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 "CheckExprLifetime.h"
14	#include "TreeTransform.h"
15	#include "UsedDeclVisitor.h"
16	#include "clang/AST/ASTConsumer.h"
17	#include "clang/AST/ASTContext.h"
18	#include "clang/AST/ASTDiagnostic.h"
19	#include "clang/AST/ASTLambda.h"
20	#include "clang/AST/ASTMutationListener.h"
21	#include "clang/AST/CXXInheritance.h"
22	#include "clang/AST/Decl.h"
23	#include "clang/AST/DeclObjC.h"
24	#include "clang/AST/DeclTemplate.h"
25	#include "clang/AST/DynamicRecursiveASTVisitor.h"
26	#include "clang/AST/EvaluatedExprVisitor.h"
27	#include "clang/AST/Expr.h"
28	#include "clang/AST/ExprCXX.h"
29	#include "clang/AST/ExprObjC.h"
30	#include "clang/AST/MangleNumberingContext.h"
31	#include "clang/AST/OperationKinds.h"
32	#include "clang/AST/Type.h"
33	#include "clang/AST/TypeLoc.h"
34	#include "clang/Basic/Builtins.h"
35	#include "clang/Basic/DiagnosticSema.h"
36	#include "clang/Basic/PartialDiagnostic.h"
37	#include "clang/Basic/SourceManager.h"
38	#include "clang/Basic/Specifiers.h"
39	#include "clang/Basic/TargetInfo.h"
40	#include "clang/Basic/TypeTraits.h"
41	#include "clang/Lex/LiteralSupport.h"
42	#include "clang/Lex/Preprocessor.h"
43	#include "clang/Sema/AnalysisBasedWarnings.h"
44	#include "clang/Sema/DeclSpec.h"
45	#include "clang/Sema/DelayedDiagnostic.h"
46	#include "clang/Sema/Designator.h"
47	#include "clang/Sema/EnterExpressionEvaluationContext.h"
48	#include "clang/Sema/Initialization.h"
49	#include "clang/Sema/Lookup.h"
50	#include "clang/Sema/Overload.h"
51	#include "clang/Sema/ParsedTemplate.h"
52	#include "clang/Sema/Scope.h"
53	#include "clang/Sema/ScopeInfo.h"
54	#include "clang/Sema/SemaARM.h"
55	#include "clang/Sema/SemaCUDA.h"
56	#include "clang/Sema/SemaFixItUtils.h"
57	#include "clang/Sema/SemaHLSL.h"
58	#include "clang/Sema/SemaObjC.h"
59	#include "clang/Sema/SemaOpenMP.h"
60	#include "clang/Sema/SemaPseudoObject.h"
61	#include "clang/Sema/Template.h"
62	#include "llvm/ADT/STLExtras.h"
63	#include "llvm/ADT/StringExtras.h"
64	#include "llvm/Support/ConvertUTF.h"
65	#include "llvm/Support/SaveAndRestore.h"
66	#include "llvm/Support/TimeProfiler.h"
67	#include "llvm/Support/TypeSize.h"
68	#include <limits>
69	#include <optional>
70
71	using namespace clang;
72	using namespace sema;
73
74	bool Sema::CanUseDecl(NamedDecl *D, bool TreatUnavailableAsInvalid) {
75	// See if this is an auto-typed variable whose initializer we are parsing.
76	if (ParsingInitForAutoVars.count(Ptr: D))
77	return false;
78
79	// See if this is a deleted function.
80	if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Val: D)) {
81	if (FD->isDeleted())
82	return false;
83
84	// If the function has a deduced return type, and we can't deduce it,
85	// then we can't use it either.
86	if (getLangOpts().CPlusPlus14 && FD->getReturnType()->isUndeducedType() &&
87	DeduceReturnType(FD, Loc: SourceLocation(), /*Diagnose*/ false))
88	return false;
89
90	// See if this is an aligned allocation/deallocation function that is
91	// unavailable.
92	if (TreatUnavailableAsInvalid &&
93	isUnavailableAlignedAllocationFunction(FD: *FD))
94	return false;
95	}
96
97	// See if this function is unavailable.
98	if (TreatUnavailableAsInvalid && D->getAvailability() == AR_Unavailable &&
99	cast<Decl>(Val: CurContext)->getAvailability() != AR_Unavailable)
100	return false;
101
102	if (isa<UnresolvedUsingIfExistsDecl>(Val: D))
103	return false;
104
105	return true;
106	}
107
108	static void DiagnoseUnusedOfDecl(Sema &S, NamedDecl *D, SourceLocation Loc) {
109	// Warn if this is used but marked unused.
110	if (const auto *A = D->getAttr<UnusedAttr>()) {
111	// [[maybe_unused]] should not diagnose uses, but __attribute__((unused))
112	// should diagnose them.
113	if (A->getSemanticSpelling() != UnusedAttr::CXX11_maybe_unused &&
114	A->getSemanticSpelling() != UnusedAttr::C23_maybe_unused) {
115	const Decl *DC = cast_or_null<Decl>(Val: S.ObjC().getCurObjCLexicalContext());
116	if (DC && !DC->hasAttr<UnusedAttr>())
117	S.Diag(Loc, DiagID: diag::warn_used_but_marked_unused) << D;
118	}
119	}
120	}
121
122	void Sema::NoteDeletedFunction(FunctionDecl *Decl) {
123	assert(Decl && Decl->isDeleted());
124
125	if (Decl->isDefaulted()) {
126	// If the method was explicitly defaulted, point at that declaration.
127	if (!Decl->isImplicit())
128	Diag(Loc: Decl->getLocation(), DiagID: diag::note_implicitly_deleted);
129
130	// Try to diagnose why this special member function was implicitly
131	// deleted. This might fail, if that reason no longer applies.
132	DiagnoseDeletedDefaultedFunction(FD: Decl);
133	return;
134	}
135
136	auto *Ctor = dyn_cast<CXXConstructorDecl>(Val: Decl);
137	if (Ctor && Ctor->isInheritingConstructor())
138	return NoteDeletedInheritingConstructor(CD: Ctor);
139
140	Diag(Loc: Decl->getLocation(), DiagID: diag::note_availability_specified_here)
141	<< Decl << 1;
142	}
143
144	/// Determine whether a FunctionDecl was ever declared with an
145	/// explicit storage class.
146	static bool hasAnyExplicitStorageClass(const FunctionDecl *D) {
147	for (auto *I : D->redecls()) {
148	if (I->getStorageClass() != SC_None)
149	return true;
150	}
151	return false;
152	}
153
154	/// Check whether we're in an extern inline function and referring to a
155	/// variable or function with internal linkage (C11 6.7.4p3).
156	///
157	/// This is only a warning because we used to silently accept this code, but
158	/// in many cases it will not behave correctly. This is not enabled in C++ mode
159	/// because the restriction language is a bit weaker (C++11 [basic.def.odr]p6)
160	/// and so while there may still be user mistakes, most of the time we can't
161	/// prove that there are errors.
162	static void diagnoseUseOfInternalDeclInInlineFunction(Sema &S,
163	const NamedDecl *D,
164	SourceLocation Loc) {
165	// This is disabled under C++; there are too many ways for this to fire in
166	// contexts where the warning is a false positive, or where it is technically
167	// correct but benign.
168	if (S.getLangOpts().CPlusPlus)
169	return;
170
171	// Check if this is an inlined function or method.
172	FunctionDecl *Current = S.getCurFunctionDecl();
173	if (!Current)
174	return;
175	if (!Current->isInlined())
176	return;
177	if (!Current->isExternallyVisible())
178	return;
179
180	// Check if the decl has internal linkage.
181	if (D->getFormalLinkage() != Linkage::Internal)
182	return;
183
184	// Downgrade from ExtWarn to Extension if
185	// (1) the supposedly external inline function is in the main file,
186	// and probably won't be included anywhere else.
187	// (2) the thing we're referencing is a pure function.
188	// (3) the thing we're referencing is another inline function.
189	// This last can give us false negatives, but it's better than warning on
190	// wrappers for simple C library functions.
191	const FunctionDecl *UsedFn = dyn_cast<FunctionDecl>(Val: D);
192	bool DowngradeWarning = S.getSourceManager().isInMainFile(Loc);
193	if (!DowngradeWarning && UsedFn)
194	DowngradeWarning = UsedFn->isInlined() || UsedFn->hasAttr<ConstAttr>();
195
196	S.Diag(Loc, DiagID: DowngradeWarning ? diag::ext_internal_in_extern_inline_quiet
197	: diag::ext_internal_in_extern_inline)
198	<< /*IsVar=*/!UsedFn << D;
199
200	S.MaybeSuggestAddingStaticToDecl(D: Current);
201
202	S.Diag(Loc: D->getCanonicalDecl()->getLocation(), DiagID: diag::note_entity_declared_at)
203	<< D;
204	}
205
206	void Sema::MaybeSuggestAddingStaticToDecl(const FunctionDecl *Cur) {
207	const FunctionDecl *First = Cur->getFirstDecl();
208
209	// Suggest "static" on the function, if possible.
210	if (!hasAnyExplicitStorageClass(D: First)) {
211	SourceLocation DeclBegin = First->getSourceRange().getBegin();
212	Diag(Loc: DeclBegin, DiagID: diag::note_convert_inline_to_static)
213	<< Cur << FixItHint::CreateInsertion(InsertionLoc: DeclBegin, Code: "static ");
214	}
215	}
216
217	bool Sema::DiagnoseUseOfDecl(NamedDecl *D, ArrayRef<SourceLocation> Locs,
218	const ObjCInterfaceDecl *UnknownObjCClass,
219	bool ObjCPropertyAccess,
220	bool AvoidPartialAvailabilityChecks,
221	ObjCInterfaceDecl *ClassReceiver,
222	bool SkipTrailingRequiresClause) {
223	SourceLocation Loc = Locs.front();
224	if (getLangOpts().CPlusPlus && isa<FunctionDecl>(Val: D)) {
225	// If there were any diagnostics suppressed by template argument deduction,
226	// emit them now.
227	auto Pos = SuppressedDiagnostics.find(Val: D->getCanonicalDecl());
228	if (Pos != SuppressedDiagnostics.end()) {
229	for (const auto &[DiagLoc, PD] : Pos->second) {
230	DiagnosticBuilder Builder(Diags.Report(Loc: DiagLoc, DiagID: PD.getDiagID()));
231	PD.Emit(DB: Builder);
232	}
233	// Clear out the list of suppressed diagnostics, so that we don't emit
234	// them again for this specialization. However, we don't obsolete this
235	// entry from the table, because we want to avoid ever emitting these
236	// diagnostics again.
237	Pos->second.clear();
238	}
239
240	// C++ [basic.start.main]p3:
241	// The function 'main' shall not be used within a program.
242	if (cast<FunctionDecl>(Val: D)->isMain())
243	Diag(Loc, DiagID: diag::ext_main_used);
244
245	diagnoseUnavailableAlignedAllocation(FD: *cast<FunctionDecl>(Val: D), Loc);
246	}
247
248	// See if this is an auto-typed variable whose initializer we are parsing.
249	if (ParsingInitForAutoVars.count(Ptr: D)) {
250	if (isa<BindingDecl>(Val: D)) {
251	Diag(Loc, DiagID: diag::err_binding_cannot_appear_in_own_initializer)
252	<< D->getDeclName();
253	} else {
254	Diag(Loc, DiagID: diag::err_auto_variable_cannot_appear_in_own_initializer)
255	<< diag::ParsingInitFor::Var << D->getDeclName()
256	<< cast<VarDecl>(Val: D)->getType();
257	}
258	return true;
259	}
260
261	if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Val: D)) {
262	// See if this is a deleted function.
263	if (FD->isDeleted()) {
264	auto *Ctor = dyn_cast<CXXConstructorDecl>(Val: FD);
265	if (Ctor && Ctor->isInheritingConstructor())
266	Diag(Loc, DiagID: diag::err_deleted_inherited_ctor_use)
267	<< Ctor->getParent()
268	<< Ctor->getInheritedConstructor().getConstructor()->getParent();
269	else {
270	StringLiteral *Msg = FD->getDeletedMessage();
271	Diag(Loc, DiagID: diag::err_deleted_function_use)
272	<< (Msg != nullptr) << (Msg ? Msg->getString() : StringRef());
273	}
274	NoteDeletedFunction(Decl: FD);
275	return true;
276	}
277
278	// [expr.prim.id]p4
279	// A program that refers explicitly or implicitly to a function with a
280	// trailing requires-clause whose constraint-expression is not satisfied,
281	// other than to declare it, is ill-formed. [...]
282	//
283	// See if this is a function with constraints that need to be satisfied.
284	// Check this before deducing the return type, as it might instantiate the
285	// definition.
286	if (!SkipTrailingRequiresClause && FD->getTrailingRequiresClause()) {
287	ConstraintSatisfaction Satisfaction;
288	if (CheckFunctionConstraints(FD, Satisfaction, UsageLoc: Loc,
289	/*ForOverloadResolution*/ true))
290	// A diagnostic will have already been generated (non-constant
291	// constraint expression, for example)
292	return true;
293	if (!Satisfaction.IsSatisfied) {
294	Diag(Loc,
295	DiagID: diag::err_reference_to_function_with_unsatisfied_constraints)
296	<< D;
297	DiagnoseUnsatisfiedConstraint(Satisfaction);
298	return true;
299	}
300	}
301
302	// If the function has a deduced return type, and we can't deduce it,
303	// then we can't use it either.
304	if (getLangOpts().CPlusPlus14 && FD->getReturnType()->isUndeducedType() &&
305	DeduceReturnType(FD, Loc))
306	return true;
307
308	if (getLangOpts().CUDA && !CUDA().CheckCall(Loc, Callee: FD))
309	return true;
310
311	}
312
313	if (auto *Concept = dyn_cast<ConceptDecl>(Val: D);
314	Concept && CheckConceptUseInDefinition(Concept, Loc))
315	return true;
316
317	if (auto *MD = dyn_cast<CXXMethodDecl>(Val: D)) {
318	// Lambdas are only default-constructible or assignable in C++2a onwards.
319	if (MD->getParent()->isLambda() &&
320	((isa<CXXConstructorDecl>(Val: MD) &&
321	cast<CXXConstructorDecl>(Val: MD)->isDefaultConstructor()) ||
322	MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())) {
323	Diag(Loc, DiagID: diag::warn_cxx17_compat_lambda_def_ctor_assign)
324	<< !isa<CXXConstructorDecl>(Val: MD);
325	}
326	}
327
328	auto getReferencedObjCProp = [](const NamedDecl *D) ->
329	const ObjCPropertyDecl * {
330	if (const auto *MD = dyn_cast<ObjCMethodDecl>(Val: D))
331	return MD->findPropertyDecl();
332	return nullptr;
333	};
334	if (const ObjCPropertyDecl *ObjCPDecl = getReferencedObjCProp(D)) {
335	if (diagnoseArgIndependentDiagnoseIfAttrs(ND: ObjCPDecl, Loc))
336	return true;
337	} else if (diagnoseArgIndependentDiagnoseIfAttrs(ND: D, Loc)) {
338	return true;
339	}
340
341	// [OpenMP 4.0], 2.15 declare reduction Directive, Restrictions
342	// Only the variables omp_in and omp_out are allowed in the combiner.
343	// Only the variables omp_priv and omp_orig are allowed in the
344	// initializer-clause.
345	auto *DRD = dyn_cast<OMPDeclareReductionDecl>(Val: CurContext);
346	if (LangOpts.OpenMP && DRD && !CurContext->containsDecl(D) &&
347	isa<VarDecl>(Val: D)) {
348	Diag(Loc, DiagID: diag::err_omp_wrong_var_in_declare_reduction)
349	<< getCurFunction()->HasOMPDeclareReductionCombiner;
350	Diag(Loc: D->getLocation(), DiagID: diag::note_entity_declared_at) << D;
351	return true;
352	}
353
354	// [OpenMP 5.0], 2.19.7.3. declare mapper Directive, Restrictions
355	// List-items in map clauses on this construct may only refer to the declared
356	// variable var and entities that could be referenced by a procedure defined
357	// at the same location.
358	// [OpenMP 5.2] Also allow iterator declared variables.
359	if (LangOpts.OpenMP && isa<VarDecl>(Val: D) &&
360	!OpenMP().isOpenMPDeclareMapperVarDeclAllowed(VD: cast<VarDecl>(Val: D))) {
361	Diag(Loc, DiagID: diag::err_omp_declare_mapper_wrong_var)
362	<< OpenMP().getOpenMPDeclareMapperVarName();
363	Diag(Loc: D->getLocation(), DiagID: diag::note_entity_declared_at) << D;
364	return true;
365	}
366
367	if (const auto *EmptyD = dyn_cast<UnresolvedUsingIfExistsDecl>(Val: D)) {
368	Diag(Loc, DiagID: diag::err_use_of_empty_using_if_exists);
369	Diag(Loc: EmptyD->getLocation(), DiagID: diag::note_empty_using_if_exists_here);
370	return true;
371	}
372
373	DiagnoseAvailabilityOfDecl(D, Locs, UnknownObjCClass, ObjCPropertyAccess,
374	AvoidPartialAvailabilityChecks, ClassReceiver);
375
376	DiagnoseUnusedOfDecl(S&: *this, D, Loc);
377
378	diagnoseUseOfInternalDeclInInlineFunction(S&: *this, D, Loc);
379
380	if (D->hasAttr<AvailableOnlyInDefaultEvalMethodAttr>()) {
381	if (getLangOpts().getFPEvalMethod() !=
382	LangOptions::FPEvalMethodKind::FEM_UnsetOnCommandLine &&
383	PP.getLastFPEvalPragmaLocation().isValid() &&
384	PP.getCurrentFPEvalMethod() != getLangOpts().getFPEvalMethod())
385	Diag(Loc: D->getLocation(),
386	DiagID: diag::err_type_available_only_in_default_eval_method)
387	<< D->getName();
388	}
389
390	if (auto *VD = dyn_cast<ValueDecl>(Val: D))
391	checkTypeSupport(Ty: VD->getType(), Loc, D: VD);
392
393	if (LangOpts.SYCLIsDevice ||
394	(LangOpts.OpenMP && LangOpts.OpenMPIsTargetDevice)) {
395	if (!Context.getTargetInfo().isTLSSupported())
396	if (const auto *VD = dyn_cast<VarDecl>(Val: D))
397	if (VD->getTLSKind() != VarDecl::TLS_None)
398	targetDiag(Loc: *Locs.begin(), DiagID: diag::err_thread_unsupported);
399	}
400
401	return false;
402	}
403
404	void Sema::DiagnoseSentinelCalls(const NamedDecl *D, SourceLocation Loc,
405	ArrayRef<Expr *> Args) {
406	const SentinelAttr *Attr = D->getAttr<SentinelAttr>();
407	if (!Attr)
408	return;
409
410	// The number of formal parameters of the declaration.
411	unsigned NumFormalParams;
412
413	// The kind of declaration. This is also an index into a %select in
414	// the diagnostic.
415	enum { CK_Function, CK_Method, CK_Block } CalleeKind;
416
417	if (const auto *MD = dyn_cast<ObjCMethodDecl>(Val: D)) {
418	NumFormalParams = MD->param_size();
419	CalleeKind = CK_Method;
420	} else if (const auto *FD = dyn_cast<FunctionDecl>(Val: D)) {
421	NumFormalParams = FD->param_size();
422	CalleeKind = CK_Function;
423	} else if (const auto *VD = dyn_cast<VarDecl>(Val: D)) {
424	QualType Ty = VD->getType();
425	const FunctionType *Fn = nullptr;
426	if (const auto *PtrTy = Ty->getAs<PointerType>()) {
427	Fn = PtrTy->getPointeeType()->getAs<FunctionType>();
428	if (!Fn)
429	return;
430	CalleeKind = CK_Function;
431	} else if (const auto *PtrTy = Ty->getAs<BlockPointerType>()) {
432	Fn = PtrTy->getPointeeType()->castAs<FunctionType>();
433	CalleeKind = CK_Block;
434	} else {
435	return;
436	}
437
438	if (const auto *proto = dyn_cast<FunctionProtoType>(Val: Fn))
439	NumFormalParams = proto->getNumParams();
440	else
441	NumFormalParams = 0;
442	} else {
443	return;
444	}
445
446	// "NullPos" is the number of formal parameters at the end which
447	// effectively count as part of the variadic arguments. This is
448	// useful if you would prefer to not have *any* formal parameters,
449	// but the language forces you to have at least one.
450	unsigned NullPos = Attr->getNullPos();
451	assert((NullPos == 0 || NullPos == 1) && "invalid null position on sentinel");
452	NumFormalParams = (NullPos > NumFormalParams ? 0 : NumFormalParams - NullPos);
453
454	// The number of arguments which should follow the sentinel.
455	unsigned NumArgsAfterSentinel = Attr->getSentinel();
456
457	// If there aren't enough arguments for all the formal parameters,
458	// the sentinel, and the args after the sentinel, complain.
459	if (Args.size() < NumFormalParams + NumArgsAfterSentinel + 1) {
460	Diag(Loc, DiagID: diag::warn_not_enough_argument) << D->getDeclName();
461	Diag(Loc: D->getLocation(), DiagID: diag::note_sentinel_here) << int(CalleeKind);
462	return;
463	}
464
465	// Otherwise, find the sentinel expression.
466	const Expr *SentinelExpr = Args[Args.size() - NumArgsAfterSentinel - 1];
467	if (!SentinelExpr)
468	return;
469	if (SentinelExpr->isValueDependent())
470	return;
471	if (Context.isSentinelNullExpr(E: SentinelExpr))
472	return;
473
474	// Pick a reasonable string to insert. Optimistically use 'nil', 'nullptr',
475	// or 'NULL' if those are actually defined in the context. Only use
476	// 'nil' for ObjC methods, where it's much more likely that the
477	// variadic arguments form a list of object pointers.
478	SourceLocation MissingNilLoc = getLocForEndOfToken(Loc: SentinelExpr->getEndLoc());
479	std::string NullValue;
480	if (CalleeKind == CK_Method && PP.isMacroDefined(Id: "nil"))
481	NullValue = "nil";
482	else if (getLangOpts().CPlusPlus11)
483	NullValue = "nullptr";
484	else if (PP.isMacroDefined(Id: "NULL"))
485	NullValue = "NULL";
486	else
487	NullValue = "(void*) 0";
488
489	if (MissingNilLoc.isInvalid())
490	Diag(Loc, DiagID: diag::warn_missing_sentinel) << int(CalleeKind);
491	else
492	Diag(Loc: MissingNilLoc, DiagID: diag::warn_missing_sentinel)
493	<< int(CalleeKind)
494	<< FixItHint::CreateInsertion(InsertionLoc: MissingNilLoc, Code: ", " + NullValue);
495	Diag(Loc: D->getLocation(), DiagID: diag::note_sentinel_here)
496	<< int(CalleeKind) << Attr->getRange();
497	}
498
499	SourceRange Sema::getExprRange(Expr *E) const {
500	return E ? E->getSourceRange() : SourceRange();
501	}
502
503	//===----------------------------------------------------------------------===//
504	// Standard Promotions and Conversions
505	//===----------------------------------------------------------------------===//
506
507	/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4).
508	ExprResult Sema::DefaultFunctionArrayConversion(Expr *E, bool Diagnose) {
509	// Handle any placeholder expressions which made it here.
510	if (E->hasPlaceholderType()) {
511	ExprResult result = CheckPlaceholderExpr(E);
512	if (result.isInvalid()) return ExprError();
513	E = result.get();
514	}
515
516	QualType Ty = E->getType();
517	assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type");
518
519	if (Ty->isFunctionType()) {
520	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: E->IgnoreParenCasts()))
521	if (auto *FD = dyn_cast<FunctionDecl>(Val: DRE->getDecl()))
522	if (!checkAddressOfFunctionIsAvailable(Function: FD, Complain: Diagnose, Loc: E->getExprLoc()))
523	return ExprError();
524
525	E = ImpCastExprToType(E, Type: Context.getPointerType(T: Ty),
526	CK: CK_FunctionToPointerDecay).get();
527	} else if (Ty->isArrayType()) {
528	// In C90 mode, arrays only promote to pointers if the array expression is
529	// an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has
530	// type 'array of type' is converted to an expression that has type 'pointer
531	// to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression
532	// that has type 'array of type' ...". The relevant change is "an lvalue"
533	// (C90) to "an expression" (C99).
534	//
535	// C++ 4.2p1:
536	// An lvalue or rvalue of type "array of N T" or "array of unknown bound of
537	// T" can be converted to an rvalue of type "pointer to T".
538	//
539	if (getLangOpts().C99 || getLangOpts().CPlusPlus || E->isLValue()) {
540	ExprResult Res = ImpCastExprToType(E, Type: Context.getArrayDecayedType(T: Ty),
541	CK: CK_ArrayToPointerDecay);
542	if (Res.isInvalid())
543	return ExprError();
544	E = Res.get();
545	}
546	}
547	return E;
548	}
549
550	static void CheckForNullPointerDereference(Sema &S, Expr *E) {
551	// Check to see if we are dereferencing a null pointer. If so,
552	// and if not volatile-qualified, this is undefined behavior that the
553	// optimizer will delete, so warn about it. People sometimes try to use this
554	// to get a deterministic trap and are surprised by clang's behavior. This
555	// only handles the pattern "*null", which is a very syntactic check.
556	const auto *UO = dyn_cast<UnaryOperator>(Val: E->IgnoreParenCasts());
557	if (UO && UO->getOpcode() == UO_Deref &&
558	UO->getSubExpr()->getType()->isPointerType()) {
559	const LangAS AS =
560	UO->getSubExpr()->getType()->getPointeeType().getAddressSpace();
561	if ((!isTargetAddressSpace(AS) ||
562	(isTargetAddressSpace(AS) && toTargetAddressSpace(AS) == 0)) &&
563	UO->getSubExpr()->IgnoreParenCasts()->isNullPointerConstant(
564	Ctx&: S.Context, NPC: Expr::NPC_ValueDependentIsNotNull) &&
565	!UO->getType().isVolatileQualified()) {
566	S.DiagRuntimeBehavior(Loc: UO->getOperatorLoc(), Statement: UO,
567	PD: S.PDiag(DiagID: diag::warn_indirection_through_null)
568	<< UO->getSubExpr()->getSourceRange());
569	S.DiagRuntimeBehavior(Loc: UO->getOperatorLoc(), Statement: UO,
570	PD: S.PDiag(DiagID: diag::note_indirection_through_null));
571	}
572	}
573	}
574
575	static void DiagnoseDirectIsaAccess(Sema &S, const ObjCIvarRefExpr *OIRE,
576	SourceLocation AssignLoc,
577	const Expr* RHS) {
578	const ObjCIvarDecl *IV = OIRE->getDecl();
579	if (!IV)
580	return;
581
582	DeclarationName MemberName = IV->getDeclName();
583	IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
584	if (!Member || !Member->isStr(Str: "isa"))
585	return;
586
587	const Expr *Base = OIRE->getBase();
588	QualType BaseType = Base->getType();
589	if (OIRE->isArrow())
590	BaseType = BaseType->getPointeeType();
591	if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>())
592	if (ObjCInterfaceDecl *IDecl = OTy->getInterface()) {
593	ObjCInterfaceDecl *ClassDeclared = nullptr;
594	ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(IVarName: Member, ClassDeclared);
595	if (!ClassDeclared->getSuperClass()
596	&& (*ClassDeclared->ivar_begin()) == IV) {
597	if (RHS) {
598	NamedDecl *ObjectSetClass =
599	S.LookupSingleName(S: S.TUScope,
600	Name: &S.Context.Idents.get(Name: "object_setClass"),
601	Loc: SourceLocation(), NameKind: S.LookupOrdinaryName);
602	if (ObjectSetClass) {
603	SourceLocation RHSLocEnd = S.getLocForEndOfToken(Loc: RHS->getEndLoc());
604	S.Diag(Loc: OIRE->getExprLoc(), DiagID: diag::warn_objc_isa_assign)
605	<< FixItHint::CreateInsertion(InsertionLoc: OIRE->getBeginLoc(),
606	Code: "object_setClass(")
607	<< FixItHint::CreateReplacement(
608	RemoveRange: SourceRange(OIRE->getOpLoc(), AssignLoc), Code: ",")
609	<< FixItHint::CreateInsertion(InsertionLoc: RHSLocEnd, Code: ")");
610	}
611	else
612	S.Diag(Loc: OIRE->getLocation(), DiagID: diag::warn_objc_isa_assign);
613	} else {
614	NamedDecl *ObjectGetClass =
615	S.LookupSingleName(S: S.TUScope,
616	Name: &S.Context.Idents.get(Name: "object_getClass"),
617	Loc: SourceLocation(), NameKind: S.LookupOrdinaryName);
618	if (ObjectGetClass)
619	S.Diag(Loc: OIRE->getExprLoc(), DiagID: diag::warn_objc_isa_use)
620	<< FixItHint::CreateInsertion(InsertionLoc: OIRE->getBeginLoc(),
621	Code: "object_getClass(")
622	<< FixItHint::CreateReplacement(
623	RemoveRange: SourceRange(OIRE->getOpLoc(), OIRE->getEndLoc()), Code: ")");
624	else
625	S.Diag(Loc: OIRE->getLocation(), DiagID: diag::warn_objc_isa_use);
626	}
627	S.Diag(Loc: IV->getLocation(), DiagID: diag::note_ivar_decl);
628	}
629	}
630	}
631
632	ExprResult Sema::DefaultLvalueConversion(Expr *E) {
633	// Handle any placeholder expressions which made it here.
634	if (E->hasPlaceholderType()) {
635	ExprResult result = CheckPlaceholderExpr(E);
636	if (result.isInvalid()) return ExprError();
637	E = result.get();
638	}
639
640	// C++ [conv.lval]p1:
641	// A glvalue of a non-function, non-array type T can be
642	// converted to a prvalue.
643	if (!E->isGLValue()) return E;
644
645	QualType T = E->getType();
646	assert(!T.isNull() && "r-value conversion on typeless expression?");
647
648	// lvalue-to-rvalue conversion cannot be applied to types that decay to
649	// pointers (i.e. function or array types).
650	if (T->canDecayToPointerType())
651	return E;
652
653	// We don't want to throw lvalue-to-rvalue casts on top of
654	// expressions of certain types in C++.
655	if (getLangOpts().CPlusPlus) {
656	if (T == Context.OverloadTy || T->isRecordType() ||
657	(T->isDependentType() && !T->isAnyPointerType() &&
658	!T->isMemberPointerType()))
659	return E;
660	}
661
662	// The C standard is actually really unclear on this point, and
663	// DR106 tells us what the result should be but not why. It's
664	// generally best to say that void types just doesn't undergo
665	// lvalue-to-rvalue at all. Note that expressions of unqualified
666	// 'void' type are never l-values, but qualified void can be.
667	if (T->isVoidType())
668	return E;
669
670	// OpenCL usually rejects direct accesses to values of 'half' type.
671	if (getLangOpts().OpenCL &&
672	!getOpenCLOptions().isAvailableOption(Ext: "cl_khr_fp16", LO: getLangOpts()) &&
673	T->isHalfType()) {
674	Diag(Loc: E->getExprLoc(), DiagID: diag::err_opencl_half_load_store)
675	<< 0 << T;
676	return ExprError();
677	}
678
679	CheckForNullPointerDereference(S&: *this, E);
680	if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(Val: E->IgnoreParenCasts())) {
681	NamedDecl *ObjectGetClass = LookupSingleName(S: TUScope,
682	Name: &Context.Idents.get(Name: "object_getClass"),
683	Loc: SourceLocation(), NameKind: LookupOrdinaryName);
684	if (ObjectGetClass)
685	Diag(Loc: E->getExprLoc(), DiagID: diag::warn_objc_isa_use)
686	<< FixItHint::CreateInsertion(InsertionLoc: OISA->getBeginLoc(), Code: "object_getClass(")
687	<< FixItHint::CreateReplacement(
688	RemoveRange: SourceRange(OISA->getOpLoc(), OISA->getIsaMemberLoc()), Code: ")");
689	else
690	Diag(Loc: E->getExprLoc(), DiagID: diag::warn_objc_isa_use);
691	}
692	else if (const ObjCIvarRefExpr *OIRE =
693	dyn_cast<ObjCIvarRefExpr>(Val: E->IgnoreParenCasts()))
694	DiagnoseDirectIsaAccess(S&: *this, OIRE, AssignLoc: SourceLocation(), /* Expr*/RHS: nullptr);
695
696	// C++ [conv.lval]p1:
697	// [...] If T is a non-class type, the type of the prvalue is the
698	// cv-unqualified version of T. Otherwise, the type of the
699	// rvalue is T.
700	//
701	// C99 6.3.2.1p2:
702	// If the lvalue has qualified type, the value has the unqualified
703	// version of the type of the lvalue; otherwise, the value has the
704	// type of the lvalue.
705	if (T.hasQualifiers())
706	T = T.getUnqualifiedType();
707
708	// Under the MS ABI, lock down the inheritance model now.
709	if (T->isMemberPointerType() &&
710	Context.getTargetInfo().getCXXABI().isMicrosoft())
711	(void)isCompleteType(Loc: E->getExprLoc(), T);
712
713	ExprResult Res = CheckLValueToRValueConversionOperand(E);
714	if (Res.isInvalid())
715	return Res;
716	E = Res.get();
717
718	// Loading a __weak object implicitly retains the value, so we need a cleanup to
719	// balance that.
720	if (E->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
721	Cleanup.setExprNeedsCleanups(true);
722
723	if (E->getType().isDestructedType() == QualType::DK_nontrivial_c_struct)
724	Cleanup.setExprNeedsCleanups(true);
725
726	if (!BoundsSafetyCheckUseOfCountAttrPtr(E: Res.get()))
727	return ExprError();
728
729	// C++ [conv.lval]p3:
730	// If T is cv std::nullptr_t, the result is a null pointer constant.
731	CastKind CK = T->isNullPtrType() ? CK_NullToPointer : CK_LValueToRValue;
732	Res = ImplicitCastExpr::Create(Context, T, Kind: CK, Operand: E, BasePath: nullptr, Cat: VK_PRValue,
733	FPO: CurFPFeatureOverrides());
734
735	// C11 6.3.2.1p2:
736	// ... if the lvalue has atomic type, the value has the non-atomic version
737	// of the type of the lvalue ...
738	if (const AtomicType *Atomic = T->getAs<AtomicType>()) {
739	T = Atomic->getValueType().getUnqualifiedType();
740	Res = ImplicitCastExpr::Create(Context, T, Kind: CK_AtomicToNonAtomic, Operand: Res.get(),
741	BasePath: nullptr, Cat: VK_PRValue, FPO: FPOptionsOverride());
742	}
743
744	return Res;
745	}
746
747	ExprResult Sema::DefaultFunctionArrayLvalueConversion(Expr *E, bool Diagnose) {
748	ExprResult Res = DefaultFunctionArrayConversion(E, Diagnose);
749	if (Res.isInvalid())
750	return ExprError();
751	Res = DefaultLvalueConversion(E: Res.get());
752	if (Res.isInvalid())
753	return ExprError();
754	return Res;
755	}
756
757	ExprResult Sema::CallExprUnaryConversions(Expr *E) {
758	QualType Ty = E->getType();
759	ExprResult Res = E;
760	// Only do implicit cast for a function type, but not for a pointer
761	// to function type.
762	if (Ty->isFunctionType()) {
763	Res = ImpCastExprToType(E, Type: Context.getPointerType(T: Ty),
764	CK: CK_FunctionToPointerDecay);
765	if (Res.isInvalid())
766	return ExprError();
767	}
768	Res = DefaultLvalueConversion(E: Res.get());
769	if (Res.isInvalid())
770	return ExprError();
771	return Res.get();
772	}
773
774	/// UsualUnaryFPConversions - Promotes floating-point types according to the
775	/// current language semantics.
776	ExprResult Sema::UsualUnaryFPConversions(Expr *E) {
777	QualType Ty = E->getType();
778	assert(!Ty.isNull() && "UsualUnaryFPConversions - missing type");
779
780	LangOptions::FPEvalMethodKind EvalMethod = CurFPFeatures.getFPEvalMethod();
781	if (EvalMethod != LangOptions::FEM_Source && Ty->isFloatingType() &&
782	(getLangOpts().getFPEvalMethod() !=
783	LangOptions::FPEvalMethodKind::FEM_UnsetOnCommandLine ||
784	PP.getLastFPEvalPragmaLocation().isValid())) {
785	switch (EvalMethod) {
786	default:
787	llvm_unreachable("Unrecognized float evaluation method");
788	break;
789	case LangOptions::FEM_UnsetOnCommandLine:
790	llvm_unreachable("Float evaluation method should be set by now");
791	break;
792	case LangOptions::FEM_Double:
793	if (Context.getFloatingTypeOrder(LHS: Context.DoubleTy, RHS: Ty) > 0)
794	// Widen the expression to double.
795	return Ty->isComplexType()
796	? ImpCastExprToType(E,
797	Type: Context.getComplexType(T: Context.DoubleTy),
798	CK: CK_FloatingComplexCast)
799	: ImpCastExprToType(E, Type: Context.DoubleTy, CK: CK_FloatingCast);
800	break;
801	case LangOptions::FEM_Extended:
802	if (Context.getFloatingTypeOrder(LHS: Context.LongDoubleTy, RHS: Ty) > 0)
803	// Widen the expression to long double.
804	return Ty->isComplexType()
805	? ImpCastExprToType(
806	E, Type: Context.getComplexType(T: Context.LongDoubleTy),
807	CK: CK_FloatingComplexCast)
808	: ImpCastExprToType(E, Type: Context.LongDoubleTy,
809	CK: CK_FloatingCast);
810	break;
811	}
812	}
813
814	// Half FP have to be promoted to float unless it is natively supported
815	if (Ty->isHalfType() && !getLangOpts().NativeHalfType)
816	return ImpCastExprToType(E, Type: Context.FloatTy, CK: CK_FloatingCast);
817
818	return E;
819	}
820
821	/// UsualUnaryConversions - Performs various conversions that are common to most
822	/// operators (C99 6.3). The conversions of array and function types are
823	/// sometimes suppressed. For example, the array->pointer conversion doesn't
824	/// apply if the array is an argument to the sizeof or address (&) operators.
825	/// In these instances, this routine should *not* be called.
826	ExprResult Sema::UsualUnaryConversions(Expr *E) {
827	// First, convert to an r-value.
828	ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
829	if (Res.isInvalid())
830	return ExprError();
831
832	// Promote floating-point types.
833	Res = UsualUnaryFPConversions(E: Res.get());
834	if (Res.isInvalid())
835	return ExprError();
836	E = Res.get();
837
838	QualType Ty = E->getType();
839	assert(!Ty.isNull() && "UsualUnaryConversions - missing type");
840
841	// Try to perform integral promotions if the object has a theoretically
842	// promotable type.
843	if (Ty->isIntegralOrUnscopedEnumerationType()) {
844	// C99 6.3.1.1p2:
845	//
846	// The following may be used in an expression wherever an int or
847	// unsigned int may be used:
848	// - an object or expression with an integer type whose integer
849	// conversion rank is less than or equal to the rank of int
850	// and unsigned int.
851	// - A bit-field of type _Bool, int, signed int, or unsigned int.
852	//
853	// If an int can represent all values of the original type, the
854	// value is converted to an int; otherwise, it is converted to an
855	// unsigned int. These are called the integer promotions. All
856	// other types are unchanged by the integer promotions.
857
858	QualType PTy = Context.isPromotableBitField(E);
859	if (!PTy.isNull()) {
860	E = ImpCastExprToType(E, Type: PTy, CK: CK_IntegralCast).get();
861	return E;
862	}
863	if (Context.isPromotableIntegerType(T: Ty)) {
864	QualType PT = Context.getPromotedIntegerType(PromotableType: Ty);
865	E = ImpCastExprToType(E, Type: PT, CK: CK_IntegralCast).get();
866	return E;
867	}
868	}
869	return E;
870	}
871
872	/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that
873	/// do not have a prototype. Arguments that have type float or __fp16
874	/// are promoted to double. All other argument types are converted by
875	/// UsualUnaryConversions().
876	ExprResult Sema::DefaultArgumentPromotion(Expr *E) {
877	QualType Ty = E->getType();
878	assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type");
879
880	ExprResult Res = UsualUnaryConversions(E);
881	if (Res.isInvalid())
882	return ExprError();
883	E = Res.get();
884
885	// If this is a 'float' or '__fp16' (CVR qualified or typedef)
886	// promote to double.
887	// Note that default argument promotion applies only to float (and
888	// half/fp16); it does not apply to _Float16.
889	const BuiltinType *BTy = Ty->getAs<BuiltinType>();
890	if (BTy && (BTy->getKind() == BuiltinType::Half ||
891	BTy->getKind() == BuiltinType::Float)) {
892	if (getLangOpts().OpenCL &&
893	!getOpenCLOptions().isAvailableOption(Ext: "cl_khr_fp64", LO: getLangOpts())) {
894	if (BTy->getKind() == BuiltinType::Half) {
895	E = ImpCastExprToType(E, Type: Context.FloatTy, CK: CK_FloatingCast).get();
896	}
897	} else {
898	E = ImpCastExprToType(E, Type: Context.DoubleTy, CK: CK_FloatingCast).get();
899	}
900	}
901	if (BTy &&
902	getLangOpts().getExtendIntArgs() ==
903	LangOptions::ExtendArgsKind::ExtendTo64 &&
904	Context.getTargetInfo().supportsExtendIntArgs() && Ty->isIntegerType() &&
905	Context.getTypeSizeInChars(T: BTy) <
906	Context.getTypeSizeInChars(T: Context.LongLongTy)) {
907	E = (Ty->isUnsignedIntegerType())
908	? ImpCastExprToType(E, Type: Context.UnsignedLongLongTy, CK: CK_IntegralCast)
909	.get()
910	: ImpCastExprToType(E, Type: Context.LongLongTy, CK: CK_IntegralCast).get();
911	assert(8 == Context.getTypeSizeInChars(Context.LongLongTy).getQuantity() &&
912	"Unexpected typesize for LongLongTy");
913	}
914
915	// C++ performs lvalue-to-rvalue conversion as a default argument
916	// promotion, even on class types, but note:
917	// C++11 [conv.lval]p2:
918	// When an lvalue-to-rvalue conversion occurs in an unevaluated
919	// operand or a subexpression thereof the value contained in the
920	// referenced object is not accessed. Otherwise, if the glvalue
921	// has a class type, the conversion copy-initializes a temporary
922	// of type T from the glvalue and the result of the conversion
923	// is a prvalue for the temporary.
924	// FIXME: add some way to gate this entire thing for correctness in
925	// potentially potentially evaluated contexts.
926	if (getLangOpts().CPlusPlus && E->isGLValue() && !isUnevaluatedContext()) {
927	ExprResult Temp = PerformCopyInitialization(
928	Entity: InitializedEntity::InitializeTemporary(Type: E->getType()),
929	EqualLoc: E->getExprLoc(), Init: E);
930	if (Temp.isInvalid())
931	return ExprError();
932	E = Temp.get();
933	}
934
935	// C++ [expr.call]p7, per CWG722:
936	// An argument that has (possibly cv-qualified) type std::nullptr_t is
937	// converted to void* ([conv.ptr]).
938	// (This does not apply to C23 nullptr)
939	if (getLangOpts().CPlusPlus && E->getType()->isNullPtrType())
940	E = ImpCastExprToType(E, Type: Context.VoidPtrTy, CK: CK_NullToPointer).get();
941
942	return E;
943	}
944
945	VarArgKind Sema::isValidVarArgType(const QualType &Ty) {
946	if (Ty->isIncompleteType()) {
947	// C++11 [expr.call]p7:
948	// After these conversions, if the argument does not have arithmetic,
949	// enumeration, pointer, pointer to member, or class type, the program
950	// is ill-formed.
951	//
952	// Since we've already performed null pointer conversion, array-to-pointer
953	// decay and function-to-pointer decay, the only such type in C++ is cv
954	// void. This also handles initializer lists as variadic arguments.
955	if (Ty->isVoidType())
956	return VarArgKind::Invalid;
957
958	if (Ty->isObjCObjectType())
959	return VarArgKind::Invalid;
960	return VarArgKind::Valid;
961	}
962
963	if (Ty.isDestructedType() == QualType::DK_nontrivial_c_struct)
964	return VarArgKind::Invalid;
965
966	if (Context.getTargetInfo().getTriple().isWasm() &&
967	Ty.isWebAssemblyReferenceType()) {
968	return VarArgKind::Invalid;
969	}
970
971	if (Ty.isCXX98PODType(Context))
972	return VarArgKind::Valid;
973
974	// C++11 [expr.call]p7:
975	// Passing a potentially-evaluated argument of class type (Clause 9)
976	// having a non-trivial copy constructor, a non-trivial move constructor,
977	// or a non-trivial destructor, with no corresponding parameter,
978	// is conditionally-supported with implementation-defined semantics.
979	if (getLangOpts().CPlusPlus11 && !Ty->isDependentType())
980	if (CXXRecordDecl *Record = Ty->getAsCXXRecordDecl())
981	if (!Record->hasNonTrivialCopyConstructor() &&
982	!Record->hasNonTrivialMoveConstructor() &&
983	!Record->hasNonTrivialDestructor())
984	return VarArgKind::ValidInCXX11;
985
986	if (getLangOpts().ObjCAutoRefCount && Ty->isObjCLifetimeType())
987	return VarArgKind::Valid;
988
989	if (Ty->isObjCObjectType())
990	return VarArgKind::Invalid;
991
992	if (getLangOpts().HLSL && Ty->getAs<HLSLAttributedResourceType>())
993	return VarArgKind::Valid;
994
995	if (getLangOpts().MSVCCompat)
996	return VarArgKind::MSVCUndefined;
997
998	if (getLangOpts().HLSL && Ty->getAs<HLSLAttributedResourceType>())
999	return VarArgKind::Valid;
1000
1001	// FIXME: In C++11, these cases are conditionally-supported, meaning we're
1002	// permitted to reject them. We should consider doing so.
1003	return VarArgKind::Undefined;
1004	}
1005
1006	void Sema::checkVariadicArgument(const Expr *E, VariadicCallType CT) {
1007	// Don't allow one to pass an Objective-C interface to a vararg.
1008	const QualType &Ty = E->getType();
1009	VarArgKind VAK = isValidVarArgType(Ty);
1010
1011	// Complain about passing non-POD types through varargs.
1012	switch (VAK) {
1013	case VarArgKind::ValidInCXX11:
1014	DiagRuntimeBehavior(
1015	Loc: E->getBeginLoc(), Statement: nullptr,
1016	PD: PDiag(DiagID: diag::warn_cxx98_compat_pass_non_pod_arg_to_vararg) << Ty << CT);
1017	[[fallthrough]];
1018	case VarArgKind::Valid:
1019	if (Ty->isRecordType()) {
1020	// This is unlikely to be what the user intended. If the class has a
1021	// 'c_str' member function, the user probably meant to call that.
1022	DiagRuntimeBehavior(Loc: E->getBeginLoc(), Statement: nullptr,
1023	PD: PDiag(DiagID: diag::warn_pass_class_arg_to_vararg)
1024	<< Ty << CT << hasCStrMethod(E) << ".c_str()");
1025	}
1026	break;
1027
1028	case VarArgKind::Undefined:
1029	case VarArgKind::MSVCUndefined:
1030	DiagRuntimeBehavior(Loc: E->getBeginLoc(), Statement: nullptr,
1031	PD: PDiag(DiagID: diag::warn_cannot_pass_non_pod_arg_to_vararg)
1032	<< getLangOpts().CPlusPlus11 << Ty << CT);
1033	break;
1034
1035	case VarArgKind::Invalid:
1036	if (Ty.isDestructedType() == QualType::DK_nontrivial_c_struct)
1037	Diag(Loc: E->getBeginLoc(),
1038	DiagID: diag::err_cannot_pass_non_trivial_c_struct_to_vararg)
1039	<< Ty << CT;
1040	else if (Ty->isObjCObjectType())
1041	DiagRuntimeBehavior(Loc: E->getBeginLoc(), Statement: nullptr,
1042	PD: PDiag(DiagID: diag::err_cannot_pass_objc_interface_to_vararg)
1043	<< Ty << CT);
1044	else
1045	Diag(Loc: E->getBeginLoc(), DiagID: diag::err_cannot_pass_to_vararg)
1046	<< isa<InitListExpr>(Val: E) << Ty << CT;
1047	break;
1048	}
1049	}
1050
1051	ExprResult Sema::DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT,
1052	FunctionDecl *FDecl) {
1053	if (const BuiltinType *PlaceholderTy = E->getType()->getAsPlaceholderType()) {
1054	// Strip the unbridged-cast placeholder expression off, if applicable.
1055	if (PlaceholderTy->getKind() == BuiltinType::ARCUnbridgedCast &&
1056	(CT == VariadicCallType::Method ||
1057	(FDecl && FDecl->hasAttr<CFAuditedTransferAttr>()))) {
1058	E = ObjC().stripARCUnbridgedCast(e: E);
1059
1060	// Otherwise, do normal placeholder checking.
1061	} else {
1062	ExprResult ExprRes = CheckPlaceholderExpr(E);
1063	if (ExprRes.isInvalid())
1064	return ExprError();
1065	E = ExprRes.get();
1066	}
1067	}
1068
1069	ExprResult ExprRes = DefaultArgumentPromotion(E);
1070	if (ExprRes.isInvalid())
1071	return ExprError();
1072
1073	// Copy blocks to the heap.
1074	if (ExprRes.get()->getType()->isBlockPointerType())
1075	maybeExtendBlockObject(E&: ExprRes);
1076
1077	E = ExprRes.get();
1078
1079	// Diagnostics regarding non-POD argument types are
1080	// emitted along with format string checking in Sema::CheckFunctionCall().
1081	if (isValidVarArgType(Ty: E->getType()) == VarArgKind::Undefined) {
1082	// Turn this into a trap.
1083	CXXScopeSpec SS;
1084	SourceLocation TemplateKWLoc;
1085	UnqualifiedId Name;
1086	Name.setIdentifier(Id: PP.getIdentifierInfo(Name: "__builtin_trap"),
1087	IdLoc: E->getBeginLoc());
1088	ExprResult TrapFn = ActOnIdExpression(S: TUScope, SS, TemplateKWLoc, Id&: Name,
1089	/*HasTrailingLParen=*/true,
1090	/*IsAddressOfOperand=*/false);
1091	if (TrapFn.isInvalid())
1092	return ExprError();
1093
1094	ExprResult Call = BuildCallExpr(S: TUScope, Fn: TrapFn.get(), LParenLoc: E->getBeginLoc(), ArgExprs: {},
1095	RParenLoc: E->getEndLoc());
1096	if (Call.isInvalid())
1097	return ExprError();
1098
1099	ExprResult Comma =
1100	ActOnBinOp(S: TUScope, TokLoc: E->getBeginLoc(), Kind: tok::comma, LHSExpr: Call.get(), RHSExpr: E);
1101	if (Comma.isInvalid())
1102	return ExprError();
1103	return Comma.get();
1104	}
1105
1106	if (!getLangOpts().CPlusPlus &&
1107	RequireCompleteType(Loc: E->getExprLoc(), T: E->getType(),
1108	DiagID: diag::err_call_incomplete_argument))
1109	return ExprError();
1110
1111	return E;
1112	}
1113
1114	/// Convert complex integers to complex floats and real integers to
1115	/// real floats as required for complex arithmetic. Helper function of
1116	/// UsualArithmeticConversions()
1117	///
1118	/// \return false if the integer expression is an integer type and is
1119	/// successfully converted to the (complex) float type.
1120	static bool handleComplexIntegerToFloatConversion(Sema &S, ExprResult &IntExpr,
1121	ExprResult &ComplexExpr,
1122	QualType IntTy,
1123	QualType ComplexTy,
1124	bool SkipCast) {
1125	if (IntTy->isComplexType() || IntTy->isRealFloatingType()) return true;
1126	if (SkipCast) return false;
1127	if (IntTy->isIntegerType()) {
1128	QualType fpTy = ComplexTy->castAs<ComplexType>()->getElementType();
1129	IntExpr = S.ImpCastExprToType(E: IntExpr.get(), Type: fpTy, CK: CK_IntegralToFloating);
1130	} else {
1131	assert(IntTy->isComplexIntegerType());
1132	IntExpr = S.ImpCastExprToType(E: IntExpr.get(), Type: ComplexTy,
1133	CK: CK_IntegralComplexToFloatingComplex);
1134	}
1135	return false;
1136	}
1137
1138	// This handles complex/complex, complex/float, or float/complex.
1139	// When both operands are complex, the shorter operand is converted to the
1140	// type of the longer, and that is the type of the result. This corresponds
1141	// to what is done when combining two real floating-point operands.
1142	// The fun begins when size promotion occur across type domains.
1143	// From H&S 6.3.4: When one operand is complex and the other is a real
1144	// floating-point type, the less precise type is converted, within it's
1145	// real or complex domain, to the precision of the other type. For example,
1146	// when combining a "long double" with a "double _Complex", the
1147	// "double _Complex" is promoted to "long double _Complex".
1148	static QualType handleComplexFloatConversion(Sema &S, ExprResult &Shorter,
1149	QualType ShorterType,
1150	QualType LongerType,
1151	bool PromotePrecision) {
1152	bool LongerIsComplex = isa<ComplexType>(Val: LongerType.getCanonicalType());
1153	QualType Result =
1154	LongerIsComplex ? LongerType : S.Context.getComplexType(T: LongerType);
1155
1156	if (PromotePrecision) {
1157	if (isa<ComplexType>(Val: ShorterType.getCanonicalType())) {
1158	Shorter =
1159	S.ImpCastExprToType(E: Shorter.get(), Type: Result, CK: CK_FloatingComplexCast);
1160	} else {
1161	if (LongerIsComplex)
1162	LongerType = LongerType->castAs<ComplexType>()->getElementType();
1163	Shorter = S.ImpCastExprToType(E: Shorter.get(), Type: LongerType, CK: CK_FloatingCast);
1164	}
1165	}
1166	return Result;
1167	}
1168
1169	/// Handle arithmetic conversion with complex types. Helper function of
1170	/// UsualArithmeticConversions()
1171	static QualType handleComplexConversion(Sema &S, ExprResult &LHS,
1172	ExprResult &RHS, QualType LHSType,
1173	QualType RHSType, bool IsCompAssign) {
1174	// Handle (complex) integer types.
1175	if (!handleComplexIntegerToFloatConversion(S, IntExpr&: RHS, ComplexExpr&: LHS, IntTy: RHSType, ComplexTy: LHSType,
1176	/*SkipCast=*/false))
1177	return LHSType;
1178	if (!handleComplexIntegerToFloatConversion(S, IntExpr&: LHS, ComplexExpr&: RHS, IntTy: LHSType, ComplexTy: RHSType,
1179	/*SkipCast=*/IsCompAssign))
1180	return RHSType;
1181
1182	// Compute the rank of the two types, regardless of whether they are complex.
1183	int Order = S.Context.getFloatingTypeOrder(LHS: LHSType, RHS: RHSType);
1184	if (Order < 0)
1185	// Promote the precision of the LHS if not an assignment.
1186	return handleComplexFloatConversion(S, Shorter&: LHS, ShorterType: LHSType, LongerType: RHSType,
1187	/*PromotePrecision=*/!IsCompAssign);
1188	// Promote the precision of the RHS unless it is already the same as the LHS.
1189	return handleComplexFloatConversion(S, Shorter&: RHS, ShorterType: RHSType, LongerType: LHSType,
1190	/*PromotePrecision=*/Order > 0);
1191	}
1192
1193	/// Handle arithmetic conversion from integer to float. Helper function
1194	/// of UsualArithmeticConversions()
1195	static QualType handleIntToFloatConversion(Sema &S, ExprResult &FloatExpr,
1196	ExprResult &IntExpr,
1197	QualType FloatTy, QualType IntTy,
1198	bool ConvertFloat, bool ConvertInt) {
1199	if (IntTy->isIntegerType()) {
1200	if (ConvertInt)
1201	// Convert intExpr to the lhs floating point type.
1202	IntExpr = S.ImpCastExprToType(E: IntExpr.get(), Type: FloatTy,
1203	CK: CK_IntegralToFloating);
1204	return FloatTy;
1205	}
1206
1207	// Convert both sides to the appropriate complex float.
1208	assert(IntTy->isComplexIntegerType());
1209	QualType result = S.Context.getComplexType(T: FloatTy);
1210
1211	// _Complex int -> _Complex float
1212	if (ConvertInt)
1213	IntExpr = S.ImpCastExprToType(E: IntExpr.get(), Type: result,
1214	CK: CK_IntegralComplexToFloatingComplex);
1215
1216	// float -> _Complex float
1217	if (ConvertFloat)
1218	FloatExpr = S.ImpCastExprToType(E: FloatExpr.get(), Type: result,
1219	CK: CK_FloatingRealToComplex);
1220
1221	return result;
1222	}
1223
1224	/// Handle arithmethic conversion with floating point types. Helper
1225	/// function of UsualArithmeticConversions()
1226	static QualType handleFloatConversion(Sema &S, ExprResult &LHS,
1227	ExprResult &RHS, QualType LHSType,
1228	QualType RHSType, bool IsCompAssign) {
1229	bool LHSFloat = LHSType->isRealFloatingType();
1230	bool RHSFloat = RHSType->isRealFloatingType();
1231
1232	// N1169 4.1.4: If one of the operands has a floating type and the other
1233	// operand has a fixed-point type, the fixed-point operand
1234	// is converted to the floating type [...]
1235	if (LHSType->isFixedPointType() || RHSType->isFixedPointType()) {
1236	if (LHSFloat)
1237	RHS = S.ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_FixedPointToFloating);
1238	else if (!IsCompAssign)
1239	LHS = S.ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_FixedPointToFloating);
1240	return LHSFloat ? LHSType : RHSType;
1241	}
1242
1243	// If we have two real floating types, convert the smaller operand
1244	// to the bigger result.
1245	if (LHSFloat && RHSFloat) {
1246	int order = S.Context.getFloatingTypeOrder(LHS: LHSType, RHS: RHSType);
1247	if (order > 0) {
1248	RHS = S.ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_FloatingCast);
1249	return LHSType;
1250	}
1251
1252	assert(order < 0 && "illegal float comparison");
1253	if (!IsCompAssign)
1254	LHS = S.ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_FloatingCast);
1255	return RHSType;
1256	}
1257
1258	if (LHSFloat) {
1259	// Half FP has to be promoted to float unless it is natively supported
1260	if (LHSType->isHalfType() && !S.getLangOpts().NativeHalfType)
1261	LHSType = S.Context.FloatTy;
1262
1263	return handleIntToFloatConversion(S, FloatExpr&: LHS, IntExpr&: RHS, FloatTy: LHSType, IntTy: RHSType,
1264	/*ConvertFloat=*/!IsCompAssign,
1265	/*ConvertInt=*/ true);
1266	}
1267	assert(RHSFloat);
1268	return handleIntToFloatConversion(S, FloatExpr&: RHS, IntExpr&: LHS, FloatTy: RHSType, IntTy: LHSType,
1269	/*ConvertFloat=*/ true,
1270	/*ConvertInt=*/!IsCompAssign);
1271	}
1272
1273	/// Diagnose attempts to convert between __float128, __ibm128 and
1274	/// long double if there is no support for such conversion.
1275	/// Helper function of UsualArithmeticConversions().
1276	static bool unsupportedTypeConversion(const Sema &S, QualType LHSType,
1277	QualType RHSType) {
1278	// No issue if either is not a floating point type.
1279	if (!LHSType->isFloatingType() || !RHSType->isFloatingType())
1280	return false;
1281
1282	// No issue if both have the same 128-bit float semantics.
1283	auto *LHSComplex = LHSType->getAs<ComplexType>();
1284	auto *RHSComplex = RHSType->getAs<ComplexType>();
1285
1286	QualType LHSElem = LHSComplex ? LHSComplex->getElementType() : LHSType;
1287	QualType RHSElem = RHSComplex ? RHSComplex->getElementType() : RHSType;
1288
1289	const llvm::fltSemantics &LHSSem = S.Context.getFloatTypeSemantics(T: LHSElem);
1290	const llvm::fltSemantics &RHSSem = S.Context.getFloatTypeSemantics(T: RHSElem);
1291
1292	if ((&LHSSem != &llvm::APFloat::PPCDoubleDouble() ||
1293	&RHSSem != &llvm::APFloat::IEEEquad()) &&
1294	(&LHSSem != &llvm::APFloat::IEEEquad() ||
1295	&RHSSem != &llvm::APFloat::PPCDoubleDouble()))
1296	return false;
1297
1298	return true;
1299	}
1300
1301	typedef ExprResult PerformCastFn(Sema &S, Expr *operand, QualType toType);
1302
1303	namespace {
1304	/// These helper callbacks are placed in an anonymous namespace to
1305	/// permit their use as function template parameters.
1306	ExprResult doIntegralCast(Sema &S, Expr *op, QualType toType) {
1307	return S.ImpCastExprToType(E: op, Type: toType, CK: CK_IntegralCast);
1308	}
1309
1310	ExprResult doComplexIntegralCast(Sema &S, Expr *op, QualType toType) {
1311	return S.ImpCastExprToType(E: op, Type: S.Context.getComplexType(T: toType),
1312	CK: CK_IntegralComplexCast);
1313	}
1314	}
1315
1316	/// Handle integer arithmetic conversions. Helper function of
1317	/// UsualArithmeticConversions()
1318	template <PerformCastFn doLHSCast, PerformCastFn doRHSCast>
1319	static QualType handleIntegerConversion(Sema &S, ExprResult &LHS,
1320	ExprResult &RHS, QualType LHSType,
1321	QualType RHSType, bool IsCompAssign) {
1322	// The rules for this case are in C99 6.3.1.8
1323	int order = S.Context.getIntegerTypeOrder(LHS: LHSType, RHS: RHSType);
1324	bool LHSSigned = LHSType->hasSignedIntegerRepresentation();
1325	bool RHSSigned = RHSType->hasSignedIntegerRepresentation();
1326	if (LHSSigned == RHSSigned) {
1327	// Same signedness; use the higher-ranked type
1328	if (order >= 0) {
1329	RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1330	return LHSType;
1331	} else if (!IsCompAssign)
1332	LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1333	return RHSType;
1334	} else if (order != (LHSSigned ? 1 : -1)) {
1335	// The unsigned type has greater than or equal rank to the
1336	// signed type, so use the unsigned type
1337	if (RHSSigned) {
1338	RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1339	return LHSType;
1340	} else if (!IsCompAssign)
1341	LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1342	return RHSType;
1343	} else if (S.Context.getIntWidth(T: LHSType) != S.Context.getIntWidth(T: RHSType)) {
1344	// The two types are different widths; if we are here, that
1345	// means the signed type is larger than the unsigned type, so
1346	// use the signed type.
1347	if (LHSSigned) {
1348	RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1349	return LHSType;
1350	} else if (!IsCompAssign)
1351	LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1352	return RHSType;
1353	} else {
1354	// The signed type is higher-ranked than the unsigned type,
1355	// but isn't actually any bigger (like unsigned int and long
1356	// on most 32-bit systems). Use the unsigned type corresponding
1357	// to the signed type.
1358	QualType result =
1359	S.Context.getCorrespondingUnsignedType(T: LHSSigned ? LHSType : RHSType);
1360	RHS = (*doRHSCast)(S, RHS.get(), result);
1361	if (!IsCompAssign)
1362	LHS = (*doLHSCast)(S, LHS.get(), result);
1363	return result;
1364	}
1365	}
1366
1367	/// Handle conversions with GCC complex int extension. Helper function
1368	/// of UsualArithmeticConversions()
1369	static QualType handleComplexIntConversion(Sema &S, ExprResult &LHS,
1370	ExprResult &RHS, QualType LHSType,
1371	QualType RHSType,
1372	bool IsCompAssign) {
1373	const ComplexType *LHSComplexInt = LHSType->getAsComplexIntegerType();
1374	const ComplexType *RHSComplexInt = RHSType->getAsComplexIntegerType();
1375
1376	if (LHSComplexInt && RHSComplexInt) {
1377	QualType LHSEltType = LHSComplexInt->getElementType();
1378	QualType RHSEltType = RHSComplexInt->getElementType();
1379	QualType ScalarType =
1380	handleIntegerConversion<doComplexIntegralCast, doComplexIntegralCast>
1381	(S, LHS, RHS, LHSType: LHSEltType, RHSType: RHSEltType, IsCompAssign);
1382
1383	return S.Context.getComplexType(T: ScalarType);
1384	}
1385
1386	if (LHSComplexInt) {
1387	QualType LHSEltType = LHSComplexInt->getElementType();
1388	QualType ScalarType =
1389	handleIntegerConversion<doComplexIntegralCast, doIntegralCast>
1390	(S, LHS, RHS, LHSType: LHSEltType, RHSType, IsCompAssign);
1391	QualType ComplexType = S.Context.getComplexType(T: ScalarType);
1392	RHS = S.ImpCastExprToType(E: RHS.get(), Type: ComplexType,
1393	CK: CK_IntegralRealToComplex);
1394
1395	return ComplexType;
1396	}
1397
1398	assert(RHSComplexInt);
1399
1400	QualType RHSEltType = RHSComplexInt->getElementType();
1401	QualType ScalarType =
1402	handleIntegerConversion<doIntegralCast, doComplexIntegralCast>
1403	(S, LHS, RHS, LHSType, RHSType: RHSEltType, IsCompAssign);
1404	QualType ComplexType = S.Context.getComplexType(T: ScalarType);
1405
1406	if (!IsCompAssign)
1407	LHS = S.ImpCastExprToType(E: LHS.get(), Type: ComplexType,
1408	CK: CK_IntegralRealToComplex);
1409	return ComplexType;
1410	}
1411
1412	/// Return the rank of a given fixed point or integer type. The value itself
1413	/// doesn't matter, but the values must be increasing with proper increasing
1414	/// rank as described in N1169 4.1.1.
1415	static unsigned GetFixedPointRank(QualType Ty) {
1416	const auto *BTy = Ty->getAs<BuiltinType>();
1417	assert(BTy && "Expected a builtin type.");
1418
1419	switch (BTy->getKind()) {
1420	case BuiltinType::ShortFract:
1421	case BuiltinType::UShortFract:
1422	case BuiltinType::SatShortFract:
1423	case BuiltinType::SatUShortFract:
1424	return 1;
1425	case BuiltinType::Fract:
1426	case BuiltinType::UFract:
1427	case BuiltinType::SatFract:
1428	case BuiltinType::SatUFract:
1429	return 2;
1430	case BuiltinType::LongFract:
1431	case BuiltinType::ULongFract:
1432	case BuiltinType::SatLongFract:
1433	case BuiltinType::SatULongFract:
1434	return 3;
1435	case BuiltinType::ShortAccum:
1436	case BuiltinType::UShortAccum:
1437	case BuiltinType::SatShortAccum:
1438	case BuiltinType::SatUShortAccum:
1439	return 4;
1440	case BuiltinType::Accum:
1441	case BuiltinType::UAccum:
1442	case BuiltinType::SatAccum:
1443	case BuiltinType::SatUAccum:
1444	return 5;
1445	case BuiltinType::LongAccum:
1446	case BuiltinType::ULongAccum:
1447	case BuiltinType::SatLongAccum:
1448	case BuiltinType::SatULongAccum:
1449	return 6;
1450	default:
1451	if (BTy->isInteger())
1452	return 0;
1453	llvm_unreachable("Unexpected fixed point or integer type");
1454	}
1455	}
1456
1457	/// handleFixedPointConversion - Fixed point operations between fixed
1458	/// point types and integers or other fixed point types do not fall under
1459	/// usual arithmetic conversion since these conversions could result in loss
1460	/// of precsision (N1169 4.1.4). These operations should be calculated with
1461	/// the full precision of their result type (N1169 4.1.6.2.1).
1462	static QualType handleFixedPointConversion(Sema &S, QualType LHSTy,
1463	QualType RHSTy) {
1464	assert((LHSTy->isFixedPointType() || RHSTy->isFixedPointType()) &&
1465	"Expected at least one of the operands to be a fixed point type");
1466	assert((LHSTy->isFixedPointOrIntegerType() ||
1467	RHSTy->isFixedPointOrIntegerType()) &&
1468	"Special fixed point arithmetic operation conversions are only "
1469	"applied to ints or other fixed point types");
1470
1471	// If one operand has signed fixed-point type and the other operand has
1472	// unsigned fixed-point type, then the unsigned fixed-point operand is
1473	// converted to its corresponding signed fixed-point type and the resulting
1474	// type is the type of the converted operand.
1475	if (RHSTy->isSignedFixedPointType() && LHSTy->isUnsignedFixedPointType())
1476	LHSTy = S.Context.getCorrespondingSignedFixedPointType(Ty: LHSTy);
1477	else if (RHSTy->isUnsignedFixedPointType() && LHSTy->isSignedFixedPointType())
1478	RHSTy = S.Context.getCorrespondingSignedFixedPointType(Ty: RHSTy);
1479
1480	// The result type is the type with the highest rank, whereby a fixed-point
1481	// conversion rank is always greater than an integer conversion rank; if the
1482	// type of either of the operands is a saturating fixedpoint type, the result
1483	// type shall be the saturating fixed-point type corresponding to the type
1484	// with the highest rank; the resulting value is converted (taking into
1485	// account rounding and overflow) to the precision of the resulting type.
1486	// Same ranks between signed and unsigned types are resolved earlier, so both
1487	// types are either signed or both unsigned at this point.
1488	unsigned LHSTyRank = GetFixedPointRank(Ty: LHSTy);
1489	unsigned RHSTyRank = GetFixedPointRank(Ty: RHSTy);
1490
1491	QualType ResultTy = LHSTyRank > RHSTyRank ? LHSTy : RHSTy;
1492
1493	if (LHSTy->isSaturatedFixedPointType() || RHSTy->isSaturatedFixedPointType())
1494	ResultTy = S.Context.getCorrespondingSaturatedType(Ty: ResultTy);
1495
1496	return ResultTy;
1497	}
1498
1499	/// Check that the usual arithmetic conversions can be performed on this pair of
1500	/// expressions that might be of enumeration type.
1501	void Sema::checkEnumArithmeticConversions(Expr *LHS, Expr *RHS,
1502	SourceLocation Loc,
1503	ArithConvKind ACK) {
1504	// C++2a [expr.arith.conv]p1:
1505	// If one operand is of enumeration type and the other operand is of a
1506	// different enumeration type or a floating-point type, this behavior is
1507	// deprecated ([depr.arith.conv.enum]).
1508	//
1509	// Warn on this in all language modes. Produce a deprecation warning in C++20.
1510	// Eventually we will presumably reject these cases (in C++23 onwards?).
1511	QualType L = LHS->getEnumCoercedType(Ctx: Context),
1512	R = RHS->getEnumCoercedType(Ctx: Context);
1513	bool LEnum = L->isUnscopedEnumerationType(),
1514	REnum = R->isUnscopedEnumerationType();
1515	bool IsCompAssign = ACK == ArithConvKind::CompAssign;
1516	if ((!IsCompAssign && LEnum && R->isFloatingType()) ||
1517	(REnum && L->isFloatingType())) {
1518	Diag(Loc, DiagID: getLangOpts().CPlusPlus26 ? diag::err_arith_conv_enum_float_cxx26
1519	: getLangOpts().CPlusPlus20
1520	? diag::warn_arith_conv_enum_float_cxx20
1521	: diag::warn_arith_conv_enum_float)
1522	<< LHS->getSourceRange() << RHS->getSourceRange() << (int)ACK << LEnum
1523	<< L << R;
1524	} else if (!IsCompAssign && LEnum && REnum &&
1525	!Context.hasSameUnqualifiedType(T1: L, T2: R)) {
1526	unsigned DiagID;
1527	// In C++ 26, usual arithmetic conversions between 2 different enum types
1528	// are ill-formed.
1529	if (getLangOpts().CPlusPlus26)
1530	DiagID = diag::warn_conv_mixed_enum_types_cxx26;
1531	else if (!L->castAs<EnumType>()->getDecl()->hasNameForLinkage() ||
1532	!R->castAs<EnumType>()->getDecl()->hasNameForLinkage()) {
1533	// If either enumeration type is unnamed, it's less likely that the
1534	// user cares about this, but this situation is still deprecated in
1535	// C++2a. Use a different warning group.
1536	DiagID = getLangOpts().CPlusPlus20
1537	? diag::warn_arith_conv_mixed_anon_enum_types_cxx20
1538	: diag::warn_arith_conv_mixed_anon_enum_types;
1539	} else if (ACK == ArithConvKind::Conditional) {
1540	// Conditional expressions are separated out because they have
1541	// historically had a different warning flag.
1542	DiagID = getLangOpts().CPlusPlus20
1543	? diag::warn_conditional_mixed_enum_types_cxx20
1544	: diag::warn_conditional_mixed_enum_types;
1545	} else if (ACK == ArithConvKind::Comparison) {
1546	// Comparison expressions are separated out because they have
1547	// historically had a different warning flag.
1548	DiagID = getLangOpts().CPlusPlus20
1549	? diag::warn_comparison_mixed_enum_types_cxx20
1550	: diag::warn_comparison_mixed_enum_types;
1551	} else {
1552	DiagID = getLangOpts().CPlusPlus20
1553	? diag::warn_arith_conv_mixed_enum_types_cxx20
1554	: diag::warn_arith_conv_mixed_enum_types;
1555	}
1556	Diag(Loc, DiagID) << LHS->getSourceRange() << RHS->getSourceRange()
1557	<< (int)ACK << L << R;
1558	}
1559	}
1560
1561	static void CheckUnicodeArithmeticConversions(Sema &SemaRef, Expr *LHS,
1562	Expr *RHS, SourceLocation Loc,
1563	ArithConvKind ACK) {
1564	QualType LHSType = LHS->getType().getUnqualifiedType();
1565	QualType RHSType = RHS->getType().getUnqualifiedType();
1566
1567	if (!SemaRef.getLangOpts().CPlusPlus || !LHSType->isUnicodeCharacterType() ||
1568	!RHSType->isUnicodeCharacterType())
1569	return;
1570
1571	if (ACK == ArithConvKind::Comparison) {
1572	if (SemaRef.getASTContext().hasSameType(T1: LHSType, T2: RHSType))
1573	return;
1574
1575	auto IsSingleCodeUnitCP = [](const QualType &T, const llvm::APSInt &Value) {
1576	if (T->isChar8Type())
1577	return llvm::IsSingleCodeUnitUTF8Codepoint(Value.getExtValue());
1578	if (T->isChar16Type())
1579	return llvm::IsSingleCodeUnitUTF16Codepoint(Value.getExtValue());
1580	assert(T->isChar32Type());
1581	return llvm::IsSingleCodeUnitUTF32Codepoint(Value.getExtValue());
1582	};
1583
1584	Expr::EvalResult LHSRes, RHSRes;
1585	bool LHSSuccess = LHS->EvaluateAsInt(Result&: LHSRes, Ctx: SemaRef.getASTContext(),
1586	AllowSideEffects: Expr::SE_AllowSideEffects,
1587	InConstantContext: SemaRef.isConstantEvaluatedContext());
1588	bool RHSuccess = RHS->EvaluateAsInt(Result&: RHSRes, Ctx: SemaRef.getASTContext(),
1589	AllowSideEffects: Expr::SE_AllowSideEffects,
1590	InConstantContext: SemaRef.isConstantEvaluatedContext());
1591
1592	// Don't warn if the one known value is a representable
1593	// in the type of both expressions.
1594	if (LHSSuccess != RHSuccess) {
1595	Expr::EvalResult &Res = LHSSuccess ? LHSRes : RHSRes;
1596	if (IsSingleCodeUnitCP(LHSType, Res.Val.getInt()) &&
1597	IsSingleCodeUnitCP(RHSType, Res.Val.getInt()))
1598	return;
1599	}
1600
1601	if (!LHSSuccess || !RHSuccess) {
1602	SemaRef.Diag(Loc, DiagID: diag::warn_comparison_unicode_mixed_types)
1603	<< LHS->getSourceRange() << RHS->getSourceRange() << LHSType
1604	<< RHSType;
1605	return;
1606	}
1607
1608	llvm::APSInt LHSValue(32);
1609	LHSValue = LHSRes.Val.getInt();
1610	llvm::APSInt RHSValue(32);
1611	RHSValue = RHSRes.Val.getInt();
1612
1613	bool LHSSafe = IsSingleCodeUnitCP(LHSType, LHSValue);
1614	bool RHSSafe = IsSingleCodeUnitCP(RHSType, RHSValue);
1615	if (LHSSafe && RHSSafe)
1616	return;
1617
1618	SemaRef.Diag(Loc, DiagID: diag::warn_comparison_unicode_mixed_types_constant)
1619	<< LHS->getSourceRange() << RHS->getSourceRange() << LHSType << RHSType
1620	<< FormatUTFCodeUnitAsCodepoint(Value: LHSValue.getExtValue(), T: LHSType)
1621	<< FormatUTFCodeUnitAsCodepoint(Value: RHSValue.getExtValue(), T: RHSType);
1622	return;
1623	}
1624
1625	if (SemaRef.getASTContext().hasSameType(T1: LHSType, T2: RHSType))
1626	return;
1627
1628	SemaRef.Diag(Loc, DiagID: diag::warn_arith_conv_mixed_unicode_types)
1629	<< LHS->getSourceRange() << RHS->getSourceRange() << ACK << LHSType
1630	<< RHSType;
1631	}
1632
1633	/// UsualArithmeticConversions - Performs various conversions that are common to
1634	/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this
1635	/// routine returns the first non-arithmetic type found. The client is
1636	/// responsible for emitting appropriate error diagnostics.
1637	QualType Sema::UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS,
1638	SourceLocation Loc,
1639	ArithConvKind ACK) {
1640
1641	checkEnumArithmeticConversions(LHS: LHS.get(), RHS: RHS.get(), Loc, ACK);
1642
1643	CheckUnicodeArithmeticConversions(SemaRef&: *this, LHS: LHS.get(), RHS: RHS.get(), Loc, ACK);
1644
1645	if (ACK != ArithConvKind::CompAssign) {
1646	LHS = UsualUnaryConversions(E: LHS.get());
1647	if (LHS.isInvalid())
1648	return QualType();
1649	}
1650
1651	RHS = UsualUnaryConversions(E: RHS.get());
1652	if (RHS.isInvalid())
1653	return QualType();
1654
1655	// For conversion purposes, we ignore any qualifiers.
1656	// For example, "const float" and "float" are equivalent.
1657	QualType LHSType = LHS.get()->getType().getUnqualifiedType();
1658	QualType RHSType = RHS.get()->getType().getUnqualifiedType();
1659
1660	// For conversion purposes, we ignore any atomic qualifier on the LHS.
1661	if (const AtomicType *AtomicLHS = LHSType->getAs<AtomicType>())
1662	LHSType = AtomicLHS->getValueType();
1663
1664	// If both types are identical, no conversion is needed.
1665	if (Context.hasSameType(T1: LHSType, T2: RHSType))
1666	return Context.getCommonSugaredType(X: LHSType, Y: RHSType);
1667
1668	// If either side is a non-arithmetic type (e.g. a pointer), we are done.
1669	// The caller can deal with this (e.g. pointer + int).
1670	if (!LHSType->isArithmeticType() || !RHSType->isArithmeticType())
1671	return QualType();
1672
1673	// Apply unary and bitfield promotions to the LHS's type.
1674	QualType LHSUnpromotedType = LHSType;
1675	if (Context.isPromotableIntegerType(T: LHSType))
1676	LHSType = Context.getPromotedIntegerType(PromotableType: LHSType);
1677	QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(E: LHS.get());
1678	if (!LHSBitfieldPromoteTy.isNull())
1679	LHSType = LHSBitfieldPromoteTy;
1680	if (LHSType != LHSUnpromotedType && ACK != ArithConvKind::CompAssign)
1681	LHS = ImpCastExprToType(E: LHS.get(), Type: LHSType, CK: CK_IntegralCast);
1682
1683	// If both types are identical, no conversion is needed.
1684	if (Context.hasSameType(T1: LHSType, T2: RHSType))
1685	return Context.getCommonSugaredType(X: LHSType, Y: RHSType);
1686
1687	// At this point, we have two different arithmetic types.
1688
1689	// Diagnose attempts to convert between __ibm128, __float128 and long double
1690	// where such conversions currently can't be handled.
1691	if (unsupportedTypeConversion(S: *this, LHSType, RHSType))
1692	return QualType();
1693
1694	// Handle complex types first (C99 6.3.1.8p1).
1695	if (LHSType->isComplexType() || RHSType->isComplexType())
1696	return handleComplexConversion(S&: *this, LHS, RHS, LHSType, RHSType,
1697	IsCompAssign: ACK == ArithConvKind::CompAssign);
1698
1699	// Now handle "real" floating types (i.e. float, double, long double).
1700	if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType())
1701	return handleFloatConversion(S&: *this, LHS, RHS, LHSType, RHSType,
1702	IsCompAssign: ACK == ArithConvKind::CompAssign);
1703
1704	// Handle GCC complex int extension.
1705	if (LHSType->isComplexIntegerType() || RHSType->isComplexIntegerType())
1706	return handleComplexIntConversion(S&: *this, LHS, RHS, LHSType, RHSType,
1707	IsCompAssign: ACK == ArithConvKind::CompAssign);
1708
1709	if (LHSType->isFixedPointType() || RHSType->isFixedPointType())
1710	return handleFixedPointConversion(S&: *this, LHSTy: LHSType, RHSTy: RHSType);
1711
1712	// Finally, we have two differing integer types.
1713	return handleIntegerConversion<doIntegralCast, doIntegralCast>(
1714	S&: *this, LHS, RHS, LHSType, RHSType, IsCompAssign: ACK == ArithConvKind::CompAssign);
1715	}
1716
1717	//===----------------------------------------------------------------------===//
1718	// Semantic Analysis for various Expression Types
1719	//===----------------------------------------------------------------------===//
1720
1721
1722	ExprResult Sema::ActOnGenericSelectionExpr(
1723	SourceLocation KeyLoc, SourceLocation DefaultLoc, SourceLocation RParenLoc,
1724	bool PredicateIsExpr, void *ControllingExprOrType,
1725	ArrayRef<ParsedType> ArgTypes, ArrayRef<Expr *> ArgExprs) {
1726	unsigned NumAssocs = ArgTypes.size();
1727	assert(NumAssocs == ArgExprs.size());
1728
1729	TypeSourceInfo **Types = new TypeSourceInfo*[NumAssocs];
1730	for (unsigned i = 0; i < NumAssocs; ++i) {
1731	if (ArgTypes[i])
1732	(void) GetTypeFromParser(Ty: ArgTypes[i], TInfo: &Types[i]);
1733	else
1734	Types[i] = nullptr;
1735	}
1736
1737	// If we have a controlling type, we need to convert it from a parsed type
1738	// into a semantic type and then pass that along.
1739	if (!PredicateIsExpr) {
1740	TypeSourceInfo *ControllingType;
1741	(void)GetTypeFromParser(Ty: ParsedType::getFromOpaquePtr(P: ControllingExprOrType),
1742	TInfo: &ControllingType);
1743	assert(ControllingType && "couldn't get the type out of the parser");
1744	ControllingExprOrType = ControllingType;
1745	}
1746
1747	ExprResult ER = CreateGenericSelectionExpr(
1748	KeyLoc, DefaultLoc, RParenLoc, PredicateIsExpr, ControllingExprOrType,
1749	Types: llvm::ArrayRef(Types, NumAssocs), Exprs: ArgExprs);
1750	delete [] Types;
1751	return ER;
1752	}
1753
1754	ExprResult Sema::CreateGenericSelectionExpr(
1755	SourceLocation KeyLoc, SourceLocation DefaultLoc, SourceLocation RParenLoc,
1756	bool PredicateIsExpr, void *ControllingExprOrType,
1757	ArrayRef<TypeSourceInfo *> Types, ArrayRef<Expr *> Exprs) {
1758	unsigned NumAssocs = Types.size();
1759	assert(NumAssocs == Exprs.size());
1760	assert(ControllingExprOrType &&
1761	"Must have either a controlling expression or a controlling type");
1762
1763	Expr *ControllingExpr = nullptr;
1764	TypeSourceInfo *ControllingType = nullptr;
1765	if (PredicateIsExpr) {
1766	// Decay and strip qualifiers for the controlling expression type, and
1767	// handle placeholder type replacement. See committee discussion from WG14
1768	// DR423.
1769	EnterExpressionEvaluationContext Unevaluated(
1770	*this, Sema::ExpressionEvaluationContext::Unevaluated);
1771	ExprResult R = DefaultFunctionArrayLvalueConversion(
1772	E: reinterpret_cast<Expr *>(ControllingExprOrType));
1773	if (R.isInvalid())
1774	return ExprError();
1775	ControllingExpr = R.get();
1776	} else {
1777	// The extension form uses the type directly rather than converting it.
1778	ControllingType = reinterpret_cast<TypeSourceInfo *>(ControllingExprOrType);
1779	if (!ControllingType)
1780	return ExprError();
1781	}
1782
1783	bool TypeErrorFound = false,
1784	IsResultDependent = ControllingExpr
1785	? ControllingExpr->isTypeDependent()
1786	: ControllingType->getType()->isDependentType(),
1787	ContainsUnexpandedParameterPack =
1788	ControllingExpr
1789	? ControllingExpr->containsUnexpandedParameterPack()
1790	: ControllingType->getType()->containsUnexpandedParameterPack();
1791
1792	// The controlling expression is an unevaluated operand, so side effects are
1793	// likely unintended.
1794	if (!inTemplateInstantiation() && !IsResultDependent && ControllingExpr &&
1795	ControllingExpr->HasSideEffects(Ctx: Context, IncludePossibleEffects: false))
1796	Diag(Loc: ControllingExpr->getExprLoc(),
1797	DiagID: diag::warn_side_effects_unevaluated_context);
1798
1799	for (unsigned i = 0; i < NumAssocs; ++i) {
1800	if (Exprs[i]->containsUnexpandedParameterPack())
1801	ContainsUnexpandedParameterPack = true;
1802
1803	if (Types[i]) {
1804	if (Types[i]->getType()->containsUnexpandedParameterPack())
1805	ContainsUnexpandedParameterPack = true;
1806
1807	if (Types[i]->getType()->isDependentType()) {
1808	IsResultDependent = true;
1809	} else {
1810	// We relax the restriction on use of incomplete types and non-object
1811	// types with the type-based extension of _Generic. Allowing incomplete
1812	// objects means those can be used as "tags" for a type-safe way to map
1813	// to a value. Similarly, matching on function types rather than
1814	// function pointer types can be useful. However, the restriction on VM
1815	// types makes sense to retain as there are open questions about how
1816	// the selection can be made at compile time.
1817	//
1818	// C11 6.5.1.1p2 "The type name in a generic association shall specify a
1819	// complete object type other than a variably modified type."
1820	// C2y removed the requirement that an expression form must
1821	// use a complete type, though it's still as-if the type has undergone
1822	// lvalue conversion. We support this as an extension in C23 and
1823	// earlier because GCC does so.
1824	unsigned D = 0;
1825	if (ControllingExpr && Types[i]->getType()->isIncompleteType())
1826	D = LangOpts.C2y ? diag::warn_c2y_compat_assoc_type_incomplete
1827	: diag::ext_assoc_type_incomplete;
1828	else if (ControllingExpr && !Types[i]->getType()->isObjectType())
1829	D = diag::err_assoc_type_nonobject;
1830	else if (Types[i]->getType()->isVariablyModifiedType())
1831	D = diag::err_assoc_type_variably_modified;
1832	else if (ControllingExpr) {
1833	// Because the controlling expression undergoes lvalue conversion,
1834	// array conversion, and function conversion, an association which is
1835	// of array type, function type, or is qualified can never be
1836	// reached. We will warn about this so users are less surprised by
1837	// the unreachable association. However, we don't have to handle
1838	// function types; that's not an object type, so it's handled above.
1839	//
1840	// The logic is somewhat different for C++ because C++ has different
1841	// lvalue to rvalue conversion rules than C. [conv.lvalue]p1 says,
1842	// If T is a non-class type, the type of the prvalue is the cv-
1843	// unqualified version of T. Otherwise, the type of the prvalue is T.
1844	// The result of these rules is that all qualified types in an
1845	// association in C are unreachable, and in C++, only qualified non-
1846	// class types are unreachable.
1847	//
1848	// NB: this does not apply when the first operand is a type rather
1849	// than an expression, because the type form does not undergo
1850	// conversion.
1851	unsigned Reason = 0;
1852	QualType QT = Types[i]->getType();
1853	if (QT->isArrayType())
1854	Reason = 1;
1855	else if (QT.hasQualifiers() &&
1856	(!LangOpts.CPlusPlus || !QT->isRecordType()))
1857	Reason = 2;
1858
1859	if (Reason)
1860	Diag(Loc: Types[i]->getTypeLoc().getBeginLoc(),
1861	DiagID: diag::warn_unreachable_association)
1862	<< QT << (Reason - 1);
1863	}
1864
1865	if (D != 0) {
1866	Diag(Loc: Types[i]->getTypeLoc().getBeginLoc(), DiagID: D)
1867	<< Types[i]->getTypeLoc().getSourceRange() << Types[i]->getType();
1868	if (getDiagnostics().getDiagnosticLevel(
1869	DiagID: D, Loc: Types[i]->getTypeLoc().getBeginLoc()) >=
1870	DiagnosticsEngine::Error)
1871	TypeErrorFound = true;
1872	}
1873
1874	// C11 6.5.1.1p2 "No two generic associations in the same generic
1875	// selection shall specify compatible types."
1876	for (unsigned j = i+1; j < NumAssocs; ++j)
1877	if (Types[j] && !Types[j]->getType()->isDependentType() &&
1878	Context.typesAreCompatible(T1: Types[i]->getType(),
1879	T2: Types[j]->getType())) {
1880	Diag(Loc: Types[j]->getTypeLoc().getBeginLoc(),
1881	DiagID: diag::err_assoc_compatible_types)
1882	<< Types[j]->getTypeLoc().getSourceRange()
1883	<< Types[j]->getType()
1884	<< Types[i]->getType();
1885	Diag(Loc: Types[i]->getTypeLoc().getBeginLoc(),
1886	DiagID: diag::note_compat_assoc)
1887	<< Types[i]->getTypeLoc().getSourceRange()
1888	<< Types[i]->getType();
1889	TypeErrorFound = true;
1890	}
1891	}
1892	}
1893	}
1894	if (TypeErrorFound)
1895	return ExprError();
1896
1897	// If we determined that the generic selection is result-dependent, don't
1898	// try to compute the result expression.
1899	if (IsResultDependent) {
1900	if (ControllingExpr)
1901	return GenericSelectionExpr::Create(Context, GenericLoc: KeyLoc, ControllingExpr,
1902	AssocTypes: Types, AssocExprs: Exprs, DefaultLoc, RParenLoc,
1903	ContainsUnexpandedParameterPack);
1904	return GenericSelectionExpr::Create(Context, GenericLoc: KeyLoc, ControllingType, AssocTypes: Types,
1905	AssocExprs: Exprs, DefaultLoc, RParenLoc,
1906	ContainsUnexpandedParameterPack);
1907	}
1908
1909	SmallVector<unsigned, 1> CompatIndices;
1910	unsigned DefaultIndex = std::numeric_limits<unsigned>::max();
1911	// Look at the canonical type of the controlling expression in case it was a
1912	// deduced type like __auto_type. However, when issuing diagnostics, use the
1913	// type the user wrote in source rather than the canonical one.
1914	for (unsigned i = 0; i < NumAssocs; ++i) {
1915	if (!Types[i])
1916	DefaultIndex = i;
1917	else if (ControllingExpr &&
1918	Context.typesAreCompatible(
1919	T1: ControllingExpr->getType().getCanonicalType(),
1920	T2: Types[i]->getType()))
1921	CompatIndices.push_back(Elt: i);
1922	else if (ControllingType &&
1923	Context.typesAreCompatible(
1924	T1: ControllingType->getType().getCanonicalType(),
1925	T2: Types[i]->getType()))
1926	CompatIndices.push_back(Elt: i);
1927	}
1928
1929	auto GetControllingRangeAndType = [](Expr *ControllingExpr,
1930	TypeSourceInfo *ControllingType) {
1931	// We strip parens here because the controlling expression is typically
1932	// parenthesized in macro definitions.
1933	if (ControllingExpr)
1934	ControllingExpr = ControllingExpr->IgnoreParens();
1935
1936	SourceRange SR = ControllingExpr
1937	? ControllingExpr->getSourceRange()
1938	: ControllingType->getTypeLoc().getSourceRange();
1939	QualType QT = ControllingExpr ? ControllingExpr->getType()
1940	: ControllingType->getType();
1941
1942	return std::make_pair(x&: SR, y&: QT);
1943	};
1944
1945	// C11 6.5.1.1p2 "The controlling expression of a generic selection shall have
1946	// type compatible with at most one of the types named in its generic
1947	// association list."
1948	if (CompatIndices.size() > 1) {
1949	auto P = GetControllingRangeAndType(ControllingExpr, ControllingType);
1950	SourceRange SR = P.first;
1951	Diag(Loc: SR.getBegin(), DiagID: diag::err_generic_sel_multi_match)
1952	<< SR << P.second << (unsigned)CompatIndices.size();
1953	for (unsigned I : CompatIndices) {
1954	Diag(Loc: Types[I]->getTypeLoc().getBeginLoc(),
1955	DiagID: diag::note_compat_assoc)
1956	<< Types[I]->getTypeLoc().getSourceRange()
1957	<< Types[I]->getType();
1958	}
1959	return ExprError();
1960	}
1961
1962	// C11 6.5.1.1p2 "If a generic selection has no default generic association,
1963	// its controlling expression shall have type compatible with exactly one of
1964	// the types named in its generic association list."
1965	if (DefaultIndex == std::numeric_limits<unsigned>::max() &&
1966	CompatIndices.size() == 0) {
1967	auto P = GetControllingRangeAndType(ControllingExpr, ControllingType);
1968	SourceRange SR = P.first;
1969	Diag(Loc: SR.getBegin(), DiagID: diag::err_generic_sel_no_match) << SR << P.second;
1970	return ExprError();
1971	}
1972
1973	// C11 6.5.1.1p3 "If a generic selection has a generic association with a
1974	// type name that is compatible with the type of the controlling expression,
1975	// then the result expression of the generic selection is the expression
1976	// in that generic association. Otherwise, the result expression of the
1977	// generic selection is the expression in the default generic association."
1978	unsigned ResultIndex =
1979	CompatIndices.size() ? CompatIndices[0] : DefaultIndex;
1980
1981	if (ControllingExpr) {
1982	return GenericSelectionExpr::Create(
1983	Context, GenericLoc: KeyLoc, ControllingExpr, AssocTypes: Types, AssocExprs: Exprs, DefaultLoc, RParenLoc,
1984	ContainsUnexpandedParameterPack, ResultIndex);
1985	}
1986	return GenericSelectionExpr::Create(
1987	Context, GenericLoc: KeyLoc, ControllingType, AssocTypes: Types, AssocExprs: Exprs, DefaultLoc, RParenLoc,
1988	ContainsUnexpandedParameterPack, ResultIndex);
1989	}
1990
1991	static PredefinedIdentKind getPredefinedExprKind(tok::TokenKind Kind) {
1992	switch (Kind) {
1993	default:
1994	llvm_unreachable("unexpected TokenKind");
1995	case tok::kw___func__:
1996	return PredefinedIdentKind::Func; // [C99 6.4.2.2]
1997	case tok::kw___FUNCTION__:
1998	return PredefinedIdentKind::Function;
1999	case tok::kw___FUNCDNAME__:
2000	return PredefinedIdentKind::FuncDName; // [MS]
2001	case tok::kw___FUNCSIG__:
2002	return PredefinedIdentKind::FuncSig; // [MS]
2003	case tok::kw_L__FUNCTION__:
2004	return PredefinedIdentKind::LFunction; // [MS]
2005	case tok::kw_L__FUNCSIG__:
2006	return PredefinedIdentKind::LFuncSig; // [MS]
2007	case tok::kw___PRETTY_FUNCTION__:
2008	return PredefinedIdentKind::PrettyFunction; // [GNU]
2009	}
2010	}
2011
2012	/// getPredefinedExprDecl - Returns Decl of a given DeclContext that can be used
2013	/// to determine the value of a PredefinedExpr. This can be either a
2014	/// block, lambda, captured statement, function, otherwise a nullptr.
2015	static Decl *getPredefinedExprDecl(DeclContext *DC) {
2016	while (DC && !isa<BlockDecl, CapturedDecl, FunctionDecl, ObjCMethodDecl>(Val: DC))
2017	DC = DC->getParent();
2018	return cast_or_null<Decl>(Val: DC);
2019	}
2020
2021	/// getUDSuffixLoc - Create a SourceLocation for a ud-suffix, given the
2022	/// location of the token and the offset of the ud-suffix within it.
2023	static SourceLocation getUDSuffixLoc(Sema &S, SourceLocation TokLoc,
2024	unsigned Offset) {
2025	return Lexer::AdvanceToTokenCharacter(TokStart: TokLoc, Characters: Offset, SM: S.getSourceManager(),
2026	LangOpts: S.getLangOpts());
2027	}
2028
2029	/// BuildCookedLiteralOperatorCall - A user-defined literal was found. Look up
2030	/// the corresponding cooked (non-raw) literal operator, and build a call to it.
2031	static ExprResult BuildCookedLiteralOperatorCall(Sema &S, Scope *Scope,
2032	IdentifierInfo *UDSuffix,
2033	SourceLocation UDSuffixLoc,
2034	ArrayRef<Expr*> Args,
2035	SourceLocation LitEndLoc) {
2036	assert(Args.size() <= 2 && "too many arguments for literal operator");
2037
2038	QualType ArgTy[2];
2039	for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) {
2040	ArgTy[ArgIdx] = Args[ArgIdx]->getType();
2041	if (ArgTy[ArgIdx]->isArrayType())
2042	ArgTy[ArgIdx] = S.Context.getArrayDecayedType(T: ArgTy[ArgIdx]);
2043	}
2044
2045	DeclarationName OpName =
2046	S.Context.DeclarationNames.getCXXLiteralOperatorName(II: UDSuffix);
2047	DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
2048	OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
2049
2050	LookupResult R(S, OpName, UDSuffixLoc, Sema::LookupOrdinaryName);
2051	if (S.LookupLiteralOperator(S: Scope, R, ArgTys: llvm::ArrayRef(ArgTy, Args.size()),
2052	/*AllowRaw*/ false, /*AllowTemplate*/ false,
2053	/*AllowStringTemplatePack*/ AllowStringTemplate: false,
2054	/*DiagnoseMissing*/ true) == Sema::LOLR_Error)
2055	return ExprError();
2056
2057	return S.BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args, LitEndLoc);
2058	}
2059
2060	ExprResult Sema::ActOnUnevaluatedStringLiteral(ArrayRef<Token> StringToks) {
2061	// StringToks needs backing storage as it doesn't hold array elements itself
2062	std::vector<Token> ExpandedToks;
2063	if (getLangOpts().MicrosoftExt)
2064	StringToks = ExpandedToks = ExpandFunctionLocalPredefinedMacros(Toks: StringToks);
2065
2066	StringLiteralParser Literal(StringToks, PP,
2067	StringLiteralEvalMethod::Unevaluated);
2068	if (Literal.hadError)
2069	return ExprError();
2070
2071	SmallVector<SourceLocation, 4> StringTokLocs;
2072	for (const Token &Tok : StringToks)
2073	StringTokLocs.push_back(Elt: Tok.getLocation());
2074
2075	StringLiteral *Lit = StringLiteral::Create(Ctx: Context, Str: Literal.GetString(),
2076	Kind: StringLiteralKind::Unevaluated,
2077	Pascal: false, Ty: {}, Locs: StringTokLocs);
2078
2079	if (!Literal.getUDSuffix().empty()) {
2080	SourceLocation UDSuffixLoc =
2081	getUDSuffixLoc(S&: *this, TokLoc: StringTokLocs[Literal.getUDSuffixToken()],
2082	Offset: Literal.getUDSuffixOffset());
2083	return ExprError(Diag(Loc: UDSuffixLoc, DiagID: diag::err_invalid_string_udl));
2084	}
2085
2086	return Lit;
2087	}
2088
2089	std::vector<Token>
2090	Sema::ExpandFunctionLocalPredefinedMacros(ArrayRef<Token> Toks) {
2091	// MSVC treats some predefined identifiers (e.g. __FUNCTION__) as function
2092	// local macros that expand to string literals that may be concatenated.
2093	// These macros are expanded here (in Sema), because StringLiteralParser
2094	// (in Lex) doesn't know the enclosing function (because it hasn't been
2095	// parsed yet).
2096	assert(getLangOpts().MicrosoftExt);
2097
2098	// Note: Although function local macros are defined only inside functions,
2099	// we ensure a valid `CurrentDecl` even outside of a function. This allows
2100	// expansion of macros into empty string literals without additional checks.
2101	Decl *CurrentDecl = getPredefinedExprDecl(DC: CurContext);
2102	if (!CurrentDecl)
2103	CurrentDecl = Context.getTranslationUnitDecl();
2104
2105	std::vector<Token> ExpandedToks;
2106	ExpandedToks.reserve(n: Toks.size());
2107	for (const Token &Tok : Toks) {
2108	if (!isFunctionLocalStringLiteralMacro(K: Tok.getKind(), LO: getLangOpts())) {
2109	assert(tok::isStringLiteral(Tok.getKind()));
2110	ExpandedToks.emplace_back(args: Tok);
2111	continue;
2112	}
2113	if (isa<TranslationUnitDecl>(Val: CurrentDecl))
2114	Diag(Loc: Tok.getLocation(), DiagID: diag::ext_predef_outside_function);
2115	// Stringify predefined expression
2116	Diag(Loc: Tok.getLocation(), DiagID: diag::ext_string_literal_from_predefined)
2117	<< Tok.getKind();
2118	SmallString<64> Str;
2119	llvm::raw_svector_ostream OS(Str);
2120	Token &Exp = ExpandedToks.emplace_back();
2121	Exp.startToken();
2122	if (Tok.getKind() == tok::kw_L__FUNCTION__ ||
2123	Tok.getKind() == tok::kw_L__FUNCSIG__) {
2124	OS << 'L';
2125	Exp.setKind(tok::wide_string_literal);
2126	} else {
2127	Exp.setKind(tok::string_literal);
2128	}
2129	OS << '"'
2130	<< Lexer::Stringify(Str: PredefinedExpr::ComputeName(
2131	IK: getPredefinedExprKind(Kind: Tok.getKind()), CurrentDecl))
2132	<< '"';
2133	PP.CreateString(Str: OS.str(), Tok&: Exp, ExpansionLocStart: Tok.getLocation(), ExpansionLocEnd: Tok.getEndLoc());
2134	}
2135	return ExpandedToks;
2136	}
2137
2138	ExprResult
2139	Sema::ActOnStringLiteral(ArrayRef<Token> StringToks, Scope *UDLScope) {
2140	assert(!StringToks.empty() && "Must have at least one string!");
2141
2142	// StringToks needs backing storage as it doesn't hold array elements itself
2143	std::vector<Token> ExpandedToks;
2144	if (getLangOpts().MicrosoftExt)
2145	StringToks = ExpandedToks = ExpandFunctionLocalPredefinedMacros(Toks: StringToks);
2146
2147	StringLiteralParser Literal(StringToks, PP);
2148	if (Literal.hadError)
2149	return ExprError();
2150
2151	SmallVector<SourceLocation, 4> StringTokLocs;
2152	for (const Token &Tok : StringToks)
2153	StringTokLocs.push_back(Elt: Tok.getLocation());
2154
2155	QualType CharTy = Context.CharTy;
2156	StringLiteralKind Kind = StringLiteralKind::Ordinary;
2157	if (Literal.isWide()) {
2158	CharTy = Context.getWideCharType();
2159	Kind = StringLiteralKind::Wide;
2160	} else if (Literal.isUTF8()) {
2161	if (getLangOpts().Char8)
2162	CharTy = Context.Char8Ty;
2163	else if (getLangOpts().C23)
2164	CharTy = Context.UnsignedCharTy;
2165	Kind = StringLiteralKind::UTF8;
2166	} else if (Literal.isUTF16()) {
2167	CharTy = Context.Char16Ty;
2168	Kind = StringLiteralKind::UTF16;
2169	} else if (Literal.isUTF32()) {
2170	CharTy = Context.Char32Ty;
2171	Kind = StringLiteralKind::UTF32;
2172	} else if (Literal.isPascal()) {
2173	CharTy = Context.UnsignedCharTy;
2174	}
2175
2176	// Warn on u8 string literals before C++20 and C23, whose type
2177	// was an array of char before but becomes an array of char8_t.
2178	// In C++20, it cannot be used where a pointer to char is expected.
2179	// In C23, it might have an unexpected value if char was signed.
2180	if (Kind == StringLiteralKind::UTF8 &&
2181	(getLangOpts().CPlusPlus
2182	? !getLangOpts().CPlusPlus20 && !getLangOpts().Char8
2183	: !getLangOpts().C23)) {
2184	Diag(Loc: StringTokLocs.front(), DiagID: getLangOpts().CPlusPlus
2185	? diag::warn_cxx20_compat_utf8_string
2186	: diag::warn_c23_compat_utf8_string);
2187
2188	// Create removals for all 'u8' prefixes in the string literal(s). This
2189	// ensures C++20/C23 compatibility (but may change the program behavior when
2190	// built by non-Clang compilers for which the execution character set is
2191	// not always UTF-8).
2192	auto RemovalDiag = PDiag(DiagID: diag::note_cxx20_c23_compat_utf8_string_remove_u8);
2193	SourceLocation RemovalDiagLoc;
2194	for (const Token &Tok : StringToks) {
2195	if (Tok.getKind() == tok::utf8_string_literal) {
2196	if (RemovalDiagLoc.isInvalid())
2197	RemovalDiagLoc = Tok.getLocation();
2198	RemovalDiag << FixItHint::CreateRemoval(RemoveRange: CharSourceRange::getCharRange(
2199	B: Tok.getLocation(),
2200	E: Lexer::AdvanceToTokenCharacter(TokStart: Tok.getLocation(), Characters: 2,
2201	SM: getSourceManager(), LangOpts: getLangOpts())));
2202	}
2203	}
2204	Diag(Loc: RemovalDiagLoc, PD: RemovalDiag);
2205	}
2206
2207	QualType StrTy =
2208	Context.getStringLiteralArrayType(EltTy: CharTy, Length: Literal.GetNumStringChars());
2209
2210	// Pass &StringTokLocs[0], StringTokLocs.size() to factory!
2211	StringLiteral *Lit = StringLiteral::Create(
2212	Ctx: Context, Str: Literal.GetString(), Kind, Pascal: Literal.Pascal, Ty: StrTy, Locs: StringTokLocs);
2213	if (Literal.getUDSuffix().empty())
2214	return Lit;
2215
2216	// We're building a user-defined literal.
2217	IdentifierInfo *UDSuffix = &Context.Idents.get(Name: Literal.getUDSuffix());
2218	SourceLocation UDSuffixLoc =
2219	getUDSuffixLoc(S&: *this, TokLoc: StringTokLocs[Literal.getUDSuffixToken()],
2220	Offset: Literal.getUDSuffixOffset());
2221
2222	// Make sure we're allowed user-defined literals here.
2223	if (!UDLScope)
2224	return ExprError(Diag(Loc: UDSuffixLoc, DiagID: diag::err_invalid_string_udl));
2225
2226	// C++11 [lex.ext]p5: The literal L is treated as a call of the form
2227	// operator "" X (str, len)
2228	QualType SizeType = Context.getSizeType();
2229
2230	DeclarationName OpName =
2231	Context.DeclarationNames.getCXXLiteralOperatorName(II: UDSuffix);
2232	DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
2233	OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
2234
2235	QualType ArgTy[] = {
2236	Context.getArrayDecayedType(T: StrTy), SizeType
2237	};
2238
2239	LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName);
2240	switch (LookupLiteralOperator(S: UDLScope, R, ArgTys: ArgTy,
2241	/*AllowRaw*/ false, /*AllowTemplate*/ true,
2242	/*AllowStringTemplatePack*/ AllowStringTemplate: true,
2243	/*DiagnoseMissing*/ true, StringLit: Lit)) {
2244
2245	case LOLR_Cooked: {
2246	llvm::APInt Len(Context.getIntWidth(T: SizeType), Literal.GetNumStringChars());
2247	IntegerLiteral *LenArg = IntegerLiteral::Create(C: Context, V: Len, type: SizeType,
2248	l: StringTokLocs[0]);
2249	Expr *Args[] = { Lit, LenArg };
2250
2251	return BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args, LitEndLoc: StringTokLocs.back());
2252	}
2253
2254	case LOLR_Template: {
2255	TemplateArgumentListInfo ExplicitArgs;
2256	TemplateArgument Arg(Lit, /*IsCanonical=*/false);
2257	TemplateArgumentLocInfo ArgInfo(Lit);
2258	ExplicitArgs.addArgument(Loc: TemplateArgumentLoc(Arg, ArgInfo));
2259	return BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args: {}, LitEndLoc: StringTokLocs.back(),
2260	ExplicitTemplateArgs: &ExplicitArgs);
2261	}
2262
2263	case LOLR_StringTemplatePack: {
2264	TemplateArgumentListInfo ExplicitArgs;
2265
2266	unsigned CharBits = Context.getIntWidth(T: CharTy);
2267	bool CharIsUnsigned = CharTy->isUnsignedIntegerType();
2268	llvm::APSInt Value(CharBits, CharIsUnsigned);
2269
2270	TemplateArgument TypeArg(CharTy);
2271	TemplateArgumentLocInfo TypeArgInfo(Context.getTrivialTypeSourceInfo(T: CharTy));
2272	ExplicitArgs.addArgument(Loc: TemplateArgumentLoc(TypeArg, TypeArgInfo));
2273
2274	for (unsigned I = 0, N = Lit->getLength(); I != N; ++I) {
2275	Value = Lit->getCodeUnit(i: I);
2276	TemplateArgument Arg(Context, Value, CharTy);
2277	TemplateArgumentLocInfo ArgInfo;
2278	ExplicitArgs.addArgument(Loc: TemplateArgumentLoc(Arg, ArgInfo));
2279	}
2280	return BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args: {}, LitEndLoc: StringTokLocs.back(),
2281	ExplicitTemplateArgs: &ExplicitArgs);
2282	}
2283	case LOLR_Raw:
2284	case LOLR_ErrorNoDiagnostic:
2285	llvm_unreachable("unexpected literal operator lookup result");
2286	case LOLR_Error:
2287	return ExprError();
2288	}
2289	llvm_unreachable("unexpected literal operator lookup result");
2290	}
2291
2292	DeclRefExpr *
2293	Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
2294	SourceLocation Loc,
2295	const CXXScopeSpec *SS) {
2296	DeclarationNameInfo NameInfo(D->getDeclName(), Loc);
2297	return BuildDeclRefExpr(D, Ty, VK, NameInfo, SS);
2298	}
2299
2300	DeclRefExpr *
2301	Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
2302	const DeclarationNameInfo &NameInfo,
2303	const CXXScopeSpec *SS, NamedDecl *FoundD,
2304	SourceLocation TemplateKWLoc,
2305	const TemplateArgumentListInfo *TemplateArgs) {
2306	NestedNameSpecifierLoc NNS =
2307	SS ? SS->getWithLocInContext(Context) : NestedNameSpecifierLoc();
2308	return BuildDeclRefExpr(D, Ty, VK, NameInfo, NNS, FoundD, TemplateKWLoc,
2309	TemplateArgs);
2310	}
2311
2312	// CUDA/HIP: Check whether a captured reference variable is referencing a
2313	// host variable in a device or host device lambda.
2314	static bool isCapturingReferenceToHostVarInCUDADeviceLambda(const Sema &S,
2315	VarDecl *VD) {
2316	if (!S.getLangOpts().CUDA || !VD->hasInit())
2317	return false;
2318	assert(VD->getType()->isReferenceType());
2319
2320	// Check whether the reference variable is referencing a host variable.
2321	auto *DRE = dyn_cast<DeclRefExpr>(Val: VD->getInit());
2322	if (!DRE)
2323	return false;
2324	auto *Referee = dyn_cast<VarDecl>(Val: DRE->getDecl());
2325	if (!Referee || !Referee->hasGlobalStorage() ||
2326	Referee->hasAttr<CUDADeviceAttr>())
2327	return false;
2328
2329	// Check whether the current function is a device or host device lambda.
2330	// Check whether the reference variable is a capture by getDeclContext()
2331	// since refersToEnclosingVariableOrCapture() is not ready at this point.
2332	auto *MD = dyn_cast_or_null<CXXMethodDecl>(Val: S.CurContext);
2333	if (MD && MD->getParent()->isLambda() &&
2334	MD->getOverloadedOperator() == OO_Call && MD->hasAttr<CUDADeviceAttr>() &&
2335	VD->getDeclContext() != MD)
2336	return true;
2337
2338	return false;
2339	}
2340
2341	NonOdrUseReason Sema::getNonOdrUseReasonInCurrentContext(ValueDecl *D) {
2342	// A declaration named in an unevaluated operand never constitutes an odr-use.
2343	if (isUnevaluatedContext())
2344	return NOUR_Unevaluated;
2345
2346	// C++2a [basic.def.odr]p4:
2347	// A variable x whose name appears as a potentially-evaluated expression e
2348	// is odr-used by e unless [...] x is a reference that is usable in
2349	// constant expressions.
2350	// CUDA/HIP:
2351	// If a reference variable referencing a host variable is captured in a
2352	// device or host device lambda, the value of the referee must be copied
2353	// to the capture and the reference variable must be treated as odr-use
2354	// since the value of the referee is not known at compile time and must
2355	// be loaded from the captured.
2356	if (VarDecl *VD = dyn_cast<VarDecl>(Val: D)) {
2357	if (VD->getType()->isReferenceType() &&
2358	!(getLangOpts().OpenMP && OpenMP().isOpenMPCapturedDecl(D)) &&
2359	!isCapturingReferenceToHostVarInCUDADeviceLambda(S: *this, VD) &&
2360	VD->isUsableInConstantExpressions(C: Context))
2361	return NOUR_Constant;
2362	}
2363
2364	// All remaining non-variable cases constitute an odr-use. For variables, we
2365	// need to wait and see how the expression is used.
2366	return NOUR_None;
2367	}
2368
2369	DeclRefExpr *
2370	Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
2371	const DeclarationNameInfo &NameInfo,
2372	NestedNameSpecifierLoc NNS, NamedDecl *FoundD,
2373	SourceLocation TemplateKWLoc,
2374	const TemplateArgumentListInfo *TemplateArgs) {
2375	bool RefersToCapturedVariable = isa<VarDecl, BindingDecl>(Val: D) &&
2376	NeedToCaptureVariable(Var: D, Loc: NameInfo.getLoc());
2377
2378	DeclRefExpr *E = DeclRefExpr::Create(
2379	Context, QualifierLoc: NNS, TemplateKWLoc, D, RefersToEnclosingVariableOrCapture: RefersToCapturedVariable, NameInfo, T: Ty,
2380	VK, FoundD, TemplateArgs, NOUR: getNonOdrUseReasonInCurrentContext(D));
2381	MarkDeclRefReferenced(E);
2382
2383	// C++ [except.spec]p17:
2384	// An exception-specification is considered to be needed when:
2385	// - in an expression, the function is the unique lookup result or
2386	// the selected member of a set of overloaded functions.
2387	//
2388	// We delay doing this until after we've built the function reference and
2389	// marked it as used so that:
2390	// a) if the function is defaulted, we get errors from defining it before /
2391	// instead of errors from computing its exception specification, and
2392	// b) if the function is a defaulted comparison, we can use the body we
2393	// build when defining it as input to the exception specification
2394	// computation rather than computing a new body.
2395	if (const auto *FPT = Ty->getAs<FunctionProtoType>()) {
2396	if (isUnresolvedExceptionSpec(ESpecType: FPT->getExceptionSpecType())) {
2397	if (const auto *NewFPT = ResolveExceptionSpec(Loc: NameInfo.getLoc(), FPT))
2398	E->setType(Context.getQualifiedType(T: NewFPT, Qs: Ty.getQualifiers()));
2399	}
2400	}
2401
2402	if (getLangOpts().ObjCWeak && isa<VarDecl>(Val: D) &&
2403	Ty.getObjCLifetime() == Qualifiers::OCL_Weak && !isUnevaluatedContext() &&
2404	!Diags.isIgnored(DiagID: diag::warn_arc_repeated_use_of_weak, Loc: E->getBeginLoc()))
2405	getCurFunction()->recordUseOfWeak(E);
2406
2407	const auto *FD = dyn_cast<FieldDecl>(Val: D);
2408	if (const auto *IFD = dyn_cast<IndirectFieldDecl>(Val: D))
2409	FD = IFD->getAnonField();
2410	if (FD) {
2411	UnusedPrivateFields.remove(X: FD);
2412	// Just in case we're building an illegal pointer-to-member.
2413	if (FD->isBitField())
2414	E->setObjectKind(OK_BitField);
2415	}
2416
2417	// C++ [expr.prim]/8: The expression [...] is a bit-field if the identifier
2418	// designates a bit-field.
2419	if (const auto *BD = dyn_cast<BindingDecl>(Val: D))
2420	if (const auto *BE = BD->getBinding())
2421	E->setObjectKind(BE->getObjectKind());
2422
2423	return E;
2424	}
2425
2426	void
2427	Sema::DecomposeUnqualifiedId(const UnqualifiedId &Id,
2428	TemplateArgumentListInfo &Buffer,
2429	DeclarationNameInfo &NameInfo,
2430	const TemplateArgumentListInfo *&TemplateArgs) {
2431	if (Id.getKind() == UnqualifiedIdKind::IK_TemplateId) {
2432	Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc);
2433	Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc);
2434
2435	ASTTemplateArgsPtr TemplateArgsPtr(Id.TemplateId->getTemplateArgs(),
2436	Id.TemplateId->NumArgs);
2437	translateTemplateArguments(In: TemplateArgsPtr, Out&: Buffer);
2438
2439	TemplateName TName = Id.TemplateId->Template.get();
2440	SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc;
2441	NameInfo = Context.getNameForTemplate(Name: TName, NameLoc: TNameLoc);
2442	TemplateArgs = &Buffer;
2443	} else {
2444	NameInfo = GetNameFromUnqualifiedId(Name: Id);
2445	TemplateArgs = nullptr;
2446	}
2447	}
2448
2449	bool Sema::DiagnoseDependentMemberLookup(const LookupResult &R) {
2450	// During a default argument instantiation the CurContext points
2451	// to a CXXMethodDecl; but we can't apply a this-> fixit inside a
2452	// function parameter list, hence add an explicit check.
2453	bool isDefaultArgument =
2454	!CodeSynthesisContexts.empty() &&
2455	CodeSynthesisContexts.back().Kind ==
2456	CodeSynthesisContext::DefaultFunctionArgumentInstantiation;
2457	const auto *CurMethod = dyn_cast<CXXMethodDecl>(Val: CurContext);
2458	bool isInstance = CurMethod && CurMethod->isInstance() &&
2459	R.getNamingClass() == CurMethod->getParent() &&
2460	!isDefaultArgument;
2461
2462	// There are two ways we can find a class-scope declaration during template
2463	// instantiation that we did not find in the template definition: if it is a
2464	// member of a dependent base class, or if it is declared after the point of
2465	// use in the same class. Distinguish these by comparing the class in which
2466	// the member was found to the naming class of the lookup.
2467	unsigned DiagID = diag::err_found_in_dependent_base;
2468	unsigned NoteID = diag::note_member_declared_at;
2469	if (R.getRepresentativeDecl()->getDeclContext()->Equals(DC: R.getNamingClass())) {
2470	DiagID = getLangOpts().MSVCCompat ? diag::ext_found_later_in_class
2471	: diag::err_found_later_in_class;
2472	} else if (getLangOpts().MSVCCompat) {
2473	DiagID = diag::ext_found_in_dependent_base;
2474	NoteID = diag::note_dependent_member_use;
2475	}
2476
2477	if (isInstance) {
2478	// Give a code modification hint to insert 'this->'.
2479	Diag(Loc: R.getNameLoc(), DiagID)
2480	<< R.getLookupName()
2481	<< FixItHint::CreateInsertion(InsertionLoc: R.getNameLoc(), Code: "this->");
2482	CheckCXXThisCapture(Loc: R.getNameLoc());
2483	} else {
2484	// FIXME: Add a FixItHint to insert 'Base::' or 'Derived::' (assuming
2485	// they're not shadowed).
2486	Diag(Loc: R.getNameLoc(), DiagID) << R.getLookupName();
2487	}
2488
2489	for (const NamedDecl *D : R)
2490	Diag(Loc: D->getLocation(), DiagID: NoteID);
2491
2492	// Return true if we are inside a default argument instantiation
2493	// and the found name refers to an instance member function, otherwise
2494	// the caller will try to create an implicit member call and this is wrong
2495	// for default arguments.
2496	//
2497	// FIXME: Is this special case necessary? We could allow the caller to
2498	// diagnose this.
2499	if (isDefaultArgument && ((*R.begin())->isCXXInstanceMember())) {
2500	Diag(Loc: R.getNameLoc(), DiagID: diag::err_member_call_without_object) << 0;
2501	return true;
2502	}
2503
2504	// Tell the callee to try to recover.
2505	return false;
2506	}
2507
2508	bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
2509	CorrectionCandidateCallback &CCC,
2510	TemplateArgumentListInfo *ExplicitTemplateArgs,
2511	ArrayRef<Expr *> Args, DeclContext *LookupCtx) {
2512	DeclarationName Name = R.getLookupName();
2513	SourceRange NameRange = R.getLookupNameInfo().getSourceRange();
2514
2515	unsigned diagnostic = diag::err_undeclared_var_use;
2516	unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest;
2517	if (Name.getNameKind() == DeclarationName::CXXOperatorName ||
2518	Name.getNameKind() == DeclarationName::CXXLiteralOperatorName ||
2519	Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
2520	diagnostic = diag::err_undeclared_use;
2521	diagnostic_suggest = diag::err_undeclared_use_suggest;
2522	}
2523
2524	// If the original lookup was an unqualified lookup, fake an
2525	// unqualified lookup. This is useful when (for example) the
2526	// original lookup would not have found something because it was a
2527	// dependent name.
2528	DeclContext *DC =
2529	LookupCtx ? LookupCtx : (SS.isEmpty() ? CurContext : nullptr);
2530	while (DC) {
2531	if (isa<CXXRecordDecl>(Val: DC)) {
2532	if (ExplicitTemplateArgs) {
2533	if (LookupTemplateName(
2534	R, S, SS, ObjectType: Context.getRecordType(Decl: cast<CXXRecordDecl>(Val: DC)),
2535	/*EnteringContext*/ false, RequiredTemplate: TemplateNameIsRequired,
2536	/*RequiredTemplateKind*/ ATK: nullptr, /*AllowTypoCorrection*/ true))
2537	return true;
2538	} else {
2539	LookupQualifiedName(R, LookupCtx: DC);
2540	}
2541
2542	if (!R.empty()) {
2543	// Don't give errors about ambiguities in this lookup.
2544	R.suppressDiagnostics();
2545
2546	// If there's a best viable function among the results, only mention
2547	// that one in the notes.
2548	OverloadCandidateSet Candidates(R.getNameLoc(),
2549	OverloadCandidateSet::CSK_Normal);
2550	AddOverloadedCallCandidates(R, ExplicitTemplateArgs, Args, CandidateSet&: Candidates);
2551	OverloadCandidateSet::iterator Best;
2552	if (Candidates.BestViableFunction(S&: *this, Loc: R.getNameLoc(), Best) ==
2553	OR_Success) {
2554	R.clear();
2555	R.addDecl(D: Best->FoundDecl.getDecl(), AS: Best->FoundDecl.getAccess());
2556	R.resolveKind();
2557	}
2558
2559	return DiagnoseDependentMemberLookup(R);
2560	}
2561
2562	R.clear();
2563	}
2564
2565	DC = DC->getLookupParent();
2566	}
2567
2568	// We didn't find anything, so try to correct for a typo.
2569	TypoCorrection Corrected;
2570	if (S && (Corrected =
2571	CorrectTypo(Typo: R.getLookupNameInfo(), LookupKind: R.getLookupKind(), S, SS: &SS,
2572	CCC, Mode: CorrectTypoKind::ErrorRecovery, MemberContext: LookupCtx))) {
2573	std::string CorrectedStr(Corrected.getAsString(LO: getLangOpts()));
2574	bool DroppedSpecifier =
2575	Corrected.WillReplaceSpecifier() && Name.getAsString() == CorrectedStr;
2576	R.setLookupName(Corrected.getCorrection());
2577
2578	bool AcceptableWithRecovery = false;
2579	bool AcceptableWithoutRecovery = false;
2580	NamedDecl *ND = Corrected.getFoundDecl();
2581	if (ND) {
2582	if (Corrected.isOverloaded()) {
2583	OverloadCandidateSet OCS(R.getNameLoc(),
2584	OverloadCandidateSet::CSK_Normal);
2585	OverloadCandidateSet::iterator Best;
2586	for (NamedDecl *CD : Corrected) {
2587	if (FunctionTemplateDecl *FTD =
2588	dyn_cast<FunctionTemplateDecl>(Val: CD))
2589	AddTemplateOverloadCandidate(
2590	FunctionTemplate: FTD, FoundDecl: DeclAccessPair::make(D: FTD, AS: AS_none), ExplicitTemplateArgs,
2591	Args, CandidateSet&: OCS);
2592	else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Val: CD))
2593	if (!ExplicitTemplateArgs || ExplicitTemplateArgs->size() == 0)
2594	AddOverloadCandidate(Function: FD, FoundDecl: DeclAccessPair::make(D: FD, AS: AS_none),
2595	Args, CandidateSet&: OCS);
2596	}
2597	switch (OCS.BestViableFunction(S&: *this, Loc: R.getNameLoc(), Best)) {
2598	case OR_Success:
2599	ND = Best->FoundDecl;
2600	Corrected.setCorrectionDecl(ND);
2601	break;
2602	default:
2603	// FIXME: Arbitrarily pick the first declaration for the note.
2604	Corrected.setCorrectionDecl(ND);
2605	break;
2606	}
2607	}
2608	R.addDecl(D: ND);
2609	if (getLangOpts().CPlusPlus && ND->isCXXClassMember()) {
2610	CXXRecordDecl *Record = nullptr;
2611	if (Corrected.getCorrectionSpecifier()) {
2612	const Type *Ty = Corrected.getCorrectionSpecifier()->getAsType();
2613	Record = Ty->getAsCXXRecordDecl();
2614	}
2615	if (!Record)
2616	Record = cast<CXXRecordDecl>(
2617	Val: ND->getDeclContext()->getRedeclContext());
2618	R.setNamingClass(Record);
2619	}
2620
2621	auto *UnderlyingND = ND->getUnderlyingDecl();
2622	AcceptableWithRecovery = isa<ValueDecl>(Val: UnderlyingND) ||
2623	isa<FunctionTemplateDecl>(Val: UnderlyingND);
2624	// FIXME: If we ended up with a typo for a type name or
2625	// Objective-C class name, we're in trouble because the parser
2626	// is in the wrong place to recover. Suggest the typo
2627	// correction, but don't make it a fix-it since we're not going
2628	// to recover well anyway.
2629	AcceptableWithoutRecovery = isa<TypeDecl>(Val: UnderlyingND) ||
2630	getAsTypeTemplateDecl(D: UnderlyingND) ||
2631	isa<ObjCInterfaceDecl>(Val: UnderlyingND);
2632	} else {
2633	// FIXME: We found a keyword. Suggest it, but don't provide a fix-it
2634	// because we aren't able to recover.
2635	AcceptableWithoutRecovery = true;
2636	}
2637
2638	if (AcceptableWithRecovery || AcceptableWithoutRecovery) {
2639	unsigned NoteID = Corrected.getCorrectionDeclAs<ImplicitParamDecl>()
2640	? diag::note_implicit_param_decl
2641	: diag::note_previous_decl;
2642	if (SS.isEmpty())
2643	diagnoseTypo(Correction: Corrected, TypoDiag: PDiag(DiagID: diagnostic_suggest) << Name << NameRange,
2644	PrevNote: PDiag(DiagID: NoteID), ErrorRecovery: AcceptableWithRecovery);
2645	else
2646	diagnoseTypo(Correction: Corrected,
2647	TypoDiag: PDiag(DiagID: diag::err_no_member_suggest)
2648	<< Name << computeDeclContext(SS, EnteringContext: false)
2649	<< DroppedSpecifier << NameRange,
2650	PrevNote: PDiag(DiagID: NoteID), ErrorRecovery: AcceptableWithRecovery);
2651
2652	// Tell the callee whether to try to recover.
2653	return !AcceptableWithRecovery;
2654	}
2655	}
2656	R.clear();
2657
2658	// Emit a special diagnostic for failed member lookups.
2659	// FIXME: computing the declaration context might fail here (?)
2660	if (!SS.isEmpty()) {
2661	Diag(Loc: R.getNameLoc(), DiagID: diag::err_no_member)
2662	<< Name << computeDeclContext(SS, EnteringContext: false) << NameRange;
2663	return true;
2664	}
2665
2666	// Give up, we can't recover.
2667	Diag(Loc: R.getNameLoc(), DiagID: diagnostic) << Name << NameRange;
2668	return true;
2669	}
2670
2671	/// In Microsoft mode, if we are inside a template class whose parent class has
2672	/// dependent base classes, and we can't resolve an unqualified identifier, then
2673	/// assume the identifier is a member of a dependent base class. We can only
2674	/// recover successfully in static methods, instance methods, and other contexts
2675	/// where 'this' is available. This doesn't precisely match MSVC's
2676	/// instantiation model, but it's close enough.
