Bug Summary

File:build/source/clang/lib/CodeGen/CGObjC.cpp
Warning:line 3204, column 3
Undefined or garbage value returned to caller

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name CGObjC.cpp -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/source/build-llvm -resource-dir /usr/lib/llvm-17/lib/clang/17 -I tools/clang/lib/CodeGen -I /build/source/clang/lib/CodeGen -I /build/source/clang/include -I tools/clang/include -I include -I /build/source/llvm/include -D _DEBUG -D _GLIBCXX_ASSERTIONS -D _GNU_SOURCE -D _LIBCPP_ENABLE_ASSERTIONS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -D _FORTIFY_SOURCE=2 -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-17/lib/clang/17/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/build/source/build-llvm=build-llvm -fmacro-prefix-map=/build/source/= -fcoverage-prefix-map=/build/source/build-llvm=build-llvm -fcoverage-prefix-map=/build/source/= -O3 -Wno-unused-command-line-argument -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -Wno-misleading-indentation -std=c++17 -fdeprecated-macro -fdebug-compilation-dir=/build/source/build-llvm -fdebug-prefix-map=/build/source/build-llvm=build-llvm -fdebug-prefix-map=/build/source/= -fdebug-prefix-map=/build/source/build-llvm=build-llvm -fdebug-prefix-map=/build/source/= -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2023-05-10-133810-16478-1 -x c++ /build/source/clang/lib/CodeGen/CGObjC.cpp
1//===---- CGObjC.cpp - Emit LLVM Code for Objective-C ---------------------===//
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 contains code to emit Objective-C code as LLVM code.
10//
11//===----------------------------------------------------------------------===//
12
13#include "CGDebugInfo.h"
14#include "CGObjCRuntime.h"
15#include "CodeGenFunction.h"
16#include "CodeGenModule.h"
17#include "ConstantEmitter.h"
18#include "TargetInfo.h"
19#include "clang/AST/ASTContext.h"
20#include "clang/AST/Attr.h"
21#include "clang/AST/DeclObjC.h"
22#include "clang/AST/StmtObjC.h"
23#include "clang/Basic/Diagnostic.h"
24#include "clang/CodeGen/CGFunctionInfo.h"
25#include "clang/CodeGen/CodeGenABITypes.h"
26#include "llvm/ADT/STLExtras.h"
27#include "llvm/Analysis/ObjCARCUtil.h"
28#include "llvm/BinaryFormat/MachO.h"
29#include "llvm/IR/Constants.h"
30#include "llvm/IR/DataLayout.h"
31#include "llvm/IR/InlineAsm.h"
32#include <optional>
33using namespace clang;
34using namespace CodeGen;
35
36typedef llvm::PointerIntPair<llvm::Value*,1,bool> TryEmitResult;
37static TryEmitResult
38tryEmitARCRetainScalarExpr(CodeGenFunction &CGF, const Expr *e);
39static RValue AdjustObjCObjectType(CodeGenFunction &CGF,
40 QualType ET,
41 RValue Result);
42
43/// Given the address of a variable of pointer type, find the correct
44/// null to store into it.
45static llvm::Constant *getNullForVariable(Address addr) {
46 llvm::Type *type = addr.getElementType();
47 return llvm::ConstantPointerNull::get(cast<llvm::PointerType>(type));
48}
49
50/// Emits an instance of NSConstantString representing the object.
51llvm::Value *CodeGenFunction::EmitObjCStringLiteral(const ObjCStringLiteral *E)
52{
53 llvm::Constant *C =
54 CGM.getObjCRuntime().GenerateConstantString(E->getString()).getPointer();
55 // FIXME: This bitcast should just be made an invariant on the Runtime.
56 return llvm::ConstantExpr::getBitCast(C, ConvertType(E->getType()));
57}
58
59/// EmitObjCBoxedExpr - This routine generates code to call
60/// the appropriate expression boxing method. This will either be
61/// one of +[NSNumber numberWith<Type>:], or +[NSString stringWithUTF8String:],
62/// or [NSValue valueWithBytes:objCType:].
63///
64llvm::Value *
65CodeGenFunction::EmitObjCBoxedExpr(const ObjCBoxedExpr *E) {
66 // Generate the correct selector for this literal's concrete type.
67 // Get the method.
68 const ObjCMethodDecl *BoxingMethod = E->getBoxingMethod();
69 const Expr *SubExpr = E->getSubExpr();
70
71 if (E->isExpressibleAsConstantInitializer()) {
72 ConstantEmitter ConstEmitter(CGM);
73 return ConstEmitter.tryEmitAbstract(E, E->getType());
74 }
75
76 assert(BoxingMethod->isClassMethod() && "BoxingMethod must be a class method")(static_cast <bool> (BoxingMethod->isClassMethod() &&
"BoxingMethod must be a class method") ? void (0) : __assert_fail
("BoxingMethod->isClassMethod() && \"BoxingMethod must be a class method\""
, "clang/lib/CodeGen/CGObjC.cpp", 76, __extension__ __PRETTY_FUNCTION__
))
;
77 Selector Sel = BoxingMethod->getSelector();
78
79 // Generate a reference to the class pointer, which will be the receiver.
80 // Assumes that the method was introduced in the class that should be
81 // messaged (avoids pulling it out of the result type).
82 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
83 const ObjCInterfaceDecl *ClassDecl = BoxingMethod->getClassInterface();
84 llvm::Value *Receiver = Runtime.GetClass(*this, ClassDecl);
85
86 CallArgList Args;
87 const ParmVarDecl *ArgDecl = *BoxingMethod->param_begin();
88 QualType ArgQT = ArgDecl->getType().getUnqualifiedType();
89
90 // ObjCBoxedExpr supports boxing of structs and unions
91 // via [NSValue valueWithBytes:objCType:]
92 const QualType ValueType(SubExpr->getType().getCanonicalType());
93 if (ValueType->isObjCBoxableRecordType()) {
94 // Emit CodeGen for first parameter
95 // and cast value to correct type
96 Address Temporary = CreateMemTemp(SubExpr->getType());
97 EmitAnyExprToMem(SubExpr, Temporary, Qualifiers(), /*isInit*/ true);
98 llvm::Value *BitCast =
99 Builder.CreateBitCast(Temporary.getPointer(), ConvertType(ArgQT));
100 Args.add(RValue::get(BitCast), ArgQT);
101
102 // Create char array to store type encoding
103 std::string Str;
104 getContext().getObjCEncodingForType(ValueType, Str);
105 llvm::Constant *GV = CGM.GetAddrOfConstantCString(Str).getPointer();
106
107 // Cast type encoding to correct type
108 const ParmVarDecl *EncodingDecl = BoxingMethod->parameters()[1];
109 QualType EncodingQT = EncodingDecl->getType().getUnqualifiedType();
110 llvm::Value *Cast = Builder.CreateBitCast(GV, ConvertType(EncodingQT));
111
112 Args.add(RValue::get(Cast), EncodingQT);
113 } else {
114 Args.add(EmitAnyExpr(SubExpr), ArgQT);
115 }
116
117 RValue result = Runtime.GenerateMessageSend(
118 *this, ReturnValueSlot(), BoxingMethod->getReturnType(), Sel, Receiver,
119 Args, ClassDecl, BoxingMethod);
120 return Builder.CreateBitCast(result.getScalarVal(),
121 ConvertType(E->getType()));
122}
123
124llvm::Value *CodeGenFunction::EmitObjCCollectionLiteral(const Expr *E,
125 const ObjCMethodDecl *MethodWithObjects) {
126 ASTContext &Context = CGM.getContext();
127 const ObjCDictionaryLiteral *DLE = nullptr;
128 const ObjCArrayLiteral *ALE = dyn_cast<ObjCArrayLiteral>(E);
129 if (!ALE)
130 DLE = cast<ObjCDictionaryLiteral>(E);
131
132 // Optimize empty collections by referencing constants, when available.
133 uint64_t NumElements =
134 ALE ? ALE->getNumElements() : DLE->getNumElements();
135 if (NumElements == 0 && CGM.getLangOpts().ObjCRuntime.hasEmptyCollections()) {
136 StringRef ConstantName = ALE ? "__NSArray0__" : "__NSDictionary0__";
137 QualType IdTy(CGM.getContext().getObjCIdType());
138 llvm::Constant *Constant =
139 CGM.CreateRuntimeVariable(ConvertType(IdTy), ConstantName);
140 LValue LV = MakeNaturalAlignAddrLValue(Constant, IdTy);
141 llvm::Value *Ptr = EmitLoadOfScalar(LV, E->getBeginLoc());
142 cast<llvm::LoadInst>(Ptr)->setMetadata(
143 CGM.getModule().getMDKindID("invariant.load"),
144 llvm::MDNode::get(getLLVMContext(), std::nullopt));
145 return Builder.CreateBitCast(Ptr, ConvertType(E->getType()));
146 }
147
148 // Compute the type of the array we're initializing.
149 llvm::APInt APNumElements(Context.getTypeSize(Context.getSizeType()),
150 NumElements);
151 QualType ElementType = Context.getObjCIdType().withConst();
152 QualType ElementArrayType
153 = Context.getConstantArrayType(ElementType, APNumElements, nullptr,
154 ArrayType::Normal, /*IndexTypeQuals=*/0);
155
156 // Allocate the temporary array(s).
157 Address Objects = CreateMemTemp(ElementArrayType, "objects");
158 Address Keys = Address::invalid();
159 if (DLE)
160 Keys = CreateMemTemp(ElementArrayType, "keys");
161
162 // In ARC, we may need to do extra work to keep all the keys and
163 // values alive until after the call.
164 SmallVector<llvm::Value *, 16> NeededObjects;
165 bool TrackNeededObjects =
166 (getLangOpts().ObjCAutoRefCount &&
167 CGM.getCodeGenOpts().OptimizationLevel != 0);
168
169 // Perform the actual initialialization of the array(s).
170 for (uint64_t i = 0; i < NumElements; i++) {
171 if (ALE) {
172 // Emit the element and store it to the appropriate array slot.
173 const Expr *Rhs = ALE->getElement(i);
174 LValue LV = MakeAddrLValue(Builder.CreateConstArrayGEP(Objects, i),
175 ElementType, AlignmentSource::Decl);
176
177 llvm::Value *value = EmitScalarExpr(Rhs);
178 EmitStoreThroughLValue(RValue::get(value), LV, true);
179 if (TrackNeededObjects) {
180 NeededObjects.push_back(value);
181 }
182 } else {
183 // Emit the key and store it to the appropriate array slot.
184 const Expr *Key = DLE->getKeyValueElement(i).Key;
185 LValue KeyLV = MakeAddrLValue(Builder.CreateConstArrayGEP(Keys, i),
186 ElementType, AlignmentSource::Decl);
187 llvm::Value *keyValue = EmitScalarExpr(Key);
188 EmitStoreThroughLValue(RValue::get(keyValue), KeyLV, /*isInit=*/true);
189
190 // Emit the value and store it to the appropriate array slot.
