15358	case tok::greatergreaterequal: Opc = BO_ShrAssign; break;
15359	case tok::ampequal: Opc = BO_AndAssign; break;
15360	case tok::caretequal: Opc = BO_XorAssign; break;
15361	case tok::pipeequal: Opc = BO_OrAssign; break;
15362	case tok::comma: Opc = BO_Comma; break;
15363	}
15364	return Opc;
15365	}
15366
15367	static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode(
15368	tok::TokenKind Kind) {
15369	UnaryOperatorKind Opc;
15370	switch (Kind) {
15371	default: llvm_unreachable("Unknown unary op!");
15372	case tok::plusplus: Opc = UO_PreInc; break;
15373	case tok::minusminus: Opc = UO_PreDec; break;
15374	case tok::amp: Opc = UO_AddrOf; break;
15375	case tok::star: Opc = UO_Deref; break;
15376	case tok::plus: Opc = UO_Plus; break;
15377	case tok::minus: Opc = UO_Minus; break;
15378	case tok::tilde: Opc = UO_Not; break;
15379	case tok::exclaim: Opc = UO_LNot; break;
15380	case tok::kw___real: Opc = UO_Real; break;
15381	case tok::kw___imag: Opc = UO_Imag; break;
15382	case tok::kw___extension__: Opc = UO_Extension; break;
15383	}
15384	return Opc;
15385	}
15386
15387	const FieldDecl *
15388	Sema::getSelfAssignmentClassMemberCandidate(const ValueDecl *SelfAssigned) {
15389	// Explore the case for adding 'this->' to the LHS of a self assignment, very
15390	// common for setters.
15391	// struct A {
15392	// int X;
15393	// -void setX(int X) { X = X; }
15394	// +void setX(int X) { this->X = X; }
15395	// };
15396
15397	// Only consider parameters for self assignment fixes.
15398	if (!isa<ParmVarDecl>(Val: SelfAssigned))
15399	return nullptr;
15400	const auto *Method =
15401	dyn_cast_or_null<CXXMethodDecl>(Val: getCurFunctionDecl(AllowLambda: true));
15402	if (!Method)
15403	return nullptr;
15404
15405	const CXXRecordDecl *Parent = Method->getParent();
15406	// In theory this is fixable if the lambda explicitly captures this, but
15407	// that's added complexity that's rarely going to be used.
15408	if (Parent->isLambda())
15409	return nullptr;
15410
15411	// FIXME: Use an actual Lookup operation instead of just traversing fields
15412	// in order to get base class fields.
15413	auto Field =
15414	llvm::find_if(Parent->fields(),
15415	[Name(SelfAssigned->getDeclName())](const FieldDecl *F) {
15416	return F->getDeclName() == Name;
15417	});
15418	return (Field != Parent->field_end()) ? *Field : nullptr;
15419	}
15420
15421	/// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself.
15422	/// This warning suppressed in the event of macro expansions.
15423	static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr,
15424	SourceLocation OpLoc, bool IsBuiltin) {
15425	if (S.inTemplateInstantiation())
15426	return;
15427	if (S.isUnevaluatedContext())
15428	return;
15429	if (OpLoc.isInvalid() || OpLoc.isMacroID())
15430	return;
15431	LHSExpr = LHSExpr->IgnoreParenImpCasts();
15432	RHSExpr = RHSExpr->IgnoreParenImpCasts();
15433	const DeclRefExpr *LHSDeclRef = dyn_cast<DeclRefExpr>(Val: LHSExpr);
15434	const DeclRefExpr *RHSDeclRef = dyn_cast<DeclRefExpr>(Val: RHSExpr);
15435	if (!LHSDeclRef || !RHSDeclRef ||
15436	LHSDeclRef->getLocation().isMacroID() ||
15437	RHSDeclRef->getLocation().isMacroID())
15438	return;
15439	const ValueDecl *LHSDecl =
15440	cast<ValueDecl>(LHSDeclRef->getDecl()->getCanonicalDecl());
15441	const ValueDecl *RHSDecl =
15442	cast<ValueDecl>(RHSDeclRef->getDecl()->getCanonicalDecl());
15443	if (LHSDecl != RHSDecl)
15444	return;
15445	if (LHSDecl->getType().isVolatileQualified())
15446	return;
15447	if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>())
15448	if (RefTy->getPointeeType().isVolatileQualified())
15449	return;
15450
15451	auto Diag = S.Diag(OpLoc, IsBuiltin ? diag::warn_self_assignment_builtin
15452	: diag::warn_self_assignment_overloaded)
15453	<< LHSDeclRef->getType() << LHSExpr->getSourceRange()
15454	<< RHSExpr->getSourceRange();
15455	if (const FieldDecl *SelfAssignField =
15456	S.getSelfAssignmentClassMemberCandidate(SelfAssigned: RHSDecl))
15457	Diag << 1 << SelfAssignField
15458	<< FixItHint::CreateInsertion(InsertionLoc: LHSDeclRef->getBeginLoc(), Code: "this->");
15459	else
15460	Diag << 0;
15461	}
15462
15463	/// Check if a bitwise-& is performed on an Objective-C pointer. This
15464	/// is usually indicative of introspection within the Objective-C pointer.
15465	static void checkObjCPointerIntrospection(Sema &S, ExprResult &L, ExprResult &R,
15466	SourceLocation OpLoc) {
15467	if (!S.getLangOpts().ObjC)
15468	return;
15469
15470	const Expr *ObjCPointerExpr = nullptr, *OtherExpr = nullptr;
15471	const Expr *LHS = L.get();
15472	const Expr *RHS = R.get();
15473
15474	if (LHS->IgnoreParenCasts()->getType()->isObjCObjectPointerType()) {
15475	ObjCPointerExpr = LHS;
15476	OtherExpr = RHS;
15477	}
15478	else if (RHS->IgnoreParenCasts()->getType()->isObjCObjectPointerType()) {
15479	ObjCPointerExpr = RHS;
15480	OtherExpr = LHS;
15481	}
15482
15483	// This warning is deliberately made very specific to reduce false
15484	// positives with logic that uses '&' for hashing. This logic mainly
15485	// looks for code trying to introspect into tagged pointers, which
15486	// code should generally never do.
15487	if (ObjCPointerExpr && isa<IntegerLiteral>(Val: OtherExpr->IgnoreParenCasts())) {
15488	unsigned Diag = diag::warn_objc_pointer_masking;
15489	// Determine if we are introspecting the result of performSelectorXXX.
15490	const Expr *Ex = ObjCPointerExpr->IgnoreParenCasts();
15491	// Special case messages to -performSelector and friends, which
15492	// can return non-pointer values boxed in a pointer value.
15493	// Some clients may wish to silence warnings in this subcase.
15494	if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(Val: Ex)) {
15495	Selector S = ME->getSelector();
15496	StringRef SelArg0 = S.getNameForSlot(argIndex: 0);
15497	if (SelArg0.starts_with("performSelector"))
15498	Diag = diag::warn_objc_pointer_masking_performSelector;
15499	}
15500
15501	S.Diag(Loc: OpLoc, DiagID: Diag)
15502	<< ObjCPointerExpr->getSourceRange();
15503	}
15504	}
15505
15506	static NamedDecl *getDeclFromExpr(Expr *E) {
15507	if (!E)
15508	return nullptr;
15509	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: E))
15510	return DRE->getDecl();
15511	if (auto *ME = dyn_cast<MemberExpr>(Val: E))
15512	return ME->getMemberDecl();
15513	if (auto *IRE = dyn_cast<ObjCIvarRefExpr>(Val: E))
15514	return IRE->getDecl();
15515	return nullptr;
15516	}
15517
15518	// This helper function promotes a binary operator's operands (which are of a
15519	// half vector type) to a vector of floats and then truncates the result to
15520	// a vector of either half or short.
15521	static ExprResult convertHalfVecBinOp(Sema &S, ExprResult LHS, ExprResult RHS,
15522	BinaryOperatorKind Opc, QualType ResultTy,
15523	ExprValueKind VK, ExprObjectKind OK,
15524	bool IsCompAssign, SourceLocation OpLoc,
15525	FPOptionsOverride FPFeatures) {
15526	auto &Context = S.getASTContext();
15527	assert((isVector(ResultTy, Context.HalfTy) ||
15528	isVector(ResultTy, Context.ShortTy)) &&
15529	"Result must be a vector of half or short");
15530	assert(isVector(LHS.get()->getType(), Context.HalfTy) &&
15531	isVector(RHS.get()->getType(), Context.HalfTy) &&
15532	"both operands expected to be a half vector");
15533
15534	RHS = convertVector(RHS.get(), Context.FloatTy, S);
15535	QualType BinOpResTy = RHS.get()->getType();
15536
15537	// If Opc is a comparison, ResultType is a vector of shorts. In that case,
15538	// change BinOpResTy to a vector of ints.
15539	if (isVector(ResultTy, Context.ShortTy))
15540	BinOpResTy = S.GetSignedVectorType(V: BinOpResTy);
15541
15542	if (IsCompAssign)
15543	return CompoundAssignOperator::Create(C: Context, lhs: LHS.get(), rhs: RHS.get(), opc: Opc,
15544	ResTy: ResultTy, VK, OK, opLoc: OpLoc, FPFeatures,
15545	CompLHSType: BinOpResTy, CompResultType: BinOpResTy);
15546
15547	LHS = convertVector(LHS.get(), Context.FloatTy, S);
15548	auto *BO = BinaryOperator::Create(C: Context, lhs: LHS.get(), rhs: RHS.get(), opc: Opc,
15549	ResTy: BinOpResTy, VK, OK, opLoc: OpLoc, FPFeatures);
15550	return convertVector(BO, ResultTy->castAs<VectorType>()->getElementType(), S);
15551	}
15552
15553	static std::pair<ExprResult, ExprResult>
15554	CorrectDelayedTyposInBinOp(Sema &S, BinaryOperatorKind Opc, Expr *LHSExpr,
15555	Expr *RHSExpr) {
15556	ExprResult LHS = LHSExpr, RHS = RHSExpr;
15557	if (!S.Context.isDependenceAllowed()) {
15558	// C cannot handle TypoExpr nodes on either side of a binop because it
15559	// doesn't handle dependent types properly, so make sure any TypoExprs have
15560	// been dealt with before checking the operands.
15561	LHS = S.CorrectDelayedTyposInExpr(ER: LHS);
15562	RHS = S.CorrectDelayedTyposInExpr(
15563	RHS, /*InitDecl=*/nullptr, /*RecoverUncorrectedTypos=*/false,
15564	[Opc, LHS](Expr *E) {
15565	if (Opc != BO_Assign)
15566	return ExprResult(E);
15567	// Avoid correcting the RHS to the same Expr as the LHS.
15568	Decl *D = getDeclFromExpr(E);
15569	return (D && D == getDeclFromExpr(LHS.get())) ? ExprError() : E;
15570	});
15571	}
15572	return std::make_pair(x&: LHS, y&: RHS);
15573	}
15574
15575	/// Returns true if conversion between vectors of halfs and vectors of floats
15576	/// is needed.
15577	static bool needsConversionOfHalfVec(bool OpRequiresConversion, ASTContext &Ctx,
15578	Expr *E0, Expr *E1 = nullptr) {
15579	if (!OpRequiresConversion || Ctx.getLangOpts().NativeHalfType ||
15580	Ctx.getTargetInfo().useFP16ConversionIntrinsics())
15581	return false;
15582
15583	auto HasVectorOfHalfType = [&Ctx](Expr *E) {
15584	QualType Ty = E->IgnoreImplicit()->getType();
15585
15586	// Don't promote half precision neon vectors like float16x4_t in arm_neon.h
15587	// to vectors of floats. Although the element type of the vectors is __fp16,
15588	// the vectors shouldn't be treated as storage-only types. See the
15589	// discussion here: https://reviews.llvm.org/rG825235c140e7
15590	if (const VectorType *VT = Ty->getAs<VectorType>()) {
15591	if (VT->getVectorKind() == VectorKind::Neon)
15592	return false;
15593	return VT->getElementType().getCanonicalType() == Ctx.HalfTy;
15594	}
15595	return false;
15596	};
15597
15598	return HasVectorOfHalfType(E0) && (!E1 || HasVectorOfHalfType(E1));
15599	}
15600
15601	/// CreateBuiltinBinOp - Creates a new built-in binary operation with
15602	/// operator @p Opc at location @c TokLoc. This routine only supports
15603	/// built-in operations; ActOnBinOp handles overloaded operators.
15604	ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc,
15605	BinaryOperatorKind Opc,
15606	Expr *LHSExpr, Expr *RHSExpr) {
15607	if (getLangOpts().CPlusPlus11 && isa<InitListExpr>(Val: RHSExpr)) {
15608	// The syntax only allows initializer lists on the RHS of assignment,
15609	// so we don't need to worry about accepting invalid code for
15610	// non-assignment operators.
15611	// C++11 5.17p9:
15612	// The meaning of x = {v} [...] is that of x = T(v) [...]. The meaning
15613	// of x = {} is x = T().
15614	InitializationKind Kind = InitializationKind::CreateDirectList(
15615	RHSExpr->getBeginLoc(), RHSExpr->getBeginLoc(), RHSExpr->getEndLoc());
15616	InitializedEntity Entity =
15617	InitializedEntity::InitializeTemporary(Type: LHSExpr->getType());
15618	InitializationSequence InitSeq(*this, Entity, Kind, RHSExpr);
15619	ExprResult Init = InitSeq.Perform(S&: *this, Entity, Kind, Args: RHSExpr);
15620	if (Init.isInvalid())
15621	return Init;
15622	RHSExpr = Init.get();
15623	}
15624
15625	ExprResult LHS = LHSExpr, RHS = RHSExpr;
15626	QualType ResultTy; // Result type of the binary operator.
15627	// The following two variables are used for compound assignment operators
15628	QualType CompLHSTy; // Type of LHS after promotions for computation
15629	QualType CompResultTy; // Type of computation result
15630	ExprValueKind VK = VK_PRValue;
15631	ExprObjectKind OK = OK_Ordinary;
15632	bool ConvertHalfVec = false;
15633
15634	std::tie(args&: LHS, args&: RHS) = CorrectDelayedTyposInBinOp(S&: *this, Opc, LHSExpr, RHSExpr);
15635	if (!LHS.isUsable() || !RHS.isUsable())
15636	return ExprError();
15637
15638	if (getLangOpts().OpenCL) {
15639	QualType LHSTy = LHSExpr->getType();
15640	QualType RHSTy = RHSExpr->getType();
15641	// OpenCLC v2.0 s6.13.11.1 allows atomic variables to be initialized by
15642	// the ATOMIC_VAR_INIT macro.
15643	if (LHSTy->isAtomicType() || RHSTy->isAtomicType()) {
15644	SourceRange SR(LHSExpr->getBeginLoc(), RHSExpr->getEndLoc());
15645	if (BO_Assign == Opc)
15646	Diag(OpLoc, diag::err_opencl_atomic_init) << 0 << SR;
15647	else
15648	ResultTy = InvalidOperands(Loc: OpLoc, LHS, RHS);
15649	return ExprError();
15650	}
15651
15652	// OpenCL special types - image, sampler, pipe, and blocks are to be used
15653	// only with a builtin functions and therefore should be disallowed here.
15654	if (LHSTy->isImageType() || RHSTy->isImageType() ||
15655	LHSTy->isSamplerT() || RHSTy->isSamplerT() ||
15656	LHSTy->isPipeType() || RHSTy->isPipeType() ||
15657	LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) {
15658	ResultTy = InvalidOperands(Loc: OpLoc, LHS, RHS);
15659	return ExprError();
15660	}
15661	}
15662
15663	checkTypeSupport(Ty: LHSExpr->getType(), Loc: OpLoc, /*ValueDecl*/ D: nullptr);
15664	checkTypeSupport(Ty: RHSExpr->getType(), Loc: OpLoc, /*ValueDecl*/ D: nullptr);
15665
15666	switch (Opc) {
15667	case BO_Assign:
15668	ResultTy = CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: QualType(), Opc);
15669	if (getLangOpts().CPlusPlus &&
15670	LHS.get()->getObjectKind() != OK_ObjCProperty) {
15671	VK = LHS.get()->getValueKind();
15672	OK = LHS.get()->getObjectKind();
15673	}
15674	if (!ResultTy.isNull()) {
15675	DiagnoseSelfAssignment(S&: *this, LHSExpr: LHS.get(), RHSExpr: RHS.get(), OpLoc, IsBuiltin: true);
15676	DiagnoseSelfMove(LHSExpr: LHS.get(), RHSExpr: RHS.get(), OpLoc);
15677
15678	// Avoid copying a block to the heap if the block is assigned to a local
15679	// auto variable that is declared in the same scope as the block. This
15680	// optimization is unsafe if the local variable is declared in an outer
15681	// scope. For example:
15682	//
15683	// BlockTy b;
15684	// {
15685	// b = ^{...};
15686	// }
15687	// // It is unsafe to invoke the block here if it wasn't copied to the
15688	// // heap.
15689	// b();
15690
15691	if (auto *BE = dyn_cast<BlockExpr>(Val: RHS.get()->IgnoreParens()))
15692	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: LHS.get()->IgnoreParens()))
15693	if (auto *VD = dyn_cast<VarDecl>(Val: DRE->getDecl()))
15694	if (VD->hasLocalStorage() && getCurScope()->isDeclScope(VD))
15695	BE->getBlockDecl()->setCanAvoidCopyToHeap();
15696
15697	if (LHS.get()->getType().hasNonTrivialToPrimitiveCopyCUnion())
15698	checkNonTrivialCUnion(QT: LHS.get()->getType(), Loc: LHS.get()->getExprLoc(),
15699	UseContext: NTCUC_Assignment, NonTrivialKind: NTCUK_Copy);
15700	}
15701	RecordModifiableNonNullParam(S&: *this, Exp: LHS.get());
15702	break;
15703	case BO_PtrMemD:
15704	case BO_PtrMemI:
15705	ResultTy = CheckPointerToMemberOperands(LHS, RHS, VK, OpLoc,
15706	isIndirect: Opc == BO_PtrMemI);
15707	break;
15708	case BO_Mul:
15709	case BO_Div:
15710	ConvertHalfVec = true;
15711	ResultTy = CheckMultiplyDivideOperands(LHS, RHS, Loc: OpLoc, IsCompAssign: false,
15712	IsDiv: Opc == BO_Div);
15713	break;
15714	case BO_Rem:
15715	ResultTy = CheckRemainderOperands(LHS, RHS, Loc: OpLoc);
15716	break;
15717	case BO_Add:
15718	ConvertHalfVec = true;
15719	ResultTy = CheckAdditionOperands(LHS, RHS, Loc: OpLoc, Opc);
15720	break;
15721	case BO_Sub:
15722	ConvertHalfVec = true;
15723	ResultTy = CheckSubtractionOperands(LHS, RHS, Loc: OpLoc);
15724	break;
15725	case BO_Shl:
15726	case BO_Shr:
15727	ResultTy = CheckShiftOperands(LHS, RHS, Loc: OpLoc, Opc);
15728	break;
15729	case BO_LE:
15730	case BO_LT:
15731	case BO_GE:
15732	case BO_GT:
15733	ConvertHalfVec = true;
15734	ResultTy = CheckCompareOperands(LHS, RHS, Loc: OpLoc, Opc);
15735	break;
15736	case BO_EQ:
15737	case BO_NE:
15738	ConvertHalfVec = true;
15739	ResultTy = CheckCompareOperands(LHS, RHS, Loc: OpLoc, Opc);
15740	break;
15741	case BO_Cmp:
15742	ConvertHalfVec = true;
15743	ResultTy = CheckCompareOperands(LHS, RHS, Loc: OpLoc, Opc);
15744	assert(ResultTy.isNull() || ResultTy->getAsCXXRecordDecl());
15745	break;
15746	case BO_And:
15747	checkObjCPointerIntrospection(S&: *this, L&: LHS, R&: RHS, OpLoc);
15748	[[fallthrough]];
15749	case BO_Xor:
15750	case BO_Or:
15751	ResultTy = CheckBitwiseOperands(LHS, RHS, Loc: OpLoc, Opc);
15752	break;
15753	case BO_LAnd:
15754	case BO_LOr:
15755	ConvertHalfVec = true;
15756	ResultTy = CheckLogicalOperands(LHS, RHS, Loc: OpLoc, Opc);
15757	break;
15758	case BO_MulAssign:
15759	case BO_DivAssign:
15760	ConvertHalfVec = true;
15761	CompResultTy = CheckMultiplyDivideOperands(LHS, RHS, Loc: OpLoc, IsCompAssign: true,
15762	IsDiv: Opc == BO_DivAssign);
15763	CompLHSTy = CompResultTy;
15764	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15765	ResultTy =
15766	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15767	break;
15768	case BO_RemAssign:
15769	CompResultTy = CheckRemainderOperands(LHS, RHS, Loc: OpLoc, IsCompAssign: true);
15770	CompLHSTy = CompResultTy;
15771	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15772	ResultTy =
15773	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15774	break;
15775	case BO_AddAssign:
15776	ConvertHalfVec = true;
15777	CompResultTy = CheckAdditionOperands(LHS, RHS, Loc: OpLoc, Opc, CompLHSTy: &CompLHSTy);
15778	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15779	ResultTy =
15780	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15781	break;
15782	case BO_SubAssign:
15783	ConvertHalfVec = true;
15784	CompResultTy = CheckSubtractionOperands(LHS, RHS, Loc: OpLoc, CompLHSTy: &CompLHSTy);
15785	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15786	ResultTy =
15787	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15788	break;
15789	case BO_ShlAssign:
15790	case BO_ShrAssign:
15791	CompResultTy = CheckShiftOperands(LHS, RHS, Loc: OpLoc, Opc, IsCompAssign: true);
15792	CompLHSTy = CompResultTy;
15793	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15794	ResultTy =
15795	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15796	break;
15797	case BO_AndAssign:
15798	case BO_OrAssign: // fallthrough
15799	DiagnoseSelfAssignment(S&: *this, LHSExpr: LHS.get(), RHSExpr: RHS.get(), OpLoc, IsBuiltin: true);
15800	[[fallthrough]];
15801	case BO_XorAssign:
15802	CompResultTy = CheckBitwiseOperands(LHS, RHS, Loc: OpLoc, Opc);
15803	CompLHSTy = CompResultTy;
15804	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15805	ResultTy =
15806	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15807	break;
15808	case BO_Comma:
15809	ResultTy = CheckCommaOperands(S&: *this, LHS, RHS, Loc: OpLoc);
15810	if (getLangOpts().CPlusPlus && !RHS.isInvalid()) {
15811	VK = RHS.get()->getValueKind();
15812	OK = RHS.get()->getObjectKind();
15813	}
15814	break;
15815	}
15816	if (ResultTy.isNull() || LHS.isInvalid() || RHS.isInvalid())
15817	return ExprError();
15818
15819	// Some of the binary operations require promoting operands of half vector to
15820	// float vectors and truncating the result back to half vector. For now, we do
15821	// this only when HalfArgsAndReturn is set (that is, when the target is arm or
15822	// arm64).
15823	assert(
15824	(Opc == BO_Comma || isVector(RHS.get()->getType(), Context.HalfTy) ==
15825	isVector(LHS.get()->getType(), Context.HalfTy)) &&
15826	"both sides are half vectors or neither sides are");
15827	ConvertHalfVec =
15828	needsConversionOfHalfVec(OpRequiresConversion: ConvertHalfVec, Ctx&: Context, E0: LHS.get(), E1: RHS.get());
15829
15830	// Check for array bounds violations for both sides of the BinaryOperator
15831	CheckArrayAccess(E: LHS.get());
15832	CheckArrayAccess(E: RHS.get());
15833
15834	if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(Val: LHS.get()->IgnoreParenCasts())) {
15835	NamedDecl *ObjectSetClass = LookupSingleName(S: TUScope,
15836	Name: &Context.Idents.get(Name: "object_setClass"),
15837	Loc: SourceLocation(), NameKind: LookupOrdinaryName);
15838	if (ObjectSetClass && isa<ObjCIsaExpr>(Val: LHS.get())) {
15839	SourceLocation RHSLocEnd = getLocForEndOfToken(Loc: RHS.get()->getEndLoc());
15840	Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign)
15841	<< FixItHint::CreateInsertion(LHS.get()->getBeginLoc(),
15842	"object_setClass(")
15843	<< FixItHint::CreateReplacement(SourceRange(OISA->getOpLoc(), OpLoc),
15844	",")
15845	<< FixItHint::CreateInsertion(RHSLocEnd, ")");
15846	}
15847	else
15848	Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign);
15849	}
15850	else if (const ObjCIvarRefExpr *OIRE =
15851	dyn_cast<ObjCIvarRefExpr>(Val: LHS.get()->IgnoreParenCasts()))
15852	DiagnoseDirectIsaAccess(S&: *this, OIRE, AssignLoc: OpLoc, RHS: RHS.get());
15853
15854	// Opc is not a compound assignment if CompResultTy is null.
15855	if (CompResultTy.isNull()) {
15856	if (ConvertHalfVec)
15857	return convertHalfVecBinOp(S&: *this, LHS, RHS, Opc, ResultTy, VK, OK, IsCompAssign: false,
15858	OpLoc, FPFeatures: CurFPFeatureOverrides());
15859	return BinaryOperator::Create(C: Context, lhs: LHS.get(), rhs: RHS.get(), opc: Opc, ResTy: ResultTy,
15860	VK, OK, opLoc: OpLoc, FPFeatures: CurFPFeatureOverrides());
15861	}
15862
15863	// Handle compound assignments.
15864	if (getLangOpts().CPlusPlus && LHS.get()->getObjectKind() !=
15865	OK_ObjCProperty) {
15866	VK = VK_LValue;
15867	OK = LHS.get()->getObjectKind();
15868	}
15869
15870	// The LHS is not converted to the result type for fixed-point compound
15871	// assignment as the common type is computed on demand. Reset the CompLHSTy
15872	// to the LHS type we would have gotten after unary conversions.
15873	if (CompResultTy->isFixedPointType())
15874	CompLHSTy = UsualUnaryConversions(E: LHS.get()).get()->getType();
15875
15876	if (ConvertHalfVec)
15877	return convertHalfVecBinOp(S&: *this, LHS, RHS, Opc, ResultTy, VK, OK, IsCompAssign: true,
15878	OpLoc, FPFeatures: CurFPFeatureOverrides());
15879
15880	return CompoundAssignOperator::Create(
15881	C: Context, lhs: LHS.get(), rhs: RHS.get(), opc: Opc, ResTy: ResultTy, VK, OK, opLoc: OpLoc,
15882	FPFeatures: CurFPFeatureOverrides(), CompLHSType: CompLHSTy, CompResultType: CompResultTy);
15883	}
15884
15885	/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison
15886	/// operators are mixed in a way that suggests that the programmer forgot that
15887	/// comparison operators have higher precedence. The most typical example of
15888	/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1".
15889	static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc,
15890	SourceLocation OpLoc, Expr *LHSExpr,
15891	Expr *RHSExpr) {
15892	BinaryOperator *LHSBO = dyn_cast<BinaryOperator>(Val: LHSExpr);
15893	BinaryOperator *RHSBO = dyn_cast<BinaryOperator>(Val: RHSExpr);
15894
15895	// Check that one of the sides is a comparison operator and the other isn't.
15896	bool isLeftComp = LHSBO && LHSBO->isComparisonOp();
15897	bool isRightComp = RHSBO && RHSBO->isComparisonOp();
15898	if (isLeftComp == isRightComp)
15899	return;
15900
15901	// Bitwise operations are sometimes used as eager logical ops.
15902	// Don't diagnose this.
15903	bool isLeftBitwise = LHSBO && LHSBO->isBitwiseOp();
15904	bool isRightBitwise = RHSBO && RHSBO->isBitwiseOp();
15905	if (isLeftBitwise || isRightBitwise)
15906	return;
15907
15908	SourceRange DiagRange = isLeftComp
15909	? SourceRange(LHSExpr->getBeginLoc(), OpLoc)
15910	: SourceRange(OpLoc, RHSExpr->getEndLoc());
15911	StringRef OpStr = isLeftComp ? LHSBO->getOpcodeStr() : RHSBO->getOpcodeStr();
15912	SourceRange ParensRange =
15913	isLeftComp
15914	? SourceRange(LHSBO->getRHS()->getBeginLoc(), RHSExpr->getEndLoc())
15915	: SourceRange(LHSExpr->getBeginLoc(), RHSBO->getLHS()->getEndLoc());
15916
15917	Self.Diag(OpLoc, diag::warn_precedence_bitwise_rel)
15918	<< DiagRange << BinaryOperator::getOpcodeStr(Opc) << OpStr;
15919	SuggestParentheses(Self, OpLoc,
15920	Self.PDiag(diag::note_precedence_silence) << OpStr,
15921	(isLeftComp ? LHSExpr : RHSExpr)->getSourceRange());
15922	SuggestParentheses(Self, OpLoc,
15923	Self.PDiag(diag::note_precedence_bitwise_first)
15924	<< BinaryOperator::getOpcodeStr(Opc),
15925	ParensRange);
15926	}
15927
15928	/// It accepts a '&&' expr that is inside a '||' one.
15929	/// Emit a diagnostic together with a fixit hint that wraps the '&&' expression
15930	/// in parentheses.
15931	static void
15932	EmitDiagnosticForLogicalAndInLogicalOr(Sema &Self, SourceLocation OpLoc,
15933	BinaryOperator *Bop) {
15934	assert(Bop->getOpcode() == BO_LAnd);
15935	Self.Diag(Bop->getOperatorLoc(), diag::warn_logical_and_in_logical_or)
15936	<< Bop->getSourceRange() << OpLoc;
15937	SuggestParentheses(Self, Bop->getOperatorLoc(),
15938	Self.PDiag(diag::note_precedence_silence)
15939	<< Bop->getOpcodeStr(),
15940	Bop->getSourceRange());
15941	}
15942
15943	/// Look for '&&' in the left hand of a '||' expr.
15944	static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc,
15945	Expr *LHSExpr, Expr *RHSExpr) {
15946	if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(Val: LHSExpr)) {
15947	if (Bop->getOpcode() == BO_LAnd) {
15948	// If it's "string_literal && a || b" don't warn since the precedence
15949	// doesn't matter.
15950	if (!isa<StringLiteral>(Val: Bop->getLHS()->IgnoreParenImpCasts()))
15951	return EmitDiagnosticForLogicalAndInLogicalOr(Self&: S, OpLoc, Bop);
15952	} else if (Bop->getOpcode() == BO_LOr) {
15953	if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Val: Bop->getRHS())) {
15954	// If it's "a || b && string_literal || c" we didn't warn earlier for
15955	// "a || b && string_literal", but warn now.
15956	if (RBop->getOpcode() == BO_LAnd &&
15957	isa<StringLiteral>(Val: RBop->getRHS()->IgnoreParenImpCasts()))
15958	return EmitDiagnosticForLogicalAndInLogicalOr(Self&: S, OpLoc, Bop: RBop);
15959	}
15960	}
15961	}
15962	}
15963
15964	/// Look for '&&' in the right hand of a '||' expr.
15965	static void DiagnoseLogicalAndInLogicalOrRHS(Sema &S, SourceLocation OpLoc,
15966	Expr *LHSExpr, Expr *RHSExpr) {
15967	if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(Val: RHSExpr)) {
15968	if (Bop->getOpcode() == BO_LAnd) {
15969	// If it's "a || b && string_literal" don't warn since the precedence
15970	// doesn't matter.
15971	if (!isa<StringLiteral>(Val: Bop->getRHS()->IgnoreParenImpCasts()))
15972	return EmitDiagnosticForLogicalAndInLogicalOr(Self&: S, OpLoc, Bop);
15973	}
15974	}
15975	}
15976
15977	/// Look for bitwise op in the left or right hand of a bitwise op with
15978	/// lower precedence and emit a diagnostic together with a fixit hint that wraps
15979	/// the '&' expression in parentheses.
15980	static void DiagnoseBitwiseOpInBitwiseOp(Sema &S, BinaryOperatorKind Opc,
15981	SourceLocation OpLoc, Expr *SubExpr) {
15982	if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(Val: SubExpr)) {
15983	if (Bop->isBitwiseOp() && Bop->getOpcode() < Opc) {
15984	S.Diag(Bop->getOperatorLoc(), diag::warn_bitwise_op_in_bitwise_op)
15985	<< Bop->getOpcodeStr() << BinaryOperator::getOpcodeStr(Opc)
15986	<< Bop->getSourceRange() << OpLoc;
15987	SuggestParentheses(S, Bop->getOperatorLoc(),
15988	S.PDiag(diag::note_precedence_silence)
15989	<< Bop->getOpcodeStr(),
15990	Bop->getSourceRange());
15991	}
15992	}
15993	}
15994
15995	static void DiagnoseAdditionInShift(Sema &S, SourceLocation OpLoc,
15996	Expr *SubExpr, StringRef Shift) {
15997	if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(Val: SubExpr)) {
15998	if (Bop->getOpcode() == BO_Add || Bop->getOpcode() == BO_Sub) {
15999	StringRef Op = Bop->getOpcodeStr();
16000	S.Diag(Bop->getOperatorLoc(), diag::warn_addition_in_bitshift)
16001	<< Bop->getSourceRange() << OpLoc << Shift << Op;
16002	SuggestParentheses(S, Bop->getOperatorLoc(),
16003	S.PDiag(diag::note_precedence_silence) << Op,
16004	Bop->getSourceRange());
16005	}
16006	}
16007	}
16008
16009	static void DiagnoseShiftCompare(Sema &S, SourceLocation OpLoc,
16010	Expr *LHSExpr, Expr *RHSExpr) {
16011	CXXOperatorCallExpr *OCE = dyn_cast<CXXOperatorCallExpr>(Val: LHSExpr);
16012	if (!OCE)
16013	return;
16014
16015	FunctionDecl *FD = OCE->getDirectCallee();
16016	if (!FD || !FD->isOverloadedOperator())
16017	return;
16018
16019	OverloadedOperatorKind Kind = FD->getOverloadedOperator();
16020	if (Kind != OO_LessLess && Kind != OO_GreaterGreater)
16021	return;
16022
16023	S.Diag(OpLoc, diag::warn_overloaded_shift_in_comparison)
16024	<< LHSExpr->getSourceRange() << RHSExpr->getSourceRange()
16025	<< (Kind == OO_LessLess);
16026	SuggestParentheses(S, OCE->getOperatorLoc(),
16027	S.PDiag(diag::note_precedence_silence)
16028	<< (Kind == OO_LessLess ? "<<" : ">>"),
16029	OCE->getSourceRange());
16030	SuggestParentheses(
16031	S, OpLoc, S.PDiag(diag::note_evaluate_comparison_first),
16032	SourceRange(OCE->getArg(1)->getBeginLoc(), RHSExpr->getEndLoc()));
16033	}
16034
16035	/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky
16036	/// precedence.
16037	static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc,
16038	SourceLocation OpLoc, Expr *LHSExpr,
16039	Expr *RHSExpr){
16040	// Diagnose "arg1 'bitwise' arg2 'eq' arg3".
16041	if (BinaryOperator::isBitwiseOp(Opc))
16042	DiagnoseBitwisePrecedence(Self, Opc, OpLoc, LHSExpr, RHSExpr);
16043
16044	// Diagnose "arg1 & arg2 | arg3"
16045	if ((Opc == BO_Or || Opc == BO_Xor) &&
16046	!OpLoc.isMacroID()/* Don't warn in macros. */) {
16047	DiagnoseBitwiseOpInBitwiseOp(S&: Self, Opc, OpLoc, SubExpr: LHSExpr);
16048	DiagnoseBitwiseOpInBitwiseOp(S&: Self, Opc, OpLoc, SubExpr: RHSExpr);
16049	}
16050
16051	// Warn about arg1 || arg2 && arg3, as GCC 4.3+ does.
16052	// We don't warn for 'assert(a || b && "bad")' since this is safe.
16053	if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) {
16054	DiagnoseLogicalAndInLogicalOrLHS(S&: Self, OpLoc, LHSExpr, RHSExpr);
16055	DiagnoseLogicalAndInLogicalOrRHS(S&: Self, OpLoc, LHSExpr, RHSExpr);
16056	}
16057
16058	if ((Opc == BO_Shl && LHSExpr->getType()->isIntegralType(Ctx: Self.getASTContext()))
16059	|| Opc == BO_Shr) {
16060	StringRef Shift = BinaryOperator::getOpcodeStr(Op: Opc);
16061	DiagnoseAdditionInShift(S&: Self, OpLoc, SubExpr: LHSExpr, Shift);
16062	DiagnoseAdditionInShift(S&: Self, OpLoc, SubExpr: RHSExpr, Shift);
16063	}
16064
16065	// Warn on overloaded shift operators and comparisons, such as:
16066	// cout << 5 == 4;
16067	if (BinaryOperator::isComparisonOp(Opc))
16068	DiagnoseShiftCompare(S&: Self, OpLoc, LHSExpr, RHSExpr);
16069	}
16070
16071	// Binary Operators. 'Tok' is the token for the operator.
16072	ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc,
16073	tok::TokenKind Kind,
16074	Expr *LHSExpr, Expr *RHSExpr) {
16075	BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind);
16076	assert(LHSExpr && "ActOnBinOp(): missing left expression");
16077	assert(RHSExpr && "ActOnBinOp(): missing right expression");
16078
16079	// Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0"
16080	DiagnoseBinOpPrecedence(Self&: *this, Opc, OpLoc: TokLoc, LHSExpr, RHSExpr);
16081
16082	return BuildBinOp(S, OpLoc: TokLoc, Opc, LHSExpr, RHSExpr);
16083	}
16084
16085	void Sema::LookupBinOp(Scope *S, SourceLocation OpLoc, BinaryOperatorKind Opc,
16086	UnresolvedSetImpl &Functions) {
16087	OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc);
16088	if (OverOp != OO_None && OverOp != OO_Equal)
16089	LookupOverloadedOperatorName(Op: OverOp, S, Functions);
16090
16091	// In C++20 onwards, we may have a second operator to look up.
16092	if (getLangOpts().CPlusPlus20) {
16093	if (OverloadedOperatorKind ExtraOp = getRewrittenOverloadedOperator(Kind: OverOp))
16094	LookupOverloadedOperatorName(Op: ExtraOp, S, Functions);
16095	}
16096	}
16097
16098	/// Build an overloaded binary operator expression in the given scope.
16099	static ExprResult BuildOverloadedBinOp(Sema &S, Scope *Sc, SourceLocation OpLoc,
16100	BinaryOperatorKind Opc,
16101	Expr *LHS, Expr *RHS) {
16102	switch (Opc) {
16103	case BO_Assign:
16104	// In the non-overloaded case, we warn about self-assignment (x = x) for
16105	// both simple assignment and certain compound assignments where algebra
16106	// tells us the operation yields a constant result. When the operator is
16107	// overloaded, we can't do the latter because we don't want to assume that
16108	// those algebraic identities still apply; for example, a path-building
16109	// library might use operator/= to append paths. But it's still reasonable
16110	// to assume that simple assignment is just moving/copying values around
16111	// and so self-assignment is likely a bug.