2677	static Expr *
2678	recoverFromMSUnqualifiedLookup(Sema &S, ASTContext &Context,
2679	DeclarationNameInfo &NameInfo,
2680	SourceLocation TemplateKWLoc,
2681	const TemplateArgumentListInfo *TemplateArgs) {
2682	// Only try to recover from lookup into dependent bases in static methods or
2683	// contexts where 'this' is available.
2684	QualType ThisType = S.getCurrentThisType();
2685	const CXXRecordDecl *RD = nullptr;
2686	if (!ThisType.isNull())
2687	RD = ThisType->getPointeeType()->getAsCXXRecordDecl();
2688	else if (auto *MD = dyn_cast<CXXMethodDecl>(Val: S.CurContext))
2689	RD = MD->getParent();
2690	if (!RD || !RD->hasDefinition() || !RD->hasAnyDependentBases())
2691	return nullptr;
2692
2693	// Diagnose this as unqualified lookup into a dependent base class. If 'this'
2694	// is available, suggest inserting 'this->' as a fixit.
2695	SourceLocation Loc = NameInfo.getLoc();
2696	auto DB = S.Diag(Loc, DiagID: diag::ext_undeclared_unqual_id_with_dependent_base);
2697	DB << NameInfo.getName() << RD;
2698
2699	if (!ThisType.isNull()) {
2700	DB << FixItHint::CreateInsertion(InsertionLoc: Loc, Code: "this->");
2701	return CXXDependentScopeMemberExpr::Create(
2702	Ctx: Context, /*This=*/Base: nullptr, BaseType: ThisType, /*IsArrow=*/true,
2703	/*Op=*/OperatorLoc: SourceLocation(), QualifierLoc: NestedNameSpecifierLoc(), TemplateKWLoc,
2704	/*FirstQualifierFoundInScope=*/nullptr, MemberNameInfo: NameInfo, TemplateArgs);
2705	}
2706
2707	// Synthesize a fake NNS that points to the derived class. This will
2708	// perform name lookup during template instantiation.
2709	CXXScopeSpec SS;
2710	auto *NNS =
2711	NestedNameSpecifier::Create(Context, Prefix: nullptr, T: RD->getTypeForDecl());
2712	SS.MakeTrivial(Context, Qualifier: NNS, R: SourceRange(Loc, Loc));
2713	return DependentScopeDeclRefExpr::Create(
2714	Context, QualifierLoc: SS.getWithLocInContext(Context), TemplateKWLoc, NameInfo,
2715	TemplateArgs);
2716	}
2717
2718	ExprResult
2719	Sema::ActOnIdExpression(Scope *S, CXXScopeSpec &SS,
2720	SourceLocation TemplateKWLoc, UnqualifiedId &Id,
2721	bool HasTrailingLParen, bool IsAddressOfOperand,
2722	CorrectionCandidateCallback *CCC,
2723	bool IsInlineAsmIdentifier, Token *KeywordReplacement) {
2724	assert(!(IsAddressOfOperand && HasTrailingLParen) &&
2725	"cannot be direct & operand and have a trailing lparen");
2726	if (SS.isInvalid())
2727	return ExprError();
2728
2729	TemplateArgumentListInfo TemplateArgsBuffer;
2730
2731	// Decompose the UnqualifiedId into the following data.
2732	DeclarationNameInfo NameInfo;
2733	const TemplateArgumentListInfo *TemplateArgs;
2734	DecomposeUnqualifiedId(Id, Buffer&: TemplateArgsBuffer, NameInfo, TemplateArgs);
2735
2736	DeclarationName Name = NameInfo.getName();
2737	IdentifierInfo *II = Name.getAsIdentifierInfo();
2738	SourceLocation NameLoc = NameInfo.getLoc();
2739
2740	if (II && II->isEditorPlaceholder()) {
2741	// FIXME: When typed placeholders are supported we can create a typed
2742	// placeholder expression node.
2743	return ExprError();
2744	}
2745
2746	// This specially handles arguments of attributes appertains to a type of C
2747	// struct field such that the name lookup within a struct finds the member
2748	// name, which is not the case for other contexts in C.
2749	if (isAttrContext() && !getLangOpts().CPlusPlus && S->isClassScope()) {
2750	// See if this is reference to a field of struct.
2751	LookupResult R(*this, NameInfo, LookupMemberName);
2752	// LookupName handles a name lookup from within anonymous struct.
2753	if (LookupName(R, S)) {
2754	if (auto *VD = dyn_cast<ValueDecl>(Val: R.getFoundDecl())) {
2755	QualType type = VD->getType().getNonReferenceType();
2756	// This will eventually be translated into MemberExpr upon
2757	// the use of instantiated struct fields.
2758	return BuildDeclRefExpr(D: VD, Ty: type, VK: VK_LValue, Loc: NameLoc);
2759	}
2760	}
2761	}
2762
2763	// Perform the required lookup.
2764	LookupResult R(*this, NameInfo,
2765	(Id.getKind() == UnqualifiedIdKind::IK_ImplicitSelfParam)
2766	? LookupObjCImplicitSelfParam
2767	: LookupOrdinaryName);
2768	if (TemplateKWLoc.isValid() || TemplateArgs) {
2769	// Lookup the template name again to correctly establish the context in
2770	// which it was found. This is really unfortunate as we already did the
2771	// lookup to determine that it was a template name in the first place. If
2772	// this becomes a performance hit, we can work harder to preserve those
2773	// results until we get here but it's likely not worth it.
2774	AssumedTemplateKind AssumedTemplate;
2775	if (LookupTemplateName(R, S, SS, /*ObjectType=*/QualType(),
2776	/*EnteringContext=*/false, RequiredTemplate: TemplateKWLoc,
2777	ATK: &AssumedTemplate))
2778	return ExprError();
2779
2780	if (R.wasNotFoundInCurrentInstantiation() || SS.isInvalid())
2781	return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
2782	isAddressOfOperand: IsAddressOfOperand, TemplateArgs);
2783	} else {
2784	bool IvarLookupFollowUp = II && !SS.isSet() && getCurMethodDecl();
2785	LookupParsedName(R, S, SS: &SS, /*ObjectType=*/QualType(),
2786	/*AllowBuiltinCreation=*/!IvarLookupFollowUp);
2787
2788	// If the result might be in a dependent base class, this is a dependent
2789	// id-expression.
2790	if (R.wasNotFoundInCurrentInstantiation() || SS.isInvalid())
2791	return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
2792	isAddressOfOperand: IsAddressOfOperand, TemplateArgs);
2793
2794	// If this reference is in an Objective-C method, then we need to do
2795	// some special Objective-C lookup, too.
2796	if (IvarLookupFollowUp) {
2797	ExprResult E(ObjC().LookupInObjCMethod(LookUp&: R, S, II, AllowBuiltinCreation: true));
2798	if (E.isInvalid())
2799	return ExprError();
2800
2801	if (Expr *Ex = E.getAs<Expr>())
2802	return Ex;
2803	}
2804	}
2805
2806	if (R.isAmbiguous())
2807	return ExprError();
2808
2809	// This could be an implicitly declared function reference if the language
2810	// mode allows it as a feature.
2811	if (R.empty() && HasTrailingLParen && II &&
2812	getLangOpts().implicitFunctionsAllowed()) {
2813	NamedDecl *D = ImplicitlyDefineFunction(Loc: NameLoc, II&: *II, S);
2814	if (D) R.addDecl(D);
2815	}
2816
2817	// Determine whether this name might be a candidate for
2818	// argument-dependent lookup.
2819	bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen);
2820
2821	if (R.empty() && !ADL) {
2822	if (SS.isEmpty() && getLangOpts().MSVCCompat) {
2823	if (Expr *E = recoverFromMSUnqualifiedLookup(S&: *this, Context, NameInfo,
2824	TemplateKWLoc, TemplateArgs))
2825	return E;
2826	}
2827
2828	// Don't diagnose an empty lookup for inline assembly.
2829	if (IsInlineAsmIdentifier)
2830	return ExprError();
2831
2832	// If this name wasn't predeclared and if this is not a function
2833	// call, diagnose the problem.
2834	DefaultFilterCCC DefaultValidator(II, SS.isValid() ? SS.getScopeRep()
2835	: nullptr);
2836	DefaultValidator.IsAddressOfOperand = IsAddressOfOperand;
2837	assert((!CCC || CCC->IsAddressOfOperand == IsAddressOfOperand) &&
2838	"Typo correction callback misconfigured");
2839	if (CCC) {
2840	// Make sure the callback knows what the typo being diagnosed is.
2841	CCC->setTypoName(II);
2842	if (SS.isValid())
2843	CCC->setTypoNNS(SS.getScopeRep());
2844	}
2845	// FIXME: DiagnoseEmptyLookup produces bad diagnostics if we're looking for
2846	// a template name, but we happen to have always already looked up the name
2847	// before we get here if it must be a template name.
2848	if (DiagnoseEmptyLookup(S, SS, R, CCC&: CCC ? *CCC : DefaultValidator, ExplicitTemplateArgs: nullptr,
2849	Args: {}, LookupCtx: nullptr))
2850	return ExprError();
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(ObjC().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 (isPotentialImplicitMemberAccess(SS, R, IsAddressOfOperand))
2897	return BuildPossibleImplicitMemberExpr(SS, TemplateKWLoc, R, TemplateArgs,
2898	S);
2899
2900	if (TemplateArgs || TemplateKWLoc.isValid()) {
2901
2902	// In C++1y, if this is a variable template id, then check it
2903	// in BuildTemplateIdExpr().
2904	// The single lookup result must be a variable template declaration.
2905	if (Id.getKind() == UnqualifiedIdKind::IK_TemplateId && Id.TemplateId &&
2906	Id.TemplateId->Kind == TNK_Var_template) {
2907	assert(R.getAsSingle<VarTemplateDecl>() &&
2908	"There should only be one declaration found.");
2909	}
2910
2911	return BuildTemplateIdExpr(SS, TemplateKWLoc, R, RequiresADL: ADL, TemplateArgs);
2912	}
2913
2914	return BuildDeclarationNameExpr(SS, R, NeedsADL: ADL);
2915	}
2916
2917	ExprResult Sema::BuildQualifiedDeclarationNameExpr(
2918	CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo,
2919	bool IsAddressOfOperand, TypeSourceInfo **RecoveryTSI) {
2920	LookupResult R(*this, NameInfo, LookupOrdinaryName);
2921	LookupParsedName(R, /*S=*/nullptr, SS: &SS, /*ObjectType=*/QualType());
2922
2923	if (R.isAmbiguous())
2924	return ExprError();
2925
2926	if (R.wasNotFoundInCurrentInstantiation() || SS.isInvalid())
2927	return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(),
2928	NameInfo, /*TemplateArgs=*/nullptr);
2929
2930	if (R.empty()) {
2931	// Don't diagnose problems with invalid record decl, the secondary no_member
2932	// diagnostic during template instantiation is likely bogus, e.g. if a class
2933	// is invalid because it's derived from an invalid base class, then missing
2934	// members were likely supposed to be inherited.
2935	DeclContext *DC = computeDeclContext(SS);
2936	if (const auto *CD = dyn_cast<CXXRecordDecl>(Val: DC))
2937	if (CD->isInvalidDecl())
2938	return ExprError();
2939	Diag(Loc: NameInfo.getLoc(), DiagID: diag::err_no_member)
2940	<< NameInfo.getName() << DC << SS.getRange();
2941	return ExprError();
2942	}
2943
2944	if (const TypeDecl *TD = R.getAsSingle<TypeDecl>()) {
2945	QualType Ty = Context.getTypeDeclType(Decl: TD);
2946	QualType ET = getElaboratedType(Keyword: ElaboratedTypeKeyword::None, SS, T: Ty);
2947
2948	// Diagnose a missing typename if this resolved unambiguously to a type in
2949	// a dependent context. If we can recover with a type, downgrade this to
2950	// a warning in Microsoft compatibility mode.
2951	unsigned DiagID = diag::err_typename_missing;
2952	if (RecoveryTSI && getLangOpts().MSVCCompat)
2953	DiagID = diag::ext_typename_missing;
2954	SourceLocation Loc = SS.getBeginLoc();
2955	auto D = Diag(Loc, DiagID);
2956	D << ET << SourceRange(Loc, NameInfo.getEndLoc());
2957
2958	// Don't recover if the caller isn't expecting us to or if we're in a SFINAE
2959	// context.
2960	if (!RecoveryTSI)
2961	return ExprError();
2962
2963	// Only issue the fixit if we're prepared to recover.
2964	D << FixItHint::CreateInsertion(InsertionLoc: Loc, Code: "typename ");
2965
2966	// Recover by pretending this was an elaborated type.
2967	TypeLocBuilder TLB;
2968	TLB.pushTypeSpec(T: Ty).setNameLoc(NameInfo.getLoc());
2969
2970	ElaboratedTypeLoc QTL = TLB.push<ElaboratedTypeLoc>(T: ET);
2971	QTL.setElaboratedKeywordLoc(SourceLocation());
2972	QTL.setQualifierLoc(SS.getWithLocInContext(Context));
2973
2974	*RecoveryTSI = TLB.getTypeSourceInfo(Context, T: ET);
2975
2976	return ExprEmpty();
2977	}
2978
2979	// If necessary, build an implicit class member access.
2980	if (isPotentialImplicitMemberAccess(SS, R, IsAddressOfOperand))
2981	return BuildPossibleImplicitMemberExpr(SS,
2982	/*TemplateKWLoc=*/SourceLocation(),
2983	R, /*TemplateArgs=*/nullptr,
2984	/*S=*/nullptr);
2985
2986	return BuildDeclarationNameExpr(SS, R, /*ADL=*/NeedsADL: false);
2987	}
2988
2989	ExprResult
2990	Sema::PerformObjectMemberConversion(Expr *From,
2991	NestedNameSpecifier *Qualifier,
2992	NamedDecl *FoundDecl,
2993	NamedDecl *Member) {
2994	const auto *RD = dyn_cast<CXXRecordDecl>(Val: Member->getDeclContext());
2995	if (!RD)
2996	return From;
2997
2998	QualType DestRecordType;
2999	QualType DestType;
3000	QualType FromRecordType;
3001	QualType FromType = From->getType();
3002	bool PointerConversions = false;
3003	if (isa<FieldDecl>(Val: Member)) {
3004	DestRecordType = Context.getCanonicalType(T: Context.getTypeDeclType(Decl: RD));
3005	auto FromPtrType = FromType->getAs<PointerType>();
3006	DestRecordType = Context.getAddrSpaceQualType(
3007	T: DestRecordType, AddressSpace: FromPtrType
3008	? FromType->getPointeeType().getAddressSpace()
3009	: FromType.getAddressSpace());
3010
3011	if (FromPtrType) {
3012	DestType = Context.getPointerType(T: DestRecordType);
3013	FromRecordType = FromPtrType->getPointeeType();
3014	PointerConversions = true;
3015	} else {
3016	DestType = DestRecordType;
3017	FromRecordType = FromType;
3018	}
3019	} else if (const auto *Method = dyn_cast<CXXMethodDecl>(Val: Member)) {
3020	if (!Method->isImplicitObjectMemberFunction())
3021	return From;
3022
3023	DestType = Method->getThisType().getNonReferenceType();
3024	DestRecordType = Method->getFunctionObjectParameterType();
3025
3026	if (FromType->getAs<PointerType>()) {
3027	FromRecordType = FromType->getPointeeType();
3028	PointerConversions = true;
3029	} else {
3030	FromRecordType = FromType;
3031	DestType = DestRecordType;
3032	}
3033
3034	LangAS FromAS = FromRecordType.getAddressSpace();
3035	LangAS DestAS = DestRecordType.getAddressSpace();
3036	if (FromAS != DestAS) {
3037	QualType FromRecordTypeWithoutAS =
3038	Context.removeAddrSpaceQualType(T: FromRecordType);
3039	QualType FromTypeWithDestAS =
3040	Context.getAddrSpaceQualType(T: FromRecordTypeWithoutAS, AddressSpace: DestAS);
3041	if (PointerConversions)
3042	FromTypeWithDestAS = Context.getPointerType(T: FromTypeWithDestAS);
3043	From = ImpCastExprToType(E: From, Type: FromTypeWithDestAS,
3044	CK: CK_AddressSpaceConversion, VK: From->getValueKind())
3045	.get();
3046	}
3047	} else {
3048	// No conversion necessary.
3049	return From;
3050	}
3051
3052	if (DestType->isDependentType() || FromType->isDependentType())
3053	return From;
3054
3055	// If the unqualified types are the same, no conversion is necessary.
3056	if (Context.hasSameUnqualifiedType(T1: FromRecordType, T2: DestRecordType))
3057	return From;
3058
3059	SourceRange FromRange = From->getSourceRange();
3060	SourceLocation FromLoc = FromRange.getBegin();
3061
3062	ExprValueKind VK = From->getValueKind();
3063
3064	// C++ [class.member.lookup]p8:
3065	// [...] Ambiguities can often be resolved by qualifying a name with its
3066	// class name.
3067	//
3068	// If the member was a qualified name and the qualified referred to a
3069	// specific base subobject type, we'll cast to that intermediate type
3070	// first and then to the object in which the member is declared. That allows
3071	// one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as:
3072	//
3073	// class Base { public: int x; };
3074	// class Derived1 : public Base { };
3075	// class Derived2 : public Base { };
3076	// class VeryDerived : public Derived1, public Derived2 { void f(); };
3077	//
3078	// void VeryDerived::f() {
3079	// x = 17; // error: ambiguous base subobjects
3080	// Derived1::x = 17; // okay, pick the Base subobject of Derived1
3081	// }
3082	if (Qualifier && Qualifier->getAsType()) {
3083	QualType QType = QualType(Qualifier->getAsType(), 0);
3084	assert(QType->isRecordType() && "lookup done with non-record type");
3085
3086	QualType QRecordType = QualType(QType->castAs<RecordType>(), 0);
3087
3088	// In C++98, the qualifier type doesn't actually have to be a base
3089	// type of the object type, in which case we just ignore it.
3090	// Otherwise build the appropriate casts.
3091	if (IsDerivedFrom(Loc: FromLoc, Derived: FromRecordType, Base: QRecordType)) {
3092	CXXCastPath BasePath;
3093	if (CheckDerivedToBaseConversion(Derived: FromRecordType, Base: QRecordType,
3094	Loc: FromLoc, Range: FromRange, BasePath: &BasePath))
3095	return ExprError();
3096
3097	if (PointerConversions)
3098	QType = Context.getPointerType(T: QType);
3099	From = ImpCastExprToType(E: From, Type: QType, CK: CK_UncheckedDerivedToBase,
3100	VK, BasePath: &BasePath).get();
3101
3102	FromType = QType;
3103	FromRecordType = QRecordType;
3104
3105	// If the qualifier type was the same as the destination type,
3106	// we're done.
3107	if (Context.hasSameUnqualifiedType(T1: FromRecordType, T2: DestRecordType))
3108	return From;
3109	}
3110	}
3111
3112	CXXCastPath BasePath;
3113	if (CheckDerivedToBaseConversion(Derived: FromRecordType, Base: DestRecordType,
3114	Loc: FromLoc, Range: FromRange, BasePath: &BasePath,
3115	/*IgnoreAccess=*/true))
3116	return ExprError();
3117
3118	// Propagate qualifiers to base subobjects as per:
3119	// C++ [basic.type.qualifier]p1.2:
3120	// A volatile object is [...] a subobject of a volatile object.
3121	Qualifiers FromTypeQuals = FromType.getQualifiers();
3122	FromTypeQuals.setAddressSpace(DestType.getAddressSpace());
3123	DestType = Context.getQualifiedType(T: DestType, Qs: FromTypeQuals);
3124
3125	return ImpCastExprToType(E: From, Type: DestType, CK: CK_UncheckedDerivedToBase, VK,
3126	BasePath: &BasePath);
3127	}
3128
3129	bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS,
3130	const LookupResult &R,
3131	bool HasTrailingLParen) {
3132	// Only when used directly as the postfix-expression of a call.
3133	if (!HasTrailingLParen)
3134	return false;
3135
3136	// Never if a scope specifier was provided.
3137	if (SS.isNotEmpty())
3138	return false;
3139
3140	// Only in C++ or ObjC++.
3141	if (!getLangOpts().CPlusPlus)
3142	return false;
3143
3144	// Turn off ADL when we find certain kinds of declarations during
3145	// normal lookup:
3146	for (const NamedDecl *D : R) {
3147	// C++0x [basic.lookup.argdep]p3:
3148	// -- a declaration of a class member
3149	// Since using decls preserve this property, we check this on the
3150	// original decl.
3151	if (D->isCXXClassMember())
3152	return false;
3153
3154	// C++0x [basic.lookup.argdep]p3:
3155	// -- a block-scope function declaration that is not a
3156	// using-declaration
3157	// NOTE: we also trigger this for function templates (in fact, we
3158	// don't check the decl type at all, since all other decl types
3159	// turn off ADL anyway).
3160	if (isa<UsingShadowDecl>(Val: D))
3161	D = cast<UsingShadowDecl>(Val: D)->getTargetDecl();
3162	else if (D->getLexicalDeclContext()->isFunctionOrMethod())
3163	return false;
3164
3165	// C++0x [basic.lookup.argdep]p3:
3166	// -- a declaration that is neither a function or a function
3167	// template
3168	// And also for builtin functions.
3169	if (const auto *FDecl = dyn_cast<FunctionDecl>(Val: D)) {
3170	// But also builtin functions.
3171	if (FDecl->getBuiltinID() && FDecl->isImplicit())
3172	return false;
3173	} else if (!isa<FunctionTemplateDecl>(Val: D))
3174	return false;
3175	}
3176
3177	return true;
3178	}
3179
3180
3181	/// Diagnoses obvious problems with the use of the given declaration
3182	/// as an expression. This is only actually called for lookups that
3183	/// were not overloaded, and it doesn't promise that the declaration
3184	/// will in fact be used.
3185	static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D,
3186	bool AcceptInvalid) {
3187	if (D->isInvalidDecl() && !AcceptInvalid)
3188	return true;
3189
3190	if (isa<TypedefNameDecl>(Val: D)) {
3191	S.Diag(Loc, DiagID: diag::err_unexpected_typedef) << D->getDeclName();
3192	return true;
3193	}
3194
3195	if (isa<ObjCInterfaceDecl>(Val: D)) {
3196	S.Diag(Loc, DiagID: diag::err_unexpected_interface) << D->getDeclName();
3197	return true;
3198	}
3199
3200	if (isa<NamespaceDecl>(Val: D)) {
3201	S.Diag(Loc, DiagID: diag::err_unexpected_namespace) << D->getDeclName();
3202	return true;
3203	}
3204
3205	return false;
3206	}
3207
3208	// Certain multiversion types should be treated as overloaded even when there is
3209	// only one result.
3210	static bool ShouldLookupResultBeMultiVersionOverload(const LookupResult &R) {
3211	assert(R.isSingleResult() && "Expected only a single result");
3212	const auto *FD = dyn_cast<FunctionDecl>(Val: R.getFoundDecl());
3213	return FD &&
3214	(FD->isCPUDispatchMultiVersion() || FD->isCPUSpecificMultiVersion());
3215	}
3216
3217	ExprResult Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS,
3218	LookupResult &R, bool NeedsADL,
3219	bool AcceptInvalidDecl) {
3220	// If this is a single, fully-resolved result and we don't need ADL,
3221	// just build an ordinary singleton decl ref.
3222	if (!NeedsADL && R.isSingleResult() &&
3223	!R.getAsSingle<FunctionTemplateDecl>() &&
3224	!ShouldLookupResultBeMultiVersionOverload(R))
3225	return BuildDeclarationNameExpr(SS, NameInfo: R.getLookupNameInfo(), D: R.getFoundDecl(),
3226	FoundD: R.getRepresentativeDecl(), TemplateArgs: nullptr,
3227	AcceptInvalidDecl);
3228
3229	// We only need to check the declaration if there's exactly one
3230	// result, because in the overloaded case the results can only be
3231	// functions and function templates.
3232	if (R.isSingleResult() && !ShouldLookupResultBeMultiVersionOverload(R) &&
3233	CheckDeclInExpr(S&: *this, Loc: R.getNameLoc(), D: R.getFoundDecl(),
3234	AcceptInvalid: AcceptInvalidDecl))
3235	return ExprError();
3236
3237	// Otherwise, just build an unresolved lookup expression. Suppress
3238	// any lookup-related diagnostics; we'll hash these out later, when
3239	// we've picked a target.
3240	R.suppressDiagnostics();
3241
3242	UnresolvedLookupExpr *ULE = UnresolvedLookupExpr::Create(
3243	Context, NamingClass: R.getNamingClass(), QualifierLoc: SS.getWithLocInContext(Context),
3244	NameInfo: R.getLookupNameInfo(), RequiresADL: NeedsADL, Begin: R.begin(), End: R.end(),
3245	/*KnownDependent=*/false, /*KnownInstantiationDependent=*/false);
3246
3247	return ULE;
3248	}
3249
3250	static void diagnoseUncapturableValueReferenceOrBinding(Sema &S,
3251	SourceLocation loc,
3252	ValueDecl *var);
3253
3254	ExprResult Sema::BuildDeclarationNameExpr(
3255	const CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo, NamedDecl *D,
3256	NamedDecl *FoundD, const TemplateArgumentListInfo *TemplateArgs,
3257	bool AcceptInvalidDecl) {
3258	assert(D && "Cannot refer to a NULL declaration");
3259	assert(!isa<FunctionTemplateDecl>(D) &&
3260	"Cannot refer unambiguously to a function template");
3261
3262	SourceLocation Loc = NameInfo.getLoc();
3263	if (CheckDeclInExpr(S&: *this, Loc, D, AcceptInvalid: AcceptInvalidDecl)) {
3264	// Recovery from invalid cases (e.g. D is an invalid Decl).
3265	// We use the dependent type for the RecoveryExpr to prevent bogus follow-up
3266	// diagnostics, as invalid decls use int as a fallback type.
3267	return CreateRecoveryExpr(Begin: NameInfo.getBeginLoc(), End: NameInfo.getEndLoc(), SubExprs: {});
3268	}
3269
3270	if (TemplateDecl *TD = dyn_cast<TemplateDecl>(Val: D)) {
3271	// Specifically diagnose references to class templates that are missing
3272	// a template argument list.
3273	diagnoseMissingTemplateArguments(SS, /*TemplateKeyword=*/false, TD, Loc);
3274	return ExprError();
3275	}
3276
3277	// Make sure that we're referring to a value.
3278	if (!isa<ValueDecl, UnresolvedUsingIfExistsDecl>(Val: D)) {
3279	Diag(Loc, DiagID: diag::err_ref_non_value) << D << SS.getRange();
3280	Diag(Loc: D->getLocation(), DiagID: diag::note_declared_at);
3281	return ExprError();
3282	}
3283
3284	// Check whether this declaration can be used. Note that we suppress
3285	// this check when we're going to perform argument-dependent lookup
3286	// on this function name, because this might not be the function
3287	// that overload resolution actually selects.
3288	if (DiagnoseUseOfDecl(D, Locs: Loc))
3289	return ExprError();
3290
3291	auto *VD = cast<ValueDecl>(Val: D);
3292
3293	// Only create DeclRefExpr's for valid Decl's.
3294	if (VD->isInvalidDecl() && !AcceptInvalidDecl)
3295	return ExprError();
3296
3297	// Handle members of anonymous structs and unions. If we got here,
3298	// and the reference is to a class member indirect field, then this
3299	// must be the subject of a pointer-to-member expression.
3300	if (auto *IndirectField = dyn_cast<IndirectFieldDecl>(Val: VD);
3301	IndirectField && !IndirectField->isCXXClassMember())
3302	return BuildAnonymousStructUnionMemberReference(SS, nameLoc: NameInfo.getLoc(),
3303	indirectField: IndirectField);
3304
3305	QualType type = VD->getType();
3306	if (type.isNull())
3307	return ExprError();
3308	ExprValueKind valueKind = VK_PRValue;
3309
3310	// In 'T ...V;', the type of the declaration 'V' is 'T...', but the type of
3311	// a reference to 'V' is simply (unexpanded) 'T'. The type, like the value,
3312	// is expanded by some outer '...' in the context of the use.
3313	type = type.getNonPackExpansionType();
3314
3315	switch (D->getKind()) {
3316	// Ignore all the non-ValueDecl kinds.
3317	#define ABSTRACT_DECL(kind)
3318	#define VALUE(type, base)
3319	#define DECL(type, base) case Decl::type:
3320	#include "clang/AST/DeclNodes.inc"
3321	llvm_unreachable("invalid value decl kind");
3322
3323	// These shouldn't make it here.
3324	case Decl::ObjCAtDefsField:
3325	llvm_unreachable("forming non-member reference to ivar?");
3326
3327	// Enum constants are always r-values and never references.
3328	// Unresolved using declarations are dependent.
3329	case Decl::EnumConstant:
3330	case Decl::UnresolvedUsingValue:
3331	case Decl::OMPDeclareReduction:
3332	case Decl::OMPDeclareMapper:
3333	valueKind = VK_PRValue;
3334	break;
3335
3336	// Fields and indirect fields that got here must be for
3337	// pointer-to-member expressions; we just call them l-values for
3338	// internal consistency, because this subexpression doesn't really
3339	// exist in the high-level semantics.
3340	case Decl::Field:
3341	case Decl::IndirectField:
3342	case Decl::ObjCIvar:
3343	assert((getLangOpts().CPlusPlus || isAttrContext()) &&
3344	"building reference to field in C?");
3345
3346	// These can't have reference type in well-formed programs, but
3347	// for internal consistency we do this anyway.
3348	type = type.getNonReferenceType();
3349	valueKind = VK_LValue;
3350	break;
3351
3352	// Non-type template parameters are either l-values or r-values
3353	// depending on the type.
3354	case Decl::NonTypeTemplateParm: {
3355	if (const ReferenceType *reftype = type->getAs<ReferenceType>()) {
3356	type = reftype->getPointeeType();
3357	valueKind = VK_LValue; // even if the parameter is an r-value reference
3358	break;
3359	}
3360
3361	// [expr.prim.id.unqual]p2:
3362	// If the entity is a template parameter object for a template
3363	// parameter of type T, the type of the expression is const T.
3364	// [...] The expression is an lvalue if the entity is a [...] template
3365	// parameter object.
3366	if (type->isRecordType()) {
3367	type = type.getUnqualifiedType().withConst();
3368	valueKind = VK_LValue;
3369	break;
3370	}
3371
3372	// For non-references, we need to strip qualifiers just in case
3373	// the template parameter was declared as 'const int' or whatever.
3374	valueKind = VK_PRValue;
3375	type = type.getUnqualifiedType();
3376	break;
3377	}
3378
3379	case Decl::Var:
3380	case Decl::VarTemplateSpecialization:
3381	case Decl::VarTemplatePartialSpecialization:
3382	case Decl::Decomposition:
3383	case Decl::Binding:
3384	case Decl::OMPCapturedExpr:
3385	// In C, "extern void blah;" is valid and is an r-value.
3386	if (!getLangOpts().CPlusPlus && !type.hasQualifiers() &&
3387	type->isVoidType()) {
3388	valueKind = VK_PRValue;
3389	break;
3390	}
3391	[[fallthrough]];
3392
3393	case Decl::ImplicitParam:
3394	case Decl::ParmVar: {
3395	// These are always l-values.
3396	valueKind = VK_LValue;
3397	type = type.getNonReferenceType();
3398
3399	// FIXME: Does the addition of const really only apply in
3400	// potentially-evaluated contexts? Since the variable isn't actually
3401	// captured in an unevaluated context, it seems that the answer is no.
3402	if (!isUnevaluatedContext()) {
3403	QualType CapturedType = getCapturedDeclRefType(Var: cast<ValueDecl>(Val: VD), Loc);
3404	if (!CapturedType.isNull())
3405	type = CapturedType;
3406	}
3407	break;
3408	}
3409
3410	case Decl::Function: {
3411	if (unsigned BID = cast<FunctionDecl>(Val: VD)->getBuiltinID()) {
3412	if (!Context.BuiltinInfo.isDirectlyAddressable(ID: BID)) {
3413	type = Context.BuiltinFnTy;
3414	valueKind = VK_PRValue;
3415	break;
3416	}
3417	}
3418
3419	const FunctionType *fty = type->castAs<FunctionType>();
3420
3421	// If we're referring to a function with an __unknown_anytype
3422	// result type, make the entire expression __unknown_anytype.
3423	if (fty->getReturnType() == Context.UnknownAnyTy) {
3424	type = Context.UnknownAnyTy;
3425	valueKind = VK_PRValue;
3426	break;
3427	}
3428
3429	// Functions are l-values in C++.
3430	if (getLangOpts().CPlusPlus) {
3431	valueKind = VK_LValue;
3432	break;
3433	}
3434
3435	// C99 DR 316 says that, if a function type comes from a
3436	// function definition (without a prototype), that type is only
3437	// used for checking compatibility. Therefore, when referencing
3438	// the function, we pretend that we don't have the full function
3439	// type.
3440	if (!cast<FunctionDecl>(Val: VD)->hasPrototype() && isa<FunctionProtoType>(Val: fty))
3441	type = Context.getFunctionNoProtoType(ResultTy: fty->getReturnType(),
3442	Info: fty->getExtInfo());
3443
3444	// Functions are r-values in C.
3445	valueKind = VK_PRValue;
3446	break;
3447	}
3448
3449	case Decl::CXXDeductionGuide:
3450	llvm_unreachable("building reference to deduction guide");
3451
3452	case Decl::MSProperty:
3453	case Decl::MSGuid:
3454	case Decl::TemplateParamObject:
3455	// FIXME: Should MSGuidDecl and template parameter objects be subject to
3456	// capture in OpenMP, or duplicated between host and device?
3457	valueKind = VK_LValue;
3458	break;
3459
3460	case Decl::UnnamedGlobalConstant:
3461	valueKind = VK_LValue;
3462	break;
3463
3464	case Decl::CXXMethod:
3465	// If we're referring to a method with an __unknown_anytype
3466	// result type, make the entire expression __unknown_anytype.
3467	// This should only be possible with a type written directly.
3468	if (const FunctionProtoType *proto =
3469	dyn_cast<FunctionProtoType>(Val: VD->getType()))
3470	if (proto->getReturnType() == Context.UnknownAnyTy) {
3471	type = Context.UnknownAnyTy;
3472	valueKind = VK_PRValue;
3473	break;
3474	}
3475
3476	// C++ methods are l-values if static, r-values if non-static.
3477	if (cast<CXXMethodDecl>(Val: VD)->isStatic()) {
3478	valueKind = VK_LValue;
3479	break;
3480	}
3481	[[fallthrough]];
3482
3483	case Decl::CXXConversion:
3484	case Decl::CXXDestructor:
3485	case Decl::CXXConstructor:
3486	valueKind = VK_PRValue;
3487	break;
3488	}
3489
3490	auto *E =
3491	BuildDeclRefExpr(D: VD, Ty: type, VK: valueKind, NameInfo, SS: &SS, FoundD,
3492	/*FIXME: TemplateKWLoc*/ TemplateKWLoc: SourceLocation(), TemplateArgs);
3493	// Clang AST consumers assume a DeclRefExpr refers to a valid decl. We
3494	// wrap a DeclRefExpr referring to an invalid decl with a dependent-type
3495	// RecoveryExpr to avoid follow-up semantic analysis (thus prevent bogus
3496	// diagnostics).
3497	if (VD->isInvalidDecl() && E)
3498	return CreateRecoveryExpr(Begin: E->getBeginLoc(), End: E->getEndLoc(), SubExprs: {E});
3499	return E;
3500	}
3501
3502	static void ConvertUTF8ToWideString(unsigned CharByteWidth, StringRef Source,
3503	SmallString<32> &Target) {
3504	Target.resize(N: CharByteWidth * (Source.size() + 1));
3505	char *ResultPtr = &Target[0];
3506	const llvm::UTF8 *ErrorPtr;
3507	bool success =
3508	llvm::ConvertUTF8toWide(WideCharWidth: CharByteWidth, Source, ResultPtr, ErrorPtr);
3509	(void)success;
3510	assert(success);
3511	Target.resize(N: ResultPtr - &Target[0]);
3512	}
3513
3514	ExprResult Sema::BuildPredefinedExpr(SourceLocation Loc,
3515	PredefinedIdentKind IK) {
3516	Decl *currentDecl = getPredefinedExprDecl(DC: CurContext);
3517	if (!currentDecl) {
3518	Diag(Loc, DiagID: diag::ext_predef_outside_function);
3519	currentDecl = Context.getTranslationUnitDecl();
3520	}
3521
3522	QualType ResTy;
3523	StringLiteral *SL = nullptr;
3524	if (cast<DeclContext>(Val: currentDecl)->isDependentContext())
3525	ResTy = Context.DependentTy;
3526	else {
3527	// Pre-defined identifiers are of type char[x], where x is the length of
3528	// the string.
3529	bool ForceElaboratedPrinting =
3530	IK == PredefinedIdentKind::Function && getLangOpts().MSVCCompat;
3531	auto Str =
3532	PredefinedExpr::ComputeName(IK, CurrentDecl: currentDecl, ForceElaboratedPrinting);
3533	unsigned Length = Str.length();
3534
3535	llvm::APInt LengthI(32, Length + 1);
3536	if (IK == PredefinedIdentKind::LFunction ||
3537	IK == PredefinedIdentKind::LFuncSig) {
3538	ResTy =
3539	Context.adjustStringLiteralBaseType(StrLTy: Context.WideCharTy.withConst());
3540	SmallString<32> RawChars;
3541	ConvertUTF8ToWideString(CharByteWidth: Context.getTypeSizeInChars(T: ResTy).getQuantity(),
3542	Source: Str, Target&: RawChars);
3543	ResTy = Context.getConstantArrayType(EltTy: ResTy, ArySize: LengthI, SizeExpr: nullptr,
3544	ASM: ArraySizeModifier::Normal,
3545	/*IndexTypeQuals*/ 0);
3546	SL = StringLiteral::Create(Ctx: Context, Str: RawChars, Kind: StringLiteralKind::Wide,
3547	/*Pascal*/ false, Ty: ResTy, Locs: Loc);
3548	} else {
3549	ResTy = Context.adjustStringLiteralBaseType(StrLTy: Context.CharTy.withConst());
3550	ResTy = Context.getConstantArrayType(EltTy: ResTy, ArySize: LengthI, SizeExpr: nullptr,
3551	ASM: ArraySizeModifier::Normal,
3552	/*IndexTypeQuals*/ 0);
3553	SL = StringLiteral::Create(Ctx: Context, Str, Kind: StringLiteralKind::Ordinary,
3554	/*Pascal*/ false, Ty: ResTy, Locs: Loc);
3555	}
3556	}
3557
3558	return PredefinedExpr::Create(Ctx: Context, L: Loc, FNTy: ResTy, IK, IsTransparent: LangOpts.MicrosoftExt,
3559	SL);
3560	}
3561
3562	ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) {
3563	return BuildPredefinedExpr(Loc, IK: getPredefinedExprKind(Kind));
3564	}
3565
3566	ExprResult Sema::ActOnCharacterConstant(const Token &Tok, Scope *UDLScope) {
3567	SmallString<16> CharBuffer;
3568	bool Invalid = false;
3569	StringRef ThisTok = PP.getSpelling(Tok, Buffer&: CharBuffer, Invalid: &Invalid);
3570	if (Invalid)
3571	return ExprError();
3572
3573	CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(),
3574	PP, Tok.getKind());
3575	if (Literal.hadError())
3576	return ExprError();
3577
3578	QualType Ty;
3579	if (Literal.isWide())
3580	Ty = Context.WideCharTy; // L'x' -> wchar_t in C and C++.
3581	else if (Literal.isUTF8() && getLangOpts().C23)
3582	Ty = Context.UnsignedCharTy; // u8'x' -> unsigned char in C23
3583	else if (Literal.isUTF8() && getLangOpts().Char8)
3584	Ty = Context.Char8Ty; // u8'x' -> char8_t when it exists.
3585	else if (Literal.isUTF16())
3586	Ty = Context.Char16Ty; // u'x' -> char16_t in C11 and C++11.
3587	else if (Literal.isUTF32())
3588	Ty = Context.Char32Ty; // U'x' -> char32_t in C11 and C++11.
3589	else if (!getLangOpts().CPlusPlus || Literal.isMultiChar())
3590	Ty = Context.IntTy; // 'x' -> int in C, 'wxyz' -> int in C++.
3591	else
3592	Ty = Context.CharTy; // 'x' -> char in C++;
3593	// u8'x' -> char in C11-C17 and in C++ without char8_t.
3594
3595	CharacterLiteralKind Kind = CharacterLiteralKind::Ascii;
3596	if (Literal.isWide())
3597	Kind = CharacterLiteralKind::Wide;
3598	else if (Literal.isUTF16())
3599	Kind = CharacterLiteralKind::UTF16;
3600	else if (Literal.isUTF32())
3601	Kind = CharacterLiteralKind::UTF32;
3602	else if (Literal.isUTF8())
3603	Kind = CharacterLiteralKind::UTF8;
3604
3605	Expr *Lit = new (Context) CharacterLiteral(Literal.getValue(), Kind, Ty,
3606	Tok.getLocation());
3607
3608	if (Literal.getUDSuffix().empty())
3609	return Lit;
3610
3611	// We're building a user-defined literal.
3612	IdentifierInfo *UDSuffix = &Context.Idents.get(Name: Literal.getUDSuffix());
3613	SourceLocation UDSuffixLoc =
3614	getUDSuffixLoc(S&: *this, TokLoc: Tok.getLocation(), Offset: Literal.getUDSuffixOffset());
3615
3616	// Make sure we're allowed user-defined literals here.
3617	if (!UDLScope)
3618	return ExprError(Diag(Loc: UDSuffixLoc, DiagID: diag::err_invalid_character_udl));
3619
3620	// C++11 [lex.ext]p6: The literal L is treated as a call of the form
3621	// operator "" X (ch)
3622	return BuildCookedLiteralOperatorCall(S&: *this, Scope: UDLScope, UDSuffix, UDSuffixLoc,
3623	Args: Lit, LitEndLoc: Tok.getLocation());
3624	}
3625
3626	ExprResult Sema::ActOnIntegerConstant(SourceLocation Loc, int64_t Val) {
3627	unsigned IntSize = Context.getTargetInfo().getIntWidth();
3628	return IntegerLiteral::Create(C: Context,
3629	V: llvm::APInt(IntSize, Val, /*isSigned=*/true),
3630	type: Context.IntTy, l: Loc);
3631	}
3632
3633	static Expr *BuildFloatingLiteral(Sema &S, NumericLiteralParser &Literal,
3634	QualType Ty, SourceLocation Loc) {
3635	const llvm::fltSemantics &Format = S.Context.getFloatTypeSemantics(T: Ty);
3636
3637	using llvm::APFloat;
3638	APFloat Val(Format);
3639
3640	llvm::RoundingMode RM = S.CurFPFeatures.getRoundingMode();
3641	if (RM == llvm::RoundingMode::Dynamic)
3642	RM = llvm::RoundingMode::NearestTiesToEven;
3643	APFloat::opStatus result = Literal.GetFloatValue(Result&: Val, RM);
3644
3645	// Overflow is always an error, but underflow is only an error if
3646	// we underflowed to zero (APFloat reports denormals as underflow).
3647	if ((result & APFloat::opOverflow) ||
3648	((result & APFloat::opUnderflow) && Val.isZero())) {
3649	unsigned diagnostic;
3650	SmallString<20> buffer;
3651	if (result & APFloat::opOverflow) {
3652	diagnostic = diag::warn_float_overflow;
3653	APFloat::getLargest(Sem: Format).toString(Str&: buffer);
3654	} else {
3655	diagnostic = diag::warn_float_underflow;
3656	APFloat::getSmallest(Sem: Format).toString(Str&: buffer);
3657	}
3658
3659	S.Diag(Loc, DiagID: diagnostic) << Ty << buffer.str();
3660	}
3661
3662	bool isExact = (result == APFloat::opOK);
3663	return FloatingLiteral::Create(C: S.Context, V: Val, isexact: isExact, Type: Ty, L: Loc);
3664	}
3665
3666	bool Sema::CheckLoopHintExpr(Expr *E, SourceLocation Loc, bool AllowZero) {
3667	assert(E && "Invalid expression");
3668
3669	if (E->isValueDependent())
3670	return false;
3671
3672	QualType QT = E->getType();
3673	if (!QT->isIntegerType() || QT->isBooleanType() || QT->isCharType()) {
3674	Diag(Loc: E->getExprLoc(), DiagID: diag::err_pragma_loop_invalid_argument_type) << QT;
3675	return true;
3676	}
3677
3678	llvm::APSInt ValueAPS;
3679	ExprResult R = VerifyIntegerConstantExpression(E, Result: &ValueAPS);
3680
3681	if (R.isInvalid())
3682	return true;
3683
3684	// GCC allows the value of unroll count to be 0.
3685	// https://gcc.gnu.org/onlinedocs/gcc/Loop-Specific-Pragmas.html says
3686	// "The values of 0 and 1 block any unrolling of the loop."
3687	// The values doesn't have to be strictly positive in '#pragma GCC unroll' and
3688	// '#pragma unroll' cases.
3689	bool ValueIsPositive =
3690	AllowZero ? ValueAPS.isNonNegative() : ValueAPS.isStrictlyPositive();
3691	if (!ValueIsPositive || ValueAPS.getActiveBits() > 31) {
3692	Diag(Loc: E->getExprLoc(), DiagID: diag::err_requires_positive_value)
3693	<< toString(I: ValueAPS, Radix: 10) << ValueIsPositive;
3694	return true;
3695	}
3696
3697	return false;
3698	}
3699
3700	ExprResult Sema::ActOnNumericConstant(const Token &Tok, Scope *UDLScope) {
3701	// Fast path for a single digit (which is quite common). A single digit
3702	// cannot have a trigraph, escaped newline, radix prefix, or suffix.
3703	if (Tok.getLength() == 1 || Tok.getKind() == tok::binary_data) {
3704	const uint8_t Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok);
3705	return ActOnIntegerConstant(Loc: Tok.getLocation(), Val);
3706	}
3707
3708	SmallString<128> SpellingBuffer;
3709	// NumericLiteralParser wants to overread by one character. Add padding to
3710	// the buffer in case the token is copied to the buffer. If getSpelling()
3711	// returns a StringRef to the memory buffer, it should have a null char at
3712	// the EOF, so it is also safe.
3713	SpellingBuffer.resize(N: Tok.getLength() + 1);
3714
3715	// Get the spelling of the token, which eliminates trigraphs, etc.
3716	bool Invalid = false;
3717	StringRef TokSpelling = PP.getSpelling(Tok, Buffer&: SpellingBuffer, Invalid: &Invalid);
3718	if (Invalid)
3719	return ExprError();
3720
3721	NumericLiteralParser Literal(TokSpelling, Tok.getLocation(),
3722	PP.getSourceManager(), PP.getLangOpts(),
3723	PP.getTargetInfo(), PP.getDiagnostics());
3724	if (Literal.hadError)
3725	return ExprError();
3726
3727	if (Literal.hasUDSuffix()) {
3728	// We're building a user-defined literal.
3729	const IdentifierInfo *UDSuffix = &Context.Idents.get(Name: Literal.getUDSuffix());
3730	SourceLocation UDSuffixLoc =
3731	getUDSuffixLoc(S&: *this, TokLoc: Tok.getLocation(), Offset: Literal.getUDSuffixOffset());
3732
3733	// Make sure we're allowed user-defined literals here.
3734	if (!UDLScope)
3735	return ExprError(Diag(Loc: UDSuffixLoc, DiagID: diag::err_invalid_numeric_udl));
3736
3737	QualType CookedTy;
3738	if (Literal.isFloatingLiteral()) {
3739	// C++11 [lex.ext]p4: If S contains a literal operator with parameter type
3740	// long double, the literal is treated as a call of the form
3741	// operator "" X (f L)
3742	CookedTy = Context.LongDoubleTy;
3743	} else {
3744	// C++11 [lex.ext]p3: If S contains a literal operator with parameter type
3745	// unsigned long long, the literal is treated as a call of the form
3746	// operator "" X (n ULL)
3747	CookedTy = Context.UnsignedLongLongTy;
3748	}
3749
3750	DeclarationName OpName =
3751	Context.DeclarationNames.getCXXLiteralOperatorName(II: UDSuffix);
3752	DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
3753	OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
3754
3755	SourceLocation TokLoc = Tok.getLocation();
3756
3757	// Perform literal operator lookup to determine if we're building a raw
3758	// literal or a cooked one.
3759	LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName);
3760	switch (LookupLiteralOperator(S: UDLScope, R, ArgTys: CookedTy,
3761	/*AllowRaw*/ true, /*AllowTemplate*/ true,
3762	/*AllowStringTemplatePack*/ AllowStringTemplate: false,
3763	/*DiagnoseMissing*/ !Literal.isImaginary)) {
3764	case LOLR_ErrorNoDiagnostic:
3765	// Lookup failure for imaginary constants isn't fatal, there's still the
3766	// GNU extension producing _Complex types.
3767	break;
3768	case LOLR_Error:
3769	return ExprError();
3770	case LOLR_Cooked: {
3771	Expr *Lit;
3772	if (Literal.isFloatingLiteral()) {
3773	Lit = BuildFloatingLiteral(S&: *this, Literal, Ty: CookedTy, Loc: Tok.getLocation());
3774	} else {
3775	llvm::APInt ResultVal(Context.getTargetInfo().getLongLongWidth(), 0);
3776	if (Literal.GetIntegerValue(Val&: ResultVal))
3777	Diag(Loc: Tok.getLocation(), DiagID: diag::err_integer_literal_too_large)
3778	<< /* Unsigned */ 1;
3779	Lit = IntegerLiteral::Create(C: Context, V: ResultVal, type: CookedTy,
3780	l: Tok.getLocation());
3781	}
3782	return BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args: Lit, LitEndLoc: TokLoc);
3783	}
3784
3785	case LOLR_Raw: {
3786	// C++11 [lit.ext]p3, p4: If S contains a raw literal operator, the
3787	// literal is treated as a call of the form
3788	// operator "" X ("n")
3789	unsigned Length = Literal.getUDSuffixOffset();
3790	QualType StrTy = Context.getConstantArrayType(
3791	EltTy: Context.adjustStringLiteralBaseType(StrLTy: Context.CharTy.withConst()),
3792	ArySize: llvm::APInt(32, Length + 1), SizeExpr: nullptr, ASM: ArraySizeModifier::Normal, IndexTypeQuals: 0);
3793	Expr *Lit =
3794	StringLiteral::Create(Ctx: Context, Str: StringRef(TokSpelling.data(), Length),
3795	Kind: StringLiteralKind::Ordinary,
3796	/*Pascal*/ false, Ty: StrTy, Locs: TokLoc);
3797	return BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args: Lit, LitEndLoc: TokLoc);
3798	}
3799
3800	case LOLR_Template: {
3801	// C++11 [lit.ext]p3, p4: Otherwise (S contains a literal operator
3802	// template), L is treated as a call fo the form
3803	// operator "" X <'c1', 'c2', ... 'ck'>()
3804	// where n is the source character sequence c1 c2 ... ck.
3805	TemplateArgumentListInfo ExplicitArgs;
3806	unsigned CharBits = Context.getIntWidth(T: Context.CharTy);
3807	bool CharIsUnsigned = Context.CharTy->isUnsignedIntegerType();
3808	llvm::APSInt Value(CharBits, CharIsUnsigned);
3809	for (unsigned I = 0, N = Literal.getUDSuffixOffset(); I != N; ++I) {
3810	Value = TokSpelling[I];
3811	TemplateArgument Arg(Context, Value, Context.CharTy);
3812	TemplateArgumentLocInfo ArgInfo;
3813	ExplicitArgs.addArgument(Loc: TemplateArgumentLoc(Arg, ArgInfo));
3814	}
3815	return BuildLiteralOperatorCall(R, SuffixInfo&: OpNameInfo, Args: {}, LitEndLoc: TokLoc, ExplicitTemplateArgs: &ExplicitArgs);
3816	}
3817	case LOLR_StringTemplatePack:
3818	llvm_unreachable("unexpected literal operator lookup result");
3819	}
3820	}
3821
3822	Expr *Res;
3823
3824	if (Literal.isFixedPointLiteral()) {
3825	QualType Ty;
3826
3827	if (Literal.isAccum) {
3828	if (Literal.isHalf) {
3829	Ty = Context.ShortAccumTy;
3830	} else if (Literal.isLong) {
3831	Ty = Context.LongAccumTy;
3832	} else {
3833	Ty = Context.AccumTy;
3834	}
3835	} else if (Literal.isFract) {
3836	if (Literal.isHalf) {
3837	Ty = Context.ShortFractTy;
3838	} else if (Literal.isLong) {
3839	Ty = Context.LongFractTy;
3840	} else {
3841	Ty = Context.FractTy;
3842	}
3843	}
3844
3845	if (Literal.isUnsigned) Ty = Context.getCorrespondingUnsignedType(T: Ty);
3846
3847	bool isSigned = !Literal.isUnsigned;
3848	unsigned scale = Context.getFixedPointScale(Ty);
3849	unsigned bit_width = Context.getTypeInfo(T: Ty).Width;
3850
3851	llvm::APInt Val(bit_width, 0, isSigned);
3852	bool Overflowed = Literal.GetFixedPointValue(StoreVal&: Val, Scale: scale);
3853	bool ValIsZero = Val.isZero() && !Overflowed;
3854
3855	auto MaxVal = Context.getFixedPointMax(Ty).getValue();
3856	if (Literal.isFract && Val == MaxVal + 1 && !ValIsZero)
3857	// Clause 6.4.4 - The value of a constant shall be in the range of
3858	// representable values for its type, with exception for constants of a
3859	// fract type with a value of exactly 1; such a constant shall denote
3860	// the maximal value for the type.
3861	--Val;
3862	else if (Val.ugt(RHS: MaxVal) || Overflowed)
3863	Diag(Loc: Tok.getLocation(), DiagID: diag::err_too_large_for_fixed_point);
3864
3865	Res = FixedPointLiteral::CreateFromRawInt(C: Context, V: Val, type: Ty,
3866	l: Tok.getLocation(), Scale: scale);
3867	} else if (Literal.isFloatingLiteral()) {
3868	QualType Ty;
3869	if (Literal.isHalf){
3870	if (getLangOpts().HLSL ||
3871	getOpenCLOptions().isAvailableOption(Ext: "cl_khr_fp16", LO: getLangOpts()))
3872	Ty = Context.HalfTy;
3873	else {
3874	Diag(Loc: Tok.getLocation(), DiagID: diag::err_half_const_requires_fp16);
3875	return ExprError();
3876	}
3877	} else if (Literal.isFloat)
3878	Ty = Context.FloatTy;
3879	else if (Literal.isLong)
3880	Ty = !getLangOpts().HLSL ? Context.LongDoubleTy : Context.DoubleTy;
3881	else if (Literal.isFloat16)
3882	Ty = Context.Float16Ty;
3883	else if (Literal.isFloat128)
3884	Ty = Context.Float128Ty;
3885	else if (getLangOpts().HLSL)
3886	Ty = Context.FloatTy;
3887	else
3888	Ty = Context.DoubleTy;
3889
3890	Res = BuildFloatingLiteral(S&: *this, Literal, Ty, Loc: Tok.getLocation());
3891
3892	if (Ty == Context.DoubleTy) {
3893	if (getLangOpts().SinglePrecisionConstants) {
3894	if (Ty->castAs<BuiltinType>()->getKind() != BuiltinType::Float) {
3895	Res = ImpCastExprToType(E: Res, Type: Context.FloatTy, CK: CK_FloatingCast).get();
3896	}
3897	} else if (getLangOpts().OpenCL && !getOpenCLOptions().isAvailableOption(
3898	Ext: "cl_khr_fp64", LO: getLangOpts())) {
3899	// Impose single-precision float type when cl_khr_fp64 is not enabled.
3900	Diag(Loc: Tok.getLocation(), DiagID: diag::warn_double_const_requires_fp64)
3901	<< (getLangOpts().getOpenCLCompatibleVersion() >= 300);
3902	Res = ImpCastExprToType(E: Res, Type: Context.FloatTy, CK: CK_FloatingCast).get();
3903	}
3904	}
3905	} else if (!Literal.isIntegerLiteral()) {
3906	return ExprError();
3907	} else {
3908	QualType Ty;
3909
3910	// 'z/uz' literals are a C++23 feature.
3911	if (Literal.isSizeT)
3912	Diag(Loc: Tok.getLocation(), DiagID: getLangOpts().CPlusPlus
3913	? getLangOpts().CPlusPlus23
3914	? diag::warn_cxx20_compat_size_t_suffix
3915	: diag::ext_cxx23_size_t_suffix
3916	: diag::err_cxx23_size_t_suffix);
3917
3918	// 'wb/uwb' literals are a C23 feature. We support _BitInt as a type in C++,
3919	// but we do not currently support the suffix in C++ mode because it's not
3920	// entirely clear whether WG21 will prefer this suffix to return a library
3921	// type such as std::bit_int instead of returning a _BitInt. '__wb/__uwb'
3922	// literals are a C++ extension.
3923	if (Literal.isBitInt)
3924	PP.Diag(Loc: Tok.getLocation(),
3925	DiagID: getLangOpts().CPlusPlus ? diag::ext_cxx_bitint_suffix
3926	: getLangOpts().C23 ? diag::warn_c23_compat_bitint_suffix
3927	: diag::ext_c23_bitint_suffix);
3928
3929	// Get the value in the widest-possible width. What is "widest" depends on
3930	// whether the literal is a bit-precise integer or not. For a bit-precise
3931	// integer type, try to scan the source to determine how many bits are
3932	// needed to represent the value. This may seem a bit expensive, but trying
3933	// to get the integer value from an overly-wide APInt is *extremely*
3934	// expensive, so the naive approach of assuming
3935	// llvm::IntegerType::MAX_INT_BITS is a big performance hit.
3936	unsigned BitsNeeded = Context.getTargetInfo().getIntMaxTWidth();
3937	if (Literal.isBitInt)
3938	BitsNeeded = llvm::APInt::getSufficientBitsNeeded(
3939	Str: Literal.getLiteralDigits(), Radix: Literal.getRadix());
3940	if (Literal.MicrosoftInteger) {
3941	if (Literal.MicrosoftInteger == 128 &&
3942	!Context.getTargetInfo().hasInt128Type())
3943	PP.Diag(Loc: Tok.getLocation(), DiagID: diag::err_integer_literal_too_large)
3944	<< Literal.isUnsigned;
3945	BitsNeeded = Literal.MicrosoftInteger;
3946	}
3947
3948	llvm::APInt ResultVal(BitsNeeded, 0);
3949
3950	if (Literal.GetIntegerValue(Val&: ResultVal)) {
3951	// If this value didn't fit into uintmax_t, error and force to ull.
3952	Diag(Loc: Tok.getLocation(), DiagID: diag::err_integer_literal_too_large)
3953	<< /* Unsigned */ 1;
3954	Ty = Context.UnsignedLongLongTy;
3955	assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() &&
3956	"long long is not intmax_t?");
3957	} else {
3958	// If this value fits into a ULL, try to figure out what else it fits into
3959	// according to the rules of C99 6.4.4.1p5.
3960
3961	// Octal, Hexadecimal, and integers with a U suffix are allowed to
3962	// be an unsigned int.
3963	bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10;
3964
3965	// HLSL doesn't really have `long` or `long long`. We support the `ll`
3966	// suffix for portability of code with C++, but both `l` and `ll` are
3967	// 64-bit integer types, and we want the type of `1l` and `1ll` to be the
3968	// same.
3969	if (getLangOpts().HLSL && !Literal.isLong && Literal.isLongLong) {
3970	Literal.isLong = true;
3971	Literal.isLongLong = false;
3972	}
3973
3974	// Check from smallest to largest, picking the smallest type we can.
3975	unsigned Width = 0;
3976
3977	// Microsoft specific integer suffixes are explicitly sized.
3978	if (Literal.MicrosoftInteger) {
3979	if (Literal.MicrosoftInteger == 8 && !Literal.isUnsigned) {
3980	Width = 8;
3981	Ty = Context.CharTy;
3982	} else {
3983	Width = Literal.MicrosoftInteger;
3984	Ty = Context.getIntTypeForBitwidth(DestWidth: Width,
3985	/*Signed=*/!Literal.isUnsigned);
3986	}
3987	}
3988
3989	// Bit-precise integer literals are automagically-sized based on the
3990	// width required by the literal.
3991	if (Literal.isBitInt) {
3992	// The signed version has one more bit for the sign value. There are no
3993	// zero-width bit-precise integers, even if the literal value is 0.
3994	Width = std::max(a: ResultVal.getActiveBits(), b: 1u) +
3995	(Literal.isUnsigned ? 0u : 1u);
3996
3997	// Diagnose if the width of the constant is larger than BITINT_MAXWIDTH,
3998	// and reset the type to the largest supported width.
3999	unsigned int MaxBitIntWidth =
4000	Context.getTargetInfo().getMaxBitIntWidth();
4001	if (Width > MaxBitIntWidth) {
4002	Diag(Loc: Tok.getLocation(), DiagID: diag::err_integer_literal_too_large)
4003	<< Literal.isUnsigned;
4004	Width = MaxBitIntWidth;
4005	}
4006
4007	// Reset the result value to the smaller APInt and select the correct
4008	// type to be used. Note, we zext even for signed values because the
4009	// literal itself is always an unsigned value (a preceeding - is a
4010	// unary operator, not part of the literal).
4011	ResultVal = ResultVal.zextOrTrunc(width: Width);
4012	Ty = Context.getBitIntType(Unsigned: Literal.isUnsigned, NumBits: Width);
4013	}
4014
4015	// Check C++23 size_t literals.
4016	if (Literal.isSizeT) {
4017	assert(!Literal.MicrosoftInteger &&
4018	"size_t literals can't be Microsoft literals");
4019	unsigned SizeTSize = Context.getTargetInfo().getTypeWidth(
4020	T: Context.getTargetInfo().getSizeType());
4021
4022	// Does it fit in size_t?
4023	if (ResultVal.isIntN(N: SizeTSize)) {
4024	// Does it fit in ssize_t?
4025	if (!Literal.isUnsigned && ResultVal[SizeTSize - 1] == 0)
4026	Ty = Context.getSignedSizeType();
4027	else if (AllowUnsigned)
4028	Ty = Context.getSizeType();
4029	Width = SizeTSize;
4030	}
4031	}
4032
4033	if (Ty.isNull() && !Literal.isLong && !Literal.isLongLong &&
4034	!Literal.isSizeT) {
4035	// Are int/unsigned possibilities?
4036	unsigned IntSize = Context.getTargetInfo().getIntWidth();
4037
4038	// Does it fit in a unsigned int?
4039	if (ResultVal.isIntN(N: IntSize)) {
4040	// Does it fit in a signed int?
4041	if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0)
4042	Ty = Context.IntTy;
4043	else if (AllowUnsigned)
4044	Ty = Context.UnsignedIntTy;
4045	Width = IntSize;
4046	}
4047	}
4048
4049	// Are long/unsigned long possibilities?
4050	if (Ty.isNull() && !Literal.isLongLong && !Literal.isSizeT) {
4051	unsigned LongSize = Context.getTargetInfo().getLongWidth();
4052
4053	// Does it fit in a unsigned long?
4054	if (ResultVal.isIntN(N: LongSize)) {
4055	// Does it fit in a signed long?
4056	if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0)
4057	Ty = Context.LongTy;
4058	else if (AllowUnsigned)
4059	Ty = Context.UnsignedLongTy;
4060	// Check according to the rules of C90 6.1.3.2p5. C++03 [lex.icon]p2
4061	// is compatible.
4062	else if (!getLangOpts().C99 && !getLangOpts().CPlusPlus11) {
4063	const unsigned LongLongSize =
4064	Context.getTargetInfo().getLongLongWidth();
4065	Diag(Loc: Tok.getLocation(),
4066	DiagID: getLangOpts().CPlusPlus
4067	? Literal.isLong
4068	? diag::warn_old_implicitly_unsigned_long_cxx
4069	: /*C++98 UB*/ diag::
4070	ext_old_implicitly_unsigned_long_cxx
4071	: diag::warn_old_implicitly_unsigned_long)
4072	<< (LongLongSize > LongSize ? /*will have type 'long long'*/ 0
4073	: /*will be ill-formed*/ 1);
4074	Ty = Context.UnsignedLongTy;
4075	}
4076	Width = LongSize;
4077	}
4078	}
4079
4080	// Check long long if needed.
4081	if (Ty.isNull() && !Literal.isSizeT) {
4082	unsigned LongLongSize = Context.getTargetInfo().getLongLongWidth();
4083
4084	// Does it fit in a unsigned long long?
4085	if (ResultVal.isIntN(N: LongLongSize)) {
4086	// Does it fit in a signed long long?
4087	// To be compatible with MSVC, hex integer literals ending with the
4088	// LL or i64 suffix are always signed in Microsoft mode.
4089	if (!Literal.isUnsigned && (ResultVal[LongLongSize-1] == 0 ||
4090	(getLangOpts().MSVCCompat && Literal.isLongLong)))
4091	Ty = Context.LongLongTy;
4092	else if (AllowUnsigned)
4093	Ty = Context.UnsignedLongLongTy;
4094	Width = LongLongSize;
4095
4096	// 'long long' is a C99 or C++11 feature, whether the literal
4097	// explicitly specified 'long long' or we needed the extra width.
4098	if (getLangOpts().CPlusPlus)
4099	Diag(Loc: Tok.getLocation(), DiagID: getLangOpts().CPlusPlus11
4100	? diag::warn_cxx98_compat_longlong
4101	: diag::ext_cxx11_longlong);
4102	else if (!getLangOpts().C99)
4103	Diag(Loc: Tok.getLocation(), DiagID: diag::ext_c99_longlong);
4104	}
4105	}
4106
4107	// If we still couldn't decide a type, we either have 'size_t' literal
4108	// that is out of range, or a decimal literal that does not fit in a
4109	// signed long long and has no U suffix.
4110	if (Ty.isNull()) {
4111	if (Literal.isSizeT)
4112	Diag(Loc: Tok.getLocation(), DiagID: diag::err_size_t_literal_too_large)
4113	<< Literal.isUnsigned;
4114	else
4115	Diag(Loc: Tok.getLocation(),
4116	DiagID: diag::ext_integer_literal_too_large_for_signed);
4117	Ty = Context.UnsignedLongLongTy;
4118	Width = Context.getTargetInfo().getLongLongWidth();
4119	}
4120
4121	if (ResultVal.getBitWidth() != Width)
4122	ResultVal = ResultVal.trunc(width: Width);
4123	}
4124	Res = IntegerLiteral::Create(C: Context, V: ResultVal, type: Ty, l: Tok.getLocation());
4125	}
4126
4127	// If this is an imaginary literal, create the ImaginaryLiteral wrapper.
4128	if (Literal.isImaginary) {
4129	Res = new (Context) ImaginaryLiteral(Res,
4130	Context.getComplexType(T: Res->getType()));
4131
4132	// In C++, this is a GNU extension. In C, it's a C2y extension.
4133	unsigned DiagId;
4134	if (getLangOpts().CPlusPlus)
4135	DiagId = diag::ext_gnu_imaginary_constant;
4136	else if (getLangOpts().C2y)
4137	DiagId = diag::warn_c23_compat_imaginary_constant;
4138	else
4139	DiagId = diag::ext_c2y_imaginary_constant;
4140	Diag(Loc: Tok.getLocation(), DiagID: DiagId);
4141	}
4142	return Res;
4143	}
4144
4145	ExprResult Sema::ActOnParenExpr(SourceLocation L, SourceLocation R, Expr *E) {
4146	assert(E && "ActOnParenExpr() missing expr");
4147	QualType ExprTy = E->getType();
4148	if (getLangOpts().ProtectParens && CurFPFeatures.getAllowFPReassociate() &&
4149	!E->isLValue() && ExprTy->hasFloatingRepresentation())
4150	return BuildBuiltinCallExpr(Loc: R, Id: Builtin::BI__arithmetic_fence, CallArgs: E);
4151	return new (Context) ParenExpr(L, R, E);
4152	}
4153
4154	static bool CheckVecStepTraitOperandType(Sema &S, QualType T,
4155	SourceLocation Loc,
4156	SourceRange ArgRange) {
4157	// [OpenCL 1.1 6.11.12] "The vec_step built-in function takes a built-in
4158	// scalar or vector data type argument..."
4159	// Every built-in scalar type (OpenCL 1.1 6.1.1) is either an arithmetic
4160	// type (C99 6.2.5p18) or void.
4161	if (!(T->isArithmeticType() || T->isVoidType() || T->isVectorType())) {
4162	S.Diag(Loc, DiagID: diag::err_vecstep_non_scalar_vector_type)
4163	<< T << ArgRange;
4164	return true;
4165	}
4166
4167	assert((T->isVoidType() || !T->isIncompleteType()) &&
4168	"Scalar types should always be complete");
4169	return false;
4170	}
4171
4172	static bool CheckVectorElementsTraitOperandType(Sema &S, QualType T,
4173	SourceLocation Loc,
4174	SourceRange ArgRange) {
4175	// builtin_vectorelements supports both fixed-sized and scalable vectors.
4176	if (!T->isVectorType() && !T->isSizelessVectorType())
4177	return S.Diag(Loc, DiagID: diag::err_builtin_non_vector_type)
4178	<< ""
4179	<< "__builtin_vectorelements" << T << ArgRange;
4180
4181	return false;
4182	}
4183
4184	static bool checkPtrAuthTypeDiscriminatorOperandType(Sema &S, QualType T,
4185	SourceLocation Loc,
4186	SourceRange ArgRange) {
4187	if (S.checkPointerAuthEnabled(Loc, Range: ArgRange))
4188	return true;
4189
4190	if (!T->isFunctionType() && !T->isFunctionPointerType() &&
4191	!T->isFunctionReferenceType() && !T->isMemberFunctionPointerType()) {
4192	S.Diag(Loc, DiagID: diag::err_ptrauth_type_disc_undiscriminated) << T << ArgRange;
4193	return true;
4194	}
4195
4196	return false;
4197	}
4198
4199	static bool CheckExtensionTraitOperandType(Sema &S, QualType T,
4200	SourceLocation Loc,
4201	SourceRange ArgRange,
4202	UnaryExprOrTypeTrait TraitKind) {
4203	// Invalid types must be hard errors for SFINAE in C++.
4204	if (S.LangOpts.CPlusPlus)
4205	return true;
4206
4207	// C99 6.5.3.4p1:
4208	if (T->isFunctionType() &&
4209	(TraitKind == UETT_SizeOf || TraitKind == UETT_AlignOf ||
4210	TraitKind == UETT_PreferredAlignOf)) {
4211	// sizeof(function)/alignof(function) is allowed as an extension.
4212	S.Diag(Loc, DiagID: diag::ext_sizeof_alignof_function_type)
4213	<< getTraitSpelling(T: TraitKind) << ArgRange;
4214	return false;
4215	}
4216
4217	// Allow sizeof(void)/alignof(void) as an extension, unless in OpenCL where
4218	// this is an error (OpenCL v1.1 s6.3.k)
4219	if (T->isVoidType()) {
4220	unsigned DiagID = S.LangOpts.OpenCL ? diag::err_opencl_sizeof_alignof_type
4221	: diag::ext_sizeof_alignof_void_type;
4222	S.Diag(Loc, DiagID) << getTraitSpelling(T: TraitKind) << ArgRange;
4223	return false;
4224	}
4225
4226	return true;
4227	}
4228
4229	static bool CheckObjCTraitOperandConstraints(Sema &S, QualType T,
4230	SourceLocation Loc,
4231	SourceRange ArgRange,
4232	UnaryExprOrTypeTrait TraitKind) {
4233	// Reject sizeof(interface) and sizeof(interface<proto>) if the
4234	// runtime doesn't allow it.
4235	if (!S.LangOpts.ObjCRuntime.allowsSizeofAlignof() && T->isObjCObjectType()) {
4236	S.Diag(Loc, DiagID: diag::err_sizeof_nonfragile_interface)
4237	<< T << (TraitKind == UETT_SizeOf)
4238	<< ArgRange;
4239	return true;
4240	}
4241
4242	return false;
4243	}
4244
4245	/// Check whether E is a pointer from a decayed array type (the decayed
4246	/// pointer type is equal to T) and emit a warning if it is.
4247	static void warnOnSizeofOnArrayDecay(Sema &S, SourceLocation Loc, QualType T,
4248	const Expr *E) {
4249	// Don't warn if the operation changed the type.
4250	if (T != E->getType())
4251	return;
4252
4253	// Now look for array decays.
4254	const auto *ICE = dyn_cast<ImplicitCastExpr>(Val: E);
4255	if (!ICE || ICE->getCastKind() != CK_ArrayToPointerDecay)
4256	return;
4257
4258	S.Diag(Loc, DiagID: diag::warn_sizeof_array_decay) << ICE->getSourceRange()
4259	<< ICE->getType()
4260	<< ICE->getSubExpr()->getType();
4261	}
4262
4263	bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E,
4264	UnaryExprOrTypeTrait ExprKind) {
4265	QualType ExprTy = E->getType();
4266	assert(!ExprTy->isReferenceType());
4267
4268	bool IsUnevaluatedOperand =
4269	(ExprKind == UETT_SizeOf || ExprKind == UETT_DataSizeOf ||
4270	ExprKind == UETT_AlignOf || ExprKind == UETT_PreferredAlignOf ||
4271	ExprKind == UETT_VecStep || ExprKind == UETT_CountOf);
4272	if (IsUnevaluatedOperand) {
4273	ExprResult Result = CheckUnevaluatedOperand(E);
4274	if (Result.isInvalid())
4275	return true;
4276	E = Result.get();
4277	}
4278
4279	// The operand for sizeof and alignof is in an unevaluated expression context,
4280	// so side effects could result in unintended consequences.
4281	// Exclude instantiation-dependent expressions, because 'sizeof' is sometimes
4282	// used to build SFINAE gadgets.
4283	// FIXME: Should we consider instantiation-dependent operands to 'alignof'?
4284	if (IsUnevaluatedOperand && !inTemplateInstantiation() &&
4285	!E->isInstantiationDependent() &&
4286	!E->getType()->isVariableArrayType() &&
4287	E->HasSideEffects(Ctx: Context, IncludePossibleEffects: false))
4288	Diag(Loc: E->getExprLoc(), DiagID: diag::warn_side_effects_unevaluated_context);
4289
4290	if (ExprKind == UETT_VecStep)
4291	return CheckVecStepTraitOperandType(S&: *this, T: ExprTy, Loc: E->getExprLoc(),
4292	ArgRange: E->getSourceRange());
4293
4294	if (ExprKind == UETT_VectorElements)
4295	return CheckVectorElementsTraitOperandType(S&: *this, T: ExprTy, Loc: E->getExprLoc(),
4296	ArgRange: E->getSourceRange());
4297
4298	// Explicitly list some types as extensions.
4299	if (!CheckExtensionTraitOperandType(S&: *this, T: ExprTy, Loc: E->getExprLoc(),
4300	ArgRange: E->getSourceRange(), TraitKind: ExprKind))
4301	return false;
4302
4303	// WebAssembly tables are always illegal operands to unary expressions and
4304	// type traits.
4305	if (Context.getTargetInfo().getTriple().isWasm() &&
4306	E->getType()->isWebAssemblyTableType()) {
4307	Diag(Loc: E->getExprLoc(), DiagID: diag::err_wasm_table_invalid_uett_operand)
4308	<< getTraitSpelling(T: ExprKind);
4309	return true;
4310	}
4311
4312	// 'alignof' applied to an expression only requires the base element type of
4313	// the expression to be complete. 'sizeof' requires the expression's type to
4314	// be complete (and will attempt to complete it if it's an array of unknown
4315	// bound).
4316	if (ExprKind == UETT_AlignOf || ExprKind == UETT_PreferredAlignOf) {
4317	if (RequireCompleteSizedType(
4318	Loc: E->getExprLoc(), T: Context.getBaseElementType(QT: E->getType()),
4319	DiagID: diag::err_sizeof_alignof_incomplete_or_sizeless_type,
4320	Args: getTraitSpelling(T: ExprKind), Args: E->getSourceRange()))
4321	return true;
4322	} else {
4323	if (RequireCompleteSizedExprType(
4324	E, DiagID: diag::err_sizeof_alignof_incomplete_or_sizeless_type,
4325	Args: getTraitSpelling(T: ExprKind), Args: E->getSourceRange()))
4326	return true;
4327	}
4328
4329	// Completing the expression's type may have changed it.
4330	ExprTy = E->getType();
4331	assert(!ExprTy->isReferenceType());
4332
4333	if (ExprTy->isFunctionType()) {
4334	Diag(Loc: E->getExprLoc(), DiagID: diag::err_sizeof_alignof_function_type)
4335	<< getTraitSpelling(T: ExprKind) << E->getSourceRange();
4336	return true;
4337	}
4338
4339	if (CheckObjCTraitOperandConstraints(S&: *this, T: ExprTy, Loc: E->getExprLoc(),
4340	ArgRange: E->getSourceRange(), TraitKind: ExprKind))
4341	return true;
4342
4343	if (ExprKind == UETT_CountOf) {
4344	// The type has to be an array type. We already checked for incomplete
4345	// types above.
4346	QualType ExprType = E->IgnoreParens()->getType();
4347	if (!ExprType->isArrayType()) {
4348	Diag(Loc: E->getExprLoc(), DiagID: diag::err_countof_arg_not_array_type) << ExprType;
4349	return true;
4350	}
4351	// FIXME: warn on _Countof on an array parameter. Not warning on it
4352	// currently because there are papers in WG14 about array types which do
4353	// not decay that could impact this behavior, so we want to see if anything
4354	// changes here before coming up with a warning group for _Countof-related
4355	// diagnostics.
4356	}
4357
4358	if (ExprKind == UETT_SizeOf) {
4359	if (const auto *DeclRef = dyn_cast<DeclRefExpr>(Val: E->IgnoreParens())) {
4360	if (const auto *PVD = dyn_cast<ParmVarDecl>(Val: DeclRef->getFoundDecl())) {
4361	QualType OType = PVD->getOriginalType();
4362	QualType Type = PVD->getType();
4363	if (Type->isPointerType() && OType->isArrayType()) {
4364	Diag(Loc: E->getExprLoc(), DiagID: diag::warn_sizeof_array_param)
4365	<< Type << OType;
4366	Diag(Loc: PVD->getLocation(), DiagID: diag::note_declared_at);
4367	}
4368	}
4369	}
4370
4371	// Warn on "sizeof(array op x)" and "sizeof(x op array)", where the array
4372	// decays into a pointer and returns an unintended result. This is most
4373	// likely a typo for "sizeof(array) op x".
4374	if (const auto *BO = dyn_cast<BinaryOperator>(Val: E->IgnoreParens())) {
4375	warnOnSizeofOnArrayDecay(S&: *this, Loc: BO->getOperatorLoc(), T: BO->getType(),
4376	E: BO->getLHS());
4377	warnOnSizeofOnArrayDecay(S&: *this, Loc: BO->getOperatorLoc(), T: BO->getType(),
4378	E: BO->getRHS());
4379	}
4380	}
4381
4382	return false;
4383	}
4384
4385	static bool CheckAlignOfExpr(Sema &S, Expr *E, UnaryExprOrTypeTrait ExprKind) {
4386	// Cannot know anything else if the expression is dependent.
4387	if (E->isTypeDependent())
4388	return false;
4389
4390	if (E->getObjectKind() == OK_BitField) {
4391	S.Diag(Loc: E->getExprLoc(), DiagID: diag::err_sizeof_alignof_typeof_bitfield)
4392	<< 1 << E->getSourceRange();
4393	return true;
4394	}
4395
4396	ValueDecl *D = nullptr;
4397	Expr *Inner = E->IgnoreParens();
4398	if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: Inner)) {
4399	D = DRE->getDecl();
4400	} else if (MemberExpr *ME = dyn_cast<MemberExpr>(Val: Inner)) {
4401	D = ME->getMemberDecl();
4402	}
4403
4404	// If it's a field, require the containing struct to have a
4405	// complete definition so that we can compute the layout.
4406	//
4407	// This can happen in C++11 onwards, either by naming the member
4408	// in a way that is not transformed into a member access expression
4409	// (in an unevaluated operand, for instance), or by naming the member
4410	// in a trailing-return-type.
4411	//
4412	// For the record, since __alignof__ on expressions is a GCC
4413	// extension, GCC seems to permit this but always gives the
4414	// nonsensical answer 0.
4415	//
4416	// We don't really need the layout here --- we could instead just
4417	// directly check for all the appropriate alignment-lowing
4418	// attributes --- but that would require duplicating a lot of
4419	// logic that just isn't worth duplicating for such a marginal
4420	// use-case.
4421	if (FieldDecl *FD = dyn_cast_or_null<FieldDecl>(Val: D)) {
4422	// Fast path this check, since we at least know the record has a
4423	// definition if we can find a member of it.
4424	if (!FD->getParent()->isCompleteDefinition()) {
4425	S.Diag(Loc: E->getExprLoc(), DiagID: diag::err_alignof_member_of_incomplete_type)
4426	<< E->getSourceRange();
4427	return true;
4428	}
4429
4430	// Otherwise, if it's a field, and the field doesn't have
4431	// reference type, then it must have a complete type (or be a
4432	// flexible array member, which we explicitly want to
4433	// white-list anyway), which makes the following checks trivial.
4434	if (!FD->getType()->isReferenceType())
4435	return false;
4436	}
4437
4438	return S.CheckUnaryExprOrTypeTraitOperand(E, ExprKind);
4439	}
4440
4441	bool Sema::CheckVecStepExpr(Expr *E) {
4442	E = E->IgnoreParens();
4443
4444	// Cannot know anything else if the expression is dependent.
4445	if (E->isTypeDependent())
4446	return false;
4447
4448	return CheckUnaryExprOrTypeTraitOperand(E, ExprKind: UETT_VecStep);
4449	}
4450
4451	static void captureVariablyModifiedType(ASTContext &Context, QualType T,
4452	CapturingScopeInfo *CSI) {
4453	assert(T->isVariablyModifiedType());
4454	assert(CSI != nullptr);
4455
4456	// We're going to walk down into the type and look for VLA expressions.
4457	do {
4458	const Type *Ty = T.getTypePtr();
4459	switch (Ty->getTypeClass()) {
4460	#define TYPE(Class, Base)
4461	#define ABSTRACT_TYPE(Class, Base)
4462	#define NON_CANONICAL_TYPE(Class, Base)
4463	#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4464	#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)
4465	#include "clang/AST/TypeNodes.inc"
4466	T = QualType();
4467	break;
4468	// These types are never variably-modified.
4469	case Type::Builtin:
4470	case Type::Complex:
4471	case Type::Vector:
4472	case Type::ExtVector:
4473	case Type::ConstantMatrix:
4474	case Type::Record:
4475	case Type::Enum:
4476	case Type::TemplateSpecialization:
4477	case Type::ObjCObject:
4478	case Type::ObjCInterface:
4479	case Type::ObjCObjectPointer:
4480	case Type::ObjCTypeParam:
4481	case Type::Pipe:
4482	case Type::BitInt:
4483	case Type::HLSLInlineSpirv:
4484	llvm_unreachable("type class is never variably-modified!");
4485	case Type::Elaborated:
4486	T = cast<ElaboratedType>(Val: Ty)->getNamedType();
4487	break;
4488	case Type::Adjusted:
4489	T = cast<AdjustedType>(Val: Ty)->getOriginalType();
4490	break;
4491	case Type::Decayed:
4492	T = cast<DecayedType>(Val: Ty)->getPointeeType();
4493	break;
4494	case Type::ArrayParameter:
4495	T = cast<ArrayParameterType>(Val: Ty)->getElementType();
4496	break;
4497	case Type::Pointer:
4498	T = cast<PointerType>(Val: Ty)->getPointeeType();
4499	break;
4500	case Type::BlockPointer:
4501	T = cast<BlockPointerType>(Val: Ty)->getPointeeType();
4502	break;
4503	case Type::LValueReference:
4504	case Type::RValueReference:
4505	T = cast<ReferenceType>(Val: Ty)->getPointeeType();
4506	break;
4507	case Type::MemberPointer:
4508	T = cast<MemberPointerType>(Val: Ty)->getPointeeType();
4509	break;
4510	case Type::ConstantArray:
4511	case Type::IncompleteArray:
4512	// Losing element qualification here is fine.
4513	T = cast<ArrayType>(Val: Ty)->getElementType();
4514	break;
4515	case Type::VariableArray: {
4516	// Losing element qualification here is fine.
4517	const VariableArrayType *VAT = cast<VariableArrayType>(Val: Ty);
4518
4519	// Unknown size indication requires no size computation.
4520	// Otherwise, evaluate and record it.
4521	auto Size = VAT->getSizeExpr();
4522	if (Size && !CSI->isVLATypeCaptured(VAT) &&
4523	(isa<CapturedRegionScopeInfo>(Val: CSI) || isa<LambdaScopeInfo>(Val: CSI)))
4524	CSI->addVLATypeCapture(Loc: Size->getExprLoc(), VLAType: VAT, CaptureType: Context.getSizeType());
4525
4526	T = VAT->getElementType();
4527	break;
4528	}
4529	case Type::FunctionProto:
4530	case Type::FunctionNoProto:
4531	T = cast<FunctionType>(Val: Ty)->getReturnType();
4532	break;
4533	case Type::Paren:
4534	case Type::TypeOf:
4535	case Type::UnaryTransform:
4536	case Type::Attributed:
4537	case Type::BTFTagAttributed:
4538	case Type::HLSLAttributedResource:
4539	case Type::SubstTemplateTypeParm:
4540	case Type::MacroQualified:
4541	case Type::CountAttributed:
4542	// Keep walking after single level desugaring.
4543	T = T.getSingleStepDesugaredType(Context);
4544	break;
4545	case Type::Typedef:
4546	T = cast<TypedefType>(Val: Ty)->desugar();
4547	break;
4548	case Type::Decltype:
4549	T = cast<DecltypeType>(Val: Ty)->desugar();
4550	break;
4551	case Type::PackIndexing:
4552	T = cast<PackIndexingType>(Val: Ty)->desugar();
4553	break;
4554	case Type::Using:
4555	T = cast<UsingType>(Val: Ty)->desugar();
4556	break;
4557	case Type::Auto:
4558	case Type::DeducedTemplateSpecialization:
4559	T = cast<DeducedType>(Val: Ty)->getDeducedType();
4560	break;
4561	case Type::TypeOfExpr:
4562	T = cast<TypeOfExprType>(Val: Ty)->getUnderlyingExpr()->getType();
4563	break;
4564	case Type::Atomic:
4565	T = cast<AtomicType>(Val: Ty)->getValueType();
4566	break;
4567	}
4568	} while (!T.isNull() && T->isVariablyModifiedType());
4569	}
4570
4571	bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType ExprType,
4572	SourceLocation OpLoc,
4573	SourceRange ExprRange,
4574	UnaryExprOrTypeTrait ExprKind,
4575	StringRef KWName) {
4576	if (ExprType->isDependentType())
4577	return false;
4578
4579	// C++ [expr.sizeof]p2:
4580	// When applied to a reference or a reference type, the result
4581	// is the size of the referenced type.
4582	// C++11 [expr.alignof]p3:
4583	// When alignof is applied to a reference type, the result
4584	// shall be the alignment of the referenced type.
4585	if (const ReferenceType *Ref = ExprType->getAs<ReferenceType>())
4586	ExprType = Ref->getPointeeType();
4587
4588	// C11 6.5.3.4/3, C++11 [expr.alignof]p3:
4589	// When alignof or _Alignof is applied to an array type, the result
4590	// is the alignment of the element type.
4591	if (ExprKind == UETT_AlignOf || ExprKind == UETT_PreferredAlignOf ||
4592	ExprKind == UETT_OpenMPRequiredSimdAlign) {
4593	// If the trait is 'alignof' in C before C2y, the ability to apply the
4594	// trait to an incomplete array is an extension.
4595	if (ExprKind == UETT_AlignOf && !getLangOpts().CPlusPlus &&
4596	ExprType->isIncompleteArrayType())
4597	Diag(Loc: OpLoc, DiagID: getLangOpts().C2y
4598	? diag::warn_c2y_compat_alignof_incomplete_array
4599	: diag::ext_c2y_alignof_incomplete_array);
4600	ExprType = Context.getBaseElementType(QT: ExprType);
4601	}
4602
4603	if (ExprKind == UETT_VecStep)
4604	return CheckVecStepTraitOperandType(S&: *this, T: ExprType, Loc: OpLoc, ArgRange: ExprRange);
4605
4606	if (ExprKind == UETT_VectorElements)
4607	return CheckVectorElementsTraitOperandType(S&: *this, T: ExprType, Loc: OpLoc,
4608	ArgRange: ExprRange);
4609
4610	if (ExprKind == UETT_PtrAuthTypeDiscriminator)
4611	return checkPtrAuthTypeDiscriminatorOperandType(S&: *this, T: ExprType, Loc: OpLoc,
4612	ArgRange: ExprRange);
4613
4614	// Explicitly list some types as extensions.
4615	if (!CheckExtensionTraitOperandType(S&: *this, T: ExprType, Loc: OpLoc, ArgRange: ExprRange,
4616	TraitKind: ExprKind))
4617	return false;
4618
4619	if (RequireCompleteSizedType(
4620	Loc: OpLoc, T: ExprType, DiagID: diag::err_sizeof_alignof_incomplete_or_sizeless_type,
4621	Args: KWName, Args: ExprRange))
4622	return true;
4623
4624	if (ExprType->isFunctionType()) {
4625	Diag(Loc: OpLoc, DiagID: diag::err_sizeof_alignof_function_type) << KWName << ExprRange;
4626	return true;
4627	}
4628
4629	if (ExprKind == UETT_CountOf) {
4630	// The type has to be an array type. We already checked for incomplete
4631	// types above.
4632	if (!ExprType->isArrayType()) {
4633	Diag(Loc: OpLoc, DiagID: diag::err_countof_arg_not_array_type) << ExprType;
4634	return true;
4635	}
4636	}
4637
4638	// WebAssembly tables are always illegal operands to unary expressions and
4639	// type traits.
4640	if (Context.getTargetInfo().getTriple().isWasm() &&
4641	ExprType->isWebAssemblyTableType()) {
4642	Diag(Loc: OpLoc, DiagID: diag::err_wasm_table_invalid_uett_operand)
4643	<< getTraitSpelling(T: ExprKind);
4644	return true;
4645	}
4646
4647	if (CheckObjCTraitOperandConstraints(S&: *this, T: ExprType, Loc: OpLoc, ArgRange: ExprRange,
4648	TraitKind: ExprKind))
4649	return true;
4650
4651	if (ExprType->isVariablyModifiedType() && FunctionScopes.size() > 1) {
4652	if (auto *TT = ExprType->getAs<TypedefType>()) {
4653	for (auto I = FunctionScopes.rbegin(),
4654	E = std::prev(x: FunctionScopes.rend());
4655	I != E; ++I) {
4656	auto *CSI = dyn_cast<CapturingScopeInfo>(Val: *I);
4657	if (CSI == nullptr)
4658	break;
4659	DeclContext *DC = nullptr;
4660	if (auto *LSI = dyn_cast<LambdaScopeInfo>(Val: CSI))
4661	DC = LSI->CallOperator;
4662	else if (auto *CRSI = dyn_cast<CapturedRegionScopeInfo>(Val: CSI))
4663	DC = CRSI->TheCapturedDecl;
4664	else if (auto *BSI = dyn_cast<BlockScopeInfo>(Val: CSI))
4665	DC = BSI->TheDecl;
4666	if (DC) {
4667	if (DC->containsDecl(D: TT->getDecl()))
4668	break;
4669	captureVariablyModifiedType(Context, T: ExprType, CSI);
4670	}
4671	}
4672	}
4673	}
4674
4675	return false;
4676	}
4677
4678	ExprResult Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo,
4679	SourceLocation OpLoc,
4680	UnaryExprOrTypeTrait ExprKind,
4681	SourceRange R) {
4682	if (!TInfo)
4683	return ExprError();
4684
4685	QualType T = TInfo->getType();
4686
4687	if (!T->isDependentType() &&
4688	CheckUnaryExprOrTypeTraitOperand(ExprType: T, OpLoc, ExprRange: R, ExprKind,
4689	KWName: getTraitSpelling(T: ExprKind)))
4690	return ExprError();
4691
4692	// Adds overload of TransformToPotentiallyEvaluated for TypeSourceInfo to
4693	// properly deal with VLAs in nested calls of sizeof and typeof.
4694	if (currentEvaluationContext().isUnevaluated() &&
4695	currentEvaluationContext().InConditionallyConstantEvaluateContext &&
4696	(ExprKind == UETT_SizeOf || ExprKind == UETT_CountOf) &&
4697	TInfo->getType()->isVariablyModifiedType())
4698	TInfo = TransformToPotentiallyEvaluated(TInfo);
4699
4700	// It's possible that the transformation above failed.
4701	if (!TInfo)
4702	return ExprError();
4703
4704	// C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
4705	return new (Context) UnaryExprOrTypeTraitExpr(
4706	ExprKind, TInfo, Context.getSizeType(), OpLoc, R.getEnd());
4707	}
4708
4709	ExprResult
4710	Sema::CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc,
4711	UnaryExprOrTypeTrait ExprKind) {
4712	ExprResult PE = CheckPlaceholderExpr(E);
4713	if (PE.isInvalid())
4714	return ExprError();
4715
4716	E = PE.get();
4717
4718	// Verify that the operand is valid.
4719	bool isInvalid = false;
4720	if (E->isTypeDependent()) {
4721	// Delay type-checking for type-dependent expressions.
4722	} else if (ExprKind == UETT_AlignOf || ExprKind == UETT_PreferredAlignOf) {
4723	isInvalid = CheckAlignOfExpr(S&: *this, E, ExprKind);
4724	} else if (ExprKind == UETT_VecStep) {
4725	isInvalid = CheckVecStepExpr(E);
4726	} else if (ExprKind == UETT_OpenMPRequiredSimdAlign) {
4727	Diag(Loc: E->getExprLoc(), DiagID: diag::err_openmp_default_simd_align_expr);
4728	isInvalid = true;
4729	} else if (E->refersToBitField()) { // C99 6.5.3.4p1.
4730	Diag(Loc: E->getExprLoc(), DiagID: diag::err_sizeof_alignof_typeof_bitfield) << 0;
4731	isInvalid = true;
4732	} else if (ExprKind == UETT_VectorElements || ExprKind == UETT_SizeOf ||
4733	ExprKind == UETT_CountOf) { // FIXME: __datasizeof?
4734	isInvalid = CheckUnaryExprOrTypeTraitOperand(E, ExprKind);
4735	}
4736
4737	if (isInvalid)
4738	return ExprError();
4739
4740	if ((ExprKind == UETT_SizeOf || ExprKind == UETT_CountOf) &&
4741	E->getType()->isVariableArrayType()) {
4742	PE = TransformToPotentiallyEvaluated(E);
4743	if (PE.isInvalid()) return ExprError();
4744	E = PE.get();
4745	}
4746
4747	// C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
4748	return new (Context) UnaryExprOrTypeTraitExpr(
4749	ExprKind, E, Context.getSizeType(), OpLoc, E->getSourceRange().getEnd());
4750	}
4751
4752	ExprResult
4753	Sema::ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc,
4754	UnaryExprOrTypeTrait ExprKind, bool IsType,
4755	void *TyOrEx, SourceRange ArgRange) {
4756	// If error parsing type, ignore.
4757	if (!TyOrEx) return ExprError();
4758
4759	if (IsType) {
4760	TypeSourceInfo *TInfo;
4761	(void) GetTypeFromParser(Ty: ParsedType::getFromOpaquePtr(P: TyOrEx), TInfo: &TInfo);
4762	return CreateUnaryExprOrTypeTraitExpr(TInfo, OpLoc, ExprKind, R: ArgRange);
4763	}
4764
4765	Expr *ArgEx = (Expr *)TyOrEx;
4766	ExprResult Result = CreateUnaryExprOrTypeTraitExpr(E: ArgEx, OpLoc, ExprKind);
4767	return Result;
4768	}
4769
4770	bool Sema::CheckAlignasTypeArgument(StringRef KWName, TypeSourceInfo *TInfo,
4771	SourceLocation OpLoc, SourceRange R) {
4772	if (!TInfo)
4773	return true;
4774	return CheckUnaryExprOrTypeTraitOperand(ExprType: TInfo->getType(), OpLoc, ExprRange: R,
4775	ExprKind: UETT_AlignOf, KWName);
4776	}
4777
4778	bool Sema::ActOnAlignasTypeArgument(StringRef KWName, ParsedType Ty,
4779	SourceLocation OpLoc, SourceRange R) {
4780	TypeSourceInfo *TInfo;
4781	(void)GetTypeFromParser(Ty: ParsedType::getFromOpaquePtr(P: Ty.getAsOpaquePtr()),
4782	TInfo: &TInfo);
4783	return CheckAlignasTypeArgument(KWName, TInfo, OpLoc, R);
4784	}
4785
4786	static QualType CheckRealImagOperand(Sema &S, ExprResult &V, SourceLocation Loc,
4787	bool IsReal) {
4788	if (V.get()->isTypeDependent())
4789	return S.Context.DependentTy;
4790
4791	// _Real and _Imag are only l-values for normal l-values.
4792	if (V.get()->getObjectKind() != OK_Ordinary) {
4793	V = S.DefaultLvalueConversion(E: V.get());
4794	if (V.isInvalid())
4795	return QualType();
4796	}
4797
4798	// These operators return the element type of a complex type.
4799	if (const ComplexType *CT = V.get()->getType()->getAs<ComplexType>())
4800	return CT->getElementType();
4801
4802	// Otherwise they pass through real integer and floating point types here.
4803	if (V.get()->getType()->isArithmeticType())
4804	return V.get()->getType();
4805
4806	// Test for placeholders.
4807	ExprResult PR = S.CheckPlaceholderExpr(E: V.get());
4808	if (PR.isInvalid()) return QualType();
4809	if (PR.get() != V.get()) {
4810	V = PR;
4811	return CheckRealImagOperand(S, V, Loc, IsReal);
4812	}
4813
4814	// Reject anything else.
4815	S.Diag(Loc, DiagID: diag::err_realimag_invalid_type) << V.get()->getType()
4816	<< (IsReal ? "__real" : "__imag");
4817	return QualType();
4818	}
4819
4820
4821
4822	ExprResult
4823	Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc,
4824	tok::TokenKind Kind, Expr *Input) {
4825	UnaryOperatorKind Opc;
4826	switch (Kind) {
4827	default: llvm_unreachable("Unknown unary op!");
4828	case tok::plusplus: Opc = UO_PostInc; break;
4829	case tok::minusminus: Opc = UO_PostDec; break;
4830	}
4831
4832	// Since this might is a postfix expression, get rid of ParenListExprs.
4833	ExprResult Result = MaybeConvertParenListExprToParenExpr(S, ME: Input);
4834	if (Result.isInvalid()) return ExprError();
4835	Input = Result.get();
4836
4837	return BuildUnaryOp(S, OpLoc, Opc, Input);
4838	}
4839
4840	/// Diagnose if arithmetic on the given ObjC pointer is illegal.
4841	///
4842	/// \return true on error
4843	static bool checkArithmeticOnObjCPointer(Sema &S,
4844	SourceLocation opLoc,
4845	Expr *op) {
4846	assert(op->getType()->isObjCObjectPointerType());
4847	if (S.LangOpts.ObjCRuntime.allowsPointerArithmetic() &&
4848	!S.LangOpts.ObjCSubscriptingLegacyRuntime)
4849	return false;
4850
4851	S.Diag(Loc: opLoc, DiagID: diag::err_arithmetic_nonfragile_interface)
4852	<< op->getType()->castAs<ObjCObjectPointerType>()->getPointeeType()
4853	<< op->getSourceRange();
4854	return true;
4855	}
4856
4857	static bool isMSPropertySubscriptExpr(Sema &S, Expr *Base) {
4858	auto *BaseNoParens = Base->IgnoreParens();
4859	if (auto *MSProp = dyn_cast<MSPropertyRefExpr>(Val: BaseNoParens))
4860	return MSProp->getPropertyDecl()->getType()->isArrayType();
4861	return isa<MSPropertySubscriptExpr>(Val: BaseNoParens);
4862	}
4863
4864	// Returns the type used for LHS[RHS], given one of LHS, RHS is type-dependent.
4865	// Typically this is DependentTy, but can sometimes be more precise.
4866	//
4867	// There are cases when we could determine a non-dependent type:
4868	// - LHS and RHS may have non-dependent types despite being type-dependent
4869	// (e.g. unbounded array static members of the current instantiation)
4870	// - one may be a dependent-sized array with known element type
4871	// - one may be a dependent-typed valid index (enum in current instantiation)
4872	//
4873	// We *always* return a dependent type, in such cases it is DependentTy.
4874	// This avoids creating type-dependent expressions with non-dependent types.
4875	// FIXME: is this important to avoid? See https://reviews.llvm.org/D107275
4876	static QualType getDependentArraySubscriptType(Expr *LHS, Expr *RHS,
4877	const ASTContext &Ctx) {
4878	assert(LHS->isTypeDependent() || RHS->isTypeDependent());
4879	QualType LTy = LHS->getType(), RTy = RHS->getType();
4880	QualType Result = Ctx.DependentTy;
4881	if (RTy->isIntegralOrUnscopedEnumerationType()) {
4882	if (const PointerType *PT = LTy->getAs<PointerType>())
4883	Result = PT->getPointeeType();
4884	else if (const ArrayType *AT = LTy->getAsArrayTypeUnsafe())
4885	Result = AT->getElementType();
4886	} else if (LTy->isIntegralOrUnscopedEnumerationType()) {
4887	if (const PointerType *PT = RTy->getAs<PointerType>())
4888	Result = PT->getPointeeType();
4889	else if (const ArrayType *AT = RTy->getAsArrayTypeUnsafe())
4890	Result = AT->getElementType();
4891	}
4892	// Ensure we return a dependent type.
4893	return Result->isDependentType() ? Result : Ctx.DependentTy;
4894	}
4895
4896	ExprResult Sema::ActOnArraySubscriptExpr(Scope *S, Expr *base,
4897	SourceLocation lbLoc,
4898	MultiExprArg ArgExprs,
4899	SourceLocation rbLoc) {
4900
4901	if (base && !base->getType().isNull() &&
4902	base->hasPlaceholderType(K: BuiltinType::ArraySection)) {
4903	auto *AS = cast<ArraySectionExpr>(Val: base);
4904	if (AS->isOMPArraySection())
4905	return OpenMP().ActOnOMPArraySectionExpr(
4906	Base: base, LBLoc: lbLoc, LowerBound: ArgExprs.front(), ColonLocFirst: SourceLocation(), ColonLocSecond: SourceLocation(),
4907	/*Length*/ nullptr,
4908	/*Stride=*/nullptr, RBLoc: rbLoc);
4909
4910	return OpenACC().ActOnArraySectionExpr(Base: base, LBLoc: lbLoc, LowerBound: ArgExprs.front(),
4911	ColonLocFirst: SourceLocation(), /*Length*/ nullptr,
4912	RBLoc: rbLoc);
4913	}
4914
4915	// Since this might be a postfix expression, get rid of ParenListExprs.
4916	if (isa<ParenListExpr>(Val: base)) {
4917	ExprResult result = MaybeConvertParenListExprToParenExpr(S, ME: base);
4918	if (result.isInvalid())
4919	return ExprError();
4920	base = result.get();
4921	}
4922
4923	// Check if base and idx form a MatrixSubscriptExpr.
4924	//
4925	// Helper to check for comma expressions, which are not allowed as indices for
4926	// matrix subscript expressions.
4927	auto CheckAndReportCommaError = [this, base, rbLoc](Expr *E) {
4928	if (isa<BinaryOperator>(Val: E) && cast<BinaryOperator>(Val: E)->isCommaOp()) {
4929	Diag(Loc: E->getExprLoc(), DiagID: diag::err_matrix_subscript_comma)
4930	<< SourceRange(base->getBeginLoc(), rbLoc);
4931	return true;
4932	}
4933	return false;
4934	};
4935	// The matrix subscript operator ([][])is considered a single operator.
4936	// Separating the index expressions by parenthesis is not allowed.
4937	if (base && !base->getType().isNull() &&
4938	base->hasPlaceholderType(K: BuiltinType::IncompleteMatrixIdx) &&
4939	!isa<MatrixSubscriptExpr>(Val: base)) {
4940	Diag(Loc: base->getExprLoc(), DiagID: diag::err_matrix_separate_incomplete_index)
4941	<< SourceRange(base->getBeginLoc(), rbLoc);
4942	return ExprError();
4943	}
4944	// If the base is a MatrixSubscriptExpr, try to create a new
4945	// MatrixSubscriptExpr.
4946	auto *matSubscriptE = dyn_cast<MatrixSubscriptExpr>(Val: base);
4947	if (matSubscriptE) {
4948	assert(ArgExprs.size() == 1);
4949	if (CheckAndReportCommaError(ArgExprs.front()))
4950	return ExprError();
4951
4952	assert(matSubscriptE->isIncomplete() &&
4953	"base has to be an incomplete matrix subscript");
4954	return CreateBuiltinMatrixSubscriptExpr(Base: matSubscriptE->getBase(),
4955	RowIdx: matSubscriptE->getRowIdx(),
4956	ColumnIdx: ArgExprs.front(), RBLoc: rbLoc);
4957	}
4958	if (base->getType()->isWebAssemblyTableType()) {
4959	Diag(Loc: base->getExprLoc(), DiagID: diag::err_wasm_table_art)
4960	<< SourceRange(base->getBeginLoc(), rbLoc) << 3;
4961	return ExprError();
4962	}
4963
4964	CheckInvalidBuiltinCountedByRef(E: base,
4965	K: BuiltinCountedByRefKind::ArraySubscript);
4966
4967	// Handle any non-overload placeholder types in the base and index
4968	// expressions. We can't handle overloads here because the other
4969	// operand might be an overloadable type, in which case the overload
4970	// resolution for the operator overload should get the first crack
4971	// at the overload.
4972	bool IsMSPropertySubscript = false;
4973	if (base->getType()->isNonOverloadPlaceholderType()) {
4974	IsMSPropertySubscript = isMSPropertySubscriptExpr(S&: *this, Base: base);
4975	if (!IsMSPropertySubscript) {
4976	ExprResult result = CheckPlaceholderExpr(E: base);
4977	if (result.isInvalid())
4978	return ExprError();
4979	base = result.get();
4980	}
4981	}
4982
4983	// If the base is a matrix type, try to create a new MatrixSubscriptExpr.
4984	if (base->getType()->isMatrixType()) {
4985	assert(ArgExprs.size() == 1);
4986	if (CheckAndReportCommaError(ArgExprs.front()))
4987	return ExprError();
4988
4989	return CreateBuiltinMatrixSubscriptExpr(Base: base, RowIdx: ArgExprs.front(), ColumnIdx: nullptr,
4990	RBLoc: rbLoc);
4991	}
4992
4993	if (ArgExprs.size() == 1 && getLangOpts().CPlusPlus20) {
4994	Expr *idx = ArgExprs[0];
4995	if ((isa<BinaryOperator>(Val: idx) && cast<BinaryOperator>(Val: idx)->isCommaOp()) ||
4996	(isa<CXXOperatorCallExpr>(Val: idx) &&
4997	cast<CXXOperatorCallExpr>(Val: idx)->getOperator() == OO_Comma)) {
4998	Diag(Loc: idx->getExprLoc(), DiagID: diag::warn_deprecated_comma_subscript)
4999	<< SourceRange(base->getBeginLoc(), rbLoc);
5000	}
5001	}
5002
5003	if (ArgExprs.size() == 1 &&
5004	ArgExprs[0]->getType()->isNonOverloadPlaceholderType()) {
5005	ExprResult result = CheckPlaceholderExpr(E: ArgExprs[0]);
5006	if (result.isInvalid())
5007	return ExprError();
5008	ArgExprs[0] = result.get();
5009	} else {
5010	if (CheckArgsForPlaceholders(args: ArgExprs))
5011	return ExprError();
5012	}
5013
5014	// Build an unanalyzed expression if either operand is type-dependent.
5015	if (getLangOpts().CPlusPlus && ArgExprs.size() == 1 &&
5016	(base->isTypeDependent() ||
5017	Expr::hasAnyTypeDependentArguments(Exprs: ArgExprs)) &&
5018	!isa<PackExpansionExpr>(Val: ArgExprs[0])) {
5019	return new (Context) ArraySubscriptExpr(
5020	base, ArgExprs.front(),
5021	getDependentArraySubscriptType(LHS: base, RHS: ArgExprs.front(), Ctx: getASTContext()),
5022	VK_LValue, OK_Ordinary, rbLoc);
5023	}
5024
5025	// MSDN, property (C++)
5026	// https://msdn.microsoft.com/en-us/library/yhfk0thd(v=vs.120).aspx
5027	// This attribute can also be used in the declaration of an empty array in a
5028	// class or structure definition. For example:
5029	// __declspec(property(get=GetX, put=PutX)) int x[];
5030	// The above statement indicates that x[] can be used with one or more array
5031	// indices. In this case, i=p->x[a][b] will be turned into i=p->GetX(a, b),
5032	// and p->x[a][b] = i will be turned into p->PutX(a, b, i);
5033	if (IsMSPropertySubscript) {
5034	assert(ArgExprs.size() == 1);
5035	// Build MS property subscript expression if base is MS property reference
5036	// or MS property subscript.
5037	return new (Context)
5038	MSPropertySubscriptExpr(base, ArgExprs.front(), Context.PseudoObjectTy,
5039	VK_LValue, OK_Ordinary, rbLoc);
5040	}
5041
5042	// Use C++ overloaded-operator rules if either operand has record
5043	// type. The spec says to do this if either type is *overloadable*,
5044	// but enum types can't declare subscript operators or conversion
5045	// operators, so there's nothing interesting for overload resolution
5046	// to do if there aren't any record types involved.
5047	//
5048	// ObjC pointers have their own subscripting logic that is not tied
5049	// to overload resolution and so should not take this path.
5050	if (getLangOpts().CPlusPlus && !base->getType()->isObjCObjectPointerType() &&
5051	((base->getType()->isRecordType() ||
5052	(ArgExprs.size() != 1 || isa<PackExpansionExpr>(Val: ArgExprs[0]) ||
5053	ArgExprs[0]->getType()->isRecordType())))) {
5054	return CreateOverloadedArraySubscriptExpr(LLoc: lbLoc, RLoc: rbLoc, Base: base, Args: ArgExprs);
5055	}
5056
5057	ExprResult Res =
5058	CreateBuiltinArraySubscriptExpr(Base: base, LLoc: lbLoc, Idx: ArgExprs.front(), RLoc: rbLoc);
5059
5060	if (!Res.isInvalid() && isa<ArraySubscriptExpr>(Val: Res.get()))
5061	CheckSubscriptAccessOfNoDeref(E: cast<ArraySubscriptExpr>(Val: Res.get()));
5062
5063	return Res;
5064	}
5065
5066	ExprResult Sema::tryConvertExprToType(Expr *E, QualType Ty) {
5067	InitializedEntity Entity = InitializedEntity::InitializeTemporary(Type: Ty);
5068	InitializationKind Kind =
5069	InitializationKind::CreateCopy(InitLoc: E->getBeginLoc(), EqualLoc: SourceLocation());
5070	InitializationSequence InitSeq(*this, Entity, Kind, E);
5071	return InitSeq.Perform(S&: *this, Entity, Kind, Args: E);
5072	}
5073
5074	ExprResult Sema::CreateBuiltinMatrixSubscriptExpr(Expr *Base, Expr *RowIdx,
5075	Expr *ColumnIdx,
5076	SourceLocation RBLoc) {
5077	ExprResult BaseR = CheckPlaceholderExpr(E: Base);
5078	if (BaseR.isInvalid())
5079	return BaseR;
5080	Base = BaseR.get();
5081
5082	ExprResult RowR = CheckPlaceholderExpr(E: RowIdx);
5083	if (RowR.isInvalid())
5084	return RowR;
5085	RowIdx = RowR.get();
5086
5087	if (!ColumnIdx)
5088	return new (Context) MatrixSubscriptExpr(
5089	Base, RowIdx, ColumnIdx, Context.IncompleteMatrixIdxTy, RBLoc);
5090
5091	// Build an unanalyzed expression if any of the operands is type-dependent.
5092	if (Base->isTypeDependent() || RowIdx->isTypeDependent() ||
5093	ColumnIdx->isTypeDependent())
5094	return new (Context) MatrixSubscriptExpr(Base, RowIdx, ColumnIdx,
5095	Context.DependentTy, RBLoc);
5096
5097	ExprResult ColumnR = CheckPlaceholderExpr(E: ColumnIdx);
5098	if (ColumnR.isInvalid())
5099	return ColumnR;
5100	ColumnIdx = ColumnR.get();
5101
5102	// Check that IndexExpr is an integer expression. If it is a constant
5103	// expression, check that it is less than Dim (= the number of elements in the
5104	// corresponding dimension).
5105	auto IsIndexValid = [&](Expr *IndexExpr, unsigned Dim,
5106	bool IsColumnIdx) -> Expr * {
5107	if (!IndexExpr->getType()->isIntegerType() &&
5108	!IndexExpr->isTypeDependent()) {
5109	Diag(Loc: IndexExpr->getBeginLoc(), DiagID: diag::err_matrix_index_not_integer)
5110	<< IsColumnIdx;
5111	return nullptr;
5112	}
5113
5114	if (std::optional<llvm::APSInt> Idx =
5115	IndexExpr->getIntegerConstantExpr(Ctx: Context)) {
5116	if ((*Idx < 0 || *Idx >= Dim)) {
5117	Diag(Loc: IndexExpr->getBeginLoc(), DiagID: diag::err_matrix_index_outside_range)
5118	<< IsColumnIdx << Dim;
5119	return nullptr;
5120	}
5121	}
5122
5123	ExprResult ConvExpr = IndexExpr;
5124	assert(!ConvExpr.isInvalid() &&
5125	"should be able to convert any integer type to size type");
5126	return ConvExpr.get();
5127	};
5128
5129	auto *MTy = Base->getType()->getAs<ConstantMatrixType>();
5130	RowIdx = IsIndexValid(RowIdx, MTy->getNumRows(), false);
5131	ColumnIdx = IsIndexValid(ColumnIdx, MTy->getNumColumns(), true);
5132	if (!RowIdx || !ColumnIdx)
5133	return ExprError();
5134
5135	return new (Context) MatrixSubscriptExpr(Base, RowIdx, ColumnIdx,
5136	MTy->getElementType(), RBLoc);
5137	}
5138
5139	void Sema::CheckAddressOfNoDeref(const Expr *E) {
5140	ExpressionEvaluationContextRecord &LastRecord = ExprEvalContexts.back();
5141	const Expr *StrippedExpr = E->IgnoreParenImpCasts();
5142
5143	// For expressions like `&(*s).b`, the base is recorded and what should be
5144	// checked.
5145	const MemberExpr *Member = nullptr;
5146	while ((Member = dyn_cast<MemberExpr>(Val: StrippedExpr)) && !Member->isArrow())
5147	StrippedExpr = Member->getBase()->IgnoreParenImpCasts();
5148
5149	LastRecord.PossibleDerefs.erase(Ptr: StrippedExpr);
5150	}
5151
5152	void Sema::CheckSubscriptAccessOfNoDeref(const ArraySubscriptExpr *E) {
5153	if (isUnevaluatedContext())
5154	return;
5155
5156	QualType ResultTy = E->getType();
5157	ExpressionEvaluationContextRecord &LastRecord = ExprEvalContexts.back();
5158
5159	// Bail if the element is an array since it is not memory access.
5160	if (isa<ArrayType>(Val: ResultTy))
5161	return;
5162
5163	if (ResultTy->hasAttr(AK: attr::NoDeref)) {
5164	LastRecord.PossibleDerefs.insert(Ptr: E);
5165	return;
5166	}
5167
5168	// Check if the base type is a pointer to a member access of a struct
5169	// marked with noderef.
5170	const Expr *Base = E->getBase();
5171	QualType BaseTy = Base->getType();
5172	if (!(isa<ArrayType>(Val: BaseTy) || isa<PointerType>(Val: BaseTy)))
5173	// Not a pointer access
5174	return;
5175
5176	const MemberExpr *Member = nullptr;
5177	while ((Member = dyn_cast<MemberExpr>(Val: Base->IgnoreParenCasts())) &&
5178	Member->isArrow())
5179	Base = Member->getBase();
5180
5181	if (const auto *Ptr = dyn_cast<PointerType>(Val: Base->getType())) {
5182	if (Ptr->getPointeeType()->hasAttr(AK: attr::NoDeref))
5183	LastRecord.PossibleDerefs.insert(Ptr: E);
5184	}
5185	}
5186
5187	ExprResult
5188	Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc,
5189	Expr *Idx, SourceLocation RLoc) {
5190	Expr *LHSExp = Base;
5191	Expr *RHSExp = Idx;
5192
5193	ExprValueKind VK = VK_LValue;
5194	ExprObjectKind OK = OK_Ordinary;
5195
5196	// Per C++ core issue 1213, the result is an xvalue if either operand is
5197	// a non-lvalue array, and an lvalue otherwise.
5198	if (getLangOpts().CPlusPlus11) {
5199	for (auto *Op : {LHSExp, RHSExp}) {
5200	Op = Op->IgnoreImplicit();
5201	if (Op->getType()->isArrayType() && !Op->isLValue())
5202	VK = VK_XValue;
5203	}
5204	}
5205
5206	// Perform default conversions.
5207	if (!LHSExp->getType()->isSubscriptableVectorType()) {
5208	ExprResult Result = DefaultFunctionArrayLvalueConversion(E: LHSExp);
5209	if (Result.isInvalid())
5210	return ExprError();
5211	LHSExp = Result.get();
5212	}
5213	ExprResult Result = DefaultFunctionArrayLvalueConversion(E: RHSExp);
5214	if (Result.isInvalid())
5215	return ExprError();
5216	RHSExp = Result.get();
5217
5218	QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType();
5219
5220	// C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent
5221	// to the expression *((e1)+(e2)). This means the array "Base" may actually be
5222	// in the subscript position. As a result, we need to derive the array base
5223	// and index from the expression types.
5224	Expr *BaseExpr, *IndexExpr;
5225	QualType ResultType;
5226	if (LHSTy->isDependentType() || RHSTy->isDependentType()) {
5227	BaseExpr = LHSExp;
5228	IndexExpr = RHSExp;
5229	ResultType =
5230	getDependentArraySubscriptType(LHS: LHSExp, RHS: RHSExp, Ctx: getASTContext());
5231	} else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) {
5232	BaseExpr = LHSExp;
5233	IndexExpr = RHSExp;
5234	ResultType = PTy->getPointeeType();
5235	} else if (const ObjCObjectPointerType *PTy =
5236	LHSTy->getAs<ObjCObjectPointerType>()) {
5237	BaseExpr = LHSExp;
5238	IndexExpr = RHSExp;
5239
5240	// Use custom logic if this should be the pseudo-object subscript
5241	// expression.
5242	if (!LangOpts.isSubscriptPointerArithmetic())
5243	return ObjC().BuildObjCSubscriptExpression(RB: RLoc, BaseExpr, IndexExpr,
5244	getterMethod: nullptr, setterMethod: nullptr);
5245
5246	ResultType = PTy->getPointeeType();
5247	} else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) {
5248	// Handle the uncommon case of "123[Ptr]".
5249	BaseExpr = RHSExp;
5250	IndexExpr = LHSExp;
5251	ResultType = PTy->getPointeeType();
5252	} else if (const ObjCObjectPointerType *PTy =
5253	RHSTy->getAs<ObjCObjectPointerType>()) {
5254	// Handle the uncommon case of "123[Ptr]".
5255	BaseExpr = RHSExp;
5256	IndexExpr = LHSExp;
5257	ResultType = PTy->getPointeeType();
5258	if (!LangOpts.isSubscriptPointerArithmetic()) {
5259	Diag(Loc: LLoc, DiagID: diag::err_subscript_nonfragile_interface)
5260	<< ResultType << BaseExpr->getSourceRange();
5261	return ExprError();
5262	}
5263	} else if (LHSTy->isSubscriptableVectorType()) {
5264	if (LHSTy->isBuiltinType() &&
5265	LHSTy->getAs<BuiltinType>()->isSveVLSBuiltinType()) {
5266	const BuiltinType *BTy = LHSTy->getAs<BuiltinType>();
5267	if (BTy->isSVEBool())
5268	return ExprError(Diag(Loc: LLoc, DiagID: diag::err_subscript_svbool_t)
5269	<< LHSExp->getSourceRange()
5270	<< RHSExp->getSourceRange());
5271	ResultType = BTy->getSveEltType(Ctx: Context);
5272	} else {
5273	const VectorType *VTy = LHSTy->getAs<VectorType>();
5274	ResultType = VTy->getElementType();
5275	}
5276	BaseExpr = LHSExp; // vectors: V[123]
5277	IndexExpr = RHSExp;
5278	// We apply C++ DR1213 to vector subscripting too.
5279	if (getLangOpts().CPlusPlus11 && LHSExp->isPRValue()) {
5280	ExprResult Materialized = TemporaryMaterializationConversion(E: LHSExp);
5281	if (Materialized.isInvalid())
5282	return ExprError();
5283	LHSExp = Materialized.get();
5284	}
5285	VK = LHSExp->getValueKind();
5286	if (VK != VK_PRValue)
5287	OK = OK_VectorComponent;
5288
5289	QualType BaseType = BaseExpr->getType();
5290	Qualifiers BaseQuals = BaseType.getQualifiers();
5291	Qualifiers MemberQuals = ResultType.getQualifiers();
5292	Qualifiers Combined = BaseQuals + MemberQuals;
5293	if (Combined != MemberQuals)
5294	ResultType = Context.getQualifiedType(T: ResultType, Qs: Combined);
5295	} else if (LHSTy->isArrayType()) {
5296	// If we see an array that wasn't promoted by
5297	// DefaultFunctionArrayLvalueConversion, it must be an array that
5298	// wasn't promoted because of the C90 rule that doesn't
5299	// allow promoting non-lvalue arrays. Warn, then
5300	// force the promotion here.
5301	Diag(Loc: LHSExp->getBeginLoc(), DiagID: diag::ext_subscript_non_lvalue)
5302	<< LHSExp->getSourceRange();
5303	LHSExp = ImpCastExprToType(E: LHSExp, Type: Context.getArrayDecayedType(T: LHSTy),
5304	CK: CK_ArrayToPointerDecay).get();
5305	LHSTy = LHSExp->getType();
5306
5307	BaseExpr = LHSExp;
5308	IndexExpr = RHSExp;
5309	ResultType = LHSTy->castAs<PointerType>()->getPointeeType();
5310	} else if (RHSTy->isArrayType()) {
5311	// Same as previous, except for 123[f().a] case
5312	Diag(Loc: RHSExp->getBeginLoc(), DiagID: diag::ext_subscript_non_lvalue)
5313	<< RHSExp->getSourceRange();
5314	RHSExp = ImpCastExprToType(E: RHSExp, Type: Context.getArrayDecayedType(T: RHSTy),
5315	CK: CK_ArrayToPointerDecay).get();
5316	RHSTy = RHSExp->getType();
5317
5318	BaseExpr = RHSExp;
5319	IndexExpr = LHSExp;
5320	ResultType = RHSTy->castAs<PointerType>()->getPointeeType();
5321	} else {
5322	return ExprError(Diag(Loc: LLoc, DiagID: diag::err_typecheck_subscript_value)
5323	<< LHSExp->getSourceRange() << RHSExp->getSourceRange());
5324	}
5325	// C99 6.5.2.1p1
5326	if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent())
5327	return ExprError(Diag(Loc: LLoc, DiagID: diag::err_typecheck_subscript_not_integer)
5328	<< IndexExpr->getSourceRange());
5329
5330	if ((IndexExpr->getType()->isSpecificBuiltinType(K: BuiltinType::Char_S) ||
5331	IndexExpr->getType()->isSpecificBuiltinType(K: BuiltinType::Char_U)) &&
5332	!IndexExpr->isTypeDependent()) {
5333	std::optional<llvm::APSInt> IntegerContantExpr =
5334	IndexExpr->getIntegerConstantExpr(Ctx: getASTContext());
5335	if (!IntegerContantExpr.has_value() ||
5336	IntegerContantExpr.value().isNegative())
5337	Diag(Loc: LLoc, DiagID: diag::warn_subscript_is_char) << IndexExpr->getSourceRange();
5338	}
5339
5340	// C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly,
5341	// C++ [expr.sub]p1: The type "T" shall be a completely-defined object
5342	// type. Note that Functions are not objects, and that (in C99 parlance)
5343	// incomplete types are not object types.
5344	if (ResultType->isFunctionType()) {
5345	Diag(Loc: BaseExpr->getBeginLoc(), DiagID: diag::err_subscript_function_type)
5346	<< ResultType << BaseExpr->getSourceRange();
5347	return ExprError();
5348	}
5349
5350	if (ResultType->isVoidType() && !getLangOpts().CPlusPlus) {
5351	// GNU extension: subscripting on pointer to void
5352	Diag(Loc: LLoc, DiagID: diag::ext_gnu_subscript_void_type)
5353	<< BaseExpr->getSourceRange();
5354
5355	// C forbids expressions of unqualified void type from being l-values.
5356	// See IsCForbiddenLValueType.
5357	if (!ResultType.hasQualifiers())
5358	VK = VK_PRValue;
5359	} else if (!ResultType->isDependentType() &&
5360	!ResultType.isWebAssemblyReferenceType() &&
5361	RequireCompleteSizedType(
5362	Loc: LLoc, T: ResultType,
5363	DiagID: diag::err_subscript_incomplete_or_sizeless_type, Args: BaseExpr))
5364	return ExprError();
5365
5366	assert(VK == VK_PRValue || LangOpts.CPlusPlus ||
5367	!ResultType.isCForbiddenLValueType());
5368
5369	if (LHSExp->IgnoreParenImpCasts()->getType()->isVariablyModifiedType() &&
5370	FunctionScopes.size() > 1) {
5371	if (auto *TT =
5372	LHSExp->IgnoreParenImpCasts()->getType()->getAs<TypedefType>()) {
5373	for (auto I = FunctionScopes.rbegin(),
5374	E = std::prev(x: FunctionScopes.rend());
5375	I != E; ++I) {
5376	auto *CSI = dyn_cast<CapturingScopeInfo>(Val: *I);
5377	if (CSI == nullptr)
5378	break;
5379	DeclContext *DC = nullptr;
5380	if (auto *LSI = dyn_cast<LambdaScopeInfo>(Val: CSI))
5381	DC = LSI->CallOperator;
5382	else if (auto *CRSI = dyn_cast<CapturedRegionScopeInfo>(Val: CSI))
5383	DC = CRSI->TheCapturedDecl;
5384	else if (auto *BSI = dyn_cast<BlockScopeInfo>(Val: CSI))
5385	DC = BSI->TheDecl;
5386	if (DC) {
5387	if (DC->containsDecl(D: TT->getDecl()))
5388	break;
5389	captureVariablyModifiedType(
5390	Context, T: LHSExp->IgnoreParenImpCasts()->getType(), CSI);
5391	}
5392	}
5393	}
5394	}
5395
5396	return new (Context)
5397	ArraySubscriptExpr(LHSExp, RHSExp, ResultType, VK, OK, RLoc);
5398	}
5399
5400	bool Sema::CheckCXXDefaultArgExpr(SourceLocation CallLoc, FunctionDecl *FD,
5401	ParmVarDecl *Param, Expr *RewrittenInit,
5402	bool SkipImmediateInvocations) {
5403	if (Param->hasUnparsedDefaultArg()) {
5404	assert(!RewrittenInit && "Should not have a rewritten init expression yet");
5405	// If we've already cleared out the location for the default argument,
5406	// that means we're parsing it right now.
5407	if (!UnparsedDefaultArgLocs.count(Val: Param)) {
5408	Diag(Loc: Param->getBeginLoc(), DiagID: diag::err_recursive_default_argument) << FD;
5409	Diag(Loc: CallLoc, DiagID: diag::note_recursive_default_argument_used_here);
5410	Param->setInvalidDecl();
5411	return true;
5412	}
5413
5414	Diag(Loc: CallLoc, DiagID: diag::err_use_of_default_argument_to_function_declared_later)
5415	<< FD << cast<CXXRecordDecl>(Val: FD->getDeclContext());
5416	Diag(Loc: UnparsedDefaultArgLocs[Param],
5417	DiagID: diag::note_default_argument_declared_here);
5418	return true;
5419	}
5420
5421	if (Param->hasUninstantiatedDefaultArg()) {
5422	assert(!RewrittenInit && "Should not have a rewitten init expression yet");
5423	if (InstantiateDefaultArgument(CallLoc, FD, Param))
5424	return true;
5425	}
5426
5427	Expr *Init = RewrittenInit ? RewrittenInit : Param->getInit();
5428	assert(Init && "default argument but no initializer?");
5429
5430	// If the default expression creates temporaries, we need to
5431	// push them to the current stack of expression temporaries so they'll
5432	// be properly destroyed.
5433	// FIXME: We should really be rebuilding the default argument with new
5434	// bound temporaries; see the comment in PR5810.
5435	// We don't need to do that with block decls, though, because
5436	// blocks in default argument expression can never capture anything.
5437	if (auto *InitWithCleanup = dyn_cast<ExprWithCleanups>(Val: Init)) {
5438	// Set the "needs cleanups" bit regardless of whether there are
5439	// any explicit objects.
5440	Cleanup.setExprNeedsCleanups(InitWithCleanup->cleanupsHaveSideEffects());
5441	// Append all the objects to the cleanup list. Right now, this
5442	// should always be a no-op, because blocks in default argument
5443	// expressions should never be able to capture anything.