191 const Expr *Value = DLE->getKeyValueElement(i).Value;
192 LValue ValueLV = MakeAddrLValue(Builder.CreateConstArrayGEP(Objects, i),
193 ElementType, AlignmentSource::Decl);
194 llvm::Value *valueValue = EmitScalarExpr(Value);
195 EmitStoreThroughLValue(RValue::get(valueValue), ValueLV, /*isInit=*/true);
196 if (TrackNeededObjects) {
197 NeededObjects.push_back(keyValue);
198 NeededObjects.push_back(valueValue);
199 }
200 }
201 }
202
203 // Generate the argument list.
204 CallArgList Args;
205 ObjCMethodDecl::param_const_iterator PI = MethodWithObjects->param_begin();
206 const ParmVarDecl *argDecl = *PI++;
207 QualType ArgQT = argDecl->getType().getUnqualifiedType();
208 Args.add(RValue::get(Objects.getPointer()), ArgQT);
209 if (DLE) {
210 argDecl = *PI++;
211 ArgQT = argDecl->getType().getUnqualifiedType();
212 Args.add(RValue::get(Keys.getPointer()), ArgQT);
213 }
214 argDecl = *PI;
215 ArgQT = argDecl->getType().getUnqualifiedType();
216 llvm::Value *Count =
217 llvm::ConstantInt::get(CGM.getTypes().ConvertType(ArgQT), NumElements);
218 Args.add(RValue::get(Count), ArgQT);
219
220 // Generate a reference to the class pointer, which will be the receiver.
221 Selector Sel = MethodWithObjects->getSelector();
222 QualType ResultType = E->getType();
223 const ObjCObjectPointerType *InterfacePointerType
224 = ResultType->getAsObjCInterfacePointerType();
225 ObjCInterfaceDecl *Class
226 = InterfacePointerType->getObjectType()->getInterface();
227 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
228 llvm::Value *Receiver = Runtime.GetClass(*this, Class);
229
230 // Generate the message send.
231 RValue result = Runtime.GenerateMessageSend(
232 *this, ReturnValueSlot(), MethodWithObjects->getReturnType(), Sel,
233 Receiver, Args, Class, MethodWithObjects);
234
235 // The above message send needs these objects, but in ARC they are
236 // passed in a buffer that is essentially __unsafe_unretained.
237 // Therefore we must prevent the optimizer from releasing them until
238 // after the call.
239 if (TrackNeededObjects) {
240 EmitARCIntrinsicUse(NeededObjects);
241 }
242
243 return Builder.CreateBitCast(result.getScalarVal(),
244 ConvertType(E->getType()));
245}
246
247llvm::Value *CodeGenFunction::EmitObjCArrayLiteral(const ObjCArrayLiteral *E) {
248 return EmitObjCCollectionLiteral(E, E->getArrayWithObjectsMethod());
249}
250
251llvm::Value *CodeGenFunction::EmitObjCDictionaryLiteral(
252 const ObjCDictionaryLiteral *E) {
253 return EmitObjCCollectionLiteral(E, E->getDictWithObjectsMethod());
254}
255
256/// Emit a selector.
257llvm::Value *CodeGenFunction::EmitObjCSelectorExpr(const ObjCSelectorExpr *E) {
258 // Untyped selector.
259 // Note that this implementation allows for non-constant strings to be passed
260 // as arguments to @selector(). Currently, the only thing preventing this
261 // behaviour is the type checking in the front end.
262 return CGM.getObjCRuntime().GetSelector(*this, E->getSelector());
263}
264
265llvm::Value *CodeGenFunction::EmitObjCProtocolExpr(const ObjCProtocolExpr *E) {
266 // FIXME: This should pass the Decl not the name.
267 return CGM.getObjCRuntime().GenerateProtocolRef(*this, E->getProtocol());
268}
269
270/// Adjust the type of an Objective-C object that doesn't match up due
271/// to type erasure at various points, e.g., related result types or the use
272/// of parameterized classes.
273static RValue AdjustObjCObjectType(CodeGenFunction &CGF, QualType ExpT,
274 RValue Result) {
275 if (!ExpT->isObjCRetainableType())
276 return Result;
277
278 // If the converted types are the same, we're done.
279 llvm::Type *ExpLLVMTy = CGF.ConvertType(ExpT);
280 if (ExpLLVMTy == Result.getScalarVal()->getType())
281 return Result;
282
283 // We have applied a substitution. Cast the rvalue appropriately.
284 return RValue::get(CGF.Builder.CreateBitCast(Result.getScalarVal(),
285 ExpLLVMTy));
286}
287
288/// Decide whether to extend the lifetime of the receiver of a
289/// returns-inner-pointer message.
290static bool
291shouldExtendReceiverForInnerPointerMessage(const ObjCMessageExpr *message) {
292 switch (message->getReceiverKind()) {
293
294 // For a normal instance message, we should extend unless the
295 // receiver is loaded from a variable with precise lifetime.
296 case ObjCMessageExpr::Instance: {
297 const Expr *receiver = message->getInstanceReceiver();
298
299 // Look through OVEs.
300 if (auto opaque = dyn_cast<OpaqueValueExpr>(receiver)) {
301 if (opaque->getSourceExpr())
302 receiver = opaque->getSourceExpr()->IgnoreParens();
303 }
304
305 const ImplicitCastExpr *ice = dyn_cast<ImplicitCastExpr>(receiver);
306 if (!ice || ice->getCastKind() != CK_LValueToRValue) return true;
307 receiver = ice->getSubExpr()->IgnoreParens();
308
309 // Look through OVEs.
310 if (auto opaque = dyn_cast<OpaqueValueExpr>(receiver)) {
311 if (opaque->getSourceExpr())
312 receiver = opaque->getSourceExpr()->IgnoreParens();
313 }
314
315 // Only __strong variables.
316 if (receiver->getType().getObjCLifetime() != Qualifiers::OCL_Strong)
317 return true;
318
319 // All ivars and fields have precise lifetime.
320 if (isa<MemberExpr>(receiver) || isa<ObjCIvarRefExpr>(receiver))
321 return false;
322
323 // Otherwise, check for variables.
324 const DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(ice->getSubExpr());
325 if (!declRef) return true;
326 const VarDecl *var = dyn_cast<VarDecl>(declRef->getDecl());
327 if (!var) return true;
328
329 // All variables have precise lifetime except local variables with
330 // automatic storage duration that aren't specially marked.
331 return (var->hasLocalStorage() &&
332 !var->hasAttr<ObjCPreciseLifetimeAttr>());
333 }
334
335 case ObjCMessageExpr::Class:
336 case ObjCMessageExpr::SuperClass:
337 // It's never necessary for class objects.
338 return false;
339
340 case ObjCMessageExpr::SuperInstance:
341 // We generally assume that 'self' lives throughout a method call.
342 return false;
343 }
344
345 llvm_unreachable("invalid receiver kind")::llvm::llvm_unreachable_internal("invalid receiver kind", "clang/lib/CodeGen/CGObjC.cpp"
, 345)
;
346}
347
348/// Given an expression of ObjC pointer type, check whether it was
349/// immediately loaded from an ARC __weak l-value.
350static const Expr *findWeakLValue(const Expr *E) {
351 assert(E->getType()->isObjCRetainableType())(static_cast <bool> (E->getType()->isObjCRetainableType
()) ? void (0) : __assert_fail ("E->getType()->isObjCRetainableType()"
, "clang/lib/CodeGen/CGObjC.cpp", 351, __extension__ __PRETTY_FUNCTION__
))
;
352 E = E->IgnoreParens();
353 if (auto CE = dyn_cast<CastExpr>(E)) {
354 if (CE->getCastKind() == CK_LValueToRValue) {
355 if (CE->getSubExpr()->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
356 return CE->getSubExpr();
357 }
358 }
359
360 return nullptr;
361}
362
363/// The ObjC runtime may provide entrypoints that are likely to be faster
364/// than an ordinary message send of the appropriate selector.
365///
366/// The entrypoints are guaranteed to be equivalent to just sending the
367/// corresponding message. If the entrypoint is implemented naively as just a
368/// message send, using it is a trade-off: it sacrifices a few cycles of
369/// overhead to save a small amount of code. However, it's possible for
370/// runtimes to detect and special-case classes that use "standard"
371/// behavior; if that's dynamically a large proportion of all objects, using
372/// the entrypoint will also be faster than using a message send.
373///
374/// If the runtime does support a required entrypoint, then this method will
375/// generate a call and return the resulting value. Otherwise it will return
376/// std::nullopt and the caller can generate a msgSend instead.