16112	DiagnoseSelfAssignment(S, LHSExpr: LHS, RHSExpr: RHS, OpLoc, IsBuiltin: false);
16113	[[fallthrough]];
16114	case BO_DivAssign:
16115	case BO_RemAssign:
16116	case BO_SubAssign:
16117	case BO_AndAssign:
16118	case BO_OrAssign:
16119	case BO_XorAssign:
16120	CheckIdentityFieldAssignment(LHSExpr: LHS, RHSExpr: RHS, Loc: OpLoc, Sema&: S);
16121	break;
16122	default:
16123	break;
16124	}
16125
16126	// Find all of the overloaded operators visible from this point.
16127	UnresolvedSet<16> Functions;
16128	S.LookupBinOp(S: Sc, OpLoc, Opc, Functions);
16129
16130	// Build the (potentially-overloaded, potentially-dependent)
16131	// binary operation.
16132	return S.CreateOverloadedBinOp(OpLoc, Opc, Fns: Functions, LHS, RHS);
16133	}
16134
16135	ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc,
16136	BinaryOperatorKind Opc,
16137	Expr *LHSExpr, Expr *RHSExpr) {
16138	ExprResult LHS, RHS;
16139	std::tie(args&: LHS, args&: RHS) = CorrectDelayedTyposInBinOp(S&: *this, Opc, LHSExpr, RHSExpr);
16140	if (!LHS.isUsable() || !RHS.isUsable())
16141	return ExprError();
16142	LHSExpr = LHS.get();
16143	RHSExpr = RHS.get();
16144
16145	// We want to end up calling one of checkPseudoObjectAssignment
16146	// (if the LHS is a pseudo-object), BuildOverloadedBinOp (if
16147	// both expressions are overloadable or either is type-dependent),
16148	// or CreateBuiltinBinOp (in any other case). We also want to get
16149	// any placeholder types out of the way.
16150
16151	// Handle pseudo-objects in the LHS.
16152	if (const BuiltinType *pty = LHSExpr->getType()->getAsPlaceholderType()) {
16153	// Assignments with a pseudo-object l-value need special analysis.
16154	if (pty->getKind() == BuiltinType::PseudoObject &&
16155	BinaryOperator::isAssignmentOp(Opc))
16156	return checkPseudoObjectAssignment(S, OpLoc, Opcode: Opc, LHS: LHSExpr, RHS: RHSExpr);
16157
16158	// Don't resolve overloads if the other type is overloadable.
16159	if (getLangOpts().CPlusPlus && pty->getKind() == BuiltinType::Overload) {
16160	// We can't actually test that if we still have a placeholder,
16161	// though. Fortunately, none of the exceptions we see in that
16162	// code below are valid when the LHS is an overload set. Note
16163	// that an overload set can be dependently-typed, but it never
16164	// instantiates to having an overloadable type.
16165	ExprResult resolvedRHS = CheckPlaceholderExpr(E: RHSExpr);
16166	if (resolvedRHS.isInvalid()) return ExprError();
16167	RHSExpr = resolvedRHS.get();
16168
16169	if (RHSExpr->isTypeDependent() ||
16170	RHSExpr->getType()->isOverloadableType())
16171	return BuildOverloadedBinOp(S&: *this, Sc: S, OpLoc, Opc, LHS: LHSExpr, RHS: RHSExpr);
16172	}
16173
16174	// If we're instantiating "a.x < b" or "A::x < b" and 'x' names a function
16175	// template, diagnose the missing 'template' keyword instead of diagnosing
16176	// an invalid use of a bound member function.
16177	//
16178	// Note that "A::x < b" might be valid if 'b' has an overloadable type due
16179	// to C++1z [over.over]/1.4, but we already checked for that case above.
16180	if (Opc == BO_LT && inTemplateInstantiation() &&
16181	(pty->getKind() == BuiltinType::BoundMember ||
16182	pty->getKind() == BuiltinType::Overload)) {
16183	auto *OE = dyn_cast<OverloadExpr>(Val: LHSExpr);
16184	if (OE && !OE->hasTemplateKeyword() && !OE->hasExplicitTemplateArgs() &&
16185	llvm::any_of(Range: OE->decls(), P: [](NamedDecl *ND) {
16186	return isa<FunctionTemplateDecl>(Val: ND);
16187	})) {
16188	Diag(OE->getQualifier() ? OE->getQualifierLoc().getBeginLoc()
16189	: OE->getNameLoc(),
16190	diag::err_template_kw_missing)
16191	<< OE->getName().getAsString() << "";
16192	return ExprError();
16193	}
16194	}
16195
16196	ExprResult LHS = CheckPlaceholderExpr(E: LHSExpr);
16197	if (LHS.isInvalid()) return ExprError();
16198	LHSExpr = LHS.get();
16199	}
16200
16201	// Handle pseudo-objects in the RHS.
16202	if (const BuiltinType *pty = RHSExpr->getType()->getAsPlaceholderType()) {
16203	// An overload in the RHS can potentially be resolved by the type
16204	// being assigned to.
16205	if (Opc == BO_Assign && pty->getKind() == BuiltinType::Overload) {
16206	if (getLangOpts().CPlusPlus &&
16207	(LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent() ||
16208	LHSExpr->getType()->isOverloadableType()))
16209	return BuildOverloadedBinOp(S&: *this, Sc: S, OpLoc, Opc, LHS: LHSExpr, RHS: RHSExpr);
16210
16211	return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr);
16212	}
16213
16214	// Don't resolve overloads if the other type is overloadable.
16215	if (getLangOpts().CPlusPlus && pty->getKind() == BuiltinType::Overload &&
16216	LHSExpr->getType()->isOverloadableType())
16217	return BuildOverloadedBinOp(S&: *this, Sc: S, OpLoc, Opc, LHS: LHSExpr, RHS: RHSExpr);
16218
16219	ExprResult resolvedRHS = CheckPlaceholderExpr(E: RHSExpr);
16220	if (!resolvedRHS.isUsable()) return ExprError();
16221	RHSExpr = resolvedRHS.get();
16222	}
16223
16224	if (getLangOpts().CPlusPlus) {
16225	// If either expression is type-dependent, always build an
16226	// overloaded op.
16227	if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent())
16228	return BuildOverloadedBinOp(S&: *this, Sc: S, OpLoc, Opc, LHS: LHSExpr, RHS: RHSExpr);
16229
16230	// Otherwise, build an overloaded op if either expression has an
16231	// overloadable type.
16232	if (LHSExpr->getType()->isOverloadableType() ||
16233	RHSExpr->getType()->isOverloadableType())
16234	return BuildOverloadedBinOp(S&: *this, Sc: S, OpLoc, Opc, LHS: LHSExpr, RHS: RHSExpr);
16235	}
16236
16237	if (getLangOpts().RecoveryAST &&
16238	(LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent())) {
16239	assert(!getLangOpts().CPlusPlus);
16240	assert((LHSExpr->containsErrors() || RHSExpr->containsErrors()) &&
16241	"Should only occur in error-recovery path.");
16242	if (BinaryOperator::isCompoundAssignmentOp(Opc))
16243	// C [6.15.16] p3:
16244	// An assignment expression has the value of the left operand after the
16245	// assignment, but is not an lvalue.
16246	return CompoundAssignOperator::Create(
16247	C: Context, lhs: LHSExpr, rhs: RHSExpr, opc: Opc,
16248	ResTy: LHSExpr->getType().getUnqualifiedType(), VK: VK_PRValue, OK: OK_Ordinary,
16249	opLoc: OpLoc, FPFeatures: CurFPFeatureOverrides());
16250	QualType ResultType;
16251	switch (Opc) {
16252	case BO_Assign:
16253	ResultType = LHSExpr->getType().getUnqualifiedType();
16254	break;
16255	case BO_LT:
16256	case BO_GT:
16257	case BO_LE:
16258	case BO_GE:
16259	case BO_EQ:
16260	case BO_NE:
16261	case BO_LAnd:
16262	case BO_LOr:
16263	// These operators have a fixed result type regardless of operands.
16264	ResultType = Context.IntTy;
16265	break;
16266	case BO_Comma:
16267	ResultType = RHSExpr->getType();
16268	break;
16269	default:
16270	ResultType = Context.DependentTy;
16271	break;
16272	}
16273	return BinaryOperator::Create(C: Context, lhs: LHSExpr, rhs: RHSExpr, opc: Opc, ResTy: ResultType,
16274	VK: VK_PRValue, OK: OK_Ordinary, opLoc: OpLoc,
16275	FPFeatures: CurFPFeatureOverrides());
16276	}
16277
16278	// Build a built-in binary operation.
16279	return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr);
16280	}
16281
16282	static bool isOverflowingIntegerType(ASTContext &Ctx, QualType T) {
16283	if (T.isNull() || T->isDependentType())
16284	return false;
16285
16286	if (!Ctx.isPromotableIntegerType(T))
16287	return true;
16288
16289	return Ctx.getIntWidth(T) >= Ctx.getIntWidth(T: Ctx.IntTy);
16290	}
16291
16292	ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc,
16293	UnaryOperatorKind Opc, Expr *InputExpr,
16294	bool IsAfterAmp) {
16295	ExprResult Input = InputExpr;
16296	ExprValueKind VK = VK_PRValue;
16297	ExprObjectKind OK = OK_Ordinary;
16298	QualType resultType;
16299	bool CanOverflow = false;
16300
16301	bool ConvertHalfVec = false;
16302	if (getLangOpts().OpenCL) {
16303	QualType Ty = InputExpr->getType();
16304	// The only legal unary operation for atomics is '&'.
16305	if ((Opc != UO_AddrOf && Ty->isAtomicType()) ||
16306	// OpenCL special types - image, sampler, pipe, and blocks are to be used
16307	// only with a builtin functions and therefore should be disallowed here.
16308	(Ty->isImageType() || Ty->isSamplerT() || Ty->isPipeType()
16309	|| Ty->isBlockPointerType())) {
16310	return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
16311	<< InputExpr->getType()
16312	<< Input.get()->getSourceRange());
16313	}
16314	}
16315
16316	if (getLangOpts().HLSL && OpLoc.isValid()) {
16317	if (Opc == UO_AddrOf)
16318	return ExprError(Diag(OpLoc, diag::err_hlsl_operator_unsupported) << 0);
16319	if (Opc == UO_Deref)
16320	return ExprError(Diag(OpLoc, diag::err_hlsl_operator_unsupported) << 1);
16321	}
16322
16323	switch (Opc) {
16324	case UO_PreInc:
16325	case UO_PreDec:
16326	case UO_PostInc:
16327	case UO_PostDec:
16328	resultType = CheckIncrementDecrementOperand(S&: *this, Op: Input.get(), VK, OK,
16329	OpLoc,
16330	IsInc: Opc == UO_PreInc ||
16331	Opc == UO_PostInc,
16332	IsPrefix: Opc == UO_PreInc ||
16333	Opc == UO_PreDec);
16334	CanOverflow = isOverflowingIntegerType(Ctx&: Context, T: resultType);
16335	break;
16336	case UO_AddrOf:
16337	resultType = CheckAddressOfOperand(OrigOp&: Input, OpLoc);
16338	CheckAddressOfNoDeref(E: InputExpr);
16339	RecordModifiableNonNullParam(S&: *this, Exp: InputExpr);
16340	break;
16341	case UO_Deref: {
16342	Input = DefaultFunctionArrayLvalueConversion(E: Input.get());
16343	if (Input.isInvalid()) return ExprError();
16344	resultType =
16345	CheckIndirectionOperand(S&: *this, Op: Input.get(), VK, OpLoc, IsAfterAmp);
16346	break;
16347	}
16348	case UO_Plus:
16349	case UO_Minus:
16350	CanOverflow = Opc == UO_Minus &&
16351	isOverflowingIntegerType(Ctx&: Context, T: Input.get()->getType());
16352	Input = UsualUnaryConversions(E: Input.get());
16353	if (Input.isInvalid()) return ExprError();
16354	// Unary plus and minus require promoting an operand of half vector to a
16355	// float vector and truncating the result back to a half vector. For now, we
16356	// do this only when HalfArgsAndReturns is set (that is, when the target is
16357	// arm or arm64).
16358	ConvertHalfVec = needsConversionOfHalfVec(OpRequiresConversion: true, Ctx&: Context, E0: Input.get());
16359
16360	// If the operand is a half vector, promote it to a float vector.
16361	if (ConvertHalfVec)
16362	Input = convertVector(Input.get(), Context.FloatTy, *this);
16363	resultType = Input.get()->getType();
16364	if (resultType->isDependentType())
16365	break;
16366	if (resultType->isArithmeticType()) // C99 6.5.3.3p1
16367	break;
16368	else if (resultType->isVectorType() &&
16369	// The z vector extensions don't allow + or - with bool vectors.
16370	(!Context.getLangOpts().ZVector ||
16371	resultType->castAs<VectorType>()->getVectorKind() !=
16372	VectorKind::AltiVecBool))
16373	break;
16374	else if (resultType->isSveVLSBuiltinType()) // SVE vectors allow + and -
16375	break;
16376	else if (getLangOpts().CPlusPlus && // C++ [expr.unary.op]p6
16377	Opc == UO_Plus &&
16378	resultType->isPointerType())
16379	break;
16380
16381	return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
16382	<< resultType << Input.get()->getSourceRange());
16383
16384	case UO_Not: // bitwise complement
16385	Input = UsualUnaryConversions(E: Input.get());
16386	if (Input.isInvalid())
16387	return ExprError();
16388	resultType = Input.get()->getType();
16389	if (resultType->isDependentType())
16390	break;
16391	// C99 6.5.3.3p1. We allow complex int and float as a GCC extension.
16392	if (resultType->isComplexType() || resultType->isComplexIntegerType())
16393	// C99 does not support '~' for complex conjugation.
16394	Diag(OpLoc, diag::ext_integer_complement_complex)
16395	<< resultType << Input.get()->getSourceRange();
16396	else if (resultType->hasIntegerRepresentation())
16397	break;
16398	else if (resultType->isExtVectorType() && Context.getLangOpts().OpenCL) {
16399	// OpenCL v1.1 s6.3.f: The bitwise operator not (~) does not operate
16400	// on vector float types.
16401	QualType T = resultType->castAs<ExtVectorType>()->getElementType();
16402	if (!T->isIntegerType())
16403	return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
16404	<< resultType << Input.get()->getSourceRange());
16405	} else {
16406	return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
16407	<< resultType << Input.get()->getSourceRange());
16408	}
16409	break;
16410
16411	case UO_LNot: // logical negation
16412	// Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5).
16413	Input = DefaultFunctionArrayLvalueConversion(E: Input.get());
16414	if (Input.isInvalid()) return ExprError();
16415	resultType = Input.get()->getType();
16416
16417	// Though we still have to promote half FP to float...
16418	if (resultType->isHalfType() && !Context.getLangOpts().NativeHalfType) {
16419	Input = ImpCastExprToType(E: Input.get(), Type: Context.FloatTy, CK: CK_FloatingCast).get();
16420	resultType = Context.FloatTy;
16421	}
16422
16423	// WebAsembly tables can't be used in unary expressions.
16424	if (resultType->isPointerType() &&
16425	resultType->getPointeeType().isWebAssemblyReferenceType()) {
16426	return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
16427	<< resultType << Input.get()->getSourceRange());
16428	}
16429
16430	if (resultType->isDependentType())
16431	break;
16432	if (resultType->isScalarType() && !isScopedEnumerationType(T: resultType)) {
16433	// C99 6.5.3.3p1: ok, fallthrough;
16434	if (Context.getLangOpts().CPlusPlus) {
16435	// C++03 [expr.unary.op]p8, C++0x [expr.unary.op]p9:
16436	// operand contextually converted to bool.
16437	Input = ImpCastExprToType(E: Input.get(), Type: Context.BoolTy,
16438	CK: ScalarTypeToBooleanCastKind(ScalarTy: resultType));
16439	} else if (Context.getLangOpts().OpenCL &&
16440	Context.getLangOpts().OpenCLVersion < 120) {
16441	// OpenCL v1.1 6.3.h: The logical operator not (!) does not
16442	// operate on scalar float types.
16443	if (!resultType->isIntegerType() && !resultType->isPointerType())
16444	return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
16445	<< resultType << Input.get()->getSourceRange());
16446	}
16447	} else if (resultType->isExtVectorType()) {
16448	if (Context.getLangOpts().OpenCL &&
16449	Context.getLangOpts().getOpenCLCompatibleVersion() < 120) {
16450	// OpenCL v1.1 6.3.h: The logical operator not (!) does not
16451	// operate on vector float types.
16452	QualType T = resultType->castAs<ExtVectorType>()->getElementType();
16453	if (!T->isIntegerType())
16454	return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
16455	<< resultType << Input.get()->getSourceRange());
16456	}
16457	// Vector logical not returns the signed variant of the operand type.
16458	resultType = GetSignedVectorType(V: resultType);
16459	break;
16460	} else if (Context.getLangOpts().CPlusPlus && resultType->isVectorType()) {
16461	const VectorType *VTy = resultType->castAs<VectorType>();
16462	if (VTy->getVectorKind() != VectorKind::Generic)
16463	return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
16464	<< resultType << Input.get()->getSourceRange());
16465
16466	// Vector logical not returns the signed variant of the operand type.
16467	resultType = GetSignedVectorType(V: resultType);
16468	break;
16469	} else {
16470	return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
16471	<< resultType << Input.get()->getSourceRange());
16472	}
16473
16474	// LNot always has type int. C99 6.5.3.3p5.
16475	// In C++, it's bool. C++ 5.3.1p8
16476	resultType = Context.getLogicalOperationType();
16477	break;
16478	case UO_Real:
16479	case UO_Imag:
16480	resultType = CheckRealImagOperand(S&: *this, V&: Input, Loc: OpLoc, IsReal: Opc == UO_Real);
16481	// _Real maps ordinary l-values into ordinary l-values. _Imag maps ordinary
16482	// complex l-values to ordinary l-values and all other values to r-values.
16483	if (Input.isInvalid()) return ExprError();
16484	if (Opc == UO_Real || Input.get()->getType()->isAnyComplexType()) {
16485	if (Input.get()->isGLValue() &&
16486	Input.get()->getObjectKind() == OK_Ordinary)
16487	VK = Input.get()->getValueKind();
16488	} else if (!getLangOpts().CPlusPlus) {
16489	// In C, a volatile scalar is read by __imag. In C++, it is not.
16490	Input = DefaultLvalueConversion(E: Input.get());
16491	}
16492	break;
16493	case UO_Extension:
16494	resultType = Input.get()->getType();
16495	VK = Input.get()->getValueKind();
16496	OK = Input.get()->getObjectKind();
16497	break;
16498	case UO_Coawait:
16499	// It's unnecessary to represent the pass-through operator co_await in the
16500	// AST; just return the input expression instead.
16501	assert(!Input.get()->getType()->isDependentType() &&
16502	"the co_await expression must be non-dependant before "
16503	"building operator co_await");
16504	return Input;
16505	}
16506	if (resultType.isNull() || Input.isInvalid())
16507	return ExprError();
16508
16509	// Check for array bounds violations in the operand of the UnaryOperator,
16510	// except for the '*' and '&' operators that have to be handled specially
16511	// by CheckArrayAccess (as there are special cases like &array[arraysize]
16512	// that are explicitly defined as valid by the standard).
16513	if (Opc != UO_AddrOf && Opc != UO_Deref)
16514	CheckArrayAccess(E: Input.get());
16515
16516	auto *UO =
16517	UnaryOperator::Create(C: Context, input: Input.get(), opc: Opc, type: resultType, VK, OK,
16518	l: OpLoc, CanOverflow, FPFeatures: CurFPFeatureOverrides());
16519
16520	if (Opc == UO_Deref && UO->getType()->hasAttr(attr::NoDeref) &&
16521	!isa<ArrayType>(UO->getType().getDesugaredType(Context)) &&
16522	!isUnevaluatedContext())
16523	ExprEvalContexts.back().PossibleDerefs.insert(UO);
16524
16525	// Convert the result back to a half vector.
16526	if (ConvertHalfVec)
16527	return convertVector(UO, Context.HalfTy, *this);
16528	return UO;
16529	}
16530
16531	/// Determine whether the given expression is a qualified member
16532	/// access expression, of a form that could be turned into a pointer to member
16533	/// with the address-of operator.
16534	bool Sema::isQualifiedMemberAccess(Expr *E) {
16535	if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: E)) {
16536	if (!DRE->getQualifier())
16537	return false;
16538
16539	ValueDecl *VD = DRE->getDecl();
16540	if (!VD->isCXXClassMember())
16541	return false;
16542
16543	if (isa<FieldDecl>(Val: VD) || isa<IndirectFieldDecl>(Val: VD))
16544	return true;
16545	if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Val: VD))
16546	return Method->isImplicitObjectMemberFunction();
16547
16548	return false;
16549	}
16550
16551	if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Val: E)) {
16552	if (!ULE->getQualifier())
16553	return false;
16554
16555	for (NamedDecl *D : ULE->decls()) {
16556	if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
16557	if (Method->isImplicitObjectMemberFunction())
16558	return true;
16559	} else {
16560	// Overload set does not contain methods.
16561	break;
16562	}
16563	}
16564
16565	return false;
16566	}
16567
16568	return false;
16569	}
16570
16571	ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc,
16572	UnaryOperatorKind Opc, Expr *Input,
16573	bool IsAfterAmp) {
16574	// First things first: handle placeholders so that the
16575	// overloaded-operator check considers the right type.
16576	if (const BuiltinType *pty = Input->getType()->getAsPlaceholderType()) {
16577	// Increment and decrement of pseudo-object references.
16578	if (pty->getKind() == BuiltinType::PseudoObject &&
16579	UnaryOperator::isIncrementDecrementOp(Op: Opc))
16580	return checkPseudoObjectIncDec(S, OpLoc, Opcode: Opc, Op: Input);
16581
16582	// extension is always a builtin operator.
16583	if (Opc == UO_Extension)
16584	return CreateBuiltinUnaryOp(OpLoc, Opc, InputExpr: Input);
16585
16586	// & gets special logic for several kinds of placeholder.
16587	// The builtin code knows what to do.
16588	if (Opc == UO_AddrOf &&
16589	(pty->getKind() == BuiltinType::Overload ||
16590	pty->getKind() == BuiltinType::UnknownAny ||
16591	pty->getKind() == BuiltinType::BoundMember))
16592	return CreateBuiltinUnaryOp(OpLoc, Opc, InputExpr: Input);
16593
16594	// Anything else needs to be handled now.
16595	ExprResult Result = CheckPlaceholderExpr(E: Input);
16596	if (Result.isInvalid()) return ExprError();
16597	Input = Result.get();
16598	}
16599
16600	if (getLangOpts().CPlusPlus && Input->getType()->isOverloadableType() &&
16601	UnaryOperator::getOverloadedOperator(Opc) != OO_None &&
16602	!(Opc == UO_AddrOf && isQualifiedMemberAccess(E: Input))) {
16603	// Find all of the overloaded operators visible from this point.
16604	UnresolvedSet<16> Functions;
16605	OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc);
16606	if (S && OverOp != OO_None)
16607	LookupOverloadedOperatorName(Op: OverOp, S, Functions);
16608
16609	return CreateOverloadedUnaryOp(OpLoc, Opc, Fns: Functions, input: Input);
16610	}
16611
16612	return CreateBuiltinUnaryOp(OpLoc, Opc, InputExpr: Input, IsAfterAmp);
16613	}
16614
16615	// Unary Operators. 'Tok' is the token for the operator.
16616	ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, tok::TokenKind Op,
16617	Expr *Input, bool IsAfterAmp) {
16618	return BuildUnaryOp(S, OpLoc, Opc: ConvertTokenKindToUnaryOpcode(Kind: Op), Input,
16619	IsAfterAmp);
16620	}
16621
16622	/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo".
16623	ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc,
16624	LabelDecl *TheDecl) {
16625	TheDecl->markUsed(Context);
16626	// Create the AST node. The address of a label always has type 'void*'.
16627	auto *Res = new (Context) AddrLabelExpr(
16628	OpLoc, LabLoc, TheDecl, Context.getPointerType(Context.VoidTy));
16629
16630	if (getCurFunction())
16631	getCurFunction()->AddrLabels.push_back(Elt: Res);
16632
16633	return Res;
16634	}
16635
16636	void Sema::ActOnStartStmtExpr() {
16637	PushExpressionEvaluationContext(NewContext: ExprEvalContexts.back().Context);
16638	// Make sure we diagnose jumping into a statement expression.
16639	setFunctionHasBranchProtectedScope();
16640	}
16641
16642	void Sema::ActOnStmtExprError() {
16643	// Note that function is also called by TreeTransform when leaving a
16644	// StmtExpr scope without rebuilding anything.
16645
16646	DiscardCleanupsInEvaluationContext();
16647	PopExpressionEvaluationContext();
16648	}
16649
16650	ExprResult Sema::ActOnStmtExpr(Scope *S, SourceLocation LPLoc, Stmt *SubStmt,
16651	SourceLocation RPLoc) {
16652	return BuildStmtExpr(LPLoc, SubStmt, RPLoc, TemplateDepth: getTemplateDepth(S));
16653	}
16654
16655	ExprResult Sema::BuildStmtExpr(SourceLocation LPLoc, Stmt *SubStmt,
16656	SourceLocation RPLoc, unsigned TemplateDepth) {
16657	assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!");
16658	CompoundStmt *Compound = cast<CompoundStmt>(Val: SubStmt);
16659
16660	if (hasAnyUnrecoverableErrorsInThisFunction())
16661	DiscardCleanupsInEvaluationContext();
16662	assert(!Cleanup.exprNeedsCleanups() &&
16663	"cleanups within StmtExpr not correctly bound!");
16664	PopExpressionEvaluationContext();
16665
16666	// FIXME: there are a variety of strange constraints to enforce here, for
16667	// example, it is not possible to goto into a stmt expression apparently.
16668	// More semantic analysis is needed.
16669
16670	// If there are sub-stmts in the compound stmt, take the type of the last one
16671	// as the type of the stmtexpr.
16672	QualType Ty = Context.VoidTy;
16673	bool StmtExprMayBindToTemp = false;
16674	if (!Compound->body_empty()) {
16675	// For GCC compatibility we get the last Stmt excluding trailing NullStmts.
16676	if (const auto *LastStmt =
16677	dyn_cast<ValueStmt>(Val: Compound->getStmtExprResult())) {
16678	if (const Expr *Value = LastStmt->getExprStmt()) {
16679	StmtExprMayBindToTemp = true;
16680	Ty = Value->getType();
16681	}
16682	}
16683	}
16684
16685	// FIXME: Check that expression type is complete/non-abstract; statement
16686	// expressions are not lvalues.
16687	Expr *ResStmtExpr =
16688	new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc, TemplateDepth);
16689	if (StmtExprMayBindToTemp)
16690	return MaybeBindToTemporary(E: ResStmtExpr);
16691	return ResStmtExpr;
16692	}
16693
16694	ExprResult Sema::ActOnStmtExprResult(ExprResult ER) {
16695	if (ER.isInvalid())
16696	return ExprError();
16697
16698	// Do function/array conversion on the last expression, but not
16699	// lvalue-to-rvalue. However, initialize an unqualified type.
16700	ER = DefaultFunctionArrayConversion(E: ER.get());
16701	if (ER.isInvalid())
16702	return ExprError();
16703	Expr *E = ER.get();
16704
16705	if (E->isTypeDependent())
16706	return E;
16707
16708	// In ARC, if the final expression ends in a consume, splice
16709	// the consume out and bind it later. In the alternate case
16710	// (when dealing with a retainable type), the result
16711	// initialization will create a produce. In both cases the
16712	// result will be +1, and we'll need to balance that out with
16713	// a bind.
16714	auto *Cast = dyn_cast<ImplicitCastExpr>(Val: E);
16715	if (Cast && Cast->getCastKind() == CK_ARCConsumeObject)
16716	return Cast->getSubExpr();
16717
16718	// FIXME: Provide a better location for the initialization.
16719	return PerformCopyInitialization(
16720	Entity: InitializedEntity::InitializeStmtExprResult(
16721	ReturnLoc: E->getBeginLoc(), Type: E->getType().getUnqualifiedType()),
16722	EqualLoc: SourceLocation(), Init: E);
16723	}
16724
16725	ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc,
16726	TypeSourceInfo *TInfo,
16727	ArrayRef<OffsetOfComponent> Components,
16728	SourceLocation RParenLoc) {
16729	QualType ArgTy = TInfo->getType();
16730	bool Dependent = ArgTy->isDependentType();
16731	SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange();
16732
16733	// We must have at least one component that refers to the type, and the first
16734	// one is known to be a field designator. Verify that the ArgTy represents
16735	// a struct/union/class.
16736	if (!Dependent && !ArgTy->isRecordType())
16737	return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type)
16738	<< ArgTy << TypeRange);
16739
16740	// Type must be complete per C99 7.17p3 because a declaring a variable
16741	// with an incomplete type would be ill-formed.
16742	if (!Dependent
16743	&& RequireCompleteType(BuiltinLoc, ArgTy,
16744	diag::err_offsetof_incomplete_type, TypeRange))
16745	return ExprError();
16746
16747	bool DidWarnAboutNonPOD = false;
16748	QualType CurrentType = ArgTy;
16749	SmallVector<OffsetOfNode, 4> Comps;
16750	SmallVector<Expr*, 4> Exprs;
16751	for (const OffsetOfComponent &OC : Components) {
16752	if (OC.isBrackets) {
16753	// Offset of an array sub-field. TODO: Should we allow vector elements?
16754	if (!CurrentType->isDependentType()) {
16755	const ArrayType *AT = Context.getAsArrayType(T: CurrentType);
16756	if(!AT)
16757	return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type)
16758	<< CurrentType);
16759	CurrentType = AT->getElementType();
16760	} else
16761	CurrentType = Context.DependentTy;
16762
16763	ExprResult IdxRval = DefaultLvalueConversion(E: static_cast<Expr*>(OC.U.E));
16764	if (IdxRval.isInvalid())
16765	return ExprError();
16766	Expr *Idx = IdxRval.get();
16767
16768	// The expression must be an integral expression.
16769	// FIXME: An integral constant expression?
16770	if (!Idx->isTypeDependent() && !Idx->isValueDependent() &&
16771	!Idx->getType()->isIntegerType())
16772	return ExprError(
16773	Diag(Idx->getBeginLoc(), diag::err_typecheck_subscript_not_integer)
16774	<< Idx->getSourceRange());
16775
16776	// Record this array index.
16777	Comps.push_back(Elt: OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd));
16778	Exprs.push_back(Elt: Idx);
16779	continue;
16780	}
16781
16782	// Offset of a field.
16783	if (CurrentType->isDependentType()) {
16784	// We have the offset of a field, but we can't look into the dependent
16785	// type. Just record the identifier of the field.
16786	Comps.push_back(Elt: OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd));
16787	CurrentType = Context.DependentTy;
16788	continue;
16789	}
16790
16791	// We need to have a complete type to look into.
16792	if (RequireCompleteType(OC.LocStart, CurrentType,
16793	diag::err_offsetof_incomplete_type))
16794	return ExprError();
16795
16796	// Look for the designated field.
16797	const RecordType *RC = CurrentType->getAs<RecordType>();
16798	if (!RC)
16799	return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type)
16800	<< CurrentType);
16801	RecordDecl *RD = RC->getDecl();
16802
16803	// C++ [lib.support.types]p5:
16804	// The macro offsetof accepts a restricted set of type arguments in this
16805	// International Standard. type shall be a POD structure or a POD union
16806	// (clause 9).
16807	// C++11 [support.types]p4:
16808	// If type is not a standard-layout class (Clause 9), the results are
16809	// undefined.
16810	if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(Val: RD)) {
16811	bool IsSafe = LangOpts.CPlusPlus11? CRD->isStandardLayout() : CRD->isPOD();
16812	unsigned DiagID =
16813	LangOpts.CPlusPlus11? diag::ext_offsetof_non_standardlayout_type
16814	: diag::ext_offsetof_non_pod_type;
16815
16816	if (!IsSafe && !DidWarnAboutNonPOD && !isUnevaluatedContext()) {
16817	Diag(Loc: BuiltinLoc, DiagID)
16818	<< SourceRange(Components[0].LocStart, OC.LocEnd) << CurrentType;
16819	DidWarnAboutNonPOD = true;
16820	}
16821	}
16822
16823	// Look for the field.
16824	LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName);
16825	LookupQualifiedName(R, RD);
16826	FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>();
16827	IndirectFieldDecl *IndirectMemberDecl = nullptr;
16828	if (!MemberDecl) {
16829	if ((IndirectMemberDecl = R.getAsSingle<IndirectFieldDecl>()))
16830	MemberDecl = IndirectMemberDecl->getAnonField();
16831	}
16832
16833	if (!MemberDecl) {
16834	// Lookup could be ambiguous when looking up a placeholder variable
16835	// __builtin_offsetof(S, _).
16836	// In that case we would already have emitted a diagnostic
16837	if (!R.isAmbiguous())
16838	Diag(BuiltinLoc, diag::err_no_member)
16839	<< OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd);
16840	return ExprError();
16841	}
16842
16843	// C99 7.17p3:
16844	// (If the specified member is a bit-field, the behavior is undefined.)
16845	//
16846	// We diagnose this as an error.
16847	if (MemberDecl->isBitField()) {
16848	Diag(OC.LocEnd, diag::err_offsetof_bitfield)
16849	<< MemberDecl->getDeclName()
16850	<< SourceRange(BuiltinLoc, RParenLoc);
16851	Diag(MemberDecl->getLocation(), diag::note_bitfield_decl);
16852	return ExprError();
16853	}
16854
16855	RecordDecl *Parent = MemberDecl->getParent();
16856	if (IndirectMemberDecl)
16857	Parent = cast<RecordDecl>(IndirectMemberDecl->getDeclContext());
16858
16859	// If the member was found in a base class, introduce OffsetOfNodes for
16860	// the base class indirections.
16861	CXXBasePaths Paths;
16862	if (IsDerivedFrom(Loc: OC.LocStart, Derived: CurrentType, Base: Context.getTypeDeclType(Parent),
16863	Paths)) {
16864	if (Paths.getDetectedVirtual()) {
16865	Diag(OC.LocEnd, diag::err_offsetof_field_of_virtual_base)
16866	<< MemberDecl->getDeclName()
16867	<< SourceRange(BuiltinLoc, RParenLoc);
16868	return ExprError();
16869	}
16870
16871	CXXBasePath &Path = Paths.front();
16872	for (const CXXBasePathElement &B : Path)
16873	Comps.push_back(Elt: OffsetOfNode(B.Base));
16874	}
16875
16876	if (IndirectMemberDecl) {
16877	for (auto *FI : IndirectMemberDecl->chain()) {
16878	assert(isa<FieldDecl>(FI));
16879	Comps.push_back(Elt: OffsetOfNode(OC.LocStart,
16880	cast<FieldDecl>(Val: FI), OC.LocEnd));
16881	}
16882	} else
16883	Comps.push_back(Elt: OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd));
16884
16885	CurrentType = MemberDecl->getType().getNonReferenceType();
16886	}
16887
16888	return OffsetOfExpr::Create(C: Context, type: Context.getSizeType(), OperatorLoc: BuiltinLoc, tsi: TInfo,
16889	comps: Comps, exprs: Exprs, RParenLoc);
16890	}
16891
16892	ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
16893	SourceLocation BuiltinLoc,
16894	SourceLocation TypeLoc,
16895	ParsedType ParsedArgTy,
16896	ArrayRef<OffsetOfComponent> Components,
16897	SourceLocation RParenLoc) {
16898
16899	TypeSourceInfo *ArgTInfo;
16900	QualType ArgTy = GetTypeFromParser(Ty: ParsedArgTy, TInfo: &ArgTInfo);
16901	if (ArgTy.isNull())
16902	return ExprError();
16903
16904	if (!ArgTInfo)
16905	ArgTInfo = Context.getTrivialTypeSourceInfo(T: ArgTy, Loc: TypeLoc);
16906
16907	return BuildBuiltinOffsetOf(BuiltinLoc, TInfo: ArgTInfo, Components, RParenLoc);
16908	}
16909
16910
16911	ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc,
16912	Expr *CondExpr,
16913	Expr *LHSExpr, Expr *RHSExpr,
16914	SourceLocation RPLoc) {
16915	assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)");
16916
16917	ExprValueKind VK = VK_PRValue;
16918	ExprObjectKind OK = OK_Ordinary;
16919	QualType resType;
16920	bool CondIsTrue = false;
16921	if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) {
16922	resType = Context.DependentTy;
16923	} else {
16924	// The conditional expression is required to be a constant expression.
16925	llvm::APSInt condEval(32);
16926	ExprResult CondICE = VerifyIntegerConstantExpression(
16927	CondExpr, &condEval, diag::err_typecheck_choose_expr_requires_constant);
16928	if (CondICE.isInvalid())
16929	return ExprError();
16930	CondExpr = CondICE.get();
16931	CondIsTrue = condEval.getZExtValue();
16932
16933	// If the condition is > zero, then the AST type is the same as the LHSExpr.
16934	Expr *ActiveExpr = CondIsTrue ? LHSExpr : RHSExpr;
16935
16936	resType = ActiveExpr->getType();
16937	VK = ActiveExpr->getValueKind();
16938	OK = ActiveExpr->getObjectKind();
16939	}
16940
16941	return new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr,
16942	resType, VK, OK, RPLoc, CondIsTrue);
16943	}
16944
16945	//===----------------------------------------------------------------------===//
16946	// Clang Extensions.
16947	//===----------------------------------------------------------------------===//
16948
16949	/// ActOnBlockStart - This callback is invoked when a block literal is started.
16950	void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope) {
16951	BlockDecl *Block = BlockDecl::Create(C&: Context, DC: CurContext, L: CaretLoc);
16952
16953	if (LangOpts.CPlusPlus) {
16954	MangleNumberingContext *MCtx;
16955	Decl *ManglingContextDecl;
16956	std::tie(args&: MCtx, args&: ManglingContextDecl) =
16957	getCurrentMangleNumberContext(DC: Block->getDeclContext());
16958	if (MCtx) {
16959	unsigned ManglingNumber = MCtx->getManglingNumber(BD: Block);
16960	Block->setBlockMangling(Number: ManglingNumber, Ctx: ManglingContextDecl);
16961	}
16962	}
16963
16964	PushBlockScope(BlockScope: CurScope, Block);
16965	CurContext->addDecl(Block);
16966	if (CurScope)
16967	PushDeclContext(CurScope, Block);
16968	else
16969	CurContext = Block;
16970
16971	getCurBlock()->HasImplicitReturnType = true;
16972
16973	// Enter a new evaluation context to insulate the block from any
16974	// cleanups from the enclosing full-expression.
16975	PushExpressionEvaluationContext(
16976	NewContext: ExpressionEvaluationContext::PotentiallyEvaluated);
16977	}
16978
16979	void Sema::ActOnBlockArguments(SourceLocation CaretLoc, Declarator &ParamInfo,
16980	Scope *CurScope) {
16981	assert(ParamInfo.getIdentifier() == nullptr &&
16982	"block-id should have no identifier!");
16983	assert(ParamInfo.getContext() == DeclaratorContext::BlockLiteral);
16984	BlockScopeInfo *CurBlock = getCurBlock();
16985
16986	TypeSourceInfo *Sig = GetTypeForDeclarator(D&: ParamInfo);
16987	QualType T = Sig->getType();
16988
16989	// FIXME: We should allow unexpanded parameter packs here, but that would,
16990	// in turn, make the block expression contain unexpanded parameter packs.
