1	//===--- SemaExprObjC.cpp - Semantic Analysis for ObjC 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 Objective-C expressions.
10	//
11	//===----------------------------------------------------------------------===//
12
13	#include "clang/AST/ASTContext.h"
14	#include "clang/AST/DeclObjC.h"
15	#include "clang/AST/ExprObjC.h"
16	#include "clang/AST/StmtVisitor.h"
17	#include "clang/AST/TypeLoc.h"
18	#include "clang/Analysis/DomainSpecific/CocoaConventions.h"
19	#include "clang/Basic/Builtins.h"
20	#include "clang/Edit/Commit.h"
21	#include "clang/Edit/Rewriters.h"
22	#include "clang/Lex/Preprocessor.h"
23	#include "clang/Sema/Initialization.h"
24	#include "clang/Sema/Lookup.h"
25	#include "clang/Sema/Scope.h"
26	#include "clang/Sema/ScopeInfo.h"
27	#include "clang/Sema/SemaInternal.h"
28	#include "llvm/ADT/SmallString.h"
29	#include "llvm/Support/ConvertUTF.h"
30	#include <optional>
31
32	using namespace clang;
33	using namespace sema;
34	using llvm::ArrayRef;
35
36	ExprResult Sema::ParseObjCStringLiteral(SourceLocation *AtLocs,
37	ArrayRef<Expr *> Strings) {
38	// Most ObjC strings are formed out of a single piece. However, we *can*
39	// have strings formed out of multiple @ strings with multiple pptokens in
40	// each one, e.g. @"foo" "bar" @"baz" "qux" which need to be turned into one
41	// StringLiteral for ObjCStringLiteral to hold onto.
42	StringLiteral *S = cast<StringLiteral>(Val: Strings[0]);
43
44	// If we have a multi-part string, merge it all together.
45	if (Strings.size() != 1) {
46	// Concatenate objc strings.
47	SmallString<128> StrBuf;
48	SmallVector<SourceLocation, 8> StrLocs;
49
50	for (Expr *E : Strings) {
51	S = cast<StringLiteral>(Val: E);
52
53	// ObjC strings can't be wide or UTF.
54	if (!S->isOrdinary()) {
55	Diag(S->getBeginLoc(), diag::err_cfstring_literal_not_string_constant)
56	<< S->getSourceRange();
57	return true;
58	}
59
60	// Append the string.
61	StrBuf += S->getString();
62
63	// Get the locations of the string tokens.
64	StrLocs.append(in_start: S->tokloc_begin(), in_end: S->tokloc_end());
65	}
66
67	// Create the aggregate string with the appropriate content and location
68	// information.
69	const ConstantArrayType *CAT = Context.getAsConstantArrayType(T: S->getType());
70	assert(CAT && "String literal not of constant array type!");
71	QualType StrTy = Context.getConstantArrayType(
72	EltTy: CAT->getElementType(), ArySize: llvm::APInt(32, StrBuf.size() + 1), SizeExpr: nullptr,
73	ASM: CAT->getSizeModifier(), IndexTypeQuals: CAT->getIndexTypeCVRQualifiers());
74	S = StringLiteral::Create(Ctx: Context, Str: StrBuf, Kind: StringLiteralKind::Ordinary,
75	/*Pascal=*/false, Ty: StrTy, Loc: &StrLocs[0],
76	NumConcatenated: StrLocs.size());
77	}
78
79	return BuildObjCStringLiteral(AtLoc: AtLocs[0], S);
80	}
81
82	ExprResult Sema::BuildObjCStringLiteral(SourceLocation AtLoc, StringLiteral *S){
83	// Verify that this composite string is acceptable for ObjC strings.
84	if (CheckObjCString(S))
85	return true;
86
87	// Initialize the constant string interface lazily. This assumes
88	// the NSString interface is seen in this translation unit. Note: We
89	// don't use NSConstantString, since the runtime team considers this
90	// interface private (even though it appears in the header files).
91	QualType Ty = Context.getObjCConstantStringInterface();
92	if (!Ty.isNull()) {
93	Ty = Context.getObjCObjectPointerType(OIT: Ty);
94	} else if (getLangOpts().NoConstantCFStrings) {
95	IdentifierInfo *NSIdent=nullptr;
96	std::string StringClass(getLangOpts().ObjCConstantStringClass);
97
98	if (StringClass.empty())
99	NSIdent = &Context.Idents.get(Name: "NSConstantString");
100	else
101	NSIdent = &Context.Idents.get(Name: StringClass);
102
103	NamedDecl *IF = LookupSingleName(S: TUScope, Name: NSIdent, Loc: AtLoc,
104	NameKind: LookupOrdinaryName);
105	if (ObjCInterfaceDecl *StrIF = dyn_cast_or_null<ObjCInterfaceDecl>(Val: IF)) {
106	Context.setObjCConstantStringInterface(StrIF);
107	Ty = Context.getObjCConstantStringInterface();
108	Ty = Context.getObjCObjectPointerType(OIT: Ty);
109	} else {
110	// If there is no NSConstantString interface defined then treat this
111	// as error and recover from it.
112	Diag(S->getBeginLoc(), diag::err_no_nsconstant_string_class)
113	<< NSIdent << S->getSourceRange();
114	Ty = Context.getObjCIdType();
115	}
116	} else {
117	IdentifierInfo *NSIdent = NSAPIObj->getNSClassId(K: NSAPI::ClassId_NSString);
118	NamedDecl *IF = LookupSingleName(S: TUScope, Name: NSIdent, Loc: AtLoc,
119	NameKind: LookupOrdinaryName);
120	if (ObjCInterfaceDecl *StrIF = dyn_cast_or_null<ObjCInterfaceDecl>(Val: IF)) {
121	Context.setObjCConstantStringInterface(StrIF);
122	Ty = Context.getObjCConstantStringInterface();
123	Ty = Context.getObjCObjectPointerType(OIT: Ty);
124	} else {
125	// If there is no NSString interface defined, implicitly declare
126	// a @class NSString; and use that instead. This is to make sure
127	// type of an NSString literal is represented correctly, instead of
128	// being an 'id' type.
129	Ty = Context.getObjCNSStringType();
130	if (Ty.isNull()) {
131	ObjCInterfaceDecl *NSStringIDecl =
132	ObjCInterfaceDecl::Create (Context,
133	Context.getTranslationUnitDecl(),
134	SourceLocation(), NSIdent,
135	nullptr, nullptr, SourceLocation());
136	Ty = Context.getObjCInterfaceType(Decl: NSStringIDecl);
137	Context.setObjCNSStringType(Ty);
138	}
139	Ty = Context.getObjCObjectPointerType(OIT: Ty);
140	}
141	}
142
143	return new (Context) ObjCStringLiteral(S, Ty, AtLoc);
144	}
145
146	/// Emits an error if the given method does not exist, or if the return
147	/// type is not an Objective-C object.
148	static bool validateBoxingMethod(Sema &S, SourceLocation Loc,
149	const ObjCInterfaceDecl *Class,
150	Selector Sel, const ObjCMethodDecl *Method) {
151	if (!Method) {
152	// FIXME: Is there a better way to avoid quotes than using getName()?
153	S.Diag(Loc, diag::err_undeclared_boxing_method) << Sel << Class->getName();
154	return false;
155	}
156
157	// Make sure the return type is reasonable.
158	QualType ReturnType = Method->getReturnType();
159	if (!ReturnType->isObjCObjectPointerType()) {
160	S.Diag(Loc, diag::err_objc_literal_method_sig)
161	<< Sel;
162	S.Diag(Method->getLocation(), diag::note_objc_literal_method_return)
163	<< ReturnType;
164	return false;
165	}
166
167	return true;
168	}
169
170	/// Maps ObjCLiteralKind to NSClassIdKindKind
171	static NSAPI::NSClassIdKindKind ClassKindFromLiteralKind(
172	Sema::ObjCLiteralKind LiteralKind) {
173	switch (LiteralKind) {
174	case Sema::LK_Array:
175	return NSAPI::ClassId_NSArray;
176	case Sema::LK_Dictionary:
177	return NSAPI::ClassId_NSDictionary;
178	case Sema::LK_Numeric:
179	return NSAPI::ClassId_NSNumber;
180	case Sema::LK_String:
181	return NSAPI::ClassId_NSString;
182	case Sema::LK_Boxed:
183	return NSAPI::ClassId_NSValue;
184
185	// there is no corresponding matching
186	// between LK_None/LK_Block and NSClassIdKindKind
187	case Sema::LK_Block:
188	case Sema::LK_None:
189	break;
190	}
191	llvm_unreachable("LiteralKind can't be converted into a ClassKind");
192	}
193
194	/// Validates ObjCInterfaceDecl availability.
195	/// ObjCInterfaceDecl, used to create ObjC literals, should be defined
196	/// if clang not in a debugger mode.
197	static bool ValidateObjCLiteralInterfaceDecl(Sema &S, ObjCInterfaceDecl *Decl,
198	SourceLocation Loc,
199	Sema::ObjCLiteralKind LiteralKind) {
200	if (!Decl) {
201	NSAPI::NSClassIdKindKind Kind = ClassKindFromLiteralKind(LiteralKind);
202	IdentifierInfo *II = S.NSAPIObj->getNSClassId(K: Kind);
203	S.Diag(Loc, diag::err_undeclared_objc_literal_class)
204	<< II->getName() << LiteralKind;
205	return false;
206	} else if (!Decl->hasDefinition() && !S.getLangOpts().DebuggerObjCLiteral) {
207	S.Diag(Loc, diag::err_undeclared_objc_literal_class)
208	<< Decl->getName() << LiteralKind;
209	S.Diag(Decl->getLocation(), diag::note_forward_class);
210	return false;
211	}
212
213	return true;
214	}
215
216	/// Looks up ObjCInterfaceDecl of a given NSClassIdKindKind.
217	/// Used to create ObjC literals, such as NSDictionary (@{}),
218	/// NSArray (@[]) and Boxed Expressions (@())
219	static ObjCInterfaceDecl *LookupObjCInterfaceDeclForLiteral(Sema &S,
220	SourceLocation Loc,
221	Sema::ObjCLiteralKind LiteralKind) {
222	NSAPI::NSClassIdKindKind ClassKind = ClassKindFromLiteralKind(LiteralKind);
223	IdentifierInfo *II = S.NSAPIObj->getNSClassId(K: ClassKind);
224	NamedDecl *IF = S.LookupSingleName(S: S.TUScope, Name: II, Loc,
225	NameKind: Sema::LookupOrdinaryName);
226	ObjCInterfaceDecl *ID = dyn_cast_or_null<ObjCInterfaceDecl>(Val: IF);
227	if (!ID && S.getLangOpts().DebuggerObjCLiteral) {
228	ASTContext &Context = S.Context;
229	TranslationUnitDecl *TU = Context.getTranslationUnitDecl();
230	ID = ObjCInterfaceDecl::Create (Context, TU, SourceLocation(), II,
231	nullptr, nullptr, SourceLocation());
232	}
233
234	if (!ValidateObjCLiteralInterfaceDecl(S, Decl: ID, Loc, LiteralKind)) {
235	ID = nullptr;
236	}
237
238	return ID;
239	}
240
241	/// Retrieve the NSNumber factory method that should be used to create
242	/// an Objective-C literal for the given type.
243	static ObjCMethodDecl *getNSNumberFactoryMethod(Sema &S, SourceLocation Loc,
244	QualType NumberType,
245	bool isLiteral = false,
246	SourceRange R = SourceRange()) {
247	std::optional<NSAPI::NSNumberLiteralMethodKind> Kind =
248	S.NSAPIObj->getNSNumberFactoryMethodKind(T: NumberType);
249
250	if (!Kind) {
251	if (isLiteral) {
252	S.Diag(Loc, diag::err_invalid_nsnumber_type)
253	<< NumberType << R;
254	}
255	return nullptr;
256	}
257
258	// If we already looked up this method, we're done.
259	if (S.NSNumberLiteralMethods[*Kind])
260	return S.NSNumberLiteralMethods[*Kind];
261
262	Selector Sel = S.NSAPIObj->getNSNumberLiteralSelector(MK: *Kind,
263	/*Instance=*/false);
264
265	ASTContext &CX = S.Context;
266
267	// Look up the NSNumber class, if we haven't done so already. It's cached
268	// in the Sema instance.
269	if (!S.NSNumberDecl) {
270	S.NSNumberDecl = LookupObjCInterfaceDeclForLiteral(S, Loc,
271	LiteralKind: Sema::LK_Numeric);
272	if (!S.NSNumberDecl) {
273	return nullptr;
274	}
275	}
276
277	if (S.NSNumberPointer.isNull()) {
278	// generate the pointer to NSNumber type.
279	QualType NSNumberObject = CX.getObjCInterfaceType(Decl: S.NSNumberDecl);
280	S.NSNumberPointer = CX.getObjCObjectPointerType(OIT: NSNumberObject);
281	}
282
283	// Look for the appropriate method within NSNumber.
284	ObjCMethodDecl *Method = S.NSNumberDecl->lookupClassMethod(Sel);
285	if (!Method && S.getLangOpts().DebuggerObjCLiteral) {
286	// create a stub definition this NSNumber factory method.
287	TypeSourceInfo *ReturnTInfo = nullptr;
288	Method = ObjCMethodDecl::Create(
289	C&: CX, beginLoc: SourceLocation(), endLoc: SourceLocation(), SelInfo: Sel, T: S.NSNumberPointer,
290	ReturnTInfo, contextDecl: S.NSNumberDecl,
291	/*isInstance=*/false, /*isVariadic=*/false,
292	/*isPropertyAccessor=*/false,
293	/*isSynthesizedAccessorStub=*/false,
294	/*isImplicitlyDeclared=*/true,
295	/*isDefined=*/false, impControl: ObjCImplementationControl::Required,
296	/*HasRelatedResultType=*/false);
297	ParmVarDecl *value = ParmVarDecl::Create(S.Context, Method,
298	SourceLocation(), SourceLocation(),
299	&CX.Idents.get(Name: "value"),
300	NumberType, /*TInfo=*/nullptr,
301	SC_None, nullptr);
302	Method->setMethodParams(C&: S.Context, Params: value, SelLocs: std::nullopt);
303	}
304
305	if (!validateBoxingMethod(S, Loc, Class: S.NSNumberDecl, Sel, Method))
306	return nullptr;
307
308	// Note: if the parameter type is out-of-line, we'll catch it later in the
309	// implicit conversion.
310
311	S.NSNumberLiteralMethods[*Kind] = Method;
312	return Method;
313	}
314
315	/// BuildObjCNumericLiteral - builds an ObjCBoxedExpr AST node for the
316	/// numeric literal expression. Type of the expression will be "NSNumber *".
317	ExprResult Sema::BuildObjCNumericLiteral(SourceLocation AtLoc, Expr *Number) {
318	// Determine the type of the literal.
319	QualType NumberType = Number->getType();
320	if (CharacterLiteral *Char = dyn_cast<CharacterLiteral>(Val: Number)) {
321	// In C, character literals have type 'int'. That's not the type we want
322	// to use to determine the Objective-c literal kind.
323	switch (Char->getKind()) {
324	case CharacterLiteralKind::Ascii:
325	case CharacterLiteralKind::UTF8:
326	NumberType = Context.CharTy;
327	break;
328
329	case CharacterLiteralKind::Wide:
330	NumberType = Context.getWideCharType();
331	break;
332
333	case CharacterLiteralKind::UTF16:
334	NumberType = Context.Char16Ty;
335	break;
336
337	case CharacterLiteralKind::UTF32:
338	NumberType = Context.Char32Ty;
339	break;
340	}
341	}
342
343	// Look for the appropriate method within NSNumber.
344	// Construct the literal.
345	SourceRange NR(Number->getSourceRange());
346	ObjCMethodDecl *Method = getNSNumberFactoryMethod(S&: *this, Loc: AtLoc, NumberType,
347	isLiteral: true, R: NR);
348	if (!Method)
349	return ExprError();
350
351	// Convert the number to the type that the parameter expects.
352	ParmVarDecl *ParamDecl = Method->parameters()[0];
353	InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
354	Parm: ParamDecl);
355	ExprResult ConvertedNumber = PerformCopyInitialization(Entity,
356	EqualLoc: SourceLocation(),
357	Init: Number);
358	if (ConvertedNumber.isInvalid())
359	return ExprError();
360	Number = ConvertedNumber.get();
361
362	// Use the effective source range of the literal, including the leading '@'.
363	return MaybeBindToTemporary(
364	new (Context) ObjCBoxedExpr(Number, NSNumberPointer, Method,
365	SourceRange(AtLoc, NR.getEnd())));
366	}
367
368	ExprResult Sema::ActOnObjCBoolLiteral(SourceLocation AtLoc,
369	SourceLocation ValueLoc,
370	bool Value) {
371	ExprResult Inner;
372	if (getLangOpts().CPlusPlus) {
373	Inner = ActOnCXXBoolLiteral(OpLoc: ValueLoc, Kind: Value? tok::kw_true : tok::kw_false);
374	} else {
375	// C doesn't actually have a way to represent literal values of type
376	// _Bool. So, we'll use 0/1 and implicit cast to _Bool.
377	Inner = ActOnIntegerConstant(Loc: ValueLoc, Val: Value? 1 : 0);
378	Inner = ImpCastExprToType(E: Inner.get(), Type: Context.BoolTy,
379	CK: CK_IntegralToBoolean);
380	}
381
382	return BuildObjCNumericLiteral(AtLoc, Number: Inner.get());
383	}
384
385	/// Check that the given expression is a valid element of an Objective-C
386	/// collection literal.
387	static ExprResult CheckObjCCollectionLiteralElement(Sema &S, Expr *Element,
388	QualType T,
389	bool ArrayLiteral = false) {
390	// If the expression is type-dependent, there's nothing for us to do.
391	if (Element->isTypeDependent())
392	return Element;
393
394	ExprResult Result = S.CheckPlaceholderExpr(E: Element);
395	if (Result.isInvalid())
396	return ExprError();
397	Element = Result.get();
398
399	// In C++, check for an implicit conversion to an Objective-C object pointer
400	// type.
401	if (S.getLangOpts().CPlusPlus && Element->getType()->isRecordType()) {
402	InitializedEntity Entity
403	= InitializedEntity::InitializeParameter(Context&: S.Context, Type: T,
404	/*Consumed=*/false);
405	InitializationKind Kind = InitializationKind::CreateCopy(
406	InitLoc: Element->getBeginLoc(), EqualLoc: SourceLocation());
407	InitializationSequence Seq(S, Entity, Kind, Element);
408	if (!Seq.Failed())
409	return Seq.Perform(S, Entity, Kind, Args: Element);
410	}
411
412	Expr *OrigElement = Element;
413
414	// Perform lvalue-to-rvalue conversion.
415	Result = S.DefaultLvalueConversion(E: Element);
416	if (Result.isInvalid())
417	return ExprError();
418	Element = Result.get();
419
420	// Make sure that we have an Objective-C pointer type or block.
421	if (!Element->getType()->isObjCObjectPointerType() &&
422	!Element->getType()->isBlockPointerType()) {
423	bool Recovered = false;
424
425	// If this is potentially an Objective-C numeric literal, add the '@'.
426	if (isa<IntegerLiteral>(Val: OrigElement) ||
427	isa<CharacterLiteral>(Val: OrigElement) ||
428	isa<FloatingLiteral>(Val: OrigElement) ||
429	isa<ObjCBoolLiteralExpr>(Val: OrigElement) ||
430	isa<CXXBoolLiteralExpr>(Val: OrigElement)) {
431	if (S.NSAPIObj->getNSNumberFactoryMethodKind(T: OrigElement->getType())) {
432	int Which = isa<CharacterLiteral>(Val: OrigElement) ? 1
433	: (isa<CXXBoolLiteralExpr>(Val: OrigElement) ||
434	isa<ObjCBoolLiteralExpr>(Val: OrigElement)) ? 2
435	: 3;
436
437	S.Diag(OrigElement->getBeginLoc(), diag::err_box_literal_collection)
438	<< Which << OrigElement->getSourceRange()
439	<< FixItHint::CreateInsertion(OrigElement->getBeginLoc(), "@");
440
441	Result =
442	S.BuildObjCNumericLiteral(AtLoc: OrigElement->getBeginLoc(), Number: OrigElement);
443	if (Result.isInvalid())
444	return ExprError();
445
446	Element = Result.get();
447	Recovered = true;
448	}
449	}
450	// If this is potentially an Objective-C string literal, add the '@'.
451	else if (StringLiteral *String = dyn_cast<StringLiteral>(Val: OrigElement)) {
452	if (String->isOrdinary()) {
453	S.Diag(OrigElement->getBeginLoc(), diag::err_box_literal_collection)
454	<< 0 << OrigElement->getSourceRange()
455	<< FixItHint::CreateInsertion(OrigElement->getBeginLoc(), "@");
456
457	Result = S.BuildObjCStringLiteral(AtLoc: OrigElement->getBeginLoc(), S: String);
458	if (Result.isInvalid())
459	return ExprError();
460
461	Element = Result.get();
462	Recovered = true;
463	}
464	}
465
466	if (!Recovered) {
467	S.Diag(Element->getBeginLoc(), diag::err_invalid_collection_element)
468	<< Element->getType();
469	return ExprError();
470	}
471	}
472	if (ArrayLiteral)
473	if (ObjCStringLiteral *getString =
474	dyn_cast<ObjCStringLiteral>(Val: OrigElement)) {
475	if (StringLiteral *SL = getString->getString()) {
476	unsigned numConcat = SL->getNumConcatenated();
477	if (numConcat > 1) {
478	// Only warn if the concatenated string doesn't come from a macro.
479	bool hasMacro = false;
480	for (unsigned i = 0; i < numConcat ; ++i)
481	if (SL->getStrTokenLoc(TokNum: i).isMacroID()) {
482	hasMacro = true;
483	break;
484	}
485	if (!hasMacro)
486	S.Diag(Element->getBeginLoc(),
487	diag::warn_concatenated_nsarray_literal)
488	<< Element->getType();
489	}
490	}
491	}
492
493	// Make sure that the element has the type that the container factory
494	// function expects.
495	return S.PerformCopyInitialization(
496	Entity: InitializedEntity::InitializeParameter(Context&: S.Context, Type: T,
497	/*Consumed=*/false),
498	EqualLoc: Element->getBeginLoc(), Init: Element);
499	}
500
501	ExprResult Sema::BuildObjCBoxedExpr(SourceRange SR, Expr *ValueExpr) {
502	if (ValueExpr->isTypeDependent()) {
503	ObjCBoxedExpr *BoxedExpr =
504	new (Context) ObjCBoxedExpr(ValueExpr, Context.DependentTy, nullptr, SR);
505	return BoxedExpr;
506	}
507	ObjCMethodDecl *BoxingMethod = nullptr;
508	QualType BoxedType;
509	// Convert the expression to an RValue, so we can check for pointer types...
510	ExprResult RValue = DefaultFunctionArrayLvalueConversion(E: ValueExpr);
511	if (RValue.isInvalid()) {
512	return ExprError();
513	}
514	SourceLocation Loc = SR.getBegin();
515	ValueExpr = RValue.get();
516	QualType ValueType(ValueExpr->getType());
517	if (const PointerType *PT = ValueType->getAs<PointerType>()) {
518	QualType PointeeType = PT->getPointeeType();
519	if (Context.hasSameUnqualifiedType(T1: PointeeType, T2: Context.CharTy)) {
520
521	if (!NSStringDecl) {
522	NSStringDecl = LookupObjCInterfaceDeclForLiteral(S&: *this, Loc,
523	LiteralKind: Sema::LK_String);
524	if (!NSStringDecl) {
525	return ExprError();
526	}
527	QualType NSStringObject = Context.getObjCInterfaceType(Decl: NSStringDecl);
528	NSStringPointer = Context.getObjCObjectPointerType(NSStringObject);
529	}
530
531	// The boxed expression can be emitted as a compile time constant if it is
532	// a string literal whose character encoding is compatible with UTF-8.
533	if (auto *CE = dyn_cast<ImplicitCastExpr>(Val: ValueExpr))
534	if (CE->getCastKind() == CK_ArrayToPointerDecay)
535	if (auto *SL =
536	dyn_cast<StringLiteral>(CE->getSubExpr()->IgnoreParens())) {
537	assert((SL->isOrdinary() || SL->isUTF8()) &&
538	"unexpected character encoding");
539	StringRef Str = SL->getString();
540	const llvm::UTF8 *StrBegin = Str.bytes_begin();
541	const llvm::UTF8 *StrEnd = Str.bytes_end();
542	// Check that this is a valid UTF-8 string.
543	if (llvm::isLegalUTF8String(source: &StrBegin, sourceEnd: StrEnd)) {
544	BoxedType = Context.getAttributedType(
545	AttributedType::getNullabilityAttrKind(
546	NullabilityKind::NonNull),
547	NSStringPointer, NSStringPointer);
548	return new (Context) ObjCBoxedExpr(CE, BoxedType, nullptr, SR);
549	}
550
551	Diag(SL->getBeginLoc(), diag::warn_objc_boxing_invalid_utf8_string)
552	<< NSStringPointer << SL->getSourceRange();
553	}
554
555	if (!StringWithUTF8StringMethod) {
556	IdentifierInfo *II = &Context.Idents.get(Name: "stringWithUTF8String");
557	Selector stringWithUTF8String = Context.Selectors.getUnarySelector(ID: II);
558
559	// Look for the appropriate method within NSString.
560	BoxingMethod = NSStringDecl->lookupClassMethod(Sel: stringWithUTF8String);
561	if (!BoxingMethod && getLangOpts().DebuggerObjCLiteral) {
562	// Debugger needs to work even if NSString hasn't been defined.
563	TypeSourceInfo *ReturnTInfo = nullptr;
564	ObjCMethodDecl *M = ObjCMethodDecl::Create(
565	Context, SourceLocation(), SourceLocation(), stringWithUTF8String,
566	NSStringPointer, ReturnTInfo, NSStringDecl,
567	/*isInstance=*/false, /*isVariadic=*/false,
568	/*isPropertyAccessor=*/false,
569	/*isSynthesizedAccessorStub=*/false,
570	/*isImplicitlyDeclared=*/true,
571	/*isDefined=*/false, ObjCImplementationControl::Required,
572	/*HasRelatedResultType=*/false);
573	QualType ConstCharType = Context.CharTy.withConst();
574	ParmVarDecl *value =
575	ParmVarDecl::Create(Context, M,
576	SourceLocation(), SourceLocation(),
577	&Context.Idents.get(Name: "value"),
578	Context.getPointerType(T: ConstCharType),
579	/*TInfo=*/nullptr,
580	SC_None, nullptr);
581	M->setMethodParams(C&: Context, Params: value, SelLocs: std::nullopt);
582	BoxingMethod = M;
583	}
584
585	if (!validateBoxingMethod(S&: *this, Loc, Class: NSStringDecl,
586	Sel: stringWithUTF8String, Method: BoxingMethod))
587	return ExprError();
588
589	StringWithUTF8StringMethod = BoxingMethod;
590	}
591
592	BoxingMethod = StringWithUTF8StringMethod;
593	BoxedType = NSStringPointer;
594	// Transfer the nullability from method's return type.
595	std::optional<NullabilityKind> Nullability =
596	BoxingMethod->getReturnType()->getNullability();
597	if (Nullability)
598	BoxedType = Context.getAttributedType(
599	attrKind: AttributedType::getNullabilityAttrKind(kind: *Nullability), modifiedType: BoxedType,
600	equivalentType: BoxedType);
601	}
602	} else if (ValueType->isBuiltinType()) {
603	// The other types we support are numeric, char and BOOL/bool. We could also
604	// provide limited support for structure types, such as NSRange, NSRect, and
605	// NSSize. See NSValue (NSValueGeometryExtensions) in <Foundation/NSGeometry.h>
606	// for more details.