377static std::optional<llvm::Value *> tryGenerateSpecializedMessageSend(
378 CodeGenFunction &CGF, QualType ResultType, llvm::Value *Receiver,
379 const CallArgList &Args, Selector Sel, const ObjCMethodDecl *method,
380 bool isClassMessage) {
381 auto &CGM = CGF.CGM;
382 if (!CGM.getCodeGenOpts().ObjCConvertMessagesToRuntimeCalls)
383 return std::nullopt;
384
385 auto &Runtime = CGM.getLangOpts().ObjCRuntime;
386 switch (Sel.getMethodFamily()) {
387 case OMF_alloc:
388 if (isClassMessage &&
389 Runtime.shouldUseRuntimeFunctionsForAlloc() &&
390 ResultType->isObjCObjectPointerType()) {
391 // [Foo alloc] -> objc_alloc(Foo) or
392 // [self alloc] -> objc_alloc(self)
393 if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "alloc")
394 return CGF.EmitObjCAlloc(Receiver, CGF.ConvertType(ResultType));
395 // [Foo allocWithZone:nil] -> objc_allocWithZone(Foo) or
396 // [self allocWithZone:nil] -> objc_allocWithZone(self)
397 if (Sel.isKeywordSelector() && Sel.getNumArgs() == 1 &&
398 Args.size() == 1 && Args.front().getType()->isPointerType() &&
399 Sel.getNameForSlot(0) == "allocWithZone") {
400 const llvm::Value* arg = Args.front().getKnownRValue().getScalarVal();
401 if (isa<llvm::ConstantPointerNull>(arg))
402 return CGF.EmitObjCAllocWithZone(Receiver,
403 CGF.ConvertType(ResultType));
404 return std::nullopt;
405 }
406 }
407 break;
408
409 case OMF_autorelease:
410 if (ResultType->isObjCObjectPointerType() &&
411 CGM.getLangOpts().getGC() == LangOptions::NonGC &&
412 Runtime.shouldUseARCFunctionsForRetainRelease())
413 return CGF.EmitObjCAutorelease(Receiver, CGF.ConvertType(ResultType));
414 break;
415
416 case OMF_retain:
417 if (ResultType->isObjCObjectPointerType() &&
418 CGM.getLangOpts().getGC() == LangOptions::NonGC &&
419 Runtime.shouldUseARCFunctionsForRetainRelease())
420 return CGF.EmitObjCRetainNonBlock(Receiver, CGF.ConvertType(ResultType));
421 break;
422
423 case OMF_release:
424 if (ResultType->isVoidType() &&
425 CGM.getLangOpts().getGC() == LangOptions::NonGC &&
426 Runtime.shouldUseARCFunctionsForRetainRelease()) {
427 CGF.EmitObjCRelease(Receiver, ARCPreciseLifetime);
428 return nullptr;
429 }
430 break;
431
432 default:
433 break;
434 }
435 return std::nullopt;
436}
437
438CodeGen::RValue CGObjCRuntime::GeneratePossiblySpecializedMessageSend(
439 CodeGenFunction &CGF, ReturnValueSlot Return, QualType ResultType,
440 Selector Sel, llvm::Value *Receiver, const CallArgList &Args,
441 const ObjCInterfaceDecl *OID, const ObjCMethodDecl *Method,
442 bool isClassMessage) {
443 if (std::optional<llvm::Value *> SpecializedResult =
444 tryGenerateSpecializedMessageSend(CGF, ResultType, Receiver, Args,
445 Sel, Method, isClassMessage)) {
446 return RValue::get(*SpecializedResult);
447 }
448 return GenerateMessageSend(CGF, Return, ResultType, Sel, Receiver, Args, OID,
449 Method);
450}
451
452static void AppendFirstImpliedRuntimeProtocols(
453 const ObjCProtocolDecl *PD,
454 llvm::UniqueVector<const ObjCProtocolDecl *> &PDs) {
455 if (!PD->isNonRuntimeProtocol()) {
456 const auto *Can = PD->getCanonicalDecl();
457 PDs.insert(Can);
458 return;
459 }
460
461 for (const auto *ParentPD : PD->protocols())
462 AppendFirstImpliedRuntimeProtocols(ParentPD, PDs);
463}
464
465std::vector<const ObjCProtocolDecl *>
466CGObjCRuntime::GetRuntimeProtocolList(ObjCProtocolDecl::protocol_iterator begin,
467 ObjCProtocolDecl::protocol_iterator end) {
468 std::vector<const ObjCProtocolDecl *> RuntimePds;
469 llvm::DenseSet<const ObjCProtocolDecl *> NonRuntimePDs;
470
471 for (; begin != end; ++begin) {
472 const auto *It = *begin;
473 const auto *Can = It->getCanonicalDecl();
474 if (Can->isNonRuntimeProtocol())
475 NonRuntimePDs.insert(Can);
476 else
477 RuntimePds.push_back(Can);
478 }
479
480 // If there are no non-runtime protocols then we can just stop now.
481 if (NonRuntimePDs.empty())
482 return RuntimePds;
483
484 // Else we have to search through the non-runtime protocol's inheritancy
485 // hierarchy DAG stopping whenever a branch either finds a runtime protocol or
486 // a non-runtime protocol without any parents. These are the "first-implied"
487 // protocols from a non-runtime protocol.
488 llvm::UniqueVector<const ObjCProtocolDecl *> FirstImpliedProtos;
489 for (const auto *PD : NonRuntimePDs)
490 AppendFirstImpliedRuntimeProtocols(PD, FirstImpliedProtos);
491
492 // Walk the Runtime list to get all protocols implied via the inclusion of
493 // this protocol, e.g. all protocols it inherits from including itself.
494 llvm::DenseSet<const ObjCProtocolDecl *> AllImpliedProtocols;
495 for (const auto *PD : RuntimePds) {
496 const auto *Can = PD->getCanonicalDecl();
497 AllImpliedProtocols.insert(Can);
498 Can->getImpliedProtocols(AllImpliedProtocols);
499 }
500
501 // Similar to above, walk the list of first-implied protocols to find the set
502 // all the protocols implied excluding the listed protocols themselves since
503 // they are not yet a part of the `RuntimePds` list.
504 for (const auto *PD : FirstImpliedProtos) {
505 PD->getImpliedProtocols(AllImpliedProtocols);
506 }
507
508 // From the first-implied list we have to finish building the final protocol
509 // list. If a protocol in the first-implied list was already implied via some
510 // inheritance path through some other protocols then it would be redundant to
511 // add it here and so we skip over it.
512 for (const auto *PD : FirstImpliedProtos) {
513 if (!AllImpliedProtocols.contains(PD)) {
514 RuntimePds.push_back(PD);
515 }
516 }
517
518 return RuntimePds;
519}
520
521/// Instead of '[[MyClass alloc] init]', try to generate
522/// 'objc_alloc_init(MyClass)'. This provides a code size improvement on the
523/// caller side, as well as the optimized objc_alloc.
524static std::optional<llvm::Value *>
525tryEmitSpecializedAllocInit(CodeGenFunction &CGF, const ObjCMessageExpr *OME) {
526 auto &Runtime = CGF.getLangOpts().ObjCRuntime;
527 if (!Runtime.shouldUseRuntimeFunctionForCombinedAllocInit())
528 return std::nullopt;
529
530 // Match the exact pattern '[[MyClass alloc] init]'.
531 Selector Sel = OME->getSelector();
532 if (OME->getReceiverKind() != ObjCMessageExpr::Instance ||
533 !OME->getType()->isObjCObjectPointerType() || !Sel.isUnarySelector() ||
534 Sel.getNameForSlot(0) != "init")
535 return std::nullopt;
536
537 // Okay, this is '[receiver init]', check if 'receiver' is '[cls alloc]'
538 // with 'cls' a Class.
539 auto *SubOME =
540 dyn_cast<ObjCMessageExpr>(OME->getInstanceReceiver()->IgnoreParenCasts());
541 if (!SubOME)
542 return std::nullopt;
543 Selector SubSel = SubOME->getSelector();
544
545 if (!SubOME->getType()->isObjCObjectPointerType() ||
546 !SubSel.isUnarySelector() || SubSel.getNameForSlot(0) != "alloc")
547 return std::nullopt;
548
549 llvm::Value *Receiver = nullptr;
550 switch (SubOME->getReceiverKind()) {
551 case ObjCMessageExpr::Instance:
552 if (!SubOME->getInstanceReceiver()->getType()->isObjCClassType())
553 return std::nullopt;
554 Receiver = CGF.EmitScalarExpr(SubOME->getInstanceReceiver());
555 break;
556
557 case ObjCMessageExpr::Class: {
558 QualType ReceiverType = SubOME->getClassReceiver();
559 const ObjCObjectType *ObjTy = ReceiverType->castAs<ObjCObjectType>();
560 const ObjCInterfaceDecl *ID = ObjTy->getInterface();
561 assert(ID && "null interface should be impossible here")(static_cast <bool> (ID && "null interface should be impossible here"
) ? void (0) : __assert_fail ("ID && \"null interface should be impossible here\""
, "clang/lib/CodeGen/CGObjC.cpp", 561, __extension__ __PRETTY_FUNCTION__
))
;
562 Receiver = CGF.CGM.getObjCRuntime().GetClass(CGF, ID);
563 break;
564 }
565 case ObjCMessageExpr::SuperInstance:
566 case ObjCMessageExpr::SuperClass:
567 return std::nullopt;
568 }
569
570 return CGF.EmitObjCAllocInit(Receiver, CGF.ConvertType(OME->getType()));
571}
572
573RValue CodeGenFunction::EmitObjCMessageExpr(const ObjCMessageExpr *E,
574 ReturnValueSlot Return) {
575 // Only the lookup mechanism and first two arguments of the method
576 // implementation vary between runtimes. We can get the receiver and
577 // arguments in generic code.
578
579 bool isDelegateInit = E->isDelegateInitCall();
580
581 const ObjCMethodDecl *method = E->getMethodDecl();
582
583 // If the method is -retain, and the receiver's being loaded from
584 // a __weak variable, peephole the entire operation to objc_loadWeakRetained.
585 if (method && E->getReceiverKind() == ObjCMessageExpr::Instance &&
586 method->getMethodFamily() == OMF_retain) {
587 if (auto lvalueExpr = findWeakLValue(E->getInstanceReceiver())) {
588 LValue lvalue = EmitLValue(lvalueExpr);
589 llvm::Value *result = EmitARCLoadWeakRetained(lvalue.getAddress(*this));
590 return AdjustObjCObjectType(*this, E->getType(), RValue::get(result));
591 }
592 }
593
594 if (std::optional<llvm::Value *> Val = tryEmitSpecializedAllocInit(*this, E))
595 return AdjustObjCObjectType(*this, E->getType(), RValue::get(*Val));
596
597 // We don't retain the receiver in delegate init calls, and this is
598 // safe because the receiver value is always loaded from 'self',
599 // which we zero out. We don't want to Block_copy block receivers,
600 // though.
601 bool retainSelf =
602 (!isDelegateInit &&
603 CGM.getLangOpts().ObjCAutoRefCount &&
604 method &&
605 method->hasAttr<NSConsumesSelfAttr>());
606
607 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
608 bool isSuperMessage = false;
609 bool isClassMessage = false;
610 ObjCInterfaceDecl *OID = nullptr;
611 // Find the receiver
612 QualType ReceiverType;
613 llvm::Value *Receiver = nullptr;
614 switch (E->getReceiverKind()) {
615 case ObjCMessageExpr::Instance:
616 ReceiverType = E->getInstanceReceiver()->getType();
617 isClassMessage = ReceiverType->isObjCClassType();
618 if (retainSelf) {
619 TryEmitResult ter = tryEmitARCRetainScalarExpr(*this,
620 E->getInstanceReceiver());
621 Receiver = ter.getPointer();
622 if (ter.getInt()) retainSelf = false;
623 } else
624 Receiver = EmitScalarExpr(E->getInstanceReceiver());
625 break;
626
627 case ObjCMessageExpr::Class: {
628 ReceiverType = E->getClassReceiver();
629 OID = ReceiverType->castAs<ObjCObjectType>()->getInterface();
630 assert(OID && "Invalid Objective-C class message send")(static_cast <bool> (OID && "Invalid Objective-C class message send"
) ? void (0) : __assert_fail ("OID && \"Invalid Objective-C class message send\""
, "clang/lib/CodeGen/CGObjC.cpp", 630, __extension__ __PRETTY_FUNCTION__
))
;
631 Receiver = Runtime.GetClass(*this, OID);
632 isClassMessage = true;
633 break;
634 }
635
636 case ObjCMessageExpr::SuperInstance:
637 ReceiverType = E->getSuperType();
638 Receiver = LoadObjCSelf();
639 isSuperMessage = true;
640 break;
641
642 case ObjCMessageExpr::SuperClass:
643 ReceiverType = E->getSuperType();
644 Receiver = LoadObjCSelf();
645 isSuperMessage = true;
646 isClassMessage = true;
647 break;
648 }
649
650 if (retainSelf)
651 Receiver = EmitARCRetainNonBlock(Receiver);
652
653 // In ARC, we sometimes want to "extend the lifetime"
654 // (i.e. retain+autorelease) of receivers of returns-inner-pointer
655 // messages.