16991	if (DiagnoseUnexpandedParameterPack(Loc: CaretLoc, T: Sig, UPPC: UPPC_Block)) {
16992	// Drop the parameters.
16993	FunctionProtoType::ExtProtoInfo EPI;
16994	EPI.HasTrailingReturn = false;
16995	EPI.TypeQuals.addConst();
16996	T = Context.getFunctionType(ResultTy: Context.DependentTy, Args: std::nullopt, EPI);
16997	Sig = Context.getTrivialTypeSourceInfo(T);
16998	}
16999
17000	// GetTypeForDeclarator always produces a function type for a block
17001	// literal signature. Furthermore, it is always a FunctionProtoType
17002	// unless the function was written with a typedef.
17003	assert(T->isFunctionType() &&
17004	"GetTypeForDeclarator made a non-function block signature");
17005
17006	// Look for an explicit signature in that function type.
17007	FunctionProtoTypeLoc ExplicitSignature;
17008
17009	if ((ExplicitSignature = Sig->getTypeLoc()
17010	.getAsAdjusted<FunctionProtoTypeLoc>())) {
17011
17012	// Check whether that explicit signature was synthesized by
17013	// GetTypeForDeclarator. If so, don't save that as part of the
17014	// written signature.
17015	if (ExplicitSignature.getLocalRangeBegin() ==
17016	ExplicitSignature.getLocalRangeEnd()) {
17017	// This would be much cheaper if we stored TypeLocs instead of
17018	// TypeSourceInfos.
17019	TypeLoc Result = ExplicitSignature.getReturnLoc();
17020	unsigned Size = Result.getFullDataSize();
17021	Sig = Context.CreateTypeSourceInfo(T: Result.getType(), Size);
17022	Sig->getTypeLoc().initializeFullCopy(Other: Result, Size);
17023
17024	ExplicitSignature = FunctionProtoTypeLoc();
17025	}
17026	}
17027
17028	CurBlock->TheDecl->setSignatureAsWritten(Sig);
17029	CurBlock->FunctionType = T;
17030
17031	const auto *Fn = T->castAs<FunctionType>();
17032	QualType RetTy = Fn->getReturnType();
17033	bool isVariadic =
17034	(isa<FunctionProtoType>(Val: Fn) && cast<FunctionProtoType>(Val: Fn)->isVariadic());
17035
17036	CurBlock->TheDecl->setIsVariadic(isVariadic);
17037
17038	// Context.DependentTy is used as a placeholder for a missing block
17039	// return type. TODO: what should we do with declarators like:
17040	// ^ * { ... }
17041	// If the answer is "apply template argument deduction"....
17042	if (RetTy != Context.DependentTy) {
17043	CurBlock->ReturnType = RetTy;
17044	CurBlock->TheDecl->setBlockMissingReturnType(false);
17045	CurBlock->HasImplicitReturnType = false;
17046	}
17047
17048	// Push block parameters from the declarator if we had them.
17049	SmallVector<ParmVarDecl*, 8> Params;
17050	if (ExplicitSignature) {
17051	for (unsigned I = 0, E = ExplicitSignature.getNumParams(); I != E; ++I) {
17052	ParmVarDecl *Param = ExplicitSignature.getParam(I);
17053	if (Param->getIdentifier() == nullptr && !Param->isImplicit() &&
17054	!Param->isInvalidDecl() && !getLangOpts().CPlusPlus) {
17055	// Diagnose this as an extension in C17 and earlier.
17056	if (!getLangOpts().C23)
17057	Diag(Param->getLocation(), diag::ext_parameter_name_omitted_c23);
17058	}
17059	Params.push_back(Elt: Param);
17060	}
17061
17062	// Fake up parameter variables if we have a typedef, like
17063	// ^ fntype { ... }
17064	} else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) {
17065	for (const auto &I : Fn->param_types()) {
17066	ParmVarDecl *Param = BuildParmVarDeclForTypedef(
17067	CurBlock->TheDecl, ParamInfo.getBeginLoc(), I);
17068	Params.push_back(Elt: Param);
17069	}
17070	}
17071
17072	// Set the parameters on the block decl.
17073	if (!Params.empty()) {
17074	CurBlock->TheDecl->setParams(Params);
17075	CheckParmsForFunctionDef(Parameters: CurBlock->TheDecl->parameters(),
17076	/*CheckParameterNames=*/false);
17077	}
17078
17079	// Finally we can process decl attributes.
17080	ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo);
17081
17082	// Put the parameter variables in scope.
17083	for (auto *AI : CurBlock->TheDecl->parameters()) {
17084	AI->setOwningFunction(CurBlock->TheDecl);
17085
17086	// If this has an identifier, add it to the scope stack.
17087	if (AI->getIdentifier()) {
17088	CheckShadow(CurBlock->TheScope, AI);
17089
17090	PushOnScopeChains(AI, CurBlock->TheScope);
17091	}
17092
17093	if (AI->isInvalidDecl())
17094	CurBlock->TheDecl->setInvalidDecl();
17095	}
17096	}
17097
17098	/// ActOnBlockError - If there is an error parsing a block, this callback
17099	/// is invoked to pop the information about the block from the action impl.
17100	void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) {
17101	// Leave the expression-evaluation context.
17102	DiscardCleanupsInEvaluationContext();
17103	PopExpressionEvaluationContext();
17104
17105	// Pop off CurBlock, handle nested blocks.
17106	PopDeclContext();
17107	PopFunctionScopeInfo();
17108	}
17109
17110	/// ActOnBlockStmtExpr - This is called when the body of a block statement
17111	/// literal was successfully completed. ^(int x){...}
17112	ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc,
17113	Stmt *Body, Scope *CurScope) {
17114	// If blocks are disabled, emit an error.
17115	if (!LangOpts.Blocks)
17116	Diag(CaretLoc, diag::err_blocks_disable) << LangOpts.OpenCL;
17117
17118	// Leave the expression-evaluation context.
17119	if (hasAnyUnrecoverableErrorsInThisFunction())
17120	DiscardCleanupsInEvaluationContext();
17121	assert(!Cleanup.exprNeedsCleanups() &&
17122	"cleanups within block not correctly bound!");
17123	PopExpressionEvaluationContext();
17124
17125	BlockScopeInfo *BSI = cast<BlockScopeInfo>(Val: FunctionScopes.back());
17126	BlockDecl *BD = BSI->TheDecl;
17127
17128	if (BSI->HasImplicitReturnType)
17129	deduceClosureReturnType(*BSI);
17130
17131	QualType RetTy = Context.VoidTy;
17132	if (!BSI->ReturnType.isNull())
17133	RetTy = BSI->ReturnType;
17134
17135	bool NoReturn = BD->hasAttr<NoReturnAttr>();
17136	QualType BlockTy;
17137
17138	// If the user wrote a function type in some form, try to use that.
17139	if (!BSI->FunctionType.isNull()) {
17140	const FunctionType *FTy = BSI->FunctionType->castAs<FunctionType>();
17141
17142	FunctionType::ExtInfo Ext = FTy->getExtInfo();
17143	if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(noReturn: true);
17144
17145	// Turn protoless block types into nullary block types.
17146	if (isa<FunctionNoProtoType>(Val: FTy)) {
17147	FunctionProtoType::ExtProtoInfo EPI;
17148	EPI.ExtInfo = Ext;
17149	BlockTy = Context.getFunctionType(ResultTy: RetTy, Args: std::nullopt, EPI);
17150
17151	// Otherwise, if we don't need to change anything about the function type,
17152	// preserve its sugar structure.
17153	} else if (FTy->getReturnType() == RetTy &&
17154	(!NoReturn || FTy->getNoReturnAttr())) {
17155	BlockTy = BSI->FunctionType;
17156
17157	// Otherwise, make the minimal modifications to the function type.
17158	} else {
17159	const FunctionProtoType *FPT = cast<FunctionProtoType>(Val: FTy);
17160	FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
17161	EPI.TypeQuals = Qualifiers();
17162	EPI.ExtInfo = Ext;
17163	BlockTy = Context.getFunctionType(ResultTy: RetTy, Args: FPT->getParamTypes(), EPI);
17164	}
17165
17166	// If we don't have a function type, just build one from nothing.
17167	} else {
17168	FunctionProtoType::ExtProtoInfo EPI;
17169	EPI.ExtInfo = FunctionType::ExtInfo().withNoReturn(noReturn: NoReturn);
17170	BlockTy = Context.getFunctionType(ResultTy: RetTy, Args: std::nullopt, EPI);
17171	}
17172
17173	DiagnoseUnusedParameters(Parameters: BD->parameters());
17174	BlockTy = Context.getBlockPointerType(T: BlockTy);
17175
17176	// If needed, diagnose invalid gotos and switches in the block.
17177	if (getCurFunction()->NeedsScopeChecking() &&
17178	!PP.isCodeCompletionEnabled())
17179	DiagnoseInvalidJumps(cast<CompoundStmt>(Val: Body));
17180
17181	BD->setBody(cast<CompoundStmt>(Val: Body));
17182
17183	if (Body && getCurFunction()->HasPotentialAvailabilityViolations)
17184	DiagnoseUnguardedAvailabilityViolations(BD);
17185
17186	// Try to apply the named return value optimization. We have to check again
17187	// if we can do this, though, because blocks keep return statements around
17188	// to deduce an implicit return type.
17189	if (getLangOpts().CPlusPlus && RetTy->isRecordType() &&
17190	!BD->isDependentContext())
17191	computeNRVO(Body, BSI);
17192
17193	if (RetTy.hasNonTrivialToPrimitiveDestructCUnion() ||
17194	RetTy.hasNonTrivialToPrimitiveCopyCUnion())
17195	checkNonTrivialCUnion(QT: RetTy, Loc: BD->getCaretLocation(), UseContext: NTCUC_FunctionReturn,
17196	NonTrivialKind: NTCUK_Destruct|NTCUK_Copy);
17197
17198	PopDeclContext();
17199
17200	// Set the captured variables on the block.
17201	SmallVector<BlockDecl::Capture, 4> Captures;
17202	for (Capture &Cap : BSI->Captures) {
17203	if (Cap.isInvalid() || Cap.isThisCapture())
17204	continue;
17205	// Cap.getVariable() is always a VarDecl because
17206	// blocks cannot capture structured bindings or other ValueDecl kinds.
17207	auto *Var = cast<VarDecl>(Val: Cap.getVariable());
17208	Expr *CopyExpr = nullptr;
17209	if (getLangOpts().CPlusPlus && Cap.isCopyCapture()) {
17210	if (const RecordType *Record =
17211	Cap.getCaptureType()->getAs<RecordType>()) {
17212	// The capture logic needs the destructor, so make sure we mark it.
17213	// Usually this is unnecessary because most local variables have
17214	// their destructors marked at declaration time, but parameters are
17215	// an exception because it's technically only the call site that
17216	// actually requires the destructor.
17217	if (isa<ParmVarDecl>(Val: Var))
17218	FinalizeVarWithDestructor(VD: Var, DeclInitType: Record);
17219
17220	// Enter a separate potentially-evaluated context while building block
17221	// initializers to isolate their cleanups from those of the block
17222	// itself.
17223	// FIXME: Is this appropriate even when the block itself occurs in an
17224	// unevaluated operand?
17225	EnterExpressionEvaluationContext EvalContext(
17226	*this, ExpressionEvaluationContext::PotentiallyEvaluated);
17227
17228	SourceLocation Loc = Cap.getLocation();
17229
17230	ExprResult Result = BuildDeclarationNameExpr(
17231	CXXScopeSpec(), DeclarationNameInfo(Var->getDeclName(), Loc), Var);
17232
17233	// According to the blocks spec, the capture of a variable from
17234	// the stack requires a const copy constructor. This is not true
17235	// of the copy/move done to move a __block variable to the heap.
17236	if (!Result.isInvalid() &&
17237	!Result.get()->getType().isConstQualified()) {
17238	Result = ImpCastExprToType(E: Result.get(),
17239	Type: Result.get()->getType().withConst(),
17240	CK: CK_NoOp, VK: VK_LValue);
17241	}
17242
17243	if (!Result.isInvalid()) {
17244	Result = PerformCopyInitialization(
17245	Entity: InitializedEntity::InitializeBlock(BlockVarLoc: Var->getLocation(),
17246	Type: Cap.getCaptureType()),
17247	EqualLoc: Loc, Init: Result.get());
17248	}
17249
17250	// Build a full-expression copy expression if initialization
17251	// succeeded and used a non-trivial constructor. Recover from
17252	// errors by pretending that the copy isn't necessary.
17253	if (!Result.isInvalid() &&
17254	!cast<CXXConstructExpr>(Val: Result.get())->getConstructor()
17255	->isTrivial()) {
17256	Result = MaybeCreateExprWithCleanups(SubExpr: Result);
17257	CopyExpr = Result.get();
17258	}
17259	}
17260	}
17261
17262	BlockDecl::Capture NewCap(Var, Cap.isBlockCapture(), Cap.isNested(),
17263	CopyExpr);
17264	Captures.push_back(Elt: NewCap);
17265	}
17266	BD->setCaptures(Context, Captures, CapturesCXXThis: BSI->CXXThisCaptureIndex != 0);
17267
17268	// Pop the block scope now but keep it alive to the end of this function.
17269	AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
17270	PoppedFunctionScopePtr ScopeRAII = PopFunctionScopeInfo(&WP, BD, BlockTy);
17271
17272	BlockExpr *Result = new (Context) BlockExpr(BD, BlockTy);
17273
17274	// If the block isn't obviously global, i.e. it captures anything at
17275	// all, then we need to do a few things in the surrounding context:
17276	if (Result->getBlockDecl()->hasCaptures()) {
17277	// First, this expression has a new cleanup object.
17278	ExprCleanupObjects.push_back(Elt: Result->getBlockDecl());
17279	Cleanup.setExprNeedsCleanups(true);
17280
17281	// It also gets a branch-protected scope if any of the captured
17282	// variables needs destruction.
17283	for (const auto &CI : Result->getBlockDecl()->captures()) {
17284	const VarDecl *var = CI.getVariable();
17285	if (var->getType().isDestructedType() != QualType::DK_none) {
17286	setFunctionHasBranchProtectedScope();
17287	break;
17288	}
17289	}
17290	}
17291
17292	if (getCurFunction())
17293	getCurFunction()->addBlock(BD);
17294
17295	if (BD->isInvalidDecl())
17296	return CreateRecoveryExpr(Begin: Result->getBeginLoc(), End: Result->getEndLoc(),
17297	SubExprs: {Result}, T: Result->getType());
17298	return Result;
17299	}
17300
17301	ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, Expr *E, ParsedType Ty,
17302	SourceLocation RPLoc) {
17303	TypeSourceInfo *TInfo;
17304	GetTypeFromParser(Ty, TInfo: &TInfo);
17305	return BuildVAArgExpr(BuiltinLoc, E, TInfo, RPLoc);
17306	}
17307
17308	ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc,
17309	Expr *E, TypeSourceInfo *TInfo,
17310	SourceLocation RPLoc) {
17311	Expr *OrigExpr = E;
17312	bool IsMS = false;
17313
17314	// CUDA device code does not support varargs.
17315	if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) {
17316	if (const FunctionDecl *F = dyn_cast<FunctionDecl>(Val: CurContext)) {
17317	CUDAFunctionTarget T = IdentifyCUDATarget(D: F);
17318	if (T == CFT_Global || T == CFT_Device || T == CFT_HostDevice)
17319	return ExprError(Diag(E->getBeginLoc(), diag::err_va_arg_in_device));
17320	}
17321	}
17322
17323	// NVPTX does not support va_arg expression.
17324	if (getLangOpts().OpenMP && getLangOpts().OpenMPIsTargetDevice &&
17325	Context.getTargetInfo().getTriple().isNVPTX())
17326	targetDiag(E->getBeginLoc(), diag::err_va_arg_in_device);
17327
17328	// It might be a __builtin_ms_va_list. (But don't ever mark a va_arg()
17329	// as Microsoft ABI on an actual Microsoft platform, where
17330	// __builtin_ms_va_list and __builtin_va_list are the same.)
17331	if (!E->isTypeDependent() && Context.getTargetInfo().hasBuiltinMSVaList() &&
17332	Context.getTargetInfo().getBuiltinVaListKind() != TargetInfo::CharPtrBuiltinVaList) {
17333	QualType MSVaListType = Context.getBuiltinMSVaListType();
17334	if (Context.hasSameType(T1: MSVaListType, T2: E->getType())) {
17335	if (CheckForModifiableLvalue(E, Loc: BuiltinLoc, S&: *this))
17336	return ExprError();
17337	IsMS = true;
17338	}
17339	}
17340
17341	// Get the va_list type
17342	QualType VaListType = Context.getBuiltinVaListType();
17343	if (!IsMS) {
17344	if (VaListType->isArrayType()) {
17345	// Deal with implicit array decay; for example, on x86-64,
17346	// va_list is an array, but it's supposed to decay to
17347	// a pointer for va_arg.
17348	VaListType = Context.getArrayDecayedType(T: VaListType);
17349	// Make sure the input expression also decays appropriately.
17350	ExprResult Result = UsualUnaryConversions(E);
17351	if (Result.isInvalid())
17352	return ExprError();
17353	E = Result.get();
17354	} else if (VaListType->isRecordType() && getLangOpts().CPlusPlus) {
17355	// If va_list is a record type and we are compiling in C++ mode,
17356	// check the argument using reference binding.
17357	InitializedEntity Entity = InitializedEntity::InitializeParameter(
17358	Context, Type: Context.getLValueReferenceType(T: VaListType), Consumed: false);
17359	ExprResult Init = PerformCopyInitialization(Entity, EqualLoc: SourceLocation(), Init: E);
17360	if (Init.isInvalid())
17361	return ExprError();
17362	E = Init.getAs<Expr>();
17363	} else {
17364	// Otherwise, the va_list argument must be an l-value because
17365	// it is modified by va_arg.
17366	if (!E->isTypeDependent() &&
17367	CheckForModifiableLvalue(E, Loc: BuiltinLoc, S&: *this))
17368	return ExprError();
17369	}
17370	}
17371
17372	if (!IsMS && !E->isTypeDependent() &&
17373	!Context.hasSameType(VaListType, E->getType()))
17374	return ExprError(
17375	Diag(E->getBeginLoc(),
17376	diag::err_first_argument_to_va_arg_not_of_type_va_list)
17377	<< OrigExpr->getType() << E->getSourceRange());
17378
17379	if (!TInfo->getType()->isDependentType()) {
17380	if (RequireCompleteType(TInfo->getTypeLoc().getBeginLoc(), TInfo->getType(),
17381	diag::err_second_parameter_to_va_arg_incomplete,
17382	TInfo->getTypeLoc()))
17383	return ExprError();
17384
17385	if (RequireNonAbstractType(TInfo->getTypeLoc().getBeginLoc(),
17386	TInfo->getType(),
17387	diag::err_second_parameter_to_va_arg_abstract,
17388	TInfo->getTypeLoc()))
17389	return ExprError();
17390
17391	if (!TInfo->getType().isPODType(Context)) {
17392	Diag(TInfo->getTypeLoc().getBeginLoc(),
17393	TInfo->getType()->isObjCLifetimeType()
17394	? diag::warn_second_parameter_to_va_arg_ownership_qualified
17395	: diag::warn_second_parameter_to_va_arg_not_pod)
17396	<< TInfo->getType()
17397	<< TInfo->getTypeLoc().getSourceRange();
17398	}
17399
17400	// Check for va_arg where arguments of the given type will be promoted
17401	// (i.e. this va_arg is guaranteed to have undefined behavior).
17402	QualType PromoteType;
17403	if (Context.isPromotableIntegerType(T: TInfo->getType())) {
17404	PromoteType = Context.getPromotedIntegerType(PromotableType: TInfo->getType());
17405	// [cstdarg.syn]p1 defers the C++ behavior to what the C standard says,
17406	// and C23 7.16.1.1p2 says, in part:
17407	// If type is not compatible with the type of the actual next argument
17408	// (as promoted according to the default argument promotions), the
17409	// behavior is undefined, except for the following cases:
17410	// - both types are pointers to qualified or unqualified versions of
17411	// compatible types;
17412	// - one type is compatible with a signed integer type, the other
17413	// type is compatible with the corresponding unsigned integer type,
17414	// and the value is representable in both types;
17415	// - one type is pointer to qualified or unqualified void and the
17416	// other is a pointer to a qualified or unqualified character type;
17417	// - or, the type of the next argument is nullptr_t and type is a
17418	// pointer type that has the same representation and alignment
17419	// requirements as a pointer to a character type.
17420	// Given that type compatibility is the primary requirement (ignoring
17421	// qualifications), you would think we could call typesAreCompatible()
17422	// directly to test this. However, in C++, that checks for *same type*,
17423	// which causes false positives when passing an enumeration type to
17424	// va_arg. Instead, get the underlying type of the enumeration and pass
17425	// that.
17426	QualType UnderlyingType = TInfo->getType();
17427	if (const auto *ET = UnderlyingType->getAs<EnumType>())
17428	UnderlyingType = ET->getDecl()->getIntegerType();
17429	if (Context.typesAreCompatible(T1: PromoteType, T2: UnderlyingType,
17430	/*CompareUnqualified*/ true))
17431	PromoteType = QualType();
17432
17433	// If the types are still not compatible, we need to test whether the
17434	// promoted type and the underlying type are the same except for
17435	// signedness. Ask the AST for the correctly corresponding type and see
17436	// if that's compatible.
17437	if (!PromoteType.isNull() && !UnderlyingType->isBooleanType() &&
17438	PromoteType->isUnsignedIntegerType() !=
17439	UnderlyingType->isUnsignedIntegerType()) {
17440	UnderlyingType =
17441	UnderlyingType->isUnsignedIntegerType()
17442	? Context.getCorrespondingSignedType(T: UnderlyingType)
17443	: Context.getCorrespondingUnsignedType(T: UnderlyingType);
17444	if (Context.typesAreCompatible(T1: PromoteType, T2: UnderlyingType,
17445	/*CompareUnqualified*/ true))
17446	PromoteType = QualType();
17447	}
17448	}
17449	if (TInfo->getType()->isSpecificBuiltinType(K: BuiltinType::Float))
17450	PromoteType = Context.DoubleTy;
17451	if (!PromoteType.isNull())
17452	DiagRuntimeBehavior(TInfo->getTypeLoc().getBeginLoc(), E,
17453	PDiag(diag::warn_second_parameter_to_va_arg_never_compatible)
17454	<< TInfo->getType()
17455	<< PromoteType
17456	<< TInfo->getTypeLoc().getSourceRange());
17457	}
17458
17459	QualType T = TInfo->getType().getNonLValueExprType(Context);
17460	return new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T, IsMS);
17461	}
17462
17463	ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) {
17464	// The type of __null will be int or long, depending on the size of
17465	// pointers on the target.
17466	QualType Ty;
17467	unsigned pw = Context.getTargetInfo().getPointerWidth(AddrSpace: LangAS::Default);
17468	if (pw == Context.getTargetInfo().getIntWidth())
17469	Ty = Context.IntTy;
17470	else if (pw == Context.getTargetInfo().getLongWidth())
17471	Ty = Context.LongTy;
17472	else if (pw == Context.getTargetInfo().getLongLongWidth())
17473	Ty = Context.LongLongTy;
17474	else {
17475	llvm_unreachable("I don't know size of pointer!");
17476	}
17477
17478	return new (Context) GNUNullExpr(Ty, TokenLoc);
17479	}
17480
17481	static CXXRecordDecl *LookupStdSourceLocationImpl(Sema &S, SourceLocation Loc) {
17482	CXXRecordDecl *ImplDecl = nullptr;
17483
17484	// Fetch the std::source_location::__impl decl.
17485	if (NamespaceDecl *Std = S.getStdNamespace()) {
17486	LookupResult ResultSL(S, &S.PP.getIdentifierTable().get(Name: "source_location"),
17487	Loc, Sema::LookupOrdinaryName);
17488	if (S.LookupQualifiedName(ResultSL, Std)) {
17489	if (auto *SLDecl = ResultSL.getAsSingle<RecordDecl>()) {
17490	LookupResult ResultImpl(S, &S.PP.getIdentifierTable().get(Name: "__impl"),
17491	Loc, Sema::LookupOrdinaryName);
17492	if ((SLDecl->isCompleteDefinition() || SLDecl->isBeingDefined()) &&
17493	S.LookupQualifiedName(ResultImpl, SLDecl)) {
17494	ImplDecl = ResultImpl.getAsSingle<CXXRecordDecl>();
17495	}
17496	}
17497	}
17498	}
17499
17500	if (!ImplDecl || !ImplDecl->isCompleteDefinition()) {
17501	S.Diag(Loc, diag::err_std_source_location_impl_not_found);
17502	return nullptr;
17503	}
17504
17505	// Verify that __impl is a trivial struct type, with no base classes, and with
17506	// only the four expected fields.
17507	if (ImplDecl->isUnion() || !ImplDecl->isStandardLayout() ||
17508	ImplDecl->getNumBases() != 0) {
17509	S.Diag(Loc, diag::err_std_source_location_impl_malformed);
17510	return nullptr;
17511	}
17512
17513	unsigned Count = 0;
17514	for (FieldDecl *F : ImplDecl->fields()) {
17515	StringRef Name = F->getName();
17516
17517	if (Name == "_M_file_name") {
17518	if (F->getType() !=
17519	S.Context.getPointerType(S.Context.CharTy.withConst()))
17520	break;
17521	Count++;
17522	} else if (Name == "_M_function_name") {
17523	if (F->getType() !=
17524	S.Context.getPointerType(S.Context.CharTy.withConst()))
17525	break;
17526	Count++;
17527	} else if (Name == "_M_line") {
17528	if (!F->getType()->isIntegerType())
17529	break;
17530	Count++;
17531	} else if (Name == "_M_column") {
17532	if (!F->getType()->isIntegerType())
17533	break;
17534	Count++;
17535	} else {
17536	Count = 100; // invalid
17537	break;
17538	}
17539	}
17540	if (Count != 4) {
17541	S.Diag(Loc, diag::err_std_source_location_impl_malformed);
17542	return nullptr;
17543	}
17544
17545	return ImplDecl;
17546	}
17547
17548	ExprResult Sema::ActOnSourceLocExpr(SourceLocIdentKind Kind,
17549	SourceLocation BuiltinLoc,
17550	SourceLocation RPLoc) {
17551	QualType ResultTy;
17552	switch (Kind) {
17553	case SourceLocIdentKind::File:
17554	case SourceLocIdentKind::FileName:
17555	case SourceLocIdentKind::Function:
17556	case SourceLocIdentKind::FuncSig: {
17557	QualType ArrTy = Context.getStringLiteralArrayType(EltTy: Context.CharTy, Length: 0);
17558	ResultTy =
17559	Context.getPointerType(ArrTy->getAsArrayTypeUnsafe()->getElementType());
17560	break;
17561	}
17562	case SourceLocIdentKind::Line:
17563	case SourceLocIdentKind::Column:
17564	ResultTy = Context.UnsignedIntTy;
17565	break;
17566	case SourceLocIdentKind::SourceLocStruct:
17567	if (!StdSourceLocationImplDecl) {
17568	StdSourceLocationImplDecl =
17569	LookupStdSourceLocationImpl(S&: *this, Loc: BuiltinLoc);
17570	if (!StdSourceLocationImplDecl)
17571	return ExprError();
17572	}
17573	ResultTy = Context.getPointerType(
17574	T: Context.getRecordType(Decl: StdSourceLocationImplDecl).withConst());
17575	break;
17576	}
17577
17578	return BuildSourceLocExpr(Kind, ResultTy, BuiltinLoc, RPLoc, ParentContext: CurContext);
17579	}
17580
17581	ExprResult Sema::BuildSourceLocExpr(SourceLocIdentKind Kind, QualType ResultTy,
17582	SourceLocation BuiltinLoc,
17583	SourceLocation RPLoc,
17584	DeclContext *ParentContext) {
17585	return new (Context)
17586	SourceLocExpr(Context, Kind, ResultTy, BuiltinLoc, RPLoc, ParentContext);
17587	}
17588
17589	bool Sema::CheckConversionToObjCLiteral(QualType DstType, Expr *&Exp,
17590	bool Diagnose) {
17591	if (!getLangOpts().ObjC)
17592	return false;
17593
17594	const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>();
17595	if (!PT)
17596	return false;
17597	const ObjCInterfaceDecl *ID = PT->getInterfaceDecl();
17598
17599	// Ignore any parens, implicit casts (should only be
17600	// array-to-pointer decays), and not-so-opaque values. The last is
17601	// important for making this trigger for property assignments.
17602	Expr *SrcExpr = Exp->IgnoreParenImpCasts();
17603	if (OpaqueValueExpr *OV = dyn_cast<OpaqueValueExpr>(Val: SrcExpr))
17604	if (OV->getSourceExpr())
17605	SrcExpr = OV->getSourceExpr()->IgnoreParenImpCasts();
17606
17607	if (auto *SL = dyn_cast<StringLiteral>(Val: SrcExpr)) {
17608	if (!PT->isObjCIdType() &&
17609	!(ID && ID->getIdentifier()->isStr("NSString")))
17610	return false;
17611	if (!SL->isOrdinary())
17612	return false;
17613
17614	if (Diagnose) {
17615	Diag(SL->getBeginLoc(), diag::err_missing_atsign_prefix)
17616	<< /*string*/0 << FixItHint::CreateInsertion(SL->getBeginLoc(), "@");
17617	Exp = BuildObjCStringLiteral(AtLoc: SL->getBeginLoc(), S: SL).get();
17618	}
17619	return true;
17620	}
17621
17622	if ((isa<IntegerLiteral>(Val: SrcExpr) || isa<CharacterLiteral>(Val: SrcExpr) ||
17623	isa<FloatingLiteral>(Val: SrcExpr) || isa<ObjCBoolLiteralExpr>(Val: SrcExpr) ||
17624	isa<CXXBoolLiteralExpr>(Val: SrcExpr)) &&
17625	!SrcExpr->isNullPointerConstant(
17626	Ctx&: getASTContext(), NPC: Expr::NPC_NeverValueDependent)) {
17627	if (!ID || !ID->getIdentifier()->isStr("NSNumber"))
17628	return false;
17629	if (Diagnose) {
17630	Diag(SrcExpr->getBeginLoc(), diag::err_missing_atsign_prefix)
17631	<< /*number*/1
17632	<< FixItHint::CreateInsertion(SrcExpr->getBeginLoc(), "@");
17633	Expr *NumLit =
17634	BuildObjCNumericLiteral(AtLoc: SrcExpr->getBeginLoc(), Number: SrcExpr).get();
17635	if (NumLit)
17636	Exp = NumLit;
17637	}
17638	return true;
17639	}
17640
17641	return false;
17642	}
17643
17644	static bool maybeDiagnoseAssignmentToFunction(Sema &S, QualType DstType,
17645	const Expr *SrcExpr) {
17646	if (!DstType->isFunctionPointerType() ||
17647	!SrcExpr->getType()->isFunctionType())
17648	return false;
17649
17650	auto *DRE = dyn_cast<DeclRefExpr>(Val: SrcExpr->IgnoreParenImpCasts());
17651	if (!DRE)
17652	return false;
17653
17654	auto *FD = dyn_cast<FunctionDecl>(Val: DRE->getDecl());
17655	if (!FD)
17656	return false;
17657
17658	return !S.checkAddressOfFunctionIsAvailable(Function: FD,
17659	/*Complain=*/true,
17660	Loc: SrcExpr->getBeginLoc());
17661	}
17662
17663	bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy,
17664	SourceLocation Loc,
17665	QualType DstType, QualType SrcType,
17666	Expr *SrcExpr, AssignmentAction Action,
17667	bool *Complained) {
17668	if (Complained)
17669	*Complained = false;
17670
17671	// Decode the result (notice that AST's are still created for extensions).
17672	bool CheckInferredResultType = false;
17673	bool isInvalid = false;
17674	unsigned DiagKind = 0;
17675	ConversionFixItGenerator ConvHints;
17676	bool MayHaveConvFixit = false;
17677	bool MayHaveFunctionDiff = false;
17678	const ObjCInterfaceDecl *IFace = nullptr;
17679	const ObjCProtocolDecl *PDecl = nullptr;
17680
17681	switch (ConvTy) {
17682	case Compatible:
17683	DiagnoseAssignmentEnum(DstType, SrcType, SrcExpr);
17684	return false;
17685
17686	case PointerToInt:
17687	if (getLangOpts().CPlusPlus) {
17688	DiagKind = diag::err_typecheck_convert_pointer_int;
17689	isInvalid = true;
17690	} else {
17691	DiagKind = diag::ext_typecheck_convert_pointer_int;
17692	}
17693	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17694	MayHaveConvFixit = true;
17695	break;
17696	case IntToPointer:
17697	if (getLangOpts().CPlusPlus) {
17698	DiagKind = diag::err_typecheck_convert_int_pointer;
17699	isInvalid = true;
17700	} else {
17701	DiagKind = diag::ext_typecheck_convert_int_pointer;
17702	}
17703	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17704	MayHaveConvFixit = true;
17705	break;
17706	case IncompatibleFunctionPointerStrict:
17707	DiagKind =
17708	diag::warn_typecheck_convert_incompatible_function_pointer_strict;
17709	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17710	MayHaveConvFixit = true;
17711	break;
17712	case IncompatibleFunctionPointer:
17713	if (getLangOpts().CPlusPlus) {
17714	DiagKind = diag::err_typecheck_convert_incompatible_function_pointer;
17715	isInvalid = true;
17716	} else {
17717	DiagKind = diag::ext_typecheck_convert_incompatible_function_pointer;
17718	}
17719	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17720	MayHaveConvFixit = true;
17721	break;
17722	case IncompatiblePointer:
17723	if (Action == AA_Passing_CFAudited) {
17724	DiagKind = diag::err_arc_typecheck_convert_incompatible_pointer;
17725	} else if (getLangOpts().CPlusPlus) {
17726	DiagKind = diag::err_typecheck_convert_incompatible_pointer;
17727	isInvalid = true;
17728	} else {
17729	DiagKind = diag::ext_typecheck_convert_incompatible_pointer;
17730	}
17731	CheckInferredResultType = DstType->isObjCObjectPointerType() &&
17732	SrcType->isObjCObjectPointerType();
17733	if (!CheckInferredResultType) {
17734	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17735	} else if (CheckInferredResultType) {
17736	SrcType = SrcType.getUnqualifiedType();
17737	DstType = DstType.getUnqualifiedType();
17738	}
17739	MayHaveConvFixit = true;
17740	break;
17741	case IncompatiblePointerSign:
17742	if (getLangOpts().CPlusPlus) {
17743	DiagKind = diag::err_typecheck_convert_incompatible_pointer_sign;
17744	isInvalid = true;
17745	} else {
17746	DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign;
17747	}
17748	break;
17749	case FunctionVoidPointer:
17750	if (getLangOpts().CPlusPlus) {
17751	DiagKind = diag::err_typecheck_convert_pointer_void_func;
17752	isInvalid = true;
17753	} else {
17754	DiagKind = diag::ext_typecheck_convert_pointer_void_func;
17755	}
17756	break;
17757	case IncompatiblePointerDiscardsQualifiers: {
17758	// Perform array-to-pointer decay if necessary.
17759	if (SrcType->isArrayType()) SrcType = Context.getArrayDecayedType(T: SrcType);
17760
17761	isInvalid = true;
17762
17763	Qualifiers lhq = SrcType->getPointeeType().getQualifiers();
17764	Qualifiers rhq = DstType->getPointeeType().getQualifiers();
17765	if (lhq.getAddressSpace() != rhq.getAddressSpace()) {
17766	DiagKind = diag::err_typecheck_incompatible_address_space;
17767	break;
17768
17769	} else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) {
17770	DiagKind = diag::err_typecheck_incompatible_ownership;
17771	break;
17772	}
17773
17774	llvm_unreachable("unknown error case for discarding qualifiers!");
17775	// fallthrough
17776	}
17777	case CompatiblePointerDiscardsQualifiers:
17778	// If the qualifiers lost were because we were applying the
17779	// (deprecated) C++ conversion from a string literal to a char*
17780	// (or wchar_t*), then there was no error (C++ 4.2p2). FIXME:
17781	// Ideally, this check would be performed in
17782	// checkPointerTypesForAssignment. However, that would require a
17783	// bit of refactoring (so that the second argument is an
17784	// expression, rather than a type), which should be done as part
17785	// of a larger effort to fix checkPointerTypesForAssignment for
17786	// C++ semantics.
17787	if (getLangOpts().CPlusPlus &&
17788	IsStringLiteralToNonConstPointerConversion(From: SrcExpr, ToType: DstType))
17789	return false;
17790	if (getLangOpts().CPlusPlus) {
17791	DiagKind = diag::err_typecheck_convert_discards_qualifiers;
17792	isInvalid = true;
17793	} else {
17794	DiagKind = diag::ext_typecheck_convert_discards_qualifiers;
17795	}
17796
17797	break;
17798	case IncompatibleNestedPointerQualifiers:
17799	if (getLangOpts().CPlusPlus) {
17800	isInvalid = true;
17801	DiagKind = diag::err_nested_pointer_qualifier_mismatch;
17802	} else {
17803	DiagKind = diag::ext_nested_pointer_qualifier_mismatch;
17804	}
17805	break;
17806	case IncompatibleNestedPointerAddressSpaceMismatch:
17807	DiagKind = diag::err_typecheck_incompatible_nested_address_space;
17808	isInvalid = true;
17809	break;
17810	case IntToBlockPointer:
17811	DiagKind = diag::err_int_to_block_pointer;
17812	isInvalid = true;
17813	break;
17814	case IncompatibleBlockPointer:
17815	DiagKind = diag::err_typecheck_convert_incompatible_block_pointer;
17816	isInvalid = true;
17817	break;
17818	case IncompatibleObjCQualifiedId: {
17819	if (SrcType->isObjCQualifiedIdType()) {
17820	const ObjCObjectPointerType *srcOPT =
17821	SrcType->castAs<ObjCObjectPointerType>();
17822	for (auto *srcProto : srcOPT->quals()) {
17823	PDecl = srcProto;
17824	break;
17825	}
17826	if (const ObjCInterfaceType *IFaceT =
17827	DstType->castAs<ObjCObjectPointerType>()->getInterfaceType())
17828	IFace = IFaceT->getDecl();
17829	}
17830	else if (DstType->isObjCQualifiedIdType()) {
17831	const ObjCObjectPointerType *dstOPT =
17832	DstType->castAs<ObjCObjectPointerType>();
17833	for (auto *dstProto : dstOPT->quals()) {
17834	PDecl = dstProto;
17835	break;
17836	}
17837	if (const ObjCInterfaceType *IFaceT =
17838	SrcType->castAs<ObjCObjectPointerType>()->getInterfaceType())
17839	IFace = IFaceT->getDecl();
17840	}
17841	if (getLangOpts().CPlusPlus) {
17842	DiagKind = diag::err_incompatible_qualified_id;
17843	isInvalid = true;
17844	} else {
17845	DiagKind = diag::warn_incompatible_qualified_id;
17846	}
17847	break;
17848	}
17849	case IncompatibleVectors:
17850	if (getLangOpts().CPlusPlus) {
17851	DiagKind = diag::err_incompatible_vectors;
17852	isInvalid = true;
17853	} else {
17854	DiagKind = diag::warn_incompatible_vectors;
17855	}
17856	break;
17857	case IncompatibleObjCWeakRef:
17858	DiagKind = diag::err_arc_weak_unavailable_assign;
17859	isInvalid = true;
17860	break;
17861	case Incompatible:
17862	if (maybeDiagnoseAssignmentToFunction(S&: *this, DstType, SrcExpr)) {
17863	if (Complained)
17864	*Complained = true;
17865	return true;
17866	}
17867
17868	DiagKind = diag::err_typecheck_convert_incompatible;
17869	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17870	MayHaveConvFixit = true;
17871	isInvalid = true;
17872	MayHaveFunctionDiff = true;
17873	break;
17874	}
17875
17876	QualType FirstType, SecondType;
17877	switch (Action) {
17878	case AA_Assigning:
17879	case AA_Initializing:
17880	// The destination type comes first.