5444	assert(!InitWithCleanup->getNumObjects() &&
5445	"default argument expression has capturing blocks?");
5446	}
5447	// C++ [expr.const]p15.1:
5448	// An expression or conversion is in an immediate function context if it is
5449	// potentially evaluated and [...] its innermost enclosing non-block scope
5450	// is a function parameter scope of an immediate function.
5451	EnterExpressionEvaluationContext EvalContext(
5452	*this,
5453	FD->isImmediateFunction()
5454	? ExpressionEvaluationContext::ImmediateFunctionContext
5455	: ExpressionEvaluationContext::PotentiallyEvaluated,
5456	Param);
5457	ExprEvalContexts.back().IsCurrentlyCheckingDefaultArgumentOrInitializer =
5458	SkipImmediateInvocations;
5459	runWithSufficientStackSpace(Loc: CallLoc, Fn: [&] {
5460	MarkDeclarationsReferencedInExpr(E: Init, /*SkipLocalVariables=*/true);
5461	});
5462	return false;
5463	}
5464
5465	struct ImmediateCallVisitor : DynamicRecursiveASTVisitor {
5466	const ASTContext &Context;
5467	ImmediateCallVisitor(const ASTContext &Ctx) : Context(Ctx) {
5468	ShouldVisitImplicitCode = true;
5469	}
5470
5471	bool HasImmediateCalls = false;
5472
5473	bool VisitCallExpr(CallExpr *E) override {
5474	if (const FunctionDecl *FD = E->getDirectCallee())
5475	HasImmediateCalls |= FD->isImmediateFunction();
5476	return DynamicRecursiveASTVisitor::VisitStmt(S: E);
5477	}
5478
5479	bool VisitCXXConstructExpr(CXXConstructExpr *E) override {
5480	if (const FunctionDecl *FD = E->getConstructor())
5481	HasImmediateCalls |= FD->isImmediateFunction();
5482	return DynamicRecursiveASTVisitor::VisitStmt(S: E);
5483	}
5484
5485	// SourceLocExpr are not immediate invocations
5486	// but CXXDefaultInitExpr/CXXDefaultArgExpr containing a SourceLocExpr
5487	// need to be rebuilt so that they refer to the correct SourceLocation and
5488	// DeclContext.
5489	bool VisitSourceLocExpr(SourceLocExpr *E) override {
5490	HasImmediateCalls = true;
5491	return DynamicRecursiveASTVisitor::VisitStmt(S: E);
5492	}
5493
5494	// A nested lambda might have parameters with immediate invocations
5495	// in their default arguments.
5496	// The compound statement is not visited (as it does not constitute a
5497	// subexpression).
5498	// FIXME: We should consider visiting and transforming captures
5499	// with init expressions.
5500	bool VisitLambdaExpr(LambdaExpr *E) override {
5501	return VisitCXXMethodDecl(D: E->getCallOperator());
5502	}
5503
5504	bool VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) override {
5505	return TraverseStmt(S: E->getExpr());
5506	}
5507
5508	bool VisitCXXDefaultInitExpr(CXXDefaultInitExpr *E) override {
5509	return TraverseStmt(S: E->getExpr());
5510	}
5511	};
5512
5513	struct EnsureImmediateInvocationInDefaultArgs
5514	: TreeTransform<EnsureImmediateInvocationInDefaultArgs> {
5515	EnsureImmediateInvocationInDefaultArgs(Sema &SemaRef)
5516	: TreeTransform(SemaRef) {}
5517
5518	bool AlwaysRebuild() { return true; }
5519
5520	// Lambda can only have immediate invocations in the default
5521	// args of their parameters, which is transformed upon calling the closure.
5522	// The body is not a subexpression, so we have nothing to do.
5523	// FIXME: Immediate calls in capture initializers should be transformed.
5524	ExprResult TransformLambdaExpr(LambdaExpr *E) { return E; }
5525	ExprResult TransformBlockExpr(BlockExpr *E) { return E; }
5526
5527	// Make sure we don't rebuild the this pointer as it would
5528	// cause it to incorrectly point it to the outermost class
5529	// in the case of nested struct initialization.
5530	ExprResult TransformCXXThisExpr(CXXThisExpr *E) { return E; }
5531
5532	// Rewrite to source location to refer to the context in which they are used.
5533	ExprResult TransformSourceLocExpr(SourceLocExpr *E) {
5534	DeclContext *DC = E->getParentContext();
5535	if (DC == SemaRef.CurContext)
5536	return E;
5537
5538	// FIXME: During instantiation, because the rebuild of defaults arguments
5539	// is not always done in the context of the template instantiator,
5540	// we run the risk of producing a dependent source location
5541	// that would never be rebuilt.
5542	// This usually happens during overload resolution, or in contexts
5543	// where the value of the source location does not matter.
5544	// However, we should find a better way to deal with source location
5545	// of function templates.
5546	if (!SemaRef.CurrentInstantiationScope ||
5547	!SemaRef.CurContext->isDependentContext() || DC->isDependentContext())
5548	DC = SemaRef.CurContext;
5549
5550	return getDerived().RebuildSourceLocExpr(
5551	Kind: E->getIdentKind(), ResultTy: E->getType(), BuiltinLoc: E->getBeginLoc(), RPLoc: E->getEndLoc(), ParentContext: DC);
5552	}
5553	};
5554
5555	ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc,
5556	FunctionDecl *FD, ParmVarDecl *Param,
5557	Expr *Init) {
5558	assert(Param->hasDefaultArg() && "can't build nonexistent default arg");
5559
5560	bool NestedDefaultChecking = isCheckingDefaultArgumentOrInitializer();
5561	bool NeedRebuild = needsRebuildOfDefaultArgOrInit();
5562	std::optional<ExpressionEvaluationContextRecord::InitializationContext>
5563	InitializationContext =
5564	OutermostDeclarationWithDelayedImmediateInvocations();
5565	if (!InitializationContext.has_value())
5566	InitializationContext.emplace(args&: CallLoc, args&: Param, args&: CurContext);
5567
5568	if (!Init && !Param->hasUnparsedDefaultArg()) {
5569	// Mark that we are replacing a default argument first.
5570	// If we are instantiating a template we won't have to
5571	// retransform immediate calls.
5572	// C++ [expr.const]p15.1:
5573	// An expression or conversion is in an immediate function context if it
5574	// is potentially evaluated and [...] its innermost enclosing non-block
5575	// scope is a function parameter scope of an immediate function.
5576	EnterExpressionEvaluationContext EvalContext(
5577	*this,
5578	FD->isImmediateFunction()
5579	? ExpressionEvaluationContext::ImmediateFunctionContext
5580	: ExpressionEvaluationContext::PotentiallyEvaluated,
5581	Param);
5582
5583	if (Param->hasUninstantiatedDefaultArg()) {
5584	if (InstantiateDefaultArgument(CallLoc, FD, Param))
5585	return ExprError();
5586	}
5587	// CWG2631
5588	// An immediate invocation that is not evaluated where it appears is
5589	// evaluated and checked for whether it is a constant expression at the
5590	// point where the enclosing initializer is used in a function call.
5591	ImmediateCallVisitor V(getASTContext());
5592	if (!NestedDefaultChecking)
5593	V.TraverseDecl(D: Param);
5594
5595	// Rewrite the call argument that was created from the corresponding
5596	// parameter's default argument.
5597	if (V.HasImmediateCalls ||
5598	(NeedRebuild && isa_and_present<ExprWithCleanups>(Val: Param->getInit()))) {
5599	if (V.HasImmediateCalls)
5600	ExprEvalContexts.back().DelayedDefaultInitializationContext = {
5601	CallLoc, Param, CurContext};
5602	// Pass down lifetime extending flag, and collect temporaries in
5603	// CreateMaterializeTemporaryExpr when we rewrite the call argument.
5604	currentEvaluationContext().InLifetimeExtendingContext =
5605	parentEvaluationContext().InLifetimeExtendingContext;
5606	EnsureImmediateInvocationInDefaultArgs Immediate(*this);
5607	ExprResult Res;
5608	runWithSufficientStackSpace(Loc: CallLoc, Fn: [&] {
5609	Res = Immediate.TransformInitializer(Init: Param->getInit(),
5610	/*NotCopy=*/NotCopyInit: false);
5611	});
5612	if (Res.isInvalid())
5613	return ExprError();
5614	Res = ConvertParamDefaultArgument(Param, DefaultArg: Res.get(),
5615	EqualLoc: Res.get()->getBeginLoc());
5616	if (Res.isInvalid())
5617	return ExprError();
5618	Init = Res.get();
5619	}
5620	}
5621
5622	if (CheckCXXDefaultArgExpr(
5623	CallLoc, FD, Param, RewrittenInit: Init,
5624	/*SkipImmediateInvocations=*/NestedDefaultChecking))
5625	return ExprError();
5626
5627	return CXXDefaultArgExpr::Create(C: Context, Loc: InitializationContext->Loc, Param,
5628	RewrittenExpr: Init, UsedContext: InitializationContext->Context);
5629	}
5630
5631	static FieldDecl *FindFieldDeclInstantiationPattern(const ASTContext &Ctx,
5632	FieldDecl *Field) {
5633	if (FieldDecl *Pattern = Ctx.getInstantiatedFromUnnamedFieldDecl(Field))
5634	return Pattern;
5635	auto *ParentRD = cast<CXXRecordDecl>(Val: Field->getParent());
5636	CXXRecordDecl *ClassPattern = ParentRD->getTemplateInstantiationPattern();
5637	DeclContext::lookup_result Lookup =
5638	ClassPattern->lookup(Name: Field->getDeclName());
5639	auto Rng = llvm::make_filter_range(
5640	Range&: Lookup, Pred: [](auto &&L) { return isa<FieldDecl>(*L); });
5641	if (Rng.empty())
5642	return nullptr;
5643	// FIXME: this breaks clang/test/Modules/pr28812.cpp
5644	// assert(std::distance(Rng.begin(), Rng.end()) <= 1
5645	// && "Duplicated instantiation pattern for field decl");
5646	return cast<FieldDecl>(Val: *Rng.begin());
5647	}
5648
5649	ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
5650	assert(Field->hasInClassInitializer());
5651
5652	CXXThisScopeRAII This(*this, Field->getParent(), Qualifiers());
5653
5654	auto *ParentRD = cast<CXXRecordDecl>(Val: Field->getParent());
5655
5656	std::optional<ExpressionEvaluationContextRecord::InitializationContext>
5657	InitializationContext =
5658	OutermostDeclarationWithDelayedImmediateInvocations();
5659	if (!InitializationContext.has_value())
5660	InitializationContext.emplace(args&: Loc, args&: Field, args&: CurContext);
5661
5662	Expr *Init = nullptr;
5663
5664	bool NestedDefaultChecking = isCheckingDefaultArgumentOrInitializer();
5665	bool NeedRebuild = needsRebuildOfDefaultArgOrInit();
5666	EnterExpressionEvaluationContext EvalContext(
5667	*this, ExpressionEvaluationContext::PotentiallyEvaluated, Field);
5668
5669	if (!Field->getInClassInitializer()) {
5670	// Maybe we haven't instantiated the in-class initializer. Go check the
5671	// pattern FieldDecl to see if it has one.
5672	if (isTemplateInstantiation(Kind: ParentRD->getTemplateSpecializationKind())) {
5673	FieldDecl *Pattern =
5674	FindFieldDeclInstantiationPattern(Ctx: getASTContext(), Field);
5675	assert(Pattern && "We must have set the Pattern!");
5676	if (!Pattern->hasInClassInitializer() ||
5677	InstantiateInClassInitializer(PointOfInstantiation: Loc, Instantiation: Field, Pattern,
5678	TemplateArgs: getTemplateInstantiationArgs(D: Field))) {
5679	Field->setInvalidDecl();
5680	return ExprError();
5681	}
5682	}
5683	}
5684
5685	// CWG2631
5686	// An immediate invocation that is not evaluated where it appears is
5687	// evaluated and checked for whether it is a constant expression at the
5688	// point where the enclosing initializer is used in a [...] a constructor
5689	// definition, or an aggregate initialization.
5690	ImmediateCallVisitor V(getASTContext());
5691	if (!NestedDefaultChecking)
5692	V.TraverseDecl(D: Field);
5693
5694	// CWG1815
5695	// Support lifetime extension of temporary created by aggregate
5696	// initialization using a default member initializer. We should rebuild
5697	// the initializer in a lifetime extension context if the initializer
5698	// expression is an ExprWithCleanups. Then make sure the normal lifetime
5699	// extension code recurses into the default initializer and does lifetime
5700	// extension when warranted.
5701	bool ContainsAnyTemporaries =
5702	isa_and_present<ExprWithCleanups>(Val: Field->getInClassInitializer());
5703	if (Field->getInClassInitializer() &&
5704	!Field->getInClassInitializer()->containsErrors() &&
5705	(V.HasImmediateCalls || (NeedRebuild && ContainsAnyTemporaries))) {
5706	ExprEvalContexts.back().DelayedDefaultInitializationContext = {Loc, Field,
5707	CurContext};
5708	ExprEvalContexts.back().IsCurrentlyCheckingDefaultArgumentOrInitializer =
5709	NestedDefaultChecking;
5710	// Pass down lifetime extending flag, and collect temporaries in
5711	// CreateMaterializeTemporaryExpr when we rewrite the call argument.
5712	currentEvaluationContext().InLifetimeExtendingContext =
5713	parentEvaluationContext().InLifetimeExtendingContext;
5714	EnsureImmediateInvocationInDefaultArgs Immediate(*this);
5715	ExprResult Res;
5716	runWithSufficientStackSpace(Loc, Fn: [&] {
5717	Res = Immediate.TransformInitializer(Init: Field->getInClassInitializer(),
5718	/*CXXDirectInit=*/NotCopyInit: false);
5719	});
5720	if (!Res.isInvalid())
5721	Res = ConvertMemberDefaultInitExpression(FD: Field, InitExpr: Res.get(), InitLoc: Loc);
5722	if (Res.isInvalid()) {
5723	Field->setInvalidDecl();
5724	return ExprError();
5725	}
5726	Init = Res.get();
5727	}
5728
5729	if (Field->getInClassInitializer()) {
5730	Expr *E = Init ? Init : Field->getInClassInitializer();
5731	if (!NestedDefaultChecking)
5732	runWithSufficientStackSpace(Loc, Fn: [&] {
5733	MarkDeclarationsReferencedInExpr(E, /*SkipLocalVariables=*/false);
5734	});
5735	if (isInLifetimeExtendingContext())
5736	DiscardCleanupsInEvaluationContext();
5737	// C++11 [class.base.init]p7:
5738	// The initialization of each base and member constitutes a
5739	// full-expression.
5740	ExprResult Res = ActOnFinishFullExpr(Expr: E, /*DiscardedValue=*/false);
5741	if (Res.isInvalid()) {
5742	Field->setInvalidDecl();
5743	return ExprError();
5744	}
5745	Init = Res.get();
5746
5747	return CXXDefaultInitExpr::Create(Ctx: Context, Loc: InitializationContext->Loc,
5748	Field, UsedContext: InitializationContext->Context,
5749	RewrittenInitExpr: Init);
5750	}
5751
5752	// DR1351:
5753	// If the brace-or-equal-initializer of a non-static data member
5754	// invokes a defaulted default constructor of its class or of an
5755	// enclosing class in a potentially evaluated subexpression, the
5756	// program is ill-formed.
5757	//
5758	// This resolution is unworkable: the exception specification of the
5759	// default constructor can be needed in an unevaluated context, in
5760	// particular, in the operand of a noexcept-expression, and we can be
5761	// unable to compute an exception specification for an enclosed class.
5762	//
5763	// Any attempt to resolve the exception specification of a defaulted default
5764	// constructor before the initializer is lexically complete will ultimately
5765	// come here at which point we can diagnose it.
5766	RecordDecl *OutermostClass = ParentRD->getOuterLexicalRecordContext();
5767	Diag(Loc, DiagID: diag::err_default_member_initializer_not_yet_parsed)
5768	<< OutermostClass << Field;
5769	Diag(Loc: Field->getEndLoc(),
5770	DiagID: diag::note_default_member_initializer_not_yet_parsed);
5771	// Recover by marking the field invalid, unless we're in a SFINAE context.
5772	if (!isSFINAEContext())
5773	Field->setInvalidDecl();
5774	return ExprError();
5775	}
5776
5777	VariadicCallType Sema::getVariadicCallType(FunctionDecl *FDecl,
5778	const FunctionProtoType *Proto,
5779	Expr *Fn) {
5780	if (Proto && Proto->isVariadic()) {
5781	if (isa_and_nonnull<CXXConstructorDecl>(Val: FDecl))
5782	return VariadicCallType::Constructor;
5783	else if (Fn && Fn->getType()->isBlockPointerType())
5784	return VariadicCallType::Block;
5785	else if (FDecl) {
5786	if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(Val: FDecl))
5787	if (Method->isInstance())
5788	return VariadicCallType::Method;
5789	} else if (Fn && Fn->getType() == Context.BoundMemberTy)
5790	return VariadicCallType::Method;
5791	return VariadicCallType::Function;
5792	}
5793	return VariadicCallType::DoesNotApply;
5794	}
5795
5796	namespace {
5797	class FunctionCallCCC final : public FunctionCallFilterCCC {
5798	public:
5799	FunctionCallCCC(Sema &SemaRef, const IdentifierInfo *FuncName,
5800	unsigned NumArgs, MemberExpr *ME)
5801	: FunctionCallFilterCCC(SemaRef, NumArgs, false, ME),
5802	FunctionName(FuncName) {}
5803
5804	bool ValidateCandidate(const TypoCorrection &candidate) override {
5805	if (!candidate.getCorrectionSpecifier() ||
5806	candidate.getCorrectionAsIdentifierInfo() != FunctionName) {
5807	return false;
5808	}
5809
5810	return FunctionCallFilterCCC::ValidateCandidate(candidate);
5811	}
5812
5813	std::unique_ptr<CorrectionCandidateCallback> clone() override {
5814	return std::make_unique<FunctionCallCCC>(args&: *this);
5815	}
5816
5817	private:
5818	const IdentifierInfo *const FunctionName;
5819	};
5820	}
5821
5822	static TypoCorrection TryTypoCorrectionForCall(Sema &S, Expr *Fn,
5823	FunctionDecl *FDecl,
5824	ArrayRef<Expr *> Args) {
5825	MemberExpr *ME = dyn_cast<MemberExpr>(Val: Fn);
5826	DeclarationName FuncName = FDecl->getDeclName();
5827	SourceLocation NameLoc = ME ? ME->getMemberLoc() : Fn->getBeginLoc();
5828
5829	FunctionCallCCC CCC(S, FuncName.getAsIdentifierInfo(), Args.size(), ME);
5830	if (TypoCorrection Corrected = S.CorrectTypo(
5831	Typo: DeclarationNameInfo(FuncName, NameLoc), LookupKind: Sema::LookupOrdinaryName,
5832	S: S.getScopeForContext(Ctx: S.CurContext), SS: nullptr, CCC,
5833	Mode: CorrectTypoKind::ErrorRecovery)) {
5834	if (NamedDecl *ND = Corrected.getFoundDecl()) {
5835	if (Corrected.isOverloaded()) {
5836	OverloadCandidateSet OCS(NameLoc, OverloadCandidateSet::CSK_Normal);
5837	OverloadCandidateSet::iterator Best;
5838	for (NamedDecl *CD : Corrected) {
5839	if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Val: CD))
5840	S.AddOverloadCandidate(Function: FD, FoundDecl: DeclAccessPair::make(D: FD, AS: AS_none), Args,
5841	CandidateSet&: OCS);
5842	}
5843	switch (OCS.BestViableFunction(S, Loc: NameLoc, Best)) {
5844	case OR_Success:
5845	ND = Best->FoundDecl;
5846	Corrected.setCorrectionDecl(ND);
5847	break;
5848	default:
5849	break;
5850	}
5851	}
5852	ND = ND->getUnderlyingDecl();
5853	if (isa<ValueDecl>(Val: ND) || isa<FunctionTemplateDecl>(Val: ND))
5854	return Corrected;
5855	}
5856	}
5857	return TypoCorrection();
5858	}
5859
5860	// [C++26][[expr.unary.op]/p4
5861	// A pointer to member is only formed when an explicit &
5862	// is used and its operand is a qualified-id not enclosed in parentheses.
5863	static bool isParenthetizedAndQualifiedAddressOfExpr(Expr *Fn) {
5864	if (!isa<ParenExpr>(Val: Fn))
5865	return false;
5866
5867	Fn = Fn->IgnoreParens();
5868
5869	auto *UO = dyn_cast<UnaryOperator>(Val: Fn);
5870	if (!UO || UO->getOpcode() != clang::UO_AddrOf)
5871	return false;
5872	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: UO->getSubExpr()->IgnoreParens())) {
5873	return DRE->hasQualifier();
5874	}
5875	if (auto *OVL = dyn_cast<OverloadExpr>(Val: UO->getSubExpr()->IgnoreParens()))
5876	return OVL->getQualifier();
5877	return false;
5878	}
5879
5880	bool
5881	Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn,
5882	FunctionDecl *FDecl,
5883	const FunctionProtoType *Proto,
5884	ArrayRef<Expr *> Args,
5885	SourceLocation RParenLoc,
5886	bool IsExecConfig) {
5887	// Bail out early if calling a builtin with custom typechecking.
5888	if (FDecl)
5889	if (unsigned ID = FDecl->getBuiltinID())
5890	if (Context.BuiltinInfo.hasCustomTypechecking(ID))
5891	return false;
5892
5893	// C99 6.5.2.2p7 - the arguments are implicitly converted, as if by
5894	// assignment, to the types of the corresponding parameter, ...
5895
5896	bool AddressOf = isParenthetizedAndQualifiedAddressOfExpr(Fn);
5897	bool HasExplicitObjectParameter =
5898	!AddressOf && FDecl && FDecl->hasCXXExplicitFunctionObjectParameter();
5899	unsigned ExplicitObjectParameterOffset = HasExplicitObjectParameter ? 1 : 0;
5900	unsigned NumParams = Proto->getNumParams();
5901	bool Invalid = false;
5902	unsigned MinArgs = FDecl ? FDecl->getMinRequiredArguments() : NumParams;
5903	unsigned FnKind = Fn->getType()->isBlockPointerType()
5904	? 1 /* block */
5905	: (IsExecConfig ? 3 /* kernel function (exec config) */
5906	: 0 /* function */);
5907
5908	// If too few arguments are available (and we don't have default
5909	// arguments for the remaining parameters), don't make the call.
5910	if (Args.size() < NumParams) {
5911	if (Args.size() < MinArgs) {
5912	TypoCorrection TC;
5913	if (FDecl && (TC = TryTypoCorrectionForCall(S&: *this, Fn, FDecl, Args))) {
5914	unsigned diag_id =
5915	MinArgs == NumParams && !Proto->isVariadic()
5916	? diag::err_typecheck_call_too_few_args_suggest
5917	: diag::err_typecheck_call_too_few_args_at_least_suggest;
5918	diagnoseTypo(
5919	Correction: TC, TypoDiag: PDiag(DiagID: diag_id)
5920	<< FnKind << MinArgs - ExplicitObjectParameterOffset
5921	<< static_cast<unsigned>(Args.size()) -
5922	ExplicitObjectParameterOffset
5923	<< HasExplicitObjectParameter << TC.getCorrectionRange());
5924	} else if (MinArgs - ExplicitObjectParameterOffset == 1 && FDecl &&
5925	FDecl->getParamDecl(i: ExplicitObjectParameterOffset)
5926	->getDeclName())
5927	Diag(Loc: RParenLoc,
5928	DiagID: MinArgs == NumParams && !Proto->isVariadic()
5929	? diag::err_typecheck_call_too_few_args_one
5930	: diag::err_typecheck_call_too_few_args_at_least_one)
5931	<< FnKind << FDecl->getParamDecl(i: ExplicitObjectParameterOffset)
5932	<< HasExplicitObjectParameter << Fn->getSourceRange();
5933	else
5934	Diag(Loc: RParenLoc, DiagID: MinArgs == NumParams && !Proto->isVariadic()
5935	? diag::err_typecheck_call_too_few_args
5936	: diag::err_typecheck_call_too_few_args_at_least)
5937	<< FnKind << MinArgs - ExplicitObjectParameterOffset
5938	<< static_cast<unsigned>(Args.size()) -
5939	ExplicitObjectParameterOffset
5940	<< HasExplicitObjectParameter << Fn->getSourceRange();
5941
5942	// Emit the location of the prototype.
5943	if (!TC && FDecl && !FDecl->getBuiltinID() && !IsExecConfig)
5944	Diag(Loc: FDecl->getLocation(), DiagID: diag::note_callee_decl)
5945	<< FDecl << FDecl->getParametersSourceRange();
5946
5947	return true;
5948	}
5949	// We reserve space for the default arguments when we create
5950	// the call expression, before calling ConvertArgumentsForCall.
5951	assert((Call->getNumArgs() == NumParams) &&
5952	"We should have reserved space for the default arguments before!");
5953	}
5954
5955	// If too many are passed and not variadic, error on the extras and drop
5956	// them.
5957	if (Args.size() > NumParams) {
5958	if (!Proto->isVariadic()) {
5959	TypoCorrection TC;
5960	if (FDecl && (TC = TryTypoCorrectionForCall(S&: *this, Fn, FDecl, Args))) {
5961	unsigned diag_id =
5962	MinArgs == NumParams && !Proto->isVariadic()
5963	? diag::err_typecheck_call_too_many_args_suggest
5964	: diag::err_typecheck_call_too_many_args_at_most_suggest;
5965	diagnoseTypo(
5966	Correction: TC, TypoDiag: PDiag(DiagID: diag_id)
5967	<< FnKind << NumParams - ExplicitObjectParameterOffset
5968	<< static_cast<unsigned>(Args.size()) -
5969	ExplicitObjectParameterOffset
5970	<< HasExplicitObjectParameter << TC.getCorrectionRange());
5971	} else if (NumParams - ExplicitObjectParameterOffset == 1 && FDecl &&
5972	FDecl->getParamDecl(i: ExplicitObjectParameterOffset)
5973	->getDeclName())
5974	Diag(Loc: Args[NumParams]->getBeginLoc(),
5975	DiagID: MinArgs == NumParams
5976	? diag::err_typecheck_call_too_many_args_one
5977	: diag::err_typecheck_call_too_many_args_at_most_one)
5978	<< FnKind << FDecl->getParamDecl(i: ExplicitObjectParameterOffset)
5979	<< static_cast<unsigned>(Args.size()) -
5980	ExplicitObjectParameterOffset
5981	<< HasExplicitObjectParameter << Fn->getSourceRange()
5982	<< SourceRange(Args[NumParams]->getBeginLoc(),
5983	Args.back()->getEndLoc());
5984	else
5985	Diag(Loc: Args[NumParams]->getBeginLoc(),
5986	DiagID: MinArgs == NumParams
5987	? diag::err_typecheck_call_too_many_args
5988	: diag::err_typecheck_call_too_many_args_at_most)
5989	<< FnKind << NumParams - ExplicitObjectParameterOffset
5990	<< static_cast<unsigned>(Args.size()) -
5991	ExplicitObjectParameterOffset
5992	<< HasExplicitObjectParameter << Fn->getSourceRange()
5993	<< SourceRange(Args[NumParams]->getBeginLoc(),
5994	Args.back()->getEndLoc());
5995
5996	// Emit the location of the prototype.
5997	if (!TC && FDecl && !FDecl->getBuiltinID() && !IsExecConfig)
5998	Diag(Loc: FDecl->getLocation(), DiagID: diag::note_callee_decl)
5999	<< FDecl << FDecl->getParametersSourceRange();
6000
6001	// This deletes the extra arguments.
6002	Call->shrinkNumArgs(NewNumArgs: NumParams);
6003	return true;
6004	}
6005	}
6006	SmallVector<Expr *, 8> AllArgs;
6007	VariadicCallType CallType = getVariadicCallType(FDecl, Proto, Fn);
6008
6009	Invalid = GatherArgumentsForCall(CallLoc: Call->getExprLoc(), FDecl, Proto, FirstParam: 0, Args,
6010	AllArgs, CallType);
6011	if (Invalid)
6012	return true;
6013	unsigned TotalNumArgs = AllArgs.size();
6014	for (unsigned i = 0; i < TotalNumArgs; ++i)
6015	Call->setArg(Arg: i, ArgExpr: AllArgs[i]);
6016
6017	Call->computeDependence();
6018	return false;
6019	}
6020
6021	bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, FunctionDecl *FDecl,
6022	const FunctionProtoType *Proto,
6023	unsigned FirstParam, ArrayRef<Expr *> Args,
6024	SmallVectorImpl<Expr *> &AllArgs,
6025	VariadicCallType CallType, bool AllowExplicit,
6026	bool IsListInitialization) {
6027	unsigned NumParams = Proto->getNumParams();
6028	bool Invalid = false;
6029	size_t ArgIx = 0;
6030	// Continue to check argument types (even if we have too few/many args).
6031	for (unsigned i = FirstParam; i < NumParams; i++) {
6032	QualType ProtoArgType = Proto->getParamType(i);
6033
6034	Expr *Arg;
6035	ParmVarDecl *Param = FDecl ? FDecl->getParamDecl(i) : nullptr;
6036	if (ArgIx < Args.size()) {
6037	Arg = Args[ArgIx++];
6038
6039	if (RequireCompleteType(Loc: Arg->getBeginLoc(), T: ProtoArgType,
6040	DiagID: diag::err_call_incomplete_argument, Args: Arg))
6041	return true;
6042
6043	// Strip the unbridged-cast placeholder expression off, if applicable.
6044	bool CFAudited = false;
6045	if (Arg->getType() == Context.ARCUnbridgedCastTy &&
6046	FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() &&
6047	(!Param || !Param->hasAttr<CFConsumedAttr>()))
6048	Arg = ObjC().stripARCUnbridgedCast(e: Arg);
6049	else if (getLangOpts().ObjCAutoRefCount &&
6050	FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() &&
6051	(!Param || !Param->hasAttr<CFConsumedAttr>()))
6052	CFAudited = true;
6053
6054	if (Proto->getExtParameterInfo(I: i).isNoEscape() &&
6055	ProtoArgType->isBlockPointerType())
6056	if (auto *BE = dyn_cast<BlockExpr>(Val: Arg->IgnoreParenNoopCasts(Ctx: Context)))
6057	BE->getBlockDecl()->setDoesNotEscape();
6058	if ((Proto->getExtParameterInfo(I: i).getABI() == ParameterABI::HLSLOut ||
6059	Proto->getExtParameterInfo(I: i).getABI() == ParameterABI::HLSLInOut)) {
6060	ExprResult ArgExpr = HLSL().ActOnOutParamExpr(Param, Arg);
6061	if (ArgExpr.isInvalid())
6062	return true;
6063	Arg = ArgExpr.getAs<Expr>();
6064	}
6065
6066	InitializedEntity Entity =
6067	Param ? InitializedEntity::InitializeParameter(Context, Parm: Param,
6068	Type: ProtoArgType)
6069	: InitializedEntity::InitializeParameter(
6070	Context, Type: ProtoArgType, Consumed: Proto->isParamConsumed(I: i));
6071
6072	// Remember that parameter belongs to a CF audited API.
6073	if (CFAudited)
6074	Entity.setParameterCFAudited();
6075
6076	ExprResult ArgE = PerformCopyInitialization(
6077	Entity, EqualLoc: SourceLocation(), Init: Arg, TopLevelOfInitList: IsListInitialization, AllowExplicit);
6078	if (ArgE.isInvalid())
6079	return true;
6080
6081	Arg = ArgE.getAs<Expr>();
6082	} else {
6083	assert(Param && "can't use default arguments without a known callee");
6084
6085	ExprResult ArgExpr = BuildCXXDefaultArgExpr(CallLoc, FD: FDecl, Param);
6086	if (ArgExpr.isInvalid())
6087	return true;
6088
6089	Arg = ArgExpr.getAs<Expr>();
6090	}
6091
6092	// Check for array bounds violations for each argument to the call. This
6093	// check only triggers warnings when the argument isn't a more complex Expr
6094	// with its own checking, such as a BinaryOperator.
6095	CheckArrayAccess(E: Arg);
6096
6097	// Check for violations of C99 static array rules (C99 6.7.5.3p7).
6098	CheckStaticArrayArgument(CallLoc, Param, ArgExpr: Arg);
6099
6100	AllArgs.push_back(Elt: Arg);
6101	}
6102
6103	// If this is a variadic call, handle args passed through "...".
6104	if (CallType != VariadicCallType::DoesNotApply) {
6105	// Assume that extern "C" functions with variadic arguments that
6106	// return __unknown_anytype aren't *really* variadic.
6107	if (Proto->getReturnType() == Context.UnknownAnyTy && FDecl &&
6108	FDecl->isExternC()) {
6109	for (Expr *A : Args.slice(N: ArgIx)) {
6110	QualType paramType; // ignored
6111	ExprResult arg = checkUnknownAnyArg(callLoc: CallLoc, result: A, paramType);
6112	Invalid |= arg.isInvalid();
6113	AllArgs.push_back(Elt: arg.get());
6114	}
6115
6116	// Otherwise do argument promotion, (C99 6.5.2.2p7).
6117	} else {
6118	for (Expr *A : Args.slice(N: ArgIx)) {
6119	ExprResult Arg = DefaultVariadicArgumentPromotion(E: A, CT: CallType, FDecl);
6120	Invalid |= Arg.isInvalid();
6121	AllArgs.push_back(Elt: Arg.get());
6122	}
6123	}
6124
6125	// Check for array bounds violations.
6126	for (Expr *A : Args.slice(N: ArgIx))
6127	CheckArrayAccess(E: A);
6128	}
6129	return Invalid;
6130	}
6131
6132	static void DiagnoseCalleeStaticArrayParam(Sema &S, ParmVarDecl *PVD) {
6133	TypeLoc TL = PVD->getTypeSourceInfo()->getTypeLoc();
6134	if (DecayedTypeLoc DTL = TL.getAs<DecayedTypeLoc>())
6135	TL = DTL.getOriginalLoc();
6136	if (ArrayTypeLoc ATL = TL.getAs<ArrayTypeLoc>())
6137	S.Diag(Loc: PVD->getLocation(), DiagID: diag::note_callee_static_array)
6138	<< ATL.getLocalSourceRange();
6139	}
6140
6141	void
6142	Sema::CheckStaticArrayArgument(SourceLocation CallLoc,
6143	ParmVarDecl *Param,
6144	const Expr *ArgExpr) {
6145	// Static array parameters are not supported in C++.
6146	if (!Param || getLangOpts().CPlusPlus)
6147	return;
6148
6149	QualType OrigTy = Param->getOriginalType();
6150
6151	const ArrayType *AT = Context.getAsArrayType(T: OrigTy);
6152	if (!AT || AT->getSizeModifier() != ArraySizeModifier::Static)
6153	return;
6154
6155	if (ArgExpr->isNullPointerConstant(Ctx&: Context,
6156	NPC: Expr::NPC_NeverValueDependent)) {
6157	Diag(Loc: CallLoc, DiagID: diag::warn_null_arg) << ArgExpr->getSourceRange();
6158	DiagnoseCalleeStaticArrayParam(S&: *this, PVD: Param);
6159	return;
6160	}
6161
6162	const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(Val: AT);
6163	if (!CAT)
6164	return;
6165
6166	const ConstantArrayType *ArgCAT =
6167	Context.getAsConstantArrayType(T: ArgExpr->IgnoreParenCasts()->getType());
6168	if (!ArgCAT)
6169	return;
6170
6171	if (getASTContext().hasSameUnqualifiedType(T1: CAT->getElementType(),
6172	T2: ArgCAT->getElementType())) {
6173	if (ArgCAT->getSize().ult(RHS: CAT->getSize())) {
6174	Diag(Loc: CallLoc, DiagID: diag::warn_static_array_too_small)
6175	<< ArgExpr->getSourceRange() << (unsigned)ArgCAT->getZExtSize()
6176	<< (unsigned)CAT->getZExtSize() << 0;
6177	DiagnoseCalleeStaticArrayParam(S&: *this, PVD: Param);
6178	}
6179	return;
6180	}
6181
6182	std::optional<CharUnits> ArgSize =
6183	getASTContext().getTypeSizeInCharsIfKnown(Ty: ArgCAT);
6184	std::optional<CharUnits> ParmSize =
6185	getASTContext().getTypeSizeInCharsIfKnown(Ty: CAT);
6186	if (ArgSize && ParmSize && *ArgSize < *ParmSize) {
6187	Diag(Loc: CallLoc, DiagID: diag::warn_static_array_too_small)
6188	<< ArgExpr->getSourceRange() << (unsigned)ArgSize->getQuantity()
6189	<< (unsigned)ParmSize->getQuantity() << 1;
6190	DiagnoseCalleeStaticArrayParam(S&: *this, PVD: Param);
6191	}
6192	}
6193
6194	/// Given a function expression of unknown-any type, try to rebuild it
6195	/// to have a function type.
6196	static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn);
6197
6198	/// Is the given type a placeholder that we need to lower out
6199	/// immediately during argument processing?
6200	static bool isPlaceholderToRemoveAsArg(QualType type) {
6201	// Placeholders are never sugared.
6202	const BuiltinType *placeholder = dyn_cast<BuiltinType>(Val&: type);
6203	if (!placeholder) return false;
6204
6205	switch (placeholder->getKind()) {
6206	// Ignore all the non-placeholder types.
6207	#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
6208	case BuiltinType::Id:
6209	#include "clang/Basic/OpenCLImageTypes.def"
6210	#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
6211	case BuiltinType::Id:
6212	#include "clang/Basic/OpenCLExtensionTypes.def"
6213	// In practice we'll never use this, since all SVE types are sugared
6214	// via TypedefTypes rather than exposed directly as BuiltinTypes.
6215	#define SVE_TYPE(Name, Id, SingletonId) \
6216	case BuiltinType::Id:
6217	#include "clang/Basic/AArch64ACLETypes.def"
6218	#define PPC_VECTOR_TYPE(Name, Id, Size) \
6219	case BuiltinType::Id:
6220	#include "clang/Basic/PPCTypes.def"
6221	#define RVV_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
6222	#include "clang/Basic/RISCVVTypes.def"
6223	#define WASM_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
6224	#include "clang/Basic/WebAssemblyReferenceTypes.def"
6225	#define AMDGPU_TYPE(Name, Id, SingletonId, Width, Align) case BuiltinType::Id:
6226	#include "clang/Basic/AMDGPUTypes.def"
6227	#define HLSL_INTANGIBLE_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
6228	#include "clang/Basic/HLSLIntangibleTypes.def"
6229	#define PLACEHOLDER_TYPE(ID, SINGLETON_ID)
6230	#define BUILTIN_TYPE(ID, SINGLETON_ID) case BuiltinType::ID:
6231	#include "clang/AST/BuiltinTypes.def"
6232	return false;
6233
6234	case BuiltinType::UnresolvedTemplate:
6235	// We cannot lower out overload sets; they might validly be resolved
6236	// by the call machinery.
6237	case BuiltinType::Overload:
6238	return false;
6239
6240	// Unbridged casts in ARC can be handled in some call positions and
6241	// should be left in place.
6242	case BuiltinType::ARCUnbridgedCast:
6243	return false;
6244
6245	// Pseudo-objects should be converted as soon as possible.
6246	case BuiltinType::PseudoObject:
6247	return true;
6248
6249	// The debugger mode could theoretically but currently does not try
6250	// to resolve unknown-typed arguments based on known parameter types.
6251	case BuiltinType::UnknownAny:
6252	return true;
6253
6254	// These are always invalid as call arguments and should be reported.
6255	case BuiltinType::BoundMember:
6256	case BuiltinType::BuiltinFn:
6257	case BuiltinType::IncompleteMatrixIdx:
6258	case BuiltinType::ArraySection:
6259	case BuiltinType::OMPArrayShaping:
6260	case BuiltinType::OMPIterator:
6261	return true;
6262
6263	}
6264	llvm_unreachable("bad builtin type kind");
6265	}
6266
6267	bool Sema::CheckArgsForPlaceholders(MultiExprArg args) {
6268	// Apply this processing to all the arguments at once instead of
6269	// dying at the first failure.
6270	bool hasInvalid = false;
6271	for (size_t i = 0, e = args.size(); i != e; i++) {
6272	if (isPlaceholderToRemoveAsArg(type: args[i]->getType())) {
6273	ExprResult result = CheckPlaceholderExpr(E: args[i]);
6274	if (result.isInvalid()) hasInvalid = true;
6275	else args[i] = result.get();
6276	}
6277	}
6278	return hasInvalid;
6279	}
6280
6281	/// If a builtin function has a pointer argument with no explicit address
6282	/// space, then it should be able to accept a pointer to any address
6283	/// space as input. In order to do this, we need to replace the
6284	/// standard builtin declaration with one that uses the same address space
6285	/// as the call.
6286	///
6287	/// \returns nullptr If this builtin is not a candidate for a rewrite i.e.
6288	/// it does not contain any pointer arguments without
6289	/// an address space qualifer. Otherwise the rewritten
6290	/// FunctionDecl is returned.
6291	/// TODO: Handle pointer return types.
6292	static FunctionDecl *rewriteBuiltinFunctionDecl(Sema *Sema, ASTContext &Context,
6293	FunctionDecl *FDecl,
6294	MultiExprArg ArgExprs) {
6295
6296	QualType DeclType = FDecl->getType();
6297	const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(Val&: DeclType);
6298
6299	if (!Context.BuiltinInfo.hasPtrArgsOrResult(ID: FDecl->getBuiltinID()) || !FT ||
6300	ArgExprs.size() < FT->getNumParams())
6301	return nullptr;
6302
6303	bool NeedsNewDecl = false;
6304	unsigned i = 0;
6305	SmallVector<QualType, 8> OverloadParams;
6306
6307	for (QualType ParamType : FT->param_types()) {
6308
6309	// Convert array arguments to pointer to simplify type lookup.
6310	ExprResult ArgRes =
6311	Sema->DefaultFunctionArrayLvalueConversion(E: ArgExprs[i++]);
6312	if (ArgRes.isInvalid())
6313	return nullptr;
6314	Expr *Arg = ArgRes.get();
6315	QualType ArgType = Arg->getType();
6316	if (!ParamType->isPointerType() ||
6317	ParamType->getPointeeType().hasAddressSpace() ||
6318	!ArgType->isPointerType() ||
6319	!ArgType->getPointeeType().hasAddressSpace() ||
6320	isPtrSizeAddressSpace(AS: ArgType->getPointeeType().getAddressSpace())) {
6321	OverloadParams.push_back(Elt: ParamType);
6322	continue;
6323	}
6324
6325	QualType PointeeType = ParamType->getPointeeType();
6326	NeedsNewDecl = true;
6327	LangAS AS = ArgType->getPointeeType().getAddressSpace();
6328
6329	PointeeType = Context.getAddrSpaceQualType(T: PointeeType, AddressSpace: AS);
6330	OverloadParams.push_back(Elt: Context.getPointerType(T: PointeeType));
6331	}
6332
6333	if (!NeedsNewDecl)
6334	return nullptr;
6335
6336	FunctionProtoType::ExtProtoInfo EPI;
6337	EPI.Variadic = FT->isVariadic();
6338	QualType OverloadTy = Context.getFunctionType(ResultTy: FT->getReturnType(),
6339	Args: OverloadParams, EPI);
6340	DeclContext *Parent = FDecl->getParent();
6341	FunctionDecl *OverloadDecl = FunctionDecl::Create(
6342	C&: Context, DC: Parent, StartLoc: FDecl->getLocation(), NLoc: FDecl->getLocation(),
6343	N: FDecl->getIdentifier(), T: OverloadTy,
6344	/*TInfo=*/nullptr, SC: SC_Extern, UsesFPIntrin: Sema->getCurFPFeatures().isFPConstrained(),
6345	isInlineSpecified: false,
6346	/*hasPrototype=*/hasWrittenPrototype: true);
6347	SmallVector<ParmVarDecl*, 16> Params;
6348	FT = cast<FunctionProtoType>(Val&: OverloadTy);
6349	for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
6350	QualType ParamType = FT->getParamType(i);
6351	ParmVarDecl *Parm =
6352	ParmVarDecl::Create(C&: Context, DC: OverloadDecl, StartLoc: SourceLocation(),
6353	IdLoc: SourceLocation(), Id: nullptr, T: ParamType,
6354	/*TInfo=*/nullptr, S: SC_None, DefArg: nullptr);
6355	Parm->setScopeInfo(scopeDepth: 0, parameterIndex: i);
6356	Params.push_back(Elt: Parm);
6357	}
6358	OverloadDecl->setParams(Params);
6359	// We cannot merge host/device attributes of redeclarations. They have to
6360	// be consistent when created.
6361	if (Sema->LangOpts.CUDA) {
6362	if (FDecl->hasAttr<CUDAHostAttr>())
6363	OverloadDecl->addAttr(A: CUDAHostAttr::CreateImplicit(Ctx&: Context));
6364	if (FDecl->hasAttr<CUDADeviceAttr>())
6365	OverloadDecl->addAttr(A: CUDADeviceAttr::CreateImplicit(Ctx&: Context));
6366	}
6367	Sema->mergeDeclAttributes(New: OverloadDecl, Old: FDecl);
6368	return OverloadDecl;
6369	}
6370
6371	static void checkDirectCallValidity(Sema &S, const Expr *Fn,
6372	FunctionDecl *Callee,
6373	MultiExprArg ArgExprs) {
6374	// `Callee` (when called with ArgExprs) may be ill-formed. enable_if (and
6375	// similar attributes) really don't like it when functions are called with an
6376	// invalid number of args.
6377	if (S.TooManyArguments(NumParams: Callee->getNumParams(), NumArgs: ArgExprs.size(),
6378	/*PartialOverloading=*/false) &&
6379	!Callee->isVariadic())
6380	return;
6381	if (Callee->getMinRequiredArguments() > ArgExprs.size())
6382	return;
6383
6384	if (const EnableIfAttr *Attr =
6385	S.CheckEnableIf(Function: Callee, CallLoc: Fn->getBeginLoc(), Args: ArgExprs, MissingImplicitThis: true)) {
6386	S.Diag(Loc: Fn->getBeginLoc(),
6387	DiagID: isa<CXXMethodDecl>(Val: Callee)
6388	? diag::err_ovl_no_viable_member_function_in_call
6389	: diag::err_ovl_no_viable_function_in_call)
6390	<< Callee << Callee->getSourceRange();
6391	S.Diag(Loc: Callee->getLocation(),
6392	DiagID: diag::note_ovl_candidate_disabled_by_function_cond_attr)
6393	<< Attr->getCond()->getSourceRange() << Attr->getMessage();
6394	return;
6395	}
6396	}
6397
6398	static bool enclosingClassIsRelatedToClassInWhichMembersWereFound(
6399	const UnresolvedMemberExpr *const UME, Sema &S) {
6400
6401	const auto GetFunctionLevelDCIfCXXClass =
6402	[](Sema &S) -> const CXXRecordDecl * {
6403	const DeclContext *const DC = S.getFunctionLevelDeclContext();
6404	if (!DC || !DC->getParent())
6405	return nullptr;
6406
6407	// If the call to some member function was made from within a member
6408	// function body 'M' return return 'M's parent.
6409	if (const auto *MD = dyn_cast<CXXMethodDecl>(Val: DC))
6410	return MD->getParent()->getCanonicalDecl();
6411	// else the call was made from within a default member initializer of a
6412	// class, so return the class.
6413	if (const auto *RD = dyn_cast<CXXRecordDecl>(Val: DC))
6414	return RD->getCanonicalDecl();
6415	return nullptr;
6416	};
6417	// If our DeclContext is neither a member function nor a class (in the
6418	// case of a lambda in a default member initializer), we can't have an
6419	// enclosing 'this'.
6420
6421	const CXXRecordDecl *const CurParentClass = GetFunctionLevelDCIfCXXClass(S);
6422	if (!CurParentClass)
6423	return false;
6424
6425	// The naming class for implicit member functions call is the class in which
6426	// name lookup starts.
6427	const CXXRecordDecl *const NamingClass =
6428	UME->getNamingClass()->getCanonicalDecl();
6429	assert(NamingClass && "Must have naming class even for implicit access");
6430
6431	// If the unresolved member functions were found in a 'naming class' that is
6432	// related (either the same or derived from) to the class that contains the
6433	// member function that itself contained the implicit member access.
6434
6435	return CurParentClass == NamingClass ||
6436	CurParentClass->isDerivedFrom(Base: NamingClass);
6437	}
6438
6439	static void
6440	tryImplicitlyCaptureThisIfImplicitMemberFunctionAccessWithDependentArgs(
6441	Sema &S, const UnresolvedMemberExpr *const UME, SourceLocation CallLoc) {
6442
6443	if (!UME)
6444	return;
6445
6446	LambdaScopeInfo *const CurLSI = S.getCurLambda();
6447	// Only try and implicitly capture 'this' within a C++ Lambda if it hasn't
6448	// already been captured, or if this is an implicit member function call (if
6449	// it isn't, an attempt to capture 'this' should already have been made).
6450	if (!CurLSI || CurLSI->ImpCaptureStyle == CurLSI->ImpCap_None ||
6451	!UME->isImplicitAccess() || CurLSI->isCXXThisCaptured())
6452	return;
6453
6454	// Check if the naming class in which the unresolved members were found is
6455	// related (same as or is a base of) to the enclosing class.
6456
6457	if (!enclosingClassIsRelatedToClassInWhichMembersWereFound(UME, S))
6458	return;
6459
6460
6461	DeclContext *EnclosingFunctionCtx = S.CurContext->getParent()->getParent();
6462	// If the enclosing function is not dependent, then this lambda is
6463	// capture ready, so if we can capture this, do so.
6464	if (!EnclosingFunctionCtx->isDependentContext()) {
6465	// If the current lambda and all enclosing lambdas can capture 'this' -
6466	// then go ahead and capture 'this' (since our unresolved overload set
6467	// contains at least one non-static member function).
6468	if (!S.CheckCXXThisCapture(Loc: CallLoc, /*Explcit*/ Explicit: false, /*Diagnose*/ BuildAndDiagnose: false))
6469	S.CheckCXXThisCapture(Loc: CallLoc);
6470	} else if (S.CurContext->isDependentContext()) {
6471	// ... since this is an implicit member reference, that might potentially
6472	// involve a 'this' capture, mark 'this' for potential capture in
6473	// enclosing lambdas.
6474	if (CurLSI->ImpCaptureStyle != CurLSI->ImpCap_None)
6475	CurLSI->addPotentialThisCapture(Loc: CallLoc);
6476	}
6477	}
6478
6479	// Once a call is fully resolved, warn for unqualified calls to specific
6480	// C++ standard functions, like move and forward.
6481	static void DiagnosedUnqualifiedCallsToStdFunctions(Sema &S,
6482	const CallExpr *Call) {
6483	// We are only checking unary move and forward so exit early here.
6484	if (Call->getNumArgs() != 1)
6485	return;
6486
6487	const Expr *E = Call->getCallee()->IgnoreParenImpCasts();
6488	if (!E || isa<UnresolvedLookupExpr>(Val: E))
6489	return;
6490	const DeclRefExpr *DRE = dyn_cast_if_present<DeclRefExpr>(Val: E);
6491	if (!DRE || !DRE->getLocation().isValid())
6492	return;
6493
6494	if (DRE->getQualifier())
6495	return;
6496
6497	const FunctionDecl *FD = Call->getDirectCallee();
6498	if (!FD)
6499	return;
6500
6501	// Only warn for some functions deemed more frequent or problematic.
6502	unsigned BuiltinID = FD->getBuiltinID();
6503	if (BuiltinID != Builtin::BImove && BuiltinID != Builtin::BIforward)
6504	return;
6505
6506	S.Diag(Loc: DRE->getLocation(), DiagID: diag::warn_unqualified_call_to_std_cast_function)
6507	<< FD->getQualifiedNameAsString()
6508	<< FixItHint::CreateInsertion(InsertionLoc: DRE->getLocation(), Code: "std::");
6509	}
6510
6511	ExprResult Sema::ActOnCallExpr(Scope *Scope, Expr *Fn, SourceLocation LParenLoc,
6512	MultiExprArg ArgExprs, SourceLocation RParenLoc,
6513	Expr *ExecConfig) {
6514	ExprResult Call =
6515	BuildCallExpr(S: Scope, Fn, LParenLoc, ArgExprs, RParenLoc, ExecConfig,
6516	/*IsExecConfig=*/false, /*AllowRecovery=*/true);
6517	if (Call.isInvalid())
6518	return Call;
6519
6520	// Diagnose uses of the C++20 "ADL-only template-id call" feature in earlier
6521	// language modes.
6522	if (const auto *ULE = dyn_cast<UnresolvedLookupExpr>(Val: Fn);
6523	ULE && ULE->hasExplicitTemplateArgs() &&
6524	ULE->decls_begin() == ULE->decls_end()) {
6525	DiagCompat(Loc: Fn->getExprLoc(), CompatDiagId: diag_compat::adl_only_template_id)
6526	<< ULE->getName();
6527	}
6528
6529	if (LangOpts.OpenMP)
6530	Call = OpenMP().ActOnOpenMPCall(Call, Scope, LParenLoc, ArgExprs, RParenLoc,
6531	ExecConfig);
6532	if (LangOpts.CPlusPlus) {
6533	if (const auto *CE = dyn_cast<CallExpr>(Val: Call.get()))
6534	DiagnosedUnqualifiedCallsToStdFunctions(S&: *this, Call: CE);
6535
6536	// If we previously found that the id-expression of this call refers to a
6537	// consteval function but the call is dependent, we should not treat is an
6538	// an invalid immediate call.
6539	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: Fn->IgnoreParens());
6540	DRE && Call.get()->isValueDependent()) {
6541	currentEvaluationContext().ReferenceToConsteval.erase(Ptr: DRE);
6542	}
6543	}
6544	return Call;
6545	}
6546
6547	// Any type that could be used to form a callable expression
6548	static bool MayBeFunctionType(const ASTContext &Context, const Expr *E) {
6549	QualType T = E->getType();
6550	if (T->isDependentType())
6551	return true;
6552
6553	if (T == Context.BoundMemberTy || T == Context.UnknownAnyTy ||
6554	T == Context.BuiltinFnTy || T == Context.OverloadTy ||
6555	T->isFunctionType() || T->isFunctionReferenceType() ||
6556	T->isMemberFunctionPointerType() || T->isFunctionPointerType() ||
6557	T->isBlockPointerType() || T->isRecordType())
6558	return true;
6559
6560	return isa<CallExpr, DeclRefExpr, MemberExpr, CXXPseudoDestructorExpr,
6561	OverloadExpr, UnresolvedMemberExpr, UnaryOperator>(Val: E);
6562	}
6563
6564	ExprResult Sema::BuildCallExpr(Scope *Scope, Expr *Fn, SourceLocation LParenLoc,
6565	MultiExprArg ArgExprs, SourceLocation RParenLoc,
6566	Expr *ExecConfig, bool IsExecConfig,
6567	bool AllowRecovery) {
6568	// Since this might be a postfix expression, get rid of ParenListExprs.
6569	ExprResult Result = MaybeConvertParenListExprToParenExpr(S: Scope, ME: Fn);
6570	if (Result.isInvalid()) return ExprError();
6571	Fn = Result.get();
6572
6573	if (CheckArgsForPlaceholders(args: ArgExprs))
6574	return ExprError();
6575
6576	// The result of __builtin_counted_by_ref cannot be used as a function
6577	// argument. It allows leaking and modification of bounds safety information.
6578	for (const Expr *Arg : ArgExprs)
6579	if (CheckInvalidBuiltinCountedByRef(E: Arg,
6580	K: BuiltinCountedByRefKind::FunctionArg))
6581	return ExprError();
6582
6583	if (getLangOpts().CPlusPlus) {
6584	// If this is a pseudo-destructor expression, build the call immediately.
6585	if (isa<CXXPseudoDestructorExpr>(Val: Fn)) {
6586	if (!ArgExprs.empty()) {
6587	// Pseudo-destructor calls should not have any arguments.
6588	Diag(Loc: Fn->getBeginLoc(), DiagID: diag::err_pseudo_dtor_call_with_args)
6589	<< FixItHint::CreateRemoval(
6590	RemoveRange: SourceRange(ArgExprs.front()->getBeginLoc(),
6591	ArgExprs.back()->getEndLoc()));
6592	}
6593
6594	return CallExpr::Create(Ctx: Context, Fn, /*Args=*/{}, Ty: Context.VoidTy,
6595	VK: VK_PRValue, RParenLoc, FPFeatures: CurFPFeatureOverrides());
6596	}
6597	if (Fn->getType() == Context.PseudoObjectTy) {
6598	ExprResult result = CheckPlaceholderExpr(E: Fn);
6599	if (result.isInvalid()) return ExprError();
6600	Fn = result.get();
6601	}
6602
6603	// Determine whether this is a dependent call inside a C++ template,
6604	// in which case we won't do any semantic analysis now.
6605	if (Fn->isTypeDependent() || Expr::hasAnyTypeDependentArguments(Exprs: ArgExprs)) {
6606	if (ExecConfig) {
6607	return CUDAKernelCallExpr::Create(Ctx: Context, Fn,
6608	Config: cast<CallExpr>(Val: ExecConfig), Args: ArgExprs,
6609	Ty: Context.DependentTy, VK: VK_PRValue,
6610	RP: RParenLoc, FPFeatures: CurFPFeatureOverrides());
6611	} else {
6612
6613	tryImplicitlyCaptureThisIfImplicitMemberFunctionAccessWithDependentArgs(
6614	S&: *this, UME: dyn_cast<UnresolvedMemberExpr>(Val: Fn->IgnoreParens()),
6615	CallLoc: Fn->getBeginLoc());
6616
6617	// If the type of the function itself is not dependent
6618	// check that it is a reasonable as a function, as type deduction
6619	// later assume the CallExpr has a sensible TYPE.
6620	if (!MayBeFunctionType(Context, E: Fn))
6621	return ExprError(
6622	Diag(Loc: LParenLoc, DiagID: diag::err_typecheck_call_not_function)
6623	<< Fn->getType() << Fn->getSourceRange());
6624
6625	return CallExpr::Create(Ctx: Context, Fn, Args: ArgExprs, Ty: Context.DependentTy,
6626	VK: VK_PRValue, RParenLoc, FPFeatures: CurFPFeatureOverrides());
6627	}
6628	}
6629
6630	// Determine whether this is a call to an object (C++ [over.call.object]).
6631	if (Fn->getType()->isRecordType())
6632	return BuildCallToObjectOfClassType(S: Scope, Object: Fn, LParenLoc, Args: ArgExprs,
6633	RParenLoc);
6634
6635	if (Fn->getType() == Context.UnknownAnyTy) {
6636	ExprResult result = rebuildUnknownAnyFunction(S&: *this, fn: Fn);
6637	if (result.isInvalid()) return ExprError();
6638	Fn = result.get();
6639	}
6640
6641	if (Fn->getType() == Context.BoundMemberTy) {
6642	return BuildCallToMemberFunction(S: Scope, MemExpr: Fn, LParenLoc, Args: ArgExprs,
6643	RParenLoc, ExecConfig, IsExecConfig,
6644	AllowRecovery);
6645	}
6646	}
6647
6648	// Check for overloaded calls. This can happen even in C due to extensions.
6649	if (Fn->getType() == Context.OverloadTy) {
6650	OverloadExpr::FindResult find = OverloadExpr::find(E: Fn);
6651
6652	// We aren't supposed to apply this logic if there's an '&' involved.
6653	if (!find.HasFormOfMemberPointer || find.IsAddressOfOperandWithParen) {
6654	if (Expr::hasAnyTypeDependentArguments(Exprs: ArgExprs))
6655	return CallExpr::Create(Ctx: Context, Fn, Args: ArgExprs, Ty: Context.DependentTy,
6656	VK: VK_PRValue, RParenLoc, FPFeatures: CurFPFeatureOverrides());
6657	OverloadExpr *ovl = find.Expression;
6658	if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Val: ovl))
6659	return BuildOverloadedCallExpr(
6660	S: Scope, Fn, ULE, LParenLoc, Args: ArgExprs, RParenLoc, ExecConfig,
6661	/*AllowTypoCorrection=*/true, CalleesAddressIsTaken: find.IsAddressOfOperand);
6662	return BuildCallToMemberFunction(S: Scope, MemExpr: Fn, LParenLoc, Args: ArgExprs,
6663	RParenLoc, ExecConfig, IsExecConfig,
6664	AllowRecovery);
6665	}
6666	}
6667
6668	// If we're directly calling a function, get the appropriate declaration.
6669	if (Fn->getType() == Context.UnknownAnyTy) {
6670	ExprResult result = rebuildUnknownAnyFunction(S&: *this, fn: Fn);
6671	if (result.isInvalid()) return ExprError();
6672	Fn = result.get();
6673	}
6674
6675	Expr *NakedFn = Fn->IgnoreParens();
6676
6677	bool CallingNDeclIndirectly = false;
6678	NamedDecl *NDecl = nullptr;
6679	if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Val: NakedFn)) {
6680	if (UnOp->getOpcode() == UO_AddrOf) {
6681	CallingNDeclIndirectly = true;
6682	NakedFn = UnOp->getSubExpr()->IgnoreParens();
6683	}
6684	}
6685
6686	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: NakedFn)) {
6687	NDecl = DRE->getDecl();
6688
6689	FunctionDecl *FDecl = dyn_cast<FunctionDecl>(Val: NDecl);
6690	if (FDecl && FDecl->getBuiltinID()) {
6691	// Rewrite the function decl for this builtin by replacing parameters
6692	// with no explicit address space with the address space of the arguments
6693	// in ArgExprs.
6694	if ((FDecl =
6695	rewriteBuiltinFunctionDecl(Sema: this, Context, FDecl, ArgExprs))) {
6696	NDecl = FDecl;
6697	Fn = DeclRefExpr::Create(
6698	Context, QualifierLoc: FDecl->getQualifierLoc(), TemplateKWLoc: SourceLocation(), D: FDecl, RefersToEnclosingVariableOrCapture: false,
6699	NameLoc: SourceLocation(), T: FDecl->getType(), VK: Fn->getValueKind(), FoundD: FDecl,
6700	TemplateArgs: nullptr, NOUR: DRE->isNonOdrUse());
6701	}
6702	}
6703	} else if (auto *ME = dyn_cast<MemberExpr>(Val: NakedFn))
6704	NDecl = ME->getMemberDecl();
6705
6706	if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(Val: NDecl)) {
6707	if (CallingNDeclIndirectly && !checkAddressOfFunctionIsAvailable(
6708	Function: FD, /*Complain=*/true, Loc: Fn->getBeginLoc()))
6709	return ExprError();
6710
6711	checkDirectCallValidity(S&: *this, Fn, Callee: FD, ArgExprs);
6712
6713	// If this expression is a call to a builtin function in HIP device
6714	// compilation, allow a pointer-type argument to default address space to be
6715	// passed as a pointer-type parameter to a non-default address space.
6716	// If Arg is declared in the default address space and Param is declared
6717	// in a non-default address space, perform an implicit address space cast to
6718	// the parameter type.
6719	if (getLangOpts().HIP && getLangOpts().CUDAIsDevice && FD &&
6720	FD->getBuiltinID()) {
6721	for (unsigned Idx = 0; Idx < ArgExprs.size() && Idx < FD->param_size();
6722	++Idx) {
6723	ParmVarDecl *Param = FD->getParamDecl(i: Idx);
6724	if (!ArgExprs[Idx] || !Param || !Param->getType()->isPointerType() ||
6725	!ArgExprs[Idx]->getType()->isPointerType())
6726	continue;
6727
6728	auto ParamAS = Param->getType()->getPointeeType().getAddressSpace();
6729	auto ArgTy = ArgExprs[Idx]->getType();
6730	auto ArgPtTy = ArgTy->getPointeeType();
6731	auto ArgAS = ArgPtTy.getAddressSpace();
6732
6733	// Add address space cast if target address spaces are different
6734	bool NeedImplicitASC =
6735	ParamAS != LangAS::Default && // Pointer params in generic AS don't need special handling.
6736	( ArgAS == LangAS::Default || // We do allow implicit conversion from generic AS
6737	// or from specific AS which has target AS matching that of Param.
6738	getASTContext().getTargetAddressSpace(AS: ArgAS) == getASTContext().getTargetAddressSpace(AS: ParamAS));
6739	if (!NeedImplicitASC)
6740	continue;
6741
6742	// First, ensure that the Arg is an RValue.
6743	if (ArgExprs[Idx]->isGLValue()) {
6744	ArgExprs[Idx] = ImplicitCastExpr::Create(
6745	Context, T: ArgExprs[Idx]->getType(), Kind: CK_NoOp, Operand: ArgExprs[Idx],
6746	BasePath: nullptr, Cat: VK_PRValue, FPO: FPOptionsOverride());
6747	}
6748
6749	// Construct a new arg type with address space of Param
6750	Qualifiers ArgPtQuals = ArgPtTy.getQualifiers();
6751	ArgPtQuals.setAddressSpace(ParamAS);
6752	auto NewArgPtTy =
6753	Context.getQualifiedType(T: ArgPtTy.getUnqualifiedType(), Qs: ArgPtQuals);
6754	auto NewArgTy =
6755	Context.getQualifiedType(T: Context.getPointerType(T: NewArgPtTy),
6756	Qs: ArgTy.getQualifiers());
6757
6758	// Finally perform an implicit address space cast
6759	ArgExprs[Idx] = ImpCastExprToType(E: ArgExprs[Idx], Type: NewArgTy,
6760	CK: CK_AddressSpaceConversion)
6761	.get();
6762	}
6763	}
6764	}
6765
6766	if (Context.isDependenceAllowed() &&
6767	(Fn->isTypeDependent() || Expr::hasAnyTypeDependentArguments(Exprs: ArgExprs))) {
6768	assert(!getLangOpts().CPlusPlus);
6769	assert((Fn->containsErrors() ||
6770	llvm::any_of(ArgExprs,
6771	[](clang::Expr *E) { return E->containsErrors(); })) &&
6772	"should only occur in error-recovery path.");
6773	return CallExpr::Create(Ctx: Context, Fn, Args: ArgExprs, Ty: Context.DependentTy,
6774	VK: VK_PRValue, RParenLoc, FPFeatures: CurFPFeatureOverrides());
6775	}
6776	return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Arg: ArgExprs, RParenLoc,
6777	Config: ExecConfig, IsExecConfig);
6778	}
6779
6780	Expr *Sema::BuildBuiltinCallExpr(SourceLocation Loc, Builtin::ID Id,
6781	MultiExprArg CallArgs) {
6782	std::string Name = Context.BuiltinInfo.getName(ID: Id);
6783	LookupResult R(*this, &Context.Idents.get(Name), Loc,
6784	Sema::LookupOrdinaryName);
6785	LookupName(R, S: TUScope, /*AllowBuiltinCreation=*/true);
6786
6787	auto *BuiltInDecl = R.getAsSingle<FunctionDecl>();
6788	assert(BuiltInDecl && "failed to find builtin declaration");
6789
6790	ExprResult DeclRef =
6791	BuildDeclRefExpr(D: BuiltInDecl, Ty: BuiltInDecl->getType(), VK: VK_LValue, Loc);
6792	assert(DeclRef.isUsable() && "Builtin reference cannot fail");
6793
6794	ExprResult Call =
6795	BuildCallExpr(/*Scope=*/nullptr, Fn: DeclRef.get(), LParenLoc: Loc, ArgExprs: CallArgs, RParenLoc: Loc);
6796
6797	assert(!Call.isInvalid() && "Call to builtin cannot fail!");
6798	return Call.get();
6799	}
6800
6801	ExprResult Sema::ActOnAsTypeExpr(Expr *E, ParsedType ParsedDestTy,
6802	SourceLocation BuiltinLoc,
6803	SourceLocation RParenLoc) {
6804	QualType DstTy = GetTypeFromParser(Ty: ParsedDestTy);
6805	return BuildAsTypeExpr(E, DestTy: DstTy, BuiltinLoc, RParenLoc);
6806	}
6807
6808	ExprResult Sema::BuildAsTypeExpr(Expr *E, QualType DestTy,
6809	SourceLocation BuiltinLoc,
6810	SourceLocation RParenLoc) {
6811	ExprValueKind VK = VK_PRValue;
6812	ExprObjectKind OK = OK_Ordinary;
6813	QualType SrcTy = E->getType();
6814	if (!SrcTy->isDependentType() &&
6815	Context.getTypeSize(T: DestTy) != Context.getTypeSize(T: SrcTy))
6816	return ExprError(
6817	Diag(Loc: BuiltinLoc, DiagID: diag::err_invalid_astype_of_different_size)
6818	<< DestTy << SrcTy << E->getSourceRange());
6819	return new (Context) AsTypeExpr(E, DestTy, VK, OK, BuiltinLoc, RParenLoc);
6820	}
6821
6822	ExprResult Sema::ActOnConvertVectorExpr(Expr *E, ParsedType ParsedDestTy,
6823	SourceLocation BuiltinLoc,
6824	SourceLocation RParenLoc) {
6825	TypeSourceInfo *TInfo;
6826	GetTypeFromParser(Ty: ParsedDestTy, TInfo: &TInfo);
6827	return ConvertVectorExpr(E, TInfo, BuiltinLoc, RParenLoc);
6828	}
6829
6830	ExprResult Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl,
6831	SourceLocation LParenLoc,
6832	ArrayRef<Expr *> Args,
6833	SourceLocation RParenLoc, Expr *Config,
6834	bool IsExecConfig, ADLCallKind UsesADL) {
6835	FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(Val: NDecl);
6836	unsigned BuiltinID = (FDecl ? FDecl->getBuiltinID() : 0);
6837
6838	// Functions with 'interrupt' attribute cannot be called directly.
6839	if (FDecl) {
6840	if (FDecl->hasAttr<AnyX86InterruptAttr>()) {
6841	Diag(Loc: Fn->getExprLoc(), DiagID: diag::err_anyx86_interrupt_called);
6842	return ExprError();
6843	}
6844	if (FDecl->hasAttr<ARMInterruptAttr>()) {
6845	Diag(Loc: Fn->getExprLoc(), DiagID: diag::err_arm_interrupt_called);
6846	return ExprError();
6847	}
6848	}
6849
6850	// X86 interrupt handlers may only call routines with attribute
6851	// no_caller_saved_registers since there is no efficient way to
6852	// save and restore the non-GPR state.
6853	if (auto *Caller = getCurFunctionDecl()) {
6854	if (Caller->hasAttr<AnyX86InterruptAttr>() ||
6855	Caller->hasAttr<AnyX86NoCallerSavedRegistersAttr>()) {
6856	const TargetInfo &TI = Context.getTargetInfo();
6857	bool HasNonGPRRegisters =
6858	TI.hasFeature(Feature: "sse") || TI.hasFeature(Feature: "x87") || TI.hasFeature(Feature: "mmx");
6859	if (HasNonGPRRegisters &&
6860	(!FDecl || !FDecl->hasAttr<AnyX86NoCallerSavedRegistersAttr>())) {
6861	Diag(Loc: Fn->getExprLoc(), DiagID: diag::warn_anyx86_excessive_regsave)
6862	<< (Caller->hasAttr<AnyX86InterruptAttr>() ? 0 : 1);
6863	if (FDecl)
6864	Diag(Loc: FDecl->getLocation(), DiagID: diag::note_callee_decl) << FDecl;
6865	}
6866	}
6867	}
6868
6869	// Promote the function operand.
6870	// We special-case function promotion here because we only allow promoting
6871	// builtin functions to function pointers in the callee of a call.
6872	ExprResult Result;
6873	QualType ResultTy;
6874	if (BuiltinID &&
6875	Fn->getType()->isSpecificBuiltinType(K: BuiltinType::BuiltinFn)) {
6876	// Extract the return type from the (builtin) function pointer type.
6877	// FIXME Several builtins still have setType in
6878	// Sema::CheckBuiltinFunctionCall. One should review their definitions in
6879	// Builtins.td to ensure they are correct before removing setType calls.
6880	QualType FnPtrTy = Context.getPointerType(T: FDecl->getType());
6881	Result = ImpCastExprToType(E: Fn, Type: FnPtrTy, CK: CK_BuiltinFnToFnPtr).get();
6882	ResultTy = FDecl->getCallResultType();
6883	} else {
6884	Result = CallExprUnaryConversions(E: Fn);
6885	ResultTy = Context.BoolTy;
6886	}
6887	if (Result.isInvalid())
6888	return ExprError();
6889	Fn = Result.get();
6890
6891	// Check for a valid function type, but only if it is not a builtin which
6892	// requires custom type checking. These will be handled by
6893	// CheckBuiltinFunctionCall below just after creation of the call expression.
6894	const FunctionType *FuncT = nullptr;
6895	if (!BuiltinID || !Context.BuiltinInfo.hasCustomTypechecking(ID: BuiltinID)) {
6896	retry:
6897	if (const PointerType *PT = Fn->getType()->getAs<PointerType>()) {
6898	// C99 6.5.2.2p1 - "The expression that denotes the called function shall
6899	// have type pointer to function".
6900	FuncT = PT->getPointeeType()->getAs<FunctionType>();
6901	if (!FuncT)
6902	return ExprError(Diag(Loc: LParenLoc, DiagID: diag::err_typecheck_call_not_function)
6903	<< Fn->getType() << Fn->getSourceRange());
6904	} else if (const BlockPointerType *BPT =
6905	Fn->getType()->getAs<BlockPointerType>()) {
6906	FuncT = BPT->getPointeeType()->castAs<FunctionType>();
6907	} else {
6908	// Handle calls to expressions of unknown-any type.
6909	if (Fn->getType() == Context.UnknownAnyTy) {
6910	ExprResult rewrite = rebuildUnknownAnyFunction(S&: *this, fn: Fn);
6911	if (rewrite.isInvalid())
6912	return ExprError();
6913	Fn = rewrite.get();
6914	goto retry;
6915	}
6916
6917	return ExprError(Diag(Loc: LParenLoc, DiagID: diag::err_typecheck_call_not_function)
6918	<< Fn->getType() << Fn->getSourceRange());
6919	}
6920	}
6921
6922	// Get the number of parameters in the function prototype, if any.
6923	// We will allocate space for max(Args.size(), NumParams) arguments
6924	// in the call expression.
6925	const auto *Proto = dyn_cast_or_null<FunctionProtoType>(Val: FuncT);
6926	unsigned NumParams = Proto ? Proto->getNumParams() : 0;
6927
6928	CallExpr *TheCall;
6929	if (Config) {
6930	assert(UsesADL == ADLCallKind::NotADL &&
6931	"CUDAKernelCallExpr should not use ADL");
6932	TheCall = CUDAKernelCallExpr::Create(Ctx: Context, Fn, Config: cast<CallExpr>(Val: Config),
6933	Args, Ty: ResultTy, VK: VK_PRValue, RP: RParenLoc,
6934	FPFeatures: CurFPFeatureOverrides(), MinNumArgs: NumParams);
6935	} else {
6936	TheCall =
6937	CallExpr::Create(Ctx: Context, Fn, Args, Ty: ResultTy, VK: VK_PRValue, RParenLoc,
6938	FPFeatures: CurFPFeatureOverrides(), MinNumArgs: NumParams, UsesADL);
6939	}
6940
6941	// Bail out early if calling a builtin with custom type checking.
6942	if (BuiltinID && Context.BuiltinInfo.hasCustomTypechecking(ID: BuiltinID)) {
6943	ExprResult E = CheckBuiltinFunctionCall(FDecl, BuiltinID, TheCall);
6944	if (!E.isInvalid() && Context.BuiltinInfo.isImmediate(ID: BuiltinID))
6945	E = CheckForImmediateInvocation(E, Decl: FDecl);
6946	return E;
6947	}
6948
6949	if (getLangOpts().CUDA) {
6950	if (Config) {
6951	// CUDA: Kernel calls must be to global functions
6952	if (FDecl && !FDecl->hasAttr<CUDAGlobalAttr>())
6953	return ExprError(Diag(Loc: LParenLoc,DiagID: diag::err_kern_call_not_global_function)
6954	<< FDecl << Fn->getSourceRange());
6955
6956	// CUDA: Kernel function must have 'void' return type
6957	if (!FuncT->getReturnType()->isVoidType() &&
6958	!FuncT->getReturnType()->getAs<AutoType>() &&
6959	!FuncT->getReturnType()->isInstantiationDependentType())
6960	return ExprError(Diag(Loc: LParenLoc, DiagID: diag::err_kern_type_not_void_return)
6961	<< Fn->getType() << Fn->getSourceRange());
6962	} else {
6963	// CUDA: Calls to global functions must be configured
6964	if (FDecl && FDecl->hasAttr<CUDAGlobalAttr>())
6965	return ExprError(Diag(Loc: LParenLoc, DiagID: diag::err_global_call_not_config)
6966	<< FDecl << Fn->getSourceRange());
6967	}
6968	}
6969
6970	// Check for a valid return type
6971	if (CheckCallReturnType(ReturnType: FuncT->getReturnType(), Loc: Fn->getBeginLoc(), CE: TheCall,
6972	FD: FDecl))
6973	return ExprError();
6974
6975	// We know the result type of the call, set it.
6976	TheCall->setType(FuncT->getCallResultType(Context));
6977	TheCall->setValueKind(Expr::getValueKindForType(T: FuncT->getReturnType()));
6978
6979	// WebAssembly tables can't be used as arguments.
6980	if (Context.getTargetInfo().getTriple().isWasm()) {
6981	for (const Expr *Arg : Args) {
6982	if (Arg && Arg->getType()->isWebAssemblyTableType()) {
6983	return ExprError(Diag(Loc: Arg->getExprLoc(),
6984	DiagID: diag::err_wasm_table_as_function_parameter));
6985	}
6986	}
6987	}
6988
6989	if (Proto) {
6990	if (ConvertArgumentsForCall(Call: TheCall, Fn, FDecl, Proto, Args, RParenLoc,
6991	IsExecConfig))
6992	return ExprError();
6993	} else {
6994	assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!");
6995
6996	if (FDecl) {
6997	// Check if we have too few/too many template arguments, based
6998	// on our knowledge of the function definition.
6999	const FunctionDecl *Def = nullptr;
7000	if (FDecl->hasBody(Definition&: Def) && Args.size() != Def->param_size()) {
7001	Proto = Def->getType()->getAs<FunctionProtoType>();
7002	if (!Proto || !(Proto->isVariadic() && Args.size() >= Def->param_size()))
7003	Diag(Loc: RParenLoc, DiagID: diag::warn_call_wrong_number_of_arguments)
7004	<< (Args.size() > Def->param_size()) << FDecl << Fn->getSourceRange();
7005	}
7006
7007	// If the function we're calling isn't a function prototype, but we have
7008	// a function prototype from a prior declaratiom, use that prototype.
7009	if (!FDecl->hasPrototype())
7010	Proto = FDecl->getType()->getAs<FunctionProtoType>();
7011	}
7012
7013	// If we still haven't found a prototype to use but there are arguments to
7014	// the call, diagnose this as calling a function without a prototype.
7015	// However, if we found a function declaration, check to see if
7016	// -Wdeprecated-non-prototype was disabled where the function was declared.
7017	// If so, we will silence the diagnostic here on the assumption that this
7018	// interface is intentional and the user knows what they're doing. We will
7019	// also silence the diagnostic if there is a function declaration but it
7020	// was implicitly defined (the user already gets diagnostics about the
7021	// creation of the implicit function declaration, so the additional warning
7022	// is not helpful).
7023	if (!Proto && !Args.empty() &&
7024	(!FDecl || (!FDecl->isImplicit() &&
7025	!Diags.isIgnored(DiagID: diag::warn_strict_uses_without_prototype,
7026	Loc: FDecl->getLocation()))))
7027	Diag(Loc: LParenLoc, DiagID: diag::warn_strict_uses_without_prototype)
7028	<< (FDecl != nullptr) << FDecl;
7029
7030	// Promote the arguments (C99 6.5.2.2p6).
7031	for (unsigned i = 0, e = Args.size(); i != e; i++) {
7032	Expr *Arg = Args[i];
7033
7034	if (Proto && i < Proto->getNumParams()) {
7035	InitializedEntity Entity = InitializedEntity::InitializeParameter(
7036	Context, Type: Proto->getParamType(i), Consumed: Proto->isParamConsumed(I: i));
7037	ExprResult ArgE =
7038	PerformCopyInitialization(Entity, EqualLoc: SourceLocation(), Init: Arg);
7039	if (ArgE.isInvalid())
7040	return true;
7041
7042	Arg = ArgE.getAs<Expr>();
7043
7044	} else {
7045	ExprResult ArgE = DefaultArgumentPromotion(E: Arg);
7046
7047	if (ArgE.isInvalid())
7048	return true;
7049
7050	Arg = ArgE.getAs<Expr>();
7051	}
7052
7053	if (RequireCompleteType(Loc: Arg->getBeginLoc(), T: Arg->getType(),
7054	DiagID: diag::err_call_incomplete_argument, Args: Arg))
7055	return ExprError();
7056
7057	TheCall->setArg(Arg: i, ArgExpr: Arg);
7058	}
7059	TheCall->computeDependence();
7060	}
7061
7062	if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(Val: FDecl))
7063	if (Method->isImplicitObjectMemberFunction())
7064	return ExprError(Diag(Loc: LParenLoc, DiagID: diag::err_member_call_without_object)
7065	<< Fn->getSourceRange() << 0);
7066
7067	// Check for sentinels
7068	if (NDecl)
7069	DiagnoseSentinelCalls(D: NDecl, Loc: LParenLoc, Args);
7070
7071	// Warn for unions passing across security boundary (CMSE).
7072	if (FuncT != nullptr && FuncT->getCmseNSCallAttr()) {
7073	for (unsigned i = 0, e = Args.size(); i != e; i++) {
7074	if (const auto *RT =
7075	dyn_cast<RecordType>(Val: Args[i]->getType().getCanonicalType())) {
7076	if (RT->getDecl()->isOrContainsUnion())
7077	Diag(Loc: Args[i]->getBeginLoc(), DiagID: diag::warn_cmse_nonsecure_union)
7078	<< 0 << i;
7079	}
7080	}
7081	}
7082
7083	// Do special checking on direct calls to functions.
7084	if (FDecl) {
7085	if (CheckFunctionCall(FDecl, TheCall, Proto))
7086	return ExprError();
7087
7088	checkFortifiedBuiltinMemoryFunction(FD: FDecl, TheCall);
7089
7090	if (BuiltinID)
7091	return CheckBuiltinFunctionCall(FDecl, BuiltinID, TheCall);
7092	} else if (NDecl) {
7093	if (CheckPointerCall(NDecl, TheCall, Proto))
7094	return ExprError();
7095	} else {
7096	if (CheckOtherCall(TheCall, Proto))
7097	return ExprError();
7098	}
7099
7100	return CheckForImmediateInvocation(E: MaybeBindToTemporary(E: TheCall), Decl: FDecl);
7101	}
7102
7103	ExprResult
7104	Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty,
7105	SourceLocation RParenLoc, Expr *InitExpr) {
7106	assert(Ty && "ActOnCompoundLiteral(): missing type");
7107	assert(InitExpr && "ActOnCompoundLiteral(): missing expression");
7108
7109	TypeSourceInfo *TInfo;
7110	QualType literalType = GetTypeFromParser(Ty, TInfo: &TInfo);
7111	if (!TInfo)
7112	TInfo = Context.getTrivialTypeSourceInfo(T: literalType);
7113
7114	return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, LiteralExpr: InitExpr);
7115	}
7116
7117	ExprResult
7118	Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo,
7119	SourceLocation RParenLoc, Expr *LiteralExpr) {
7120	QualType literalType = TInfo->getType();
7121
7122	if (literalType->isArrayType()) {
7123	if (RequireCompleteSizedType(
7124	Loc: LParenLoc, T: Context.getBaseElementType(QT: literalType),
7125	DiagID: diag::err_array_incomplete_or_sizeless_type,
7126	Args: SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd())))
7127	return ExprError();
7128	if (literalType->isVariableArrayType()) {
7129	// C23 6.7.10p4: An entity of variable length array type shall not be
7130	// initialized except by an empty initializer.
7131	//
7132	// The C extension warnings are issued from ParseBraceInitializer() and
7133	// do not need to be issued here. However, we continue to issue an error
7134	// in the case there are initializers or we are compiling C++. We allow
7135	// use of VLAs in C++, but it's not clear we want to allow {} to zero
7136	// init a VLA in C++ in all cases (such as with non-trivial constructors).
7137	// FIXME: should we allow this construct in C++ when it makes sense to do
7138	// so?
7139	//
7140	// But: C99-C23 6.5.2.5 Compound literals constraint 1: The type name
7141	// shall specify an object type or an array of unknown size, but not a
7142	// variable length array type. This seems odd, as it allows 'int a[size] =
7143	// {}', but forbids 'int *a = (int[size]){}'. As this is what the standard
7144	// says, this is what's implemented here for C (except for the extension
7145	// that permits constant foldable size arrays)
7146
7147	auto diagID = LangOpts.CPlusPlus
7148	? diag::err_variable_object_no_init
7149	: diag::err_compound_literal_with_vla_type;
7150	if (!tryToFixVariablyModifiedVarType(TInfo, T&: literalType, Loc: LParenLoc,
7151	FailedFoldDiagID: diagID))
7152	return ExprError();
7153	}
7154	} else if (!literalType->isDependentType() &&
7155	RequireCompleteType(Loc: LParenLoc, T: literalType,
7156	DiagID: diag::err_typecheck_decl_incomplete_type,
7157	Args: SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd())))
7158	return ExprError();
7159
7160	InitializedEntity Entity
7161	= InitializedEntity::InitializeCompoundLiteralInit(TSI: TInfo);
7162	InitializationKind Kind
7163	= InitializationKind::CreateCStyleCast(StartLoc: LParenLoc,
7164	TypeRange: SourceRange(LParenLoc, RParenLoc),
7165	/*InitList=*/true);
7166	InitializationSequence InitSeq(*this, Entity, Kind, LiteralExpr);
7167	ExprResult Result = InitSeq.Perform(S&: *this, Entity, Kind, Args: LiteralExpr,
7168	ResultType: &literalType);
7169	if (Result.isInvalid())
7170	return ExprError();
7171	LiteralExpr = Result.get();
7172
7173	// We treat the compound literal as being at file scope if it's not in a
7174	// function or method body, or within the function's prototype scope. This
7175	// means the following compound literal is not at file scope:
7176	// void func(char *para[(int [1]){ 0 }[0]);
7177	const Scope *S = getCurScope();
7178	bool IsFileScope = !CurContext->isFunctionOrMethod() &&
7179	!S->isInCFunctionScope() &&
7180	(!S || !S->isFunctionPrototypeScope());
7181
7182	// In C, compound literals are l-values for some reason.
7183	// For GCC compatibility, in C++, file-scope array compound literals with
7184	// constant initializers are also l-values, and compound literals are
7185	// otherwise prvalues.
7186	//
7187	// (GCC also treats C++ list-initialized file-scope array prvalues with
7188	// constant initializers as l-values, but that's non-conforming, so we don't
7189	// follow it there.)
7190	//
7191	// FIXME: It would be better to handle the lvalue cases as materializing and
7192	// lifetime-extending a temporary object, but our materialized temporaries
7193	// representation only supports lifetime extension from a variable, not "out
7194	// of thin air".
7195	// FIXME: For C++, we might want to instead lifetime-extend only if a pointer
7196	// is bound to the result of applying array-to-pointer decay to the compound
7197	// literal.
7198	// FIXME: GCC supports compound literals of reference type, which should
7199	// obviously have a value kind derived from the kind of reference involved.
7200	ExprValueKind VK =
7201	(getLangOpts().CPlusPlus && !(IsFileScope && literalType->isArrayType()))
7202	? VK_PRValue
7203	: VK_LValue;
7204
7205	// C99 6.5.2.5
7206	// "If the compound literal occurs outside the body of a function, the
7207	// initializer list shall consist of constant expressions."
7208	if (IsFileScope)
7209	if (auto ILE = dyn_cast<InitListExpr>(Val: LiteralExpr))
7210	for (unsigned i = 0, j = ILE->getNumInits(); i != j; i++) {
7211	Expr *Init = ILE->getInit(Init: i);
7212	if (!Init->isTypeDependent() && !Init->isValueDependent() &&
7213	!Init->isConstantInitializer(Ctx&: Context, /*IsForRef=*/ForRef: false)) {
7214	Diag(Loc: Init->getExprLoc(), DiagID: diag::err_init_element_not_constant)
7215	<< Init->getSourceBitField();
7216	return ExprError();
7217	}
7218
7219	ILE->setInit(Init: i, expr: ConstantExpr::Create(Context, E: Init));
7220	}
7221
7222	auto *E = new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, VK,
7223	LiteralExpr, IsFileScope);
7224	if (IsFileScope) {
7225	if (!LiteralExpr->isTypeDependent() &&
7226	!LiteralExpr->isValueDependent() &&
7227	!literalType->isDependentType()) // C99 6.5.2.5p3
7228	if (CheckForConstantInitializer(Init: LiteralExpr))
7229	return ExprError();
7230	} else if (literalType.getAddressSpace() != LangAS::opencl_private &&
7231	literalType.getAddressSpace() != LangAS::Default) {
7232	// Embedded-C extensions to C99 6.5.2.5:
7233	// "If the compound literal occurs inside the body of a function, the
7234	// type name shall not be qualified by an address-space qualifier."
7235	Diag(Loc: LParenLoc, DiagID: diag::err_compound_literal_with_address_space)
7236	<< SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd());
7237	return ExprError();
7238	}
7239
7240	if (!IsFileScope && !getLangOpts().CPlusPlus) {
7241	// Compound literals that have automatic storage duration are destroyed at
7242	// the end of the scope in C; in C++, they're just temporaries.
7243
7244	// Emit diagnostics if it is or contains a C union type that is non-trivial
7245	// to destruct.
7246	if (E->getType().hasNonTrivialToPrimitiveDestructCUnion())
7247	checkNonTrivialCUnion(QT: E->getType(), Loc: E->getExprLoc(),
7248	UseContext: NonTrivialCUnionContext::CompoundLiteral,
7249	NonTrivialKind: NTCUK_Destruct);
7250
7251	// Diagnose jumps that enter or exit the lifetime of the compound literal.
7252	if (literalType.isDestructedType()) {
7253	Cleanup.setExprNeedsCleanups(true);
7254	ExprCleanupObjects.push_back(Elt: E);
7255	getCurFunction()->setHasBranchProtectedScope();
7256	}
7257	}
7258
7259	if (E->getType().hasNonTrivialToPrimitiveDefaultInitializeCUnion() ||
7260	E->getType().hasNonTrivialToPrimitiveCopyCUnion())
7261	checkNonTrivialCUnionInInitializer(Init: E->getInitializer(),
7262	Loc: E->getInitializer()->getExprLoc());
7263
7264	return MaybeBindToTemporary(E);
7265	}
7266
7267	ExprResult
7268	Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg InitArgList,
7269	SourceLocation RBraceLoc) {
7270	// Only produce each kind of designated initialization diagnostic once.
7271	SourceLocation FirstDesignator;
7272	bool DiagnosedArrayDesignator = false;
7273	bool DiagnosedNestedDesignator = false;
7274	bool DiagnosedMixedDesignator = false;
7275
7276	// Check that any designated initializers are syntactically valid in the
7277	// current language mode.
7278	for (unsigned I = 0, E = InitArgList.size(); I != E; ++I) {
7279	if (auto *DIE = dyn_cast<DesignatedInitExpr>(Val: InitArgList[I])) {
7280	if (FirstDesignator.isInvalid())
7281	FirstDesignator = DIE->getBeginLoc();
7282
7283	if (!getLangOpts().CPlusPlus)
7284	break;
7285
7286	if (!DiagnosedNestedDesignator && DIE->size() > 1) {
7287	DiagnosedNestedDesignator = true;
7288	Diag(Loc: DIE->getBeginLoc(), DiagID: diag::ext_designated_init_nested)
7289	<< DIE->getDesignatorsSourceRange();
7290	}
7291
7292	for (auto &Desig : DIE->designators()) {
7293	if (!Desig.isFieldDesignator() && !DiagnosedArrayDesignator) {
7294	DiagnosedArrayDesignator = true;
7295	Diag(Loc: Desig.getBeginLoc(), DiagID: diag::ext_designated_init_array)
7296	<< Desig.getSourceRange();
7297	}
7298	}
7299
7300	if (!DiagnosedMixedDesignator &&
7301	!isa<DesignatedInitExpr>(Val: InitArgList[0])) {
7302	DiagnosedMixedDesignator = true;
7303	Diag(Loc: DIE->getBeginLoc(), DiagID: diag::ext_designated_init_mixed)
7304	<< DIE->getSourceRange();
7305	Diag(Loc: InitArgList[0]->getBeginLoc(), DiagID: diag::note_designated_init_mixed)
7306	<< InitArgList[0]->getSourceRange();
7307	}
7308	} else if (getLangOpts().CPlusPlus && !DiagnosedMixedDesignator &&
7309	isa<DesignatedInitExpr>(Val: InitArgList[0])) {
7310	DiagnosedMixedDesignator = true;
7311	auto *DIE = cast<DesignatedInitExpr>(Val: InitArgList[0]);
7312	Diag(Loc: DIE->getBeginLoc(), DiagID: diag::ext_designated_init_mixed)
7313	<< DIE->getSourceRange();
7314	Diag(Loc: InitArgList[I]->getBeginLoc(), DiagID: diag::note_designated_init_mixed)
7315	<< InitArgList[I]->getSourceRange();
7316	}
7317	}
7318
7319	if (FirstDesignator.isValid()) {
7320	// Only diagnose designated initiaization as a C++20 extension if we didn't
7321	// already diagnose use of (non-C++20) C99 designator syntax.
7322	if (getLangOpts().CPlusPlus && !DiagnosedArrayDesignator &&
7323	!DiagnosedNestedDesignator && !DiagnosedMixedDesignator) {
7324	Diag(Loc: FirstDesignator, DiagID: getLangOpts().CPlusPlus20
7325	? diag::warn_cxx17_compat_designated_init
7326	: diag::ext_cxx_designated_init);
7327	} else if (!getLangOpts().CPlusPlus && !getLangOpts().C99) {
7328	Diag(Loc: FirstDesignator, DiagID: diag::ext_designated_init);
7329	}
7330	}
7331
7332	return BuildInitList(LBraceLoc, InitArgList, RBraceLoc);
7333	}
7334
7335	ExprResult
7336	Sema::BuildInitList(SourceLocation LBraceLoc, MultiExprArg InitArgList,
7337	SourceLocation RBraceLoc) {
7338	// Semantic analysis for initializers is done by ActOnDeclarator() and
7339	// CheckInitializer() - it requires knowledge of the object being initialized.
7340
7341	// Immediately handle non-overload placeholders. Overloads can be
7342	// resolved contextually, but everything else here can't.
7343	for (unsigned I = 0, E = InitArgList.size(); I != E; ++I) {
7344	if (InitArgList[I]->getType()->isNonOverloadPlaceholderType()) {
7345	ExprResult result = CheckPlaceholderExpr(E: InitArgList[I]);
7346
7347	// Ignore failures; dropping the entire initializer list because
7348	// of one failure would be terrible for indexing/etc.
7349	if (result.isInvalid()) continue;
7350
7351	InitArgList[I] = result.get();
7352	}
7353	}
7354
7355	InitListExpr *E =
7356	new (Context) InitListExpr(Context, LBraceLoc, InitArgList, RBraceLoc);
7357	E->setType(Context.VoidTy); // FIXME: just a place holder for now.
7358	return E;
7359	}
7360
7361	void Sema::maybeExtendBlockObject(ExprResult &E) {
7362	assert(E.get()->getType()->isBlockPointerType());
7363	assert(E.get()->isPRValue());
7364
7365	// Only do this in an r-value context.
7366	if (!getLangOpts().ObjCAutoRefCount) return;
7367
7368	E = ImplicitCastExpr::Create(
7369	Context, T: E.get()->getType(), Kind: CK_ARCExtendBlockObject, Operand: E.get(),
7370	/*base path*/ BasePath: nullptr, Cat: VK_PRValue, FPO: FPOptionsOverride());
7371	Cleanup.setExprNeedsCleanups(true);
7372	}
7373
7374	CastKind Sema::PrepareScalarCast(ExprResult &Src, QualType DestTy) {
7375	// Both Src and Dest are scalar types, i.e. arithmetic or pointer.
7376	// Also, callers should have filtered out the invalid cases with
7377	// pointers. Everything else should be possible.
7378
7379	QualType SrcTy = Src.get()->getType();
7380	if (Context.hasSameUnqualifiedType(T1: SrcTy, T2: DestTy))
7381	return CK_NoOp;
7382
7383	switch (Type::ScalarTypeKind SrcKind = SrcTy->getScalarTypeKind()) {
7384	case Type::STK_MemberPointer:
7385	llvm_unreachable("member pointer type in C");
7386
7387	case Type::STK_CPointer:
7388	case Type::STK_BlockPointer:
7389	case Type::STK_ObjCObjectPointer:
7390	switch (DestTy->getScalarTypeKind()) {
7391	case Type::STK_CPointer: {
7392	LangAS SrcAS = SrcTy->getPointeeType().getAddressSpace();
7393	LangAS DestAS = DestTy->getPointeeType().getAddressSpace();
7394	if (SrcAS != DestAS)
7395	return CK_AddressSpaceConversion;
7396	if (Context.hasCvrSimilarType(T1: SrcTy, T2: DestTy))
7397	return CK_NoOp;
7398	return CK_BitCast;
7399	}
7400	case Type::STK_BlockPointer:
7401	return (SrcKind == Type::STK_BlockPointer
7402	? CK_BitCast : CK_AnyPointerToBlockPointerCast);
7403	case Type::STK_ObjCObjectPointer:
7404	if (SrcKind == Type::STK_ObjCObjectPointer)
7405	return CK_BitCast;
7406	if (SrcKind == Type::STK_CPointer)
7407	return CK_CPointerToObjCPointerCast;
7408	maybeExtendBlockObject(E&: Src);
7409	return CK_BlockPointerToObjCPointerCast;
7410	case Type::STK_Bool:
7411	return CK_PointerToBoolean;
7412	case Type::STK_Integral:
7413	return CK_PointerToIntegral;
7414	case Type::STK_Floating:
7415	case Type::STK_FloatingComplex:
7416	case Type::STK_IntegralComplex:
7417	case Type::STK_MemberPointer:
7418	case Type::STK_FixedPoint:
7419	llvm_unreachable("illegal cast from pointer");
7420	}
7421	llvm_unreachable("Should have returned before this");
7422
7423	case Type::STK_FixedPoint:
7424	switch (DestTy->getScalarTypeKind()) {
7425	case Type::STK_FixedPoint:
7426	return CK_FixedPointCast;
7427	case Type::STK_Bool:
7428	return CK_FixedPointToBoolean;
7429	case Type::STK_Integral:
7430	return CK_FixedPointToIntegral;
7431	case Type::STK_Floating:
7432	return CK_FixedPointToFloating;
7433	case Type::STK_IntegralComplex:
7434	case Type::STK_FloatingComplex:
7435	Diag(Loc: Src.get()->getExprLoc(),
7436	DiagID: diag::err_unimplemented_conversion_with_fixed_point_type)
7437	<< DestTy;
7438	return CK_IntegralCast;
7439	case Type::STK_CPointer:
7440	case Type::STK_ObjCObjectPointer:
7441	case Type::STK_BlockPointer:
7442	case Type::STK_MemberPointer:
7443	llvm_unreachable("illegal cast to pointer type");
7444	}
7445	llvm_unreachable("Should have returned before this");
7446
7447	case Type::STK_Bool: // casting from bool is like casting from an integer
7448	case Type::STK_Integral:
7449	switch (DestTy->getScalarTypeKind()) {
7450	case Type::STK_CPointer:
7451	case Type::STK_ObjCObjectPointer:
7452	case Type::STK_BlockPointer:
7453	if (Src.get()->isNullPointerConstant(Ctx&: Context,
7454	NPC: Expr::NPC_ValueDependentIsNull))
7455	return CK_NullToPointer;
7456	return CK_IntegralToPointer;
7457	case Type::STK_Bool:
7458	return CK_IntegralToBoolean;
7459	case Type::STK_Integral:
7460	return CK_IntegralCast;
7461	case Type::STK_Floating:
7462	return CK_IntegralToFloating;
7463	case Type::STK_IntegralComplex:
7464	Src = ImpCastExprToType(E: Src.get(),
7465	Type: DestTy->castAs<ComplexType>()->getElementType(),
7466	CK: CK_IntegralCast);
7467	return CK_IntegralRealToComplex;
7468	case Type::STK_FloatingComplex:
7469	Src = ImpCastExprToType(E: Src.get(),
7470	Type: DestTy->castAs<ComplexType>()->getElementType(),
7471	CK: CK_IntegralToFloating);
7472	return CK_FloatingRealToComplex;
7473	case Type::STK_MemberPointer:
7474	llvm_unreachable("member pointer type in C");
7475	case Type::STK_FixedPoint:
7476	return CK_IntegralToFixedPoint;
7477	}
7478	llvm_unreachable("Should have returned before this");
7479
7480	case Type::STK_Floating:
7481	switch (DestTy->getScalarTypeKind()) {
7482	case Type::STK_Floating:
7483	return CK_FloatingCast;
7484	case Type::STK_Bool:
7485	return CK_FloatingToBoolean;
7486	case Type::STK_Integral:
7487	return CK_FloatingToIntegral;
7488	case Type::STK_FloatingComplex:
7489	Src = ImpCastExprToType(E: Src.get(),
7490	Type: DestTy->castAs<ComplexType>()->getElementType(),
7491	CK: CK_FloatingCast);
7492	return CK_FloatingRealToComplex;
7493	case Type::STK_IntegralComplex:
7494	Src = ImpCastExprToType(E: Src.get(),
7495	Type: DestTy->castAs<ComplexType>()->getElementType(),
7496	CK: CK_FloatingToIntegral);
7497	return CK_IntegralRealToComplex;
7498	case Type::STK_CPointer:
7499	case Type::STK_ObjCObjectPointer:
7500	case Type::STK_BlockPointer:
7501	llvm_unreachable("valid float->pointer cast?");
7502	case Type::STK_MemberPointer:
7503	llvm_unreachable("member pointer type in C");
7504	case Type::STK_FixedPoint:
7505	return CK_FloatingToFixedPoint;
7506	}
7507	llvm_unreachable("Should have returned before this");
7508
7509	case Type::STK_FloatingComplex:
7510	switch (DestTy->getScalarTypeKind()) {
7511	case Type::STK_FloatingComplex:
7512	return CK_FloatingComplexCast;
7513	case Type::STK_IntegralComplex:
7514	return CK_FloatingComplexToIntegralComplex;
7515	case Type::STK_Floating: {
7516	QualType ET = SrcTy->castAs<ComplexType>()->getElementType();
7517	if (Context.hasSameType(T1: ET, T2: DestTy))
7518	return CK_FloatingComplexToReal;
7519	Src = ImpCastExprToType(E: Src.get(), Type: ET, CK: CK_FloatingComplexToReal);
7520	return CK_FloatingCast;
7521	}
7522	case Type::STK_Bool:
7523	return CK_FloatingComplexToBoolean;
7524	case Type::STK_Integral:
7525	Src = ImpCastExprToType(E: Src.get(),
7526	Type: SrcTy->castAs<ComplexType>()->getElementType(),
7527	CK: CK_FloatingComplexToReal);
7528	return CK_FloatingToIntegral;
7529	case Type::STK_CPointer:
7530	case Type::STK_ObjCObjectPointer:
7531	case Type::STK_BlockPointer:
7532	llvm_unreachable("valid complex float->pointer cast?");
7533	case Type::STK_MemberPointer:
7534	llvm_unreachable("member pointer type in C");
7535	case Type::STK_FixedPoint:
7536	Diag(Loc: Src.get()->getExprLoc(),
7537	DiagID: diag::err_unimplemented_conversion_with_fixed_point_type)
7538	<< SrcTy;
7539	return CK_IntegralCast;
7540	}
7541	llvm_unreachable("Should have returned before this");
7542
7543	case Type::STK_IntegralComplex:
7544	switch (DestTy->getScalarTypeKind()) {
7545	case Type::STK_FloatingComplex:
7546	return CK_IntegralComplexToFloatingComplex;
7547	case Type::STK_IntegralComplex:
7548	return CK_IntegralComplexCast;
7549	case Type::STK_Integral: {
7550	QualType ET = SrcTy->castAs<ComplexType>()->getElementType();
7551	if (Context.hasSameType(T1: ET, T2: DestTy))
7552	return CK_IntegralComplexToReal;
7553	Src = ImpCastExprToType(E: Src.get(), Type: ET, CK: CK_IntegralComplexToReal);
7554	return CK_IntegralCast;
7555	}
7556	case Type::STK_Bool:
7557	return CK_IntegralComplexToBoolean;
7558	case Type::STK_Floating:
7559	Src = ImpCastExprToType(E: Src.get(),
7560	Type: SrcTy->castAs<ComplexType>()->getElementType(),
7561	CK: CK_IntegralComplexToReal);
7562	return CK_IntegralToFloating;
7563	case Type::STK_CPointer:
7564	case Type::STK_ObjCObjectPointer:
7565	case Type::STK_BlockPointer:
7566	llvm_unreachable("valid complex int->pointer cast?");
7567	case Type::STK_MemberPointer:
7568	llvm_unreachable("member pointer type in C");
7569	case Type::STK_FixedPoint:
7570	Diag(Loc: Src.get()->getExprLoc(),
7571	DiagID: diag::err_unimplemented_conversion_with_fixed_point_type)
7572	<< SrcTy;
7573	return CK_IntegralCast;
7574	}
7575	llvm_unreachable("Should have returned before this");
7576	}
7577
7578	llvm_unreachable("Unhandled scalar cast");
7579	}
7580
7581	static bool breakDownVectorType(QualType type, uint64_t &len,
7582	QualType &eltType) {
7583	// Vectors are simple.
7584	if (const VectorType *vecType = type->getAs<VectorType>()) {
7585	len = vecType->getNumElements();
7586	eltType = vecType->getElementType();
7587	assert(eltType->isScalarType() || eltType->isMFloat8Type());
7588	return true;
7589	}
7590
7591	// We allow lax conversion to and from non-vector types, but only if
7592	// they're real types (i.e. non-complex, non-pointer scalar types).
7593	if (!type->isRealType()) return false;
7594
7595	len = 1;
7596	eltType = type;
7597	return true;
7598	}
7599
7600	bool Sema::isValidSveBitcast(QualType srcTy, QualType destTy) {
7601	assert(srcTy->isVectorType() || destTy->isVectorType());
7602
7603	auto ValidScalableConversion = [](QualType FirstType, QualType SecondType) {
7604	if (!FirstType->isSVESizelessBuiltinType())
7605	return false;
7606
7607	const auto *VecTy = SecondType->getAs<VectorType>();
7608	return VecTy && VecTy->getVectorKind() == VectorKind::SveFixedLengthData;
7609	};
7610
7611	return ValidScalableConversion(srcTy, destTy) ||
7612	ValidScalableConversion(destTy, srcTy);
7613	}
7614
7615	bool Sema::areMatrixTypesOfTheSameDimension(QualType srcTy, QualType destTy) {
7616	if (!destTy->isMatrixType() || !srcTy->isMatrixType())
7617	return false;
7618
7619	const ConstantMatrixType *matSrcType = srcTy->getAs<ConstantMatrixType>();
7620	const ConstantMatrixType *matDestType = destTy->getAs<ConstantMatrixType>();
7621
7622	return matSrcType->getNumRows() == matDestType->getNumRows() &&
7623	matSrcType->getNumColumns() == matDestType->getNumColumns();
7624	}
7625
7626	bool Sema::areVectorTypesSameSize(QualType SrcTy, QualType DestTy) {
7627	assert(DestTy->isVectorType() || SrcTy->isVectorType());
7628
7629	uint64_t SrcLen, DestLen;
7630	QualType SrcEltTy, DestEltTy;
7631	if (!breakDownVectorType(type: SrcTy, len&: SrcLen, eltType&: SrcEltTy))
7632	return false;
7633	if (!breakDownVectorType(type: DestTy, len&: DestLen, eltType&: DestEltTy))
7634	return false;
7635
7636	// ASTContext::getTypeSize will return the size rounded up to a
7637	// power of 2, so instead of using that, we need to use the raw
7638	// element size multiplied by the element count.
7639	uint64_t SrcEltSize = Context.getTypeSize(T: SrcEltTy);
7640	uint64_t DestEltSize = Context.getTypeSize(T: DestEltTy);
7641
7642	return (SrcLen * SrcEltSize == DestLen * DestEltSize);
7643	}
7644
7645	bool Sema::anyAltivecTypes(QualType SrcTy, QualType DestTy) {
7646	assert((DestTy->isVectorType() || SrcTy->isVectorType()) &&
7647	"expected at least one type to be a vector here");
7648
7649	bool IsSrcTyAltivec =
7650	SrcTy->isVectorType() && ((SrcTy->castAs<VectorType>()->getVectorKind() ==
7651	VectorKind::AltiVecVector) ||
7652	(SrcTy->castAs<VectorType>()->getVectorKind() ==
7653	VectorKind::AltiVecBool) ||
7654	(SrcTy->castAs<VectorType>()->getVectorKind() ==
7655	VectorKind::AltiVecPixel));
7656
7657	bool IsDestTyAltivec = DestTy->isVectorType() &&
7658	((DestTy->castAs<VectorType>()->getVectorKind() ==
7659	VectorKind::AltiVecVector) ||
7660	(DestTy->castAs<VectorType>()->getVectorKind() ==
7661	VectorKind::AltiVecBool) ||
7662	(DestTy->castAs<VectorType>()->getVectorKind() ==
7663	VectorKind::AltiVecPixel));
7664
7665	return (IsSrcTyAltivec || IsDestTyAltivec);
7666	}
7667
7668	bool Sema::areLaxCompatibleVectorTypes(QualType srcTy, QualType destTy) {
7669	assert(destTy->isVectorType() || srcTy->isVectorType());
7670
7671	// Disallow lax conversions between scalars and ExtVectors (these
7672	// conversions are allowed for other vector types because common headers
7673	// depend on them). Most scalar OP ExtVector cases are handled by the
7674	// splat path anyway, which does what we want (convert, not bitcast).
7675	// What this rules out for ExtVectors is crazy things like char4*float.
7676	if (srcTy->isScalarType() && destTy->isExtVectorType()) return false;
7677	if (destTy->isScalarType() && srcTy->isExtVectorType()) return false;
7678
7679	return areVectorTypesSameSize(SrcTy: srcTy, DestTy: destTy);
7680	}
7681
7682	bool Sema::isLaxVectorConversion(QualType srcTy, QualType destTy) {
7683	assert(destTy->isVectorType() || srcTy->isVectorType());
7684
7685	switch (Context.getLangOpts().getLaxVectorConversions()) {
7686	case LangOptions::LaxVectorConversionKind::None:
7687	return false;
7688
7689	case LangOptions::LaxVectorConversionKind::Integer:
7690	if (!srcTy->isIntegralOrEnumerationType()) {
7691	auto *Vec = srcTy->getAs<VectorType>();
7692	if (!Vec || !Vec->getElementType()->isIntegralOrEnumerationType())
7693	return false;
7694	}
7695	if (!destTy->isIntegralOrEnumerationType()) {
7696	auto *Vec = destTy->getAs<VectorType>();
7697	if (!Vec || !Vec->getElementType()->isIntegralOrEnumerationType())
7698	return false;
7699	}
7700	// OK, integer (vector) -> integer (vector) bitcast.
7701	break;
7702
7703	case LangOptions::LaxVectorConversionKind::All:
7704	break;
7705	}
7706
7707	return areLaxCompatibleVectorTypes(srcTy, destTy);
7708	}
7709
7710	bool Sema::CheckMatrixCast(SourceRange R, QualType DestTy, QualType SrcTy,
7711	CastKind &Kind) {
7712	if (SrcTy->isMatrixType() && DestTy->isMatrixType()) {
7713	if (!areMatrixTypesOfTheSameDimension(srcTy: SrcTy, destTy: DestTy)) {
7714	return Diag(Loc: R.getBegin(), DiagID: diag::err_invalid_conversion_between_matrixes)
7715	<< DestTy << SrcTy << R;
7716	}
7717	} else if (SrcTy->isMatrixType()) {
7718	return Diag(Loc: R.getBegin(),
7719	DiagID: diag::err_invalid_conversion_between_matrix_and_type)
7720	<< SrcTy << DestTy << R;
7721	} else if (DestTy->isMatrixType()) {
7722	return Diag(Loc: R.getBegin(),
7723	DiagID: diag::err_invalid_conversion_between_matrix_and_type)
7724	<< DestTy << SrcTy << R;
7725	}
7726
7727	Kind = CK_MatrixCast;
7728	return false;
7729	}
7730
7731	bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty,
7732	CastKind &Kind) {
7733	assert(VectorTy->isVectorType() && "Not a vector type!");
7734
7735	if (Ty->isVectorType() || Ty->isIntegralType(Ctx: Context)) {
7736	if (!areLaxCompatibleVectorTypes(srcTy: Ty, destTy: VectorTy))
7737	return Diag(Loc: R.getBegin(),
7738	DiagID: Ty->isVectorType() ?
7739	diag::err_invalid_conversion_between_vectors :
7740	diag::err_invalid_conversion_between_vector_and_integer)
7741	<< VectorTy << Ty << R;
7742	} else
7743	return Diag(Loc: R.getBegin(),
7744	DiagID: diag::err_invalid_conversion_between_vector_and_scalar)
7745	<< VectorTy << Ty << R;
7746
7747	Kind = CK_BitCast;
7748	return false;
7749	}
7750
7751	ExprResult Sema::prepareVectorSplat(QualType VectorTy, Expr *SplattedExpr) {
7752	QualType DestElemTy = VectorTy->castAs<VectorType>()->getElementType();
7753
7754	if (DestElemTy == SplattedExpr->getType())
7755	return SplattedExpr;
7756
7757	assert(DestElemTy->isFloatingType() ||
7758	DestElemTy->isIntegralOrEnumerationType());
7759
7760	CastKind CK;
7761	if (VectorTy->isExtVectorType() && SplattedExpr->getType()->isBooleanType()) {
7762	// OpenCL requires that we convert `true` boolean expressions to -1, but
7763	// only when splatting vectors.
7764	if (DestElemTy->isFloatingType()) {
7765	// To avoid having to have a CK_BooleanToSignedFloating cast kind, we cast
7766	// in two steps: boolean to signed integral, then to floating.
7767	ExprResult CastExprRes = ImpCastExprToType(E: SplattedExpr, Type: Context.IntTy,
7768	CK: CK_BooleanToSignedIntegral);
7769	SplattedExpr = CastExprRes.get();
7770	CK = CK_IntegralToFloating;
7771	} else {
7772	CK = CK_BooleanToSignedIntegral;
7773	}
7774	} else {
7775	ExprResult CastExprRes = SplattedExpr;
7776	CK = PrepareScalarCast(Src&: CastExprRes, DestTy: DestElemTy);
7777	if (CastExprRes.isInvalid())
7778	return ExprError();
7779	SplattedExpr = CastExprRes.get();
7780	}
7781	return ImpCastExprToType(E: SplattedExpr, Type: DestElemTy, CK);
7782	}
7783
7784	ExprResult Sema::CheckExtVectorCast(SourceRange R, QualType DestTy,
7785	Expr *CastExpr, CastKind &Kind) {
7786	assert(DestTy->isExtVectorType() && "Not an extended vector type!");
7787
7788	QualType SrcTy = CastExpr->getType();
7789
7790	// If SrcTy is a VectorType, the total size must match to explicitly cast to
7791	// an ExtVectorType.
7792	// In OpenCL, casts between vectors of different types are not allowed.
7793	// (See OpenCL 6.2).
7794	if (SrcTy->isVectorType()) {
7795	if (!areLaxCompatibleVectorTypes(srcTy: SrcTy, destTy: DestTy) ||
7796	(getLangOpts().OpenCL &&
7797	!Context.hasSameUnqualifiedType(T1: DestTy, T2: SrcTy))) {
7798	Diag(Loc: R.getBegin(),DiagID: diag::err_invalid_conversion_between_ext_vectors)
7799	<< DestTy << SrcTy << R;
7800	return ExprError();
7801	}
7802	Kind = CK_BitCast;
7803	return CastExpr;
7804	}
7805
7806	// All non-pointer scalars can be cast to ExtVector type. The appropriate
7807	// conversion will take place first from scalar to elt type, and then
7808	// splat from elt type to vector.
7809	if (SrcTy->isPointerType())
7810	return Diag(Loc: R.getBegin(),
7811	DiagID: diag::err_invalid_conversion_between_vector_and_scalar)
7812	<< DestTy << SrcTy << R;
7813
7814	Kind = CK_VectorSplat;
7815	return prepareVectorSplat(VectorTy: DestTy, SplattedExpr: CastExpr);
7816	}
7817
7818	ExprResult
7819	Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc,
7820	Declarator &D, ParsedType &Ty,
7821	SourceLocation RParenLoc, Expr *CastExpr) {
7822	assert(!D.isInvalidType() && (CastExpr != nullptr) &&
7823	"ActOnCastExpr(): missing type or expr");
7824
7825	TypeSourceInfo *castTInfo = GetTypeForDeclaratorCast(D, FromTy: CastExpr->getType());
7826	if (D.isInvalidType())
7827	return ExprError();
7828
7829	if (getLangOpts().CPlusPlus) {
7830	// Check that there are no default arguments (C++ only).
7831	CheckExtraCXXDefaultArguments(D);
7832	}
7833
7834	checkUnusedDeclAttributes(D);
7835
7836	QualType castType = castTInfo->getType();
7837	Ty = CreateParsedType(T: castType, TInfo: castTInfo);
7838
7839	bool isVectorLiteral = false;
7840
7841	// Check for an altivec or OpenCL literal,
7842	// i.e. all the elements are integer constants.
7843	ParenExpr *PE = dyn_cast<ParenExpr>(Val: CastExpr);
7844	ParenListExpr *PLE = dyn_cast<ParenListExpr>(Val: CastExpr);
7845	if ((getLangOpts().AltiVec || getLangOpts().ZVector || getLangOpts().OpenCL)
7846	&& castType->isVectorType() && (PE || PLE)) {
7847	if (PLE && PLE->getNumExprs() == 0) {
7848	Diag(Loc: PLE->getExprLoc(), DiagID: diag::err_altivec_empty_initializer);
7849	return ExprError();
7850	}
7851	if (PE || PLE->getNumExprs() == 1) {
7852	Expr *E = (PE ? PE->getSubExpr() : PLE->getExpr(Init: 0));
7853	if (!E->isTypeDependent() && !E->getType()->isVectorType())
7854	isVectorLiteral = true;
7855	}
7856	else
7857	isVectorLiteral = true;
7858	}
7859
7860	// If this is a vector initializer, '(' type ')' '(' init, ..., init ')'
7861	// then handle it as such.
7862	if (isVectorLiteral)
7863	return BuildVectorLiteral(LParenLoc, RParenLoc, E: CastExpr, TInfo: castTInfo);
7864
7865	// If the Expr being casted is a ParenListExpr, handle it specially.
7866	// This is not an AltiVec-style cast, so turn the ParenListExpr into a
7867	// sequence of BinOp comma operators.
7868	if (isa<ParenListExpr>(Val: CastExpr)) {
7869	ExprResult Result = MaybeConvertParenListExprToParenExpr(S, ME: CastExpr);
7870	if (Result.isInvalid()) return ExprError();
7871	CastExpr = Result.get();
7872	}
7873
7874	if (getLangOpts().CPlusPlus && !castType->isVoidType())
7875	Diag(Loc: LParenLoc, DiagID: diag::warn_old_style_cast) << CastExpr->getSourceRange();
7876
7877	ObjC().CheckTollFreeBridgeCast(castType, castExpr: CastExpr);
7878
7879	ObjC().CheckObjCBridgeRelatedCast(castType, castExpr: CastExpr);
7880
7881	DiscardMisalignedMemberAddress(T: castType.getTypePtr(), E: CastExpr);
7882
7883	return BuildCStyleCastExpr(LParenLoc, Ty: castTInfo, RParenLoc, Op: CastExpr);
7884	}
7885
7886	ExprResult Sema::BuildVectorLiteral(SourceLocation LParenLoc,
7887	SourceLocation RParenLoc, Expr *E,
7888	TypeSourceInfo *TInfo) {
7889	assert((isa<ParenListExpr>(E) || isa<ParenExpr>(E)) &&
7890	"Expected paren or paren list expression");
7891
7892	Expr **exprs;
7893	unsigned numExprs;
7894	Expr *subExpr;
7895	SourceLocation LiteralLParenLoc, LiteralRParenLoc;
7896	if (ParenListExpr *PE = dyn_cast<ParenListExpr>(Val: E)) {
7897	LiteralLParenLoc = PE->getLParenLoc();
7898	LiteralRParenLoc = PE->getRParenLoc();
7899	exprs = PE->getExprs();
7900	numExprs = PE->getNumExprs();
7901	} else { // isa<ParenExpr> by assertion at function entrance
7902	LiteralLParenLoc = cast<ParenExpr>(Val: E)->getLParen();
7903	LiteralRParenLoc = cast<ParenExpr>(Val: E)->getRParen();
7904	subExpr = cast<ParenExpr>(Val: E)->getSubExpr();
7905	exprs = &subExpr;
7906	numExprs = 1;
7907	}
7908
7909	QualType Ty = TInfo->getType();
7910	assert(Ty->isVectorType() && "Expected vector type");
7911
7912	SmallVector<Expr *, 8> initExprs;
7913	const VectorType *VTy = Ty->castAs<VectorType>();
7914	unsigned numElems = VTy->getNumElements();
7915
7916	// '(...)' form of vector initialization in AltiVec: the number of
7917	// initializers must be one or must match the size of the vector.
7918	// If a single value is specified in the initializer then it will be
7919	// replicated to all the components of the vector
7920	if (CheckAltivecInitFromScalar(R: E->getSourceRange(), VecTy: Ty,
7921	SrcTy: VTy->getElementType()))
7922	return ExprError();
7923	if (ShouldSplatAltivecScalarInCast(VecTy: VTy)) {
7924	// The number of initializers must be one or must match the size of the
7925	// vector. If a single value is specified in the initializer then it will
7926	// be replicated to all the components of the vector
7927	if (numExprs == 1) {
7928	QualType ElemTy = VTy->getElementType();
7929	ExprResult Literal = DefaultLvalueConversion(E: exprs[0]);
7930	if (Literal.isInvalid())
7931	return ExprError();
7932	Literal = ImpCastExprToType(E: Literal.get(), Type: ElemTy,
7933	CK: PrepareScalarCast(Src&: Literal, DestTy: ElemTy));
7934	return BuildCStyleCastExpr(LParenLoc, Ty: TInfo, RParenLoc, Op: Literal.get());
7935	}
7936	else if (numExprs < numElems) {
7937	Diag(Loc: E->getExprLoc(),
7938	DiagID: diag::err_incorrect_number_of_vector_initializers);
7939	return ExprError();
7940	}
7941	else
7942	initExprs.append(in_start: exprs, in_end: exprs + numExprs);
7943	}
7944	else {
7945	// For OpenCL, when the number of initializers is a single value,
7946	// it will be replicated to all components of the vector.
7947	if (getLangOpts().OpenCL && VTy->getVectorKind() == VectorKind::Generic &&
7948	numExprs == 1) {
7949	QualType ElemTy = VTy->getElementType();
7950	ExprResult Literal = DefaultLvalueConversion(E: exprs[0]);
7951	if (Literal.isInvalid())
7952	return ExprError();
7953	Literal = ImpCastExprToType(E: Literal.get(), Type: ElemTy,
7954	CK: PrepareScalarCast(Src&: Literal, DestTy: ElemTy));
7955	return BuildCStyleCastExpr(LParenLoc, Ty: TInfo, RParenLoc, Op: Literal.get());
7956	}
7957
7958	initExprs.append(in_start: exprs, in_end: exprs + numExprs);
7959	}
7960	// FIXME: This means that pretty-printing the final AST will produce curly
7961	// braces instead of the original commas.
7962	InitListExpr *initE = new (Context) InitListExpr(Context, LiteralLParenLoc,
7963	initExprs, LiteralRParenLoc);
7964	initE->setType(Ty);
7965	return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, LiteralExpr: initE);
7966	}
7967
7968	ExprResult
7969	Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *OrigExpr) {
7970	ParenListExpr *E = dyn_cast<ParenListExpr>(Val: OrigExpr);
7971	if (!E)
7972	return OrigExpr;
7973
7974	ExprResult Result(E->getExpr(Init: 0));
7975
7976	for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i)
7977	Result = ActOnBinOp(S, TokLoc: E->getExprLoc(), Kind: tok::comma, LHSExpr: Result.get(),
7978	RHSExpr: E->getExpr(Init: i));
7979
7980	if (Result.isInvalid()) return ExprError();
7981
7982	return ActOnParenExpr(L: E->getLParenLoc(), R: E->getRParenLoc(), E: Result.get());
7983	}
7984
7985	ExprResult Sema::ActOnParenListExpr(SourceLocation L,
7986	SourceLocation R,
7987	MultiExprArg Val) {
7988	return ParenListExpr::Create(Ctx: Context, LParenLoc: L, Exprs: Val, RParenLoc: R);
7989	}
7990
7991	ExprResult Sema::ActOnCXXParenListInitExpr(ArrayRef<Expr *> Args, QualType T,
7992	unsigned NumUserSpecifiedExprs,
7993	SourceLocation InitLoc,
7994	SourceLocation LParenLoc,
7995	SourceLocation RParenLoc) {
7996	return CXXParenListInitExpr::Create(C&: Context, Args, T, NumUserSpecifiedExprs,
7997	InitLoc, LParenLoc, RParenLoc);
7998	}
7999
8000	bool Sema::DiagnoseConditionalForNull(const Expr *LHSExpr, const Expr *RHSExpr,
8001	SourceLocation QuestionLoc) {
8002	const Expr *NullExpr = LHSExpr;
8003	const Expr *NonPointerExpr = RHSExpr;
8004	Expr::NullPointerConstantKind NullKind =
8005	NullExpr->isNullPointerConstant(Ctx&: Context,
8006	NPC: Expr::NPC_ValueDependentIsNotNull);
8007
8008	if (NullKind == Expr::NPCK_NotNull) {
8009	NullExpr = RHSExpr;
8010	NonPointerExpr = LHSExpr;
8011	NullKind =
8012	NullExpr->isNullPointerConstant(Ctx&: Context,
8013	NPC: Expr::NPC_ValueDependentIsNotNull);
8014	}
8015
8016	if (NullKind == Expr::NPCK_NotNull)
8017	return false;
8018
8019	if (NullKind == Expr::NPCK_ZeroExpression)
8020	return false;
8021
8022	if (NullKind == Expr::NPCK_ZeroLiteral) {
8023	// In this case, check to make sure that we got here from a "NULL"
8024	// string in the source code.
8025	NullExpr = NullExpr->IgnoreParenImpCasts();
8026	SourceLocation loc = NullExpr->getExprLoc();
8027	if (!findMacroSpelling(loc, name: "NULL"))
8028	return false;
8029	}
8030
8031	int DiagType = (NullKind == Expr::NPCK_CXX11_nullptr);
8032	Diag(Loc: QuestionLoc, DiagID: diag::err_typecheck_cond_incompatible_operands_null)
8033	<< NonPointerExpr->getType() << DiagType
8034	<< NonPointerExpr->getSourceRange();
8035	return true;
8036	}
8037
8038	/// Return false if the condition expression is valid, true otherwise.
8039	static bool checkCondition(Sema &S, const Expr *Cond,
8040	SourceLocation QuestionLoc) {
8041	QualType CondTy = Cond->getType();
8042
8043	// OpenCL v1.1 s6.3.i says the condition cannot be a floating point type.
8044	if (S.getLangOpts().OpenCL && CondTy->isFloatingType()) {
8045	S.Diag(Loc: QuestionLoc, DiagID: diag::err_typecheck_cond_expect_nonfloat)
8046	<< CondTy << Cond->getSourceRange();
8047	return true;
8048	}
8049
8050	// C99 6.5.15p2
8051	if (CondTy->isScalarType()) return false;
8052
8053	S.Diag(Loc: QuestionLoc, DiagID: diag::err_typecheck_cond_expect_scalar)
8054	<< CondTy << Cond->getSourceRange();
8055	return true;
8056	}
8057
8058	/// Return false if the NullExpr can be promoted to PointerTy,
8059	/// true otherwise.
8060	static bool checkConditionalNullPointer(Sema &S, ExprResult &NullExpr,
8061	QualType PointerTy) {
8062	if ((!PointerTy->isAnyPointerType() && !PointerTy->isBlockPointerType()) ||
8063	!NullExpr.get()->isNullPointerConstant(Ctx&: S.Context,
8064	NPC: Expr::NPC_ValueDependentIsNull))
8065	return true;
8066
8067	NullExpr = S.ImpCastExprToType(E: NullExpr.get(), Type: PointerTy, CK: CK_NullToPointer);
8068	return false;
8069	}
8070
8071	/// Checks compatibility between two pointers and return the resulting
8072	/// type.
8073	static QualType checkConditionalPointerCompatibility(Sema &S, ExprResult &LHS,
8074	ExprResult &RHS,
8075	SourceLocation Loc) {
8076	QualType LHSTy = LHS.get()->getType();
8077	QualType RHSTy = RHS.get()->getType();
8078
8079	if (S.Context.hasSameType(T1: LHSTy, T2: RHSTy)) {
8080	// Two identical pointers types are always compatible.
8081	return S.Context.getCommonSugaredType(X: LHSTy, Y: RHSTy);
8082	}
8083
8084	QualType lhptee, rhptee;
8085
8086	// Get the pointee types.