656 if (getLangOpts().ObjCAutoRefCount && method &&
657 method->hasAttr<ObjCReturnsInnerPointerAttr>() &&
658 shouldExtendReceiverForInnerPointerMessage(E))
659 Receiver = EmitARCRetainAutorelease(ReceiverType, Receiver);
660
661 QualType ResultType = method ? method->getReturnType() : E->getType();
662
663 CallArgList Args;
664 EmitCallArgs(Args, method, E->arguments(), /*AC*/AbstractCallee(method));
665
666 // For delegate init calls in ARC, do an unsafe store of null into
667 // self. This represents the call taking direct ownership of that
668 // value. We have to do this after emitting the other call
669 // arguments because they might also reference self, but we don't
670 // have to worry about any of them modifying self because that would
671 // be an undefined read and write of an object in unordered
672 // expressions.
673 if (isDelegateInit) {
674 assert(getLangOpts().ObjCAutoRefCount &&(static_cast <bool> (getLangOpts().ObjCAutoRefCount &&
"delegate init calls should only be marked in ARC") ? void (
0) : __assert_fail ("getLangOpts().ObjCAutoRefCount && \"delegate init calls should only be marked in ARC\""
, "clang/lib/CodeGen/CGObjC.cpp", 675, __extension__ __PRETTY_FUNCTION__
))
675 "delegate init calls should only be marked in ARC")(static_cast <bool> (getLangOpts().ObjCAutoRefCount &&
"delegate init calls should only be marked in ARC") ? void (
0) : __assert_fail ("getLangOpts().ObjCAutoRefCount && \"delegate init calls should only be marked in ARC\""
, "clang/lib/CodeGen/CGObjC.cpp", 675, __extension__ __PRETTY_FUNCTION__
))
;
676
677 // Do an unsafe store of null into self.
678 Address selfAddr =
679 GetAddrOfLocalVar(cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl());
680 Builder.CreateStore(getNullForVariable(selfAddr), selfAddr);
681 }
682
683 RValue result;
684 if (isSuperMessage) {
685 // super is only valid in an Objective-C method
686 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
687 bool isCategoryImpl = isa<ObjCCategoryImplDecl>(OMD->getDeclContext());
688 result = Runtime.GenerateMessageSendSuper(*this, Return, ResultType,
689 E->getSelector(),
690 OMD->getClassInterface(),
691 isCategoryImpl,
692 Receiver,
693 isClassMessage,
694 Args,
695 method);
696 } else {
697 // Call runtime methods directly if we can.
698 result = Runtime.GeneratePossiblySpecializedMessageSend(
699 *this, Return, ResultType, E->getSelector(), Receiver, Args, OID,
700 method, isClassMessage);
701 }
702
703 // For delegate init calls in ARC, implicitly store the result of
704 // the call back into self. This takes ownership of the value.
705 if (isDelegateInit) {
706 Address selfAddr =
707 GetAddrOfLocalVar(cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl());
708 llvm::Value *newSelf = result.getScalarVal();
709
710 // The delegate return type isn't necessarily a matching type; in
711 // fact, it's quite likely to be 'id'.
712 llvm::Type *selfTy = selfAddr.getElementType();
713 newSelf = Builder.CreateBitCast(newSelf, selfTy);
714
715 Builder.CreateStore(newSelf, selfAddr);
716 }
717
718 return AdjustObjCObjectType(*this, E->getType(), result);
719}
720
721namespace {
722struct FinishARCDealloc final : EHScopeStack::Cleanup {
723 void Emit(CodeGenFunction &CGF, Flags flags) override {
724 const ObjCMethodDecl *method = cast<ObjCMethodDecl>(CGF.CurCodeDecl);
725
726 const ObjCImplDecl *impl = cast<ObjCImplDecl>(method->getDeclContext());
727 const ObjCInterfaceDecl *iface = impl->getClassInterface();
728 if (!iface->getSuperClass()) return;
729
730 bool isCategory = isa<ObjCCategoryImplDecl>(impl);
731
732 // Call [super dealloc] if we have a superclass.
733 llvm::Value *self = CGF.LoadObjCSelf();
734
735 CallArgList args;
736 CGF.CGM.getObjCRuntime().GenerateMessageSendSuper(CGF, ReturnValueSlot(),
737 CGF.getContext().VoidTy,
738 method->getSelector(),
739 iface,
740 isCategory,
741 self,
742 /*is class msg*/ false,
743 args,
744 method);
745 }
746};
747}
748
749/// StartObjCMethod - Begin emission of an ObjCMethod. This generates
750/// the LLVM function and sets the other context used by
751/// CodeGenFunction.
752void CodeGenFunction::StartObjCMethod(const ObjCMethodDecl *OMD,
753 const ObjCContainerDecl *CD) {
754 SourceLocation StartLoc = OMD->getBeginLoc();
755 FunctionArgList args;
756 // Check if we should generate debug info for this method.
757 if (OMD->hasAttr<NoDebugAttr>())
758 DebugInfo = nullptr; // disable debug info indefinitely for this function
759
760 llvm::Function *Fn = CGM.getObjCRuntime().GenerateMethod(OMD, CD);
761
762 const CGFunctionInfo &FI = CGM.getTypes().arrangeObjCMethodDeclaration(OMD);
763 if (OMD->isDirectMethod()) {
764 Fn->setVisibility(llvm::Function::HiddenVisibility);
765 CGM.SetLLVMFunctionAttributes(OMD, FI, Fn, /*IsThunk=*/false);
766 CGM.SetLLVMFunctionAttributesForDefinition(OMD, Fn);
767 } else {
768 CGM.SetInternalFunctionAttributes(OMD, Fn, FI);
769 }
770
771 args.push_back(OMD->getSelfDecl());
772 if (!OMD->isDirectMethod())
773 args.push_back(OMD->getCmdDecl());
774
775 args.append(OMD->param_begin(), OMD->param_end());
776
777 CurGD = OMD;
778 CurEHLocation = OMD->getEndLoc();
779
780 StartFunction(OMD, OMD->getReturnType(), Fn, FI, args,
781 OMD->getLocation(), StartLoc);
782
783 if (OMD->isDirectMethod()) {
784 // This function is a direct call, it has to implement a nil check
785 // on entry.
786 //
787 // TODO: possibly have several entry points to elide the check
788 CGM.getObjCRuntime().GenerateDirectMethodPrologue(*this, Fn, OMD, CD);
789 }
790
791 // In ARC, certain methods get an extra cleanup.
792 if (CGM.getLangOpts().ObjCAutoRefCount &&
793 OMD->isInstanceMethod() &&
794 OMD->getSelector().isUnarySelector()) {
795 const IdentifierInfo *ident =
796 OMD->getSelector().getIdentifierInfoForSlot(0);
797 if (ident->isStr("dealloc"))
798 EHStack.pushCleanup<FinishARCDealloc>(getARCCleanupKind());
799 }
800}
801
802static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF,
803 LValue lvalue, QualType type);
804
805/// Generate an Objective-C method. An Objective-C method is a C function with
806/// its pointer, name, and types registered in the class structure.
807void CodeGenFunction::GenerateObjCMethod(const ObjCMethodDecl *OMD) {
808 StartObjCMethod(OMD, OMD->getClassInterface());
809 PGO.assignRegionCounters(GlobalDecl(OMD), CurFn);
810 assert(isa<CompoundStmt>(OMD->getBody()))(static_cast <bool> (isa<CompoundStmt>(OMD->getBody
())) ? void (0) : __assert_fail ("isa<CompoundStmt>(OMD->getBody())"
, "clang/lib/CodeGen/CGObjC.cpp", 810, __extension__ __PRETTY_FUNCTION__
))
;
811 incrementProfileCounter(OMD->getBody());
812 EmitCompoundStmtWithoutScope(*cast<CompoundStmt>(OMD->getBody()));
813 FinishFunction(OMD->getBodyRBrace());
814}
815
816/// emitStructGetterCall - Call the runtime function to load a property
817/// into the return value slot.
818static void emitStructGetterCall(CodeGenFunction &CGF, ObjCIvarDecl *ivar,
819 bool isAtomic, bool hasStrong) {
820 ASTContext &Context = CGF.getContext();
821
822 llvm::Value *src =
823 CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), CGF.LoadObjCSelf(), ivar, 0)
824 .getPointer(CGF);
825
826 // objc_copyStruct (ReturnValue, &structIvar,
827 // sizeof (Type of Ivar), isAtomic, false);
828 CallArgList args;
829
830 llvm::Value *dest =
831 CGF.Builder.CreateBitCast(CGF.ReturnValue.getPointer(), CGF.VoidPtrTy);
832 args.add(RValue::get(dest), Context.VoidPtrTy);
833
834 src = CGF.Builder.CreateBitCast(src, CGF.VoidPtrTy);
835 args.add(RValue::get(src), Context.VoidPtrTy);
836
837 CharUnits size = CGF.getContext().getTypeSizeInChars(ivar->getType());
838 args.add(RValue::get(CGF.CGM.getSize(size)), Context.getSizeType());
839 args.add(RValue::get(CGF.Builder.getInt1(isAtomic)), Context.BoolTy);
840 args.add(RValue::get(CGF.Builder.getInt1(hasStrong)), Context.BoolTy);
841
842 llvm::FunctionCallee fn = CGF.CGM.getObjCRuntime().GetGetStructFunction();
843 CGCallee callee = CGCallee::forDirect(fn);
844 CGF.EmitCall(CGF.getTypes().arrangeBuiltinFunctionCall(Context.VoidTy, args),
845 callee, ReturnValueSlot(), args);
846}
847
848/// Determine whether the given architecture supports unaligned atomic
849/// accesses. They don't have to be fast, just faster than a function
850/// call and a mutex.
851static bool hasUnalignedAtomics(llvm::Triple::ArchType arch) {
852 // FIXME: Allow unaligned atomic load/store on x86. (It is not
853 // currently supported by the backend.)
854 return false;
855}
856
857/// Return the maximum size that permits atomic accesses for the given
858/// architecture.
859static CharUnits getMaxAtomicAccessSize(CodeGenModule &CGM,
860 llvm::Triple::ArchType arch) {
861 // ARM has 8-byte atomic accesses, but it's not clear whether we
862 // want to rely on them here.