17881	FirstType = DstType;
17882	SecondType = SrcType;
17883	break;
17884
17885	case AA_Returning:
17886	case AA_Passing:
17887	case AA_Passing_CFAudited:
17888	case AA_Converting:
17889	case AA_Sending:
17890	case AA_Casting:
17891	// The source type comes first.
17892	FirstType = SrcType;
17893	SecondType = DstType;
17894	break;
17895	}
17896
17897	PartialDiagnostic FDiag = PDiag(DiagID: DiagKind);
17898	AssignmentAction ActionForDiag = Action;
17899	if (Action == AA_Passing_CFAudited)
17900	ActionForDiag = AA_Passing;
17901
17902	FDiag << FirstType << SecondType << ActionForDiag
17903	<< SrcExpr->getSourceRange();
17904
17905	if (DiagKind == diag::ext_typecheck_convert_incompatible_pointer_sign ||
17906	DiagKind == diag::err_typecheck_convert_incompatible_pointer_sign) {
17907	auto isPlainChar = [](const clang::Type *Type) {
17908	return Type->isSpecificBuiltinType(K: BuiltinType::Char_S) ||
17909	Type->isSpecificBuiltinType(K: BuiltinType::Char_U);
17910	};
17911	FDiag << (isPlainChar(FirstType->getPointeeOrArrayElementType()) ||
17912	isPlainChar(SecondType->getPointeeOrArrayElementType()));
17913	}
17914
17915	// If we can fix the conversion, suggest the FixIts.
17916	if (!ConvHints.isNull()) {
17917	for (FixItHint &H : ConvHints.Hints)
17918	FDiag << H;
17919	}
17920
17921	if (MayHaveConvFixit) { FDiag << (unsigned) (ConvHints.Kind); }
17922
17923	if (MayHaveFunctionDiff)
17924	HandleFunctionTypeMismatch(PDiag&: FDiag, FromType: SecondType, ToType: FirstType);
17925
17926	Diag(Loc, PD: FDiag);
17927	if ((DiagKind == diag::warn_incompatible_qualified_id ||
17928	DiagKind == diag::err_incompatible_qualified_id) &&
17929	PDecl && IFace && !IFace->hasDefinition())
17930	Diag(IFace->getLocation(), diag::note_incomplete_class_and_qualified_id)
17931	<< IFace << PDecl;
17932
17933	if (SecondType == Context.OverloadTy)
17934	NoteAllOverloadCandidates(OverloadExpr::find(E: SrcExpr).Expression,
17935	FirstType, /*TakingAddress=*/true);
17936
17937	if (CheckInferredResultType)
17938	EmitRelatedResultTypeNote(E: SrcExpr);
17939
17940	if (Action == AA_Returning && ConvTy == IncompatiblePointer)
17941	EmitRelatedResultTypeNoteForReturn(destType: DstType);
17942
17943	if (Complained)
17944	*Complained = true;
17945	return isInvalid;
17946	}
17947
17948	ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
17949	llvm::APSInt *Result,
17950	AllowFoldKind CanFold) {
17951	class SimpleICEDiagnoser : public VerifyICEDiagnoser {
17952	public:
17953	SemaDiagnosticBuilder diagnoseNotICEType(Sema &S, SourceLocation Loc,
17954	QualType T) override {
17955	return S.Diag(Loc, diag::err_ice_not_integral)
17956	<< T << S.LangOpts.CPlusPlus;
17957	}
17958	SemaDiagnosticBuilder diagnoseNotICE(Sema &S, SourceLocation Loc) override {
17959	return S.Diag(Loc, diag::err_expr_not_ice) << S.LangOpts.CPlusPlus;
17960	}
17961	} Diagnoser;
17962
17963	return VerifyIntegerConstantExpression(E, Result, Diagnoser, CanFold);
17964	}
17965
17966	ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
17967	llvm::APSInt *Result,
17968	unsigned DiagID,
17969	AllowFoldKind CanFold) {
17970	class IDDiagnoser : public VerifyICEDiagnoser {
17971	unsigned DiagID;
17972
17973	public:
17974	IDDiagnoser(unsigned DiagID)
17975	: VerifyICEDiagnoser(DiagID == 0), DiagID(DiagID) { }
17976
17977	SemaDiagnosticBuilder diagnoseNotICE(Sema &S, SourceLocation Loc) override {
17978	return S.Diag(Loc, DiagID);
17979	}
17980	} Diagnoser(DiagID);
17981
17982	return VerifyIntegerConstantExpression(E, Result, Diagnoser, CanFold);
17983	}
17984
17985	Sema::SemaDiagnosticBuilder
17986	Sema::VerifyICEDiagnoser::diagnoseNotICEType(Sema &S, SourceLocation Loc,
17987	QualType T) {
17988	return diagnoseNotICE(S, Loc);
17989	}
17990
17991	Sema::SemaDiagnosticBuilder
17992	Sema::VerifyICEDiagnoser::diagnoseFold(Sema &S, SourceLocation Loc) {
17993	return S.Diag(Loc, diag::ext_expr_not_ice) << S.LangOpts.CPlusPlus;
17994	}
17995
17996	ExprResult
17997	Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
17998	VerifyICEDiagnoser &Diagnoser,
17999	AllowFoldKind CanFold) {
18000	SourceLocation DiagLoc = E->getBeginLoc();
18001
18002	if (getLangOpts().CPlusPlus11) {
18003	// C++11 [expr.const]p5:
18004	// If an expression of literal class type is used in a context where an
18005	// integral constant expression is required, then that class type shall
18006	// have a single non-explicit conversion function to an integral or
18007	// unscoped enumeration type
18008	ExprResult Converted;
18009	class CXX11ConvertDiagnoser : public ICEConvertDiagnoser {
18010	VerifyICEDiagnoser &BaseDiagnoser;
18011	public:
18012	CXX11ConvertDiagnoser(VerifyICEDiagnoser &BaseDiagnoser)
18013	: ICEConvertDiagnoser(/*AllowScopedEnumerations*/ false,
18014	BaseDiagnoser.Suppress, true),
18015	BaseDiagnoser(BaseDiagnoser) {}
18016
18017	SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
18018	QualType T) override {
18019	return BaseDiagnoser.diagnoseNotICEType(S, Loc, T);
18020	}
18021
18022	SemaDiagnosticBuilder diagnoseIncomplete(
18023	Sema &S, SourceLocation Loc, QualType T) override {
18024	return S.Diag(Loc, diag::err_ice_incomplete_type) << T;
18025	}
18026
18027	SemaDiagnosticBuilder diagnoseExplicitConv(
18028	Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
18029	return S.Diag(Loc, diag::err_ice_explicit_conversion) << T << ConvTy;
18030	}
18031
18032	SemaDiagnosticBuilder noteExplicitConv(
18033	Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
18034	return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here)
18035	<< ConvTy->isEnumeralType() << ConvTy;
18036	}
18037
18038	SemaDiagnosticBuilder diagnoseAmbiguous(
18039	Sema &S, SourceLocation Loc, QualType T) override {
18040	return S.Diag(Loc, diag::err_ice_ambiguous_conversion) << T;
18041	}
18042
18043	SemaDiagnosticBuilder noteAmbiguous(
18044	Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
18045	return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here)
18046	<< ConvTy->isEnumeralType() << ConvTy;
18047	}
18048
18049	SemaDiagnosticBuilder diagnoseConversion(
18050	Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
18051	llvm_unreachable("conversion functions are permitted");
18052	}
18053	} ConvertDiagnoser(Diagnoser);
18054
18055	Converted = PerformContextualImplicitConversion(Loc: DiagLoc, FromE: E,
18056	Converter&: ConvertDiagnoser);
18057	if (Converted.isInvalid())
18058	return Converted;
18059	E = Converted.get();
18060	if (!E->getType()->isIntegralOrUnscopedEnumerationType())
18061	return ExprError();
18062	} else if (!E->getType()->isIntegralOrUnscopedEnumerationType()) {
18063	// An ICE must be of integral or unscoped enumeration type.
18064	if (!Diagnoser.Suppress)
18065	Diagnoser.diagnoseNotICEType(S&: *this, Loc: DiagLoc, T: E->getType())
18066	<< E->getSourceRange();
18067	return ExprError();
18068	}
18069
18070	ExprResult RValueExpr = DefaultLvalueConversion(E);
18071	if (RValueExpr.isInvalid())
18072	return ExprError();
18073
18074	E = RValueExpr.get();
18075
18076	// Circumvent ICE checking in C++11 to avoid evaluating the expression twice
18077	// in the non-ICE case.
18078	if (!getLangOpts().CPlusPlus11 && E->isIntegerConstantExpr(Ctx: Context)) {
18079	if (Result)
18080	*Result = E->EvaluateKnownConstIntCheckOverflow(Ctx: Context);
18081	if (!isa<ConstantExpr>(Val: E))
18082	E = Result ? ConstantExpr::Create(Context, E, Result: APValue(*Result))
18083	: ConstantExpr::Create(Context, E);
18084	return E;
18085	}
18086
18087	Expr::EvalResult EvalResult;
18088	SmallVector<PartialDiagnosticAt, 8> Notes;
18089	EvalResult.Diag = &Notes;
18090
18091	// Try to evaluate the expression, and produce diagnostics explaining why it's
18092	// not a constant expression as a side-effect.
18093	bool Folded =
18094	E->EvaluateAsRValue(Result&: EvalResult, Ctx: Context, /*isConstantContext*/ InConstantContext: true) &&
18095	EvalResult.Val.isInt() && !EvalResult.HasSideEffects;
18096
18097	if (!isa<ConstantExpr>(Val: E))
18098	E = ConstantExpr::Create(Context, E, Result: EvalResult.Val);
18099
18100	// In C++11, we can rely on diagnostics being produced for any expression
18101	// which is not a constant expression. If no diagnostics were produced, then
18102	// this is a constant expression.
18103	if (Folded && getLangOpts().CPlusPlus11 && Notes.empty()) {
18104	if (Result)
18105	*Result = EvalResult.Val.getInt();
18106	return E;
18107	}
18108
18109	// If our only note is the usual "invalid subexpression" note, just point
18110	// the caret at its location rather than producing an essentially
18111	// redundant note.
18112	if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
18113	diag::note_invalid_subexpr_in_const_expr) {
18114	DiagLoc = Notes[0].first;
18115	Notes.clear();
18116	}
18117
18118	if (!Folded || !CanFold) {
18119	if (!Diagnoser.Suppress) {
18120	Diagnoser.diagnoseNotICE(S&: *this, Loc: DiagLoc) << E->getSourceRange();
18121	for (const PartialDiagnosticAt &Note : Notes)
18122	Diag(Loc: Note.first, PD: Note.second);
18123	}
18124
18125	return ExprError();
18126	}
18127
18128	Diagnoser.diagnoseFold(S&: *this, Loc: DiagLoc) << E->getSourceRange();
18129	for (const PartialDiagnosticAt &Note : Notes)
18130	Diag(Loc: Note.first, PD: Note.second);
18131
18132	if (Result)
18133	*Result = EvalResult.Val.getInt();
18134	return E;
18135	}
18136
18137	namespace {
18138	// Handle the case where we conclude a expression which we speculatively
18139	// considered to be unevaluated is actually evaluated.
18140	class TransformToPE : public TreeTransform<TransformToPE> {
18141	typedef TreeTransform<TransformToPE> BaseTransform;
18142
18143	public:
18144	TransformToPE(Sema &SemaRef) : BaseTransform(SemaRef) { }
18145
18146	// Make sure we redo semantic analysis
18147	bool AlwaysRebuild() { return true; }
18148	bool ReplacingOriginal() { return true; }
18149
18150	// We need to special-case DeclRefExprs referring to FieldDecls which
18151	// are not part of a member pointer formation; normal TreeTransforming
18152	// doesn't catch this case because of the way we represent them in the AST.
18153	// FIXME: This is a bit ugly; is it really the best way to handle this
18154	// case?
18155	//
18156	// Error on DeclRefExprs referring to FieldDecls.
18157	ExprResult TransformDeclRefExpr(DeclRefExpr *E) {
18158	if (isa<FieldDecl>(E->getDecl()) &&
18159	!SemaRef.isUnevaluatedContext())
18160	return SemaRef.Diag(E->getLocation(),
18161	diag::err_invalid_non_static_member_use)
18162	<< E->getDecl() << E->getSourceRange();
18163
18164	return BaseTransform::TransformDeclRefExpr(E);
18165	}
18166
18167	// Exception: filter out member pointer formation
18168	ExprResult TransformUnaryOperator(UnaryOperator *E) {
18169	if (E->getOpcode() == UO_AddrOf && E->getType()->isMemberPointerType())
18170	return E;
18171
18172	return BaseTransform::TransformUnaryOperator(E);
18173	}
18174
18175	// The body of a lambda-expression is in a separate expression evaluation
18176	// context so never needs to be transformed.
18177	// FIXME: Ideally we wouldn't transform the closure type either, and would
18178	// just recreate the capture expressions and lambda expression.
18179	StmtResult TransformLambdaBody(LambdaExpr *E, Stmt *Body) {
18180	return SkipLambdaBody(E, Body);
18181	}
18182	};
18183	}
18184
18185	ExprResult Sema::TransformToPotentiallyEvaluated(Expr *E) {
18186	assert(isUnevaluatedContext() &&
18187	"Should only transform unevaluated expressions");
18188	ExprEvalContexts.back().Context =
18189	ExprEvalContexts[ExprEvalContexts.size()-2].Context;
18190	if (isUnevaluatedContext())
18191	return E;
18192	return TransformToPE(*this).TransformExpr(E);
18193	}
18194
18195	TypeSourceInfo *Sema::TransformToPotentiallyEvaluated(TypeSourceInfo *TInfo) {
18196	assert(isUnevaluatedContext() &&
18197	"Should only transform unevaluated expressions");
18198	ExprEvalContexts.back().Context =
18199	ExprEvalContexts[ExprEvalContexts.size() - 2].Context;
18200	if (isUnevaluatedContext())
18201	return TInfo;
18202	return TransformToPE(*this).TransformType(TInfo);
18203	}
18204
18205	void
18206	Sema::PushExpressionEvaluationContext(
18207	ExpressionEvaluationContext NewContext, Decl *LambdaContextDecl,
18208	ExpressionEvaluationContextRecord::ExpressionKind ExprContext) {
18209	ExprEvalContexts.emplace_back(Args&: NewContext, Args: ExprCleanupObjects.size(), Args&: Cleanup,
18210	Args&: LambdaContextDecl, Args&: ExprContext);
18211
18212	// Discarded statements and immediate contexts nested in other
18213	// discarded statements or immediate context are themselves
18214	// a discarded statement or an immediate context, respectively.
18215	ExprEvalContexts.back().InDiscardedStatement =
18216	ExprEvalContexts[ExprEvalContexts.size() - 2]
18217	.isDiscardedStatementContext();
18218
18219	// C++23 [expr.const]/p15
18220	// An expression or conversion is in an immediate function context if [...]
18221	// it is a subexpression of a manifestly constant-evaluated expression or
18222	// conversion.
18223	const auto &Prev = ExprEvalContexts[ExprEvalContexts.size() - 2];
18224	ExprEvalContexts.back().InImmediateFunctionContext =
18225	Prev.isImmediateFunctionContext() || Prev.isConstantEvaluated();
18226
18227	ExprEvalContexts.back().InImmediateEscalatingFunctionContext =
18228	Prev.InImmediateEscalatingFunctionContext;
18229
18230	Cleanup.reset();
18231	if (!MaybeODRUseExprs.empty())
18232	std::swap(LHS&: MaybeODRUseExprs, RHS&: ExprEvalContexts.back().SavedMaybeODRUseExprs);
18233	}
18234
18235	void
18236	Sema::PushExpressionEvaluationContext(
18237	ExpressionEvaluationContext NewContext, ReuseLambdaContextDecl_t,
18238	ExpressionEvaluationContextRecord::ExpressionKind ExprContext) {
18239	Decl *ClosureContextDecl = ExprEvalContexts.back().ManglingContextDecl;
18240	PushExpressionEvaluationContext(NewContext, LambdaContextDecl: ClosureContextDecl, ExprContext);
18241	}
18242
18243	namespace {
18244
18245	const DeclRefExpr *CheckPossibleDeref(Sema &S, const Expr *PossibleDeref) {
18246	PossibleDeref = PossibleDeref->IgnoreParenImpCasts();
18247	if (const auto *E = dyn_cast<UnaryOperator>(Val: PossibleDeref)) {
18248	if (E->getOpcode() == UO_Deref)
18249	return CheckPossibleDeref(S, PossibleDeref: E->getSubExpr());
18250	} else if (const auto *E = dyn_cast<ArraySubscriptExpr>(Val: PossibleDeref)) {
18251	return CheckPossibleDeref(S, PossibleDeref: E->getBase());
18252	} else if (const auto *E = dyn_cast<MemberExpr>(Val: PossibleDeref)) {
18253	return CheckPossibleDeref(S, PossibleDeref: E->getBase());
18254	} else if (const auto E = dyn_cast<DeclRefExpr>(Val: PossibleDeref)) {
18255	QualType Inner;
18256	QualType Ty = E->getType();
18257	if (const auto *Ptr = Ty->getAs<PointerType>())
18258	Inner = Ptr->getPointeeType();
18259	else if (const auto *Arr = S.Context.getAsArrayType(Ty))
18260	Inner = Arr->getElementType();
18261	else
18262	return nullptr;
18263
18264	if (Inner->hasAttr(attr::NoDeref))
18265	return E;
18266	}
18267	return nullptr;
18268	}
18269
18270	} // namespace
18271
18272	void Sema::WarnOnPendingNoDerefs(ExpressionEvaluationContextRecord &Rec) {
18273	for (const Expr *E : Rec.PossibleDerefs) {
18274	const DeclRefExpr *DeclRef = CheckPossibleDeref(S&: *this, PossibleDeref: E);
18275	if (DeclRef) {
18276	const ValueDecl *Decl = DeclRef->getDecl();
18277	Diag(E->getExprLoc(), diag::warn_dereference_of_noderef_type)
18278	<< Decl->getName() << E->getSourceRange();
18279	Diag(Decl->getLocation(), diag::note_previous_decl) << Decl->getName();
18280	} else {
18281	Diag(E->getExprLoc(), diag::warn_dereference_of_noderef_type_no_decl)
18282	<< E->getSourceRange();
18283	}
18284	}
18285	Rec.PossibleDerefs.clear();
18286	}
18287
18288	/// Check whether E, which is either a discarded-value expression or an
18289	/// unevaluated operand, is a simple-assignment to a volatlie-qualified lvalue,
18290	/// and if so, remove it from the list of volatile-qualified assignments that
18291	/// we are going to warn are deprecated.
18292	void Sema::CheckUnusedVolatileAssignment(Expr *E) {
18293	if (!E->getType().isVolatileQualified() || !getLangOpts().CPlusPlus20)
18294	return;
18295
18296	// Note: ignoring parens here is not justified by the standard rules, but
18297	// ignoring parentheses seems like a more reasonable approach, and this only
18298	// drives a deprecation warning so doesn't affect conformance.
18299	if (auto *BO = dyn_cast<BinaryOperator>(Val: E->IgnoreParenImpCasts())) {
18300	if (BO->getOpcode() == BO_Assign) {
18301	auto &LHSs = ExprEvalContexts.back().VolatileAssignmentLHSs;
18302	llvm::erase(C&: LHSs, V: BO->getLHS());
18303	}
18304	}
18305	}
18306
18307	void Sema::MarkExpressionAsImmediateEscalating(Expr *E) {
18308	assert(!FunctionScopes.empty() && "Expected a function scope");
18309	assert(getLangOpts().CPlusPlus20 &&
18310	ExprEvalContexts.back().InImmediateEscalatingFunctionContext &&
18311	"Cannot mark an immediate escalating expression outside of an "
18312	"immediate escalating context");
18313	if (auto *Call = dyn_cast<CallExpr>(Val: E->IgnoreImplicit());
18314	Call && Call->getCallee()) {
18315	if (auto *DeclRef =
18316	dyn_cast<DeclRefExpr>(Val: Call->getCallee()->IgnoreImplicit()))
18317	DeclRef->setIsImmediateEscalating(true);
18318	} else if (auto *Ctr = dyn_cast<CXXConstructExpr>(Val: E->IgnoreImplicit())) {
18319	Ctr->setIsImmediateEscalating(true);
18320	} else if (auto *DeclRef = dyn_cast<DeclRefExpr>(Val: E->IgnoreImplicit())) {
18321	DeclRef->setIsImmediateEscalating(true);
18322	} else {
18323	assert(false && "expected an immediately escalating expression");
18324	}
18325	getCurFunction()->FoundImmediateEscalatingExpression = true;
18326	}
18327
18328	ExprResult Sema::CheckForImmediateInvocation(ExprResult E, FunctionDecl *Decl) {
18329	if (isUnevaluatedContext() || !E.isUsable() || !Decl ||
18330	!Decl->isImmediateFunction() || isAlwaysConstantEvaluatedContext() ||
18331	isCheckingDefaultArgumentOrInitializer() ||
18332	RebuildingImmediateInvocation || isImmediateFunctionContext())
18333	return E;
18334
18335	/// Opportunistically remove the callee from ReferencesToConsteval if we can.
18336	/// It's OK if this fails; we'll also remove this in
18337	/// HandleImmediateInvocations, but catching it here allows us to avoid
18338	/// walking the AST looking for it in simple cases.
18339	if (auto *Call = dyn_cast<CallExpr>(Val: E.get()->IgnoreImplicit()))
18340	if (auto *DeclRef =
18341	dyn_cast<DeclRefExpr>(Val: Call->getCallee()->IgnoreImplicit()))
18342	ExprEvalContexts.back().ReferenceToConsteval.erase(Ptr: DeclRef);
18343
18344	// C++23 [expr.const]/p16
18345	// An expression or conversion is immediate-escalating if it is not initially
18346	// in an immediate function context and it is [...] an immediate invocation
18347	// that is not a constant expression and is not a subexpression of an
18348	// immediate invocation.
18349	APValue Cached;
18350	auto CheckConstantExpressionAndKeepResult = [&]() {
18351	llvm::SmallVector<PartialDiagnosticAt, 8> Notes;
18352	Expr::EvalResult Eval;
18353	Eval.Diag = &Notes;
18354	bool Res = E.get()->EvaluateAsConstantExpr(
18355	Result&: Eval, Ctx: getASTContext(), Kind: ConstantExprKind::ImmediateInvocation);
18356	if (Res && Notes.empty()) {
18357	Cached = std::move(Eval.Val);
18358	return true;
18359	}
18360	return false;
18361	};
18362
18363	if (!E.get()->isValueDependent() &&
18364	ExprEvalContexts.back().InImmediateEscalatingFunctionContext &&
18365	!CheckConstantExpressionAndKeepResult()) {
18366	MarkExpressionAsImmediateEscalating(E: E.get());
18367	return E;
18368	}
18369
18370	if (Cleanup.exprNeedsCleanups()) {
18371	// Since an immediate invocation is a full expression itself - it requires
18372	// an additional ExprWithCleanups node, but it can participate to a bigger
18373	// full expression which actually requires cleanups to be run after so
18374	// create ExprWithCleanups without using MaybeCreateExprWithCleanups as it
18375	// may discard cleanups for outer expression too early.
18376
18377	// Note that ExprWithCleanups created here must always have empty cleanup
18378	// objects:
18379	// - compound literals do not create cleanup objects in C++ and immediate
18380	// invocations are C++-only.
18381	// - blocks are not allowed inside constant expressions and compiler will
18382	// issue an error if they appear there.
18383	//
18384	// Hence, in correct code any cleanup objects created inside current
18385	// evaluation context must be outside the immediate invocation.
18386	E = ExprWithCleanups::Create(C: getASTContext(), subexpr: E.get(),
18387	CleanupsHaveSideEffects: Cleanup.cleanupsHaveSideEffects(), objects: {});
18388	}
18389
18390	ConstantExpr *Res = ConstantExpr::Create(
18391	Context: getASTContext(), E: E.get(),
18392	Storage: ConstantExpr::getStorageKind(T: Decl->getReturnType().getTypePtr(),
18393	Context: getASTContext()),
18394	/*IsImmediateInvocation*/ true);
18395	if (Cached.hasValue())
18396	Res->MoveIntoResult(Value&: Cached, Context: getASTContext());
18397	/// Value-dependent constant expressions should not be immediately
18398	/// evaluated until they are instantiated.
18399	if (!Res->isValueDependent())
18400	ExprEvalContexts.back().ImmediateInvocationCandidates.emplace_back(Args&: Res, Args: 0);
18401	return Res;
18402	}
18403
18404	static void EvaluateAndDiagnoseImmediateInvocation(
18405	Sema &SemaRef, Sema::ImmediateInvocationCandidate Candidate) {
18406	llvm::SmallVector<PartialDiagnosticAt, 8> Notes;
18407	Expr::EvalResult Eval;
18408	Eval.Diag = &Notes;
18409	ConstantExpr *CE = Candidate.getPointer();
18410	bool Result = CE->EvaluateAsConstantExpr(
18411	Eval, SemaRef.getASTContext(), ConstantExprKind::ImmediateInvocation);
18412	if (!Result || !Notes.empty()) {
18413	SemaRef.FailedImmediateInvocations.insert(Ptr: CE);
18414	Expr *InnerExpr = CE->getSubExpr()->IgnoreImplicit();
18415	if (auto *FunctionalCast = dyn_cast<CXXFunctionalCastExpr>(InnerExpr))
18416	InnerExpr = FunctionalCast->getSubExpr()->IgnoreImplicit();
18417	FunctionDecl *FD = nullptr;
18418	if (auto *Call = dyn_cast<CallExpr>(InnerExpr))
18419	FD = cast<FunctionDecl>(Call->getCalleeDecl());
18420	else if (auto *Call = dyn_cast<CXXConstructExpr>(InnerExpr))
18421	FD = Call->getConstructor();
18422	else if (auto *Cast = dyn_cast<CastExpr>(InnerExpr))
18423	FD = dyn_cast_or_null<FunctionDecl>(Cast->getConversionFunction());
18424
18425	assert(FD && FD->isImmediateFunction() &&
18426	"could not find an immediate function in this expression");
18427	if (FD->isInvalidDecl())
18428	return;
18429	SemaRef.Diag(CE->getBeginLoc(), diag::err_invalid_consteval_call)
18430	<< FD << FD->isConsteval();
18431	if (auto Context =
18432	SemaRef.InnermostDeclarationWithDelayedImmediateInvocations()) {
18433	SemaRef.Diag(Context->Loc, diag::note_invalid_consteval_initializer)
18434	<< Context->Decl;
18435	SemaRef.Diag(Context->Decl->getBeginLoc(), diag::note_declared_at);
18436	}
18437	if (!FD->isConsteval())
18438	SemaRef.DiagnoseImmediateEscalatingReason(FD);
18439	for (auto &Note : Notes)
18440	SemaRef.Diag(Loc: Note.first, PD: Note.second);
18441	return;
18442	}
18443	CE->MoveIntoResult(Value&: Eval.Val, Context: SemaRef.getASTContext());
18444	}
18445
18446	static void RemoveNestedImmediateInvocation(
18447	Sema &SemaRef, Sema::ExpressionEvaluationContextRecord &Rec,
18448	SmallVector<Sema::ImmediateInvocationCandidate, 4>::reverse_iterator It) {
18449	struct ComplexRemove : TreeTransform<ComplexRemove> {
18450	using Base = TreeTransform<ComplexRemove>;
18451	llvm::SmallPtrSetImpl<DeclRefExpr *> &DRSet;
18452	SmallVector<Sema::ImmediateInvocationCandidate, 4> &IISet;
18453	SmallVector<Sema::ImmediateInvocationCandidate, 4>::reverse_iterator
18454	CurrentII;
18455	ComplexRemove(Sema &SemaRef, llvm::SmallPtrSetImpl<DeclRefExpr *> &DR,
18456	SmallVector<Sema::ImmediateInvocationCandidate, 4> &II,
18457	SmallVector<Sema::ImmediateInvocationCandidate,
18458	4>::reverse_iterator Current)
18459	: Base(SemaRef), DRSet(DR), IISet(II), CurrentII(Current) {}
18460	void RemoveImmediateInvocation(ConstantExpr* E) {
18461	auto It = std::find_if(first: CurrentII, last: IISet.rend(),
18462	pred: [E](Sema::ImmediateInvocationCandidate Elem) {
18463	return Elem.getPointer() == E;
18464	});
18465	// It is possible that some subexpression of the current immediate
18466	// invocation was handled from another expression evaluation context. Do
18467	// not handle the current immediate invocation if some of its
18468	// subexpressions failed before.
18469	if (It == IISet.rend()) {
18470	if (SemaRef.FailedImmediateInvocations.contains(Ptr: E))
18471	CurrentII->setInt(1);
18472	} else {
18473	It->setInt(1); // Mark as deleted
18474	}
18475	}
18476	ExprResult TransformConstantExpr(ConstantExpr *E) {
18477	if (!E->isImmediateInvocation())
18478	return Base::TransformConstantExpr(E);
18479	RemoveImmediateInvocation(E);
18480	return Base::TransformExpr(E->getSubExpr());
18481	}
18482	/// Base::TransfromCXXOperatorCallExpr doesn't traverse the callee so
18483	/// we need to remove its DeclRefExpr from the DRSet.
18484	ExprResult TransformCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
18485	DRSet.erase(Ptr: cast<DeclRefExpr>(E->getCallee()->IgnoreImplicit()));
18486	return Base::TransformCXXOperatorCallExpr(E);
18487	}
18488	/// Base::TransformUserDefinedLiteral doesn't preserve the
18489	/// UserDefinedLiteral node.
18490	ExprResult TransformUserDefinedLiteral(UserDefinedLiteral *E) { return E; }
18491	/// Base::TransformInitializer skips ConstantExpr so we need to visit them
18492	/// here.
18493	ExprResult TransformInitializer(Expr *Init, bool NotCopyInit) {
18494	if (!Init)
18495	return Init;
18496	/// ConstantExpr are the first layer of implicit node to be removed so if
18497	/// Init isn't a ConstantExpr, no ConstantExpr will be skipped.
18498	if (auto *CE = dyn_cast<ConstantExpr>(Val: Init))
18499	if (CE->isImmediateInvocation())
18500	RemoveImmediateInvocation(E: CE);
18501	return Base::TransformInitializer(Init, NotCopyInit);
18502	}
18503	ExprResult TransformDeclRefExpr(DeclRefExpr *E) {
18504	DRSet.erase(Ptr: E);
18505	return E;
18506	}
18507	ExprResult TransformLambdaExpr(LambdaExpr *E) {
18508	// Do not rebuild lambdas to avoid creating a new type.
18509	// Lambdas have already been processed inside their eval context.
18510	return E;
18511	}
18512	bool AlwaysRebuild() { return false; }
18513	bool ReplacingOriginal() { return true; }
18514	bool AllowSkippingCXXConstructExpr() {
18515	bool Res = AllowSkippingFirstCXXConstructExpr;
18516	AllowSkippingFirstCXXConstructExpr = true;
18517	return Res;
18518	}
18519	bool AllowSkippingFirstCXXConstructExpr = true;
18520	} Transformer(SemaRef, Rec.ReferenceToConsteval,
18521	Rec.ImmediateInvocationCandidates, It);
18522
18523	/// CXXConstructExpr with a single argument are getting skipped by
18524	/// TreeTransform in some situtation because they could be implicit. This
18525	/// can only occur for the top-level CXXConstructExpr because it is used
18526	/// nowhere in the expression being transformed therefore will not be rebuilt.
18527	/// Setting AllowSkippingFirstCXXConstructExpr to false will prevent from
18528	/// skipping the first CXXConstructExpr.
18529	if (isa<CXXConstructExpr>(It->getPointer()->IgnoreImplicit()))
18530	Transformer.AllowSkippingFirstCXXConstructExpr = false;
18531
18532	ExprResult Res = Transformer.TransformExpr(It->getPointer()->getSubExpr());
18533	// The result may not be usable in case of previous compilation errors.
18534	// In this case evaluation of the expression may result in crash so just
18535	// don't do anything further with the result.
18536	if (Res.isUsable()) {
18537	Res = SemaRef.MaybeCreateExprWithCleanups(SubExpr: Res);
18538	It->getPointer()->setSubExpr(Res.get());
18539	}
18540	}
18541
18542	static void
18543	HandleImmediateInvocations(Sema &SemaRef,
18544	Sema::ExpressionEvaluationContextRecord &Rec) {
18545	if ((Rec.ImmediateInvocationCandidates.size() == 0 &&
18546	Rec.ReferenceToConsteval.size() == 0) ||
18547	SemaRef.RebuildingImmediateInvocation)
18548	return;
18549
18550	/// When we have more than 1 ImmediateInvocationCandidates or previously
18551	/// failed immediate invocations, we need to check for nested
18552	/// ImmediateInvocationCandidates in order to avoid duplicate diagnostics.
18553	/// Otherwise we only need to remove ReferenceToConsteval in the immediate
18554	/// invocation.
18555	if (Rec.ImmediateInvocationCandidates.size() > 1 ||
18556	!SemaRef.FailedImmediateInvocations.empty()) {
18557
18558	/// Prevent sema calls during the tree transform from adding pointers that
18559	/// are already in the sets.
18560	llvm::SaveAndRestore DisableIITracking(
18561	SemaRef.RebuildingImmediateInvocation, true);
18562
18563	/// Prevent diagnostic during tree transfrom as they are duplicates
18564	Sema::TentativeAnalysisScope DisableDiag(SemaRef);
18565
18566	for (auto It = Rec.ImmediateInvocationCandidates.rbegin();
18567	It != Rec.ImmediateInvocationCandidates.rend(); It++)
18568	if (!It->getInt())
18569	RemoveNestedImmediateInvocation(SemaRef, Rec, It);
18570	} else if (Rec.ImmediateInvocationCandidates.size() == 1 &&
18571	Rec.ReferenceToConsteval.size()) {
18572	struct SimpleRemove : RecursiveASTVisitor<SimpleRemove> {
18573	llvm::SmallPtrSetImpl<DeclRefExpr *> &DRSet;
18574	SimpleRemove(llvm::SmallPtrSetImpl<DeclRefExpr *> &S) : DRSet(S) {}
18575	bool VisitDeclRefExpr(DeclRefExpr *E) {
18576	DRSet.erase(Ptr: E);
18577	return DRSet.size();
18578	}
18579	} Visitor(Rec.ReferenceToConsteval);
18580	Visitor.TraverseStmt(
18581	S: Rec.ImmediateInvocationCandidates.front().getPointer()->getSubExpr());
18582	}
18583	for (auto CE : Rec.ImmediateInvocationCandidates)
18584	if (!CE.getInt())
18585	EvaluateAndDiagnoseImmediateInvocation(SemaRef, Candidate: CE);
18586	for (auto *DR : Rec.ReferenceToConsteval) {
18587	// If the expression is immediate escalating, it is not an error;
18588	// The outer context itself becomes immediate and further errors,
18589	// if any, will be handled by DiagnoseImmediateEscalatingReason.
18590	if (DR->isImmediateEscalating())
18591	continue;
18592	auto *FD = cast<FunctionDecl>(Val: DR->getDecl());
18593	const NamedDecl *ND = FD;
18594	if (const auto *MD = dyn_cast<CXXMethodDecl>(Val: ND);
18595	MD && (MD->isLambdaStaticInvoker() || isLambdaCallOperator(MD)))
18596	ND = MD->getParent();
18597
18598	// C++23 [expr.const]/p16
18599	// An expression or conversion is immediate-escalating if it is not
18600	// initially in an immediate function context and it is [...] a
18601	// potentially-evaluated id-expression that denotes an immediate function
18602	// that is not a subexpression of an immediate invocation.
18603	bool ImmediateEscalating = false;
18604	bool IsPotentiallyEvaluated =
18605	Rec.Context ==
18606	Sema::ExpressionEvaluationContext::PotentiallyEvaluated ||
18607	Rec.Context ==
18608	Sema::ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed;
18609	if (SemaRef.inTemplateInstantiation() && IsPotentiallyEvaluated)
18610	ImmediateEscalating = Rec.InImmediateEscalatingFunctionContext;
18611
18612	if (!Rec.InImmediateEscalatingFunctionContext ||
18613	(SemaRef.inTemplateInstantiation() && !ImmediateEscalating)) {
18614	SemaRef.Diag(DR->getBeginLoc(), diag::err_invalid_consteval_take_address)
18615	<< ND << isa<CXXRecordDecl>(ND) << FD->isConsteval();
18616	SemaRef.Diag(ND->getLocation(), diag::note_declared_at);
18617	if (auto Context =
18618	SemaRef.InnermostDeclarationWithDelayedImmediateInvocations()) {
18619	SemaRef.Diag(Context->Loc, diag::note_invalid_consteval_initializer)
18620	<< Context->Decl;
18621	SemaRef.Diag(Context->Decl->getBeginLoc(), diag::note_declared_at);
18622	}
18623	if (FD->isImmediateEscalating() && !FD->isConsteval())
18624	SemaRef.DiagnoseImmediateEscalatingReason(FD);
18625
18626	} else {
18627	SemaRef.MarkExpressionAsImmediateEscalating(DR);
18628	}
18629	}
18630	}
18631
18632	void Sema::PopExpressionEvaluationContext() {
18633	ExpressionEvaluationContextRecord& Rec = ExprEvalContexts.back();
18634	unsigned NumTypos = Rec.NumTypos;
18635
18636	if (!Rec.Lambdas.empty()) {
18637	using ExpressionKind = ExpressionEvaluationContextRecord::ExpressionKind;
18638	if (!getLangOpts().CPlusPlus20 &&
18639	(Rec.ExprContext == ExpressionKind::EK_TemplateArgument ||
18640	Rec.isUnevaluated() ||
18641	(Rec.isConstantEvaluated() && !getLangOpts().CPlusPlus17))) {
18642	unsigned D;
18643	if (Rec.isUnevaluated()) {
18644	// C++11 [expr.prim.lambda]p2:
18645	// A lambda-expression shall not appear in an unevaluated operand
18646	// (Clause 5).