607
608	// Check for a top-level character literal.
609	if (const CharacterLiteral *Char =
610	dyn_cast<CharacterLiteral>(Val: ValueExpr->IgnoreParens())) {
611	// In C, character literals have type 'int'. That's not the type we want
612	// to use to determine the Objective-c literal kind.
613	switch (Char->getKind()) {
614	case CharacterLiteralKind::Ascii:
615	case CharacterLiteralKind::UTF8:
616	ValueType = Context.CharTy;
617	break;
618
619	case CharacterLiteralKind::Wide:
620	ValueType = Context.getWideCharType();
621	break;
622
623	case CharacterLiteralKind::UTF16:
624	ValueType = Context.Char16Ty;
625	break;
626
627	case CharacterLiteralKind::UTF32:
628	ValueType = Context.Char32Ty;
629	break;
630	}
631	}
632	// FIXME: Do I need to do anything special with BoolTy expressions?
633
634	// Look for the appropriate method within NSNumber.
635	BoxingMethod = getNSNumberFactoryMethod(S&: *this, Loc, NumberType: ValueType);
636	BoxedType = NSNumberPointer;
637	} else if (const EnumType *ET = ValueType->getAs<EnumType>()) {
638	if (!ET->getDecl()->isComplete()) {
639	Diag(Loc, diag::err_objc_incomplete_boxed_expression_type)
640	<< ValueType << ValueExpr->getSourceRange();
641	return ExprError();
642	}
643
644	BoxingMethod = getNSNumberFactoryMethod(S&: *this, Loc,
645	NumberType: ET->getDecl()->getIntegerType());
646	BoxedType = NSNumberPointer;
647	} else if (ValueType->isObjCBoxableRecordType()) {
648	// Support for structure types, that marked as objc_boxable
649	// struct __attribute__((objc_boxable)) s { ... };
650
651	// Look up the NSValue class, if we haven't done so already. It's cached
652	// in the Sema instance.
653	if (!NSValueDecl) {
654	NSValueDecl = LookupObjCInterfaceDeclForLiteral(S&: *this, Loc,
655	LiteralKind: Sema::LK_Boxed);
656	if (!NSValueDecl) {
657	return ExprError();
658	}
659
660	// generate the pointer to NSValue type.
661	QualType NSValueObject = Context.getObjCInterfaceType(Decl: NSValueDecl);
662	NSValuePointer = Context.getObjCObjectPointerType(NSValueObject);
663	}
664
665	if (!ValueWithBytesObjCTypeMethod) {
666	const IdentifierInfo *II[] = {&Context.Idents.get(Name: "valueWithBytes"),
667	&Context.Idents.get(Name: "objCType")};
668	Selector ValueWithBytesObjCType = Context.Selectors.getSelector(NumArgs: 2, IIV: II);
669
670	// Look for the appropriate method within NSValue.
671	BoxingMethod = NSValueDecl->lookupClassMethod(Sel: ValueWithBytesObjCType);
672	if (!BoxingMethod && getLangOpts().DebuggerObjCLiteral) {
673	// Debugger needs to work even if NSValue hasn't been defined.
674	TypeSourceInfo *ReturnTInfo = nullptr;
675	ObjCMethodDecl *M = ObjCMethodDecl::Create(
676	Context, SourceLocation(), SourceLocation(), ValueWithBytesObjCType,
677	NSValuePointer, ReturnTInfo, NSValueDecl,
678	/*isInstance=*/false,
679	/*isVariadic=*/false,
680	/*isPropertyAccessor=*/false,
681	/*isSynthesizedAccessorStub=*/false,
682	/*isImplicitlyDeclared=*/true,
683	/*isDefined=*/false, ObjCImplementationControl::Required,
684	/*HasRelatedResultType=*/false);
685
686	SmallVector<ParmVarDecl *, 2> Params;
687
688	ParmVarDecl *bytes =
689	ParmVarDecl::Create(C&: Context, DC: M,
690	StartLoc: SourceLocation(), IdLoc: SourceLocation(),
691	Id: &Context.Idents.get(Name: "bytes"),
692	T: Context.VoidPtrTy.withConst(),
693	/*TInfo=*/nullptr,
694	S: SC_None, DefArg: nullptr);
695	Params.push_back(Elt: bytes);
696
697	QualType ConstCharType = Context.CharTy.withConst();
698	ParmVarDecl *type =
699	ParmVarDecl::Create(Context, M,
700	SourceLocation(), SourceLocation(),
701	&Context.Idents.get(Name: "type"),
702	Context.getPointerType(T: ConstCharType),
703	/*TInfo=*/nullptr,
704	SC_None, nullptr);
705	Params.push_back(Elt: type);
706
707	M->setMethodParams(C&: Context, Params, SelLocs: std::nullopt);
708	BoxingMethod = M;
709	}
710
711	if (!validateBoxingMethod(S&: *this, Loc, Class: NSValueDecl,
712	Sel: ValueWithBytesObjCType, Method: BoxingMethod))
713	return ExprError();
714
715	ValueWithBytesObjCTypeMethod = BoxingMethod;
716	}
717
718	if (!ValueType.isTriviallyCopyableType(Context)) {
719	Diag(Loc, diag::err_objc_non_trivially_copyable_boxed_expression_type)
720	<< ValueType << ValueExpr->getSourceRange();
721	return ExprError();
722	}
723
724	BoxingMethod = ValueWithBytesObjCTypeMethod;
725	BoxedType = NSValuePointer;
726	}
727
728	if (!BoxingMethod) {
729	Diag(Loc, diag::err_objc_illegal_boxed_expression_type)
730	<< ValueType << ValueExpr->getSourceRange();
731	return ExprError();
732	}
733
734	DiagnoseUseOfDecl(BoxingMethod, Loc);
735
736	ExprResult ConvertedValueExpr;
737	if (ValueType->isObjCBoxableRecordType()) {
738	InitializedEntity IE = InitializedEntity::InitializeTemporary(Type: ValueType);
739	ConvertedValueExpr = PerformCopyInitialization(Entity: IE, EqualLoc: ValueExpr->getExprLoc(),
740	Init: ValueExpr);
741	} else {
742	// Convert the expression to the type that the parameter requires.
743	ParmVarDecl *ParamDecl = BoxingMethod->parameters()[0];
744	InitializedEntity IE = InitializedEntity::InitializeParameter(Context,
745	Parm: ParamDecl);
746	ConvertedValueExpr = PerformCopyInitialization(Entity: IE, EqualLoc: SourceLocation(),
747	Init: ValueExpr);
748	}
749
750	if (ConvertedValueExpr.isInvalid())
751	return ExprError();
752	ValueExpr = ConvertedValueExpr.get();
753
754	ObjCBoxedExpr *BoxedExpr =
755	new (Context) ObjCBoxedExpr(ValueExpr, BoxedType,
756	BoxingMethod, SR);
757	return MaybeBindToTemporary(BoxedExpr);
758	}
759
760	/// Build an ObjC subscript pseudo-object expression, given that
761	/// that's supported by the runtime.
762	ExprResult Sema::BuildObjCSubscriptExpression(SourceLocation RB, Expr *BaseExpr,
763	Expr *IndexExpr,
764	ObjCMethodDecl *getterMethod,
765	ObjCMethodDecl *setterMethod) {
766	assert(!LangOpts.isSubscriptPointerArithmetic());
767
768	// We can't get dependent types here; our callers should have
769	// filtered them out.
770	assert((!BaseExpr->isTypeDependent() && !IndexExpr->isTypeDependent()) &&
771	"base or index cannot have dependent type here");
772
773	// Filter out placeholders in the index. In theory, overloads could
774	// be preserved here, although that might not actually work correctly.
775	ExprResult Result = CheckPlaceholderExpr(E: IndexExpr);
776	if (Result.isInvalid())
777	return ExprError();
778	IndexExpr = Result.get();
779
780	// Perform lvalue-to-rvalue conversion on the base.
781	Result = DefaultLvalueConversion(E: BaseExpr);
782	if (Result.isInvalid())
783	return ExprError();
784	BaseExpr = Result.get();
785
786	// Build the pseudo-object expression.
787	return new (Context) ObjCSubscriptRefExpr(
788	BaseExpr, IndexExpr, Context.PseudoObjectTy, VK_LValue, OK_ObjCSubscript,
789	getterMethod, setterMethod, RB);
790	}
791
792	ExprResult Sema::BuildObjCArrayLiteral(SourceRange SR, MultiExprArg Elements) {
793	SourceLocation Loc = SR.getBegin();
794
795	if (!NSArrayDecl) {
796	NSArrayDecl = LookupObjCInterfaceDeclForLiteral(S&: *this, Loc,
797	LiteralKind: Sema::LK_Array);
798	if (!NSArrayDecl) {
799	return ExprError();
800	}
801	}
802
803	// Find the arrayWithObjects:count: method, if we haven't done so already.
804	QualType IdT = Context.getObjCIdType();
805	if (!ArrayWithObjectsMethod) {
806	Selector
807	Sel = NSAPIObj->getNSArraySelector(MK: NSAPI::NSArr_arrayWithObjectsCount);
808	ObjCMethodDecl *Method = NSArrayDecl->lookupClassMethod(Sel);
809	if (!Method && getLangOpts().DebuggerObjCLiteral) {
810	TypeSourceInfo *ReturnTInfo = nullptr;
811	Method = ObjCMethodDecl::Create(
812	Context, SourceLocation(), SourceLocation(), Sel, IdT, ReturnTInfo,
813	Context.getTranslationUnitDecl(), false /*Instance*/,
814	false /*isVariadic*/,
815	/*isPropertyAccessor=*/false, /*isSynthesizedAccessorStub=*/false,
816	/*isImplicitlyDeclared=*/true, /*isDefined=*/false,
817	ObjCImplementationControl::Required, false);
818	SmallVector<ParmVarDecl *, 2> Params;
819	ParmVarDecl *objects = ParmVarDecl::Create(Context, Method,
820	SourceLocation(),
821	SourceLocation(),
822	&Context.Idents.get(Name: "objects"),
823	Context.getPointerType(T: IdT),
824	/*TInfo=*/nullptr,
825	SC_None, nullptr);
826	Params.push_back(Elt: objects);
827	ParmVarDecl *cnt = ParmVarDecl::Create(C&: Context, DC: Method,
828	StartLoc: SourceLocation(),
829	IdLoc: SourceLocation(),
830	Id: &Context.Idents.get(Name: "cnt"),
831	T: Context.UnsignedLongTy,
832	/*TInfo=*/nullptr, S: SC_None,
833	DefArg: nullptr);
834	Params.push_back(Elt: cnt);
835	Method->setMethodParams(C&: Context, Params, SelLocs: std::nullopt);
836	}
837
838	if (!validateBoxingMethod(S&: *this, Loc, Class: NSArrayDecl, Sel, Method))
839	return ExprError();
840
841	// Dig out the type that all elements should be converted to.
842	QualType T = Method->parameters()[0]->getType();
843	const PointerType *PtrT = T->getAs<PointerType>();
844	if (!PtrT ||
845	!Context.hasSameUnqualifiedType(T1: PtrT->getPointeeType(), T2: IdT)) {
846	Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
847	<< Sel;
848	Diag(Method->parameters()[0]->getLocation(),
849	diag::note_objc_literal_method_param)
850	<< 0 << T
851	<< Context.getPointerType(IdT.withConst());
852	return ExprError();
853	}
854
855	// Check that the 'count' parameter is integral.
856	if (!Method->parameters()[1]->getType()->isIntegerType()) {
857	Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
858	<< Sel;
859	Diag(Method->parameters()[1]->getLocation(),
860	diag::note_objc_literal_method_param)
861	<< 1
862	<< Method->parameters()[1]->getType()
863	<< "integral";
864	return ExprError();
865	}
866
867	// We've found a good +arrayWithObjects:count: method. Save it!
868	ArrayWithObjectsMethod = Method;
869	}
870
871	QualType ObjectsType = ArrayWithObjectsMethod->parameters()[0]->getType();
872	QualType RequiredType = ObjectsType->castAs<PointerType>()->getPointeeType();
873
874	// Check that each of the elements provided is valid in a collection literal,
875	// performing conversions as necessary.
876	Expr **ElementsBuffer = Elements.data();
877	for (unsigned I = 0, N = Elements.size(); I != N; ++I) {
878	ExprResult Converted = CheckObjCCollectionLiteralElement(S&: *this,
879	Element: ElementsBuffer[I],
880	T: RequiredType, ArrayLiteral: true);
881	if (Converted.isInvalid())
882	return ExprError();
883
884	ElementsBuffer[I] = Converted.get();
885	}
886
887	QualType Ty
888	= Context.getObjCObjectPointerType(
889	OIT: Context.getObjCInterfaceType(Decl: NSArrayDecl));
890
891	return MaybeBindToTemporary(
892	ObjCArrayLiteral::Create(C: Context, Elements, T: Ty,
893	Method: ArrayWithObjectsMethod, SR));
894	}
895
896	/// Check for duplicate keys in an ObjC dictionary literal. For instance:
897	/// NSDictionary *nd = @{ @"foo" : @"bar", @"foo" : @"baz" };
898	static void
899	CheckObjCDictionaryLiteralDuplicateKeys(Sema &S,
900	ObjCDictionaryLiteral *Literal) {
901	if (Literal->isValueDependent() || Literal->isTypeDependent())
902	return;
903
904	// NSNumber has quite relaxed equality semantics (for instance, @YES is
905	// considered equal to @1.0). For now, ignore floating points and just do a
906	// bit-width and sign agnostic integer compare.
907	struct APSIntCompare {
908	bool operator()(const llvm::APSInt &LHS, const llvm::APSInt &RHS) const {
909	return llvm::APSInt::compareValues(I1: LHS, I2: RHS) < 0;
910	}
911	};
912
913	llvm::DenseMap<StringRef, SourceLocation> StringKeys;
914	std::map<llvm::APSInt, SourceLocation, APSIntCompare> IntegralKeys;
915
916	auto checkOneKey = [&](auto &Map, const auto &Key, SourceLocation Loc) {
917	auto Pair = Map.insert({Key, Loc});
918	if (!Pair.second) {
919	S.Diag(Loc, diag::warn_nsdictionary_duplicate_key);
920	S.Diag(Pair.first->second, diag::note_nsdictionary_duplicate_key_here);
921	}
922	};
923
924	for (unsigned Idx = 0, End = Literal->getNumElements(); Idx != End; ++Idx) {
925	Expr *Key = Literal->getKeyValueElement(Index: Idx).Key->IgnoreParenImpCasts();
926
927	if (auto *StrLit = dyn_cast<ObjCStringLiteral>(Val: Key)) {
928	StringRef Bytes = StrLit->getString()->getBytes();
929	SourceLocation Loc = StrLit->getExprLoc();
930	checkOneKey(StringKeys, Bytes, Loc);
931	}
932
933	if (auto *BE = dyn_cast<ObjCBoxedExpr>(Val: Key)) {
934	Expr *Boxed = BE->getSubExpr();
935	SourceLocation Loc = BE->getExprLoc();
936
937	// Check for @("foo").
938	if (auto *Str = dyn_cast<StringLiteral>(Val: Boxed->IgnoreParenImpCasts())) {
939	checkOneKey(StringKeys, Str->getBytes(), Loc);
940	continue;
941	}
942
943	Expr::EvalResult Result;
944	if (Boxed->EvaluateAsInt(Result, Ctx: S.getASTContext(),
945	AllowSideEffects: Expr::SE_AllowSideEffects)) {
946	checkOneKey(IntegralKeys, Result.Val.getInt(), Loc);
947	}
948	}
949	}
950	}
951
952	ExprResult Sema::BuildObjCDictionaryLiteral(SourceRange SR,
953	MutableArrayRef<ObjCDictionaryElement> Elements) {
954	SourceLocation Loc = SR.getBegin();
955
956	if (!NSDictionaryDecl) {
957	NSDictionaryDecl = LookupObjCInterfaceDeclForLiteral(S&: *this, Loc,
958	LiteralKind: Sema::LK_Dictionary);
959	if (!NSDictionaryDecl) {
960	return ExprError();
961	}
962	}
963
964	// Find the dictionaryWithObjects:forKeys:count: method, if we haven't done
965	// so already.
966	QualType IdT = Context.getObjCIdType();
967	if (!DictionaryWithObjectsMethod) {
968	Selector Sel = NSAPIObj->getNSDictionarySelector(
969	MK: NSAPI::NSDict_dictionaryWithObjectsForKeysCount);
970	ObjCMethodDecl *Method = NSDictionaryDecl->lookupClassMethod(Sel);
971	if (!Method && getLangOpts().DebuggerObjCLiteral) {
972	Method = ObjCMethodDecl::Create(
973	Context, SourceLocation(), SourceLocation(), Sel, IdT,
974	nullptr /*TypeSourceInfo */, Context.getTranslationUnitDecl(),
975	false /*Instance*/, false /*isVariadic*/,
976	/*isPropertyAccessor=*/false,
977	/*isSynthesizedAccessorStub=*/false,
978	/*isImplicitlyDeclared=*/true, /*isDefined=*/false,
979	ObjCImplementationControl::Required, false);
980	SmallVector<ParmVarDecl *, 3> Params;
981	ParmVarDecl *objects = ParmVarDecl::Create(Context, Method,
982	SourceLocation(),
983	SourceLocation(),
984	&Context.Idents.get(Name: "objects"),
985	Context.getPointerType(T: IdT),
986	/*TInfo=*/nullptr, SC_None,
987	nullptr);
988	Params.push_back(Elt: objects);
989	ParmVarDecl *keys = ParmVarDecl::Create(Context, Method,
990	SourceLocation(),
991	SourceLocation(),
992	&Context.Idents.get(Name: "keys"),
993	Context.getPointerType(T: IdT),
994	/*TInfo=*/nullptr, SC_None,
995	nullptr);
996	Params.push_back(Elt: keys);
997	ParmVarDecl *cnt = ParmVarDecl::Create(C&: Context, DC: Method,
998	StartLoc: SourceLocation(),
999	IdLoc: SourceLocation(),
1000	Id: &Context.Idents.get(Name: "cnt"),
1001	T: Context.UnsignedLongTy,
1002	/*TInfo=*/nullptr, S: SC_None,
1003	DefArg: nullptr);
1004	Params.push_back(Elt: cnt);
1005	Method->setMethodParams(C&: Context, Params, SelLocs: std::nullopt);
1006	}
1007
1008	if (!validateBoxingMethod(S&: *this, Loc: SR.getBegin(), Class: NSDictionaryDecl, Sel,
1009	Method))
1010	return ExprError();
1011
1012	// Dig out the type that all values should be converted to.
1013	QualType ValueT = Method->parameters()[0]->getType();
1014	const PointerType *PtrValue = ValueT->getAs<PointerType>();
1015	if (!PtrValue ||
1016	!Context.hasSameUnqualifiedType(T1: PtrValue->getPointeeType(), T2: IdT)) {
1017	Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
1018	<< Sel;
1019	Diag(Method->parameters()[0]->getLocation(),
1020	diag::note_objc_literal_method_param)
1021	<< 0 << ValueT
1022	<< Context.getPointerType(IdT.withConst());
1023	return ExprError();
1024	}
1025
1026	// Dig out the type that all keys should be converted to.
1027	QualType KeyT = Method->parameters()[1]->getType();
1028	const PointerType *PtrKey = KeyT->getAs<PointerType>();
1029	if (!PtrKey ||
1030	!Context.hasSameUnqualifiedType(T1: PtrKey->getPointeeType(),
1031	T2: IdT)) {
1032	bool err = true;
1033	if (PtrKey) {
1034	if (QIDNSCopying.isNull()) {
1035	// key argument of selector is id<NSCopying>?
1036	if (ObjCProtocolDecl *NSCopyingPDecl =
1037	LookupProtocol(II: &Context.Idents.get(Name: "NSCopying"), IdLoc: SR.getBegin())) {
1038	ObjCProtocolDecl *PQ[] = {NSCopyingPDecl};
1039	QIDNSCopying = Context.getObjCObjectType(
1040	Context.ObjCBuiltinIdTy, {},
1041	llvm::ArrayRef((ObjCProtocolDecl **)PQ, 1), false);
1042	QIDNSCopying = Context.getObjCObjectPointerType(QIDNSCopying);
1043	}
1044	}
1045	if (!QIDNSCopying.isNull())
1046	err = !Context.hasSameUnqualifiedType(PtrKey->getPointeeType(),
1047	QIDNSCopying);
1048	}
1049
1050	if (err) {
1051	Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
1052	<< Sel;
1053	Diag(Method->parameters()[1]->getLocation(),
1054	diag::note_objc_literal_method_param)
1055	<< 1 << KeyT
1056	<< Context.getPointerType(IdT.withConst());
1057	return ExprError();
1058	}
1059	}
1060
1061	// Check that the 'count' parameter is integral.
1062	QualType CountType = Method->parameters()[2]->getType();
1063	if (!CountType->isIntegerType()) {
1064	Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
1065	<< Sel;
1066	Diag(Method->parameters()[2]->getLocation(),
1067	diag::note_objc_literal_method_param)
1068	<< 2 << CountType
1069	<< "integral";
1070	return ExprError();
1071	}
1072
1073	// We've found a good +dictionaryWithObjects:keys:count: method; save it!
1074	DictionaryWithObjectsMethod = Method;
1075	}
1076
1077	QualType ValuesT = DictionaryWithObjectsMethod->parameters()[0]->getType();
1078	QualType ValueT = ValuesT->castAs<PointerType>()->getPointeeType();
1079	QualType KeysT = DictionaryWithObjectsMethod->parameters()[1]->getType();
1080	QualType KeyT = KeysT->castAs<PointerType>()->getPointeeType();
1081
1082	// Check that each of the keys and values provided is valid in a collection
1083	// literal, performing conversions as necessary.
1084	bool HasPackExpansions = false;
1085	for (ObjCDictionaryElement &Element : Elements) {
1086	// Check the key.
1087	ExprResult Key = CheckObjCCollectionLiteralElement(S&: *this, Element: Element.Key,
1088	T: KeyT);
1089	if (Key.isInvalid())
1090	return ExprError();
1091
1092	// Check the value.
1093	ExprResult Value
1094	= CheckObjCCollectionLiteralElement(S&: *this, Element: Element.Value, T: ValueT);
1095	if (Value.isInvalid())
1096	return ExprError();
1097
1098	Element.Key = Key.get();
1099	Element.Value = Value.get();
1100
1101	if (Element.EllipsisLoc.isInvalid())
1102	continue;
1103
1104	if (!Element.Key->containsUnexpandedParameterPack() &&
1105	!Element.Value->containsUnexpandedParameterPack()) {
1106	Diag(Element.EllipsisLoc,
1107	diag::err_pack_expansion_without_parameter_packs)
1108	<< SourceRange(Element.Key->getBeginLoc(),
1109	Element.Value->getEndLoc());
1110	return ExprError();
1111	}
1112
1113	HasPackExpansions = true;
1114	}
1115
1116	QualType Ty = Context.getObjCObjectPointerType(
1117	OIT: Context.getObjCInterfaceType(Decl: NSDictionaryDecl));
1118
1119	auto *Literal =
1120	ObjCDictionaryLiteral::Create(C: Context, VK: Elements, HasPackExpansions, T: Ty,
1121	method: DictionaryWithObjectsMethod, SR);
1122	CheckObjCDictionaryLiteralDuplicateKeys(S&: *this, Literal);
1123	return MaybeBindToTemporary(Literal);
1124	}
1125
1126	ExprResult Sema::BuildObjCEncodeExpression(SourceLocation AtLoc,
1127	TypeSourceInfo *EncodedTypeInfo,
1128	SourceLocation RParenLoc) {
1129	QualType EncodedType = EncodedTypeInfo->getType();
1130	QualType StrTy;
1131	if (EncodedType->isDependentType())
1132	StrTy = Context.DependentTy;
1133	else {
1134	if (!EncodedType->getAsArrayTypeUnsafe() && //// Incomplete array is handled.
1135	!EncodedType->isVoidType()) // void is handled too.
1136	if (RequireCompleteType(AtLoc, EncodedType,
1137	diag::err_incomplete_type_objc_at_encode,
1138	EncodedTypeInfo->getTypeLoc()))
1139	return ExprError();
1140
1141	std::string Str;
1142	QualType NotEncodedT;
1143	Context.getObjCEncodingForType(T: EncodedType, S&: Str, Field: nullptr, NotEncodedT: &NotEncodedT);
1144	if (!NotEncodedT.isNull())
1145	Diag(AtLoc, diag::warn_incomplete_encoded_type)
1146	<< EncodedType << NotEncodedT;
1147
1148	// The type of @encode is the same as the type of the corresponding string,
1149	// which is an array type.
1150	StrTy = Context.getStringLiteralArrayType(EltTy: Context.CharTy, Length: Str.size());
1151	}
1152
1153	return new (Context) ObjCEncodeExpr(StrTy, EncodedTypeInfo, AtLoc, RParenLoc);
1154	}
1155
1156	ExprResult Sema::ParseObjCEncodeExpression(SourceLocation AtLoc,
1157	SourceLocation EncodeLoc,
1158	SourceLocation LParenLoc,
1159	ParsedType ty,
1160	SourceLocation RParenLoc) {
1161	// FIXME: Preserve type source info ?