863
864 // In the default case, just assume that any size up to a pointer is
865 // fine given adequate alignment.
866 return CharUnits::fromQuantity(CGM.PointerSizeInBytes);
867}
868
869namespace {
870 class PropertyImplStrategy {
871 public:
872 enum StrategyKind {
873 /// The 'native' strategy is to use the architecture's provided
874 /// reads and writes.
875 Native,
876
877 /// Use objc_setProperty and objc_getProperty.
878 GetSetProperty,
879
880 /// Use objc_setProperty for the setter, but use expression
881 /// evaluation for the getter.
882 SetPropertyAndExpressionGet,
883
884 /// Use objc_copyStruct.
885 CopyStruct,
886
887 /// The 'expression' strategy is to emit normal assignment or
888 /// lvalue-to-rvalue expressions.
889 Expression
890 };
891
892 StrategyKind getKind() const { return StrategyKind(Kind); }
893
894 bool hasStrongMember() const { return HasStrong; }
895 bool isAtomic() const { return IsAtomic; }
896 bool isCopy() const { return IsCopy; }
897
898 CharUnits getIvarSize() const { return IvarSize; }
899 CharUnits getIvarAlignment() const { return IvarAlignment; }
900
901 PropertyImplStrategy(CodeGenModule &CGM,
902 const ObjCPropertyImplDecl *propImpl);
903
904 private:
905 unsigned Kind : 8;
906 unsigned IsAtomic : 1;
907 unsigned IsCopy : 1;
908 unsigned HasStrong : 1;
909
910 CharUnits IvarSize;
911 CharUnits IvarAlignment;
912 };
913}
914
915/// Pick an implementation strategy for the given property synthesis.
916PropertyImplStrategy::PropertyImplStrategy(CodeGenModule &CGM,
917 const ObjCPropertyImplDecl *propImpl) {
918 const ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
919 ObjCPropertyDecl::SetterKind setterKind = prop->getSetterKind();
920
921 IsCopy = (setterKind == ObjCPropertyDecl::Copy);
922 IsAtomic = prop->isAtomic();
923 HasStrong = false; // doesn't matter here.
924
925 // Evaluate the ivar's size and alignment.
926 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
927 QualType ivarType = ivar->getType();
928 auto TInfo = CGM.getContext().getTypeInfoInChars(ivarType);
929 IvarSize = TInfo.Width;
930 IvarAlignment = TInfo.Align;
931
932 // If we have a copy property, we always have to use setProperty.
933 // If the property is atomic we need to use getProperty, but in
934 // the nonatomic case we can just use expression.
935 if (IsCopy) {
936 Kind = IsAtomic ? GetSetProperty : SetPropertyAndExpressionGet;
937 return;
938 }
939
940 // Handle retain.
941 if (setterKind == ObjCPropertyDecl::Retain) {
942 // In GC-only, there's nothing special that needs to be done.
943 if (CGM.getLangOpts().getGC() == LangOptions::GCOnly) {
944 // fallthrough
945
946 // In ARC, if the property is non-atomic, use expression emission,
947 // which translates to objc_storeStrong. This isn't required, but
948 // it's slightly nicer.
949 } else if (CGM.getLangOpts().ObjCAutoRefCount && !IsAtomic) {
950 // Using standard expression emission for the setter is only
951 // acceptable if the ivar is __strong, which won't be true if
952 // the property is annotated with __attribute__((NSObject)).
953 // TODO: falling all the way back to objc_setProperty here is
954 // just laziness, though; we could still use objc_storeStrong
955 // if we hacked it right.
956 if (ivarType.getObjCLifetime() == Qualifiers::OCL_Strong)
957 Kind = Expression;
958 else
959 Kind = SetPropertyAndExpressionGet;
960 return;
961
962 // Otherwise, we need to at least use setProperty. However, if
963 // the property isn't atomic, we can use normal expression
964 // emission for the getter.
965 } else if (!IsAtomic) {
966 Kind = SetPropertyAndExpressionGet;
967 return;
968
969 // Otherwise, we have to use both setProperty and getProperty.
970 } else {
971 Kind = GetSetProperty;
972 return;
973 }
974 }
975
976 // If we're not atomic, just use expression accesses.
977 if (!IsAtomic) {
978 Kind = Expression;
979 return;
980 }
981
982 // Properties on bitfield ivars need to be emitted using expression
983 // accesses even if they're nominally atomic.
984 if (ivar->isBitField()) {
985 Kind = Expression;
986 return;
987 }
988
989 // GC-qualified or ARC-qualified ivars need to be emitted as
990 // expressions. This actually works out to being atomic anyway,
991 // except for ARC __strong, but that should trigger the above code.
992 if (ivarType.hasNonTrivialObjCLifetime() ||
993 (CGM.getLangOpts().getGC() &&
994 CGM.getContext().getObjCGCAttrKind(ivarType))) {
995 Kind = Expression;
996 return;
997 }
998
999 // Compute whether the ivar has strong members.
1000 if (CGM.getLangOpts().getGC())
1001 if (const RecordType *recordType = ivarType->getAs<RecordType>())
1002 HasStrong = recordType->getDecl()->hasObjectMember();
1003
1004 // We can never access structs with object members with a native
1005 // access, because we need to use write barriers. This is what
1006 // objc_copyStruct is for.
1007 if (HasStrong) {
1008 Kind = CopyStruct;
1009 return;
1010 }
1011
1012 // Otherwise, this is target-dependent and based on the size and
1013 // alignment of the ivar.
1014
1015 // If the size of the ivar is not a power of two, give up. We don't
1016 // want to get into the business of doing compare-and-swaps.
1017 if (!IvarSize.isPowerOfTwo()) {
1018 Kind = CopyStruct;
1019 return;
1020 }
1021
1022 llvm::Triple::ArchType arch =
1023 CGM.getTarget().getTriple().getArch();
1024
1025 // Most architectures require memory to fit within a single cache
1026 // line, so the alignment has to be at least the size of the access.
1027 // Otherwise we have to grab a lock.
1028 if (IvarAlignment < IvarSize && !hasUnalignedAtomics(arch)) {
1029 Kind = CopyStruct;
1030 return;
1031 }
1032
1033 // If the ivar's size exceeds the architecture's maximum atomic
1034 // access size, we have to use CopyStruct.
1035 if (IvarSize > getMaxAtomicAccessSize(CGM, arch)) {
1036 Kind = CopyStruct;
1037 return;
1038 }
1039
1040 // Otherwise, we can use native loads and stores.
1041 Kind = Native;
1042}
1043
1044/// Generate an Objective-C property getter function.
1045///
1046/// The given Decl must be an ObjCImplementationDecl. \@synthesize
1047/// is illegal within a category.
1048void CodeGenFunction::GenerateObjCGetter(ObjCImplementationDecl *IMP,
1049 const ObjCPropertyImplDecl *PID) {
1050 llvm::Constant *AtomicHelperFn =
1051 CodeGenFunction(CGM).GenerateObjCAtomicGetterCopyHelperFunction(PID);
1052 ObjCMethodDecl *OMD = PID->getGetterMethodDecl();
1053 assert(OMD && "Invalid call to generate getter (empty method)")(static_cast <bool> (OMD && "Invalid call to generate getter (empty method)"
) ? void (0) : __assert_fail ("OMD && \"Invalid call to generate getter (empty method)\""
, "clang/lib/CodeGen/CGObjC.cpp", 1053, __extension__ __PRETTY_FUNCTION__
))
;
1054 StartObjCMethod(OMD, IMP->getClassInterface());
1055
1056 generateObjCGetterBody(IMP, PID, OMD, AtomicHelperFn);
1057
1058 FinishFunction(OMD->getEndLoc());
1059}
1060
1061static bool hasTrivialGetExpr(const ObjCPropertyImplDecl *propImpl) {
1062 const Expr *getter = propImpl->getGetterCXXConstructor();
1063 if (!getter) return true;
1064
1065 // Sema only makes only of these when the ivar has a C++ class type,
1066 // so the form is pretty constrained.
1067
1068 // If the property has a reference type, we might just be binding a
1069 // reference, in which case the result will be a gl-value. We should
1070 // treat this as a non-trivial operation.
1071 if (getter->isGLValue())
1072 return false;
1073
1074 // If we selected a trivial copy-constructor, we're okay.
1075 if (const CXXConstructExpr *construct = dyn_cast<CXXConstructExpr>(getter))
1076 return (construct->getConstructor()->isTrivial());
1077
1078 // The constructor might require cleanups (in which case it's never
1079 // trivial).
1080 assert(isa<ExprWithCleanups>(getter))(static_cast <bool> (isa<ExprWithCleanups>(getter
)) ? void (0) : __assert_fail ("isa<ExprWithCleanups>(getter)"
, "clang/lib/CodeGen/CGObjC.cpp", 1080, __extension__ __PRETTY_FUNCTION__
))
;
1081 return false;
1082}
1083
1084/// emitCPPObjectAtomicGetterCall - Call the runtime function to
1085/// copy the ivar into the resturn slot.
1086static void emitCPPObjectAtomicGetterCall(CodeGenFunction &CGF,
1087 llvm::Value *returnAddr,
1088 ObjCIvarDecl *ivar,
1089 llvm::Constant *AtomicHelperFn) {
1090 // objc_copyCppObjectAtomic (&returnSlot, &CppObjectIvar,
1091 // AtomicHelperFn);
1092 CallArgList args;
1093
1094 // The 1st argument is the return Slot.
1095 args.add(RValue::get(returnAddr), CGF.getContext().VoidPtrTy);
1096
1097 // The 2nd argument is the address of the ivar.
1098 llvm::Value *ivarAddr =
1099 CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), CGF.LoadObjCSelf(), ivar, 0)
1100 .getPointer(CGF);
1101 ivarAddr = CGF.Builder.CreateBitCast(ivarAddr, CGF.Int8PtrTy);
1102 args.add(RValue::get(ivarAddr), CGF.getContext().VoidPtrTy);
1103
1104 // Third argument is the helper function.
1105 args.add(RValue::get(AtomicHelperFn), CGF.getContext().VoidPtrTy);
1106
1107 llvm::FunctionCallee copyCppAtomicObjectFn =
1108 CGF.CGM.getObjCRuntime().GetCppAtomicObjectGetFunction();
1109 CGCallee callee = CGCallee::forDirect(copyCppAtomicObjectFn);
1110 CGF.EmitCall(
1111 CGF.getTypes().arrangeBuiltinFunctionCall(CGF.getContext().VoidTy, args),
1112 callee, ReturnValueSlot(), args);
1113}
1114
1115// emitCmdValueForGetterSetterBody - Handle emitting the load necessary for
1116// the `_cmd` selector argument for getter/setter bodies. For direct methods,
1117// this returns an undefined/poison value; this matches behavior prior to `_cmd`
1118// being removed from the direct method ABI as the getter/setter caller would
1119// never load one. For non-direct methods, this emits a load of the implicit
1120// `_cmd` storage.