18647	D = diag::err_lambda_unevaluated_operand;
18648	} else if (Rec.isConstantEvaluated() && !getLangOpts().CPlusPlus17) {
18649	// C++1y [expr.const]p2:
18650	// A conditional-expression e is a core constant expression unless the
18651	// evaluation of e, following the rules of the abstract machine, would
18652	// evaluate [...] a lambda-expression.
18653	D = diag::err_lambda_in_constant_expression;
18654	} else if (Rec.ExprContext == ExpressionKind::EK_TemplateArgument) {
18655	// C++17 [expr.prim.lamda]p2:
18656	// A lambda-expression shall not appear [...] in a template-argument.
18657	D = diag::err_lambda_in_invalid_context;
18658	} else
18659	llvm_unreachable("Couldn't infer lambda error message.");
18660
18661	for (const auto *L : Rec.Lambdas)
18662	Diag(Loc: L->getBeginLoc(), DiagID: D);
18663	}
18664	}
18665
18666	// Append the collected materialized temporaries into previous context before
18667	// exit if the previous also is a lifetime extending context.
18668	auto &PrevRecord = ExprEvalContexts[ExprEvalContexts.size() - 2];
18669	if (getLangOpts().CPlusPlus23 && isInLifetimeExtendingContext() &&
18670	PrevRecord.InLifetimeExtendingContext && !ExprEvalContexts.empty()) {
18671	auto &PrevRecord = ExprEvalContexts[ExprEvalContexts.size() - 2];
18672	PrevRecord.ForRangeLifetimeExtendTemps.append(
18673	RHS: Rec.ForRangeLifetimeExtendTemps);
18674	}
18675
18676	WarnOnPendingNoDerefs(Rec);
18677	HandleImmediateInvocations(SemaRef&: *this, Rec);
18678
18679	// Warn on any volatile-qualified simple-assignments that are not discarded-
18680	// value expressions nor unevaluated operands (those cases get removed from
18681	// this list by CheckUnusedVolatileAssignment).
18682	for (auto *BO : Rec.VolatileAssignmentLHSs)
18683	Diag(BO->getBeginLoc(), diag::warn_deprecated_simple_assign_volatile)
18684	<< BO->getType();
18685
18686	// When are coming out of an unevaluated context, clear out any
18687	// temporaries that we may have created as part of the evaluation of
18688	// the expression in that context: they aren't relevant because they
18689	// will never be constructed.
18690	if (Rec.isUnevaluated() || Rec.isConstantEvaluated()) {
18691	ExprCleanupObjects.erase(CS: ExprCleanupObjects.begin() + Rec.NumCleanupObjects,
18692	CE: ExprCleanupObjects.end());
18693	Cleanup = Rec.ParentCleanup;
18694	CleanupVarDeclMarking();
18695	std::swap(LHS&: MaybeODRUseExprs, RHS&: Rec.SavedMaybeODRUseExprs);
18696	// Otherwise, merge the contexts together.
18697	} else {
18698	Cleanup.mergeFrom(Rhs: Rec.ParentCleanup);
18699	MaybeODRUseExprs.insert(Start: Rec.SavedMaybeODRUseExprs.begin(),
18700	End: Rec.SavedMaybeODRUseExprs.end());
18701	}
18702
18703	// Pop the current expression evaluation context off the stack.
18704	ExprEvalContexts.pop_back();
18705
18706	// The global expression evaluation context record is never popped.
18707	ExprEvalContexts.back().NumTypos += NumTypos;
18708	}
18709
18710	void Sema::DiscardCleanupsInEvaluationContext() {
18711	ExprCleanupObjects.erase(
18712	CS: ExprCleanupObjects.begin() + ExprEvalContexts.back().NumCleanupObjects,
18713	CE: ExprCleanupObjects.end());
18714	Cleanup.reset();
18715	MaybeODRUseExprs.clear();
18716	}
18717
18718	ExprResult Sema::HandleExprEvaluationContextForTypeof(Expr *E) {
18719	ExprResult Result = CheckPlaceholderExpr(E);
18720	if (Result.isInvalid())
18721	return ExprError();
18722	E = Result.get();
18723	if (!E->getType()->isVariablyModifiedType())
18724	return E;
18725	return TransformToPotentiallyEvaluated(E);
18726	}
18727
18728	/// Are we in a context that is potentially constant evaluated per C++20
18729	/// [expr.const]p12?
18730	static bool isPotentiallyConstantEvaluatedContext(Sema &SemaRef) {
18731	/// C++2a [expr.const]p12:
18732	// An expression or conversion is potentially constant evaluated if it is
18733	switch (SemaRef.ExprEvalContexts.back().Context) {
18734	case Sema::ExpressionEvaluationContext::ConstantEvaluated:
18735	case Sema::ExpressionEvaluationContext::ImmediateFunctionContext:
18736
18737	// -- a manifestly constant-evaluated expression,
18738	case Sema::ExpressionEvaluationContext::PotentiallyEvaluated:
18739	case Sema::ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
18740	case Sema::ExpressionEvaluationContext::DiscardedStatement:
18741	// -- a potentially-evaluated expression,
18742	case Sema::ExpressionEvaluationContext::UnevaluatedList:
18743	// -- an immediate subexpression of a braced-init-list,
18744
18745	// -- [FIXME] an expression of the form & cast-expression that occurs
18746	// within a templated entity
18747	// -- a subexpression of one of the above that is not a subexpression of
18748	// a nested unevaluated operand.
18749	return true;
18750
18751	case Sema::ExpressionEvaluationContext::Unevaluated:
18752	case Sema::ExpressionEvaluationContext::UnevaluatedAbstract:
18753	// Expressions in this context are never evaluated.
18754	return false;
18755	}
18756	llvm_unreachable("Invalid context");
18757	}
18758
18759	/// Return true if this function has a calling convention that requires mangling
18760	/// in the size of the parameter pack.
18761	static bool funcHasParameterSizeMangling(Sema &S, FunctionDecl *FD) {
18762	// These manglings don't do anything on non-Windows or non-x86 platforms, so
18763	// we don't need parameter type sizes.
18764	const llvm::Triple &TT = S.Context.getTargetInfo().getTriple();
18765	if (!TT.isOSWindows() || !TT.isX86())
18766	return false;
18767
18768	// If this is C++ and this isn't an extern "C" function, parameters do not
18769	// need to be complete. In this case, C++ mangling will apply, which doesn't
18770	// use the size of the parameters.
18771	if (S.getLangOpts().CPlusPlus && !FD->isExternC())
18772	return false;
18773
18774	// Stdcall, fastcall, and vectorcall need this special treatment.
18775	CallingConv CC = FD->getType()->castAs<FunctionType>()->getCallConv();
18776	switch (CC) {
18777	case CC_X86StdCall:
18778	case CC_X86FastCall:
18779	case CC_X86VectorCall:
18780	return true;
18781	default:
18782	break;
18783	}
18784	return false;
18785	}
18786
18787	/// Require that all of the parameter types of function be complete. Normally,
18788	/// parameter types are only required to be complete when a function is called
18789	/// or defined, but to mangle functions with certain calling conventions, the
18790	/// mangler needs to know the size of the parameter list. In this situation,
18791	/// MSVC doesn't emit an error or instantiate templates. Instead, MSVC mangles
18792	/// the function as _foo@0, i.e. zero bytes of parameters, which will usually
18793	/// result in a linker error. Clang doesn't implement this behavior, and instead
18794	/// attempts to error at compile time.
18795	static void CheckCompleteParameterTypesForMangler(Sema &S, FunctionDecl *FD,
18796	SourceLocation Loc) {
18797	class ParamIncompleteTypeDiagnoser : public Sema::TypeDiagnoser {
18798	FunctionDecl *FD;
18799	ParmVarDecl *Param;
18800
18801	public:
18802	ParamIncompleteTypeDiagnoser(FunctionDecl *FD, ParmVarDecl *Param)
18803	: FD(FD), Param(Param) {}
18804
18805	void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
18806	CallingConv CC = FD->getType()->castAs<FunctionType>()->getCallConv();
18807	StringRef CCName;
18808	switch (CC) {
18809	case CC_X86StdCall:
18810	CCName = "stdcall";
18811	break;
18812	case CC_X86FastCall:
18813	CCName = "fastcall";
18814	break;
18815	case CC_X86VectorCall:
18816	CCName = "vectorcall";
18817	break;
18818	default:
18819	llvm_unreachable("CC does not need mangling");
18820	}
18821
18822	S.Diag(Loc, diag::err_cconv_incomplete_param_type)
18823	<< Param->getDeclName() << FD->getDeclName() << CCName;
18824	}
18825	};
18826
18827	for (ParmVarDecl *Param : FD->parameters()) {
18828	ParamIncompleteTypeDiagnoser Diagnoser(FD, Param);
18829	S.RequireCompleteType(Loc, Param->getType(), Diagnoser);
18830	}
18831	}
18832
18833	namespace {
18834	enum class OdrUseContext {
18835	/// Declarations in this context are not odr-used.
18836	None,
18837	/// Declarations in this context are formally odr-used, but this is a
18838	/// dependent context.
18839	Dependent,
18840	/// Declarations in this context are odr-used but not actually used (yet).
18841	FormallyOdrUsed,
18842	/// Declarations in this context are used.
18843	Used
18844	};
18845	}
18846
18847	/// Are we within a context in which references to resolved functions or to
18848	/// variables result in odr-use?
18849	static OdrUseContext isOdrUseContext(Sema &SemaRef) {
18850	OdrUseContext Result;
18851
18852	switch (SemaRef.ExprEvalContexts.back().Context) {
18853	case Sema::ExpressionEvaluationContext::Unevaluated:
18854	case Sema::ExpressionEvaluationContext::UnevaluatedList:
18855	case Sema::ExpressionEvaluationContext::UnevaluatedAbstract:
18856	return OdrUseContext::None;
18857
18858	case Sema::ExpressionEvaluationContext::ConstantEvaluated:
18859	case Sema::ExpressionEvaluationContext::ImmediateFunctionContext:
18860	case Sema::ExpressionEvaluationContext::PotentiallyEvaluated:
18861	Result = OdrUseContext::Used;
18862	break;
18863
18864	case Sema::ExpressionEvaluationContext::DiscardedStatement:
18865	Result = OdrUseContext::FormallyOdrUsed;
18866	break;
18867
18868	case Sema::ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
18869	// A default argument formally results in odr-use, but doesn't actually
18870	// result in a use in any real sense until it itself is used.
18871	Result = OdrUseContext::FormallyOdrUsed;
18872	break;
18873	}
18874
18875	if (SemaRef.CurContext->isDependentContext())
18876	return OdrUseContext::Dependent;
18877
18878	return Result;
18879	}
18880
18881	static bool isImplicitlyDefinableConstexprFunction(FunctionDecl *Func) {
18882	if (!Func->isConstexpr())
18883	return false;
18884
18885	if (Func->isImplicitlyInstantiable() || !Func->isUserProvided())
18886	return true;
18887	auto *CCD = dyn_cast<CXXConstructorDecl>(Val: Func);
18888	return CCD && CCD->getInheritedConstructor();
18889	}
18890
18891	/// Mark a function referenced, and check whether it is odr-used
18892	/// (C++ [basic.def.odr]p2, C99 6.9p3)
18893	void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func,
18894	bool MightBeOdrUse) {
18895	assert(Func && "No function?");
18896
18897	Func->setReferenced();
18898
18899	// Recursive functions aren't really used until they're used from some other
18900	// context.
18901	bool IsRecursiveCall = CurContext == Func;
18902
18903	// C++11 [basic.def.odr]p3:
18904	// A function whose name appears as a potentially-evaluated expression is
18905	// odr-used if it is the unique lookup result or the selected member of a
18906	// set of overloaded functions [...].
18907	//
18908	// We (incorrectly) mark overload resolution as an unevaluated context, so we
18909	// can just check that here.
18910	OdrUseContext OdrUse =
18911	MightBeOdrUse ? isOdrUseContext(SemaRef&: *this) : OdrUseContext::None;
18912	if (IsRecursiveCall && OdrUse == OdrUseContext::Used)
18913	OdrUse = OdrUseContext::FormallyOdrUsed;
18914
18915	// Trivial default constructors and destructors are never actually used.
18916	// FIXME: What about other special members?
18917	if (Func->isTrivial() && !Func->hasAttr<DLLExportAttr>() &&
18918	OdrUse == OdrUseContext::Used) {
18919	if (auto *Constructor = dyn_cast<CXXConstructorDecl>(Val: Func))
18920	if (Constructor->isDefaultConstructor())
18921	OdrUse = OdrUseContext::FormallyOdrUsed;
18922	if (isa<CXXDestructorDecl>(Val: Func))
18923	OdrUse = OdrUseContext::FormallyOdrUsed;
18924	}
18925
18926	// C++20 [expr.const]p12:
18927	// A function [...] is needed for constant evaluation if it is [...] a
18928	// constexpr function that is named by an expression that is potentially
18929	// constant evaluated
18930	bool NeededForConstantEvaluation =
18931	isPotentiallyConstantEvaluatedContext(SemaRef&: *this) &&
18932	isImplicitlyDefinableConstexprFunction(Func);
18933
18934	// Determine whether we require a function definition to exist, per
18935	// C++11 [temp.inst]p3:
18936	// Unless a function template specialization has been explicitly
18937	// instantiated or explicitly specialized, the function template
18938	// specialization is implicitly instantiated when the specialization is
18939	// referenced in a context that requires a function definition to exist.
18940	// C++20 [temp.inst]p7:
18941	// The existence of a definition of a [...] function is considered to
18942	// affect the semantics of the program if the [...] function is needed for
18943	// constant evaluation by an expression
18944	// C++20 [basic.def.odr]p10:
18945	// Every program shall contain exactly one definition of every non-inline
18946	// function or variable that is odr-used in that program outside of a
18947	// discarded statement
18948	// C++20 [special]p1:
18949	// The implementation will implicitly define [defaulted special members]
18950	// if they are odr-used or needed for constant evaluation.
18951	//
18952	// Note that we skip the implicit instantiation of templates that are only
18953	// used in unused default arguments or by recursive calls to themselves.
18954	// This is formally non-conforming, but seems reasonable in practice.
18955	bool NeedDefinition = !IsRecursiveCall && (OdrUse == OdrUseContext::Used ||
18956	NeededForConstantEvaluation);
18957
18958	// C++14 [temp.expl.spec]p6:
18959	// If a template [...] is explicitly specialized then that specialization
18960	// shall be declared before the first use of that specialization that would
18961	// cause an implicit instantiation to take place, in every translation unit
18962	// in which such a use occurs
18963	if (NeedDefinition &&
18964	(Func->getTemplateSpecializationKind() != TSK_Undeclared ||
18965	Func->getMemberSpecializationInfo()))
18966	checkSpecializationReachability(Loc, Func);
18967
18968	if (getLangOpts().CUDA)
18969	CheckCUDACall(Loc, Callee: Func);
18970
18971	// If we need a definition, try to create one.
18972	if (NeedDefinition && !Func->getBody()) {
18973	runWithSufficientStackSpace(Loc, Fn: [&] {
18974	if (CXXConstructorDecl *Constructor =
18975	dyn_cast<CXXConstructorDecl>(Val: Func)) {
18976	Constructor = cast<CXXConstructorDecl>(Constructor->getFirstDecl());
18977	if (Constructor->isDefaulted() && !Constructor->isDeleted()) {
18978	if (Constructor->isDefaultConstructor()) {
18979	if (Constructor->isTrivial() &&
18980	!Constructor->hasAttr<DLLExportAttr>())
18981	return;
18982	DefineImplicitDefaultConstructor(CurrentLocation: Loc, Constructor);
18983	} else if (Constructor->isCopyConstructor()) {
18984	DefineImplicitCopyConstructor(CurrentLocation: Loc, Constructor);
18985	} else if (Constructor->isMoveConstructor()) {
18986	DefineImplicitMoveConstructor(CurrentLocation: Loc, Constructor);
18987	}
18988	} else if (Constructor->getInheritedConstructor()) {
18989	DefineInheritingConstructor(UseLoc: Loc, Constructor);
18990	}
18991	} else if (CXXDestructorDecl *Destructor =
18992	dyn_cast<CXXDestructorDecl>(Val: Func)) {
18993	Destructor = cast<CXXDestructorDecl>(Destructor->getFirstDecl());
18994	if (Destructor->isDefaulted() && !Destructor->isDeleted()) {
18995	if (Destructor->isTrivial() && !Destructor->hasAttr<DLLExportAttr>())
18996	return;
18997	DefineImplicitDestructor(CurrentLocation: Loc, Destructor);
18998	}
18999	if (Destructor->isVirtual() && getLangOpts().AppleKext)
19000	MarkVTableUsed(Loc, Class: Destructor->getParent());
19001	} else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(Val: Func)) {
19002	if (MethodDecl->isOverloadedOperator() &&
19003	MethodDecl->getOverloadedOperator() == OO_Equal) {
19004	MethodDecl = cast<CXXMethodDecl>(MethodDecl->getFirstDecl());
19005	if (MethodDecl->isDefaulted() && !MethodDecl->isDeleted()) {
19006	if (MethodDecl->isCopyAssignmentOperator())
19007	DefineImplicitCopyAssignment(CurrentLocation: Loc, MethodDecl);
19008	else if (MethodDecl->isMoveAssignmentOperator())
19009	DefineImplicitMoveAssignment(CurrentLocation: Loc, MethodDecl);
19010	}
19011	} else if (isa<CXXConversionDecl>(Val: MethodDecl) &&
19012	MethodDecl->getParent()->isLambda()) {
19013	CXXConversionDecl *Conversion =
19014	cast<CXXConversionDecl>(MethodDecl->getFirstDecl());
19015	if (Conversion->isLambdaToBlockPointerConversion())
19016	DefineImplicitLambdaToBlockPointerConversion(CurrentLoc: Loc, Conv: Conversion);
19017	else
19018	DefineImplicitLambdaToFunctionPointerConversion(CurrentLoc: Loc, Conv: Conversion);
19019	} else if (MethodDecl->isVirtual() && getLangOpts().AppleKext)
19020	MarkVTableUsed(Loc, Class: MethodDecl->getParent());
19021	}
19022
19023	if (Func->isDefaulted() && !Func->isDeleted()) {
19024	DefaultedComparisonKind DCK = getDefaultedComparisonKind(FD: Func);
19025	if (DCK != DefaultedComparisonKind::None)
19026	DefineDefaultedComparison(Loc, FD: Func, DCK);
19027	}
19028
19029	// Implicit instantiation of function templates and member functions of
19030	// class templates.
19031	if (Func->isImplicitlyInstantiable()) {
19032	TemplateSpecializationKind TSK =
19033	Func->getTemplateSpecializationKindForInstantiation();
19034	SourceLocation PointOfInstantiation = Func->getPointOfInstantiation();
19035	bool FirstInstantiation = PointOfInstantiation.isInvalid();
19036	if (FirstInstantiation) {
19037	PointOfInstantiation = Loc;
19038	if (auto *MSI = Func->getMemberSpecializationInfo())
19039	MSI->setPointOfInstantiation(Loc);
19040	// FIXME: Notify listener.
19041	else
19042	Func->setTemplateSpecializationKind(TSK, PointOfInstantiation);
19043	} else if (TSK != TSK_ImplicitInstantiation) {
19044	// Use the point of use as the point of instantiation, instead of the
19045	// point of explicit instantiation (which we track as the actual point
19046	// of instantiation). This gives better backtraces in diagnostics.
19047	PointOfInstantiation = Loc;
19048	}
19049
19050	if (FirstInstantiation || TSK != TSK_ImplicitInstantiation ||
19051	Func->isConstexpr()) {
19052	if (isa<CXXRecordDecl>(Func->getDeclContext()) &&
19053	cast<CXXRecordDecl>(Func->getDeclContext())->isLocalClass() &&
19054	CodeSynthesisContexts.size())
19055	PendingLocalImplicitInstantiations.push_back(
19056	std::make_pair(x&: Func, y&: PointOfInstantiation));
19057	else if (Func->isConstexpr())
19058	// Do not defer instantiations of constexpr functions, to avoid the
19059	// expression evaluator needing to call back into Sema if it sees a
19060	// call to such a function.
19061	InstantiateFunctionDefinition(PointOfInstantiation, Function: Func);
19062	else {
19063	Func->setInstantiationIsPending(true);
19064	PendingInstantiations.push_back(
19065	std::make_pair(x&: Func, y&: PointOfInstantiation));
19066	// Notify the consumer that a function was implicitly instantiated.
19067	Consumer.HandleCXXImplicitFunctionInstantiation(D: Func);
19068	}
19069	}
19070	} else {
19071	// Walk redefinitions, as some of them may be instantiable.
19072	for (auto *i : Func->redecls()) {
19073	if (!i->isUsed(false) && i->isImplicitlyInstantiable())
19074	MarkFunctionReferenced(Loc, i, MightBeOdrUse);
19075	}
19076	}
19077	});
19078	}
19079
19080	// If a constructor was defined in the context of a default parameter
19081	// or of another default member initializer (ie a PotentiallyEvaluatedIfUsed
19082	// context), its initializers may not be referenced yet.
19083	if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Val: Func)) {
19084	EnterExpressionEvaluationContext EvalContext(
19085	*this,
19086	Constructor->isImmediateFunction()
19087	? ExpressionEvaluationContext::ImmediateFunctionContext
19088	: ExpressionEvaluationContext::PotentiallyEvaluated,
19089	Constructor);
19090	for (CXXCtorInitializer *Init : Constructor->inits()) {
19091	if (Init->isInClassMemberInitializer())
19092	runWithSufficientStackSpace(Loc: Init->getSourceLocation(), Fn: [&]() {
19093	MarkDeclarationsReferencedInExpr(E: Init->getInit());
19094	});
19095	}
19096	}
19097
19098	// C++14 [except.spec]p17:
19099	// An exception-specification is considered to be needed when:
19100	// - the function is odr-used or, if it appears in an unevaluated operand,
19101	// would be odr-used if the expression were potentially-evaluated;
19102	//
19103	// Note, we do this even if MightBeOdrUse is false. That indicates that the
19104	// function is a pure virtual function we're calling, and in that case the
19105	// function was selected by overload resolution and we need to resolve its
19106	// exception specification for a different reason.
19107	const FunctionProtoType *FPT = Func->getType()->getAs<FunctionProtoType>();
19108	if (FPT && isUnresolvedExceptionSpec(ESpecType: FPT->getExceptionSpecType()))
19109	ResolveExceptionSpec(Loc, FPT);
19110
19111	// A callee could be called by a host function then by a device function.
19112	// If we only try recording once, we will miss recording the use on device
19113	// side. Therefore keep trying until it is recorded.
19114	if (LangOpts.OffloadImplicitHostDeviceTemplates && LangOpts.CUDAIsDevice &&
19115	!getASTContext().CUDAImplicitHostDeviceFunUsedByDevice.count(V: Func))
19116	CUDARecordImplicitHostDeviceFuncUsedByDevice(FD: Func);
19117
19118	// If this is the first "real" use, act on that.
19119	if (OdrUse == OdrUseContext::Used && !Func->isUsed(/*CheckUsedAttr=*/false)) {
19120	// Keep track of used but undefined functions.
19121	if (!Func->isDefined()) {
19122	if (mightHaveNonExternalLinkage(Func))
19123	UndefinedButUsed.insert(std::make_pair(x: Func->getCanonicalDecl(), y&: Loc));
19124	else if (Func->getMostRecentDecl()->isInlined() &&
19125	!LangOpts.GNUInline &&
19126	!Func->getMostRecentDecl()->hasAttr<GNUInlineAttr>())
19127	UndefinedButUsed.insert(std::make_pair(x: Func->getCanonicalDecl(), y&: Loc));
19128	else if (isExternalWithNoLinkageType(Func))
19129	UndefinedButUsed.insert(std::make_pair(x: Func->getCanonicalDecl(), y&: Loc));
19130	}
19131
19132	// Some x86 Windows calling conventions mangle the size of the parameter
19133	// pack into the name. Computing the size of the parameters requires the
19134	// parameter types to be complete. Check that now.
19135	if (funcHasParameterSizeMangling(S&: *this, FD: Func))
19136	CheckCompleteParameterTypesForMangler(S&: *this, FD: Func, Loc);
19137
19138	// In the MS C++ ABI, the compiler emits destructor variants where they are
19139	// used. If the destructor is used here but defined elsewhere, mark the
19140	// virtual base destructors referenced. If those virtual base destructors
19141	// are inline, this will ensure they are defined when emitting the complete
19142	// destructor variant. This checking may be redundant if the destructor is
19143	// provided later in this TU.
19144	if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
19145	if (auto *Dtor = dyn_cast<CXXDestructorDecl>(Val: Func)) {
19146	CXXRecordDecl *Parent = Dtor->getParent();
19147	if (Parent->getNumVBases() > 0 && !Dtor->getBody())
19148	CheckCompleteDestructorVariant(CurrentLocation: Loc, Dtor);
19149	}
19150	}
19151
19152	Func->markUsed(Context);
19153	}
19154	}
19155
19156	/// Directly mark a variable odr-used. Given a choice, prefer to use
19157	/// MarkVariableReferenced since it does additional checks and then
19158	/// calls MarkVarDeclODRUsed.
19159	/// If the variable must be captured:
19160	/// - if FunctionScopeIndexToStopAt is null, capture it in the CurContext
19161	/// - else capture it in the DeclContext that maps to the
19162	/// *FunctionScopeIndexToStopAt on the FunctionScopeInfo stack.
19163	static void
19164	MarkVarDeclODRUsed(ValueDecl *V, SourceLocation Loc, Sema &SemaRef,
19165	const unsigned *const FunctionScopeIndexToStopAt = nullptr) {
19166	// Keep track of used but undefined variables.
19167	// FIXME: We shouldn't suppress this warning for static data members.
19168	VarDecl *Var = V->getPotentiallyDecomposedVarDecl();
19169	assert(Var && "expected a capturable variable");
19170
19171	if (Var->hasDefinition(SemaRef.Context) == VarDecl::DeclarationOnly &&
19172	(!Var->isExternallyVisible() || Var->isInline() ||
19173	SemaRef.isExternalWithNoLinkageType(Var)) &&
19174	!(Var->isStaticDataMember() && Var->hasInit())) {
19175	SourceLocation &old = SemaRef.UndefinedButUsed[Var->getCanonicalDecl()];
19176	if (old.isInvalid())
19177	old = Loc;
19178	}
19179	QualType CaptureType, DeclRefType;
19180	if (SemaRef.LangOpts.OpenMP)
19181	SemaRef.tryCaptureOpenMPLambdas(V);
19182	SemaRef.tryCaptureVariable(Var: V, Loc, Kind: Sema::TryCapture_Implicit,
19183	/*EllipsisLoc*/ SourceLocation(),
19184	/*BuildAndDiagnose*/ true, CaptureType,
19185	DeclRefType, FunctionScopeIndexToStopAt);
19186
19187	if (SemaRef.LangOpts.CUDA && Var->hasGlobalStorage()) {
19188	auto *FD = dyn_cast_or_null<FunctionDecl>(Val: SemaRef.CurContext);
19189	auto VarTarget = SemaRef.IdentifyCUDATarget(D: Var);
19190	auto UserTarget = SemaRef.IdentifyCUDATarget(D: FD);
19191	if (VarTarget == Sema::CVT_Host &&
19192	(UserTarget == Sema::CFT_Device || UserTarget == Sema::CFT_HostDevice ||
19193	UserTarget == Sema::CFT_Global)) {
19194	// Diagnose ODR-use of host global variables in device functions.
19195	// Reference of device global variables in host functions is allowed
19196	// through shadow variables therefore it is not diagnosed.
19197	if (SemaRef.LangOpts.CUDAIsDevice && !SemaRef.LangOpts.HIPStdPar) {
19198	SemaRef.targetDiag(Loc, diag::err_ref_bad_target)
19199	<< /*host*/ 2 << /*variable*/ 1 << Var << UserTarget;
19200	SemaRef.targetDiag(Var->getLocation(),
19201	Var->getType().isConstQualified()
19202	? diag::note_cuda_const_var_unpromoted
19203	: diag::note_cuda_host_var);
19204	}
19205	} else if (VarTarget == Sema::CVT_Device &&
19206	!Var->hasAttr<CUDASharedAttr>() &&
19207	(UserTarget == Sema::CFT_Host ||
19208	UserTarget == Sema::CFT_HostDevice)) {
19209	// Record a CUDA/HIP device side variable if it is ODR-used
19210	// by host code. This is done conservatively, when the variable is
19211	// referenced in any of the following contexts:
19212	// - a non-function context
19213	// - a host function
19214	// - a host device function
19215	// This makes the ODR-use of the device side variable by host code to
19216	// be visible in the device compilation for the compiler to be able to
19217	// emit template variables instantiated by host code only and to
19218	// externalize the static device side variable ODR-used by host code.
19219	if (!Var->hasExternalStorage())
19220	SemaRef.getASTContext().CUDADeviceVarODRUsedByHost.insert(V: Var);
19221	else if (SemaRef.LangOpts.GPURelocatableDeviceCode)
19222	SemaRef.getASTContext().CUDAExternalDeviceDeclODRUsedByHost.insert(Var);
19223	}
19224	}
19225
19226	V->markUsed(SemaRef.Context);
19227	}
19228
19229	void Sema::MarkCaptureUsedInEnclosingContext(ValueDecl *Capture,
19230	SourceLocation Loc,
19231	unsigned CapturingScopeIndex) {
19232	MarkVarDeclODRUsed(V: Capture, Loc, SemaRef&: *this, FunctionScopeIndexToStopAt: &CapturingScopeIndex);
19233	}
19234
19235	void diagnoseUncapturableValueReferenceOrBinding(Sema &S, SourceLocation loc,
19236	ValueDecl *var) {
19237	DeclContext *VarDC = var->getDeclContext();
19238
19239	// If the parameter still belongs to the translation unit, then
19240	// we're actually just using one parameter in the declaration of
19241	// the next.
19242	if (isa<ParmVarDecl>(Val: var) &&
19243	isa<TranslationUnitDecl>(Val: VarDC))
19244	return;
19245
19246	// For C code, don't diagnose about capture if we're not actually in code
19247	// right now; it's impossible to write a non-constant expression outside of
19248	// function context, so we'll get other (more useful) diagnostics later.
19249	//
19250	// For C++, things get a bit more nasty... it would be nice to suppress this
19251	// diagnostic for certain cases like using a local variable in an array bound
19252	// for a member of a local class, but the correct predicate is not obvious.
19253	if (!S.getLangOpts().CPlusPlus && !S.CurContext->isFunctionOrMethod())
19254	return;
19255
19256	unsigned ValueKind = isa<BindingDecl>(Val: var) ? 1 : 0;
19257	unsigned ContextKind = 3; // unknown
19258	if (isa<CXXMethodDecl>(Val: VarDC) &&
19259	cast<CXXRecordDecl>(Val: VarDC->getParent())->isLambda()) {
19260	ContextKind = 2;
19261	} else if (isa<FunctionDecl>(Val: VarDC)) {
19262	ContextKind = 0;
19263	} else if (isa<BlockDecl>(Val: VarDC)) {
19264	ContextKind = 1;
19265	}
19266
19267	S.Diag(loc, diag::err_reference_to_local_in_enclosing_context)
19268	<< var << ValueKind << ContextKind << VarDC;
19269	S.Diag(var->getLocation(), diag::note_entity_declared_at)
19270	<< var;
19271
19272	// FIXME: Add additional diagnostic info about class etc. which prevents
19273	// capture.
19274	}
19275
19276	static bool isVariableAlreadyCapturedInScopeInfo(CapturingScopeInfo *CSI,
19277	ValueDecl *Var,
19278	bool &SubCapturesAreNested,
19279	QualType &CaptureType,
19280	QualType &DeclRefType) {
19281	// Check whether we've already captured it.
19282	if (CSI->CaptureMap.count(Val: Var)) {
19283	// If we found a capture, any subcaptures are nested.
19284	SubCapturesAreNested = true;
19285
19286	// Retrieve the capture type for this variable.
19287	CaptureType = CSI->getCapture(Var).getCaptureType();
19288
19289	// Compute the type of an expression that refers to this variable.
19290	DeclRefType = CaptureType.getNonReferenceType();
19291
19292	// Similarly to mutable captures in lambda, all the OpenMP captures by copy
19293	// are mutable in the sense that user can change their value - they are
19294	// private instances of the captured declarations.
19295	const Capture &Cap = CSI->getCapture(Var);
19296	if (Cap.isCopyCapture() &&
19297	!(isa<LambdaScopeInfo>(Val: CSI) &&
19298	!cast<LambdaScopeInfo>(Val: CSI)->lambdaCaptureShouldBeConst()) &&
19299	!(isa<CapturedRegionScopeInfo>(Val: CSI) &&
19300	cast<CapturedRegionScopeInfo>(Val: CSI)->CapRegionKind == CR_OpenMP))
19301	DeclRefType.addConst();
19302	return true;
19303	}
19304	return false;
19305	}
19306
19307	// Only block literals, captured statements, and lambda expressions can
19308	// capture; other scopes don't work.
19309	static DeclContext *getParentOfCapturingContextOrNull(DeclContext *DC,
19310	ValueDecl *Var,
19311	SourceLocation Loc,
19312	const bool Diagnose,
19313	Sema &S) {
19314	if (isa<BlockDecl>(Val: DC) || isa<CapturedDecl>(Val: DC) || isLambdaCallOperator(DC))
19315	return getLambdaAwareParentOfDeclContext(DC);
19316
19317	VarDecl *Underlying = Var->getPotentiallyDecomposedVarDecl();
19318	if (Underlying) {
19319	if (Underlying->hasLocalStorage() && Diagnose)
19320	diagnoseUncapturableValueReferenceOrBinding(S, loc: Loc, var: Var);
19321	}
19322	return nullptr;
19323	}
19324
19325	// Certain capturing entities (lambdas, blocks etc.) are not allowed to capture
19326	// certain types of variables (unnamed, variably modified types etc.)
19327	// so check for eligibility.
19328	static bool isVariableCapturable(CapturingScopeInfo *CSI, ValueDecl *Var,
19329	SourceLocation Loc, const bool Diagnose,
19330	Sema &S) {
19331
19332	assert((isa<VarDecl, BindingDecl>(Var)) &&
19333	"Only variables and structured bindings can be captured");
19334
19335	bool IsBlock = isa<BlockScopeInfo>(Val: CSI);
19336	bool IsLambda = isa<LambdaScopeInfo>(Val: CSI);
19337
19338	// Lambdas are not allowed to capture unnamed variables
19339	// (e.g. anonymous unions).
19340	// FIXME: The C++11 rule don't actually state this explicitly, but I'm
19341	// assuming that's the intent.
19342	if (IsLambda && !Var->getDeclName()) {
19343	if (Diagnose) {
19344	S.Diag(Loc, diag::err_lambda_capture_anonymous_var);
19345	S.Diag(Var->getLocation(), diag::note_declared_at);
19346	}
19347	return false;
19348	}
19349
19350	// Prohibit variably-modified types in blocks; they're difficult to deal with.
19351	if (Var->getType()->isVariablyModifiedType() && IsBlock) {
19352	if (Diagnose) {
19353	S.Diag(Loc, diag::err_ref_vm_type);
19354	S.Diag(Var->getLocation(), diag::note_previous_decl) << Var;
19355	}
19356	return false;
19357	}
19358	// Prohibit structs with flexible array members too.
19359	// We cannot capture what is in the tail end of the struct.
19360	if (const RecordType *VTTy = Var->getType()->getAs<RecordType>()) {
19361	if (VTTy->getDecl()->hasFlexibleArrayMember()) {
19362	if (Diagnose) {
19363	if (IsBlock)
19364	S.Diag(Loc, diag::err_ref_flexarray_type);
19365	else
19366	S.Diag(Loc, diag::err_lambda_capture_flexarray_type) << Var;
19367	S.Diag(Var->getLocation(), diag::note_previous_decl) << Var;
19368	}
19369	return false;
19370	}
19371	}
19372	const bool HasBlocksAttr = Var->hasAttr<BlocksAttr>();
19373	// Lambdas and captured statements are not allowed to capture __block
19374	// variables; they don't support the expected semantics.
19375	if (HasBlocksAttr && (IsLambda || isa<CapturedRegionScopeInfo>(Val: CSI))) {
19376	if (Diagnose) {
19377	S.Diag(Loc, diag::err_capture_block_variable) << Var << !IsLambda;
19378	S.Diag(Var->getLocation(), diag::note_previous_decl) << Var;
19379	}
19380	return false;
19381	}
19382	// OpenCL v2.0 s6.12.5: Blocks cannot reference/capture other blocks
19383	if (S.getLangOpts().OpenCL && IsBlock &&
19384	Var->getType()->isBlockPointerType()) {
19385	if (Diagnose)
19386	S.Diag(Loc, diag::err_opencl_block_ref_block);
19387	return false;
19388	}
19389
19390	if (isa<BindingDecl>(Val: Var)) {
19391	if (!IsLambda || !S.getLangOpts().CPlusPlus) {
19392	if (Diagnose)
19393	diagnoseUncapturableValueReferenceOrBinding(S, loc: Loc, var: Var);
19394	return false;
19395	} else if (Diagnose && S.getLangOpts().CPlusPlus) {
19396	S.Diag(Loc, S.LangOpts.CPlusPlus20
19397	? diag::warn_cxx17_compat_capture_binding
19398	: diag::ext_capture_binding)
19399	<< Var;
19400	S.Diag(Var->getLocation(), diag::note_entity_declared_at) << Var;
19401	}
19402	}
19403
19404	return true;
19405	}
19406
19407	// Returns true if the capture by block was successful.
19408	static bool captureInBlock(BlockScopeInfo *BSI, ValueDecl *Var,
19409	SourceLocation Loc, const bool BuildAndDiagnose,
19410	QualType &CaptureType, QualType &DeclRefType,
19411	const bool Nested, Sema &S, bool Invalid) {
19412	bool ByRef = false;
19413
19414	// Blocks are not allowed to capture arrays, excepting OpenCL.
19415	// OpenCL v2.0 s1.12.5 (revision 40): arrays are captured by reference
19416	// (decayed to pointers).
19417	if (!Invalid && !S.getLangOpts().OpenCL && CaptureType->isArrayType()) {
19418	if (BuildAndDiagnose) {
19419	S.Diag(Loc, diag::err_ref_array_type);
19420	S.Diag(Var->getLocation(), diag::note_previous_decl) << Var;
19421	Invalid = true;
19422	} else {
19423	return false;
19424	}
19425	}
19426
19427	// Forbid the block-capture of autoreleasing variables.
19428	if (!Invalid &&
19429	CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) {
19430	if (BuildAndDiagnose) {
19431	S.Diag(Loc, diag::err_arc_autoreleasing_capture)
19432	<< /*block*/ 0;
19433	S.Diag(Var->getLocation(), diag::note_previous_decl) << Var;
19434	Invalid = true;
19435	} else {
19436	return false;
19437	}
19438	}
19439
19440	// Warn about implicitly autoreleasing indirect parameters captured by blocks.