1162	TypeSourceInfo *TInfo;
1163	QualType EncodedType = GetTypeFromParser(Ty: ty, TInfo: &TInfo);
1164	if (!TInfo)
1165	TInfo = Context.getTrivialTypeSourceInfo(T: EncodedType,
1166	Loc: getLocForEndOfToken(Loc: LParenLoc));
1167
1168	return BuildObjCEncodeExpression(AtLoc, EncodedTypeInfo: TInfo, RParenLoc);
1169	}
1170
1171	static bool HelperToDiagnoseMismatchedMethodsInGlobalPool(Sema &S,
1172	SourceLocation AtLoc,
1173	SourceLocation LParenLoc,
1174	SourceLocation RParenLoc,
1175	ObjCMethodDecl *Method,
1176	ObjCMethodList &MethList) {
1177	ObjCMethodList *M = &MethList;
1178	bool Warned = false;
1179	for (M = M->getNext(); M; M=M->getNext()) {
1180	ObjCMethodDecl *MatchingMethodDecl = M->getMethod();
1181	if (MatchingMethodDecl == Method ||
1182	isa<ObjCImplDecl>(MatchingMethodDecl->getDeclContext()) ||
1183	MatchingMethodDecl->getSelector() != Method->getSelector())
1184	continue;
1185	if (!S.MatchTwoMethodDeclarations(Method,
1186	PrevMethod: MatchingMethodDecl, strategy: Sema::MMS_loose)) {
1187	if (!Warned) {
1188	Warned = true;
1189	S.Diag(AtLoc, diag::warn_multiple_selectors)
1190	<< Method->getSelector() << FixItHint::CreateInsertion(LParenLoc, "(")
1191	<< FixItHint::CreateInsertion(RParenLoc, ")");
1192	S.Diag(Method->getLocation(), diag::note_method_declared_at)
1193	<< Method->getDeclName();
1194	}
1195	S.Diag(MatchingMethodDecl->getLocation(), diag::note_method_declared_at)
1196	<< MatchingMethodDecl->getDeclName();
1197	}
1198	}
1199	return Warned;
1200	}
1201
1202	static void DiagnoseMismatchedSelectors(Sema &S, SourceLocation AtLoc,
1203	ObjCMethodDecl *Method,
1204	SourceLocation LParenLoc,
1205	SourceLocation RParenLoc,
1206	bool WarnMultipleSelectors) {
1207	if (!WarnMultipleSelectors ||
1208	S.Diags.isIgnored(diag::warn_multiple_selectors, SourceLocation()))
1209	return;
1210	bool Warned = false;
1211	for (Sema::GlobalMethodPool::iterator b = S.MethodPool.begin(),
1212	e = S.MethodPool.end(); b != e; b++) {
1213	// first, instance methods
1214	ObjCMethodList &InstMethList = b->second.first;
1215	if (HelperToDiagnoseMismatchedMethodsInGlobalPool(S, AtLoc, LParenLoc, RParenLoc,
1216	Method, MethList&: InstMethList))
1217	Warned = true;
1218
1219	// second, class methods
1220	ObjCMethodList &ClsMethList = b->second.second;
1221	if (HelperToDiagnoseMismatchedMethodsInGlobalPool(S, AtLoc, LParenLoc, RParenLoc,
1222	Method, MethList&: ClsMethList) || Warned)
1223	return;
1224	}
1225	}
1226
1227	static ObjCMethodDecl *LookupDirectMethodInMethodList(Sema &S, Selector Sel,
1228	ObjCMethodList &MethList,
1229	bool &onlyDirect,
1230	bool &anyDirect) {
1231	(void)Sel;
1232	ObjCMethodList *M = &MethList;
1233	ObjCMethodDecl *DirectMethod = nullptr;
1234	for (; M; M = M->getNext()) {
1235	ObjCMethodDecl *Method = M->getMethod();
1236	if (!Method)
1237	continue;
1238	assert(Method->getSelector() == Sel && "Method with wrong selector in method list");
1239	if (Method->isDirectMethod()) {
1240	anyDirect = true;
1241	DirectMethod = Method;
1242	} else
1243	onlyDirect = false;
1244	}
1245
1246	return DirectMethod;
1247	}
1248
1249	// Search the global pool for (potentially) direct methods matching the given
1250	// selector. If a non-direct method is found, set \param onlyDirect to false. If
1251	// a direct method is found, set \param anyDirect to true. Returns a direct
1252	// method, if any.
1253	static ObjCMethodDecl *LookupDirectMethodInGlobalPool(Sema &S, Selector Sel,
1254	bool &onlyDirect,
1255	bool &anyDirect) {
1256	auto Iter = S.MethodPool.find(Sel);
1257	if (Iter == S.MethodPool.end())
1258	return nullptr;
1259
1260	ObjCMethodDecl *DirectInstance = LookupDirectMethodInMethodList(
1261	S, Sel, Iter->second.first, onlyDirect, anyDirect);
1262	ObjCMethodDecl *DirectClass = LookupDirectMethodInMethodList(
1263	S, Sel, Iter->second.second, onlyDirect, anyDirect);
1264
1265	return DirectInstance ? DirectInstance : DirectClass;
1266	}
1267
1268	static ObjCMethodDecl *findMethodInCurrentClass(Sema &S, Selector Sel) {
1269	auto *CurMD = S.getCurMethodDecl();
1270	if (!CurMD)
1271	return nullptr;
1272	ObjCInterfaceDecl *IFace = CurMD->getClassInterface();
1273
1274	// The language enforce that only one direct method is present in a given
1275	// class, so we just need to find one method in the current class to know
1276	// whether Sel is potentially direct in this context.
1277	if (ObjCMethodDecl *MD = IFace->lookupMethod(Sel, /*isInstance=*/true))
1278	return MD;
1279	if (ObjCMethodDecl *MD = IFace->lookupPrivateMethod(Sel, /*Instance=*/true))
1280	return MD;
1281	if (ObjCMethodDecl *MD = IFace->lookupMethod(Sel, /*isInstance=*/false))
1282	return MD;
1283	if (ObjCMethodDecl *MD = IFace->lookupPrivateMethod(Sel, /*Instance=*/false))
1284	return MD;
1285
1286	return nullptr;
1287	}
1288
1289	ExprResult Sema::ParseObjCSelectorExpression(Selector Sel,
1290	SourceLocation AtLoc,
1291	SourceLocation SelLoc,
1292	SourceLocation LParenLoc,
1293	SourceLocation RParenLoc,
1294	bool WarnMultipleSelectors) {
1295	ObjCMethodDecl *Method = LookupInstanceMethodInGlobalPool(Sel,
1296	R: SourceRange(LParenLoc, RParenLoc));
1297	if (!Method)
1298	Method = LookupFactoryMethodInGlobalPool(Sel,
1299	R: SourceRange(LParenLoc, RParenLoc));
1300	if (!Method) {
1301	if (const ObjCMethodDecl *OM = SelectorsForTypoCorrection(Sel)) {
1302	Selector MatchedSel = OM->getSelector();
1303	SourceRange SelectorRange(LParenLoc.getLocWithOffset(Offset: 1),
1304	RParenLoc.getLocWithOffset(Offset: -1));
1305	Diag(SelLoc, diag::warn_undeclared_selector_with_typo)
1306	<< Sel << MatchedSel
1307	<< FixItHint::CreateReplacement(SelectorRange, MatchedSel.getAsString());
1308
1309	} else
1310	Diag(SelLoc, diag::warn_undeclared_selector) << Sel;
1311	} else {
1312	DiagnoseMismatchedSelectors(S&: *this, AtLoc, Method, LParenLoc, RParenLoc,
1313	WarnMultipleSelectors);
1314
1315	bool onlyDirect = true;
1316	bool anyDirect = false;
1317	ObjCMethodDecl *GlobalDirectMethod =
1318	LookupDirectMethodInGlobalPool(S&: *this, Sel, onlyDirect, anyDirect);
1319
1320	if (onlyDirect) {
1321	Diag(AtLoc, diag::err_direct_selector_expression)
1322	<< Method->getSelector();
1323	Diag(Method->getLocation(), diag::note_direct_method_declared_at)
1324	<< Method->getDeclName();
1325	} else if (anyDirect) {
1326	// If we saw any direct methods, see if we see a direct member of the
1327	// current class. If so, the @selector will likely be used to refer to
1328	// this direct method.
1329	ObjCMethodDecl *LikelyTargetMethod = findMethodInCurrentClass(S&: *this, Sel);
1330	if (LikelyTargetMethod && LikelyTargetMethod->isDirectMethod()) {
1331	Diag(AtLoc, diag::warn_potentially_direct_selector_expression) << Sel;
1332	Diag(LikelyTargetMethod->getLocation(),
1333	diag::note_direct_method_declared_at)
1334	<< LikelyTargetMethod->getDeclName();
1335	} else if (!LikelyTargetMethod) {
1336	// Otherwise, emit the "strict" variant of this diagnostic, unless
1337	// LikelyTargetMethod is non-direct.
1338	Diag(AtLoc, diag::warn_strict_potentially_direct_selector_expression)
1339	<< Sel;
1340	Diag(GlobalDirectMethod->getLocation(),
1341	diag::note_direct_method_declared_at)
1342	<< GlobalDirectMethod->getDeclName();
1343	}
1344	}
1345	}
1346
1347	if (Method &&
1348	Method->getImplementationControl() !=
1349	ObjCImplementationControl::Optional &&
1350	!getSourceManager().isInSystemHeader(Loc: Method->getLocation()))
1351	ReferencedSelectors.insert(KV: std::make_pair(x&: Sel, y&: AtLoc));
1352
1353	// In ARC, forbid the user from using @selector for
1354	// retain/release/autorelease/dealloc/retainCount.
1355	if (getLangOpts().ObjCAutoRefCount) {
1356	switch (Sel.getMethodFamily()) {
1357	case OMF_retain:
1358	case OMF_release:
1359	case OMF_autorelease:
1360	case OMF_retainCount:
1361	case OMF_dealloc:
1362	Diag(AtLoc, diag::err_arc_illegal_selector) <<
1363	Sel << SourceRange(LParenLoc, RParenLoc);
1364	break;
1365
1366	case OMF_None:
1367	case OMF_alloc:
1368	case OMF_copy:
1369	case OMF_finalize:
1370	case OMF_init:
1371	case OMF_mutableCopy:
1372	case OMF_new:
1373	case OMF_self:
1374	case OMF_initialize:
1375	case OMF_performSelector:
1376	break;
1377	}
1378	}
1379	QualType Ty = Context.getObjCSelType();
1380	return new (Context) ObjCSelectorExpr(Ty, Sel, AtLoc, RParenLoc);
1381	}
1382
1383	ExprResult Sema::ParseObjCProtocolExpression(IdentifierInfo *ProtocolId,
1384	SourceLocation AtLoc,
1385	SourceLocation ProtoLoc,
1386	SourceLocation LParenLoc,
1387	SourceLocation ProtoIdLoc,
1388	SourceLocation RParenLoc) {
1389	ObjCProtocolDecl* PDecl = LookupProtocol(II: ProtocolId, IdLoc: ProtoIdLoc);
1390	if (!PDecl) {
1391	Diag(ProtoLoc, diag::err_undeclared_protocol) << ProtocolId;
1392	return true;
1393	}
1394	if (PDecl->isNonRuntimeProtocol())
1395	Diag(ProtoLoc, diag::err_objc_non_runtime_protocol_in_protocol_expr)
1396	<< PDecl;
1397	if (!PDecl->hasDefinition()) {
1398	Diag(ProtoLoc, diag::err_atprotocol_protocol) << PDecl;
1399	Diag(PDecl->getLocation(), diag::note_entity_declared_at) << PDecl;
1400	} else {
1401	PDecl = PDecl->getDefinition();
1402	}
1403
1404	QualType Ty = Context.getObjCProtoType();
1405	if (Ty.isNull())
1406	return true;
1407	Ty = Context.getObjCObjectPointerType(OIT: Ty);
1408	return new (Context) ObjCProtocolExpr(Ty, PDecl, AtLoc, ProtoIdLoc, RParenLoc);
1409	}
1410
1411	/// Try to capture an implicit reference to 'self'.
1412	ObjCMethodDecl *Sema::tryCaptureObjCSelf(SourceLocation Loc) {
1413	DeclContext *DC = getFunctionLevelDeclContext();
1414
1415	// If we're not in an ObjC method, error out. Note that, unlike the
1416	// C++ case, we don't require an instance method --- class methods
1417	// still have a 'self', and we really do still need to capture it!
1418	ObjCMethodDecl *method = dyn_cast<ObjCMethodDecl>(Val: DC);
1419	if (!method)
1420	return nullptr;
1421
1422	tryCaptureVariable(method->getSelfDecl(), Loc);
1423
1424	return method;
1425	}
1426
1427	static QualType stripObjCInstanceType(ASTContext &Context, QualType T) {
1428	QualType origType = T;
1429	if (auto nullability = AttributedType::stripOuterNullability(T)) {
1430	if (T == Context.getObjCInstanceType()) {
1431	return Context.getAttributedType(
1432	attrKind: AttributedType::getNullabilityAttrKind(kind: *nullability),
1433	modifiedType: Context.getObjCIdType(),
1434	equivalentType: Context.getObjCIdType());
1435	}
1436
1437	return origType;
1438	}
1439
1440	if (T == Context.getObjCInstanceType())
1441	return Context.getObjCIdType();
1442
1443	return origType;
1444	}
1445
1446	/// Determine the result type of a message send based on the receiver type,
1447	/// method, and the kind of message send.
1448	///
1449	/// This is the "base" result type, which will still need to be adjusted
1450	/// to account for nullability.
1451	static QualType getBaseMessageSendResultType(Sema &S,
1452	QualType ReceiverType,
1453	ObjCMethodDecl *Method,
1454	bool isClassMessage,
1455	bool isSuperMessage) {
1456	assert(Method && "Must have a method");
1457	if (!Method->hasRelatedResultType())
1458	return Method->getSendResultType(receiverType: ReceiverType);
1459
1460	ASTContext &Context = S.Context;
1461
1462	// Local function that transfers the nullability of the method's
1463	// result type to the returned result.
1464	auto transferNullability = [&](QualType type) -> QualType {
1465	// If the method's result type has nullability, extract it.
1466	if (auto nullability =
1467	Method->getSendResultType(receiverType: ReceiverType)->getNullability()) {
1468	// Strip off any outer nullability sugar from the provided type.
1469	(void)AttributedType::stripOuterNullability(T&: type);
1470
1471	// Form a new attributed type using the method result type's nullability.
1472	return Context.getAttributedType(
1473	attrKind: AttributedType::getNullabilityAttrKind(kind: *nullability),
1474	modifiedType: type,
1475	equivalentType: type);
1476	}
1477
1478	return type;
1479	};
1480
1481	// If a method has a related return type:
1482	// - if the method found is an instance method, but the message send
1483	// was a class message send, T is the declared return type of the method
1484	// found
1485	if (Method->isInstanceMethod() && isClassMessage)
1486	return stripObjCInstanceType(Context,
1487	T: Method->getSendResultType(receiverType: ReceiverType));
1488
1489	// - if the receiver is super, T is a pointer to the class of the
1490	// enclosing method definition
1491	if (isSuperMessage) {
1492	if (ObjCMethodDecl *CurMethod = S.getCurMethodDecl())
1493	if (ObjCInterfaceDecl *Class = CurMethod->getClassInterface()) {
1494	return transferNullability(
1495	Context.getObjCObjectPointerType(
1496	OIT: Context.getObjCInterfaceType(Decl: Class)));
1497	}
1498	}
1499
1500	// - if the receiver is the name of a class U, T is a pointer to U
1501	if (ReceiverType->getAsObjCInterfaceType())
1502	return transferNullability(Context.getObjCObjectPointerType(OIT: ReceiverType));
1503	// - if the receiver is of type Class or qualified Class type,
1504	// T is the declared return type of the method.
1505	if (ReceiverType->isObjCClassType() ||
1506	ReceiverType->isObjCQualifiedClassType())
1507	return stripObjCInstanceType(Context,
1508	T: Method->getSendResultType(receiverType: ReceiverType));
1509
1510	// - if the receiver is id, qualified id, Class, or qualified Class, T
1511	// is the receiver type, otherwise
1512	// - T is the type of the receiver expression.
1513	return transferNullability(ReceiverType);
1514	}
1515
1516	QualType Sema::getMessageSendResultType(const Expr *Receiver,
1517	QualType ReceiverType,
1518	ObjCMethodDecl *Method,
1519	bool isClassMessage,
1520	bool isSuperMessage) {
1521	// Produce the result type.
1522	QualType resultType = getBaseMessageSendResultType(S&: *this, ReceiverType,
1523	Method,
1524	isClassMessage,
1525	isSuperMessage);
1526
1527	// If this is a class message, ignore the nullability of the receiver.
1528	if (isClassMessage) {
1529	// In a class method, class messages to 'self' that return instancetype can
1530	// be typed as the current class. We can safely do this in ARC because self
1531	// can't be reassigned, and we do it unsafely outside of ARC because in
1532	// practice people never reassign self in class methods and there's some
1533	// virtue in not being aggressively pedantic.
1534	if (Receiver && Receiver->isObjCSelfExpr()) {
1535	assert(ReceiverType->isObjCClassType() && "expected a Class self");
1536	QualType T = Method->getSendResultType(receiverType: ReceiverType);
1537	AttributedType::stripOuterNullability(T);
1538	if (T == Context.getObjCInstanceType()) {
1539	const ObjCMethodDecl *MD = cast<ObjCMethodDecl>(
1540	cast<ImplicitParamDecl>(
1541	Val: cast<DeclRefExpr>(Val: Receiver->IgnoreParenImpCasts())->getDecl())
1542	->getDeclContext());
1543	assert(MD->isClassMethod() && "expected a class method");
1544	QualType NewResultType = Context.getObjCObjectPointerType(
1545	OIT: Context.getObjCInterfaceType(Decl: MD->getClassInterface()));
1546	if (auto Nullability = resultType->getNullability())
1547	NewResultType = Context.getAttributedType(
1548	attrKind: AttributedType::getNullabilityAttrKind(kind: *Nullability),
1549	modifiedType: NewResultType, equivalentType: NewResultType);
1550	return NewResultType;
1551	}
1552	}
1553	return resultType;
1554	}
1555
1556	// There is nothing left to do if the result type cannot have a nullability
1557	// specifier.
1558	if (!resultType->canHaveNullability())
1559	return resultType;
1560
1561	// Map the nullability of the result into a table index.
1562	unsigned receiverNullabilityIdx = 0;
1563	if (std::optional<NullabilityKind> nullability =
1564	ReceiverType->getNullability()) {
1565	if (*nullability == NullabilityKind::NullableResult)
1566	nullability = NullabilityKind::Nullable;
1567	receiverNullabilityIdx = 1 + static_cast<unsigned>(*nullability);
1568	}
1569
1570	unsigned resultNullabilityIdx = 0;
1571	if (std::optional<NullabilityKind> nullability =
1572	resultType->getNullability()) {
1573	if (*nullability == NullabilityKind::NullableResult)
1574	nullability = NullabilityKind::Nullable;
1575	resultNullabilityIdx = 1 + static_cast<unsigned>(*nullability);
1576	}
1577
1578	// The table of nullability mappings, indexed by the receiver's nullability
1579	// and then the result type's nullability.
1580	static const uint8_t None = 0;
1581	static const uint8_t NonNull = 1;
1582	static const uint8_t Nullable = 2;
1583	static const uint8_t Unspecified = 3;
1584	static const uint8_t nullabilityMap[4][4] = {
1585	// None NonNull Nullable Unspecified
1586	/* None */ { None, None, Nullable, None },
1587	/* NonNull */ { None, NonNull, Nullable, Unspecified },
1588	/* Nullable */ { Nullable, Nullable, Nullable, Nullable },
1589	/* Unspecified */ { None, Unspecified, Nullable, Unspecified }
1590	};
1591
1592	unsigned newResultNullabilityIdx
1593	= nullabilityMap[receiverNullabilityIdx][resultNullabilityIdx];
1594	if (newResultNullabilityIdx == resultNullabilityIdx)
1595	return resultType;
1596
1597	// Strip off the existing nullability. This removes as little type sugar as
1598	// possible.
1599	do {
1600	if (auto attributed = dyn_cast<AttributedType>(Val: resultType.getTypePtr())) {
1601	resultType = attributed->getModifiedType();
1602	} else {
1603	resultType = resultType.getDesugaredType(Context);
1604	}
1605	} while (resultType->getNullability());
1606
1607	// Add nullability back if needed.
1608	if (newResultNullabilityIdx > 0) {
1609	auto newNullability
1610	= static_cast<NullabilityKind>(newResultNullabilityIdx-1);
1611	return Context.getAttributedType(
1612	attrKind: AttributedType::getNullabilityAttrKind(kind: newNullability),
1613	modifiedType: resultType, equivalentType: resultType);
1614	}
1615
1616	return resultType;
1617	}
1618
1619	/// Look for an ObjC method whose result type exactly matches the given type.
1620	static const ObjCMethodDecl *
1621	findExplicitInstancetypeDeclarer(const ObjCMethodDecl *MD,
1622	QualType instancetype) {
1623	if (MD->getReturnType() == instancetype)
1624	return MD;
1625
1626	// For these purposes, a method in an @implementation overrides a
1627	// declaration in the @interface.
1628	if (const ObjCImplDecl *impl =
1629	dyn_cast<ObjCImplDecl>(MD->getDeclContext())) {
1630	const ObjCContainerDecl *iface;
1631	if (const ObjCCategoryImplDecl *catImpl =
1632	dyn_cast<ObjCCategoryImplDecl>(Val: impl)) {
1633	iface = catImpl->getCategoryDecl();
1634	} else {
1635	iface = impl->getClassInterface();
1636	}
1637
1638	const ObjCMethodDecl *ifaceMD =
1639	iface->getMethod(Sel: MD->getSelector(), isInstance: MD->isInstanceMethod());
1640	if (ifaceMD) return findExplicitInstancetypeDeclarer(MD: ifaceMD, instancetype);
1641	}
1642
1643	SmallVector<const ObjCMethodDecl *, 4> overrides;
1644	MD->getOverriddenMethods(Overridden&: overrides);
1645	for (unsigned i = 0, e = overrides.size(); i != e; ++i) {
1646	if (const ObjCMethodDecl *result =
1647	findExplicitInstancetypeDeclarer(MD: overrides[i], instancetype))
1648	return result;
1649	}
1650
1651	return nullptr;
1652	}
1653
1654	void Sema::EmitRelatedResultTypeNoteForReturn(QualType destType) {
1655	// Only complain if we're in an ObjC method and the required return
1656	// type doesn't match the method's declared return type.
1657	ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(Val: CurContext);
1658	if (!MD || !MD->hasRelatedResultType() ||
1659	Context.hasSameUnqualifiedType(T1: destType, T2: MD->getReturnType()))
1660	return;
1661
1662	// Look for a method overridden by this method which explicitly uses
1663	// 'instancetype'.
1664	if (const ObjCMethodDecl *overridden =
1665	findExplicitInstancetypeDeclarer(MD, instancetype: Context.getObjCInstanceType())) {
1666	SourceRange range = overridden->getReturnTypeSourceRange();
1667	SourceLocation loc = range.getBegin();
1668	if (loc.isInvalid())
1669	loc = overridden->getLocation();
1670	Diag(loc, diag::note_related_result_type_explicit)
1671	<< /*current method*/ 1 << range;
1672	return;
1673	}
1674
1675	// Otherwise, if we have an interesting method family, note that.
1676	// This should always trigger if the above didn't.
1677	if (ObjCMethodFamily family = MD->getMethodFamily())
1678	Diag(MD->getLocation(), diag::note_related_result_type_family)
1679	<< /*current method*/ 1
1680	<< family;
1681	}
1682
1683	void Sema::EmitRelatedResultTypeNote(const Expr *E) {
1684	E = E->IgnoreParenImpCasts();
1685	const ObjCMessageExpr *MsgSend = dyn_cast<ObjCMessageExpr>(Val: E);
1686	if (!MsgSend)
1687	return;
1688
1689	const ObjCMethodDecl *Method = MsgSend->getMethodDecl();
1690	if (!Method)
1691	return;
1692
1693	if (!Method->hasRelatedResultType())
1694	return;
1695
1696	if (Context.hasSameUnqualifiedType(
1697	T1: Method->getReturnType().getNonReferenceType(), T2: MsgSend->getType()))
1698	return;
1699
1700	if (!Context.hasSameUnqualifiedType(T1: Method->getReturnType(),
1701	T2: Context.getObjCInstanceType()))
1702	return;
1703
1704	Diag(Method->getLocation(), diag::note_related_result_type_inferred)
1705	<< Method->isInstanceMethod() << Method->getSelector()
1706	<< MsgSend->getType();
1707	}
1708
1709	bool Sema::CheckMessageArgumentTypes(
1710	const Expr *Receiver, QualType ReceiverType, MultiExprArg Args,
1711	Selector Sel, ArrayRef<SourceLocation> SelectorLocs, ObjCMethodDecl *Method,
1712	bool isClassMessage, bool isSuperMessage, SourceLocation lbrac,
1713	SourceLocation rbrac, SourceRange RecRange, QualType &ReturnType,
1714	ExprValueKind &VK) {
1715	SourceLocation SelLoc;
1716	if (!SelectorLocs.empty() && SelectorLocs.front().isValid())
1717	SelLoc = SelectorLocs.front();
1718	else
1719	SelLoc = lbrac;
1720
1721	if (!Method) {
1722	// Apply default argument promotion as for (C99 6.5.2.2p6).
1723	for (unsigned i = 0, e = Args.size(); i != e; i++) {
1724	if (Args[i]->isTypeDependent())
1725	continue;
1726
1727	ExprResult result;
1728	if (getLangOpts().DebuggerSupport) {
1729	QualType paramTy; // ignored
1730	result = checkUnknownAnyArg(callLoc: SelLoc, result: Args[i], paramType&: paramTy);
1731	} else {
1732	result = DefaultArgumentPromotion(E: Args[i]);
1733	}
1734	if (result.isInvalid())
1735	return true;
1736	Args[i] = result.get();
1737	}
1738
1739	unsigned DiagID;
1740	if (getLangOpts().ObjCAutoRefCount)
1741	DiagID = diag::err_arc_method_not_found;
1742	else
1743	DiagID = isClassMessage ? diag::warn_class_method_not_found
1744	: diag::warn_inst_method_not_found;
1745	if (!getLangOpts().DebuggerSupport) {
1746	const ObjCMethodDecl *OMD = SelectorsForTypoCorrection(Sel, ObjectType: ReceiverType);
1747	if (OMD && !OMD->isInvalidDecl()) {
1748	if (getLangOpts().ObjCAutoRefCount)
1749	DiagID = diag::err_method_not_found_with_typo;
1750	else
1751	DiagID = isClassMessage ? diag::warn_class_method_not_found_with_typo
1752	: diag::warn_instance_method_not_found_with_typo;
1753	Selector MatchedSel = OMD->getSelector();
1754	SourceRange SelectorRange(SelectorLocs.front(), SelectorLocs.back());
1755	if (MatchedSel.isUnarySelector())
1756	Diag(SelLoc, DiagID)
1757	<< Sel<< isClassMessage << MatchedSel
1758	<< FixItHint::CreateReplacement(RemoveRange: SelectorRange, Code: MatchedSel.getAsString());
1759	else
1760	Diag(SelLoc, DiagID) << Sel<< isClassMessage << MatchedSel;
1761	}
1762	else
1763	Diag(SelLoc, DiagID)
1764	<< Sel << isClassMessage << SourceRange(SelectorLocs.front(),
1765	SelectorLocs.back());
1766	// Find the class to which we are sending this message.
1767	if (auto *ObjPT = ReceiverType->getAs<ObjCObjectPointerType>()) {
1768	if (ObjCInterfaceDecl *ThisClass = ObjPT->getInterfaceDecl()) {
1769	Diag(ThisClass->getLocation(), diag::note_receiver_class_declared);
1770	if (!RecRange.isInvalid())
1771	if (ThisClass->lookupClassMethod(Sel))
1772	Diag(RecRange.getBegin(), diag::note_receiver_expr_here)
1773	<< FixItHint::CreateReplacement(RecRange,
1774	ThisClass->getNameAsString());
1775	}
1776	}
1777	}
1778
1779	// In debuggers, we want to use __unknown_anytype for these
1780	// results so that clients can cast them.
1781	if (getLangOpts().DebuggerSupport) {
1782	ReturnType = Context.UnknownAnyTy;
1783	} else {
1784	ReturnType = Context.getObjCIdType();
1785	}
1786	VK = VK_PRValue;
1787	return false;
1788	}
1789
1790	ReturnType = getMessageSendResultType(Receiver, ReceiverType, Method,
1791	isClassMessage, isSuperMessage);
1792	VK = Expr::getValueKindForType(T: Method->getReturnType());
1793
1794	unsigned NumNamedArgs = Sel.getNumArgs();
1795	// Method might have more arguments than selector indicates. This is due
1796	// to addition of c-style arguments in method.
1797	if (Method->param_size() > Sel.getNumArgs())
1798	NumNamedArgs = Method->param_size();
1799	// FIXME. This need be cleaned up.
1800	if (Args.size() < NumNamedArgs) {
1801	Diag(SelLoc, diag::err_typecheck_call_too_few_args)
1802	<< 2 << NumNamedArgs << static_cast<unsigned>(Args.size())
1803	<< /*is non object*/ 0;
1804	return false;
1805	}
1806
1807	// Compute the set of type arguments to be substituted into each parameter
1808	// type.