1121static llvm::Value *emitCmdValueForGetterSetterBody(CodeGenFunction &CGF,
1122 ObjCMethodDecl *MD) {
1123 if (MD->isDirectMethod()) {
1124 // Direct methods do not have a `_cmd` argument. Emit an undefined/poison
1125 // value. This will be passed to objc_getProperty/objc_setProperty, which
1126 // has not appeared bothered by the `_cmd` argument being undefined before.
1127 llvm::Type *selType = CGF.ConvertType(CGF.getContext().getObjCSelType());
1128 return llvm::PoisonValue::get(selType);
1129 }
1130
1131 return CGF.Builder.CreateLoad(CGF.GetAddrOfLocalVar(MD->getCmdDecl()), "cmd");
1132}
1133
1134void
1135CodeGenFunction::generateObjCGetterBody(const ObjCImplementationDecl *classImpl,
1136 const ObjCPropertyImplDecl *propImpl,
1137 const ObjCMethodDecl *GetterMethodDecl,
1138 llvm::Constant *AtomicHelperFn) {
1139
1140 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
1141
1142 if (ivar->getType().isNonTrivialToPrimitiveCopy() == QualType::PCK_Struct) {
1143 if (!AtomicHelperFn) {
1144 LValue Src =
1145 EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar, 0);
1146 LValue Dst = MakeAddrLValue(ReturnValue, ivar->getType());
1147 callCStructCopyConstructor(Dst, Src);
1148 } else {
1149 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
1150 emitCPPObjectAtomicGetterCall(*this, ReturnValue.getPointer(), ivar,
1151 AtomicHelperFn);
1152 }
1153 return;
1154 }
1155
1156 // If there's a non-trivial 'get' expression, we just have to emit that.
1157 if (!hasTrivialGetExpr(propImpl)) {
1158 if (!AtomicHelperFn) {
1159 auto *ret = ReturnStmt::Create(getContext(), SourceLocation(),
1160 propImpl->getGetterCXXConstructor(),
1161 /* NRVOCandidate=*/nullptr);
1162 EmitReturnStmt(*ret);
1163 }
1164 else {
1165 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
1166 emitCPPObjectAtomicGetterCall(*this, ReturnValue.getPointer(),
1167 ivar, AtomicHelperFn);
1168 }
1169 return;
1170 }
1171
1172 const ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
1173 QualType propType = prop->getType();
1174 ObjCMethodDecl *getterMethod = propImpl->getGetterMethodDecl();
1175
1176 // Pick an implementation strategy.
1177 PropertyImplStrategy strategy(CGM, propImpl);
1178 switch (strategy.getKind()) {
1179 case PropertyImplStrategy::Native: {
1180 // We don't need to do anything for a zero-size struct.
1181 if (strategy.getIvarSize().isZero())
1182 return;
1183
1184 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar, 0);
1185
1186 // Currently, all atomic accesses have to be through integer
1187 // types, so there's no point in trying to pick a prettier type.
1188 uint64_t ivarSize = getContext().toBits(strategy.getIvarSize());
1189 llvm::Type *bitcastType = llvm::Type::getIntNTy(getLLVMContext(), ivarSize);
1190
1191 // Perform an atomic load. This does not impose ordering constraints.
1192 Address ivarAddr = LV.getAddress(*this);
1193 ivarAddr = Builder.CreateElementBitCast(ivarAddr, bitcastType);
1194 llvm::LoadInst *load = Builder.CreateLoad(ivarAddr, "load");
1195 load->setAtomic(llvm::AtomicOrdering::Unordered);
1196
1197 // Store that value into the return address. Doing this with a
1198 // bitcast is likely to produce some pretty ugly IR, but it's not
1199 // the *most* terrible thing in the world.
1200 llvm::Type *retTy = ConvertType(getterMethod->getReturnType());
1201 uint64_t retTySize = CGM.getDataLayout().getTypeSizeInBits(retTy);
1202 llvm::Value *ivarVal = load;
1203 if (ivarSize > retTySize) {
1204 bitcastType = llvm::Type::getIntNTy(getLLVMContext(), retTySize);
1205 ivarVal = Builder.CreateTrunc(load, bitcastType);
1206 }
1207 Builder.CreateStore(ivarVal,
1208 Builder.CreateElementBitCast(ReturnValue, bitcastType));
1209
1210 // Make sure we don't do an autorelease.
1211 AutoreleaseResult = false;
1212 return;
1213 }
1214
1215 case PropertyImplStrategy::GetSetProperty: {
1216 llvm::FunctionCallee getPropertyFn =
1217 CGM.getObjCRuntime().GetPropertyGetFunction();
1218 if (!getPropertyFn) {
1219 CGM.ErrorUnsupported(propImpl, "Obj-C getter requiring atomic copy");
1220 return;
1221 }
1222 CGCallee callee = CGCallee::forDirect(getPropertyFn);
1223
1224 // Return (ivar-type) objc_getProperty((id) self, _cmd, offset, true).
1225 // FIXME: Can't this be simpler? This might even be worse than the
1226 // corresponding gcc code.
1227 llvm::Value *cmd = emitCmdValueForGetterSetterBody(*this, getterMethod);
1228 llvm::Value *self = Builder.CreateBitCast(LoadObjCSelf(), VoidPtrTy);
1229 llvm::Value *ivarOffset =
1230 EmitIvarOffsetAsPointerDiff(classImpl->getClassInterface(), ivar);
1231
1232 CallArgList args;
1233 args.add(RValue::get(self), getContext().getObjCIdType());
1234 args.add(RValue::get(cmd), getContext().getObjCSelType());
1235 args.add(RValue::get(ivarOffset), getContext().getPointerDiffType());
1236 args.add(RValue::get(Builder.getInt1(strategy.isAtomic())),
1237 getContext().BoolTy);
1238
1239 // FIXME: We shouldn't need to get the function info here, the
1240 // runtime already should have computed it to build the function.
1241 llvm::CallBase *CallInstruction;
1242 RValue RV = EmitCall(getTypes().arrangeBuiltinFunctionCall(
1243 getContext().getObjCIdType(), args),
1244 callee, ReturnValueSlot(), args, &CallInstruction);
1245 if (llvm::CallInst *call = dyn_cast<llvm::CallInst>(CallInstruction))
1246 call->setTailCall();
1247
1248 // We need to fix the type here. Ivars with copy & retain are
1249 // always objects so we don't need to worry about complex or
1250 // aggregates.
1251 RV = RValue::get(Builder.CreateBitCast(
1252 RV.getScalarVal(),
1253 getTypes().ConvertType(getterMethod->getReturnType())));
1254
1255 EmitReturnOfRValue(RV, propType);
1256
1257 // objc_getProperty does an autorelease, so we should suppress ours.
1258 AutoreleaseResult = false;
1259
1260 return;
1261 }
1262
1263 case PropertyImplStrategy::CopyStruct:
1264 emitStructGetterCall(*this, ivar, strategy.isAtomic(),
1265 strategy.hasStrongMember());
1266 return;
1267
1268 case PropertyImplStrategy::Expression:
1269 case PropertyImplStrategy::SetPropertyAndExpressionGet: {
1270 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar, 0);
1271
1272 QualType ivarType = ivar->getType();
1273 switch (getEvaluationKind(ivarType)) {
1274 case TEK_Complex: {
1275 ComplexPairTy pair = EmitLoadOfComplex(LV, SourceLocation());
1276 EmitStoreOfComplex(pair, MakeAddrLValue(ReturnValue, ivarType),
1277 /*init*/ true);
1278 return;
1279 }
1280 case TEK_Aggregate: {
1281 // The return value slot is guaranteed to not be aliased, but
1282 // that's not necessarily the same as "on the stack", so
1283 // we still potentially need objc_memmove_collectable.
1284 EmitAggregateCopy(/* Dest= */ MakeAddrLValue(ReturnValue, ivarType),
1285 /* Src= */ LV, ivarType, getOverlapForReturnValue());
1286 return;
1287 }
1288 case TEK_Scalar: {
1289 llvm::Value *value;
1290 if (propType->isReferenceType()) {
1291 value = LV.getAddress(*this).getPointer();
1292 } else {
1293 // We want to load and autoreleaseReturnValue ARC __weak ivars.
1294 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
1295 if (getLangOpts().ObjCAutoRefCount) {
1296 value = emitARCRetainLoadOfScalar(*this, LV, ivarType);
1297 } else {
1298 value = EmitARCLoadWeak(LV.getAddress(*this));
1299 }
1300
1301 // Otherwise we want to do a simple load, suppressing the
1302 // final autorelease.
1303 } else {
1304 value = EmitLoadOfLValue(LV, SourceLocation()).getScalarVal();
1305 AutoreleaseResult = false;
1306 }
1307
1308 value = Builder.CreateBitCast(
1309 value, ConvertType(GetterMethodDecl->getReturnType()));
1310 }
1311
1312 EmitReturnOfRValue(RValue::get(value), propType);
1313 return;
1314 }
1315 }
1316 llvm_unreachable("bad evaluation kind")::llvm::llvm_unreachable_internal("bad evaluation kind", "clang/lib/CodeGen/CGObjC.cpp"
, 1316)
;
1317 }
1318
1319 }
1320 llvm_unreachable("bad @property implementation strategy!")::llvm::llvm_unreachable_internal("bad @property implementation strategy!"
, "clang/lib/CodeGen/CGObjC.cpp", 1320)
;
1321}
1322
1323/// emitStructSetterCall - Call the runtime function to store the value
1324/// from the first formal parameter into the given ivar.
1325static void emitStructSetterCall(CodeGenFunction &CGF, ObjCMethodDecl *OMD,
1326 ObjCIvarDecl *ivar) {
1327 // objc_copyStruct (&structIvar, &Arg,
1328 // sizeof (struct something), true, false);
1329 CallArgList args;
1330
1331 // The first argument is the address of the ivar.
1332 llvm::Value *ivarAddr =
1333 CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), CGF.LoadObjCSelf(), ivar, 0)
1334 .getPointer(CGF);
1335 ivarAddr = CGF.Builder.CreateBitCast(ivarAddr, CGF.Int8PtrTy);
1336 args.add(RValue::get(ivarAddr), CGF.getContext().VoidPtrTy);
1337
1338 // The second argument is the address of the parameter variable.
1339 ParmVarDecl *argVar = *OMD->param_begin();
1340 DeclRefExpr argRef(CGF.getContext(), argVar, false,
1341 argVar->getType().getNonReferenceType(), VK_LValue,
1342 SourceLocation());
1343 llvm::Value *argAddr = CGF.EmitLValue(&argRef).getPointer(CGF);
1344 argAddr = CGF.Builder.CreateBitCast(argAddr, CGF.Int8PtrTy);
1345 args.add(RValue::get(argAddr), CGF.getContext().VoidPtrTy);
1346
1347 // The third argument is the sizeof the type.