8087	bool IsBlockPointer = false;
8088	if (const BlockPointerType *LHSBTy = LHSTy->getAs<BlockPointerType>()) {
8089	lhptee = LHSBTy->getPointeeType();
8090	rhptee = RHSTy->castAs<BlockPointerType>()->getPointeeType();
8091	IsBlockPointer = true;
8092	} else {
8093	lhptee = LHSTy->castAs<PointerType>()->getPointeeType();
8094	rhptee = RHSTy->castAs<PointerType>()->getPointeeType();
8095	}
8096
8097	// C99 6.5.15p6: If both operands are pointers to compatible types or to
8098	// differently qualified versions of compatible types, the result type is
8099	// a pointer to an appropriately qualified version of the composite
8100	// type.
8101
8102	// Only CVR-qualifiers exist in the standard, and the differently-qualified
8103	// clause doesn't make sense for our extensions. E.g. address space 2 should
8104	// be incompatible with address space 3: they may live on different devices or
8105	// anything.
8106	Qualifiers lhQual = lhptee.getQualifiers();
8107	Qualifiers rhQual = rhptee.getQualifiers();
8108
8109	LangAS ResultAddrSpace = LangAS::Default;
8110	LangAS LAddrSpace = lhQual.getAddressSpace();
8111	LangAS RAddrSpace = rhQual.getAddressSpace();
8112
8113	// OpenCL v1.1 s6.5 - Conversion between pointers to distinct address
8114	// spaces is disallowed.
8115	if (lhQual.isAddressSpaceSupersetOf(other: rhQual, Ctx: S.getASTContext()))
8116	ResultAddrSpace = LAddrSpace;
8117	else if (rhQual.isAddressSpaceSupersetOf(other: lhQual, Ctx: S.getASTContext()))
8118	ResultAddrSpace = RAddrSpace;
8119	else {
8120	S.Diag(Loc, DiagID: diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
8121	<< LHSTy << RHSTy << 2 << LHS.get()->getSourceRange()
8122	<< RHS.get()->getSourceRange();
8123	return QualType();
8124	}
8125
8126	unsigned MergedCVRQual = lhQual.getCVRQualifiers() | rhQual.getCVRQualifiers();
8127	auto LHSCastKind = CK_BitCast, RHSCastKind = CK_BitCast;
8128	lhQual.removeCVRQualifiers();
8129	rhQual.removeCVRQualifiers();
8130
8131	if (!lhQual.getPointerAuth().isEquivalent(Other: rhQual.getPointerAuth())) {
8132	S.Diag(Loc, DiagID: diag::err_typecheck_cond_incompatible_ptrauth)
8133	<< LHSTy << RHSTy << LHS.get()->getSourceRange()
8134	<< RHS.get()->getSourceRange();
8135	return QualType();
8136	}
8137
8138	// OpenCL v2.0 specification doesn't extend compatibility of type qualifiers
8139	// (C99 6.7.3) for address spaces. We assume that the check should behave in
8140	// the same manner as it's defined for CVR qualifiers, so for OpenCL two
8141	// qual types are compatible iff
8142	// * corresponded types are compatible
8143	// * CVR qualifiers are equal
8144	// * address spaces are equal
8145	// Thus for conditional operator we merge CVR and address space unqualified
8146	// pointees and if there is a composite type we return a pointer to it with
8147	// merged qualifiers.
8148	LHSCastKind =
8149	LAddrSpace == ResultAddrSpace ? CK_BitCast : CK_AddressSpaceConversion;
8150	RHSCastKind =
8151	RAddrSpace == ResultAddrSpace ? CK_BitCast : CK_AddressSpaceConversion;
8152	lhQual.removeAddressSpace();
8153	rhQual.removeAddressSpace();
8154
8155	lhptee = S.Context.getQualifiedType(T: lhptee.getUnqualifiedType(), Qs: lhQual);
8156	rhptee = S.Context.getQualifiedType(T: rhptee.getUnqualifiedType(), Qs: rhQual);
8157
8158	QualType CompositeTy = S.Context.mergeTypes(
8159	lhptee, rhptee, /*OfBlockPointer=*/false, /*Unqualified=*/false,
8160	/*BlockReturnType=*/false, /*IsConditionalOperator=*/true);
8161
8162	if (CompositeTy.isNull()) {
8163	// In this situation, we assume void* type. No especially good
8164	// reason, but this is what gcc does, and we do have to pick
8165	// to get a consistent AST.
8166	QualType incompatTy;
8167	incompatTy = S.Context.getPointerType(
8168	T: S.Context.getAddrSpaceQualType(T: S.Context.VoidTy, AddressSpace: ResultAddrSpace));
8169	LHS = S.ImpCastExprToType(E: LHS.get(), Type: incompatTy, CK: LHSCastKind);
8170	RHS = S.ImpCastExprToType(E: RHS.get(), Type: incompatTy, CK: RHSCastKind);
8171
8172	// FIXME: For OpenCL the warning emission and cast to void* leaves a room
8173	// for casts between types with incompatible address space qualifiers.
8174	// For the following code the compiler produces casts between global and
8175	// local address spaces of the corresponded innermost pointees:
8176	// local int *global *a;
8177	// global int *global *b;
8178	// a = (0 ? a : b); // see C99 6.5.16.1.p1.
8179	S.Diag(Loc, DiagID: diag::ext_typecheck_cond_incompatible_pointers)
8180	<< LHSTy << RHSTy << LHS.get()->getSourceRange()
8181	<< RHS.get()->getSourceRange();
8182
8183	return incompatTy;
8184	}
8185
8186	// The pointer types are compatible.
8187	// In case of OpenCL ResultTy should have the address space qualifier
8188	// which is a superset of address spaces of both the 2nd and the 3rd
8189	// operands of the conditional operator.
8190	QualType ResultTy = [&, ResultAddrSpace]() {
8191	if (S.getLangOpts().OpenCL) {
8192	Qualifiers CompositeQuals = CompositeTy.getQualifiers();
8193	CompositeQuals.setAddressSpace(ResultAddrSpace);
8194	return S.Context
8195	.getQualifiedType(T: CompositeTy.getUnqualifiedType(), Qs: CompositeQuals)
8196	.withCVRQualifiers(CVR: MergedCVRQual);
8197	}
8198	return CompositeTy.withCVRQualifiers(CVR: MergedCVRQual);
8199	}();
8200	if (IsBlockPointer)
8201	ResultTy = S.Context.getBlockPointerType(T: ResultTy);
8202	else
8203	ResultTy = S.Context.getPointerType(T: ResultTy);
8204
8205	LHS = S.ImpCastExprToType(E: LHS.get(), Type: ResultTy, CK: LHSCastKind);
8206	RHS = S.ImpCastExprToType(E: RHS.get(), Type: ResultTy, CK: RHSCastKind);
8207	return ResultTy;
8208	}
8209
8210	/// Return the resulting type when the operands are both block pointers.
8211	static QualType checkConditionalBlockPointerCompatibility(Sema &S,
8212	ExprResult &LHS,
8213	ExprResult &RHS,
8214	SourceLocation Loc) {
8215	QualType LHSTy = LHS.get()->getType();
8216	QualType RHSTy = RHS.get()->getType();
8217
8218	if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) {
8219	if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) {
8220	QualType destType = S.Context.getPointerType(T: S.Context.VoidTy);
8221	LHS = S.ImpCastExprToType(E: LHS.get(), Type: destType, CK: CK_BitCast);
8222	RHS = S.ImpCastExprToType(E: RHS.get(), Type: destType, CK: CK_BitCast);
8223	return destType;
8224	}
8225	S.Diag(Loc, DiagID: diag::err_typecheck_cond_incompatible_operands)
8226	<< LHSTy << RHSTy << LHS.get()->getSourceRange()
8227	<< RHS.get()->getSourceRange();
8228	return QualType();
8229	}
8230
8231	// We have 2 block pointer types.
8232	return checkConditionalPointerCompatibility(S, LHS, RHS, Loc);
8233	}
8234
8235	/// Return the resulting type when the operands are both pointers.
8236	static QualType
8237	checkConditionalObjectPointersCompatibility(Sema &S, ExprResult &LHS,
8238	ExprResult &RHS,
8239	SourceLocation Loc) {
8240	// get the pointer types
8241	QualType LHSTy = LHS.get()->getType();
8242	QualType RHSTy = RHS.get()->getType();
8243
8244	// get the "pointed to" types
8245	QualType lhptee = LHSTy->castAs<PointerType>()->getPointeeType();
8246	QualType rhptee = RHSTy->castAs<PointerType>()->getPointeeType();
8247
8248	// ignore qualifiers on void (C99 6.5.15p3, clause 6)
8249	if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) {
8250	// Figure out necessary qualifiers (C99 6.5.15p6)
8251	QualType destPointee
8252	= S.Context.getQualifiedType(T: lhptee, Qs: rhptee.getQualifiers());
8253	QualType destType = S.Context.getPointerType(T: destPointee);
8254	// Add qualifiers if necessary.
8255	LHS = S.ImpCastExprToType(E: LHS.get(), Type: destType, CK: CK_NoOp);
8256	// Promote to void*.
8257	RHS = S.ImpCastExprToType(E: RHS.get(), Type: destType, CK: CK_BitCast);
8258	return destType;
8259	}
8260	if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) {
8261	QualType destPointee
8262	= S.Context.getQualifiedType(T: rhptee, Qs: lhptee.getQualifiers());
8263	QualType destType = S.Context.getPointerType(T: destPointee);
8264	// Add qualifiers if necessary.
8265	RHS = S.ImpCastExprToType(E: RHS.get(), Type: destType, CK: CK_NoOp);
8266	// Promote to void*.
8267	LHS = S.ImpCastExprToType(E: LHS.get(), Type: destType, CK: CK_BitCast);
8268	return destType;
8269	}
8270
8271	return checkConditionalPointerCompatibility(S, LHS, RHS, Loc);
8272	}
8273
8274	/// Return false if the first expression is not an integer and the second
8275	/// expression is not a pointer, true otherwise.
8276	static bool checkPointerIntegerMismatch(Sema &S, ExprResult &Int,
8277	Expr* PointerExpr, SourceLocation Loc,
8278	bool IsIntFirstExpr) {
8279	if (!PointerExpr->getType()->isPointerType() ||
8280	!Int.get()->getType()->isIntegerType())
8281	return false;
8282
8283	Expr *Expr1 = IsIntFirstExpr ? Int.get() : PointerExpr;
8284	Expr *Expr2 = IsIntFirstExpr ? PointerExpr : Int.get();
8285
8286	S.Diag(Loc, DiagID: diag::ext_typecheck_cond_pointer_integer_mismatch)
8287	<< Expr1->getType() << Expr2->getType()
8288	<< Expr1->getSourceRange() << Expr2->getSourceRange();
8289	Int = S.ImpCastExprToType(E: Int.get(), Type: PointerExpr->getType(),
8290	CK: CK_IntegralToPointer);
8291	return true;
8292	}
8293
8294	/// Simple conversion between integer and floating point types.
8295	///
8296	/// Used when handling the OpenCL conditional operator where the
8297	/// condition is a vector while the other operands are scalar.
8298	///
8299	/// OpenCL v1.1 s6.3.i and s6.11.6 together require that the scalar
8300	/// types are either integer or floating type. Between the two
8301	/// operands, the type with the higher rank is defined as the "result
8302	/// type". The other operand needs to be promoted to the same type. No
8303	/// other type promotion is allowed. We cannot use
8304	/// UsualArithmeticConversions() for this purpose, since it always
8305	/// promotes promotable types.
8306	static QualType OpenCLArithmeticConversions(Sema &S, ExprResult &LHS,
8307	ExprResult &RHS,
8308	SourceLocation QuestionLoc) {
8309	LHS = S.DefaultFunctionArrayLvalueConversion(E: LHS.get());
8310	if (LHS.isInvalid())
8311	return QualType();
8312	RHS = S.DefaultFunctionArrayLvalueConversion(E: RHS.get());
8313	if (RHS.isInvalid())
8314	return QualType();
8315
8316	// For conversion purposes, we ignore any qualifiers.
8317	// For example, "const float" and "float" are equivalent.
8318	QualType LHSType =
8319	S.Context.getCanonicalType(T: LHS.get()->getType()).getUnqualifiedType();
8320	QualType RHSType =
8321	S.Context.getCanonicalType(T: RHS.get()->getType()).getUnqualifiedType();
8322
8323	if (!LHSType->isIntegerType() && !LHSType->isRealFloatingType()) {
8324	S.Diag(Loc: QuestionLoc, DiagID: diag::err_typecheck_cond_expect_int_float)
8325	<< LHSType << LHS.get()->getSourceRange();
8326	return QualType();
8327	}
8328
8329	if (!RHSType->isIntegerType() && !RHSType->isRealFloatingType()) {
8330	S.Diag(Loc: QuestionLoc, DiagID: diag::err_typecheck_cond_expect_int_float)
8331	<< RHSType << RHS.get()->getSourceRange();
8332	return QualType();
8333	}
8334
8335	// If both types are identical, no conversion is needed.
8336	if (LHSType == RHSType)
8337	return LHSType;
8338
8339	// Now handle "real" floating types (i.e. float, double, long double).
8340	if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType())
8341	return handleFloatConversion(S, LHS, RHS, LHSType, RHSType,
8342	/*IsCompAssign = */ false);
8343
8344	// Finally, we have two differing integer types.
8345	return handleIntegerConversion<doIntegralCast, doIntegralCast>
8346	(S, LHS, RHS, LHSType, RHSType, /*IsCompAssign = */ false);
8347	}
8348
8349	/// Convert scalar operands to a vector that matches the
8350	/// condition in length.
8351	///
8352	/// Used when handling the OpenCL conditional operator where the
8353	/// condition is a vector while the other operands are scalar.
8354	///
8355	/// We first compute the "result type" for the scalar operands
8356	/// according to OpenCL v1.1 s6.3.i. Both operands are then converted
8357	/// into a vector of that type where the length matches the condition
8358	/// vector type. s6.11.6 requires that the element types of the result
8359	/// and the condition must have the same number of bits.
8360	static QualType
8361	OpenCLConvertScalarsToVectors(Sema &S, ExprResult &LHS, ExprResult &RHS,
8362	QualType CondTy, SourceLocation QuestionLoc) {
8363	QualType ResTy = OpenCLArithmeticConversions(S, LHS, RHS, QuestionLoc);
8364	if (ResTy.isNull()) return QualType();
8365
8366	const VectorType *CV = CondTy->getAs<VectorType>();
8367	assert(CV);
8368
8369	// Determine the vector result type
8370	unsigned NumElements = CV->getNumElements();
8371	QualType VectorTy = S.Context.getExtVectorType(VectorType: ResTy, NumElts: NumElements);
8372
8373	// Ensure that all types have the same number of bits
8374	if (S.Context.getTypeSize(T: CV->getElementType())
8375	!= S.Context.getTypeSize(T: ResTy)) {
8376	// Since VectorTy is created internally, it does not pretty print
8377	// with an OpenCL name. Instead, we just print a description.
8378	std::string EleTyName = ResTy.getUnqualifiedType().getAsString();
8379	SmallString<64> Str;
8380	llvm::raw_svector_ostream OS(Str);
8381	OS << "(vector of " << NumElements << " '" << EleTyName << "' values)";
8382	S.Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_element_size)
8383	<< CondTy << OS.str();
8384	return QualType();
8385	}
8386
8387	// Convert operands to the vector result type
8388	LHS = S.ImpCastExprToType(E: LHS.get(), Type: VectorTy, CK: CK_VectorSplat);
8389	RHS = S.ImpCastExprToType(E: RHS.get(), Type: VectorTy, CK: CK_VectorSplat);
8390
8391	return VectorTy;
8392	}
8393
8394	/// Return false if this is a valid OpenCL condition vector
8395	static bool checkOpenCLConditionVector(Sema &S, Expr *Cond,
8396	SourceLocation QuestionLoc) {
8397	// OpenCL v1.1 s6.11.6 says the elements of the vector must be of
8398	// integral type.
8399	const VectorType *CondTy = Cond->getType()->getAs<VectorType>();
8400	assert(CondTy);
8401	QualType EleTy = CondTy->getElementType();
8402	if (EleTy->isIntegerType()) return false;
8403
8404	S.Diag(Loc: QuestionLoc, DiagID: diag::err_typecheck_cond_expect_nonfloat)
8405	<< Cond->getType() << Cond->getSourceRange();
8406	return true;
8407	}
8408
8409	/// Return false if the vector condition type and the vector
8410	/// result type are compatible.
8411	///
8412	/// OpenCL v1.1 s6.11.6 requires that both vector types have the same
8413	/// number of elements, and their element types have the same number
8414	/// of bits.
8415	static bool checkVectorResult(Sema &S, QualType CondTy, QualType VecResTy,
8416	SourceLocation QuestionLoc) {
8417	const VectorType *CV = CondTy->getAs<VectorType>();
8418	const VectorType *RV = VecResTy->getAs<VectorType>();
8419	assert(CV && RV);
8420
8421	if (CV->getNumElements() != RV->getNumElements()) {
8422	S.Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_size)
8423	<< CondTy << VecResTy;
8424	return true;
8425	}
8426
8427	QualType CVE = CV->getElementType();
8428	QualType RVE = RV->getElementType();
8429
8430	if (S.Context.getTypeSize(T: CVE) != S.Context.getTypeSize(T: RVE)) {
8431	S.Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_element_size)
8432	<< CondTy << VecResTy;
8433	return true;
8434	}
8435
8436	return false;
8437	}
8438
8439	/// Return the resulting type for the conditional operator in
8440	/// OpenCL (aka "ternary selection operator", OpenCL v1.1
8441	/// s6.3.i) when the condition is a vector type.
8442	static QualType
8443	OpenCLCheckVectorConditional(Sema &S, ExprResult &Cond,
8444	ExprResult &LHS, ExprResult &RHS,
8445	SourceLocation QuestionLoc) {
8446	Cond = S.DefaultFunctionArrayLvalueConversion(E: Cond.get());
8447	if (Cond.isInvalid())
8448	return QualType();
8449	QualType CondTy = Cond.get()->getType();
8450
8451	if (checkOpenCLConditionVector(S, Cond: Cond.get(), QuestionLoc))
8452	return QualType();
8453
8454	// If either operand is a vector then find the vector type of the
8455	// result as specified in OpenCL v1.1 s6.3.i.
8456	if (LHS.get()->getType()->isVectorType() ||
8457	RHS.get()->getType()->isVectorType()) {
8458	bool IsBoolVecLang =
8459	!S.getLangOpts().OpenCL && !S.getLangOpts().OpenCLCPlusPlus;
8460	QualType VecResTy =
8461	S.CheckVectorOperands(LHS, RHS, Loc: QuestionLoc,
8462	/*isCompAssign*/ IsCompAssign: false,
8463	/*AllowBothBool*/ true,
8464	/*AllowBoolConversions*/ AllowBoolConversion: false,
8465	/*AllowBooleanOperation*/ AllowBoolOperation: IsBoolVecLang,
8466	/*ReportInvalid*/ true);
8467	if (VecResTy.isNull())
8468	return QualType();
8469	// The result type must match the condition type as specified in
8470	// OpenCL v1.1 s6.11.6.
8471	if (checkVectorResult(S, CondTy, VecResTy, QuestionLoc))
8472	return QualType();
8473	return VecResTy;
8474	}
8475
8476	// Both operands are scalar.
8477	return OpenCLConvertScalarsToVectors(S, LHS, RHS, CondTy, QuestionLoc);
8478	}
8479
8480	/// Return true if the Expr is block type
8481	static bool checkBlockType(Sema &S, const Expr *E) {
8482	if (E->getType()->isBlockPointerType()) {
8483	S.Diag(Loc: E->getExprLoc(), DiagID: diag::err_opencl_ternary_with_block);
8484	return true;
8485	}
8486
8487	if (const CallExpr *CE = dyn_cast<CallExpr>(Val: E)) {
8488	QualType Ty = CE->getCallee()->getType();
8489	if (Ty->isBlockPointerType()) {
8490	S.Diag(Loc: E->getExprLoc(), DiagID: diag::err_opencl_ternary_with_block);
8491	return true;
8492	}
8493	}
8494	return false;
8495	}
8496
8497	/// Note that LHS is not null here, even if this is the gnu "x ?: y" extension.
8498	/// In that case, LHS = cond.
8499	/// C99 6.5.15
8500	QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
8501	ExprResult &RHS, ExprValueKind &VK,
8502	ExprObjectKind &OK,
8503	SourceLocation QuestionLoc) {
8504
8505	ExprResult LHSResult = CheckPlaceholderExpr(E: LHS.get());
8506	if (!LHSResult.isUsable()) return QualType();
8507	LHS = LHSResult;
8508
8509	ExprResult RHSResult = CheckPlaceholderExpr(E: RHS.get());
8510	if (!RHSResult.isUsable()) return QualType();
8511	RHS = RHSResult;
8512
8513	// C++ is sufficiently different to merit its own checker.
8514	if (getLangOpts().CPlusPlus)
8515	return CXXCheckConditionalOperands(cond&: Cond, lhs&: LHS, rhs&: RHS, VK, OK, questionLoc: QuestionLoc);
8516
8517	VK = VK_PRValue;
8518	OK = OK_Ordinary;
8519
8520	if (Context.isDependenceAllowed() &&
8521	(Cond.get()->isTypeDependent() || LHS.get()->isTypeDependent() ||
8522	RHS.get()->isTypeDependent())) {
8523	assert(!getLangOpts().CPlusPlus);
8524	assert((Cond.get()->containsErrors() || LHS.get()->containsErrors() ||
8525	RHS.get()->containsErrors()) &&
8526	"should only occur in error-recovery path.");
8527	return Context.DependentTy;
8528	}
8529
8530	// The OpenCL operator with a vector condition is sufficiently
8531	// different to merit its own checker.
8532	if ((getLangOpts().OpenCL && Cond.get()->getType()->isVectorType()) ||
8533	Cond.get()->getType()->isExtVectorType())
8534	return OpenCLCheckVectorConditional(S&: *this, Cond, LHS, RHS, QuestionLoc);
8535
8536	// First, check the condition.
8537	Cond = UsualUnaryConversions(E: Cond.get());
8538	if (Cond.isInvalid())
8539	return QualType();
8540	if (checkCondition(S&: *this, Cond: Cond.get(), QuestionLoc))
8541	return QualType();
8542
8543	// Handle vectors.
8544	if (LHS.get()->getType()->isVectorType() ||
8545	RHS.get()->getType()->isVectorType())
8546	return CheckVectorOperands(LHS, RHS, Loc: QuestionLoc, /*isCompAssign*/ IsCompAssign: false,
8547	/*AllowBothBool*/ true,
8548	/*AllowBoolConversions*/ AllowBoolConversion: false,
8549	/*AllowBooleanOperation*/ AllowBoolOperation: false,
8550	/*ReportInvalid*/ true);
8551
8552	QualType ResTy = UsualArithmeticConversions(LHS, RHS, Loc: QuestionLoc,
8553	ACK: ArithConvKind::Conditional);
8554	if (LHS.isInvalid() || RHS.isInvalid())
8555	return QualType();
8556
8557	// WebAssembly tables are not allowed as conditional LHS or RHS.
8558	QualType LHSTy = LHS.get()->getType();
8559	QualType RHSTy = RHS.get()->getType();
8560	if (LHSTy->isWebAssemblyTableType() || RHSTy->isWebAssemblyTableType()) {
8561	Diag(Loc: QuestionLoc, DiagID: diag::err_wasm_table_conditional_expression)
8562	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
8563	return QualType();
8564	}
8565
8566	// Diagnose attempts to convert between __ibm128, __float128 and long double
8567	// where such conversions currently can't be handled.
8568	if (unsupportedTypeConversion(S: *this, LHSType: LHSTy, RHSType: RHSTy)) {
8569	Diag(Loc: QuestionLoc,
8570	DiagID: diag::err_typecheck_cond_incompatible_operands) << LHSTy << RHSTy
8571	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
8572	return QualType();
8573	}
8574
8575	// OpenCL v2.0 s6.12.5 - Blocks cannot be used as expressions of the ternary
8576	// selection operator (?:).
8577	if (getLangOpts().OpenCL &&
8578	((int)checkBlockType(S&: *this, E: LHS.get()) | (int)checkBlockType(S&: *this, E: RHS.get()))) {
8579	return QualType();
8580	}
8581
8582	// If both operands have arithmetic type, do the usual arithmetic conversions
8583	// to find a common type: C99 6.5.15p3,5.
8584	if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) {
8585	// Disallow invalid arithmetic conversions, such as those between bit-
8586	// precise integers types of different sizes, or between a bit-precise
8587	// integer and another type.
8588	if (ResTy.isNull() && (LHSTy->isBitIntType() || RHSTy->isBitIntType())) {
8589	Diag(Loc: QuestionLoc, DiagID: diag::err_typecheck_cond_incompatible_operands)
8590	<< LHSTy << RHSTy << LHS.get()->getSourceRange()
8591	<< RHS.get()->getSourceRange();
8592	return QualType();
8593	}
8594
8595	LHS = ImpCastExprToType(E: LHS.get(), Type: ResTy, CK: PrepareScalarCast(Src&: LHS, DestTy: ResTy));
8596	RHS = ImpCastExprToType(E: RHS.get(), Type: ResTy, CK: PrepareScalarCast(Src&: RHS, DestTy: ResTy));
8597
8598	return ResTy;
8599	}
8600
8601	// If both operands are the same structure or union type, the result is that
8602	// type.
8603	if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3
8604	if (const RecordType *RHSRT = RHSTy->getAs<RecordType>())
8605	if (LHSRT->getDecl() == RHSRT->getDecl())
8606	// "If both the operands have structure or union type, the result has
8607	// that type." This implies that CV qualifiers are dropped.
8608	return Context.getCommonSugaredType(X: LHSTy.getUnqualifiedType(),
8609	Y: RHSTy.getUnqualifiedType());
8610	// FIXME: Type of conditional expression must be complete in C mode.
8611	}
8612
8613	// C99 6.5.15p5: "If both operands have void type, the result has void type."
8614	// The following || allows only one side to be void (a GCC-ism).
8615	if (LHSTy->isVoidType() || RHSTy->isVoidType()) {
8616	QualType ResTy;
8617	if (LHSTy->isVoidType() && RHSTy->isVoidType()) {
8618	ResTy = Context.getCommonSugaredType(X: LHSTy, Y: RHSTy);
8619	} else if (RHSTy->isVoidType()) {
8620	ResTy = RHSTy;
8621	Diag(Loc: RHS.get()->getBeginLoc(), DiagID: diag::ext_typecheck_cond_one_void)
8622	<< RHS.get()->getSourceRange();
8623	} else {
8624	ResTy = LHSTy;
8625	Diag(Loc: LHS.get()->getBeginLoc(), DiagID: diag::ext_typecheck_cond_one_void)
8626	<< LHS.get()->getSourceRange();
8627	}
8628	LHS = ImpCastExprToType(E: LHS.get(), Type: ResTy, CK: CK_ToVoid);
8629	RHS = ImpCastExprToType(E: RHS.get(), Type: ResTy, CK: CK_ToVoid);
8630	return ResTy;
8631	}
8632
8633	// C23 6.5.15p7:
8634	// ... if both the second and third operands have nullptr_t type, the
8635	// result also has that type.
8636	if (LHSTy->isNullPtrType() && Context.hasSameType(T1: LHSTy, T2: RHSTy))
8637	return ResTy;
8638
8639	// C99 6.5.15p6 - "if one operand is a null pointer constant, the result has
8640	// the type of the other operand."
8641	if (!checkConditionalNullPointer(S&: *this, NullExpr&: RHS, PointerTy: LHSTy)) return LHSTy;
8642	if (!checkConditionalNullPointer(S&: *this, NullExpr&: LHS, PointerTy: RHSTy)) return RHSTy;
8643
8644	// All objective-c pointer type analysis is done here.
8645	QualType compositeType =
8646	ObjC().FindCompositeObjCPointerType(LHS, RHS, QuestionLoc);
8647	if (LHS.isInvalid() || RHS.isInvalid())
8648	return QualType();
8649	if (!compositeType.isNull())
8650	return compositeType;
8651
8652
8653	// Handle block pointer types.
8654	if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType())
8655	return checkConditionalBlockPointerCompatibility(S&: *this, LHS, RHS,
8656	Loc: QuestionLoc);
8657
8658	// Check constraints for C object pointers types (C99 6.5.15p3,6).
8659	if (LHSTy->isPointerType() && RHSTy->isPointerType())
8660	return checkConditionalObjectPointersCompatibility(S&: *this, LHS, RHS,
8661	Loc: QuestionLoc);
8662
8663	// GCC compatibility: soften pointer/integer mismatch. Note that
8664	// null pointers have been filtered out by this point.
8665	if (checkPointerIntegerMismatch(S&: *this, Int&: LHS, PointerExpr: RHS.get(), Loc: QuestionLoc,
8666	/*IsIntFirstExpr=*/true))
8667	return RHSTy;
8668	if (checkPointerIntegerMismatch(S&: *this, Int&: RHS, PointerExpr: LHS.get(), Loc: QuestionLoc,
8669	/*IsIntFirstExpr=*/false))
8670	return LHSTy;
8671
8672	// Emit a better diagnostic if one of the expressions is a null pointer
8673	// constant and the other is not a pointer type. In this case, the user most
8674	// likely forgot to take the address of the other expression.
8675	if (DiagnoseConditionalForNull(LHSExpr: LHS.get(), RHSExpr: RHS.get(), QuestionLoc))
8676	return QualType();
8677
8678	// Finally, if the LHS and RHS types are canonically the same type, we can
8679	// use the common sugared type.
8680	if (Context.hasSameType(T1: LHSTy, T2: RHSTy))
8681	return Context.getCommonSugaredType(X: LHSTy, Y: RHSTy);
8682
8683	// Otherwise, the operands are not compatible.
8684	Diag(Loc: QuestionLoc, DiagID: diag::err_typecheck_cond_incompatible_operands)
8685	<< LHSTy << RHSTy << LHS.get()->getSourceRange()
8686	<< RHS.get()->getSourceRange();
8687	return QualType();
8688	}
8689
8690	/// SuggestParentheses - Emit a note with a fixit hint that wraps
8691	/// ParenRange in parentheses.
8692	static void SuggestParentheses(Sema &Self, SourceLocation Loc,
8693	const PartialDiagnostic &Note,
8694	SourceRange ParenRange) {
8695	SourceLocation EndLoc = Self.getLocForEndOfToken(Loc: ParenRange.getEnd());
8696	if (ParenRange.getBegin().isFileID() && ParenRange.getEnd().isFileID() &&
8697	EndLoc.isValid()) {
8698	Self.Diag(Loc, PD: Note)
8699	<< FixItHint::CreateInsertion(InsertionLoc: ParenRange.getBegin(), Code: "(")
8700	<< FixItHint::CreateInsertion(InsertionLoc: EndLoc, Code: ")");
8701	} else {
8702	// We can't display the parentheses, so just show the bare note.
8703	Self.Diag(Loc, PD: Note) << ParenRange;
8704	}
8705	}
8706
8707	static bool IsArithmeticOp(BinaryOperatorKind Opc) {
8708	return BinaryOperator::isAdditiveOp(Opc) ||
8709	BinaryOperator::isMultiplicativeOp(Opc) ||
8710	BinaryOperator::isShiftOp(Opc) || Opc == BO_And || Opc == BO_Or;
8711	// This only checks for bitwise-or and bitwise-and, but not bitwise-xor and
8712	// not any of the logical operators. Bitwise-xor is commonly used as a
8713	// logical-xor because there is no logical-xor operator. The logical
8714	// operators, including uses of xor, have a high false positive rate for
8715	// precedence warnings.
8716	}
8717
8718	/// IsArithmeticBinaryExpr - Returns true if E is an arithmetic binary
8719	/// expression, either using a built-in or overloaded operator,
8720	/// and sets *OpCode to the opcode and *RHSExprs to the right-hand side
8721	/// expression.
8722	static bool IsArithmeticBinaryExpr(const Expr *E, BinaryOperatorKind *Opcode,
8723	const Expr **RHSExprs) {
8724	// Don't strip parenthesis: we should not warn if E is in parenthesis.
8725	E = E->IgnoreImpCasts();
8726	E = E->IgnoreConversionOperatorSingleStep();
8727	E = E->IgnoreImpCasts();
8728	if (const auto *MTE = dyn_cast<MaterializeTemporaryExpr>(Val: E)) {
8729	E = MTE->getSubExpr();
8730	E = E->IgnoreImpCasts();
8731	}
8732
8733	// Built-in binary operator.
8734	if (const auto *OP = dyn_cast<BinaryOperator>(Val: E);
8735	OP && IsArithmeticOp(Opc: OP->getOpcode())) {
8736	*Opcode = OP->getOpcode();
8737	*RHSExprs = OP->getRHS();
8738	return true;
8739	}
8740
8741	// Overloaded operator.
8742	if (const auto *Call = dyn_cast<CXXOperatorCallExpr>(Val: E)) {
8743	if (Call->getNumArgs() != 2)
8744	return false;
8745
8746	// Make sure this is really a binary operator that is safe to pass into
8747	// BinaryOperator::getOverloadedOpcode(), e.g. it's not a subscript op.
8748	OverloadedOperatorKind OO = Call->getOperator();
8749	if (OO < OO_Plus || OO > OO_Arrow ||
8750	OO == OO_PlusPlus || OO == OO_MinusMinus)
8751	return false;
8752
8753	BinaryOperatorKind OpKind = BinaryOperator::getOverloadedOpcode(OO);
8754	if (IsArithmeticOp(Opc: OpKind)) {
8755	*Opcode = OpKind;
8756	*RHSExprs = Call->getArg(Arg: 1);
8757	return true;
8758	}
8759	}
8760
8761	return false;
8762	}
8763
8764	/// ExprLooksBoolean - Returns true if E looks boolean, i.e. it has boolean type
8765	/// or is a logical expression such as (x==y) which has int type, but is
8766	/// commonly interpreted as boolean.
8767	static bool ExprLooksBoolean(const Expr *E) {
8768	E = E->IgnoreParenImpCasts();
8769
8770	if (E->getType()->isBooleanType())
8771	return true;
8772	if (const auto *OP = dyn_cast<BinaryOperator>(Val: E))
8773	return OP->isComparisonOp() || OP->isLogicalOp();
8774	if (const auto *OP = dyn_cast<UnaryOperator>(Val: E))
8775	return OP->getOpcode() == UO_LNot;
8776	if (E->getType()->isPointerType())
8777	return true;
8778	// FIXME: What about overloaded operator calls returning "unspecified boolean
8779	// type"s (commonly pointer-to-members)?
8780
8781	return false;
8782	}
8783
8784	/// DiagnoseConditionalPrecedence - Emit a warning when a conditional operator
8785	/// and binary operator are mixed in a way that suggests the programmer assumed
8786	/// the conditional operator has higher precedence, for example:
8787	/// "int x = a + someBinaryCondition ? 1 : 2".
8788	static void DiagnoseConditionalPrecedence(Sema &Self, SourceLocation OpLoc,
8789	Expr *Condition, const Expr *LHSExpr,
8790	const Expr *RHSExpr) {
8791	BinaryOperatorKind CondOpcode;
8792	const Expr *CondRHS;
8793
8794	if (!IsArithmeticBinaryExpr(E: Condition, Opcode: &CondOpcode, RHSExprs: &CondRHS))
8795	return;
8796	if (!ExprLooksBoolean(E: CondRHS))
8797	return;
8798
8799	// The condition is an arithmetic binary expression, with a right-
8800	// hand side that looks boolean, so warn.
8801
8802	unsigned DiagID = BinaryOperator::isBitwiseOp(Opc: CondOpcode)
8803	? diag::warn_precedence_bitwise_conditional
8804	: diag::warn_precedence_conditional;
8805
8806	Self.Diag(Loc: OpLoc, DiagID)
8807	<< Condition->getSourceRange()
8808	<< BinaryOperator::getOpcodeStr(Op: CondOpcode);
8809
8810	SuggestParentheses(
8811	Self, Loc: OpLoc,
8812	Note: Self.PDiag(DiagID: diag::note_precedence_silence)
8813	<< BinaryOperator::getOpcodeStr(Op: CondOpcode),
8814	ParenRange: SourceRange(Condition->getBeginLoc(), Condition->getEndLoc()));
8815
8816	SuggestParentheses(Self, Loc: OpLoc,
8817	Note: Self.PDiag(DiagID: diag::note_precedence_conditional_first),
8818	ParenRange: SourceRange(CondRHS->getBeginLoc(), RHSExpr->getEndLoc()));
8819	}
8820
8821	/// Compute the nullability of a conditional expression.
8822	static QualType computeConditionalNullability(QualType ResTy, bool IsBin,
8823	QualType LHSTy, QualType RHSTy,
8824	ASTContext &Ctx) {
8825	if (!ResTy->isAnyPointerType())
8826	return ResTy;
8827
8828	auto GetNullability = [](QualType Ty) {
8829	std::optional<NullabilityKind> Kind = Ty->getNullability();
8830	if (Kind) {
8831	// For our purposes, treat _Nullable_result as _Nullable.
8832	if (*Kind == NullabilityKind::NullableResult)
8833	return NullabilityKind::Nullable;
8834	return *Kind;
8835	}
8836	return NullabilityKind::Unspecified;
8837	};
8838
8839	auto LHSKind = GetNullability(LHSTy), RHSKind = GetNullability(RHSTy);
8840	NullabilityKind MergedKind;
8841
8842	// Compute nullability of a binary conditional expression.
8843	if (IsBin) {
8844	if (LHSKind == NullabilityKind::NonNull)
8845	MergedKind = NullabilityKind::NonNull;
8846	else
8847	MergedKind = RHSKind;
8848	// Compute nullability of a normal conditional expression.
8849	} else {
8850	if (LHSKind == NullabilityKind::Nullable ||
8851	RHSKind == NullabilityKind::Nullable)
8852	MergedKind = NullabilityKind::Nullable;
8853	else if (LHSKind == NullabilityKind::NonNull)
8854	MergedKind = RHSKind;
8855	else if (RHSKind == NullabilityKind::NonNull)
8856	MergedKind = LHSKind;
8857	else
8858	MergedKind = NullabilityKind::Unspecified;
8859	}
8860
8861	// Return if ResTy already has the correct nullability.
8862	if (GetNullability(ResTy) == MergedKind)
8863	return ResTy;
8864
8865	// Strip all nullability from ResTy.
8866	while (ResTy->getNullability())
8867	ResTy = ResTy.getSingleStepDesugaredType(Context: Ctx);
8868
8869	// Create a new AttributedType with the new nullability kind.
8870	return Ctx.getAttributedType(nullability: MergedKind, modifiedType: ResTy, equivalentType: ResTy);
8871	}
8872
8873	ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc,
8874	SourceLocation ColonLoc,
8875	Expr *CondExpr, Expr *LHSExpr,
8876	Expr *RHSExpr) {
8877	// If this is the gnu "x ?: y" extension, analyze the types as though the LHS
8878	// was the condition.
8879	OpaqueValueExpr *opaqueValue = nullptr;
8880	Expr *commonExpr = nullptr;
8881	if (!LHSExpr) {
8882	commonExpr = CondExpr;
8883	// Lower out placeholder types first. This is important so that we don't
8884	// try to capture a placeholder. This happens in few cases in C++; such
8885	// as Objective-C++'s dictionary subscripting syntax.
8886	if (commonExpr->hasPlaceholderType()) {
8887	ExprResult result = CheckPlaceholderExpr(E: commonExpr);
8888	if (!result.isUsable()) return ExprError();
8889	commonExpr = result.get();
8890	}
8891	// We usually want to apply unary conversions *before* saving, except
8892	// in the special case of a C++ l-value conditional.
8893	if (!(getLangOpts().CPlusPlus
8894	&& !commonExpr->isTypeDependent()
8895	&& commonExpr->getValueKind() == RHSExpr->getValueKind()
8896	&& commonExpr->isGLValue()
8897	&& commonExpr->isOrdinaryOrBitFieldObject()
8898	&& RHSExpr->isOrdinaryOrBitFieldObject()
8899	&& Context.hasSameType(T1: commonExpr->getType(), T2: RHSExpr->getType()))) {
8900	ExprResult commonRes = UsualUnaryConversions(E: commonExpr);
8901	if (commonRes.isInvalid())
8902	return ExprError();
8903	commonExpr = commonRes.get();
8904	}
8905
8906	// If the common expression is a class or array prvalue, materialize it
8907	// so that we can safely refer to it multiple times.
8908	if (commonExpr->isPRValue() && (commonExpr->getType()->isRecordType() ||
8909	commonExpr->getType()->isArrayType())) {
8910	ExprResult MatExpr = TemporaryMaterializationConversion(E: commonExpr);
8911	if (MatExpr.isInvalid())
8912	return ExprError();
8913	commonExpr = MatExpr.get();
8914	}
8915
8916	opaqueValue = new (Context) OpaqueValueExpr(commonExpr->getExprLoc(),
8917	commonExpr->getType(),
8918	commonExpr->getValueKind(),
8919	commonExpr->getObjectKind(),
8920	commonExpr);
8921	LHSExpr = CondExpr = opaqueValue;
8922	}
8923
8924	QualType LHSTy = LHSExpr->getType(), RHSTy = RHSExpr->getType();
8925	ExprValueKind VK = VK_PRValue;
8926	ExprObjectKind OK = OK_Ordinary;
8927	ExprResult Cond = CondExpr, LHS = LHSExpr, RHS = RHSExpr;
8928	QualType result = CheckConditionalOperands(Cond, LHS, RHS,
8929	VK, OK, QuestionLoc);
8930	if (result.isNull() || Cond.isInvalid() || LHS.isInvalid() ||
8931	RHS.isInvalid())
8932	return ExprError();
8933
8934	DiagnoseConditionalPrecedence(Self&: *this, OpLoc: QuestionLoc, Condition: Cond.get(), LHSExpr: LHS.get(),
8935	RHSExpr: RHS.get());
8936
8937	CheckBoolLikeConversion(E: Cond.get(), CC: QuestionLoc);
8938
8939	result = computeConditionalNullability(ResTy: result, IsBin: commonExpr, LHSTy, RHSTy,
8940	Ctx&: Context);
8941
8942	if (!commonExpr)
8943	return new (Context)
8944	ConditionalOperator(Cond.get(), QuestionLoc, LHS.get(), ColonLoc,
8945	RHS.get(), result, VK, OK);
8946
8947	return new (Context) BinaryConditionalOperator(
8948	commonExpr, opaqueValue, Cond.get(), LHS.get(), RHS.get(), QuestionLoc,
8949	ColonLoc, result, VK, OK);
8950	}
8951
8952	bool Sema::IsInvalidSMECallConversion(QualType FromType, QualType ToType) {
8953	unsigned FromAttributes = 0, ToAttributes = 0;
8954	if (const auto *FromFn =
8955	dyn_cast<FunctionProtoType>(Val: Context.getCanonicalType(T: FromType)))
8956	FromAttributes =
8957	FromFn->getAArch64SMEAttributes() & FunctionType::SME_AttributeMask;
8958	if (const auto *ToFn =
8959	dyn_cast<FunctionProtoType>(Val: Context.getCanonicalType(T: ToType)))
8960	ToAttributes =
8961	ToFn->getAArch64SMEAttributes() & FunctionType::SME_AttributeMask;
8962
8963	return FromAttributes != ToAttributes;
8964	}
8965
8966	// Check if we have a conversion between incompatible cmse function pointer
8967	// types, that is, a conversion between a function pointer with the
8968	// cmse_nonsecure_call attribute and one without.
8969	static bool IsInvalidCmseNSCallConversion(Sema &S, QualType FromType,
8970	QualType ToType) {
8971	if (const auto *ToFn =
8972	dyn_cast<FunctionType>(Val: S.Context.getCanonicalType(T: ToType))) {
8973	if (const auto *FromFn =
8974	dyn_cast<FunctionType>(Val: S.Context.getCanonicalType(T: FromType))) {
8975	FunctionType::ExtInfo ToEInfo = ToFn->getExtInfo();
8976	FunctionType::ExtInfo FromEInfo = FromFn->getExtInfo();
8977
8978	return ToEInfo.getCmseNSCall() != FromEInfo.getCmseNSCall();
8979	}
8980	}
8981	return false;
8982	}
8983
8984	// checkPointerTypesForAssignment - This is a very tricky routine (despite
8985	// being closely modeled after the C99 spec:-). The odd characteristic of this
8986	// routine is it effectively iqnores the qualifiers on the top level pointee.
8987	// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3].
8988	// FIXME: add a couple examples in this comment.
8989	static AssignConvertType checkPointerTypesForAssignment(Sema &S,
8990	QualType LHSType,
8991	QualType RHSType,
8992	SourceLocation Loc) {
8993	assert(LHSType.isCanonical() && "LHS not canonicalized!");
8994	assert(RHSType.isCanonical() && "RHS not canonicalized!");
8995
8996	// get the "pointed to" type (ignoring qualifiers at the top level)
8997	const Type *lhptee, *rhptee;
8998	Qualifiers lhq, rhq;
8999	std::tie(args&: lhptee, args&: lhq) =
9000	cast<PointerType>(Val&: LHSType)->getPointeeType().split().asPair();
9001	std::tie(args&: rhptee, args&: rhq) =
9002	cast<PointerType>(Val&: RHSType)->getPointeeType().split().asPair();
9003
9004	AssignConvertType ConvTy = AssignConvertType::Compatible;
9005
9006	// C99 6.5.16.1p1: This following citation is common to constraints
9007	// 3 & 4 (below). ...and the type *pointed to* by the left has all the
9008	// qualifiers of the type *pointed to* by the right;
9009
9010	// As a special case, 'non-__weak A *' -> 'non-__weak const *' is okay.
9011	if (lhq.getObjCLifetime() != rhq.getObjCLifetime() &&
9012	lhq.compatiblyIncludesObjCLifetime(other: rhq)) {
9013	// Ignore lifetime for further calculation.
9014	lhq.removeObjCLifetime();
9015	rhq.removeObjCLifetime();
9016	}
9017
9018	if (!lhq.compatiblyIncludes(other: rhq, Ctx: S.getASTContext())) {
9019	// Treat address-space mismatches as fatal.
9020	if (!lhq.isAddressSpaceSupersetOf(other: rhq, Ctx: S.getASTContext()))
9021	return AssignConvertType::IncompatiblePointerDiscardsQualifiers;
9022
9023	// It's okay to add or remove GC or lifetime qualifiers when converting to
9024	// and from void*.
9025	else if (lhq.withoutObjCGCAttr().withoutObjCLifetime().compatiblyIncludes(
9026	other: rhq.withoutObjCGCAttr().withoutObjCLifetime(),
9027	Ctx: S.getASTContext()) &&
9028	(lhptee->isVoidType() || rhptee->isVoidType()))
9029	; // keep old
9030
9031	// Treat lifetime mismatches as fatal.
9032	else if (lhq.getObjCLifetime() != rhq.getObjCLifetime())
9033	ConvTy = AssignConvertType::IncompatiblePointerDiscardsQualifiers;
9034
9035	// Treat pointer-auth mismatches as fatal.
9036	else if (!lhq.getPointerAuth().isEquivalent(Other: rhq.getPointerAuth()))
9037	ConvTy = AssignConvertType::IncompatiblePointerDiscardsQualifiers;
9038
9039	// For GCC/MS compatibility, other qualifier mismatches are treated
9040	// as still compatible in C.
9041	else
9042	ConvTy = AssignConvertType::CompatiblePointerDiscardsQualifiers;
9043	}
9044
9045	// C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or
9046	// incomplete type and the other is a pointer to a qualified or unqualified
9047	// version of void...
9048	if (lhptee->isVoidType()) {
9049	if (rhptee->isIncompleteOrObjectType())
9050	return ConvTy;
9051
9052	// As an extension, we allow cast to/from void* to function pointer.
9053	assert(rhptee->isFunctionType());
9054	return AssignConvertType::FunctionVoidPointer;
9055	}
9056
9057	if (rhptee->isVoidType()) {
9058	// In C, void * to another pointer type is compatible, but we want to note
9059	// that there will be an implicit conversion happening here.
9060	if (lhptee->isIncompleteOrObjectType())
9061	return ConvTy == AssignConvertType::Compatible &&
9062	!S.getLangOpts().CPlusPlus
9063	? AssignConvertType::CompatibleVoidPtrToNonVoidPtr
9064	: ConvTy;
9065
9066	// As an extension, we allow cast to/from void* to function pointer.
9067	assert(lhptee->isFunctionType());
9068	return AssignConvertType::FunctionVoidPointer;
9069	}
9070
9071	if (!S.Diags.isIgnored(
9072	DiagID: diag::warn_typecheck_convert_incompatible_function_pointer_strict,
9073	Loc) &&
9074	RHSType->isFunctionPointerType() && LHSType->isFunctionPointerType() &&
9075	!S.TryFunctionConversion(FromType: RHSType, ToType: LHSType, ResultTy&: RHSType))
9076	return AssignConvertType::IncompatibleFunctionPointerStrict;
9077
9078	// C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or
9079	// unqualified versions of compatible types, ...
9080	QualType ltrans = QualType(lhptee, 0), rtrans = QualType(rhptee, 0);
9081	if (!S.Context.typesAreCompatible(T1: ltrans, T2: rtrans)) {
9082	// Check if the pointee types are compatible ignoring the sign.
9083	// We explicitly check for char so that we catch "char" vs
9084	// "unsigned char" on systems where "char" is unsigned.
9085	if (lhptee->isCharType())
9086	ltrans = S.Context.UnsignedCharTy;
9087	else if (lhptee->hasSignedIntegerRepresentation())
9088	ltrans = S.Context.getCorrespondingUnsignedType(T: ltrans);
9089
9090	if (rhptee->isCharType())
9091	rtrans = S.Context.UnsignedCharTy;
9092	else if (rhptee->hasSignedIntegerRepresentation())
9093	rtrans = S.Context.getCorrespondingUnsignedType(T: rtrans);
9094
9095	if (ltrans == rtrans) {
9096	// Types are compatible ignoring the sign. Qualifier incompatibility
9097	// takes priority over sign incompatibility because the sign
9098	// warning can be disabled.
9099	if (!S.IsAssignConvertCompatible(ConvTy))
9100	return ConvTy;
9101
9102	return AssignConvertType::IncompatiblePointerSign;
9103	}
9104
9105	// If we are a multi-level pointer, it's possible that our issue is simply
9106	// one of qualification - e.g. char ** -> const char ** is not allowed. If
9107	// the eventual target type is the same and the pointers have the same
9108	// level of indirection, this must be the issue.
9109	if (isa<PointerType>(Val: lhptee) && isa<PointerType>(Val: rhptee)) {
9110	do {
9111	std::tie(args&: lhptee, args&: lhq) =
9112	cast<PointerType>(Val: lhptee)->getPointeeType().split().asPair();
9113	std::tie(args&: rhptee, args&: rhq) =
9114	cast<PointerType>(Val: rhptee)->getPointeeType().split().asPair();
9115
9116	// Inconsistent address spaces at this point is invalid, even if the
9117	// address spaces would be compatible.
9118	// FIXME: This doesn't catch address space mismatches for pointers of
9119	// different nesting levels, like:
9120	// __local int *** a;
9121	// int ** b = a;
9122	// It's not clear how to actually determine when such pointers are
9123	// invalidly incompatible.
9124	if (lhq.getAddressSpace() != rhq.getAddressSpace())
9125	return AssignConvertType::
9126	IncompatibleNestedPointerAddressSpaceMismatch;
9127
9128	} while (isa<PointerType>(Val: lhptee) && isa<PointerType>(Val: rhptee));
9129
9130	if (lhptee == rhptee)
9131	return AssignConvertType::IncompatibleNestedPointerQualifiers;
9132	}
9133
9134	// General pointer incompatibility takes priority over qualifiers.
9135	if (RHSType->isFunctionPointerType() && LHSType->isFunctionPointerType())
9136	return AssignConvertType::IncompatibleFunctionPointer;
9137	return AssignConvertType::IncompatiblePointer;
9138	}
9139	bool DiscardingCFIUncheckedCallee, AddingCFIUncheckedCallee;
9140	if (!S.getLangOpts().CPlusPlus &&
9141	S.IsFunctionConversion(FromType: ltrans, ToType: rtrans, DiscardingCFIUncheckedCallee: &DiscardingCFIUncheckedCallee,
9142	AddingCFIUncheckedCallee: &AddingCFIUncheckedCallee)) {
9143	// Allow conversions between CFIUncheckedCallee-ness.
9144	if (!DiscardingCFIUncheckedCallee && !AddingCFIUncheckedCallee)
9145	return AssignConvertType::IncompatibleFunctionPointer;
9146	}
9147	if (IsInvalidCmseNSCallConversion(S, FromType: ltrans, ToType: rtrans))
9148	return AssignConvertType::IncompatibleFunctionPointer;
9149	if (S.IsInvalidSMECallConversion(FromType: rtrans, ToType: ltrans))
9150	return AssignConvertType::IncompatibleFunctionPointer;
9151	return ConvTy;
9152	}
9153
9154	/// checkBlockPointerTypesForAssignment - This routine determines whether two
9155	/// block pointer types are compatible or whether a block and normal pointer
9156	/// are compatible. It is more restrict than comparing two function pointer
9157	// types.
9158	static AssignConvertType checkBlockPointerTypesForAssignment(Sema &S,
9159	QualType LHSType,
9160	QualType RHSType) {
9161	assert(LHSType.isCanonical() && "LHS not canonicalized!");
9162	assert(RHSType.isCanonical() && "RHS not canonicalized!");
9163
9164	QualType lhptee, rhptee;
9165
9166	// get the "pointed to" type (ignoring qualifiers at the top level)
9167	lhptee = cast<BlockPointerType>(Val&: LHSType)->getPointeeType();
9168	rhptee = cast<BlockPointerType>(Val&: RHSType)->getPointeeType();
9169
9170	// In C++, the types have to match exactly.
9171	if (S.getLangOpts().CPlusPlus)
9172	return AssignConvertType::IncompatibleBlockPointer;
9173
9174	AssignConvertType ConvTy = AssignConvertType::Compatible;
9175
9176	// For blocks we enforce that qualifiers are identical.
9177	Qualifiers LQuals = lhptee.getLocalQualifiers();
9178	Qualifiers RQuals = rhptee.getLocalQualifiers();
9179	if (S.getLangOpts().OpenCL) {
9180	LQuals.removeAddressSpace();
9181	RQuals.removeAddressSpace();
9182	}
9183	if (LQuals != RQuals)
9184	ConvTy = AssignConvertType::CompatiblePointerDiscardsQualifiers;
9185
9186	// FIXME: OpenCL doesn't define the exact compile time semantics for a block
9187	// assignment.
9188	// The current behavior is similar to C++ lambdas. A block might be
9189	// assigned to a variable iff its return type and parameters are compatible
9190	// (C99 6.2.7) with the corresponding return type and parameters of the LHS of
9191	// an assignment. Presumably it should behave in way that a function pointer
9192	// assignment does in C, so for each parameter and return type:
9193	// * CVR and address space of LHS should be a superset of CVR and address
9194	// space of RHS.
9195	// * unqualified types should be compatible.
9196	if (S.getLangOpts().OpenCL) {
9197	if (!S.Context.typesAreBlockPointerCompatible(
9198	S.Context.getQualifiedType(T: LHSType.getUnqualifiedType(), Qs: LQuals),
9199	S.Context.getQualifiedType(T: RHSType.getUnqualifiedType(), Qs: RQuals)))
9200	return AssignConvertType::IncompatibleBlockPointer;
9201	} else if (!S.Context.typesAreBlockPointerCompatible(LHSType, RHSType))
9202	return AssignConvertType::IncompatibleBlockPointer;
9203
9204	return ConvTy;
9205	}
9206
9207	/// checkObjCPointerTypesForAssignment - Compares two objective-c pointer types
9208	/// for assignment compatibility.
9209	static AssignConvertType checkObjCPointerTypesForAssignment(Sema &S,
9210	QualType LHSType,
9211	QualType RHSType) {
9212	assert(LHSType.isCanonical() && "LHS was not canonicalized!");
9213	assert(RHSType.isCanonical() && "RHS was not canonicalized!");
9214
9215	if (LHSType->isObjCBuiltinType()) {
9216	// Class is not compatible with ObjC object pointers.
9217	if (LHSType->isObjCClassType() && !RHSType->isObjCBuiltinType() &&
9218	!RHSType->isObjCQualifiedClassType())
9219	return AssignConvertType::IncompatiblePointer;
9220	return AssignConvertType::Compatible;
9221	}
9222	if (RHSType->isObjCBuiltinType()) {
9223	if (RHSType->isObjCClassType() && !LHSType->isObjCBuiltinType() &&
9224	!LHSType->isObjCQualifiedClassType())
9225	return AssignConvertType::IncompatiblePointer;
9226	return AssignConvertType::Compatible;
9227	}
9228	QualType lhptee = LHSType->castAs<ObjCObjectPointerType>()->getPointeeType();
9229	QualType rhptee = RHSType->castAs<ObjCObjectPointerType>()->getPointeeType();
9230
9231	if (!lhptee.isAtLeastAsQualifiedAs(other: rhptee, Ctx: S.getASTContext()) &&
9232	// make an exception for id<P>
9233	!LHSType->isObjCQualifiedIdType())
9234	return AssignConvertType::CompatiblePointerDiscardsQualifiers;
9235
9236	if (S.Context.typesAreCompatible(T1: LHSType, T2: RHSType))
9237	return AssignConvertType::Compatible;
9238	if (LHSType->isObjCQualifiedIdType() || RHSType->isObjCQualifiedIdType())
9239	return AssignConvertType::IncompatibleObjCQualifiedId;
9240	return AssignConvertType::IncompatiblePointer;
9241	}
9242
9243	AssignConvertType Sema::CheckAssignmentConstraints(SourceLocation Loc,
9244	QualType LHSType,
9245	QualType RHSType) {
9246	// Fake up an opaque expression. We don't actually care about what
9247	// cast operations are required, so if CheckAssignmentConstraints
9248	// adds casts to this they'll be wasted, but fortunately that doesn't
9249	// usually happen on valid code.
9250	OpaqueValueExpr RHSExpr(Loc, RHSType, VK_PRValue);
9251	ExprResult RHSPtr = &RHSExpr;
9252	CastKind K;
9253
9254	return CheckAssignmentConstraints(LHSType, RHS&: RHSPtr, Kind&: K, /*ConvertRHS=*/false);
9255	}
9256
9257	/// This helper function returns true if QT is a vector type that has element
9258	/// type ElementType.
9259	static bool isVector(QualType QT, QualType ElementType) {
9260	if (const VectorType *VT = QT->getAs<VectorType>())
9261	return VT->getElementType().getCanonicalType() == ElementType;
9262	return false;
9263	}
9264
9265	/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently
9266	/// has code to accommodate several GCC extensions when type checking
9267	/// pointers. Here are some objectionable examples that GCC considers warnings:
9268	///
9269	/// int a, *pint;
9270	/// short *pshort;
9271	/// struct foo *pfoo;
9272	///
9273	/// pint = pshort; // warning: assignment from incompatible pointer type
9274	/// a = pint; // warning: assignment makes integer from pointer without a cast
9275	/// pint = a; // warning: assignment makes pointer from integer without a cast
9276	/// pint = pfoo; // warning: assignment from incompatible pointer type
9277	///
9278	/// As a result, the code for dealing with pointers is more complex than the
9279	/// C99 spec dictates.
9280	///
9281	/// Sets 'Kind' for any result kind except Incompatible.
9282	AssignConvertType Sema::CheckAssignmentConstraints(QualType LHSType,
9283	ExprResult &RHS,
9284	CastKind &Kind,
9285	bool ConvertRHS) {
9286	QualType RHSType = RHS.get()->getType();
9287	QualType OrigLHSType = LHSType;
9288
9289	// Get canonical types. We're not formatting these types, just comparing
9290	// them.
9291	LHSType = Context.getCanonicalType(T: LHSType).getUnqualifiedType();
9292	RHSType = Context.getCanonicalType(T: RHSType).getUnqualifiedType();
9293
9294	// Common case: no conversion required.
9295	if (LHSType == RHSType) {
9296	Kind = CK_NoOp;
9297	return AssignConvertType::Compatible;
9298	}
9299
9300	// If the LHS has an __auto_type, there are no additional type constraints
9301	// to be worried about.
9302	if (const auto *AT = dyn_cast<AutoType>(Val&: LHSType)) {
9303	if (AT->isGNUAutoType()) {
9304	Kind = CK_NoOp;
9305	return AssignConvertType::Compatible;
9306	}
9307	}
9308
9309	// If we have an atomic type, try a non-atomic assignment, then just add an
9310	// atomic qualification step.
9311	if (const AtomicType *AtomicTy = dyn_cast<AtomicType>(Val&: LHSType)) {
9312	AssignConvertType Result =
9313	CheckAssignmentConstraints(LHSType: AtomicTy->getValueType(), RHS, Kind);
9314	if (!IsAssignConvertCompatible(ConvTy: Result))
9315	return Result;
9316	if (Kind != CK_NoOp && ConvertRHS)
9317	RHS = ImpCastExprToType(E: RHS.get(), Type: AtomicTy->getValueType(), CK: Kind);
9318	Kind = CK_NonAtomicToAtomic;
9319	return Result;
9320	}
9321
9322	// If the left-hand side is a reference type, then we are in a
9323	// (rare!) case where we've allowed the use of references in C,
9324	// e.g., as a parameter type in a built-in function. In this case,
9325	// just make sure that the type referenced is compatible with the
9326	// right-hand side type. The caller is responsible for adjusting
9327	// LHSType so that the resulting expression does not have reference
9328	// type.
9329	if (const ReferenceType *LHSTypeRef = LHSType->getAs<ReferenceType>()) {
9330	if (Context.typesAreCompatible(T1: LHSTypeRef->getPointeeType(), T2: RHSType)) {
9331	Kind = CK_LValueBitCast;
9332	return AssignConvertType::Compatible;
9333	}
9334	return AssignConvertType::Incompatible;
9335	}
9336
9337	// Allow scalar to ExtVector assignments, and assignments of an ExtVector type
9338	// to the same ExtVector type.
9339	if (LHSType->isExtVectorType()) {
9340	if (RHSType->isExtVectorType())
9341	return AssignConvertType::Incompatible;
9342	if (RHSType->isArithmeticType()) {
9343	// CK_VectorSplat does T -> vector T, so first cast to the element type.
9344	if (ConvertRHS)
9345	RHS = prepareVectorSplat(VectorTy: LHSType, SplattedExpr: RHS.get());
9346	Kind = CK_VectorSplat;
9347	return AssignConvertType::Compatible;
9348	}
9349	}
9350
9351	// Conversions to or from vector type.
9352	if (LHSType->isVectorType() || RHSType->isVectorType()) {
9353	if (LHSType->isVectorType() && RHSType->isVectorType()) {
9354	// Allow assignments of an AltiVec vector type to an equivalent GCC
9355	// vector type and vice versa
9356	if (Context.areCompatibleVectorTypes(FirstVec: LHSType, SecondVec: RHSType)) {
9357	Kind = CK_BitCast;
9358	return AssignConvertType::Compatible;
9359	}
9360
9361	// If we are allowing lax vector conversions, and LHS and RHS are both
9362	// vectors, the total size only needs to be the same. This is a bitcast;
9363	// no bits are changed but the result type is different.
9364	if (isLaxVectorConversion(srcTy: RHSType, destTy: LHSType)) {
9365	// The default for lax vector conversions with Altivec vectors will
9366	// change, so if we are converting between vector types where
9367	// at least one is an Altivec vector, emit a warning.
9368	if (Context.getTargetInfo().getTriple().isPPC() &&
9369	anyAltivecTypes(SrcTy: RHSType, DestTy: LHSType) &&
9370	!Context.areCompatibleVectorTypes(FirstVec: RHSType, SecondVec: LHSType))
9371	Diag(Loc: RHS.get()->getExprLoc(), DiagID: diag::warn_deprecated_lax_vec_conv_all)
9372	<< RHSType << LHSType;
9373	Kind = CK_BitCast;
9374	return AssignConvertType::IncompatibleVectors;
9375	}
9376	}
9377
9378	// When the RHS comes from another lax conversion (e.g. binops between
9379	// scalars and vectors) the result is canonicalized as a vector. When the
9380	// LHS is also a vector, the lax is allowed by the condition above. Handle
9381	// the case where LHS is a scalar.
9382	if (LHSType->isScalarType()) {
9383	const VectorType *VecType = RHSType->getAs<VectorType>();
9384	if (VecType && VecType->getNumElements() == 1 &&
9385	isLaxVectorConversion(srcTy: RHSType, destTy: LHSType)) {
9386	if (Context.getTargetInfo().getTriple().isPPC() &&
9387	(VecType->getVectorKind() == VectorKind::AltiVecVector ||
9388	VecType->getVectorKind() == VectorKind::AltiVecBool ||
9389	VecType->getVectorKind() == VectorKind::AltiVecPixel))
9390	Diag(Loc: RHS.get()->getExprLoc(), DiagID: diag::warn_deprecated_lax_vec_conv_all)
9391	<< RHSType << LHSType;
9392	ExprResult *VecExpr = &RHS;
9393	*VecExpr = ImpCastExprToType(E: VecExpr->get(), Type: LHSType, CK: CK_BitCast);
9394	Kind = CK_BitCast;
9395	return AssignConvertType::Compatible;
9396	}
9397	}
9398
9399	// Allow assignments between fixed-length and sizeless SVE vectors.
9400	if ((LHSType->isSVESizelessBuiltinType() && RHSType->isVectorType()) ||
9401	(LHSType->isVectorType() && RHSType->isSVESizelessBuiltinType()))
9402	if (ARM().areCompatibleSveTypes(FirstType: LHSType, SecondType: RHSType) ||
9403	ARM().areLaxCompatibleSveTypes(FirstType: LHSType, SecondType: RHSType)) {
9404	Kind = CK_BitCast;
9405	return AssignConvertType::Compatible;
9406	}
9407
9408	// Allow assignments between fixed-length and sizeless RVV vectors.
9409	if ((LHSType->isRVVSizelessBuiltinType() && RHSType->isVectorType()) ||
9410	(LHSType->isVectorType() && RHSType->isRVVSizelessBuiltinType())) {
9411	if (Context.areCompatibleRVVTypes(FirstType: LHSType, SecondType: RHSType) ||
9412	Context.areLaxCompatibleRVVTypes(FirstType: LHSType, SecondType: RHSType)) {
9413	Kind = CK_BitCast;
9414	return AssignConvertType::Compatible;
9415	}
9416	}
9417
9418	return AssignConvertType::Incompatible;
9419	}
9420
9421	// Diagnose attempts to convert between __ibm128, __float128 and long double
9422	// where such conversions currently can't be handled.
9423	if (unsupportedTypeConversion(S: *this, LHSType, RHSType))
9424	return AssignConvertType::Incompatible;
9425
9426	// Disallow assigning a _Complex to a real type in C++ mode since it simply
9427	// discards the imaginary part.
9428	if (getLangOpts().CPlusPlus && RHSType->getAs<ComplexType>() &&
9429	!LHSType->getAs<ComplexType>())
9430	return AssignConvertType::Incompatible;
9431
9432	// Arithmetic conversions.
9433	if (LHSType->isArithmeticType() && RHSType->isArithmeticType() &&
9434	!(getLangOpts().CPlusPlus && LHSType->isEnumeralType())) {
9435	if (ConvertRHS)
9436	Kind = PrepareScalarCast(Src&: RHS, DestTy: LHSType);
9437	return AssignConvertType::Compatible;
9438	}
9439
9440	// Conversions to normal pointers.
9441	if (const PointerType *LHSPointer = dyn_cast<PointerType>(Val&: LHSType)) {
9442	// U* -> T*
9443	if (isa<PointerType>(Val: RHSType)) {
9444	LangAS AddrSpaceL = LHSPointer->getPointeeType().getAddressSpace();
9445	LangAS AddrSpaceR = RHSType->getPointeeType().getAddressSpace();
9446	if (AddrSpaceL != AddrSpaceR)
9447	Kind = CK_AddressSpaceConversion;
9448	else if (Context.hasCvrSimilarType(T1: RHSType, T2: LHSType))
9449	Kind = CK_NoOp;
9450	else
9451	Kind = CK_BitCast;
9452	return checkPointerTypesForAssignment(S&: *this, LHSType, RHSType,
9453	Loc: RHS.get()->getBeginLoc());
9454	}
9455
9456	// int -> T*
9457	if (RHSType->isIntegerType()) {
9458	Kind = CK_IntegralToPointer; // FIXME: null?
9459	return AssignConvertType::IntToPointer;
9460	}
9461
9462	// C pointers are not compatible with ObjC object pointers,
9463	// with two exceptions:
9464	if (isa<ObjCObjectPointerType>(Val: RHSType)) {
9465	// - conversions to void*
9466	if (LHSPointer->getPointeeType()->isVoidType()) {
9467	Kind = CK_BitCast;
9468	return AssignConvertType::Compatible;
9469	}
9470
9471	// - conversions from 'Class' to the redefinition type
9472	if (RHSType->isObjCClassType() &&
9473	Context.hasSameType(T1: LHSType,
9474	T2: Context.getObjCClassRedefinitionType())) {
9475	Kind = CK_BitCast;
9476	return AssignConvertType::Compatible;
9477	}
9478
9479	Kind = CK_BitCast;
9480	return AssignConvertType::IncompatiblePointer;
9481	}
9482
9483	// U^ -> void*
9484	if (RHSType->getAs<BlockPointerType>()) {
9485	if (LHSPointer->getPointeeType()->isVoidType()) {
9486	LangAS AddrSpaceL = LHSPointer->getPointeeType().getAddressSpace();
9487	LangAS AddrSpaceR = RHSType->getAs<BlockPointerType>()
9488	->getPointeeType()
9489	.getAddressSpace();
9490	Kind =
9491	AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
9492	return AssignConvertType::Compatible;
9493	}
9494	}
9495
9496	return AssignConvertType::Incompatible;
9497	}
9498
9499	// Conversions to block pointers.
9500	if (isa<BlockPointerType>(Val: LHSType)) {
9501	// U^ -> T^
9502	if (RHSType->isBlockPointerType()) {
9503	LangAS AddrSpaceL = LHSType->getAs<BlockPointerType>()
9504	->getPointeeType()
9505	.getAddressSpace();
9506	LangAS AddrSpaceR = RHSType->getAs<BlockPointerType>()
9507	->getPointeeType()
9508	.getAddressSpace();
9509	Kind = AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
9510	return checkBlockPointerTypesForAssignment(S&: *this, LHSType, RHSType);
9511	}
9512
9513	// int or null -> T^
9514	if (RHSType->isIntegerType()) {
9515	Kind = CK_IntegralToPointer; // FIXME: null
9516	return AssignConvertType::IntToBlockPointer;
9517	}
9518
9519	// id -> T^
9520	if (getLangOpts().ObjC && RHSType->isObjCIdType()) {
9521	Kind = CK_AnyPointerToBlockPointerCast;
9522	return AssignConvertType::Compatible;
9523	}
9524
9525	// void* -> T^
9526	if (const PointerType *RHSPT = RHSType->getAs<PointerType>())
9527	if (RHSPT->getPointeeType()->isVoidType()) {
9528	Kind = CK_AnyPointerToBlockPointerCast;
9529	return AssignConvertType::Compatible;
9530	}
9531
9532	return AssignConvertType::Incompatible;
9533	}
9534
9535	// Conversions to Objective-C pointers.
9536	if (isa<ObjCObjectPointerType>(Val: LHSType)) {
9537	// A* -> B*
9538	if (RHSType->isObjCObjectPointerType()) {
9539	Kind = CK_BitCast;
9540	AssignConvertType result =
9541	checkObjCPointerTypesForAssignment(S&: *this, LHSType, RHSType);
9542	if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
9543	result == AssignConvertType::Compatible &&
9544	!ObjC().CheckObjCARCUnavailableWeakConversion(castType: OrigLHSType, ExprType: RHSType))
9545	result = AssignConvertType::IncompatibleObjCWeakRef;
9546	return result;
9547	}
9548
9549	// int or null -> A*
9550	if (RHSType->isIntegerType()) {
9551	Kind = CK_IntegralToPointer; // FIXME: null
9552	return AssignConvertType::IntToPointer;
9553	}
9554
9555	// In general, C pointers are not compatible with ObjC object pointers,
9556	// with two exceptions:
9557	if (isa<PointerType>(Val: RHSType)) {
9558	Kind = CK_CPointerToObjCPointerCast;
9559
9560	// - conversions from 'void*'
9561	if (RHSType->isVoidPointerType()) {
9562	return AssignConvertType::Compatible;
9563	}
9564
9565	// - conversions to 'Class' from its redefinition type
9566	if (LHSType->isObjCClassType() &&
9567	Context.hasSameType(T1: RHSType,
9568	T2: Context.getObjCClassRedefinitionType())) {
9569	return AssignConvertType::Compatible;
9570	}
9571
9572	return AssignConvertType::IncompatiblePointer;
9573	}
9574
9575	// Only under strict condition T^ is compatible with an Objective-C pointer.
9576	if (RHSType->isBlockPointerType() &&
9577	LHSType->isBlockCompatibleObjCPointerType(ctx&: Context)) {
9578	if (ConvertRHS)
9579	maybeExtendBlockObject(E&: RHS);
9580	Kind = CK_BlockPointerToObjCPointerCast;
9581	return AssignConvertType::Compatible;
9582	}
9583
9584	return AssignConvertType::Incompatible;
9585	}
9586
9587	// Conversion to nullptr_t (C23 only)
9588	if (getLangOpts().C23 && LHSType->isNullPtrType() &&
9589	RHS.get()->isNullPointerConstant(Ctx&: Context,
9590	NPC: Expr::NPC_ValueDependentIsNull)) {
9591	// null -> nullptr_t
9592	Kind = CK_NullToPointer;
9593	return AssignConvertType::Compatible;
9594	}
9595
9596	// Conversions from pointers that are not covered by the above.
9597	if (isa<PointerType>(Val: RHSType)) {
9598	// T* -> _Bool
9599	if (LHSType == Context.BoolTy) {
9600	Kind = CK_PointerToBoolean;
9601	return AssignConvertType::Compatible;
9602	}
9603
9604	// T* -> int
9605	if (LHSType->isIntegerType()) {
9606	Kind = CK_PointerToIntegral;
9607	return AssignConvertType::PointerToInt;
9608	}
9609
9610	return AssignConvertType::Incompatible;
9611	}
9612
9613	// Conversions from Objective-C pointers that are not covered by the above.
9614	if (isa<ObjCObjectPointerType>(Val: RHSType)) {
9615	// T* -> _Bool
9616	if (LHSType == Context.BoolTy) {
9617	Kind = CK_PointerToBoolean;
9618	return AssignConvertType::Compatible;
9619	}
9620
9621	// T* -> int
9622	if (LHSType->isIntegerType()) {
9623	Kind = CK_PointerToIntegral;
9624	return AssignConvertType::PointerToInt;
9625	}
9626
9627	return AssignConvertType::Incompatible;
9628	}
9629
9630	// struct A -> struct B
9631	if (isa<TagType>(Val: LHSType) && isa<TagType>(Val: RHSType)) {
9632	if (Context.typesAreCompatible(T1: LHSType, T2: RHSType)) {
9633	Kind = CK_NoOp;
9634	return AssignConvertType::Compatible;
9635	}
9636	}
9637
9638	if (LHSType->isSamplerT() && RHSType->isIntegerType()) {
9639	Kind = CK_IntToOCLSampler;
9640	return AssignConvertType::Compatible;
9641	}
9642
9643	return AssignConvertType::Incompatible;
9644	}
9645
9646	/// Constructs a transparent union from an expression that is
9647	/// used to initialize the transparent union.
9648	static void ConstructTransparentUnion(Sema &S, ASTContext &C,
9649	ExprResult &EResult, QualType UnionType,
9650	FieldDecl *Field) {
9651	// Build an initializer list that designates the appropriate member
9652	// of the transparent union.
9653	Expr *E = EResult.get();
9654	InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(),
9655	E, SourceLocation());
9656	Initializer->setType(UnionType);
9657	Initializer->setInitializedFieldInUnion(Field);
9658
9659	// Build a compound literal constructing a value of the transparent
9660	// union type from this initializer list.
9661	TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(T: UnionType);
9662	EResult = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType,
9663	VK_PRValue, Initializer, false);
9664	}
9665
9666	AssignConvertType
9667	Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType,
9668	ExprResult &RHS) {
9669	QualType RHSType = RHS.get()->getType();
9670
9671	// If the ArgType is a Union type, we want to handle a potential
9672	// transparent_union GCC extension.
9673	const RecordType *UT = ArgType->getAsUnionType();
9674	if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>())
9675	return AssignConvertType::Incompatible;
9676
9677	// The field to initialize within the transparent union.
9678	RecordDecl *UD = UT->getDecl();
9679	FieldDecl *InitField = nullptr;
9680	// It's compatible if the expression matches any of the fields.
9681	for (auto *it : UD->fields()) {
9682	if (it->getType()->isPointerType()) {
9683	// If the transparent union contains a pointer type, we allow:
9684	// 1) void pointer
9685	// 2) null pointer constant
9686	if (RHSType->isPointerType())
9687	if (RHSType->castAs<PointerType>()->getPointeeType()->isVoidType()) {
9688	RHS = ImpCastExprToType(E: RHS.get(), Type: it->getType(), CK: CK_BitCast);
9689	InitField = it;
9690	break;
9691	}
9692
9693	if (RHS.get()->isNullPointerConstant(Ctx&: Context,
9694	NPC: Expr::NPC_ValueDependentIsNull)) {
9695	RHS = ImpCastExprToType(E: RHS.get(), Type: it->getType(),
9696	CK: CK_NullToPointer);
9697	InitField = it;
9698	break;
9699	}
9700	}
9701
9702	CastKind Kind;
9703	if (CheckAssignmentConstraints(LHSType: it->getType(), RHS, Kind) ==
9704	AssignConvertType::Compatible) {
9705	RHS = ImpCastExprToType(E: RHS.get(), Type: it->getType(), CK: Kind);
9706	InitField = it;
9707	break;
9708	}
9709	}
9710
9711	if (!InitField)
9712	return AssignConvertType::Incompatible;
9713
9714	ConstructTransparentUnion(S&: *this, C&: Context, EResult&: RHS, UnionType: ArgType, Field: InitField);
9715	return AssignConvertType::Compatible;
9716	}
9717
9718	AssignConvertType Sema::CheckSingleAssignmentConstraints(QualType LHSType,
9719	ExprResult &CallerRHS,
9720	bool Diagnose,
9721	bool DiagnoseCFAudited,
9722	bool ConvertRHS) {
9723	// We need to be able to tell the caller whether we diagnosed a problem, if
9724	// they ask us to issue diagnostics.
9725	assert((ConvertRHS || !Diagnose) && "can't indicate whether we diagnosed");
9726
9727	// If ConvertRHS is false, we want to leave the caller's RHS untouched. Sadly,
9728	// we can't avoid *all* modifications at the moment, so we need some somewhere
9729	// to put the updated value.
9730	ExprResult LocalRHS = CallerRHS;
9731	ExprResult &RHS = ConvertRHS ? CallerRHS : LocalRHS;
9732
9733	if (const auto *LHSPtrType = LHSType->getAs<PointerType>()) {
9734	if (const auto *RHSPtrType = RHS.get()->getType()->getAs<PointerType>()) {
9735	if (RHSPtrType->getPointeeType()->hasAttr(AK: attr::NoDeref) &&
9736	!LHSPtrType->getPointeeType()->hasAttr(AK: attr::NoDeref)) {
9737	Diag(Loc: RHS.get()->getExprLoc(),
9738	DiagID: diag::warn_noderef_to_dereferenceable_pointer)
9739	<< RHS.get()->getSourceRange();
9740	}
9741	}
9742	}
9743
9744	if (getLangOpts().CPlusPlus) {
9745	if (!LHSType->isRecordType() && !LHSType->isAtomicType()) {
9746	// C++ 5.17p3: If the left operand is not of class type, the
9747	// expression is implicitly converted (C++ 4) to the
9748	// cv-unqualified type of the left operand.
9749	QualType RHSType = RHS.get()->getType();
9750	if (Diagnose) {
9751	RHS = PerformImplicitConversion(From: RHS.get(), ToType: LHSType.getUnqualifiedType(),
9752	Action: AssignmentAction::Assigning);
9753	} else {
9754	ImplicitConversionSequence ICS =
9755	TryImplicitConversion(From: RHS.get(), ToType: LHSType.getUnqualifiedType(),
9756	/*SuppressUserConversions=*/false,
9757	AllowExplicit: AllowedExplicit::None,
9758	/*InOverloadResolution=*/false,
9759	/*CStyle=*/false,
9760	/*AllowObjCWritebackConversion=*/false);
9761	if (ICS.isFailure())
9762	return AssignConvertType::Incompatible;
9763	RHS = PerformImplicitConversion(From: RHS.get(), ToType: LHSType.getUnqualifiedType(),
9764	ICS, Action: AssignmentAction::Assigning);
9765	}
9766	if (RHS.isInvalid())
9767	return AssignConvertType::Incompatible;
9768	AssignConvertType result = AssignConvertType::Compatible;
9769	if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
9770	!ObjC().CheckObjCARCUnavailableWeakConversion(castType: LHSType, ExprType: RHSType))
9771	result = AssignConvertType::IncompatibleObjCWeakRef;
9772	return result;
9773	}
9774
9775	// FIXME: Currently, we fall through and treat C++ classes like C
9776	// structures.
9777	// FIXME: We also fall through for atomics; not sure what should
9778	// happen there, though.
9779	} else if (RHS.get()->getType() == Context.OverloadTy) {
9780	// As a set of extensions to C, we support overloading on functions. These
9781	// functions need to be resolved here.
9782	DeclAccessPair DAP;
9783	if (FunctionDecl *FD = ResolveAddressOfOverloadedFunction(
9784	AddressOfExpr: RHS.get(), TargetType: LHSType, /*Complain=*/false, Found&: DAP))
9785	RHS = FixOverloadedFunctionReference(E: RHS.get(), FoundDecl: DAP, Fn: FD);
9786	else
9787	return AssignConvertType::Incompatible;
9788	}
9789
9790	// This check seems unnatural, however it is necessary to ensure the proper
9791	// conversion of functions/arrays. If the conversion were done for all
9792	// DeclExpr's (created by ActOnIdExpression), it would mess up the unary
9793	// expressions that suppress this implicit conversion (&, sizeof). This needs
9794	// to happen before we check for null pointer conversions because C does not
9795	// undergo the same implicit conversions as C++ does above (by the calls to
9796	// TryImplicitConversion() and PerformImplicitConversion()) which insert the
9797	// lvalue to rvalue cast before checking for null pointer constraints. This
9798	// addresses code like: nullptr_t val; int *ptr; ptr = val;
9799	//
9800	// Suppress this for references: C++ 8.5.3p5.
9801	if (!LHSType->isReferenceType()) {
9802	// FIXME: We potentially allocate here even if ConvertRHS is false.
9803	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get(), Diagnose);
9804	if (RHS.isInvalid())
9805	return AssignConvertType::Incompatible;
9806	}
9807
9808	// The constraints are expressed in terms of the atomic, qualified, or
9809	// unqualified type of the LHS.
9810	QualType LHSTypeAfterConversion = LHSType.getAtomicUnqualifiedType();
9811
9812	// C99 6.5.16.1p1: the left operand is a pointer and the right is
9813	// a null pointer constant <C23>or its type is nullptr_t;</C23>.
9814	if ((LHSTypeAfterConversion->isPointerType() ||
9815	LHSTypeAfterConversion->isObjCObjectPointerType() ||
9816	LHSTypeAfterConversion->isBlockPointerType()) &&
9817	((getLangOpts().C23 && RHS.get()->getType()->isNullPtrType()) ||
9818	RHS.get()->isNullPointerConstant(Ctx&: Context,
9819	NPC: Expr::NPC_ValueDependentIsNull))) {
9820	AssignConvertType Ret = AssignConvertType::Compatible;
9821	if (Diagnose || ConvertRHS) {
9822	CastKind Kind;
9823	CXXCastPath Path;
9824	CheckPointerConversion(From: RHS.get(), ToType: LHSType, Kind, BasePath&: Path,
9825	/*IgnoreBaseAccess=*/false, Diagnose);
9826
9827	// If there is a conversion of some kind, check to see what kind of
9828	// pointer conversion happened so we can diagnose a C++ compatibility
9829	// diagnostic if the conversion is invalid. This only matters if the RHS
9830	// is some kind of void pointer. We have a carve-out when the RHS is from
9831	// a macro expansion because the use of a macro may indicate different
9832	// code between C and C++. Consider: char *s = NULL; where NULL is
9833	// defined as (void *)0 in C (which would be invalid in C++), but 0 in
9834	// C++, which is valid in C++.
9835	if (Kind != CK_NoOp && !getLangOpts().CPlusPlus &&
9836	!RHS.get()->getBeginLoc().isMacroID()) {
9837	QualType CanRHS =
9838	RHS.get()->getType().getCanonicalType().getUnqualifiedType();
9839	QualType CanLHS = LHSType.getCanonicalType().getUnqualifiedType();
9840	if (CanRHS->isVoidPointerType() && CanLHS->isPointerType()) {
9841	Ret = checkPointerTypesForAssignment(S&: *this, LHSType: CanLHS, RHSType: CanRHS,
9842	Loc: RHS.get()->getExprLoc());
9843	// Anything that's not considered perfectly compatible would be
9844	// incompatible in C++.
9845	if (Ret != AssignConvertType::Compatible)
9846	Ret = AssignConvertType::CompatibleVoidPtrToNonVoidPtr;
9847	}
9848	}
9849
9850	if (ConvertRHS)
9851	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: Kind, VK: VK_PRValue, BasePath: &Path);
9852	}
9853	return Ret;
9854	}
9855	// C23 6.5.16.1p1: the left operand has type atomic, qualified, or
9856	// unqualified bool, and the right operand is a pointer or its type is
9857	// nullptr_t.
9858	if (getLangOpts().C23 && LHSType->isBooleanType() &&
9859	RHS.get()->getType()->isNullPtrType()) {
9860	// NB: T* -> _Bool is handled in CheckAssignmentConstraints, this only
9861	// only handles nullptr -> _Bool due to needing an extra conversion
9862	// step.
9863	// We model this by converting from nullptr -> void * and then let the
9864	// conversion from void * -> _Bool happen naturally.
9865	if (Diagnose || ConvertRHS) {
9866	CastKind Kind;
9867	CXXCastPath Path;
9868	CheckPointerConversion(From: RHS.get(), ToType: Context.VoidPtrTy, Kind, BasePath&: Path,
9869	/*IgnoreBaseAccess=*/false, Diagnose);
9870	if (ConvertRHS)
9871	RHS = ImpCastExprToType(E: RHS.get(), Type: Context.VoidPtrTy, CK: Kind, VK: VK_PRValue,
9872	BasePath: &Path);
9873	}
9874	}
9875
9876	// OpenCL queue_t type assignment.
9877	if (LHSType->isQueueT() && RHS.get()->isNullPointerConstant(
9878	Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNull)) {
9879	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
9880	return AssignConvertType::Compatible;
9881	}
9882
9883	CastKind Kind;
9884	AssignConvertType result =
9885	CheckAssignmentConstraints(LHSType, RHS, Kind, ConvertRHS);
9886
9887	// C99 6.5.16.1p2: The value of the right operand is converted to the
9888	// type of the assignment expression.
9889	// CheckAssignmentConstraints allows the left-hand side to be a reference,
9890	// so that we can use references in built-in functions even in C.
9891	// The getNonReferenceType() call makes sure that the resulting expression
9892	// does not have reference type.
9893	if (result != AssignConvertType::Incompatible &&
9894	RHS.get()->getType() != LHSType) {
9895	QualType Ty = LHSType.getNonLValueExprType(Context);
9896	Expr *E = RHS.get();
9897
9898	// Check for various Objective-C errors. If we are not reporting
9899	// diagnostics and just checking for errors, e.g., during overload
9900	// resolution, return Incompatible to indicate the failure.
9901	if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
9902	ObjC().CheckObjCConversion(castRange: SourceRange(), castType: Ty, op&: E,
9903	CCK: CheckedConversionKind::Implicit, Diagnose,
9904	DiagnoseCFAudited) != SemaObjC::ACR_okay) {
9905	if (!Diagnose)
9906	return AssignConvertType::Incompatible;
9907	}
9908	if (getLangOpts().ObjC &&
9909	(ObjC().CheckObjCBridgeRelatedConversions(Loc: E->getBeginLoc(), DestType: LHSType,
9910	SrcType: E->getType(), SrcExpr&: E, Diagnose) ||
9911	ObjC().CheckConversionToObjCLiteral(DstType: LHSType, SrcExpr&: E, Diagnose))) {
9912	if (!Diagnose)
9913	return AssignConvertType::Incompatible;
9914	// Replace the expression with a corrected version and continue so we
9915	// can find further errors.
9916	RHS = E;
9917	return AssignConvertType::Compatible;
9918	}
9919
9920	if (ConvertRHS)
9921	RHS = ImpCastExprToType(E, Type: Ty, CK: Kind);
9922	}
9923
9924	return result;
9925	}
9926
9927	namespace {
9928	/// The original operand to an operator, prior to the application of the usual
9929	/// arithmetic conversions and converting the arguments of a builtin operator
9930	/// candidate.
9931	struct OriginalOperand {
9932	explicit OriginalOperand(Expr *Op) : Orig(Op), Conversion(nullptr) {
9933	if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(Val: Op))
9934	Op = MTE->getSubExpr();
9935	if (auto *BTE = dyn_cast<CXXBindTemporaryExpr>(Val: Op))
9936	Op = BTE->getSubExpr();
9937	if (auto *ICE = dyn_cast<ImplicitCastExpr>(Val: Op)) {
9938	Orig = ICE->getSubExprAsWritten();
9939	Conversion = ICE->getConversionFunction();
9940	}
9941	}
9942
9943	QualType getType() const { return Orig->getType(); }
9944
9945	Expr *Orig;
9946	NamedDecl *Conversion;
9947	};
9948	}
9949
9950	QualType Sema::InvalidOperands(SourceLocation Loc, ExprResult &LHS,
9951	ExprResult &RHS) {
9952	OriginalOperand OrigLHS(LHS.get()), OrigRHS(RHS.get());
9953
9954	Diag(Loc, DiagID: diag::err_typecheck_invalid_operands)
9955	<< OrigLHS.getType() << OrigRHS.getType()
9956	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9957
9958	// If a user-defined conversion was applied to either of the operands prior
9959	// to applying the built-in operator rules, tell the user about it.
9960	if (OrigLHS.Conversion) {
9961	Diag(Loc: OrigLHS.Conversion->getLocation(),
9962	DiagID: diag::note_typecheck_invalid_operands_converted)
9963	<< 0 << LHS.get()->getType();
9964	}
9965	if (OrigRHS.Conversion) {
9966	Diag(Loc: OrigRHS.Conversion->getLocation(),
9967	DiagID: diag::note_typecheck_invalid_operands_converted)
9968	<< 1 << RHS.get()->getType();
9969	}
9970
9971	return QualType();
9972	}
9973
9974	QualType Sema::InvalidLogicalVectorOperands(SourceLocation Loc, ExprResult &LHS,
9975	ExprResult &RHS) {
9976	QualType LHSType = LHS.get()->IgnoreImpCasts()->getType();
9977	QualType RHSType = RHS.get()->IgnoreImpCasts()->getType();
9978
9979	bool LHSNatVec = LHSType->isVectorType();
9980	bool RHSNatVec = RHSType->isVectorType();
9981
9982	if (!(LHSNatVec && RHSNatVec)) {
9983	Expr *Vector = LHSNatVec ? LHS.get() : RHS.get();
9984	Expr *NonVector = !LHSNatVec ? LHS.get() : RHS.get();
9985	Diag(Loc, DiagID: diag::err_typecheck_logical_vector_expr_gnu_cpp_restrict)
9986	<< 0 << Vector->getType() << NonVector->IgnoreImpCasts()->getType()
9987	<< Vector->getSourceRange();
9988	return QualType();
9989	}
9990
9991	Diag(Loc, DiagID: diag::err_typecheck_logical_vector_expr_gnu_cpp_restrict)
9992	<< 1 << LHSType << RHSType << LHS.get()->getSourceRange()
9993	<< RHS.get()->getSourceRange();
9994
9995	return QualType();
9996	}
9997
9998	/// Try to convert a value of non-vector type to a vector type by converting
9999	/// the type to the element type of the vector and then performing a splat.
10000	/// If the language is OpenCL, we only use conversions that promote scalar
10001	/// rank; for C, Obj-C, and C++ we allow any real scalar conversion except
10002	/// for float->int.
10003	///
10004	/// OpenCL V2.0 6.2.6.p2:
10005	/// An error shall occur if any scalar operand type has greater rank
10006	/// than the type of the vector element.
10007	///
10008	/// \param scalar - if non-null, actually perform the conversions
10009	/// \return true if the operation fails (but without diagnosing the failure)
10010	static bool tryVectorConvertAndSplat(Sema &S, ExprResult *scalar,
10011	QualType scalarTy,
10012	QualType vectorEltTy,
10013	QualType vectorTy,
10014	unsigned &DiagID) {
10015	// The conversion to apply to the scalar before splatting it,
10016	// if necessary.
10017	CastKind scalarCast = CK_NoOp;
10018
10019	if (vectorEltTy->isBooleanType() && scalarTy->isIntegralType(Ctx: S.Context)) {
10020	scalarCast = CK_IntegralToBoolean;
10021	} else if (vectorEltTy->isIntegralType(Ctx: S.Context)) {
10022	if (S.getLangOpts().OpenCL && (scalarTy->isRealFloatingType() ||
10023	(scalarTy->isIntegerType() &&
10024	S.Context.getIntegerTypeOrder(LHS: vectorEltTy, RHS: scalarTy) < 0))) {
10025	DiagID = diag::err_opencl_scalar_type_rank_greater_than_vector_type;
10026	return true;
10027	}
10028	if (!scalarTy->isIntegralType(Ctx: S.Context))
10029	return true;
10030	scalarCast = CK_IntegralCast;
10031	} else if (vectorEltTy->isRealFloatingType()) {
10032	if (scalarTy->isRealFloatingType()) {
10033	if (S.getLangOpts().OpenCL &&
10034	S.Context.getFloatingTypeOrder(LHS: vectorEltTy, RHS: scalarTy) < 0) {
10035	DiagID = diag::err_opencl_scalar_type_rank_greater_than_vector_type;
10036	return true;
10037	}
10038	scalarCast = CK_FloatingCast;
10039	}
10040	else if (scalarTy->isIntegralType(Ctx: S.Context))
10041	scalarCast = CK_IntegralToFloating;
10042	else
10043	return true;
10044	} else {
10045	return true;
10046	}
10047
10048	// Adjust scalar if desired.
10049	if (scalar) {
10050	if (scalarCast != CK_NoOp)
10051	*scalar = S.ImpCastExprToType(E: scalar->get(), Type: vectorEltTy, CK: scalarCast);
10052	*scalar = S.ImpCastExprToType(E: scalar->get(), Type: vectorTy, CK: CK_VectorSplat);
10053	}
10054	return false;
10055	}
10056
10057	/// Convert vector E to a vector with the same number of elements but different
10058	/// element type.
10059	static ExprResult convertVector(Expr *E, QualType ElementType, Sema &S) {
10060	const auto *VecTy = E->getType()->getAs<VectorType>();
10061	assert(VecTy && "Expression E must be a vector");
10062	QualType NewVecTy =
10063	VecTy->isExtVectorType()
10064	? S.Context.getExtVectorType(VectorType: ElementType, NumElts: VecTy->getNumElements())
10065	: S.Context.getVectorType(VectorType: ElementType, NumElts: VecTy->getNumElements(),
10066	VecKind: VecTy->getVectorKind());
10067
10068	// Look through the implicit cast. Return the subexpression if its type is
10069	// NewVecTy.
10070	if (auto *ICE = dyn_cast<ImplicitCastExpr>(Val: E))
10071	if (ICE->getSubExpr()->getType() == NewVecTy)
10072	return ICE->getSubExpr();
10073
10074	auto Cast = ElementType->isIntegerType() ? CK_IntegralCast : CK_FloatingCast;
10075	return S.ImpCastExprToType(E, Type: NewVecTy, CK: Cast);
10076	}
10077
10078	/// Test if a (constant) integer Int can be casted to another integer type
10079	/// IntTy without losing precision.
10080	static bool canConvertIntToOtherIntTy(Sema &S, ExprResult *Int,
10081	QualType OtherIntTy) {
10082	if (Int->get()->containsErrors())
10083	return false;
10084
10085	QualType IntTy = Int->get()->getType().getUnqualifiedType();
10086
10087	// Reject cases where the value of the Int is unknown as that would
10088	// possibly cause truncation, but accept cases where the scalar can be
10089	// demoted without loss of precision.
10090	Expr::EvalResult EVResult;
10091	bool CstInt = Int->get()->EvaluateAsInt(Result&: EVResult, Ctx: S.Context);
10092	int Order = S.Context.getIntegerTypeOrder(LHS: OtherIntTy, RHS: IntTy);
10093	bool IntSigned = IntTy->hasSignedIntegerRepresentation();
10094	bool OtherIntSigned = OtherIntTy->hasSignedIntegerRepresentation();
10095
10096	if (CstInt) {
10097	// If the scalar is constant and is of a higher order and has more active
10098	// bits that the vector element type, reject it.
10099	llvm::APSInt Result = EVResult.Val.getInt();
10100	unsigned NumBits = IntSigned
10101	? (Result.isNegative() ? Result.getSignificantBits()
10102	: Result.getActiveBits())
10103	: Result.getActiveBits();
10104	if (Order < 0 && S.Context.getIntWidth(T: OtherIntTy) < NumBits)
10105	return true;
10106
10107	// If the signedness of the scalar type and the vector element type
10108	// differs and the number of bits is greater than that of the vector
10109	// element reject it.
10110	return (IntSigned != OtherIntSigned &&
10111	NumBits > S.Context.getIntWidth(T: OtherIntTy));
10112	}
10113
10114	// Reject cases where the value of the scalar is not constant and it's
10115	// order is greater than that of the vector element type.
10116	return (Order < 0);
10117	}
10118
10119	/// Test if a (constant) integer Int can be casted to floating point type
10120	/// FloatTy without losing precision.
10121	static bool canConvertIntTyToFloatTy(Sema &S, ExprResult *Int,
10122	QualType FloatTy) {
10123	if (Int->get()->containsErrors())
10124	return false;
10125
10126	QualType IntTy = Int->get()->getType().getUnqualifiedType();
10127
10128	// Determine if the integer constant can be expressed as a floating point
10129	// number of the appropriate type.
10130	Expr::EvalResult EVResult;
10131	bool CstInt = Int->get()->EvaluateAsInt(Result&: EVResult, Ctx: S.Context);
10132
10133	uint64_t Bits = 0;
10134	if (CstInt) {
10135	// Reject constants that would be truncated if they were converted to
10136	// the floating point type. Test by simple to/from conversion.
10137	// FIXME: Ideally the conversion to an APFloat and from an APFloat
10138	// could be avoided if there was a convertFromAPInt method
10139	// which could signal back if implicit truncation occurred.
10140	llvm::APSInt Result = EVResult.Val.getInt();
10141	llvm::APFloat Float(S.Context.getFloatTypeSemantics(T: FloatTy));
10142	Float.convertFromAPInt(Input: Result, IsSigned: IntTy->hasSignedIntegerRepresentation(),
10143	RM: llvm::APFloat::rmTowardZero);
10144	llvm::APSInt ConvertBack(S.Context.getIntWidth(T: IntTy),
10145	!IntTy->hasSignedIntegerRepresentation());
10146	bool Ignored = false;
10147	Float.convertToInteger(Result&: ConvertBack, RM: llvm::APFloat::rmNearestTiesToEven,
10148	IsExact: &Ignored);
10149	if (Result != ConvertBack)
10150	return true;
10151	} else {
10152	// Reject types that cannot be fully encoded into the mantissa of
10153	// the float.
10154	Bits = S.Context.getTypeSize(T: IntTy);
10155	unsigned FloatPrec = llvm::APFloat::semanticsPrecision(
10156	S.Context.getFloatTypeSemantics(T: FloatTy));
10157	if (Bits > FloatPrec)
10158	return true;
10159	}
10160
10161	return false;
10162	}
10163
10164	/// Attempt to convert and splat Scalar into a vector whose types matches
10165	/// Vector following GCC conversion rules. The rule is that implicit
10166	/// conversion can occur when Scalar can be casted to match Vector's element
10167	/// type without causing truncation of Scalar.
10168	static bool tryGCCVectorConvertAndSplat(Sema &S, ExprResult *Scalar,
10169	ExprResult *Vector) {
10170	QualType ScalarTy = Scalar->get()->getType().getUnqualifiedType();
10171	QualType VectorTy = Vector->get()->getType().getUnqualifiedType();
10172	QualType VectorEltTy;
10173
10174	if (const auto *VT = VectorTy->getAs<VectorType>()) {
10175	assert(!isa<ExtVectorType>(VT) &&
10176	"ExtVectorTypes should not be handled here!");
10177	VectorEltTy = VT->getElementType();
10178	} else if (VectorTy->isSveVLSBuiltinType()) {
10179	VectorEltTy =
10180	VectorTy->castAs<BuiltinType>()->getSveEltType(Ctx: S.getASTContext());
10181	} else {
10182	llvm_unreachable("Only Fixed-Length and SVE Vector types are handled here");
10183	}
10184
10185	// Reject cases where the vector element type or the scalar element type are
10186	// not integral or floating point types.
10187	if (!VectorEltTy->isArithmeticType() || !ScalarTy->isArithmeticType())
10188	return true;
10189
10190	// The conversion to apply to the scalar before splatting it,
10191	// if necessary.
10192	CastKind ScalarCast = CK_NoOp;
10193
10194	// Accept cases where the vector elements are integers and the scalar is
10195	// an integer.
10196	// FIXME: Notionally if the scalar was a floating point value with a precise
10197	// integral representation, we could cast it to an appropriate integer
10198	// type and then perform the rest of the checks here. GCC will perform
10199	// this conversion in some cases as determined by the input language.
10200	// We should accept it on a language independent basis.
10201	if (VectorEltTy->isIntegralType(Ctx: S.Context) &&
10202	ScalarTy->isIntegralType(Ctx: S.Context) &&
10203	S.Context.getIntegerTypeOrder(LHS: VectorEltTy, RHS: ScalarTy)) {
10204
10205	if (canConvertIntToOtherIntTy(S, Int: Scalar, OtherIntTy: VectorEltTy))
10206	return true;
10207
10208	ScalarCast = CK_IntegralCast;
10209	} else if (VectorEltTy->isIntegralType(Ctx: S.Context) &&
10210	ScalarTy->isRealFloatingType()) {
10211	if (S.Context.getTypeSize(T: VectorEltTy) == S.Context.getTypeSize(T: ScalarTy))
10212	ScalarCast = CK_FloatingToIntegral;
10213	else
10214	return true;
10215	} else if (VectorEltTy->isRealFloatingType()) {
10216	if (ScalarTy->isRealFloatingType()) {
10217
10218	// Reject cases where the scalar type is not a constant and has a higher
10219	// Order than the vector element type.
10220	llvm::APFloat Result(0.0);
10221
10222	// Determine whether this is a constant scalar. In the event that the
10223	// value is dependent (and thus cannot be evaluated by the constant
10224	// evaluator), skip the evaluation. This will then diagnose once the
10225	// expression is instantiated.
10226	bool CstScalar = Scalar->get()->isValueDependent() ||
10227	Scalar->get()->EvaluateAsFloat(Result, Ctx: S.Context);
10228	int Order = S.Context.getFloatingTypeOrder(LHS: VectorEltTy, RHS: ScalarTy);
10229	if (!CstScalar && Order < 0)
10230	return true;
10231
10232	// If the scalar cannot be safely casted to the vector element type,
10233	// reject it.
10234	if (CstScalar) {
10235	bool Truncated = false;
10236	Result.convert(ToSemantics: S.Context.getFloatTypeSemantics(T: VectorEltTy),
10237	RM: llvm::APFloat::rmNearestTiesToEven, losesInfo: &Truncated);
10238	if (Truncated)
10239	return true;
10240	}
10241
10242	ScalarCast = CK_FloatingCast;
10243	} else if (ScalarTy->isIntegralType(Ctx: S.Context)) {
10244	if (canConvertIntTyToFloatTy(S, Int: Scalar, FloatTy: VectorEltTy))
10245	return true;
10246
10247	ScalarCast = CK_IntegralToFloating;
10248	} else
10249	return true;
10250	} else if (ScalarTy->isEnumeralType())
10251	return true;
10252
10253	// Adjust scalar if desired.
10254	if (ScalarCast != CK_NoOp)
10255	*Scalar = S.ImpCastExprToType(E: Scalar->get(), Type: VectorEltTy, CK: ScalarCast);
10256	*Scalar = S.ImpCastExprToType(E: Scalar->get(), Type: VectorTy, CK: CK_VectorSplat);
10257	return false;
10258	}
10259
10260	QualType Sema::CheckVectorOperands(ExprResult &LHS, ExprResult &RHS,
10261	SourceLocation Loc, bool IsCompAssign,
10262	bool AllowBothBool,
10263	bool AllowBoolConversions,
10264	bool AllowBoolOperation,
10265	bool ReportInvalid) {
10266	if (!IsCompAssign) {
10267	LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
10268	if (LHS.isInvalid())
10269	return QualType();
10270	}
10271	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
10272	if (RHS.isInvalid())
10273	return QualType();
10274
10275	// For conversion purposes, we ignore any qualifiers.
10276	// For example, "const float" and "float" are equivalent.
10277	QualType LHSType = LHS.get()->getType().getUnqualifiedType();
10278	QualType RHSType = RHS.get()->getType().getUnqualifiedType();
10279
10280	const VectorType *LHSVecType = LHSType->getAs<VectorType>();
10281	const VectorType *RHSVecType = RHSType->getAs<VectorType>();
10282	assert(LHSVecType || RHSVecType);
10283
10284	if (getLangOpts().HLSL)
10285	return HLSL().handleVectorBinOpConversion(LHS, RHS, LHSType, RHSType,
10286	IsCompAssign);
10287
10288	// Any operation with MFloat8 type is only possible with C intrinsics
10289	if ((LHSVecType && LHSVecType->getElementType()->isMFloat8Type()) ||
10290	(RHSVecType && RHSVecType->getElementType()->isMFloat8Type()))
10291	return InvalidOperands(Loc, LHS, RHS);
10292
10293	// AltiVec-style "vector bool op vector bool" combinations are allowed
10294	// for some operators but not others.
10295	if (!AllowBothBool && LHSVecType &&
10296	LHSVecType->getVectorKind() == VectorKind::AltiVecBool && RHSVecType &&
10297	RHSVecType->getVectorKind() == VectorKind::AltiVecBool)
10298	return ReportInvalid ? InvalidOperands(Loc, LHS, RHS) : QualType();
10299
10300	// This operation may not be performed on boolean vectors.
10301	if (!AllowBoolOperation &&
10302	(LHSType->isExtVectorBoolType() || RHSType->isExtVectorBoolType()))
10303	return ReportInvalid ? InvalidOperands(Loc, LHS, RHS) : QualType();
10304
10305	// If the vector types are identical, return.
10306	if (Context.hasSameType(T1: LHSType, T2: RHSType))
10307	return Context.getCommonSugaredType(X: LHSType, Y: RHSType);
10308
10309	// If we have compatible AltiVec and GCC vector types, use the AltiVec type.
10310	if (LHSVecType && RHSVecType &&
10311	Context.areCompatibleVectorTypes(FirstVec: LHSType, SecondVec: RHSType)) {
10312	if (isa<ExtVectorType>(Val: LHSVecType)) {
10313	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_BitCast);
10314	return LHSType;
10315	}
10316
10317	if (!IsCompAssign)
10318	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_BitCast);
10319	return RHSType;
10320	}
10321
10322	// AllowBoolConversions says that bool and non-bool AltiVec vectors
10323	// can be mixed, with the result being the non-bool type. The non-bool
10324	// operand must have integer element type.
10325	if (AllowBoolConversions && LHSVecType && RHSVecType &&
10326	LHSVecType->getNumElements() == RHSVecType->getNumElements() &&
10327	(Context.getTypeSize(T: LHSVecType->getElementType()) ==
10328	Context.getTypeSize(T: RHSVecType->getElementType()))) {
10329	if (LHSVecType->getVectorKind() == VectorKind::AltiVecVector &&
10330	LHSVecType->getElementType()->isIntegerType() &&
10331	RHSVecType->getVectorKind() == VectorKind::AltiVecBool) {
10332	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_BitCast);
10333	return LHSType;
10334	}
10335	if (!IsCompAssign &&
10336	LHSVecType->getVectorKind() == VectorKind::AltiVecBool &&
10337	RHSVecType->getVectorKind() == VectorKind::AltiVecVector &&
10338	RHSVecType->getElementType()->isIntegerType()) {
10339	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_BitCast);
10340	return RHSType;
10341	}
10342	}
10343
10344	// Expressions containing fixed-length and sizeless SVE/RVV vectors are
10345	// invalid since the ambiguity can affect the ABI.
10346	auto IsSveRVVConversion = [](QualType FirstType, QualType SecondType,
10347	unsigned &SVEorRVV) {
10348	const VectorType *VecType = SecondType->getAs<VectorType>();
10349	SVEorRVV = 0;
10350	if (FirstType->isSizelessBuiltinType() && VecType) {
10351	if (VecType->getVectorKind() == VectorKind::SveFixedLengthData ||
10352	VecType->getVectorKind() == VectorKind::SveFixedLengthPredicate)
10353	return true;
10354	if (VecType->getVectorKind() == VectorKind::RVVFixedLengthData ||
10355	VecType->getVectorKind() == VectorKind::RVVFixedLengthMask ||
10356	VecType->getVectorKind() == VectorKind::RVVFixedLengthMask_1 ||
10357	VecType->getVectorKind() == VectorKind::RVVFixedLengthMask_2 ||
10358	VecType->getVectorKind() == VectorKind::RVVFixedLengthMask_4) {
10359	SVEorRVV = 1;
10360	return true;
10361	}
10362	}
10363
10364	return false;
10365	};
10366
10367	unsigned SVEorRVV;
10368	if (IsSveRVVConversion(LHSType, RHSType, SVEorRVV) ||
10369	IsSveRVVConversion(RHSType, LHSType, SVEorRVV)) {
10370	Diag(Loc, DiagID: diag::err_typecheck_sve_rvv_ambiguous)
10371	<< SVEorRVV << LHSType << RHSType;
10372	return QualType();
10373	}
10374
10375	// Expressions containing GNU and SVE or RVV (fixed or sizeless) vectors are
10376	// invalid since the ambiguity can affect the ABI.
10377	auto IsSveRVVGnuConversion = [](QualType FirstType, QualType SecondType,
10378	unsigned &SVEorRVV) {
10379	const VectorType *FirstVecType = FirstType->getAs<VectorType>();
10380	const VectorType *SecondVecType = SecondType->getAs<VectorType>();
10381
10382	SVEorRVV = 0;
10383	if (FirstVecType && SecondVecType) {
10384	if (FirstVecType->getVectorKind() == VectorKind::Generic) {
10385	if (SecondVecType->getVectorKind() == VectorKind::SveFixedLengthData ||
10386	SecondVecType->getVectorKind() ==
10387	VectorKind::SveFixedLengthPredicate)
10388	return true;
10389	if (SecondVecType->getVectorKind() == VectorKind::RVVFixedLengthData ||
10390	SecondVecType->getVectorKind() == VectorKind::RVVFixedLengthMask ||
10391	SecondVecType->getVectorKind() ==
10392	VectorKind::RVVFixedLengthMask_1 ||
10393	SecondVecType->getVectorKind() ==
10394	VectorKind::RVVFixedLengthMask_2 ||
10395	SecondVecType->getVectorKind() ==
10396	VectorKind::RVVFixedLengthMask_4) {
10397	SVEorRVV = 1;
10398	return true;
10399	}
10400	}
10401	return false;
10402	}
10403
10404	if (SecondVecType &&
10405	SecondVecType->getVectorKind() == VectorKind::Generic) {
10406	if (FirstType->isSVESizelessBuiltinType())
10407	return true;
10408	if (FirstType->isRVVSizelessBuiltinType()) {
10409	SVEorRVV = 1;
10410	return true;
10411	}
10412	}
10413
10414	return false;
10415	};
10416
10417	if (IsSveRVVGnuConversion(LHSType, RHSType, SVEorRVV) ||
10418	IsSveRVVGnuConversion(RHSType, LHSType, SVEorRVV)) {
10419	Diag(Loc, DiagID: diag::err_typecheck_sve_rvv_gnu_ambiguous)
10420	<< SVEorRVV << LHSType << RHSType;
10421	return QualType();
10422	}
10423
10424	// If there's a vector type and a scalar, try to convert the scalar to
10425	// the vector element type and splat.
10426	unsigned DiagID = diag::err_typecheck_vector_not_convertable;
10427	if (!RHSVecType) {
10428	if (isa<ExtVectorType>(Val: LHSVecType)) {
10429	if (!tryVectorConvertAndSplat(S&: *this, scalar: &RHS, scalarTy: RHSType,
10430	vectorEltTy: LHSVecType->getElementType(), vectorTy: LHSType,
10431	DiagID))
10432	return LHSType;
10433	} else {
10434	if (!tryGCCVectorConvertAndSplat(S&: *this, Scalar: &RHS, Vector: &LHS))
10435	return LHSType;
10436	}
10437	}
10438	if (!LHSVecType) {
10439	if (isa<ExtVectorType>(Val: RHSVecType)) {
10440	if (!tryVectorConvertAndSplat(S&: *this, scalar: (IsCompAssign ? nullptr : &LHS),
10441	scalarTy: LHSType, vectorEltTy: RHSVecType->getElementType(),
10442	vectorTy: RHSType, DiagID))
10443	return RHSType;
10444	} else {
10445	if (LHS.get()->isLValue() ||
10446	!tryGCCVectorConvertAndSplat(S&: *this, Scalar: &LHS, Vector: &RHS))
10447	return RHSType;
10448	}
10449	}
10450
10451	// FIXME: The code below also handles conversion between vectors and
10452	// non-scalars, we should break this down into fine grained specific checks
10453	// and emit proper diagnostics.
10454	QualType VecType = LHSVecType ? LHSType : RHSType;
10455	const VectorType *VT = LHSVecType ? LHSVecType : RHSVecType;
10456	QualType OtherType = LHSVecType ? RHSType : LHSType;
10457	ExprResult *OtherExpr = LHSVecType ? &RHS : &LHS;
10458	if (isLaxVectorConversion(srcTy: OtherType, destTy: VecType)) {
10459	if (Context.getTargetInfo().getTriple().isPPC() &&
10460	anyAltivecTypes(SrcTy: RHSType, DestTy: LHSType) &&
10461	!Context.areCompatibleVectorTypes(FirstVec: RHSType, SecondVec: LHSType))
10462	Diag(Loc, DiagID: diag::warn_deprecated_lax_vec_conv_all) << RHSType << LHSType;
10463	// If we're allowing lax vector conversions, only the total (data) size
10464	// needs to be the same. For non compound assignment, if one of the types is
10465	// scalar, the result is always the vector type.
10466	if (!IsCompAssign) {
10467	*OtherExpr = ImpCastExprToType(E: OtherExpr->get(), Type: VecType, CK: CK_BitCast);
10468	return VecType;
10469	// In a compound assignment, lhs += rhs, 'lhs' is a lvalue src, forbidding
10470	// any implicit cast. Here, the 'rhs' should be implicit casted to 'lhs'
10471	// type. Note that this is already done by non-compound assignments in
10472	// CheckAssignmentConstraints. If it's a scalar type, only bitcast for
10473	// <1 x T> -> T. The result is also a vector type.
10474	} else if (OtherType->isExtVectorType() || OtherType->isVectorType() ||
10475	(OtherType->isScalarType() && VT->getNumElements() == 1)) {
10476	ExprResult *RHSExpr = &RHS;
10477	*RHSExpr = ImpCastExprToType(E: RHSExpr->get(), Type: LHSType, CK: CK_BitCast);
10478	return VecType;
10479	}
10480	}
10481
10482	// Okay, the expression is invalid.
10483
10484	// If there's a non-vector, non-real operand, diagnose that.
10485	if ((!RHSVecType && !RHSType->isRealType()) ||
10486	(!LHSVecType && !LHSType->isRealType())) {
10487	Diag(Loc, DiagID: diag::err_typecheck_vector_not_convertable_non_scalar)
10488	<< LHSType << RHSType
10489	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
10490	return QualType();
10491	}
10492
10493	// OpenCL V1.1 6.2.6.p1:
10494	// If the operands are of more than one vector type, then an error shall
10495	// occur. Implicit conversions between vector types are not permitted, per
10496	// section 6.2.1.
10497	if (getLangOpts().OpenCL &&
10498	RHSVecType && isa<ExtVectorType>(Val: RHSVecType) &&
10499	LHSVecType && isa<ExtVectorType>(Val: LHSVecType)) {
10500	Diag(Loc, DiagID: diag::err_opencl_implicit_vector_conversion) << LHSType
10501	<< RHSType;
10502	return QualType();
10503	}
10504
10505
10506	// If there is a vector type that is not a ExtVector and a scalar, we reach
10507	// this point if scalar could not be converted to the vector's element type
10508	// without truncation.
10509	if ((RHSVecType && !isa<ExtVectorType>(Val: RHSVecType)) ||
10510	(LHSVecType && !isa<ExtVectorType>(Val: LHSVecType))) {
10511	QualType Scalar = LHSVecType ? RHSType : LHSType;
10512	QualType Vector = LHSVecType ? LHSType : RHSType;
10513	unsigned ScalarOrVector = LHSVecType && RHSVecType ? 1 : 0;
10514	Diag(Loc,
10515	DiagID: diag::err_typecheck_vector_not_convertable_implict_truncation)
10516	<< ScalarOrVector << Scalar << Vector;
10517
10518	return QualType();
10519	}
10520
10521	// Otherwise, use the generic diagnostic.
10522	Diag(Loc, DiagID)
10523	<< LHSType << RHSType
10524	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
10525	return QualType();
10526	}
10527
10528	QualType Sema::CheckSizelessVectorOperands(ExprResult &LHS, ExprResult &RHS,
10529	SourceLocation Loc,
10530	bool IsCompAssign,
10531	ArithConvKind OperationKind) {
10532	if (!IsCompAssign) {
10533	LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
10534	if (LHS.isInvalid())
10535	return QualType();
10536	}
10537	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
10538	if (RHS.isInvalid())
10539	return QualType();
10540
10541	QualType LHSType = LHS.get()->getType().getUnqualifiedType();
10542	QualType RHSType = RHS.get()->getType().getUnqualifiedType();
10543
10544	const BuiltinType *LHSBuiltinTy = LHSType->getAs<BuiltinType>();
10545	const BuiltinType *RHSBuiltinTy = RHSType->getAs<BuiltinType>();
10546
10547	unsigned DiagID = diag::err_typecheck_invalid_operands;
10548	if ((OperationKind == ArithConvKind::Arithmetic) &&
10549	((LHSBuiltinTy && LHSBuiltinTy->isSVEBool()) ||
10550	(RHSBuiltinTy && RHSBuiltinTy->isSVEBool()))) {
10551	Diag(Loc, DiagID) << LHSType << RHSType << LHS.get()->getSourceRange()
10552	<< RHS.get()->getSourceRange();
10553	return QualType();
10554	}
10555
10556	if (Context.hasSameType(T1: LHSType, T2: RHSType))
10557	return LHSType;
10558
10559	if (LHSType->isSveVLSBuiltinType() && !RHSType->isSveVLSBuiltinType()) {
10560	if (!tryGCCVectorConvertAndSplat(S&: *this, Scalar: &RHS, Vector: &LHS))
10561	return LHSType;
10562	}
10563	if (RHSType->isSveVLSBuiltinType() && !LHSType->isSveVLSBuiltinType()) {
10564	if (LHS.get()->isLValue() ||
10565	!tryGCCVectorConvertAndSplat(S&: *this, Scalar: &LHS, Vector: &RHS))
10566	return RHSType;
10567	}
10568
10569	if ((!LHSType->isSveVLSBuiltinType() && !LHSType->isRealType()) ||
10570	(!RHSType->isSveVLSBuiltinType() && !RHSType->isRealType())) {
10571	Diag(Loc, DiagID: diag::err_typecheck_vector_not_convertable_non_scalar)
10572	<< LHSType << RHSType << LHS.get()->getSourceRange()
10573	<< RHS.get()->getSourceRange();
10574	return QualType();
10575	}
10576
10577	if (LHSType->isSveVLSBuiltinType() && RHSType->isSveVLSBuiltinType() &&
10578	Context.getBuiltinVectorTypeInfo(VecTy: LHSBuiltinTy).EC !=
10579	Context.getBuiltinVectorTypeInfo(VecTy: RHSBuiltinTy).EC) {
10580	Diag(Loc, DiagID: diag::err_typecheck_vector_lengths_not_equal)
10581	<< LHSType << RHSType << LHS.get()->getSourceRange()
10582	<< RHS.get()->getSourceRange();
10583	return QualType();
10584	}
10585
10586	if (LHSType->isSveVLSBuiltinType() || RHSType->isSveVLSBuiltinType()) {
10587	QualType Scalar = LHSType->isSveVLSBuiltinType() ? RHSType : LHSType;
10588	QualType Vector = LHSType->isSveVLSBuiltinType() ? LHSType : RHSType;
10589	bool ScalarOrVector =
10590	LHSType->isSveVLSBuiltinType() && RHSType->isSveVLSBuiltinType();
10591
10592	Diag(Loc, DiagID: diag::err_typecheck_vector_not_convertable_implict_truncation)
10593	<< ScalarOrVector << Scalar << Vector;
10594
10595	return QualType();
10596	}
10597
10598	Diag(Loc, DiagID) << LHSType << RHSType << LHS.get()->getSourceRange()
10599	<< RHS.get()->getSourceRange();
10600	return QualType();
10601	}
10602
10603	// checkArithmeticNull - Detect when a NULL constant is used improperly in an
10604	// expression. These are mainly cases where the null pointer is used as an
10605	// integer instead of a pointer.
10606	static void checkArithmeticNull(Sema &S, ExprResult &LHS, ExprResult &RHS,
10607	SourceLocation Loc, bool IsCompare) {
10608	// The canonical way to check for a GNU null is with isNullPointerConstant,
10609	// but we use a bit of a hack here for speed; this is a relatively
10610	// hot path, and isNullPointerConstant is slow.
10611	bool LHSNull = isa<GNUNullExpr>(Val: LHS.get()->IgnoreParenImpCasts());
10612	bool RHSNull = isa<GNUNullExpr>(Val: RHS.get()->IgnoreParenImpCasts());
10613
10614	QualType NonNullType = LHSNull ? RHS.get()->getType() : LHS.get()->getType();
10615
10616	// Avoid analyzing cases where the result will either be invalid (and
10617	// diagnosed as such) or entirely valid and not something to warn about.
10618	if ((!LHSNull && !RHSNull) || NonNullType->isBlockPointerType() ||
10619	NonNullType->isMemberPointerType() || NonNullType->isFunctionType())
10620	return;
10621
10622	// Comparison operations would not make sense with a null pointer no matter
10623	// what the other expression is.
10624	if (!IsCompare) {
10625	S.Diag(Loc, DiagID: diag::warn_null_in_arithmetic_operation)
10626	<< (LHSNull ? LHS.get()->getSourceRange() : SourceRange())
10627	<< (RHSNull ? RHS.get()->getSourceRange() : SourceRange());
10628	return;
10629	}
10630
10631	// The rest of the operations only make sense with a null pointer
10632	// if the other expression is a pointer.
10633	if (LHSNull == RHSNull || NonNullType->isAnyPointerType() ||
10634	NonNullType->canDecayToPointerType())
10635	return;
10636
10637	S.Diag(Loc, DiagID: diag::warn_null_in_comparison_operation)
10638	<< LHSNull /* LHS is NULL */ << NonNullType
10639	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
10640	}
10641
10642	static void DetectPrecisionLossInComplexDivision(Sema &S, QualType DivisorTy,
10643	SourceLocation OpLoc) {
10644	// If the divisor is real, then this is real/real or complex/real division.
10645	// Either way there can be no precision loss.
10646	auto *CT = DivisorTy->getAs<ComplexType>();
10647	if (!CT)
10648	return;
10649
10650	QualType ElementType = CT->getElementType();
10651	bool IsComplexRangePromoted = S.getLangOpts().getComplexRange() ==
10652	LangOptions::ComplexRangeKind::CX_Promoted;
10653	if (!ElementType->isFloatingType() || !IsComplexRangePromoted)
10654	return;
10655
10656	ASTContext &Ctx = S.getASTContext();
10657	QualType HigherElementType = Ctx.GetHigherPrecisionFPType(ElementType);
10658	const llvm::fltSemantics &ElementTypeSemantics =
10659	Ctx.getFloatTypeSemantics(T: ElementType);
10660	const llvm::fltSemantics &HigherElementTypeSemantics =
10661	Ctx.getFloatTypeSemantics(T: HigherElementType);
10662
10663	if ((llvm::APFloat::semanticsMaxExponent(ElementTypeSemantics) * 2 + 1 >
10664	llvm::APFloat::semanticsMaxExponent(HigherElementTypeSemantics)) ||
10665	(HigherElementType == Ctx.LongDoubleTy &&
10666	!Ctx.getTargetInfo().hasLongDoubleType())) {
10667	// Retain the location of the first use of higher precision type.
10668	if (!S.LocationOfExcessPrecisionNotSatisfied.isValid())
10669	S.LocationOfExcessPrecisionNotSatisfied = OpLoc;
10670	for (auto &[Type, Num] : S.ExcessPrecisionNotSatisfied) {
10671	if (Type == HigherElementType) {
10672	Num++;
10673	return;
10674	}
10675	}
10676	S.ExcessPrecisionNotSatisfied.push_back(x: std::make_pair(
10677	x&: HigherElementType, y: S.ExcessPrecisionNotSatisfied.size()));
10678	}
10679	}
10680
10681	static void DiagnoseDivisionSizeofPointerOrArray(Sema &S, Expr *LHS, Expr *RHS,
10682	SourceLocation Loc) {
10683	const auto *LUE = dyn_cast<UnaryExprOrTypeTraitExpr>(Val: LHS);
10684	const auto *RUE = dyn_cast<UnaryExprOrTypeTraitExpr>(Val: RHS);
10685	if (!LUE || !RUE)
10686	return;
10687	if (LUE->getKind() != UETT_SizeOf || LUE->isArgumentType() ||
10688	RUE->getKind() != UETT_SizeOf)
10689	return;
10690
10691	const Expr *LHSArg = LUE->getArgumentExpr()->IgnoreParens();
10692	QualType LHSTy = LHSArg->getType();
10693	QualType RHSTy;
10694
10695	if (RUE->isArgumentType())
10696	RHSTy = RUE->getArgumentType().getNonReferenceType();
10697	else
10698	RHSTy = RUE->getArgumentExpr()->IgnoreParens()->getType();
10699
10700	if (LHSTy->isPointerType() && !RHSTy->isPointerType()) {
10701	if (!S.Context.hasSameUnqualifiedType(T1: LHSTy->getPointeeType(), T2: RHSTy))
10702	return;
10703
10704	S.Diag(Loc, DiagID: diag::warn_division_sizeof_ptr) << LHS << LHS->getSourceRange();
10705	if (const auto *DRE = dyn_cast<DeclRefExpr>(Val: LHSArg)) {
10706	if (const ValueDecl *LHSArgDecl = DRE->getDecl())
10707	S.Diag(Loc: LHSArgDecl->getLocation(), DiagID: diag::note_pointer_declared_here)
10708	<< LHSArgDecl;
10709	}
10710	} else if (const auto *ArrayTy = S.Context.getAsArrayType(T: LHSTy)) {
10711	QualType ArrayElemTy = ArrayTy->getElementType();
10712	if (ArrayElemTy != S.Context.getBaseElementType(VAT: ArrayTy) ||
10713	ArrayElemTy->isDependentType() || RHSTy->isDependentType() ||
10714	RHSTy->isReferenceType() || ArrayElemTy->isCharType() ||
10715	S.Context.getTypeSize(T: ArrayElemTy) == S.Context.getTypeSize(T: RHSTy))
10716	return;
10717	S.Diag(Loc, DiagID: diag::warn_division_sizeof_array)
10718	<< LHSArg->getSourceRange() << ArrayElemTy << RHSTy;
10719	if (const auto *DRE = dyn_cast<DeclRefExpr>(Val: LHSArg)) {
10720	if (const ValueDecl *LHSArgDecl = DRE->getDecl())
10721	S.Diag(Loc: LHSArgDecl->getLocation(), DiagID: diag::note_array_declared_here)
10722	<< LHSArgDecl;
10723	}
10724
10725	S.Diag(Loc, DiagID: diag::note_precedence_silence) << RHS;
10726	}
10727	}
10728
10729	static void DiagnoseBadDivideOrRemainderValues(Sema& S, ExprResult &LHS,
10730	ExprResult &RHS,
10731	SourceLocation Loc, bool IsDiv) {
10732	// Check for division/remainder by zero.