1809	std::optional<ArrayRef<QualType>> typeArgs =
1810	ReceiverType->getObjCSubstitutions(dc: Method->getDeclContext());
1811	bool IsError = false;
1812	for (unsigned i = 0; i < NumNamedArgs; i++) {
1813	// We can't do any type-checking on a type-dependent argument.
1814	if (Args[i]->isTypeDependent())
1815	continue;
1816
1817	Expr *argExpr = Args[i];
1818
1819	ParmVarDecl *param = Method->parameters()[i];
1820	assert(argExpr && "CheckMessageArgumentTypes(): missing expression");
1821
1822	if (param->hasAttr<NoEscapeAttr>() &&
1823	param->getType()->isBlockPointerType())
1824	if (auto *BE = dyn_cast<BlockExpr>(
1825	Val: argExpr->IgnoreParenNoopCasts(Ctx: Context)))
1826	BE->getBlockDecl()->setDoesNotEscape();
1827
1828	// Strip the unbridged-cast placeholder expression off unless it's
1829	// a consumed argument.
1830	if (argExpr->hasPlaceholderType(BuiltinType::ARCUnbridgedCast) &&
1831	!param->hasAttr<CFConsumedAttr>())
1832	argExpr = stripARCUnbridgedCast(e: argExpr);
1833
1834	// If the parameter is __unknown_anytype, infer its type
1835	// from the argument.
1836	if (param->getType() == Context.UnknownAnyTy) {
1837	QualType paramType;
1838	ExprResult argE = checkUnknownAnyArg(callLoc: SelLoc, result: argExpr, paramType);
1839	if (argE.isInvalid()) {
1840	IsError = true;
1841	} else {
1842	Args[i] = argE.get();
1843
1844	// Update the parameter type in-place.
1845	param->setType(paramType);
1846	}
1847	continue;
1848	}
1849
1850	QualType origParamType = param->getType();
1851	QualType paramType = param->getType();
1852	if (typeArgs)
1853	paramType = paramType.substObjCTypeArgs(
1854	ctx&: Context,
1855	typeArgs: *typeArgs,
1856	context: ObjCSubstitutionContext::Parameter);
1857
1858	if (RequireCompleteType(argExpr->getSourceRange().getBegin(),
1859	paramType,
1860	diag::err_call_incomplete_argument, argExpr))
1861	return true;
1862
1863	InitializedEntity Entity
1864	= InitializedEntity::InitializeParameter(Context, Parm: param, Type: paramType);
1865	ExprResult ArgE = PerformCopyInitialization(Entity, EqualLoc: SourceLocation(), Init: argExpr);
1866	if (ArgE.isInvalid())
1867	IsError = true;
1868	else {
1869	Args[i] = ArgE.getAs<Expr>();
1870
1871	// If we are type-erasing a block to a block-compatible
1872	// Objective-C pointer type, we may need to extend the lifetime
1873	// of the block object.
1874	if (typeArgs && Args[i]->isPRValue() && paramType->isBlockPointerType() &&
1875	Args[i]->getType()->isBlockPointerType() &&
1876	origParamType->isObjCObjectPointerType()) {
1877	ExprResult arg = Args[i];
1878	maybeExtendBlockObject(E&: arg);
1879	Args[i] = arg.get();
1880	}
1881	}
1882	}
1883
1884	// Promote additional arguments to variadic methods.
1885	if (Method->isVariadic()) {
1886	for (unsigned i = NumNamedArgs, e = Args.size(); i < e; ++i) {
1887	if (Args[i]->isTypeDependent())
1888	continue;
1889
1890	ExprResult Arg = DefaultVariadicArgumentPromotion(E: Args[i], CT: VariadicMethod,
1891	FDecl: nullptr);
1892	IsError |= Arg.isInvalid();
1893	Args[i] = Arg.get();
1894	}
1895	} else {
1896	// Check for extra arguments to non-variadic methods.
1897	if (Args.size() != NumNamedArgs) {
1898	Diag(Args[NumNamedArgs]->getBeginLoc(),
1899	diag::err_typecheck_call_too_many_args)
1900	<< 2 /*method*/ << NumNamedArgs << static_cast<unsigned>(Args.size())
1901	<< Method->getSourceRange() << /*is non object*/ 0
1902	<< SourceRange(Args[NumNamedArgs]->getBeginLoc(),
1903	Args.back()->getEndLoc());
1904	}
1905	}
1906
1907	DiagnoseSentinelCalls(Method, SelLoc, Args);
1908
1909	// Do additional checkings on method.
1910	IsError |=
1911	CheckObjCMethodCall(Method, loc: SelLoc, Args: ArrayRef(Args.data(), Args.size()));
1912
1913	return IsError;
1914	}
1915
1916	bool Sema::isSelfExpr(Expr *RExpr) {
1917	// 'self' is objc 'self' in an objc method only.
1918	ObjCMethodDecl *Method =
1919	dyn_cast_or_null<ObjCMethodDecl>(Val: CurContext->getNonClosureAncestor());
1920	return isSelfExpr(RExpr, Method);
1921	}
1922
1923	bool Sema::isSelfExpr(Expr *receiver, const ObjCMethodDecl *method) {
1924	if (!method) return false;
1925
1926	receiver = receiver->IgnoreParenLValueCasts();
1927	if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Val: receiver))
1928	if (DRE->getDecl() == method->getSelfDecl())
1929	return true;
1930	return false;
1931	}
1932
1933	/// LookupMethodInType - Look up a method in an ObjCObjectType.
1934	ObjCMethodDecl *Sema::LookupMethodInObjectType(Selector sel, QualType type,
1935	bool isInstance) {
1936	const ObjCObjectType *objType = type->castAs<ObjCObjectType>();
1937	if (ObjCInterfaceDecl *iface = objType->getInterface()) {
1938	// Look it up in the main interface (and categories, etc.)
1939	if (ObjCMethodDecl *method = iface->lookupMethod(Sel: sel, isInstance))
1940	return method;
1941
1942	// Okay, look for "private" methods declared in any
1943	// @implementations we've seen.
1944	if (ObjCMethodDecl *method = iface->lookupPrivateMethod(Sel: sel, Instance: isInstance))
1945	return method;
1946	}
1947
1948	// Check qualifiers.
1949	for (const auto *I : objType->quals())
1950	if (ObjCMethodDecl *method = I->lookupMethod(sel, isInstance))
1951	return method;
1952
1953	return nullptr;
1954	}
1955
1956	/// LookupMethodInQualifiedType - Lookups up a method in protocol qualifier
1957	/// list of a qualified objective pointer type.
1958	ObjCMethodDecl *Sema::LookupMethodInQualifiedType(Selector Sel,
1959	const ObjCObjectPointerType *OPT,
1960	bool Instance)
1961	{
1962	ObjCMethodDecl *MD = nullptr;
1963	for (const auto *PROTO : OPT->quals()) {
1964	if ((MD = PROTO->lookupMethod(Sel, Instance))) {
1965	return MD;
1966	}
1967	}
1968	return nullptr;
1969	}
1970
1971	/// HandleExprPropertyRefExpr - Handle foo.bar where foo is a pointer to an
1972	/// objective C interface. This is a property reference expression.
1973	ExprResult Sema::
1974	HandleExprPropertyRefExpr(const ObjCObjectPointerType *OPT,
1975	Expr *BaseExpr, SourceLocation OpLoc,
1976	DeclarationName MemberName,
1977	SourceLocation MemberLoc,
1978	SourceLocation SuperLoc, QualType SuperType,
1979	bool Super) {
1980	const ObjCInterfaceType *IFaceT = OPT->getInterfaceType();
1981	ObjCInterfaceDecl *IFace = IFaceT->getDecl();
1982
1983	if (!MemberName.isIdentifier()) {
1984	Diag(MemberLoc, diag::err_invalid_property_name)
1985	<< MemberName << QualType(OPT, 0);
1986	return ExprError();
1987	}
1988
1989	IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
1990
1991	SourceRange BaseRange = Super? SourceRange(SuperLoc)
1992	: BaseExpr->getSourceRange();
1993	if (RequireCompleteType(MemberLoc, OPT->getPointeeType(),
1994	diag::err_property_not_found_forward_class,
1995	MemberName, BaseRange))
1996	return ExprError();
1997
1998	if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(
1999	Member, ObjCPropertyQueryKind::OBJC_PR_query_instance)) {
2000	// Check whether we can reference this property.
2001	if (DiagnoseUseOfDecl(PD, MemberLoc))
2002	return ExprError();
2003	if (Super)
2004	return new (Context)
2005	ObjCPropertyRefExpr(PD, Context.PseudoObjectTy, VK_LValue,
2006	OK_ObjCProperty, MemberLoc, SuperLoc, SuperType);
2007	else
2008	return new (Context)
2009	ObjCPropertyRefExpr(PD, Context.PseudoObjectTy, VK_LValue,
2010	OK_ObjCProperty, MemberLoc, BaseExpr);
2011	}
2012	// Check protocols on qualified interfaces.
2013	for (const auto *I : OPT->quals())
2014	if (ObjCPropertyDecl *PD = I->FindPropertyDeclaration(
2015	Member, ObjCPropertyQueryKind::OBJC_PR_query_instance)) {
2016	// Check whether we can reference this property.
2017	if (DiagnoseUseOfDecl(PD, MemberLoc))
2018	return ExprError();
2019
2020	if (Super)
2021	return new (Context) ObjCPropertyRefExpr(
2022	PD, Context.PseudoObjectTy, VK_LValue, OK_ObjCProperty, MemberLoc,
2023	SuperLoc, SuperType);
2024	else
2025	return new (Context)
2026	ObjCPropertyRefExpr(PD, Context.PseudoObjectTy, VK_LValue,
2027	OK_ObjCProperty, MemberLoc, BaseExpr);
2028	}
2029	// If that failed, look for an "implicit" property by seeing if the nullary
2030	// selector is implemented.
2031
2032	// FIXME: The logic for looking up nullary and unary selectors should be
2033	// shared with the code in ActOnInstanceMessage.
2034
2035	Selector Sel = PP.getSelectorTable().getNullarySelector(ID: Member);
2036	ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel);
2037
2038	// May be found in property's qualified list.
2039	if (!Getter)
2040	Getter = LookupMethodInQualifiedType(Sel, OPT, Instance: true);
2041
2042	// If this reference is in an @implementation, check for 'private' methods.
2043	if (!Getter)
2044	Getter = IFace->lookupPrivateMethod(Sel);
2045
2046	if (Getter) {
2047	// Check if we can reference this property.
2048	if (DiagnoseUseOfDecl(Getter, MemberLoc))
2049	return ExprError();
2050	}
2051	// If we found a getter then this may be a valid dot-reference, we
2052	// will look for the matching setter, in case it is needed.
2053	Selector SetterSel =
2054	SelectorTable::constructSetterSelector(Idents&: PP.getIdentifierTable(),
2055	SelTable&: PP.getSelectorTable(), Name: Member);
2056	ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(Sel: SetterSel);
2057
2058	// May be found in property's qualified list.
2059	if (!Setter)
2060	Setter = LookupMethodInQualifiedType(Sel: SetterSel, OPT, Instance: true);
2061
2062	if (!Setter) {
2063	// If this reference is in an @implementation, also check for 'private'
2064	// methods.
2065	Setter = IFace->lookupPrivateMethod(Sel: SetterSel);
2066	}
2067
2068	if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc))
2069	return ExprError();
2070
2071	// Special warning if member name used in a property-dot for a setter accessor
2072	// does not use a property with same name; e.g. obj.X = ... for a property with
2073	// name 'x'.
2074	if (Setter && Setter->isImplicit() && Setter->isPropertyAccessor() &&
2075	!IFace->FindPropertyDeclaration(
2076	Member, ObjCPropertyQueryKind::OBJC_PR_query_instance)) {
2077	if (const ObjCPropertyDecl *PDecl = Setter->findPropertyDecl()) {
2078	// Do not warn if user is using property-dot syntax to make call to
2079	// user named setter.
2080	if (!(PDecl->getPropertyAttributes() &
2081	ObjCPropertyAttribute::kind_setter))
2082	Diag(MemberLoc,
2083	diag::warn_property_access_suggest)
2084	<< MemberName << QualType(OPT, 0) << PDecl->getName()
2085	<< FixItHint::CreateReplacement(MemberLoc, PDecl->getName());
2086	}
2087	}
2088
2089	if (Getter || Setter) {
2090	if (Super)
2091	return new (Context)
2092	ObjCPropertyRefExpr(Getter, Setter, Context.PseudoObjectTy, VK_LValue,
2093	OK_ObjCProperty, MemberLoc, SuperLoc, SuperType);
2094	else
2095	return new (Context)
2096	ObjCPropertyRefExpr(Getter, Setter, Context.PseudoObjectTy, VK_LValue,
2097	OK_ObjCProperty, MemberLoc, BaseExpr);
2098
2099	}
2100
2101	// Attempt to correct for typos in property names.
2102	DeclFilterCCC<ObjCPropertyDecl> CCC{};
2103	if (TypoCorrection Corrected = CorrectTypo(
2104	DeclarationNameInfo(MemberName, MemberLoc), LookupOrdinaryName,
2105	nullptr, nullptr, CCC, CTK_ErrorRecovery, IFace, false, OPT)) {
2106	DeclarationName TypoResult = Corrected.getCorrection();
2107	if (TypoResult.isIdentifier() &&
2108	TypoResult.getAsIdentifierInfo() == Member) {
2109	// There is no need to try the correction if it is the same.
2110	NamedDecl *ChosenDecl =
2111	Corrected.isKeyword() ? nullptr : Corrected.getFoundDecl();
2112	if (ChosenDecl && isa<ObjCPropertyDecl>(Val: ChosenDecl))
2113	if (cast<ObjCPropertyDecl>(Val: ChosenDecl)->isClassProperty()) {
2114	// This is a class property, we should not use the instance to
2115	// access it.
2116	Diag(MemberLoc, diag::err_class_property_found) << MemberName
2117	<< OPT->getInterfaceDecl()->getName()
2118	<< FixItHint::CreateReplacement(BaseExpr->getSourceRange(),
2119	OPT->getInterfaceDecl()->getName());
2120	return ExprError();
2121	}
2122	} else {
2123	diagnoseTypo(Corrected, PDiag(diag::err_property_not_found_suggest)
2124	<< MemberName << QualType(OPT, 0));
2125	return HandleExprPropertyRefExpr(OPT, BaseExpr, OpLoc,
2126	MemberName: TypoResult, MemberLoc,
2127	SuperLoc, SuperType, Super);
2128	}
2129	}
2130	ObjCInterfaceDecl *ClassDeclared;
2131	if (ObjCIvarDecl *Ivar =
2132	IFace->lookupInstanceVariable(IVarName: Member, ClassDeclared)) {
2133	QualType T = Ivar->getType();
2134	if (const ObjCObjectPointerType * OBJPT =
2135	T->getAsObjCInterfacePointerType()) {
2136	if (RequireCompleteType(MemberLoc, OBJPT->getPointeeType(),
2137	diag::err_property_not_as_forward_class,
2138	MemberName, BaseExpr))
2139	return ExprError();
2140	}
2141	Diag(MemberLoc,
2142	diag::err_ivar_access_using_property_syntax_suggest)
2143	<< MemberName << QualType(OPT, 0) << Ivar->getDeclName()
2144	<< FixItHint::CreateReplacement(OpLoc, "->");
2145	return ExprError();
2146	}
2147
2148	Diag(MemberLoc, diag::err_property_not_found)
2149	<< MemberName << QualType(OPT, 0);
2150	if (Setter)
2151	Diag(Setter->getLocation(), diag::note_getter_unavailable)
2152	<< MemberName << BaseExpr->getSourceRange();
2153	return ExprError();
2154	}
2155
2156	ExprResult Sema::ActOnClassPropertyRefExpr(const IdentifierInfo &receiverName,
2157	const IdentifierInfo &propertyName,
2158	SourceLocation receiverNameLoc,
2159	SourceLocation propertyNameLoc) {
2160
2161	const IdentifierInfo *receiverNamePtr = &receiverName;
2162	ObjCInterfaceDecl *IFace = getObjCInterfaceDecl(Id&: receiverNamePtr,
2163	IdLoc: receiverNameLoc);
2164
2165	QualType SuperType;
2166	if (!IFace) {
2167	// If the "receiver" is 'super' in a method, handle it as an expression-like
2168	// property reference.
2169	if (receiverNamePtr->isStr(Str: "super")) {
2170	if (ObjCMethodDecl *CurMethod = tryCaptureObjCSelf(Loc: receiverNameLoc)) {
2171	if (auto classDecl = CurMethod->getClassInterface()) {
2172	SuperType = QualType(classDecl->getSuperClassType(), 0);
2173	if (CurMethod->isInstanceMethod()) {
2174	if (SuperType.isNull()) {
2175	// The current class does not have a superclass.
2176	Diag(receiverNameLoc, diag::err_root_class_cannot_use_super)
2177	<< CurMethod->getClassInterface()->getIdentifier();
2178	return ExprError();
2179	}
2180	QualType T = Context.getObjCObjectPointerType(OIT: SuperType);
2181
2182	return HandleExprPropertyRefExpr(OPT: T->castAs<ObjCObjectPointerType>(),
2183	/*BaseExpr*/nullptr,
2184	OpLoc: SourceLocation()/*OpLoc*/,
2185	MemberName: &propertyName,
2186	MemberLoc: propertyNameLoc,
2187	SuperLoc: receiverNameLoc, SuperType: T, Super: true);
2188	}
2189
2190	// Otherwise, if this is a class method, try dispatching to our
2191	// superclass.
2192	IFace = CurMethod->getClassInterface()->getSuperClass();
2193	}
2194	}
2195	}
2196
2197	if (!IFace) {
2198	Diag(receiverNameLoc, diag::err_expected_either) << tok::identifier
2199	<< tok::l_paren;
2200	return ExprError();
2201	}
2202	}
2203
2204	Selector GetterSel;
2205	Selector SetterSel;
2206	if (auto PD = IFace->FindPropertyDeclaration(
2207	&propertyName, ObjCPropertyQueryKind::OBJC_PR_query_class)) {
2208	GetterSel = PD->getGetterName();
2209	SetterSel = PD->getSetterName();
2210	} else {
2211	GetterSel = PP.getSelectorTable().getNullarySelector(ID: &propertyName);
2212	SetterSel = SelectorTable::constructSetterSelector(
2213	Idents&: PP.getIdentifierTable(), SelTable&: PP.getSelectorTable(), Name: &propertyName);
2214	}
2215
2216	// Search for a declared property first.
2217	ObjCMethodDecl *Getter = IFace->lookupClassMethod(Sel: GetterSel);
2218
2219	// If this reference is in an @implementation, check for 'private' methods.
2220	if (!Getter)
2221	Getter = IFace->lookupPrivateClassMethod(Sel: GetterSel);
2222
2223	if (Getter) {
2224	// FIXME: refactor/share with ActOnMemberReference().
2225	// Check if we can reference this property.
2226	if (DiagnoseUseOfDecl(Getter, propertyNameLoc))
2227	return ExprError();
2228	}
2229
2230	// Look for the matching setter, in case it is needed.
2231	ObjCMethodDecl *Setter = IFace->lookupClassMethod(Sel: SetterSel);
2232	if (!Setter) {
2233	// If this reference is in an @implementation, also check for 'private'
2234	// methods.
2235	Setter = IFace->lookupPrivateClassMethod(Sel: SetterSel);
2236	}
2237	// Look through local category implementations associated with the class.
2238	if (!Setter)
2239	Setter = IFace->getCategoryClassMethod(Sel: SetterSel);
2240
2241	if (Setter && DiagnoseUseOfDecl(Setter, propertyNameLoc))
2242	return ExprError();
2243
2244	if (Getter || Setter) {
2245	if (!SuperType.isNull())
2246	return new (Context)
2247	ObjCPropertyRefExpr(Getter, Setter, Context.PseudoObjectTy, VK_LValue,
2248	OK_ObjCProperty, propertyNameLoc, receiverNameLoc,
2249	SuperType);
2250
2251	return new (Context) ObjCPropertyRefExpr(
2252	Getter, Setter, Context.PseudoObjectTy, VK_LValue, OK_ObjCProperty,
2253	propertyNameLoc, receiverNameLoc, IFace);
2254	}
2255	return ExprError(Diag(propertyNameLoc, diag::err_property_not_found)
2256	<< &propertyName << Context.getObjCInterfaceType(IFace));
2257	}
2258
2259	namespace {
2260
2261	class ObjCInterfaceOrSuperCCC final : public CorrectionCandidateCallback {
2262	public:
2263	ObjCInterfaceOrSuperCCC(ObjCMethodDecl *Method) {
2264	// Determine whether "super" is acceptable in the current context.
2265	if (Method && Method->getClassInterface())
2266	WantObjCSuper = Method->getClassInterface()->getSuperClass();
2267	}
2268
2269	bool ValidateCandidate(const TypoCorrection &candidate) override {
2270	return candidate.getCorrectionDeclAs<ObjCInterfaceDecl>() ||
2271	candidate.isKeyword(Str: "super");
2272	}
2273
2274	std::unique_ptr<CorrectionCandidateCallback> clone() override {
2275	return std::make_unique<ObjCInterfaceOrSuperCCC>(args&: *this);
2276	}
2277	};
2278
2279	} // end anonymous namespace
2280
2281	Sema::ObjCMessageKind Sema::getObjCMessageKind(Scope *S,
2282	IdentifierInfo *Name,
2283	SourceLocation NameLoc,
2284	bool IsSuper,
2285	bool HasTrailingDot,
2286	ParsedType &ReceiverType) {
2287	ReceiverType = nullptr;
2288
2289	// If the identifier is "super" and there is no trailing dot, we're
2290	// messaging super. If the identifier is "super" and there is a
2291	// trailing dot, it's an instance message.
2292	if (IsSuper && S->isInObjcMethodScope())
2293	return HasTrailingDot? ObjCInstanceMessage : ObjCSuperMessage;
2294
2295	LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName);
2296	LookupName(R&: Result, S);
2297
2298	switch (Result.getResultKind()) {
2299	case LookupResult::NotFound:
2300	// Normal name lookup didn't find anything. If we're in an
2301	// Objective-C method, look for ivars. If we find one, we're done!
2302	// FIXME: This is a hack. Ivar lookup should be part of normal
2303	// lookup.
2304	if (ObjCMethodDecl *Method = getCurMethodDecl()) {
2305	if (!Method->getClassInterface()) {
2306	// Fall back: let the parser try to parse it as an instance message.
2307	return ObjCInstanceMessage;
2308	}
2309
2310	ObjCInterfaceDecl *ClassDeclared;
2311	if (Method->getClassInterface()->lookupInstanceVariable(IVarName: Name,
2312	ClassDeclared))
2313	return ObjCInstanceMessage;
2314	}
2315
2316	// Break out; we'll perform typo correction below.
2317	break;
2318
2319	case LookupResult::NotFoundInCurrentInstantiation:
2320	case LookupResult::FoundOverloaded:
2321	case LookupResult::FoundUnresolvedValue:
2322	case LookupResult::Ambiguous:
2323	Result.suppressDiagnostics();
2324	return ObjCInstanceMessage;
2325
2326	case LookupResult::Found: {
2327	// If the identifier is a class or not, and there is a trailing dot,
2328	// it's an instance message.
2329	if (HasTrailingDot)
2330	return ObjCInstanceMessage;
2331	// We found something. If it's a type, then we have a class
2332	// message. Otherwise, it's an instance message.
2333	NamedDecl *ND = Result.getFoundDecl();
2334	QualType T;
2335	if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(Val: ND))
2336	T = Context.getObjCInterfaceType(Decl: Class);
2337	else if (TypeDecl *Type = dyn_cast<TypeDecl>(Val: ND)) {
2338	T = Context.getTypeDeclType(Decl: Type);
2339	DiagnoseUseOfDecl(Type, NameLoc);
2340	}
2341	else
2342	return ObjCInstanceMessage;
2343
2344	// We have a class message, and T is the type we're
2345	// messaging. Build source-location information for it.
2346	TypeSourceInfo *TSInfo = Context.getTrivialTypeSourceInfo(T, Loc: NameLoc);
2347	ReceiverType = CreateParsedType(T, TInfo: TSInfo);
2348	return ObjCClassMessage;
2349	}
2350	}
2351
2352	ObjCInterfaceOrSuperCCC CCC(getCurMethodDecl());
2353	if (TypoCorrection Corrected = CorrectTypo(
2354	Typo: Result.getLookupNameInfo(), LookupKind: Result.getLookupKind(), S, SS: nullptr, CCC,
2355	Mode: CTK_ErrorRecovery, MemberContext: nullptr, EnteringContext: false, OPT: nullptr, RecordFailure: false)) {
2356	if (Corrected.isKeyword()) {
2357	// If we've found the keyword "super" (the only keyword that would be
2358	// returned by CorrectTypo), this is a send to super.
2359	diagnoseTypo(Corrected,
2360	PDiag(diag::err_unknown_receiver_suggest) << Name);
2361	return ObjCSuperMessage;
2362	} else if (ObjCInterfaceDecl *Class =
2363	Corrected.getCorrectionDeclAs<ObjCInterfaceDecl>()) {
2364	// If we found a declaration, correct when it refers to an Objective-C
2365	// class.
2366	diagnoseTypo(Corrected,
2367	PDiag(diag::err_unknown_receiver_suggest) << Name);
2368	QualType T = Context.getObjCInterfaceType(Decl: Class);
2369	TypeSourceInfo *TSInfo = Context.getTrivialTypeSourceInfo(T, Loc: NameLoc);
2370	ReceiverType = CreateParsedType(T, TInfo: TSInfo);
2371	return ObjCClassMessage;
2372	}
2373	}
2374
2375	// Fall back: let the parser try to parse it as an instance message.
2376	return ObjCInstanceMessage;
2377	}
2378
2379	ExprResult Sema::ActOnSuperMessage(Scope *S,
2380	SourceLocation SuperLoc,
2381	Selector Sel,
2382	SourceLocation LBracLoc,
2383	ArrayRef<SourceLocation> SelectorLocs,
2384	SourceLocation RBracLoc,
2385	MultiExprArg Args) {
2386	// Determine whether we are inside a method or not.
2387	ObjCMethodDecl *Method = tryCaptureObjCSelf(Loc: SuperLoc);
2388	if (!Method) {
2389	Diag(SuperLoc, diag::err_invalid_receiver_to_message_super);
2390	return ExprError();
2391	}
2392
2393	ObjCInterfaceDecl *Class = Method->getClassInterface();
2394	if (!Class) {
2395	Diag(SuperLoc, diag::err_no_super_class_message)
2396	<< Method->getDeclName();
2397	return ExprError();
2398	}
2399
2400	QualType SuperTy(Class->getSuperClassType(), 0);
2401	if (SuperTy.isNull()) {
2402	// The current class does not have a superclass.
2403	Diag(SuperLoc, diag::err_root_class_cannot_use_super)
2404	<< Class->getIdentifier();
2405	return ExprError();
2406	}
2407
2408	// We are in a method whose class has a superclass, so 'super'
2409	// is acting as a keyword.
2410	if (Method->getSelector() == Sel)
2411	getCurFunction()->ObjCShouldCallSuper = false;
2412
2413	if (Method->isInstanceMethod()) {
2414	// Since we are in an instance method, this is an instance
2415	// message to the superclass instance.
2416	SuperTy = Context.getObjCObjectPointerType(OIT: SuperTy);
2417	return BuildInstanceMessage(Receiver: nullptr, ReceiverType: SuperTy, SuperLoc,
2418	Sel, /*Method=*/nullptr,
2419	LBracLoc, SelectorLocs, RBracLoc, Args);
2420	}
2421
2422	// Since we are in a class method, this is a class message to
2423	// the superclass.