19441	if (const auto *PT = CaptureType->getAs<PointerType>()) {
19442	QualType PointeeTy = PT->getPointeeType();
19443
19444	if (!Invalid && PointeeTy->getAs<ObjCObjectPointerType>() &&
19445	PointeeTy.getObjCLifetime() == Qualifiers::OCL_Autoreleasing &&
19446	!S.Context.hasDirectOwnershipQualifier(Ty: PointeeTy)) {
19447	if (BuildAndDiagnose) {
19448	SourceLocation VarLoc = Var->getLocation();
19449	S.Diag(Loc, diag::warn_block_capture_autoreleasing);
19450	S.Diag(VarLoc, diag::note_declare_parameter_strong);
19451	}
19452	}
19453	}
19454
19455	const bool HasBlocksAttr = Var->hasAttr<BlocksAttr>();
19456	if (HasBlocksAttr || CaptureType->isReferenceType() ||
19457	(S.getLangOpts().OpenMP && S.isOpenMPCapturedDecl(D: Var))) {
19458	// Block capture by reference does not change the capture or
19459	// declaration reference types.
19460	ByRef = true;
19461	} else {
19462	// Block capture by copy introduces 'const'.
19463	CaptureType = CaptureType.getNonReferenceType().withConst();
19464	DeclRefType = CaptureType;
19465	}
19466
19467	// Actually capture the variable.
19468	if (BuildAndDiagnose)
19469	BSI->addCapture(Var, HasBlocksAttr, ByRef, Nested, Loc, SourceLocation(),
19470	CaptureType, Invalid);
19471
19472	return !Invalid;
19473	}
19474
19475	/// Capture the given variable in the captured region.
19476	static bool captureInCapturedRegion(
19477	CapturedRegionScopeInfo *RSI, ValueDecl *Var, SourceLocation Loc,
19478	const bool BuildAndDiagnose, QualType &CaptureType, QualType &DeclRefType,
19479	const bool RefersToCapturedVariable, Sema::TryCaptureKind Kind,
19480	bool IsTopScope, Sema &S, bool Invalid) {
19481	// By default, capture variables by reference.
19482	bool ByRef = true;
19483	if (IsTopScope && Kind != Sema::TryCapture_Implicit) {
19484	ByRef = (Kind == Sema::TryCapture_ExplicitByRef);
19485	} else if (S.getLangOpts().OpenMP && RSI->CapRegionKind == CR_OpenMP) {
19486	// Using an LValue reference type is consistent with Lambdas (see below).
19487	if (S.isOpenMPCapturedDecl(D: Var)) {
19488	bool HasConst = DeclRefType.isConstQualified();
19489	DeclRefType = DeclRefType.getUnqualifiedType();
19490	// Don't lose diagnostics about assignments to const.
19491	if (HasConst)
19492	DeclRefType.addConst();
19493	}
19494	// Do not capture firstprivates in tasks.
19495	if (S.isOpenMPPrivateDecl(Var, RSI->OpenMPLevel, RSI->OpenMPCaptureLevel) !=
19496	OMPC_unknown)
19497	return true;
19498	ByRef = S.isOpenMPCapturedByRef(D: Var, Level: RSI->OpenMPLevel,
19499	OpenMPCaptureLevel: RSI->OpenMPCaptureLevel);
19500	}
19501
19502	if (ByRef)
19503	CaptureType = S.Context.getLValueReferenceType(T: DeclRefType);
19504	else
19505	CaptureType = DeclRefType;
19506
19507	// Actually capture the variable.
19508	if (BuildAndDiagnose)
19509	RSI->addCapture(Var, /*isBlock*/ false, ByRef, RefersToCapturedVariable,
19510	Loc, SourceLocation(), CaptureType, Invalid);
19511
19512	return !Invalid;
19513	}
19514
19515	/// Capture the given variable in the lambda.
19516	static bool captureInLambda(LambdaScopeInfo *LSI, ValueDecl *Var,
19517	SourceLocation Loc, const bool BuildAndDiagnose,
19518	QualType &CaptureType, QualType &DeclRefType,
19519	const bool RefersToCapturedVariable,
19520	const Sema::TryCaptureKind Kind,
19521	SourceLocation EllipsisLoc, const bool IsTopScope,
19522	Sema &S, bool Invalid) {
19523	// Determine whether we are capturing by reference or by value.
19524	bool ByRef = false;
19525	if (IsTopScope && Kind != Sema::TryCapture_Implicit) {
19526	ByRef = (Kind == Sema::TryCapture_ExplicitByRef);
19527	} else {
19528	ByRef = (LSI->ImpCaptureStyle == LambdaScopeInfo::ImpCap_LambdaByref);
19529	}
19530
19531	if (BuildAndDiagnose && S.Context.getTargetInfo().getTriple().isWasm() &&
19532	CaptureType.getNonReferenceType().isWebAssemblyReferenceType()) {
19533	S.Diag(Loc, diag::err_wasm_ca_reference) << 0;
19534	Invalid = true;
19535	}
19536
19537	// Compute the type of the field that will capture this variable.
19538	if (ByRef) {
19539	// C++11 [expr.prim.lambda]p15:
19540	// An entity is captured by reference if it is implicitly or
19541	// explicitly captured but not captured by copy. It is
19542	// unspecified whether additional unnamed non-static data
19543	// members are declared in the closure type for entities
19544	// captured by reference.
19545	//
19546	// FIXME: It is not clear whether we want to build an lvalue reference
19547	// to the DeclRefType or to CaptureType.getNonReferenceType(). GCC appears
19548	// to do the former, while EDG does the latter. Core issue 1249 will
19549	// clarify, but for now we follow GCC because it's a more permissive and
19550	// easily defensible position.
19551	CaptureType = S.Context.getLValueReferenceType(T: DeclRefType);
19552	} else {
19553	// C++11 [expr.prim.lambda]p14:
19554	// For each entity captured by copy, an unnamed non-static
19555	// data member is declared in the closure type. The
19556	// declaration order of these members is unspecified. The type
19557	// of such a data member is the type of the corresponding
19558	// captured entity if the entity is not a reference to an
19559	// object, or the referenced type otherwise. [Note: If the
19560	// captured entity is a reference to a function, the
19561	// corresponding data member is also a reference to a
19562	// function. - end note ]
19563	if (const ReferenceType *RefType = CaptureType->getAs<ReferenceType>()){
19564	if (!RefType->getPointeeType()->isFunctionType())
19565	CaptureType = RefType->getPointeeType();
19566	}
19567
19568	// Forbid the lambda copy-capture of autoreleasing variables.
19569	if (!Invalid &&
19570	CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) {
19571	if (BuildAndDiagnose) {
19572	S.Diag(Loc, diag::err_arc_autoreleasing_capture) << /*lambda*/ 1;
19573	S.Diag(Var->getLocation(), diag::note_previous_decl)
19574	<< Var->getDeclName();
19575	Invalid = true;
19576	} else {
19577	return false;
19578	}
19579	}
19580
19581	// Make sure that by-copy captures are of a complete and non-abstract type.
19582	if (!Invalid && BuildAndDiagnose) {
19583	if (!CaptureType->isDependentType() &&
19584	S.RequireCompleteSizedType(
19585	Loc, CaptureType,
19586	diag::err_capture_of_incomplete_or_sizeless_type,
19587	Var->getDeclName()))
19588	Invalid = true;
19589	else if (S.RequireNonAbstractType(Loc, CaptureType,
19590	diag::err_capture_of_abstract_type))
19591	Invalid = true;
19592	}
19593	}
19594
19595	// Compute the type of a reference to this captured variable.
19596	if (ByRef)
19597	DeclRefType = CaptureType.getNonReferenceType();
19598	else {
19599	// C++ [expr.prim.lambda]p5:
19600	// The closure type for a lambda-expression has a public inline
19601	// function call operator [...]. This function call operator is
19602	// declared const (9.3.1) if and only if the lambda-expression's
19603	// parameter-declaration-clause is not followed by mutable.
19604	DeclRefType = CaptureType.getNonReferenceType();
19605	bool Const = LSI->lambdaCaptureShouldBeConst();
19606	if (Const && !CaptureType->isReferenceType())
19607	DeclRefType.addConst();
19608	}
19609
19610	// Add the capture.
19611	if (BuildAndDiagnose)
19612	LSI->addCapture(Var, /*isBlock=*/false, ByRef, RefersToCapturedVariable,
19613	Loc, EllipsisLoc, CaptureType, Invalid);
19614
19615	return !Invalid;
19616	}
19617
19618	static bool canCaptureVariableByCopy(ValueDecl *Var,
19619	const ASTContext &Context) {
19620	// Offer a Copy fix even if the type is dependent.
19621	if (Var->getType()->isDependentType())
19622	return true;
19623	QualType T = Var->getType().getNonReferenceType();
19624	if (T.isTriviallyCopyableType(Context))
19625	return true;
19626	if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
19627
19628	if (!(RD = RD->getDefinition()))
19629	return false;
19630	if (RD->hasSimpleCopyConstructor())
19631	return true;
19632	if (RD->hasUserDeclaredCopyConstructor())
19633	for (CXXConstructorDecl *Ctor : RD->ctors())
19634	if (Ctor->isCopyConstructor())
19635	return !Ctor->isDeleted();
19636	}
19637	return false;
19638	}
19639
19640	/// Create up to 4 fix-its for explicit reference and value capture of \p Var or
19641	/// default capture. Fixes may be omitted if they aren't allowed by the
19642	/// standard, for example we can't emit a default copy capture fix-it if we
19643	/// already explicitly copy capture capture another variable.
19644	static void buildLambdaCaptureFixit(Sema &Sema, LambdaScopeInfo *LSI,
19645	ValueDecl *Var) {
19646	assert(LSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None);
19647	// Don't offer Capture by copy of default capture by copy fixes if Var is
19648	// known not to be copy constructible.
19649	bool ShouldOfferCopyFix = canCaptureVariableByCopy(Var, Context: Sema.getASTContext());
19650
19651	SmallString<32> FixBuffer;
19652	StringRef Separator = LSI->NumExplicitCaptures > 0 ? ", " : "";
19653	if (Var->getDeclName().isIdentifier() && !Var->getName().empty()) {
19654	SourceLocation VarInsertLoc = LSI->IntroducerRange.getEnd();
19655	if (ShouldOfferCopyFix) {
19656	// Offer fixes to insert an explicit capture for the variable.
19657	// [] -> [VarName]
19658	// [OtherCapture] -> [OtherCapture, VarName]
19659	FixBuffer.assign({Separator, Var->getName()});
19660	Sema.Diag(VarInsertLoc, diag::note_lambda_variable_capture_fixit)
19661	<< Var << /*value*/ 0
19662	<< FixItHint::CreateInsertion(VarInsertLoc, FixBuffer);
19663	}
19664	// As above but capture by reference.
19665	FixBuffer.assign({Separator, "&", Var->getName()});
19666	Sema.Diag(VarInsertLoc, diag::note_lambda_variable_capture_fixit)
19667	<< Var << /*reference*/ 1
19668	<< FixItHint::CreateInsertion(VarInsertLoc, FixBuffer);
19669	}
19670
19671	// Only try to offer default capture if there are no captures excluding this
19672	// and init captures.
19673	// [this]: OK.
19674	// [X = Y]: OK.
19675	// [&A, &B]: Don't offer.
19676	// [A, B]: Don't offer.
19677	if (llvm::any_of(Range&: LSI->Captures, P: [](Capture &C) {
19678	return !C.isThisCapture() && !C.isInitCapture();
19679	}))
19680	return;
19681
19682	// The default capture specifiers, '=' or '&', must appear first in the
19683	// capture body.
19684	SourceLocation DefaultInsertLoc =
19685	LSI->IntroducerRange.getBegin().getLocWithOffset(Offset: 1);
19686
19687	if (ShouldOfferCopyFix) {
19688	bool CanDefaultCopyCapture = true;
19689	// [=, *this] OK since c++17
19690	// [=, this] OK since c++20
19691	if (LSI->isCXXThisCaptured() && !Sema.getLangOpts().CPlusPlus20)
19692	CanDefaultCopyCapture = Sema.getLangOpts().CPlusPlus17
19693	? LSI->getCXXThisCapture().isCopyCapture()
19694	: false;
19695	// We can't use default capture by copy if any captures already specified
19696	// capture by copy.
19697	if (CanDefaultCopyCapture && llvm::none_of(Range&: LSI->Captures, P: [](Capture &C) {
19698	return !C.isThisCapture() && !C.isInitCapture() && C.isCopyCapture();
19699	})) {
19700	FixBuffer.assign(Refs: {"=", Separator});
19701	Sema.Diag(DefaultInsertLoc, diag::note_lambda_default_capture_fixit)
19702	<< /*value*/ 0
19703	<< FixItHint::CreateInsertion(DefaultInsertLoc, FixBuffer);
19704	}
19705	}
19706
19707	// We can't use default capture by reference if any captures already specified
19708	// capture by reference.
19709	if (llvm::none_of(Range&: LSI->Captures, P: [](Capture &C) {
19710	return !C.isInitCapture() && C.isReferenceCapture() &&
19711	!C.isThisCapture();
19712	})) {
19713	FixBuffer.assign(Refs: {"&", Separator});
19714	Sema.Diag(DefaultInsertLoc, diag::note_lambda_default_capture_fixit)
19715	<< /*reference*/ 1
19716	<< FixItHint::CreateInsertion(DefaultInsertLoc, FixBuffer);
19717	}
19718	}
19719
19720	bool Sema::tryCaptureVariable(
19721	ValueDecl *Var, SourceLocation ExprLoc, TryCaptureKind Kind,
19722	SourceLocation EllipsisLoc, bool BuildAndDiagnose, QualType &CaptureType,
19723	QualType &DeclRefType, const unsigned *const FunctionScopeIndexToStopAt) {
19724	// An init-capture is notionally from the context surrounding its
19725	// declaration, but its parent DC is the lambda class.
19726	DeclContext *VarDC = Var->getDeclContext();
19727	DeclContext *DC = CurContext;
19728
19729	// tryCaptureVariable is called every time a DeclRef is formed,
19730	// it can therefore have non-negigible impact on performances.
19731	// For local variables and when there is no capturing scope,
19732	// we can bailout early.
19733	if (CapturingFunctionScopes == 0 && (!BuildAndDiagnose || VarDC == DC))
19734	return true;
19735
19736	const auto *VD = dyn_cast<VarDecl>(Val: Var);
19737	if (VD) {
19738	if (VD->isInitCapture())
19739	VarDC = VarDC->getParent();
19740	} else {
19741	VD = Var->getPotentiallyDecomposedVarDecl();
19742	}
19743	assert(VD && "Cannot capture a null variable");
19744
19745	const unsigned MaxFunctionScopesIndex = FunctionScopeIndexToStopAt
19746	? *FunctionScopeIndexToStopAt : FunctionScopes.size() - 1;
19747	// We need to sync up the Declaration Context with the
19748	// FunctionScopeIndexToStopAt
19749	if (FunctionScopeIndexToStopAt) {
19750	unsigned FSIndex = FunctionScopes.size() - 1;
19751	while (FSIndex != MaxFunctionScopesIndex) {
19752	DC = getLambdaAwareParentOfDeclContext(DC);
19753	--FSIndex;
19754	}
19755	}
19756
19757	// Capture global variables if it is required to use private copy of this
19758	// variable.
19759	bool IsGlobal = !VD->hasLocalStorage();
19760	if (IsGlobal &&
19761	!(LangOpts.OpenMP && isOpenMPCapturedDecl(D: Var, /*CheckScopeInfo=*/true,
19762	StopAt: MaxFunctionScopesIndex)))
19763	return true;
19764
19765	if (isa<VarDecl>(Val: Var))
19766	Var = cast<VarDecl>(Var->getCanonicalDecl());
19767
19768	// Walk up the stack to determine whether we can capture the variable,
19769	// performing the "simple" checks that don't depend on type. We stop when
19770	// we've either hit the declared scope of the variable or find an existing
19771	// capture of that variable. We start from the innermost capturing-entity
19772	// (the DC) and ensure that all intervening capturing-entities
19773	// (blocks/lambdas etc.) between the innermost capturer and the variable`s
19774	// declcontext can either capture the variable or have already captured
19775	// the variable.
19776	CaptureType = Var->getType();
19777	DeclRefType = CaptureType.getNonReferenceType();
19778	bool Nested = false;
19779	bool Explicit = (Kind != TryCapture_Implicit);
19780	unsigned FunctionScopesIndex = MaxFunctionScopesIndex;
19781	do {
19782
19783	LambdaScopeInfo *LSI = nullptr;
19784	if (!FunctionScopes.empty())
19785	LSI = dyn_cast_or_null<LambdaScopeInfo>(
19786	Val: FunctionScopes[FunctionScopesIndex]);
19787
19788	bool IsInScopeDeclarationContext =
19789	!LSI || LSI->AfterParameterList || CurContext == LSI->CallOperator;
19790
19791	if (LSI && !LSI->AfterParameterList) {
19792	// This allows capturing parameters from a default value which does not
19793	// seems correct
19794	if (isa<ParmVarDecl>(Val: Var) && !Var->getDeclContext()->isFunctionOrMethod())
19795	return true;
19796	}
19797	// If the variable is declared in the current context, there is no need to
19798	// capture it.
19799	if (IsInScopeDeclarationContext &&
19800	FunctionScopesIndex == MaxFunctionScopesIndex && VarDC == DC)
19801	return true;
19802
19803	// Only block literals, captured statements, and lambda expressions can
19804	// capture; other scopes don't work.
19805	DeclContext *ParentDC =
19806	!IsInScopeDeclarationContext
19807	? DC->getParent()
19808	: getParentOfCapturingContextOrNull(DC, Var, Loc: ExprLoc,
19809	Diagnose: BuildAndDiagnose, S&: *this);
19810	// We need to check for the parent *first* because, if we *have*
19811	// private-captured a global variable, we need to recursively capture it in
19812	// intermediate blocks, lambdas, etc.
19813	if (!ParentDC) {
19814	if (IsGlobal) {
19815	FunctionScopesIndex = MaxFunctionScopesIndex - 1;
19816	break;
19817	}
19818	return true;
19819	}
19820
19821	FunctionScopeInfo *FSI = FunctionScopes[FunctionScopesIndex];
19822	CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(Val: FSI);
19823
19824	// Check whether we've already captured it.
19825	if (isVariableAlreadyCapturedInScopeInfo(CSI, Var, SubCapturesAreNested&: Nested, CaptureType,
19826	DeclRefType)) {
19827	CSI->getCapture(Var).markUsed(IsODRUse: BuildAndDiagnose);
19828	break;
19829	}
19830
19831	// When evaluating some attributes (like enable_if) we might refer to a
19832	// function parameter appertaining to the same declaration as that
19833	// attribute.
19834	if (const auto *Parm = dyn_cast<ParmVarDecl>(Val: Var);
19835	Parm && Parm->getDeclContext() == DC)
19836	return true;
19837
19838	// If we are instantiating a generic lambda call operator body,
19839	// we do not want to capture new variables. What was captured
19840	// during either a lambdas transformation or initial parsing
19841	// should be used.
19842	if (isGenericLambdaCallOperatorSpecialization(DC)) {
19843	if (BuildAndDiagnose) {
19844	LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(Val: CSI);
19845	if (LSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None) {
19846	Diag(ExprLoc, diag::err_lambda_impcap) << Var;
19847	Diag(Var->getLocation(), diag::note_previous_decl) << Var;
19848	Diag(LSI->Lambda->getBeginLoc(), diag::note_lambda_decl);
19849	buildLambdaCaptureFixit(Sema&: *this, LSI, Var);
19850	} else
19851	diagnoseUncapturableValueReferenceOrBinding(S&: *this, loc: ExprLoc, var: Var);
19852	}
19853	return true;
19854	}
19855
19856	// Try to capture variable-length arrays types.
19857	if (Var->getType()->isVariablyModifiedType()) {
19858	// We're going to walk down into the type and look for VLA
19859	// expressions.
19860	QualType QTy = Var->getType();
19861	if (ParmVarDecl *PVD = dyn_cast_or_null<ParmVarDecl>(Val: Var))
19862	QTy = PVD->getOriginalType();
19863	captureVariablyModifiedType(Context, T: QTy, CSI);
19864	}
19865
19866	if (getLangOpts().OpenMP) {
19867	if (auto *RSI = dyn_cast<CapturedRegionScopeInfo>(Val: CSI)) {
19868	// OpenMP private variables should not be captured in outer scope, so
19869	// just break here. Similarly, global variables that are captured in a
19870	// target region should not be captured outside the scope of the region.
19871	if (RSI->CapRegionKind == CR_OpenMP) {
19872	// FIXME: We should support capturing structured bindings in OpenMP.
19873	if (isa<BindingDecl>(Val: Var)) {
19874	if (BuildAndDiagnose) {
19875	Diag(ExprLoc, diag::err_capture_binding_openmp) << Var;
19876	Diag(Var->getLocation(), diag::note_entity_declared_at) << Var;
19877	}
19878	return true;
19879	}
19880	OpenMPClauseKind IsOpenMPPrivateDecl = isOpenMPPrivateDecl(
19881	Var, RSI->OpenMPLevel, RSI->OpenMPCaptureLevel);
19882	// If the variable is private (i.e. not captured) and has variably
19883	// modified type, we still need to capture the type for correct
19884	// codegen in all regions, associated with the construct. Currently,
19885	// it is captured in the innermost captured region only.
19886	if (IsOpenMPPrivateDecl != OMPC_unknown &&
19887	Var->getType()->isVariablyModifiedType()) {
19888	QualType QTy = Var->getType();
19889	if (ParmVarDecl *PVD = dyn_cast_or_null<ParmVarDecl>(Val: Var))
19890	QTy = PVD->getOriginalType();
19891	for (int I = 1, E = getNumberOfConstructScopes(Level: RSI->OpenMPLevel);
19892	I < E; ++I) {
19893	auto *OuterRSI = cast<CapturedRegionScopeInfo>(
19894	Val: FunctionScopes[FunctionScopesIndex - I]);
19895	assert(RSI->OpenMPLevel == OuterRSI->OpenMPLevel &&
19896	"Wrong number of captured regions associated with the "
19897	"OpenMP construct.");
19898	captureVariablyModifiedType(Context, QTy, OuterRSI);
19899	}
19900	}
19901	bool IsTargetCap =
19902	IsOpenMPPrivateDecl != OMPC_private &&
19903	isOpenMPTargetCapturedDecl(Var, RSI->OpenMPLevel,
19904	RSI->OpenMPCaptureLevel);
19905	// Do not capture global if it is not privatized in outer regions.
19906	bool IsGlobalCap =
19907	IsGlobal && isOpenMPGlobalCapturedDecl(D: Var, Level: RSI->OpenMPLevel,
19908	CaptureLevel: RSI->OpenMPCaptureLevel);
19909
19910	// When we detect target captures we are looking from inside the
19911	// target region, therefore we need to propagate the capture from the
19912	// enclosing region. Therefore, the capture is not initially nested.
19913	if (IsTargetCap)
19914	adjustOpenMPTargetScopeIndex(FunctionScopesIndex, Level: RSI->OpenMPLevel);
19915
19916	if (IsTargetCap || IsOpenMPPrivateDecl == OMPC_private ||
19917	(IsGlobal && !IsGlobalCap)) {
19918	Nested = !IsTargetCap;
19919	bool HasConst = DeclRefType.isConstQualified();
19920	DeclRefType = DeclRefType.getUnqualifiedType();
19921	// Don't lose diagnostics about assignments to const.
19922	if (HasConst)
19923	DeclRefType.addConst();
19924	CaptureType = Context.getLValueReferenceType(T: DeclRefType);
19925	break;
19926	}
19927	}
19928	}
19929	}
19930	if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None && !Explicit) {
19931	// No capture-default, and this is not an explicit capture
19932	// so cannot capture this variable.
19933	if (BuildAndDiagnose) {
19934	Diag(ExprLoc, diag::err_lambda_impcap) << Var;
19935	Diag(Var->getLocation(), diag::note_previous_decl) << Var;
19936	auto *LSI = cast<LambdaScopeInfo>(Val: CSI);
19937	if (LSI->Lambda) {
19938	Diag(LSI->Lambda->getBeginLoc(), diag::note_lambda_decl);
19939	buildLambdaCaptureFixit(Sema&: *this, LSI, Var);
19940	}
19941	// FIXME: If we error out because an outer lambda can not implicitly
19942	// capture a variable that an inner lambda explicitly captures, we
19943	// should have the inner lambda do the explicit capture - because
19944	// it makes for cleaner diagnostics later. This would purely be done
19945	// so that the diagnostic does not misleadingly claim that a variable
19946	// can not be captured by a lambda implicitly even though it is captured
19947	// explicitly. Suggestion:
19948	// - create const bool VariableCaptureWasInitiallyExplicit = Explicit
19949	// at the function head
19950	// - cache the StartingDeclContext - this must be a lambda
19951	// - captureInLambda in the innermost lambda the variable.
19952	}
19953	return true;
19954	}
19955	Explicit = false;
19956	FunctionScopesIndex--;
19957	if (IsInScopeDeclarationContext)
19958	DC = ParentDC;
19959	} while (!VarDC->Equals(DC));
19960
19961	// Walk back down the scope stack, (e.g. from outer lambda to inner lambda)
19962	// computing the type of the capture at each step, checking type-specific
19963	// requirements, and adding captures if requested.
19964	// If the variable had already been captured previously, we start capturing
19965	// at the lambda nested within that one.
19966	bool Invalid = false;
19967	for (unsigned I = ++FunctionScopesIndex, N = MaxFunctionScopesIndex + 1; I != N;
19968	++I) {
19969	CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(Val: FunctionScopes[I]);
19970
19971	// Certain capturing entities (lambdas, blocks etc.) are not allowed to capture
19972	// certain types of variables (unnamed, variably modified types etc.)
19973	// so check for eligibility.
19974	if (!Invalid)
19975	Invalid =
19976	!isVariableCapturable(CSI, Var, Loc: ExprLoc, Diagnose: BuildAndDiagnose, S&: *this);
19977
19978	// After encountering an error, if we're actually supposed to capture, keep
19979	// capturing in nested contexts to suppress any follow-on diagnostics.
19980	if (Invalid && !BuildAndDiagnose)
19981	return true;
19982
19983	if (BlockScopeInfo *BSI = dyn_cast<BlockScopeInfo>(Val: CSI)) {
19984	Invalid = !captureInBlock(BSI, Var, Loc: ExprLoc, BuildAndDiagnose, CaptureType,
19985	DeclRefType, Nested, S&: *this, Invalid);
19986	Nested = true;
19987	} else if (CapturedRegionScopeInfo *RSI = dyn_cast<CapturedRegionScopeInfo>(Val: CSI)) {
19988	Invalid = !captureInCapturedRegion(
19989	RSI, Var, Loc: ExprLoc, BuildAndDiagnose, CaptureType, DeclRefType, RefersToCapturedVariable: Nested,
19990	Kind, /*IsTopScope*/ I == N - 1, S&: *this, Invalid);
19991	Nested = true;
19992	} else {
19993	LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(Val: CSI);
19994	Invalid =
19995	!captureInLambda(LSI, Var, Loc: ExprLoc, BuildAndDiagnose, CaptureType,
19996	DeclRefType, RefersToCapturedVariable: Nested, Kind, EllipsisLoc,
19997	/*IsTopScope*/ I == N - 1, S&: *this, Invalid);
19998	Nested = true;
19999	}
20000
20001	if (Invalid && !BuildAndDiagnose)
20002	return true;
20003	}
20004	return Invalid;
20005	}
20006
20007	bool Sema::tryCaptureVariable(ValueDecl *Var, SourceLocation Loc,
20008	TryCaptureKind Kind, SourceLocation EllipsisLoc) {
20009	QualType CaptureType;
20010	QualType DeclRefType;
20011	return tryCaptureVariable(Var, ExprLoc: Loc, Kind, EllipsisLoc,
20012	/*BuildAndDiagnose=*/true, CaptureType,
20013	DeclRefType, FunctionScopeIndexToStopAt: nullptr);
20014	}
20015
20016	bool Sema::NeedToCaptureVariable(ValueDecl *Var, SourceLocation Loc) {
20017	QualType CaptureType;
20018	QualType DeclRefType;
20019	return !tryCaptureVariable(Var, ExprLoc: Loc, Kind: TryCapture_Implicit, EllipsisLoc: SourceLocation(),
20020	/*BuildAndDiagnose=*/false, CaptureType,
20021	DeclRefType, FunctionScopeIndexToStopAt: nullptr);
20022	}
20023
20024	QualType Sema::getCapturedDeclRefType(ValueDecl *Var, SourceLocation Loc) {
20025	QualType CaptureType;
20026	QualType DeclRefType;
20027
20028	// Determine whether we can capture this variable.
20029	if (tryCaptureVariable(Var, ExprLoc: Loc, Kind: TryCapture_Implicit, EllipsisLoc: SourceLocation(),
20030	/*BuildAndDiagnose=*/false, CaptureType,
20031	DeclRefType, FunctionScopeIndexToStopAt: nullptr))
20032	return QualType();
20033
20034	return DeclRefType;
20035	}
20036
20037	namespace {
20038	// Helper to copy the template arguments from a DeclRefExpr or MemberExpr.
20039	// The produced TemplateArgumentListInfo* points to data stored within this
20040	// object, so should only be used in contexts where the pointer will not be
20041	// used after the CopiedTemplateArgs object is destroyed.
20042	class CopiedTemplateArgs {
20043	bool HasArgs;
20044	TemplateArgumentListInfo TemplateArgStorage;
20045	public:
20046	template<typename RefExpr>
20047	CopiedTemplateArgs(RefExpr *E) : HasArgs(E->hasExplicitTemplateArgs()) {
20048	if (HasArgs)
20049	E->copyTemplateArgumentsInto(TemplateArgStorage);
20050	}
20051	operator TemplateArgumentListInfo*()
20052	#ifdef __has_cpp_attribute
20053	#if __has_cpp_attribute(clang::lifetimebound)
20054	[[clang::lifetimebound]]
20055	#endif
20056	#endif
20057	{
20058	return HasArgs ? &TemplateArgStorage : nullptr;
20059	}
20060	};
20061	}
20062
20063	/// Walk the set of potential results of an expression and mark them all as
20064	/// non-odr-uses if they satisfy the side-conditions of the NonOdrUseReason.
20065	///
20066	/// \return A new expression if we found any potential results, ExprEmpty() if
20067	/// not, and ExprError() if we diagnosed an error.
20068	static ExprResult rebuildPotentialResultsAsNonOdrUsed(Sema &S, Expr *E,
20069	NonOdrUseReason NOUR) {
20070	// Per C++11 [basic.def.odr], a variable is odr-used "unless it is
20071	// an object that satisfies the requirements for appearing in a
20072	// constant expression (5.19) and the lvalue-to-rvalue conversion (4.1)
20073	// is immediately applied." This function handles the lvalue-to-rvalue
20074	// conversion part.
20075	//
20076	// If we encounter a node that claims to be an odr-use but shouldn't be, we
20077	// transform it into the relevant kind of non-odr-use node and rebuild the
20078	// tree of nodes leading to it.
20079	//
20080	// This is a mini-TreeTransform that only transforms a restricted subset of
20081	// nodes (and only certain operands of them).
20082
20083	// Rebuild a subexpression.
20084	auto Rebuild = [&](Expr *Sub) {
20085	return rebuildPotentialResultsAsNonOdrUsed(S, E: Sub, NOUR);
20086	};
20087
20088	// Check whether a potential result satisfies the requirements of NOUR.
20089	auto IsPotentialResultOdrUsed = [&](NamedDecl *D) {
20090	// Any entity other than a VarDecl is always odr-used whenever it's named
20091	// in a potentially-evaluated expression.
20092	auto *VD = dyn_cast<VarDecl>(Val: D);
20093	if (!VD)
20094	return true;
20095
20096	// C++2a [basic.def.odr]p4:
20097	// A variable x whose name appears as a potentially-evalauted expression
20098	// e is odr-used by e unless
20099	// -- x is a reference that is usable in constant expressions, or
20100	// -- x is a variable of non-reference type that is usable in constant
20101	// expressions and has no mutable subobjects, and e is an element of
20102	// the set of potential results of an expression of
20103	// non-volatile-qualified non-class type to which the lvalue-to-rvalue
20104	// conversion is applied, or
20105	// -- x is a variable of non-reference type, and e is an element of the
20106	// set of potential results of a discarded-value expression to which
20107	// the lvalue-to-rvalue conversion is not applied
20108	//
20109	// We check the first bullet and the "potentially-evaluated" condition in
20110	// BuildDeclRefExpr. We check the type requirements in the second bullet
20111	// in CheckLValueToRValueConversionOperand below.
20112	switch (NOUR) {
20113	case NOUR_None:
20114	case NOUR_Unevaluated:
20115	llvm_unreachable("unexpected non-odr-use-reason");
20116
20117	case NOUR_Constant:
20118	// Constant references were handled when they were built.
20119	if (VD->getType()->isReferenceType())
20120	return true;
20121	if (auto *RD = VD->getType()->getAsCXXRecordDecl())
20122	if (RD->hasMutableFields())
20123	return true;
20124	if (!VD->isUsableInConstantExpressions(C: S.Context))
20125	return true;
20126	break;
20127
20128	case NOUR_Discarded:
20129	if (VD->getType()->isReferenceType())
20130	return true;
20131	break;
20132	}
20133	return false;
20134	};
20135
20136	// Mark that this expression does not constitute an odr-use.
20137	auto MarkNotOdrUsed = [&] {
20138	S.MaybeODRUseExprs.remove(X: E);
20139	if (LambdaScopeInfo *LSI = S.getCurLambda())
20140	LSI->markVariableExprAsNonODRUsed(CapturingVarExpr: E);
20141	};
20142
20143	// C++2a [basic.def.odr]p2:
20144	// The set of potential results of an expression e is defined as follows:
20145	switch (E->getStmtClass()) {
20146	// -- If e is an id-expression, ...
20147	case Expr::DeclRefExprClass: {
20148	auto *DRE = cast<DeclRefExpr>(Val: E);
20149	if (DRE->isNonOdrUse() || IsPotentialResultOdrUsed(DRE->getDecl()))
20150	break;
20151
20152	// Rebuild as a non-odr-use DeclRefExpr.
20153	MarkNotOdrUsed();
20154	return DeclRefExpr::Create(
20155	S.Context, DRE->getQualifierLoc(), DRE->getTemplateKeywordLoc(),
20156	DRE->getDecl(), DRE->refersToEnclosingVariableOrCapture(),
20157	DRE->getNameInfo(), DRE->getType(), DRE->getValueKind(),
20158	DRE->getFoundDecl(), CopiedTemplateArgs(DRE), NOUR);
20159	}
20160
20161	case Expr::FunctionParmPackExprClass: {
20162	auto *FPPE = cast<FunctionParmPackExpr>(Val: E);
20163	// If any of the declarations in the pack is odr-used, then the expression
20164	// as a whole constitutes an odr-use.
20165	for (VarDecl *D : *FPPE)
20166	if (IsPotentialResultOdrUsed(D))
20167	return ExprEmpty();
20168
20169	// FIXME: Rebuild as a non-odr-use FunctionParmPackExpr? In practice,
20170	// nothing cares about whether we marked this as an odr-use, but it might
20171	// be useful for non-compiler tools.
20172	MarkNotOdrUsed();
20173	break;
20174	}
20175
20176	// -- If e is a subscripting operation with an array operand...
20177	case Expr::ArraySubscriptExprClass: {
20178	auto *ASE = cast<ArraySubscriptExpr>(Val: E);
20179	Expr *OldBase = ASE->getBase()->IgnoreImplicit();
20180	if (!OldBase->getType()->isArrayType())
20181	break;
20182	ExprResult Base = Rebuild(OldBase);
20183	if (!Base.isUsable())
20184	return Base;
20185	Expr *LHS = ASE->getBase() == ASE->getLHS() ? Base.get() : ASE->getLHS();
20186	Expr *RHS = ASE->getBase() == ASE->getRHS() ? Base.get() : ASE->getRHS();
20187	SourceLocation LBracketLoc = ASE->getBeginLoc(); // FIXME: Not stored.
20188	return S.ActOnArraySubscriptExpr(S: nullptr, base: LHS, lbLoc: LBracketLoc, ArgExprs: RHS,
20189	rbLoc: ASE->getRBracketLoc());
20190	}
20191
20192	case Expr::MemberExprClass: {
20193	auto *ME = cast<MemberExpr>(Val: E);
20194	// -- If e is a class member access expression [...] naming a non-static
20195	// data member...
20196	if (isa<FieldDecl>(Val: ME->getMemberDecl())) {
20197	ExprResult Base = Rebuild(ME->getBase());
20198	if (!Base.isUsable())
20199	return Base;
20200	return MemberExpr::Create(
20201	C: S.Context, Base: Base.get(), IsArrow: ME->isArrow(), OperatorLoc: ME->getOperatorLoc(),
20202	QualifierLoc: ME->getQualifierLoc(), TemplateKWLoc: ME->getTemplateKeywordLoc(),
20203	MemberDecl: ME->getMemberDecl(), FoundDecl: ME->getFoundDecl(), MemberNameInfo: ME->getMemberNameInfo(),
20204	TemplateArgs: CopiedTemplateArgs(ME), T: ME->getType(), VK: ME->getValueKind(),
20205	OK: ME->getObjectKind(), NOUR: ME->isNonOdrUse());
20206	}
20207
20208	if (ME->getMemberDecl()->isCXXInstanceMember())
20209	break;
20210
20211	// -- If e is a class member access expression naming a static data member,
20212	// ...
20213	if (ME->isNonOdrUse() || IsPotentialResultOdrUsed(ME->getMemberDecl()))
20214	break;
20215
20216	// Rebuild as a non-odr-use MemberExpr.
20217	MarkNotOdrUsed();
20218	return MemberExpr::Create(
20219	C: S.Context, Base: ME->getBase(), IsArrow: ME->isArrow(), OperatorLoc: ME->getOperatorLoc(),
20220	QualifierLoc: ME->getQualifierLoc(), TemplateKWLoc: ME->getTemplateKeywordLoc(), MemberDecl: ME->getMemberDecl(),
20221	FoundDecl: ME->getFoundDecl(), MemberNameInfo: ME->getMemberNameInfo(), TemplateArgs: CopiedTemplateArgs(ME),
20222	T: ME->getType(), VK: ME->getValueKind(), OK: ME->getObjectKind(), NOUR);
20223	}
20224
20225	case Expr::BinaryOperatorClass: {
20226	auto *BO = cast<BinaryOperator>(Val: E);
20227	Expr *LHS = BO->getLHS();
20228	Expr *RHS = BO->getRHS();
20229	// -- If e is a pointer-to-member expression of the form e1 .* e2 ...
20230	if (BO->getOpcode() == BO_PtrMemD) {
20231	ExprResult Sub = Rebuild(LHS);
20232	if (!Sub.isUsable())
20233	return Sub;
20234	LHS = Sub.get();
20235	// -- If e is a comma expression, ...