10733	Expr::EvalResult RHSValue;
10734	if (!RHS.get()->isValueDependent() &&
10735	RHS.get()->EvaluateAsInt(Result&: RHSValue, Ctx: S.Context) &&
10736	RHSValue.Val.getInt() == 0)
10737	S.DiagRuntimeBehavior(Loc, Statement: RHS.get(),
10738	PD: S.PDiag(DiagID: diag::warn_remainder_division_by_zero)
10739	<< IsDiv << RHS.get()->getSourceRange());
10740	}
10741
10742	QualType Sema::CheckMultiplyDivideOperands(ExprResult &LHS, ExprResult &RHS,
10743	SourceLocation Loc,
10744	bool IsCompAssign, bool IsDiv) {
10745	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
10746
10747	QualType LHSTy = LHS.get()->getType();
10748	QualType RHSTy = RHS.get()->getType();
10749	if (LHSTy->isVectorType() || RHSTy->isVectorType())
10750	return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
10751	/*AllowBothBool*/ getLangOpts().AltiVec,
10752	/*AllowBoolConversions*/ false,
10753	/*AllowBooleanOperation*/ AllowBoolOperation: false,
10754	/*ReportInvalid*/ true);
10755	if (LHSTy->isSveVLSBuiltinType() || RHSTy->isSveVLSBuiltinType())
10756	return CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign,
10757	OperationKind: ArithConvKind::Arithmetic);
10758	if (!IsDiv &&
10759	(LHSTy->isConstantMatrixType() || RHSTy->isConstantMatrixType()))
10760	return CheckMatrixMultiplyOperands(LHS, RHS, Loc, IsCompAssign);
10761	// For division, only matrix-by-scalar is supported. Other combinations with
10762	// matrix types are invalid.
10763	if (IsDiv && LHSTy->isConstantMatrixType() && RHSTy->isArithmeticType())
10764	return CheckMatrixElementwiseOperands(LHS, RHS, Loc, IsCompAssign);
10765
10766	QualType compType = UsualArithmeticConversions(
10767	LHS, RHS, Loc,
10768	ACK: IsCompAssign ? ArithConvKind::CompAssign : ArithConvKind::Arithmetic);
10769	if (LHS.isInvalid() || RHS.isInvalid())
10770	return QualType();
10771
10772
10773	if (compType.isNull() || !compType->isArithmeticType())
10774	return InvalidOperands(Loc, LHS, RHS);
10775	if (IsDiv) {
10776	DetectPrecisionLossInComplexDivision(S&: *this, DivisorTy: RHS.get()->getType(), OpLoc: Loc);
10777	DiagnoseBadDivideOrRemainderValues(S&: *this, LHS, RHS, Loc, IsDiv);
10778	DiagnoseDivisionSizeofPointerOrArray(S&: *this, LHS: LHS.get(), RHS: RHS.get(), Loc);
10779	}
10780	return compType;
10781	}
10782
10783	QualType Sema::CheckRemainderOperands(
10784	ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) {
10785	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
10786
10787	// Note: This check is here to simplify the double exclusions of
10788	// scalar and vector HLSL checks. No getLangOpts().HLSL
10789	// is needed since all languages exlcude doubles.
10790	if (LHS.get()->getType()->isDoubleType() ||
10791	RHS.get()->getType()->isDoubleType() ||
10792	(LHS.get()->getType()->isVectorType() && LHS.get()
10793	->getType()
10794	->getAs<VectorType>()
10795	->getElementType()
10796	->isDoubleType()) ||
10797	(RHS.get()->getType()->isVectorType() && RHS.get()
10798	->getType()
10799	->getAs<VectorType>()
10800	->getElementType()
10801	->isDoubleType()))
10802	return InvalidOperands(Loc, LHS, RHS);
10803
10804	if (LHS.get()->getType()->isVectorType() ||
10805	RHS.get()->getType()->isVectorType()) {
10806	if ((LHS.get()->getType()->hasIntegerRepresentation() &&
10807	RHS.get()->getType()->hasIntegerRepresentation()) ||
10808	(getLangOpts().HLSL &&
10809	(LHS.get()->getType()->hasFloatingRepresentation() ||
10810	RHS.get()->getType()->hasFloatingRepresentation())))
10811	return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
10812	/*AllowBothBool*/ getLangOpts().AltiVec,
10813	/*AllowBoolConversions*/ false,
10814	/*AllowBooleanOperation*/ AllowBoolOperation: false,
10815	/*ReportInvalid*/ true);
10816	return InvalidOperands(Loc, LHS, RHS);
10817	}
10818
10819	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
10820	RHS.get()->getType()->isSveVLSBuiltinType()) {
10821	if (LHS.get()->getType()->hasIntegerRepresentation() &&
10822	RHS.get()->getType()->hasIntegerRepresentation())
10823	return CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign,
10824	OperationKind: ArithConvKind::Arithmetic);
10825
10826	return InvalidOperands(Loc, LHS, RHS);
10827	}
10828
10829	QualType compType = UsualArithmeticConversions(
10830	LHS, RHS, Loc,
10831	ACK: IsCompAssign ? ArithConvKind::CompAssign : ArithConvKind::Arithmetic);
10832	if (LHS.isInvalid() || RHS.isInvalid())
10833	return QualType();
10834
10835	if (compType.isNull() ||
10836	(!compType->isIntegerType() &&
10837	!(getLangOpts().HLSL && compType->isFloatingType())))
10838	return InvalidOperands(Loc, LHS, RHS);
10839	DiagnoseBadDivideOrRemainderValues(S&: *this, LHS, RHS, Loc, IsDiv: false /* IsDiv */);
10840	return compType;
10841	}
10842
10843	/// Diagnose invalid arithmetic on two void pointers.
10844	static void diagnoseArithmeticOnTwoVoidPointers(Sema &S, SourceLocation Loc,
10845	Expr *LHSExpr, Expr *RHSExpr) {
10846	S.Diag(Loc, DiagID: S.getLangOpts().CPlusPlus
10847	? diag::err_typecheck_pointer_arith_void_type
10848	: diag::ext_gnu_void_ptr)
10849	<< 1 /* two pointers */ << LHSExpr->getSourceRange()
10850	<< RHSExpr->getSourceRange();
10851	}
10852
10853	/// Diagnose invalid arithmetic on a void pointer.
10854	static void diagnoseArithmeticOnVoidPointer(Sema &S, SourceLocation Loc,
10855	Expr *Pointer) {
10856	S.Diag(Loc, DiagID: S.getLangOpts().CPlusPlus
10857	? diag::err_typecheck_pointer_arith_void_type
10858	: diag::ext_gnu_void_ptr)
10859	<< 0 /* one pointer */ << Pointer->getSourceRange();
10860	}
10861
10862	/// Diagnose invalid arithmetic on a null pointer.
10863	///
10864	/// If \p IsGNUIdiom is true, the operation is using the 'p = (i8*)nullptr + n'
10865	/// idiom, which we recognize as a GNU extension.
10866	///
10867	static void diagnoseArithmeticOnNullPointer(Sema &S, SourceLocation Loc,
10868	Expr *Pointer, bool IsGNUIdiom) {
10869	if (IsGNUIdiom)
10870	S.Diag(Loc, DiagID: diag::warn_gnu_null_ptr_arith)
10871	<< Pointer->getSourceRange();
10872	else
10873	S.Diag(Loc, DiagID: diag::warn_pointer_arith_null_ptr)
10874	<< S.getLangOpts().CPlusPlus << Pointer->getSourceRange();
10875	}
10876
10877	/// Diagnose invalid subraction on a null pointer.
10878	///
10879	static void diagnoseSubtractionOnNullPointer(Sema &S, SourceLocation Loc,
10880	Expr *Pointer, bool BothNull) {
10881	// Null - null is valid in C++ [expr.add]p7
10882	if (BothNull && S.getLangOpts().CPlusPlus)
10883	return;
10884
10885	// Is this s a macro from a system header?
10886	if (S.Diags.getSuppressSystemWarnings() && S.SourceMgr.isInSystemMacro(loc: Loc))
10887	return;
10888
10889	S.DiagRuntimeBehavior(Loc, Statement: Pointer,
10890	PD: S.PDiag(DiagID: diag::warn_pointer_sub_null_ptr)
10891	<< S.getLangOpts().CPlusPlus
10892	<< Pointer->getSourceRange());
10893	}
10894
10895	/// Diagnose invalid arithmetic on two function pointers.
10896	static void diagnoseArithmeticOnTwoFunctionPointers(Sema &S, SourceLocation Loc,
10897	Expr *LHS, Expr *RHS) {
10898	assert(LHS->getType()->isAnyPointerType());
10899	assert(RHS->getType()->isAnyPointerType());
10900	S.Diag(Loc, DiagID: S.getLangOpts().CPlusPlus
10901	? diag::err_typecheck_pointer_arith_function_type
10902	: diag::ext_gnu_ptr_func_arith)
10903	<< 1 /* two pointers */ << LHS->getType()->getPointeeType()
10904	// We only show the second type if it differs from the first.
10905	<< (unsigned)!S.Context.hasSameUnqualifiedType(T1: LHS->getType(),
10906	T2: RHS->getType())
10907	<< RHS->getType()->getPointeeType()
10908	<< LHS->getSourceRange() << RHS->getSourceRange();
10909	}
10910
10911	/// Diagnose invalid arithmetic on a function pointer.
10912	static void diagnoseArithmeticOnFunctionPointer(Sema &S, SourceLocation Loc,
10913	Expr *Pointer) {
10914	assert(Pointer->getType()->isAnyPointerType());
10915	S.Diag(Loc, DiagID: S.getLangOpts().CPlusPlus
10916	? diag::err_typecheck_pointer_arith_function_type
10917	: diag::ext_gnu_ptr_func_arith)
10918	<< 0 /* one pointer */ << Pointer->getType()->getPointeeType()
10919	<< 0 /* one pointer, so only one type */
10920	<< Pointer->getSourceRange();
10921	}
10922
10923	/// Emit error if Operand is incomplete pointer type
10924	///
10925	/// \returns True if pointer has incomplete type
10926	static bool checkArithmeticIncompletePointerType(Sema &S, SourceLocation Loc,
10927	Expr *Operand) {
10928	QualType ResType = Operand->getType();
10929	if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
10930	ResType = ResAtomicType->getValueType();
10931
10932	assert(ResType->isAnyPointerType());
10933	QualType PointeeTy = ResType->getPointeeType();
10934	return S.RequireCompleteSizedType(
10935	Loc, T: PointeeTy,
10936	DiagID: diag::err_typecheck_arithmetic_incomplete_or_sizeless_type,
10937	Args: Operand->getSourceRange());
10938	}
10939
10940	/// Check the validity of an arithmetic pointer operand.
10941	///
10942	/// If the operand has pointer type, this code will check for pointer types
10943	/// which are invalid in arithmetic operations. These will be diagnosed
10944	/// appropriately, including whether or not the use is supported as an
10945	/// extension.
10946	///
10947	/// \returns True when the operand is valid to use (even if as an extension).
10948	static bool checkArithmeticOpPointerOperand(Sema &S, SourceLocation Loc,
10949	Expr *Operand) {
10950	QualType ResType = Operand->getType();
10951	if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
10952	ResType = ResAtomicType->getValueType();
10953
10954	if (!ResType->isAnyPointerType()) return true;
10955
10956	QualType PointeeTy = ResType->getPointeeType();
10957	if (PointeeTy->isVoidType()) {
10958	diagnoseArithmeticOnVoidPointer(S, Loc, Pointer: Operand);
10959	return !S.getLangOpts().CPlusPlus;
10960	}
10961	if (PointeeTy->isFunctionType()) {
10962	diagnoseArithmeticOnFunctionPointer(S, Loc, Pointer: Operand);
10963	return !S.getLangOpts().CPlusPlus;
10964	}
10965
10966	if (checkArithmeticIncompletePointerType(S, Loc, Operand)) return false;
10967
10968	return true;
10969	}
10970
10971	/// Check the validity of a binary arithmetic operation w.r.t. pointer
10972	/// operands.
10973	///
10974	/// This routine will diagnose any invalid arithmetic on pointer operands much
10975	/// like \see checkArithmeticOpPointerOperand. However, it has special logic
10976	/// for emitting a single diagnostic even for operations where both LHS and RHS
10977	/// are (potentially problematic) pointers.
10978	///
10979	/// \returns True when the operand is valid to use (even if as an extension).
10980	static bool checkArithmeticBinOpPointerOperands(Sema &S, SourceLocation Loc,
10981	Expr *LHSExpr, Expr *RHSExpr) {
10982	bool isLHSPointer = LHSExpr->getType()->isAnyPointerType();
10983	bool isRHSPointer = RHSExpr->getType()->isAnyPointerType();
10984	if (!isLHSPointer && !isRHSPointer) return true;
10985
10986	QualType LHSPointeeTy, RHSPointeeTy;
10987	if (isLHSPointer) LHSPointeeTy = LHSExpr->getType()->getPointeeType();
10988	if (isRHSPointer) RHSPointeeTy = RHSExpr->getType()->getPointeeType();
10989
10990	// if both are pointers check if operation is valid wrt address spaces
10991	if (isLHSPointer && isRHSPointer) {
10992	if (!LHSPointeeTy.isAddressSpaceOverlapping(T: RHSPointeeTy,
10993	Ctx: S.getASTContext())) {
10994	S.Diag(Loc,
10995	DiagID: diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
10996	<< LHSExpr->getType() << RHSExpr->getType() << 1 /*arithmetic op*/
10997	<< LHSExpr->getSourceRange() << RHSExpr->getSourceRange();
10998	return false;
10999	}
11000	}
11001
11002	// Check for arithmetic on pointers to incomplete types.
11003	bool isLHSVoidPtr = isLHSPointer && LHSPointeeTy->isVoidType();
11004	bool isRHSVoidPtr = isRHSPointer && RHSPointeeTy->isVoidType();
11005	if (isLHSVoidPtr || isRHSVoidPtr) {
11006	if (!isRHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, Pointer: LHSExpr);
11007	else if (!isLHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, Pointer: RHSExpr);
11008	else diagnoseArithmeticOnTwoVoidPointers(S, Loc, LHSExpr, RHSExpr);
11009
11010	return !S.getLangOpts().CPlusPlus;
11011	}
11012
11013	bool isLHSFuncPtr = isLHSPointer && LHSPointeeTy->isFunctionType();
11014	bool isRHSFuncPtr = isRHSPointer && RHSPointeeTy->isFunctionType();
11015	if (isLHSFuncPtr || isRHSFuncPtr) {
11016	if (!isRHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, Pointer: LHSExpr);
11017	else if (!isLHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc,
11018	Pointer: RHSExpr);
11019	else diagnoseArithmeticOnTwoFunctionPointers(S, Loc, LHS: LHSExpr, RHS: RHSExpr);
11020
11021	return !S.getLangOpts().CPlusPlus;
11022	}
11023
11024	if (isLHSPointer && checkArithmeticIncompletePointerType(S, Loc, Operand: LHSExpr))
11025	return false;
11026	if (isRHSPointer && checkArithmeticIncompletePointerType(S, Loc, Operand: RHSExpr))
11027	return false;
11028
11029	return true;
11030	}
11031
11032	/// diagnoseStringPlusInt - Emit a warning when adding an integer to a string
11033	/// literal.
11034	static void diagnoseStringPlusInt(Sema &Self, SourceLocation OpLoc,
11035	Expr *LHSExpr, Expr *RHSExpr) {
11036	StringLiteral* StrExpr = dyn_cast<StringLiteral>(Val: LHSExpr->IgnoreImpCasts());
11037	Expr* IndexExpr = RHSExpr;
11038	if (!StrExpr) {
11039	StrExpr = dyn_cast<StringLiteral>(Val: RHSExpr->IgnoreImpCasts());
11040	IndexExpr = LHSExpr;
11041	}
11042
11043	bool IsStringPlusInt = StrExpr &&
11044	IndexExpr->getType()->isIntegralOrUnscopedEnumerationType();
11045	if (!IsStringPlusInt || IndexExpr->isValueDependent())
11046	return;
11047
11048	SourceRange DiagRange(LHSExpr->getBeginLoc(), RHSExpr->getEndLoc());
11049	Self.Diag(Loc: OpLoc, DiagID: diag::warn_string_plus_int)
11050	<< DiagRange << IndexExpr->IgnoreImpCasts()->getType();
11051
11052	// Only print a fixit for "str" + int, not for int + "str".
11053	if (IndexExpr == RHSExpr) {
11054	SourceLocation EndLoc = Self.getLocForEndOfToken(Loc: RHSExpr->getEndLoc());
11055	Self.Diag(Loc: OpLoc, DiagID: diag::note_string_plus_scalar_silence)
11056	<< FixItHint::CreateInsertion(InsertionLoc: LHSExpr->getBeginLoc(), Code: "&")
11057	<< FixItHint::CreateReplacement(RemoveRange: SourceRange(OpLoc), Code: "[")
11058	<< FixItHint::CreateInsertion(InsertionLoc: EndLoc, Code: "]");
11059	} else
11060	Self.Diag(Loc: OpLoc, DiagID: diag::note_string_plus_scalar_silence);
11061	}
11062
11063	/// Emit a warning when adding a char literal to a string.
11064	static void diagnoseStringPlusChar(Sema &Self, SourceLocation OpLoc,
11065	Expr *LHSExpr, Expr *RHSExpr) {
11066	const Expr *StringRefExpr = LHSExpr;
11067	const CharacterLiteral *CharExpr =
11068	dyn_cast<CharacterLiteral>(Val: RHSExpr->IgnoreImpCasts());
11069
11070	if (!CharExpr) {
11071	CharExpr = dyn_cast<CharacterLiteral>(Val: LHSExpr->IgnoreImpCasts());
11072	StringRefExpr = RHSExpr;
11073	}
11074
11075	if (!CharExpr || !StringRefExpr)
11076	return;
11077
11078	const QualType StringType = StringRefExpr->getType();
11079
11080	// Return if not a PointerType.
11081	if (!StringType->isAnyPointerType())
11082	return;
11083
11084	// Return if not a CharacterType.
11085	if (!StringType->getPointeeType()->isAnyCharacterType())
11086	return;
11087
11088	ASTContext &Ctx = Self.getASTContext();
11089	SourceRange DiagRange(LHSExpr->getBeginLoc(), RHSExpr->getEndLoc());
11090
11091	const QualType CharType = CharExpr->getType();
11092	if (!CharType->isAnyCharacterType() &&
11093	CharType->isIntegerType() &&
11094	llvm::isUIntN(N: Ctx.getCharWidth(), x: CharExpr->getValue())) {
11095	Self.Diag(Loc: OpLoc, DiagID: diag::warn_string_plus_char)
11096	<< DiagRange << Ctx.CharTy;
11097	} else {
11098	Self.Diag(Loc: OpLoc, DiagID: diag::warn_string_plus_char)
11099	<< DiagRange << CharExpr->getType();
11100	}
11101
11102	// Only print a fixit for str + char, not for char + str.
11103	if (isa<CharacterLiteral>(Val: RHSExpr->IgnoreImpCasts())) {
11104	SourceLocation EndLoc = Self.getLocForEndOfToken(Loc: RHSExpr->getEndLoc());
11105	Self.Diag(Loc: OpLoc, DiagID: diag::note_string_plus_scalar_silence)
11106	<< FixItHint::CreateInsertion(InsertionLoc: LHSExpr->getBeginLoc(), Code: "&")
11107	<< FixItHint::CreateReplacement(RemoveRange: SourceRange(OpLoc), Code: "[")
11108	<< FixItHint::CreateInsertion(InsertionLoc: EndLoc, Code: "]");
11109	} else {
11110	Self.Diag(Loc: OpLoc, DiagID: diag::note_string_plus_scalar_silence);
11111	}
11112	}
11113
11114	/// Emit error when two pointers are incompatible.
11115	static void diagnosePointerIncompatibility(Sema &S, SourceLocation Loc,
11116	Expr *LHSExpr, Expr *RHSExpr) {
11117	assert(LHSExpr->getType()->isAnyPointerType());
11118	assert(RHSExpr->getType()->isAnyPointerType());
11119	S.Diag(Loc, DiagID: diag::err_typecheck_sub_ptr_compatible)
11120	<< LHSExpr->getType() << RHSExpr->getType() << LHSExpr->getSourceRange()
11121	<< RHSExpr->getSourceRange();
11122	}
11123
11124	// C99 6.5.6
11125	QualType Sema::CheckAdditionOperands(ExprResult &LHS, ExprResult &RHS,
11126	SourceLocation Loc, BinaryOperatorKind Opc,
11127	QualType* CompLHSTy) {
11128	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
11129
11130	if (LHS.get()->getType()->isVectorType() ||
11131	RHS.get()->getType()->isVectorType()) {
11132	QualType compType =
11133	CheckVectorOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy,
11134	/*AllowBothBool*/ getLangOpts().AltiVec,
11135	/*AllowBoolConversions*/ getLangOpts().ZVector,
11136	/*AllowBooleanOperation*/ AllowBoolOperation: false,
11137	/*ReportInvalid*/ true);
11138	if (CompLHSTy) *CompLHSTy = compType;
11139	return compType;
11140	}
11141
11142	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
11143	RHS.get()->getType()->isSveVLSBuiltinType()) {
11144	QualType compType = CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy,
11145	OperationKind: ArithConvKind::Arithmetic);
11146	if (CompLHSTy)
11147	*CompLHSTy = compType;
11148	return compType;
11149	}
11150
11151	if (LHS.get()->getType()->isConstantMatrixType() ||
11152	RHS.get()->getType()->isConstantMatrixType()) {
11153	QualType compType =
11154	CheckMatrixElementwiseOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy);
11155	if (CompLHSTy)
11156	*CompLHSTy = compType;
11157	return compType;
11158	}
11159
11160	QualType compType = UsualArithmeticConversions(
11161	LHS, RHS, Loc,
11162	ACK: CompLHSTy ? ArithConvKind::CompAssign : ArithConvKind::Arithmetic);
11163	if (LHS.isInvalid() || RHS.isInvalid())
11164	return QualType();
11165
11166	// Diagnose "string literal" '+' int and string '+' "char literal".
11167	if (Opc == BO_Add) {
11168	diagnoseStringPlusInt(Self&: *this, OpLoc: Loc, LHSExpr: LHS.get(), RHSExpr: RHS.get());
11169	diagnoseStringPlusChar(Self&: *this, OpLoc: Loc, LHSExpr: LHS.get(), RHSExpr: RHS.get());
11170	}
11171
11172	// handle the common case first (both operands are arithmetic).
11173	if (!compType.isNull() && compType->isArithmeticType()) {
11174	if (CompLHSTy) *CompLHSTy = compType;
11175	return compType;
11176	}
11177
11178	// Type-checking. Ultimately the pointer's going to be in PExp;
11179	// note that we bias towards the LHS being the pointer.
11180	Expr *PExp = LHS.get(), *IExp = RHS.get();
11181
11182	bool isObjCPointer;
11183	if (PExp->getType()->isPointerType()) {
11184	isObjCPointer = false;
11185	} else if (PExp->getType()->isObjCObjectPointerType()) {
11186	isObjCPointer = true;
11187	} else {
11188	std::swap(a&: PExp, b&: IExp);
11189	if (PExp->getType()->isPointerType()) {
11190	isObjCPointer = false;
11191	} else if (PExp->getType()->isObjCObjectPointerType()) {
11192	isObjCPointer = true;
11193	} else {
11194	return InvalidOperands(Loc, LHS, RHS);
11195	}
11196	}
11197	assert(PExp->getType()->isAnyPointerType());
11198
11199	if (!IExp->getType()->isIntegerType())
11200	return InvalidOperands(Loc, LHS, RHS);
11201
11202	// Adding to a null pointer results in undefined behavior.
11203	if (PExp->IgnoreParenCasts()->isNullPointerConstant(
11204	Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNotNull)) {
11205	// In C++ adding zero to a null pointer is defined.
11206	Expr::EvalResult KnownVal;
11207	if (!getLangOpts().CPlusPlus ||
11208	(!IExp->isValueDependent() &&
11209	(!IExp->EvaluateAsInt(Result&: KnownVal, Ctx: Context) ||
11210	KnownVal.Val.getInt() != 0))) {
11211	// Check the conditions to see if this is the 'p = nullptr + n' idiom.
11212	bool IsGNUIdiom = BinaryOperator::isNullPointerArithmeticExtension(
11213	Ctx&: Context, Opc: BO_Add, LHS: PExp, RHS: IExp);
11214	diagnoseArithmeticOnNullPointer(S&: *this, Loc, Pointer: PExp, IsGNUIdiom);
11215	}
11216	}
11217
11218	if (!checkArithmeticOpPointerOperand(S&: *this, Loc, Operand: PExp))
11219	return QualType();
11220
11221	if (isObjCPointer && checkArithmeticOnObjCPointer(S&: *this, opLoc: Loc, op: PExp))
11222	return QualType();
11223
11224	// Arithmetic on label addresses is normally allowed, except when we add
11225	// a ptrauth signature to the addresses.
11226	if (isa<AddrLabelExpr>(Val: PExp) && getLangOpts().PointerAuthIndirectGotos) {
11227	Diag(Loc, DiagID: diag::err_ptrauth_indirect_goto_addrlabel_arithmetic)
11228	<< /*addition*/ 1;
11229	return QualType();
11230	}
11231
11232	// Check array bounds for pointer arithemtic
11233	CheckArrayAccess(BaseExpr: PExp, IndexExpr: IExp);
11234
11235	if (CompLHSTy) {
11236	QualType LHSTy = Context.isPromotableBitField(E: LHS.get());
11237	if (LHSTy.isNull()) {
11238	LHSTy = LHS.get()->getType();
11239	if (Context.isPromotableIntegerType(T: LHSTy))
11240	LHSTy = Context.getPromotedIntegerType(PromotableType: LHSTy);
11241	}
11242	*CompLHSTy = LHSTy;
11243	}
11244
11245	return PExp->getType();
11246	}
11247
11248	// C99 6.5.6
11249	QualType Sema::CheckSubtractionOperands(ExprResult &LHS, ExprResult &RHS,
11250	SourceLocation Loc,
11251	QualType* CompLHSTy) {
11252	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
11253
11254	if (LHS.get()->getType()->isVectorType() ||
11255	RHS.get()->getType()->isVectorType()) {
11256	QualType compType =
11257	CheckVectorOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy,
11258	/*AllowBothBool*/ getLangOpts().AltiVec,
11259	/*AllowBoolConversions*/ getLangOpts().ZVector,
11260	/*AllowBooleanOperation*/ AllowBoolOperation: false,
11261	/*ReportInvalid*/ true);
11262	if (CompLHSTy) *CompLHSTy = compType;
11263	return compType;
11264	}
11265
11266	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
11267	RHS.get()->getType()->isSveVLSBuiltinType()) {
11268	QualType compType = CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy,
11269	OperationKind: ArithConvKind::Arithmetic);
11270	if (CompLHSTy)
11271	*CompLHSTy = compType;
11272	return compType;
11273	}
11274
11275	if (LHS.get()->getType()->isConstantMatrixType() ||
11276	RHS.get()->getType()->isConstantMatrixType()) {
11277	QualType compType =
11278	CheckMatrixElementwiseOperands(LHS, RHS, Loc, IsCompAssign: CompLHSTy);
11279	if (CompLHSTy)
11280	*CompLHSTy = compType;
11281	return compType;
11282	}
11283
11284	QualType compType = UsualArithmeticConversions(
11285	LHS, RHS, Loc,
11286	ACK: CompLHSTy ? ArithConvKind::CompAssign : ArithConvKind::Arithmetic);
11287	if (LHS.isInvalid() || RHS.isInvalid())
11288	return QualType();
11289
11290	// Enforce type constraints: C99 6.5.6p3.
11291
11292	// Handle the common case first (both operands are arithmetic).
11293	if (!compType.isNull() && compType->isArithmeticType()) {
11294	if (CompLHSTy) *CompLHSTy = compType;
11295	return compType;
11296	}
11297
11298	// Either ptr - int or ptr - ptr.
11299	if (LHS.get()->getType()->isAnyPointerType()) {
11300	QualType lpointee = LHS.get()->getType()->getPointeeType();
11301
11302	// Diagnose bad cases where we step over interface counts.
11303	if (LHS.get()->getType()->isObjCObjectPointerType() &&
11304	checkArithmeticOnObjCPointer(S&: *this, opLoc: Loc, op: LHS.get()))
11305	return QualType();
11306
11307	// Arithmetic on label addresses is normally allowed, except when we add
11308	// a ptrauth signature to the addresses.
11309	if (isa<AddrLabelExpr>(Val: LHS.get()) &&
11310	getLangOpts().PointerAuthIndirectGotos) {
11311	Diag(Loc, DiagID: diag::err_ptrauth_indirect_goto_addrlabel_arithmetic)
11312	<< /*subtraction*/ 0;
11313	return QualType();
11314	}
11315
11316	// The result type of a pointer-int computation is the pointer type.
11317	if (RHS.get()->getType()->isIntegerType()) {
11318	// Subtracting from a null pointer should produce a warning.
11319	// The last argument to the diagnose call says this doesn't match the
11320	// GNU int-to-pointer idiom.
11321	if (LHS.get()->IgnoreParenCasts()->isNullPointerConstant(Ctx&: Context,
11322	NPC: Expr::NPC_ValueDependentIsNotNull)) {
11323	// In C++ adding zero to a null pointer is defined.
11324	Expr::EvalResult KnownVal;
11325	if (!getLangOpts().CPlusPlus ||
11326	(!RHS.get()->isValueDependent() &&
11327	(!RHS.get()->EvaluateAsInt(Result&: KnownVal, Ctx: Context) ||
11328	KnownVal.Val.getInt() != 0))) {
11329	diagnoseArithmeticOnNullPointer(S&: *this, Loc, Pointer: LHS.get(), IsGNUIdiom: false);
11330	}
11331	}
11332
11333	if (!checkArithmeticOpPointerOperand(S&: *this, Loc, Operand: LHS.get()))
11334	return QualType();
11335
11336	// Check array bounds for pointer arithemtic
11337	CheckArrayAccess(BaseExpr: LHS.get(), IndexExpr: RHS.get(), /*ArraySubscriptExpr*/ASE: nullptr,
11338	/*AllowOnePastEnd*/true, /*IndexNegated*/true);
11339
11340	if (CompLHSTy) *CompLHSTy = LHS.get()->getType();
11341	return LHS.get()->getType();
11342	}
11343
11344	// Handle pointer-pointer subtractions.
11345	if (const PointerType *RHSPTy
11346	= RHS.get()->getType()->getAs<PointerType>()) {
11347	QualType rpointee = RHSPTy->getPointeeType();
11348
11349	if (getLangOpts().CPlusPlus) {
11350	// Pointee types must be the same: C++ [expr.add]
11351	if (!Context.hasSameUnqualifiedType(T1: lpointee, T2: rpointee)) {
11352	diagnosePointerIncompatibility(S&: *this, Loc, LHSExpr: LHS.get(), RHSExpr: RHS.get());
11353	}
11354	} else {
11355	// Pointee types must be compatible C99 6.5.6p3
11356	if (!Context.typesAreCompatible(
11357	T1: Context.getCanonicalType(T: lpointee).getUnqualifiedType(),
11358	T2: Context.getCanonicalType(T: rpointee).getUnqualifiedType())) {
11359	diagnosePointerIncompatibility(S&: *this, Loc, LHSExpr: LHS.get(), RHSExpr: RHS.get());
11360	return QualType();
11361	}
11362	}
11363
11364	if (!checkArithmeticBinOpPointerOperands(S&: *this, Loc,
11365	LHSExpr: LHS.get(), RHSExpr: RHS.get()))
11366	return QualType();
11367
11368	bool LHSIsNullPtr = LHS.get()->IgnoreParenCasts()->isNullPointerConstant(
11369	Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNotNull);
11370	bool RHSIsNullPtr = RHS.get()->IgnoreParenCasts()->isNullPointerConstant(
11371	Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNotNull);
11372
11373	// Subtracting nullptr or from nullptr is suspect
11374	if (LHSIsNullPtr)
11375	diagnoseSubtractionOnNullPointer(S&: *this, Loc, Pointer: LHS.get(), BothNull: RHSIsNullPtr);
11376	if (RHSIsNullPtr)
11377	diagnoseSubtractionOnNullPointer(S&: *this, Loc, Pointer: RHS.get(), BothNull: LHSIsNullPtr);
11378
11379	// The pointee type may have zero size. As an extension, a structure or
11380	// union may have zero size or an array may have zero length. In this
11381	// case subtraction does not make sense.
11382	if (!rpointee->isVoidType() && !rpointee->isFunctionType()) {
11383	CharUnits ElementSize = Context.getTypeSizeInChars(T: rpointee);
11384	if (ElementSize.isZero()) {
11385	Diag(Loc,DiagID: diag::warn_sub_ptr_zero_size_types)
11386	<< rpointee.getUnqualifiedType()
11387	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
11388	}
11389	}
11390
11391	if (CompLHSTy) *CompLHSTy = LHS.get()->getType();
11392	return Context.getPointerDiffType();
11393	}
11394	}
11395
11396	return InvalidOperands(Loc, LHS, RHS);
11397	}
11398
11399	static bool isScopedEnumerationType(QualType T) {
11400	if (const EnumType *ET = T->getAs<EnumType>())
11401	return ET->getDecl()->isScoped();
11402	return false;
11403	}
11404
11405	static void DiagnoseBadShiftValues(Sema& S, ExprResult &LHS, ExprResult &RHS,
11406	SourceLocation Loc, BinaryOperatorKind Opc,
11407	QualType LHSType) {
11408	// OpenCL 6.3j: shift values are effectively % word size of LHS (more defined),
11409	// so skip remaining warnings as we don't want to modify values within Sema.
11410	if (S.getLangOpts().OpenCL)
11411	return;
11412
11413	if (Opc == BO_Shr &&
11414	LHS.get()->IgnoreParenImpCasts()->getType()->isBooleanType())
11415	S.Diag(Loc, DiagID: diag::warn_shift_bool) << LHS.get()->getSourceRange();
11416
11417	// Check right/shifter operand
11418	Expr::EvalResult RHSResult;
11419	if (RHS.get()->isValueDependent() ||
11420	!RHS.get()->EvaluateAsInt(Result&: RHSResult, Ctx: S.Context))
11421	return;
11422	llvm::APSInt Right = RHSResult.Val.getInt();
11423
11424	if (Right.isNegative()) {
11425	S.DiagRuntimeBehavior(Loc, Statement: RHS.get(),
11426	PD: S.PDiag(DiagID: diag::warn_shift_negative)
11427	<< RHS.get()->getSourceRange());
11428	return;
11429	}
11430
11431	QualType LHSExprType = LHS.get()->getType();
11432	uint64_t LeftSize = S.Context.getTypeSize(T: LHSExprType);
11433	if (LHSExprType->isBitIntType())
11434	LeftSize = S.Context.getIntWidth(T: LHSExprType);
11435	else if (LHSExprType->isFixedPointType()) {
11436	auto FXSema = S.Context.getFixedPointSemantics(Ty: LHSExprType);
11437	LeftSize = FXSema.getWidth() - (unsigned)FXSema.hasUnsignedPadding();
11438	}
11439	if (Right.uge(RHS: LeftSize)) {
11440	S.DiagRuntimeBehavior(Loc, Statement: RHS.get(),
11441	PD: S.PDiag(DiagID: diag::warn_shift_gt_typewidth)
11442	<< RHS.get()->getSourceRange());
11443	return;
11444	}
11445
11446	// FIXME: We probably need to handle fixed point types specially here.
11447	if (Opc != BO_Shl || LHSExprType->isFixedPointType())
11448	return;
11449
11450	// When left shifting an ICE which is signed, we can check for overflow which
11451	// according to C++ standards prior to C++2a has undefined behavior
11452	// ([expr.shift] 5.8/2). Unsigned integers have defined behavior modulo one
11453	// more than the maximum value representable in the result type, so never
11454	// warn for those. (FIXME: Unsigned left-shift overflow in a constant
11455	// expression is still probably a bug.)
11456	Expr::EvalResult LHSResult;
11457	if (LHS.get()->isValueDependent() ||
11458	LHSType->hasUnsignedIntegerRepresentation() ||
11459	!LHS.get()->EvaluateAsInt(Result&: LHSResult, Ctx: S.Context))
11460	return;
11461	llvm::APSInt Left = LHSResult.Val.getInt();
11462
11463	// Don't warn if signed overflow is defined, then all the rest of the
11464	// diagnostics will not be triggered because the behavior is defined.
11465	// Also don't warn in C++20 mode (and newer), as signed left shifts
11466	// always wrap and never overflow.
11467	if (S.getLangOpts().isSignedOverflowDefined() || S.getLangOpts().CPlusPlus20)
11468	return;
11469
11470	// If LHS does not have a non-negative value then, the
11471	// behavior is undefined before C++2a. Warn about it.
11472	if (Left.isNegative()) {
11473	S.DiagRuntimeBehavior(Loc, Statement: LHS.get(),
11474	PD: S.PDiag(DiagID: diag::warn_shift_lhs_negative)
11475	<< LHS.get()->getSourceRange());
11476	return;
11477	}
11478
11479	llvm::APInt ResultBits =
11480	static_cast<llvm::APInt &>(Right) + Left.getSignificantBits();
11481	if (ResultBits.ule(RHS: LeftSize))
11482	return;
11483	llvm::APSInt Result = Left.extend(width: ResultBits.getLimitedValue());
11484	Result = Result.shl(ShiftAmt: Right);
11485
11486	// Print the bit representation of the signed integer as an unsigned
11487	// hexadecimal number.
11488	SmallString<40> HexResult;
11489	Result.toString(Str&: HexResult, Radix: 16, /*Signed =*/false, /*Literal =*/formatAsCLiteral: true);
11490
11491	// If we are only missing a sign bit, this is less likely to result in actual
11492	// bugs -- if the result is cast back to an unsigned type, it will have the
11493	// expected value. Thus we place this behind a different warning that can be
11494	// turned off separately if needed.
11495	if (ResultBits - 1 == LeftSize) {
11496	S.Diag(Loc, DiagID: diag::warn_shift_result_sets_sign_bit)
11497	<< HexResult << LHSType
11498	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
11499	return;
11500	}
11501
11502	S.Diag(Loc, DiagID: diag::warn_shift_result_gt_typewidth)
11503	<< HexResult.str() << Result.getSignificantBits() << LHSType
11504	<< Left.getBitWidth() << LHS.get()->getSourceRange()
11505	<< RHS.get()->getSourceRange();
11506	}
11507
11508	/// Return the resulting type when a vector is shifted
11509	/// by a scalar or vector shift amount.
11510	static QualType checkVectorShift(Sema &S, ExprResult &LHS, ExprResult &RHS,
11511	SourceLocation Loc, bool IsCompAssign) {
11512	// OpenCL v1.1 s6.3.j says RHS can be a vector only if LHS is a vector.
11513	if ((S.LangOpts.OpenCL || S.LangOpts.ZVector) &&
11514	!LHS.get()->getType()->isVectorType()) {
11515	S.Diag(Loc, DiagID: diag::err_shift_rhs_only_vector)
11516	<< RHS.get()->getType() << LHS.get()->getType()
11517	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
11518	return QualType();
11519	}
11520
11521	if (!IsCompAssign) {
11522	LHS = S.UsualUnaryConversions(E: LHS.get());
11523	if (LHS.isInvalid()) return QualType();
11524	}
11525
11526	RHS = S.UsualUnaryConversions(E: RHS.get());
11527	if (RHS.isInvalid()) return QualType();
11528
11529	QualType LHSType = LHS.get()->getType();
11530	// Note that LHS might be a scalar because the routine calls not only in
11531	// OpenCL case.
11532	const VectorType *LHSVecTy = LHSType->getAs<VectorType>();
11533	QualType LHSEleType = LHSVecTy ? LHSVecTy->getElementType() : LHSType;
11534
11535	// Note that RHS might not be a vector.
11536	QualType RHSType = RHS.get()->getType();
11537	const VectorType *RHSVecTy = RHSType->getAs<VectorType>();
11538	QualType RHSEleType = RHSVecTy ? RHSVecTy->getElementType() : RHSType;
11539
11540	// Do not allow shifts for boolean vectors.
11541	if ((LHSVecTy && LHSVecTy->isExtVectorBoolType()) ||
11542	(RHSVecTy && RHSVecTy->isExtVectorBoolType())) {
11543	S.Diag(Loc, DiagID: diag::err_typecheck_invalid_operands)
11544	<< LHS.get()->getType() << RHS.get()->getType()
11545	<< LHS.get()->getSourceRange();
11546	return QualType();
11547	}
11548
11549	// The operands need to be integers.
11550	if (!LHSEleType->isIntegerType()) {
11551	S.Diag(Loc, DiagID: diag::err_typecheck_expect_int)
11552	<< LHS.get()->getType() << LHS.get()->getSourceRange();
11553	return QualType();
11554	}
11555
11556	if (!RHSEleType->isIntegerType()) {
11557	S.Diag(Loc, DiagID: diag::err_typecheck_expect_int)
11558	<< RHS.get()->getType() << RHS.get()->getSourceRange();
11559	return QualType();
11560	}
11561
11562	if (!LHSVecTy) {
11563	assert(RHSVecTy);
11564	if (IsCompAssign)
11565	return RHSType;
11566	if (LHSEleType != RHSEleType) {
11567	LHS = S.ImpCastExprToType(E: LHS.get(),Type: RHSEleType, CK: CK_IntegralCast);
11568	LHSEleType = RHSEleType;
11569	}
11570	QualType VecTy =
11571	S.Context.getExtVectorType(VectorType: LHSEleType, NumElts: RHSVecTy->getNumElements());
11572	LHS = S.ImpCastExprToType(E: LHS.get(), Type: VecTy, CK: CK_VectorSplat);
11573	LHSType = VecTy;
11574	} else if (RHSVecTy) {
11575	// OpenCL v1.1 s6.3.j says that for vector types, the operators
11576	// are applied component-wise. So if RHS is a vector, then ensure
11577	// that the number of elements is the same as LHS...
11578	if (RHSVecTy->getNumElements() != LHSVecTy->getNumElements()) {
11579	S.Diag(Loc, DiagID: diag::err_typecheck_vector_lengths_not_equal)
11580	<< LHS.get()->getType() << RHS.get()->getType()
11581	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
11582	return QualType();
11583	}
11584	if (!S.LangOpts.OpenCL && !S.LangOpts.ZVector) {
11585	const BuiltinType *LHSBT = LHSEleType->getAs<clang::BuiltinType>();
11586	const BuiltinType *RHSBT = RHSEleType->getAs<clang::BuiltinType>();
11587	if (LHSBT != RHSBT &&
11588	S.Context.getTypeSize(T: LHSBT) != S.Context.getTypeSize(T: RHSBT)) {
11589	S.Diag(Loc, DiagID: diag::warn_typecheck_vector_element_sizes_not_equal)
11590	<< LHS.get()->getType() << RHS.get()->getType()
11591	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
11592	}
11593	}
11594	} else {
11595	// ...else expand RHS to match the number of elements in LHS.
11596	QualType VecTy =
11597	S.Context.getExtVectorType(VectorType: RHSEleType, NumElts: LHSVecTy->getNumElements());
11598	RHS = S.ImpCastExprToType(E: RHS.get(), Type: VecTy, CK: CK_VectorSplat);
11599	}
11600
11601	return LHSType;
11602	}
11603
11604	static QualType checkSizelessVectorShift(Sema &S, ExprResult &LHS,
11605	ExprResult &RHS, SourceLocation Loc,
11606	bool IsCompAssign) {
11607	if (!IsCompAssign) {
11608	LHS = S.UsualUnaryConversions(E: LHS.get());
11609	if (LHS.isInvalid())
11610	return QualType();
11611	}
11612
11613	RHS = S.UsualUnaryConversions(E: RHS.get());
11614	if (RHS.isInvalid())
11615	return QualType();
11616
11617	QualType LHSType = LHS.get()->getType();
11618	const BuiltinType *LHSBuiltinTy = LHSType->castAs<BuiltinType>();
11619	QualType LHSEleType = LHSType->isSveVLSBuiltinType()
11620	? LHSBuiltinTy->getSveEltType(Ctx: S.getASTContext())
11621	: LHSType;
11622
11623	// Note that RHS might not be a vector
11624	QualType RHSType = RHS.get()->getType();
11625	const BuiltinType *RHSBuiltinTy = RHSType->castAs<BuiltinType>();
11626	QualType RHSEleType = RHSType->isSveVLSBuiltinType()
11627	? RHSBuiltinTy->getSveEltType(Ctx: S.getASTContext())
11628	: RHSType;
11629
11630	if ((LHSBuiltinTy && LHSBuiltinTy->isSVEBool()) ||
11631	(RHSBuiltinTy && RHSBuiltinTy->isSVEBool())) {
11632	S.Diag(Loc, DiagID: diag::err_typecheck_invalid_operands)
11633	<< LHSType << RHSType << LHS.get()->getSourceRange();
11634	return QualType();
11635	}
11636
11637	if (!LHSEleType->isIntegerType()) {
11638	S.Diag(Loc, DiagID: diag::err_typecheck_expect_int)
11639	<< LHS.get()->getType() << LHS.get()->getSourceRange();
11640	return QualType();
11641	}
11642
11643	if (!RHSEleType->isIntegerType()) {
11644	S.Diag(Loc, DiagID: diag::err_typecheck_expect_int)
11645	<< RHS.get()->getType() << RHS.get()->getSourceRange();
11646	return QualType();
11647	}
11648
11649	if (LHSType->isSveVLSBuiltinType() && RHSType->isSveVLSBuiltinType() &&
11650	(S.Context.getBuiltinVectorTypeInfo(VecTy: LHSBuiltinTy).EC !=
11651	S.Context.getBuiltinVectorTypeInfo(VecTy: RHSBuiltinTy).EC)) {
11652	S.Diag(Loc, DiagID: diag::err_typecheck_invalid_operands)
11653	<< LHSType << RHSType << LHS.get()->getSourceRange()
11654	<< RHS.get()->getSourceRange();
11655	return QualType();
11656	}
11657
11658	if (!LHSType->isSveVLSBuiltinType()) {
11659	assert(RHSType->isSveVLSBuiltinType());
11660	if (IsCompAssign)
11661	return RHSType;
11662	if (LHSEleType != RHSEleType) {
11663	LHS = S.ImpCastExprToType(E: LHS.get(), Type: RHSEleType, CK: clang::CK_IntegralCast);
11664	LHSEleType = RHSEleType;
11665	}
11666	const llvm::ElementCount VecSize =
11667	S.Context.getBuiltinVectorTypeInfo(VecTy: RHSBuiltinTy).EC;
11668	QualType VecTy =
11669	S.Context.getScalableVectorType(EltTy: LHSEleType, NumElts: VecSize.getKnownMinValue());
11670	LHS = S.ImpCastExprToType(E: LHS.get(), Type: VecTy, CK: clang::CK_VectorSplat);
11671	LHSType = VecTy;
11672	} else if (RHSBuiltinTy && RHSBuiltinTy->isSveVLSBuiltinType()) {
11673	if (S.Context.getTypeSize(T: RHSBuiltinTy) !=
11674	S.Context.getTypeSize(T: LHSBuiltinTy)) {
11675	S.Diag(Loc, DiagID: diag::err_typecheck_vector_lengths_not_equal)
11676	<< LHSType << RHSType << LHS.get()->getSourceRange()
11677	<< RHS.get()->getSourceRange();
11678	return QualType();
11679	}
11680	} else {
11681	const llvm::ElementCount VecSize =
11682	S.Context.getBuiltinVectorTypeInfo(VecTy: LHSBuiltinTy).EC;
11683	if (LHSEleType != RHSEleType) {
11684	RHS = S.ImpCastExprToType(E: RHS.get(), Type: LHSEleType, CK: clang::CK_IntegralCast);
11685	RHSEleType = LHSEleType;
11686	}
11687	QualType VecTy =
11688	S.Context.getScalableVectorType(EltTy: RHSEleType, NumElts: VecSize.getKnownMinValue());
11689	RHS = S.ImpCastExprToType(E: RHS.get(), Type: VecTy, CK: CK_VectorSplat);
11690	}
11691
11692	return LHSType;
11693	}
11694
11695	// C99 6.5.7
11696	QualType Sema::CheckShiftOperands(ExprResult &LHS, ExprResult &RHS,
11697	SourceLocation Loc, BinaryOperatorKind Opc,
11698	bool IsCompAssign) {
11699	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
11700
11701	// Vector shifts promote their scalar inputs to vector type.
11702	if (LHS.get()->getType()->isVectorType() ||
11703	RHS.get()->getType()->isVectorType()) {
11704	if (LangOpts.ZVector) {
11705	// The shift operators for the z vector extensions work basically
11706	// like general shifts, except that neither the LHS nor the RHS is
11707	// allowed to be a "vector bool".
11708	if (auto LHSVecType = LHS.get()->getType()->getAs<VectorType>())
11709	if (LHSVecType->getVectorKind() == VectorKind::AltiVecBool)
11710	return InvalidOperands(Loc, LHS, RHS);
11711	if (auto RHSVecType = RHS.get()->getType()->getAs<VectorType>())
11712	if (RHSVecType->getVectorKind() == VectorKind::AltiVecBool)
11713	return InvalidOperands(Loc, LHS, RHS);
11714	}
11715	return checkVectorShift(S&: *this, LHS, RHS, Loc, IsCompAssign);
11716	}
11717
11718	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
11719	RHS.get()->getType()->isSveVLSBuiltinType())
11720	return checkSizelessVectorShift(S&: *this, LHS, RHS, Loc, IsCompAssign);
11721
11722	// Shifts don't perform usual arithmetic conversions, they just do integer
11723	// promotions on each operand. C99 6.5.7p3
11724
11725	// For the LHS, do usual unary conversions, but then reset them away
11726	// if this is a compound assignment.
11727	ExprResult OldLHS = LHS;
11728	LHS = UsualUnaryConversions(E: LHS.get());
11729	if (LHS.isInvalid())
11730	return QualType();
11731	QualType LHSType = LHS.get()->getType();
11732	if (IsCompAssign) LHS = OldLHS;
11733
11734	// The RHS is simpler.
11735	RHS = UsualUnaryConversions(E: RHS.get());
11736	if (RHS.isInvalid())
11737	return QualType();
11738	QualType RHSType = RHS.get()->getType();
11739
11740	// C99 6.5.7p2: Each of the operands shall have integer type.
11741	// Embedded-C 4.1.6.2.2: The LHS may also be fixed-point.
11742	if ((!LHSType->isFixedPointOrIntegerType() &&
11743	!LHSType->hasIntegerRepresentation()) ||
11744	!RHSType->hasIntegerRepresentation())
11745	return InvalidOperands(Loc, LHS, RHS);
11746
11747	// C++0x: Don't allow scoped enums. FIXME: Use something better than
11748	// hasIntegerRepresentation() above instead of this.
11749	if (isScopedEnumerationType(T: LHSType) ||
11750	isScopedEnumerationType(T: RHSType)) {
11751	return InvalidOperands(Loc, LHS, RHS);
11752	}
11753	DiagnoseBadShiftValues(S&: *this, LHS, RHS, Loc, Opc, LHSType);
11754
11755	// "The type of the result is that of the promoted left operand."
11756	return LHSType;
11757	}
11758
11759	/// Diagnose bad pointer comparisons.
11760	static void diagnoseDistinctPointerComparison(Sema &S, SourceLocation Loc,
11761	ExprResult &LHS, ExprResult &RHS,
11762	bool IsError) {
11763	S.Diag(Loc, DiagID: IsError ? diag::err_typecheck_comparison_of_distinct_pointers
11764	: diag::ext_typecheck_comparison_of_distinct_pointers)
11765	<< LHS.get()->getType() << RHS.get()->getType()
11766	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
11767	}
11768
11769	/// Returns false if the pointers are converted to a composite type,
11770	/// true otherwise.
11771	static bool convertPointersToCompositeType(Sema &S, SourceLocation Loc,
11772	ExprResult &LHS, ExprResult &RHS) {
11773	// C++ [expr.rel]p2:
11774	// [...] Pointer conversions (4.10) and qualification
11775	// conversions (4.4) are performed on pointer operands (or on
11776	// a pointer operand and a null pointer constant) to bring
11777	// them to their composite pointer type. [...]
11778	//
11779	// C++ [expr.eq]p1 uses the same notion for (in)equality
11780	// comparisons of pointers.
11781
11782	QualType LHSType = LHS.get()->getType();
11783	QualType RHSType = RHS.get()->getType();
11784	assert(LHSType->isPointerType() || RHSType->isPointerType() ||
11785	LHSType->isMemberPointerType() || RHSType->isMemberPointerType());
11786
11787	QualType T = S.FindCompositePointerType(Loc, E1&: LHS, E2&: RHS);
11788	if (T.isNull()) {
11789	if ((LHSType->isAnyPointerType() || LHSType->isMemberPointerType()) &&
11790	(RHSType->isAnyPointerType() || RHSType->isMemberPointerType()))
11791	diagnoseDistinctPointerComparison(S, Loc, LHS, RHS, /*isError*/IsError: true);
11792	else
11793	S.InvalidOperands(Loc, LHS, RHS);
11794	return true;
11795	}
11796
11797	return false;
11798	}
11799
11800	static void diagnoseFunctionPointerToVoidComparison(Sema &S, SourceLocation Loc,
11801	ExprResult &LHS,
11802	ExprResult &RHS,
11803	bool IsError) {
11804	S.Diag(Loc, DiagID: IsError ? diag::err_typecheck_comparison_of_fptr_to_void
11805	: diag::ext_typecheck_comparison_of_fptr_to_void)
11806	<< LHS.get()->getType() << RHS.get()->getType()
11807	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
11808	}
11809
11810	static bool isObjCObjectLiteral(ExprResult &E) {
11811	switch (E.get()->IgnoreParenImpCasts()->getStmtClass()) {
11812	case Stmt::ObjCArrayLiteralClass:
11813	case Stmt::ObjCDictionaryLiteralClass:
11814	case Stmt::ObjCStringLiteralClass:
11815	case Stmt::ObjCBoxedExprClass:
11816	return true;
11817	default:
11818	// Note that ObjCBoolLiteral is NOT an object literal!
11819	return false;
11820	}
11821	}
11822
11823	static bool hasIsEqualMethod(Sema &S, const Expr *LHS, const Expr *RHS) {
11824	const ObjCObjectPointerType *Type =
11825	LHS->getType()->getAs<ObjCObjectPointerType>();
11826
11827	// If this is not actually an Objective-C object, bail out.
11828	if (!Type)
11829	return false;
11830
11831	// Get the LHS object's interface type.
11832	QualType InterfaceType = Type->getPointeeType();
11833
11834	// If the RHS isn't an Objective-C object, bail out.
11835	if (!RHS->getType()->isObjCObjectPointerType())
11836	return false;
11837
11838	// Try to find the -isEqual: method.
11839	Selector IsEqualSel = S.ObjC().NSAPIObj->getIsEqualSelector();
11840	ObjCMethodDecl *Method =
11841	S.ObjC().LookupMethodInObjectType(Sel: IsEqualSel, Ty: InterfaceType,
11842	/*IsInstance=*/true);
11843	if (!Method) {
11844	if (Type->isObjCIdType()) {
11845	// For 'id', just check the global pool.
11846	Method =
11847	S.ObjC().LookupInstanceMethodInGlobalPool(Sel: IsEqualSel, R: SourceRange(),
11848	/*receiverId=*/receiverIdOrClass: true);
11849	} else {
11850	// Check protocols.
11851	Method = S.ObjC().LookupMethodInQualifiedType(Sel: IsEqualSel, OPT: Type,
11852	/*IsInstance=*/true);
11853	}
11854	}
11855
11856	if (!Method)
11857	return false;
11858
11859	QualType T = Method->parameters()[0]->getType();
11860	if (!T->isObjCObjectPointerType())
11861	return false;
11862
11863	QualType R = Method->getReturnType();
11864	if (!R->isScalarType())
11865	return false;
11866
11867	return true;
11868	}
11869
11870	static void diagnoseObjCLiteralComparison(Sema &S, SourceLocation Loc,
11871	ExprResult &LHS, ExprResult &RHS,
11872	BinaryOperator::Opcode Opc){
11873	Expr *Literal;
11874	Expr *Other;
11875	if (isObjCObjectLiteral(E&: LHS)) {
11876	Literal = LHS.get();
11877	Other = RHS.get();
11878	} else {
11879	Literal = RHS.get();
11880	Other = LHS.get();
11881	}
11882
11883	// Don't warn on comparisons against nil.
11884	Other = Other->IgnoreParenCasts();
11885	if (Other->isNullPointerConstant(Ctx&: S.getASTContext(),
11886	NPC: Expr::NPC_ValueDependentIsNotNull))
11887	return;
11888
11889	// This should be kept in sync with warn_objc_literal_comparison.
11890	// LK_String should always be after the other literals, since it has its own
11891	// warning flag.
11892	SemaObjC::ObjCLiteralKind LiteralKind = S.ObjC().CheckLiteralKind(FromE: Literal);
11893	assert(LiteralKind != SemaObjC::LK_Block);
11894	if (LiteralKind == SemaObjC::LK_None) {
11895	llvm_unreachable("Unknown Objective-C object literal kind");
11896	}
11897
11898	if (LiteralKind == SemaObjC::LK_String)
11899	S.Diag(Loc, DiagID: diag::warn_objc_string_literal_comparison)
11900	<< Literal->getSourceRange();
11901	else
11902	S.Diag(Loc, DiagID: diag::warn_objc_literal_comparison)
11903	<< LiteralKind << Literal->getSourceRange();
11904
11905	if (BinaryOperator::isEqualityOp(Opc) &&
11906	hasIsEqualMethod(S, LHS: LHS.get(), RHS: RHS.get())) {
11907	SourceLocation Start = LHS.get()->getBeginLoc();
11908	SourceLocation End = S.getLocForEndOfToken(Loc: RHS.get()->getEndLoc());
11909	CharSourceRange OpRange =
11910	CharSourceRange::getCharRange(B: Loc, E: S.getLocForEndOfToken(Loc));
11911
11912	S.Diag(Loc, DiagID: diag::note_objc_literal_comparison_isequal)
11913	<< FixItHint::CreateInsertion(InsertionLoc: Start, Code: Opc == BO_EQ ? "[" : "![")
11914	<< FixItHint::CreateReplacement(RemoveRange: OpRange, Code: " isEqual:")
11915	<< FixItHint::CreateInsertion(InsertionLoc: End, Code: "]");
11916	}
11917	}
11918
11919	/// Warns on !x < y, !x & y where !(x < y), !(x & y) was probably intended.
11920	static void diagnoseLogicalNotOnLHSofCheck(Sema &S, ExprResult &LHS,
11921	ExprResult &RHS, SourceLocation Loc,
11922	BinaryOperatorKind Opc) {
11923	// Check that left hand side is !something.
11924	UnaryOperator *UO = dyn_cast<UnaryOperator>(Val: LHS.get()->IgnoreImpCasts());
11925	if (!UO || UO->getOpcode() != UO_LNot) return;
11926
11927	// Only check if the right hand side is non-bool arithmetic type.
11928	if (RHS.get()->isKnownToHaveBooleanValue()) return;
11929
11930	// Make sure that the something in !something is not bool.
11931	Expr *SubExpr = UO->getSubExpr()->IgnoreImpCasts();
11932	if (SubExpr->isKnownToHaveBooleanValue()) return;
11933
11934	// Emit warning.
11935	bool IsBitwiseOp = Opc == BO_And || Opc == BO_Or || Opc == BO_Xor;
11936	S.Diag(Loc: UO->getOperatorLoc(), DiagID: diag::warn_logical_not_on_lhs_of_check)
11937	<< Loc << IsBitwiseOp;
11938
11939	// First note suggest !(x < y)
11940	SourceLocation FirstOpen = SubExpr->getBeginLoc();
11941	SourceLocation FirstClose = RHS.get()->getEndLoc();
11942	FirstClose = S.getLocForEndOfToken(Loc: FirstClose);
11943	if (FirstClose.isInvalid())
11944	FirstOpen = SourceLocation();
11945	S.Diag(Loc: UO->getOperatorLoc(), DiagID: diag::note_logical_not_fix)
11946	<< IsBitwiseOp
11947	<< FixItHint::CreateInsertion(InsertionLoc: FirstOpen, Code: "(")
11948	<< FixItHint::CreateInsertion(InsertionLoc: FirstClose, Code: ")");
11949
11950	// Second note suggests (!x) < y
11951	SourceLocation SecondOpen = LHS.get()->getBeginLoc();
11952	SourceLocation SecondClose = LHS.get()->getEndLoc();
11953	SecondClose = S.getLocForEndOfToken(Loc: SecondClose);
11954	if (SecondClose.isInvalid())
11955	SecondOpen = SourceLocation();
11956	S.Diag(Loc: UO->getOperatorLoc(), DiagID: diag::note_logical_not_silence_with_parens)
11957	<< FixItHint::CreateInsertion(InsertionLoc: SecondOpen, Code: "(")
11958	<< FixItHint::CreateInsertion(InsertionLoc: SecondClose, Code: ")");
11959	}
11960
11961	// Returns true if E refers to a non-weak array.
11962	static bool checkForArray(const Expr *E) {
11963	const ValueDecl *D = nullptr;
11964	if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(Val: E)) {
11965	D = DR->getDecl();
11966	} else if (const MemberExpr *Mem = dyn_cast<MemberExpr>(Val: E)) {
11967	if (Mem->isImplicitAccess())
11968	D = Mem->getMemberDecl();
11969	}
11970	if (!D)
11971	return false;
11972	return D->getType()->isArrayType() && !D->isWeak();
11973	}
11974
11975	/// Detect patterns ptr + size >= ptr and ptr + size < ptr, where ptr is a
11976	/// pointer and size is an unsigned integer. Return whether the result is
11977	/// always true/false.
11978	static std::optional<bool> isTautologicalBoundsCheck(Sema &S, const Expr *LHS,
11979	const Expr *RHS,
11980	BinaryOperatorKind Opc) {
11981	if (!LHS->getType()->isPointerType() ||
11982	S.getLangOpts().PointerOverflowDefined)
11983	return std::nullopt;
11984
11985	// Canonicalize to >= or < predicate.
11986	switch (Opc) {
11987	case BO_GE:
11988	case BO_LT:
11989	break;
11990	case BO_GT:
11991	std::swap(a&: LHS, b&: RHS);
11992	Opc = BO_LT;
11993	break;
11994	case BO_LE:
11995	std::swap(a&: LHS, b&: RHS);
11996	Opc = BO_GE;
11997	break;
11998	default:
11999	return std::nullopt;
12000	}
12001
12002	auto *BO = dyn_cast<BinaryOperator>(Val: LHS);
12003	if (!BO || BO->getOpcode() != BO_Add)
12004	return std::nullopt;
12005
12006	Expr *Other;
12007	if (Expr::isSameComparisonOperand(E1: BO->getLHS(), E2: RHS))
12008	Other = BO->getRHS();
12009	else if (Expr::isSameComparisonOperand(E1: BO->getRHS(), E2: RHS))
12010	Other = BO->getLHS();
12011	else
12012	return std::nullopt;
12013
12014	if (!Other->getType()->isUnsignedIntegerType())
12015	return std::nullopt;
12016
12017	return Opc == BO_GE;
12018	}
12019
12020	/// Diagnose some forms of syntactically-obvious tautological comparison.
12021	static void diagnoseTautologicalComparison(Sema &S, SourceLocation Loc,
12022	Expr *LHS, Expr *RHS,
12023	BinaryOperatorKind Opc) {
12024	Expr *LHSStripped = LHS->IgnoreParenImpCasts();
12025	Expr *RHSStripped = RHS->IgnoreParenImpCasts();
12026
12027	QualType LHSType = LHS->getType();
12028	QualType RHSType = RHS->getType();
12029	if (LHSType->hasFloatingRepresentation() ||
12030	(LHSType->isBlockPointerType() && !BinaryOperator::isEqualityOp(Opc)) ||
12031	S.inTemplateInstantiation())
12032	return;
12033
12034	// WebAssembly Tables cannot be compared, therefore shouldn't emit
12035	// Tautological diagnostics.
12036	if (LHSType->isWebAssemblyTableType() || RHSType->isWebAssemblyTableType())
12037	return;
12038
12039	// Comparisons between two array types are ill-formed for operator<=>, so
12040	// we shouldn't emit any additional warnings about it.
12041	if (Opc == BO_Cmp && LHSType->isArrayType() && RHSType->isArrayType())
12042	return;
12043
12044	// For non-floating point types, check for self-comparisons of the form
12045	// x == x, x != x, x < x, etc. These always evaluate to a constant, and
12046	// often indicate logic errors in the program.
12047	//
12048	// NOTE: Don't warn about comparison expressions resulting from macro
12049	// expansion. Also don't warn about comparisons which are only self
12050	// comparisons within a template instantiation. The warnings should catch
12051	// obvious cases in the definition of the template anyways. The idea is to
12052	// warn when the typed comparison operator will always evaluate to the same
12053	// result.
12054
12055	// Used for indexing into %select in warn_comparison_always
12056	enum {
12057	AlwaysConstant,
12058	AlwaysTrue,
12059	AlwaysFalse,
12060	AlwaysEqual, // std::strong_ordering::equal from operator<=>
12061	};
12062
12063	// C++1a [array.comp]:
12064	// Equality and relational comparisons ([expr.eq], [expr.rel]) between two
12065	// operands of array type.
12066	// C++2a [depr.array.comp]:
12067	// Equality and relational comparisons ([expr.eq], [expr.rel]) between two
12068	// operands of array type are deprecated.
12069	if (S.getLangOpts().CPlusPlus && LHSStripped->getType()->isArrayType() &&
12070	RHSStripped->getType()->isArrayType()) {
12071	auto IsDeprArrayComparionIgnored =
12072	S.getDiagnostics().isIgnored(DiagID: diag::warn_depr_array_comparison, Loc);
12073	auto DiagID = S.getLangOpts().CPlusPlus26
12074	? diag::warn_array_comparison_cxx26
12075	: !S.getLangOpts().CPlusPlus20 || IsDeprArrayComparionIgnored
12076	? diag::warn_array_comparison
12077	: diag::warn_depr_array_comparison;
12078	S.Diag(Loc, DiagID) << LHS->getSourceRange() << RHS->getSourceRange()
12079	<< LHSStripped->getType() << RHSStripped->getType();
12080	// Carry on to produce the tautological comparison warning, if this
12081	// expression is potentially-evaluated, we can resolve the array to a
12082	// non-weak declaration, and so on.
12083	}
12084
12085	if (!LHS->getBeginLoc().isMacroID() && !RHS->getBeginLoc().isMacroID()) {
12086	if (Expr::isSameComparisonOperand(E1: LHS, E2: RHS)) {
12087	unsigned Result;
12088	switch (Opc) {
12089	case BO_EQ:
12090	case BO_LE:
12091	case BO_GE:
12092	Result = AlwaysTrue;
12093	break;
12094	case BO_NE:
12095	case BO_LT:
12096	case BO_GT:
12097	Result = AlwaysFalse;
12098	break;
12099	case BO_Cmp:
12100	Result = AlwaysEqual;
12101	break;
12102	default:
12103	Result = AlwaysConstant;
12104	break;
12105	}
12106	S.DiagRuntimeBehavior(Loc, Statement: nullptr,
12107	PD: S.PDiag(DiagID: diag::warn_comparison_always)
12108	<< 0 /*self-comparison*/
12109	<< Result);
12110	} else if (checkForArray(E: LHSStripped) && checkForArray(E: RHSStripped)) {
12111	// What is it always going to evaluate to?
12112	unsigned Result;
12113	switch (Opc) {
12114	case BO_EQ: // e.g. array1 == array2
12115	Result = AlwaysFalse;
12116	break;
12117	case BO_NE: // e.g. array1 != array2
12118	Result = AlwaysTrue;
12119	break;
12120	default: // e.g. array1 <= array2
12121	// The best we can say is 'a constant'
12122	Result = AlwaysConstant;
12123	break;
12124	}
12125	S.DiagRuntimeBehavior(Loc, Statement: nullptr,
12126	PD: S.PDiag(DiagID: diag::warn_comparison_always)
12127	<< 1 /*array comparison*/
12128	<< Result);
12129	} else if (std::optional<bool> Res =
12130	isTautologicalBoundsCheck(S, LHS, RHS, Opc)) {
12131	S.DiagRuntimeBehavior(Loc, Statement: nullptr,
12132	PD: S.PDiag(DiagID: diag::warn_comparison_always)
12133	<< 2 /*pointer comparison*/
12134	<< (*Res ? AlwaysTrue : AlwaysFalse));
12135	}
12136	}
12137
12138	if (isa<CastExpr>(Val: LHSStripped))
12139	LHSStripped = LHSStripped->IgnoreParenCasts();
12140	if (isa<CastExpr>(Val: RHSStripped))
12141	RHSStripped = RHSStripped->IgnoreParenCasts();
12142
12143	// Warn about comparisons against a string constant (unless the other
12144	// operand is null); the user probably wants string comparison function.
12145	Expr *LiteralString = nullptr;
12146	Expr *LiteralStringStripped = nullptr;
12147	if ((isa<StringLiteral>(Val: LHSStripped) || isa<ObjCEncodeExpr>(Val: LHSStripped)) &&
12148	!RHSStripped->isNullPointerConstant(Ctx&: S.Context,
12149	NPC: Expr::NPC_ValueDependentIsNull)) {
12150	LiteralString = LHS;
12151	LiteralStringStripped = LHSStripped;
12152	} else if ((isa<StringLiteral>(Val: RHSStripped) ||
12153	isa<ObjCEncodeExpr>(Val: RHSStripped)) &&
12154	!LHSStripped->isNullPointerConstant(Ctx&: S.Context,
12155	NPC: Expr::NPC_ValueDependentIsNull)) {
12156	LiteralString = RHS;
12157	LiteralStringStripped = RHSStripped;
12158	}
12159
12160	if (LiteralString) {
12161	S.DiagRuntimeBehavior(Loc, Statement: nullptr,
12162	PD: S.PDiag(DiagID: diag::warn_stringcompare)
12163	<< isa<ObjCEncodeExpr>(Val: LiteralStringStripped)
12164	<< LiteralString->getSourceRange());
12165	}
12166	}
12167
12168	static ImplicitConversionKind castKindToImplicitConversionKind(CastKind CK) {
12169	switch (CK) {
12170	default: {
12171	#ifndef NDEBUG
12172	llvm::errs() << "unhandled cast kind: " << CastExpr::getCastKindName(CK)
12173	<< "\n";
12174	#endif
12175	llvm_unreachable("unhandled cast kind");
12176	}
12177	case CK_UserDefinedConversion:
12178	return ICK_Identity;
12179	case CK_LValueToRValue:
12180	return ICK_Lvalue_To_Rvalue;
12181	case CK_ArrayToPointerDecay:
12182	return ICK_Array_To_Pointer;
12183	case CK_FunctionToPointerDecay:
12184	return ICK_Function_To_Pointer;
12185	case CK_IntegralCast:
12186	return ICK_Integral_Conversion;
12187	case CK_FloatingCast:
12188	return ICK_Floating_Conversion;
12189	case CK_IntegralToFloating:
12190	case CK_FloatingToIntegral:
12191	return ICK_Floating_Integral;
12192	case CK_IntegralComplexCast:
12193	case CK_FloatingComplexCast:
12194	case CK_FloatingComplexToIntegralComplex:
12195	case CK_IntegralComplexToFloatingComplex:
12196	return ICK_Complex_Conversion;
12197	case CK_FloatingComplexToReal:
12198	case CK_FloatingRealToComplex:
12199	case CK_IntegralComplexToReal:
12200	case CK_IntegralRealToComplex:
12201	return ICK_Complex_Real;
12202	case CK_HLSLArrayRValue:
12203	return ICK_HLSL_Array_RValue;
12204	}
12205	}
12206
12207	static bool checkThreeWayNarrowingConversion(Sema &S, QualType ToType, Expr *E,
12208	QualType FromType,
12209	SourceLocation Loc) {
12210	// Check for a narrowing implicit conversion.
12211	StandardConversionSequence SCS;
12212	SCS.setAsIdentityConversion();
12213	SCS.setToType(Idx: 0, T: FromType);
12214	SCS.setToType(Idx: 1, T: ToType);
12215	if (const auto *ICE = dyn_cast<ImplicitCastExpr>(Val: E))
12216	SCS.Second = castKindToImplicitConversionKind(CK: ICE->getCastKind());
12217
12218	APValue PreNarrowingValue;
12219	QualType PreNarrowingType;
12220	switch (SCS.getNarrowingKind(Context&: S.Context, Converted: E, ConstantValue&: PreNarrowingValue,
12221	ConstantType&: PreNarrowingType,
12222	/*IgnoreFloatToIntegralConversion*/ true)) {
12223	case NK_Dependent_Narrowing:
12224	// Implicit conversion to a narrower type, but the expression is
12225	// value-dependent so we can't tell whether it's actually narrowing.
12226	case NK_Not_Narrowing:
12227	return false;
12228
12229	case NK_Constant_Narrowing:
12230	// Implicit conversion to a narrower type, and the value is not a constant
12231	// expression.
12232	S.Diag(Loc: E->getBeginLoc(), DiagID: diag::err_spaceship_argument_narrowing)
12233	<< /*Constant*/ 1
12234	<< PreNarrowingValue.getAsString(Ctx: S.Context, Ty: PreNarrowingType) << ToType;
12235	return true;
12236
12237	case NK_Variable_Narrowing:
12238	// Implicit conversion to a narrower type, and the value is not a constant
12239	// expression.
12240	case NK_Type_Narrowing:
12241	S.Diag(Loc: E->getBeginLoc(), DiagID: diag::err_spaceship_argument_narrowing)
12242	<< /*Constant*/ 0 << FromType << ToType;
12243	// TODO: It's not a constant expression, but what if the user intended it
12244	// to be? Can we produce notes to help them figure out why it isn't?
12245	return true;
12246	}
12247	llvm_unreachable("unhandled case in switch");
12248	}
12249
12250	static QualType checkArithmeticOrEnumeralThreeWayCompare(Sema &S,
12251	ExprResult &LHS,
12252	ExprResult &RHS,
12253	SourceLocation Loc) {
12254	QualType LHSType = LHS.get()->getType();
12255	QualType RHSType = RHS.get()->getType();
12256	// Dig out the original argument type and expression before implicit casts
12257	// were applied. These are the types/expressions we need to check the
12258	// [expr.spaceship] requirements against.
12259	ExprResult LHSStripped = LHS.get()->IgnoreParenImpCasts();
12260	ExprResult RHSStripped = RHS.get()->IgnoreParenImpCasts();
12261	QualType LHSStrippedType = LHSStripped.get()->getType();
12262	QualType RHSStrippedType = RHSStripped.get()->getType();
12263
12264	// C++2a [expr.spaceship]p3: If one of the operands is of type bool and the
12265	// other is not, the program is ill-formed.
12266	if (LHSStrippedType->isBooleanType() != RHSStrippedType->isBooleanType()) {
12267	S.InvalidOperands(Loc, LHS&: LHSStripped, RHS&: RHSStripped);
12268	return QualType();
12269	}
12270
12271	// FIXME: Consider combining this with checkEnumArithmeticConversions.
12272	int NumEnumArgs = (int)LHSStrippedType->isEnumeralType() +
12273	RHSStrippedType->isEnumeralType();
12274	if (NumEnumArgs == 1) {
12275	bool LHSIsEnum = LHSStrippedType->isEnumeralType();
12276	QualType OtherTy = LHSIsEnum ? RHSStrippedType : LHSStrippedType;
12277	if (OtherTy->hasFloatingRepresentation()) {
12278	S.InvalidOperands(Loc, LHS&: LHSStripped, RHS&: RHSStripped);
12279	return QualType();
12280	}
12281	}
12282	if (NumEnumArgs == 2) {
12283	// C++2a [expr.spaceship]p5: If both operands have the same enumeration
12284	// type E, the operator yields the result of converting the operands
12285	// to the underlying type of E and applying <=> to the converted operands.
12286	if (!S.Context.hasSameUnqualifiedType(T1: LHSStrippedType, T2: RHSStrippedType)) {
12287	S.InvalidOperands(Loc, LHS, RHS);
12288	return QualType();
12289	}
12290	QualType IntType =
12291	LHSStrippedType->castAs<EnumType>()->getDecl()->getIntegerType();
12292	assert(IntType->isArithmeticType());
12293
12294	// We can't use `CK_IntegralCast` when the underlying type is 'bool', so we
12295	// promote the boolean type, and all other promotable integer types, to
12296	// avoid this.
12297	if (S.Context.isPromotableIntegerType(T: IntType))
12298	IntType = S.Context.getPromotedIntegerType(PromotableType: IntType);
12299
12300	LHS = S.ImpCastExprToType(E: LHS.get(), Type: IntType, CK: CK_IntegralCast);
12301	RHS = S.ImpCastExprToType(E: RHS.get(), Type: IntType, CK: CK_IntegralCast);
12302	LHSType = RHSType = IntType;
12303	}
12304
12305	// C++2a [expr.spaceship]p4: If both operands have arithmetic types, the
12306	// usual arithmetic conversions are applied to the operands.
12307	QualType Type =
12308	S.UsualArithmeticConversions(LHS, RHS, Loc, ACK: ArithConvKind::Comparison);
12309	if (LHS.isInvalid() || RHS.isInvalid())
12310	return QualType();
12311	if (Type.isNull())
12312	return S.InvalidOperands(Loc, LHS, RHS);
12313
12314	std::optional<ComparisonCategoryType> CCT =
12315	getComparisonCategoryForBuiltinCmp(T: Type);
12316	if (!CCT)
12317	return S.InvalidOperands(Loc, LHS, RHS);
12318
12319	bool HasNarrowing = checkThreeWayNarrowingConversion(
12320	S, ToType: Type, E: LHS.get(), FromType: LHSType, Loc: LHS.get()->getBeginLoc());
12321	HasNarrowing |= checkThreeWayNarrowingConversion(S, ToType: Type, E: RHS.get(), FromType: RHSType,
12322	Loc: RHS.get()->getBeginLoc());
12323	if (HasNarrowing)
12324	return QualType();
12325
12326	assert(!Type.isNull() && "composite type for <=> has not been set");
12327
12328	return S.CheckComparisonCategoryType(
12329	Kind: *CCT, Loc, Usage: Sema::ComparisonCategoryUsage::OperatorInExpression);
12330	}
12331
12332	static QualType checkArithmeticOrEnumeralCompare(Sema &S, ExprResult &LHS,
12333	ExprResult &RHS,
12334	SourceLocation Loc,
12335	BinaryOperatorKind Opc) {
12336	if (Opc == BO_Cmp)
12337	return checkArithmeticOrEnumeralThreeWayCompare(S, LHS, RHS, Loc);
12338
12339	// C99 6.5.8p3 / C99 6.5.9p4
12340	QualType Type =
12341	S.UsualArithmeticConversions(LHS, RHS, Loc, ACK: ArithConvKind::Comparison);
12342	if (LHS.isInvalid() || RHS.isInvalid())
12343	return QualType();
12344	if (Type.isNull())
12345	return S.InvalidOperands(Loc, LHS, RHS);
12346	assert(Type->isArithmeticType() || Type->isEnumeralType());
12347
12348	if (Type->isAnyComplexType() && BinaryOperator::isRelationalOp(Opc))
12349	return S.InvalidOperands(Loc, LHS, RHS);
12350
12351	// Check for comparisons of floating point operands using != and ==.
12352	if (Type->hasFloatingRepresentation())
12353	S.CheckFloatComparison(Loc, LHS: LHS.get(), RHS: RHS.get(), Opcode: Opc);
12354
12355	// The result of comparisons is 'bool' in C++, 'int' in C.
12356	return S.Context.getLogicalOperationType();
12357	}
12358
12359	void Sema::CheckPtrComparisonWithNullChar(ExprResult &E, ExprResult &NullE) {
12360	if (!NullE.get()->getType()->isAnyPointerType())
12361	return;
12362	int NullValue = PP.isMacroDefined(Id: "NULL") ? 0 : 1;
12363	if (!E.get()->getType()->isAnyPointerType() &&
12364	E.get()->isNullPointerConstant(Ctx&: Context,
12365	NPC: Expr::NPC_ValueDependentIsNotNull) ==
12366	Expr::NPCK_ZeroExpression) {
12367	if (const auto *CL = dyn_cast<CharacterLiteral>(Val: E.get())) {
12368	if (CL->getValue() == 0)
12369	Diag(Loc: E.get()->getExprLoc(), DiagID: diag::warn_pointer_compare)
12370	<< NullValue
12371	<< FixItHint::CreateReplacement(RemoveRange: E.get()->getExprLoc(),
12372	Code: NullValue ? "NULL" : "(void *)0");
12373	} else if (const auto *CE = dyn_cast<CStyleCastExpr>(Val: E.get())) {
12374	TypeSourceInfo *TI = CE->getTypeInfoAsWritten();
12375	QualType T = Context.getCanonicalType(T: TI->getType()).getUnqualifiedType();
12376	if (T == Context.CharTy)
12377	Diag(Loc: E.get()->getExprLoc(), DiagID: diag::warn_pointer_compare)
12378	<< NullValue
12379	<< FixItHint::CreateReplacement(RemoveRange: E.get()->getExprLoc(),
12380	Code: NullValue ? "NULL" : "(void *)0");
12381	}
12382	}
12383	}
12384
12385	// C99 6.5.8, C++ [expr.rel]
12386	QualType Sema::CheckCompareOperands(ExprResult &LHS, ExprResult &RHS,
12387	SourceLocation Loc,
12388	BinaryOperatorKind Opc) {
12389	bool IsRelational = BinaryOperator::isRelationalOp(Opc);
12390	bool IsThreeWay = Opc == BO_Cmp;
12391	bool IsOrdered = IsRelational || IsThreeWay;
12392	auto IsAnyPointerType = [](ExprResult E) {
12393	QualType Ty = E.get()->getType();
12394	return Ty->isPointerType() || Ty->isMemberPointerType();
12395	};
12396
12397	// C++2a [expr.spaceship]p6: If at least one of the operands is of pointer
12398	// type, array-to-pointer, ..., conversions are performed on both operands to
12399	// bring them to their composite type.
12400	// Otherwise, all comparisons expect an rvalue, so convert to rvalue before
12401	// any type-related checks.
12402	if (!IsThreeWay || IsAnyPointerType(LHS) || IsAnyPointerType(RHS)) {
12403	LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
12404	if (LHS.isInvalid())
12405	return QualType();
12406	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
12407	if (RHS.isInvalid())
12408	return QualType();
12409	} else {
12410	LHS = DefaultLvalueConversion(E: LHS.get());
12411	if (LHS.isInvalid())
12412	return QualType();
12413	RHS = DefaultLvalueConversion(E: RHS.get());
12414	if (RHS.isInvalid())
12415	return QualType();
12416	}
12417
12418	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/true);
12419	if (!getLangOpts().CPlusPlus && BinaryOperator::isEqualityOp(Opc)) {
12420	CheckPtrComparisonWithNullChar(E&: LHS, NullE&: RHS);
12421	CheckPtrComparisonWithNullChar(E&: RHS, NullE&: LHS);
12422	}
12423
12424	// Handle vector comparisons separately.
12425	if (LHS.get()->getType()->isVectorType() ||
12426	RHS.get()->getType()->isVectorType())
12427	return CheckVectorCompareOperands(LHS, RHS, Loc, Opc);
12428
12429	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
12430	RHS.get()->getType()->isSveVLSBuiltinType())
12431	return CheckSizelessVectorCompareOperands(LHS, RHS, Loc, Opc);
12432
12433	diagnoseLogicalNotOnLHSofCheck(S&: *this, LHS, RHS, Loc, Opc);
12434	diagnoseTautologicalComparison(S&: *this, Loc, LHS: LHS.get(), RHS: RHS.get(), Opc);
12435
12436	QualType LHSType = LHS.get()->getType();
12437	QualType RHSType = RHS.get()->getType();
12438	if ((LHSType->isArithmeticType() || LHSType->isEnumeralType()) &&
12439	(RHSType->isArithmeticType() || RHSType->isEnumeralType()))
12440	return checkArithmeticOrEnumeralCompare(S&: *this, LHS, RHS, Loc, Opc);
12441
12442	if ((LHSType->isPointerType() &&
12443	LHSType->getPointeeType().isWebAssemblyReferenceType()) ||
12444	(RHSType->isPointerType() &&
12445	RHSType->getPointeeType().isWebAssemblyReferenceType()))
12446	return InvalidOperands(Loc, LHS, RHS);
12447
12448	const Expr::NullPointerConstantKind LHSNullKind =
12449	LHS.get()->isNullPointerConstant(Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNull);
12450	const Expr::NullPointerConstantKind RHSNullKind =
12451	RHS.get()->isNullPointerConstant(Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNull);
12452	bool LHSIsNull = LHSNullKind != Expr::NPCK_NotNull;
12453	bool RHSIsNull = RHSNullKind != Expr::NPCK_NotNull;
12454
12455	auto computeResultTy = [&]() {
12456	if (Opc != BO_Cmp)
12457	return Context.getLogicalOperationType();
12458	assert(getLangOpts().CPlusPlus);
12459	assert(Context.hasSameType(LHS.get()->getType(), RHS.get()->getType()));
12460
12461	QualType CompositeTy = LHS.get()->getType();
12462	assert(!CompositeTy->isReferenceType());
12463
12464	std::optional<ComparisonCategoryType> CCT =
12465	getComparisonCategoryForBuiltinCmp(T: CompositeTy);
12466	if (!CCT)
12467	return InvalidOperands(Loc, LHS, RHS);
12468
12469	if (CompositeTy->isPointerType() && LHSIsNull != RHSIsNull) {
12470	// P0946R0: Comparisons between a null pointer constant and an object
12471	// pointer result in std::strong_equality, which is ill-formed under
12472	// P1959R0.
12473	Diag(Loc, DiagID: diag::err_typecheck_three_way_comparison_of_pointer_and_zero)
12474	<< (LHSIsNull ? LHS.get()->getSourceRange()
12475	: RHS.get()->getSourceRange());
12476	return QualType();
12477	}
12478
12479	return CheckComparisonCategoryType(
12480	Kind: *CCT, Loc, Usage: ComparisonCategoryUsage::OperatorInExpression);
12481	};
12482
12483	if (!IsOrdered && LHSIsNull != RHSIsNull) {
12484	bool IsEquality = Opc == BO_EQ;
12485	if (RHSIsNull)
12486	DiagnoseAlwaysNonNullPointer(E: LHS.get(), NullType: RHSNullKind, IsEqual: IsEquality,
12487	Range: RHS.get()->getSourceRange());
12488	else
12489	DiagnoseAlwaysNonNullPointer(E: RHS.get(), NullType: LHSNullKind, IsEqual: IsEquality,
12490	Range: LHS.get()->getSourceRange());
12491	}
12492
12493	if (IsOrdered && LHSType->isFunctionPointerType() &&
12494	RHSType->isFunctionPointerType()) {
12495	// Valid unless a relational comparison of function pointers
12496	bool IsError = Opc == BO_Cmp;
12497	auto DiagID =
12498	IsError ? diag::err_typecheck_ordered_comparison_of_function_pointers
12499	: getLangOpts().CPlusPlus
12500	? diag::warn_typecheck_ordered_comparison_of_function_pointers
12501	: diag::ext_typecheck_ordered_comparison_of_function_pointers;
12502	Diag(Loc, DiagID) << LHSType << RHSType << LHS.get()->getSourceRange()
12503	<< RHS.get()->getSourceRange();
12504	if (IsError)
12505	return QualType();
12506	}
12507
12508	if ((LHSType->isIntegerType() && !LHSIsNull) ||
12509	(RHSType->isIntegerType() && !RHSIsNull)) {
12510	// Skip normal pointer conversion checks in this case; we have better
12511	// diagnostics for this below.
12512	} else if (getLangOpts().CPlusPlus) {
12513	// Equality comparison of a function pointer to a void pointer is invalid,
12514	// but we allow it as an extension.
12515	// FIXME: If we really want to allow this, should it be part of composite
12516	// pointer type computation so it works in conditionals too?
12517	if (!IsOrdered &&
12518	((LHSType->isFunctionPointerType() && RHSType->isVoidPointerType()) ||
12519	(RHSType->isFunctionPointerType() && LHSType->isVoidPointerType()))) {
12520	// This is a gcc extension compatibility comparison.
12521	// In a SFINAE context, we treat this as a hard error to maintain
12522	// conformance with the C++ standard.
12523	diagnoseFunctionPointerToVoidComparison(
12524	S&: *this, Loc, LHS, RHS, /*isError*/ IsError: (bool)isSFINAEContext());
12525
12526	if (isSFINAEContext())
12527	return QualType();
12528
12529	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_BitCast);
12530	return computeResultTy();
12531	}
12532
12533	// C++ [expr.eq]p2:
12534	// If at least one operand is a pointer [...] bring them to their
12535	// composite pointer type.
12536	// C++ [expr.spaceship]p6
12537	// If at least one of the operands is of pointer type, [...] bring them
12538	// to their composite pointer type.
12539	// C++ [expr.rel]p2:
12540	// If both operands are pointers, [...] bring them to their composite
12541	// pointer type.
12542	// For <=>, the only valid non-pointer types are arrays and functions, and
12543	// we already decayed those, so this is really the same as the relational
12544	// comparison rule.
12545	if ((int)LHSType->isPointerType() + (int)RHSType->isPointerType() >=
12546	(IsOrdered ? 2 : 1) &&
12547	(!LangOpts.ObjCAutoRefCount || !(LHSType->isObjCObjectPointerType() ||
12548	RHSType->isObjCObjectPointerType()))) {
12549	if (convertPointersToCompositeType(S&: *this, Loc, LHS, RHS))
12550	return QualType();
12551	return computeResultTy();
12552	}
12553	} else if (LHSType->isPointerType() &&
12554	RHSType->isPointerType()) { // C99 6.5.8p2
12555	// All of the following pointer-related warnings are GCC extensions, except
12556	// when handling null pointer constants.
12557	QualType LCanPointeeTy =
12558	LHSType->castAs<PointerType>()->getPointeeType().getCanonicalType();
12559	QualType RCanPointeeTy =
12560	RHSType->castAs<PointerType>()->getPointeeType().getCanonicalType();
12561
12562	// C99 6.5.9p2 and C99 6.5.8p2
12563	if (Context.typesAreCompatible(T1: LCanPointeeTy.getUnqualifiedType(),
12564	T2: RCanPointeeTy.getUnqualifiedType())) {
12565	if (IsRelational) {
12566	// Pointers both need to point to complete or incomplete types
12567	if ((LCanPointeeTy->isIncompleteType() !=
12568	RCanPointeeTy->isIncompleteType()) &&
12569	!getLangOpts().C11) {
12570	Diag(Loc, DiagID: diag::ext_typecheck_compare_complete_incomplete_pointers)
12571	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange()
12572	<< LHSType << RHSType << LCanPointeeTy->isIncompleteType()
12573	<< RCanPointeeTy->isIncompleteType();
12574	}
12575	}
12576	} else if (!IsRelational &&
12577	(LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) {
12578	// Valid unless comparison between non-null pointer and function pointer
12579	if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType())
12580	&& !LHSIsNull && !RHSIsNull)
12581	diagnoseFunctionPointerToVoidComparison(S&: *this, Loc, LHS, RHS,
12582	/*isError*/IsError: false);
12583	} else {
12584	// Invalid
12585	diagnoseDistinctPointerComparison(S&: *this, Loc, LHS, RHS, /*isError*/IsError: false);
12586	}
12587	if (LCanPointeeTy != RCanPointeeTy) {
12588	// Treat NULL constant as a special case in OpenCL.
12589	if (getLangOpts().OpenCL && !LHSIsNull && !RHSIsNull) {
12590	if (!LCanPointeeTy.isAddressSpaceOverlapping(T: RCanPointeeTy,
12591	Ctx: getASTContext())) {
12592	Diag(Loc,
12593	DiagID: diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
12594	<< LHSType << RHSType << 0 /* comparison */
12595	<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
12596	}
12597	}
12598	LangAS AddrSpaceL = LCanPointeeTy.getAddressSpace();
12599	LangAS AddrSpaceR = RCanPointeeTy.getAddressSpace();
12600	CastKind Kind = AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion
12601	: CK_BitCast;
12602
12603	const FunctionType *LFn = LCanPointeeTy->getAs<FunctionType>();
12604	const FunctionType *RFn = RCanPointeeTy->getAs<FunctionType>();
12605	bool LHSHasCFIUncheckedCallee = LFn && LFn->getCFIUncheckedCalleeAttr();
12606	bool RHSHasCFIUncheckedCallee = RFn && RFn->getCFIUncheckedCalleeAttr();
12607	bool ChangingCFIUncheckedCallee =
12608	LHSHasCFIUncheckedCallee != RHSHasCFIUncheckedCallee;
12609
12610	if (LHSIsNull && !RHSIsNull)
12611	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: Kind);
12612	else if (!ChangingCFIUncheckedCallee)
12613	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: Kind);
12614	}
12615	return computeResultTy();
12616	}
12617
12618
12619	// C++ [expr.eq]p4:
12620	// Two operands of type std::nullptr_t or one operand of type
12621	// std::nullptr_t and the other a null pointer constant compare
12622	// equal.
12623	// C23 6.5.9p5:
12624	// If both operands have type nullptr_t or one operand has type nullptr_t
12625	// and the other is a null pointer constant, they compare equal if the
12626	// former is a null pointer.
12627	if (!IsOrdered && LHSIsNull && RHSIsNull) {
12628	if (LHSType->isNullPtrType()) {
12629	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
12630	return computeResultTy();
12631	}
12632	if (RHSType->isNullPtrType()) {
12633	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
12634	return computeResultTy();
12635	}
12636	}
12637
12638	if (!getLangOpts().CPlusPlus && !IsOrdered && (LHSIsNull || RHSIsNull)) {
12639	// C23 6.5.9p6:
12640	// Otherwise, at least one operand is a pointer. If one is a pointer and
12641	// the other is a null pointer constant or has type nullptr_t, they
12642	// compare equal
12643	if (LHSIsNull && RHSType->isPointerType()) {
12644	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
12645	return computeResultTy();
12646	}
12647	if (RHSIsNull && LHSType->isPointerType()) {
12648	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
12649	return computeResultTy();
12650	}
12651	}
12652
12653	// Comparison of Objective-C pointers and block pointers against nullptr_t.
12654	// These aren't covered by the composite pointer type rules.
12655	if (!IsOrdered && RHSType->isNullPtrType() &&
12656	(LHSType->isObjCObjectPointerType() || LHSType->isBlockPointerType())) {
12657	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
12658	return computeResultTy();
12659	}
12660	if (!IsOrdered && LHSType->isNullPtrType() &&
12661	(RHSType->isObjCObjectPointerType() || RHSType->isBlockPointerType())) {
12662	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
12663	return computeResultTy();
12664	}
12665
12666	if (getLangOpts().CPlusPlus) {
12667	if (IsRelational &&
12668	((LHSType->isNullPtrType() && RHSType->isPointerType()) ||
12669	(RHSType->isNullPtrType() && LHSType->isPointerType()))) {
12670	// HACK: Relational comparison of nullptr_t against a pointer type is
12671	// invalid per DR583, but we allow it within std::less<> and friends,
12672	// since otherwise common uses of it break.
12673	// FIXME: Consider removing this hack once LWG fixes std::less<> and
12674	// friends to have std::nullptr_t overload candidates.
12675	DeclContext *DC = CurContext;
12676	if (isa<FunctionDecl>(Val: DC))
12677	DC = DC->getParent();
12678	if (auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(Val: DC)) {
12679	if (CTSD->isInStdNamespace() &&
12680	llvm::StringSwitch<bool>(CTSD->getName())
12681	.Cases(S0: "less", S1: "less_equal", S2: "greater", S3: "greater_equal", Value: true)
12682	.Default(Value: false)) {
12683	if (RHSType->isNullPtrType())
12684	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
12685	else
12686	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
12687	return computeResultTy();
12688	}
12689	}
12690	}
12691
12692	// C++ [expr.eq]p2:
12693	// If at least one operand is a pointer to member, [...] bring them to
12694	// their composite pointer type.
12695	if (!IsOrdered &&
12696	(LHSType->isMemberPointerType() || RHSType->isMemberPointerType())) {
12697	if (convertPointersToCompositeType(S&: *this, Loc, LHS, RHS))
12698	return QualType();
12699	else
12700	return computeResultTy();
12701	}
12702	}
12703
12704	// Handle block pointer types.
12705	if (!IsOrdered && LHSType->isBlockPointerType() &&
12706	RHSType->isBlockPointerType()) {
12707	QualType lpointee = LHSType->castAs<BlockPointerType>()->getPointeeType();
12708	QualType rpointee = RHSType->castAs<BlockPointerType>()->getPointeeType();
12709
12710	if (!LHSIsNull && !RHSIsNull &&
12711	!Context.typesAreCompatible(T1: lpointee, T2: rpointee)) {
12712	Diag(Loc, DiagID: diag::err_typecheck_comparison_of_distinct_blocks)
12713	<< LHSType << RHSType << LHS.get()->getSourceRange()
12714	<< RHS.get()->getSourceRange();
12715	}
12716	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_BitCast);
12717	return computeResultTy();
12718	}
12719
12720	// Allow block pointers to be compared with null pointer constants.
12721	if (!IsOrdered
12722	&& ((LHSType->isBlockPointerType() && RHSType->isPointerType())
12723	|| (LHSType->isPointerType() && RHSType->isBlockPointerType()))) {
12724	if (!LHSIsNull && !RHSIsNull) {
12725	if (!((RHSType->isPointerType() && RHSType->castAs<PointerType>()
12726	->getPointeeType()->isVoidType())
12727	|| (LHSType->isPointerType() && LHSType->castAs<PointerType>()
12728	->getPointeeType()->isVoidType())))
12729	Diag(Loc, DiagID: diag::err_typecheck_comparison_of_distinct_blocks)
12730	<< LHSType << RHSType << LHS.get()->getSourceRange()
12731	<< RHS.get()->getSourceRange();
12732	}
12733	if (LHSIsNull && !RHSIsNull)
12734	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType,
12735	CK: RHSType->isPointerType() ? CK_BitCast
12736	: CK_AnyPointerToBlockPointerCast);
12737	else
12738	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType,
12739	CK: LHSType->isPointerType() ? CK_BitCast
12740	: CK_AnyPointerToBlockPointerCast);
12741	return computeResultTy();
12742	}
12743
12744	if (LHSType->isObjCObjectPointerType() ||
12745	RHSType->isObjCObjectPointerType()) {
12746	const PointerType *LPT = LHSType->getAs<PointerType>();
12747	const PointerType *RPT = RHSType->getAs<PointerType>();
12748	if (LPT || RPT) {
12749	bool LPtrToVoid = LPT ? LPT->getPointeeType()->isVoidType() : false;
12750	bool RPtrToVoid = RPT ? RPT->getPointeeType()->isVoidType() : false;
12751
12752	if (!LPtrToVoid && !RPtrToVoid &&
12753	!Context.typesAreCompatible(T1: LHSType, T2: RHSType)) {
12754	diagnoseDistinctPointerComparison(S&: *this, Loc, LHS, RHS,
12755	/*isError*/IsError: false);
12756	}
12757	// FIXME: If LPtrToVoid, we should presumably convert the LHS rather than
12758	// the RHS, but we have test coverage for this behavior.
12759	// FIXME: Consider using convertPointersToCompositeType in C++.
12760	if (LHSIsNull && !RHSIsNull) {
12761	Expr *E = LHS.get();
12762	if (getLangOpts().ObjCAutoRefCount)
12763	ObjC().CheckObjCConversion(castRange: SourceRange(), castType: RHSType, op&: E,
12764	CCK: CheckedConversionKind::Implicit);
12765	LHS = ImpCastExprToType(E, Type: RHSType,
12766	CK: RPT ? CK_BitCast :CK_CPointerToObjCPointerCast);
12767	}
12768	else {
12769	Expr *E = RHS.get();
12770	if (getLangOpts().ObjCAutoRefCount)
12771	ObjC().CheckObjCConversion(castRange: SourceRange(), castType: LHSType, op&: E,
12772	CCK: CheckedConversionKind::Implicit,
12773	/*Diagnose=*/true,
12774	/*DiagnoseCFAudited=*/false, Opc);
12775	RHS = ImpCastExprToType(E, Type: LHSType,
12776	CK: LPT ? CK_BitCast :CK_CPointerToObjCPointerCast);
12777	}
12778	return computeResultTy();
12779	}
12780	if (LHSType->isObjCObjectPointerType() &&
12781	RHSType->isObjCObjectPointerType()) {
12782	if (!Context.areComparableObjCPointerTypes(LHS: LHSType, RHS: RHSType))
12783	diagnoseDistinctPointerComparison(S&: *this, Loc, LHS, RHS,
12784	/*isError*/IsError: false);
12785	if (isObjCObjectLiteral(E&: LHS) || isObjCObjectLiteral(E&: RHS))
12786	diagnoseObjCLiteralComparison(S&: *this, Loc, LHS, RHS, Opc);
12787
12788	if (LHSIsNull && !RHSIsNull)
12789	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_BitCast);
12790	else
12791	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_BitCast);
12792	return computeResultTy();
12793	}
12794
12795	if (!IsOrdered && LHSType->isBlockPointerType() &&
12796	RHSType->isBlockCompatibleObjCPointerType(ctx&: Context)) {
12797	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType,
12798	CK: CK_BlockPointerToObjCPointerCast);
12799	return computeResultTy();
12800	} else if (!IsOrdered &&
12801	LHSType->isBlockCompatibleObjCPointerType(ctx&: Context) &&
12802	RHSType->isBlockPointerType()) {
12803	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType,
12804	CK: CK_BlockPointerToObjCPointerCast);
12805	return computeResultTy();
12806	}
12807	}
12808	if ((LHSType->isAnyPointerType() && RHSType->isIntegerType()) ||
12809	(LHSType->isIntegerType() && RHSType->isAnyPointerType())) {
12810	unsigned DiagID = 0;
12811	bool isError = false;
12812	if (LangOpts.DebuggerSupport) {
12813	// Under a debugger, allow the comparison of pointers to integers,
12814	// since users tend to want to compare addresses.
12815	} else if ((LHSIsNull && LHSType->isIntegerType()) ||
12816	(RHSIsNull && RHSType->isIntegerType())) {
12817	if (IsOrdered) {
12818	isError = getLangOpts().CPlusPlus;
12819	DiagID =
12820	isError ? diag::err_typecheck_ordered_comparison_of_pointer_and_zero
12821	: diag::ext_typecheck_ordered_comparison_of_pointer_and_zero;
12822	}
12823	} else if (getLangOpts().CPlusPlus) {
12824	DiagID = diag::err_typecheck_comparison_of_pointer_integer;
12825	isError = true;
12826	} else if (IsOrdered)
12827	DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer;
12828	else
12829	DiagID = diag::ext_typecheck_comparison_of_pointer_integer;
12830
12831	if (DiagID) {
12832	Diag(Loc, DiagID)
12833	<< LHSType << RHSType << LHS.get()->getSourceRange()
12834	<< RHS.get()->getSourceRange();
12835	if (isError)
12836	return QualType();
12837	}
12838
12839	if (LHSType->isIntegerType())
12840	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType,
12841	CK: LHSIsNull ? CK_NullToPointer : CK_IntegralToPointer);
12842	else
12843	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType,
12844	CK: RHSIsNull ? CK_NullToPointer : CK_IntegralToPointer);
12845	return computeResultTy();
12846	}
12847
12848	// Handle block pointers.
12849	if (!IsOrdered && RHSIsNull
12850	&& LHSType->isBlockPointerType() && RHSType->isIntegerType()) {
12851	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
12852	return computeResultTy();
12853	}
12854	if (!IsOrdered && LHSIsNull
12855	&& LHSType->isIntegerType() && RHSType->isBlockPointerType()) {
12856	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
12857	return computeResultTy();
12858	}
12859
12860	if (getLangOpts().getOpenCLCompatibleVersion() >= 200) {
12861	if (LHSType->isClkEventT() && RHSType->isClkEventT()) {
12862	return computeResultTy();
12863	}
12864
12865	if (LHSType->isQueueT() && RHSType->isQueueT()) {
12866	return computeResultTy();
12867	}
12868
12869	if (LHSIsNull && RHSType->isQueueT()) {
12870	LHS = ImpCastExprToType(E: LHS.get(), Type: RHSType, CK: CK_NullToPointer);
12871	return computeResultTy();
12872	}
12873
12874	if (LHSType->isQueueT() && RHSIsNull) {
12875	RHS = ImpCastExprToType(E: RHS.get(), Type: LHSType, CK: CK_NullToPointer);
12876	return computeResultTy();
12877	}
12878	}
12879
12880	return InvalidOperands(Loc, LHS, RHS);
12881	}
12882
12883	QualType Sema::GetSignedVectorType(QualType V) {
12884	const VectorType *VTy = V->castAs<VectorType>();
12885	unsigned TypeSize = Context.getTypeSize(T: VTy->getElementType());
12886
12887	if (isa<ExtVectorType>(Val: VTy)) {
12888	if (VTy->isExtVectorBoolType())
12889	return Context.getExtVectorType(VectorType: Context.BoolTy, NumElts: VTy->getNumElements());
12890	if (TypeSize == Context.getTypeSize(T: Context.CharTy))
12891	return Context.getExtVectorType(VectorType: Context.CharTy, NumElts: VTy->getNumElements());
12892	if (TypeSize == Context.getTypeSize(T: Context.ShortTy))
12893	return Context.getExtVectorType(VectorType: Context.ShortTy, NumElts: VTy->getNumElements());
12894	if (TypeSize == Context.getTypeSize(T: Context.IntTy))
12895	return Context.getExtVectorType(VectorType: Context.IntTy, NumElts: VTy->getNumElements());
12896	if (TypeSize == Context.getTypeSize(T: Context.Int128Ty))
12897	return Context.getExtVectorType(VectorType: Context.Int128Ty, NumElts: VTy->getNumElements());
12898	if (TypeSize == Context.getTypeSize(T: Context.LongTy))
12899	return Context.getExtVectorType(VectorType: Context.LongTy, NumElts: VTy->getNumElements());
12900	assert(TypeSize == Context.getTypeSize(Context.LongLongTy) &&
12901	"Unhandled vector element size in vector compare");
12902	return Context.getExtVectorType(VectorType: Context.LongLongTy, NumElts: VTy->getNumElements());
12903	}
12904
12905	if (TypeSize == Context.getTypeSize(T: Context.Int128Ty))
12906	return Context.getVectorType(VectorType: Context.Int128Ty, NumElts: VTy->getNumElements(),
12907	VecKind: VectorKind::Generic);
12908	if (TypeSize == Context.getTypeSize(T: Context.LongLongTy))
12909	return Context.getVectorType(VectorType: Context.LongLongTy, NumElts: VTy->getNumElements(),
12910	VecKind: VectorKind::Generic);
12911	if (TypeSize == Context.getTypeSize(T: Context.LongTy))
12912	return Context.getVectorType(VectorType: Context.LongTy, NumElts: VTy->getNumElements(),
12913	VecKind: VectorKind::Generic);
12914	if (TypeSize == Context.getTypeSize(T: Context.IntTy))
12915	return Context.getVectorType(VectorType: Context.IntTy, NumElts: VTy->getNumElements(),
12916	VecKind: VectorKind::Generic);
12917	if (TypeSize == Context.getTypeSize(T: Context.ShortTy))
12918	return Context.getVectorType(VectorType: Context.ShortTy, NumElts: VTy->getNumElements(),
12919	VecKind: VectorKind::Generic);
12920	assert(TypeSize == Context.getTypeSize(Context.CharTy) &&
12921	"Unhandled vector element size in vector compare");
12922	return Context.getVectorType(VectorType: Context.CharTy, NumElts: VTy->getNumElements(),
12923	VecKind: VectorKind::Generic);
12924	}
12925
12926	QualType Sema::GetSignedSizelessVectorType(QualType V) {
12927	const BuiltinType *VTy = V->castAs<BuiltinType>();
12928	assert(VTy->isSizelessBuiltinType() && "expected sizeless type");
12929
12930	const QualType ETy = V->getSveEltType(Ctx: Context);
12931	const auto TypeSize = Context.getTypeSize(T: ETy);
12932
12933	const QualType IntTy = Context.getIntTypeForBitwidth(DestWidth: TypeSize, Signed: true);
12934	const llvm::ElementCount VecSize = Context.getBuiltinVectorTypeInfo(VecTy: VTy).EC;
12935	return Context.getScalableVectorType(EltTy: IntTy, NumElts: VecSize.getKnownMinValue());
12936	}
12937
12938	QualType Sema::CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS,
12939	SourceLocation Loc,
12940	BinaryOperatorKind Opc) {
12941	if (Opc == BO_Cmp) {
12942	Diag(Loc, DiagID: diag::err_three_way_vector_comparison);
12943	return QualType();
12944	}
12945
12946	// Check to make sure we're operating on vectors of the same type and width,
12947	// Allowing one side to be a scalar of element type.
12948	QualType vType =
12949	CheckVectorOperands(LHS, RHS, Loc, /*isCompAssign*/ IsCompAssign: false,
12950	/*AllowBothBool*/ true,
12951	/*AllowBoolConversions*/ getLangOpts().ZVector,
12952	/*AllowBooleanOperation*/ AllowBoolOperation: true,
12953	/*ReportInvalid*/ true);
12954	if (vType.isNull())
12955	return vType;
12956
12957	QualType LHSType = LHS.get()->getType();
12958
12959	// Determine the return type of a vector compare. By default clang will return
12960	// a scalar for all vector compares except vector bool and vector pixel.
12961	// With the gcc compiler we will always return a vector type and with the xl
12962	// compiler we will always return a scalar type. This switch allows choosing
12963	// which behavior is prefered.
12964	if (getLangOpts().AltiVec) {
12965	switch (getLangOpts().getAltivecSrcCompat()) {
12966	case LangOptions::AltivecSrcCompatKind::Mixed:
12967	// If AltiVec, the comparison results in a numeric type, i.e.
12968	// bool for C++, int for C
12969	if (vType->castAs<VectorType>()->getVectorKind() ==
12970	VectorKind::AltiVecVector)
12971	return Context.getLogicalOperationType();
12972	else
12973	Diag(Loc, DiagID: diag::warn_deprecated_altivec_src_compat);
12974	break;
12975	case LangOptions::AltivecSrcCompatKind::GCC:
12976	// For GCC we always return the vector type.
12977	break;
12978	case LangOptions::AltivecSrcCompatKind::XL:
12979	return Context.getLogicalOperationType();
12980	break;
12981	}
12982	}
12983
12984	// For non-floating point types, check for self-comparisons of the form
12985	// x == x, x != x, x < x, etc. These always evaluate to a constant, and
12986	// often indicate logic errors in the program.
12987	diagnoseTautologicalComparison(S&: *this, Loc, LHS: LHS.get(), RHS: RHS.get(), Opc);
12988
12989	// Check for comparisons of floating point operands using != and ==.
12990	if (LHSType->hasFloatingRepresentation()) {
12991	assert(RHS.get()->getType()->hasFloatingRepresentation());
12992	CheckFloatComparison(Loc, LHS: LHS.get(), RHS: RHS.get(), Opcode: Opc);
12993	}
12994
12995	// Return a signed type for the vector.
12996	return GetSignedVectorType(V: vType);
12997	}
12998
12999	QualType Sema::CheckSizelessVectorCompareOperands(ExprResult &LHS,
13000	ExprResult &RHS,
13001	SourceLocation Loc,
13002	BinaryOperatorKind Opc) {
13003	if (Opc == BO_Cmp) {
13004	Diag(Loc, DiagID: diag::err_three_way_vector_comparison);
13005	return QualType();
13006	}
13007
13008	// Check to make sure we're operating on vectors of the same type and width,
13009	// Allowing one side to be a scalar of element type.
13010	QualType vType = CheckSizelessVectorOperands(
13011	LHS, RHS, Loc, /*isCompAssign*/ IsCompAssign: false, OperationKind: ArithConvKind::Comparison);
13012
13013	if (vType.isNull())
13014	return vType;
13015
13016	QualType LHSType = LHS.get()->getType();
13017
13018	// For non-floating point types, check for self-comparisons of the form
13019	// x == x, x != x, x < x, etc. These always evaluate to a constant, and
13020	// often indicate logic errors in the program.
13021	diagnoseTautologicalComparison(S&: *this, Loc, LHS: LHS.get(), RHS: RHS.get(), Opc);
13022
13023	// Check for comparisons of floating point operands using != and ==.
13024	if (LHSType->hasFloatingRepresentation()) {
13025	assert(RHS.get()->getType()->hasFloatingRepresentation());
13026	CheckFloatComparison(Loc, LHS: LHS.get(), RHS: RHS.get(), Opcode: Opc);
13027	}
13028
13029	const BuiltinType *LHSBuiltinTy = LHSType->getAs<BuiltinType>();
13030	const BuiltinType *RHSBuiltinTy = RHS.get()->getType()->getAs<BuiltinType>();
13031
13032	if (LHSBuiltinTy && RHSBuiltinTy && LHSBuiltinTy->isSVEBool() &&
13033	RHSBuiltinTy->isSVEBool())
13034	return LHSType;
13035
13036	// Return a signed type for the vector.
13037	return GetSignedSizelessVectorType(V: vType);
13038	}
13039
13040	static void diagnoseXorMisusedAsPow(Sema &S, const ExprResult &XorLHS,
13041	const ExprResult &XorRHS,
13042	const SourceLocation Loc) {
13043	// Do not diagnose macros.
13044	if (Loc.isMacroID())
13045	return;
13046
13047	// Do not diagnose if both LHS and RHS are macros.
13048	if (XorLHS.get()->getExprLoc().isMacroID() &&
13049	XorRHS.get()->getExprLoc().isMacroID())
13050	return;
13051
13052	bool Negative = false;
13053	bool ExplicitPlus = false;
13054	const auto *LHSInt = dyn_cast<IntegerLiteral>(Val: XorLHS.get());
13055	const auto *RHSInt = dyn_cast<IntegerLiteral>(Val: XorRHS.get());
13056
13057	if (!LHSInt)
13058	return;
13059	if (!RHSInt) {
13060	// Check negative literals.
13061	if (const auto *UO = dyn_cast<UnaryOperator>(Val: XorRHS.get())) {
13062	UnaryOperatorKind Opc = UO->getOpcode();
13063	if (Opc != UO_Minus && Opc != UO_Plus)
13064	return;
13065	RHSInt = dyn_cast<IntegerLiteral>(Val: UO->getSubExpr());
13066	if (!RHSInt)
13067	return;
13068	Negative = (Opc == UO_Minus);
13069	ExplicitPlus = !Negative;
13070	} else {
13071	return;
13072	}
13073	}
13074
13075	const llvm::APInt &LeftSideValue = LHSInt->getValue();
13076	llvm::APInt RightSideValue = RHSInt->getValue();
13077	if (LeftSideValue != 2 && LeftSideValue != 10)
13078	return;
13079
13080	if (LeftSideValue.getBitWidth() != RightSideValue.getBitWidth())
13081	return;
13082
13083	CharSourceRange ExprRange = CharSourceRange::getCharRange(
13084	B: LHSInt->getBeginLoc(), E: S.getLocForEndOfToken(Loc: RHSInt->getLocation()));
13085	llvm::StringRef ExprStr =
13086	Lexer::getSourceText(Range: ExprRange, SM: S.getSourceManager(), LangOpts: S.getLangOpts());
13087
13088	CharSourceRange XorRange =
13089	CharSourceRange::getCharRange(B: Loc, E: S.getLocForEndOfToken(Loc));
13090	llvm::StringRef XorStr =
13091	Lexer::getSourceText(Range: XorRange, SM: S.getSourceManager(), LangOpts: S.getLangOpts());
13092	// Do not diagnose if xor keyword/macro is used.
13093	if (XorStr == "xor")
13094	return;
13095
13096	std::string LHSStr = std::string(Lexer::getSourceText(
13097	Range: CharSourceRange::getTokenRange(R: LHSInt->getSourceRange()),
13098	SM: S.getSourceManager(), LangOpts: S.getLangOpts()));
13099	std::string RHSStr = std::string(Lexer::getSourceText(
13100	Range: CharSourceRange::getTokenRange(R: RHSInt->getSourceRange()),
13101	SM: S.getSourceManager(), LangOpts: S.getLangOpts()));
13102
13103	if (Negative) {
13104	RightSideValue = -RightSideValue;
13105	RHSStr = "-" + RHSStr;
13106	} else if (ExplicitPlus) {
13107	RHSStr = "+" + RHSStr;
13108	}
13109
13110	StringRef LHSStrRef = LHSStr;
13111	StringRef RHSStrRef = RHSStr;
13112	// Do not diagnose literals with digit separators, binary, hexadecimal, octal
13113	// literals.
13114	if (LHSStrRef.starts_with(Prefix: "0b") || LHSStrRef.starts_with(Prefix: "0B") ||
13115	RHSStrRef.starts_with(Prefix: "0b") || RHSStrRef.starts_with(Prefix: "0B") ||
13116	LHSStrRef.starts_with(Prefix: "0x") || LHSStrRef.starts_with(Prefix: "0X") ||
13117	RHSStrRef.starts_with(Prefix: "0x") || RHSStrRef.starts_with(Prefix: "0X") ||
13118	(LHSStrRef.size() > 1 && LHSStrRef.starts_with(Prefix: "0")) ||
13119	(RHSStrRef.size() > 1 && RHSStrRef.starts_with(Prefix: "0")) ||
13120	LHSStrRef.contains(C: '\'') || RHSStrRef.contains(C: '\''))
13121	return;
13122
13123	bool SuggestXor =
13124	S.getLangOpts().CPlusPlus || S.getPreprocessor().isMacroDefined(Id: "xor");
13125	const llvm::APInt XorValue = LeftSideValue ^ RightSideValue;
13126	int64_t RightSideIntValue = RightSideValue.getSExtValue();
13127	if (LeftSideValue == 2 && RightSideIntValue >= 0) {
13128	std::string SuggestedExpr = "1 << " + RHSStr;
13129	bool Overflow = false;
13130	llvm::APInt One = (LeftSideValue - 1);
13131	llvm::APInt PowValue = One.sshl_ov(Amt: RightSideValue, Overflow);
13132	if (Overflow) {
13133	if (RightSideIntValue < 64)
13134	S.Diag(Loc, DiagID: diag::warn_xor_used_as_pow_base)
13135	<< ExprStr << toString(I: XorValue, Radix: 10, Signed: true) << ("1LL << " + RHSStr)
13136	<< FixItHint::CreateReplacement(RemoveRange: ExprRange, Code: "1LL << " + RHSStr);
13137	else if (RightSideIntValue == 64)
13138	S.Diag(Loc, DiagID: diag::warn_xor_used_as_pow)
13139	<< ExprStr << toString(I: XorValue, Radix: 10, Signed: true);
13140	else
13141	return;
13142	} else {
13143	S.Diag(Loc, DiagID: diag::warn_xor_used_as_pow_base_extra)
13144	<< ExprStr << toString(I: XorValue, Radix: 10, Signed: true) << SuggestedExpr
13145	<< toString(I: PowValue, Radix: 10, Signed: true)
13146	<< FixItHint::CreateReplacement(
13147	RemoveRange: ExprRange, Code: (RightSideIntValue == 0) ? "1" : SuggestedExpr);
13148	}
13149
13150	S.Diag(Loc, DiagID: diag::note_xor_used_as_pow_silence)
13151	<< ("0x2 ^ " + RHSStr) << SuggestXor;
13152	} else if (LeftSideValue == 10) {
13153	std::string SuggestedValue = "1e" + std::to_string(val: RightSideIntValue);
13154	S.Diag(Loc, DiagID: diag::warn_xor_used_as_pow_base)
13155	<< ExprStr << toString(I: XorValue, Radix: 10, Signed: true) << SuggestedValue
13156	<< FixItHint::CreateReplacement(RemoveRange: ExprRange, Code: SuggestedValue);
13157	S.Diag(Loc, DiagID: diag::note_xor_used_as_pow_silence)
13158	<< ("0xA ^ " + RHSStr) << SuggestXor;
13159	}
13160	}
13161
13162	QualType Sema::CheckVectorLogicalOperands(ExprResult &LHS, ExprResult &RHS,
13163	SourceLocation Loc,
13164	BinaryOperatorKind Opc) {
13165	// Ensure that either both operands are of the same vector type, or
13166	// one operand is of a vector type and the other is of its element type.
13167	QualType vType = CheckVectorOperands(LHS, RHS, Loc, IsCompAssign: false,
13168	/*AllowBothBool*/ true,
13169	/*AllowBoolConversions*/ false,
13170	/*AllowBooleanOperation*/ AllowBoolOperation: false,
13171	/*ReportInvalid*/ false);
13172	if (vType.isNull())
13173	return InvalidOperands(Loc, LHS, RHS);
13174	if (getLangOpts().OpenCL &&
13175	getLangOpts().getOpenCLCompatibleVersion() < 120 &&
13176	vType->hasFloatingRepresentation())
13177	return InvalidOperands(Loc, LHS, RHS);
13178	// FIXME: The check for C++ here is for GCC compatibility. GCC rejects the
13179	// usage of the logical operators && and || with vectors in C. This
13180	// check could be notionally dropped.
13181	if (!getLangOpts().CPlusPlus &&
13182	!(isa<ExtVectorType>(Val: vType->getAs<VectorType>())))
13183	return InvalidLogicalVectorOperands(Loc, LHS, RHS);
13184	// Beginning with HLSL 2021, HLSL disallows logical operators on vector
13185	// operands and instead requires the use of the `and`, `or`, `any`, `all`, and
13186	// `select` functions.
13187	if (getLangOpts().HLSL &&
13188	getLangOpts().getHLSLVersion() >= LangOptionsBase::HLSL_2021) {
13189	(void)InvalidOperands(Loc, LHS, RHS);
13190	HLSL().emitLogicalOperatorFixIt(LHS: LHS.get(), RHS: RHS.get(), Opc);
13191	return QualType();
13192	}
13193
13194	return GetSignedVectorType(V: LHS.get()->getType());
13195	}
13196
13197	QualType Sema::CheckMatrixElementwiseOperands(ExprResult &LHS, ExprResult &RHS,
13198	SourceLocation Loc,
13199	bool IsCompAssign) {
13200	if (!IsCompAssign) {
13201	LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
13202	if (LHS.isInvalid())
13203	return QualType();
13204	}
13205	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
13206	if (RHS.isInvalid())
13207	return QualType();
13208
13209	// For conversion purposes, we ignore any qualifiers.
13210	// For example, "const float" and "float" are equivalent.
13211	QualType LHSType = LHS.get()->getType().getUnqualifiedType();
13212	QualType RHSType = RHS.get()->getType().getUnqualifiedType();
13213
13214	const MatrixType *LHSMatType = LHSType->getAs<MatrixType>();
13215	const MatrixType *RHSMatType = RHSType->getAs<MatrixType>();
13216	assert((LHSMatType || RHSMatType) && "At least one operand must be a matrix");
13217
13218	if (Context.hasSameType(T1: LHSType, T2: RHSType))
13219	return Context.getCommonSugaredType(X: LHSType, Y: RHSType);
13220
13221	// Type conversion may change LHS/RHS. Keep copies to the original results, in
13222	// case we have to return InvalidOperands.
13223	ExprResult OriginalLHS = LHS;
13224	ExprResult OriginalRHS = RHS;
13225	if (LHSMatType && !RHSMatType) {
13226	RHS = tryConvertExprToType(E: RHS.get(), Ty: LHSMatType->getElementType());
13227	if (!RHS.isInvalid())
13228	return LHSType;
13229
13230	return InvalidOperands(Loc, LHS&: OriginalLHS, RHS&: OriginalRHS);
13231	}
13232
13233	if (!LHSMatType && RHSMatType) {
13234	LHS = tryConvertExprToType(E: LHS.get(), Ty: RHSMatType->getElementType());
13235	if (!LHS.isInvalid())
13236	return RHSType;
13237	return InvalidOperands(Loc, LHS&: OriginalLHS, RHS&: OriginalRHS);
13238	}
13239
13240	return InvalidOperands(Loc, LHS, RHS);
13241	}
13242
13243	QualType Sema::CheckMatrixMultiplyOperands(ExprResult &LHS, ExprResult &RHS,
13244	SourceLocation Loc,
13245	bool IsCompAssign) {
13246	if (!IsCompAssign) {
13247	LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
13248	if (LHS.isInvalid())
13249	return QualType();
13250	}
13251	RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
13252	if (RHS.isInvalid())
13253	return QualType();
13254
13255	auto *LHSMatType = LHS.get()->getType()->getAs<ConstantMatrixType>();
13256	auto *RHSMatType = RHS.get()->getType()->getAs<ConstantMatrixType>();
13257	assert((LHSMatType || RHSMatType) && "At least one operand must be a matrix");
13258
13259	if (LHSMatType && RHSMatType) {
13260	if (LHSMatType->getNumColumns() != RHSMatType->getNumRows())
13261	return InvalidOperands(Loc, LHS, RHS);
13262
13263	if (Context.hasSameType(T1: LHSMatType, T2: RHSMatType))
13264	return Context.getCommonSugaredType(
13265	X: LHS.get()->getType().getUnqualifiedType(),
13266	Y: RHS.get()->getType().getUnqualifiedType());
13267
13268	QualType LHSELTy = LHSMatType->getElementType(),
13269	RHSELTy = RHSMatType->getElementType();
13270	if (!Context.hasSameType(T1: LHSELTy, T2: RHSELTy))
13271	return InvalidOperands(Loc, LHS, RHS);
13272
13273	return Context.getConstantMatrixType(
13274	ElementType: Context.getCommonSugaredType(X: LHSELTy, Y: RHSELTy),
13275	NumRows: LHSMatType->getNumRows(), NumColumns: RHSMatType->getNumColumns());
13276	}
13277	return CheckMatrixElementwiseOperands(LHS, RHS, Loc, IsCompAssign);
13278	}
13279
13280	static bool isLegalBoolVectorBinaryOp(BinaryOperatorKind Opc) {
13281	switch (Opc) {
13282	default:
13283	return false;
13284	case BO_And:
13285	case BO_AndAssign:
13286	case BO_Or:
13287	case BO_OrAssign:
13288	case BO_Xor:
13289	case BO_XorAssign:
13290	return true;
13291	}
13292	}
13293
13294	inline QualType Sema::CheckBitwiseOperands(ExprResult &LHS, ExprResult &RHS,
13295	SourceLocation Loc,
13296	BinaryOperatorKind Opc) {
13297	checkArithmeticNull(S&: *this, LHS, RHS, Loc, /*IsCompare=*/false);
13298
13299	bool IsCompAssign =
13300	Opc == BO_AndAssign || Opc == BO_OrAssign || Opc == BO_XorAssign;
13301
13302	bool LegalBoolVecOperator = isLegalBoolVectorBinaryOp(Opc);
13303
13304	if (LHS.get()->getType()->isVectorType() ||
13305	RHS.get()->getType()->isVectorType()) {
13306	if (LHS.get()->getType()->hasIntegerRepresentation() &&
13307	RHS.get()->getType()->hasIntegerRepresentation())
13308	return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
13309	/*AllowBothBool*/ true,
13310	/*AllowBoolConversions*/ getLangOpts().ZVector,
13311	/*AllowBooleanOperation*/ AllowBoolOperation: LegalBoolVecOperator,
13312	/*ReportInvalid*/ true);
13313	return InvalidOperands(Loc, LHS, RHS);
13314	}
13315
13316	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
13317	RHS.get()->getType()->isSveVLSBuiltinType()) {
13318	if (LHS.get()->getType()->hasIntegerRepresentation() &&
13319	RHS.get()->getType()->hasIntegerRepresentation())
13320	return CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign,
13321	OperationKind: ArithConvKind::BitwiseOp);
13322	return InvalidOperands(Loc, LHS, RHS);
13323	}
13324
13325	if (LHS.get()->getType()->isSveVLSBuiltinType() ||
13326	RHS.get()->getType()->isSveVLSBuiltinType()) {
13327	if (LHS.get()->getType()->hasIntegerRepresentation() &&
13328	RHS.get()->getType()->hasIntegerRepresentation())
13329	return CheckSizelessVectorOperands(LHS, RHS, Loc, IsCompAssign,
13330	OperationKind: ArithConvKind::BitwiseOp);
13331	return InvalidOperands(Loc, LHS, RHS);
13332	}
13333
13334	if (Opc == BO_And)
13335	diagnoseLogicalNotOnLHSofCheck(S&: *this, LHS, RHS, Loc, Opc);
13336
13337	if (LHS.get()->getType()->hasFloatingRepresentation() ||
13338	RHS.get()->getType()->hasFloatingRepresentation())
13339	return InvalidOperands(Loc, LHS, RHS);
13340
13341	ExprResult LHSResult = LHS, RHSResult = RHS;
13342	QualType compType = UsualArithmeticConversions(
13343	LHS&: LHSResult, RHS&: RHSResult, Loc,
13344	ACK: IsCompAssign ? ArithConvKind::CompAssign : ArithConvKind::BitwiseOp);
13345	if (LHSResult.isInvalid() || RHSResult.isInvalid())
13346	return QualType();
13347	LHS = LHSResult.get();
13348	RHS = RHSResult.get();
13349
13350	if (Opc == BO_Xor)
13351	diagnoseXorMisusedAsPow(S&: *this, XorLHS: LHS, XorRHS: RHS, Loc);
13352
13353	if (!compType.isNull() && compType->isIntegralOrUnscopedEnumerationType())
13354	return compType;
13355	return InvalidOperands(Loc, LHS, RHS);
13356	}
13357
13358	// C99 6.5.[13,14]
13359	inline QualType Sema::CheckLogicalOperands(ExprResult &LHS, ExprResult &RHS,
13360	SourceLocation Loc,
13361	BinaryOperatorKind Opc) {
13362	// Check vector operands differently.