2424	return BuildClassMessage(/*ReceiverTypeInfo=*/nullptr,
2425	ReceiverType: SuperTy,
2426	SuperLoc, Sel, /*Method=*/nullptr,
2427	LBracLoc, SelectorLocs, RBracLoc, Args);
2428	}
2429
2430	ExprResult Sema::BuildClassMessageImplicit(QualType ReceiverType,
2431	bool isSuperReceiver,
2432	SourceLocation Loc,
2433	Selector Sel,
2434	ObjCMethodDecl *Method,
2435	MultiExprArg Args) {
2436	TypeSourceInfo *receiverTypeInfo = nullptr;
2437	if (!ReceiverType.isNull())
2438	receiverTypeInfo = Context.getTrivialTypeSourceInfo(T: ReceiverType);
2439
2440	assert(((isSuperReceiver && Loc.isValid()) || receiverTypeInfo) &&
2441	"Either the super receiver location needs to be valid or the receiver "
2442	"needs valid type source information");
2443	return BuildClassMessage(ReceiverTypeInfo: receiverTypeInfo, ReceiverType,
2444	/*SuperLoc=*/isSuperReceiver ? Loc : SourceLocation(),
2445	Sel, Method, LBracLoc: Loc, SelectorLocs: Loc, RBracLoc: Loc, Args,
2446	/*isImplicit=*/true);
2447	}
2448
2449	static void applyCocoaAPICheck(Sema &S, const ObjCMessageExpr *Msg,
2450	unsigned DiagID,
2451	bool (*refactor)(const ObjCMessageExpr *,
2452	const NSAPI &, edit::Commit &)) {
2453	SourceLocation MsgLoc = Msg->getExprLoc();
2454	if (S.Diags.isIgnored(DiagID, Loc: MsgLoc))
2455	return;
2456
2457	SourceManager &SM = S.SourceMgr;
2458	edit::Commit ECommit(SM, S.LangOpts);
2459	if (refactor(Msg,*S.NSAPIObj, ECommit)) {
2460	auto Builder = S.Diag(MsgLoc, DiagID)
2461	<< Msg->getSelector() << Msg->getSourceRange();
2462	// FIXME: Don't emit diagnostic at all if fixits are non-commitable.
2463	if (!ECommit.isCommitable())
2464	return;
2465	for (edit::Commit::edit_iterator
2466	I = ECommit.edit_begin(), E = ECommit.edit_end(); I != E; ++I) {
2467	const edit::Commit::Edit &Edit = *I;
2468	switch (Edit.Kind) {
2469	case edit::Commit::Act_Insert:
2470	Builder.AddFixItHint(FixItHint::CreateInsertion(InsertionLoc: Edit.OrigLoc,
2471	Code: Edit.Text,
2472	BeforePreviousInsertions: Edit.BeforePrev));
2473	break;
2474	case edit::Commit::Act_InsertFromRange:
2475	Builder.AddFixItHint(
2476	FixItHint::CreateInsertionFromRange(InsertionLoc: Edit.OrigLoc,
2477	FromRange: Edit.getInsertFromRange(SM),
2478	BeforePreviousInsertions: Edit.BeforePrev));
2479	break;
2480	case edit::Commit::Act_Remove:
2481	Builder.AddFixItHint(FixItHint::CreateRemoval(RemoveRange: Edit.getFileRange(SM)));
2482	break;
2483	}
2484	}
2485	}
2486	}
2487
2488	static void checkCocoaAPI(Sema &S, const ObjCMessageExpr *Msg) {
2489	applyCocoaAPICheck(S, Msg, diag::warn_objc_redundant_literal_use,
2490	edit::rewriteObjCRedundantCallWithLiteral);
2491	}
2492
2493	static void checkFoundationAPI(Sema &S, SourceLocation Loc,
2494	const ObjCMethodDecl *Method,
2495	ArrayRef<Expr *> Args, QualType ReceiverType,
2496	bool IsClassObjectCall) {
2497	// Check if this is a performSelector method that uses a selector that returns
2498	// a record or a vector type.
2499	if (Method->getSelector().getMethodFamily() != OMF_performSelector ||
2500	Args.empty())
2501	return;
2502	const auto *SE = dyn_cast<ObjCSelectorExpr>(Val: Args[0]->IgnoreParens());
2503	if (!SE)
2504	return;
2505	ObjCMethodDecl *ImpliedMethod;
2506	if (!IsClassObjectCall) {
2507	const auto *OPT = ReceiverType->getAs<ObjCObjectPointerType>();
2508	if (!OPT || !OPT->getInterfaceDecl())
2509	return;
2510	ImpliedMethod =
2511	OPT->getInterfaceDecl()->lookupInstanceMethod(Sel: SE->getSelector());
2512	if (!ImpliedMethod)
2513	ImpliedMethod =
2514	OPT->getInterfaceDecl()->lookupPrivateMethod(Sel: SE->getSelector());
2515	} else {
2516	const auto *IT = ReceiverType->getAs<ObjCInterfaceType>();
2517	if (!IT)
2518	return;
2519	ImpliedMethod = IT->getDecl()->lookupClassMethod(Sel: SE->getSelector());
2520	if (!ImpliedMethod)
2521	ImpliedMethod =
2522	IT->getDecl()->lookupPrivateClassMethod(Sel: SE->getSelector());
2523	}
2524	if (!ImpliedMethod)
2525	return;
2526	QualType Ret = ImpliedMethod->getReturnType();
2527	if (Ret->isRecordType() || Ret->isVectorType() || Ret->isExtVectorType()) {
2528	S.Diag(Loc, diag::warn_objc_unsafe_perform_selector)
2529	<< Method->getSelector()
2530	<< (!Ret->isRecordType()
2531	? /*Vector*/ 2
2532	: Ret->isUnionType() ? /*Union*/ 1 : /*Struct*/ 0);
2533	S.Diag(ImpliedMethod->getBeginLoc(),
2534	diag::note_objc_unsafe_perform_selector_method_declared_here)
2535	<< ImpliedMethod->getSelector() << Ret;
2536	}
2537	}
2538
2539	/// Diagnose use of %s directive in an NSString which is being passed
2540	/// as formatting string to formatting method.
2541	static void
2542	DiagnoseCStringFormatDirectiveInObjCAPI(Sema &S,
2543	ObjCMethodDecl *Method,
2544	Selector Sel,
2545	Expr **Args, unsigned NumArgs) {
2546	unsigned Idx = 0;
2547	bool Format = false;
2548	ObjCStringFormatFamily SFFamily = Sel.getStringFormatFamily();
2549	if (SFFamily == ObjCStringFormatFamily::SFF_NSString) {
2550	Idx = 0;
2551	Format = true;
2552	}
2553	else if (Method) {
2554	for (const auto *I : Method->specific_attrs<FormatAttr>()) {
2555	if (S.GetFormatNSStringIdx(I, Idx)) {
2556	Format = true;
2557	break;
2558	}
2559	}
2560	}
2561	if (!Format || NumArgs <= Idx)
2562	return;
2563
2564	Expr *FormatExpr = Args[Idx];
2565	if (ObjCStringLiteral *OSL =
2566	dyn_cast<ObjCStringLiteral>(Val: FormatExpr->IgnoreParenImpCasts())) {
2567	StringLiteral *FormatString = OSL->getString();
2568	if (S.FormatStringHasSArg(FExpr: FormatString)) {
2569	S.Diag(FormatExpr->getExprLoc(), diag::warn_objc_cdirective_format_string)
2570	<< "%s" << 0 << 0;
2571	if (Method)
2572	S.Diag(Method->getLocation(), diag::note_method_declared_at)
2573	<< Method->getDeclName();
2574	}
2575	}
2576	}
2577
2578	/// Build an Objective-C class message expression.
2579	///
2580	/// This routine takes care of both normal class messages and
2581	/// class messages to the superclass.
2582	///
2583	/// \param ReceiverTypeInfo Type source information that describes the
2584	/// receiver of this message. This may be NULL, in which case we are
2585	/// sending to the superclass and \p SuperLoc must be a valid source
2586	/// location.
2587
2588	/// \param ReceiverType The type of the object receiving the
2589	/// message. When \p ReceiverTypeInfo is non-NULL, this is the same
2590	/// type as that refers to. For a superclass send, this is the type of
2591	/// the superclass.
2592	///
2593	/// \param SuperLoc The location of the "super" keyword in a
2594	/// superclass message.
2595	///
2596	/// \param Sel The selector to which the message is being sent.
2597	///
2598	/// \param Method The method that this class message is invoking, if
2599	/// already known.
2600	///
2601	/// \param LBracLoc The location of the opening square bracket ']'.
2602	///
2603	/// \param RBracLoc The location of the closing square bracket ']'.
2604	///
2605	/// \param ArgsIn The message arguments.
2606	ExprResult Sema::BuildClassMessage(TypeSourceInfo *ReceiverTypeInfo,
2607	QualType ReceiverType,
2608	SourceLocation SuperLoc,
2609	Selector Sel,
2610	ObjCMethodDecl *Method,
2611	SourceLocation LBracLoc,
2612	ArrayRef<SourceLocation> SelectorLocs,
2613	SourceLocation RBracLoc,
2614	MultiExprArg ArgsIn,
2615	bool isImplicit) {
2616	SourceLocation Loc = SuperLoc.isValid()? SuperLoc
2617	: ReceiverTypeInfo->getTypeLoc().getSourceRange().getBegin();
2618	if (LBracLoc.isInvalid()) {
2619	Diag(Loc, diag::err_missing_open_square_message_send)
2620	<< FixItHint::CreateInsertion(Loc, "[");
2621	LBracLoc = Loc;
2622	}
2623	ArrayRef<SourceLocation> SelectorSlotLocs;
2624	if (!SelectorLocs.empty() && SelectorLocs.front().isValid())
2625	SelectorSlotLocs = SelectorLocs;
2626	else
2627	SelectorSlotLocs = Loc;
2628	SourceLocation SelLoc = SelectorSlotLocs.front();
2629
2630	if (ReceiverType->isDependentType()) {
2631	// If the receiver type is dependent, we can't type-check anything
2632	// at this point. Build a dependent expression.
2633	unsigned NumArgs = ArgsIn.size();
2634	Expr **Args = ArgsIn.data();
2635	assert(SuperLoc.isInvalid() && "Message to super with dependent type");
2636	return ObjCMessageExpr::Create(Context, T: ReceiverType, VK: VK_PRValue, LBracLoc,
2637	Receiver: ReceiverTypeInfo, Sel, SelLocs: SelectorLocs,
2638	/*Method=*/nullptr, Args: ArrayRef(Args, NumArgs),
2639	RBracLoc, isImplicit);
2640	}
2641
2642	// Find the class to which we are sending this message.
2643	ObjCInterfaceDecl *Class = nullptr;
2644	const ObjCObjectType *ClassType = ReceiverType->getAs<ObjCObjectType>();
2645	if (!ClassType || !(Class = ClassType->getInterface())) {
2646	Diag(Loc, diag::err_invalid_receiver_class_message)
2647	<< ReceiverType;
2648	return ExprError();
2649	}
2650	assert(Class && "We don't know which class we're messaging?");
2651	// objc++ diagnoses during typename annotation.
2652	if (!getLangOpts().CPlusPlus)
2653	(void)DiagnoseUseOfDecl(Class, SelectorSlotLocs);
2654	// Find the method we are messaging.
2655	if (!Method) {
2656	SourceRange TypeRange
2657	= SuperLoc.isValid()? SourceRange(SuperLoc)
2658	: ReceiverTypeInfo->getTypeLoc().getSourceRange();
2659	if (RequireCompleteType(Loc, Context.getObjCInterfaceType(Class),
2660	(getLangOpts().ObjCAutoRefCount
2661	? diag::err_arc_receiver_forward_class
2662	: diag::warn_receiver_forward_class),
2663	TypeRange)) {
2664	// A forward class used in messaging is treated as a 'Class'
2665	Method = LookupFactoryMethodInGlobalPool(Sel,
2666	R: SourceRange(LBracLoc, RBracLoc));
2667	if (Method && !getLangOpts().ObjCAutoRefCount)
2668	Diag(Method->getLocation(), diag::note_method_sent_forward_class)
2669	<< Method->getDeclName();
2670	}
2671	if (!Method)
2672	Method = Class->lookupClassMethod(Sel);
2673
2674	// If we have an implementation in scope, check "private" methods.
2675	if (!Method)
2676	Method = Class->lookupPrivateClassMethod(Sel);
2677
2678	if (Method && DiagnoseUseOfDecl(Method, SelectorSlotLocs,
2679	nullptr, false, false, Class))
2680	return ExprError();
2681	}
2682
2683	// Check the argument types and determine the result type.
2684	QualType ReturnType;
2685	ExprValueKind VK = VK_PRValue;
2686
2687	unsigned NumArgs = ArgsIn.size();
2688	Expr **Args = ArgsIn.data();
2689	if (CheckMessageArgumentTypes(/*Receiver=*/nullptr, ReceiverType,
2690	Args: MultiExprArg(Args, NumArgs), Sel, SelectorLocs,
2691	Method, isClassMessage: true, isSuperMessage: SuperLoc.isValid(), lbrac: LBracLoc,
2692	rbrac: RBracLoc, RecRange: SourceRange(), ReturnType, VK))
2693	return ExprError();
2694
2695	if (Method && !Method->getReturnType()->isVoidType() &&
2696	RequireCompleteType(LBracLoc, Method->getReturnType(),
2697	diag::err_illegal_message_expr_incomplete_type))
2698	return ExprError();
2699
2700	if (Method && Method->isDirectMethod() && SuperLoc.isValid()) {
2701	Diag(SuperLoc, diag::err_messaging_super_with_direct_method)
2702	<< FixItHint::CreateReplacement(
2703	SuperLoc, getLangOpts().ObjCAutoRefCount
2704	? "self"
2705	: Method->getClassInterface()->getName());
2706	Diag(Method->getLocation(), diag::note_direct_method_declared_at)
2707	<< Method->getDeclName();
2708	}
2709
2710	// Warn about explicit call of +initialize on its own class. But not on 'super'.
2711	if (Method && Method->getMethodFamily() == OMF_initialize) {
2712	if (!SuperLoc.isValid()) {
2713	const ObjCInterfaceDecl *ID =
2714	dyn_cast<ObjCInterfaceDecl>(Method->getDeclContext());
2715	if (ID == Class) {
2716	Diag(Loc, diag::warn_direct_initialize_call);
2717	Diag(Method->getLocation(), diag::note_method_declared_at)
2718	<< Method->getDeclName();
2719	}
2720	}
2721	else if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) {
2722	// [super initialize] is allowed only within an +initialize implementation
2723	if (CurMeth->getMethodFamily() != OMF_initialize) {
2724	Diag(Loc, diag::warn_direct_super_initialize_call);
2725	Diag(Method->getLocation(), diag::note_method_declared_at)
2726	<< Method->getDeclName();
2727	Diag(CurMeth->getLocation(), diag::note_method_declared_at)
2728	<< CurMeth->getDeclName();
2729	}
2730	}
2731	}
2732
2733	DiagnoseCStringFormatDirectiveInObjCAPI(S&: *this, Method, Sel, Args, NumArgs);
2734
2735	// Construct the appropriate ObjCMessageExpr.
2736	ObjCMessageExpr *Result;
2737	if (SuperLoc.isValid())
2738	Result = ObjCMessageExpr::Create(
2739	Context, T: ReturnType, VK, LBracLoc, SuperLoc, /*IsInstanceSuper=*/false,
2740	SuperType: ReceiverType, Sel, SelLocs: SelectorLocs, Method, Args: ArrayRef(Args, NumArgs),
2741	RBracLoc, isImplicit);
2742	else {
2743	Result = ObjCMessageExpr::Create(
2744	Context, T: ReturnType, VK, LBracLoc, Receiver: ReceiverTypeInfo, Sel, SelLocs: SelectorLocs,
2745	Method, Args: ArrayRef(Args, NumArgs), RBracLoc, isImplicit);
2746	if (!isImplicit)
2747	checkCocoaAPI(S&: *this, Msg: Result);
2748	}
2749	if (Method)
2750	checkFoundationAPI(S&: *this, Loc: SelLoc, Method, Args: ArrayRef(Args, NumArgs),
2751	ReceiverType, /*IsClassObjectCall=*/true);
2752	return MaybeBindToTemporary(Result);
2753	}
2754
2755	// ActOnClassMessage - used for both unary and keyword messages.
2756	// ArgExprs is optional - if it is present, the number of expressions
2757	// is obtained from Sel.getNumArgs().
2758	ExprResult Sema::ActOnClassMessage(Scope *S,
2759	ParsedType Receiver,
2760	Selector Sel,
2761	SourceLocation LBracLoc,
2762	ArrayRef<SourceLocation> SelectorLocs,
2763	SourceLocation RBracLoc,
2764	MultiExprArg Args) {
2765	TypeSourceInfo *ReceiverTypeInfo;
2766	QualType ReceiverType = GetTypeFromParser(Ty: Receiver, TInfo: &ReceiverTypeInfo);
2767	if (ReceiverType.isNull())
2768	return ExprError();
2769
2770	if (!ReceiverTypeInfo)
2771	ReceiverTypeInfo = Context.getTrivialTypeSourceInfo(T: ReceiverType, Loc: LBracLoc);
2772
2773	return BuildClassMessage(ReceiverTypeInfo, ReceiverType,
2774	/*SuperLoc=*/SourceLocation(), Sel,
2775	/*Method=*/nullptr, LBracLoc, SelectorLocs, RBracLoc,
2776	ArgsIn: Args);
2777	}
2778
2779	ExprResult Sema::BuildInstanceMessageImplicit(Expr *Receiver,
2780	QualType ReceiverType,
2781	SourceLocation Loc,
2782	Selector Sel,
2783	ObjCMethodDecl *Method,
2784	MultiExprArg Args) {
2785	return BuildInstanceMessage(Receiver, ReceiverType,
2786	/*SuperLoc=*/!Receiver ? Loc : SourceLocation(),
2787	Sel, Method, LBracLoc: Loc, SelectorLocs: Loc, RBracLoc: Loc, Args,
2788	/*isImplicit=*/true);
2789	}
2790
2791	static bool isMethodDeclaredInRootProtocol(Sema &S, const ObjCMethodDecl *M) {
2792	if (!S.NSAPIObj)
2793	return false;
2794	const auto *Protocol = dyn_cast<ObjCProtocolDecl>(M->getDeclContext());
2795	if (!Protocol)
2796	return false;
2797	const IdentifierInfo *II = S.NSAPIObj->getNSClassId(K: NSAPI::ClassId_NSObject);
2798	if (const auto *RootClass = dyn_cast_or_null<ObjCInterfaceDecl>(
2799	S.LookupSingleName(S.TUScope, II, Protocol->getBeginLoc(),
2800	Sema::LookupOrdinaryName))) {
2801	for (const ObjCProtocolDecl *P : RootClass->all_referenced_protocols()) {
2802	if (P->getCanonicalDecl() == Protocol->getCanonicalDecl())
2803	return true;
2804	}
2805	}
2806	return false;
2807	}
2808
2809	/// Build an Objective-C instance message expression.
2810	///
2811	/// This routine takes care of both normal instance messages and
2812	/// instance messages to the superclass instance.
2813	///
2814	/// \param Receiver The expression that computes the object that will
2815	/// receive this message. This may be empty, in which case we are
2816	/// sending to the superclass instance and \p SuperLoc must be a valid
2817	/// source location.
2818	///
2819	/// \param ReceiverType The (static) type of the object receiving the
2820	/// message. When a \p Receiver expression is provided, this is the
2821	/// same type as that expression. For a superclass instance send, this
2822	/// is a pointer to the type of the superclass.
2823	///
2824	/// \param SuperLoc The location of the "super" keyword in a
2825	/// superclass instance message.
2826	///
2827	/// \param Sel The selector to which the message is being sent.
2828	///
2829	/// \param Method The method that this instance message is invoking, if
2830	/// already known.
2831	///
2832	/// \param LBracLoc The location of the opening square bracket ']'.
2833	///
2834	/// \param RBracLoc The location of the closing square bracket ']'.
2835	///
2836	/// \param ArgsIn The message arguments.
2837	ExprResult Sema::BuildInstanceMessage(Expr *Receiver,
2838	QualType ReceiverType,
2839	SourceLocation SuperLoc,
2840	Selector Sel,
2841	ObjCMethodDecl *Method,
2842	SourceLocation LBracLoc,
2843	ArrayRef<SourceLocation> SelectorLocs,
2844	SourceLocation RBracLoc,
2845	MultiExprArg ArgsIn,
2846	bool isImplicit) {
2847	assert((Receiver || SuperLoc.isValid()) && "If the Receiver is null, the "
2848	"SuperLoc must be valid so we can "
2849	"use it instead.");
2850
2851	// The location of the receiver.
2852	SourceLocation Loc = SuperLoc.isValid() ? SuperLoc : Receiver->getBeginLoc();
2853	SourceRange RecRange =
2854	SuperLoc.isValid()? SuperLoc : Receiver->getSourceRange();
2855	ArrayRef<SourceLocation> SelectorSlotLocs;
2856	if (!SelectorLocs.empty() && SelectorLocs.front().isValid())
2857	SelectorSlotLocs = SelectorLocs;
2858	else
2859	SelectorSlotLocs = Loc;
2860	SourceLocation SelLoc = SelectorSlotLocs.front();
2861
2862	if (LBracLoc.isInvalid()) {
2863	Diag(Loc, diag::err_missing_open_square_message_send)
2864	<< FixItHint::CreateInsertion(Loc, "[");
2865	LBracLoc = Loc;
2866	}
2867
2868	// If we have a receiver expression, perform appropriate promotions
2869	// and determine receiver type.
2870	if (Receiver) {
2871	if (Receiver->hasPlaceholderType()) {
2872	ExprResult Result;
2873	if (Receiver->getType() == Context.UnknownAnyTy)
2874	Result = forceUnknownAnyToType(E: Receiver, ToType: Context.getObjCIdType());
2875	else
2876	Result = CheckPlaceholderExpr(E: Receiver);
2877	if (Result.isInvalid()) return ExprError();
2878	Receiver = Result.get();
2879	}
2880
2881	if (Receiver->isTypeDependent()) {
2882	// If the receiver is type-dependent, we can't type-check anything
2883	// at this point. Build a dependent expression.
2884	unsigned NumArgs = ArgsIn.size();
2885	Expr **Args = ArgsIn.data();
2886	assert(SuperLoc.isInvalid() && "Message to super with dependent type");
2887	return ObjCMessageExpr::Create(
2888	Context, Context.DependentTy, VK_PRValue, LBracLoc, Receiver, Sel,
2889	SelectorLocs, /*Method=*/nullptr, ArrayRef(Args, NumArgs), RBracLoc,
2890	isImplicit);
2891	}
2892
2893	// If necessary, apply function/array conversion to the receiver.
2894	// C99 6.7.5.3p[7,8].
2895	ExprResult Result = DefaultFunctionArrayLvalueConversion(E: Receiver);
2896	if (Result.isInvalid())
2897	return ExprError();
2898	Receiver = Result.get();
2899	ReceiverType = Receiver->getType();
2900
2901	// If the receiver is an ObjC pointer, a block pointer, or an
2902	// __attribute__((NSObject)) pointer, we don't need to do any
2903	// special conversion in order to look up a receiver.
2904	if (ReceiverType->isObjCRetainableType()) {
2905	// do nothing
2906	} else if (!getLangOpts().ObjCAutoRefCount &&
2907	!Context.getObjCIdType().isNull() &&
2908	(ReceiverType->isPointerType() ||
2909	ReceiverType->isIntegerType())) {
2910	// Implicitly convert integers and pointers to 'id' but emit a warning.
2911	// But not in ARC.
2912	Diag(Loc, diag::warn_bad_receiver_type) << ReceiverType << RecRange;
2913	if (ReceiverType->isPointerType()) {
2914	Receiver = ImpCastExprToType(E: Receiver, Type: Context.getObjCIdType(),
2915	CK: CK_CPointerToObjCPointerCast).get();
2916	} else {
2917	// TODO: specialized warning on null receivers?
2918	bool IsNull = Receiver->isNullPointerConstant(Ctx&: Context,
2919	NPC: Expr::NPC_ValueDependentIsNull);
2920	CastKind Kind = IsNull ? CK_NullToPointer : CK_IntegralToPointer;
2921	Receiver = ImpCastExprToType(E: Receiver, Type: Context.getObjCIdType(),
2922	CK: Kind).get();
2923	}
2924	ReceiverType = Receiver->getType();
2925	} else if (getLangOpts().CPlusPlus) {
2926	// The receiver must be a complete type.
2927	if (RequireCompleteType(Loc, Receiver->getType(),
2928	diag::err_incomplete_receiver_type))
2929	return ExprError();
2930
2931	ExprResult result = PerformContextuallyConvertToObjCPointer(From: Receiver);
2932	if (result.isUsable()) {
2933	Receiver = result.get();
2934	ReceiverType = Receiver->getType();
2935	}
2936	}
2937	}
2938
2939	// There's a somewhat weird interaction here where we assume that we
2940	// won't actually have a method unless we also don't need to do some
2941	// of the more detailed type-checking on the receiver.
2942
2943	if (!Method) {
2944	// Handle messages to id and __kindof types (where we use the
2945	// global method pool).
2946	const ObjCObjectType *typeBound = nullptr;
2947	bool receiverIsIdLike = ReceiverType->isObjCIdOrObjectKindOfType(Context,
2948	typeBound);
2949	if (receiverIsIdLike || ReceiverType->isBlockPointerType() ||
2950	(Receiver && Context.isObjCNSObjectType(Ty: Receiver->getType()))) {
2951	SmallVector<ObjCMethodDecl*, 4> Methods;
2952	// If we have a type bound, further filter the methods.
2953	CollectMultipleMethodsInGlobalPool(Sel, Methods, InstanceFirst: true/*InstanceFirst*/,
2954	CheckTheOther: true/*CheckTheOther*/, TypeBound: typeBound);
2955	if (!Methods.empty()) {
2956	// We choose the first method as the initial candidate, then try to
2957	// select a better one.
2958	Method = Methods[0];
2959
2960	if (ObjCMethodDecl *BestMethod =
2961	SelectBestMethod(Sel, Args: ArgsIn, IsInstance: Method->isInstanceMethod(), Methods))
2962	Method = BestMethod;
2963
2964	if (!AreMultipleMethodsInGlobalPool(Sel, BestMethod: Method,
2965	R: SourceRange(LBracLoc, RBracLoc),
2966	receiverIdOrClass: receiverIsIdLike, Methods))
2967	DiagnoseUseOfDecl(Method, SelectorSlotLocs);
2968	}
2969	} else if (ReceiverType->isObjCClassOrClassKindOfType() ||
2970	ReceiverType->isObjCQualifiedClassType()) {
2971	// Handle messages to Class.
2972	// We allow sending a message to a qualified Class ("Class<foo>"), which
2973	// is ok as long as one of the protocols implements the selector (if not,
2974	// warn).
2975	if (!ReceiverType->isObjCClassOrClassKindOfType()) {
2976	const ObjCObjectPointerType *QClassTy
2977	= ReceiverType->getAsObjCQualifiedClassType();
2978	// Search protocols for class methods.
2979	Method = LookupMethodInQualifiedType(Sel, OPT: QClassTy, Instance: false);
2980	if (!Method) {
2981	Method = LookupMethodInQualifiedType(Sel, OPT: QClassTy, Instance: true);
2982	// warn if instance method found for a Class message.