20236	} else if (BO->getOpcode() == BO_Comma) {
20237	ExprResult Sub = Rebuild(RHS);
20238	if (!Sub.isUsable())
20239	return Sub;
20240	RHS = Sub.get();
20241	} else {
20242	break;
20243	}
20244	return S.BuildBinOp(S: nullptr, OpLoc: BO->getOperatorLoc(), Opc: BO->getOpcode(),
20245	LHSExpr: LHS, RHSExpr: RHS);
20246	}
20247
20248	// -- If e has the form (e1)...
20249	case Expr::ParenExprClass: {
20250	auto *PE = cast<ParenExpr>(Val: E);
20251	ExprResult Sub = Rebuild(PE->getSubExpr());
20252	if (!Sub.isUsable())
20253	return Sub;
20254	return S.ActOnParenExpr(L: PE->getLParen(), R: PE->getRParen(), E: Sub.get());
20255	}
20256
20257	// -- If e is a glvalue conditional expression, ...
20258	// We don't apply this to a binary conditional operator. FIXME: Should we?
20259	case Expr::ConditionalOperatorClass: {
20260	auto *CO = cast<ConditionalOperator>(Val: E);
20261	ExprResult LHS = Rebuild(CO->getLHS());
20262	if (LHS.isInvalid())
20263	return ExprError();
20264	ExprResult RHS = Rebuild(CO->getRHS());
20265	if (RHS.isInvalid())
20266	return ExprError();
20267	if (!LHS.isUsable() && !RHS.isUsable())
20268	return ExprEmpty();
20269	if (!LHS.isUsable())
20270	LHS = CO->getLHS();
20271	if (!RHS.isUsable())
20272	RHS = CO->getRHS();
20273	return S.ActOnConditionalOp(QuestionLoc: CO->getQuestionLoc(), ColonLoc: CO->getColonLoc(),
20274	CondExpr: CO->getCond(), LHSExpr: LHS.get(), RHSExpr: RHS.get());
20275	}
20276
20277	// [Clang extension]
20278	// -- If e has the form __extension__ e1...
20279	case Expr::UnaryOperatorClass: {
20280	auto *UO = cast<UnaryOperator>(Val: E);
20281	if (UO->getOpcode() != UO_Extension)
20282	break;
20283	ExprResult Sub = Rebuild(UO->getSubExpr());
20284	if (!Sub.isUsable())
20285	return Sub;
20286	return S.BuildUnaryOp(S: nullptr, OpLoc: UO->getOperatorLoc(), Opc: UO_Extension,
20287	Input: Sub.get());
20288	}
20289
20290	// [Clang extension]
20291	// -- If e has the form _Generic(...), the set of potential results is the
20292	// union of the sets of potential results of the associated expressions.
20293	case Expr::GenericSelectionExprClass: {
20294	auto *GSE = cast<GenericSelectionExpr>(Val: E);
20295
20296	SmallVector<Expr *, 4> AssocExprs;
20297	bool AnyChanged = false;
20298	for (Expr *OrigAssocExpr : GSE->getAssocExprs()) {
20299	ExprResult AssocExpr = Rebuild(OrigAssocExpr);
20300	if (AssocExpr.isInvalid())
20301	return ExprError();
20302	if (AssocExpr.isUsable()) {
20303	AssocExprs.push_back(Elt: AssocExpr.get());
20304	AnyChanged = true;
20305	} else {
20306	AssocExprs.push_back(Elt: OrigAssocExpr);
20307	}
20308	}
20309
20310	void *ExOrTy = nullptr;
20311	bool IsExpr = GSE->isExprPredicate();
20312	if (IsExpr)
20313	ExOrTy = GSE->getControllingExpr();
20314	else
20315	ExOrTy = GSE->getControllingType();
20316	return AnyChanged ? S.CreateGenericSelectionExpr(
20317	KeyLoc: GSE->getGenericLoc(), DefaultLoc: GSE->getDefaultLoc(),
20318	RParenLoc: GSE->getRParenLoc(), PredicateIsExpr: IsExpr, ControllingExprOrType: ExOrTy,
20319	Types: GSE->getAssocTypeSourceInfos(), Exprs: AssocExprs)
20320	: ExprEmpty();
20321	}
20322
20323	// [Clang extension]
20324	// -- If e has the form __builtin_choose_expr(...), the set of potential
20325	// results is the union of the sets of potential results of the
20326	// second and third subexpressions.
20327	case Expr::ChooseExprClass: {
20328	auto *CE = cast<ChooseExpr>(Val: E);
20329
20330	ExprResult LHS = Rebuild(CE->getLHS());
20331	if (LHS.isInvalid())
20332	return ExprError();
20333
20334	ExprResult RHS = Rebuild(CE->getLHS());
20335	if (RHS.isInvalid())
20336	return ExprError();
20337
20338	if (!LHS.get() && !RHS.get())
20339	return ExprEmpty();
20340	if (!LHS.isUsable())
20341	LHS = CE->getLHS();
20342	if (!RHS.isUsable())
20343	RHS = CE->getRHS();
20344
20345	return S.ActOnChooseExpr(BuiltinLoc: CE->getBuiltinLoc(), CondExpr: CE->getCond(), LHSExpr: LHS.get(),
20346	RHSExpr: RHS.get(), RPLoc: CE->getRParenLoc());
20347	}
20348
20349	// Step through non-syntactic nodes.
20350	case Expr::ConstantExprClass: {
20351	auto *CE = cast<ConstantExpr>(Val: E);
20352	ExprResult Sub = Rebuild(CE->getSubExpr());
20353	if (!Sub.isUsable())
20354	return Sub;
20355	return ConstantExpr::Create(Context: S.Context, E: Sub.get());
20356	}
20357
20358	// We could mostly rely on the recursive rebuilding to rebuild implicit
20359	// casts, but not at the top level, so rebuild them here.
20360	case Expr::ImplicitCastExprClass: {
20361	auto *ICE = cast<ImplicitCastExpr>(Val: E);
20362	// Only step through the narrow set of cast kinds we expect to encounter.
20363	// Anything else suggests we've left the region in which potential results
20364	// can be found.
20365	switch (ICE->getCastKind()) {
20366	case CK_NoOp:
20367	case CK_DerivedToBase:
20368	case CK_UncheckedDerivedToBase: {
20369	ExprResult Sub = Rebuild(ICE->getSubExpr());
20370	if (!Sub.isUsable())
20371	return Sub;
20372	CXXCastPath Path(ICE->path());
20373	return S.ImpCastExprToType(E: Sub.get(), Type: ICE->getType(), CK: ICE->getCastKind(),
20374	VK: ICE->getValueKind(), BasePath: &Path);
20375	}
20376
20377	default:
20378	break;
20379	}
20380	break;
20381	}
20382
20383	default:
20384	break;
20385	}
20386
20387	// Can't traverse through this node. Nothing to do.
20388	return ExprEmpty();
20389	}
20390
20391	ExprResult Sema::CheckLValueToRValueConversionOperand(Expr *E) {
20392	// Check whether the operand is or contains an object of non-trivial C union
20393	// type.
20394	if (E->getType().isVolatileQualified() &&
20395	(E->getType().hasNonTrivialToPrimitiveDestructCUnion() ||
20396	E->getType().hasNonTrivialToPrimitiveCopyCUnion()))
20397	checkNonTrivialCUnion(QT: E->getType(), Loc: E->getExprLoc(),
20398	UseContext: Sema::NTCUC_LValueToRValueVolatile,
20399	NonTrivialKind: NTCUK_Destruct|NTCUK_Copy);
20400
20401	// C++2a [basic.def.odr]p4:
20402	// [...] an expression of non-volatile-qualified non-class type to which
20403	// the lvalue-to-rvalue conversion is applied [...]
20404	if (E->getType().isVolatileQualified() || E->getType()->getAs<RecordType>())
20405	return E;
20406
20407	ExprResult Result =
20408	rebuildPotentialResultsAsNonOdrUsed(S&: *this, E, NOUR: NOUR_Constant);
20409	if (Result.isInvalid())
20410	return ExprError();
20411	return Result.get() ? Result : E;
20412	}
20413
20414	ExprResult Sema::ActOnConstantExpression(ExprResult Res) {
20415	Res = CorrectDelayedTyposInExpr(ER: Res);
20416
20417	if (!Res.isUsable())
20418	return Res;
20419
20420	// If a constant-expression is a reference to a variable where we delay
20421	// deciding whether it is an odr-use, just assume we will apply the
20422	// lvalue-to-rvalue conversion. In the one case where this doesn't happen
20423	// (a non-type template argument), we have special handling anyway.
20424	return CheckLValueToRValueConversionOperand(E: Res.get());
20425	}
20426
20427	void Sema::CleanupVarDeclMarking() {
20428	// Iterate through a local copy in case MarkVarDeclODRUsed makes a recursive
20429	// call.
20430	MaybeODRUseExprSet LocalMaybeODRUseExprs;
20431	std::swap(LHS&: LocalMaybeODRUseExprs, RHS&: MaybeODRUseExprs);
20432
20433	for (Expr *E : LocalMaybeODRUseExprs) {
20434	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: E)) {
20435	MarkVarDeclODRUsed(cast<VarDecl>(Val: DRE->getDecl()),
20436	DRE->getLocation(), *this);
20437	} else if (auto *ME = dyn_cast<MemberExpr>(Val: E)) {
20438	MarkVarDeclODRUsed(cast<VarDecl>(Val: ME->getMemberDecl()), ME->getMemberLoc(),
20439	*this);
20440	} else if (auto *FP = dyn_cast<FunctionParmPackExpr>(Val: E)) {
20441	for (VarDecl *VD : *FP)
20442	MarkVarDeclODRUsed(VD, FP->getParameterPackLocation(), *this);
20443	} else {
20444	llvm_unreachable("Unexpected expression");
20445	}
20446	}
20447
20448	assert(MaybeODRUseExprs.empty() &&
20449	"MarkVarDeclODRUsed failed to cleanup MaybeODRUseExprs?");
20450	}
20451
20452	static void DoMarkPotentialCapture(Sema &SemaRef, SourceLocation Loc,
20453	ValueDecl *Var, Expr *E) {
20454	VarDecl *VD = Var->getPotentiallyDecomposedVarDecl();
20455	if (!VD)
20456	return;
20457
20458	const bool RefersToEnclosingScope =
20459	(SemaRef.CurContext != VD->getDeclContext() &&
20460	VD->getDeclContext()->isFunctionOrMethod() && VD->hasLocalStorage());
20461	if (RefersToEnclosingScope) {
20462	LambdaScopeInfo *const LSI =
20463	SemaRef.getCurLambda(/*IgnoreNonLambdaCapturingScope=*/true);
20464	if (LSI && (!LSI->CallOperator ||
20465	!LSI->CallOperator->Encloses(DC: Var->getDeclContext()))) {
20466	// If a variable could potentially be odr-used, defer marking it so
20467	// until we finish analyzing the full expression for any
20468	// lvalue-to-rvalue
20469	// or discarded value conversions that would obviate odr-use.
20470	// Add it to the list of potential captures that will be analyzed
20471	// later (ActOnFinishFullExpr) for eventual capture and odr-use marking
20472	// unless the variable is a reference that was initialized by a constant
20473	// expression (this will never need to be captured or odr-used).
20474	//
20475	// FIXME: We can simplify this a lot after implementing P0588R1.
20476	assert(E && "Capture variable should be used in an expression.");
20477	if (!Var->getType()->isReferenceType() ||
20478	!VD->isUsableInConstantExpressions(C: SemaRef.Context))
20479	LSI->addPotentialCapture(VarExpr: E->IgnoreParens());
20480	}
20481	}
20482	}
20483
20484	static void DoMarkVarDeclReferenced(
20485	Sema &SemaRef, SourceLocation Loc, VarDecl *Var, Expr *E,
20486	llvm::DenseMap<const VarDecl *, int> &RefsMinusAssignments) {
20487	assert((!E || isa<DeclRefExpr>(E) || isa<MemberExpr>(E) ||
20488	isa<FunctionParmPackExpr>(E)) &&
20489	"Invalid Expr argument to DoMarkVarDeclReferenced");
20490	Var->setReferenced();
20491
20492	if (Var->isInvalidDecl())
20493	return;
20494
20495	auto *MSI = Var->getMemberSpecializationInfo();
20496	TemplateSpecializationKind TSK = MSI ? MSI->getTemplateSpecializationKind()
20497	: Var->getTemplateSpecializationKind();
20498
20499	OdrUseContext OdrUse = isOdrUseContext(SemaRef);
20500	bool UsableInConstantExpr =
20501	Var->mightBeUsableInConstantExpressions(C: SemaRef.Context);
20502
20503	if (Var->isLocalVarDeclOrParm() && !Var->hasExternalStorage()) {
20504	RefsMinusAssignments.insert(KV: {Var, 0}).first->getSecond()++;
20505	}
20506
20507	// C++20 [expr.const]p12:
20508	// A variable [...] is needed for constant evaluation if it is [...] a
20509	// variable whose name appears as a potentially constant evaluated
20510	// expression that is either a contexpr variable or is of non-volatile
20511	// const-qualified integral type or of reference type
20512	bool NeededForConstantEvaluation =
20513	isPotentiallyConstantEvaluatedContext(SemaRef) && UsableInConstantExpr;
20514
20515	bool NeedDefinition =
20516	OdrUse == OdrUseContext::Used || NeededForConstantEvaluation;
20517
20518	assert(!isa<VarTemplatePartialSpecializationDecl>(Var) &&
20519	"Can't instantiate a partial template specialization.");
20520
20521	// If this might be a member specialization of a static data member, check
20522	// the specialization is visible. We already did the checks for variable
20523	// template specializations when we created them.
20524	if (NeedDefinition && TSK != TSK_Undeclared &&
20525	!isa<VarTemplateSpecializationDecl>(Val: Var))
20526	SemaRef.checkSpecializationVisibility(Loc, Var);
20527
20528	// Perform implicit instantiation of static data members, static data member
20529	// templates of class templates, and variable template specializations. Delay
20530	// instantiations of variable templates, except for those that could be used
20531	// in a constant expression.
20532	if (NeedDefinition && isTemplateInstantiation(Kind: TSK)) {
20533	// Per C++17 [temp.explicit]p10, we may instantiate despite an explicit
20534	// instantiation declaration if a variable is usable in a constant
20535	// expression (among other cases).
20536	bool TryInstantiating =
20537	TSK == TSK_ImplicitInstantiation ||
20538	(TSK == TSK_ExplicitInstantiationDeclaration && UsableInConstantExpr);
20539
20540	if (TryInstantiating) {
20541	SourceLocation PointOfInstantiation =
20542	MSI ? MSI->getPointOfInstantiation() : Var->getPointOfInstantiation();
20543	bool FirstInstantiation = PointOfInstantiation.isInvalid();
20544	if (FirstInstantiation) {
20545	PointOfInstantiation = Loc;
20546	if (MSI)
20547	MSI->setPointOfInstantiation(PointOfInstantiation);
20548	// FIXME: Notify listener.
20549	else
20550	Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
20551	}
20552
20553	if (UsableInConstantExpr) {
20554	// Do not defer instantiations of variables that could be used in a
20555	// constant expression.
20556	SemaRef.runWithSufficientStackSpace(Loc: PointOfInstantiation, Fn: [&] {
20557	SemaRef.InstantiateVariableDefinition(PointOfInstantiation, Var);
20558	});
20559
20560	// Re-set the member to trigger a recomputation of the dependence bits
20561	// for the expression.
20562	if (auto *DRE = dyn_cast_or_null<DeclRefExpr>(Val: E))
20563	DRE->setDecl(DRE->getDecl());
20564	else if (auto *ME = dyn_cast_or_null<MemberExpr>(Val: E))
20565	ME->setMemberDecl(ME->getMemberDecl());
20566	} else if (FirstInstantiation) {
20567	SemaRef.PendingInstantiations
20568	.push_back(std::make_pair(x&: Var, y&: PointOfInstantiation));
20569	} else {
20570	bool Inserted = false;
20571	for (auto &I : SemaRef.SavedPendingInstantiations) {
20572	auto Iter = llvm::find_if(
20573	Range&: I, P: [Var](const Sema::PendingImplicitInstantiation &P) {
20574	return P.first == Var;
20575	});
20576	if (Iter != I.end()) {
20577	SemaRef.PendingInstantiations.push_back(x: *Iter);
20578	I.erase(position: Iter);
20579	Inserted = true;
20580	break;
20581	}
20582	}
20583
20584	// FIXME: For a specialization of a variable template, we don't
20585	// distinguish between "declaration and type implicitly instantiated"
20586	// and "implicit instantiation of definition requested", so we have
20587	// no direct way to avoid enqueueing the pending instantiation
20588	// multiple times.
20589	if (isa<VarTemplateSpecializationDecl>(Val: Var) && !Inserted)
20590	SemaRef.PendingInstantiations
20591	.push_back(std::make_pair(x&: Var, y&: PointOfInstantiation));
20592	}
20593	}
20594	}
20595
20596	// C++2a [basic.def.odr]p4:
20597	// A variable x whose name appears as a potentially-evaluated expression e
20598	// is odr-used by e unless
20599	// -- x is a reference that is usable in constant expressions
20600	// -- x is a variable of non-reference type that is usable in constant
20601	// expressions and has no mutable subobjects [FIXME], and e is an
20602	// element of the set of potential results of an expression of
20603	// non-volatile-qualified non-class type to which the lvalue-to-rvalue
20604	// conversion is applied
20605	// -- x is a variable of non-reference type, and e is an element of the set
20606	// of potential results of a discarded-value expression to which the
20607	// lvalue-to-rvalue conversion is not applied [FIXME]
20608	//
20609	// We check the first part of the second bullet here, and
20610	// Sema::CheckLValueToRValueConversionOperand deals with the second part.
20611	// FIXME: To get the third bullet right, we need to delay this even for
20612	// variables that are not usable in constant expressions.
20613
20614	// If we already know this isn't an odr-use, there's nothing more to do.
20615	if (DeclRefExpr *DRE = dyn_cast_or_null<DeclRefExpr>(Val: E))
20616	if (DRE->isNonOdrUse())
20617	return;
20618	if (MemberExpr *ME = dyn_cast_or_null<MemberExpr>(Val: E))
20619	if (ME->isNonOdrUse())
20620	return;
20621
20622	switch (OdrUse) {
20623	case OdrUseContext::None:
20624	// In some cases, a variable may not have been marked unevaluated, if it
20625	// appears in a defaukt initializer.
20626	assert((!E || isa<FunctionParmPackExpr>(E) ||
20627	SemaRef.isUnevaluatedContext()) &&
20628	"missing non-odr-use marking for unevaluated decl ref");
20629	break;
20630
20631	case OdrUseContext::FormallyOdrUsed:
20632	// FIXME: Ignoring formal odr-uses results in incorrect lambda capture
20633	// behavior.
20634	break;
20635
20636	case OdrUseContext::Used:
20637	// If we might later find that this expression isn't actually an odr-use,
20638	// delay the marking.
20639	if (E && Var->isUsableInConstantExpressions(C: SemaRef.Context))
20640	SemaRef.MaybeODRUseExprs.insert(X: E);
20641	else
20642	MarkVarDeclODRUsed(Var, Loc, SemaRef);
20643	break;
20644
20645	case OdrUseContext::Dependent:
20646	// If this is a dependent context, we don't need to mark variables as
20647	// odr-used, but we may still need to track them for lambda capture.
20648	// FIXME: Do we also need to do this inside dependent typeid expressions
20649	// (which are modeled as unevaluated at this point)?
20650	DoMarkPotentialCapture(SemaRef, Loc, Var, E);
20651	break;
20652	}
20653	}
20654
20655	static void DoMarkBindingDeclReferenced(Sema &SemaRef, SourceLocation Loc,
20656	BindingDecl *BD, Expr *E) {
20657	BD->setReferenced();
20658
20659	if (BD->isInvalidDecl())
20660	return;
20661
20662	OdrUseContext OdrUse = isOdrUseContext(SemaRef);
20663	if (OdrUse == OdrUseContext::Used) {
20664	QualType CaptureType, DeclRefType;
20665	SemaRef.tryCaptureVariable(BD, Loc, Sema::TryCapture_Implicit,
20666	/*EllipsisLoc*/ SourceLocation(),
20667	/*BuildAndDiagnose*/ true, CaptureType,
20668	DeclRefType,
20669	/*FunctionScopeIndexToStopAt*/ nullptr);
20670	} else if (OdrUse == OdrUseContext::Dependent) {
20671	DoMarkPotentialCapture(SemaRef, Loc, BD, E);
20672	}
20673	}
20674
20675	/// Mark a variable referenced, and check whether it is odr-used
20676	/// (C++ [basic.def.odr]p2, C99 6.9p3). Note that this should not be
20677	/// used directly for normal expressions referring to VarDecl.
20678	void Sema::MarkVariableReferenced(SourceLocation Loc, VarDecl *Var) {
20679	DoMarkVarDeclReferenced(SemaRef&: *this, Loc, Var, E: nullptr, RefsMinusAssignments);
20680	}
20681
20682	// C++ [temp.dep.expr]p3:
20683	// An id-expression is type-dependent if it contains:
20684	// - an identifier associated by name lookup with an entity captured by copy
20685	// in a lambda-expression that has an explicit object parameter whose type
20686	// is dependent ([dcl.fct]),
20687	static void FixDependencyOfIdExpressionsInLambdaWithDependentObjectParameter(
20688	Sema &SemaRef, ValueDecl *D, Expr *E) {
20689	auto *ID = dyn_cast<DeclRefExpr>(Val: E);
20690	if (!ID || ID->isTypeDependent())
20691	return;
20692
20693	auto IsDependent = [&]() {
20694	const LambdaScopeInfo *LSI = SemaRef.getCurLambda();
20695	if (!LSI)
20696	return false;
20697	if (!LSI->ExplicitObjectParameter ||
20698	!LSI->ExplicitObjectParameter->getType()->isDependentType())
20699	return false;
20700	if (!LSI->CaptureMap.count(Val: D))
20701	return false;
20702	const Capture &Cap = LSI->getCapture(D);
20703	return !Cap.isCopyCapture();
20704	}();
20705
20706	ID->setCapturedByCopyInLambdaWithExplicitObjectParameter(
20707	Set: IsDependent, Context: SemaRef.getASTContext());
20708	}
20709
20710	static void
20711	MarkExprReferenced(Sema &SemaRef, SourceLocation Loc, Decl *D, Expr *E,
20712	bool MightBeOdrUse,
20713	llvm::DenseMap<const VarDecl *, int> &RefsMinusAssignments) {
20714	if (SemaRef.isInOpenMPDeclareTargetContext())
20715	SemaRef.checkDeclIsAllowedInOpenMPTarget(E, D);
20716
20717	if (VarDecl *Var = dyn_cast<VarDecl>(Val: D)) {
20718	DoMarkVarDeclReferenced(SemaRef, Loc, Var, E, RefsMinusAssignments);
20719	if (SemaRef.getLangOpts().CPlusPlus)
20720	FixDependencyOfIdExpressionsInLambdaWithDependentObjectParameter(SemaRef,
20721	Var, E);
20722	return;
20723	}
20724
20725	if (BindingDecl *Decl = dyn_cast<BindingDecl>(Val: D)) {
20726	DoMarkBindingDeclReferenced(SemaRef, Loc, BD: Decl, E);
20727	if (SemaRef.getLangOpts().CPlusPlus)
20728	FixDependencyOfIdExpressionsInLambdaWithDependentObjectParameter(SemaRef,
20729	Decl, E);
20730	return;
20731	}
20732	SemaRef.MarkAnyDeclReferenced(Loc, D, MightBeOdrUse);
20733
20734	// If this is a call to a method via a cast, also mark the method in the
20735	// derived class used in case codegen can devirtualize the call.
20736	const MemberExpr *ME = dyn_cast<MemberExpr>(Val: E);
20737	if (!ME)
20738	return;
20739	CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Val: ME->getMemberDecl());
20740	if (!MD)
20741	return;
20742	// Only attempt to devirtualize if this is truly a virtual call.
20743	bool IsVirtualCall = MD->isVirtual() &&
20744	ME->performsVirtualDispatch(LO: SemaRef.getLangOpts());
20745	if (!IsVirtualCall)
20746	return;
20747
20748	// If it's possible to devirtualize the call, mark the called function
20749	// referenced.
20750	CXXMethodDecl *DM = MD->getDevirtualizedMethod(
20751	Base: ME->getBase(), IsAppleKext: SemaRef.getLangOpts().AppleKext);
20752	if (DM)
20753	SemaRef.MarkAnyDeclReferenced(Loc, DM, MightBeOdrUse);
20754	}
20755
20756	/// Perform reference-marking and odr-use handling for a DeclRefExpr.
20757	///
20758	/// Note, this may change the dependence of the DeclRefExpr, and so needs to be
20759	/// handled with care if the DeclRefExpr is not newly-created.
20760	void Sema::MarkDeclRefReferenced(DeclRefExpr *E, const Expr *Base) {
20761	// TODO: update this with DR# once a defect report is filed.
20762	// C++11 defect. The address of a pure member should not be an ODR use, even
20763	// if it's a qualified reference.
20764	bool OdrUse = true;
20765	if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Val: E->getDecl()))
20766	if (Method->isVirtual() &&
20767	!Method->getDevirtualizedMethod(Base, IsAppleKext: getLangOpts().AppleKext))
20768	OdrUse = false;
20769
20770	if (auto *FD = dyn_cast<FunctionDecl>(Val: E->getDecl())) {
20771	if (!isUnevaluatedContext() && !isConstantEvaluatedContext() &&
20772	!isImmediateFunctionContext() &&
20773	!isCheckingDefaultArgumentOrInitializer() &&
20774	FD->isImmediateFunction() && !RebuildingImmediateInvocation &&
20775	!FD->isDependentContext())
20776	ExprEvalContexts.back().ReferenceToConsteval.insert(Ptr: E);
20777	}
20778	MarkExprReferenced(*this, E->getLocation(), E->getDecl(), E, OdrUse,
20779	RefsMinusAssignments);
20780	}
20781
20782	/// Perform reference-marking and odr-use handling for a MemberExpr.
20783	void Sema::MarkMemberReferenced(MemberExpr *E) {
20784	// C++11 [basic.def.odr]p2:
20785	// A non-overloaded function whose name appears as a potentially-evaluated
20786	// expression or a member of a set of candidate functions, if selected by
20787	// overload resolution when referred to from a potentially-evaluated
20788	// expression, is odr-used, unless it is a pure virtual function and its
20789	// name is not explicitly qualified.
20790	bool MightBeOdrUse = true;
20791	if (E->performsVirtualDispatch(LO: getLangOpts())) {
20792	if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Val: E->getMemberDecl()))
20793	if (Method->isPureVirtual())
20794	MightBeOdrUse = false;
20795	}
20796	SourceLocation Loc =
20797	E->getMemberLoc().isValid() ? E->getMemberLoc() : E->getBeginLoc();
20798	MarkExprReferenced(*this, Loc, E->getMemberDecl(), E, MightBeOdrUse,
20799	RefsMinusAssignments);
20800	}
20801
20802	/// Perform reference-marking and odr-use handling for a FunctionParmPackExpr.
20803	void Sema::MarkFunctionParmPackReferenced(FunctionParmPackExpr *E) {
20804	for (VarDecl *VD : *E)
20805	MarkExprReferenced(*this, E->getParameterPackLocation(), VD, E, true,
20806	RefsMinusAssignments);
20807	}
20808
20809	/// Perform marking for a reference to an arbitrary declaration. It
20810	/// marks the declaration referenced, and performs odr-use checking for
20811	/// functions and variables. This method should not be used when building a
20812	/// normal expression which refers to a variable.
20813	void Sema::MarkAnyDeclReferenced(SourceLocation Loc, Decl *D,
20814	bool MightBeOdrUse) {
20815	if (MightBeOdrUse) {
20816	if (auto *VD = dyn_cast<VarDecl>(Val: D)) {
20817	MarkVariableReferenced(Loc, Var: VD);
20818	return;
20819	}
20820	}
20821	if (auto *FD = dyn_cast<FunctionDecl>(Val: D)) {
20822	MarkFunctionReferenced(Loc, Func: FD, MightBeOdrUse);
20823	return;
20824	}
20825	D->setReferenced();
20826	}
20827
20828	namespace {
20829	// Mark all of the declarations used by a type as referenced.
20830	// FIXME: Not fully implemented yet! We need to have a better understanding
20831	// of when we're entering a context we should not recurse into.
20832	// FIXME: This is and EvaluatedExprMarker are more-or-less equivalent to
20833	// TreeTransforms rebuilding the type in a new context. Rather than
20834	// duplicating the TreeTransform logic, we should consider reusing it here.
20835	// Currently that causes problems when rebuilding LambdaExprs.
20836	class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> {
20837	Sema &S;
20838	SourceLocation Loc;
20839
20840	public:
20841	typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited;
20842
20843	MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { }
20844
20845	bool TraverseTemplateArgument(const TemplateArgument &Arg);
20846	};
20847	}
20848
20849	bool MarkReferencedDecls::TraverseTemplateArgument(
20850	const TemplateArgument &Arg) {
20851	{
20852	// A non-type template argument is a constant-evaluated context.
20853	EnterExpressionEvaluationContext Evaluated(
20854	S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
20855	if (Arg.getKind() == TemplateArgument::Declaration) {
20856	if (Decl *D = Arg.getAsDecl())
20857	S.MarkAnyDeclReferenced(Loc, D, MightBeOdrUse: true);
20858	} else if (Arg.getKind() == TemplateArgument::Expression) {
20859	S.MarkDeclarationsReferencedInExpr(E: Arg.getAsExpr(), SkipLocalVariables: false);
20860	}
20861	}
20862
20863	return Inherited::TraverseTemplateArgument(Arg);
20864	}
20865
20866	void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) {
20867	MarkReferencedDecls Marker(*this, Loc);
20868	Marker.TraverseType(T);
20869	}
20870
20871	namespace {
20872	/// Helper class that marks all of the declarations referenced by
20873	/// potentially-evaluated subexpressions as "referenced".
20874	class EvaluatedExprMarker : public UsedDeclVisitor<EvaluatedExprMarker> {
20875	public:
20876	typedef UsedDeclVisitor<EvaluatedExprMarker> Inherited;
20877	bool SkipLocalVariables;
20878	ArrayRef<const Expr *> StopAt;
20879
20880	EvaluatedExprMarker(Sema &S, bool SkipLocalVariables,
20881	ArrayRef<const Expr *> StopAt)
20882	: Inherited(S), SkipLocalVariables(SkipLocalVariables), StopAt(StopAt) {}
20883
20884	void visitUsedDecl(SourceLocation Loc, Decl *D) {
20885	S.MarkFunctionReferenced(Loc, Func: cast<FunctionDecl>(Val: D));
20886	}
20887
20888	void Visit(Expr *E) {
20889	if (llvm::is_contained(Range&: StopAt, Element: E))
20890	return;
20891	Inherited::Visit(E);
20892	}
20893
20894	void VisitConstantExpr(ConstantExpr *E) {
20895	// Don't mark declarations within a ConstantExpression, as this expression
20896	// will be evaluated and folded to a value.
20897	}
20898
20899	void VisitDeclRefExpr(DeclRefExpr *E) {
20900	// If we were asked not to visit local variables, don't.
20901	if (SkipLocalVariables) {
20902	if (VarDecl *VD = dyn_cast<VarDecl>(Val: E->getDecl()))
20903	if (VD->hasLocalStorage())
20904	return;
20905	}
20906
20907	// FIXME: This can trigger the instantiation of the initializer of a
20908	// variable, which can cause the expression to become value-dependent
20909	// or error-dependent. Do we need to propagate the new dependence bits?
20910	S.MarkDeclRefReferenced(E);
20911	}
20912
20913	void VisitMemberExpr(MemberExpr *E) {
20914	S.MarkMemberReferenced(E);
20915	Visit(E: E->getBase());
20916	}
20917	};
20918	} // namespace
20919
20920	/// Mark any declarations that appear within this expression or any
20921	/// potentially-evaluated subexpressions as "referenced".
20922	///
20923	/// \param SkipLocalVariables If true, don't mark local variables as
20924	/// 'referenced'.
20925	/// \param StopAt Subexpressions that we shouldn't recurse into.
20926	void Sema::MarkDeclarationsReferencedInExpr(Expr *E,
20927	bool SkipLocalVariables,
20928	ArrayRef<const Expr*> StopAt) {
20929	EvaluatedExprMarker(*this, SkipLocalVariables, StopAt).Visit(E);
20930	}
20931
20932	/// Emit a diagnostic when statements are reachable.
20933	/// FIXME: check for reachability even in expressions for which we don't build a
20934	/// CFG (eg, in the initializer of a global or in a constant expression).
20935	/// For example,
20936	/// namespace { auto *p = new double[3][false ? (1, 2) : 3]; }
20937	bool Sema::DiagIfReachable(SourceLocation Loc, ArrayRef<const Stmt *> Stmts,
20938	const PartialDiagnostic &PD) {
20939	if (!Stmts.empty() && getCurFunctionOrMethodDecl()) {
20940	if (!FunctionScopes.empty())
20941	FunctionScopes.back()->PossiblyUnreachableDiags.push_back(
20942	Elt: sema::PossiblyUnreachableDiag(PD, Loc, Stmts));
20943	return true;
20944	}
20945
20946	// The initializer of a constexpr variable or of the first declaration of a
20947	// static data member is not syntactically a constant evaluated constant,
20948	// but nonetheless is always required to be a constant expression, so we
20949	// can skip diagnosing.
20950	// FIXME: Using the mangling context here is a hack.
20951	if (auto *VD = dyn_cast_or_null<VarDecl>(
20952	Val: ExprEvalContexts.back().ManglingContextDecl)) {
20953	if (VD->isConstexpr() ||
20954	(VD->isStaticDataMember() && VD->isFirstDecl() && !VD->isInline()))
20955	return false;
20956	// FIXME: For any other kind of variable, we should build a CFG for its
20957	// initializer and check whether the context in question is reachable.
20958	}
20959
20960	Diag(Loc, PD);
20961	return true;
20962	}
20963
20964	/// Emit a diagnostic that describes an effect on the run-time behavior
20965	/// of the program being compiled.
20966	///
20967	/// This routine emits the given diagnostic when the code currently being
20968	/// type-checked is "potentially evaluated", meaning that there is a
20969	/// possibility that the code will actually be executable. Code in sizeof()
20970	/// expressions, code used only during overload resolution, etc., are not
20971	/// potentially evaluated. This routine will suppress such diagnostics or,
20972	/// in the absolutely nutty case of potentially potentially evaluated
20973	/// expressions (C++ typeid), queue the diagnostic to potentially emit it
20974	/// later.
20975	///
20976	/// This routine should be used for all diagnostics that describe the run-time
20977	/// behavior of a program, such as passing a non-POD value through an ellipsis.
20978	/// Failure to do so will likely result in spurious diagnostics or failures
20979	/// during overload resolution or within sizeof/alignof/typeof/typeid.
20980	bool Sema::DiagRuntimeBehavior(SourceLocation Loc, ArrayRef<const Stmt*> Stmts,
20981	const PartialDiagnostic &PD) {
20982
20983	if (ExprEvalContexts.back().isDiscardedStatementContext())
20984	return false;
20985
20986	switch (ExprEvalContexts.back().Context) {
20987	case ExpressionEvaluationContext::Unevaluated:
20988	case ExpressionEvaluationContext::UnevaluatedList:
20989	case ExpressionEvaluationContext::UnevaluatedAbstract:
20990	case ExpressionEvaluationContext::DiscardedStatement:
20991	// The argument will never be evaluated, so don't complain.
20992	break;
20993
20994	case ExpressionEvaluationContext::ConstantEvaluated:
20995	case ExpressionEvaluationContext::ImmediateFunctionContext:
20996	// Relevant diagnostics should be produced by constant evaluation.
20997	break;
20998
20999	case ExpressionEvaluationContext::PotentiallyEvaluated:
21000	case ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
21001	return DiagIfReachable(Loc, Stmts, PD);
21002	}
21003
21004	return false;
21005	}
21006
21007	bool Sema::DiagRuntimeBehavior(SourceLocation Loc, const Stmt *Statement,
21008	const PartialDiagnostic &PD) {
21009	return DiagRuntimeBehavior(
21010	Loc, Stmts: Statement ? llvm::ArrayRef(Statement) : std::nullopt, PD);
21011	}
21012
21013	bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc,
21014	CallExpr *CE, FunctionDecl *FD) {
21015	if (ReturnType->isVoidType() || !ReturnType->isIncompleteType())
21016	return false;
21017
21018	// If we're inside a decltype's expression, don't check for a valid return
21019	// type or construct temporaries until we know whether this is the last call.
21020	if (ExprEvalContexts.back().ExprContext ==
21021	ExpressionEvaluationContextRecord::EK_Decltype) {
21022	ExprEvalContexts.back().DelayedDecltypeCalls.push_back(Elt: CE);
21023	return false;
21024	}
21025
21026	class CallReturnIncompleteDiagnoser : public TypeDiagnoser {
21027	FunctionDecl *FD;
21028	CallExpr *CE;
21029
21030	public:
21031	CallReturnIncompleteDiagnoser(FunctionDecl *FD, CallExpr *CE)
21032	: FD(FD), CE(CE) { }
21033
21034	void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
21035	if (!FD) {
21036	S.Diag(Loc, diag::err_call_incomplete_return)
21037	<< T << CE->getSourceRange();
21038	return;
21039	}
21040
21041	S.Diag(Loc, diag::err_call_function_incomplete_return)
21042	<< CE->getSourceRange() << FD << T;
21043	S.Diag(FD->getLocation(), diag::note_entity_declared_at)
21044	<< FD->getDeclName();
21045	}
21046	} Diagnoser(FD, CE);
21047
21048	if (RequireCompleteType(Loc, T: ReturnType, Diagnoser))
21049	return true;
21050
21051	return false;
21052	}
21053
21054	// Diagnose the s/=/==/ and s/\|=/!=/ typos. Note that adding parentheses
21055	// will prevent this condition from triggering, which is what we want.
21056	void Sema::DiagnoseAssignmentAsCondition(Expr *E) {
21057	SourceLocation Loc;
21058
21059	unsigned diagnostic = diag::warn_condition_is_assignment;
21060	bool IsOrAssign = false;
21061
21062	if (BinaryOperator *Op = dyn_cast<BinaryOperator>(Val: E)) {
21063	if (Op->getOpcode() != BO_Assign && Op->getOpcode() != BO_OrAssign)
21064	return;
21065
21066	IsOrAssign = Op->getOpcode() == BO_OrAssign;
21067
21068	// Greylist some idioms by putting them into a warning subcategory.
21069	if (ObjCMessageExpr *ME
21070	= dyn_cast<ObjCMessageExpr>(Val: Op->getRHS()->IgnoreParenCasts())) {
21071	Selector Sel = ME->getSelector();
21072
21073	// self = [<foo> init...]