13363	if (LHS.get()->getType()->isVectorType() ||
13364	RHS.get()->getType()->isVectorType())
13365	return CheckVectorLogicalOperands(LHS, RHS, Loc, Opc);
13366
13367	bool EnumConstantInBoolContext = false;
13368	for (const ExprResult &HS : {LHS, RHS}) {
13369	if (const auto *DREHS = dyn_cast<DeclRefExpr>(Val: HS.get())) {
13370	const auto *ECDHS = dyn_cast<EnumConstantDecl>(Val: DREHS->getDecl());
13371	if (ECDHS && ECDHS->getInitVal() != 0 && ECDHS->getInitVal() != 1)
13372	EnumConstantInBoolContext = true;
13373	}
13374	}
13375
13376	if (EnumConstantInBoolContext)
13377	Diag(Loc, DiagID: diag::warn_enum_constant_in_bool_context);
13378
13379	// WebAssembly tables can't be used with logical operators.
13380	QualType LHSTy = LHS.get()->getType();
13381	QualType RHSTy = RHS.get()->getType();
13382	const auto *LHSATy = dyn_cast<ArrayType>(Val&: LHSTy);
13383	const auto *RHSATy = dyn_cast<ArrayType>(Val&: RHSTy);
13384	if ((LHSATy && LHSATy->getElementType().isWebAssemblyReferenceType()) ||
13385	(RHSATy && RHSATy->getElementType().isWebAssemblyReferenceType())) {
13386	return InvalidOperands(Loc, LHS, RHS);
13387	}
13388
13389	// Diagnose cases where the user write a logical and/or but probably meant a
13390	// bitwise one. We do this when the LHS is a non-bool integer and the RHS
13391	// is a constant.
13392	if (!EnumConstantInBoolContext && LHS.get()->getType()->isIntegerType() &&
13393	!LHS.get()->getType()->isBooleanType() &&
13394	RHS.get()->getType()->isIntegerType() && !RHS.get()->isValueDependent() &&
13395	// Don't warn in macros or template instantiations.
13396	!Loc.isMacroID() && !inTemplateInstantiation()) {
13397	// If the RHS can be constant folded, and if it constant folds to something
13398	// that isn't 0 or 1 (which indicate a potential logical operation that
13399	// happened to fold to true/false) then warn.
13400	// Parens on the RHS are ignored.
13401	Expr::EvalResult EVResult;
13402	if (RHS.get()->EvaluateAsInt(Result&: EVResult, Ctx: Context)) {
13403	llvm::APSInt Result = EVResult.Val.getInt();
13404	if ((getLangOpts().CPlusPlus && !RHS.get()->getType()->isBooleanType() &&
13405	!RHS.get()->getExprLoc().isMacroID()) ||
13406	(Result != 0 && Result != 1)) {
13407	Diag(Loc, DiagID: diag::warn_logical_instead_of_bitwise)
13408	<< RHS.get()->getSourceRange() << (Opc == BO_LAnd ? "&&" : "||");
13409	// Suggest replacing the logical operator with the bitwise version
13410	Diag(Loc, DiagID: diag::note_logical_instead_of_bitwise_change_operator)
13411	<< (Opc == BO_LAnd ? "&" : "|")
13412	<< FixItHint::CreateReplacement(
13413	RemoveRange: SourceRange(Loc, getLocForEndOfToken(Loc)),
13414	Code: Opc == BO_LAnd ? "&" : "|");
13415	if (Opc == BO_LAnd)
13416	// Suggest replacing "Foo() && kNonZero" with "Foo()"
13417	Diag(Loc, DiagID: diag::note_logical_instead_of_bitwise_remove_constant)
13418	<< FixItHint::CreateRemoval(
13419	RemoveRange: SourceRange(getLocForEndOfToken(Loc: LHS.get()->getEndLoc()),
13420	RHS.get()->getEndLoc()));
13421	}
13422	}
13423	}
13424
13425	if (!Context.getLangOpts().CPlusPlus) {
13426	// OpenCL v1.1 s6.3.g: The logical operators and (&&), or (||) do
13427	// not operate on the built-in scalar and vector float types.
13428	if (Context.getLangOpts().OpenCL &&
13429	Context.getLangOpts().OpenCLVersion < 120) {
13430	if (LHS.get()->getType()->isFloatingType() ||
13431	RHS.get()->getType()->isFloatingType())
13432	return InvalidOperands(Loc, LHS, RHS);
13433	}
13434
13435	LHS = UsualUnaryConversions(E: LHS.get());
13436	if (LHS.isInvalid())
13437	return QualType();
13438
13439	RHS = UsualUnaryConversions(E: RHS.get());
13440	if (RHS.isInvalid())
13441	return QualType();
13442
13443	if (!LHS.get()->getType()->isScalarType() ||
13444	!RHS.get()->getType()->isScalarType())
13445	return InvalidOperands(Loc, LHS, RHS);
13446
13447	return Context.IntTy;
13448	}
13449
13450	// The following is safe because we only use this method for
13451	// non-overloadable operands.
13452
13453	// C++ [expr.log.and]p1
13454	// C++ [expr.log.or]p1
13455	// The operands are both contextually converted to type bool.
13456	ExprResult LHSRes = PerformContextuallyConvertToBool(From: LHS.get());
13457	if (LHSRes.isInvalid())
13458	return InvalidOperands(Loc, LHS, RHS);
13459	LHS = LHSRes;
13460
13461	ExprResult RHSRes = PerformContextuallyConvertToBool(From: RHS.get());
13462	if (RHSRes.isInvalid())
13463	return InvalidOperands(Loc, LHS, RHS);
13464	RHS = RHSRes;
13465
13466	// C++ [expr.log.and]p2
13467	// C++ [expr.log.or]p2
13468	// The result is a bool.
13469	return Context.BoolTy;
13470	}
13471
13472	static bool IsReadonlyMessage(Expr *E, Sema &S) {
13473	const MemberExpr *ME = dyn_cast<MemberExpr>(Val: E);
13474	if (!ME) return false;
13475	if (!isa<FieldDecl>(Val: ME->getMemberDecl())) return false;
13476	ObjCMessageExpr *Base = dyn_cast<ObjCMessageExpr>(
13477	Val: ME->getBase()->IgnoreImplicit()->IgnoreParenImpCasts());
13478	if (!Base) return false;
13479	return Base->getMethodDecl() != nullptr;
13480	}
13481
13482	/// Is the given expression (which must be 'const') a reference to a
13483	/// variable which was originally non-const, but which has become
13484	/// 'const' due to being captured within a block?
13485	enum NonConstCaptureKind { NCCK_None, NCCK_Block, NCCK_Lambda };
13486	static NonConstCaptureKind isReferenceToNonConstCapture(Sema &S, Expr *E) {
13487	assert(E->isLValue() && E->getType().isConstQualified());
13488	E = E->IgnoreParens();
13489
13490	// Must be a reference to a declaration from an enclosing scope.
13491	DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: E);
13492	if (!DRE) return NCCK_None;
13493	if (!DRE->refersToEnclosingVariableOrCapture()) return NCCK_None;
13494
13495	ValueDecl *Value = dyn_cast<ValueDecl>(Val: DRE->getDecl());
13496
13497	// The declaration must be a value which is not declared 'const'.
13498	if (!Value || Value->getType().isConstQualified())
13499	return NCCK_None;
13500
13501	BindingDecl *Binding = dyn_cast<BindingDecl>(Val: Value);
13502	if (Binding) {
13503	assert(S.getLangOpts().CPlusPlus && "BindingDecl outside of C++?");
13504	assert(!isa<BlockDecl>(Binding->getDeclContext()));
13505	return NCCK_Lambda;
13506	}
13507
13508	VarDecl *Var = dyn_cast<VarDecl>(Val: Value);
13509	if (!Var)
13510	return NCCK_None;
13511
13512	assert(Var->hasLocalStorage() && "capture added 'const' to non-local?");
13513
13514	// Decide whether the first capture was for a block or a lambda.
13515	DeclContext *DC = S.CurContext, *Prev = nullptr;
13516	// Decide whether the first capture was for a block or a lambda.
13517	while (DC) {
13518	// For init-capture, it is possible that the variable belongs to the
13519	// template pattern of the current context.
13520	if (auto *FD = dyn_cast<FunctionDecl>(Val: DC))
13521	if (Var->isInitCapture() &&
13522	FD->getTemplateInstantiationPattern() == Var->getDeclContext())
13523	break;
13524	if (DC == Var->getDeclContext())
13525	break;
13526	Prev = DC;
13527	DC = DC->getParent();
13528	}
13529	// Unless we have an init-capture, we've gone one step too far.
13530	if (!Var->isInitCapture())
13531	DC = Prev;
13532	return (isa<BlockDecl>(Val: DC) ? NCCK_Block : NCCK_Lambda);
13533	}
13534
13535	static bool IsTypeModifiable(QualType Ty, bool IsDereference) {
13536	Ty = Ty.getNonReferenceType();
13537	if (IsDereference && Ty->isPointerType())
13538	Ty = Ty->getPointeeType();
13539	return !Ty.isConstQualified();
13540	}
13541
13542	// Update err_typecheck_assign_const and note_typecheck_assign_const
13543	// when this enum is changed.
13544	enum {
13545	ConstFunction,
13546	ConstVariable,
13547	ConstMember,
13548	ConstMethod,
13549	NestedConstMember,
13550	ConstUnknown, // Keep as last element
13551	};
13552
13553	/// Emit the "read-only variable not assignable" error and print notes to give
13554	/// more information about why the variable is not assignable, such as pointing
13555	/// to the declaration of a const variable, showing that a method is const, or
13556	/// that the function is returning a const reference.
13557	static void DiagnoseConstAssignment(Sema &S, const Expr *E,
13558	SourceLocation Loc) {
13559	SourceRange ExprRange = E->getSourceRange();
13560
13561	// Only emit one error on the first const found. All other consts will emit
13562	// a note to the error.
13563	bool DiagnosticEmitted = false;
13564
13565	// Track if the current expression is the result of a dereference, and if the
13566	// next checked expression is the result of a dereference.
13567	bool IsDereference = false;
13568	bool NextIsDereference = false;
13569
13570	// Loop to process MemberExpr chains.
13571	while (true) {
13572	IsDereference = NextIsDereference;
13573
13574	E = E->IgnoreImplicit()->IgnoreParenImpCasts();
13575	if (const MemberExpr *ME = dyn_cast<MemberExpr>(Val: E)) {
13576	NextIsDereference = ME->isArrow();
13577	const ValueDecl *VD = ME->getMemberDecl();
13578	if (const FieldDecl *Field = dyn_cast<FieldDecl>(Val: VD)) {
13579	// Mutable fields can be modified even if the class is const.
13580	if (Field->isMutable()) {
13581	assert(DiagnosticEmitted && "Expected diagnostic not emitted.");
13582	break;
13583	}
13584
13585	if (!IsTypeModifiable(Ty: Field->getType(), IsDereference)) {
13586	if (!DiagnosticEmitted) {
13587	S.Diag(Loc, DiagID: diag::err_typecheck_assign_const)
13588	<< ExprRange << ConstMember << false /*static*/ << Field
13589	<< Field->getType();
13590	DiagnosticEmitted = true;
13591	}
13592	S.Diag(Loc: VD->getLocation(), DiagID: diag::note_typecheck_assign_const)
13593	<< ConstMember << false /*static*/ << Field << Field->getType()
13594	<< Field->getSourceRange();
13595	}
13596	E = ME->getBase();
13597	continue;
13598	} else if (const VarDecl *VDecl = dyn_cast<VarDecl>(Val: VD)) {
13599	if (VDecl->getType().isConstQualified()) {
13600	if (!DiagnosticEmitted) {
13601	S.Diag(Loc, DiagID: diag::err_typecheck_assign_const)
13602	<< ExprRange << ConstMember << true /*static*/ << VDecl
13603	<< VDecl->getType();
13604	DiagnosticEmitted = true;
13605	}
13606	S.Diag(Loc: VD->getLocation(), DiagID: diag::note_typecheck_assign_const)
13607	<< ConstMember << true /*static*/ << VDecl << VDecl->getType()
13608	<< VDecl->getSourceRange();
13609	}
13610	// Static fields do not inherit constness from parents.
13611	break;
13612	}
13613	break; // End MemberExpr
13614	} else if (const ArraySubscriptExpr *ASE =
13615	dyn_cast<ArraySubscriptExpr>(Val: E)) {
13616	E = ASE->getBase()->IgnoreParenImpCasts();
13617	continue;
13618	} else if (const ExtVectorElementExpr *EVE =
13619	dyn_cast<ExtVectorElementExpr>(Val: E)) {
13620	E = EVE->getBase()->IgnoreParenImpCasts();
13621	continue;
13622	}
13623	break;
13624	}
13625
13626	if (const CallExpr *CE = dyn_cast<CallExpr>(Val: E)) {
13627	// Function calls
13628	const FunctionDecl *FD = CE->getDirectCallee();
13629	if (FD && !IsTypeModifiable(Ty: FD->getReturnType(), IsDereference)) {
13630	if (!DiagnosticEmitted) {
13631	S.Diag(Loc, DiagID: diag::err_typecheck_assign_const) << ExprRange
13632	<< ConstFunction << FD;
13633	DiagnosticEmitted = true;
13634	}
13635	S.Diag(Loc: FD->getReturnTypeSourceRange().getBegin(),
13636	DiagID: diag::note_typecheck_assign_const)
13637	<< ConstFunction << FD << FD->getReturnType()
13638	<< FD->getReturnTypeSourceRange();
13639	}
13640	} else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: E)) {
13641	// Point to variable declaration.
13642	if (const ValueDecl *VD = DRE->getDecl()) {
13643	if (!IsTypeModifiable(Ty: VD->getType(), IsDereference)) {
13644	if (!DiagnosticEmitted) {
13645	S.Diag(Loc, DiagID: diag::err_typecheck_assign_const)
13646	<< ExprRange << ConstVariable << VD << VD->getType();
13647	DiagnosticEmitted = true;
13648	}
13649	S.Diag(Loc: VD->getLocation(), DiagID: diag::note_typecheck_assign_const)
13650	<< ConstVariable << VD << VD->getType() << VD->getSourceRange();
13651	}
13652	}
13653	} else if (isa<CXXThisExpr>(Val: E)) {
13654	if (const DeclContext *DC = S.getFunctionLevelDeclContext()) {
13655	if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Val: DC)) {
13656	if (MD->isConst()) {
13657	if (!DiagnosticEmitted) {
13658	S.Diag(Loc, DiagID: diag::err_typecheck_assign_const) << ExprRange
13659	<< ConstMethod << MD;
13660	DiagnosticEmitted = true;
13661	}
13662	S.Diag(Loc: MD->getLocation(), DiagID: diag::note_typecheck_assign_const)
13663	<< ConstMethod << MD << MD->getSourceRange();
13664	}
13665	}
13666	}
13667	}
13668
13669	if (DiagnosticEmitted)
13670	return;
13671
13672	// Can't determine a more specific message, so display the generic error.
13673	S.Diag(Loc, DiagID: diag::err_typecheck_assign_const) << ExprRange << ConstUnknown;
13674	}
13675
13676	enum OriginalExprKind {
13677	OEK_Variable,
13678	OEK_Member,
13679	OEK_LValue
13680	};
13681
13682	static void DiagnoseRecursiveConstFields(Sema &S, const ValueDecl *VD,
13683	const RecordType *Ty,
13684	SourceLocation Loc, SourceRange Range,
13685	OriginalExprKind OEK,
13686	bool &DiagnosticEmitted) {
13687	std::vector<const RecordType *> RecordTypeList;
13688	RecordTypeList.push_back(x: Ty);
13689	unsigned NextToCheckIndex = 0;
13690	// We walk the record hierarchy breadth-first to ensure that we print
13691	// diagnostics in field nesting order.
13692	while (RecordTypeList.size() > NextToCheckIndex) {
13693	bool IsNested = NextToCheckIndex > 0;
13694	for (const FieldDecl *Field :
13695	RecordTypeList[NextToCheckIndex]->getDecl()->fields()) {
13696	// First, check every field for constness.
13697	QualType FieldTy = Field->getType();
13698	if (FieldTy.isConstQualified()) {
13699	if (!DiagnosticEmitted) {
13700	S.Diag(Loc, DiagID: diag::err_typecheck_assign_const)
13701	<< Range << NestedConstMember << OEK << VD
13702	<< IsNested << Field;
13703	DiagnosticEmitted = true;
13704	}
13705	S.Diag(Loc: Field->getLocation(), DiagID: diag::note_typecheck_assign_const)
13706	<< NestedConstMember << IsNested << Field
13707	<< FieldTy << Field->getSourceRange();
13708	}
13709
13710	// Then we append it to the list to check next in order.
13711	FieldTy = FieldTy.getCanonicalType();
13712	if (const auto *FieldRecTy = FieldTy->getAs<RecordType>()) {
13713	if (!llvm::is_contained(Range&: RecordTypeList, Element: FieldRecTy))
13714	RecordTypeList.push_back(x: FieldRecTy);
13715	}
13716	}
13717	++NextToCheckIndex;
13718	}
13719	}
13720
13721	/// Emit an error for the case where a record we are trying to assign to has a
13722	/// const-qualified field somewhere in its hierarchy.
13723	static void DiagnoseRecursiveConstFields(Sema &S, const Expr *E,
13724	SourceLocation Loc) {
13725	QualType Ty = E->getType();
13726	assert(Ty->isRecordType() && "lvalue was not record?");
13727	SourceRange Range = E->getSourceRange();
13728	const RecordType *RTy = Ty.getCanonicalType()->getAs<RecordType>();
13729	bool DiagEmitted = false;
13730
13731	if (const MemberExpr *ME = dyn_cast<MemberExpr>(Val: E))
13732	DiagnoseRecursiveConstFields(S, VD: ME->getMemberDecl(), Ty: RTy, Loc,
13733	Range, OEK: OEK_Member, DiagnosticEmitted&: DiagEmitted);
13734	else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: E))
13735	DiagnoseRecursiveConstFields(S, VD: DRE->getDecl(), Ty: RTy, Loc,
13736	Range, OEK: OEK_Variable, DiagnosticEmitted&: DiagEmitted);
13737	else
13738	DiagnoseRecursiveConstFields(S, VD: nullptr, Ty: RTy, Loc,
13739	Range, OEK: OEK_LValue, DiagnosticEmitted&: DiagEmitted);
13740	if (!DiagEmitted)
13741	DiagnoseConstAssignment(S, E, Loc);
13742	}
13743
13744	/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not,
13745	/// emit an error and return true. If so, return false.
13746	static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) {
13747	assert(!E->hasPlaceholderType(BuiltinType::PseudoObject));
13748
13749	S.CheckShadowingDeclModification(E, Loc);
13750
13751	SourceLocation OrigLoc = Loc;
13752	Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(Ctx&: S.Context,
13753	Loc: &Loc);
13754	if (IsLV == Expr::MLV_ClassTemporary && IsReadonlyMessage(E, S))
13755	IsLV = Expr::MLV_InvalidMessageExpression;
13756	if (IsLV == Expr::MLV_Valid)
13757	return false;
13758
13759	unsigned DiagID = 0;
13760	bool NeedType = false;
13761	switch (IsLV) { // C99 6.5.16p2
13762	case Expr::MLV_ConstQualified:
13763	// Use a specialized diagnostic when we're assigning to an object
13764	// from an enclosing function or block.
13765	if (NonConstCaptureKind NCCK = isReferenceToNonConstCapture(S, E)) {
13766	if (NCCK == NCCK_Block)
13767	DiagID = diag::err_block_decl_ref_not_modifiable_lvalue;
13768	else
13769	DiagID = diag::err_lambda_decl_ref_not_modifiable_lvalue;
13770	break;
13771	}
13772
13773	// In ARC, use some specialized diagnostics for occasions where we
13774	// infer 'const'. These are always pseudo-strong variables.
13775	if (S.getLangOpts().ObjCAutoRefCount) {
13776	DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(Val: E->IgnoreParenCasts());
13777	if (declRef && isa<VarDecl>(Val: declRef->getDecl())) {
13778	VarDecl *var = cast<VarDecl>(Val: declRef->getDecl());
13779
13780	// Use the normal diagnostic if it's pseudo-__strong but the
13781	// user actually wrote 'const'.
13782	if (var->isARCPseudoStrong() &&
13783	(!var->getTypeSourceInfo() ||
13784	!var->getTypeSourceInfo()->getType().isConstQualified())) {
13785	// There are three pseudo-strong cases:
13786	// - self
13787	ObjCMethodDecl *method = S.getCurMethodDecl();
13788	if (method && var == method->getSelfDecl()) {
13789	DiagID = method->isClassMethod()
13790	? diag::err_typecheck_arc_assign_self_class_method
13791	: diag::err_typecheck_arc_assign_self;
13792
13793	// - Objective-C externally_retained attribute.
13794	} else if (var->hasAttr<ObjCExternallyRetainedAttr>() ||
13795	isa<ParmVarDecl>(Val: var)) {
13796	DiagID = diag::err_typecheck_arc_assign_externally_retained;
13797
13798	// - fast enumeration variables
13799	} else {
13800	DiagID = diag::err_typecheck_arr_assign_enumeration;
13801	}
13802
13803	SourceRange Assign;
13804	if (Loc != OrigLoc)
13805	Assign = SourceRange(OrigLoc, OrigLoc);
13806	S.Diag(Loc, DiagID) << E->getSourceRange() << Assign;
13807	// We need to preserve the AST regardless, so migration tool
13808	// can do its job.
13809	return false;
13810	}
13811	}
13812	}
13813
13814	// If none of the special cases above are triggered, then this is a
13815	// simple const assignment.
13816	if (DiagID == 0) {
13817	DiagnoseConstAssignment(S, E, Loc);
13818	return true;
13819	}
13820
13821	break;
13822	case Expr::MLV_ConstAddrSpace:
13823	DiagnoseConstAssignment(S, E, Loc);
13824	return true;
13825	case Expr::MLV_ConstQualifiedField:
13826	DiagnoseRecursiveConstFields(S, E, Loc);
13827	return true;
13828	case Expr::MLV_ArrayType:
13829	case Expr::MLV_ArrayTemporary:
13830	DiagID = diag::err_typecheck_array_not_modifiable_lvalue;
13831	NeedType = true;
13832	break;
13833	case Expr::MLV_NotObjectType:
13834	DiagID = diag::err_typecheck_non_object_not_modifiable_lvalue;
13835	NeedType = true;
13836	break;
13837	case Expr::MLV_LValueCast:
13838	DiagID = diag::err_typecheck_lvalue_casts_not_supported;
13839	break;
13840	case Expr::MLV_Valid:
13841	llvm_unreachable("did not take early return for MLV_Valid");
13842	case Expr::MLV_InvalidExpression:
13843	case Expr::MLV_MemberFunction:
13844	case Expr::MLV_ClassTemporary:
13845	DiagID = diag::err_typecheck_expression_not_modifiable_lvalue;
13846	break;
13847	case Expr::MLV_IncompleteType:
13848	case Expr::MLV_IncompleteVoidType:
13849	return S.RequireCompleteType(Loc, T: E->getType(),
13850	DiagID: diag::err_typecheck_incomplete_type_not_modifiable_lvalue, Args: E);
13851	case Expr::MLV_DuplicateVectorComponents:
13852	DiagID = diag::err_typecheck_duplicate_vector_components_not_mlvalue;
13853	break;
13854	case Expr::MLV_NoSetterProperty:
13855	llvm_unreachable("readonly properties should be processed differently");
13856	case Expr::MLV_InvalidMessageExpression:
13857	DiagID = diag::err_readonly_message_assignment;
13858	break;
13859	case Expr::MLV_SubObjCPropertySetting:
13860	DiagID = diag::err_no_subobject_property_setting;
13861	break;
13862	}
13863
13864	SourceRange Assign;
13865	if (Loc != OrigLoc)
13866	Assign = SourceRange(OrigLoc, OrigLoc);
13867	if (NeedType)
13868	S.Diag(Loc, DiagID) << E->getType() << E->getSourceRange() << Assign;
13869	else
13870	S.Diag(Loc, DiagID) << E->getSourceRange() << Assign;
13871	return true;
13872	}
13873
13874	static void CheckIdentityFieldAssignment(Expr *LHSExpr, Expr *RHSExpr,
13875	SourceLocation Loc,
13876	Sema &Sema) {
13877	if (Sema.inTemplateInstantiation())
13878	return;
13879	if (Sema.isUnevaluatedContext())
13880	return;
13881	if (Loc.isInvalid() || Loc.isMacroID())
13882	return;
13883	if (LHSExpr->getExprLoc().isMacroID() || RHSExpr->getExprLoc().isMacroID())
13884	return;
13885
13886	// C / C++ fields
13887	MemberExpr *ML = dyn_cast<MemberExpr>(Val: LHSExpr);
13888	MemberExpr *MR = dyn_cast<MemberExpr>(Val: RHSExpr);
13889	if (ML && MR) {
13890	if (!(isa<CXXThisExpr>(Val: ML->getBase()) && isa<CXXThisExpr>(Val: MR->getBase())))
13891	return;
13892	const ValueDecl *LHSDecl =
13893	cast<ValueDecl>(Val: ML->getMemberDecl()->getCanonicalDecl());
13894	const ValueDecl *RHSDecl =
13895	cast<ValueDecl>(Val: MR->getMemberDecl()->getCanonicalDecl());
13896	if (LHSDecl != RHSDecl)
13897	return;
13898	if (LHSDecl->getType().isVolatileQualified())
13899	return;
13900	if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>())
13901	if (RefTy->getPointeeType().isVolatileQualified())
13902	return;
13903
13904	Sema.Diag(Loc, DiagID: diag::warn_identity_field_assign) << 0;
13905	}
13906
13907	// Objective-C instance variables
13908	ObjCIvarRefExpr *OL = dyn_cast<ObjCIvarRefExpr>(Val: LHSExpr);
13909	ObjCIvarRefExpr *OR = dyn_cast<ObjCIvarRefExpr>(Val: RHSExpr);
13910	if (OL && OR && OL->getDecl() == OR->getDecl()) {
13911	DeclRefExpr *RL = dyn_cast<DeclRefExpr>(Val: OL->getBase()->IgnoreImpCasts());
13912	DeclRefExpr *RR = dyn_cast<DeclRefExpr>(Val: OR->getBase()->IgnoreImpCasts());
13913	if (RL && RR && RL->getDecl() == RR->getDecl())
13914	Sema.Diag(Loc, DiagID: diag::warn_identity_field_assign) << 1;
13915	}
13916	}
13917
13918	// C99 6.5.16.1
13919	QualType Sema::CheckAssignmentOperands(Expr *LHSExpr, ExprResult &RHS,
13920	SourceLocation Loc,
13921	QualType CompoundType,
13922	BinaryOperatorKind Opc) {
13923	assert(!LHSExpr->hasPlaceholderType(BuiltinType::PseudoObject));
13924
13925	// Verify that LHS is a modifiable lvalue, and emit error if not.
13926	if (CheckForModifiableLvalue(E: LHSExpr, Loc, S&: *this))
13927	return QualType();
13928
13929	QualType LHSType = LHSExpr->getType();
13930	QualType RHSType = CompoundType.isNull() ? RHS.get()->getType() :
13931	CompoundType;
13932
13933	if (RHS.isUsable()) {
13934	// Even if this check fails don't return early to allow the best
13935	// possible error recovery and to allow any subsequent diagnostics to
13936	// work.
13937	const ValueDecl *Assignee = nullptr;
13938	bool ShowFullyQualifiedAssigneeName = false;
13939	// In simple cases describe what is being assigned to
13940	if (auto *DR = dyn_cast<DeclRefExpr>(Val: LHSExpr->IgnoreParenCasts())) {
13941	Assignee = DR->getDecl();
13942	} else if (auto *ME = dyn_cast<MemberExpr>(Val: LHSExpr->IgnoreParenCasts())) {
13943	Assignee = ME->getMemberDecl();
13944	ShowFullyQualifiedAssigneeName = true;
13945	}
13946
13947	BoundsSafetyCheckAssignmentToCountAttrPtr(
13948	LHSTy: LHSType, RHSExpr: RHS.get(), Action: AssignmentAction::Assigning, Loc, Assignee,
13949	ShowFullyQualifiedAssigneeName);
13950	}
13951
13952	// OpenCL v1.2 s6.1.1.1 p2:
13953	// The half data type can only be used to declare a pointer to a buffer that
13954	// contains half values
13955	if (getLangOpts().OpenCL &&
13956	!getOpenCLOptions().isAvailableOption(Ext: "cl_khr_fp16", LO: getLangOpts()) &&
13957	LHSType->isHalfType()) {
13958	Diag(Loc, DiagID: diag::err_opencl_half_load_store) << 1
13959	<< LHSType.getUnqualifiedType();
13960	return QualType();
13961	}
13962
13963	// WebAssembly tables can't be used on RHS of an assignment expression.
13964	if (RHSType->isWebAssemblyTableType()) {
13965	Diag(Loc, DiagID: diag::err_wasm_table_art) << 0;
13966	return QualType();
13967	}
13968
13969	AssignConvertType ConvTy;
13970	if (CompoundType.isNull()) {
13971	Expr *RHSCheck = RHS.get();
13972
13973	CheckIdentityFieldAssignment(LHSExpr, RHSExpr: RHSCheck, Loc, Sema&: *this);
13974
13975	QualType LHSTy(LHSType);
13976	ConvTy = CheckSingleAssignmentConstraints(LHSType: LHSTy, CallerRHS&: RHS);
13977	if (RHS.isInvalid())
13978	return QualType();
13979	// Special case of NSObject attributes on c-style pointer types.
13980	if (ConvTy == AssignConvertType::IncompatiblePointer &&
13981	((Context.isObjCNSObjectType(Ty: LHSType) &&
13982	RHSType->isObjCObjectPointerType()) ||
13983	(Context.isObjCNSObjectType(Ty: RHSType) &&
13984	LHSType->isObjCObjectPointerType())))
13985	ConvTy = AssignConvertType::Compatible;
13986
13987	if (IsAssignConvertCompatible(ConvTy) && LHSType->isObjCObjectType())
13988	Diag(Loc, DiagID: diag::err_objc_object_assignment) << LHSType;
13989
13990	// If the RHS is a unary plus or minus, check to see if they = and + are
13991	// right next to each other. If so, the user may have typo'd "x =+ 4"
13992	// instead of "x += 4".
13993	if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Val: RHSCheck))
13994	RHSCheck = ICE->getSubExpr();
13995	if (UnaryOperator *UO = dyn_cast<UnaryOperator>(Val: RHSCheck)) {
13996	if ((UO->getOpcode() == UO_Plus || UO->getOpcode() == UO_Minus) &&
13997	Loc.isFileID() && UO->getOperatorLoc().isFileID() &&
13998	// Only if the two operators are exactly adjacent.
13999	Loc.getLocWithOffset(Offset: 1) == UO->getOperatorLoc() &&
14000	// And there is a space or other character before the subexpr of the
14001	// unary +/-. We don't want to warn on "x=-1".
14002	Loc.getLocWithOffset(Offset: 2) != UO->getSubExpr()->getBeginLoc() &&
14003	UO->getSubExpr()->getBeginLoc().isFileID()) {
14004	Diag(Loc, DiagID: diag::warn_not_compound_assign)
14005	<< (UO->getOpcode() == UO_Plus ? "+" : "-")
14006	<< SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc());
14007	}
14008	}
14009
14010	if (IsAssignConvertCompatible(ConvTy)) {
14011	if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong) {
14012	// Warn about retain cycles where a block captures the LHS, but
14013	// not if the LHS is a simple variable into which the block is
14014	// being stored...unless that variable can be captured by reference!
14015	const Expr *InnerLHS = LHSExpr->IgnoreParenCasts();
14016	const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: InnerLHS);
14017	if (!DRE || DRE->getDecl()->hasAttr<BlocksAttr>())
14018	ObjC().checkRetainCycles(receiver: LHSExpr, argument: RHS.get());
14019	}
14020
14021	if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong ||
14022	LHSType.isNonWeakInMRRWithObjCWeak(Context)) {
14023	// It is safe to assign a weak reference into a strong variable.
14024	// Although this code can still have problems:
14025	// id x = self.weakProp;
14026	// id y = self.weakProp;
14027	// we do not warn to warn spuriously when 'x' and 'y' are on separate
14028	// paths through the function. This should be revisited if
14029	// -Wrepeated-use-of-weak is made flow-sensitive.
14030	// For ObjCWeak only, we do not warn if the assign is to a non-weak
14031	// variable, which will be valid for the current autorelease scope.
14032	if (!Diags.isIgnored(DiagID: diag::warn_arc_repeated_use_of_weak,
14033	Loc: RHS.get()->getBeginLoc()))
14034	getCurFunction()->markSafeWeakUse(E: RHS.get());
14035
14036	} else if (getLangOpts().ObjCAutoRefCount || getLangOpts().ObjCWeak) {
14037	checkUnsafeExprAssigns(Loc, LHS: LHSExpr, RHS: RHS.get());
14038	}
14039	}
14040	} else {
14041	// Compound assignment "x += y"
14042	ConvTy = CheckAssignmentConstraints(Loc, LHSType, RHSType);
14043	}
14044
14045	if (DiagnoseAssignmentResult(ConvTy, Loc, DstType: LHSType, SrcType: RHSType, SrcExpr: RHS.get(),
14046	Action: AssignmentAction::Assigning))
14047	return QualType();
14048
14049	CheckForNullPointerDereference(S&: *this, E: LHSExpr);
14050
14051	AssignedEntity AE{.LHS: LHSExpr};
14052	checkAssignmentLifetime(SemaRef&: *this, Entity: AE, Init: RHS.get());
14053
14054	if (getLangOpts().CPlusPlus20 && LHSType.isVolatileQualified()) {
14055	if (CompoundType.isNull()) {
14056	// C++2a [expr.ass]p5:
14057	// A simple-assignment whose left operand is of a volatile-qualified
14058	// type is deprecated unless the assignment is either a discarded-value
14059	// expression or an unevaluated operand
14060	ExprEvalContexts.back().VolatileAssignmentLHSs.push_back(Elt: LHSExpr);
14061	}
14062	}
14063
14064	// C11 6.5.16p3: The type of an assignment expression is the type of the
14065	// left operand would have after lvalue conversion.
14066	// C11 6.3.2.1p2: ...this is called lvalue conversion. If the lvalue has
14067	// qualified type, the value has the unqualified version of the type of the
14068	// lvalue; additionally, if the lvalue has atomic type, the value has the
14069	// non-atomic version of the type of the lvalue.
14070	// C++ 5.17p1: the type of the assignment expression is that of its left
14071	// operand.
14072	return getLangOpts().CPlusPlus ? LHSType : LHSType.getAtomicUnqualifiedType();
14073	}
14074
14075	// Scenarios to ignore if expression E is:
14076	// 1. an explicit cast expression into void
14077	// 2. a function call expression that returns void
14078	static bool IgnoreCommaOperand(const Expr *E, const ASTContext &Context) {
14079	E = E->IgnoreParens();
14080
14081	if (const CastExpr *CE = dyn_cast<CastExpr>(Val: E)) {
14082	if (CE->getCastKind() == CK_ToVoid) {
14083	return true;
14084	}
14085
14086	// static_cast<void> on a dependent type will not show up as CK_ToVoid.
14087	if (CE->getCastKind() == CK_Dependent && E->getType()->isVoidType() &&
14088	CE->getSubExpr()->getType()->isDependentType()) {
14089	return true;
14090	}
14091	}
14092
14093	if (const auto *CE = dyn_cast<CallExpr>(Val: E))
14094	return CE->getCallReturnType(Ctx: Context)->isVoidType();
14095	return false;
14096	}
14097
14098	void Sema::DiagnoseCommaOperator(const Expr *LHS, SourceLocation Loc) {
14099	// No warnings in macros
14100	if (Loc.isMacroID())
14101	return;
14102
14103	// Don't warn in template instantiations.
14104	if (inTemplateInstantiation())
14105	return;
14106
14107	// Scope isn't fine-grained enough to explicitly list the specific cases, so
14108	// instead, skip more than needed, then call back into here with the
14109	// CommaVisitor in SemaStmt.cpp.
14110	// The listed locations are the initialization and increment portions
14111	// of a for loop. The additional checks are on the condition of
14112	// if statements, do/while loops, and for loops.
14113	// Differences in scope flags for C89 mode requires the extra logic.
14114	const unsigned ForIncrementFlags =
14115	getLangOpts().C99 || getLangOpts().CPlusPlus
14116	? Scope::ControlScope | Scope::ContinueScope | Scope::BreakScope
14117	: Scope::ContinueScope | Scope::BreakScope;
14118	const unsigned ForInitFlags = Scope::ControlScope | Scope::DeclScope;
14119	const unsigned ScopeFlags = getCurScope()->getFlags();
14120	if ((ScopeFlags & ForIncrementFlags) == ForIncrementFlags ||
14121	(ScopeFlags & ForInitFlags) == ForInitFlags)
14122	return;
14123
14124	// If there are multiple comma operators used together, get the RHS of the
14125	// of the comma operator as the LHS.
14126	while (const BinaryOperator *BO = dyn_cast<BinaryOperator>(Val: LHS)) {
14127	if (BO->getOpcode() != BO_Comma)
14128	break;
14129	LHS = BO->getRHS();
14130	}
14131
14132	// Only allow some expressions on LHS to not warn.
14133	if (IgnoreCommaOperand(E: LHS, Context))
14134	return;
14135
14136	Diag(Loc, DiagID: diag::warn_comma_operator);
14137	Diag(Loc: LHS->getBeginLoc(), DiagID: diag::note_cast_to_void)
14138	<< LHS->getSourceRange()
14139	<< FixItHint::CreateInsertion(InsertionLoc: LHS->getBeginLoc(),
14140	Code: LangOpts.CPlusPlus ? "static_cast<void>("
14141	: "(void)(")
14142	<< FixItHint::CreateInsertion(InsertionLoc: PP.getLocForEndOfToken(Loc: LHS->getEndLoc()),
14143	Code: ")");
14144	}
14145
14146	// C99 6.5.17
14147	static QualType CheckCommaOperands(Sema &S, ExprResult &LHS, ExprResult &RHS,
14148	SourceLocation Loc) {
14149	LHS = S.CheckPlaceholderExpr(E: LHS.get());
14150	RHS = S.CheckPlaceholderExpr(E: RHS.get());
14151	if (LHS.isInvalid() || RHS.isInvalid())
14152	return QualType();
14153
14154	// C's comma performs lvalue conversion (C99 6.3.2.1) on both its
14155	// operands, but not unary promotions.
14156	// C++'s comma does not do any conversions at all (C++ [expr.comma]p1).
14157
14158	// So we treat the LHS as a ignored value, and in C++ we allow the
14159	// containing site to determine what should be done with the RHS.
14160	LHS = S.IgnoredValueConversions(E: LHS.get());
14161	if (LHS.isInvalid())
14162	return QualType();
14163
14164	S.DiagnoseUnusedExprResult(S: LHS.get(), DiagID: diag::warn_unused_comma_left_operand);
14165
14166	if (!S.getLangOpts().CPlusPlus) {
14167	RHS = S.DefaultFunctionArrayLvalueConversion(E: RHS.get());
14168	if (RHS.isInvalid())
14169	return QualType();
14170	if (!RHS.get()->getType()->isVoidType())
14171	S.RequireCompleteType(Loc, T: RHS.get()->getType(),
14172	DiagID: diag::err_incomplete_type);
14173	}
14174
14175	if (!S.getDiagnostics().isIgnored(DiagID: diag::warn_comma_operator, Loc))
14176	S.DiagnoseCommaOperator(LHS: LHS.get(), Loc);
14177
14178	return RHS.get()->getType();
14179	}
14180
14181	/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine
14182	/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions.
14183	static QualType CheckIncrementDecrementOperand(Sema &S, Expr *Op,
14184	ExprValueKind &VK,
14185	ExprObjectKind &OK,
14186	SourceLocation OpLoc, bool IsInc,
14187	bool IsPrefix) {
14188	QualType ResType = Op->getType();
14189	// Atomic types can be used for increment / decrement where the non-atomic
14190	// versions can, so ignore the _Atomic() specifier for the purpose of
14191	// checking.
14192	if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
14193	ResType = ResAtomicType->getValueType();
14194
14195	assert(!ResType.isNull() && "no type for increment/decrement expression");
14196
14197	if (S.getLangOpts().CPlusPlus && ResType->isBooleanType()) {
14198	// Decrement of bool is not allowed.
14199	if (!IsInc) {
14200	S.Diag(Loc: OpLoc, DiagID: diag::err_decrement_bool) << Op->getSourceRange();
14201	return QualType();
14202	}
14203	// Increment of bool sets it to true, but is deprecated.
14204	S.Diag(Loc: OpLoc, DiagID: S.getLangOpts().CPlusPlus17 ? diag::ext_increment_bool
14205	: diag::warn_increment_bool)
14206	<< Op->getSourceRange();
14207	} else if (S.getLangOpts().CPlusPlus && ResType->isEnumeralType()) {
14208	// Error on enum increments and decrements in C++ mode
14209	S.Diag(Loc: OpLoc, DiagID: diag::err_increment_decrement_enum) << IsInc << ResType;
14210	return QualType();
14211	} else if (ResType->isRealType()) {
14212	// OK!
14213	} else if (ResType->isPointerType()) {
14214	// C99 6.5.2.4p2, 6.5.6p2
14215	if (!checkArithmeticOpPointerOperand(S, Loc: OpLoc, Operand: Op))
14216	return QualType();
14217	} else if (ResType->isObjCObjectPointerType()) {
14218	// On modern runtimes, ObjC pointer arithmetic is forbidden.
14219	// Otherwise, we just need a complete type.
14220	if (checkArithmeticIncompletePointerType(S, Loc: OpLoc, Operand: Op) ||
14221	checkArithmeticOnObjCPointer(S, opLoc: OpLoc, op: Op))
14222	return QualType();
14223	} else if (ResType->isAnyComplexType()) {
14224	// C99 does not support ++/-- on complex types, we allow as an extension.
14225	S.Diag(Loc: OpLoc, DiagID: S.getLangOpts().C2y ? diag::warn_c2y_compat_increment_complex
14226	: diag::ext_c2y_increment_complex)
14227	<< IsInc << Op->getSourceRange();
14228	} else if (ResType->isPlaceholderType()) {
14229	ExprResult PR = S.CheckPlaceholderExpr(E: Op);
14230	if (PR.isInvalid()) return QualType();
14231	return CheckIncrementDecrementOperand(S, Op: PR.get(), VK, OK, OpLoc,
14232	IsInc, IsPrefix);
14233	} else if (S.getLangOpts().AltiVec && ResType->isVectorType()) {
14234	// OK! ( C/C++ Language Extensions for CBEA(Version 2.6) 10.3 )
14235	} else if (S.getLangOpts().ZVector && ResType->isVectorType() &&
14236	(ResType->castAs<VectorType>()->getVectorKind() !=
14237	VectorKind::AltiVecBool)) {
14238	// The z vector extensions allow ++ and -- for non-bool vectors.
14239	} else if (S.getLangOpts().OpenCL && ResType->isVectorType() &&
14240	ResType->castAs<VectorType>()->getElementType()->isIntegerType()) {
14241	// OpenCL V1.2 6.3 says dec/inc ops operate on integer vector types.
14242	} else {
14243	S.Diag(Loc: OpLoc, DiagID: diag::err_typecheck_illegal_increment_decrement)
14244	<< ResType << int(IsInc) << Op->getSourceRange();
14245	return QualType();
14246	}
14247	// At this point, we know we have a real, complex or pointer type.
14248	// Now make sure the operand is a modifiable lvalue.
14249	if (CheckForModifiableLvalue(E: Op, Loc: OpLoc, S))
14250	return QualType();
14251	if (S.getLangOpts().CPlusPlus20 && ResType.isVolatileQualified()) {
14252	// C++2a [expr.pre.inc]p1, [expr.post.inc]p1:
14253	// An operand with volatile-qualified type is deprecated
14254	S.Diag(Loc: OpLoc, DiagID: diag::warn_deprecated_increment_decrement_volatile)
14255	<< IsInc << ResType;
14256	}
14257	// In C++, a prefix increment is the same type as the operand. Otherwise
14258	// (in C or with postfix), the increment is the unqualified type of the
14259	// operand.
14260	if (IsPrefix && S.getLangOpts().CPlusPlus) {
14261	VK = VK_LValue;
14262	OK = Op->getObjectKind();
14263	return ResType;
14264	} else {
14265	VK = VK_PRValue;
14266	return ResType.getUnqualifiedType();
14267	}
14268	}
14269
14270	/// getPrimaryDecl - Helper function for CheckAddressOfOperand().
14271	/// This routine allows us to typecheck complex/recursive expressions
14272	/// where the declaration is needed for type checking. We only need to
14273	/// handle cases when the expression references a function designator
14274	/// or is an lvalue. Here are some examples:
14275	/// - &(x) => x
14276	/// - &*****f => f for f a function designator.
14277	/// - &s.xx => s
14278	/// - &s.zz[1].yy -> s, if zz is an array
14279	/// - *(x + 1) -> x, if x is an array
14280	/// - &"123"[2] -> 0
14281	/// - & __real__ x -> x
14282	///
14283	/// FIXME: We don't recurse to the RHS of a comma, nor handle pointers to
14284	/// members.
14285	static ValueDecl *getPrimaryDecl(Expr *E) {
14286	switch (E->getStmtClass()) {
14287	case Stmt::DeclRefExprClass:
14288	return cast<DeclRefExpr>(Val: E)->getDecl();
14289	case Stmt::MemberExprClass:
14290	// If this is an arrow operator, the address is an offset from
14291	// the base's value, so the object the base refers to is
14292	// irrelevant.
14293	if (cast<MemberExpr>(Val: E)->isArrow())
14294	return nullptr;
14295	// Otherwise, the expression refers to a part of the base
14296	return getPrimaryDecl(E: cast<MemberExpr>(Val: E)->getBase());
14297	case Stmt::ArraySubscriptExprClass: {
14298	// FIXME: This code shouldn't be necessary! We should catch the implicit
14299	// promotion of register arrays earlier.
14300	Expr* Base = cast<ArraySubscriptExpr>(Val: E)->getBase();
14301	if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Val: Base)) {
14302	if (ICE->getSubExpr()->getType()->isArrayType())
14303	return getPrimaryDecl(E: ICE->getSubExpr());
14304	}
14305	return nullptr;
14306	}
14307	case Stmt::UnaryOperatorClass: {
14308	UnaryOperator *UO = cast<UnaryOperator>(Val: E);
14309
14310	switch(UO->getOpcode()) {
14311	case UO_Real:
14312	case UO_Imag:
14313	case UO_Extension:
14314	return getPrimaryDecl(E: UO->getSubExpr());
14315	default:
14316	return nullptr;
14317	}
14318	}
14319	case Stmt::ParenExprClass:
14320	return getPrimaryDecl(E: cast<ParenExpr>(Val: E)->getSubExpr());
14321	case Stmt::ImplicitCastExprClass:
14322	// If the result of an implicit cast is an l-value, we care about
14323	// the sub-expression; otherwise, the result here doesn't matter.
14324	return getPrimaryDecl(E: cast<ImplicitCastExpr>(Val: E)->getSubExpr());
14325	case Stmt::CXXUuidofExprClass:
14326	return cast<CXXUuidofExpr>(Val: E)->getGuidDecl();
14327	default:
14328	return nullptr;
14329	}
14330	}
14331
14332	namespace {
14333	enum {
14334	AO_Bit_Field = 0,
14335	AO_Vector_Element = 1,
14336	AO_Property_Expansion = 2,
14337	AO_Register_Variable = 3,
14338	AO_Matrix_Element = 4,
14339	AO_No_Error = 5
14340	};
14341	}
14342	/// Diagnose invalid operand for address of operations.
14343	///
14344	/// \param Type The type of operand which cannot have its address taken.
14345	static void diagnoseAddressOfInvalidType(Sema &S, SourceLocation Loc,
14346	Expr *E, unsigned Type) {
14347	S.Diag(Loc, DiagID: diag::err_typecheck_address_of) << Type << E->getSourceRange();
14348	}
14349
14350	bool Sema::CheckUseOfCXXMethodAsAddressOfOperand(SourceLocation OpLoc,
14351	const Expr *Op,
14352	const CXXMethodDecl *MD) {
14353	const auto *DRE = cast<DeclRefExpr>(Val: Op->IgnoreParens());
14354
14355	if (Op != DRE)
14356	return Diag(Loc: OpLoc, DiagID: diag::err_parens_pointer_member_function)
14357	<< Op->getSourceRange();
14358
14359	// Taking the address of a dtor is illegal per C++ [class.dtor]p2.
14360	if (isa<CXXDestructorDecl>(Val: MD))
14361	return Diag(Loc: OpLoc, DiagID: diag::err_typecheck_addrof_dtor)
14362	<< DRE->getSourceRange();
14363
14364	if (DRE->getQualifier())
14365	return false;
14366
14367	if (MD->getParent()->getName().empty())
14368	return Diag(Loc: OpLoc, DiagID: diag::err_unqualified_pointer_member_function)
14369	<< DRE->getSourceRange();
14370
14371	SmallString<32> Str;
14372	StringRef Qual = (MD->getParent()->getName() + "::").toStringRef(Out&: Str);
14373	return Diag(Loc: OpLoc, DiagID: diag::err_unqualified_pointer_member_function)
14374	<< DRE->getSourceRange()
14375	<< FixItHint::CreateInsertion(InsertionLoc: DRE->getSourceRange().getBegin(), Code: Qual);
14376	}
14377
14378	QualType Sema::CheckAddressOfOperand(ExprResult &OrigOp, SourceLocation OpLoc) {
14379	if (const BuiltinType *PTy = OrigOp.get()->getType()->getAsPlaceholderType()){
14380	if (PTy->getKind() == BuiltinType::Overload) {
14381	Expr *E = OrigOp.get()->IgnoreParens();
14382	if (!isa<OverloadExpr>(Val: E)) {
14383	assert(cast<UnaryOperator>(E)->getOpcode() == UO_AddrOf);
14384	Diag(Loc: OpLoc, DiagID: diag::err_typecheck_invalid_lvalue_addrof_addrof_function)
14385	<< OrigOp.get()->getSourceRange();
14386	return QualType();
14387	}
14388
14389	OverloadExpr *Ovl = cast<OverloadExpr>(Val: E);
14390	if (isa<UnresolvedMemberExpr>(Val: Ovl))
14391	if (!ResolveSingleFunctionTemplateSpecialization(ovl: Ovl)) {
14392	Diag(Loc: OpLoc, DiagID: diag::err_invalid_form_pointer_member_function)
14393	<< OrigOp.get()->getSourceRange();
14394	return QualType();
14395	}
14396
14397	return Context.OverloadTy;
14398	}
14399
14400	if (PTy->getKind() == BuiltinType::UnknownAny)
14401	return Context.UnknownAnyTy;
14402
14403	if (PTy->getKind() == BuiltinType::BoundMember) {
14404	Diag(Loc: OpLoc, DiagID: diag::err_invalid_form_pointer_member_function)
14405	<< OrigOp.get()->getSourceRange();
14406	return QualType();
14407	}
14408
14409	OrigOp = CheckPlaceholderExpr(E: OrigOp.get());
14410	if (OrigOp.isInvalid()) return QualType();
14411	}
14412
14413	if (OrigOp.get()->isTypeDependent())
14414	return Context.DependentTy;
14415
14416	assert(!OrigOp.get()->hasPlaceholderType());
14417
14418	// Make sure to ignore parentheses in subsequent checks
14419	Expr *op = OrigOp.get()->IgnoreParens();
14420
14421	// In OpenCL captures for blocks called as lambda functions
14422	// are located in the private address space. Blocks used in
14423	// enqueue_kernel can be located in a different address space
14424	// depending on a vendor implementation. Thus preventing
14425	// taking an address of the capture to avoid invalid AS casts.
14426	if (LangOpts.OpenCL) {
14427	auto* VarRef = dyn_cast<DeclRefExpr>(Val: op);
14428	if (VarRef && VarRef->refersToEnclosingVariableOrCapture()) {
14429	Diag(Loc: op->getExprLoc(), DiagID: diag::err_opencl_taking_address_capture);
14430	return QualType();
14431	}
14432	}
14433
14434	if (getLangOpts().C99) {
14435	// Implement C99-only parts of addressof rules.
14436	if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(Val: op)) {
14437	if (uOp->getOpcode() == UO_Deref)
14438	// Per C99 6.5.3.2, the address of a deref always returns a valid result
14439	// (assuming the deref expression is valid).
14440	return uOp->getSubExpr()->getType();
14441	}
14442	// Technically, there should be a check for array subscript
14443	// expressions here, but the result of one is always an lvalue anyway.
14444	}
14445	ValueDecl *dcl = getPrimaryDecl(E: op);
14446
14447	if (auto *FD = dyn_cast_or_null<FunctionDecl>(Val: dcl))
14448	if (!checkAddressOfFunctionIsAvailable(Function: FD, /*Complain=*/true,
14449	Loc: op->getBeginLoc()))
14450	return QualType();
14451
14452	Expr::LValueClassification lval = op->ClassifyLValue(Ctx&: Context);
14453	unsigned AddressOfError = AO_No_Error;
14454
14455	if (lval == Expr::LV_ClassTemporary || lval == Expr::LV_ArrayTemporary) {
14456	bool sfinae = (bool)isSFINAEContext();
14457	Diag(Loc: OpLoc, DiagID: isSFINAEContext() ? diag::err_typecheck_addrof_temporary
14458	: diag::ext_typecheck_addrof_temporary)
14459	<< op->getType() << op->getSourceRange();
14460	if (sfinae)
14461	return QualType();
14462	// Materialize the temporary as an lvalue so that we can take its address.
14463	OrigOp = op =
14464	CreateMaterializeTemporaryExpr(T: op->getType(), Temporary: OrigOp.get(), BoundToLvalueReference: true);
14465	} else if (isa<ObjCSelectorExpr>(Val: op)) {
14466	return Context.getPointerType(T: op->getType());
14467	} else if (lval == Expr::LV_MemberFunction) {
14468	// If it's an instance method, make a member pointer.
14469	// The expression must have exactly the form &A::foo.
14470
14471	// If the underlying expression isn't a decl ref, give up.
14472	if (!isa<DeclRefExpr>(Val: op)) {
14473	Diag(Loc: OpLoc, DiagID: diag::err_invalid_form_pointer_member_function)
14474	<< OrigOp.get()->getSourceRange();
14475	return QualType();
14476	}
14477	DeclRefExpr *DRE = cast<DeclRefExpr>(Val: op);
14478	CXXMethodDecl *MD = cast<CXXMethodDecl>(Val: DRE->getDecl());
14479
14480	CheckUseOfCXXMethodAsAddressOfOperand(OpLoc, Op: OrigOp.get(), MD);
14481	QualType MPTy = Context.getMemberPointerType(
14482	T: op->getType(), Qualifier: DRE->getQualifier(), Cls: MD->getParent());
14483
14484	if (getLangOpts().PointerAuthCalls && MD->isVirtual() &&
14485	!isUnevaluatedContext() && !MPTy->isDependentType()) {
14486	// When pointer authentication is enabled, argument and return types of
14487	// vitual member functions must be complete. This is because vitrual
14488	// member function pointers are implemented using virtual dispatch
14489	// thunks and the thunks cannot be emitted if the argument or return
14490	// types are incomplete.
14491	auto ReturnOrParamTypeIsIncomplete = [&](QualType T,
14492	SourceLocation DeclRefLoc,
14493	SourceLocation RetArgTypeLoc) {
14494	if (RequireCompleteType(Loc: DeclRefLoc, T, DiagID: diag::err_incomplete_type)) {
14495	Diag(Loc: DeclRefLoc,
14496	DiagID: diag::note_ptrauth_virtual_function_pointer_incomplete_arg_ret);
14497	Diag(Loc: RetArgTypeLoc,
14498	DiagID: diag::note_ptrauth_virtual_function_incomplete_arg_ret_type)
14499	<< T;
14500	return true;
14501	}
14502	return false;
14503	};
14504	QualType RetTy = MD->getReturnType();
14505	bool IsIncomplete =
14506	!RetTy->isVoidType() &&
14507	ReturnOrParamTypeIsIncomplete(
14508	RetTy, OpLoc, MD->getReturnTypeSourceRange().getBegin());
14509	for (auto *PVD : MD->parameters())
14510	IsIncomplete |= ReturnOrParamTypeIsIncomplete(PVD->getType(), OpLoc,
14511	PVD->getBeginLoc());
14512	if (IsIncomplete)
14513	return QualType();
14514	}
14515
14516	// Under the MS ABI, lock down the inheritance model now.
14517	if (Context.getTargetInfo().getCXXABI().isMicrosoft())
14518	(void)isCompleteType(Loc: OpLoc, T: MPTy);
14519	return MPTy;
14520	} else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) {
14521	// C99 6.5.3.2p1
14522	// The operand must be either an l-value or a function designator
14523	if (!op->getType()->isFunctionType()) {
14524	// Use a special diagnostic for loads from property references.
14525	if (isa<PseudoObjectExpr>(Val: op)) {
14526	AddressOfError = AO_Property_Expansion;
14527	} else {
14528	Diag(Loc: OpLoc, DiagID: diag::err_typecheck_invalid_lvalue_addrof)
14529	<< op->getType() << op->getSourceRange();
14530	return QualType();
14531	}
14532	} else if (const auto *DRE = dyn_cast<DeclRefExpr>(Val: op)) {
14533	if (const auto *MD = dyn_cast_or_null<CXXMethodDecl>(Val: DRE->getDecl()))
14534	CheckUseOfCXXMethodAsAddressOfOperand(OpLoc, Op: OrigOp.get(), MD);
14535	}
14536
14537	} else if (op->getObjectKind() == OK_BitField) { // C99 6.5.3.2p1
14538	// The operand cannot be a bit-field
14539	AddressOfError = AO_Bit_Field;
14540	} else if (op->getObjectKind() == OK_VectorComponent) {
14541	// The operand cannot be an element of a vector
14542	AddressOfError = AO_Vector_Element;
14543	} else if (op->getObjectKind() == OK_MatrixComponent) {
14544	// The operand cannot be an element of a matrix.
14545	AddressOfError = AO_Matrix_Element;
14546	} else if (dcl) { // C99 6.5.3.2p1
14547	// We have an lvalue with a decl. Make sure the decl is not declared
14548	// with the register storage-class specifier.
14549	if (const VarDecl *vd = dyn_cast<VarDecl>(Val: dcl)) {
14550	// in C++ it is not error to take address of a register
14551	// variable (c++03 7.1.1P3)
14552	if (vd->getStorageClass() == SC_Register &&
14553	!getLangOpts().CPlusPlus) {
14554	AddressOfError = AO_Register_Variable;
14555	}
14556	} else if (isa<MSPropertyDecl>(Val: dcl)) {
14557	AddressOfError = AO_Property_Expansion;
14558	} else if (isa<FunctionTemplateDecl>(Val: dcl)) {
14559	return Context.OverloadTy;
14560	} else if (isa<FieldDecl>(Val: dcl) || isa<IndirectFieldDecl>(Val: dcl)) {
14561	// Okay: we can take the address of a field.
14562	// Could be a pointer to member, though, if there is an explicit
14563	// scope qualifier for the class.
14564
14565	// [C++26] [expr.prim.id.general]
14566	// If an id-expression E denotes a non-static non-type member
14567	// of some class C [...] and if E is a qualified-id, E is
14568	// not the un-parenthesized operand of the unary & operator [...]
14569	// the id-expression is transformed into a class member access expression.
14570	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: op);
14571	DRE && DRE->getQualifier() && !isa<ParenExpr>(Val: OrigOp.get())) {
14572	DeclContext *Ctx = dcl->getDeclContext();
14573	if (Ctx && Ctx->isRecord()) {
14574	if (dcl->getType()->isReferenceType()) {
14575	Diag(Loc: OpLoc,
14576	DiagID: diag::err_cannot_form_pointer_to_member_of_reference_type)
14577	<< dcl->getDeclName() << dcl->getType();
14578	return QualType();
14579	}
14580
14581	while (cast<RecordDecl>(Val: Ctx)->isAnonymousStructOrUnion())
14582	Ctx = Ctx->getParent();
14583
14584	QualType MPTy = Context.getMemberPointerType(
14585	T: op->getType(), Qualifier: DRE->getQualifier(), Cls: cast<CXXRecordDecl>(Val: Ctx));
14586	// Under the MS ABI, lock down the inheritance model now.
14587	if (Context.getTargetInfo().getCXXABI().isMicrosoft())
14588	(void)isCompleteType(Loc: OpLoc, T: MPTy);
14589	return MPTy;
14590	}
14591	}
14592	} else if (!isa<FunctionDecl, NonTypeTemplateParmDecl, BindingDecl,
14593	MSGuidDecl, UnnamedGlobalConstantDecl>(Val: dcl))
14594	llvm_unreachable("Unknown/unexpected decl type");
14595	}
14596
14597	if (AddressOfError != AO_No_Error) {
14598	diagnoseAddressOfInvalidType(S&: *this, Loc: OpLoc, E: op, Type: AddressOfError);
14599	return QualType();
14600	}
14601
14602	if (lval == Expr::LV_IncompleteVoidType) {
14603	// Taking the address of a void variable is technically illegal, but we
14604	// allow it in cases which are otherwise valid.
14605	// Example: "extern void x; void* y = &x;".
14606	Diag(Loc: OpLoc, DiagID: diag::ext_typecheck_addrof_void) << op->getSourceRange();
14607	}
14608
14609	// If the operand has type "type", the result has type "pointer to type".
14610	if (op->getType()->isObjCObjectType())
14611	return Context.getObjCObjectPointerType(OIT: op->getType());
14612
14613	// Cannot take the address of WebAssembly references or tables.
14614	if (Context.getTargetInfo().getTriple().isWasm()) {
14615	QualType OpTy = op->getType();
14616	if (OpTy.isWebAssemblyReferenceType()) {
14617	Diag(Loc: OpLoc, DiagID: diag::err_wasm_ca_reference)
14618	<< 1 << OrigOp.get()->getSourceRange();
14619	return QualType();
14620	}
14621	if (OpTy->isWebAssemblyTableType()) {
14622	Diag(Loc: OpLoc, DiagID: diag::err_wasm_table_pr)
14623	<< 1 << OrigOp.get()->getSourceRange();
14624	return QualType();
14625	}
14626	}
14627
14628	CheckAddressOfPackedMember(rhs: op);
14629
14630	return Context.getPointerType(T: op->getType());
14631	}
14632
14633	static void RecordModifiableNonNullParam(Sema &S, const Expr *Exp) {
14634	const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: Exp);
14635	if (!DRE)
14636	return;
14637	const Decl *D = DRE->getDecl();
14638	if (!D)
14639	return;
14640	const ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Val: D);
14641	if (!Param)
14642	return;
14643	if (const FunctionDecl* FD = dyn_cast<FunctionDecl>(Val: Param->getDeclContext()))
14644	if (!FD->hasAttr<NonNullAttr>() && !Param->hasAttr<NonNullAttr>())
14645	return;
14646	if (FunctionScopeInfo *FD = S.getCurFunction())
14647	FD->ModifiedNonNullParams.insert(Ptr: Param);
14648	}
14649
14650	/// CheckIndirectionOperand - Type check unary indirection (prefix '*').
14651	static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK,
14652	SourceLocation OpLoc,
14653	bool IsAfterAmp = false) {
14654	ExprResult ConvResult = S.UsualUnaryConversions(E: Op);
14655	if (ConvResult.isInvalid())
14656	return QualType();
14657	Op = ConvResult.get();
14658	QualType OpTy = Op->getType();
14659	QualType Result;
14660
14661	if (isa<CXXReinterpretCastExpr>(Val: Op)) {
14662	QualType OpOrigType = Op->IgnoreParenCasts()->getType();
14663	S.CheckCompatibleReinterpretCast(SrcType: OpOrigType, DestType: OpTy, /*IsDereference*/true,
14664	Range: Op->getSourceRange());
14665	}
14666
14667	if (const PointerType *PT = OpTy->getAs<PointerType>())
14668	{
14669	Result = PT->getPointeeType();
14670	}
14671	else if (const ObjCObjectPointerType *OPT =
14672	OpTy->getAs<ObjCObjectPointerType>())
14673	Result = OPT->getPointeeType();
14674	else {
14675	ExprResult PR = S.CheckPlaceholderExpr(E: Op);
14676	if (PR.isInvalid()) return QualType();
14677	if (PR.get() != Op)
14678	return CheckIndirectionOperand(S, Op: PR.get(), VK, OpLoc);
14679	}
14680
14681	if (Result.isNull()) {
14682	S.Diag(Loc: OpLoc, DiagID: diag::err_typecheck_indirection_requires_pointer)
14683	<< OpTy << Op->getSourceRange();
14684	return QualType();
14685	}
14686
14687	if (Result->isVoidType()) {
14688	// C++ [expr.unary.op]p1:
14689	// [...] the expression to which [the unary * operator] is applied shall
14690	// be a pointer to an object type, or a pointer to a function type
14691	LangOptions LO = S.getLangOpts();
14692	if (LO.CPlusPlus)
14693	S.Diag(Loc: OpLoc, DiagID: diag::err_typecheck_indirection_through_void_pointer_cpp)
14694	<< OpTy << Op->getSourceRange();
14695	else if (!(LO.C99 && IsAfterAmp) && !S.isUnevaluatedContext())
14696	S.Diag(Loc: OpLoc, DiagID: diag::ext_typecheck_indirection_through_void_pointer)
14697	<< OpTy << Op->getSourceRange();
14698	}
14699
14700	// Dereferences are usually l-values...
14701	VK = VK_LValue;
14702
14703	// ...except that certain expressions are never l-values in C.
14704	if (!S.getLangOpts().CPlusPlus && Result.isCForbiddenLValueType())
14705	VK = VK_PRValue;
14706
14707	return Result;
14708	}
14709
14710	BinaryOperatorKind Sema::ConvertTokenKindToBinaryOpcode(tok::TokenKind Kind) {
14711	BinaryOperatorKind Opc;
14712	switch (Kind) {
14713	default: llvm_unreachable("Unknown binop!");
14714	case tok::periodstar: Opc = BO_PtrMemD; break;
14715	case tok::arrowstar: Opc = BO_PtrMemI; break;
14716	case tok::star: Opc = BO_Mul; break;
14717	case tok::slash: Opc = BO_Div; break;
14718	case tok::percent: Opc = BO_Rem; break;
14719	case tok::plus: Opc = BO_Add; break;
14720	case tok::minus: Opc = BO_Sub; break;
14721	case tok::lessless: Opc = BO_Shl; break;
14722	case tok::greatergreater: Opc = BO_Shr; break;
14723	case tok::lessequal: Opc = BO_LE; break;
14724	case tok::less: Opc = BO_LT; break;
14725	case tok::greaterequal: Opc = BO_GE; break;
14726	case tok::greater: Opc = BO_GT; break;
14727	case tok::exclaimequal: Opc = BO_NE; break;
14728	case tok::equalequal: Opc = BO_EQ; break;
14729	case tok::spaceship: Opc = BO_Cmp; break;
14730	case tok::amp: Opc = BO_And; break;
14731	case tok::caret: Opc = BO_Xor; break;
14732	case tok::pipe: Opc = BO_Or; break;
14733	case tok::ampamp: Opc = BO_LAnd; break;
14734	case tok::pipepipe: Opc = BO_LOr; break;
14735	case tok::equal: Opc = BO_Assign; break;
14736	case tok::starequal: Opc = BO_MulAssign; break;
14737	case tok::slashequal: Opc = BO_DivAssign; break;
14738	case tok::percentequal: Opc = BO_RemAssign; break;
14739	case tok::plusequal: Opc = BO_AddAssign; break;
14740	case tok::minusequal: Opc = BO_SubAssign; break;
14741	case tok::lesslessequal: Opc = BO_ShlAssign; break;
14742	case tok::greatergreaterequal: Opc = BO_ShrAssign; break;
14743	case tok::ampequal: Opc = BO_AndAssign; break;
14744	case tok::caretequal: Opc = BO_XorAssign; break;
14745	case tok::pipeequal: Opc = BO_OrAssign; break;
14746	case tok::comma: Opc = BO_Comma; break;
14747	}
14748	return Opc;
14749	}
14750
14751	static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode(
14752	tok::TokenKind Kind) {
14753	UnaryOperatorKind Opc;
14754	switch (Kind) {
14755	default: llvm_unreachable("Unknown unary op!");
14756	case tok::plusplus: Opc = UO_PreInc; break;
14757	case tok::minusminus: Opc = UO_PreDec; break;
14758	case tok::amp: Opc = UO_AddrOf; break;
14759	case tok::star: Opc = UO_Deref; break;
14760	case tok::plus: Opc = UO_Plus; break;
14761	case tok::minus: Opc = UO_Minus; break;
14762	case tok::tilde: Opc = UO_Not; break;
14763	case tok::exclaim: Opc = UO_LNot; break;
14764	case tok::kw___real: Opc = UO_Real; break;
14765	case tok::kw___imag: Opc = UO_Imag; break;
14766	case tok::kw___extension__: Opc = UO_Extension; break;
14767	}
14768	return Opc;
14769	}
14770
14771	const FieldDecl *
14772	Sema::getSelfAssignmentClassMemberCandidate(const ValueDecl *SelfAssigned) {
14773	// Explore the case for adding 'this->' to the LHS of a self assignment, very
14774	// common for setters.
14775	// struct A {
14776	// int X;
14777	// -void setX(int X) { X = X; }
14778	// +void setX(int X) { this->X = X; }
14779	// };
14780
14781	// Only consider parameters for self assignment fixes.
14782	if (!isa<ParmVarDecl>(Val: SelfAssigned))
14783	return nullptr;
14784	const auto *Method =
14785	dyn_cast_or_null<CXXMethodDecl>(Val: getCurFunctionDecl(AllowLambda: true));
14786	if (!Method)
14787	return nullptr;
14788
14789	const CXXRecordDecl *Parent = Method->getParent();
14790	// In theory this is fixable if the lambda explicitly captures this, but
14791	// that's added complexity that's rarely going to be used.
14792	if (Parent->isLambda())
14793	return nullptr;
14794
14795	// FIXME: Use an actual Lookup operation instead of just traversing fields
14796	// in order to get base class fields.
14797	auto Field =
14798	llvm::find_if(Range: Parent->fields(),
14799	P: [Name(SelfAssigned->getDeclName())](const FieldDecl *F) {
14800	return F->getDeclName() == Name;
14801	});
14802	return (Field != Parent->field_end()) ? *Field : nullptr;
14803	}
14804
14805	/// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself.
14806	/// This warning suppressed in the event of macro expansions.
14807	static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr,
14808	SourceLocation OpLoc, bool IsBuiltin) {
14809	if (S.inTemplateInstantiation())
14810	return;
14811	if (S.isUnevaluatedContext())
14812	return;
14813	if (OpLoc.isInvalid() || OpLoc.isMacroID())
14814	return;
14815	LHSExpr = LHSExpr->IgnoreParenImpCasts();
14816	RHSExpr = RHSExpr->IgnoreParenImpCasts();
14817	const DeclRefExpr *LHSDeclRef = dyn_cast<DeclRefExpr>(Val: LHSExpr);
14818	const DeclRefExpr *RHSDeclRef = dyn_cast<DeclRefExpr>(Val: RHSExpr);
14819	if (!LHSDeclRef || !RHSDeclRef ||
14820	LHSDeclRef->getLocation().isMacroID() ||
14821	RHSDeclRef->getLocation().isMacroID())
14822	return;
14823	const ValueDecl *LHSDecl =
14824	cast<ValueDecl>(Val: LHSDeclRef->getDecl()->getCanonicalDecl());
14825	const ValueDecl *RHSDecl =
14826	cast<ValueDecl>(Val: RHSDeclRef->getDecl()->getCanonicalDecl());
14827	if (LHSDecl != RHSDecl)
14828	return;
14829	if (LHSDecl->getType().isVolatileQualified())
14830	return;
14831	if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>())
14832	if (RefTy->getPointeeType().isVolatileQualified())
14833	return;
14834
14835	auto Diag = S.Diag(Loc: OpLoc, DiagID: IsBuiltin ? diag::warn_self_assignment_builtin
14836	: diag::warn_self_assignment_overloaded)
14837	<< LHSDeclRef->getType() << LHSExpr->getSourceRange()
14838	<< RHSExpr->getSourceRange();
14839	if (const FieldDecl *SelfAssignField =
14840	S.getSelfAssignmentClassMemberCandidate(SelfAssigned: RHSDecl))
14841	Diag << 1 << SelfAssignField
14842	<< FixItHint::CreateInsertion(InsertionLoc: LHSDeclRef->getBeginLoc(), Code: "this->");
14843	else
14844	Diag << 0;
14845	}
14846
14847	/// Check if a bitwise-& is performed on an Objective-C pointer. This
14848	/// is usually indicative of introspection within the Objective-C pointer.
14849	static void checkObjCPointerIntrospection(Sema &S, ExprResult &L, ExprResult &R,
14850	SourceLocation OpLoc) {
14851	if (!S.getLangOpts().ObjC)
14852	return;
14853
14854	const Expr *ObjCPointerExpr = nullptr, *OtherExpr = nullptr;
14855	const Expr *LHS = L.get();
14856	const Expr *RHS = R.get();
14857
14858	if (LHS->IgnoreParenCasts()->getType()->isObjCObjectPointerType()) {
14859	ObjCPointerExpr = LHS;
14860	OtherExpr = RHS;
14861	}
14862	else if (RHS->IgnoreParenCasts()->getType()->isObjCObjectPointerType()) {
14863	ObjCPointerExpr = RHS;
14864	OtherExpr = LHS;
14865	}
14866
14867	// This warning is deliberately made very specific to reduce false
14868	// positives with logic that uses '&' for hashing. This logic mainly
14869	// looks for code trying to introspect into tagged pointers, which
14870	// code should generally never do.
14871	if (ObjCPointerExpr && isa<IntegerLiteral>(Val: OtherExpr->IgnoreParenCasts())) {
14872	unsigned Diag = diag::warn_objc_pointer_masking;
14873	// Determine if we are introspecting the result of performSelectorXXX.
14874	const Expr *Ex = ObjCPointerExpr->IgnoreParenCasts();
14875	// Special case messages to -performSelector and friends, which
14876	// can return non-pointer values boxed in a pointer value.
14877	// Some clients may wish to silence warnings in this subcase.
14878	if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(Val: Ex)) {
14879	Selector S = ME->getSelector();
14880	StringRef SelArg0 = S.getNameForSlot(argIndex: 0);
14881	if (SelArg0.starts_with(Prefix: "performSelector"))
14882	Diag = diag::warn_objc_pointer_masking_performSelector;
14883	}
14884
14885	S.Diag(Loc: OpLoc, DiagID: Diag)
14886	<< ObjCPointerExpr->getSourceRange();
14887	}
14888	}
14889
14890	// This helper function promotes a binary operator's operands (which are of a
14891	// half vector type) to a vector of floats and then truncates the result to
14892	// a vector of either half or short.
14893	static ExprResult convertHalfVecBinOp(Sema &S, ExprResult LHS, ExprResult RHS,
14894	BinaryOperatorKind Opc, QualType ResultTy,
14895	ExprValueKind VK, ExprObjectKind OK,
14896	bool IsCompAssign, SourceLocation OpLoc,
14897	FPOptionsOverride FPFeatures) {
14898	auto &Context = S.getASTContext();
14899	assert((isVector(ResultTy, Context.HalfTy) ||
14900	isVector(ResultTy, Context.ShortTy)) &&
14901	"Result must be a vector of half or short");
14902	assert(isVector(LHS.get()->getType(), Context.HalfTy) &&
14903	isVector(RHS.get()->getType(), Context.HalfTy) &&
14904	"both operands expected to be a half vector");
14905
14906	RHS = convertVector(E: RHS.get(), ElementType: Context.FloatTy, S);
14907	QualType BinOpResTy = RHS.get()->getType();
14908
14909	// If Opc is a comparison, ResultType is a vector of shorts. In that case,
14910	// change BinOpResTy to a vector of ints.
14911	if (isVector(QT: ResultTy, ElementType: Context.ShortTy))
14912	BinOpResTy = S.GetSignedVectorType(V: BinOpResTy);
14913
14914	if (IsCompAssign)
14915	return CompoundAssignOperator::Create(C: Context, lhs: LHS.get(), rhs: RHS.get(), opc: Opc,
14916	ResTy: ResultTy, VK, OK, opLoc: OpLoc, FPFeatures,
14917	CompLHSType: BinOpResTy, CompResultType: BinOpResTy);
14918
14919	LHS = convertVector(E: LHS.get(), ElementType: Context.FloatTy, S);
14920	auto *BO = BinaryOperator::Create(C: Context, lhs: LHS.get(), rhs: RHS.get(), opc: Opc,
14921	ResTy: BinOpResTy, VK, OK, opLoc: OpLoc, FPFeatures);
14922	return convertVector(E: BO, ElementType: ResultTy->castAs<VectorType>()->getElementType(), S);
14923	}
14924
14925	/// Returns true if conversion between vectors of halfs and vectors of floats
14926	/// is needed.
14927	static bool needsConversionOfHalfVec(bool OpRequiresConversion, ASTContext &Ctx,
14928	Expr *E0, Expr *E1 = nullptr) {
14929	if (!OpRequiresConversion || Ctx.getLangOpts().NativeHalfType ||
14930	Ctx.getTargetInfo().useFP16ConversionIntrinsics())
14931	return false;
14932
14933	auto HasVectorOfHalfType = [&Ctx](Expr *E) {
14934	QualType Ty = E->IgnoreImplicit()->getType();
14935
14936	// Don't promote half precision neon vectors like float16x4_t in arm_neon.h
14937	// to vectors of floats. Although the element type of the vectors is __fp16,
14938	// the vectors shouldn't be treated as storage-only types. See the
14939	// discussion here: https://reviews.llvm.org/rG825235c140e7
14940	if (const VectorType *VT = Ty->getAs<VectorType>()) {
14941	if (VT->getVectorKind() == VectorKind::Neon)
14942	return false;
14943	return VT->getElementType().getCanonicalType() == Ctx.HalfTy;
14944	}
14945	return false;
14946	};
14947
14948	return HasVectorOfHalfType(E0) && (!E1 || HasVectorOfHalfType(E1));
14949	}
14950
14951	ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc,
14952	BinaryOperatorKind Opc, Expr *LHSExpr,
14953	Expr *RHSExpr, bool ForFoldExpression) {
14954	if (getLangOpts().CPlusPlus11 && isa<InitListExpr>(Val: RHSExpr)) {
14955	// The syntax only allows initializer lists on the RHS of assignment,
14956	// so we don't need to worry about accepting invalid code for
14957	// non-assignment operators.
14958	// C++11 5.17p9:
14959	// The meaning of x = {v} [...] is that of x = T(v) [...]. The meaning
14960	// of x = {} is x = T().
14961	InitializationKind Kind = InitializationKind::CreateDirectList(
14962	InitLoc: RHSExpr->getBeginLoc(), LBraceLoc: RHSExpr->getBeginLoc(), RBraceLoc: RHSExpr->getEndLoc());
14963	InitializedEntity Entity =
14964	InitializedEntity::InitializeTemporary(Type: LHSExpr->getType());
14965	InitializationSequence InitSeq(*this, Entity, Kind, RHSExpr);
14966	ExprResult Init = InitSeq.Perform(S&: *this, Entity, Kind, Args: RHSExpr);
14967	if (Init.isInvalid())
14968	return Init;
14969	RHSExpr = Init.get();
14970	}
14971
14972	ExprResult LHS = LHSExpr, RHS = RHSExpr;
14973	QualType ResultTy; // Result type of the binary operator.
14974	// The following two variables are used for compound assignment operators
14975	QualType CompLHSTy; // Type of LHS after promotions for computation
14976	QualType CompResultTy; // Type of computation result
14977	ExprValueKind VK = VK_PRValue;
14978	ExprObjectKind OK = OK_Ordinary;
14979	bool ConvertHalfVec = false;
14980
14981	if (!LHS.isUsable() || !RHS.isUsable())
14982	return ExprError();
14983
14984	if (getLangOpts().OpenCL) {
14985	QualType LHSTy = LHSExpr->getType();
14986	QualType RHSTy = RHSExpr->getType();
14987	// OpenCLC v2.0 s6.13.11.1 allows atomic variables to be initialized by
14988	// the ATOMIC_VAR_INIT macro.
14989	if (LHSTy->isAtomicType() || RHSTy->isAtomicType()) {
14990	SourceRange SR(LHSExpr->getBeginLoc(), RHSExpr->getEndLoc());
14991	if (BO_Assign == Opc)
14992	Diag(Loc: OpLoc, DiagID: diag::err_opencl_atomic_init) << 0 << SR;
14993	else
14994	ResultTy = InvalidOperands(Loc: OpLoc, LHS, RHS);
14995	return ExprError();
14996	}
14997
14998	// OpenCL special types - image, sampler, pipe, and blocks are to be used
14999	// only with a builtin functions and therefore should be disallowed here.
15000	if (LHSTy->isImageType() || RHSTy->isImageType() ||
15001	LHSTy->isSamplerT() || RHSTy->isSamplerT() ||
15002	LHSTy->isPipeType() || RHSTy->isPipeType() ||
15003	LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) {
15004	ResultTy = InvalidOperands(Loc: OpLoc, LHS, RHS);
15005	return ExprError();
15006	}
15007	}
15008
15009	checkTypeSupport(Ty: LHSExpr->getType(), Loc: OpLoc, /*ValueDecl*/ D: nullptr);
15010	checkTypeSupport(Ty: RHSExpr->getType(), Loc: OpLoc, /*ValueDecl*/ D: nullptr);
15011
15012	switch (Opc) {
15013	case BO_Assign:
15014	ResultTy = CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: QualType(), Opc);
15015	if (getLangOpts().CPlusPlus &&
15016	LHS.get()->getObjectKind() != OK_ObjCProperty) {
15017	VK = LHS.get()->getValueKind();
15018	OK = LHS.get()->getObjectKind();
15019	}
15020	if (!ResultTy.isNull()) {
15021	DiagnoseSelfAssignment(S&: *this, LHSExpr: LHS.get(), RHSExpr: RHS.get(), OpLoc, IsBuiltin: true);
15022	DiagnoseSelfMove(LHSExpr: LHS.get(), RHSExpr: RHS.get(), OpLoc);
15023
15024	// Avoid copying a block to the heap if the block is assigned to a local
15025	// auto variable that is declared in the same scope as the block. This
15026	// optimization is unsafe if the local variable is declared in an outer
15027	// scope. For example:
15028	//
15029	// BlockTy b;
15030	// {
15031	// b = ^{...};
15032	// }
15033	// // It is unsafe to invoke the block here if it wasn't copied to the
15034	// // heap.
15035	// b();
15036
15037	if (auto *BE = dyn_cast<BlockExpr>(Val: RHS.get()->IgnoreParens()))
15038	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: LHS.get()->IgnoreParens()))
15039	if (auto *VD = dyn_cast<VarDecl>(Val: DRE->getDecl()))
15040	if (VD->hasLocalStorage() && getCurScope()->isDeclScope(D: VD))
15041	BE->getBlockDecl()->setCanAvoidCopyToHeap();
15042
15043	if (LHS.get()->getType().hasNonTrivialToPrimitiveCopyCUnion())
15044	checkNonTrivialCUnion(QT: LHS.get()->getType(), Loc: LHS.get()->getExprLoc(),
15045	UseContext: NonTrivialCUnionContext::Assignment, NonTrivialKind: NTCUK_Copy);
15046	}
15047	RecordModifiableNonNullParam(S&: *this, Exp: LHS.get());
15048	break;
15049	case BO_PtrMemD:
15050	case BO_PtrMemI:
15051	ResultTy = CheckPointerToMemberOperands(LHS, RHS, VK, OpLoc,
15052	isIndirect: Opc == BO_PtrMemI);
15053	break;
15054	case BO_Mul:
15055	case BO_Div:
15056	ConvertHalfVec = true;
15057	ResultTy = CheckMultiplyDivideOperands(LHS, RHS, Loc: OpLoc, IsCompAssign: false,
15058	IsDiv: Opc == BO_Div);
15059	break;
15060	case BO_Rem:
15061	ResultTy = CheckRemainderOperands(LHS, RHS, Loc: OpLoc);
15062	break;
15063	case BO_Add:
15064	ConvertHalfVec = true;
15065	ResultTy = CheckAdditionOperands(LHS, RHS, Loc: OpLoc, Opc);
15066	break;
15067	case BO_Sub:
15068	ConvertHalfVec = true;
15069	ResultTy = CheckSubtractionOperands(LHS, RHS, Loc: OpLoc);
15070	break;
15071	case BO_Shl:
15072	case BO_Shr:
15073	ResultTy = CheckShiftOperands(LHS, RHS, Loc: OpLoc, Opc);
15074	break;
15075	case BO_LE:
15076	case BO_LT:
15077	case BO_GE:
15078	case BO_GT:
15079	ConvertHalfVec = true;
15080	ResultTy = CheckCompareOperands(LHS, RHS, Loc: OpLoc, Opc);
15081
15082	if (const auto *BI = dyn_cast<BinaryOperator>(Val: LHSExpr);
15083	!ForFoldExpression && BI && BI->isComparisonOp())
15084	Diag(Loc: OpLoc, DiagID: diag::warn_consecutive_comparison)
15085	<< BI->getOpcodeStr() << BinaryOperator::getOpcodeStr(Op: Opc);
15086
15087	break;
15088	case BO_EQ:
15089	case BO_NE:
15090	ConvertHalfVec = true;
15091	ResultTy = CheckCompareOperands(LHS, RHS, Loc: OpLoc, Opc);
15092	break;
15093	case BO_Cmp:
15094	ConvertHalfVec = true;
15095	ResultTy = CheckCompareOperands(LHS, RHS, Loc: OpLoc, Opc);
15096	assert(ResultTy.isNull() || ResultTy->getAsCXXRecordDecl());
15097	break;
15098	case BO_And:
15099	checkObjCPointerIntrospection(S&: *this, L&: LHS, R&: RHS, OpLoc);
15100	[[fallthrough]];
15101	case BO_Xor:
15102	case BO_Or:
15103	ResultTy = CheckBitwiseOperands(LHS, RHS, Loc: OpLoc, Opc);
15104	break;
15105	case BO_LAnd:
15106	case BO_LOr:
15107	ConvertHalfVec = true;
15108	ResultTy = CheckLogicalOperands(LHS, RHS, Loc: OpLoc, Opc);
15109	break;
15110	case BO_MulAssign:
15111	case BO_DivAssign:
15112	ConvertHalfVec = true;
15113	CompResultTy = CheckMultiplyDivideOperands(LHS, RHS, Loc: OpLoc, IsCompAssign: true,
15114	IsDiv: Opc == BO_DivAssign);
15115	CompLHSTy = CompResultTy;
15116	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15117	ResultTy =
15118	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15119	break;
15120	case BO_RemAssign:
15121	CompResultTy = CheckRemainderOperands(LHS, RHS, Loc: OpLoc, IsCompAssign: true);
15122	CompLHSTy = CompResultTy;
15123	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15124	ResultTy =
15125	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15126	break;
15127	case BO_AddAssign:
15128	ConvertHalfVec = true;
15129	CompResultTy = CheckAdditionOperands(LHS, RHS, Loc: OpLoc, Opc, CompLHSTy: &CompLHSTy);
15130	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15131	ResultTy =
15132	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15133	break;
15134	case BO_SubAssign:
15135	ConvertHalfVec = true;
15136	CompResultTy = CheckSubtractionOperands(LHS, RHS, Loc: OpLoc, CompLHSTy: &CompLHSTy);
15137	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15138	ResultTy =
15139	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15140	break;
15141	case BO_ShlAssign:
15142	case BO_ShrAssign:
15143	CompResultTy = CheckShiftOperands(LHS, RHS, Loc: OpLoc, Opc, IsCompAssign: true);
15144	CompLHSTy = CompResultTy;
15145	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15146	ResultTy =
15147	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15148	break;
15149	case BO_AndAssign:
15150	case BO_OrAssign: // fallthrough
15151	DiagnoseSelfAssignment(S&: *this, LHSExpr: LHS.get(), RHSExpr: RHS.get(), OpLoc, IsBuiltin: true);
15152	[[fallthrough]];
15153	case BO_XorAssign:
15154	CompResultTy = CheckBitwiseOperands(LHS, RHS, Loc: OpLoc, Opc);
15155	CompLHSTy = CompResultTy;
15156	if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
15157	ResultTy =
15158	CheckAssignmentOperands(LHSExpr: LHS.get(), RHS, Loc: OpLoc, CompoundType: CompResultTy, Opc);
15159	break;
15160	case BO_Comma:
15161	ResultTy = CheckCommaOperands(S&: *this, LHS, RHS, Loc: OpLoc);
15162	if (getLangOpts().CPlusPlus && !RHS.isInvalid()) {
15163	VK = RHS.get()->getValueKind();
15164	OK = RHS.get()->getObjectKind();
15165	}
15166	break;
15167	}
15168	if (ResultTy.isNull() || LHS.isInvalid() || RHS.isInvalid())
15169	return ExprError();
15170
15171	// Some of the binary operations require promoting operands of half vector to
15172	// float vectors and truncating the result back to half vector. For now, we do
15173	// this only when HalfArgsAndReturn is set (that is, when the target is arm or
15174	// arm64).
15175	assert(
15176	(Opc == BO_Comma || isVector(RHS.get()->getType(), Context.HalfTy) ==
15177	isVector(LHS.get()->getType(), Context.HalfTy)) &&
15178	"both sides are half vectors or neither sides are");
15179	ConvertHalfVec =
15180	needsConversionOfHalfVec(OpRequiresConversion: ConvertHalfVec, Ctx&: Context, E0: LHS.get(), E1: RHS.get());
15181
15182	// Check for array bounds violations for both sides of the BinaryOperator
15183	CheckArrayAccess(E: LHS.get());
15184	CheckArrayAccess(E: RHS.get());
15185
15186	if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(Val: LHS.get()->IgnoreParenCasts())) {
15187	NamedDecl *ObjectSetClass = LookupSingleName(S: TUScope,
15188	Name: &Context.Idents.get(Name: "object_setClass"),
15189	Loc: SourceLocation(), NameKind: LookupOrdinaryName);
15190	if (ObjectSetClass && isa<ObjCIsaExpr>(Val: LHS.get())) {
15191	SourceLocation RHSLocEnd = getLocForEndOfToken(Loc: RHS.get()->getEndLoc());
15192	Diag(Loc: LHS.get()->getExprLoc(), DiagID: diag::warn_objc_isa_assign)
15193	<< FixItHint::CreateInsertion(InsertionLoc: LHS.get()->getBeginLoc(),
15194	Code: "object_setClass(")
15195	<< FixItHint::CreateReplacement(RemoveRange: SourceRange(OISA->getOpLoc(), OpLoc),
15196	Code: ",")
15197	<< FixItHint::CreateInsertion(InsertionLoc: RHSLocEnd, Code: ")");
15198	}
15199	else
15200	Diag(Loc: LHS.get()->getExprLoc(), DiagID: diag::warn_objc_isa_assign);
15201	}
15202	else if (const ObjCIvarRefExpr *OIRE =
15203	dyn_cast<ObjCIvarRefExpr>(Val: LHS.get()->IgnoreParenCasts()))
15204	DiagnoseDirectIsaAccess(S&: *this, OIRE, AssignLoc: OpLoc, RHS: RHS.get());
15205
15206	// Opc is not a compound assignment if CompResultTy is null.
15207	if (CompResultTy.isNull()) {
15208	if (ConvertHalfVec)
15209	return convertHalfVecBinOp(S&: *this, LHS, RHS, Opc, ResultTy, VK, OK, IsCompAssign: false,
15210	OpLoc, FPFeatures: CurFPFeatureOverrides());
15211	return BinaryOperator::Create(C: Context, lhs: LHS.get(), rhs: RHS.get(), opc: Opc, ResTy: ResultTy,
15212	VK, OK, opLoc: OpLoc, FPFeatures: CurFPFeatureOverrides());
15213	}
15214
15215	// Handle compound assignments.
15216	if (getLangOpts().CPlusPlus && LHS.get()->getObjectKind() !=
15217	OK_ObjCProperty) {
15218	VK = VK_LValue;
15219	OK = LHS.get()->getObjectKind();
15220	}
15221
15222	// The LHS is not converted to the result type for fixed-point compound
15223	// assignment as the common type is computed on demand. Reset the CompLHSTy
15224	// to the LHS type we would have gotten after unary conversions.
15225	if (CompResultTy->isFixedPointType())
15226	CompLHSTy = UsualUnaryConversions(E: LHS.get()).get()->getType();
15227
15228	if (ConvertHalfVec)
15229	return convertHalfVecBinOp(S&: *this, LHS, RHS, Opc, ResultTy, VK, OK, IsCompAssign: true,
15230	OpLoc, FPFeatures: CurFPFeatureOverrides());
15231
15232	return CompoundAssignOperator::Create(
15233	C: Context, lhs: LHS.get(), rhs: RHS.get(), opc: Opc, ResTy: ResultTy, VK, OK, opLoc: OpLoc,
15234	FPFeatures: CurFPFeatureOverrides(), CompLHSType: CompLHSTy, CompResultType: CompResultTy);
15235	}
15236
15237	/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison
15238	/// operators are mixed in a way that suggests that the programmer forgot that
15239	/// comparison operators have higher precedence. The most typical example of
15240	/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1".
15241	static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc,
15242	SourceLocation OpLoc, Expr *LHSExpr,
15243	Expr *RHSExpr) {
15244	BinaryOperator *LHSBO = dyn_cast<BinaryOperator>(Val: LHSExpr);
15245	BinaryOperator *RHSBO = dyn_cast<BinaryOperator>(Val: RHSExpr);
15246
15247	// Check that one of the sides is a comparison operator and the other isn't.
15248	bool isLeftComp = LHSBO && LHSBO->isComparisonOp();
15249	bool isRightComp = RHSBO && RHSBO->isComparisonOp();
15250	if (isLeftComp == isRightComp)
15251	return;
15252
15253	// Bitwise operations are sometimes used as eager logical ops.
15254	// Don't diagnose this.
15255	bool isLeftBitwise = LHSBO && LHSBO->isBitwiseOp();
15256	bool isRightBitwise = RHSBO && RHSBO->isBitwiseOp();
15257	if (isLeftBitwise || isRightBitwise)
15258	return;
15259
15260	SourceRange DiagRange = isLeftComp
15261	? SourceRange(LHSExpr->getBeginLoc(), OpLoc)
15262	: SourceRange(OpLoc, RHSExpr->getEndLoc());
15263	StringRef OpStr = isLeftComp ? LHSBO->getOpcodeStr() : RHSBO->getOpcodeStr();
15264	SourceRange ParensRange =
15265	isLeftComp
15266	? SourceRange(LHSBO->getRHS()->getBeginLoc(), RHSExpr->getEndLoc())
15267	: SourceRange(LHSExpr->getBeginLoc(), RHSBO->getLHS()->getEndLoc());
15268
15269	Self.Diag(Loc: OpLoc, DiagID: diag::warn_precedence_bitwise_rel)
15270	<< DiagRange << BinaryOperator::getOpcodeStr(Op: Opc) << OpStr;
15271	SuggestParentheses(Self, Loc: OpLoc,
15272	Note: Self.PDiag(DiagID: diag::note_precedence_silence) << OpStr,
15273	ParenRange: (isLeftComp ? LHSExpr : RHSExpr)->getSourceRange());
15274	SuggestParentheses(Self, Loc: OpLoc,
15275	Note: Self.PDiag(DiagID: diag::note_precedence_bitwise_first)
15276	<< BinaryOperator::getOpcodeStr(Op: Opc),
15277	ParenRange: ParensRange);
15278	}
15279
15280	/// It accepts a '&&' expr that is inside a '||' one.
15281	/// Emit a diagnostic together with a fixit hint that wraps the '&&' expression
15282	/// in parentheses.
15283	static void
15284	EmitDiagnosticForLogicalAndInLogicalOr(Sema &Self, SourceLocation OpLoc,
15285	BinaryOperator *Bop) {
15286	assert(Bop->getOpcode() == BO_LAnd);
15287	Self.Diag(Loc: Bop->getOperatorLoc(), DiagID: diag::warn_logical_and_in_logical_or)
15288	<< Bop->getSourceRange() << OpLoc;
15289	SuggestParentheses(Self, Loc: Bop->getOperatorLoc(),
15290	Note: Self.PDiag(DiagID: diag::note_precedence_silence)
15291	<< Bop->getOpcodeStr(),
15292	ParenRange: Bop->getSourceRange());
15293	}
15294
15295	/// Look for '&&' in the left hand of a '||' expr.
15296	static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc,
15297	Expr *LHSExpr, Expr *RHSExpr) {
15298	if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(Val: LHSExpr)) {
15299	if (Bop->getOpcode() == BO_LAnd) {
15300	// If it's "string_literal && a || b" don't warn since the precedence
15301	// doesn't matter.
15302	if (!isa<StringLiteral>(Val: Bop->getLHS()->IgnoreParenImpCasts()))
15303	return EmitDiagnosticForLogicalAndInLogicalOr(Self&: S, OpLoc, Bop);
15304	} else if (Bop->getOpcode() == BO_LOr) {
15305	if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Val: Bop->getRHS())) {
15306	// If it's "a || b && string_literal || c" we didn't warn earlier for
15307	// "a || b && string_literal", but warn now.
15308	if (RBop->getOpcode() == BO_LAnd &&
15309	isa<StringLiteral>(Val: RBop->getRHS()->IgnoreParenImpCasts()))
15310	return EmitDiagnosticForLogicalAndInLogicalOr(Self&: S, OpLoc, Bop: RBop);
15311	}
15312	}
15313	}
15314	}
15315
15316	/// Look for '&&' in the right hand of a '||' expr.
15317	static void DiagnoseLogicalAndInLogicalOrRHS(Sema &S, SourceLocation OpLoc,
15318	Expr *LHSExpr, Expr *RHSExpr) {
15319	if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(Val: RHSExpr)) {
15320	if (Bop->getOpcode() == BO_LAnd) {
15321	// If it's "a || b && string_literal" don't warn since the precedence
15322	// doesn't matter.
15323	if (!isa<StringLiteral>(Val: Bop->getRHS()->IgnoreParenImpCasts()))
15324	return EmitDiagnosticForLogicalAndInLogicalOr(Self&: S, OpLoc, Bop);
15325	}
15326	}
15327	}
15328
15329	/// Look for bitwise op in the left or right hand of a bitwise op with
15330	/// lower precedence and emit a diagnostic together with a fixit hint that wraps
15331	/// the '&' expression in parentheses.
15332	static void DiagnoseBitwiseOpInBitwiseOp(Sema &S, BinaryOperatorKind Opc,
15333	SourceLocation OpLoc, Expr *SubExpr) {
15334	if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(Val: SubExpr)) {
15335	if (Bop->isBitwiseOp() && Bop->getOpcode() < Opc) {
15336	S.Diag(Loc: Bop->getOperatorLoc(), DiagID: diag::warn_bitwise_op_in_bitwise_op)
15337	<< Bop->getOpcodeStr() << BinaryOperator::getOpcodeStr(Op: Opc)
15338	<< Bop->getSourceRange() << OpLoc;
15339	SuggestParentheses(Self&: S, Loc: Bop->getOperatorLoc(),
15340	Note: S.PDiag(DiagID: diag::note_precedence_silence)
15341	<< Bop->getOpcodeStr(),
15342	ParenRange: Bop->getSourceRange());
15343	}
15344	}
15345	}
15346
15347	static void DiagnoseAdditionInShift(Sema &S, SourceLocation OpLoc,
15348	Expr *SubExpr, StringRef Shift) {
15349	if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(Val: SubExpr)) {
15350	if (Bop->getOpcode() == BO_Add || Bop->getOpcode() == BO_Sub) {
15351	StringRef Op = Bop->getOpcodeStr();
15352	S.Diag(Loc: Bop->getOperatorLoc(), DiagID: diag::warn_addition_in_bitshift)
15353	<< Bop->getSourceRange() << OpLoc << Shift << Op;
15354	SuggestParentheses(Self&: S, Loc: Bop->getOperatorLoc(),
15355	Note: S.PDiag(DiagID: diag::note_precedence_silence) << Op,
15356	ParenRange: Bop->getSourceRange());
15357	}
15358	}
15359	}
15360
15361	static void DiagnoseShiftCompare(Sema &S, SourceLocation OpLoc,
15362	Expr *LHSExpr, Expr *RHSExpr) {
15363	CXXOperatorCallExpr *OCE = dyn_cast<CXXOperatorCallExpr>(Val: LHSExpr);
15364	if (!OCE)
15365	return;
15366
15367	FunctionDecl *FD = OCE->getDirectCallee();
15368	if (!FD || !FD->isOverloadedOperator())
15369	return;
15370
15371	OverloadedOperatorKind Kind = FD->getOverloadedOperator();
15372	if (Kind != OO_LessLess && Kind != OO_GreaterGreater)
15373	return;
15374
15375	S.Diag(Loc: OpLoc, DiagID: diag::warn_overloaded_shift_in_comparison)
15376	<< LHSExpr->getSourceRange() << RHSExpr->getSourceRange()
15377	<< (Kind == OO_LessLess);
15378	SuggestParentheses(Self&: S, Loc: OCE->getOperatorLoc(),
15379	Note: S.PDiag(DiagID: diag::note_precedence_silence)
15380	<< (Kind == OO_LessLess ? "<<" : ">>"),
15381	ParenRange: OCE->getSourceRange());
15382	SuggestParentheses(
15383	Self&: S, Loc: OpLoc, Note: S.PDiag(DiagID: diag::note_evaluate_comparison_first),
15384	ParenRange: SourceRange(OCE->getArg(Arg: 1)->getBeginLoc(), RHSExpr->getEndLoc()));
15385	}
15386
15387	/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky
15388	/// precedence.
15389	static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc,
15390	SourceLocation OpLoc, Expr *LHSExpr,
15391	Expr *RHSExpr){
15392	// Diagnose "arg1 'bitwise' arg2 'eq' arg3".
15393	if (BinaryOperator::isBitwiseOp(Opc))
15394	DiagnoseBitwisePrecedence(Self, Opc, OpLoc, LHSExpr, RHSExpr);
15395
15396	// Diagnose "arg1 & arg2 | arg3"
15397	if ((Opc == BO_Or || Opc == BO_Xor) &&
15398	!OpLoc.isMacroID()/* Don't warn in macros. */) {
15399	DiagnoseBitwiseOpInBitwiseOp(S&: Self, Opc, OpLoc, SubExpr: LHSExpr);
15400	DiagnoseBitwiseOpInBitwiseOp(S&: Self, Opc, OpLoc, SubExpr: RHSExpr);
15401	}
15402
15403	// Warn about arg1 || arg2 && arg3, as GCC 4.3+ does.
15404	// We don't warn for 'assert(a || b && "bad")' since this is safe.
15405	if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) {
15406	DiagnoseLogicalAndInLogicalOrLHS(S&: Self, OpLoc, LHSExpr, RHSExpr);
15407	DiagnoseLogicalAndInLogicalOrRHS(S&: Self, OpLoc, LHSExpr, RHSExpr);
15408	}
15409
15410	if ((Opc == BO_Shl && LHSExpr->getType()->isIntegralType(Ctx: Self.getASTContext()))
15411	|| Opc == BO_Shr) {
15412	StringRef Shift = BinaryOperator::getOpcodeStr(Op: Opc);
15413	DiagnoseAdditionInShift(S&: Self, OpLoc, SubExpr: LHSExpr, Shift);
15414	DiagnoseAdditionInShift(S&: Self, OpLoc, SubExpr: RHSExpr, Shift);
15415	}
15416
15417	// Warn on overloaded shift operators and comparisons, such as:
15418	// cout << 5 == 4;
15419	if (BinaryOperator::isComparisonOp(Opc))
15420	DiagnoseShiftCompare(S&: Self, OpLoc, LHSExpr, RHSExpr);
15421	}
15422
15423	ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc,
15424	tok::TokenKind Kind,
15425	Expr *LHSExpr, Expr *RHSExpr) {
15426	BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind);
15427	assert(LHSExpr && "ActOnBinOp(): missing left expression");
15428	assert(RHSExpr && "ActOnBinOp(): missing right expression");
15429
15430	// Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0"
15431	DiagnoseBinOpPrecedence(Self&: *this, Opc, OpLoc: TokLoc, LHSExpr, RHSExpr);
15432
15433	BuiltinCountedByRefKind K = BinaryOperator::isAssignmentOp(Opc)
15434	? BuiltinCountedByRefKind::Assignment
15435	: BuiltinCountedByRefKind::BinaryExpr;
15436
15437	CheckInvalidBuiltinCountedByRef(E: LHSExpr, K);
15438	CheckInvalidBuiltinCountedByRef(E: RHSExpr, K);
15439
15440	return BuildBinOp(S, OpLoc: TokLoc, Opc, LHSExpr, RHSExpr);
15441	}
15442
15443	void Sema::LookupBinOp(Scope *S, SourceLocation OpLoc, BinaryOperatorKind Opc,
15444	UnresolvedSetImpl &Functions) {
15445	OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc);
15446	if (OverOp != OO_None && OverOp != OO_Equal)
15447	LookupOverloadedOperatorName(Op: OverOp, S, Functions);
15448
15449	// In C++20 onwards, we may have a second operator to look up.
15450	if (getLangOpts().CPlusPlus20) {
15451	if (OverloadedOperatorKind ExtraOp = getRewrittenOverloadedOperator(Kind: OverOp))
15452	LookupOverloadedOperatorName(Op: ExtraOp, S, Functions);
15453	}
15454	}
15455
15456	/// Build an overloaded binary operator expression in the given scope.
15457	static ExprResult BuildOverloadedBinOp(Sema &S, Scope *Sc, SourceLocation OpLoc,
15458	BinaryOperatorKind Opc,
15459	Expr *LHS, Expr *RHS) {
15460	switch (Opc) {
15461	case BO_Assign:
15462	// In the non-overloaded case, we warn about self-assignment (x = x) for
15463	// both simple assignment and certain compound assignments where algebra
15464	// tells us the operation yields a constant result. When the operator is
15465	// overloaded, we can't do the latter because we don't want to assume that
15466	// those algebraic identities still apply; for example, a path-building
15467	// library might use operator/= to append paths. But it's still reasonable
15468	// to assume that simple assignment is just moving/copying values around
15469	// and so self-assignment is likely a bug.
15470	DiagnoseSelfAssignment(S, LHSExpr: LHS, RHSExpr: RHS, OpLoc, IsBuiltin: false);
15471	[[fallthrough]];
15472	case BO_DivAssign:
15473	case BO_RemAssign:
15474	case BO_SubAssign:
15475	case BO_AndAssign:
15476	case BO_OrAssign:
15477	case BO_XorAssign:
15478	CheckIdentityFieldAssignment(LHSExpr: LHS, RHSExpr: RHS, Loc: OpLoc, Sema&: S);
15479	break;
15480	default:
15481	break;
15482	}
15483
15484	// Find all of the overloaded operators visible from this point.
15485	UnresolvedSet<16> Functions;
15486	S.LookupBinOp(S: Sc, OpLoc, Opc, Functions);
15487
15488	// Build the (potentially-overloaded, potentially-dependent)
15489	// binary operation.
15490	return S.CreateOverloadedBinOp(OpLoc, Opc, Fns: Functions, LHS, RHS);
15491	}
15492
15493	ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc,
15494	BinaryOperatorKind Opc, Expr *LHSExpr,
15495	Expr *RHSExpr, bool ForFoldExpression) {
15496	if (!LHSExpr || !RHSExpr)
15497	return ExprError();
15498
15499	// We want to end up calling one of SemaPseudoObject::checkAssignment
15500	// (if the LHS is a pseudo-object), BuildOverloadedBinOp (if
15501	// both expressions are overloadable or either is type-dependent),
15502	// or CreateBuiltinBinOp (in any other case). We also want to get
15503	// any placeholder types out of the way.
15504
15505	// Handle pseudo-objects in the LHS.
15506	if (const BuiltinType *pty = LHSExpr->getType()->getAsPlaceholderType()) {
15507	// Assignments with a pseudo-object l-value need special analysis.
15508	if (pty->getKind() == BuiltinType::PseudoObject &&
15509	BinaryOperator::isAssignmentOp(Opc))
15510	return PseudoObject().checkAssignment(S, OpLoc, Opcode: Opc, LHS: LHSExpr, RHS: RHSExpr);
15511
15512	// Don't resolve overloads if the other type is overloadable.
15513	if (getLangOpts().CPlusPlus && pty->getKind() == BuiltinType::Overload) {
15514	// We can't actually test that if we still have a placeholder,
15515	// though. Fortunately, none of the exceptions we see in that
15516	// code below are valid when the LHS is an overload set. Note
15517	// that an overload set can be dependently-typed, but it never
15518	// instantiates to having an overloadable type.
15519	ExprResult resolvedRHS = CheckPlaceholderExpr(E: RHSExpr);
15520	if (resolvedRHS.isInvalid()) return ExprError();
15521	RHSExpr = resolvedRHS.get();
15522
15523	if (RHSExpr->isTypeDependent() ||
15524	RHSExpr->getType()->isOverloadableType())
15525	return BuildOverloadedBinOp(S&: *this, Sc: S, OpLoc, Opc, LHS: LHSExpr, RHS: RHSExpr);
15526	}
15527
15528	// If we're instantiating "a.x < b" or "A::x < b" and 'x' names a function
15529	// template, diagnose the missing 'template' keyword instead of diagnosing
15530	// an invalid use of a bound member function.
15531	//
15532	// Note that "A::x < b" might be valid if 'b' has an overloadable type due
15533	// to C++1z [over.over]/1.4, but we already checked for that case above.
15534	if (Opc == BO_LT && inTemplateInstantiation() &&
15535	(pty->getKind() == BuiltinType::BoundMember ||
15536	pty->getKind() == BuiltinType::Overload)) {
15537	auto *OE = dyn_cast<OverloadExpr>(Val: LHSExpr);
15538	if (OE && !OE->hasTemplateKeyword() && !OE->hasExplicitTemplateArgs() &&
15539	llvm::any_of(Range: OE->decls(), P: [](NamedDecl *ND) {
15540	return isa<FunctionTemplateDecl>(Val: ND);
15541	})) {
15542	Diag(Loc: OE->getQualifier() ? OE->getQualifierLoc().getBeginLoc()
15543	: OE->getNameLoc(),
15544	DiagID: diag::err_template_kw_missing)
15545	<< OE->getName().getAsIdentifierInfo();
15546	return ExprError();
15547	}
15548	}
15549
15550	ExprResult LHS = CheckPlaceholderExpr(E: LHSExpr);
15551	if (LHS.isInvalid()) return ExprError();
15552	LHSExpr = LHS.get();
15553	}
15554
15555	// Handle pseudo-objects in the RHS.
15556	if (const BuiltinType *pty = RHSExpr->getType()->getAsPlaceholderType()) {
15557	// An overload in the RHS can potentially be resolved by the type
15558	// being assigned to.
15559	if (Opc == BO_Assign && pty->getKind() == BuiltinType::Overload) {
15560	if (getLangOpts().CPlusPlus &&
15561	(LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent() ||
15562	LHSExpr->getType()->isOverloadableType()))
15563	return BuildOverloadedBinOp(S&: *this, Sc: S, OpLoc, Opc, LHS: LHSExpr, RHS: RHSExpr);
15564
15565	return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr,
15566	ForFoldExpression);
15567	}
15568
15569	// Don't resolve overloads if the other type is overloadable.
15570	if (getLangOpts().CPlusPlus && pty->getKind() == BuiltinType::Overload &&
15571	LHSExpr->getType()->isOverloadableType())
15572	return BuildOverloadedBinOp(S&: *this, Sc: S, OpLoc, Opc, LHS: LHSExpr, RHS: RHSExpr);
15573
15574	ExprResult resolvedRHS = CheckPlaceholderExpr(E: RHSExpr);
15575	if (!resolvedRHS.isUsable()) return ExprError();
15576	RHSExpr = resolvedRHS.get();
15577	}
15578
15579	if (getLangOpts().CPlusPlus) {
15580	// Otherwise, build an overloaded op if either expression is type-dependent
15581	// or has an overloadable type.
15582	if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent() ||
15583	LHSExpr->getType()->isOverloadableType() ||
15584	RHSExpr->getType()->isOverloadableType())
15585	return BuildOverloadedBinOp(S&: *this, Sc: S, OpLoc, Opc, LHS: LHSExpr, RHS: RHSExpr);
15586	}
15587
15588	if (getLangOpts().RecoveryAST &&
15589	(LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent())) {
15590	assert(!getLangOpts().CPlusPlus);
15591	assert((LHSExpr->containsErrors() || RHSExpr->containsErrors()) &&
15592	"Should only occur in error-recovery path.");
15593	if (BinaryOperator::isCompoundAssignmentOp(Opc))
15594	// C [6.15.16] p3:
15595	// An assignment expression has the value of the left operand after the
15596	// assignment, but is not an lvalue.
15597	return CompoundAssignOperator::Create(
15598	C: Context, lhs: LHSExpr, rhs: RHSExpr, opc: Opc,
15599	ResTy: LHSExpr->getType().getUnqualifiedType(), VK: VK_PRValue, OK: OK_Ordinary,
15600	opLoc: OpLoc, FPFeatures: CurFPFeatureOverrides());
15601	QualType ResultType;
15602	switch (Opc) {
15603	case BO_Assign:
15604	ResultType = LHSExpr->getType().getUnqualifiedType();
15605	break;
15606	case BO_LT:
15607	case BO_GT:
15608	case BO_LE:
15609	case BO_GE:
15610	case BO_EQ:
15611	case BO_NE:
15612	case BO_LAnd:
15613	case BO_LOr:
15614	// These operators have a fixed result type regardless of operands.
15615	ResultType = Context.IntTy;
15616	break;
15617	case BO_Comma:
15618	ResultType = RHSExpr->getType();
15619	break;
15620	default:
15621	ResultType = Context.DependentTy;
15622	break;
15623	}
15624	return BinaryOperator::Create(C: Context, lhs: LHSExpr, rhs: RHSExpr, opc: Opc, ResTy: ResultType,
15625	VK: VK_PRValue, OK: OK_Ordinary, opLoc: OpLoc,
15626	FPFeatures: CurFPFeatureOverrides());
15627	}
15628
15629	// Build a built-in binary operation.
15630	return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr, ForFoldExpression);
15631	}
15632
15633	static bool isOverflowingIntegerType(ASTContext &Ctx, QualType T) {
15634	if (T.isNull() || T->isDependentType())
15635	return false;
15636
15637	if (!Ctx.isPromotableIntegerType(T))
15638	return true;
15639
15640	return Ctx.getIntWidth(T) >= Ctx.getIntWidth(T: Ctx.IntTy);
15641	}
15642
15643	ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc,
15644	UnaryOperatorKind Opc, Expr *InputExpr,
15645	bool IsAfterAmp) {
15646	ExprResult Input = InputExpr;
15647	ExprValueKind VK = VK_PRValue;
15648	ExprObjectKind OK = OK_Ordinary;
15649	QualType resultType;
15650	bool CanOverflow = false;
15651
15652	bool ConvertHalfVec = false;
15653	if (getLangOpts().OpenCL) {
15654	QualType Ty = InputExpr->getType();
15655	// The only legal unary operation for atomics is '&'.
15656	if ((Opc != UO_AddrOf && Ty->isAtomicType()) ||
15657	// OpenCL special types - image, sampler, pipe, and blocks are to be used
15658	// only with a builtin functions and therefore should be disallowed here.
15659	(Ty->isImageType() || Ty->isSamplerT() || Ty->isPipeType()
15660	|| Ty->isBlockPointerType())) {
15661	return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_typecheck_unary_expr)
15662	<< InputExpr->getType()
15663	<< Input.get()->getSourceRange());
15664	}
15665	}
15666
15667	if (getLangOpts().HLSL && OpLoc.isValid()) {
15668	if (Opc == UO_AddrOf)
15669	return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_hlsl_operator_unsupported) << 0);
15670	if (Opc == UO_Deref)
15671	return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_hlsl_operator_unsupported) << 1);
15672	}
15673
15674	if (InputExpr->isTypeDependent() &&
15675	InputExpr->getType()->isSpecificBuiltinType(K: BuiltinType::Dependent)) {
15676	resultType = Context.DependentTy;
15677	} else {
15678	switch (Opc) {
15679	case UO_PreInc:
15680	case UO_PreDec:
15681	case UO_PostInc:
15682	case UO_PostDec:
15683	resultType =
15684	CheckIncrementDecrementOperand(S&: *this, Op: Input.get(), VK, OK, OpLoc,
15685	IsInc: Opc == UO_PreInc || Opc == UO_PostInc,
15686	IsPrefix: Opc == UO_PreInc || Opc == UO_PreDec);
15687	CanOverflow = isOverflowingIntegerType(Ctx&: Context, T: resultType);
15688	break;
15689	case UO_AddrOf:
15690	resultType = CheckAddressOfOperand(OrigOp&: Input, OpLoc);
15691	CheckAddressOfNoDeref(E: InputExpr);
15692	RecordModifiableNonNullParam(S&: *this, Exp: InputExpr);
15693	break;
15694	case UO_Deref: {
15695	Input = DefaultFunctionArrayLvalueConversion(E: Input.get());
15696	if (Input.isInvalid())
15697	return ExprError();
15698	resultType =
15699	CheckIndirectionOperand(S&: *this, Op: Input.get(), VK, OpLoc, IsAfterAmp);
15700	break;
15701	}
15702	case UO_Plus:
15703	case UO_Minus:
15704	CanOverflow = Opc == UO_Minus &&
15705	isOverflowingIntegerType(Ctx&: Context, T: Input.get()->getType());
15706	Input = UsualUnaryConversions(E: Input.get());
15707	if (Input.isInvalid())
15708	return ExprError();
15709	// Unary plus and minus require promoting an operand of half vector to a
15710	// float vector and truncating the result back to a half vector. For now,
15711	// we do this only when HalfArgsAndReturns is set (that is, when the
15712	// target is arm or arm64).
15713	ConvertHalfVec = needsConversionOfHalfVec(OpRequiresConversion: true, Ctx&: Context, E0: Input.get());
15714
15715	// If the operand is a half vector, promote it to a float vector.
15716	if (ConvertHalfVec)
15717	Input = convertVector(E: Input.get(), ElementType: Context.FloatTy, S&: *this);
15718	resultType = Input.get()->getType();
15719	if (resultType->isArithmeticType()) // C99 6.5.3.3p1
15720	break;
15721	else if (resultType->isVectorType() &&
15722	// The z vector extensions don't allow + or - with bool vectors.
15723	(!Context.getLangOpts().ZVector ||
15724	resultType->castAs<VectorType>()->getVectorKind() !=
15725	VectorKind::AltiVecBool))
15726	break;
15727	else if (resultType->isSveVLSBuiltinType()) // SVE vectors allow + and -
15728	break;
15729	else if (getLangOpts().CPlusPlus && // C++ [expr.unary.op]p6
15730	Opc == UO_Plus && resultType->isPointerType())
15731	break;
15732
15733	return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_typecheck_unary_expr)
15734	<< resultType << Input.get()->getSourceRange());
15735
15736	case UO_Not: // bitwise complement
15737	Input = UsualUnaryConversions(E: Input.get());
15738	if (Input.isInvalid())
15739	return ExprError();
15740	resultType = Input.get()->getType();
15741	// C99 6.5.3.3p1. We allow complex int and float as a GCC extension.
15742	if (resultType->isComplexType() || resultType->isComplexIntegerType())
15743	// C99 does not support '~' for complex conjugation.
15744	Diag(Loc: OpLoc, DiagID: diag::ext_integer_complement_complex)
15745	<< resultType << Input.get()->getSourceRange();
15746	else if (resultType->hasIntegerRepresentation())
15747	break;
15748	else if (resultType->isExtVectorType() && Context.getLangOpts().OpenCL) {
15749	// OpenCL v1.1 s6.3.f: The bitwise operator not (~) does not operate
15750	// on vector float types.
15751	QualType T = resultType->castAs<ExtVectorType>()->getElementType();
15752	if (!T->isIntegerType())
15753	return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_typecheck_unary_expr)
15754	<< resultType << Input.get()->getSourceRange());
15755	} else {
15756	return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_typecheck_unary_expr)
15757	<< resultType << Input.get()->getSourceRange());
15758	}
15759	break;
15760
15761	case UO_LNot: // logical negation
15762	// Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5).
15763	Input = DefaultFunctionArrayLvalueConversion(E: Input.get());
15764	if (Input.isInvalid())
15765	return ExprError();
15766	resultType = Input.get()->getType();
15767
15768	// Though we still have to promote half FP to float...
15769	if (resultType->isHalfType() && !Context.getLangOpts().NativeHalfType) {
15770	Input = ImpCastExprToType(E: Input.get(), Type: Context.FloatTy, CK: CK_FloatingCast)
15771	.get();
15772	resultType = Context.FloatTy;
15773	}
15774
15775	// WebAsembly tables can't be used in unary expressions.
15776	if (resultType->isPointerType() &&
15777	resultType->getPointeeType().isWebAssemblyReferenceType()) {
15778	return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_typecheck_unary_expr)
15779	<< resultType << Input.get()->getSourceRange());
15780	}
15781
15782	if (resultType->isScalarType() && !isScopedEnumerationType(T: resultType)) {
15783	// C99 6.5.3.3p1: ok, fallthrough;
15784	if (Context.getLangOpts().CPlusPlus) {
15785	// C++03 [expr.unary.op]p8, C++0x [expr.unary.op]p9:
15786	// operand contextually converted to bool.
15787	Input = ImpCastExprToType(E: Input.get(), Type: Context.BoolTy,
15788	CK: ScalarTypeToBooleanCastKind(ScalarTy: resultType));
15789	} else if (Context.getLangOpts().OpenCL &&
15790	Context.getLangOpts().OpenCLVersion < 120) {
15791	// OpenCL v1.1 6.3.h: The logical operator not (!) does not
15792	// operate on scalar float types.
15793	if (!resultType->isIntegerType() && !resultType->isPointerType())
15794	return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_typecheck_unary_expr)
15795	<< resultType << Input.get()->getSourceRange());
15796	}
15797	} else if (resultType->isExtVectorType()) {
15798	if (Context.getLangOpts().OpenCL &&
15799	Context.getLangOpts().getOpenCLCompatibleVersion() < 120) {
15800	// OpenCL v1.1 6.3.h: The logical operator not (!) does not
15801	// operate on vector float types.
15802	QualType T = resultType->castAs<ExtVectorType>()->getElementType();
15803	if (!T->isIntegerType())
15804	return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_typecheck_unary_expr)
15805	<< resultType << Input.get()->getSourceRange());
15806	}
15807	// Vector logical not returns the signed variant of the operand type.
15808	resultType = GetSignedVectorType(V: resultType);
15809	break;
15810	} else if (Context.getLangOpts().CPlusPlus &&
15811	resultType->isVectorType()) {
15812	const VectorType *VTy = resultType->castAs<VectorType>();
15813	if (VTy->getVectorKind() != VectorKind::Generic)
15814	return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_typecheck_unary_expr)
15815	<< resultType << Input.get()->getSourceRange());
15816
15817	// Vector logical not returns the signed variant of the operand type.
15818	resultType = GetSignedVectorType(V: resultType);
15819	break;
15820	} else {
15821	return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_typecheck_unary_expr)
15822	<< resultType << Input.get()->getSourceRange());
15823	}
15824
15825	// LNot always has type int. C99 6.5.3.3p5.
15826	// In C++, it's bool. C++ 5.3.1p8
15827	resultType = Context.getLogicalOperationType();
15828	break;
15829	case UO_Real:
15830	case UO_Imag:
15831	resultType = CheckRealImagOperand(S&: *this, V&: Input, Loc: OpLoc, IsReal: Opc == UO_Real);
15832	// _Real maps ordinary l-values into ordinary l-values. _Imag maps
15833	// ordinary complex l-values to ordinary l-values and all other values to
15834	// r-values.
15835	if (Input.isInvalid())
15836	return ExprError();
15837	if (Opc == UO_Real || Input.get()->getType()->isAnyComplexType()) {
15838	if (Input.get()->isGLValue() &&
15839	Input.get()->getObjectKind() == OK_Ordinary)
15840	VK = Input.get()->getValueKind();
15841	} else if (!getLangOpts().CPlusPlus) {
15842	// In C, a volatile scalar is read by __imag. In C++, it is not.
15843	Input = DefaultLvalueConversion(E: Input.get());
15844	}
15845	break;
15846	case UO_Extension:
15847	resultType = Input.get()->getType();
15848	VK = Input.get()->getValueKind();
15849	OK = Input.get()->getObjectKind();
15850	break;
15851	case UO_Coawait:
15852	// It's unnecessary to represent the pass-through operator co_await in the
15853	// AST; just return the input expression instead.
15854	assert(!Input.get()->getType()->isDependentType() &&
15855	"the co_await expression must be non-dependant before "
15856	"building operator co_await");
15857	return Input;
15858	}
15859	}
15860	if (resultType.isNull() || Input.isInvalid())
15861	return ExprError();
15862
15863	// Check for array bounds violations in the operand of the UnaryOperator,
15864	// except for the '*' and '&' operators that have to be handled specially
15865	// by CheckArrayAccess (as there are special cases like &array[arraysize]
15866	// that are explicitly defined as valid by the standard).
15867	if (Opc != UO_AddrOf && Opc != UO_Deref)
15868	CheckArrayAccess(E: Input.get());
15869
15870	auto *UO =
15871	UnaryOperator::Create(C: Context, input: Input.get(), opc: Opc, type: resultType, VK, OK,
15872	l: OpLoc, CanOverflow, FPFeatures: CurFPFeatureOverrides());
15873
15874	if (Opc == UO_Deref && UO->getType()->hasAttr(AK: attr::NoDeref) &&
15875	!isa<ArrayType>(Val: UO->getType().getDesugaredType(Context)) &&
15876	!isUnevaluatedContext())
15877	ExprEvalContexts.back().PossibleDerefs.insert(Ptr: UO);
15878
15879	// Convert the result back to a half vector.
15880	if (ConvertHalfVec)
15881	return convertVector(E: UO, ElementType: Context.HalfTy, S&: *this);
15882	return UO;
15883	}
15884
15885	bool Sema::isQualifiedMemberAccess(Expr *E) {
15886	if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: E)) {
15887	if (!DRE->getQualifier())
15888	return false;
15889
15890	ValueDecl *VD = DRE->getDecl();
15891	if (!VD->isCXXClassMember())
15892	return false;
15893
15894	if (isa<FieldDecl>(Val: VD) || isa<IndirectFieldDecl>(Val: VD))
15895	return true;
15896	if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Val: VD))
15897	return Method->isImplicitObjectMemberFunction();
15898
15899	return false;
15900	}
15901
15902	if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Val: E)) {
15903	if (!ULE->getQualifier())
15904	return false;
15905
15906	for (NamedDecl *D : ULE->decls()) {
15907	if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Val: D)) {
15908	if (Method->isImplicitObjectMemberFunction())
15909	return true;
15910	} else {
15911	// Overload set does not contain methods.
15912	break;
15913	}
15914	}
15915
15916	return false;
15917	}
15918
15919	return false;
15920	}
15921
15922	ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc,
15923	UnaryOperatorKind Opc, Expr *Input,
15924	bool IsAfterAmp) {
15925	// First things first: handle placeholders so that the
15926	// overloaded-operator check considers the right type.
15927	if (const BuiltinType *pty = Input->getType()->getAsPlaceholderType()) {
15928	// Increment and decrement of pseudo-object references.
15929	if (pty->getKind() == BuiltinType::PseudoObject &&
15930	UnaryOperator::isIncrementDecrementOp(Op: Opc))
15931	return PseudoObject().checkIncDec(S, OpLoc, Opcode: Opc, Op: Input);
15932
15933	// extension is always a builtin operator.
15934	if (Opc == UO_Extension)
15935	return CreateBuiltinUnaryOp(OpLoc, Opc, InputExpr: Input);
15936
15937	// & gets special logic for several kinds of placeholder.
15938	// The builtin code knows what to do.
15939	if (Opc == UO_AddrOf &&
15940	(pty->getKind() == BuiltinType::Overload ||
15941	pty->getKind() == BuiltinType::UnknownAny ||
15942	pty->getKind() == BuiltinType::BoundMember))
15943	return CreateBuiltinUnaryOp(OpLoc, Opc, InputExpr: Input);
15944
15945	// Anything else needs to be handled now.
15946	ExprResult Result = CheckPlaceholderExpr(E: Input);
15947	if (Result.isInvalid()) return ExprError();
15948	Input = Result.get();
15949	}
15950
15951	if (getLangOpts().CPlusPlus && Input->getType()->isOverloadableType() &&
15952	UnaryOperator::getOverloadedOperator(Opc) != OO_None &&
15953	!(Opc == UO_AddrOf && isQualifiedMemberAccess(E: Input))) {
15954	// Find all of the overloaded operators visible from this point.
15955	UnresolvedSet<16> Functions;
15956	OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc);
15957	if (S && OverOp != OO_None)
15958	LookupOverloadedOperatorName(Op: OverOp, S, Functions);
15959
15960	return CreateOverloadedUnaryOp(OpLoc, Opc, Fns: Functions, input: Input);
15961	}
15962
15963	return CreateBuiltinUnaryOp(OpLoc, Opc, InputExpr: Input, IsAfterAmp);
15964	}
15965
15966	ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, tok::TokenKind Op,
15967	Expr *Input, bool IsAfterAmp) {
15968	return BuildUnaryOp(S, OpLoc, Opc: ConvertTokenKindToUnaryOpcode(Kind: Op), Input,
15969	IsAfterAmp);
15970	}
15971
15972	ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc,
15973	LabelDecl *TheDecl) {
15974	TheDecl->markUsed(C&: Context);
15975	// Create the AST node. The address of a label always has type 'void*'.