2983	if (Method && !isMethodDeclaredInRootProtocol(S&: *this, M: Method)) {
2984	Diag(SelLoc, diag::warn_instance_method_on_class_found)
2985	<< Method->getSelector() << Sel;
2986	Diag(Method->getLocation(), diag::note_method_declared_at)
2987	<< Method->getDeclName();
2988	}
2989	}
2990	} else {
2991	if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) {
2992	if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface()) {
2993	// As a guess, try looking for the method in the current interface.
2994	// This very well may not produce the "right" method.
2995
2996	// First check the public methods in the class interface.
2997	Method = ClassDecl->lookupClassMethod(Sel);
2998
2999	if (!Method)
3000	Method = ClassDecl->lookupPrivateClassMethod(Sel);
3001
3002	if (Method && DiagnoseUseOfDecl(Method, SelectorSlotLocs))
3003	return ExprError();
3004	}
3005	}
3006	if (!Method) {
3007	// If not messaging 'self', look for any factory method named 'Sel'.
3008	if (!Receiver || !isSelfExpr(RExpr: Receiver)) {
3009	// If no class (factory) method was found, check if an _instance_
3010	// method of the same name exists in the root class only.
3011	SmallVector<ObjCMethodDecl*, 4> Methods;
3012	CollectMultipleMethodsInGlobalPool(Sel, Methods,
3013	InstanceFirst: false/*InstanceFirst*/,
3014	CheckTheOther: true/*CheckTheOther*/);
3015	if (!Methods.empty()) {
3016	// We choose the first method as the initial candidate, then try
3017	// to select a better one.
3018	Method = Methods[0];
3019
3020	// If we find an instance method, emit warning.
3021	if (Method->isInstanceMethod()) {
3022	if (const ObjCInterfaceDecl *ID =
3023	dyn_cast<ObjCInterfaceDecl>(Method->getDeclContext())) {
3024	if (ID->getSuperClass())
3025	Diag(SelLoc, diag::warn_root_inst_method_not_found)
3026	<< Sel << SourceRange(LBracLoc, RBracLoc);
3027	}
3028	}
3029
3030	if (ObjCMethodDecl *BestMethod =
3031	SelectBestMethod(Sel, Args: ArgsIn, IsInstance: Method->isInstanceMethod(),
3032	Methods))
3033	Method = BestMethod;
3034	}
3035	}
3036	}
3037	}
3038	} else {
3039	ObjCInterfaceDecl *ClassDecl = nullptr;
3040
3041	// We allow sending a message to a qualified ID ("id<foo>"), which is ok as
3042	// long as one of the protocols implements the selector (if not, warn).
3043	// And as long as message is not deprecated/unavailable (warn if it is).
3044	if (const ObjCObjectPointerType *QIdTy
3045	= ReceiverType->getAsObjCQualifiedIdType()) {
3046	// Search protocols for instance methods.
3047	Method = LookupMethodInQualifiedType(Sel, OPT: QIdTy, Instance: true);
3048	if (!Method)
3049	Method = LookupMethodInQualifiedType(Sel, OPT: QIdTy, Instance: false);
3050	if (Method && DiagnoseUseOfDecl(Method, SelectorSlotLocs))
3051	return ExprError();
3052	} else if (const ObjCObjectPointerType *OCIType
3053	= ReceiverType->getAsObjCInterfacePointerType()) {
3054	// We allow sending a message to a pointer to an interface (an object).
3055	ClassDecl = OCIType->getInterfaceDecl();
3056
3057	// Try to complete the type. Under ARC, this is a hard error from which
3058	// we don't try to recover.
3059	// FIXME: In the non-ARC case, this will still be a hard error if the
3060	// definition is found in a module that's not visible.
3061	const ObjCInterfaceDecl *forwardClass = nullptr;
3062	if (RequireCompleteType(Loc, OCIType->getPointeeType(),
3063	getLangOpts().ObjCAutoRefCount
3064	? diag::err_arc_receiver_forward_instance
3065	: diag::warn_receiver_forward_instance,
3066	RecRange)) {
3067	if (getLangOpts().ObjCAutoRefCount)
3068	return ExprError();
3069
3070	forwardClass = OCIType->getInterfaceDecl();
3071	Diag(Receiver ? Receiver->getBeginLoc() : SuperLoc,
3072	diag::note_receiver_is_id);
3073	Method = nullptr;
3074	} else {
3075	Method = ClassDecl->lookupInstanceMethod(Sel);
3076	}
3077
3078	if (!Method)
3079	// Search protocol qualifiers.
3080	Method = LookupMethodInQualifiedType(Sel, OPT: OCIType, Instance: true);
3081
3082	if (!Method) {
3083	// If we have implementations in scope, check "private" methods.
3084	Method = ClassDecl->lookupPrivateMethod(Sel);
3085
3086	if (!Method && getLangOpts().ObjCAutoRefCount) {
3087	Diag(SelLoc, diag::err_arc_may_not_respond)
3088	<< OCIType->getPointeeType() << Sel << RecRange
3089	<< SourceRange(SelectorLocs.front(), SelectorLocs.back());
3090	return ExprError();
3091	}
3092
3093	if (!Method && (!Receiver || !isSelfExpr(RExpr: Receiver))) {
3094	// If we still haven't found a method, look in the global pool. This
3095	// behavior isn't very desirable, however we need it for GCC
3096	// compatibility. FIXME: should we deviate??
3097	if (OCIType->qual_empty()) {
3098	SmallVector<ObjCMethodDecl*, 4> Methods;
3099	CollectMultipleMethodsInGlobalPool(Sel, Methods,
3100	InstanceFirst: true/*InstanceFirst*/,
3101	CheckTheOther: false/*CheckTheOther*/);
3102	if (!Methods.empty()) {
3103	// We choose the first method as the initial candidate, then try
3104	// to select a better one.
3105	Method = Methods[0];
3106
3107	if (ObjCMethodDecl *BestMethod =
3108	SelectBestMethod(Sel, Args: ArgsIn, IsInstance: Method->isInstanceMethod(),
3109	Methods))
3110	Method = BestMethod;
3111
3112	AreMultipleMethodsInGlobalPool(Sel, BestMethod: Method,
3113	R: SourceRange(LBracLoc, RBracLoc),
3114	receiverIdOrClass: true/*receiverIdOrClass*/,
3115	Methods);
3116	}
3117	if (Method && !forwardClass)
3118	Diag(SelLoc, diag::warn_maynot_respond)
3119	<< OCIType->getInterfaceDecl()->getIdentifier()
3120	<< Sel << RecRange;
3121	}
3122	}
3123	}
3124	if (Method && DiagnoseUseOfDecl(Method, SelectorSlotLocs, forwardClass))
3125	return ExprError();
3126	} else {
3127	// Reject other random receiver types (e.g. structs).
3128	Diag(Loc, diag::err_bad_receiver_type) << ReceiverType << RecRange;
3129	return ExprError();
3130	}
3131	}
3132	}
3133
3134	FunctionScopeInfo *DIFunctionScopeInfo =
3135	(Method && Method->getMethodFamily() == OMF_init)
3136	? getEnclosingFunction() : nullptr;
3137
3138	if (Method && Method->isDirectMethod()) {
3139	if (ReceiverType->isObjCIdType() && !isImplicit) {
3140	Diag(Receiver->getExprLoc(),
3141	diag::err_messaging_unqualified_id_with_direct_method);
3142	Diag(Method->getLocation(), diag::note_direct_method_declared_at)
3143	<< Method->getDeclName();
3144	}
3145
3146	// Under ARC, self can't be assigned, and doing a direct call to `self`
3147	// when it's a Class is hence safe. For other cases, we can't trust `self`
3148	// is what we think it is, so we reject it.
3149	if (ReceiverType->isObjCClassType() && !isImplicit &&
3150	!(Receiver->isObjCSelfExpr() && getLangOpts().ObjCAutoRefCount)) {
3151	{
3152	auto Builder = Diag(Receiver->getExprLoc(),
3153	diag::err_messaging_class_with_direct_method);
3154	if (Receiver->isObjCSelfExpr()) {
3155	Builder.AddFixItHint(FixItHint::CreateReplacement(
3156	RecRange, Method->getClassInterface()->getName()));
3157	}
3158	}
3159	Diag(Method->getLocation(), diag::note_direct_method_declared_at)
3160	<< Method->getDeclName();
3161	}
3162
3163	if (SuperLoc.isValid()) {
3164	{
3165	auto Builder =
3166	Diag(SuperLoc, diag::err_messaging_super_with_direct_method);
3167	if (ReceiverType->isObjCClassType()) {
3168	Builder.AddFixItHint(FixItHint::CreateReplacement(
3169	SuperLoc, Method->getClassInterface()->getName()));
3170	} else {
3171	Builder.AddFixItHint(FixItHint::CreateReplacement(RemoveRange: SuperLoc, Code: "self"));
3172	}
3173	}
3174	Diag(Method->getLocation(), diag::note_direct_method_declared_at)
3175	<< Method->getDeclName();
3176	}
3177	} else if (ReceiverType->isObjCIdType() && !isImplicit) {
3178	Diag(Receiver->getExprLoc(), diag::warn_messaging_unqualified_id);
3179	}
3180
3181	if (DIFunctionScopeInfo &&
3182	DIFunctionScopeInfo->ObjCIsDesignatedInit &&
3183	(SuperLoc.isValid() || isSelfExpr(RExpr: Receiver))) {
3184	bool isDesignatedInitChain = false;
3185	if (SuperLoc.isValid()) {
3186	if (const ObjCObjectPointerType *
3187	OCIType = ReceiverType->getAsObjCInterfacePointerType()) {
3188	if (const ObjCInterfaceDecl *ID = OCIType->getInterfaceDecl()) {
3189	// Either we know this is a designated initializer or we
3190	// conservatively assume it because we don't know for sure.
3191	if (!ID->declaresOrInheritsDesignatedInitializers() ||
3192	ID->isDesignatedInitializer(Sel)) {
3193	isDesignatedInitChain = true;
3194	DIFunctionScopeInfo->ObjCWarnForNoDesignatedInitChain = false;
3195	}
3196	}
3197	}
3198	}
3199	if (!isDesignatedInitChain) {
3200	const ObjCMethodDecl *InitMethod = nullptr;
3201	bool isDesignated =
3202	getCurMethodDecl()->isDesignatedInitializerForTheInterface(InitMethod: &InitMethod);
3203	assert(isDesignated && InitMethod);
3204	(void)isDesignated;
3205	Diag(SelLoc, SuperLoc.isValid() ?
3206	diag::warn_objc_designated_init_non_designated_init_call :
3207	diag::warn_objc_designated_init_non_super_designated_init_call);
3208	Diag(InitMethod->getLocation(),
3209	diag::note_objc_designated_init_marked_here);
3210	}
3211	}
3212
3213	if (DIFunctionScopeInfo &&
3214	DIFunctionScopeInfo->ObjCIsSecondaryInit &&
3215	(SuperLoc.isValid() || isSelfExpr(RExpr: Receiver))) {
3216	if (SuperLoc.isValid()) {
3217	Diag(SelLoc, diag::warn_objc_secondary_init_super_init_call);
3218	} else {
3219	DIFunctionScopeInfo->ObjCWarnForNoInitDelegation = false;
3220	}
3221	}
3222
3223	// Check the message arguments.
3224	unsigned NumArgs = ArgsIn.size();
3225	Expr **Args = ArgsIn.data();
3226	QualType ReturnType;
3227	ExprValueKind VK = VK_PRValue;
3228	bool ClassMessage = (ReceiverType->isObjCClassType() ||
3229	ReceiverType->isObjCQualifiedClassType());
3230	if (CheckMessageArgumentTypes(Receiver, ReceiverType,
3231	Args: MultiExprArg(Args, NumArgs), Sel, SelectorLocs,
3232	Method, isClassMessage: ClassMessage, isSuperMessage: SuperLoc.isValid(),
3233	lbrac: LBracLoc, rbrac: RBracLoc, RecRange, ReturnType, VK))
3234	return ExprError();
3235
3236	if (Method && !Method->getReturnType()->isVoidType() &&
3237	RequireCompleteType(LBracLoc, Method->getReturnType(),
3238	diag::err_illegal_message_expr_incomplete_type))
3239	return ExprError();
3240
3241	// In ARC, forbid the user from sending messages to
3242	// retain/release/autorelease/dealloc/retainCount explicitly.
3243	if (getLangOpts().ObjCAutoRefCount) {
3244	ObjCMethodFamily family =
3245	(Method ? Method->getMethodFamily() : Sel.getMethodFamily());
3246	switch (family) {
3247	case OMF_init:
3248	if (Method)
3249	checkInitMethod(method: Method, receiverTypeIfCall: ReceiverType);
3250	break;
3251
3252	case OMF_None:
3253	case OMF_alloc:
3254	case OMF_copy:
3255	case OMF_finalize:
3256	case OMF_mutableCopy:
3257	case OMF_new:
3258	case OMF_self:
3259	case OMF_initialize:
3260	break;
3261
3262	case OMF_dealloc:
3263	case OMF_retain:
3264	case OMF_release:
3265	case OMF_autorelease:
3266	case OMF_retainCount:
3267	Diag(SelLoc, diag::err_arc_illegal_explicit_message)
3268	<< Sel << RecRange;
3269	break;
3270
3271	case OMF_performSelector:
3272	if (Method && NumArgs >= 1) {
3273	if (const auto *SelExp =
3274	dyn_cast<ObjCSelectorExpr>(Val: Args[0]->IgnoreParens())) {
3275	Selector ArgSel = SelExp->getSelector();
3276	ObjCMethodDecl *SelMethod =
3277	LookupInstanceMethodInGlobalPool(Sel: ArgSel,
3278	R: SelExp->getSourceRange());
3279	if (!SelMethod)
3280	SelMethod =
3281	LookupFactoryMethodInGlobalPool(Sel: ArgSel,
3282	R: SelExp->getSourceRange());
3283	if (SelMethod) {
3284	ObjCMethodFamily SelFamily = SelMethod->getMethodFamily();
3285	switch (SelFamily) {
3286	case OMF_alloc:
3287	case OMF_copy:
3288	case OMF_mutableCopy:
3289	case OMF_new:
3290	case OMF_init:
3291	// Issue error, unless ns_returns_not_retained.
3292	if (!SelMethod->hasAttr<NSReturnsNotRetainedAttr>()) {
3293	// selector names a +1 method
3294	Diag(SelLoc,
3295	diag::err_arc_perform_selector_retains);
3296	Diag(SelMethod->getLocation(), diag::note_method_declared_at)
3297	<< SelMethod->getDeclName();
3298	}
3299	break;
3300	default:
3301	// +0 call. OK. unless ns_returns_retained.
3302	if (SelMethod->hasAttr<NSReturnsRetainedAttr>()) {
3303	// selector names a +1 method
3304	Diag(SelLoc,
3305	diag::err_arc_perform_selector_retains);
3306	Diag(SelMethod->getLocation(), diag::note_method_declared_at)
3307	<< SelMethod->getDeclName();
3308	}
3309	break;
3310	}
3311	}
3312	} else {
3313	// error (may leak).
3314	Diag(SelLoc, diag::warn_arc_perform_selector_leaks);
3315	Diag(Args[0]->getExprLoc(), diag::note_used_here);
3316	}
3317	}
3318	break;
3319	}
3320	}
3321
3322	DiagnoseCStringFormatDirectiveInObjCAPI(S&: *this, Method, Sel, Args, NumArgs);
3323
3324	// Construct the appropriate ObjCMessageExpr instance.
3325	ObjCMessageExpr *Result;
3326	if (SuperLoc.isValid())
3327	Result = ObjCMessageExpr::Create(
3328	Context, T: ReturnType, VK, LBracLoc, SuperLoc, /*IsInstanceSuper=*/true,
3329	SuperType: ReceiverType, Sel, SelLocs: SelectorLocs, Method, Args: ArrayRef(Args, NumArgs),
3330	RBracLoc, isImplicit);
3331	else {
3332	Result = ObjCMessageExpr::Create(
3333	Context, T: ReturnType, VK, LBracLoc, Receiver, Sel, SeLocs: SelectorLocs, Method,
3334	Args: ArrayRef(Args, NumArgs), RBracLoc, isImplicit);
3335	if (!isImplicit)
3336	checkCocoaAPI(S&: *this, Msg: Result);
3337	}
3338	if (Method) {
3339	bool IsClassObjectCall = ClassMessage;
3340	// 'self' message receivers in class methods should be treated as message
3341	// sends to the class object in order for the semantic checks to be
3342	// performed correctly. Messages to 'super' already count as class messages,
3343	// so they don't need to be handled here.
3344	if (Receiver && isSelfExpr(RExpr: Receiver)) {
3345	if (const auto *OPT = ReceiverType->getAs<ObjCObjectPointerType>()) {
3346	if (OPT->getObjectType()->isObjCClass()) {
3347	if (const auto *CurMeth = getCurMethodDecl()) {
3348	IsClassObjectCall = true;
3349	ReceiverType =
3350	Context.getObjCInterfaceType(Decl: CurMeth->getClassInterface());
3351	}
3352	}
3353	}
3354	}
3355	checkFoundationAPI(S&: *this, Loc: SelLoc, Method, Args: ArrayRef(Args, NumArgs),
3356	ReceiverType, IsClassObjectCall);
3357	}
3358
3359	if (getLangOpts().ObjCAutoRefCount) {
3360	// In ARC, annotate delegate init calls.
3361	if (Result->getMethodFamily() == OMF_init &&
3362	(SuperLoc.isValid() || isSelfExpr(RExpr: Receiver))) {
3363	// Only consider init calls *directly* in init implementations,
3364	// not within blocks.
3365	ObjCMethodDecl *method = dyn_cast<ObjCMethodDecl>(Val: CurContext);
3366	if (method && method->getMethodFamily() == OMF_init) {
3367	// The implicit assignment to self means we also don't want to
3368	// consume the result.
3369	Result->setDelegateInitCall(true);
3370	return Result;
3371	}
3372	}
3373
3374	// In ARC, check for message sends which are likely to introduce
3375	// retain cycles.
3376	checkRetainCycles(msg: Result);
3377	}
3378
3379	if (getLangOpts().ObjCWeak) {
3380	if (!isImplicit && Method) {
3381	if (const ObjCPropertyDecl *Prop = Method->findPropertyDecl()) {
3382	bool IsWeak =
3383	Prop->getPropertyAttributes() & ObjCPropertyAttribute::kind_weak;
3384	if (!IsWeak && Sel.isUnarySelector())
3385	IsWeak = ReturnType.getObjCLifetime() & Qualifiers::OCL_Weak;
3386	if (IsWeak && !isUnevaluatedContext() &&
3387	!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, LBracLoc))
3388	getCurFunction()->recordUseOfWeak(Msg: Result, Prop);
3389	}
3390	}
3391	}
3392
3393	CheckObjCCircularContainer(Message: Result);
3394
3395	return MaybeBindToTemporary(Result);
3396	}
3397
3398	static void RemoveSelectorFromWarningCache(Sema &S, Expr* Arg) {
3399	if (ObjCSelectorExpr *OSE =
3400	dyn_cast<ObjCSelectorExpr>(Val: Arg->IgnoreParenCasts())) {
3401	Selector Sel = OSE->getSelector();
3402	SourceLocation Loc = OSE->getAtLoc();
3403	auto Pos = S.ReferencedSelectors.find(Key: Sel);
3404	if (Pos != S.ReferencedSelectors.end() && Pos->second == Loc)
3405	S.ReferencedSelectors.erase(Iterator: Pos);
3406	}
3407	}
3408
3409	// ActOnInstanceMessage - used for both unary and keyword messages.
3410	// ArgExprs is optional - if it is present, the number of expressions
3411	// is obtained from Sel.getNumArgs().
3412	ExprResult Sema::ActOnInstanceMessage(Scope *S,
3413	Expr *Receiver,
3414	Selector Sel,
3415	SourceLocation LBracLoc,
3416	ArrayRef<SourceLocation> SelectorLocs,
3417	SourceLocation RBracLoc,
3418	MultiExprArg Args) {
3419	if (!Receiver)
3420	return ExprError();
3421
3422	// A ParenListExpr can show up while doing error recovery with invalid code.
3423	if (isa<ParenListExpr>(Val: Receiver)) {
3424	ExprResult Result = MaybeConvertParenListExprToParenExpr(S, ME: Receiver);
3425	if (Result.isInvalid()) return ExprError();
3426	Receiver = Result.get();
3427	}
3428
3429	if (RespondsToSelectorSel.isNull()) {
3430	IdentifierInfo *SelectorId = &Context.Idents.get(Name: "respondsToSelector");
3431	RespondsToSelectorSel = Context.Selectors.getUnarySelector(SelectorId);
3432	}
3433	if (Sel == RespondsToSelectorSel)
3434	RemoveSelectorFromWarningCache(S&: *this, Arg: Args[0]);
3435
3436	return BuildInstanceMessage(Receiver, ReceiverType: Receiver->getType(),
3437	/*SuperLoc=*/SourceLocation(), Sel,
3438	/*Method=*/nullptr, LBracLoc, SelectorLocs,
3439	RBracLoc, ArgsIn: Args);
3440	}
3441
3442	enum ARCConversionTypeClass {
3443	/// int, void, struct A
3444	ACTC_none,
3445
3446	/// id, void (^)()
3447	ACTC_retainable,
3448
3449	/// id*, id***, void (^*)(),
3450	ACTC_indirectRetainable,
3451
3452	/// void* might be a normal C type, or it might a CF type.
3453	ACTC_voidPtr,
3454
3455	/// struct A*
3456	ACTC_coreFoundation
3457	};
3458
3459	static bool isAnyRetainable(ARCConversionTypeClass ACTC) {
3460	return (ACTC == ACTC_retainable ||
3461	ACTC == ACTC_coreFoundation ||
3462	ACTC == ACTC_voidPtr);
3463	}
3464
3465	static bool isAnyCLike(ARCConversionTypeClass ACTC) {
3466	return ACTC == ACTC_none ||
3467	ACTC == ACTC_voidPtr ||
3468	ACTC == ACTC_coreFoundation;
3469	}
3470
3471	static ARCConversionTypeClass classifyTypeForARCConversion(QualType type) {
3472	bool isIndirect = false;
3473
3474	// Ignore an outermost reference type.
3475	if (const ReferenceType *ref = type->getAs<ReferenceType>()) {
3476	type = ref->getPointeeType();
3477	isIndirect = true;
3478	}
3479
3480	// Drill through pointers and arrays recursively.
3481	while (true) {
3482	if (const PointerType *ptr = type->getAs<PointerType>()) {
3483	type = ptr->getPointeeType();
3484
3485	// The first level of pointer may be the innermost pointer on a CF type.
3486	if (!isIndirect) {
3487	if (type->isVoidType()) return ACTC_voidPtr;
3488	if (type->isRecordType()) return ACTC_coreFoundation;
3489	}
3490	} else if (const ArrayType *array = type->getAsArrayTypeUnsafe()) {
3491	type = QualType(array->getElementType()->getBaseElementTypeUnsafe(), 0);
3492	} else {
3493	break;
3494	}
3495	isIndirect = true;
3496	}
3497
3498	if (isIndirect) {
3499	if (type->isObjCARCBridgableType())
3500	return ACTC_indirectRetainable;
3501	return ACTC_none;
3502	}
3503
3504	if (type->isObjCARCBridgableType())
3505	return ACTC_retainable;
3506
3507	return ACTC_none;
3508	}
3509
3510	namespace {
3511	/// A result from the cast checker.
3512	enum ACCResult {
3513	/// Cannot be casted.
3514	ACC_invalid,
3515
3516	/// Can be safely retained or not retained.
3517	ACC_bottom,
3518
3519	/// Can be casted at +0.
3520	ACC_plusZero,
3521
3522	/// Can be casted at +1.
3523	ACC_plusOne
3524	};
3525	ACCResult merge(ACCResult left, ACCResult right) {
3526	if (left == right) return left;
3527	if (left == ACC_bottom) return right;
3528	if (right == ACC_bottom) return left;
3529	return ACC_invalid;
3530	}
3531
3532	/// A checker which white-lists certain expressions whose conversion
3533	/// to or from retainable type would otherwise be forbidden in ARC.
3534	class ARCCastChecker : public StmtVisitor<ARCCastChecker, ACCResult> {
3535	typedef StmtVisitor<ARCCastChecker, ACCResult> super;
3536
3537	ASTContext &Context;
3538	ARCConversionTypeClass SourceClass;
3539	ARCConversionTypeClass TargetClass;
3540	bool Diagnose;
3541
3542	static bool isCFType(QualType type) {
3543	// Someday this can use ns_bridged. For now, it has to do this.
3544	return type->isCARCBridgableType();
3545	}
3546
3547	public:
3548	ARCCastChecker(ASTContext &Context, ARCConversionTypeClass source,
3549	ARCConversionTypeClass target, bool diagnose)
3550	: Context(Context), SourceClass(source), TargetClass(target),
3551	Diagnose(diagnose) {}
3552
3553	using super::Visit;
3554	ACCResult Visit(Expr *e) {
3555	return super::Visit(e->IgnoreParens());
3556	}
3557
3558	ACCResult VisitStmt(Stmt *s) {
3559	return ACC_invalid;
3560	}
3561
3562	/// Null pointer constants can be casted however you please.
3563	ACCResult VisitExpr(Expr *e) {
3564	if (e->isNullPointerConstant(Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNotNull))
3565	return ACC_bottom;
3566	return ACC_invalid;
3567	}
3568
3569	/// Objective-C string literals can be safely casted.
3570	ACCResult VisitObjCStringLiteral(ObjCStringLiteral *e) {
3571	// If we're casting to any retainable type, go ahead. Global
3572	// strings are immune to retains, so this is bottom.
3573	if (isAnyRetainable(ACTC: TargetClass)) return ACC_bottom;
3574
3575	return ACC_invalid;
3576	}
3577
3578	/// Look through certain implicit and explicit casts.
3579	ACCResult VisitCastExpr(CastExpr *e) {
3580	switch (e->getCastKind()) {
3581	case CK_NullToPointer:
3582	return ACC_bottom;
3583
3584	case CK_NoOp:
3585	case CK_LValueToRValue:
3586	case CK_BitCast:
3587	case CK_CPointerToObjCPointerCast:
3588	case CK_BlockPointerToObjCPointerCast:
3589	case CK_AnyPointerToBlockPointerCast:
3590	return Visit(e: e->getSubExpr());
3591
3592	default:
3593	return ACC_invalid;
3594	}
3595	}
3596
3597	/// Look through unary extension.
3598	ACCResult VisitUnaryExtension(UnaryOperator *e) {
3599	return Visit(e: e->getSubExpr());
3600	}
3601
3602	/// Ignore the LHS of a comma operator.
3603	ACCResult VisitBinComma(BinaryOperator *e) {
3604	return Visit(e: e->getRHS());
3605	}
3606
3607	/// Conditional operators are okay if both sides are okay.
3608	ACCResult VisitConditionalOperator(ConditionalOperator *e) {
3609	ACCResult left = Visit(e: e->getTrueExpr());
3610	if (left == ACC_invalid) return ACC_invalid;
3611	return merge(left, right: Visit(e: e->getFalseExpr()));
3612	}
3613
3614	/// Look through pseudo-objects.
3615	ACCResult VisitPseudoObjectExpr(PseudoObjectExpr *e) {
3616	// If we're getting here, we should always have a result.