1348 llvm::Value *size =
1349 CGF.CGM.getSize(CGF.getContext().getTypeSizeInChars(ivar->getType()));
1350 args.add(RValue::get(size), CGF.getContext().getSizeType());
1351
1352 // The fourth argument is the 'isAtomic' flag.
1353 args.add(RValue::get(CGF.Builder.getTrue()), CGF.getContext().BoolTy);
1354
1355 // The fifth argument is the 'hasStrong' flag.
1356 // FIXME: should this really always be false?
1357 args.add(RValue::get(CGF.Builder.getFalse()), CGF.getContext().BoolTy);
1358
1359 llvm::FunctionCallee fn = CGF.CGM.getObjCRuntime().GetSetStructFunction();
1360 CGCallee callee = CGCallee::forDirect(fn);
1361 CGF.EmitCall(
1362 CGF.getTypes().arrangeBuiltinFunctionCall(CGF.getContext().VoidTy, args),
1363 callee, ReturnValueSlot(), args);
1364}
1365
1366/// emitCPPObjectAtomicSetterCall - Call the runtime function to store
1367/// the value from the first formal parameter into the given ivar, using
1368/// the Cpp API for atomic Cpp objects with non-trivial copy assignment.
1369static void emitCPPObjectAtomicSetterCall(CodeGenFunction &CGF,
1370 ObjCMethodDecl *OMD,
1371 ObjCIvarDecl *ivar,
1372 llvm::Constant *AtomicHelperFn) {
1373 // objc_copyCppObjectAtomic (&CppObjectIvar, &Arg,
1374 // AtomicHelperFn);
1375 CallArgList args;
1376
1377 // The first argument is the address of the ivar.
1378 llvm::Value *ivarAddr =
1379 CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), CGF.LoadObjCSelf(), ivar, 0)
1380 .getPointer(CGF);
1381 ivarAddr = CGF.Builder.CreateBitCast(ivarAddr, CGF.Int8PtrTy);
1382 args.add(RValue::get(ivarAddr), CGF.getContext().VoidPtrTy);
1383
1384 // The second argument is the address of the parameter variable.
1385 ParmVarDecl *argVar = *OMD->param_begin();
1386 DeclRefExpr argRef(CGF.getContext(), argVar, false,
1387 argVar->getType().getNonReferenceType(), VK_LValue,
1388 SourceLocation());
1389 llvm::Value *argAddr = CGF.EmitLValue(&argRef).getPointer(CGF);
1390 argAddr = CGF.Builder.CreateBitCast(argAddr, CGF.Int8PtrTy);
1391 args.add(RValue::get(argAddr), CGF.getContext().VoidPtrTy);
1392
1393 // Third argument is the helper function.
1394 args.add(RValue::get(AtomicHelperFn), CGF.getContext().VoidPtrTy);
1395
1396 llvm::FunctionCallee fn =
1397 CGF.CGM.getObjCRuntime().GetCppAtomicObjectSetFunction();
1398 CGCallee callee = CGCallee::forDirect(fn);
1399 CGF.EmitCall(
1400 CGF.getTypes().arrangeBuiltinFunctionCall(CGF.getContext().VoidTy, args),
1401 callee, ReturnValueSlot(), args);
1402}
1403
1404
1405static bool hasTrivialSetExpr(const ObjCPropertyImplDecl *PID) {
1406 Expr *setter = PID->getSetterCXXAssignment();
1407 if (!setter) return true;
1408
1409 // Sema only makes only of these when the ivar has a C++ class type,
1410 // so the form is pretty constrained.
1411
1412 // An operator call is trivial if the function it calls is trivial.
1413 // This also implies that there's nothing non-trivial going on with
1414 // the arguments, because operator= can only be trivial if it's a
1415 // synthesized assignment operator and therefore both parameters are
1416 // references.
1417 if (CallExpr *call = dyn_cast<CallExpr>(setter)) {
1418 if (const FunctionDecl *callee
1419 = dyn_cast_or_null<FunctionDecl>(call->getCalleeDecl()))
1420 if (callee->isTrivial())
1421 return true;
1422 return false;
1423 }
1424
1425 assert(isa<ExprWithCleanups>(setter))(static_cast <bool> (isa<ExprWithCleanups>(setter
)) ? void (0) : __assert_fail ("isa<ExprWithCleanups>(setter)"
, "clang/lib/CodeGen/CGObjC.cpp", 1425, __extension__ __PRETTY_FUNCTION__
))
;
1426 return false;
1427}
1428
1429static bool UseOptimizedSetter(CodeGenModule &CGM) {
1430 if (CGM.getLangOpts().getGC() != LangOptions::NonGC)
1431 return false;
1432 return CGM.getLangOpts().ObjCRuntime.hasOptimizedSetter();
1433}
1434
1435void
1436CodeGenFunction::generateObjCSetterBody(const ObjCImplementationDecl *classImpl,
1437 const ObjCPropertyImplDecl *propImpl,
1438 llvm::Constant *AtomicHelperFn) {
1439 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
1440 ObjCMethodDecl *setterMethod = propImpl->getSetterMethodDecl();
1441
1442 if (ivar->getType().isNonTrivialToPrimitiveCopy() == QualType::PCK_Struct) {
1443 ParmVarDecl *PVD = *setterMethod->param_begin();
1444 if (!AtomicHelperFn) {
1445 // Call the move assignment operator instead of calling the copy
1446 // assignment operator and destructor.
1447 LValue Dst = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar,
1448 /*quals*/ 0);
1449 LValue Src = MakeAddrLValue(GetAddrOfLocalVar(PVD), ivar->getType());
1450 callCStructMoveAssignmentOperator(Dst, Src);
1451 } else {
1452 // If atomic, assignment is called via a locking api.
1453 emitCPPObjectAtomicSetterCall(*this, setterMethod, ivar, AtomicHelperFn);
1454 }
1455 // Decativate the destructor for the setter parameter.
1456 DeactivateCleanupBlock(CalleeDestructedParamCleanups[PVD], AllocaInsertPt);
1457 return;
1458 }
1459
1460 // Just use the setter expression if Sema gave us one and it's
1461 // non-trivial.
1462 if (!hasTrivialSetExpr(propImpl)) {
1463 if (!AtomicHelperFn)
1464 // If non-atomic, assignment is called directly.
1465 EmitStmt(propImpl->getSetterCXXAssignment());
1466 else
1467 // If atomic, assignment is called via a locking api.
1468 emitCPPObjectAtomicSetterCall(*this, setterMethod, ivar,
1469 AtomicHelperFn);
1470 return;
1471 }
1472
1473 PropertyImplStrategy strategy(CGM, propImpl);
1474 switch (strategy.getKind()) {
1475 case PropertyImplStrategy::Native: {
1476 // We don't need to do anything for a zero-size struct.
1477 if (strategy.getIvarSize().isZero())
1478 return;
1479
1480 Address argAddr = GetAddrOfLocalVar(*setterMethod->param_begin());
1481
1482 LValue ivarLValue =
1483 EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar, /*quals*/ 0);
1484 Address ivarAddr = ivarLValue.getAddress(*this);
1485
1486 // Currently, all atomic accesses have to be through integer
1487 // types, so there's no point in trying to pick a prettier type.
1488 llvm::Type *bitcastType =
1489 llvm::Type::getIntNTy(getLLVMContext(),
1490 getContext().toBits(strategy.getIvarSize()));
1491
1492 // Cast both arguments to the chosen operation type.
1493 argAddr = Builder.CreateElementBitCast(argAddr, bitcastType);
1494 ivarAddr = Builder.CreateElementBitCast(ivarAddr, bitcastType);
1495
1496 // This bitcast load is likely to cause some nasty IR.
1497 llvm::Value *load = Builder.CreateLoad(argAddr);
1498
1499 // Perform an atomic store. There are no memory ordering requirements.
1500 llvm::StoreInst *store = Builder.CreateStore(load, ivarAddr);
1501 store->setAtomic(llvm::AtomicOrdering::Unordered);
1502 return;
1503 }
1504
1505 case PropertyImplStrategy::GetSetProperty:
1506 case PropertyImplStrategy::SetPropertyAndExpressionGet: {
1507
1508 llvm::FunctionCallee setOptimizedPropertyFn = nullptr;
1509 llvm::FunctionCallee setPropertyFn = nullptr;
1510 if (UseOptimizedSetter(CGM)) {
1511 // 10.8 and iOS 6.0 code and GC is off
1512 setOptimizedPropertyFn =
1513 CGM.getObjCRuntime().GetOptimizedPropertySetFunction(
1514 strategy.isAtomic(), strategy.isCopy());
1515 if (!setOptimizedPropertyFn) {
1516 CGM.ErrorUnsupported(propImpl, "Obj-C optimized setter - NYI");
1517 return;
1518 }
1519 }
1520 else {
1521 setPropertyFn = CGM.getObjCRuntime().GetPropertySetFunction();
1522 if (!setPropertyFn) {
1523 CGM.ErrorUnsupported(propImpl, "Obj-C setter requiring atomic copy");
1524 return;
1525 }
1526 }
1527
1528 // Emit objc_setProperty((id) self, _cmd, offset, arg,
1529 // <is-atomic>, <is-copy>).
1530 llvm::Value *cmd = emitCmdValueForGetterSetterBody(*this, setterMethod);
1531 llvm::Value *self =
1532 Builder.CreateBitCast(LoadObjCSelf(), VoidPtrTy);
1533 llvm::Value *ivarOffset =
1534 EmitIvarOffsetAsPointerDiff(classImpl->getClassInterface(), ivar);
1535 Address argAddr = GetAddrOfLocalVar(*setterMethod->param_begin());
1536 llvm::Value *arg = Builder.CreateLoad(argAddr, "arg");
1537 arg = Builder.CreateBitCast(arg, VoidPtrTy);
1538
1539 CallArgList args;
1540 args.add(RValue::get(self), getContext().getObjCIdType());
1541 args.add(RValue::get(cmd), getContext().getObjCSelType());
1542 if (setOptimizedPropertyFn) {
1543 args.add(RValue::get(arg), getContext().getObjCIdType());
1544 args.add(RValue::get(ivarOffset), getContext().getPointerDiffType());
1545 CGCallee callee = CGCallee::forDirect(setOptimizedPropertyFn);
1546 EmitCall(getTypes().arrangeBuiltinFunctionCall(getContext().VoidTy, args),
1547 callee, ReturnValueSlot(), args);
1548 } else {
1549 args.add(RValue::get(ivarOffset), getContext().getPointerDiffType());
1550 args.add(RValue::get(arg), getContext().getObjCIdType());
1551 args.add(RValue::get(Builder.getInt1(strategy.isAtomic())),
1552 getContext().BoolTy);
1553 args.add(RValue::get(Builder.getInt1(strategy.isCopy())),
1554 getContext().BoolTy);
1555 // FIXME: We shouldn't need to get the function info here, the runtime
1556 // already should have computed it to build the function.