15976	auto *Res = new (Context) AddrLabelExpr(
15977	OpLoc, LabLoc, TheDecl, Context.getPointerType(T: Context.VoidTy));
15978
15979	if (getCurFunction())
15980	getCurFunction()->AddrLabels.push_back(Elt: Res);
15981
15982	return Res;
15983	}
15984
15985	void Sema::ActOnStartStmtExpr() {
15986	PushExpressionEvaluationContext(NewContext: ExprEvalContexts.back().Context);
15987	// Make sure we diagnose jumping into a statement expression.
15988	setFunctionHasBranchProtectedScope();
15989	}
15990
15991	void Sema::ActOnStmtExprError() {
15992	// Note that function is also called by TreeTransform when leaving a
15993	// StmtExpr scope without rebuilding anything.
15994
15995	DiscardCleanupsInEvaluationContext();
15996	PopExpressionEvaluationContext();
15997	}
15998
15999	ExprResult Sema::ActOnStmtExpr(Scope *S, SourceLocation LPLoc, Stmt *SubStmt,
16000	SourceLocation RPLoc) {
16001	return BuildStmtExpr(LPLoc, SubStmt, RPLoc, TemplateDepth: getTemplateDepth(S));
16002	}
16003
16004	ExprResult Sema::BuildStmtExpr(SourceLocation LPLoc, Stmt *SubStmt,
16005	SourceLocation RPLoc, unsigned TemplateDepth) {
16006	assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!");
16007	CompoundStmt *Compound = cast<CompoundStmt>(Val: SubStmt);
16008
16009	if (hasAnyUnrecoverableErrorsInThisFunction())
16010	DiscardCleanupsInEvaluationContext();
16011	assert(!Cleanup.exprNeedsCleanups() &&
16012	"cleanups within StmtExpr not correctly bound!");
16013	PopExpressionEvaluationContext();
16014
16015	// FIXME: there are a variety of strange constraints to enforce here, for
16016	// example, it is not possible to goto into a stmt expression apparently.
16017	// More semantic analysis is needed.
16018
16019	// If there are sub-stmts in the compound stmt, take the type of the last one
16020	// as the type of the stmtexpr.
16021	QualType Ty = Context.VoidTy;
16022	bool StmtExprMayBindToTemp = false;
16023	if (!Compound->body_empty()) {
16024	// For GCC compatibility we get the last Stmt excluding trailing NullStmts.
16025	if (const auto *LastStmt =
16026	dyn_cast<ValueStmt>(Val: Compound->getStmtExprResult())) {
16027	if (const Expr *Value = LastStmt->getExprStmt()) {
16028	StmtExprMayBindToTemp = true;
16029	Ty = Value->getType();
16030	}
16031	}
16032	}
16033
16034	// FIXME: Check that expression type is complete/non-abstract; statement
16035	// expressions are not lvalues.
16036	Expr *ResStmtExpr =
16037	new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc, TemplateDepth);
16038	if (StmtExprMayBindToTemp)
16039	return MaybeBindToTemporary(E: ResStmtExpr);
16040	return ResStmtExpr;
16041	}
16042
16043	ExprResult Sema::ActOnStmtExprResult(ExprResult ER) {
16044	if (ER.isInvalid())
16045	return ExprError();
16046
16047	// Do function/array conversion on the last expression, but not
16048	// lvalue-to-rvalue. However, initialize an unqualified type.
16049	ER = DefaultFunctionArrayConversion(E: ER.get());
16050	if (ER.isInvalid())
16051	return ExprError();
16052	Expr *E = ER.get();
16053
16054	if (E->isTypeDependent())
16055	return E;
16056
16057	// In ARC, if the final expression ends in a consume, splice
16058	// the consume out and bind it later. In the alternate case
16059	// (when dealing with a retainable type), the result
16060	// initialization will create a produce. In both cases the
16061	// result will be +1, and we'll need to balance that out with
16062	// a bind.
16063	auto *Cast = dyn_cast<ImplicitCastExpr>(Val: E);
16064	if (Cast && Cast->getCastKind() == CK_ARCConsumeObject)
16065	return Cast->getSubExpr();
16066
16067	// FIXME: Provide a better location for the initialization.
16068	return PerformCopyInitialization(
16069	Entity: InitializedEntity::InitializeStmtExprResult(
16070	ReturnLoc: E->getBeginLoc(), Type: E->getType().getAtomicUnqualifiedType()),
16071	EqualLoc: SourceLocation(), Init: E);
16072	}
16073
16074	ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc,
16075	TypeSourceInfo *TInfo,
16076	ArrayRef<OffsetOfComponent> Components,
16077	SourceLocation RParenLoc) {
16078	QualType ArgTy = TInfo->getType();
16079	bool Dependent = ArgTy->isDependentType();
16080	SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange();
16081
16082	// We must have at least one component that refers to the type, and the first
16083	// one is known to be a field designator. Verify that the ArgTy represents
16084	// a struct/union/class.
16085	if (!Dependent && !ArgTy->isRecordType())
16086	return ExprError(Diag(Loc: BuiltinLoc, DiagID: diag::err_offsetof_record_type)
16087	<< ArgTy << TypeRange);
16088
16089	// Type must be complete per C99 7.17p3 because a declaring a variable
16090	// with an incomplete type would be ill-formed.
16091	if (!Dependent
16092	&& RequireCompleteType(Loc: BuiltinLoc, T: ArgTy,
16093	DiagID: diag::err_offsetof_incomplete_type, Args: TypeRange))
16094	return ExprError();
16095
16096	bool DidWarnAboutNonPOD = false;
16097	QualType CurrentType = ArgTy;
16098	SmallVector<OffsetOfNode, 4> Comps;
16099	SmallVector<Expr*, 4> Exprs;
16100	for (const OffsetOfComponent &OC : Components) {
16101	if (OC.isBrackets) {
16102	// Offset of an array sub-field. TODO: Should we allow vector elements?
16103	if (!CurrentType->isDependentType()) {
16104	const ArrayType *AT = Context.getAsArrayType(T: CurrentType);
16105	if(!AT)
16106	return ExprError(Diag(Loc: OC.LocEnd, DiagID: diag::err_offsetof_array_type)
16107	<< CurrentType);
16108	CurrentType = AT->getElementType();
16109	} else
16110	CurrentType = Context.DependentTy;
16111
16112	ExprResult IdxRval = DefaultLvalueConversion(E: static_cast<Expr*>(OC.U.E));
16113	if (IdxRval.isInvalid())
16114	return ExprError();
16115	Expr *Idx = IdxRval.get();
16116
16117	// The expression must be an integral expression.
16118	// FIXME: An integral constant expression?
16119	if (!Idx->isTypeDependent() && !Idx->isValueDependent() &&
16120	!Idx->getType()->isIntegerType())
16121	return ExprError(
16122	Diag(Loc: Idx->getBeginLoc(), DiagID: diag::err_typecheck_subscript_not_integer)
16123	<< Idx->getSourceRange());
16124
16125	// Record this array index.
16126	Comps.push_back(Elt: OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd));
16127	Exprs.push_back(Elt: Idx);
16128	continue;
16129	}
16130
16131	// Offset of a field.
16132	if (CurrentType->isDependentType()) {
16133	// We have the offset of a field, but we can't look into the dependent
16134	// type. Just record the identifier of the field.
16135	Comps.push_back(Elt: OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd));
16136	CurrentType = Context.DependentTy;
16137	continue;
16138	}
16139
16140	// We need to have a complete type to look into.
16141	if (RequireCompleteType(Loc: OC.LocStart, T: CurrentType,
16142	DiagID: diag::err_offsetof_incomplete_type))
16143	return ExprError();
16144
16145	// Look for the designated field.
16146	const RecordType *RC = CurrentType->getAs<RecordType>();
16147	if (!RC)
16148	return ExprError(Diag(Loc: OC.LocEnd, DiagID: diag::err_offsetof_record_type)
16149	<< CurrentType);
16150	RecordDecl *RD = RC->getDecl();
16151
16152	// C++ [lib.support.types]p5:
16153	// The macro offsetof accepts a restricted set of type arguments in this
16154	// International Standard. type shall be a POD structure or a POD union
16155	// (clause 9).
16156	// C++11 [support.types]p4:
16157	// If type is not a standard-layout class (Clause 9), the results are
16158	// undefined.
16159	if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(Val: RD)) {
16160	bool IsSafe = LangOpts.CPlusPlus11? CRD->isStandardLayout() : CRD->isPOD();
16161	unsigned DiagID =
16162	LangOpts.CPlusPlus11? diag::ext_offsetof_non_standardlayout_type
16163	: diag::ext_offsetof_non_pod_type;
16164
16165	if (!IsSafe && !DidWarnAboutNonPOD && !isUnevaluatedContext()) {
16166	Diag(Loc: BuiltinLoc, DiagID)
16167	<< SourceRange(Components[0].LocStart, OC.LocEnd) << CurrentType;
16168	DidWarnAboutNonPOD = true;
16169	}
16170	}
16171
16172	// Look for the field.
16173	LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName);
16174	LookupQualifiedName(R, LookupCtx: RD);
16175	FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>();
16176	IndirectFieldDecl *IndirectMemberDecl = nullptr;
16177	if (!MemberDecl) {
16178	if ((IndirectMemberDecl = R.getAsSingle<IndirectFieldDecl>()))
16179	MemberDecl = IndirectMemberDecl->getAnonField();
16180	}
16181
16182	if (!MemberDecl) {
16183	// Lookup could be ambiguous when looking up a placeholder variable
16184	// __builtin_offsetof(S, _).
16185	// In that case we would already have emitted a diagnostic
16186	if (!R.isAmbiguous())
16187	Diag(Loc: BuiltinLoc, DiagID: diag::err_no_member)
16188	<< OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd);
16189	return ExprError();
16190	}
16191
16192	// C99 7.17p3:
16193	// (If the specified member is a bit-field, the behavior is undefined.)
16194	//
16195	// We diagnose this as an error.
16196	if (MemberDecl->isBitField()) {
16197	Diag(Loc: OC.LocEnd, DiagID: diag::err_offsetof_bitfield)
16198	<< MemberDecl->getDeclName()
16199	<< SourceRange(BuiltinLoc, RParenLoc);
16200	Diag(Loc: MemberDecl->getLocation(), DiagID: diag::note_bitfield_decl);
16201	return ExprError();
16202	}
16203
16204	RecordDecl *Parent = MemberDecl->getParent();
16205	if (IndirectMemberDecl)
16206	Parent = cast<RecordDecl>(Val: IndirectMemberDecl->getDeclContext());
16207
16208	// If the member was found in a base class, introduce OffsetOfNodes for
16209	// the base class indirections.
16210	CXXBasePaths Paths;
16211	if (IsDerivedFrom(Loc: OC.LocStart, Derived: CurrentType, Base: Context.getTypeDeclType(Decl: Parent),
16212	Paths)) {
16213	if (Paths.getDetectedVirtual()) {
16214	Diag(Loc: OC.LocEnd, DiagID: diag::err_offsetof_field_of_virtual_base)
16215	<< MemberDecl->getDeclName()
16216	<< SourceRange(BuiltinLoc, RParenLoc);
16217	return ExprError();
16218	}
16219
16220	CXXBasePath &Path = Paths.front();
16221	for (const CXXBasePathElement &B : Path)
16222	Comps.push_back(Elt: OffsetOfNode(B.Base));
16223	}
16224
16225	if (IndirectMemberDecl) {
16226	for (auto *FI : IndirectMemberDecl->chain()) {
16227	assert(isa<FieldDecl>(FI));
16228	Comps.push_back(Elt: OffsetOfNode(OC.LocStart,
16229	cast<FieldDecl>(Val: FI), OC.LocEnd));
16230	}
16231	} else
16232	Comps.push_back(Elt: OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd));
16233
16234	CurrentType = MemberDecl->getType().getNonReferenceType();
16235	}
16236
16237	return OffsetOfExpr::Create(C: Context, type: Context.getSizeType(), OperatorLoc: BuiltinLoc, tsi: TInfo,
16238	comps: Comps, exprs: Exprs, RParenLoc);
16239	}
16240
16241	ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
16242	SourceLocation BuiltinLoc,
16243	SourceLocation TypeLoc,
16244	ParsedType ParsedArgTy,
16245	ArrayRef<OffsetOfComponent> Components,
16246	SourceLocation RParenLoc) {
16247
16248	TypeSourceInfo *ArgTInfo;
16249	QualType ArgTy = GetTypeFromParser(Ty: ParsedArgTy, TInfo: &ArgTInfo);
16250	if (ArgTy.isNull())
16251	return ExprError();
16252
16253	if (!ArgTInfo)
16254	ArgTInfo = Context.getTrivialTypeSourceInfo(T: ArgTy, Loc: TypeLoc);
16255
16256	return BuildBuiltinOffsetOf(BuiltinLoc, TInfo: ArgTInfo, Components, RParenLoc);
16257	}
16258
16259
16260	ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc,
16261	Expr *CondExpr,
16262	Expr *LHSExpr, Expr *RHSExpr,
16263	SourceLocation RPLoc) {
16264	assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)");
16265
16266	ExprValueKind VK = VK_PRValue;
16267	ExprObjectKind OK = OK_Ordinary;
16268	QualType resType;
16269	bool CondIsTrue = false;
16270	if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) {
16271	resType = Context.DependentTy;
16272	} else {
16273	// The conditional expression is required to be a constant expression.
16274	llvm::APSInt condEval(32);
16275	ExprResult CondICE = VerifyIntegerConstantExpression(
16276	E: CondExpr, Result: &condEval, DiagID: diag::err_typecheck_choose_expr_requires_constant);
16277	if (CondICE.isInvalid())
16278	return ExprError();
16279	CondExpr = CondICE.get();
16280	CondIsTrue = condEval.getZExtValue();
16281
16282	// If the condition is > zero, then the AST type is the same as the LHSExpr.
16283	Expr *ActiveExpr = CondIsTrue ? LHSExpr : RHSExpr;
16284
16285	resType = ActiveExpr->getType();
16286	VK = ActiveExpr->getValueKind();
16287	OK = ActiveExpr->getObjectKind();
16288	}
16289
16290	return new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr,
16291	resType, VK, OK, RPLoc, CondIsTrue);
16292	}
16293
16294	//===----------------------------------------------------------------------===//
16295	// Clang Extensions.
16296	//===----------------------------------------------------------------------===//
16297
16298	void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope) {
16299	BlockDecl *Block = BlockDecl::Create(C&: Context, DC: CurContext, L: CaretLoc);
16300
16301	if (LangOpts.CPlusPlus) {
16302	MangleNumberingContext *MCtx;
16303	Decl *ManglingContextDecl;
16304	std::tie(args&: MCtx, args&: ManglingContextDecl) =
16305	getCurrentMangleNumberContext(DC: Block->getDeclContext());
16306	if (MCtx) {
16307	unsigned ManglingNumber = MCtx->getManglingNumber(BD: Block);
16308	Block->setBlockMangling(Number: ManglingNumber, Ctx: ManglingContextDecl);
16309	}
16310	}
16311
16312	PushBlockScope(BlockScope: CurScope, Block);
16313	CurContext->addDecl(D: Block);
16314	if (CurScope)
16315	PushDeclContext(S: CurScope, DC: Block);
16316	else
16317	CurContext = Block;
16318
16319	getCurBlock()->HasImplicitReturnType = true;
16320
16321	// Enter a new evaluation context to insulate the block from any
16322	// cleanups from the enclosing full-expression.
16323	PushExpressionEvaluationContext(
16324	NewContext: ExpressionEvaluationContext::PotentiallyEvaluated);
16325	}
16326
16327	void Sema::ActOnBlockArguments(SourceLocation CaretLoc, Declarator &ParamInfo,
16328	Scope *CurScope) {
16329	assert(ParamInfo.getIdentifier() == nullptr &&
16330	"block-id should have no identifier!");
16331	assert(ParamInfo.getContext() == DeclaratorContext::BlockLiteral);
16332	BlockScopeInfo *CurBlock = getCurBlock();
16333
16334	TypeSourceInfo *Sig = GetTypeForDeclarator(D&: ParamInfo);
16335	QualType T = Sig->getType();
16336	DiagnoseUnexpandedParameterPack(Loc: CaretLoc, T: Sig, UPPC: UPPC_Block);
16337
16338	// GetTypeForDeclarator always produces a function type for a block
16339	// literal signature. Furthermore, it is always a FunctionProtoType
16340	// unless the function was written with a typedef.
16341	assert(T->isFunctionType() &&
16342	"GetTypeForDeclarator made a non-function block signature");
16343
16344	// Look for an explicit signature in that function type.
16345	FunctionProtoTypeLoc ExplicitSignature;
16346
16347	if ((ExplicitSignature = Sig->getTypeLoc()
16348	.getAsAdjusted<FunctionProtoTypeLoc>())) {
16349
16350	// Check whether that explicit signature was synthesized by
16351	// GetTypeForDeclarator. If so, don't save that as part of the
16352	// written signature.
16353	if (ExplicitSignature.getLocalRangeBegin() ==
16354	ExplicitSignature.getLocalRangeEnd()) {
16355	// This would be much cheaper if we stored TypeLocs instead of
16356	// TypeSourceInfos.
16357	TypeLoc Result = ExplicitSignature.getReturnLoc();
16358	unsigned Size = Result.getFullDataSize();
16359	Sig = Context.CreateTypeSourceInfo(T: Result.getType(), Size);
16360	Sig->getTypeLoc().initializeFullCopy(Other: Result, Size);
16361
16362	ExplicitSignature = FunctionProtoTypeLoc();
16363	}
16364	}
16365
16366	CurBlock->TheDecl->setSignatureAsWritten(Sig);
16367	CurBlock->FunctionType = T;
16368
16369	const auto *Fn = T->castAs<FunctionType>();
16370	QualType RetTy = Fn->getReturnType();
16371	bool isVariadic =
16372	(isa<FunctionProtoType>(Val: Fn) && cast<FunctionProtoType>(Val: Fn)->isVariadic());
16373
16374	CurBlock->TheDecl->setIsVariadic(isVariadic);
16375
16376	// Context.DependentTy is used as a placeholder for a missing block
16377	// return type. TODO: what should we do with declarators like:
16378	// ^ * { ... }
16379	// If the answer is "apply template argument deduction"....
16380	if (RetTy != Context.DependentTy) {
16381	CurBlock->ReturnType = RetTy;
16382	CurBlock->TheDecl->setBlockMissingReturnType(false);
16383	CurBlock->HasImplicitReturnType = false;
16384	}
16385
16386	// Push block parameters from the declarator if we had them.
16387	SmallVector<ParmVarDecl*, 8> Params;
16388	if (ExplicitSignature) {
16389	for (unsigned I = 0, E = ExplicitSignature.getNumParams(); I != E; ++I) {
16390	ParmVarDecl *Param = ExplicitSignature.getParam(i: I);
16391	if (Param->getIdentifier() == nullptr && !Param->isImplicit() &&
16392	!Param->isInvalidDecl() && !getLangOpts().CPlusPlus) {
16393	// Diagnose this as an extension in C17 and earlier.
16394	if (!getLangOpts().C23)
16395	Diag(Loc: Param->getLocation(), DiagID: diag::ext_parameter_name_omitted_c23);
16396	}
16397	Params.push_back(Elt: Param);
16398	}
16399
16400	// Fake up parameter variables if we have a typedef, like
16401	// ^ fntype { ... }
16402	} else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) {
16403	for (const auto &I : Fn->param_types()) {
16404	ParmVarDecl *Param = BuildParmVarDeclForTypedef(
16405	DC: CurBlock->TheDecl, Loc: ParamInfo.getBeginLoc(), T: I);
16406	Params.push_back(Elt: Param);
16407	}
16408	}
16409
16410	// Set the parameters on the block decl.
16411	if (!Params.empty()) {
16412	CurBlock->TheDecl->setParams(Params);
16413	CheckParmsForFunctionDef(Parameters: CurBlock->TheDecl->parameters(),
16414	/*CheckParameterNames=*/false);
16415	}
16416
16417	// Finally we can process decl attributes.
16418	ProcessDeclAttributes(S: CurScope, D: CurBlock->TheDecl, PD: ParamInfo);
16419
16420	// Put the parameter variables in scope.
16421	for (auto *AI : CurBlock->TheDecl->parameters()) {
16422	AI->setOwningFunction(CurBlock->TheDecl);
16423
16424	// If this has an identifier, add it to the scope stack.
16425	if (AI->getIdentifier()) {
16426	CheckShadow(S: CurBlock->TheScope, D: AI);
16427
16428	PushOnScopeChains(D: AI, S: CurBlock->TheScope);
16429	}
16430
16431	if (AI->isInvalidDecl())
16432	CurBlock->TheDecl->setInvalidDecl();
16433	}
16434	}
16435
16436	void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) {
16437	// Leave the expression-evaluation context.
16438	DiscardCleanupsInEvaluationContext();
16439	PopExpressionEvaluationContext();
16440
16441	// Pop off CurBlock, handle nested blocks.
16442	PopDeclContext();
16443	PopFunctionScopeInfo();
16444	}
16445
16446	ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc,
16447	Stmt *Body, Scope *CurScope) {
16448	// If blocks are disabled, emit an error.
16449	if (!LangOpts.Blocks)
16450	Diag(Loc: CaretLoc, DiagID: diag::err_blocks_disable) << LangOpts.OpenCL;
16451
16452	// Leave the expression-evaluation context.
16453	if (hasAnyUnrecoverableErrorsInThisFunction())
16454	DiscardCleanupsInEvaluationContext();
16455	assert(!Cleanup.exprNeedsCleanups() &&
16456	"cleanups within block not correctly bound!");
16457	PopExpressionEvaluationContext();
16458
16459	BlockScopeInfo *BSI = cast<BlockScopeInfo>(Val: FunctionScopes.back());
16460	BlockDecl *BD = BSI->TheDecl;
16461
16462	maybeAddDeclWithEffects(D: BD);
16463
16464	if (BSI->HasImplicitReturnType)
16465	deduceClosureReturnType(CSI&: *BSI);
16466
16467	QualType RetTy = Context.VoidTy;
16468	if (!BSI->ReturnType.isNull())
16469	RetTy = BSI->ReturnType;
16470
16471	bool NoReturn = BD->hasAttr<NoReturnAttr>();
16472	QualType BlockTy;
16473
16474	// If the user wrote a function type in some form, try to use that.
16475	if (!BSI->FunctionType.isNull()) {
16476	const FunctionType *FTy = BSI->FunctionType->castAs<FunctionType>();
16477
16478	FunctionType::ExtInfo Ext = FTy->getExtInfo();
16479	if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(noReturn: true);
16480
16481	// Turn protoless block types into nullary block types.
16482	if (isa<FunctionNoProtoType>(Val: FTy)) {
16483	FunctionProtoType::ExtProtoInfo EPI;
16484	EPI.ExtInfo = Ext;
16485	BlockTy = Context.getFunctionType(ResultTy: RetTy, Args: {}, EPI);
16486
16487	// Otherwise, if we don't need to change anything about the function type,
16488	// preserve its sugar structure.
16489	} else if (FTy->getReturnType() == RetTy &&
16490	(!NoReturn || FTy->getNoReturnAttr())) {
16491	BlockTy = BSI->FunctionType;
16492
16493	// Otherwise, make the minimal modifications to the function type.
16494	} else {
16495	const FunctionProtoType *FPT = cast<FunctionProtoType>(Val: FTy);
16496	FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
16497	EPI.TypeQuals = Qualifiers();
16498	EPI.ExtInfo = Ext;
16499	BlockTy = Context.getFunctionType(ResultTy: RetTy, Args: FPT->getParamTypes(), EPI);
16500	}
16501
16502	// If we don't have a function type, just build one from nothing.
16503	} else {
16504	FunctionProtoType::ExtProtoInfo EPI;
16505	EPI.ExtInfo = FunctionType::ExtInfo().withNoReturn(noReturn: NoReturn);
16506	BlockTy = Context.getFunctionType(ResultTy: RetTy, Args: {}, EPI);
16507	}
16508
16509	DiagnoseUnusedParameters(Parameters: BD->parameters());
16510	BlockTy = Context.getBlockPointerType(T: BlockTy);
16511
16512	// If needed, diagnose invalid gotos and switches in the block.
16513	if (getCurFunction()->NeedsScopeChecking() &&
16514	!PP.isCodeCompletionEnabled())
16515	DiagnoseInvalidJumps(Body: cast<CompoundStmt>(Val: Body));
16516
16517	BD->setBody(cast<CompoundStmt>(Val: Body));
16518
16519	if (Body && getCurFunction()->HasPotentialAvailabilityViolations)
16520	DiagnoseUnguardedAvailabilityViolations(FD: BD);
16521
16522	// Try to apply the named return value optimization. We have to check again
16523	// if we can do this, though, because blocks keep return statements around
16524	// to deduce an implicit return type.
16525	if (getLangOpts().CPlusPlus && RetTy->isRecordType() &&
16526	!BD->isDependentContext())
16527	computeNRVO(Body, Scope: BSI);
16528
16529	if (RetTy.hasNonTrivialToPrimitiveDestructCUnion() ||
16530	RetTy.hasNonTrivialToPrimitiveCopyCUnion())
16531	checkNonTrivialCUnion(QT: RetTy, Loc: BD->getCaretLocation(),
16532	UseContext: NonTrivialCUnionContext::FunctionReturn,
16533	NonTrivialKind: NTCUK_Destruct | NTCUK_Copy);
16534
16535	PopDeclContext();
16536
16537	// Set the captured variables on the block.
16538	SmallVector<BlockDecl::Capture, 4> Captures;
16539	for (Capture &Cap : BSI->Captures) {
16540	if (Cap.isInvalid() || Cap.isThisCapture())
16541	continue;
16542	// Cap.getVariable() is always a VarDecl because
16543	// blocks cannot capture structured bindings or other ValueDecl kinds.
16544	auto *Var = cast<VarDecl>(Val: Cap.getVariable());
16545	Expr *CopyExpr = nullptr;
16546	if (getLangOpts().CPlusPlus && Cap.isCopyCapture()) {
16547	if (const RecordType *Record =
16548	Cap.getCaptureType()->getAs<RecordType>()) {
16549	// The capture logic needs the destructor, so make sure we mark it.
16550	// Usually this is unnecessary because most local variables have
16551	// their destructors marked at declaration time, but parameters are
16552	// an exception because it's technically only the call site that
16553	// actually requires the destructor.
16554	if (isa<ParmVarDecl>(Val: Var))
16555	FinalizeVarWithDestructor(VD: Var, DeclInitType: Record);
16556
16557	// Enter a separate potentially-evaluated context while building block
16558	// initializers to isolate their cleanups from those of the block
16559	// itself.
16560	// FIXME: Is this appropriate even when the block itself occurs in an
16561	// unevaluated operand?
16562	EnterExpressionEvaluationContext EvalContext(
16563	*this, ExpressionEvaluationContext::PotentiallyEvaluated);
16564
16565	SourceLocation Loc = Cap.getLocation();
16566
16567	ExprResult Result = BuildDeclarationNameExpr(
16568	SS: CXXScopeSpec(), NameInfo: DeclarationNameInfo(Var->getDeclName(), Loc), D: Var);
16569
16570	// According to the blocks spec, the capture of a variable from
16571	// the stack requires a const copy constructor. This is not true
16572	// of the copy/move done to move a __block variable to the heap.
16573	if (!Result.isInvalid() &&
16574	!Result.get()->getType().isConstQualified()) {
16575	Result = ImpCastExprToType(E: Result.get(),
16576	Type: Result.get()->getType().withConst(),
16577	CK: CK_NoOp, VK: VK_LValue);
16578	}
16579
16580	if (!Result.isInvalid()) {
16581	Result = PerformCopyInitialization(
16582	Entity: InitializedEntity::InitializeBlock(BlockVarLoc: Var->getLocation(),
16583	Type: Cap.getCaptureType()),
16584	EqualLoc: Loc, Init: Result.get());
16585	}
16586
16587	// Build a full-expression copy expression if initialization
16588	// succeeded and used a non-trivial constructor. Recover from
16589	// errors by pretending that the copy isn't necessary.
16590	if (!Result.isInvalid() &&
16591	!cast<CXXConstructExpr>(Val: Result.get())->getConstructor()
16592	->isTrivial()) {
16593	Result = MaybeCreateExprWithCleanups(SubExpr: Result);
16594	CopyExpr = Result.get();
16595	}
16596	}
16597	}
16598
16599	BlockDecl::Capture NewCap(Var, Cap.isBlockCapture(), Cap.isNested(),
16600	CopyExpr);
16601	Captures.push_back(Elt: NewCap);
16602	}
16603	BD->setCaptures(Context, Captures, CapturesCXXThis: BSI->CXXThisCaptureIndex != 0);
16604
16605	// Pop the block scope now but keep it alive to the end of this function.
16606	AnalysisBasedWarnings::Policy WP =
16607	AnalysisWarnings.getPolicyInEffectAt(Loc: Body->getEndLoc());
16608	PoppedFunctionScopePtr ScopeRAII = PopFunctionScopeInfo(WP: &WP, D: BD, BlockType: BlockTy);
16609
16610	BlockExpr *Result = new (Context)
16611	BlockExpr(BD, BlockTy, BSI->ContainsUnexpandedParameterPack);
16612
16613	// If the block isn't obviously global, i.e. it captures anything at
16614	// all, then we need to do a few things in the surrounding context:
16615	if (Result->getBlockDecl()->hasCaptures()) {
16616	// First, this expression has a new cleanup object.
16617	ExprCleanupObjects.push_back(Elt: Result->getBlockDecl());
16618	Cleanup.setExprNeedsCleanups(true);
16619
16620	// It also gets a branch-protected scope if any of the captured
16621	// variables needs destruction.
16622	for (const auto &CI : Result->getBlockDecl()->captures()) {
16623	const VarDecl *var = CI.getVariable();
16624	if (var->getType().isDestructedType() != QualType::DK_none) {
16625	setFunctionHasBranchProtectedScope();
16626	break;
16627	}
16628	}
16629	}
16630
16631	if (getCurFunction())
16632	getCurFunction()->addBlock(BD);
16633
16634	// This can happen if the block's return type is deduced, but
16635	// the return expression is invalid.
16636	if (BD->isInvalidDecl())
16637	return CreateRecoveryExpr(Begin: Result->getBeginLoc(), End: Result->getEndLoc(),
16638	SubExprs: {Result}, T: Result->getType());
16639	return Result;
16640	}
16641
16642	ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, Expr *E, ParsedType Ty,
16643	SourceLocation RPLoc) {
16644	TypeSourceInfo *TInfo;
16645	GetTypeFromParser(Ty, TInfo: &TInfo);
16646	return BuildVAArgExpr(BuiltinLoc, E, TInfo, RPLoc);
16647	}
16648
16649	ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc,
16650	Expr *E, TypeSourceInfo *TInfo,
16651	SourceLocation RPLoc) {
16652	Expr *OrigExpr = E;
16653	bool IsMS = false;
16654
16655	// CUDA device code does not support varargs.
16656	if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) {
16657	if (const FunctionDecl *F = dyn_cast<FunctionDecl>(Val: CurContext)) {
16658	CUDAFunctionTarget T = CUDA().IdentifyTarget(D: F);
16659	if (T == CUDAFunctionTarget::Global || T == CUDAFunctionTarget::Device ||
16660	T == CUDAFunctionTarget::HostDevice)
16661	return ExprError(Diag(Loc: E->getBeginLoc(), DiagID: diag::err_va_arg_in_device));
16662	}
16663	}
16664
16665	// NVPTX does not support va_arg expression.
16666	if (getLangOpts().OpenMP && getLangOpts().OpenMPIsTargetDevice &&
16667	Context.getTargetInfo().getTriple().isNVPTX())
16668	targetDiag(Loc: E->getBeginLoc(), DiagID: diag::err_va_arg_in_device);
16669
16670	// It might be a __builtin_ms_va_list. (But don't ever mark a va_arg()
16671	// as Microsoft ABI on an actual Microsoft platform, where
16672	// __builtin_ms_va_list and __builtin_va_list are the same.)
16673	if (!E->isTypeDependent() && Context.getTargetInfo().hasBuiltinMSVaList() &&
16674	Context.getTargetInfo().getBuiltinVaListKind() != TargetInfo::CharPtrBuiltinVaList) {
16675	QualType MSVaListType = Context.getBuiltinMSVaListType();
16676	if (Context.hasSameType(T1: MSVaListType, T2: E->getType())) {
16677	if (CheckForModifiableLvalue(E, Loc: BuiltinLoc, S&: *this))
16678	return ExprError();
16679	IsMS = true;
16680	}
16681	}
16682
16683	// Get the va_list type
16684	QualType VaListType = Context.getBuiltinVaListType();
16685	if (!IsMS) {
16686	if (VaListType->isArrayType()) {
16687	// Deal with implicit array decay; for example, on x86-64,
16688	// va_list is an array, but it's supposed to decay to
16689	// a pointer for va_arg.
16690	VaListType = Context.getArrayDecayedType(T: VaListType);
16691	// Make sure the input expression also decays appropriately.
16692	ExprResult Result = UsualUnaryConversions(E);
16693	if (Result.isInvalid())
16694	return ExprError();
16695	E = Result.get();
16696	} else if (VaListType->isRecordType() && getLangOpts().CPlusPlus) {
16697	// If va_list is a record type and we are compiling in C++ mode,
16698	// check the argument using reference binding.
16699	InitializedEntity Entity = InitializedEntity::InitializeParameter(
16700	Context, Type: Context.getLValueReferenceType(T: VaListType), Consumed: false);
16701	ExprResult Init = PerformCopyInitialization(Entity, EqualLoc: SourceLocation(), Init: E);
16702	if (Init.isInvalid())
16703	return ExprError();
16704	E = Init.getAs<Expr>();
16705	} else {
16706	// Otherwise, the va_list argument must be an l-value because
16707	// it is modified by va_arg.
16708	if (!E->isTypeDependent() &&
16709	CheckForModifiableLvalue(E, Loc: BuiltinLoc, S&: *this))
16710	return ExprError();
16711	}
16712	}
16713
16714	if (!IsMS && !E->isTypeDependent() &&
16715	!Context.hasSameType(T1: VaListType, T2: E->getType()))
16716	return ExprError(
16717	Diag(Loc: E->getBeginLoc(),
16718	DiagID: diag::err_first_argument_to_va_arg_not_of_type_va_list)
16719	<< OrigExpr->getType() << E->getSourceRange());
16720
16721	if (!TInfo->getType()->isDependentType()) {
16722	if (RequireCompleteType(Loc: TInfo->getTypeLoc().getBeginLoc(), T: TInfo->getType(),
16723	DiagID: diag::err_second_parameter_to_va_arg_incomplete,
16724	Args: TInfo->getTypeLoc()))
16725	return ExprError();
16726
16727	if (RequireNonAbstractType(Loc: TInfo->getTypeLoc().getBeginLoc(),
16728	T: TInfo->getType(),
16729	DiagID: diag::err_second_parameter_to_va_arg_abstract,
16730	Args: TInfo->getTypeLoc()))
16731	return ExprError();
16732
16733	if (!TInfo->getType().isPODType(Context)) {
16734	Diag(Loc: TInfo->getTypeLoc().getBeginLoc(),
16735	DiagID: TInfo->getType()->isObjCLifetimeType()
16736	? diag::warn_second_parameter_to_va_arg_ownership_qualified
16737	: diag::warn_second_parameter_to_va_arg_not_pod)
16738	<< TInfo->getType()
16739	<< TInfo->getTypeLoc().getSourceRange();
16740	}
16741
16742	if (TInfo->getType()->isArrayType()) {
16743	DiagRuntimeBehavior(Loc: TInfo->getTypeLoc().getBeginLoc(), Statement: E,
16744	PD: PDiag(DiagID: diag::warn_second_parameter_to_va_arg_array)
16745	<< TInfo->getType()
16746	<< TInfo->getTypeLoc().getSourceRange());
16747	}
16748
16749	// Check for va_arg where arguments of the given type will be promoted
16750	// (i.e. this va_arg is guaranteed to have undefined behavior).
16751	QualType PromoteType;
16752	if (Context.isPromotableIntegerType(T: TInfo->getType())) {
16753	PromoteType = Context.getPromotedIntegerType(PromotableType: TInfo->getType());
16754	// [cstdarg.syn]p1 defers the C++ behavior to what the C standard says,
16755	// and C23 7.16.1.1p2 says, in part:
16756	// If type is not compatible with the type of the actual next argument
16757	// (as promoted according to the default argument promotions), the
16758	// behavior is undefined, except for the following cases:
16759	// - both types are pointers to qualified or unqualified versions of
16760	// compatible types;
16761	// - one type is compatible with a signed integer type, the other
16762	// type is compatible with the corresponding unsigned integer type,
16763	// and the value is representable in both types;
16764	// - one type is pointer to qualified or unqualified void and the
16765	// other is a pointer to a qualified or unqualified character type;
16766	// - or, the type of the next argument is nullptr_t and type is a
16767	// pointer type that has the same representation and alignment
16768	// requirements as a pointer to a character type.
16769	// Given that type compatibility is the primary requirement (ignoring
16770	// qualifications), you would think we could call typesAreCompatible()
16771	// directly to test this. However, in C++, that checks for *same type*,
16772	// which causes false positives when passing an enumeration type to
16773	// va_arg. Instead, get the underlying type of the enumeration and pass
16774	// that.
16775	QualType UnderlyingType = TInfo->getType();
16776	if (const auto *ET = UnderlyingType->getAs<EnumType>())
16777	UnderlyingType = ET->getDecl()->getIntegerType();
16778	if (Context.typesAreCompatible(T1: PromoteType, T2: UnderlyingType,
16779	/*CompareUnqualified*/ true))
16780	PromoteType = QualType();
16781
16782	// If the types are still not compatible, we need to test whether the
16783	// promoted type and the underlying type are the same except for
16784	// signedness. Ask the AST for the correctly corresponding type and see
16785	// if that's compatible.
16786	if (!PromoteType.isNull() && !UnderlyingType->isBooleanType() &&
16787	PromoteType->isUnsignedIntegerType() !=
16788	UnderlyingType->isUnsignedIntegerType()) {
16789	UnderlyingType =
16790	UnderlyingType->isUnsignedIntegerType()
16791	? Context.getCorrespondingSignedType(T: UnderlyingType)
16792	: Context.getCorrespondingUnsignedType(T: UnderlyingType);
16793	if (Context.typesAreCompatible(T1: PromoteType, T2: UnderlyingType,
16794	/*CompareUnqualified*/ true))
16795	PromoteType = QualType();
16796	}
16797	}
16798	if (TInfo->getType()->isSpecificBuiltinType(K: BuiltinType::Float))
16799	PromoteType = Context.DoubleTy;
16800	if (!PromoteType.isNull())
16801	DiagRuntimeBehavior(Loc: TInfo->getTypeLoc().getBeginLoc(), Statement: E,
16802	PD: PDiag(DiagID: diag::warn_second_parameter_to_va_arg_never_compatible)
16803	<< TInfo->getType()
16804	<< PromoteType
16805	<< TInfo->getTypeLoc().getSourceRange());
16806	}
16807
16808	QualType T = TInfo->getType().getNonLValueExprType(Context);
16809	return new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T, IsMS);
16810	}
16811
16812	ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) {
16813	// The type of __null will be int or long, depending on the size of
16814	// pointers on the target.
16815	QualType Ty;
16816	unsigned pw = Context.getTargetInfo().getPointerWidth(AddrSpace: LangAS::Default);
16817	if (pw == Context.getTargetInfo().getIntWidth())
16818	Ty = Context.IntTy;
16819	else if (pw == Context.getTargetInfo().getLongWidth())
16820	Ty = Context.LongTy;
16821	else if (pw == Context.getTargetInfo().getLongLongWidth())
16822	Ty = Context.LongLongTy;
16823	else {
16824	llvm_unreachable("I don't know size of pointer!");
16825	}
16826
16827	return new (Context) GNUNullExpr(Ty, TokenLoc);
16828	}
16829
16830	static CXXRecordDecl *LookupStdSourceLocationImpl(Sema &S, SourceLocation Loc) {
16831	CXXRecordDecl *ImplDecl = nullptr;
16832
16833	// Fetch the std::source_location::__impl decl.
16834	if (NamespaceDecl *Std = S.getStdNamespace()) {
16835	LookupResult ResultSL(S, &S.PP.getIdentifierTable().get(Name: "source_location"),
16836	Loc, Sema::LookupOrdinaryName);
16837	if (S.LookupQualifiedName(R&: ResultSL, LookupCtx: Std)) {
16838	if (auto *SLDecl = ResultSL.getAsSingle<RecordDecl>()) {
16839	LookupResult ResultImpl(S, &S.PP.getIdentifierTable().get(Name: "__impl"),
16840	Loc, Sema::LookupOrdinaryName);
16841	if ((SLDecl->isCompleteDefinition() || SLDecl->isBeingDefined()) &&
16842	S.LookupQualifiedName(R&: ResultImpl, LookupCtx: SLDecl)) {
16843	ImplDecl = ResultImpl.getAsSingle<CXXRecordDecl>();
16844	}
16845	}
16846	}
16847	}
16848
16849	if (!ImplDecl || !ImplDecl->isCompleteDefinition()) {
16850	S.Diag(Loc, DiagID: diag::err_std_source_location_impl_not_found);
16851	return nullptr;
16852	}
16853
16854	// Verify that __impl is a trivial struct type, with no base classes, and with
16855	// only the four expected fields.
16856	if (ImplDecl->isUnion() || !ImplDecl->isStandardLayout() ||
16857	ImplDecl->getNumBases() != 0) {
16858	S.Diag(Loc, DiagID: diag::err_std_source_location_impl_malformed);
16859	return nullptr;
16860	}
16861
16862	unsigned Count = 0;
16863	for (FieldDecl *F : ImplDecl->fields()) {
16864	StringRef Name = F->getName();
16865
16866	if (Name == "_M_file_name") {
16867	if (F->getType() !=
16868	S.Context.getPointerType(T: S.Context.CharTy.withConst()))
16869	break;
16870	Count++;
16871	} else if (Name == "_M_function_name") {
16872	if (F->getType() !=
16873	S.Context.getPointerType(T: S.Context.CharTy.withConst()))
16874	break;
16875	Count++;
16876	} else if (Name == "_M_line") {
16877	if (!F->getType()->isIntegerType())
16878	break;
16879	Count++;
16880	} else if (Name == "_M_column") {
16881	if (!F->getType()->isIntegerType())
16882	break;
16883	Count++;
16884	} else {
16885	Count = 100; // invalid
16886	break;
16887	}
16888	}
16889	if (Count != 4) {
16890	S.Diag(Loc, DiagID: diag::err_std_source_location_impl_malformed);
16891	return nullptr;
16892	}
16893
16894	return ImplDecl;
16895	}
16896
16897	ExprResult Sema::ActOnSourceLocExpr(SourceLocIdentKind Kind,
16898	SourceLocation BuiltinLoc,
16899	SourceLocation RPLoc) {
16900	QualType ResultTy;
16901	switch (Kind) {
16902	case SourceLocIdentKind::File:
16903	case SourceLocIdentKind::FileName:
16904	case SourceLocIdentKind::Function:
16905	case SourceLocIdentKind::FuncSig: {
16906	QualType ArrTy = Context.getStringLiteralArrayType(EltTy: Context.CharTy, Length: 0);
16907	ResultTy =
16908	Context.getPointerType(T: ArrTy->getAsArrayTypeUnsafe()->getElementType());
16909	break;
16910	}
16911	case SourceLocIdentKind::Line:
16912	case SourceLocIdentKind::Column:
16913	ResultTy = Context.UnsignedIntTy;
16914	break;
16915	case SourceLocIdentKind::SourceLocStruct:
16916	if (!StdSourceLocationImplDecl) {
16917	StdSourceLocationImplDecl =
16918	LookupStdSourceLocationImpl(S&: *this, Loc: BuiltinLoc);
16919	if (!StdSourceLocationImplDecl)
16920	return ExprError();
16921	}
16922	ResultTy = Context.getPointerType(
16923	T: Context.getRecordType(Decl: StdSourceLocationImplDecl).withConst());
16924	break;
16925	}
16926
16927	return BuildSourceLocExpr(Kind, ResultTy, BuiltinLoc, RPLoc, ParentContext: CurContext);
16928	}
16929
16930	ExprResult Sema::BuildSourceLocExpr(SourceLocIdentKind Kind, QualType ResultTy,
16931	SourceLocation BuiltinLoc,
16932	SourceLocation RPLoc,
16933	DeclContext *ParentContext) {
16934	return new (Context)
16935	SourceLocExpr(Context, Kind, ResultTy, BuiltinLoc, RPLoc, ParentContext);
16936	}
16937
16938	ExprResult Sema::ActOnEmbedExpr(SourceLocation EmbedKeywordLoc,
16939	StringLiteral *BinaryData, StringRef FileName) {
16940	EmbedDataStorage *Data = new (Context) EmbedDataStorage;
16941	Data->BinaryData = BinaryData;
16942	Data->FileName = FileName;
16943	return new (Context)
16944	EmbedExpr(Context, EmbedKeywordLoc, Data, /*NumOfElements=*/0,
16945	Data->getDataElementCount());
16946	}
16947
16948	static bool maybeDiagnoseAssignmentToFunction(Sema &S, QualType DstType,
16949	const Expr *SrcExpr) {
16950	if (!DstType->isFunctionPointerType() ||
16951	!SrcExpr->getType()->isFunctionType())
16952	return false;
16953
16954	auto *DRE = dyn_cast<DeclRefExpr>(Val: SrcExpr->IgnoreParenImpCasts());
16955	if (!DRE)
16956	return false;
16957
16958	auto *FD = dyn_cast<FunctionDecl>(Val: DRE->getDecl());
16959	if (!FD)
16960	return false;
16961
16962	return !S.checkAddressOfFunctionIsAvailable(Function: FD,
16963	/*Complain=*/true,
16964	Loc: SrcExpr->getBeginLoc());
16965	}
16966
16967	bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy,
16968	SourceLocation Loc,
16969	QualType DstType, QualType SrcType,
16970	Expr *SrcExpr, AssignmentAction Action,
16971	bool *Complained) {
16972	if (Complained)
16973	*Complained = false;
16974
16975	// Decode the result (notice that AST's are still created for extensions).
16976	bool CheckInferredResultType = false;
16977	bool isInvalid = false;
16978	unsigned DiagKind = 0;
16979	ConversionFixItGenerator ConvHints;
16980	bool MayHaveConvFixit = false;
16981	bool MayHaveFunctionDiff = false;
16982	const ObjCInterfaceDecl *IFace = nullptr;
16983	const ObjCProtocolDecl *PDecl = nullptr;
16984
16985	switch (ConvTy) {
16986	case AssignConvertType::Compatible:
16987	DiagnoseAssignmentEnum(DstType, SrcType, SrcExpr);
16988	return false;
16989	case AssignConvertType::CompatibleVoidPtrToNonVoidPtr:
16990	// Still a valid conversion, but we may want to diagnose for C++
16991	// compatibility reasons.
16992	DiagKind = diag::warn_compatible_implicit_pointer_conv;
16993	break;
16994	case AssignConvertType::PointerToInt:
16995	if (getLangOpts().CPlusPlus) {
16996	DiagKind = diag::err_typecheck_convert_pointer_int;
16997	isInvalid = true;
16998	} else {
16999	DiagKind = diag::ext_typecheck_convert_pointer_int;
17000	}
17001	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17002	MayHaveConvFixit = true;
17003	break;
17004	case AssignConvertType::IntToPointer:
17005	if (getLangOpts().CPlusPlus) {
17006	DiagKind = diag::err_typecheck_convert_int_pointer;
17007	isInvalid = true;
17008	} else {
17009	DiagKind = diag::ext_typecheck_convert_int_pointer;
17010	}
17011	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17012	MayHaveConvFixit = true;
17013	break;
17014	case AssignConvertType::IncompatibleFunctionPointerStrict:
17015	DiagKind =
17016	diag::warn_typecheck_convert_incompatible_function_pointer_strict;
17017	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17018	MayHaveConvFixit = true;
17019	break;
17020	case AssignConvertType::IncompatibleFunctionPointer:
17021	if (getLangOpts().CPlusPlus) {
17022	DiagKind = diag::err_typecheck_convert_incompatible_function_pointer;
17023	isInvalid = true;
17024	} else {
17025	DiagKind = diag::ext_typecheck_convert_incompatible_function_pointer;
17026	}
17027	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17028	MayHaveConvFixit = true;
17029	break;
17030	case AssignConvertType::IncompatiblePointer:
17031	if (Action == AssignmentAction::Passing_CFAudited) {
17032	DiagKind = diag::err_arc_typecheck_convert_incompatible_pointer;
17033	} else if (getLangOpts().CPlusPlus) {
17034	DiagKind = diag::err_typecheck_convert_incompatible_pointer;
17035	isInvalid = true;
17036	} else {
17037	DiagKind = diag::ext_typecheck_convert_incompatible_pointer;
17038	}
17039	CheckInferredResultType = DstType->isObjCObjectPointerType() &&
17040	SrcType->isObjCObjectPointerType();
17041	if (CheckInferredResultType) {
17042	SrcType = SrcType.getUnqualifiedType();
17043	DstType = DstType.getUnqualifiedType();
17044	} else {
17045	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17046	}
17047	MayHaveConvFixit = true;
17048	break;
17049	case AssignConvertType::IncompatiblePointerSign:
17050	if (getLangOpts().CPlusPlus) {
17051	DiagKind = diag::err_typecheck_convert_incompatible_pointer_sign;
17052	isInvalid = true;
17053	} else {
17054	DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign;
17055	}
17056	break;
17057	case AssignConvertType::FunctionVoidPointer:
17058	if (getLangOpts().CPlusPlus) {
17059	DiagKind = diag::err_typecheck_convert_pointer_void_func;
17060	isInvalid = true;
17061	} else {
17062	DiagKind = diag::ext_typecheck_convert_pointer_void_func;
17063	}
17064	break;
17065	case AssignConvertType::IncompatiblePointerDiscardsQualifiers: {
17066	// Perform array-to-pointer decay if necessary.
17067	if (SrcType->isArrayType()) SrcType = Context.getArrayDecayedType(T: SrcType);
17068
17069	isInvalid = true;
17070
17071	Qualifiers lhq = SrcType->getPointeeType().getQualifiers();
17072	Qualifiers rhq = DstType->getPointeeType().getQualifiers();
17073	if (lhq.getAddressSpace() != rhq.getAddressSpace()) {
17074	DiagKind = diag::err_typecheck_incompatible_address_space;
17075	break;
17076	} else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) {
17077	DiagKind = diag::err_typecheck_incompatible_ownership;
17078	break;
17079	} else if (!lhq.getPointerAuth().isEquivalent(Other: rhq.getPointerAuth())) {
17080	DiagKind = diag::err_typecheck_incompatible_ptrauth;
17081	break;
17082	}
17083
17084	llvm_unreachable("unknown error case for discarding qualifiers!");
17085	// fallthrough
17086	}
17087	case AssignConvertType::CompatiblePointerDiscardsQualifiers:
17088	// If the qualifiers lost were because we were applying the
17089	// (deprecated) C++ conversion from a string literal to a char*
17090	// (or wchar_t*), then there was no error (C++ 4.2p2). FIXME:
17091	// Ideally, this check would be performed in
17092	// checkPointerTypesForAssignment. However, that would require a
17093	// bit of refactoring (so that the second argument is an
17094	// expression, rather than a type), which should be done as part
17095	// of a larger effort to fix checkPointerTypesForAssignment for
17096	// C++ semantics.
17097	if (getLangOpts().CPlusPlus &&
17098	IsStringLiteralToNonConstPointerConversion(From: SrcExpr, ToType: DstType))
17099	return false;
17100	if (getLangOpts().CPlusPlus) {
17101	DiagKind = diag::err_typecheck_convert_discards_qualifiers;
17102	isInvalid = true;
17103	} else {
17104	DiagKind = diag::ext_typecheck_convert_discards_qualifiers;
17105	}
17106
17107	break;
17108	case AssignConvertType::IncompatibleNestedPointerQualifiers:
17109	if (getLangOpts().CPlusPlus) {
17110	isInvalid = true;
17111	DiagKind = diag::err_nested_pointer_qualifier_mismatch;
17112	} else {
17113	DiagKind = diag::ext_nested_pointer_qualifier_mismatch;
17114	}
17115	break;
17116	case AssignConvertType::IncompatibleNestedPointerAddressSpaceMismatch:
17117	DiagKind = diag::err_typecheck_incompatible_nested_address_space;
17118	isInvalid = true;
17119	break;
17120	case AssignConvertType::IntToBlockPointer:
17121	DiagKind = diag::err_int_to_block_pointer;
17122	isInvalid = true;
17123	break;
17124	case AssignConvertType::IncompatibleBlockPointer:
17125	DiagKind = diag::err_typecheck_convert_incompatible_block_pointer;
17126	isInvalid = true;
17127	break;
17128	case AssignConvertType::IncompatibleObjCQualifiedId: {
17129	if (SrcType->isObjCQualifiedIdType()) {
17130	const ObjCObjectPointerType *srcOPT =
17131	SrcType->castAs<ObjCObjectPointerType>();
17132	for (auto *srcProto : srcOPT->quals()) {
17133	PDecl = srcProto;
17134	break;
17135	}
17136	if (const ObjCInterfaceType *IFaceT =
17137	DstType->castAs<ObjCObjectPointerType>()->getInterfaceType())
17138	IFace = IFaceT->getDecl();
17139	}
17140	else if (DstType->isObjCQualifiedIdType()) {
17141	const ObjCObjectPointerType *dstOPT =
17142	DstType->castAs<ObjCObjectPointerType>();
17143	for (auto *dstProto : dstOPT->quals()) {
17144	PDecl = dstProto;
17145	break;
17146	}
17147	if (const ObjCInterfaceType *IFaceT =
17148	SrcType->castAs<ObjCObjectPointerType>()->getInterfaceType())
17149	IFace = IFaceT->getDecl();
17150	}
17151	if (getLangOpts().CPlusPlus) {
17152	DiagKind = diag::err_incompatible_qualified_id;
17153	isInvalid = true;
17154	} else {
17155	DiagKind = diag::warn_incompatible_qualified_id;
17156	}
17157	break;
17158	}
17159	case AssignConvertType::IncompatibleVectors:
17160	if (getLangOpts().CPlusPlus) {
17161	DiagKind = diag::err_incompatible_vectors;
17162	isInvalid = true;
17163	} else {
17164	DiagKind = diag::warn_incompatible_vectors;
17165	}
17166	break;
17167	case AssignConvertType::IncompatibleObjCWeakRef:
17168	DiagKind = diag::err_arc_weak_unavailable_assign;
17169	isInvalid = true;
17170	break;
17171	case AssignConvertType::Incompatible:
17172	if (maybeDiagnoseAssignmentToFunction(S&: *this, DstType, SrcExpr)) {
17173	if (Complained)
17174	*Complained = true;
17175	return true;
17176	}
17177
17178	DiagKind = diag::err_typecheck_convert_incompatible;
17179	ConvHints.tryToFixConversion(FromExpr: SrcExpr, FromQTy: SrcType, ToQTy: DstType, S&: *this);
17180	MayHaveConvFixit = true;
17181	isInvalid = true;
17182	MayHaveFunctionDiff = true;
17183	break;
17184	}
17185
17186	QualType FirstType, SecondType;
17187	switch (Action) {
17188	case AssignmentAction::Assigning:
17189	case AssignmentAction::Initializing:
17190	// The destination type comes first.
17191	FirstType = DstType;
17192	SecondType = SrcType;
17193	break;
17194
17195	case AssignmentAction::Returning:
17196	case AssignmentAction::Passing:
17197	case AssignmentAction::Passing_CFAudited:
17198	case AssignmentAction::Converting:
17199	case AssignmentAction::Sending:
17200	case AssignmentAction::Casting:
17201	// The source type comes first.
17202	FirstType = SrcType;
17203	SecondType = DstType;
17204	break;
17205	}
17206
17207	PartialDiagnostic FDiag = PDiag(DiagID: DiagKind);
17208	AssignmentAction ActionForDiag = Action;
17209	if (Action == AssignmentAction::Passing_CFAudited)
17210	ActionForDiag = AssignmentAction::Passing;
17211
17212	FDiag << FirstType << SecondType << ActionForDiag
17213	<< SrcExpr->getSourceRange();
17214
17215	if (DiagKind == diag::ext_typecheck_convert_incompatible_pointer_sign ||
17216	DiagKind == diag::err_typecheck_convert_incompatible_pointer_sign) {
17217	auto isPlainChar = [](const clang::Type *Type) {
17218	return Type->isSpecificBuiltinType(K: BuiltinType::Char_S) ||
17219	Type->isSpecificBuiltinType(K: BuiltinType::Char_U);
17220	};
17221	FDiag << (isPlainChar(FirstType->getPointeeOrArrayElementType()) ||
17222	isPlainChar(SecondType->getPointeeOrArrayElementType()));
17223	}
17224
17225	// If we can fix the conversion, suggest the FixIts.
17226	if (!ConvHints.isNull()) {
17227	for (FixItHint &H : ConvHints.Hints)
17228	FDiag << H;
17229	}
17230
17231	if (MayHaveConvFixit) { FDiag << (unsigned) (ConvHints.Kind); }
17232
17233	if (MayHaveFunctionDiff)
17234	HandleFunctionTypeMismatch(PDiag&: FDiag, FromType: SecondType, ToType: FirstType);
17235
17236	Diag(Loc, PD: FDiag);
17237	if ((DiagKind == diag::warn_incompatible_qualified_id ||
17238	DiagKind == diag::err_incompatible_qualified_id) &&
17239	PDecl && IFace && !IFace->hasDefinition())
17240	Diag(Loc: IFace->getLocation(), DiagID: diag::note_incomplete_class_and_qualified_id)
17241	<< IFace << PDecl;
17242
17243	if (SecondType == Context.OverloadTy)
17244	NoteAllOverloadCandidates(E: OverloadExpr::find(E: SrcExpr).Expression,
17245	DestType: FirstType, /*TakingAddress=*/true);
17246
17247	if (CheckInferredResultType)
17248	ObjC().EmitRelatedResultTypeNote(E: SrcExpr);
17249
17250	if (Action == AssignmentAction::Returning &&
17251	ConvTy == AssignConvertType::IncompatiblePointer)
17252	ObjC().EmitRelatedResultTypeNoteForReturn(destType: DstType);
17253
17254	if (Complained)
17255	*Complained = true;
17256	return isInvalid;
17257	}
17258
17259	ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
17260	llvm::APSInt *Result,
17261	AllowFoldKind CanFold) {
17262	class SimpleICEDiagnoser : public VerifyICEDiagnoser {
17263	public:
17264	SemaDiagnosticBuilder diagnoseNotICEType(Sema &S, SourceLocation Loc,
17265	QualType T) override {
17266	return S.Diag(Loc, DiagID: diag::err_ice_not_integral)
17267	<< T << S.LangOpts.CPlusPlus;
17268	}
17269	SemaDiagnosticBuilder diagnoseNotICE(Sema &S, SourceLocation Loc) override {
17270	return S.Diag(Loc, DiagID: diag::err_expr_not_ice) << S.LangOpts.CPlusPlus;
17271	}
17272	} Diagnoser;
17273
17274	return VerifyIntegerConstantExpression(E, Result, Diagnoser, CanFold);
17275	}
17276
17277	ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
17278	llvm::APSInt *Result,
17279	unsigned DiagID,
17280	AllowFoldKind CanFold) {
17281	class IDDiagnoser : public VerifyICEDiagnoser {
17282	unsigned DiagID;
17283
17284	public:
17285	IDDiagnoser(unsigned DiagID)
17286	: VerifyICEDiagnoser(DiagID == 0), DiagID(DiagID) { }
17287
17288	SemaDiagnosticBuilder diagnoseNotICE(Sema &S, SourceLocation Loc) override {
17289	return S.Diag(Loc, DiagID);
17290	}
17291	} Diagnoser(DiagID);
17292
17293	return VerifyIntegerConstantExpression(E, Result, Diagnoser, CanFold);
17294	}
17295
17296	Sema::SemaDiagnosticBuilder
17297	Sema::VerifyICEDiagnoser::diagnoseNotICEType(Sema &S, SourceLocation Loc,
17298	QualType T) {
17299	return diagnoseNotICE(S, Loc);
17300	}
17301
17302	Sema::SemaDiagnosticBuilder
17303	Sema::VerifyICEDiagnoser::diagnoseFold(Sema &S, SourceLocation Loc) {
17304	return S.Diag(Loc, DiagID: diag::ext_expr_not_ice) << S.LangOpts.CPlusPlus;
17305	}
17306
17307	ExprResult
17308	Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
17309	VerifyICEDiagnoser &Diagnoser,
17310	AllowFoldKind CanFold) {
17311	SourceLocation DiagLoc = E->getBeginLoc();
17312
17313	if (getLangOpts().CPlusPlus11) {
17314	// C++11 [expr.const]p5:
17315	// If an expression of literal class type is used in a context where an
17316	// integral constant expression is required, then that class type shall
17317	// have a single non-explicit conversion function to an integral or
17318	// unscoped enumeration type
17319	ExprResult Converted;
17320	class CXX11ConvertDiagnoser : public ICEConvertDiagnoser {
17321	VerifyICEDiagnoser &BaseDiagnoser;
17322	public:
17323	CXX11ConvertDiagnoser(VerifyICEDiagnoser &BaseDiagnoser)
17324	: ICEConvertDiagnoser(/*AllowScopedEnumerations*/ false,
17325	BaseDiagnoser.Suppress, true),
17326	BaseDiagnoser(BaseDiagnoser) {}
17327
17328	SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
17329	QualType T) override {
17330	return BaseDiagnoser.diagnoseNotICEType(S, Loc, T);
17331	}
17332
17333	SemaDiagnosticBuilder diagnoseIncomplete(
17334	Sema &S, SourceLocation Loc, QualType T) override {
17335	return S.Diag(Loc, DiagID: diag::err_ice_incomplete_type) << T;
17336	}
17337
17338	SemaDiagnosticBuilder diagnoseExplicitConv(
17339	Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
17340	return S.Diag(Loc, DiagID: diag::err_ice_explicit_conversion) << T << ConvTy;
17341	}
17342
17343	SemaDiagnosticBuilder noteExplicitConv(
17344	Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
17345	return S.Diag(Loc: Conv->getLocation(), DiagID: diag::note_ice_conversion_here)
17346	<< ConvTy->isEnumeralType() << ConvTy;
17347	}
17348
17349	SemaDiagnosticBuilder diagnoseAmbiguous(
17350	Sema &S, SourceLocation Loc, QualType T) override {
17351	return S.Diag(Loc, DiagID: diag::err_ice_ambiguous_conversion) << T;
17352	}
17353
17354	SemaDiagnosticBuilder noteAmbiguous(
17355	Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
17356	return S.Diag(Loc: Conv->getLocation(), DiagID: diag::note_ice_conversion_here)
17357	<< ConvTy->isEnumeralType() << ConvTy;
17358	}
17359
17360	SemaDiagnosticBuilder diagnoseConversion(
17361	Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
17362	llvm_unreachable("conversion functions are permitted");
17363	}
17364	} ConvertDiagnoser(Diagnoser);
17365
17366	Converted = PerformContextualImplicitConversion(Loc: DiagLoc, FromE: E,
17367	Converter&: ConvertDiagnoser);
17368	if (Converted.isInvalid())
17369	return Converted;
17370	E = Converted.get();
17371	// The 'explicit' case causes us to get a RecoveryExpr. Give up here so we
17372	// don't try to evaluate it later. We also don't want to return the
17373	// RecoveryExpr here, as it results in this call succeeding, thus callers of
17374	// this function will attempt to use 'Value'.
17375	if (isa<RecoveryExpr>(Val: E))
17376	return ExprError();
17377	if (!E->getType()->isIntegralOrUnscopedEnumerationType())
17378	return ExprError();
17379	} else if (!E->getType()->isIntegralOrUnscopedEnumerationType()) {
17380	// An ICE must be of integral or unscoped enumeration type.
17381	if (!Diagnoser.Suppress)
17382	Diagnoser.diagnoseNotICEType(S&: *this, Loc: DiagLoc, T: E->getType())
17383	<< E->getSourceRange();
17384	return ExprError();
17385	}
17386
17387	ExprResult RValueExpr = DefaultLvalueConversion(E);
17388	if (RValueExpr.isInvalid())
17389	return ExprError();
17390
17391	E = RValueExpr.get();
17392
17393	// Circumvent ICE checking in C++11 to avoid evaluating the expression twice
17394	// in the non-ICE case.
17395	if (!getLangOpts().CPlusPlus11 && E->isIntegerConstantExpr(Ctx: Context)) {
17396	SmallVector<PartialDiagnosticAt, 8> Notes;
17397	if (Result)
17398	*Result = E->EvaluateKnownConstIntCheckOverflow(Ctx: Context, Diag: &Notes);
17399	if (!isa<ConstantExpr>(Val: E))
17400	E = Result ? ConstantExpr::Create(Context, E, Result: APValue(*Result))
17401	: ConstantExpr::Create(Context, E);
17402
17403	if (Notes.empty())
17404	return E;
17405
17406	// If our only note is the usual "invalid subexpression" note, just point
17407	// the caret at its location rather than producing an essentially
17408	// redundant note.
17409	if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
17410	diag::note_invalid_subexpr_in_const_expr) {
17411	DiagLoc = Notes[0].first;
17412	Notes.clear();
17413	}
17414
17415	if (getLangOpts().CPlusPlus) {
17416	if (!Diagnoser.Suppress) {
17417	Diagnoser.diagnoseNotICE(S&: *this, Loc: DiagLoc) << E->getSourceRange();
17418	for (const PartialDiagnosticAt &Note : Notes)
17419	Diag(Loc: Note.first, PD: Note.second);
17420	}
17421	return ExprError();
17422	}
17423
17424	Diagnoser.diagnoseFold(S&: *this, Loc: DiagLoc) << E->getSourceRange();
17425	for (const PartialDiagnosticAt &Note : Notes)
17426	Diag(Loc: Note.first, PD: Note.second);
17427
17428	return E;
17429	}
17430
17431	Expr::EvalResult EvalResult;
17432	SmallVector<PartialDiagnosticAt, 8> Notes;
17433	EvalResult.Diag = &Notes;
17434
17435	// Try to evaluate the expression, and produce diagnostics explaining why it's
17436	// not a constant expression as a side-effect.
17437	bool Folded =
17438	E->EvaluateAsRValue(Result&: EvalResult, Ctx: Context, /*isConstantContext*/ InConstantContext: true) &&
17439	EvalResult.Val.isInt() && !EvalResult.HasSideEffects &&
17440	(!getLangOpts().CPlusPlus || !EvalResult.HasUndefinedBehavior);
17441
17442	if (!isa<ConstantExpr>(Val: E))
17443	E = ConstantExpr::Create(Context, E, Result: EvalResult.Val);
17444
17445	// In C++11, we can rely on diagnostics being produced for any expression
17446	// which is not a constant expression. If no diagnostics were produced, then
17447	// this is a constant expression.
17448	if (Folded && getLangOpts().CPlusPlus11 && Notes.empty()) {
17449	if (Result)
17450	*Result = EvalResult.Val.getInt();
17451	return E;
17452	}
17453
17454	// If our only note is the usual "invalid subexpression" note, just point
17455	// the caret at its location rather than producing an essentially
17456	// redundant note.
17457	if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
17458	diag::note_invalid_subexpr_in_const_expr) {
17459	DiagLoc = Notes[0].first;
17460	Notes.clear();
17461	}
17462
17463	if (!Folded || CanFold == AllowFoldKind::No) {
17464	if (!Diagnoser.Suppress) {
17465	Diagnoser.diagnoseNotICE(S&: *this, Loc: DiagLoc) << E->getSourceRange();
17466	for (const PartialDiagnosticAt &Note : Notes)
17467	Diag(Loc: Note.first, PD: Note.second);
17468	}
17469
17470	return ExprError();
17471	}
17472
17473	Diagnoser.diagnoseFold(S&: *this, Loc: DiagLoc) << E->getSourceRange();
17474	for (const PartialDiagnosticAt &Note : Notes)
17475	Diag(Loc: Note.first, PD: Note.second);
17476
17477	if (Result)
17478	*Result = EvalResult.Val.getInt();
17479	return E;
17480	}
17481
17482	namespace {
17483	// Handle the case where we conclude a expression which we speculatively
17484	// considered to be unevaluated is actually evaluated.
17485	class TransformToPE : public TreeTransform<TransformToPE> {
17486	typedef TreeTransform<TransformToPE> BaseTransform;
17487
17488	public:
17489	TransformToPE(Sema &SemaRef) : BaseTransform(SemaRef) { }
17490
17491	// Make sure we redo semantic analysis
17492	bool AlwaysRebuild() { return true; }
17493	bool ReplacingOriginal() { return true; }
17494
17495	// We need to special-case DeclRefExprs referring to FieldDecls which
17496	// are not part of a member pointer formation; normal TreeTransforming
17497	// doesn't catch this case because of the way we represent them in the AST.
17498	// FIXME: This is a bit ugly; is it really the best way to handle this
17499	// case?
17500	//
17501	// Error on DeclRefExprs referring to FieldDecls.
17502	ExprResult TransformDeclRefExpr(DeclRefExpr *E) {
17503	if (isa<FieldDecl>(Val: E->getDecl()) &&
17504	!SemaRef.isUnevaluatedContext())
17505	return SemaRef.Diag(Loc: E->getLocation(),
17506	DiagID: diag::err_invalid_non_static_member_use)
17507	<< E->getDecl() << E->getSourceRange();
17508
17509	return BaseTransform::TransformDeclRefExpr(E);
17510	}
17511
17512	// Exception: filter out member pointer formation
17513	ExprResult TransformUnaryOperator(UnaryOperator *E) {
17514	if (E->getOpcode() == UO_AddrOf && E->getType()->isMemberPointerType())
17515	return E;
17516
17517	return BaseTransform::TransformUnaryOperator(E);
17518	}
17519
17520	// The body of a lambda-expression is in a separate expression evaluation
17521	// context so never needs to be transformed.
17522	// FIXME: Ideally we wouldn't transform the closure type either, and would
17523	// just recreate the capture expressions and lambda expression.
17524	StmtResult TransformLambdaBody(LambdaExpr *E, Stmt *Body) {
17525	return SkipLambdaBody(E, S: Body);
17526	}
17527	};
17528	}
17529
17530	ExprResult Sema::TransformToPotentiallyEvaluated(Expr *E) {
17531	assert(isUnevaluatedContext() &&
17532	"Should only transform unevaluated expressions");
17533	ExprEvalContexts.back().Context =
17534	ExprEvalContexts[ExprEvalContexts.size()-2].Context;
17535	if (isUnevaluatedContext())
17536	return E;
17537	return TransformToPE(*this).TransformExpr(E);
17538	}
17539
17540	TypeSourceInfo *Sema::TransformToPotentiallyEvaluated(TypeSourceInfo *TInfo) {
17541	assert(isUnevaluatedContext() &&
17542	"Should only transform unevaluated expressions");
17543	ExprEvalContexts.back().Context = parentEvaluationContext().Context;
17544	if (isUnevaluatedContext())
17545	return TInfo;
17546	return TransformToPE(*this).TransformType(DI: TInfo);
17547	}
17548
17549	void
17550	Sema::PushExpressionEvaluationContext(
17551	ExpressionEvaluationContext NewContext, Decl *LambdaContextDecl,
17552	ExpressionEvaluationContextRecord::ExpressionKind ExprContext) {
17553	ExprEvalContexts.emplace_back(Args&: NewContext, Args: ExprCleanupObjects.size(), Args&: Cleanup,
17554	Args&: LambdaContextDecl, Args&: ExprContext);
17555
17556	// Discarded statements and immediate contexts nested in other
17557	// discarded statements or immediate context are themselves
17558	// a discarded statement or an immediate context, respectively.
17559	ExprEvalContexts.back().InDiscardedStatement =
17560	parentEvaluationContext().isDiscardedStatementContext();
17561
17562	// C++23 [expr.const]/p15
17563	// An expression or conversion is in an immediate function context if [...]
17564	// it is a subexpression of a manifestly constant-evaluated expression or
17565	// conversion.
17566	const auto &Prev = parentEvaluationContext();
17567	ExprEvalContexts.back().InImmediateFunctionContext =
17568	Prev.isImmediateFunctionContext() || Prev.isConstantEvaluated();
17569
17570	ExprEvalContexts.back().InImmediateEscalatingFunctionContext =
17571	Prev.InImmediateEscalatingFunctionContext;
17572
17573	Cleanup.reset();
17574	if (!MaybeODRUseExprs.empty())
17575	std::swap(LHS&: MaybeODRUseExprs, RHS&: ExprEvalContexts.back().SavedMaybeODRUseExprs);
17576	}
17577
17578	void
17579	Sema::PushExpressionEvaluationContext(
17580	ExpressionEvaluationContext NewContext, ReuseLambdaContextDecl_t,
17581	ExpressionEvaluationContextRecord::ExpressionKind ExprContext) {
17582	Decl *ClosureContextDecl = ExprEvalContexts.back().ManglingContextDecl;
17583	PushExpressionEvaluationContext(NewContext, LambdaContextDecl: ClosureContextDecl, ExprContext);
17584	}
17585
17586	void Sema::PushExpressionEvaluationContextForFunction(
17587	ExpressionEvaluationContext NewContext, FunctionDecl *FD) {
17588	// [expr.const]/p14.1
17589	// An expression or conversion is in an immediate function context if it is
17590	// potentially evaluated and either: its innermost enclosing non-block scope
17591	// is a function parameter scope of an immediate function.
17592	PushExpressionEvaluationContext(
17593	NewContext: FD && FD->isConsteval()
17594	? ExpressionEvaluationContext::ImmediateFunctionContext
17595	: NewContext);
17596	const Sema::ExpressionEvaluationContextRecord &Parent =
17597	parentEvaluationContext();
17598	Sema::ExpressionEvaluationContextRecord &Current = currentEvaluationContext();
17599
17600	Current.InDiscardedStatement = false;
17601
17602	if (FD) {
17603
17604	// Each ExpressionEvaluationContextRecord also keeps track of whether the
17605	// context is nested in an immediate function context, so smaller contexts
17606	// that appear inside immediate functions (like variable initializers) are
17607	// considered to be inside an immediate function context even though by
17608	// themselves they are not immediate function contexts. But when a new
17609	// function is entered, we need to reset this tracking, since the entered
17610	// function might be not an immediate function.
17611
17612	Current.InImmediateEscalatingFunctionContext =
17613	getLangOpts().CPlusPlus20 && FD->isImmediateEscalating();
17614
17615	if (isLambdaMethod(DC: FD))
17616	Current.InImmediateFunctionContext =
17617	FD->isConsteval() ||
17618	(isLambdaMethod(DC: FD) && (Parent.isConstantEvaluated() ||
17619	Parent.isImmediateFunctionContext()));
17620	else
17621	Current.InImmediateFunctionContext = FD->isConsteval();
17622	}
17623	}
17624
17625	namespace {
17626
17627	const DeclRefExpr *CheckPossibleDeref(Sema &S, const Expr *PossibleDeref) {
17628	PossibleDeref = PossibleDeref->IgnoreParenImpCasts();
17629	if (const auto *E = dyn_cast<UnaryOperator>(Val: PossibleDeref)) {
17630	if (E->getOpcode() == UO_Deref)
17631	return CheckPossibleDeref(S, PossibleDeref: E->getSubExpr());
17632	} else if (const auto *E = dyn_cast<ArraySubscriptExpr>(Val: PossibleDeref)) {
17633	return CheckPossibleDeref(S, PossibleDeref: E->getBase());
17634	} else if (const auto *E = dyn_cast<MemberExpr>(Val: PossibleDeref)) {
17635	return CheckPossibleDeref(S, PossibleDeref: E->getBase());
17636	} else if (const auto E = dyn_cast<DeclRefExpr>(Val: PossibleDeref)) {
17637	QualType Inner;
17638	QualType Ty = E->getType();
17639	if (const auto *Ptr = Ty->getAs<PointerType>())
17640	Inner = Ptr->getPointeeType();
17641	else if (const auto *Arr = S.Context.getAsArrayType(T: Ty))
17642	Inner = Arr->getElementType();
17643	else
17644	return nullptr;
17645
17646	if (Inner->hasAttr(AK: attr::NoDeref))
17647	return E;
17648	}
17649	return nullptr;
17650	}
17651
17652	} // namespace
17653
17654	void Sema::WarnOnPendingNoDerefs(ExpressionEvaluationContextRecord &Rec) {
17655	for (const Expr *E : Rec.PossibleDerefs) {
17656	const DeclRefExpr *DeclRef = CheckPossibleDeref(S&: *this, PossibleDeref: E);
17657	if (DeclRef) {
17658	const ValueDecl *Decl = DeclRef->getDecl();
17659	Diag(Loc: E->getExprLoc(), DiagID: diag::warn_dereference_of_noderef_type)
17660	<< Decl->getName() << E->getSourceRange();
17661	Diag(Loc: Decl->getLocation(), DiagID: diag::note_previous_decl) << Decl->getName();
17662	} else {
17663	Diag(Loc: E->getExprLoc(), DiagID: diag::warn_dereference_of_noderef_type_no_decl)
17664	<< E->getSourceRange();
17665	}
17666	}
17667	Rec.PossibleDerefs.clear();
17668	}
17669
17670	void Sema::CheckUnusedVolatileAssignment(Expr *E) {
17671	if (!E->getType().isVolatileQualified() || !getLangOpts().CPlusPlus20)
17672	return;
17673
17674	// Note: ignoring parens here is not justified by the standard rules, but
17675	// ignoring parentheses seems like a more reasonable approach, and this only
17676	// drives a deprecation warning so doesn't affect conformance.
17677	if (auto *BO = dyn_cast<BinaryOperator>(Val: E->IgnoreParenImpCasts())) {
17678	if (BO->getOpcode() == BO_Assign) {
17679	auto &LHSs = ExprEvalContexts.back().VolatileAssignmentLHSs;
17680	llvm::erase(C&: LHSs, V: BO->getLHS());
17681	}
17682	}
17683	}
17684
17685	void Sema::MarkExpressionAsImmediateEscalating(Expr *E) {
17686	assert(getLangOpts().CPlusPlus20 &&
17687	ExprEvalContexts.back().InImmediateEscalatingFunctionContext &&
17688	"Cannot mark an immediate escalating expression outside of an "
17689	"immediate escalating context");
17690	if (auto *Call = dyn_cast<CallExpr>(Val: E->IgnoreImplicit());
17691	Call && Call->getCallee()) {
17692	if (auto *DeclRef =
17693	dyn_cast<DeclRefExpr>(Val: Call->getCallee()->IgnoreImplicit()))
17694	DeclRef->setIsImmediateEscalating(true);
17695	} else if (auto *Ctr = dyn_cast<CXXConstructExpr>(Val: E->IgnoreImplicit())) {
17696	Ctr->setIsImmediateEscalating(true);
17697	} else if (auto *DeclRef = dyn_cast<DeclRefExpr>(Val: E->IgnoreImplicit())) {
17698	DeclRef->setIsImmediateEscalating(true);
17699	} else {
17700	assert(false && "expected an immediately escalating expression");
17701	}
17702	if (FunctionScopeInfo *FI = getCurFunction())
17703	FI->FoundImmediateEscalatingExpression = true;
17704	}
17705
17706	ExprResult Sema::CheckForImmediateInvocation(ExprResult E, FunctionDecl *Decl) {
17707	if (isUnevaluatedContext() || !E.isUsable() || !Decl ||
17708	!Decl->isImmediateFunction() || isAlwaysConstantEvaluatedContext() ||
17709	isCheckingDefaultArgumentOrInitializer() ||
17710	RebuildingImmediateInvocation || isImmediateFunctionContext())
17711	return E;
17712
17713	/// Opportunistically remove the callee from ReferencesToConsteval if we can.
17714	/// It's OK if this fails; we'll also remove this in
17715	/// HandleImmediateInvocations, but catching it here allows us to avoid
17716	/// walking the AST looking for it in simple cases.
17717	if (auto *Call = dyn_cast<CallExpr>(Val: E.get()->IgnoreImplicit()))
17718	if (auto *DeclRef =
17719	dyn_cast<DeclRefExpr>(Val: Call->getCallee()->IgnoreImplicit()))
17720	ExprEvalContexts.back().ReferenceToConsteval.erase(Ptr: DeclRef);
17721
17722	// C++23 [expr.const]/p16
17723	// An expression or conversion is immediate-escalating if it is not initially
17724	// in an immediate function context and it is [...] an immediate invocation
17725	// that is not a constant expression and is not a subexpression of an
17726	// immediate invocation.
17727	APValue Cached;
17728	auto CheckConstantExpressionAndKeepResult = [&]() {
17729	llvm::SmallVector<PartialDiagnosticAt, 8> Notes;
17730	Expr::EvalResult Eval;
17731	Eval.Diag = &Notes;
17732	bool Res = E.get()->EvaluateAsConstantExpr(
17733	Result&: Eval, Ctx: getASTContext(), Kind: ConstantExprKind::ImmediateInvocation);
17734	if (Res && Notes.empty()) {
17735	Cached = std::move(Eval.Val);
17736	return true;
17737	}
17738	return false;
17739	};
17740
17741	if (!E.get()->isValueDependent() &&
17742	ExprEvalContexts.back().InImmediateEscalatingFunctionContext &&
17743	!CheckConstantExpressionAndKeepResult()) {
17744	MarkExpressionAsImmediateEscalating(E: E.get());
17745	return E;
17746	}
17747
17748	if (Cleanup.exprNeedsCleanups()) {
17749	// Since an immediate invocation is a full expression itself - it requires
17750	// an additional ExprWithCleanups node, but it can participate to a bigger
17751	// full expression which actually requires cleanups to be run after so
17752	// create ExprWithCleanups without using MaybeCreateExprWithCleanups as it
17753	// may discard cleanups for outer expression too early.
17754
17755	// Note that ExprWithCleanups created here must always have empty cleanup
17756	// objects:
17757	// - compound literals do not create cleanup objects in C++ and immediate
17758	// invocations are C++-only.
17759	// - blocks are not allowed inside constant expressions and compiler will
17760	// issue an error if they appear there.
17761	//
17762	// Hence, in correct code any cleanup objects created inside current
17763	// evaluation context must be outside the immediate invocation.
17764	E = ExprWithCleanups::Create(C: getASTContext(), subexpr: E.get(),
17765	CleanupsHaveSideEffects: Cleanup.cleanupsHaveSideEffects(), objects: {});
17766	}
17767
17768	ConstantExpr *Res = ConstantExpr::Create(
17769	Context: getASTContext(), E: E.get(),
17770	Storage: ConstantExpr::getStorageKind(T: Decl->getReturnType().getTypePtr(),
17771	Context: getASTContext()),
17772	/*IsImmediateInvocation*/ true);
17773	if (Cached.hasValue())
17774	Res->MoveIntoResult(Value&: Cached, Context: getASTContext());
17775	/// Value-dependent constant expressions should not be immediately
17776	/// evaluated until they are instantiated.
17777	if (!Res->isValueDependent())
17778	ExprEvalContexts.back().ImmediateInvocationCandidates.emplace_back(Args&: Res, Args: 0);
17779	return Res;
17780	}
17781
17782	static void EvaluateAndDiagnoseImmediateInvocation(
17783	Sema &SemaRef, Sema::ImmediateInvocationCandidate Candidate) {
17784	llvm::SmallVector<PartialDiagnosticAt, 8> Notes;
17785	Expr::EvalResult Eval;
17786	Eval.Diag = &Notes;
17787	ConstantExpr *CE = Candidate.getPointer();
17788	bool Result = CE->EvaluateAsConstantExpr(
17789	Result&: Eval, Ctx: SemaRef.getASTContext(), Kind: ConstantExprKind::ImmediateInvocation);
17790	if (!Result || !Notes.empty()) {
17791	SemaRef.FailedImmediateInvocations.insert(Ptr: CE);
17792	Expr *InnerExpr = CE->getSubExpr()->IgnoreImplicit();
17793	if (auto *FunctionalCast = dyn_cast<CXXFunctionalCastExpr>(Val: InnerExpr))
17794	InnerExpr = FunctionalCast->getSubExpr()->IgnoreImplicit();
17795	FunctionDecl *FD = nullptr;
17796	if (auto *Call = dyn_cast<CallExpr>(Val: InnerExpr))
17797	FD = cast<FunctionDecl>(Val: Call->getCalleeDecl());
17798	else if (auto *Call = dyn_cast<CXXConstructExpr>(Val: InnerExpr))
17799	FD = Call->getConstructor();
17800	else if (auto *Cast = dyn_cast<CastExpr>(Val: InnerExpr))
17801	FD = dyn_cast_or_null<FunctionDecl>(Val: Cast->getConversionFunction());
17802
17803	assert(FD && FD->isImmediateFunction() &&
17804	"could not find an immediate function in this expression");
17805	if (FD->isInvalidDecl())
17806	return;
17807	SemaRef.Diag(Loc: CE->getBeginLoc(), DiagID: diag::err_invalid_consteval_call)
17808	<< FD << FD->isConsteval();
17809	if (auto Context =
17810	SemaRef.InnermostDeclarationWithDelayedImmediateInvocations()) {
17811	SemaRef.Diag(Loc: Context->Loc, DiagID: diag::note_invalid_consteval_initializer)
17812	<< Context->Decl;
17813	SemaRef.Diag(Loc: Context->Decl->getBeginLoc(), DiagID: diag::note_declared_at);
17814	}
17815	if (!FD->isConsteval())
17816	SemaRef.DiagnoseImmediateEscalatingReason(FD);
17817	for (auto &Note : Notes)
17818	SemaRef.Diag(Loc: Note.first, PD: Note.second);
17819	return;
17820	}
17821	CE->MoveIntoResult(Value&: Eval.Val, Context: SemaRef.getASTContext());
17822	}
17823
17824	static void RemoveNestedImmediateInvocation(
17825	Sema &SemaRef, Sema::ExpressionEvaluationContextRecord &Rec,
17826	SmallVector<Sema::ImmediateInvocationCandidate, 4>::reverse_iterator It) {
17827	struct ComplexRemove : TreeTransform<ComplexRemove> {
17828	using Base = TreeTransform<ComplexRemove>;
17829	llvm::SmallPtrSetImpl<DeclRefExpr *> &DRSet;
17830	SmallVector<Sema::ImmediateInvocationCandidate, 4> &IISet;
17831	SmallVector<Sema::ImmediateInvocationCandidate, 4>::reverse_iterator
17832	CurrentII;
17833	ComplexRemove(Sema &SemaRef, llvm::SmallPtrSetImpl<DeclRefExpr *> &DR,
17834	SmallVector<Sema::ImmediateInvocationCandidate, 4> &II,
17835	SmallVector<Sema::ImmediateInvocationCandidate,
17836	4>::reverse_iterator Current)
17837	: Base(SemaRef), DRSet(DR), IISet(II), CurrentII(Current) {}
17838	void RemoveImmediateInvocation(ConstantExpr* E) {
17839	auto It = std::find_if(first: CurrentII, last: IISet.rend(),
17840	pred: [E](Sema::ImmediateInvocationCandidate Elem) {
17841	return Elem.getPointer() == E;
17842	});
17843	// It is possible that some subexpression of the current immediate
17844	// invocation was handled from another expression evaluation context. Do
17845	// not handle the current immediate invocation if some of its
17846	// subexpressions failed before.
17847	if (It == IISet.rend()) {
17848	if (SemaRef.FailedImmediateInvocations.contains(Ptr: E))
17849	CurrentII->setInt(1);
17850	} else {
17851	It->setInt(1); // Mark as deleted
17852	}
17853	}
17854	ExprResult TransformConstantExpr(ConstantExpr *E) {
17855	if (!E->isImmediateInvocation())
17856	return Base::TransformConstantExpr(E);
17857	RemoveImmediateInvocation(E);
17858	return Base::TransformExpr(E: E->getSubExpr());
17859	}
17860	/// Base::TransfromCXXOperatorCallExpr doesn't traverse the callee so
17861	/// we need to remove its DeclRefExpr from the DRSet.
17862	ExprResult TransformCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
17863	DRSet.erase(Ptr: cast<DeclRefExpr>(Val: E->getCallee()->IgnoreImplicit()));
17864	return Base::TransformCXXOperatorCallExpr(E);
17865	}
17866	/// Base::TransformUserDefinedLiteral doesn't preserve the
17867	/// UserDefinedLiteral node.
17868	ExprResult TransformUserDefinedLiteral(UserDefinedLiteral *E) { return E; }
17869	/// Base::TransformInitializer skips ConstantExpr so we need to visit them
17870	/// here.
17871	ExprResult TransformInitializer(Expr *Init, bool NotCopyInit) {
17872	if (!Init)
17873	return Init;
17874
17875	// We cannot use IgnoreImpCasts because we need to preserve
17876	// full expressions.
17877	while (true) {
17878	if (auto *ICE = dyn_cast<ImplicitCastExpr>(Val: Init))
17879	Init = ICE->getSubExpr();
17880	else if (auto *ICE = dyn_cast<MaterializeTemporaryExpr>(Val: Init))
17881	Init = ICE->getSubExpr();
17882	else
17883	break;
17884	}
17885	/// ConstantExprs are the first layer of implicit node to be removed so if
17886	/// Init isn't a ConstantExpr, no ConstantExpr will be skipped.
17887	if (auto *CE = dyn_cast<ConstantExpr>(Val: Init);
17888	CE && CE->isImmediateInvocation())
17889	RemoveImmediateInvocation(E: CE);
17890	return Base::TransformInitializer(Init, NotCopyInit);
17891	}
17892	ExprResult TransformDeclRefExpr(DeclRefExpr *E) {
17893	DRSet.erase(Ptr: E);
17894	return E;
17895	}
17896	ExprResult TransformLambdaExpr(LambdaExpr *E) {
17897	// Do not rebuild lambdas to avoid creating a new type.
17898	// Lambdas have already been processed inside their eval contexts.
17899	return E;
17900	}
17901	bool AlwaysRebuild() { return false; }
17902	bool ReplacingOriginal() { return true; }
17903	bool AllowSkippingCXXConstructExpr() {
17904	bool Res = AllowSkippingFirstCXXConstructExpr;
17905	AllowSkippingFirstCXXConstructExpr = true;
17906	return Res;
17907	}
17908	bool AllowSkippingFirstCXXConstructExpr = true;
17909	} Transformer(SemaRef, Rec.ReferenceToConsteval,
17910	Rec.ImmediateInvocationCandidates, It);
17911
17912	/// CXXConstructExpr with a single argument are getting skipped by
17913	/// TreeTransform in some situtation because they could be implicit. This
17914	/// can only occur for the top-level CXXConstructExpr because it is used
17915	/// nowhere in the expression being transformed therefore will not be rebuilt.
17916	/// Setting AllowSkippingFirstCXXConstructExpr to false will prevent from
17917	/// skipping the first CXXConstructExpr.
17918	if (isa<CXXConstructExpr>(Val: It->getPointer()->IgnoreImplicit()))
17919	Transformer.AllowSkippingFirstCXXConstructExpr = false;
17920
17921	ExprResult Res = Transformer.TransformExpr(E: It->getPointer()->getSubExpr());
17922	// The result may not be usable in case of previous compilation errors.
17923	// In this case evaluation of the expression may result in crash so just
17924	// don't do anything further with the result.
17925	if (Res.isUsable()) {
17926	Res = SemaRef.MaybeCreateExprWithCleanups(SubExpr: Res);
17927	It->getPointer()->setSubExpr(Res.get());
17928	}
17929	}
17930
17931	static void
17932	HandleImmediateInvocations(Sema &SemaRef,
17933	Sema::ExpressionEvaluationContextRecord &Rec) {
17934	if ((Rec.ImmediateInvocationCandidates.size() == 0 &&
17935	Rec.ReferenceToConsteval.size() == 0) ||
17936	Rec.isImmediateFunctionContext() || SemaRef.RebuildingImmediateInvocation)
17937	return;
17938
17939	// An expression or conversion is 'manifestly constant-evaluated' if it is:
17940	// [...]
17941	// - the initializer of a variable that is usable in constant expressions or
17942	// has constant initialization.
17943	if (SemaRef.getLangOpts().CPlusPlus23 &&
17944	Rec.ExprContext ==
17945	Sema::ExpressionEvaluationContextRecord::EK_VariableInit) {
17946	auto *VD = cast<VarDecl>(Val: Rec.ManglingContextDecl);
17947	if (VD->isUsableInConstantExpressions(C: SemaRef.Context) ||
17948	VD->hasConstantInitialization()) {
17949	// An expression or conversion is in an 'immediate function context' if it
17950	// is potentially evaluated and either:
17951	// [...]
17952	// - it is a subexpression of a manifestly constant-evaluated expression
17953	// or conversion.
17954	return;
17955	}
17956	}
17957
17958	/// When we have more than 1 ImmediateInvocationCandidates or previously
17959	/// failed immediate invocations, we need to check for nested
17960	/// ImmediateInvocationCandidates in order to avoid duplicate diagnostics.
17961	/// Otherwise we only need to remove ReferenceToConsteval in the immediate
17962	/// invocation.
17963	if (Rec.ImmediateInvocationCandidates.size() > 1 ||
17964	!SemaRef.FailedImmediateInvocations.empty()) {
17965
17966	/// Prevent sema calls during the tree transform from adding pointers that
17967	/// are already in the sets.
17968	llvm::SaveAndRestore DisableIITracking(
17969	SemaRef.RebuildingImmediateInvocation, true);
17970
17971	/// Prevent diagnostic during tree transfrom as they are duplicates
17972	Sema::TentativeAnalysisScope DisableDiag(SemaRef);
17973
17974	for (auto It = Rec.ImmediateInvocationCandidates.rbegin();
17975	It != Rec.ImmediateInvocationCandidates.rend(); It++)
17976	if (!It->getInt())
17977	RemoveNestedImmediateInvocation(SemaRef, Rec, It);
17978	} else if (Rec.ImmediateInvocationCandidates.size() == 1 &&
17979	Rec.ReferenceToConsteval.size()) {
17980	struct SimpleRemove : DynamicRecursiveASTVisitor {
17981	llvm::SmallPtrSetImpl<DeclRefExpr *> &DRSet;
17982	SimpleRemove(llvm::SmallPtrSetImpl<DeclRefExpr *> &S) : DRSet(S) {}
17983	bool VisitDeclRefExpr(DeclRefExpr *E) override {
17984	DRSet.erase(Ptr: E);
17985	return DRSet.size();
17986	}
17987	} Visitor(Rec.ReferenceToConsteval);
17988	Visitor.TraverseStmt(
17989	S: Rec.ImmediateInvocationCandidates.front().getPointer()->getSubExpr());
17990	}
17991	for (auto CE : Rec.ImmediateInvocationCandidates)
17992	if (!CE.getInt())
17993	EvaluateAndDiagnoseImmediateInvocation(SemaRef, Candidate: CE);
17994	for (auto *DR : Rec.ReferenceToConsteval) {
17995	// If the expression is immediate escalating, it is not an error;
17996	// The outer context itself becomes immediate and further errors,
17997	// if any, will be handled by DiagnoseImmediateEscalatingReason.
17998	if (DR->isImmediateEscalating())
17999	continue;
18000	auto *FD = cast<FunctionDecl>(Val: DR->getDecl());
18001	const NamedDecl *ND = FD;
18002	if (const auto *MD = dyn_cast<CXXMethodDecl>(Val: ND);
18003	MD && (MD->isLambdaStaticInvoker() || isLambdaCallOperator(MD)))
18004	ND = MD->getParent();
18005
18006	// C++23 [expr.const]/p16
18007	// An expression or conversion is immediate-escalating if it is not
18008	// initially in an immediate function context and it is [...] a
18009	// potentially-evaluated id-expression that denotes an immediate function
18010	// that is not a subexpression of an immediate invocation.
18011	bool ImmediateEscalating = false;
18012	bool IsPotentiallyEvaluated =
18013	Rec.Context ==
18014	Sema::ExpressionEvaluationContext::PotentiallyEvaluated ||
18015	Rec.Context ==
18016	Sema::ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed;
18017	if (SemaRef.inTemplateInstantiation() && IsPotentiallyEvaluated)
18018	ImmediateEscalating = Rec.InImmediateEscalatingFunctionContext;
18019
18020	if (!Rec.InImmediateEscalatingFunctionContext ||
18021	(SemaRef.inTemplateInstantiation() && !ImmediateEscalating)) {
18022	SemaRef.Diag(Loc: DR->getBeginLoc(), DiagID: diag::err_invalid_consteval_take_address)
18023	<< ND << isa<CXXRecordDecl>(Val: ND) << FD->isConsteval();
18024	if (!FD->getBuiltinID())
18025	SemaRef.Diag(Loc: ND->getLocation(), DiagID: diag::note_declared_at);
18026	if (auto Context =
18027	SemaRef.InnermostDeclarationWithDelayedImmediateInvocations()) {
18028	SemaRef.Diag(Loc: Context->Loc, DiagID: diag::note_invalid_consteval_initializer)
18029	<< Context->Decl;
18030	SemaRef.Diag(Loc: Context->Decl->getBeginLoc(), DiagID: diag::note_declared_at);
18031	}
18032	if (FD->isImmediateEscalating() && !FD->isConsteval())
18033	SemaRef.DiagnoseImmediateEscalatingReason(FD);
18034
18035	} else {
18036	SemaRef.MarkExpressionAsImmediateEscalating(E: DR);
18037	}
18038	}
18039	}
18040
18041	void Sema::PopExpressionEvaluationContext() {
18042	ExpressionEvaluationContextRecord& Rec = ExprEvalContexts.back();
18043	if (!Rec.Lambdas.empty()) {
18044	using ExpressionKind = ExpressionEvaluationContextRecord::ExpressionKind;
18045	if (!getLangOpts().CPlusPlus20 &&
18046	(Rec.ExprContext == ExpressionKind::EK_TemplateArgument ||
18047	Rec.isUnevaluated() ||
18048	(Rec.isConstantEvaluated() && !getLangOpts().CPlusPlus17))) {
18049	unsigned D;
18050	if (Rec.isUnevaluated()) {
18051	// C++11 [expr.prim.lambda]p2:
18052	// A lambda-expression shall not appear in an unevaluated operand
18053	// (Clause 5).
18054	D = diag::err_lambda_unevaluated_operand;
18055	} else if (Rec.isConstantEvaluated() && !getLangOpts().CPlusPlus17) {
18056	// C++1y [expr.const]p2:
18057	// A conditional-expression e is a core constant expression unless the
18058	// evaluation of e, following the rules of the abstract machine, would
18059	// evaluate [...] a lambda-expression.
18060	D = diag::err_lambda_in_constant_expression;
18061	} else if (Rec.ExprContext == ExpressionKind::EK_TemplateArgument) {
18062	// C++17 [expr.prim.lamda]p2:
18063	// A lambda-expression shall not appear [...] in a template-argument.
18064	D = diag::err_lambda_in_invalid_context;
18065	} else
18066	llvm_unreachable("Couldn't infer lambda error message.");
18067
18068	for (const auto *L : Rec.Lambdas)
18069	Diag(Loc: L->getBeginLoc(), DiagID: D);
18070	}
18071	}
18072
18073	// Append the collected materialized temporaries into previous context before
18074	// exit if the previous also is a lifetime extending context.
18075	if (getLangOpts().CPlusPlus23 && Rec.InLifetimeExtendingContext &&
18076	parentEvaluationContext().InLifetimeExtendingContext &&
18077	!Rec.ForRangeLifetimeExtendTemps.empty()) {
18078	parentEvaluationContext().ForRangeLifetimeExtendTemps.append(
18079	RHS: Rec.ForRangeLifetimeExtendTemps);
18080	}
18081
18082	WarnOnPendingNoDerefs(Rec);
18083	HandleImmediateInvocations(SemaRef&: *this, Rec);
18084
18085	// Warn on any volatile-qualified simple-assignments that are not discarded-
18086	// value expressions nor unevaluated operands (those cases get removed from
18087	// this list by CheckUnusedVolatileAssignment).
18088	for (auto *BO : Rec.VolatileAssignmentLHSs)
18089	Diag(Loc: BO->getBeginLoc(), DiagID: diag::warn_deprecated_simple_assign_volatile)
18090	<< BO->getType();
18091
18092	// When are coming out of an unevaluated context, clear out any
18093	// temporaries that we may have created as part of the evaluation of
18094	// the expression in that context: they aren't relevant because they
18095	// will never be constructed.
18096	if (Rec.isUnevaluated() || Rec.isConstantEvaluated()) {
18097	ExprCleanupObjects.erase(CS: ExprCleanupObjects.begin() + Rec.NumCleanupObjects,
18098	CE: ExprCleanupObjects.end());
18099	Cleanup = Rec.ParentCleanup;
18100	CleanupVarDeclMarking();
18101	std::swap(LHS&: MaybeODRUseExprs, RHS&: Rec.SavedMaybeODRUseExprs);
18102	// Otherwise, merge the contexts together.
18103	} else {
18104	Cleanup.mergeFrom(Rhs: Rec.ParentCleanup);
18105	MaybeODRUseExprs.insert_range(R&: Rec.SavedMaybeODRUseExprs);
18106	}
18107
18108	// Pop the current expression evaluation context off the stack.
18109	ExprEvalContexts.pop_back();
18110	}
18111
18112	void Sema::DiscardCleanupsInEvaluationContext() {
18113	ExprCleanupObjects.erase(
18114	CS: ExprCleanupObjects.begin() + ExprEvalContexts.back().NumCleanupObjects,
18115	CE: ExprCleanupObjects.end());
18116	Cleanup.reset();
18117	MaybeODRUseExprs.clear();
18118	}
18119
18120	ExprResult Sema::HandleExprEvaluationContextForTypeof(Expr *E) {
18121	ExprResult Result = CheckPlaceholderExpr(E);
18122	if (Result.isInvalid())
18123	return ExprError();
18124	E = Result.get();
18125	if (!E->getType()->isVariablyModifiedType())
18126	return E;
18127	return TransformToPotentiallyEvaluated(E);
18128	}
18129
18130	/// Are we in a context that is potentially constant evaluated per C++20
18131	/// [expr.const]p12?
18132	static bool isPotentiallyConstantEvaluatedContext(Sema &SemaRef) {
18133	/// C++2a [expr.const]p12:
18134	// An expression or conversion is potentially constant evaluated if it is
18135	switch (SemaRef.ExprEvalContexts.back().Context) {
18136	case Sema::ExpressionEvaluationContext::ConstantEvaluated:
18137	case Sema::ExpressionEvaluationContext::ImmediateFunctionContext:
18138
18139	// -- a manifestly constant-evaluated expression,
18140	case Sema::ExpressionEvaluationContext::PotentiallyEvaluated:
18141	case Sema::ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
18142	case Sema::ExpressionEvaluationContext::DiscardedStatement:
18143	// -- a potentially-evaluated expression,
18144	case Sema::ExpressionEvaluationContext::UnevaluatedList:
18145	// -- an immediate subexpression of a braced-init-list,
18146
18147	// -- [FIXME] an expression of the form & cast-expression that occurs
18148	// within a templated entity
18149	// -- a subexpression of one of the above that is not a subexpression of
18150	// a nested unevaluated operand.
18151	return true;
18152
18153	case Sema::ExpressionEvaluationContext::Unevaluated:
18154	case Sema::ExpressionEvaluationContext::UnevaluatedAbstract:
18155	// Expressions in this context are never evaluated.
18156	return false;
18157	}
18158	llvm_unreachable("Invalid context");
18159	}
18160
18161	/// Return true if this function has a calling convention that requires mangling
18162	/// in the size of the parameter pack.
18163	static bool funcHasParameterSizeMangling(Sema &S, FunctionDecl *FD) {
18164	// These manglings are only applicable for targets whcih use Microsoft
18165	// mangling scheme for C.
18166	if (!S.Context.getTargetInfo().shouldUseMicrosoftCCforMangling())
18167	return false;
18168
18169	// If this is C++ and this isn't an extern "C" function, parameters do not
18170	// need to be complete. In this case, C++ mangling will apply, which doesn't
18171	// use the size of the parameters.
18172	if (S.getLangOpts().CPlusPlus && !FD->isExternC())
18173	return false;
18174
18175	// Stdcall, fastcall, and vectorcall need this special treatment.
18176	CallingConv CC = FD->getType()->castAs<FunctionType>()->getCallConv();
18177	switch (CC) {
18178	case CC_X86StdCall:
18179	case CC_X86FastCall:
18180	case CC_X86VectorCall:
18181	return true;
18182	default:
18183	break;
18184	}
18185	return false;
18186	}
18187
18188	/// Require that all of the parameter types of function be complete. Normally,
18189	/// parameter types are only required to be complete when a function is called
18190	/// or defined, but to mangle functions with certain calling conventions, the
18191	/// mangler needs to know the size of the parameter list. In this situation,
18192	/// MSVC doesn't emit an error or instantiate templates. Instead, MSVC mangles
18193	/// the function as _foo@0, i.e. zero bytes of parameters, which will usually
18194	/// result in a linker error. Clang doesn't implement this behavior, and instead
18195	/// attempts to error at compile time.
18196	static void CheckCompleteParameterTypesForMangler(Sema &S, FunctionDecl *FD,
18197	SourceLocation Loc) {
18198	class ParamIncompleteTypeDiagnoser : public Sema::TypeDiagnoser {
18199	FunctionDecl *FD;
18200	ParmVarDecl *Param;
18201
18202	public:
18203	ParamIncompleteTypeDiagnoser(FunctionDecl *FD, ParmVarDecl *Param)
18204	: FD(FD), Param(Param) {}
18205
18206	void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
18207	CallingConv CC = FD->getType()->castAs<FunctionType>()->getCallConv();
18208	StringRef CCName;
18209	switch (CC) {
18210	case CC_X86StdCall:
18211	CCName = "stdcall";
18212	break;
18213	case CC_X86FastCall:
18214	CCName = "fastcall";
18215	break;
18216	case CC_X86VectorCall:
18217	CCName = "vectorcall";
18218	break;
18219	default:
18220	llvm_unreachable("CC does not need mangling");
18221	}
18222
18223	S.Diag(Loc, DiagID: diag::err_cconv_incomplete_param_type)
18224	<< Param->getDeclName() << FD->getDeclName() << CCName;
18225	}
18226	};
18227
18228	for (ParmVarDecl *Param : FD->parameters()) {
18229	ParamIncompleteTypeDiagnoser Diagnoser(FD, Param);
18230	S.RequireCompleteType(Loc, T: Param->getType(), Diagnoser);
18231	}
18232	}
18233
18234	namespace {
18235	enum class OdrUseContext {
18236	/// Declarations in this context are not odr-used.
18237	None,
18238	/// Declarations in this context are formally odr-used, but this is a
18239	/// dependent context.
18240	Dependent,
18241	/// Declarations in this context are odr-used but not actually used (yet).
18242	FormallyOdrUsed,
18243	/// Declarations in this context are used.
18244	Used
18245	};
18246	}
18247
18248	/// Are we within a context in which references to resolved functions or to
18249	/// variables result in odr-use?
18250	static OdrUseContext isOdrUseContext(Sema &SemaRef) {
18251	const Sema::ExpressionEvaluationContextRecord &Context =
18252	SemaRef.currentEvaluationContext();
18253
18254	if (Context.isUnevaluated())
18255	return OdrUseContext::None;
18256
18257	if (SemaRef.CurContext->isDependentContext())
18258	return OdrUseContext::Dependent;
18259
18260	if (Context.isDiscardedStatementContext())
18261	return OdrUseContext::FormallyOdrUsed;
18262
18263	else if (Context.Context ==
18264	Sema::ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed)
18265	return OdrUseContext::FormallyOdrUsed;
18266
18267	return OdrUseContext::Used;
18268	}
18269
18270	static bool isImplicitlyDefinableConstexprFunction(FunctionDecl *Func) {
18271	if (!Func->isConstexpr())
18272	return false;
18273
18274	if (Func->isImplicitlyInstantiable() || !Func->isUserProvided())
18275	return true;
18276
18277	// Lambda conversion operators are never user provided.
18278	if (CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(Val: Func))
18279	return isLambdaConversionOperator(C: Conv);
18280
18281	auto *CCD = dyn_cast<CXXConstructorDecl>(Val: Func);
18282	return CCD && CCD->getInheritedConstructor();
18283	}
18284
18285	void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func,
18286	bool MightBeOdrUse) {
18287	assert(Func && "No function?");
18288
18289	Func->setReferenced();
18290
18291	// Recursive functions aren't really used until they're used from some other
18292	// context.
18293	bool IsRecursiveCall = CurContext == Func;
18294
18295	// C++11 [basic.def.odr]p3:
18296	// A function whose name appears as a potentially-evaluated expression is
18297	// odr-used if it is the unique lookup result or the selected member of a
18298	// set of overloaded functions [...].
18299	//
18300	// We (incorrectly) mark overload resolution as an unevaluated context, so we
18301	// can just check that here.
18302	OdrUseContext OdrUse =
18303	MightBeOdrUse ? isOdrUseContext(SemaRef&: *this) : OdrUseContext::None;
18304	if (IsRecursiveCall && OdrUse == OdrUseContext::Used)
18305	OdrUse = OdrUseContext::FormallyOdrUsed;
18306
18307	// Trivial default constructors and destructors are never actually used.
18308	// FIXME: What about other special members?
18309	if (Func->isTrivial() && !Func->hasAttr<DLLExportAttr>() &&
18310	OdrUse == OdrUseContext::Used) {
18311	if (auto *Constructor = dyn_cast<CXXConstructorDecl>(Val: Func))
18312	if (Constructor->isDefaultConstructor())
18313	OdrUse = OdrUseContext::FormallyOdrUsed;
18314	if (isa<CXXDestructorDecl>(Val: Func))
18315	OdrUse = OdrUseContext::FormallyOdrUsed;
18316	}
18317
18318	// C++20 [expr.const]p12:
18319	// A function [...] is needed for constant evaluation if it is [...] a
18320	// constexpr function that is named by an expression that is potentially
18321	// constant evaluated
18322	bool NeededForConstantEvaluation =
18323	isPotentiallyConstantEvaluatedContext(SemaRef&: *this) &&
18324	isImplicitlyDefinableConstexprFunction(Func);
18325
18326	// Determine whether we require a function definition to exist, per
18327	// C++11 [temp.inst]p3:
18328	// Unless a function template specialization has been explicitly
18329	// instantiated or explicitly specialized, the function template
18330	// specialization is implicitly instantiated when the specialization is
18331	// referenced in a context that requires a function definition to exist.
18332	// C++20 [temp.inst]p7:
18333	// The existence of a definition of a [...] function is considered to
18334	// affect the semantics of the program if the [...] function is needed for
18335	// constant evaluation by an expression
18336	// C++20 [basic.def.odr]p10:
18337	// Every program shall contain exactly one definition of every non-inline
18338	// function or variable that is odr-used in that program outside of a
18339	// discarded statement
18340	// C++20 [special]p1:
18341	// The implementation will implicitly define [defaulted special members]
18342	// if they are odr-used or needed for constant evaluation.
18343	//
18344	// Note that we skip the implicit instantiation of templates that are only
18345	// used in unused default arguments or by recursive calls to themselves.
18346	// This is formally non-conforming, but seems reasonable in practice.
18347	bool NeedDefinition =
18348	!IsRecursiveCall &&
18349	(OdrUse == OdrUseContext::Used ||
18350	(NeededForConstantEvaluation && !Func->isPureVirtual()));
18351
18352	// C++14 [temp.expl.spec]p6:
18353	// If a template [...] is explicitly specialized then that specialization
18354	// shall be declared before the first use of that specialization that would
18355	// cause an implicit instantiation to take place, in every translation unit
18356	// in which such a use occurs
18357	if (NeedDefinition &&
18358	(Func->getTemplateSpecializationKind() != TSK_Undeclared ||
18359	Func->getMemberSpecializationInfo()))
18360	checkSpecializationReachability(Loc, Spec: Func);
18361
18362	if (getLangOpts().CUDA)
18363	CUDA().CheckCall(Loc, Callee: Func);
18364
18365	// If we need a definition, try to create one.
18366	if (NeedDefinition && !Func->getBody()) {
18367	runWithSufficientStackSpace(Loc, Fn: [&] {
18368	if (CXXConstructorDecl *Constructor =
18369	dyn_cast<CXXConstructorDecl>(Val: Func)) {
18370	Constructor = cast<CXXConstructorDecl>(Val: Constructor->getFirstDecl());
18371	if (Constructor->isDefaulted() && !Constructor->isDeleted()) {
18372	if (Constructor->isDefaultConstructor()) {
18373	if (Constructor->isTrivial() &&
18374	!Constructor->hasAttr<DLLExportAttr>())
18375	return;
18376	DefineImplicitDefaultConstructor(CurrentLocation: Loc, Constructor);
18377	} else if (Constructor->isCopyConstructor()) {
18378	DefineImplicitCopyConstructor(CurrentLocation: Loc, Constructor);
18379	} else if (Constructor->isMoveConstructor()) {
18380	DefineImplicitMoveConstructor(CurrentLocation: Loc, Constructor);
18381	}
18382	} else if (Constructor->getInheritedConstructor()) {
18383	DefineInheritingConstructor(UseLoc: Loc, Constructor);
18384	}
18385	} else if (CXXDestructorDecl *Destructor =
18386	dyn_cast<CXXDestructorDecl>(Val: Func)) {
18387	Destructor = cast<CXXDestructorDecl>(Val: Destructor->getFirstDecl());
18388	if (Destructor->isDefaulted() && !Destructor->isDeleted()) {
18389	if (Destructor->isTrivial() && !Destructor->hasAttr<DLLExportAttr>())
18390	return;
18391	DefineImplicitDestructor(CurrentLocation: Loc, Destructor);
18392	}
18393	if (Destructor->isVirtual() && getLangOpts().AppleKext)
18394	MarkVTableUsed(Loc, Class: Destructor->getParent());
18395	} else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(Val: Func)) {
18396	if (MethodDecl->isOverloadedOperator() &&
18397	MethodDecl->getOverloadedOperator() == OO_Equal) {
18398	MethodDecl = cast<CXXMethodDecl>(Val: MethodDecl->getFirstDecl());
18399	if (MethodDecl->isDefaulted() && !MethodDecl->isDeleted()) {
18400	if (MethodDecl->isCopyAssignmentOperator())
18401	DefineImplicitCopyAssignment(CurrentLocation: Loc, MethodDecl);
18402	else if (MethodDecl->isMoveAssignmentOperator())
18403	DefineImplicitMoveAssignment(CurrentLocation: Loc, MethodDecl);
18404	}
18405	} else if (isa<CXXConversionDecl>(Val: MethodDecl) &&
18406	MethodDecl->getParent()->isLambda()) {
18407	CXXConversionDecl *Conversion =
18408	cast<CXXConversionDecl>(Val: MethodDecl->getFirstDecl());
18409	if (Conversion->isLambdaToBlockPointerConversion())
18410	DefineImplicitLambdaToBlockPointerConversion(CurrentLoc: Loc, Conv: Conversion);
18411	else
18412	DefineImplicitLambdaToFunctionPointerConversion(CurrentLoc: Loc, Conv: Conversion);
18413	} else if (MethodDecl->isVirtual() && getLangOpts().AppleKext)
18414	MarkVTableUsed(Loc, Class: MethodDecl->getParent());
18415	}
18416
18417	if (Func->isDefaulted() && !Func->isDeleted()) {
18418	DefaultedComparisonKind DCK = getDefaultedComparisonKind(FD: Func);
18419	if (DCK != DefaultedComparisonKind::None)
18420	DefineDefaultedComparison(Loc, FD: Func, DCK);
18421	}
18422
18423	// Implicit instantiation of function templates and member functions of
18424	// class templates.
18425	if (Func->isImplicitlyInstantiable()) {
18426	TemplateSpecializationKind TSK =
18427	Func->getTemplateSpecializationKindForInstantiation();
18428	SourceLocation PointOfInstantiation = Func->getPointOfInstantiation();
18429	bool FirstInstantiation = PointOfInstantiation.isInvalid();
18430	if (FirstInstantiation) {
18431	PointOfInstantiation = Loc;
18432	if (auto *MSI = Func->getMemberSpecializationInfo())
18433	MSI->setPointOfInstantiation(Loc);
18434	// FIXME: Notify listener.
18435	else
18436	Func->setTemplateSpecializationKind(TSK, PointOfInstantiation);
18437	} else if (TSK != TSK_ImplicitInstantiation) {
18438	// Use the point of use as the point of instantiation, instead of the
18439	// point of explicit instantiation (which we track as the actual point
18440	// of instantiation). This gives better backtraces in diagnostics.
18441	PointOfInstantiation = Loc;
18442	}
18443
18444	if (FirstInstantiation || TSK != TSK_ImplicitInstantiation ||
18445	Func->isConstexpr()) {
18446	if (isa<CXXRecordDecl>(Val: Func->getDeclContext()) &&
18447	cast<CXXRecordDecl>(Val: Func->getDeclContext())->isLocalClass() &&
18448	CodeSynthesisContexts.size())
18449	PendingLocalImplicitInstantiations.push_back(
18450	x: std::make_pair(x&: Func, y&: PointOfInstantiation));
18451	else if (Func->isConstexpr())
18452	// Do not defer instantiations of constexpr functions, to avoid the
18453	// expression evaluator needing to call back into Sema if it sees a
18454	// call to such a function.
18455	InstantiateFunctionDefinition(PointOfInstantiation, Function: Func);
18456	else {
18457	Func->setInstantiationIsPending(true);
18458	PendingInstantiations.push_back(
18459	x: std::make_pair(x&: Func, y&: PointOfInstantiation));
18460	if (llvm::isTimeTraceVerbose()) {
18461	llvm::timeTraceAddInstantEvent(Name: "DeferInstantiation", Detail: [&] {
18462	std::string Name;
18463	llvm::raw_string_ostream OS(Name);
18464	Func->getNameForDiagnostic(OS, Policy: getPrintingPolicy(),
18465	/*Qualified=*/true);
18466	return Name;
18467	});
18468	}
18469	// Notify the consumer that a function was implicitly instantiated.
18470	Consumer.HandleCXXImplicitFunctionInstantiation(D: Func);
18471	}
18472	}
18473	} else {
18474	// Walk redefinitions, as some of them may be instantiable.
18475	for (auto *i : Func->redecls()) {
18476	if (!i->isUsed(CheckUsedAttr: false) && i->isImplicitlyInstantiable())
18477	MarkFunctionReferenced(Loc, Func: i, MightBeOdrUse);
18478	}
18479	}
18480	});
18481	}
18482
18483	// If a constructor was defined in the context of a default parameter
18484	// or of another default member initializer (ie a PotentiallyEvaluatedIfUsed
18485	// context), its initializers may not be referenced yet.
18486	if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Val: Func)) {
18487	EnterExpressionEvaluationContext EvalContext(
18488	*this,
18489	Constructor->isImmediateFunction()
18490	? ExpressionEvaluationContext::ImmediateFunctionContext
18491	: ExpressionEvaluationContext::PotentiallyEvaluated,
18492	Constructor);
18493	for (CXXCtorInitializer *Init : Constructor->inits()) {
18494	if (Init->isInClassMemberInitializer())
18495	runWithSufficientStackSpace(Loc: Init->getSourceLocation(), Fn: [&]() {
18496	MarkDeclarationsReferencedInExpr(E: Init->getInit());
18497	});
18498	}
18499	}
18500
18501	// C++14 [except.spec]p17:
18502	// An exception-specification is considered to be needed when:
18503	// - the function is odr-used or, if it appears in an unevaluated operand,
18504	// would be odr-used if the expression were potentially-evaluated;
18505	//
18506	// Note, we do this even if MightBeOdrUse is false. That indicates that the
18507	// function is a pure virtual function we're calling, and in that case the
18508	// function was selected by overload resolution and we need to resolve its
18509	// exception specification for a different reason.
18510	const FunctionProtoType *FPT = Func->getType()->getAs<FunctionProtoType>();
18511	if (FPT && isUnresolvedExceptionSpec(ESpecType: FPT->getExceptionSpecType()))
18512	ResolveExceptionSpec(Loc, FPT);
18513
18514	// A callee could be called by a host function then by a device function.
18515	// If we only try recording once, we will miss recording the use on device
18516	// side. Therefore keep trying until it is recorded.
18517	if (LangOpts.OffloadImplicitHostDeviceTemplates && LangOpts.CUDAIsDevice &&
18518	!getASTContext().CUDAImplicitHostDeviceFunUsedByDevice.count(V: Func))
18519	CUDA().RecordImplicitHostDeviceFuncUsedByDevice(FD: Func);
18520
18521	// If this is the first "real" use, act on that.
18522	if (OdrUse == OdrUseContext::Used && !Func->isUsed(/*CheckUsedAttr=*/false)) {
18523	// Keep track of used but undefined functions.
18524	if (!Func->isDefined() && !Func->isInAnotherModuleUnit()) {
18525	if (mightHaveNonExternalLinkage(FD: Func))
18526	UndefinedButUsed.insert(KV: std::make_pair(x: Func->getCanonicalDecl(), y&: Loc));
18527	else if (Func->getMostRecentDecl()->isInlined() &&
18528	!LangOpts.GNUInline &&
18529	!Func->getMostRecentDecl()->hasAttr<GNUInlineAttr>())
18530	UndefinedButUsed.insert(KV: std::make_pair(x: Func->getCanonicalDecl(), y&: Loc));
18531	else if (isExternalWithNoLinkageType(VD: Func))
18532	UndefinedButUsed.insert(KV: std::make_pair(x: Func->getCanonicalDecl(), y&: Loc));
18533	}
18534
18535	// Some x86 Windows calling conventions mangle the size of the parameter
18536	// pack into the name. Computing the size of the parameters requires the
18537	// parameter types to be complete. Check that now.
18538	if (funcHasParameterSizeMangling(S&: *this, FD: Func))
18539	CheckCompleteParameterTypesForMangler(S&: *this, FD: Func, Loc);
18540
18541	// In the MS C++ ABI, the compiler emits destructor variants where they are
18542	// used. If the destructor is used here but defined elsewhere, mark the
18543	// virtual base destructors referenced. If those virtual base destructors
18544	// are inline, this will ensure they are defined when emitting the complete
18545	// destructor variant. This checking may be redundant if the destructor is
18546	// provided later in this TU.
18547	if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
18548	if (auto *Dtor = dyn_cast<CXXDestructorDecl>(Val: Func)) {
18549	CXXRecordDecl *Parent = Dtor->getParent();
18550	if (Parent->getNumVBases() > 0 && !Dtor->getBody())
18551	CheckCompleteDestructorVariant(CurrentLocation: Loc, Dtor);
18552	}
18553	}
18554
18555	Func->markUsed(C&: Context);
18556	}
18557	}
18558
18559	/// Directly mark a variable odr-used. Given a choice, prefer to use
18560	/// MarkVariableReferenced since it does additional checks and then
18561	/// calls MarkVarDeclODRUsed.
18562	/// If the variable must be captured:
18563	/// - if FunctionScopeIndexToStopAt is null, capture it in the CurContext
18564	/// - else capture it in the DeclContext that maps to the
18565	/// *FunctionScopeIndexToStopAt on the FunctionScopeInfo stack.
18566	static void
18567	MarkVarDeclODRUsed(ValueDecl *V, SourceLocation Loc, Sema &SemaRef,
18568	const unsigned *const FunctionScopeIndexToStopAt = nullptr) {
18569	// Keep track of used but undefined variables.
18570	// FIXME: We shouldn't suppress this warning for static data members.
18571	VarDecl *Var = V->getPotentiallyDecomposedVarDecl();
18572	assert(Var && "expected a capturable variable");
18573
18574	if (Var->hasDefinition(SemaRef.Context) == VarDecl::DeclarationOnly &&
18575	(!Var->isExternallyVisible() || Var->isInline() ||
18576	SemaRef.isExternalWithNoLinkageType(VD: Var)) &&
18577	!(Var->isStaticDataMember() && Var->hasInit())) {
18578	SourceLocation &old = SemaRef.UndefinedButUsed[Var->getCanonicalDecl()];
18579	if (old.isInvalid())
18580	old = Loc;
18581	}
18582	QualType CaptureType, DeclRefType;
18583	if (SemaRef.LangOpts.OpenMP)
18584	SemaRef.OpenMP().tryCaptureOpenMPLambdas(V);
18585	SemaRef.tryCaptureVariable(Var: V, Loc, Kind: TryCaptureKind::Implicit,
18586	/*EllipsisLoc*/ SourceLocation(),
18587	/*BuildAndDiagnose*/ true, CaptureType,
18588	DeclRefType, FunctionScopeIndexToStopAt);
18589
18590	if (SemaRef.LangOpts.CUDA && Var->hasGlobalStorage()) {
18591	auto *FD = dyn_cast_or_null<FunctionDecl>(Val: SemaRef.CurContext);
18592	auto VarTarget = SemaRef.CUDA().IdentifyTarget(D: Var);
18593	auto UserTarget = SemaRef.CUDA().IdentifyTarget(D: FD);
18594	if (VarTarget == SemaCUDA::CVT_Host &&
18595	(UserTarget == CUDAFunctionTarget::Device ||
18596	UserTarget == CUDAFunctionTarget::HostDevice ||
18597	UserTarget == CUDAFunctionTarget::Global)) {
18598	// Diagnose ODR-use of host global variables in device functions.
18599	// Reference of device global variables in host functions is allowed
18600	// through shadow variables therefore it is not diagnosed.
18601	if (SemaRef.LangOpts.CUDAIsDevice && !SemaRef.LangOpts.HIPStdPar) {
18602	SemaRef.targetDiag(Loc, DiagID: diag::err_ref_bad_target)
18603	<< /*host*/ 2 << /*variable*/ 1 << Var << UserTarget;
18604	SemaRef.targetDiag(Loc: Var->getLocation(),
18605	DiagID: Var->getType().isConstQualified()
18606	? diag::note_cuda_const_var_unpromoted
18607	: diag::note_cuda_host_var);
18608	}
18609	} else if (VarTarget == SemaCUDA::CVT_Device &&
18610	!Var->hasAttr<CUDASharedAttr>() &&
18611	(UserTarget == CUDAFunctionTarget::Host ||
18612	UserTarget == CUDAFunctionTarget::HostDevice)) {
18613	// Record a CUDA/HIP device side variable if it is ODR-used
18614	// by host code. This is done conservatively, when the variable is
18615	// referenced in any of the following contexts:
18616	// - a non-function context
18617	// - a host function
18618	// - a host device function
18619	// This makes the ODR-use of the device side variable by host code to
18620	// be visible in the device compilation for the compiler to be able to
18621	// emit template variables instantiated by host code only and to
18622	// externalize the static device side variable ODR-used by host code.
18623	if (!Var->hasExternalStorage())
18624	SemaRef.getASTContext().CUDADeviceVarODRUsedByHost.insert(V: Var);
18625	else if (SemaRef.LangOpts.GPURelocatableDeviceCode &&
18626	(!FD || (!FD->getDescribedFunctionTemplate() &&
18627	SemaRef.getASTContext().GetGVALinkageForFunction(FD) ==
18628	GVA_StrongExternal)))
18629	SemaRef.getASTContext().CUDAExternalDeviceDeclODRUsedByHost.insert(X: Var);
18630	}
18631	}
18632
18633	V->markUsed(C&: SemaRef.Context);
18634	}
18635
18636	void Sema::MarkCaptureUsedInEnclosingContext(ValueDecl *Capture,
18637	SourceLocation Loc,
18638	unsigned CapturingScopeIndex) {
18639	MarkVarDeclODRUsed(V: Capture, Loc, SemaRef&: *this, FunctionScopeIndexToStopAt: &CapturingScopeIndex);
18640	}
18641
18642	void diagnoseUncapturableValueReferenceOrBinding(Sema &S, SourceLocation loc,
18643	ValueDecl *var) {
18644	DeclContext *VarDC = var->getDeclContext();
18645
18646	// If the parameter still belongs to the translation unit, then
18647	// we're actually just using one parameter in the declaration of
18648	// the next.
18649	if (isa<ParmVarDecl>(Val: var) &&
18650	isa<TranslationUnitDecl>(Val: VarDC))
18651	return;
18652
18653	// For C code, don't diagnose about capture if we're not actually in code
18654	// right now; it's impossible to write a non-constant expression outside of
18655	// function context, so we'll get other (more useful) diagnostics later.
18656	//
18657	// For C++, things get a bit more nasty... it would be nice to suppress this
18658	// diagnostic for certain cases like using a local variable in an array bound
18659	// for a member of a local class, but the correct predicate is not obvious.
18660	if (!S.getLangOpts().CPlusPlus && !S.CurContext->isFunctionOrMethod())
18661	return;
18662
18663	unsigned ValueKind = isa<BindingDecl>(Val: var) ? 1 : 0;
18664	unsigned ContextKind = 3; // unknown
18665	if (isa<CXXMethodDecl>(Val: VarDC) &&
18666	cast<CXXRecordDecl>(Val: VarDC->getParent())->isLambda()) {
18667	ContextKind = 2;
18668	} else if (isa<FunctionDecl>(Val: VarDC)) {
18669	ContextKind = 0;
18670	} else if (isa<BlockDecl>(Val: VarDC)) {
18671	ContextKind = 1;
18672	}
18673
18674	S.Diag(Loc: loc, DiagID: diag::err_reference_to_local_in_enclosing_context)
18675	<< var << ValueKind << ContextKind << VarDC;
18676	S.Diag(Loc: var->getLocation(), DiagID: diag::note_entity_declared_at)
18677	<< var;
18678
18679	// FIXME: Add additional diagnostic info about class etc. which prevents
18680	// capture.
18681	}
18682
18683	static bool isVariableAlreadyCapturedInScopeInfo(CapturingScopeInfo *CSI,
18684	ValueDecl *Var,
18685	bool &SubCapturesAreNested,
18686	QualType &CaptureType,
18687	QualType &DeclRefType) {
18688	// Check whether we've already captured it.
18689	if (CSI->CaptureMap.count(Val: Var)) {
18690	// If we found a capture, any subcaptures are nested.
18691	SubCapturesAreNested = true;
18692
18693	// Retrieve the capture type for this variable.