3617	return Visit(e: e->getResultExpr());
3618	}
3619
3620	/// Statement expressions are okay if their result expression is okay.
3621	ACCResult VisitStmtExpr(StmtExpr *e) {
3622	return Visit(e->getSubStmt()->body_back());
3623	}
3624
3625	/// Some declaration references are okay.
3626	ACCResult VisitDeclRefExpr(DeclRefExpr *e) {
3627	VarDecl *var = dyn_cast<VarDecl>(Val: e->getDecl());
3628	// References to global constants are okay.
3629	if (isAnyRetainable(ACTC: TargetClass) &&
3630	isAnyRetainable(ACTC: SourceClass) &&
3631	var &&
3632	!var->hasDefinition(Context) &&
3633	var->getType().isConstQualified()) {
3634
3635	// In system headers, they can also be assumed to be immune to retains.
3636	// These are things like 'kCFStringTransformToLatin'.
3637	if (Context.getSourceManager().isInSystemHeader(Loc: var->getLocation()))
3638	return ACC_bottom;
3639
3640	return ACC_plusZero;
3641	}
3642
3643	// Nothing else.
3644	return ACC_invalid;
3645	}
3646
3647	/// Some calls are okay.
3648	ACCResult VisitCallExpr(CallExpr *e) {
3649	if (FunctionDecl *fn = e->getDirectCallee())
3650	if (ACCResult result = checkCallToFunction(fn))
3651	return result;
3652
3653	return super::VisitCallExpr(e);
3654	}
3655
3656	ACCResult checkCallToFunction(FunctionDecl *fn) {
3657	// Require a CF*Ref return type.
3658	if (!isCFType(type: fn->getReturnType()))
3659	return ACC_invalid;
3660
3661	if (!isAnyRetainable(ACTC: TargetClass))
3662	return ACC_invalid;
3663
3664	// Honor an explicit 'not retained' attribute.
3665	if (fn->hasAttr<CFReturnsNotRetainedAttr>())
3666	return ACC_plusZero;
3667
3668	// Honor an explicit 'retained' attribute, except that for
3669	// now we're not going to permit implicit handling of +1 results,
3670	// because it's a bit frightening.
3671	if (fn->hasAttr<CFReturnsRetainedAttr>())
3672	return Diagnose ? ACC_plusOne
3673	: ACC_invalid; // ACC_plusOne if we start accepting this
3674
3675	// Recognize this specific builtin function, which is used by CFSTR.
3676	unsigned builtinID = fn->getBuiltinID();
3677	if (builtinID == Builtin::BI__builtin___CFStringMakeConstantString)
3678	return ACC_bottom;
3679
3680	// Otherwise, don't do anything implicit with an unaudited function.
3681	if (!fn->hasAttr<CFAuditedTransferAttr>())
3682	return ACC_invalid;
3683
3684	// Otherwise, it's +0 unless it follows the create convention.
3685	if (ento::coreFoundation::followsCreateRule(FD: fn))
3686	return Diagnose ? ACC_plusOne
3687	: ACC_invalid; // ACC_plusOne if we start accepting this
3688
3689	return ACC_plusZero;
3690	}
3691
3692	ACCResult VisitObjCMessageExpr(ObjCMessageExpr *e) {
3693	return checkCallToMethod(method: e->getMethodDecl());
3694	}
3695
3696	ACCResult VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *e) {
3697	ObjCMethodDecl *method;
3698	if (e->isExplicitProperty())
3699	method = e->getExplicitProperty()->getGetterMethodDecl();
3700	else
3701	method = e->getImplicitPropertyGetter();
3702	return checkCallToMethod(method);
3703	}
3704
3705	ACCResult checkCallToMethod(ObjCMethodDecl *method) {
3706	if (!method) return ACC_invalid;
3707
3708	// Check for message sends to functions returning CF types. We
3709	// just obey the Cocoa conventions with these, even though the
3710	// return type is CF.
3711	if (!isAnyRetainable(ACTC: TargetClass) || !isCFType(type: method->getReturnType()))
3712	return ACC_invalid;
3713
3714	// If the method is explicitly marked not-retained, it's +0.
3715	if (method->hasAttr<CFReturnsNotRetainedAttr>())
3716	return ACC_plusZero;
3717
3718	// If the method is explicitly marked as returning retained, or its
3719	// selector follows a +1 Cocoa convention, treat it as +1.
3720	if (method->hasAttr<CFReturnsRetainedAttr>())
3721	return ACC_plusOne;
3722
3723	switch (method->getSelector().getMethodFamily()) {
3724	case OMF_alloc:
3725	case OMF_copy:
3726	case OMF_mutableCopy:
3727	case OMF_new:
3728	return ACC_plusOne;
3729
3730	default:
3731	// Otherwise, treat it as +0.
3732	return ACC_plusZero;
3733	}
3734	}
3735	};
3736	} // end anonymous namespace
3737
3738	bool Sema::isKnownName(StringRef name) {
3739	if (name.empty())
3740	return false;
3741	LookupResult R(*this, &Context.Idents.get(Name: name), SourceLocation(),
3742	Sema::LookupOrdinaryName);
3743	return LookupName(R, S: TUScope, AllowBuiltinCreation: false);
3744	}
3745
3746	template <typename DiagBuilderT>
3747	static void addFixitForObjCARCConversion(
3748	Sema &S, DiagBuilderT &DiagB, CheckedConversionKind CCK,
3749	SourceLocation afterLParen, QualType castType, Expr *castExpr,
3750	Expr *realCast, const char *bridgeKeyword, const char *CFBridgeName) {
3751	// We handle C-style and implicit casts here.
3752	switch (CCK) {
3753	case CheckedConversionKind::Implicit:
3754	case CheckedConversionKind::ForBuiltinOverloadedOp:
3755	case CheckedConversionKind::CStyleCast:
3756	case CheckedConversionKind::OtherCast:
3757	break;
3758	case CheckedConversionKind::FunctionalCast:
3759	return;
3760	}
3761
3762	if (CFBridgeName) {
3763	if (CCK == CheckedConversionKind::OtherCast) {
3764	if (const CXXNamedCastExpr *NCE = dyn_cast<CXXNamedCastExpr>(Val: realCast)) {
3765	SourceRange range(NCE->getOperatorLoc(),
3766	NCE->getAngleBrackets().getEnd());
3767	SmallString<32> BridgeCall;
3768
3769	SourceManager &SM = S.getSourceManager();
3770	char PrevChar = *SM.getCharacterData(SL: range.getBegin().getLocWithOffset(Offset: -1));
3771	if (Lexer::isAsciiIdentifierContinueChar(c: PrevChar, LangOpts: S.getLangOpts()))
3772	BridgeCall += ' ';
3773
3774	BridgeCall += CFBridgeName;
3775	DiagB.AddFixItHint(FixItHint::CreateReplacement(RemoveRange: range, Code: BridgeCall));
3776	}
3777	return;
3778	}
3779	Expr *castedE = castExpr;
3780	if (CStyleCastExpr *CCE = dyn_cast<CStyleCastExpr>(Val: castedE))
3781	castedE = CCE->getSubExpr();
3782	castedE = castedE->IgnoreImpCasts();
3783	SourceRange range = castedE->getSourceRange();
3784
3785	SmallString<32> BridgeCall;
3786
3787	SourceManager &SM = S.getSourceManager();
3788	char PrevChar = *SM.getCharacterData(SL: range.getBegin().getLocWithOffset(Offset: -1));
3789	if (Lexer::isAsciiIdentifierContinueChar(c: PrevChar, LangOpts: S.getLangOpts()))
3790	BridgeCall += ' ';
3791
3792	BridgeCall += CFBridgeName;
3793
3794	if (isa<ParenExpr>(Val: castedE)) {
3795	DiagB.AddFixItHint(FixItHint::CreateInsertion(InsertionLoc: range.getBegin(),
3796	Code: BridgeCall));
3797	} else {
3798	BridgeCall += '(';
3799	DiagB.AddFixItHint(FixItHint::CreateInsertion(InsertionLoc: range.getBegin(),
3800	Code: BridgeCall));
3801	DiagB.AddFixItHint(FixItHint::CreateInsertion(
3802	InsertionLoc: S.getLocForEndOfToken(Loc: range.getEnd()),
3803	Code: ")"));
3804	}
3805	return;
3806	}
3807
3808	if (CCK == CheckedConversionKind::CStyleCast) {
3809	DiagB.AddFixItHint(FixItHint::CreateInsertion(InsertionLoc: afterLParen, Code: bridgeKeyword));
3810	} else if (CCK == CheckedConversionKind::OtherCast) {
3811	if (const CXXNamedCastExpr *NCE = dyn_cast<CXXNamedCastExpr>(Val: realCast)) {
3812	std::string castCode = "(";
3813	castCode += bridgeKeyword;
3814	castCode += castType.getAsString();
3815	castCode += ")";
3816	SourceRange Range(NCE->getOperatorLoc(),
3817	NCE->getAngleBrackets().getEnd());
3818	DiagB.AddFixItHint(FixItHint::CreateReplacement(RemoveRange: Range, Code: castCode));
3819	}
3820	} else {
3821	std::string castCode = "(";
3822	castCode += bridgeKeyword;
3823	castCode += castType.getAsString();
3824	castCode += ")";
3825	Expr *castedE = castExpr->IgnoreImpCasts();
3826	SourceRange range = castedE->getSourceRange();
3827	if (isa<ParenExpr>(Val: castedE)) {
3828	DiagB.AddFixItHint(FixItHint::CreateInsertion(InsertionLoc: range.getBegin(),
3829	Code: castCode));
3830	} else {
3831	castCode += "(";
3832	DiagB.AddFixItHint(FixItHint::CreateInsertion(InsertionLoc: range.getBegin(),
3833	Code: castCode));
3834	DiagB.AddFixItHint(FixItHint::CreateInsertion(
3835	InsertionLoc: S.getLocForEndOfToken(Loc: range.getEnd()),
3836	Code: ")"));
3837	}
3838	}
3839	}
3840
3841	template <typename T>
3842	static inline T *getObjCBridgeAttr(const TypedefType *TD) {
3843	TypedefNameDecl *TDNDecl = TD->getDecl();
3844	QualType QT = TDNDecl->getUnderlyingType();
3845	if (QT->isPointerType()) {
3846	QT = QT->getPointeeType();
3847	if (const RecordType *RT = QT->getAs<RecordType>()) {
3848	for (auto *Redecl : RT->getDecl()->getMostRecentDecl()->redecls()) {
3849	if (auto *attr = Redecl->getAttr<T>())
3850	return attr;
3851	}
3852	}
3853	}
3854	return nullptr;
3855	}
3856
3857	static ObjCBridgeRelatedAttr *ObjCBridgeRelatedAttrFromType(QualType T,
3858	TypedefNameDecl *&TDNDecl) {
3859	while (const auto *TD = T->getAs<TypedefType>()) {
3860	TDNDecl = TD->getDecl();
3861	if (ObjCBridgeRelatedAttr *ObjCBAttr =
3862	getObjCBridgeAttr<ObjCBridgeRelatedAttr>(TD))
3863	return ObjCBAttr;
3864	T = TDNDecl->getUnderlyingType();
3865	}
3866	return nullptr;
3867	}
3868
3869	static void diagnoseObjCARCConversion(Sema &S, SourceRange castRange,
3870	QualType castType,
3871	ARCConversionTypeClass castACTC,
3872	Expr *castExpr, Expr *realCast,
3873	ARCConversionTypeClass exprACTC,
3874	CheckedConversionKind CCK) {
3875	SourceLocation loc =
3876	(castRange.isValid() ? castRange.getBegin() : castExpr->getExprLoc());
3877
3878	if (S.makeUnavailableInSystemHeader(loc,
3879	UnavailableAttr::IR_ARCForbiddenConversion))
3880	return;
3881
3882	QualType castExprType = castExpr->getType();
3883	// Defer emitting a diagnostic for bridge-related casts; that will be
3884	// handled by CheckObjCBridgeRelatedConversions.
3885	TypedefNameDecl *TDNDecl = nullptr;
3886	if ((castACTC == ACTC_coreFoundation && exprACTC == ACTC_retainable &&
3887	ObjCBridgeRelatedAttrFromType(castType, TDNDecl)) ||
3888	(exprACTC == ACTC_coreFoundation && castACTC == ACTC_retainable &&
3889	ObjCBridgeRelatedAttrFromType(castExprType, TDNDecl)))
3890	return;
3891
3892	unsigned srcKind = 0;
3893	switch (exprACTC) {
3894	case ACTC_none:
3895	case ACTC_coreFoundation:
3896	case ACTC_voidPtr:
3897	srcKind = (castExprType->isPointerType() ? 1 : 0);
3898	break;
3899	case ACTC_retainable:
3900	srcKind = (castExprType->isBlockPointerType() ? 2 : 3);
3901	break;
3902	case ACTC_indirectRetainable:
3903	srcKind = 4;
3904	break;
3905	}
3906
3907	// Check whether this could be fixed with a bridge cast.
3908	SourceLocation afterLParen = S.getLocForEndOfToken(Loc: castRange.getBegin());
3909	SourceLocation noteLoc = afterLParen.isValid() ? afterLParen : loc;
3910
3911	unsigned convKindForDiag = Sema::isCast(CCK) ? 0 : 1;
3912
3913	// Bridge from an ARC type to a CF type.
3914	if (castACTC == ACTC_retainable && isAnyRetainable(ACTC: exprACTC)) {
3915
3916	S.Diag(loc, diag::err_arc_cast_requires_bridge)
3917	<< convKindForDiag
3918	<< 2 // of C pointer type
3919	<< castExprType
3920	<< unsigned(castType->isBlockPointerType()) // to ObjC|block type
3921	<< castType
3922	<< castRange
3923	<< castExpr->getSourceRange();
3924	bool br = S.isKnownName(name: "CFBridgingRelease");
3925	ACCResult CreateRule =
3926	ARCCastChecker(S.Context, exprACTC, castACTC, true).Visit(e: castExpr);
3927	assert(CreateRule != ACC_bottom && "This cast should already be accepted.");
3928	if (CreateRule != ACC_plusOne)
3929	{
3930	auto DiagB = (CCK != CheckedConversionKind::OtherCast)
3931	? S.Diag(noteLoc, diag::note_arc_bridge)
3932	: S.Diag(noteLoc, diag::note_arc_cstyle_bridge);
3933
3934	addFixitForObjCARCConversion(S, DiagB, CCK, afterLParen,
3935	castType, castExpr, realCast, "__bridge ",
3936	nullptr);
3937	}
3938	if (CreateRule != ACC_plusZero)
3939	{
3940	auto DiagB = (CCK == CheckedConversionKind::OtherCast && !br)
3941	? S.Diag(noteLoc, diag::note_arc_cstyle_bridge_transfer)
3942	<< castExprType
3943	: S.Diag(br ? castExpr->getExprLoc() : noteLoc,
3944	diag::note_arc_bridge_transfer)
3945	<< castExprType << br;
3946
3947	addFixitForObjCARCConversion(S, DiagB, CCK, afterLParen,
3948	castType, castExpr, realCast, "__bridge_transfer ",
3949	br ? "CFBridgingRelease" : nullptr);
3950	}
3951
3952	return;
3953	}
3954
3955	// Bridge from a CF type to an ARC type.
3956	if (exprACTC == ACTC_retainable && isAnyRetainable(ACTC: castACTC)) {
3957	bool br = S.isKnownName(name: "CFBridgingRetain");
3958	S.Diag(loc, diag::err_arc_cast_requires_bridge)
3959	<< convKindForDiag
3960	<< unsigned(castExprType->isBlockPointerType()) // of ObjC|block type
3961	<< castExprType
3962	<< 2 // to C pointer type
3963	<< castType
3964	<< castRange
3965	<< castExpr->getSourceRange();
3966	ACCResult CreateRule =
3967	ARCCastChecker(S.Context, exprACTC, castACTC, true).Visit(e: castExpr);
3968	assert(CreateRule != ACC_bottom && "This cast should already be accepted.");
3969	if (CreateRule != ACC_plusOne)
3970	{
3971	auto DiagB = (CCK != CheckedConversionKind::OtherCast)
3972	? S.Diag(noteLoc, diag::note_arc_bridge)
3973	: S.Diag(noteLoc, diag::note_arc_cstyle_bridge);
3974	addFixitForObjCARCConversion(S, DiagB, CCK, afterLParen,
3975	castType, castExpr, realCast, "__bridge ",
3976	nullptr);
3977	}
3978	if (CreateRule != ACC_plusZero)
3979	{
3980	auto DiagB = (CCK == CheckedConversionKind::OtherCast && !br)
3981	? S.Diag(noteLoc, diag::note_arc_cstyle_bridge_retained)
3982	<< castType
3983	: S.Diag(br ? castExpr->getExprLoc() : noteLoc,
3984	diag::note_arc_bridge_retained)
3985	<< castType << br;
3986
3987	addFixitForObjCARCConversion(S, DiagB, CCK, afterLParen,
3988	castType, castExpr, realCast, "__bridge_retained ",
3989	br ? "CFBridgingRetain" : nullptr);
3990	}
3991
3992	return;
3993	}
3994
3995	S.Diag(loc, diag::err_arc_mismatched_cast)
3996	<< !convKindForDiag
3997	<< srcKind << castExprType << castType
3998	<< castRange << castExpr->getSourceRange();
3999	}
4000
4001	template <typename TB>
4002	static bool CheckObjCBridgeNSCast(Sema &S, QualType castType, Expr *castExpr,
4003	bool &HadTheAttribute, bool warn) {
4004	QualType T = castExpr->getType();
4005	HadTheAttribute = false;
4006	while (const auto *TD = T->getAs<TypedefType>()) {
4007	TypedefNameDecl *TDNDecl = TD->getDecl();
4008	if (TB *ObjCBAttr = getObjCBridgeAttr<TB>(TD)) {
4009	if (IdentifierInfo *Parm = ObjCBAttr->getBridgedType()) {
4010	HadTheAttribute = true;
4011	if (Parm->isStr(Str: "id"))
4012	return true;
4013
4014	// Check for an existing type with this name.
4015	LookupResult R(S, DeclarationName(Parm), SourceLocation(),
4016	Sema::LookupOrdinaryName);
4017	if (S.LookupName(R, S: S.TUScope)) {
4018	NamedDecl *Target = R.getFoundDecl();
4019	if (Target && isa<ObjCInterfaceDecl>(Val: Target)) {
4020	ObjCInterfaceDecl *ExprClass = cast<ObjCInterfaceDecl>(Val: Target);
4021	if (const ObjCObjectPointerType *InterfacePointerType =
4022	castType->getAsObjCInterfacePointerType()) {
4023	ObjCInterfaceDecl *CastClass
4024	= InterfacePointerType->getObjectType()->getInterface();
4025	if ((CastClass == ExprClass) ||
4026	(CastClass && CastClass->isSuperClassOf(I: ExprClass)))
4027	return true;
4028	if (warn)
4029	S.Diag(castExpr->getBeginLoc(), diag::warn_objc_invalid_bridge)
4030	<< T << Target->getName() << castType->getPointeeType();
4031	return false;
4032	} else if (castType->isObjCIdType() ||
4033	(S.Context.ObjCObjectAdoptsQTypeProtocols(
4034	QT: castType, Decl: ExprClass)))
4035	// ok to cast to 'id'.
4036	// casting to id<p-list> is ok if bridge type adopts all of
4037	// p-list protocols.
4038	return true;
4039	else {
4040	if (warn) {
4041	S.Diag(castExpr->getBeginLoc(), diag::warn_objc_invalid_bridge)
4042	<< T << Target->getName() << castType;
4043	S.Diag(TDNDecl->getBeginLoc(), diag::note_declared_at);
4044	S.Diag(Target->getBeginLoc(), diag::note_declared_at);
4045	}
4046	return false;
4047	}
4048	}
4049	} else if (!castType->isObjCIdType()) {
4050	S.Diag(castExpr->getBeginLoc(),
4051	diag::err_objc_cf_bridged_not_interface)
4052	<< castExpr->getType() << Parm;
4053	S.Diag(TDNDecl->getBeginLoc(), diag::note_declared_at);
4054	}
4055	return true;
4056	}
4057	return false;
4058	}
4059	T = TDNDecl->getUnderlyingType();
4060	}
4061	return true;
4062	}
4063
4064	template <typename TB>
4065	static bool CheckObjCBridgeCFCast(Sema &S, QualType castType, Expr *castExpr,
4066	bool &HadTheAttribute, bool warn) {
4067	QualType T = castType;
4068	HadTheAttribute = false;
4069	while (const auto *TD = T->getAs<TypedefType>()) {
4070	TypedefNameDecl *TDNDecl = TD->getDecl();
4071	if (TB *ObjCBAttr = getObjCBridgeAttr<TB>(TD)) {
4072	if (IdentifierInfo *Parm = ObjCBAttr->getBridgedType()) {
4073	HadTheAttribute = true;
4074	if (Parm->isStr(Str: "id"))
4075	return true;
4076
4077	NamedDecl *Target = nullptr;
4078	// Check for an existing type with this name.
4079	LookupResult R(S, DeclarationName(Parm), SourceLocation(),
4080	Sema::LookupOrdinaryName);
4081	if (S.LookupName(R, S: S.TUScope)) {
4082	Target = R.getFoundDecl();
4083	if (Target && isa<ObjCInterfaceDecl>(Val: Target)) {
4084	ObjCInterfaceDecl *CastClass = cast<ObjCInterfaceDecl>(Val: Target);
4085	if (const ObjCObjectPointerType *InterfacePointerType =
4086	castExpr->getType()->getAsObjCInterfacePointerType()) {
4087	ObjCInterfaceDecl *ExprClass
4088	= InterfacePointerType->getObjectType()->getInterface();
4089	if ((CastClass == ExprClass) ||
4090	(ExprClass && CastClass->isSuperClassOf(I: ExprClass)))
4091	return true;
4092	if (warn) {
4093	S.Diag(castExpr->getBeginLoc(),
4094	diag::warn_objc_invalid_bridge_to_cf)
4095	<< castExpr->getType()->getPointeeType() << T;
4096	S.Diag(TDNDecl->getBeginLoc(), diag::note_declared_at);
4097	}
4098	return false;
4099	} else if (castExpr->getType()->isObjCIdType() ||
4100	(S.Context.QIdProtocolsAdoptObjCObjectProtocols(
4101	QT: castExpr->getType(), IDecl: CastClass)))
4102	// ok to cast an 'id' expression to a CFtype.
4103	// ok to cast an 'id<plist>' expression to CFtype provided plist
4104	// adopts all of CFtype's ObjetiveC's class plist.
4105	return true;
4106	else {
4107	if (warn) {
4108	S.Diag(castExpr->getBeginLoc(),
4109	diag::warn_objc_invalid_bridge_to_cf)
4110	<< castExpr->getType() << castType;
4111	S.Diag(TDNDecl->getBeginLoc(), diag::note_declared_at);
4112	S.Diag(Target->getBeginLoc(), diag::note_declared_at);
4113	}
4114	return false;
4115	}
4116	}
4117	}
4118	S.Diag(castExpr->getBeginLoc(),
4119	diag::err_objc_ns_bridged_invalid_cfobject)
4120	<< castExpr->getType() << castType;
4121	S.Diag(TDNDecl->getBeginLoc(), diag::note_declared_at);
4122	if (Target)
4123	S.Diag(Target->getBeginLoc(), diag::note_declared_at);
4124	return true;
4125	}
4126	return false;
4127	}
4128	T = TDNDecl->getUnderlyingType();
4129	}
4130	return true;
4131	}
4132
4133	void Sema::CheckTollFreeBridgeCast(QualType castType, Expr *castExpr) {
4134	if (!getLangOpts().ObjC)
4135	return;
4136	// warn in presence of __bridge casting to or from a toll free bridge cast.
4137	ARCConversionTypeClass exprACTC = classifyTypeForARCConversion(type: castExpr->getType());
4138	ARCConversionTypeClass castACTC = classifyTypeForARCConversion(type: castType);
4139	if (castACTC == ACTC_retainable && exprACTC == ACTC_coreFoundation) {
4140	bool HasObjCBridgeAttr;
4141	bool ObjCBridgeAttrWillNotWarn =
4142	CheckObjCBridgeNSCast<ObjCBridgeAttr>(*this, castType, castExpr, HasObjCBridgeAttr,
4143	false);
4144	if (ObjCBridgeAttrWillNotWarn && HasObjCBridgeAttr)
4145	return;
4146	bool HasObjCBridgeMutableAttr;
4147	bool ObjCBridgeMutableAttrWillNotWarn =
4148	CheckObjCBridgeNSCast<ObjCBridgeMutableAttr>(*this, castType, castExpr,
4149	HasObjCBridgeMutableAttr, false);
4150	if (ObjCBridgeMutableAttrWillNotWarn && HasObjCBridgeMutableAttr)
4151	return;
4152
4153	if (HasObjCBridgeAttr)
4154	CheckObjCBridgeNSCast<ObjCBridgeAttr>(*this, castType, castExpr, HasObjCBridgeAttr,
4155	true);
4156	else if (HasObjCBridgeMutableAttr)
4157	CheckObjCBridgeNSCast<ObjCBridgeMutableAttr>(*this, castType, castExpr,
4158	HasObjCBridgeMutableAttr, true);
4159	}
4160	else if (castACTC == ACTC_coreFoundation && exprACTC == ACTC_retainable) {
4161	bool HasObjCBridgeAttr;
4162	bool ObjCBridgeAttrWillNotWarn =
4163	CheckObjCBridgeCFCast<ObjCBridgeAttr>(*this, castType, castExpr, HasObjCBridgeAttr,
4164	false);
4165	if (ObjCBridgeAttrWillNotWarn && HasObjCBridgeAttr)
4166	return;
4167	bool HasObjCBridgeMutableAttr;
4168	bool ObjCBridgeMutableAttrWillNotWarn =
4169	CheckObjCBridgeCFCast<ObjCBridgeMutableAttr>(*this, castType, castExpr,
4170	HasObjCBridgeMutableAttr, false);
4171	if (ObjCBridgeMutableAttrWillNotWarn && HasObjCBridgeMutableAttr)
4172	return;
4173
4174	if (HasObjCBridgeAttr)
4175	CheckObjCBridgeCFCast<ObjCBridgeAttr>(*this, castType, castExpr, HasObjCBridgeAttr,
4176	true);
4177	else if (HasObjCBridgeMutableAttr)
4178	CheckObjCBridgeCFCast<ObjCBridgeMutableAttr>(*this, castType, castExpr,
4179	HasObjCBridgeMutableAttr, true);
4180	}
4181	}
4182
4183	void Sema::CheckObjCBridgeRelatedCast(QualType castType, Expr *castExpr) {
4184	QualType SrcType = castExpr->getType();
4185	if (ObjCPropertyRefExpr *PRE = dyn_cast<ObjCPropertyRefExpr>(Val: castExpr)) {
4186	if (PRE->isExplicitProperty()) {
4187	if (ObjCPropertyDecl *PDecl = PRE->getExplicitProperty())
4188	SrcType = PDecl->getType();
4189	}
4190	else if (PRE->isImplicitProperty()) {
4191	if (ObjCMethodDecl *Getter = PRE->getImplicitPropertyGetter())
4192	SrcType = Getter->getReturnType();
4193	}
4194	}
4195
4196	ARCConversionTypeClass srcExprACTC = classifyTypeForARCConversion(type: SrcType);
4197	ARCConversionTypeClass castExprACTC = classifyTypeForARCConversion(type: castType);
4198	if (srcExprACTC != ACTC_retainable || castExprACTC != ACTC_coreFoundation)
4199	return;
4200	CheckObjCBridgeRelatedConversions(Loc: castExpr->getBeginLoc(), DestType: castType, SrcType,
4201	SrcExpr&: castExpr);
4202	}
4203
4204	bool Sema::CheckTollFreeBridgeStaticCast(QualType castType, Expr *castExpr,
4205	CastKind &Kind) {
4206	if (!getLangOpts().ObjC)
4207	return false;
4208	ARCConversionTypeClass exprACTC =
4209	classifyTypeForARCConversion(type: castExpr->getType());
4210	ARCConversionTypeClass castACTC = classifyTypeForARCConversion(type: castType);
4211	if ((castACTC == ACTC_retainable && exprACTC == ACTC_coreFoundation) ||
4212	(castACTC == ACTC_coreFoundation && exprACTC == ACTC_retainable)) {
4213	CheckTollFreeBridgeCast(castType, castExpr);
4214	Kind = (castACTC == ACTC_coreFoundation) ? CK_BitCast
4215	: CK_CPointerToObjCPointerCast;
4216	return true;
4217	}
4218	return false;
4219	}
4220
4221	bool Sema::checkObjCBridgeRelatedComponents(SourceLocation Loc,
4222	QualType DestType, QualType SrcType,
4223	ObjCInterfaceDecl *&RelatedClass,
4224	ObjCMethodDecl *&ClassMethod,
4225	ObjCMethodDecl *&InstanceMethod,
4226	TypedefNameDecl *&TDNDecl,
4227	bool CfToNs, bool Diagnose) {
4228	QualType T = CfToNs ? SrcType : DestType;
4229	ObjCBridgeRelatedAttr *ObjCBAttr = ObjCBridgeRelatedAttrFromType(T, TDNDecl);
4230	if (!ObjCBAttr)
4231	return false;
4232
4233	IdentifierInfo *RCId = ObjCBAttr->getRelatedClass();
4234	IdentifierInfo *CMId = ObjCBAttr->getClassMethod();
4235	IdentifierInfo *IMId = ObjCBAttr->getInstanceMethod();
4236	if (!RCId)
4237	return false;
4238	NamedDecl *Target = nullptr;
4239	// Check for an existing type with this name.