21074	if (isSelfExpr(Op->getLHS()) && ME->getMethodFamily() == OMF_init)
21075	diagnostic = diag::warn_condition_is_idiomatic_assignment;
21076
21077	// <foo> = [<bar> nextObject]
21078	else if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "nextObject")
21079	diagnostic = diag::warn_condition_is_idiomatic_assignment;
21080	}
21081
21082	Loc = Op->getOperatorLoc();
21083	} else if (CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(Val: E)) {
21084	if (Op->getOperator() != OO_Equal && Op->getOperator() != OO_PipeEqual)
21085	return;
21086
21087	IsOrAssign = Op->getOperator() == OO_PipeEqual;
21088	Loc = Op->getOperatorLoc();
21089	} else if (PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(Val: E))
21090	return DiagnoseAssignmentAsCondition(E: POE->getSyntacticForm());
21091	else {
21092	// Not an assignment.
21093	return;
21094	}
21095
21096	Diag(Loc, DiagID: diagnostic) << E->getSourceRange();
21097
21098	SourceLocation Open = E->getBeginLoc();
21099	SourceLocation Close = getLocForEndOfToken(Loc: E->getSourceRange().getEnd());
21100	Diag(Loc, diag::note_condition_assign_silence)
21101	<< FixItHint::CreateInsertion(Open, "(")
21102	<< FixItHint::CreateInsertion(Close, ")");
21103
21104	if (IsOrAssign)
21105	Diag(Loc, diag::note_condition_or_assign_to_comparison)
21106	<< FixItHint::CreateReplacement(Loc, "!=");
21107	else
21108	Diag(Loc, diag::note_condition_assign_to_comparison)
21109	<< FixItHint::CreateReplacement(Loc, "==");
21110	}
21111
21112	/// Redundant parentheses over an equality comparison can indicate
21113	/// that the user intended an assignment used as condition.
21114	void Sema::DiagnoseEqualityWithExtraParens(ParenExpr *ParenE) {
21115	// Don't warn if the parens came from a macro.
21116	SourceLocation parenLoc = ParenE->getBeginLoc();
21117	if (parenLoc.isInvalid() || parenLoc.isMacroID())
21118	return;
21119	// Don't warn for dependent expressions.
21120	if (ParenE->isTypeDependent())
21121	return;
21122
21123	Expr *E = ParenE->IgnoreParens();
21124
21125	if (BinaryOperator *opE = dyn_cast<BinaryOperator>(Val: E))
21126	if (opE->getOpcode() == BO_EQ &&
21127	opE->getLHS()->IgnoreParenImpCasts()->isModifiableLvalue(Ctx&: Context)
21128	== Expr::MLV_Valid) {
21129	SourceLocation Loc = opE->getOperatorLoc();
21130
21131	Diag(Loc, diag::warn_equality_with_extra_parens) << E->getSourceRange();
21132	SourceRange ParenERange = ParenE->getSourceRange();
21133	Diag(Loc, diag::note_equality_comparison_silence)
21134	<< FixItHint::CreateRemoval(ParenERange.getBegin())
21135	<< FixItHint::CreateRemoval(ParenERange.getEnd());
21136	Diag(Loc, diag::note_equality_comparison_to_assign)
21137	<< FixItHint::CreateReplacement(Loc, "=");
21138	}
21139	}
21140
21141	ExprResult Sema::CheckBooleanCondition(SourceLocation Loc, Expr *E,
21142	bool IsConstexpr) {
21143	DiagnoseAssignmentAsCondition(E);
21144	if (ParenExpr *parenE = dyn_cast<ParenExpr>(Val: E))
21145	DiagnoseEqualityWithExtraParens(ParenE: parenE);
21146
21147	ExprResult result = CheckPlaceholderExpr(E);
21148	if (result.isInvalid()) return ExprError();
21149	E = result.get();
21150
21151	if (!E->isTypeDependent()) {
21152	if (getLangOpts().CPlusPlus)
21153	return CheckCXXBooleanCondition(CondExpr: E, IsConstexpr); // C++ 6.4p4
21154
21155	ExprResult ERes = DefaultFunctionArrayLvalueConversion(E);
21156	if (ERes.isInvalid())
21157	return ExprError();
21158	E = ERes.get();
21159
21160	QualType T = E->getType();
21161	if (!T->isScalarType()) { // C99 6.8.4.1p1
21162	Diag(Loc, diag::err_typecheck_statement_requires_scalar)
21163	<< T << E->getSourceRange();
21164	return ExprError();
21165	}
21166	CheckBoolLikeConversion(E, CC: Loc);
21167	}
21168
21169	return E;
21170	}
21171
21172	Sema::ConditionResult Sema::ActOnCondition(Scope *S, SourceLocation Loc,
21173	Expr *SubExpr, ConditionKind CK,
21174	bool MissingOK) {
21175	// MissingOK indicates whether having no condition expression is valid
21176	// (for loop) or invalid (e.g. while loop).
21177	if (!SubExpr)
21178	return MissingOK ? ConditionResult() : ConditionError();
21179
21180	ExprResult Cond;
21181	switch (CK) {
21182	case ConditionKind::Boolean:
21183	Cond = CheckBooleanCondition(Loc, E: SubExpr);
21184	break;
21185
21186	case ConditionKind::ConstexprIf:
21187	Cond = CheckBooleanCondition(Loc, E: SubExpr, IsConstexpr: true);
21188	break;
21189
21190	case ConditionKind::Switch:
21191	Cond = CheckSwitchCondition(SwitchLoc: Loc, Cond: SubExpr);
21192	break;
21193	}
21194	if (Cond.isInvalid()) {
21195	Cond = CreateRecoveryExpr(Begin: SubExpr->getBeginLoc(), End: SubExpr->getEndLoc(),
21196	SubExprs: {SubExpr}, T: PreferredConditionType(K: CK));
21197	if (!Cond.get())
21198	return ConditionError();
21199	}
21200	// FIXME: FullExprArg doesn't have an invalid bit, so check nullness instead.
21201	FullExprArg FullExpr = MakeFullExpr(Arg: Cond.get(), CC: Loc);
21202	if (!FullExpr.get())
21203	return ConditionError();
21204
21205	return ConditionResult(*this, nullptr, FullExpr,
21206	CK == ConditionKind::ConstexprIf);
21207	}
21208
21209	namespace {
21210	/// A visitor for rebuilding a call to an __unknown_any expression
21211	/// to have an appropriate type.
21212	struct RebuildUnknownAnyFunction
21213	: StmtVisitor<RebuildUnknownAnyFunction, ExprResult> {
21214
21215	Sema &S;
21216
21217	RebuildUnknownAnyFunction(Sema &S) : S(S) {}
21218
21219	ExprResult VisitStmt(Stmt *S) {
21220	llvm_unreachable("unexpected statement!");
21221	}
21222
21223	ExprResult VisitExpr(Expr *E) {
21224	S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_call)
21225	<< E->getSourceRange();
21226	return ExprError();
21227	}
21228
21229	/// Rebuild an expression which simply semantically wraps another
21230	/// expression which it shares the type and value kind of.
21231	template <class T> ExprResult rebuildSugarExpr(T *E) {
21232	ExprResult SubResult = Visit(E->getSubExpr());
21233	if (SubResult.isInvalid()) return ExprError();
21234
21235	Expr *SubExpr = SubResult.get();
21236	E->setSubExpr(SubExpr);
21237	E->setType(SubExpr->getType());
21238	E->setValueKind(SubExpr->getValueKind());
21239	assert(E->getObjectKind() == OK_Ordinary);
21240	return E;
21241	}
21242
21243	ExprResult VisitParenExpr(ParenExpr *E) {
21244	return rebuildSugarExpr(E);
21245	}
21246
21247	ExprResult VisitUnaryExtension(UnaryOperator *E) {
21248	return rebuildSugarExpr(E);
21249	}
21250
21251	ExprResult VisitUnaryAddrOf(UnaryOperator *E) {
21252	ExprResult SubResult = Visit(E->getSubExpr());
21253	if (SubResult.isInvalid()) return ExprError();
21254
21255	Expr *SubExpr = SubResult.get();
21256	E->setSubExpr(SubExpr);
21257	E->setType(S.Context.getPointerType(T: SubExpr->getType()));
21258	assert(E->isPRValue());
21259	assert(E->getObjectKind() == OK_Ordinary);
21260	return E;
21261	}
21262
21263	ExprResult resolveDecl(Expr *E, ValueDecl *VD) {
21264	if (!isa<FunctionDecl>(Val: VD)) return VisitExpr(E);
21265
21266	E->setType(VD->getType());
21267
21268	assert(E->isPRValue());
21269	if (S.getLangOpts().CPlusPlus &&
21270	!(isa<CXXMethodDecl>(Val: VD) &&
21271	cast<CXXMethodDecl>(Val: VD)->isInstance()))
21272	E->setValueKind(VK_LValue);
21273
21274	return E;
21275	}
21276
21277	ExprResult VisitMemberExpr(MemberExpr *E) {
21278	return resolveDecl(E, E->getMemberDecl());
21279	}
21280
21281	ExprResult VisitDeclRefExpr(DeclRefExpr *E) {
21282	return resolveDecl(E, E->getDecl());
21283	}
21284	};
21285	}
21286
21287	/// Given a function expression of unknown-any type, try to rebuild it
21288	/// to have a function type.
21289	static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *FunctionExpr) {
21290	ExprResult Result = RebuildUnknownAnyFunction(S).Visit(FunctionExpr);
21291	if (Result.isInvalid()) return ExprError();
21292	return S.DefaultFunctionArrayConversion(E: Result.get());
21293	}
21294
21295	namespace {
21296	/// A visitor for rebuilding an expression of type __unknown_anytype
21297	/// into one which resolves the type directly on the referring
21298	/// expression. Strict preservation of the original source
21299	/// structure is not a goal.
21300	struct RebuildUnknownAnyExpr
21301	: StmtVisitor<RebuildUnknownAnyExpr, ExprResult> {
21302
21303	Sema &S;
21304
21305	/// The current destination type.
21306	QualType DestType;
21307
21308	RebuildUnknownAnyExpr(Sema &S, QualType CastType)
21309	: S(S), DestType(CastType) {}
21310
21311	ExprResult VisitStmt(Stmt *S) {
21312	llvm_unreachable("unexpected statement!");
21313	}
21314
21315	ExprResult VisitExpr(Expr *E) {
21316	S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr)
21317	<< E->getSourceRange();
21318	return ExprError();
21319	}
21320
21321	ExprResult VisitCallExpr(CallExpr *E);
21322	ExprResult VisitObjCMessageExpr(ObjCMessageExpr *E);
21323
21324	/// Rebuild an expression which simply semantically wraps another
21325	/// expression which it shares the type and value kind of.
21326	template <class T> ExprResult rebuildSugarExpr(T *E) {
21327	ExprResult SubResult = Visit(E->getSubExpr());
21328	if (SubResult.isInvalid()) return ExprError();
21329	Expr *SubExpr = SubResult.get();
21330	E->setSubExpr(SubExpr);
21331	E->setType(SubExpr->getType());
21332	E->setValueKind(SubExpr->getValueKind());
21333	assert(E->getObjectKind() == OK_Ordinary);
21334	return E;
21335	}
21336
21337	ExprResult VisitParenExpr(ParenExpr *E) {
21338	return rebuildSugarExpr(E);
21339	}
21340
21341	ExprResult VisitUnaryExtension(UnaryOperator *E) {
21342	return rebuildSugarExpr(E);
21343	}
21344
21345	ExprResult VisitUnaryAddrOf(UnaryOperator *E) {
21346	const PointerType *Ptr = DestType->getAs<PointerType>();
21347	if (!Ptr) {
21348	S.Diag(E->getOperatorLoc(), diag::err_unknown_any_addrof)
21349	<< E->getSourceRange();
21350	return ExprError();
21351	}
21352
21353	if (isa<CallExpr>(Val: E->getSubExpr())) {
21354	S.Diag(E->getOperatorLoc(), diag::err_unknown_any_addrof_call)
21355	<< E->getSourceRange();
21356	return ExprError();
21357	}
21358
21359	assert(E->isPRValue());
21360	assert(E->getObjectKind() == OK_Ordinary);
21361	E->setType(DestType);
21362
21363	// Build the sub-expression as if it were an object of the pointee type.
21364	DestType = Ptr->getPointeeType();
21365	ExprResult SubResult = Visit(E->getSubExpr());
21366	if (SubResult.isInvalid()) return ExprError();
21367	E->setSubExpr(SubResult.get());
21368	return E;
21369	}
21370
21371	ExprResult VisitImplicitCastExpr(ImplicitCastExpr *E);
21372
21373	ExprResult resolveDecl(Expr *E, ValueDecl *VD);
21374
21375	ExprResult VisitMemberExpr(MemberExpr *E) {
21376	return resolveDecl(E, E->getMemberDecl());
21377	}
21378
21379	ExprResult VisitDeclRefExpr(DeclRefExpr *E) {
21380	return resolveDecl(E, E->getDecl());
21381	}
21382	};
21383	}
21384
21385	/// Rebuilds a call expression which yielded __unknown_anytype.
21386	ExprResult RebuildUnknownAnyExpr::VisitCallExpr(CallExpr *E) {
21387	Expr *CalleeExpr = E->getCallee();
21388
21389	enum FnKind {
21390	FK_MemberFunction,
21391	FK_FunctionPointer,
21392	FK_BlockPointer
21393	};
21394
21395	FnKind Kind;
21396	QualType CalleeType = CalleeExpr->getType();
21397	if (CalleeType == S.Context.BoundMemberTy) {
21398	assert(isa<CXXMemberCallExpr>(E) || isa<CXXOperatorCallExpr>(E));
21399	Kind = FK_MemberFunction;
21400	CalleeType = Expr::findBoundMemberType(expr: CalleeExpr);
21401	} else if (const PointerType *Ptr = CalleeType->getAs<PointerType>()) {
21402	CalleeType = Ptr->getPointeeType();
21403	Kind = FK_FunctionPointer;
21404	} else {
21405	CalleeType = CalleeType->castAs<BlockPointerType>()->getPointeeType();
21406	Kind = FK_BlockPointer;
21407	}
21408	const FunctionType *FnType = CalleeType->castAs<FunctionType>();
21409
21410	// Verify that this is a legal result type of a function.
21411	if (DestType->isArrayType() || DestType->isFunctionType()) {
21412	unsigned diagID = diag::err_func_returning_array_function;
21413	if (Kind == FK_BlockPointer)
21414	diagID = diag::err_block_returning_array_function;
21415
21416	S.Diag(E->getExprLoc(), diagID)
21417	<< DestType->isFunctionType() << DestType;
21418	return ExprError();
21419	}
21420
21421	// Otherwise, go ahead and set DestType as the call's result.
21422	E->setType(DestType.getNonLValueExprType(S.Context));
21423	E->setValueKind(Expr::getValueKindForType(DestType));
21424	assert(E->getObjectKind() == OK_Ordinary);
21425
21426	// Rebuild the function type, replacing the result type with DestType.
21427	const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(Val: FnType);
21428	if (Proto) {
21429	// __unknown_anytype(...) is a special case used by the debugger when
21430	// it has no idea what a function's signature is.
21431	//
21432	// We want to build this call essentially under the K&R
21433	// unprototyped rules, but making a FunctionNoProtoType in C++
21434	// would foul up all sorts of assumptions. However, we cannot
21435	// simply pass all arguments as variadic arguments, nor can we
21436	// portably just call the function under a non-variadic type; see
21437	// the comment on IR-gen's TargetInfo::isNoProtoCallVariadic.
21438	// However, it turns out that in practice it is generally safe to
21439	// call a function declared as "A foo(B,C,D);" under the prototype
21440	// "A foo(B,C,D,...);". The only known exception is with the
21441	// Windows ABI, where any variadic function is implicitly cdecl
21442	// regardless of its normal CC. Therefore we change the parameter
21443	// types to match the types of the arguments.
21444	//
21445	// This is a hack, but it is far superior to moving the
21446	// corresponding target-specific code from IR-gen to Sema/AST.
21447
21448	ArrayRef<QualType> ParamTypes = Proto->getParamTypes();
21449	SmallVector<QualType, 8> ArgTypes;
21450	if (ParamTypes.empty() && Proto->isVariadic()) { // the special case
21451	ArgTypes.reserve(N: E->getNumArgs());
21452	for (unsigned i = 0, e = E->getNumArgs(); i != e; ++i) {
21453	ArgTypes.push_back(Elt: S.Context.getReferenceQualifiedType(e: E->getArg(Arg: i)));
21454	}
21455	ParamTypes = ArgTypes;
21456	}
21457	DestType = S.Context.getFunctionType(DestType, ParamTypes,
21458	Proto->getExtProtoInfo());
21459	} else {
21460	DestType = S.Context.getFunctionNoProtoType(DestType,
21461	FnType->getExtInfo());
21462	}
21463
21464	// Rebuild the appropriate pointer-to-function type.
21465	switch (Kind) {
21466	case FK_MemberFunction:
21467	// Nothing to do.
21468	break;
21469
21470	case FK_FunctionPointer:
21471	DestType = S.Context.getPointerType(DestType);
21472	break;
21473
21474	case FK_BlockPointer:
21475	DestType = S.Context.getBlockPointerType(DestType);
21476	break;
21477	}
21478
21479	// Finally, we can recurse.
21480	ExprResult CalleeResult = Visit(CalleeExpr);
21481	if (!CalleeResult.isUsable()) return ExprError();
21482	E->setCallee(CalleeResult.get());
21483
21484	// Bind a temporary if necessary.
21485	return S.MaybeBindToTemporary(E);
21486	}
21487
21488	ExprResult RebuildUnknownAnyExpr::VisitObjCMessageExpr(ObjCMessageExpr *E) {
21489	// Verify that this is a legal result type of a call.
21490	if (DestType->isArrayType() || DestType->isFunctionType()) {
21491	S.Diag(E->getExprLoc(), diag::err_func_returning_array_function)
21492	<< DestType->isFunctionType() << DestType;
21493	return ExprError();
21494	}
21495
21496	// Rewrite the method result type if available.
21497	if (ObjCMethodDecl *Method = E->getMethodDecl()) {
21498	assert(Method->getReturnType() == S.Context.UnknownAnyTy);
21499	Method->setReturnType(DestType);
21500	}
21501
21502	// Change the type of the message.
21503	E->setType(DestType.getNonReferenceType());
21504	E->setValueKind(Expr::getValueKindForType(DestType));
21505
21506	return S.MaybeBindToTemporary(E);
21507	}
21508
21509	ExprResult RebuildUnknownAnyExpr::VisitImplicitCastExpr(ImplicitCastExpr *E) {
21510	// The only case we should ever see here is a function-to-pointer decay.
21511	if (E->getCastKind() == CK_FunctionToPointerDecay) {
21512	assert(E->isPRValue());
21513	assert(E->getObjectKind() == OK_Ordinary);
21514
21515	E->setType(DestType);
21516
21517	// Rebuild the sub-expression as the pointee (function) type.
21518	DestType = DestType->castAs<PointerType>()->getPointeeType();
21519
21520	ExprResult Result = Visit(E->getSubExpr());
21521	if (!Result.isUsable()) return ExprError();
21522
21523	E->setSubExpr(Result.get());
21524	return E;
21525	} else if (E->getCastKind() == CK_LValueToRValue) {
21526	assert(E->isPRValue());
21527	assert(E->getObjectKind() == OK_Ordinary);
21528
21529	assert(isa<BlockPointerType>(E->getType()));
21530
21531	E->setType(DestType);
21532
21533	// The sub-expression has to be a lvalue reference, so rebuild it as such.
21534	DestType = S.Context.getLValueReferenceType(DestType);
21535
21536	ExprResult Result = Visit(E->getSubExpr());
21537	if (!Result.isUsable()) return ExprError();
21538
21539	E->setSubExpr(Result.get());
21540	return E;
21541	} else {
21542	llvm_unreachable("Unhandled cast type!");
21543	}
21544	}
21545
21546	ExprResult RebuildUnknownAnyExpr::resolveDecl(Expr *E, ValueDecl *VD) {
21547	ExprValueKind ValueKind = VK_LValue;
21548	QualType Type = DestType;
21549
21550	// We know how to make this work for certain kinds of decls:
21551
21552	// - functions
21553	if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Val: VD)) {
21554	if (const PointerType *Ptr = Type->getAs<PointerType>()) {
21555	DestType = Ptr->getPointeeType();
21556	ExprResult Result = resolveDecl(E, VD);
21557	if (Result.isInvalid()) return ExprError();
21558	return S.ImpCastExprToType(E: Result.get(), Type, CK: CK_FunctionToPointerDecay,
21559	VK: VK_PRValue);
21560	}
21561
21562	if (!Type->isFunctionType()) {
21563	S.Diag(E->getExprLoc(), diag::err_unknown_any_function)
21564	<< VD << E->getSourceRange();
21565	return ExprError();
21566	}
21567	if (const FunctionProtoType *FT = Type->getAs<FunctionProtoType>()) {
21568	// We must match the FunctionDecl's type to the hack introduced in
21569	// RebuildUnknownAnyExpr::VisitCallExpr to vararg functions of unknown
21570	// type. See the lengthy commentary in that routine.
21571	QualType FDT = FD->getType();
21572	const FunctionType *FnType = FDT->castAs<FunctionType>();
21573	const FunctionProtoType *Proto = dyn_cast_or_null<FunctionProtoType>(Val: FnType);
21574	DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: E);
21575	if (DRE && Proto && Proto->getParamTypes().empty() && Proto->isVariadic()) {
21576	SourceLocation Loc = FD->getLocation();
21577	FunctionDecl *NewFD = FunctionDecl::Create(
21578	S.Context, FD->getDeclContext(), Loc, Loc,
21579	FD->getNameInfo().getName(), DestType, FD->getTypeSourceInfo(),
21580	SC_None, S.getCurFPFeatures().isFPConstrained(),
21581	false /*isInlineSpecified*/, FD->hasPrototype(),
21582	/*ConstexprKind*/ ConstexprSpecKind::Unspecified);
21583
21584	if (FD->getQualifier())
21585	NewFD->setQualifierInfo(FD->getQualifierLoc());
21586
21587	SmallVector<ParmVarDecl*, 16> Params;
21588	for (const auto &AI : FT->param_types()) {
21589	ParmVarDecl *Param =
21590	S.BuildParmVarDeclForTypedef(FD, Loc, AI);
21591	Param->setScopeInfo(scopeDepth: 0, parameterIndex: Params.size());
21592	Params.push_back(Elt: Param);
21593	}
21594	NewFD->setParams(Params);
21595	DRE->setDecl(NewFD);
21596	VD = DRE->getDecl();
21597	}
21598	}
21599
21600	if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Val: FD))
21601	if (MD->isInstance()) {
21602	ValueKind = VK_PRValue;
21603	Type = S.Context.BoundMemberTy;
21604	}
21605
21606	// Function references aren't l-values in C.
21607	if (!S.getLangOpts().CPlusPlus)
21608	ValueKind = VK_PRValue;
21609
21610	// - variables
21611	} else if (isa<VarDecl>(Val: VD)) {
21612	if (const ReferenceType *RefTy = Type->getAs<ReferenceType>()) {
21613	Type = RefTy->getPointeeType();
21614	} else if (Type->isFunctionType()) {
21615	S.Diag(E->getExprLoc(), diag::err_unknown_any_var_function_type)
21616	<< VD << E->getSourceRange();
21617	return ExprError();
21618	}
21619
21620	// - nothing else
21621	} else {
21622	S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_decl)
21623	<< VD << E->getSourceRange();
21624	return ExprError();
21625	}
21626
21627	// Modifying the declaration like this is friendly to IR-gen but
21628	// also really dangerous.
21629	VD->setType(DestType);
21630	E->setType(Type);
21631	E->setValueKind(ValueKind);
21632	return E;
21633	}
21634
21635	/// Check a cast of an unknown-any type. We intentionally only
21636	/// trigger this for C-style casts.
21637	ExprResult Sema::checkUnknownAnyCast(SourceRange TypeRange, QualType CastType,
21638	Expr *CastExpr, CastKind &CastKind,
21639	ExprValueKind &VK, CXXCastPath &Path) {
21640	// The type we're casting to must be either void or complete.
21641	if (!CastType->isVoidType() &&
21642	RequireCompleteType(TypeRange.getBegin(), CastType,
21643	diag::err_typecheck_cast_to_incomplete))
21644	return ExprError();
21645
21646	// Rewrite the casted expression from scratch.
21647	ExprResult result = RebuildUnknownAnyExpr(*this, CastType).Visit(CastExpr);
21648	if (!result.isUsable()) return ExprError();
21649
21650	CastExpr = result.get();
21651	VK = CastExpr->getValueKind();
21652	CastKind = CK_NoOp;
21653
21654	return CastExpr;
21655	}
21656
21657	ExprResult Sema::forceUnknownAnyToType(Expr *E, QualType ToType) {
21658	return RebuildUnknownAnyExpr(*this, ToType).Visit(E);
21659	}
21660
21661	ExprResult Sema::checkUnknownAnyArg(SourceLocation callLoc,
21662	Expr *arg, QualType &paramType) {
21663	// If the syntactic form of the argument is not an explicit cast of
21664	// any sort, just do default argument promotion.
21665	ExplicitCastExpr *castArg = dyn_cast<ExplicitCastExpr>(Val: arg->IgnoreParens());
21666	if (!castArg) {
21667	ExprResult result = DefaultArgumentPromotion(E: arg);
21668	if (result.isInvalid()) return ExprError();
21669	paramType = result.get()->getType();
21670	return result;
21671	}
21672
21673	// Otherwise, use the type that was written in the explicit cast.
21674	assert(!arg->hasPlaceholderType());
21675	paramType = castArg->getTypeAsWritten();
21676
21677	// Copy-initialize a parameter of that type.
21678	InitializedEntity entity =
21679	InitializedEntity::InitializeParameter(Context, Type: paramType,
21680	/*consumed*/ Consumed: false);
21681	return PerformCopyInitialization(Entity: entity, EqualLoc: callLoc, Init: arg);
21682	}
21683
21684	static ExprResult diagnoseUnknownAnyExpr(Sema &S, Expr *E) {
21685	Expr *orig = E;
21686	unsigned diagID = diag::err_uncasted_use_of_unknown_any;
21687	while (true) {
21688	E = E->IgnoreParenImpCasts();
21689	if (CallExpr *call = dyn_cast<CallExpr>(Val: E)) {
21690	E = call->getCallee();
21691	diagID = diag::err_uncasted_call_of_unknown_any;
21692	} else {
21693	break;
21694	}
21695	}
21696
21697	SourceLocation loc;
21698	NamedDecl *d;
21699	if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(Val: E)) {
21700	loc = ref->getLocation();
21701	d = ref->getDecl();
21702	} else if (MemberExpr *mem = dyn_cast<MemberExpr>(Val: E)) {
21703	loc = mem->getMemberLoc();
21704	d = mem->getMemberDecl();
21705	} else if (ObjCMessageExpr *msg = dyn_cast<ObjCMessageExpr>(Val: E)) {
21706	diagID = diag::err_uncasted_call_of_unknown_any;
21707	loc = msg->getSelectorStartLoc();
21708	d = msg->getMethodDecl();
21709	if (!d) {
21710	S.Diag(loc, diag::err_uncasted_send_to_unknown_any_method)
21711	<< static_cast<unsigned>(msg->isClassMessage()) << msg->getSelector()
21712	<< orig->getSourceRange();
21713	return ExprError();
21714	}
21715	} else {
21716	S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr)
21717	<< E->getSourceRange();
21718	return ExprError();
21719	}
21720
21721	S.Diag(Loc: loc, DiagID: diagID) << d << orig->getSourceRange();
21722
21723	// Never recoverable.
21724	return ExprError();
21725	}
21726
21727	/// Check for operands with placeholder types and complain if found.
21728	/// Returns ExprError() if there was an error and no recovery was possible.
21729	ExprResult Sema::CheckPlaceholderExpr(Expr *E) {
21730	if (!Context.isDependenceAllowed()) {
21731	// C cannot handle TypoExpr nodes on either side of a binop because it
21732	// doesn't handle dependent types properly, so make sure any TypoExprs have
21733	// been dealt with before checking the operands.
21734	ExprResult Result = CorrectDelayedTyposInExpr(E);
21735	if (!Result.isUsable()) return ExprError();
21736	E = Result.get();
21737	}
21738
21739	const BuiltinType *placeholderType = E->getType()->getAsPlaceholderType();
21740	if (!placeholderType) return E;
21741
21742	switch (placeholderType->getKind()) {
21743
21744	// Overloaded expressions.
21745	case BuiltinType::Overload: {
21746	// Try to resolve a single function template specialization.
21747	// This is obligatory.
21748	ExprResult Result = E;
21749	if (ResolveAndFixSingleFunctionTemplateSpecialization(SrcExpr&: Result, DoFunctionPointerConversion: false))
21750	return Result;
21751
21752	// No guarantees that ResolveAndFixSingleFunctionTemplateSpecialization
21753	// leaves Result unchanged on failure.
21754	Result = E;
21755	if (resolveAndFixAddressOfSingleOverloadCandidate(SrcExpr&: Result))
21756	return Result;
21757
21758	// If that failed, try to recover with a call.
21759	tryToRecoverWithCall(Result, PDiag(diag::err_ovl_unresolvable),
21760	/*complain*/ true);
21761	return Result;
21762	}
21763
21764	// Bound member functions.
21765	case BuiltinType::BoundMember: {
21766	ExprResult result = E;
21767	const Expr *BME = E->IgnoreParens();
21768	PartialDiagnostic PD = PDiag(diag::err_bound_member_function);
21769	// Try to give a nicer diagnostic if it is a bound member that we recognize.
21770	if (isa<CXXPseudoDestructorExpr>(Val: BME)) {
21771	PD = PDiag(diag::err_dtor_expr_without_call) << /*pseudo-destructor*/ 1;
21772	} else if (const auto *ME = dyn_cast<MemberExpr>(Val: BME)) {
21773	if (ME->getMemberNameInfo().getName().getNameKind() ==
21774	DeclarationName::CXXDestructorName)
21775	PD = PDiag(diag::err_dtor_expr_without_call) << /*destructor*/ 0;
21776	}
21777	tryToRecoverWithCall(E&: result, PD,
21778	/*complain*/ ForceComplain: true);
21779	return result;
21780	}
21781
21782	// ARC unbridged casts.
21783	case BuiltinType::ARCUnbridgedCast: {
21784	Expr *realCast = stripARCUnbridgedCast(e: E);
21785	diagnoseARCUnbridgedCast(e: realCast);
21786	return realCast;
21787	}
21788
21789	// Expressions of unknown type.
21790	case BuiltinType::UnknownAny:
21791	return diagnoseUnknownAnyExpr(S&: *this, E);
21792
21793	// Pseudo-objects.
21794	case BuiltinType::PseudoObject:
21795	return checkPseudoObjectRValue(E);
21796
21797	case BuiltinType::BuiltinFn: {
21798	// Accept __noop without parens by implicitly converting it to a call expr.
21799	auto *DRE = dyn_cast<DeclRefExpr>(Val: E->IgnoreParenImpCasts());
21800	if (DRE) {
21801	auto *FD = cast<FunctionDecl>(Val: DRE->getDecl());
21802	unsigned BuiltinID = FD->getBuiltinID();
21803	if (BuiltinID == Builtin::BI__noop) {
21804	E = ImpCastExprToType(E, Type: Context.getPointerType(FD->getType()),
21805	CK: CK_BuiltinFnToFnPtr)
21806	.get();
21807	return CallExpr::Create(Ctx: Context, Fn: E, /*Args=*/{}, Ty: Context.IntTy,
21808	VK: VK_PRValue, RParenLoc: SourceLocation(),
21809	FPFeatures: FPOptionsOverride());
21810	}
21811
21812	if (Context.BuiltinInfo.isInStdNamespace(ID: BuiltinID)) {
21813	// Any use of these other than a direct call is ill-formed as of C++20,
21814	// because they are not addressable functions. In earlier language
21815	// modes, warn and force an instantiation of the real body.
21816	Diag(E->getBeginLoc(),
21817	getLangOpts().CPlusPlus20
21818	? diag::err_use_of_unaddressable_function
21819	: diag::warn_cxx20_compat_use_of_unaddressable_function);
21820	if (FD->isImplicitlyInstantiable()) {
21821	// Require a definition here because a normal attempt at
21822	// instantiation for a builtin will be ignored, and we won't try
21823	// again later. We assume that the definition of the template
21824	// precedes this use.
21825	InstantiateFunctionDefinition(PointOfInstantiation: E->getBeginLoc(), Function: FD,
21826	/*Recursive=*/false,
21827	/*DefinitionRequired=*/true,
21828	/*AtEndOfTU=*/false);
21829	}
21830	// Produce a properly-typed reference to the function.
21831	CXXScopeSpec SS;
21832	SS.Adopt(Other: DRE->getQualifierLoc());
21833	TemplateArgumentListInfo TemplateArgs;
21834	DRE->copyTemplateArgumentsInto(List&: TemplateArgs);
21835	return BuildDeclRefExpr(
21836	FD, FD->getType(), VK_LValue, DRE->getNameInfo(),
21837	DRE->hasQualifier() ? &SS : nullptr, DRE->getFoundDecl(),
21838	DRE->getTemplateKeywordLoc(),
21839	DRE->hasExplicitTemplateArgs() ? &TemplateArgs : nullptr);
21840	}
21841	}
21842
21843	Diag(E->getBeginLoc(), diag::err_builtin_fn_use);
21844	return ExprError();
21845	}
21846
21847	case BuiltinType::IncompleteMatrixIdx:
21848	Diag(cast<MatrixSubscriptExpr>(E->IgnoreParens())
21849	->getRowIdx()
21850	->getBeginLoc(),
21851	diag::err_matrix_incomplete_index);
21852	return ExprError();
21853
21854	// Expressions of unknown type.
21855	case BuiltinType::OMPArraySection:
21856	Diag(E->getBeginLoc(), diag::err_omp_array_section_use);
21857	return ExprError();
21858
21859	// Expressions of unknown type.
21860	case BuiltinType::OMPArrayShaping:
21861	return ExprError(Diag(E->getBeginLoc(), diag::err_omp_array_shaping_use));
21862
21863	case BuiltinType::OMPIterator:
21864	return ExprError(Diag(E->getBeginLoc(), diag::err_omp_iterator_use));
21865
21866	// Everything else should be impossible.
21867	#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
21868	case BuiltinType::Id:
21869	#include "clang/Basic/OpenCLImageTypes.def"
21870	#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
21871	case BuiltinType::Id:
21872	#include "clang/Basic/OpenCLExtensionTypes.def"
21873	#define SVE_TYPE(Name, Id, SingletonId) \
21874	case BuiltinType::Id:
21875	#include "clang/Basic/AArch64SVEACLETypes.def"
21876	#define PPC_VECTOR_TYPE(Name, Id, Size) \
21877	case BuiltinType::Id:
21878	#include "clang/Basic/PPCTypes.def"
21879	#define RVV_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
21880	#include "clang/Basic/RISCVVTypes.def"
21881	#define WASM_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
21882	#include "clang/Basic/WebAssemblyReferenceTypes.def"
21883	#define BUILTIN_TYPE(Id, SingletonId) case BuiltinType::Id:
21884	#define PLACEHOLDER_TYPE(Id, SingletonId)
21885	#include "clang/AST/BuiltinTypes.def"
21886	break;
21887	}
21888
21889	llvm_unreachable("invalid placeholder type!");
21890	}
21891
21892	bool Sema::CheckCaseExpression(Expr *E) {
21893	if (E->isTypeDependent())
21894	return true;
21895	if (E->isValueDependent() || E->isIntegerConstantExpr(Ctx: Context))
21896	return E->getType()->isIntegralOrEnumerationType();
21897	return false;
21898	}
21899
21900	/// ActOnObjCBoolLiteral - Parse {__objc_yes,__objc_no} literals.
21901	ExprResult
21902	Sema::ActOnObjCBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
21903	assert((Kind == tok::kw___objc_yes || Kind == tok::kw___objc_no) &&
21904	"Unknown Objective-C Boolean value!");
21905	QualType BoolT = Context.ObjCBuiltinBoolTy;
21906	if (!Context.getBOOLDecl()) {
21907	LookupResult Result(*this, &Context.Idents.get(Name: "BOOL"), OpLoc,
21908	Sema::LookupOrdinaryName);
21909	if (LookupName(R&: Result, S: getCurScope()) && Result.isSingleResult()) {
21910	NamedDecl *ND = Result.getFoundDecl();
21911	if (TypedefDecl *TD = dyn_cast<TypedefDecl>(Val: ND))
21912	Context.setBOOLDecl(TD);
21913	}
21914	}
21915	if (Context.getBOOLDecl())
21916	BoolT = Context.getBOOLType();
21917	return new (Context)
21918	ObjCBoolLiteralExpr(Kind == tok::kw___objc_yes, BoolT, OpLoc);
21919	}
21920
21921	ExprResult Sema::ActOnObjCAvailabilityCheckExpr(
21922	llvm::ArrayRef<AvailabilitySpec> AvailSpecs, SourceLocation AtLoc,
21923	SourceLocation RParen) {
21924	auto FindSpecVersion =
21925	[&](StringRef Platform) -> std::optional<VersionTuple> {
21926	auto Spec = llvm::find_if(Range&: AvailSpecs, P: [&](const AvailabilitySpec &Spec) {
21927	return Spec.getPlatform() == Platform;
21928	});
21929	// Transcribe the "ios" availability check to "maccatalyst" when compiling
21930	// for "maccatalyst" if "maccatalyst" is not specified.
21931	if (Spec == AvailSpecs.end() && Platform == "maccatalyst") {
21932	Spec = llvm::find_if(Range&: AvailSpecs, P: [&](const AvailabilitySpec &Spec) {
21933	return Spec.getPlatform() == "ios";
21934	});
21935	}
21936	if (Spec == AvailSpecs.end())
21937	return std::nullopt;
21938	return Spec->getVersion();
21939	};
21940
21941	VersionTuple Version;
21942	if (auto MaybeVersion =
21943	FindSpecVersion(Context.getTargetInfo().getPlatformName()))
21944	Version = *MaybeVersion;
21945
21946	// The use of `@available` in the enclosing context should be analyzed to
21947	// warn when it's used inappropriately (i.e. not if(@available)).
21948	if (FunctionScopeInfo *Context = getCurFunctionAvailabilityContext())
21949	Context->HasPotentialAvailabilityViolations = true;
21950
21951	return new (Context)
21952	ObjCAvailabilityCheckExpr(Version, AtLoc, RParen, Context.BoolTy);
21953	}
21954
21955	ExprResult Sema::CreateRecoveryExpr(SourceLocation Begin, SourceLocation End,
21956	ArrayRef<Expr *> SubExprs, QualType T) {
21957	if (!Context.getLangOpts().RecoveryAST)
21958	return ExprError();
21959
21960	if (isSFINAEContext())
21961	return ExprError();
21962
21963	if (T.isNull() || T->isUndeducedType() ||
21964	!Context.getLangOpts().RecoveryASTType)
21965	// We don't know the concrete type, fallback to dependent type.
21966	T = Context.DependentTy;
21967
21968	return RecoveryExpr::Create(Ctx&: Context, T, BeginLoc: Begin, EndLoc: End, SubExprs);
21969	}
21970