18694	CaptureType = CSI->getCapture(Var).getCaptureType();
18695
18696	// Compute the type of an expression that refers to this variable.
18697	DeclRefType = CaptureType.getNonReferenceType();
18698
18699	// Similarly to mutable captures in lambda, all the OpenMP captures by copy
18700	// are mutable in the sense that user can change their value - they are
18701	// private instances of the captured declarations.
18702	const Capture &Cap = CSI->getCapture(Var);
18703	// C++ [expr.prim.lambda]p10:
18704	// The type of such a data member is [...] an lvalue reference to the
18705	// referenced function type if the entity is a reference to a function.
18706	// [...]
18707	if (Cap.isCopyCapture() && !DeclRefType->isFunctionType() &&
18708	!(isa<LambdaScopeInfo>(Val: CSI) &&
18709	!cast<LambdaScopeInfo>(Val: CSI)->lambdaCaptureShouldBeConst()) &&
18710	!(isa<CapturedRegionScopeInfo>(Val: CSI) &&
18711	cast<CapturedRegionScopeInfo>(Val: CSI)->CapRegionKind == CR_OpenMP))
18712	DeclRefType.addConst();
18713	return true;
18714	}
18715	return false;
18716	}
18717
18718	// Only block literals, captured statements, and lambda expressions can
18719	// capture; other scopes don't work.
18720	static DeclContext *getParentOfCapturingContextOrNull(DeclContext *DC,
18721	ValueDecl *Var,
18722	SourceLocation Loc,
18723	const bool Diagnose,
18724	Sema &S) {
18725	if (isa<BlockDecl>(Val: DC) || isa<CapturedDecl>(Val: DC) || isLambdaCallOperator(DC))
18726	return getLambdaAwareParentOfDeclContext(DC);
18727
18728	VarDecl *Underlying = Var->getPotentiallyDecomposedVarDecl();
18729	if (Underlying) {
18730	if (Underlying->hasLocalStorage() && Diagnose)
18731	diagnoseUncapturableValueReferenceOrBinding(S, loc: Loc, var: Var);
18732	}
18733	return nullptr;
18734	}
18735
18736	// Certain capturing entities (lambdas, blocks etc.) are not allowed to capture
18737	// certain types of variables (unnamed, variably modified types etc.)
18738	// so check for eligibility.
18739	static bool isVariableCapturable(CapturingScopeInfo *CSI, ValueDecl *Var,
18740	SourceLocation Loc, const bool Diagnose,
18741	Sema &S) {
18742
18743	assert((isa<VarDecl, BindingDecl>(Var)) &&
18744	"Only variables and structured bindings can be captured");
18745
18746	bool IsBlock = isa<BlockScopeInfo>(Val: CSI);
18747	bool IsLambda = isa<LambdaScopeInfo>(Val: CSI);
18748
18749	// Lambdas are not allowed to capture unnamed variables
18750	// (e.g. anonymous unions).
18751	// FIXME: The C++11 rule don't actually state this explicitly, but I'm
18752	// assuming that's the intent.
18753	if (IsLambda && !Var->getDeclName()) {
18754	if (Diagnose) {
18755	S.Diag(Loc, DiagID: diag::err_lambda_capture_anonymous_var);
18756	S.Diag(Loc: Var->getLocation(), DiagID: diag::note_declared_at);
18757	}
18758	return false;
18759	}
18760
18761	// Prohibit variably-modified types in blocks; they're difficult to deal with.
18762	if (Var->getType()->isVariablyModifiedType() && IsBlock) {
18763	if (Diagnose) {
18764	S.Diag(Loc, DiagID: diag::err_ref_vm_type);
18765	S.Diag(Loc: Var->getLocation(), DiagID: diag::note_previous_decl) << Var;
18766	}
18767	return false;
18768	}
18769	// Prohibit structs with flexible array members too.
18770	// We cannot capture what is in the tail end of the struct.
18771	if (const RecordType *VTTy = Var->getType()->getAs<RecordType>()) {
18772	if (VTTy->getDecl()->hasFlexibleArrayMember()) {
18773	if (Diagnose) {
18774	if (IsBlock)
18775	S.Diag(Loc, DiagID: diag::err_ref_flexarray_type);
18776	else
18777	S.Diag(Loc, DiagID: diag::err_lambda_capture_flexarray_type) << Var;
18778	S.Diag(Loc: Var->getLocation(), DiagID: diag::note_previous_decl) << Var;
18779	}
18780	return false;
18781	}
18782	}
18783	const bool HasBlocksAttr = Var->hasAttr<BlocksAttr>();
18784	// Lambdas and captured statements are not allowed to capture __block
18785	// variables; they don't support the expected semantics.
18786	if (HasBlocksAttr && (IsLambda || isa<CapturedRegionScopeInfo>(Val: CSI))) {
18787	if (Diagnose) {
18788	S.Diag(Loc, DiagID: diag::err_capture_block_variable) << Var << !IsLambda;
18789	S.Diag(Loc: Var->getLocation(), DiagID: diag::note_previous_decl) << Var;
18790	}
18791	return false;
18792	}
18793	// OpenCL v2.0 s6.12.5: Blocks cannot reference/capture other blocks
18794	if (S.getLangOpts().OpenCL && IsBlock &&
18795	Var->getType()->isBlockPointerType()) {
18796	if (Diagnose)
18797	S.Diag(Loc, DiagID: diag::err_opencl_block_ref_block);
18798	return false;
18799	}
18800
18801	if (isa<BindingDecl>(Val: Var)) {
18802	if (!IsLambda || !S.getLangOpts().CPlusPlus) {
18803	if (Diagnose)
18804	diagnoseUncapturableValueReferenceOrBinding(S, loc: Loc, var: Var);
18805	return false;
18806	} else if (Diagnose && S.getLangOpts().CPlusPlus) {
18807	S.Diag(Loc, DiagID: S.LangOpts.CPlusPlus20
18808	? diag::warn_cxx17_compat_capture_binding
18809	: diag::ext_capture_binding)
18810	<< Var;
18811	S.Diag(Loc: Var->getLocation(), DiagID: diag::note_entity_declared_at) << Var;
18812	}
18813	}
18814
18815	return true;
18816	}
18817
18818	// Returns true if the capture by block was successful.
18819	static bool captureInBlock(BlockScopeInfo *BSI, ValueDecl *Var,
18820	SourceLocation Loc, const bool BuildAndDiagnose,
18821	QualType &CaptureType, QualType &DeclRefType,
18822	const bool Nested, Sema &S, bool Invalid) {
18823	bool ByRef = false;
18824
18825	// Blocks are not allowed to capture arrays, excepting OpenCL.
18826	// OpenCL v2.0 s1.12.5 (revision 40): arrays are captured by reference
18827	// (decayed to pointers).
18828	if (!Invalid && !S.getLangOpts().OpenCL && CaptureType->isArrayType()) {
18829	if (BuildAndDiagnose) {
18830	S.Diag(Loc, DiagID: diag::err_ref_array_type);
18831	S.Diag(Loc: Var->getLocation(), DiagID: diag::note_previous_decl) << Var;
18832	Invalid = true;
18833	} else {
18834	return false;
18835	}
18836	}
18837
18838	// Forbid the block-capture of autoreleasing variables.
18839	if (!Invalid &&
18840	CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) {
18841	if (BuildAndDiagnose) {
18842	S.Diag(Loc, DiagID: diag::err_arc_autoreleasing_capture)
18843	<< /*block*/ 0;
18844	S.Diag(Loc: Var->getLocation(), DiagID: diag::note_previous_decl) << Var;
18845	Invalid = true;
18846	} else {
18847	return false;
18848	}
18849	}
18850
18851	// Warn about implicitly autoreleasing indirect parameters captured by blocks.
18852	if (const auto *PT = CaptureType->getAs<PointerType>()) {
18853	QualType PointeeTy = PT->getPointeeType();
18854
18855	if (!Invalid && PointeeTy->getAs<ObjCObjectPointerType>() &&
18856	PointeeTy.getObjCLifetime() == Qualifiers::OCL_Autoreleasing &&
18857	!S.Context.hasDirectOwnershipQualifier(Ty: PointeeTy)) {
18858	if (BuildAndDiagnose) {
18859	SourceLocation VarLoc = Var->getLocation();
18860	S.Diag(Loc, DiagID: diag::warn_block_capture_autoreleasing);
18861	S.Diag(Loc: VarLoc, DiagID: diag::note_declare_parameter_strong);
18862	}
18863	}
18864	}
18865
18866	const bool HasBlocksAttr = Var->hasAttr<BlocksAttr>();
18867	if (HasBlocksAttr || CaptureType->isReferenceType() ||
18868	(S.getLangOpts().OpenMP && S.OpenMP().isOpenMPCapturedDecl(D: Var))) {
18869	// Block capture by reference does not change the capture or
18870	// declaration reference types.
18871	ByRef = true;
18872	} else {
18873	// Block capture by copy introduces 'const'.
18874	CaptureType = CaptureType.getNonReferenceType().withConst();
18875	DeclRefType = CaptureType;
18876	}
18877
18878	// Actually capture the variable.
18879	if (BuildAndDiagnose)
18880	BSI->addCapture(Var, isBlock: HasBlocksAttr, isByref: ByRef, isNested: Nested, Loc, EllipsisLoc: SourceLocation(),
18881	CaptureType, Invalid);
18882
18883	return !Invalid;
18884	}
18885
18886	/// Capture the given variable in the captured region.
18887	static bool captureInCapturedRegion(
18888	CapturedRegionScopeInfo *RSI, ValueDecl *Var, SourceLocation Loc,
18889	const bool BuildAndDiagnose, QualType &CaptureType, QualType &DeclRefType,
18890	const bool RefersToCapturedVariable, TryCaptureKind Kind, bool IsTopScope,
18891	Sema &S, bool Invalid) {
18892	// By default, capture variables by reference.
18893	bool ByRef = true;
18894	if (IsTopScope && Kind != TryCaptureKind::Implicit) {
18895	ByRef = (Kind == TryCaptureKind::ExplicitByRef);
18896	} else if (S.getLangOpts().OpenMP && RSI->CapRegionKind == CR_OpenMP) {
18897	// Using an LValue reference type is consistent with Lambdas (see below).
18898	if (S.OpenMP().isOpenMPCapturedDecl(D: Var)) {
18899	bool HasConst = DeclRefType.isConstQualified();
18900	DeclRefType = DeclRefType.getUnqualifiedType();
18901	// Don't lose diagnostics about assignments to const.
18902	if (HasConst)
18903	DeclRefType.addConst();
18904	}
18905	// Do not capture firstprivates in tasks.
18906	if (S.OpenMP().isOpenMPPrivateDecl(D: Var, Level: RSI->OpenMPLevel,
18907	CapLevel: RSI->OpenMPCaptureLevel) != OMPC_unknown)
18908	return true;
18909	ByRef = S.OpenMP().isOpenMPCapturedByRef(D: Var, Level: RSI->OpenMPLevel,
18910	OpenMPCaptureLevel: RSI->OpenMPCaptureLevel);
18911	}
18912
18913	if (ByRef)
18914	CaptureType = S.Context.getLValueReferenceType(T: DeclRefType);
18915	else
18916	CaptureType = DeclRefType;
18917
18918	// Actually capture the variable.
18919	if (BuildAndDiagnose)
18920	RSI->addCapture(Var, /*isBlock*/ false, isByref: ByRef, isNested: RefersToCapturedVariable,
18921	Loc, EllipsisLoc: SourceLocation(), CaptureType, Invalid);
18922
18923	return !Invalid;
18924	}
18925
18926	/// Capture the given variable in the lambda.
18927	static bool captureInLambda(LambdaScopeInfo *LSI, ValueDecl *Var,
18928	SourceLocation Loc, const bool BuildAndDiagnose,
18929	QualType &CaptureType, QualType &DeclRefType,
18930	const bool RefersToCapturedVariable,
18931	const TryCaptureKind Kind,
18932	SourceLocation EllipsisLoc, const bool IsTopScope,
18933	Sema &S, bool Invalid) {
18934	// Determine whether we are capturing by reference or by value.
18935	bool ByRef = false;
18936	if (IsTopScope && Kind != TryCaptureKind::Implicit) {
18937	ByRef = (Kind == TryCaptureKind::ExplicitByRef);
18938	} else {
18939	ByRef = (LSI->ImpCaptureStyle == LambdaScopeInfo::ImpCap_LambdaByref);
18940	}
18941
18942	if (BuildAndDiagnose && S.Context.getTargetInfo().getTriple().isWasm() &&
18943	CaptureType.getNonReferenceType().isWebAssemblyReferenceType()) {
18944	S.Diag(Loc, DiagID: diag::err_wasm_ca_reference) << 0;
18945	Invalid = true;
18946	}
18947
18948	// Compute the type of the field that will capture this variable.
18949	if (ByRef) {
18950	// C++11 [expr.prim.lambda]p15:
18951	// An entity is captured by reference if it is implicitly or
18952	// explicitly captured but not captured by copy. It is
18953	// unspecified whether additional unnamed non-static data
18954	// members are declared in the closure type for entities
18955	// captured by reference.
18956	//
18957	// FIXME: It is not clear whether we want to build an lvalue reference
18958	// to the DeclRefType or to CaptureType.getNonReferenceType(). GCC appears
18959	// to do the former, while EDG does the latter. Core issue 1249 will
18960	// clarify, but for now we follow GCC because it's a more permissive and
18961	// easily defensible position.
18962	CaptureType = S.Context.getLValueReferenceType(T: DeclRefType);
18963	} else {
18964	// C++11 [expr.prim.lambda]p14:
18965	// For each entity captured by copy, an unnamed non-static
18966	// data member is declared in the closure type. The
18967	// declaration order of these members is unspecified. The type
18968	// of such a data member is the type of the corresponding
18969	// captured entity if the entity is not a reference to an
18970	// object, or the referenced type otherwise. [Note: If the
18971	// captured entity is a reference to a function, the
18972	// corresponding data member is also a reference to a
18973	// function. - end note ]
18974	if (const ReferenceType *RefType = CaptureType->getAs<ReferenceType>()){
18975	if (!RefType->getPointeeType()->isFunctionType())
18976	CaptureType = RefType->getPointeeType();
18977	}
18978
18979	// Forbid the lambda copy-capture of autoreleasing variables.
18980	if (!Invalid &&
18981	CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) {
18982	if (BuildAndDiagnose) {
18983	S.Diag(Loc, DiagID: diag::err_arc_autoreleasing_capture) << /*lambda*/ 1;
18984	S.Diag(Loc: Var->getLocation(), DiagID: diag::note_previous_decl)
18985	<< Var->getDeclName();
18986	Invalid = true;
18987	} else {
18988	return false;
18989	}
18990	}
18991
18992	// Make sure that by-copy captures are of a complete and non-abstract type.
18993	if (!Invalid && BuildAndDiagnose) {
18994	if (!CaptureType->isDependentType() &&
18995	S.RequireCompleteSizedType(
18996	Loc, T: CaptureType,
18997	DiagID: diag::err_capture_of_incomplete_or_sizeless_type,
18998	Args: Var->getDeclName()))
18999	Invalid = true;
19000	else if (S.RequireNonAbstractType(Loc, T: CaptureType,
19001	DiagID: diag::err_capture_of_abstract_type))
19002	Invalid = true;
19003	}
19004	}
19005
19006	// Compute the type of a reference to this captured variable.
19007	if (ByRef)
19008	DeclRefType = CaptureType.getNonReferenceType();
19009	else {
19010	// C++ [expr.prim.lambda]p5:
19011	// The closure type for a lambda-expression has a public inline
19012	// function call operator [...]. This function call operator is
19013	// declared const (9.3.1) if and only if the lambda-expression's
19014	// parameter-declaration-clause is not followed by mutable.
19015	DeclRefType = CaptureType.getNonReferenceType();
19016	bool Const = LSI->lambdaCaptureShouldBeConst();
19017	// C++ [expr.prim.lambda]p10:
19018	// The type of such a data member is [...] an lvalue reference to the
19019	// referenced function type if the entity is a reference to a function.
19020	// [...]
19021	if (Const && !CaptureType->isReferenceType() &&
19022	!DeclRefType->isFunctionType())
19023	DeclRefType.addConst();
19024	}
19025
19026	// Add the capture.
19027	if (BuildAndDiagnose)
19028	LSI->addCapture(Var, /*isBlock=*/false, isByref: ByRef, isNested: RefersToCapturedVariable,
19029	Loc, EllipsisLoc, CaptureType, Invalid);
19030
19031	return !Invalid;
19032	}
19033
19034	static bool canCaptureVariableByCopy(ValueDecl *Var,
19035	const ASTContext &Context) {
19036	// Offer a Copy fix even if the type is dependent.
19037	if (Var->getType()->isDependentType())
19038	return true;
19039	QualType T = Var->getType().getNonReferenceType();
19040	if (T.isTriviallyCopyableType(Context))
19041	return true;
19042	if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
19043
19044	if (!(RD = RD->getDefinition()))
19045	return false;
19046	if (RD->hasSimpleCopyConstructor())
19047	return true;
19048	if (RD->hasUserDeclaredCopyConstructor())
19049	for (CXXConstructorDecl *Ctor : RD->ctors())
19050	if (Ctor->isCopyConstructor())
19051	return !Ctor->isDeleted();
19052	}
19053	return false;
19054	}
19055
19056	/// Create up to 4 fix-its for explicit reference and value capture of \p Var or
19057	/// default capture. Fixes may be omitted if they aren't allowed by the
19058	/// standard, for example we can't emit a default copy capture fix-it if we
19059	/// already explicitly copy capture capture another variable.
19060	static void buildLambdaCaptureFixit(Sema &Sema, LambdaScopeInfo *LSI,
19061	ValueDecl *Var) {
19062	assert(LSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None);
19063	// Don't offer Capture by copy of default capture by copy fixes if Var is
19064	// known not to be copy constructible.
19065	bool ShouldOfferCopyFix = canCaptureVariableByCopy(Var, Context: Sema.getASTContext());
19066
19067	SmallString<32> FixBuffer;
19068	StringRef Separator = LSI->NumExplicitCaptures > 0 ? ", " : "";
19069	if (Var->getDeclName().isIdentifier() && !Var->getName().empty()) {
19070	SourceLocation VarInsertLoc = LSI->IntroducerRange.getEnd();
19071	if (ShouldOfferCopyFix) {
19072	// Offer fixes to insert an explicit capture for the variable.
19073	// [] -> [VarName]
19074	// [OtherCapture] -> [OtherCapture, VarName]
19075	FixBuffer.assign(Refs: {Separator, Var->getName()});
19076	Sema.Diag(Loc: VarInsertLoc, DiagID: diag::note_lambda_variable_capture_fixit)
19077	<< Var << /*value*/ 0
19078	<< FixItHint::CreateInsertion(InsertionLoc: VarInsertLoc, Code: FixBuffer);
19079	}
19080	// As above but capture by reference.
19081	FixBuffer.assign(Refs: {Separator, "&", Var->getName()});
19082	Sema.Diag(Loc: VarInsertLoc, DiagID: diag::note_lambda_variable_capture_fixit)
19083	<< Var << /*reference*/ 1
19084	<< FixItHint::CreateInsertion(InsertionLoc: VarInsertLoc, Code: FixBuffer);
19085	}
19086
19087	// Only try to offer default capture if there are no captures excluding this
19088	// and init captures.
19089	// [this]: OK.
19090	// [X = Y]: OK.
19091	// [&A, &B]: Don't offer.
19092	// [A, B]: Don't offer.
19093	if (llvm::any_of(Range&: LSI->Captures, P: [](Capture &C) {
19094	return !C.isThisCapture() && !C.isInitCapture();
19095	}))
19096	return;
19097
19098	// The default capture specifiers, '=' or '&', must appear first in the
19099	// capture body.
19100	SourceLocation DefaultInsertLoc =
19101	LSI->IntroducerRange.getBegin().getLocWithOffset(Offset: 1);
19102
19103	if (ShouldOfferCopyFix) {
19104	bool CanDefaultCopyCapture = true;
19105	// [=, *this] OK since c++17
19106	// [=, this] OK since c++20
19107	if (LSI->isCXXThisCaptured() && !Sema.getLangOpts().CPlusPlus20)
19108	CanDefaultCopyCapture = Sema.getLangOpts().CPlusPlus17
19109	? LSI->getCXXThisCapture().isCopyCapture()
19110	: false;
19111	// We can't use default capture by copy if any captures already specified
19112	// capture by copy.
19113	if (CanDefaultCopyCapture && llvm::none_of(Range&: LSI->Captures, P: [](Capture &C) {
19114	return !C.isThisCapture() && !C.isInitCapture() && C.isCopyCapture();
19115	})) {
19116	FixBuffer.assign(Refs: {"=", Separator});
19117	Sema.Diag(Loc: DefaultInsertLoc, DiagID: diag::note_lambda_default_capture_fixit)
19118	<< /*value*/ 0
19119	<< FixItHint::CreateInsertion(InsertionLoc: DefaultInsertLoc, Code: FixBuffer);
19120	}
19121	}
19122
19123	// We can't use default capture by reference if any captures already specified
19124	// capture by reference.
19125	if (llvm::none_of(Range&: LSI->Captures, P: [](Capture &C) {
19126	return !C.isInitCapture() && C.isReferenceCapture() &&
19127	!C.isThisCapture();
19128	})) {
19129	FixBuffer.assign(Refs: {"&", Separator});
19130	Sema.Diag(Loc: DefaultInsertLoc, DiagID: diag::note_lambda_default_capture_fixit)
19131	<< /*reference*/ 1
19132	<< FixItHint::CreateInsertion(InsertionLoc: DefaultInsertLoc, Code: FixBuffer);
19133	}
19134	}
19135
19136	bool Sema::tryCaptureVariable(
19137	ValueDecl *Var, SourceLocation ExprLoc, TryCaptureKind Kind,
19138	SourceLocation EllipsisLoc, bool BuildAndDiagnose, QualType &CaptureType,
19139	QualType &DeclRefType, const unsigned *const FunctionScopeIndexToStopAt) {
19140	// An init-capture is notionally from the context surrounding its
19141	// declaration, but its parent DC is the lambda class.
19142	DeclContext *VarDC = Var->getDeclContext();
19143	DeclContext *DC = CurContext;
19144
19145	// Skip past RequiresExprBodys because they don't constitute function scopes.
19146	while (DC->isRequiresExprBody())
19147	DC = DC->getParent();
19148
19149	// tryCaptureVariable is called every time a DeclRef is formed,
19150	// it can therefore have non-negigible impact on performances.
19151	// For local variables and when there is no capturing scope,
19152	// we can bailout early.
19153	if (CapturingFunctionScopes == 0 && (!BuildAndDiagnose || VarDC == DC))
19154	return true;
19155
19156	// Exception: Function parameters are not tied to the function's DeclContext
19157	// until we enter the function definition. Capturing them anyway would result
19158	// in an out-of-bounds error while traversing DC and its parents.
19159	if (isa<ParmVarDecl>(Val: Var) && !VarDC->isFunctionOrMethod())
19160	return true;
19161
19162	const auto *VD = dyn_cast<VarDecl>(Val: Var);
19163	if (VD) {
19164	if (VD->isInitCapture())
19165	VarDC = VarDC->getParent();
19166	} else {
19167	VD = Var->getPotentiallyDecomposedVarDecl();
19168	}
19169	assert(VD && "Cannot capture a null variable");
19170
19171	const unsigned MaxFunctionScopesIndex = FunctionScopeIndexToStopAt
19172	? *FunctionScopeIndexToStopAt : FunctionScopes.size() - 1;
19173	// We need to sync up the Declaration Context with the
19174	// FunctionScopeIndexToStopAt
19175	if (FunctionScopeIndexToStopAt) {
19176	assert(!FunctionScopes.empty() && "No function scopes to stop at?");
19177	unsigned FSIndex = FunctionScopes.size() - 1;
19178	// When we're parsing the lambda parameter list, the current DeclContext is
19179	// NOT the lambda but its parent. So move away the current LSI before
19180	// aligning DC and FunctionScopeIndexToStopAt.
19181	if (auto *LSI = dyn_cast<LambdaScopeInfo>(Val: FunctionScopes[FSIndex]);
19182	FSIndex && LSI && !LSI->AfterParameterList)
19183	--FSIndex;
19184	assert(MaxFunctionScopesIndex <= FSIndex &&
19185	"FunctionScopeIndexToStopAt should be no greater than FSIndex into "
19186	"FunctionScopes.");
19187	while (FSIndex != MaxFunctionScopesIndex) {
19188	DC = getLambdaAwareParentOfDeclContext(DC);
19189	--FSIndex;
19190	}
19191	}
19192
19193	// Capture global variables if it is required to use private copy of this
19194	// variable.
19195	bool IsGlobal = !VD->hasLocalStorage();
19196	if (IsGlobal && !(LangOpts.OpenMP &&
19197	OpenMP().isOpenMPCapturedDecl(D: Var, /*CheckScopeInfo=*/true,
19198	StopAt: MaxFunctionScopesIndex)))
19199	return true;
19200
19201	if (isa<VarDecl>(Val: Var))
19202	Var = cast<VarDecl>(Val: Var->getCanonicalDecl());
19203
19204	// Walk up the stack to determine whether we can capture the variable,
19205	// performing the "simple" checks that don't depend on type. We stop when
19206	// we've either hit the declared scope of the variable or find an existing
19207	// capture of that variable. We start from the innermost capturing-entity
19208	// (the DC) and ensure that all intervening capturing-entities
19209	// (blocks/lambdas etc.) between the innermost capturer and the variable`s
19210	// declcontext can either capture the variable or have already captured
19211	// the variable.
19212	CaptureType = Var->getType();
19213	DeclRefType = CaptureType.getNonReferenceType();
19214	bool Nested = false;
19215	bool Explicit = (Kind != TryCaptureKind::Implicit);
19216	unsigned FunctionScopesIndex = MaxFunctionScopesIndex;
19217	do {
19218
19219	LambdaScopeInfo *LSI = nullptr;
19220	if (!FunctionScopes.empty())
19221	LSI = dyn_cast_or_null<LambdaScopeInfo>(
19222	Val: FunctionScopes[FunctionScopesIndex]);
19223
19224	bool IsInScopeDeclarationContext =
19225	!LSI || LSI->AfterParameterList || CurContext == LSI->CallOperator;
19226
19227	if (LSI && !LSI->AfterParameterList) {
19228	// This allows capturing parameters from a default value which does not
19229	// seems correct
19230	if (isa<ParmVarDecl>(Val: Var) && !Var->getDeclContext()->isFunctionOrMethod())
19231	return true;
19232	}
19233	// If the variable is declared in the current context, there is no need to
19234	// capture it.
19235	if (IsInScopeDeclarationContext &&
19236	FunctionScopesIndex == MaxFunctionScopesIndex && VarDC == DC)
19237	return true;
19238
19239	// Only block literals, captured statements, and lambda expressions can
19240	// capture; other scopes don't work.
19241	DeclContext *ParentDC =
19242	!IsInScopeDeclarationContext
19243	? DC->getParent()
19244	: getParentOfCapturingContextOrNull(DC, Var, Loc: ExprLoc,
19245	Diagnose: BuildAndDiagnose, S&: *this);
19246	// We need to check for the parent *first* because, if we *have*
19247	// private-captured a global variable, we need to recursively capture it in
19248	// intermediate blocks, lambdas, etc.
19249	if (!ParentDC) {
19250	if (IsGlobal) {
19251	FunctionScopesIndex = MaxFunctionScopesIndex - 1;
19252	break;
19253	}
19254	return true;
19255	}
19256
19257	FunctionScopeInfo *FSI = FunctionScopes[FunctionScopesIndex];
19258	CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(Val: FSI);
19259
19260	// Check whether we've already captured it.
19261	if (isVariableAlreadyCapturedInScopeInfo(CSI, Var, SubCapturesAreNested&: Nested, CaptureType,
19262	DeclRefType)) {
19263	CSI->getCapture(Var).markUsed(IsODRUse: BuildAndDiagnose);
19264	break;
19265	}
19266
19267	// When evaluating some attributes (like enable_if) we might refer to a
19268	// function parameter appertaining to the same declaration as that
19269	// attribute.
19270	if (const auto *Parm = dyn_cast<ParmVarDecl>(Val: Var);
19271	Parm && Parm->getDeclContext() == DC)
19272	return true;
19273
19274	// If we are instantiating a generic lambda call operator body,
19275	// we do not want to capture new variables. What was captured
19276	// during either a lambdas transformation or initial parsing
19277	// should be used.
19278	if (isGenericLambdaCallOperatorSpecialization(DC)) {
19279	if (BuildAndDiagnose) {
19280	LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(Val: CSI);
19281	if (LSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None) {
19282	Diag(Loc: ExprLoc, DiagID: diag::err_lambda_impcap) << Var;
19283	Diag(Loc: Var->getLocation(), DiagID: diag::note_previous_decl) << Var;
19284	Diag(Loc: LSI->Lambda->getBeginLoc(), DiagID: diag::note_lambda_decl);
19285	buildLambdaCaptureFixit(Sema&: *this, LSI, Var);
19286	} else
19287	diagnoseUncapturableValueReferenceOrBinding(S&: *this, loc: ExprLoc, var: Var);
19288	}
19289	return true;
19290	}
19291
19292	// Try to capture variable-length arrays types.
19293	if (Var->getType()->isVariablyModifiedType()) {
19294	// We're going to walk down into the type and look for VLA
19295	// expressions.
19296	QualType QTy = Var->getType();
19297	if (ParmVarDecl *PVD = dyn_cast_or_null<ParmVarDecl>(Val: Var))
19298	QTy = PVD->getOriginalType();
19299	captureVariablyModifiedType(Context, T: QTy, CSI);
19300	}
19301
19302	if (getLangOpts().OpenMP) {
19303	if (auto *RSI = dyn_cast<CapturedRegionScopeInfo>(Val: CSI)) {
19304	// OpenMP private variables should not be captured in outer scope, so
19305	// just break here. Similarly, global variables that are captured in a
19306	// target region should not be captured outside the scope of the region.
19307	if (RSI->CapRegionKind == CR_OpenMP) {
19308	// FIXME: We should support capturing structured bindings in OpenMP.
19309	if (isa<BindingDecl>(Val: Var)) {
19310	if (BuildAndDiagnose) {
19311	Diag(Loc: ExprLoc, DiagID: diag::err_capture_binding_openmp) << Var;
19312	Diag(Loc: Var->getLocation(), DiagID: diag::note_entity_declared_at) << Var;
19313	}
19314	return true;
19315	}
19316	OpenMPClauseKind IsOpenMPPrivateDecl = OpenMP().isOpenMPPrivateDecl(
19317	D: Var, Level: RSI->OpenMPLevel, CapLevel: RSI->OpenMPCaptureLevel);
19318	// If the variable is private (i.e. not captured) and has variably
19319	// modified type, we still need to capture the type for correct
19320	// codegen in all regions, associated with the construct. Currently,
19321	// it is captured in the innermost captured region only.
19322	if (IsOpenMPPrivateDecl != OMPC_unknown &&
19323	Var->getType()->isVariablyModifiedType()) {
19324	QualType QTy = Var->getType();
19325	if (ParmVarDecl *PVD = dyn_cast_or_null<ParmVarDecl>(Val: Var))
19326	QTy = PVD->getOriginalType();
19327	for (int I = 1,
19328	E = OpenMP().getNumberOfConstructScopes(Level: RSI->OpenMPLevel);
19329	I < E; ++I) {
19330	auto *OuterRSI = cast<CapturedRegionScopeInfo>(
19331	Val: FunctionScopes[FunctionScopesIndex - I]);
19332	assert(RSI->OpenMPLevel == OuterRSI->OpenMPLevel &&
19333	"Wrong number of captured regions associated with the "
19334	"OpenMP construct.");
19335	captureVariablyModifiedType(Context, T: QTy, CSI: OuterRSI);
19336	}
19337	}
19338	bool IsTargetCap =
19339	IsOpenMPPrivateDecl != OMPC_private &&
19340	OpenMP().isOpenMPTargetCapturedDecl(D: Var, Level: RSI->OpenMPLevel,
19341	CaptureLevel: RSI->OpenMPCaptureLevel);
19342	// Do not capture global if it is not privatized in outer regions.
19343	bool IsGlobalCap =
19344	IsGlobal && OpenMP().isOpenMPGlobalCapturedDecl(
19345	D: Var, Level: RSI->OpenMPLevel, CaptureLevel: RSI->OpenMPCaptureLevel);
19346
19347	// When we detect target captures we are looking from inside the
19348	// target region, therefore we need to propagate the capture from the
19349	// enclosing region. Therefore, the capture is not initially nested.
19350	if (IsTargetCap)
19351	OpenMP().adjustOpenMPTargetScopeIndex(FunctionScopesIndex,
19352	Level: RSI->OpenMPLevel);
19353
19354	if (IsTargetCap || IsOpenMPPrivateDecl == OMPC_private ||
19355	(IsGlobal && !IsGlobalCap)) {
19356	Nested = !IsTargetCap;
19357	bool HasConst = DeclRefType.isConstQualified();
19358	DeclRefType = DeclRefType.getUnqualifiedType();
19359	// Don't lose diagnostics about assignments to const.
19360	if (HasConst)
19361	DeclRefType.addConst();
19362	CaptureType = Context.getLValueReferenceType(T: DeclRefType);
19363	break;
19364	}
19365	}
19366	}
19367	}
19368	if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None && !Explicit) {
19369	// No capture-default, and this is not an explicit capture
19370	// so cannot capture this variable.
19371	if (BuildAndDiagnose) {
19372	Diag(Loc: ExprLoc, DiagID: diag::err_lambda_impcap) << Var;
19373	Diag(Loc: Var->getLocation(), DiagID: diag::note_previous_decl) << Var;
19374	auto *LSI = cast<LambdaScopeInfo>(Val: CSI);
19375	if (LSI->Lambda) {
19376	Diag(Loc: LSI->Lambda->getBeginLoc(), DiagID: diag::note_lambda_decl);
19377	buildLambdaCaptureFixit(Sema&: *this, LSI, Var);
19378	}
19379	// FIXME: If we error out because an outer lambda can not implicitly
19380	// capture a variable that an inner lambda explicitly captures, we
19381	// should have the inner lambda do the explicit capture - because
19382	// it makes for cleaner diagnostics later. This would purely be done
19383	// so that the diagnostic does not misleadingly claim that a variable
19384	// can not be captured by a lambda implicitly even though it is captured
19385	// explicitly. Suggestion:
19386	// - create const bool VariableCaptureWasInitiallyExplicit = Explicit
19387	// at the function head
19388	// - cache the StartingDeclContext - this must be a lambda
19389	// - captureInLambda in the innermost lambda the variable.
19390	}
19391	return true;
19392	}
19393	Explicit = false;
19394	FunctionScopesIndex--;
19395	if (IsInScopeDeclarationContext)
19396	DC = ParentDC;
19397	} while (!VarDC->Equals(DC));
19398
19399	// Walk back down the scope stack, (e.g. from outer lambda to inner lambda)
19400	// computing the type of the capture at each step, checking type-specific
19401	// requirements, and adding captures if requested.
19402	// If the variable had already been captured previously, we start capturing
19403	// at the lambda nested within that one.
19404	bool Invalid = false;
19405	for (unsigned I = ++FunctionScopesIndex, N = MaxFunctionScopesIndex + 1; I != N;
19406	++I) {
19407	CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(Val: FunctionScopes[I]);
19408
19409	// Certain capturing entities (lambdas, blocks etc.) are not allowed to capture
19410	// certain types of variables (unnamed, variably modified types etc.)
19411	// so check for eligibility.
19412	if (!Invalid)
19413	Invalid =
19414	!isVariableCapturable(CSI, Var, Loc: ExprLoc, Diagnose: BuildAndDiagnose, S&: *this);
19415
19416	// After encountering an error, if we're actually supposed to capture, keep
19417	// capturing in nested contexts to suppress any follow-on diagnostics.
19418	if (Invalid && !BuildAndDiagnose)
19419	return true;
19420
19421	if (BlockScopeInfo *BSI = dyn_cast<BlockScopeInfo>(Val: CSI)) {
19422	Invalid = !captureInBlock(BSI, Var, Loc: ExprLoc, BuildAndDiagnose, CaptureType,
19423	DeclRefType, Nested, S&: *this, Invalid);
19424	Nested = true;
19425	} else if (CapturedRegionScopeInfo *RSI = dyn_cast<CapturedRegionScopeInfo>(Val: CSI)) {
19426	Invalid = !captureInCapturedRegion(
19427	RSI, Var, Loc: ExprLoc, BuildAndDiagnose, CaptureType, DeclRefType, RefersToCapturedVariable: Nested,
19428	Kind, /*IsTopScope*/ I == N - 1, S&: *this, Invalid);
19429	Nested = true;
19430	} else {
19431	LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(Val: CSI);
19432	Invalid =
19433	!captureInLambda(LSI, Var, Loc: ExprLoc, BuildAndDiagnose, CaptureType,
19434	DeclRefType, RefersToCapturedVariable: Nested, Kind, EllipsisLoc,
19435	/*IsTopScope*/ I == N - 1, S&: *this, Invalid);
19436	Nested = true;
19437	}
19438
19439	if (Invalid && !BuildAndDiagnose)
19440	return true;
19441	}
19442	return Invalid;
19443	}
19444
19445	bool Sema::tryCaptureVariable(ValueDecl *Var, SourceLocation Loc,
19446	TryCaptureKind Kind, SourceLocation EllipsisLoc) {
19447	QualType CaptureType;
19448	QualType DeclRefType;
19449	return tryCaptureVariable(Var, ExprLoc: Loc, Kind, EllipsisLoc,
19450	/*BuildAndDiagnose=*/true, CaptureType,
19451	DeclRefType, FunctionScopeIndexToStopAt: nullptr);
19452	}
19453
19454	bool Sema::NeedToCaptureVariable(ValueDecl *Var, SourceLocation Loc) {
19455	QualType CaptureType;
19456	QualType DeclRefType;
19457	return !tryCaptureVariable(
19458	Var, ExprLoc: Loc, Kind: TryCaptureKind::Implicit, EllipsisLoc: SourceLocation(),
19459	/*BuildAndDiagnose=*/false, CaptureType, DeclRefType, FunctionScopeIndexToStopAt: nullptr);
19460	}
19461
19462	QualType Sema::getCapturedDeclRefType(ValueDecl *Var, SourceLocation Loc) {
19463	assert(Var && "Null value cannot be captured");
19464
19465	QualType CaptureType;
19466	QualType DeclRefType;
19467
19468	// Determine whether we can capture this variable.
19469	if (tryCaptureVariable(Var, ExprLoc: Loc, Kind: TryCaptureKind::Implicit, EllipsisLoc: SourceLocation(),
19470	/*BuildAndDiagnose=*/false, CaptureType, DeclRefType,
19471	FunctionScopeIndexToStopAt: nullptr))
19472	return QualType();
19473
19474	return DeclRefType;
19475	}
19476
19477	namespace {
19478	// Helper to copy the template arguments from a DeclRefExpr or MemberExpr.
19479	// The produced TemplateArgumentListInfo* points to data stored within this
19480	// object, so should only be used in contexts where the pointer will not be
19481	// used after the CopiedTemplateArgs object is destroyed.
19482	class CopiedTemplateArgs {
19483	bool HasArgs;
19484	TemplateArgumentListInfo TemplateArgStorage;
19485	public:
19486	template<typename RefExpr>
19487	CopiedTemplateArgs(RefExpr *E) : HasArgs(E->hasExplicitTemplateArgs()) {
19488	if (HasArgs)
19489	E->copyTemplateArgumentsInto(TemplateArgStorage);
19490	}
19491	operator TemplateArgumentListInfo*()
19492	#ifdef __has_cpp_attribute
19493	#if __has_cpp_attribute(clang::lifetimebound)
19494	[[clang::lifetimebound]]
19495	#endif
19496	#endif
19497	{
19498	return HasArgs ? &TemplateArgStorage : nullptr;
19499	}
19500	};
19501	}
19502
19503	/// Walk the set of potential results of an expression and mark them all as
19504	/// non-odr-uses if they satisfy the side-conditions of the NonOdrUseReason.
19505	///
19506	/// \return A new expression if we found any potential results, ExprEmpty() if
19507	/// not, and ExprError() if we diagnosed an error.
19508	static ExprResult rebuildPotentialResultsAsNonOdrUsed(Sema &S, Expr *E,
19509	NonOdrUseReason NOUR) {
19510	// Per C++11 [basic.def.odr], a variable is odr-used "unless it is
19511	// an object that satisfies the requirements for appearing in a
19512	// constant expression (5.19) and the lvalue-to-rvalue conversion (4.1)
19513	// is immediately applied." This function handles the lvalue-to-rvalue
19514	// conversion part.
19515	//
19516	// If we encounter a node that claims to be an odr-use but shouldn't be, we
19517	// transform it into the relevant kind of non-odr-use node and rebuild the
19518	// tree of nodes leading to it.
19519	//
19520	// This is a mini-TreeTransform that only transforms a restricted subset of
19521	// nodes (and only certain operands of them).
19522
19523	// Rebuild a subexpression.
19524	auto Rebuild = [&](Expr *Sub) {
19525	return rebuildPotentialResultsAsNonOdrUsed(S, E: Sub, NOUR);
19526	};
19527
19528	// Check whether a potential result satisfies the requirements of NOUR.
19529	auto IsPotentialResultOdrUsed = [&](NamedDecl *D) {
19530	// Any entity other than a VarDecl is always odr-used whenever it's named
19531	// in a potentially-evaluated expression.
19532	auto *VD = dyn_cast<VarDecl>(Val: D);
19533	if (!VD)
19534	return true;
19535
19536	// C++2a [basic.def.odr]p4:
19537	// A variable x whose name appears as a potentially-evalauted expression
19538	// e is odr-used by e unless
19539	// -- x is a reference that is usable in constant expressions, or
19540	// -- x is a variable of non-reference type that is usable in constant
19541	// expressions and has no mutable subobjects, and e is an element of
19542	// the set of potential results of an expression of
19543	// non-volatile-qualified non-class type to which the lvalue-to-rvalue
19544	// conversion is applied, or
19545	// -- x is a variable of non-reference type, and e is an element of the
19546	// set of potential results of a discarded-value expression to which
19547	// the lvalue-to-rvalue conversion is not applied
19548	//
19549	// We check the first bullet and the "potentially-evaluated" condition in
19550	// BuildDeclRefExpr. We check the type requirements in the second bullet
19551	// in CheckLValueToRValueConversionOperand below.
19552	switch (NOUR) {
19553	case NOUR_None:
19554	case NOUR_Unevaluated:
19555	llvm_unreachable("unexpected non-odr-use-reason");
19556
19557	case NOUR_Constant:
19558	// Constant references were handled when they were built.
19559	if (VD->getType()->isReferenceType())
19560	return true;
19561	if (auto *RD = VD->getType()->getAsCXXRecordDecl())
19562	if (RD->hasDefinition() && RD->hasMutableFields())
19563	return true;
19564	if (!VD->isUsableInConstantExpressions(C: S.Context))
19565	return true;
19566	break;
19567
19568	case NOUR_Discarded:
19569	if (VD->getType()->isReferenceType())
19570	return true;
19571	break;
19572	}
19573	return false;
19574	};
19575
19576	// Check whether this expression may be odr-used in CUDA/HIP.
19577	auto MaybeCUDAODRUsed = [&]() -> bool {
19578	if (!S.LangOpts.CUDA)
19579	return false;
19580	LambdaScopeInfo *LSI = S.getCurLambda();
19581	if (!LSI)
19582	return false;
19583	auto *DRE = dyn_cast<DeclRefExpr>(Val: E);
19584	if (!DRE)
19585	return false;
19586	auto *VD = dyn_cast<VarDecl>(Val: DRE->getDecl());
19587	if (!VD)
19588	return false;
19589	return LSI->CUDAPotentialODRUsedVars.count(Ptr: VD);
19590	};
19591
19592	// Mark that this expression does not constitute an odr-use.
19593	auto MarkNotOdrUsed = [&] {
19594	if (!MaybeCUDAODRUsed()) {
19595	S.MaybeODRUseExprs.remove(X: E);
19596	if (LambdaScopeInfo *LSI = S.getCurLambda())
19597	LSI->markVariableExprAsNonODRUsed(CapturingVarExpr: E);
19598	}
19599	};
19600
19601	// C++2a [basic.def.odr]p2:
19602	// The set of potential results of an expression e is defined as follows:
19603	switch (E->getStmtClass()) {
19604	// -- If e is an id-expression, ...
19605	case Expr::DeclRefExprClass: {
19606	auto *DRE = cast<DeclRefExpr>(Val: E);
19607	if (DRE->isNonOdrUse() || IsPotentialResultOdrUsed(DRE->getDecl()))
19608	break;
19609
19610	// Rebuild as a non-odr-use DeclRefExpr.
19611	MarkNotOdrUsed();
19612	return DeclRefExpr::Create(
19613	Context: S.Context, QualifierLoc: DRE->getQualifierLoc(), TemplateKWLoc: DRE->getTemplateKeywordLoc(),
19614	D: DRE->getDecl(), RefersToEnclosingVariableOrCapture: DRE->refersToEnclosingVariableOrCapture(),
19615	NameInfo: DRE->getNameInfo(), T: DRE->getType(), VK: DRE->getValueKind(),
19616	FoundD: DRE->getFoundDecl(), TemplateArgs: CopiedTemplateArgs(DRE), NOUR);
19617	}
19618
19619	case Expr::FunctionParmPackExprClass: {
19620	auto *FPPE = cast<FunctionParmPackExpr>(Val: E);
19621	// If any of the declarations in the pack is odr-used, then the expression
19622	// as a whole constitutes an odr-use.
19623	for (ValueDecl *D : *FPPE)
19624	if (IsPotentialResultOdrUsed(D))
19625	return ExprEmpty();
19626
19627	// FIXME: Rebuild as a non-odr-use FunctionParmPackExpr? In practice,
19628	// nothing cares about whether we marked this as an odr-use, but it might
19629	// be useful for non-compiler tools.
19630	MarkNotOdrUsed();
19631	break;
19632	}
19633
19634	// -- If e is a subscripting operation with an array operand...
19635	case Expr::ArraySubscriptExprClass: {
19636	auto *ASE = cast<ArraySubscriptExpr>(Val: E);
19637	Expr *OldBase = ASE->getBase()->IgnoreImplicit();
19638	if (!OldBase->getType()->isArrayType())
19639	break;
19640	ExprResult Base = Rebuild(OldBase);
19641	if (!Base.isUsable())
19642	return Base;
19643	Expr *LHS = ASE->getBase() == ASE->getLHS() ? Base.get() : ASE->getLHS();
19644	Expr *RHS = ASE->getBase() == ASE->getRHS() ? Base.get() : ASE->getRHS();
19645	SourceLocation LBracketLoc = ASE->getBeginLoc(); // FIXME: Not stored.
19646	return S.ActOnArraySubscriptExpr(S: nullptr, base: LHS, lbLoc: LBracketLoc, ArgExprs: RHS,
19647	rbLoc: ASE->getRBracketLoc());
19648	}
19649
19650	case Expr::MemberExprClass: {
19651	auto *ME = cast<MemberExpr>(Val: E);
19652	// -- If e is a class member access expression [...] naming a non-static
19653	// data member...
19654	if (isa<FieldDecl>(Val: ME->getMemberDecl())) {
19655	ExprResult Base = Rebuild(ME->getBase());
19656	if (!Base.isUsable())
19657	return Base;
19658	return MemberExpr::Create(
19659	C: S.Context, Base: Base.get(), IsArrow: ME->isArrow(), OperatorLoc: ME->getOperatorLoc(),
19660	QualifierLoc: ME->getQualifierLoc(), TemplateKWLoc: ME->getTemplateKeywordLoc(),
19661	MemberDecl: ME->getMemberDecl(), FoundDecl: ME->getFoundDecl(), MemberNameInfo: ME->getMemberNameInfo(),
19662	TemplateArgs: CopiedTemplateArgs(ME), T: ME->getType(), VK: ME->getValueKind(),
19663	OK: ME->getObjectKind(), NOUR: ME->isNonOdrUse());
19664	}
19665
19666	if (ME->getMemberDecl()->isCXXInstanceMember())
19667	break;
19668
19669	// -- If e is a class member access expression naming a static data member,
19670	// ...
19671	if (ME->isNonOdrUse() || IsPotentialResultOdrUsed(ME->getMemberDecl()))
19672	break;
19673
19674	// Rebuild as a non-odr-use MemberExpr.
19675	MarkNotOdrUsed();
19676	return MemberExpr::Create(
19677	C: S.Context, Base: ME->getBase(), IsArrow: ME->isArrow(), OperatorLoc: ME->getOperatorLoc(),
19678	QualifierLoc: ME->getQualifierLoc(), TemplateKWLoc: ME->getTemplateKeywordLoc(), MemberDecl: ME->getMemberDecl(),
19679	FoundDecl: ME->getFoundDecl(), MemberNameInfo: ME->getMemberNameInfo(), TemplateArgs: CopiedTemplateArgs(ME),
19680	T: ME->getType(), VK: ME->getValueKind(), OK: ME->getObjectKind(), NOUR);
19681	}
19682
19683	case Expr::BinaryOperatorClass: {
19684	auto *BO = cast<BinaryOperator>(Val: E);
19685	Expr *LHS = BO->getLHS();
19686	Expr *RHS = BO->getRHS();
19687	// -- If e is a pointer-to-member expression of the form e1 .* e2 ...
19688	if (BO->getOpcode() == BO_PtrMemD) {
19689	ExprResult Sub = Rebuild(LHS);
19690	if (!Sub.isUsable())
19691	return Sub;
19692	BO->setLHS(Sub.get());
19693	// -- If e is a comma expression, ...
19694	} else if (BO->getOpcode() == BO_Comma) {
19695	ExprResult Sub = Rebuild(RHS);
19696	if (!Sub.isUsable())
19697	return Sub;
19698	BO->setRHS(Sub.get());
19699	} else {
19700	break;
19701	}
19702	return ExprResult(BO);
19703	}
19704
19705	// -- If e has the form (e1)...
19706	case Expr::ParenExprClass: {
19707	auto *PE = cast<ParenExpr>(Val: E);
19708	ExprResult Sub = Rebuild(PE->getSubExpr());
19709	if (!Sub.isUsable())
19710	return Sub;
19711	return S.ActOnParenExpr(L: PE->getLParen(), R: PE->getRParen(), E: Sub.get());
19712	}
19713
19714	// -- If e is a glvalue conditional expression, ...
19715	// We don't apply this to a binary conditional operator. FIXME: Should we?
19716	case Expr::ConditionalOperatorClass: {
19717	auto *CO = cast<ConditionalOperator>(Val: E);
19718	ExprResult LHS = Rebuild(CO->getLHS());
19719	if (LHS.isInvalid())
19720	return ExprError();
19721	ExprResult RHS = Rebuild(CO->getRHS());
19722	if (RHS.isInvalid())
19723	return ExprError();
19724	if (!LHS.isUsable() && !RHS.isUsable())
19725	return ExprEmpty();
19726	if (!LHS.isUsable())
19727	LHS = CO->getLHS();
19728	if (!RHS.isUsable())
19729	RHS = CO->getRHS();
19730	return S.ActOnConditionalOp(QuestionLoc: CO->getQuestionLoc(), ColonLoc: CO->getColonLoc(),
19731	CondExpr: CO->getCond(), LHSExpr: LHS.get(), RHSExpr: RHS.get());
19732	}
19733
19734	// [Clang extension]
19735	// -- If e has the form __extension__ e1...
19736	case Expr::UnaryOperatorClass: {
19737	auto *UO = cast<UnaryOperator>(Val: E);
19738	if (UO->getOpcode() != UO_Extension)
19739	break;
19740	ExprResult Sub = Rebuild(UO->getSubExpr());
19741	if (!Sub.isUsable())
19742	return Sub;
19743	return S.BuildUnaryOp(S: nullptr, OpLoc: UO->getOperatorLoc(), Opc: UO_Extension,
19744	Input: Sub.get());
19745	}
19746
19747	// [Clang extension]
19748	// -- If e has the form _Generic(...), the set of potential results is the
19749	// union of the sets of potential results of the associated expressions.
19750	case Expr::GenericSelectionExprClass: {
19751	auto *GSE = cast<GenericSelectionExpr>(Val: E);
19752
19753	SmallVector<Expr *, 4> AssocExprs;
19754	bool AnyChanged = false;
19755	for (Expr *OrigAssocExpr : GSE->getAssocExprs()) {
19756	ExprResult AssocExpr = Rebuild(OrigAssocExpr);
19757	if (AssocExpr.isInvalid())
19758	return ExprError();
19759	if (AssocExpr.isUsable()) {
19760	AssocExprs.push_back(Elt: AssocExpr.get());
19761	AnyChanged = true;
19762	} else {
19763	AssocExprs.push_back(Elt: OrigAssocExpr);
19764	}
19765	}
19766
19767	void *ExOrTy = nullptr;
19768	bool IsExpr = GSE->isExprPredicate();
19769	if (IsExpr)
19770	ExOrTy = GSE->getControllingExpr();
19771	else
19772	ExOrTy = GSE->getControllingType();
19773	return AnyChanged ? S.CreateGenericSelectionExpr(
19774	KeyLoc: GSE->getGenericLoc(), DefaultLoc: GSE->getDefaultLoc(),
19775	RParenLoc: GSE->getRParenLoc(), PredicateIsExpr: IsExpr, ControllingExprOrType: ExOrTy,
19776	Types: GSE->getAssocTypeSourceInfos(), Exprs: AssocExprs)
19777	: ExprEmpty();
19778	}
19779
19780	// [Clang extension]
19781	// -- If e has the form __builtin_choose_expr(...), the set of potential
19782	// results is the union of the sets of potential results of the
19783	// second and third subexpressions.
19784	case Expr::ChooseExprClass: {
19785	auto *CE = cast<ChooseExpr>(Val: E);
19786
19787	ExprResult LHS = Rebuild(CE->getLHS());
19788	if (LHS.isInvalid())
19789	return ExprError();
19790
19791	ExprResult RHS = Rebuild(CE->getLHS());
19792	if (RHS.isInvalid())
19793	return ExprError();
19794
19795	if (!LHS.get() && !RHS.get())
19796	return ExprEmpty();
19797	if (!LHS.isUsable())
19798	LHS = CE->getLHS();
19799	if (!RHS.isUsable())
19800	RHS = CE->getRHS();
19801
19802	return S.ActOnChooseExpr(BuiltinLoc: CE->getBuiltinLoc(), CondExpr: CE->getCond(), LHSExpr: LHS.get(),
19803	RHSExpr: RHS.get(), RPLoc: CE->getRParenLoc());
19804	}
19805
19806	// Step through non-syntactic nodes.
19807	case Expr::ConstantExprClass: {
19808	auto *CE = cast<ConstantExpr>(Val: E);
19809	ExprResult Sub = Rebuild(CE->getSubExpr());
19810	if (!Sub.isUsable())
19811	return Sub;
19812	return ConstantExpr::Create(Context: S.Context, E: Sub.get());
19813	}
19814
19815	// We could mostly rely on the recursive rebuilding to rebuild implicit
19816	// casts, but not at the top level, so rebuild them here.
19817	case Expr::ImplicitCastExprClass: {
19818	auto *ICE = cast<ImplicitCastExpr>(Val: E);
19819	// Only step through the narrow set of cast kinds we expect to encounter.
19820	// Anything else suggests we've left the region in which potential results
19821	// can be found.
19822	switch (ICE->getCastKind()) {
19823	case CK_NoOp:
19824	case CK_DerivedToBase:
19825	case CK_UncheckedDerivedToBase: {
19826	ExprResult Sub = Rebuild(ICE->getSubExpr());
19827	if (!Sub.isUsable())
19828	return Sub;
19829	CXXCastPath Path(ICE->path());
19830	return S.ImpCastExprToType(E: Sub.get(), Type: ICE->getType(), CK: ICE->getCastKind(),
19831	VK: ICE->getValueKind(), BasePath: &Path);
19832	}
19833
19834	default:
19835	break;
19836	}
19837	break;
19838	}
19839
19840	default:
19841	break;
19842	}
19843
19844	// Can't traverse through this node. Nothing to do.
19845	return ExprEmpty();
19846	}
19847
19848	ExprResult Sema::CheckLValueToRValueConversionOperand(Expr *E) {
19849	// Check whether the operand is or contains an object of non-trivial C union
19850	// type.
19851	if (E->getType().isVolatileQualified() &&
19852	(E->getType().hasNonTrivialToPrimitiveDestructCUnion() ||
19853	E->getType().hasNonTrivialToPrimitiveCopyCUnion()))
19854	checkNonTrivialCUnion(QT: E->getType(), Loc: E->getExprLoc(),
19855	UseContext: NonTrivialCUnionContext::LValueToRValueVolatile,
19856	NonTrivialKind: NTCUK_Destruct | NTCUK_Copy);
19857
19858	// C++2a [basic.def.odr]p4:
19859	// [...] an expression of non-volatile-qualified non-class type to which
19860	// the lvalue-to-rvalue conversion is applied [...]
19861	if (E->getType().isVolatileQualified() || E->getType()->getAs<RecordType>())
19862	return E;
19863
19864	ExprResult Result =
19865	rebuildPotentialResultsAsNonOdrUsed(S&: *this, E, NOUR: NOUR_Constant);
19866	if (Result.isInvalid())
19867	return ExprError();
19868	return Result.get() ? Result : E;
19869	}
19870
19871	ExprResult Sema::ActOnConstantExpression(ExprResult Res) {
19872	if (!Res.isUsable())
19873	return Res;
19874
19875	// If a constant-expression is a reference to a variable where we delay
19876	// deciding whether it is an odr-use, just assume we will apply the
19877	// lvalue-to-rvalue conversion. In the one case where this doesn't happen
19878	// (a non-type template argument), we have special handling anyway.
19879	return CheckLValueToRValueConversionOperand(E: Res.get());
19880	}
19881
19882	void Sema::CleanupVarDeclMarking() {
19883	// Iterate through a local copy in case MarkVarDeclODRUsed makes a recursive
19884	// call.
19885	MaybeODRUseExprSet LocalMaybeODRUseExprs;
19886	std::swap(LHS&: LocalMaybeODRUseExprs, RHS&: MaybeODRUseExprs);
19887
19888	for (Expr *E : LocalMaybeODRUseExprs) {
19889	if (auto *DRE = dyn_cast<DeclRefExpr>(Val: E)) {
19890	MarkVarDeclODRUsed(V: cast<VarDecl>(Val: DRE->getDecl()),
19891	Loc: DRE->getLocation(), SemaRef&: *this);
19892	} else if (auto *ME = dyn_cast<MemberExpr>(Val: E)) {
19893	MarkVarDeclODRUsed(V: cast<VarDecl>(Val: ME->getMemberDecl()), Loc: ME->getMemberLoc(),
19894	SemaRef&: *this);
19895	} else if (auto *FP = dyn_cast<FunctionParmPackExpr>(Val: E)) {
19896	for (ValueDecl *VD : *FP)
19897	MarkVarDeclODRUsed(V: VD, Loc: FP->getParameterPackLocation(), SemaRef&: *this);
19898	} else {
19899	llvm_unreachable("Unexpected expression");
19900	}
19901	}
19902
19903	assert(MaybeODRUseExprs.empty() &&
19904	"MarkVarDeclODRUsed failed to cleanup MaybeODRUseExprs?");
19905	}
19906
19907	static void DoMarkPotentialCapture(Sema &SemaRef, SourceLocation Loc,
19908	ValueDecl *Var, Expr *E) {
19909	VarDecl *VD = Var->getPotentiallyDecomposedVarDecl();
19910	if (!VD)
19911	return;
19912
19913	const bool RefersToEnclosingScope =
19914	(SemaRef.CurContext != VD->getDeclContext() &&
19915	VD->getDeclContext()->isFunctionOrMethod() && VD->hasLocalStorage());
19916	if (RefersToEnclosingScope) {
19917	LambdaScopeInfo *const LSI =
19918	SemaRef.getCurLambda(/*IgnoreNonLambdaCapturingScope=*/true);
19919	if (LSI && (!LSI->CallOperator ||
19920	!LSI->CallOperator->Encloses(DC: Var->getDeclContext()))) {
19921	// If a variable could potentially be odr-used, defer marking it so
19922	// until we finish analyzing the full expression for any
19923	// lvalue-to-rvalue
19924	// or discarded value conversions that would obviate odr-use.
19925	// Add it to the list of potential captures that will be analyzed
19926	// later (ActOnFinishFullExpr) for eventual capture and odr-use marking
19927	// unless the variable is a reference that was initialized by a constant
19928	// expression (this will never need to be captured or odr-used).
19929	//
19930	// FIXME: We can simplify this a lot after implementing P0588R1.
19931	assert(E && "Capture variable should be used in an expression.");
19932	if (!Var->getType()->isReferenceType() ||
19933	!VD->isUsableInConstantExpressions(C: SemaRef.Context))
19934	LSI->addPotentialCapture(VarExpr: E->IgnoreParens());
19935	}
19936	}
19937	}
19938
19939	static void DoMarkVarDeclReferenced(
19940	Sema &SemaRef, SourceLocation Loc, VarDecl *Var, Expr *E,
19941	llvm::DenseMap<const VarDecl *, int> &RefsMinusAssignments) {
19942	assert((!E || isa<DeclRefExpr>(E) || isa<MemberExpr>(E) ||
19943	isa<FunctionParmPackExpr>(E)) &&
19944	"Invalid Expr argument to DoMarkVarDeclReferenced");
19945	Var->setReferenced();
19946
19947	if (Var->isInvalidDecl())
19948	return;
19949
19950	auto *MSI = Var->getMemberSpecializationInfo();
19951	TemplateSpecializationKind TSK = MSI ? MSI->getTemplateSpecializationKind()
19952	: Var->getTemplateSpecializationKind();
19953
19954	OdrUseContext OdrUse = isOdrUseContext(SemaRef);
19955	bool UsableInConstantExpr =
19956	Var->mightBeUsableInConstantExpressions(C: SemaRef.Context);
19957
19958	if (Var->isLocalVarDeclOrParm() && !Var->hasExternalStorage()) {
19959	RefsMinusAssignments.insert(KV: {Var, 0}).first->getSecond()++;
19960	}
19961
19962	// C++20 [expr.const]p12:
19963	// A variable [...] is needed for constant evaluation if it is [...] a
19964	// variable whose name appears as a potentially constant evaluated
19965	// expression that is either a contexpr variable or is of non-volatile
19966	// const-qualified integral type or of reference type
19967	bool NeededForConstantEvaluation =
19968	isPotentiallyConstantEvaluatedContext(SemaRef) && UsableInConstantExpr;
19969
19970	bool NeedDefinition =
19971	OdrUse == OdrUseContext::Used || NeededForConstantEvaluation;
19972
19973	assert(!isa<VarTemplatePartialSpecializationDecl>(Var) &&
19974	"Can't instantiate a partial template specialization.");
19975
19976	// If this might be a member specialization of a static data member, check
19977	// the specialization is visible. We already did the checks for variable
19978	// template specializations when we created them.
19979	if (NeedDefinition && TSK != TSK_Undeclared &&
19980	!isa<VarTemplateSpecializationDecl>(Val: Var))
19981	SemaRef.checkSpecializationVisibility(Loc, Spec: Var);
19982
19983	// Perform implicit instantiation of static data members, static data member
19984	// templates of class templates, and variable template specializations. Delay
19985	// instantiations of variable templates, except for those that could be used
19986	// in a constant expression.
19987	if (NeedDefinition && isTemplateInstantiation(Kind: TSK)) {
19988	// Per C++17 [temp.explicit]p10, we may instantiate despite an explicit
19989	// instantiation declaration if a variable is usable in a constant
19990	// expression (among other cases).
19991	bool TryInstantiating =
19992	TSK == TSK_ImplicitInstantiation ||
19993	(TSK == TSK_ExplicitInstantiationDeclaration && UsableInConstantExpr);
19994
19995	if (TryInstantiating) {
19996	SourceLocation PointOfInstantiation =
19997	MSI ? MSI->getPointOfInstantiation() : Var->getPointOfInstantiation();
19998	bool FirstInstantiation = PointOfInstantiation.isInvalid();
19999	if (FirstInstantiation) {
20000	PointOfInstantiation = Loc;
20001	if (MSI)
20002	MSI->setPointOfInstantiation(PointOfInstantiation);
20003	// FIXME: Notify listener.
20004	else
20005	Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
20006	}
20007
20008	if (UsableInConstantExpr || Var->getType()->isUndeducedType()) {
20009	// Do not defer instantiations of variables that could be used in a
20010	// constant expression.
20011	// The type deduction also needs a complete initializer.
20012	SemaRef.runWithSufficientStackSpace(Loc: PointOfInstantiation, Fn: [&] {
20013	SemaRef.InstantiateVariableDefinition(PointOfInstantiation, Var);
20014	});
20015
20016	// The size of an incomplete array type can be updated by
20017	// instantiating the initializer. The DeclRefExpr's type should be
20018	// updated accordingly too, or users of it would be confused!
20019	if (E)
20020	SemaRef.getCompletedType(E);
20021
20022	// Re-set the member to trigger a recomputation of the dependence bits
20023	// for the expression.
20024	if (auto *DRE = dyn_cast_or_null<DeclRefExpr>(Val: E))
20025	DRE->setDecl(DRE->getDecl());
20026	else if (auto *ME = dyn_cast_or_null<MemberExpr>(Val: E))
20027	ME->setMemberDecl(ME->getMemberDecl());
20028	} else if (FirstInstantiation) {
20029	SemaRef.PendingInstantiations
20030	.push_back(x: std::make_pair(x&: Var, y&: PointOfInstantiation));
20031	} else {
20032	bool Inserted = false;
20033	for (auto &I : SemaRef.SavedPendingInstantiations) {
20034	auto Iter = llvm::find_if(
20035	Range&: I, P: [Var](const Sema::PendingImplicitInstantiation &P) {
20036	return P.first == Var;
20037	});
20038	if (Iter != I.end()) {
20039	SemaRef.PendingInstantiations.push_back(x: *Iter);
20040	I.erase(position: Iter);
20041	Inserted = true;
20042	break;
20043	}
20044	}
20045
20046	// FIXME: For a specialization of a variable template, we don't
20047	// distinguish between "declaration and type implicitly instantiated"
20048	// and "implicit instantiation of definition requested", so we have
20049	// no direct way to avoid enqueueing the pending instantiation
20050	// multiple times.
20051	if (isa<VarTemplateSpecializationDecl>(Val: Var) && !Inserted)
20052	SemaRef.PendingInstantiations
20053	.push_back(x: std::make_pair(x&: Var, y&: PointOfInstantiation));
20054	}
20055	}
20056	}
20057
20058	// C++2a [basic.def.odr]p4:
20059	// A variable x whose name appears as a potentially-evaluated expression e
20060	// is odr-used by e unless
20061	// -- x is a reference that is usable in constant expressions
20062	// -- x is a variable of non-reference type that is usable in constant
20063	// expressions and has no mutable subobjects [FIXME], and e is an
20064	// element of the set of potential results of an expression of
20065	// non-volatile-qualified non-class type to which the lvalue-to-rvalue
20066	// conversion is applied
20067	// -- x is a variable of non-reference type, and e is an element of the set
20068	// of potential results of a discarded-value expression to which the
20069	// lvalue-to-rvalue conversion is not applied [FIXME]
20070	//
20071	// We check the first part of the second bullet here, and
20072	// Sema::CheckLValueToRValueConversionOperand deals with the second part.
20073	// FIXME: To get the third bullet right, we need to delay this even for
20074	// variables that are not usable in constant expressions.
20075
20076	// If we already know this isn't an odr-use, there's nothing more to do.
20077	if (DeclRefExpr *DRE = dyn_cast_or_null<DeclRefExpr>(Val: E))
20078	if (DRE->isNonOdrUse())
20079	return;
20080	if (MemberExpr *ME = dyn_cast_or_null<MemberExpr>(Val: E))
20081	if (ME->isNonOdrUse())
20082	return;
20083
20084	switch (OdrUse) {
20085	case OdrUseContext::None:
20086	// In some cases, a variable may not have been marked unevaluated, if it
20087	// appears in a defaukt initializer.
20088	assert((!E || isa<FunctionParmPackExpr>(E) ||
20089	SemaRef.isUnevaluatedContext()) &&
20090	"missing non-odr-use marking for unevaluated decl ref");
20091	break;
20092
20093	case OdrUseContext::FormallyOdrUsed:
20094	// FIXME: Ignoring formal odr-uses results in incorrect lambda capture
20095	// behavior.
20096	break;
20097
20098	case OdrUseContext::Used:
20099	// If we might later find that this expression isn't actually an odr-use,
20100	// delay the marking.
20101	if (E && Var->isUsableInConstantExpressions(C: SemaRef.Context))
20102	SemaRef.MaybeODRUseExprs.insert(X: E);
20103	else
20104	MarkVarDeclODRUsed(V: Var, Loc, SemaRef);
20105	break;
20106
20107	case OdrUseContext::Dependent:
20108	// If this is a dependent context, we don't need to mark variables as
20109	// odr-used, but we may still need to track them for lambda capture.
20110	// FIXME: Do we also need to do this inside dependent typeid expressions
20111	// (which are modeled as unevaluated at this point)?
20112	DoMarkPotentialCapture(SemaRef, Loc, Var, E);
20113	break;
20114	}
20115	}
20116
20117	static void DoMarkBindingDeclReferenced(Sema &SemaRef, SourceLocation Loc,
20118	BindingDecl *BD, Expr *E) {
20119	BD->setReferenced();
20120
20121	if (BD->isInvalidDecl())
20122	return;
20123
20124	OdrUseContext OdrUse = isOdrUseContext(SemaRef);
20125	if (OdrUse == OdrUseContext::Used) {
20126	QualType CaptureType, DeclRefType;
20127	SemaRef.tryCaptureVariable(Var: BD, ExprLoc: Loc, Kind: TryCaptureKind::Implicit,
20128	/*EllipsisLoc*/ SourceLocation(),
20129	/*BuildAndDiagnose*/ true, CaptureType,
20130	DeclRefType,
20131	/*FunctionScopeIndexToStopAt*/ nullptr);
20132	} else if (OdrUse == OdrUseContext::Dependent) {
20133	DoMarkPotentialCapture(SemaRef, Loc, Var: BD, E);
20134	}
20135	}
20136
20137	void Sema::MarkVariableReferenced(SourceLocation Loc, VarDecl *Var) {
20138	DoMarkVarDeclReferenced(SemaRef&: *this, Loc, Var, E: nullptr, RefsMinusAssignments);
20139	}
20140
20141	// C++ [temp.dep.expr]p3:
20142	// An id-expression is type-dependent if it contains:
20143	// - an identifier associated by name lookup with an entity captured by copy
20144	// in a lambda-expression that has an explicit object parameter whose type
20145	// is dependent ([dcl.fct]),
20146	static void FixDependencyOfIdExpressionsInLambdaWithDependentObjectParameter(
20147	Sema &SemaRef, ValueDecl *D, Expr *E) {
20148	auto *ID = dyn_cast<DeclRefExpr>(Val: E);
20149	if (!ID || ID->isTypeDependent() || !ID->refersToEnclosingVariableOrCapture())
20150	return;
20151
20152	// If any enclosing lambda with a dependent explicit object parameter either
20153	// explicitly captures the variable by value, or has a capture default of '='
20154	// and does not capture the variable by reference, then the type of the DRE
20155	// is dependent on the type of that lambda's explicit object parameter.
20156	auto IsDependent = [&]() {
20157	for (auto *Scope : llvm::reverse(C&: SemaRef.FunctionScopes)) {
20158	auto *LSI = dyn_cast<sema::LambdaScopeInfo>(Val: Scope);
20159	if (!LSI)
20160	continue;
20161
20162	if (LSI->Lambda && !LSI->Lambda->Encloses(DC: SemaRef.CurContext) &&
20163	LSI->AfterParameterList)
20164	return false;
20165
20166	const auto *MD = LSI->CallOperator;
20167	if (MD->getType().isNull())
20168	continue;
20169
20170	const auto *Ty = MD->getType()->getAs<FunctionProtoType>();
20171	if (!Ty || !MD->isExplicitObjectMemberFunction() ||
20172	!Ty->getParamType(i: 0)->isDependentType())
20173	continue;
20174
20175	if (auto *C = LSI->CaptureMap.count(Val: D) ? &LSI->getCapture(Var: D) : nullptr) {
20176	if (C->isCopyCapture())
20177	return true;
20178	continue;
20179	}
20180
20181	if (LSI->ImpCaptureStyle == LambdaScopeInfo::ImpCap_LambdaByval)
20182	return true;
20183	}
20184	return false;
20185	}();
20186
20187	ID->setCapturedByCopyInLambdaWithExplicitObjectParameter(
20188	Set: IsDependent, Context: SemaRef.getASTContext());
20189	}
20190
20191	static void
20192	MarkExprReferenced(Sema &SemaRef, SourceLocation Loc, Decl *D, Expr *E,
20193	bool MightBeOdrUse,
20194	llvm::DenseMap<const VarDecl *, int> &RefsMinusAssignments) {
20195	if (SemaRef.OpenMP().isInOpenMPDeclareTargetContext())
20196	SemaRef.OpenMP().checkDeclIsAllowedInOpenMPTarget(E, D);
20197
20198	if (SemaRef.getLangOpts().OpenACC)
20199	SemaRef.OpenACC().CheckDeclReference(Loc, E, D);
20200
20201	if (VarDecl *Var = dyn_cast<VarDecl>(Val: D)) {
20202	DoMarkVarDeclReferenced(SemaRef, Loc, Var, E, RefsMinusAssignments);
20203	if (SemaRef.getLangOpts().CPlusPlus)
20204	FixDependencyOfIdExpressionsInLambdaWithDependentObjectParameter(SemaRef,
20205	D: Var, E);
20206	return;
20207	}
20208
20209	if (BindingDecl *Decl = dyn_cast<BindingDecl>(Val: D)) {
20210	DoMarkBindingDeclReferenced(SemaRef, Loc, BD: Decl, E);
20211	if (SemaRef.getLangOpts().CPlusPlus)
20212	FixDependencyOfIdExpressionsInLambdaWithDependentObjectParameter(SemaRef,
20213	D: Decl, E);
20214	return;
20215	}
20216	SemaRef.MarkAnyDeclReferenced(Loc, D, MightBeOdrUse);
20217
20218	// If this is a call to a method via a cast, also mark the method in the
20219	// derived class used in case codegen can devirtualize the call.
20220	const MemberExpr *ME = dyn_cast<MemberExpr>(Val: E);
20221	if (!ME)
20222	return;
20223	CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Val: ME->getMemberDecl());
20224	if (!MD)
20225	return;
20226	// Only attempt to devirtualize if this is truly a virtual call.
20227	bool IsVirtualCall = MD->isVirtual() &&
20228	ME->performsVirtualDispatch(LO: SemaRef.getLangOpts());
20229	if (!IsVirtualCall)
20230	return;
20231
20232	// If it's possible to devirtualize the call, mark the called function
20233	// referenced.
20234	CXXMethodDecl *DM = MD->getDevirtualizedMethod(
20235	Base: ME->getBase(), IsAppleKext: SemaRef.getLangOpts().AppleKext);
20236	if (DM)
20237	SemaRef.MarkAnyDeclReferenced(Loc, D: DM, MightBeOdrUse);
20238	}
20239
20240	void Sema::MarkDeclRefReferenced(DeclRefExpr *E, const Expr *Base) {
20241	// [basic.def.odr] (CWG 1614)
20242	// A function is named by an expression or conversion [...]
20243	// unless it is a pure virtual function and either the expression is not an
20244	// id-expression naming the function with an explicitly qualified name or
20245	// the expression forms a pointer to member
20246	bool OdrUse = true;
20247	if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Val: E->getDecl()))
20248	if (Method->isVirtual() &&
20249	!Method->getDevirtualizedMethod(Base, IsAppleKext: getLangOpts().AppleKext))
20250	OdrUse = false;
20251
20252	if (auto *FD = dyn_cast<FunctionDecl>(Val: E->getDecl())) {
20253	if (!isUnevaluatedContext() && !isConstantEvaluatedContext() &&
20254	!isImmediateFunctionContext() &&
20255	!isCheckingDefaultArgumentOrInitializer() &&
20256	FD->isImmediateFunction() && !RebuildingImmediateInvocation &&
20257	!FD->isDependentContext())
20258	ExprEvalContexts.back().ReferenceToConsteval.insert(Ptr: E);
20259	}
20260	MarkExprReferenced(SemaRef&: *this, Loc: E->getLocation(), D: E->getDecl(), E, MightBeOdrUse: OdrUse,
20261	RefsMinusAssignments);
20262	}
20263
20264	void Sema::MarkMemberReferenced(MemberExpr *E) {
20265	// C++11 [basic.def.odr]p2:
20266	// A non-overloaded function whose name appears as a potentially-evaluated
20267	// expression or a member of a set of candidate functions, if selected by
20268	// overload resolution when referred to from a potentially-evaluated
20269	// expression, is odr-used, unless it is a pure virtual function and its
20270	// name is not explicitly qualified.
20271	bool MightBeOdrUse = true;
20272	if (E->performsVirtualDispatch(LO: getLangOpts())) {
20273	if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Val: E->getMemberDecl()))
20274	if (Method->isPureVirtual())
20275	MightBeOdrUse = false;
20276	}
20277	SourceLocation Loc =
20278	E->getMemberLoc().isValid() ? E->getMemberLoc() : E->getBeginLoc();
20279	MarkExprReferenced(SemaRef&: *this, Loc, D: E->getMemberDecl(), E, MightBeOdrUse,
20280	RefsMinusAssignments);
20281	}
20282
20283	void Sema::MarkFunctionParmPackReferenced(FunctionParmPackExpr *E) {
20284	for (ValueDecl *VD : *E)
20285	MarkExprReferenced(SemaRef&: *this, Loc: E->getParameterPackLocation(), D: VD, E, MightBeOdrUse: true,
20286	RefsMinusAssignments);
20287	}
20288
20289	/// Perform marking for a reference to an arbitrary declaration. It
20290	/// marks the declaration referenced, and performs odr-use checking for
20291	/// functions and variables. This method should not be used when building a
20292	/// normal expression which refers to a variable.
20293	void Sema::MarkAnyDeclReferenced(SourceLocation Loc, Decl *D,
20294	bool MightBeOdrUse) {
20295	if (MightBeOdrUse) {
20296	if (auto *VD = dyn_cast<VarDecl>(Val: D)) {
20297	MarkVariableReferenced(Loc, Var: VD);
20298	return;
20299	}
20300	}
20301	if (auto *FD = dyn_cast<FunctionDecl>(Val: D)) {
20302	MarkFunctionReferenced(Loc, Func: FD, MightBeOdrUse);
20303	return;
20304	}
20305	D->setReferenced();
20306	}
20307
20308	namespace {
20309	// Mark all of the declarations used by a type as referenced.
20310	// FIXME: Not fully implemented yet! We need to have a better understanding
20311	// of when we're entering a context we should not recurse into.
20312	// FIXME: This is and EvaluatedExprMarker are more-or-less equivalent to
20313	// TreeTransforms rebuilding the type in a new context. Rather than
20314	// duplicating the TreeTransform logic, we should consider reusing it here.
20315	// Currently that causes problems when rebuilding LambdaExprs.
20316	class MarkReferencedDecls : public DynamicRecursiveASTVisitor {
20317	Sema &S;
20318	SourceLocation Loc;
20319
20320	public:
20321	MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) {}
20322
20323	bool TraverseTemplateArgument(const TemplateArgument &Arg) override;
20324	};
20325	}
20326
20327	bool MarkReferencedDecls::TraverseTemplateArgument(
20328	const TemplateArgument &Arg) {
20329	{
20330	// A non-type template argument is a constant-evaluated context.
20331	EnterExpressionEvaluationContext Evaluated(
20332	S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
20333	if (Arg.getKind() == TemplateArgument::Declaration) {
20334	if (Decl *D = Arg.getAsDecl())
20335	S.MarkAnyDeclReferenced(Loc, D, MightBeOdrUse: true);
20336	} else if (Arg.getKind() == TemplateArgument::Expression) {
20337	S.MarkDeclarationsReferencedInExpr(E: Arg.getAsExpr(), SkipLocalVariables: false);
20338	}
20339	}
20340
20341	return DynamicRecursiveASTVisitor::TraverseTemplateArgument(Arg);
20342	}
20343
20344	void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) {
20345	MarkReferencedDecls Marker(*this, Loc);
20346	Marker.TraverseType(T);
20347	}
20348
20349	namespace {
20350	/// Helper class that marks all of the declarations referenced by
20351	/// potentially-evaluated subexpressions as "referenced".
20352	class EvaluatedExprMarker : public UsedDeclVisitor<EvaluatedExprMarker> {
20353	public:
20354	typedef UsedDeclVisitor<EvaluatedExprMarker> Inherited;
20355	bool SkipLocalVariables;
20356	ArrayRef<const Expr *> StopAt;
20357
20358	EvaluatedExprMarker(Sema &S, bool SkipLocalVariables,
20359	ArrayRef<const Expr *> StopAt)
20360	: Inherited(S), SkipLocalVariables(SkipLocalVariables), StopAt(StopAt) {}
20361
20362	void visitUsedDecl(SourceLocation Loc, Decl *D) {
20363	S.MarkFunctionReferenced(Loc, Func: cast<FunctionDecl>(Val: D));
20364	}
20365
20366	void Visit(Expr *E) {
20367	if (llvm::is_contained(Range&: StopAt, Element: E))
20368	return;
20369	Inherited::Visit(S: E);
20370	}
20371
20372	void VisitConstantExpr(ConstantExpr *E) {
20373	// Don't mark declarations within a ConstantExpression, as this expression
20374	// will be evaluated and folded to a value.
20375	}
20376
20377	void VisitDeclRefExpr(DeclRefExpr *E) {
20378	// If we were asked not to visit local variables, don't.
20379	if (SkipLocalVariables) {
20380	if (VarDecl *VD = dyn_cast<VarDecl>(Val: E->getDecl()))
20381	if (VD->hasLocalStorage())
20382	return;
20383	}
20384
20385	// FIXME: This can trigger the instantiation of the initializer of a
20386	// variable, which can cause the expression to become value-dependent
20387	// or error-dependent. Do we need to propagate the new dependence bits?
20388	S.MarkDeclRefReferenced(E);
20389	}
20390
20391	void VisitMemberExpr(MemberExpr *E) {
20392	S.MarkMemberReferenced(E);
20393	Visit(E: E->getBase());
20394	}
20395	};
20396	} // namespace
20397
20398	void Sema::MarkDeclarationsReferencedInExpr(Expr *E,
20399	bool SkipLocalVariables,
20400	ArrayRef<const Expr*> StopAt) {
20401	EvaluatedExprMarker(*this, SkipLocalVariables, StopAt).Visit(E);
20402	}
20403
20404	/// Emit a diagnostic when statements are reachable.
20405	/// FIXME: check for reachability even in expressions for which we don't build a
20406	/// CFG (eg, in the initializer of a global or in a constant expression).
20407	/// For example,
20408	/// namespace { auto *p = new double[3][false ? (1, 2) : 3]; }
20409	bool Sema::DiagIfReachable(SourceLocation Loc, ArrayRef<const Stmt *> Stmts,
20410	const PartialDiagnostic &PD) {
20411	if (!Stmts.empty() && getCurFunctionOrMethodDecl()) {
20412	if (!FunctionScopes.empty())
20413	FunctionScopes.back()->PossiblyUnreachableDiags.push_back(
20414	Elt: sema::PossiblyUnreachableDiag(PD, Loc, Stmts));
20415	return true;
20416	}
20417
20418	// The initializer of a constexpr variable or of the first declaration of a
20419	// static data member is not syntactically a constant evaluated constant,
20420	// but nonetheless is always required to be a constant expression, so we
20421	// can skip diagnosing.
20422	// FIXME: Using the mangling context here is a hack.
20423	if (auto *VD = dyn_cast_or_null<VarDecl>(
20424	Val: ExprEvalContexts.back().ManglingContextDecl)) {
20425	if (VD->isConstexpr() ||
20426	(VD->isStaticDataMember() && VD->isFirstDecl() && !VD->isInline()))
20427	return false;
20428	// FIXME: For any other kind of variable, we should build a CFG for its
20429	// initializer and check whether the context in question is reachable.
20430	}
20431
20432	Diag(Loc, PD);
20433	return true;
20434	}
20435
20436	/// Emit a diagnostic that describes an effect on the run-time behavior
20437	/// of the program being compiled.
20438	///
20439	/// This routine emits the given diagnostic when the code currently being
20440	/// type-checked is "potentially evaluated", meaning that there is a
20441	/// possibility that the code will actually be executable. Code in sizeof()
20442	/// expressions, code used only during overload resolution, etc., are not
20443	/// potentially evaluated. This routine will suppress such diagnostics or,
20444	/// in the absolutely nutty case of potentially potentially evaluated
20445	/// expressions (C++ typeid), queue the diagnostic to potentially emit it
20446	/// later.
20447	///
20448	/// This routine should be used for all diagnostics that describe the run-time
20449	/// behavior of a program, such as passing a non-POD value through an ellipsis.
20450	/// Failure to do so will likely result in spurious diagnostics or failures
20451	/// during overload resolution or within sizeof/alignof/typeof/typeid.
20452	bool Sema::DiagRuntimeBehavior(SourceLocation Loc, ArrayRef<const Stmt*> Stmts,
20453	const PartialDiagnostic &PD) {
20454
20455	if (ExprEvalContexts.back().isDiscardedStatementContext())
20456	return false;
20457
20458	switch (ExprEvalContexts.back().Context) {
20459	case ExpressionEvaluationContext::Unevaluated:
20460	case ExpressionEvaluationContext::UnevaluatedList:
20461	case ExpressionEvaluationContext::UnevaluatedAbstract:
20462	case ExpressionEvaluationContext::DiscardedStatement:
20463	// The argument will never be evaluated, so don't complain.
20464	break;
20465
20466	case ExpressionEvaluationContext::ConstantEvaluated:
20467	case ExpressionEvaluationContext::ImmediateFunctionContext:
20468	// Relevant diagnostics should be produced by constant evaluation.
20469	break;
20470
20471	case ExpressionEvaluationContext::PotentiallyEvaluated:
20472	case ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
20473	return DiagIfReachable(Loc, Stmts, PD);
20474	}
20475
20476	return false;
20477	}
20478
20479	bool Sema::DiagRuntimeBehavior(SourceLocation Loc, const Stmt *Statement,
20480	const PartialDiagnostic &PD) {
20481	return DiagRuntimeBehavior(
20482	Loc, Stmts: Statement ? llvm::ArrayRef(Statement) : llvm::ArrayRef<Stmt *>(),
20483	PD);
20484	}
20485
20486	bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc,
20487	CallExpr *CE, FunctionDecl *FD) {
20488	if (ReturnType->isVoidType() || !ReturnType->isIncompleteType())
20489	return false;
20490
20491	// If we're inside a decltype's expression, don't check for a valid return
20492	// type or construct temporaries until we know whether this is the last call.
20493	if (ExprEvalContexts.back().ExprContext ==
20494	ExpressionEvaluationContextRecord::EK_Decltype) {
20495	ExprEvalContexts.back().DelayedDecltypeCalls.push_back(Elt: CE);
20496	return false;
20497	}
20498
20499	class CallReturnIncompleteDiagnoser : public TypeDiagnoser {
20500	FunctionDecl *FD;
20501	CallExpr *CE;
20502
20503	public:
20504	CallReturnIncompleteDiagnoser(FunctionDecl *FD, CallExpr *CE)
20505	: FD(FD), CE(CE) { }
20506
20507	void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
20508	if (!FD) {
20509	S.Diag(Loc, DiagID: diag::err_call_incomplete_return)
20510	<< T << CE->getSourceRange();
20511	return;
20512	}
20513
20514	S.Diag(Loc, DiagID: diag::err_call_function_incomplete_return)
20515	<< CE->getSourceRange() << FD << T;
20516	S.Diag(Loc: FD->getLocation(), DiagID: diag::note_entity_declared_at)
20517	<< FD->getDeclName();
20518	}
20519	} Diagnoser(FD, CE);
20520
20521	if (RequireCompleteType(Loc, T: ReturnType, Diagnoser))
20522	return true;
20523
20524	return false;
20525	}
20526
20527	// Diagnose the s/=/==/ and s/\|=/!=/ typos. Note that adding parentheses
20528	// will prevent this condition from triggering, which is what we want.
20529	void Sema::DiagnoseAssignmentAsCondition(Expr *E) {
20530	SourceLocation Loc;
20531
20532	unsigned diagnostic = diag::warn_condition_is_assignment;
20533	bool IsOrAssign = false;
20534
20535	if (BinaryOperator *Op = dyn_cast<BinaryOperator>(Val: E)) {
20536	if (Op->getOpcode() != BO_Assign && Op->getOpcode() != BO_OrAssign)
20537	return;
20538
20539	IsOrAssign = Op->getOpcode() == BO_OrAssign;
20540
20541	// Greylist some idioms by putting them into a warning subcategory.
20542	if (ObjCMessageExpr *ME
20543	= dyn_cast<ObjCMessageExpr>(Val: Op->getRHS()->IgnoreParenCasts())) {
20544	Selector Sel = ME->getSelector();
20545
20546	// self = [<foo> init...]
20547	if (ObjC().isSelfExpr(RExpr: Op->getLHS()) && ME->getMethodFamily() == OMF_init)
20548	diagnostic = diag::warn_condition_is_idiomatic_assignment;
20549
20550	// <foo> = [<bar> nextObject]
20551	else if (Sel.isUnarySelector() && Sel.getNameForSlot(argIndex: 0) == "nextObject")
20552	diagnostic = diag::warn_condition_is_idiomatic_assignment;
20553	}
20554
20555	Loc = Op->getOperatorLoc();
20556	} else if (CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(Val: E)) {
20557	if (Op->getOperator() != OO_Equal && Op->getOperator() != OO_PipeEqual)
20558	return;
20559
20560	IsOrAssign = Op->getOperator() == OO_PipeEqual;
20561	Loc = Op->getOperatorLoc();
20562	} else if (PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(Val: E))
20563	return DiagnoseAssignmentAsCondition(E: POE->getSyntacticForm());
20564	else {
20565	// Not an assignment.
20566	return;
20567	}
20568
20569	Diag(Loc, DiagID: diagnostic) << E->getSourceRange();
20570
20571	SourceLocation Open = E->getBeginLoc();
20572	SourceLocation Close = getLocForEndOfToken(Loc: E->getSourceRange().getEnd());
20573	Diag(Loc, DiagID: diag::note_condition_assign_silence)
20574	<< FixItHint::CreateInsertion(InsertionLoc: Open, Code: "(")
20575	<< FixItHint::CreateInsertion(InsertionLoc: Close, Code: ")");
20576
20577	if (IsOrAssign)
20578	Diag(Loc, DiagID: diag::note_condition_or_assign_to_comparison)
20579	<< FixItHint::CreateReplacement(RemoveRange: Loc, Code: "!=");
20580	else
20581	Diag(Loc, DiagID: diag::note_condition_assign_to_comparison)
20582	<< FixItHint::CreateReplacement(RemoveRange: Loc, Code: "==");
20583	}
20584
20585	void Sema::DiagnoseEqualityWithExtraParens(ParenExpr *ParenE) {
20586	// Don't warn if the parens came from a macro.
20587	SourceLocation parenLoc = ParenE->getBeginLoc();
20588	if (parenLoc.isInvalid() || parenLoc.isMacroID())
20589	return;
20590	// Don't warn for dependent expressions.
20591	if (ParenE->isTypeDependent())
20592	return;
20593
20594	Expr *E = ParenE->IgnoreParens();
20595	if (ParenE->isProducedByFoldExpansion() && ParenE->getSubExpr() == E)
20596	return;
20597
20598	if (BinaryOperator *opE = dyn_cast<BinaryOperator>(Val: E))
20599	if (opE->getOpcode() == BO_EQ &&
20600	opE->getLHS()->IgnoreParenImpCasts()->isModifiableLvalue(Ctx&: Context)
20601	== Expr::MLV_Valid) {
20602	SourceLocation Loc = opE->getOperatorLoc();
20603
20604	Diag(Loc, DiagID: diag::warn_equality_with_extra_parens) << E->getSourceRange();
20605	SourceRange ParenERange = ParenE->getSourceRange();
20606	Diag(Loc, DiagID: diag::note_equality_comparison_silence)
20607	<< FixItHint::CreateRemoval(RemoveRange: ParenERange.getBegin())
20608	<< FixItHint::CreateRemoval(RemoveRange: ParenERange.getEnd());
20609	Diag(Loc, DiagID: diag::note_equality_comparison_to_assign)
20610	<< FixItHint::CreateReplacement(RemoveRange: Loc, Code: "=");
20611	}
20612	}
20613
20614	ExprResult Sema::CheckBooleanCondition(SourceLocation Loc, Expr *E,
20615	bool IsConstexpr) {
20616	DiagnoseAssignmentAsCondition(E);
20617	if (ParenExpr *parenE = dyn_cast<ParenExpr>(Val: E))
20618	DiagnoseEqualityWithExtraParens(ParenE: parenE);
20619
20620	ExprResult result = CheckPlaceholderExpr(E);
20621	if (result.isInvalid()) return ExprError();
20622	E = result.get();
20623
20624	if (!E->isTypeDependent()) {
20625	if (getLangOpts().CPlusPlus)
20626	return CheckCXXBooleanCondition(CondExpr: E, IsConstexpr); // C++ 6.4p4
20627
20628	ExprResult ERes = DefaultFunctionArrayLvalueConversion(E);
20629	if (ERes.isInvalid())
20630	return ExprError();
20631	E = ERes.get();
20632
20633	QualType T = E->getType();
20634	if (!T->isScalarType()) { // C99 6.8.4.1p1
20635	Diag(Loc, DiagID: diag::err_typecheck_statement_requires_scalar)
20636	<< T << E->getSourceRange();
20637	return ExprError();
20638	}
20639	CheckBoolLikeConversion(E, CC: Loc);
20640	}
20641
20642	return E;
20643	}
20644
20645	Sema::ConditionResult Sema::ActOnCondition(Scope *S, SourceLocation Loc,
20646	Expr *SubExpr, ConditionKind CK,
20647	bool MissingOK) {
20648	// MissingOK indicates whether having no condition expression is valid
20649	// (for loop) or invalid (e.g. while loop).
20650	if (!SubExpr)
20651	return MissingOK ? ConditionResult() : ConditionError();
20652
20653	ExprResult Cond;
20654	switch (CK) {
20655	case ConditionKind::Boolean:
20656	Cond = CheckBooleanCondition(Loc, E: SubExpr);
20657	break;
20658
20659	case ConditionKind::ConstexprIf:
20660	// Note: this might produce a FullExpr
20661	Cond = CheckBooleanCondition(Loc, E: SubExpr, IsConstexpr: true);
20662	break;
20663
20664	case ConditionKind::Switch:
20665	Cond = CheckSwitchCondition(SwitchLoc: Loc, Cond: SubExpr);
20666	break;
20667	}
20668	if (Cond.isInvalid()) {
20669	Cond = CreateRecoveryExpr(Begin: SubExpr->getBeginLoc(), End: SubExpr->getEndLoc(),
20670	SubExprs: {SubExpr}, T: PreferredConditionType(K: CK));
20671	if (!Cond.get())
20672	return ConditionError();
20673	} else if (Cond.isUsable() && !isa<FullExpr>(Val: Cond.get()))
20674	Cond = ActOnFinishFullExpr(Expr: Cond.get(), CC: Loc, /*DiscardedValue*/ false);
20675
20676	if (!Cond.isUsable())
20677	return ConditionError();
20678
20679	return ConditionResult(*this, nullptr, Cond,
20680	CK == ConditionKind::ConstexprIf);
20681	}
20682
20683	namespace {
20684	/// A visitor for rebuilding a call to an __unknown_any expression
20685	/// to have an appropriate type.
20686	struct RebuildUnknownAnyFunction
20687	: StmtVisitor<RebuildUnknownAnyFunction, ExprResult> {
20688
20689	Sema &S;
20690
20691	RebuildUnknownAnyFunction(Sema &S) : S(S) {}
20692
20693	ExprResult VisitStmt(Stmt *S) {
20694	llvm_unreachable("unexpected statement!");
20695	}
20696
20697	ExprResult VisitExpr(Expr *E) {
20698	S.Diag(Loc: E->getExprLoc(), DiagID: diag::err_unsupported_unknown_any_call)
20699	<< E->getSourceRange();
20700	return ExprError();
20701	}
20702
20703	/// Rebuild an expression which simply semantically wraps another
20704	/// expression which it shares the type and value kind of.
20705	template <class T> ExprResult rebuildSugarExpr(T *E) {
20706	ExprResult SubResult = Visit(S: E->getSubExpr());
20707	if (SubResult.isInvalid()) return ExprError();
20708
20709	Expr *SubExpr = SubResult.get();
20710	E->setSubExpr(SubExpr);
20711	E->setType(SubExpr->getType());
20712	E->setValueKind(SubExpr->getValueKind());
20713	assert(E->getObjectKind() == OK_Ordinary);
20714	return E;
20715	}
20716
20717	ExprResult VisitParenExpr(ParenExpr *E) {
20718	return rebuildSugarExpr(E);
20719	}
20720
20721	ExprResult VisitUnaryExtension(UnaryOperator *E) {
20722	return rebuildSugarExpr(E);
20723	}
20724
20725	ExprResult VisitUnaryAddrOf(UnaryOperator *E) {
20726	ExprResult SubResult = Visit(S: E->getSubExpr());
20727	if (SubResult.isInvalid()) return ExprError();
20728
20729	Expr *SubExpr = SubResult.get();
20730	E->setSubExpr(SubExpr);
20731	E->setType(S.Context.getPointerType(T: SubExpr->getType()));
20732	assert(E->isPRValue());
20733	assert(E->getObjectKind() == OK_Ordinary);
20734	return E;
20735	}
20736
20737	ExprResult resolveDecl(Expr *E, ValueDecl *VD) {
20738	if (!isa<FunctionDecl>(Val: VD)) return VisitExpr(E);
20739
20740	E->setType(VD->getType());
20741
20742	assert(E->isPRValue());
20743	if (S.getLangOpts().CPlusPlus &&
20744	!(isa<CXXMethodDecl>(Val: VD) &&
20745	cast<CXXMethodDecl>(Val: VD)->isInstance()))
20746	E->setValueKind(VK_LValue);
20747
20748	return E;
20749	}
20750
20751	ExprResult VisitMemberExpr(MemberExpr *E) {
20752	return resolveDecl(E, VD: E->getMemberDecl());
20753	}
20754
20755	ExprResult VisitDeclRefExpr(DeclRefExpr *E) {
20756	return resolveDecl(E, VD: E->getDecl());
20757	}
20758	};
20759	}
20760
20761	/// Given a function expression of unknown-any type, try to rebuild it
20762	/// to have a function type.
20763	static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *FunctionExpr) {
20764	ExprResult Result = RebuildUnknownAnyFunction(S).Visit(S: FunctionExpr);
20765	if (Result.isInvalid()) return ExprError();
20766	return S.DefaultFunctionArrayConversion(E: Result.get());
20767	}
20768
20769	namespace {
20770	/// A visitor for rebuilding an expression of type __unknown_anytype
20771	/// into one which resolves the type directly on the referring
20772	/// expression. Strict preservation of the original source
20773	/// structure is not a goal.
20774	struct RebuildUnknownAnyExpr
20775	: StmtVisitor<RebuildUnknownAnyExpr, ExprResult> {
20776
20777	Sema &S;
20778
20779	/// The current destination type.
20780	QualType DestType;
20781
20782	RebuildUnknownAnyExpr(Sema &S, QualType CastType)
20783	: S(S), DestType(CastType) {}
20784
20785	ExprResult VisitStmt(Stmt *S) {
20786	llvm_unreachable("unexpected statement!");
20787	}
20788
20789	ExprResult VisitExpr(Expr *E) {
20790	S.Diag(Loc: E->getExprLoc(), DiagID: diag::err_unsupported_unknown_any_expr)
20791	<< E->getSourceRange();
20792	return ExprError();
20793	}
20794
20795	ExprResult VisitCallExpr(CallExpr *E);
20796	ExprResult VisitObjCMessageExpr(ObjCMessageExpr *E);
20797
20798	/// Rebuild an expression which simply semantically wraps another
20799	/// expression which it shares the type and value kind of.
20800	template <class T> ExprResult rebuildSugarExpr(T *E) {
20801	ExprResult SubResult = Visit(S: E->getSubExpr());
20802	if (SubResult.isInvalid()) return ExprError();
20803	Expr *SubExpr = SubResult.get();
20804	E->setSubExpr(SubExpr);
20805	E->setType(SubExpr->getType());
20806	E->setValueKind(SubExpr->getValueKind());
20807	assert(E->getObjectKind() == OK_Ordinary);
20808	return E;
20809	}
20810
20811	ExprResult VisitParenExpr(ParenExpr *E) {
20812	return rebuildSugarExpr(E);
20813	}
20814
20815	ExprResult VisitUnaryExtension(UnaryOperator *E) {
20816	return rebuildSugarExpr(E);
20817	}
20818
20819	ExprResult VisitUnaryAddrOf(UnaryOperator *E) {
20820	const PointerType *Ptr = DestType->getAs<PointerType>();
20821	if (!Ptr) {
20822	S.Diag(Loc: E->getOperatorLoc(), DiagID: diag::err_unknown_any_addrof)
20823	<< E->getSourceRange();
20824	return ExprError();
20825	}
20826
20827	if (isa<CallExpr>(Val: E->getSubExpr())) {
20828	S.Diag(Loc: E->getOperatorLoc(), DiagID: diag::err_unknown_any_addrof_call)
20829	<< E->getSourceRange();
20830	return ExprError();
20831	}
20832
20833	assert(E->isPRValue());
20834	assert(E->getObjectKind() == OK_Ordinary);
20835	E->setType(DestType);
20836
20837	// Build the sub-expression as if it were an object of the pointee type.
20838	DestType = Ptr->getPointeeType();
20839	ExprResult SubResult = Visit(S: E->getSubExpr());
20840	if (SubResult.isInvalid()) return ExprError();
20841	E->setSubExpr(SubResult.get());
20842	return E;
20843	}
20844
20845	ExprResult VisitImplicitCastExpr(ImplicitCastExpr *E);
20846
20847	ExprResult resolveDecl(Expr *E, ValueDecl *VD);
20848
20849	ExprResult VisitMemberExpr(MemberExpr *E) {
20850	return resolveDecl(E, VD: E->getMemberDecl());
20851	}
20852
20853	ExprResult VisitDeclRefExpr(DeclRefExpr *E) {
20854	return resolveDecl(E, VD: E->getDecl());
20855	}
20856	};
20857	}
20858
20859	/// Rebuilds a call expression which yielded __unknown_anytype.
20860	ExprResult RebuildUnknownAnyExpr::VisitCallExpr(CallExpr *E) {
20861	Expr *CalleeExpr = E->getCallee();
20862
20863	enum FnKind {
20864	FK_MemberFunction,
20865	FK_FunctionPointer,
20866	FK_BlockPointer
20867	};
20868
20869	FnKind Kind;
20870	QualType CalleeType = CalleeExpr->getType();
20871	if (CalleeType == S.Context.BoundMemberTy) {
20872	assert(isa<CXXMemberCallExpr>(E) || isa<CXXOperatorCallExpr>(E));
20873	Kind = FK_MemberFunction;
20874	CalleeType = Expr::findBoundMemberType(expr: CalleeExpr);
20875	} else if (const PointerType *Ptr = CalleeType->getAs<PointerType>()) {
20876	CalleeType = Ptr->getPointeeType();
20877	Kind = FK_FunctionPointer;
20878	} else {
20879	CalleeType = CalleeType->castAs<BlockPointerType>()->getPointeeType();
20880	Kind = FK_BlockPointer;
20881	}
20882	const FunctionType *FnType = CalleeType->castAs<FunctionType>();
20883
20884	// Verify that this is a legal result type of a function.
20885	if ((DestType->isArrayType() && !S.getLangOpts().allowArrayReturnTypes()) ||
20886	DestType->isFunctionType()) {
20887	unsigned diagID = diag::err_func_returning_array_function;
20888	if (Kind == FK_BlockPointer)
20889	diagID = diag::err_block_returning_array_function;
20890
20891	S.Diag(Loc: E->getExprLoc(), DiagID: diagID)
20892	<< DestType->isFunctionType() << DestType;
20893	return ExprError();
20894	}
20895
20896	// Otherwise, go ahead and set DestType as the call's result.
20897	E->setType(DestType.getNonLValueExprType(Context: S.Context));
20898	E->setValueKind(Expr::getValueKindForType(T: DestType));
20899	assert(E->getObjectKind() == OK_Ordinary);
20900
20901	// Rebuild the function type, replacing the result type with DestType.
20902	const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(Val: FnType);
20903	if (Proto) {
20904	// __unknown_anytype(...) is a special case used by the debugger when
20905	// it has no idea what a function's signature is.
20906	//
20907	// We want to build this call essentially under the K&R
20908	// unprototyped rules, but making a FunctionNoProtoType in C++
20909	// would foul up all sorts of assumptions. However, we cannot
20910	// simply pass all arguments as variadic arguments, nor can we
20911	// portably just call the function under a non-variadic type; see
20912	// the comment on IR-gen's TargetInfo::isNoProtoCallVariadic.
20913	// However, it turns out that in practice it is generally safe to
20914	// call a function declared as "A foo(B,C,D);" under the prototype
20915	// "A foo(B,C,D,...);". The only known exception is with the
20916	// Windows ABI, where any variadic function is implicitly cdecl
20917	// regardless of its normal CC. Therefore we change the parameter
20918	// types to match the types of the arguments.
20919	//
20920	// This is a hack, but it is far superior to moving the
20921	// corresponding target-specific code from IR-gen to Sema/AST.
20922
20923	ArrayRef<QualType> ParamTypes = Proto->getParamTypes();
20924	SmallVector<QualType, 8> ArgTypes;
20925	if (ParamTypes.empty() && Proto->isVariadic()) { // the special case
20926	ArgTypes.reserve(N: E->getNumArgs());
20927	for (unsigned i = 0, e = E->getNumArgs(); i != e; ++i) {
20928	ArgTypes.push_back(Elt: S.Context.getReferenceQualifiedType(e: E->getArg(Arg: i)));
20929	}
20930	ParamTypes = ArgTypes;
20931	}
20932	DestType = S.Context.getFunctionType(ResultTy: DestType, Args: ParamTypes,
20933	EPI: Proto->getExtProtoInfo());
20934	} else {
20935	DestType = S.Context.getFunctionNoProtoType(ResultTy: DestType,
20936	Info: FnType->getExtInfo());
20937	}
20938
20939	// Rebuild the appropriate pointer-to-function type.
20940	switch (Kind) {
20941	case FK_MemberFunction:
20942	// Nothing to do.
20943	break;
20944
20945	case FK_FunctionPointer:
20946	DestType = S.Context.getPointerType(T: DestType);
20947	break;
20948
20949	case FK_BlockPointer:
20950	DestType = S.Context.getBlockPointerType(T: DestType);
20951	break;
20952	}
20953
20954	// Finally, we can recurse.
20955	ExprResult CalleeResult = Visit(S: CalleeExpr);
20956	if (!CalleeResult.isUsable()) return ExprError();
20957	E->setCallee(CalleeResult.get());
20958
20959	// Bind a temporary if necessary.
20960	return S.MaybeBindToTemporary(E);
20961	}
20962
20963	ExprResult RebuildUnknownAnyExpr::VisitObjCMessageExpr(ObjCMessageExpr *E) {
20964	// Verify that this is a legal result type of a call.
20965	if (DestType->isArrayType() || DestType->isFunctionType()) {
20966	S.Diag(Loc: E->getExprLoc(), DiagID: diag::err_func_returning_array_function)
20967	<< DestType->isFunctionType() << DestType;
20968	return ExprError();
20969	}
20970
20971	// Rewrite the method result type if available.
20972	if (ObjCMethodDecl *Method = E->getMethodDecl()) {
20973	assert(Method->getReturnType() == S.Context.UnknownAnyTy);
20974	Method->setReturnType(DestType);
20975	}
20976
20977	// Change the type of the message.
20978	E->setType(DestType.getNonReferenceType());
20979	E->setValueKind(Expr::getValueKindForType(T: DestType));
20980
20981	return S.MaybeBindToTemporary(E);
20982	}
20983
20984	ExprResult RebuildUnknownAnyExpr::VisitImplicitCastExpr(ImplicitCastExpr *E) {
20985	// The only case we should ever see here is a function-to-pointer decay.
20986	if (E->getCastKind() == CK_FunctionToPointerDecay) {
20987	assert(E->isPRValue());
20988	assert(E->getObjectKind() == OK_Ordinary);
20989
20990	E->setType(DestType);
20991
20992	// Rebuild the sub-expression as the pointee (function) type.
20993	DestType = DestType->castAs<PointerType>()->getPointeeType();
20994
20995	ExprResult Result = Visit(S: E->getSubExpr());
20996	if (!Result.isUsable()) return ExprError();
20997
20998	E->setSubExpr(Result.get());
20999	return E;
21000	} else if (E->getCastKind() == CK_LValueToRValue) {
21001	assert(E->isPRValue());
21002	assert(E->getObjectKind() == OK_Ordinary);
21003
21004	assert(isa<BlockPointerType>(E->getType()));
21005
21006	E->setType(DestType);
21007
21008	// The sub-expression has to be a lvalue reference, so rebuild it as such.
21009	DestType = S.Context.getLValueReferenceType(T: DestType);
21010
21011	ExprResult Result = Visit(S: E->getSubExpr());
21012	if (!Result.isUsable()) return ExprError();
21013
21014	E->setSubExpr(Result.get());
21015	return E;
21016	} else {
21017	llvm_unreachable("Unhandled cast type!");
21018	}
21019	}
21020
21021	ExprResult RebuildUnknownAnyExpr::resolveDecl(Expr *E, ValueDecl *VD) {
21022	ExprValueKind ValueKind = VK_LValue;
21023	QualType Type = DestType;
21024
21025	// We know how to make this work for certain kinds of decls:
21026
21027	// - functions
21028	if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Val: VD)) {
21029	if (const PointerType *Ptr = Type->getAs<PointerType>()) {
21030	DestType = Ptr->getPointeeType();
21031	ExprResult Result = resolveDecl(E, VD);
21032	if (Result.isInvalid()) return ExprError();
21033	return S.ImpCastExprToType(E: Result.get(), Type, CK: CK_FunctionToPointerDecay,
21034	VK: VK_PRValue);
21035	}
21036
21037	if (!Type->isFunctionType()) {
21038	S.Diag(Loc: E->getExprLoc(), DiagID: diag::err_unknown_any_function)
21039	<< VD << E->getSourceRange();
21040	return ExprError();
21041	}
21042	if (const FunctionProtoType *FT = Type->getAs<FunctionProtoType>()) {
21043	// We must match the FunctionDecl's type to the hack introduced in
21044	// RebuildUnknownAnyExpr::VisitCallExpr to vararg functions of unknown
21045	// type. See the lengthy commentary in that routine.
21046	QualType FDT = FD->getType();
21047	const FunctionType *FnType = FDT->castAs<FunctionType>();
21048	const FunctionProtoType *Proto = dyn_cast_or_null<FunctionProtoType>(Val: FnType);
21049	DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: E);
21050	if (DRE && Proto && Proto->getParamTypes().empty() && Proto->isVariadic()) {
21051	SourceLocation Loc = FD->getLocation();
21052	FunctionDecl *NewFD = FunctionDecl::Create(
21053	C&: S.Context, DC: FD->getDeclContext(), StartLoc: Loc, NLoc: Loc,
21054	N: FD->getNameInfo().getName(), T: DestType, TInfo: FD->getTypeSourceInfo(),
21055	SC: SC_None, UsesFPIntrin: S.getCurFPFeatures().isFPConstrained(),
21056	isInlineSpecified: false /*isInlineSpecified*/, hasWrittenPrototype: FD->hasPrototype(),
21057	/*ConstexprKind*/ ConstexprSpecKind::Unspecified);
21058
21059	if (FD->getQualifier())
21060	NewFD->setQualifierInfo(FD->getQualifierLoc());
21061
21062	SmallVector<ParmVarDecl*, 16> Params;
21063	for (const auto &AI : FT->param_types()) {
21064	ParmVarDecl *Param =
21065	S.BuildParmVarDeclForTypedef(DC: FD, Loc, T: AI);
21066	Param->setScopeInfo(scopeDepth: 0, parameterIndex: Params.size());
21067	Params.push_back(Elt: Param);
21068	}
21069	NewFD->setParams(Params);
21070	DRE->setDecl(NewFD);
21071	VD = DRE->getDecl();
21072	}
21073	}
21074
21075	if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Val: FD))
21076	if (MD->isInstance()) {
21077	ValueKind = VK_PRValue;
21078	Type = S.Context.BoundMemberTy;
21079	}
21080
21081	// Function references aren't l-values in C.
21082	if (!S.getLangOpts().CPlusPlus)
21083	ValueKind = VK_PRValue;
21084
21085	// - variables
21086	} else if (isa<VarDecl>(Val: VD)) {
21087	if (const ReferenceType *RefTy = Type->getAs<ReferenceType>()) {
21088	Type = RefTy->getPointeeType();
21089	} else if (Type->isFunctionType()) {
21090	S.Diag(Loc: E->getExprLoc(), DiagID: diag::err_unknown_any_var_function_type)
21091	<< VD << E->getSourceRange();
21092	return ExprError();
21093	}
21094
21095	// - nothing else
21096	} else {
21097	S.Diag(Loc: E->getExprLoc(), DiagID: diag::err_unsupported_unknown_any_decl)
21098	<< VD << E->getSourceRange();
21099	return ExprError();
21100	}
21101
21102	// Modifying the declaration like this is friendly to IR-gen but
21103	// also really dangerous.
21104	VD->setType(DestType);
21105	E->setType(Type);
21106	E->setValueKind(ValueKind);
21107	return E;
21108	}
21109
21110	ExprResult Sema::checkUnknownAnyCast(SourceRange TypeRange, QualType CastType,
21111	Expr *CastExpr, CastKind &CastKind,
21112	ExprValueKind &VK, CXXCastPath &Path) {
21113	// The type we're casting to must be either void or complete.
21114	if (!CastType->isVoidType() &&
21115	RequireCompleteType(Loc: TypeRange.getBegin(), T: CastType,
21116	DiagID: diag::err_typecheck_cast_to_incomplete))
21117	return ExprError();
21118
21119	// Rewrite the casted expression from scratch.
21120	ExprResult result = RebuildUnknownAnyExpr(*this, CastType).Visit(S: CastExpr);
21121	if (!result.isUsable()) return ExprError();
21122
21123	CastExpr = result.get();
21124	VK = CastExpr->getValueKind();
21125	CastKind = CK_NoOp;
21126
21127	return CastExpr;
21128	}
21129
21130	ExprResult Sema::forceUnknownAnyToType(Expr *E, QualType ToType) {
21131	return RebuildUnknownAnyExpr(*this, ToType).Visit(S: E);
21132	}
21133
21134	ExprResult Sema::checkUnknownAnyArg(SourceLocation callLoc,
21135	Expr *arg, QualType &paramType) {
21136	// If the syntactic form of the argument is not an explicit cast of
21137	// any sort, just do default argument promotion.
21138	ExplicitCastExpr *castArg = dyn_cast<ExplicitCastExpr>(Val: arg->IgnoreParens());
21139	if (!castArg) {
21140	ExprResult result = DefaultArgumentPromotion(E: arg);
21141	if (result.isInvalid()) return ExprError();
21142	paramType = result.get()->getType();
21143	return result;
21144	}
21145
21146	// Otherwise, use the type that was written in the explicit cast.
21147	assert(!arg->hasPlaceholderType());
21148	paramType = castArg->getTypeAsWritten();
21149
21150	// Copy-initialize a parameter of that type.
21151	InitializedEntity entity =
21152	InitializedEntity::InitializeParameter(Context, Type: paramType,
21153	/*consumed*/ Consumed: false);
21154	return PerformCopyInitialization(Entity: entity, EqualLoc: callLoc, Init: arg);
21155	}
21156
21157	static ExprResult diagnoseUnknownAnyExpr(Sema &S, Expr *E) {
21158	Expr *orig = E;
21159	unsigned diagID = diag::err_uncasted_use_of_unknown_any;
21160	while (true) {
21161	E = E->IgnoreParenImpCasts();
21162	if (CallExpr *call = dyn_cast<CallExpr>(Val: E)) {
21163	E = call->getCallee();
21164	diagID = diag::err_uncasted_call_of_unknown_any;
21165	} else {
21166	break;
21167	}
21168	}
21169
21170	SourceLocation loc;
21171	NamedDecl *d;
21172	if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(Val: E)) {
21173	loc = ref->getLocation();
21174	d = ref->getDecl();
21175	} else if (MemberExpr *mem = dyn_cast<MemberExpr>(Val: E)) {
21176	loc = mem->getMemberLoc();
21177	d = mem->getMemberDecl();
21178	} else if (ObjCMessageExpr *msg = dyn_cast<ObjCMessageExpr>(Val: E)) {
21179	diagID = diag::err_uncasted_call_of_unknown_any;
21180	loc = msg->getSelectorStartLoc();
21181	d = msg->getMethodDecl();
21182	if (!d) {
21183	S.Diag(Loc: loc, DiagID: diag::err_uncasted_send_to_unknown_any_method)
21184	<< static_cast<unsigned>(msg->isClassMessage()) << msg->getSelector()
21185	<< orig->getSourceRange();
21186	return ExprError();
21187	}
21188	} else {
21189	S.Diag(Loc: E->getExprLoc(), DiagID: diag::err_unsupported_unknown_any_expr)
21190	<< E->getSourceRange();
21191	return ExprError();
21192	}
21193
21194	S.Diag(Loc: loc, DiagID: diagID) << d << orig->getSourceRange();
21195
21196	// Never recoverable.
21197	return ExprError();
21198	}
21199
21200	ExprResult Sema::CheckPlaceholderExpr(Expr *E) {
21201	const BuiltinType *placeholderType = E->getType()->getAsPlaceholderType();
21202	if (!placeholderType) return E;
21203
21204	switch (placeholderType->getKind()) {
21205	case BuiltinType::UnresolvedTemplate: {
21206	auto *ULE = cast<UnresolvedLookupExpr>(Val: E);
21207	const DeclarationNameInfo &NameInfo = ULE->getNameInfo();
21208	// There's only one FoundDecl for UnresolvedTemplate type. See
21209	// BuildTemplateIdExpr.
21210	NamedDecl *Temp = *ULE->decls_begin();
21211	const bool IsTypeAliasTemplateDecl = isa<TypeAliasTemplateDecl>(Val: Temp);
21212
21213	NestedNameSpecifier *NNS = ULE->getQualifierLoc().getNestedNameSpecifier();
21214	// FIXME: AssumedTemplate is not very appropriate for error recovery here,
21215	// as it models only the unqualified-id case, where this case can clearly be
21216	// qualified. Thus we can't just qualify an assumed template.
21217	TemplateName TN;
21218	if (auto *TD = dyn_cast<TemplateDecl>(Val: Temp))
21219	TN = Context.getQualifiedTemplateName(NNS, TemplateKeyword: ULE->hasTemplateKeyword(),
21220	Template: TemplateName(TD));
21221	else
21222	TN = Context.getAssumedTemplateName(Name: NameInfo.getName());
21223
21224	Diag(Loc: NameInfo.getLoc(), DiagID: diag::err_template_kw_refers_to_type_template)
21225	<< TN << ULE->getSourceRange() << IsTypeAliasTemplateDecl;
21226	Diag(Loc: Temp->getLocation(), DiagID: diag::note_referenced_type_template)
21227	<< IsTypeAliasTemplateDecl;
21228
21229	TemplateArgumentListInfo TAL(ULE->getLAngleLoc(), ULE->getRAngleLoc());
21230	bool HasAnyDependentTA = false;
21231	for (const TemplateArgumentLoc &Arg : ULE->template_arguments()) {
21232	HasAnyDependentTA |= Arg.getArgument().isDependent();
21233	TAL.addArgument(Loc: Arg);
21234	}
21235
21236	QualType TST;
21237	{
21238	SFINAETrap Trap(*this);
21239	TST = CheckTemplateIdType(Template: TN, TemplateLoc: NameInfo.getBeginLoc(), TemplateArgs&: TAL);
21240	}
21241	if (TST.isNull())
21242	TST = Context.getTemplateSpecializationType(
21243	T: TN, SpecifiedArgs: ULE->template_arguments(), /*CanonicalArgs=*/{},
21244	Canon: HasAnyDependentTA ? Context.DependentTy : Context.IntTy);
21245	QualType ET =
21246	Context.getElaboratedType(Keyword: ElaboratedTypeKeyword::None, NNS, NamedType: TST);
21247	return CreateRecoveryExpr(Begin: NameInfo.getBeginLoc(), End: NameInfo.getEndLoc(), SubExprs: {},
21248	T: ET);
21249	}
21250
21251	// Overloaded expressions.
21252	case BuiltinType::Overload: {
21253	// Try to resolve a single function template specialization.
21254	// This is obligatory.
21255	ExprResult Result = E;
21256	if (ResolveAndFixSingleFunctionTemplateSpecialization(SrcExpr&: Result, DoFunctionPointerConversion: false))
21257	return Result;
21258
21259	// No guarantees that ResolveAndFixSingleFunctionTemplateSpecialization
21260	// leaves Result unchanged on failure.
21261	Result = E;
21262	if (resolveAndFixAddressOfSingleOverloadCandidate(SrcExpr&: Result))
21263	return Result;
21264
21265	// If that failed, try to recover with a call.
21266	tryToRecoverWithCall(E&: Result, PD: PDiag(DiagID: diag::err_ovl_unresolvable),
21267	/*complain*/ ForceComplain: true);
21268	return Result;
21269	}
21270
21271	// Bound member functions.
21272	case BuiltinType::BoundMember: {
21273	ExprResult result = E;
21274	const Expr *BME = E->IgnoreParens();
21275	PartialDiagnostic PD = PDiag(DiagID: diag::err_bound_member_function);
21276	// Try to give a nicer diagnostic if it is a bound member that we recognize.
21277	if (isa<CXXPseudoDestructorExpr>(Val: BME)) {
21278	PD = PDiag(DiagID: diag::err_dtor_expr_without_call) << /*pseudo-destructor*/ 1;
21279	} else if (const auto *ME = dyn_cast<MemberExpr>(Val: BME)) {
21280	if (ME->getMemberNameInfo().getName().getNameKind() ==
21281	DeclarationName::CXXDestructorName)
21282	PD = PDiag(DiagID: diag::err_dtor_expr_without_call) << /*destructor*/ 0;
21283	}
21284	tryToRecoverWithCall(E&: result, PD,
21285	/*complain*/ ForceComplain: true);
21286	return result;
21287	}
21288
21289	// ARC unbridged casts.
21290	case BuiltinType::ARCUnbridgedCast: {
21291	Expr *realCast = ObjC().stripARCUnbridgedCast(e: E);
21292	ObjC().diagnoseARCUnbridgedCast(e: realCast);
21293	return realCast;
21294	}
21295
21296	// Expressions of unknown type.
21297	case BuiltinType::UnknownAny:
21298	return diagnoseUnknownAnyExpr(S&: *this, E);
21299
21300	// Pseudo-objects.
21301	case BuiltinType::PseudoObject:
21302	return PseudoObject().checkRValue(E);
21303
21304	case BuiltinType::BuiltinFn: {
21305	// Accept __noop without parens by implicitly converting it to a call expr.
21306	auto *DRE = dyn_cast<DeclRefExpr>(Val: E->IgnoreParenImpCasts());
21307	if (DRE) {
21308	auto *FD = cast<FunctionDecl>(Val: DRE->getDecl());
21309	unsigned BuiltinID = FD->getBuiltinID();
21310	if (BuiltinID == Builtin::BI__noop) {
21311	E = ImpCastExprToType(E, Type: Context.getPointerType(T: FD->getType()),
21312	CK: CK_BuiltinFnToFnPtr)
21313	.get();
21314	return CallExpr::Create(Ctx: Context, Fn: E, /*Args=*/{}, Ty: Context.IntTy,
21315	VK: VK_PRValue, RParenLoc: SourceLocation(),
21316	FPFeatures: FPOptionsOverride());
21317	}
21318
21319	if (Context.BuiltinInfo.isInStdNamespace(ID: BuiltinID)) {
21320	// Any use of these other than a direct call is ill-formed as of C++20,
21321	// because they are not addressable functions. In earlier language
21322	// modes, warn and force an instantiation of the real body.
21323	Diag(Loc: E->getBeginLoc(),
21324	DiagID: getLangOpts().CPlusPlus20
21325	? diag::err_use_of_unaddressable_function
21326	: diag::warn_cxx20_compat_use_of_unaddressable_function);
21327	if (FD->isImplicitlyInstantiable()) {
21328	// Require a definition here because a normal attempt at
21329	// instantiation for a builtin will be ignored, and we won't try
21330	// again later. We assume that the definition of the template
21331	// precedes this use.
21332	InstantiateFunctionDefinition(PointOfInstantiation: E->getBeginLoc(), Function: FD,
21333	/*Recursive=*/false,
21334	/*DefinitionRequired=*/true,
21335	/*AtEndOfTU=*/false);
21336	}
21337	// Produce a properly-typed reference to the function.
21338	CXXScopeSpec SS;
21339	SS.Adopt(Other: DRE->getQualifierLoc());
21340	TemplateArgumentListInfo TemplateArgs;
21341	DRE->copyTemplateArgumentsInto(List&: TemplateArgs);
21342	return BuildDeclRefExpr(
21343	D: FD, Ty: FD->getType(), VK: VK_LValue, NameInfo: DRE->getNameInfo(),
21344	SS: DRE->hasQualifier() ? &SS : nullptr, FoundD: DRE->getFoundDecl(),
21345	TemplateKWLoc: DRE->getTemplateKeywordLoc(),
21346	TemplateArgs: DRE->hasExplicitTemplateArgs() ? &TemplateArgs : nullptr);
21347	}
21348	}
21349
21350	Diag(Loc: E->getBeginLoc(), DiagID: diag::err_builtin_fn_use);
21351	return ExprError();
21352	}
21353
21354	case BuiltinType::IncompleteMatrixIdx:
21355	Diag(Loc: cast<MatrixSubscriptExpr>(Val: E->IgnoreParens())
21356	->getRowIdx()
21357	->getBeginLoc(),
21358	DiagID: diag::err_matrix_incomplete_index);
21359	return ExprError();
21360
21361	// Expressions of unknown type.
21362	case BuiltinType::ArraySection:
21363	Diag(Loc: E->getBeginLoc(), DiagID: diag::err_array_section_use)
21364	<< cast<ArraySectionExpr>(Val: E)->isOMPArraySection();
21365	return ExprError();
21366
21367	// Expressions of unknown type.
21368	case BuiltinType::OMPArrayShaping:
21369	return ExprError(Diag(Loc: E->getBeginLoc(), DiagID: diag::err_omp_array_shaping_use));
21370
21371	case BuiltinType::OMPIterator:
21372	return ExprError(Diag(Loc: E->getBeginLoc(), DiagID: diag::err_omp_iterator_use));
21373
21374	// Everything else should be impossible.
21375	#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
21376	case BuiltinType::Id:
21377	#include "clang/Basic/OpenCLImageTypes.def"
21378	#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
21379	case BuiltinType::Id:
21380	#include "clang/Basic/OpenCLExtensionTypes.def"
21381	#define SVE_TYPE(Name, Id, SingletonId) \
21382	case BuiltinType::Id:
21383	#include "clang/Basic/AArch64ACLETypes.def"
21384	#define PPC_VECTOR_TYPE(Name, Id, Size) \
21385	case BuiltinType::Id:
21386	#include "clang/Basic/PPCTypes.def"
21387	#define RVV_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
21388	#include "clang/Basic/RISCVVTypes.def"
21389	#define WASM_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
21390	#include "clang/Basic/WebAssemblyReferenceTypes.def"
21391	#define AMDGPU_TYPE(Name, Id, SingletonId, Width, Align) case BuiltinType::Id:
21392	#include "clang/Basic/AMDGPUTypes.def"
21393	#define HLSL_INTANGIBLE_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
21394	#include "clang/Basic/HLSLIntangibleTypes.def"
21395	#define BUILTIN_TYPE(Id, SingletonId) case BuiltinType::Id:
21396	#define PLACEHOLDER_TYPE(Id, SingletonId)
21397	#include "clang/AST/BuiltinTypes.def"
21398	break;
21399	}
21400
21401	llvm_unreachable("invalid placeholder type!");
21402	}
21403
21404	bool Sema::CheckCaseExpression(Expr *E) {
21405	if (E->isTypeDependent())
21406	return true;
21407	if (E->isValueDependent() || E->isIntegerConstantExpr(Ctx: Context))
21408	return E->getType()->isIntegralOrEnumerationType();
21409	return false;
21410	}
21411
21412	ExprResult Sema::CreateRecoveryExpr(SourceLocation Begin, SourceLocation End,
21413	ArrayRef<Expr *> SubExprs, QualType T) {
21414	if (!Context.getLangOpts().RecoveryAST)
21415	return ExprError();
21416
21417	if (isSFINAEContext())
21418	return ExprError();
21419
21420	if (T.isNull() || T->isUndeducedType() ||
21421	!Context.getLangOpts().RecoveryASTType)
21422	// We don't know the concrete type, fallback to dependent type.
21423	T = Context.DependentTy;
21424
21425	return RecoveryExpr::Create(Ctx&: Context, T, BeginLoc: Begin, EndLoc: End, SubExprs);
21426	}
21427