4240	LookupResult R(*this, DeclarationName(RCId), SourceLocation(),
4241	Sema::LookupOrdinaryName);
4242	if (!LookupName(R, S: TUScope)) {
4243	if (Diagnose) {
4244	Diag(Loc, diag::err_objc_bridged_related_invalid_class) << RCId
4245	<< SrcType << DestType;
4246	Diag(TDNDecl->getBeginLoc(), diag::note_declared_at);
4247	}
4248	return false;
4249	}
4250	Target = R.getFoundDecl();
4251	if (Target && isa<ObjCInterfaceDecl>(Val: Target))
4252	RelatedClass = cast<ObjCInterfaceDecl>(Val: Target);
4253	else {
4254	if (Diagnose) {
4255	Diag(Loc, diag::err_objc_bridged_related_invalid_class_name) << RCId
4256	<< SrcType << DestType;
4257	Diag(TDNDecl->getBeginLoc(), diag::note_declared_at);
4258	if (Target)
4259	Diag(Target->getBeginLoc(), diag::note_declared_at);
4260	}
4261	return false;
4262	}
4263
4264	// Check for an existing class method with the given selector name.
4265	if (CfToNs && CMId) {
4266	Selector Sel = Context.Selectors.getUnarySelector(ID: CMId);
4267	ClassMethod = RelatedClass->lookupMethod(Sel, isInstance: false);
4268	if (!ClassMethod) {
4269	if (Diagnose) {
4270	Diag(Loc, diag::err_objc_bridged_related_known_method)
4271	<< SrcType << DestType << Sel << false;
4272	Diag(TDNDecl->getBeginLoc(), diag::note_declared_at);
4273	}
4274	return false;
4275	}
4276	}
4277
4278	// Check for an existing instance method with the given selector name.
4279	if (!CfToNs && IMId) {
4280	Selector Sel = Context.Selectors.getNullarySelector(ID: IMId);
4281	InstanceMethod = RelatedClass->lookupMethod(Sel, isInstance: true);
4282	if (!InstanceMethod) {
4283	if (Diagnose) {
4284	Diag(Loc, diag::err_objc_bridged_related_known_method)
4285	<< SrcType << DestType << Sel << true;
4286	Diag(TDNDecl->getBeginLoc(), diag::note_declared_at);
4287	}
4288	return false;
4289	}
4290	}
4291	return true;
4292	}
4293
4294	bool
4295	Sema::CheckObjCBridgeRelatedConversions(SourceLocation Loc,
4296	QualType DestType, QualType SrcType,
4297	Expr *&SrcExpr, bool Diagnose) {
4298	ARCConversionTypeClass rhsExprACTC = classifyTypeForARCConversion(type: SrcType);
4299	ARCConversionTypeClass lhsExprACTC = classifyTypeForARCConversion(type: DestType);
4300	bool CfToNs = (rhsExprACTC == ACTC_coreFoundation && lhsExprACTC == ACTC_retainable);
4301	bool NsToCf = (rhsExprACTC == ACTC_retainable && lhsExprACTC == ACTC_coreFoundation);
4302	if (!CfToNs && !NsToCf)
4303	return false;
4304
4305	ObjCInterfaceDecl *RelatedClass;
4306	ObjCMethodDecl *ClassMethod = nullptr;
4307	ObjCMethodDecl *InstanceMethod = nullptr;
4308	TypedefNameDecl *TDNDecl = nullptr;
4309	if (!checkObjCBridgeRelatedComponents(Loc, DestType, SrcType, RelatedClass,
4310	ClassMethod, InstanceMethod, TDNDecl,
4311	CfToNs, Diagnose))
4312	return false;
4313
4314	if (CfToNs) {
4315	// Implicit conversion from CF to ObjC object is needed.
4316	if (ClassMethod) {
4317	if (Diagnose) {
4318	std::string ExpressionString = "[";
4319	ExpressionString += RelatedClass->getNameAsString();
4320	ExpressionString += " ";
4321	ExpressionString += ClassMethod->getSelector().getAsString();
4322	SourceLocation SrcExprEndLoc =
4323	getLocForEndOfToken(Loc: SrcExpr->getEndLoc());
4324	// Provide a fixit: [RelatedClass ClassMethod SrcExpr]
4325	Diag(Loc, diag::err_objc_bridged_related_known_method)
4326	<< SrcType << DestType << ClassMethod->getSelector() << false
4327	<< FixItHint::CreateInsertion(SrcExpr->getBeginLoc(),
4328	ExpressionString)
4329	<< FixItHint::CreateInsertion(SrcExprEndLoc, "]");
4330	Diag(RelatedClass->getBeginLoc(), diag::note_declared_at);
4331	Diag(TDNDecl->getBeginLoc(), diag::note_declared_at);
4332
4333	QualType receiverType = Context.getObjCInterfaceType(Decl: RelatedClass);
4334	// Argument.
4335	Expr *args[] = { SrcExpr };
4336	ExprResult msg = BuildClassMessageImplicit(ReceiverType: receiverType, isSuperReceiver: false,
4337	Loc: ClassMethod->getLocation(),
4338	Sel: ClassMethod->getSelector(), Method: ClassMethod,
4339	Args: MultiExprArg(args, 1));
4340	SrcExpr = msg.get();
4341	}
4342	return true;
4343	}
4344	}
4345	else {
4346	// Implicit conversion from ObjC type to CF object is needed.
4347	if (InstanceMethod) {
4348	if (Diagnose) {
4349	std::string ExpressionString;
4350	SourceLocation SrcExprEndLoc =
4351	getLocForEndOfToken(Loc: SrcExpr->getEndLoc());
4352	if (InstanceMethod->isPropertyAccessor())
4353	if (const ObjCPropertyDecl *PDecl =
4354	InstanceMethod->findPropertyDecl()) {
4355	// fixit: ObjectExpr.propertyname when it is aproperty accessor.
4356	ExpressionString = ".";
4357	ExpressionString += PDecl->getNameAsString();
4358	Diag(Loc, diag::err_objc_bridged_related_known_method)
4359	<< SrcType << DestType << InstanceMethod->getSelector() << true
4360	<< FixItHint::CreateInsertion(SrcExprEndLoc, ExpressionString);
4361	}
4362	if (ExpressionString.empty()) {
4363	// Provide a fixit: [ObjectExpr InstanceMethod]
4364	ExpressionString = " ";
4365	ExpressionString += InstanceMethod->getSelector().getAsString();
4366	ExpressionString += "]";
4367
4368	Diag(Loc, diag::err_objc_bridged_related_known_method)
4369	<< SrcType << DestType << InstanceMethod->getSelector() << true
4370	<< FixItHint::CreateInsertion(SrcExpr->getBeginLoc(), "[")
4371	<< FixItHint::CreateInsertion(SrcExprEndLoc, ExpressionString);
4372	}
4373	Diag(RelatedClass->getBeginLoc(), diag::note_declared_at);
4374	Diag(TDNDecl->getBeginLoc(), diag::note_declared_at);
4375
4376	ExprResult msg = BuildInstanceMessageImplicit(
4377	Receiver: SrcExpr, ReceiverType: SrcType, Loc: InstanceMethod->getLocation(),
4378	Sel: InstanceMethod->getSelector(), Method: InstanceMethod, Args: std::nullopt);
4379	SrcExpr = msg.get();
4380	}
4381	return true;
4382	}
4383	}
4384	return false;
4385	}
4386
4387	Sema::ARCConversionResult
4388	Sema::CheckObjCConversion(SourceRange castRange, QualType castType,
4389	Expr *&castExpr, CheckedConversionKind CCK,
4390	bool Diagnose, bool DiagnoseCFAudited,
4391	BinaryOperatorKind Opc) {
4392	QualType castExprType = castExpr->getType();
4393
4394	// For the purposes of the classification, we assume reference types
4395	// will bind to temporaries.
4396	QualType effCastType = castType;
4397	if (const ReferenceType *ref = castType->getAs<ReferenceType>())
4398	effCastType = ref->getPointeeType();
4399
4400	ARCConversionTypeClass exprACTC = classifyTypeForARCConversion(type: castExprType);
4401	ARCConversionTypeClass castACTC = classifyTypeForARCConversion(type: effCastType);
4402	if (exprACTC == castACTC) {
4403	// Check for viability and report error if casting an rvalue to a
4404	// life-time qualifier.
4405	if (castACTC == ACTC_retainable &&
4406	(CCK == CheckedConversionKind::CStyleCast ||
4407	CCK == CheckedConversionKind::OtherCast) &&
4408	castType != castExprType) {
4409	const Type *DT = castType.getTypePtr();
4410	QualType QDT = castType;
4411	// We desugar some types but not others. We ignore those
4412	// that cannot happen in a cast; i.e. auto, and those which
4413	// should not be de-sugared; i.e typedef.
4414	if (const ParenType *PT = dyn_cast<ParenType>(Val: DT))
4415	QDT = PT->desugar();
4416	else if (const TypeOfType *TP = dyn_cast<TypeOfType>(Val: DT))
4417	QDT = TP->desugar();
4418	else if (const AttributedType *AT = dyn_cast<AttributedType>(Val: DT))
4419	QDT = AT->desugar();
4420	if (QDT != castType &&
4421	QDT.getObjCLifetime() != Qualifiers::OCL_None) {
4422	if (Diagnose) {
4423	SourceLocation loc = (castRange.isValid() ? castRange.getBegin()
4424	: castExpr->getExprLoc());
4425	Diag(loc, diag::err_arc_nolifetime_behavior);
4426	}
4427	return ACR_error;
4428	}
4429	}
4430	return ACR_okay;
4431	}
4432
4433	// The life-time qualifier cast check above is all we need for ObjCWeak.
4434	// ObjCAutoRefCount has more restrictions on what is legal.
4435	if (!getLangOpts().ObjCAutoRefCount)
4436	return ACR_okay;
4437
4438	if (isAnyCLike(ACTC: exprACTC) && isAnyCLike(ACTC: castACTC)) return ACR_okay;
4439
4440	// Allow all of these types to be cast to integer types (but not
4441	// vice-versa).
4442	if (castACTC == ACTC_none && castType->isIntegralType(Ctx: Context))
4443	return ACR_okay;
4444
4445	// Allow casts between pointers to lifetime types (e.g., __strong id*)
4446	// and pointers to void (e.g., cv void *). Casting from void* to lifetime*
4447	// must be explicit.
4448	// Allow conversions between pointers to lifetime types and coreFoundation
4449	// pointers too, but only when the conversions are explicit.
4450	if (exprACTC == ACTC_indirectRetainable &&
4451	(castACTC == ACTC_voidPtr ||
4452	(castACTC == ACTC_coreFoundation && isCast(CCK))))
4453	return ACR_okay;
4454	if (castACTC == ACTC_indirectRetainable &&
4455	(exprACTC == ACTC_voidPtr || exprACTC == ACTC_coreFoundation) &&
4456	isCast(CCK))
4457	return ACR_okay;
4458
4459	switch (ARCCastChecker(Context, exprACTC, castACTC, false).Visit(e: castExpr)) {
4460	// For invalid casts, fall through.
4461	case ACC_invalid:
4462	break;
4463
4464	// Do nothing for both bottom and +0.
4465	case ACC_bottom:
4466	case ACC_plusZero:
4467	return ACR_okay;
4468
4469	// If the result is +1, consume it here.
4470	case ACC_plusOne:
4471	castExpr = ImplicitCastExpr::Create(Context, T: castExpr->getType(),
4472	Kind: CK_ARCConsumeObject, Operand: castExpr, BasePath: nullptr,
4473	Cat: VK_PRValue, FPO: FPOptionsOverride());
4474	Cleanup.setExprNeedsCleanups(true);
4475	return ACR_okay;
4476	}
4477
4478	// If this is a non-implicit cast from id or block type to a
4479	// CoreFoundation type, delay complaining in case the cast is used
4480	// in an acceptable context.
4481	if (exprACTC == ACTC_retainable && isAnyRetainable(ACTC: castACTC) && isCast(CCK))
4482	return ACR_unbridged;
4483
4484	// Issue a diagnostic about a missing @-sign when implicit casting a cstring
4485	// to 'NSString *', instead of falling through to report a "bridge cast"
4486	// diagnostic.
4487	if (castACTC == ACTC_retainable && exprACTC == ACTC_none &&
4488	CheckConversionToObjCLiteral(DstType: castType, SrcExpr&: castExpr, Diagnose))
4489	return ACR_error;
4490
4491	// Do not issue "bridge cast" diagnostic when implicit casting
4492	// a retainable object to a CF type parameter belonging to an audited
4493	// CF API function. Let caller issue a normal type mismatched diagnostic
4494	// instead.
4495	if ((!DiagnoseCFAudited || exprACTC != ACTC_retainable ||
4496	castACTC != ACTC_coreFoundation) &&
4497	!(exprACTC == ACTC_voidPtr && castACTC == ACTC_retainable &&
4498	(Opc == BO_NE || Opc == BO_EQ))) {
4499	if (Diagnose)
4500	diagnoseObjCARCConversion(S&: *this, castRange, castType, castACTC, castExpr,
4501	realCast: castExpr, exprACTC, CCK);
4502	return ACR_error;
4503	}
4504	return ACR_okay;
4505	}
4506
4507	/// Given that we saw an expression with the ARCUnbridgedCastTy
4508	/// placeholder type, complain bitterly.
4509	void Sema::diagnoseARCUnbridgedCast(Expr *e) {
4510	// We expect the spurious ImplicitCastExpr to already have been stripped.
4511	assert(!e->hasPlaceholderType(BuiltinType::ARCUnbridgedCast));
4512	CastExpr *realCast = cast<CastExpr>(Val: e->IgnoreParens());
4513
4514	SourceRange castRange;
4515	QualType castType;
4516	CheckedConversionKind CCK;
4517
4518	if (CStyleCastExpr *cast = dyn_cast<CStyleCastExpr>(Val: realCast)) {
4519	castRange = SourceRange(cast->getLParenLoc(), cast->getRParenLoc());
4520	castType = cast->getTypeAsWritten();
4521	CCK = CheckedConversionKind::CStyleCast;
4522	} else if (ExplicitCastExpr *cast = dyn_cast<ExplicitCastExpr>(Val: realCast)) {
4523	castRange = cast->getTypeInfoAsWritten()->getTypeLoc().getSourceRange();
4524	castType = cast->getTypeAsWritten();
4525	CCK = CheckedConversionKind::OtherCast;
4526	} else {
4527	llvm_unreachable("Unexpected ImplicitCastExpr");
4528	}
4529
4530	ARCConversionTypeClass castACTC =
4531	classifyTypeForARCConversion(type: castType.getNonReferenceType());
4532
4533	Expr *castExpr = realCast->getSubExpr();
4534	assert(classifyTypeForARCConversion(castExpr->getType()) == ACTC_retainable);
4535
4536	diagnoseObjCARCConversion(*this, castRange, castType, castACTC,
4537	castExpr, realCast, ACTC_retainable, CCK);
4538	}
4539
4540	/// stripARCUnbridgedCast - Given an expression of ARCUnbridgedCast
4541	/// type, remove the placeholder cast.
4542	Expr *Sema::stripARCUnbridgedCast(Expr *e) {
4543	assert(e->hasPlaceholderType(BuiltinType::ARCUnbridgedCast));
4544
4545	if (ParenExpr *pe = dyn_cast<ParenExpr>(Val: e)) {
4546	Expr *sub = stripARCUnbridgedCast(e: pe->getSubExpr());
4547	return new (Context) ParenExpr(pe->getLParen(), pe->getRParen(), sub);
4548	} else if (UnaryOperator *uo = dyn_cast<UnaryOperator>(Val: e)) {
4549	assert(uo->getOpcode() == UO_Extension);
4550	Expr *sub = stripARCUnbridgedCast(e: uo->getSubExpr());
4551	return UnaryOperator::Create(C: Context, input: sub, opc: UO_Extension, type: sub->getType(),
4552	VK: sub->getValueKind(), OK: sub->getObjectKind(),
4553	l: uo->getOperatorLoc(), CanOverflow: false,
4554	FPFeatures: CurFPFeatureOverrides());
4555	} else if (GenericSelectionExpr *gse = dyn_cast<GenericSelectionExpr>(Val: e)) {
4556	assert(!gse->isResultDependent());
4557	assert(!gse->isTypePredicate());
4558
4559	unsigned n = gse->getNumAssocs();
4560	SmallVector<Expr *, 4> subExprs;
4561	SmallVector<TypeSourceInfo *, 4> subTypes;
4562	subExprs.reserve(N: n);
4563	subTypes.reserve(N: n);
4564	for (const GenericSelectionExpr::Association assoc : gse->associations()) {
4565	subTypes.push_back(Elt: assoc.getTypeSourceInfo());
4566	Expr *sub = assoc.getAssociationExpr();
4567	if (assoc.isSelected())
4568	sub = stripARCUnbridgedCast(e: sub);
4569	subExprs.push_back(Elt: sub);
4570	}
4571
4572	return GenericSelectionExpr::Create(
4573	Context, gse->getGenericLoc(), gse->getControllingExpr(), subTypes,
4574	subExprs, gse->getDefaultLoc(), gse->getRParenLoc(),
4575	gse->containsUnexpandedParameterPack(), gse->getResultIndex());
4576	} else {
4577	assert(isa<ImplicitCastExpr>(e) && "bad form of unbridged cast!");
4578	return cast<ImplicitCastExpr>(Val: e)->getSubExpr();
4579	}
4580	}
4581
4582	bool Sema::CheckObjCARCUnavailableWeakConversion(QualType castType,
4583	QualType exprType) {
4584	QualType canCastType =
4585	Context.getCanonicalType(T: castType).getUnqualifiedType();
4586	QualType canExprType =
4587	Context.getCanonicalType(T: exprType).getUnqualifiedType();
4588	if (isa<ObjCObjectPointerType>(Val: canCastType) &&
4589	castType.getObjCLifetime() == Qualifiers::OCL_Weak &&
4590	canExprType->isObjCObjectPointerType()) {
4591	if (const ObjCObjectPointerType *ObjT =
4592	canExprType->getAs<ObjCObjectPointerType>())
4593	if (const ObjCInterfaceDecl *ObjI = ObjT->getInterfaceDecl())
4594	return !ObjI->isArcWeakrefUnavailable();
4595	}
4596	return true;
4597	}
4598
4599	/// Look for an ObjCReclaimReturnedObject cast and destroy it.
4600	static Expr *maybeUndoReclaimObject(Expr *e) {
4601	Expr *curExpr = e, *prevExpr = nullptr;
4602
4603	// Walk down the expression until we hit an implicit cast of kind
4604	// ARCReclaimReturnedObject or an Expr that is neither a Paren nor a Cast.
4605	while (true) {
4606	if (auto *pe = dyn_cast<ParenExpr>(Val: curExpr)) {
4607	prevExpr = curExpr;
4608	curExpr = pe->getSubExpr();
4609	continue;
4610	}
4611
4612	if (auto *ce = dyn_cast<CastExpr>(Val: curExpr)) {
4613	if (auto *ice = dyn_cast<ImplicitCastExpr>(Val: ce))
4614	if (ice->getCastKind() == CK_ARCReclaimReturnedObject) {
4615	if (!prevExpr)
4616	return ice->getSubExpr();
4617	if (auto *pe = dyn_cast<ParenExpr>(Val: prevExpr))
4618	pe->setSubExpr(ice->getSubExpr());
4619	else
4620	cast<CastExpr>(Val: prevExpr)->setSubExpr(ice->getSubExpr());
4621	return e;
4622	}
4623
4624	prevExpr = curExpr;
4625	curExpr = ce->getSubExpr();
4626	continue;
4627	}
4628
4629	// Break out of the loop if curExpr is neither a Paren nor a Cast.
4630	break;
4631	}
4632
4633	return e;
4634	}
4635
4636	ExprResult Sema::BuildObjCBridgedCast(SourceLocation LParenLoc,
4637	ObjCBridgeCastKind Kind,
4638	SourceLocation BridgeKeywordLoc,
4639	TypeSourceInfo *TSInfo,
4640	Expr *SubExpr) {
4641	ExprResult SubResult = UsualUnaryConversions(E: SubExpr);
4642	if (SubResult.isInvalid()) return ExprError();
4643	SubExpr = SubResult.get();
4644
4645	QualType T = TSInfo->getType();
4646	QualType FromType = SubExpr->getType();
4647
4648	CastKind CK;
4649
4650	bool MustConsume = false;
4651	if (T->isDependentType() || SubExpr->isTypeDependent()) {
4652	// Okay: we'll build a dependent expression type.
4653	CK = CK_Dependent;
4654	} else if (T->isObjCARCBridgableType() && FromType->isCARCBridgableType()) {
4655	// Casting CF -> id
4656	CK = (T->isBlockPointerType() ? CK_AnyPointerToBlockPointerCast
4657	: CK_CPointerToObjCPointerCast);
4658	switch (Kind) {
4659	case OBC_Bridge:
4660	break;
4661
4662	case OBC_BridgeRetained: {
4663	bool br = isKnownName(name: "CFBridgingRelease");
4664	Diag(BridgeKeywordLoc, diag::err_arc_bridge_cast_wrong_kind)
4665	<< 2
4666	<< FromType
4667	<< (T->isBlockPointerType()? 1 : 0)
4668	<< T
4669	<< SubExpr->getSourceRange()
4670	<< Kind;
4671	Diag(BridgeKeywordLoc, diag::note_arc_bridge)
4672	<< FixItHint::CreateReplacement(BridgeKeywordLoc, "__bridge");
4673	Diag(BridgeKeywordLoc, diag::note_arc_bridge_transfer)
4674	<< FromType << br
4675	<< FixItHint::CreateReplacement(BridgeKeywordLoc,
4676	br ? "CFBridgingRelease "
4677	: "__bridge_transfer ");
4678
4679	Kind = OBC_Bridge;
4680	break;
4681	}
4682
4683	case OBC_BridgeTransfer:
4684	// We must consume the Objective-C object produced by the cast.
4685	MustConsume = true;
4686	break;
4687	}
4688	} else if (T->isCARCBridgableType() && FromType->isObjCARCBridgableType()) {
4689	// Okay: id -> CF
4690	CK = CK_BitCast;
4691	switch (Kind) {
4692	case OBC_Bridge:
4693	// Reclaiming a value that's going to be __bridge-casted to CF
4694	// is very dangerous, so we don't do it.
4695	SubExpr = maybeUndoReclaimObject(e: SubExpr);
4696	break;
4697
4698	case OBC_BridgeRetained:
4699	// Produce the object before casting it.
4700	SubExpr = ImplicitCastExpr::Create(Context, T: FromType, Kind: CK_ARCProduceObject,
4701	Operand: SubExpr, BasePath: nullptr, Cat: VK_PRValue,
4702	FPO: FPOptionsOverride());
4703	break;
4704
4705	case OBC_BridgeTransfer: {
4706	bool br = isKnownName(name: "CFBridgingRetain");
4707	Diag(BridgeKeywordLoc, diag::err_arc_bridge_cast_wrong_kind)
4708	<< (FromType->isBlockPointerType()? 1 : 0)
4709	<< FromType
4710	<< 2
4711	<< T
4712	<< SubExpr->getSourceRange()
4713	<< Kind;
4714
4715	Diag(BridgeKeywordLoc, diag::note_arc_bridge)
4716	<< FixItHint::CreateReplacement(BridgeKeywordLoc, "__bridge ");
4717	Diag(BridgeKeywordLoc, diag::note_arc_bridge_retained)
4718	<< T << br
4719	<< FixItHint::CreateReplacement(BridgeKeywordLoc,
4720	br ? "CFBridgingRetain " : "__bridge_retained");
4721
4722	Kind = OBC_Bridge;
4723	break;
4724	}
4725	}
4726	} else {
4727	Diag(LParenLoc, diag::err_arc_bridge_cast_incompatible)
4728	<< FromType << T << Kind
4729	<< SubExpr->getSourceRange()
4730	<< TSInfo->getTypeLoc().getSourceRange();
4731	return ExprError();
4732	}
4733
4734	Expr *Result = new (Context) ObjCBridgedCastExpr(LParenLoc, Kind, CK,
4735	BridgeKeywordLoc,
4736	TSInfo, SubExpr);
4737
4738	if (MustConsume) {
4739	Cleanup.setExprNeedsCleanups(true);
4740	Result = ImplicitCastExpr::Create(Context, T, Kind: CK_ARCConsumeObject, Operand: Result,
4741	BasePath: nullptr, Cat: VK_PRValue, FPO: FPOptionsOverride());
4742	}
4743
4744	return Result;
4745	}
4746
4747	ExprResult Sema::ActOnObjCBridgedCast(Scope *S,
4748	SourceLocation LParenLoc,
4749	ObjCBridgeCastKind Kind,
4750	SourceLocation BridgeKeywordLoc,
4751	ParsedType Type,
4752	SourceLocation RParenLoc,
4753	Expr *SubExpr) {
4754	TypeSourceInfo *TSInfo = nullptr;
4755	QualType T = GetTypeFromParser(Ty: Type, TInfo: &TSInfo);
4756	if (Kind == OBC_Bridge)
4757	CheckTollFreeBridgeCast(castType: T, castExpr: SubExpr);
4758	if (!TSInfo)
4759	TSInfo = Context.getTrivialTypeSourceInfo(T, Loc: LParenLoc);
4760	return BuildObjCBridgedCast(LParenLoc, Kind, BridgeKeywordLoc, TSInfo,
4761	SubExpr);
4762	}
4763