1557 CGCallee callee = CGCallee::forDirect(setPropertyFn);
1558 EmitCall(getTypes().arrangeBuiltinFunctionCall(getContext().VoidTy, args),
1559 callee, ReturnValueSlot(), args);
1560 }
1561
1562 return;
1563 }
1564
1565 case PropertyImplStrategy::CopyStruct:
1566 emitStructSetterCall(*this, setterMethod, ivar);
1567 return;
1568
1569 case PropertyImplStrategy::Expression:
1570 break;
1571 }
1572
1573 // Otherwise, fake up some ASTs and emit a normal assignment.
1574 ValueDecl *selfDecl = setterMethod->getSelfDecl();
1575 DeclRefExpr self(getContext(), selfDecl, false, selfDecl->getType(),
1576 VK_LValue, SourceLocation());
1577 ImplicitCastExpr selfLoad(ImplicitCastExpr::OnStack, selfDecl->getType(),
1578 CK_LValueToRValue, &self, VK_PRValue,
1579 FPOptionsOverride());
1580 ObjCIvarRefExpr ivarRef(ivar, ivar->getType().getNonReferenceType(),
1581 SourceLocation(), SourceLocation(),
1582 &selfLoad, true, true);
1583
1584 ParmVarDecl *argDecl = *setterMethod->param_begin();
1585 QualType argType = argDecl->getType().getNonReferenceType();
1586 DeclRefExpr arg(getContext(), argDecl, false, argType, VK_LValue,
1587 SourceLocation());
1588 ImplicitCastExpr argLoad(ImplicitCastExpr::OnStack,
1589 argType.getUnqualifiedType(), CK_LValueToRValue,
1590 &arg, VK_PRValue, FPOptionsOverride());
1591
1592 // The property type can differ from the ivar type in some situations with
1593 // Objective-C pointer types, we can always bit cast the RHS in these cases.
1594 // The following absurdity is just to ensure well-formed IR.
1595 CastKind argCK = CK_NoOp;
1596 if (ivarRef.getType()->isObjCObjectPointerType()) {
1597 if (argLoad.getType()->isObjCObjectPointerType())
1598 argCK = CK_BitCast;
1599 else if (argLoad.getType()->isBlockPointerType())
1600 argCK = CK_BlockPointerToObjCPointerCast;
1601 else
1602 argCK = CK_CPointerToObjCPointerCast;
1603 } else if (ivarRef.getType()->isBlockPointerType()) {
1604 if (argLoad.getType()->isBlockPointerType())
1605 argCK = CK_BitCast;
1606 else
1607 argCK = CK_AnyPointerToBlockPointerCast;
1608 } else if (ivarRef.getType()->isPointerType()) {
1609 argCK = CK_BitCast;
1610 } else if (argLoad.getType()->isAtomicType() &&
1611 !ivarRef.getType()->isAtomicType()) {
1612 argCK = CK_AtomicToNonAtomic;
1613 } else if (!argLoad.getType()->isAtomicType() &&
1614 ivarRef.getType()->isAtomicType()) {
1615 argCK = CK_NonAtomicToAtomic;
1616 }
1617 ImplicitCastExpr argCast(ImplicitCastExpr::OnStack, ivarRef.getType(), argCK,
1618 &argLoad, VK_PRValue, FPOptionsOverride());
1619 Expr *finalArg = &argLoad;
1620 if (!getContext().hasSameUnqualifiedType(ivarRef.getType(),
1621 argLoad.getType()))
1622 finalArg = &argCast;
1623
1624 BinaryOperator *assign = BinaryOperator::Create(
1625 getContext(), &ivarRef, finalArg, BO_Assign, ivarRef.getType(),
1626 VK_PRValue, OK_Ordinary, SourceLocation(), FPOptionsOverride());
1627 EmitStmt(assign);
1628}
1629
1630/// Generate an Objective-C property setter function.
1631///
1632/// The given Decl must be an ObjCImplementationDecl. \@synthesize
1633/// is illegal within a category.
1634void CodeGenFunction::GenerateObjCSetter(ObjCImplementationDecl *IMP,
1635 const ObjCPropertyImplDecl *PID) {
1636 llvm::Constant *AtomicHelperFn =
1637 CodeGenFunction(CGM).GenerateObjCAtomicSetterCopyHelperFunction(PID);
1638 ObjCMethodDecl *OMD = PID->getSetterMethodDecl();
1639 assert(OMD && "Invalid call to generate setter (empty method)")(static_cast <bool> (OMD && "Invalid call to generate setter (empty method)"
) ? void (0) : __assert_fail ("OMD && \"Invalid call to generate setter (empty method)\""
, "clang/lib/CodeGen/CGObjC.cpp", 1639, __extension__ __PRETTY_FUNCTION__
))
;
1640 StartObjCMethod(OMD, IMP->getClassInterface());
1641
1642 generateObjCSetterBody(IMP, PID, AtomicHelperFn);
1643
1644 FinishFunction(OMD->getEndLoc());
1645}
1646
1647namespace {
1648 struct DestroyIvar final : EHScopeStack::Cleanup {
1649 private:
1650 llvm::Value *addr;
1651 const ObjCIvarDecl *ivar;
1652 CodeGenFunction::Destroyer *destroyer;
1653 bool useEHCleanupForArray;
1654 public:
1655 DestroyIvar(llvm::Value *addr, const ObjCIvarDecl *ivar,
1656 CodeGenFunction::Destroyer *destroyer,
1657 bool useEHCleanupForArray)
1658 : addr(addr), ivar(ivar), destroyer(destroyer),
1659 useEHCleanupForArray(useEHCleanupForArray) {}
1660
1661 void Emit(CodeGenFunction &CGF, Flags flags) override {
1662 LValue lvalue
1663 = CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), addr, ivar, /*CVR*/ 0);
1664 CGF.emitDestroy(lvalue.getAddress(CGF), ivar->getType(), destroyer,
1665 flags.isForNormalCleanup() && useEHCleanupForArray);
1666 }
1667 };
1668}
1669
1670/// Like CodeGenFunction::destroyARCStrong, but do it with a call.
1671static void destroyARCStrongWithStore(CodeGenFunction &CGF,
1672 Address addr,
1673 QualType type) {
1674 llvm::Value *null = getNullForVariable(addr);
1675 CGF.EmitARCStoreStrongCall(addr, null, /*ignored*/ true);
1676}
1677
1678static void emitCXXDestructMethod(CodeGenFunction &CGF,
1679 ObjCImplementationDecl *impl) {
1680 CodeGenFunction::RunCleanupsScope scope(CGF);
1681
1682 llvm::Value *self = CGF.LoadObjCSelf();
1683
1684 const ObjCInterfaceDecl *iface = impl->getClassInterface();
1685 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
1686 ivar; ivar = ivar->getNextIvar()) {
1687 QualType type = ivar->getType();
1688
1689 // Check whether the ivar is a destructible type.
1690 QualType::DestructionKind dtorKind = type.isDestructedType();
1691 if (!dtorKind) continue;
1692
1693 CodeGenFunction::Destroyer *destroyer = nullptr;
1694
1695 // Use a call to objc_storeStrong to destroy strong ivars, for the
1696 // general benefit of the tools.
1697 if (dtorKind == QualType::DK_objc_strong_lifetime) {
1698 destroyer = destroyARCStrongWithStore;
1699
1700 // Otherwise use the default for the destruction kind.
1701 } else {
1702 destroyer = CGF.getDestroyer(dtorKind);
1703 }
1704
1705 CleanupKind cleanupKind = CGF.getCleanupKind(dtorKind);
1706
1707 CGF.EHStack.pushCleanup<DestroyIvar>(cleanupKind, self, ivar, destroyer,
1708 cleanupKind & EHCleanup);
1709 }
1710
1711 assert(scope.requiresCleanups() && "nothing to do in .cxx_destruct?")(static_cast <bool> (scope.requiresCleanups() &&
"nothing to do in .cxx_destruct?") ? void (0) : __assert_fail
("scope.requiresCleanups() && \"nothing to do in .cxx_destruct?\""
, "clang/lib/CodeGen/CGObjC.cpp", 1711, __extension__ __PRETTY_FUNCTION__
))
;
1712}
1713
1714void CodeGenFunction::GenerateObjCCtorDtorMethod(ObjCImplementationDecl *IMP,
1715 ObjCMethodDecl *MD,
1716 bool ctor) {
1717 MD->createImplicitParams(CGM.getContext(), IMP->getClassInterface());
1718 StartObjCMethod(MD, IMP->getClassInterface());
1719
1720 // Emit .cxx_construct.
1721 if (ctor) {
1722 // Suppress the final autorelease in ARC.
1723 AutoreleaseResult = false;
1724
1725 for (const auto *IvarInit : IMP->inits()) {
1726 FieldDecl *Field = IvarInit->getAnyMember();
1727 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(Field);
1728 LValue LV = EmitLValueForIvar(TypeOfSelfObject(),
1729 LoadObjCSelf(), Ivar, 0);
1730 EmitAggExpr(IvarInit->getInit(),
1731 AggValueSlot::forLValue(LV, *this, AggValueSlot::IsDestructed,
1732 AggValueSlot::DoesNotNeedGCBarriers,
1733 AggValueSlot::IsNotAliased,
1734 AggValueSlot::DoesNotOverlap));
1735 }
1736 // constructor returns 'self'.
1737 CodeGenTypes &Types = CGM.getTypes();
1738 QualType IdTy(CGM.getContext().getObjCIdType());
1739 llvm::Value *SelfAsId =
1740 Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy));
1741 EmitReturnOfRValue(RValue::get(SelfAsId), IdTy);
1742
1743 // Emit .cxx_destruct.
1744 } else {
1745 emitCXXDestructMethod(*this, IMP);
1746 }
1747 FinishFunction();
1748}
1749
1750llvm::Value *CodeGenFunction::LoadObjCSelf() {
1751 VarDecl *Self = cast<ObjCMethodDecl>(CurFuncDecl)->getSelfDecl();
1752 DeclRefExpr DRE(getContext(), Self,
1753 /*is enclosing local*/ (CurFuncDecl != CurCodeDecl),
1754 Self->getType(), VK_LValue, SourceLocation());
1755 return EmitLoadOfScalar(EmitDeclRefLValue(&DRE), SourceLocation());
1756}
1757
1758QualType CodeGenFunction::TypeOfSelfObject() {
1759 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
1760 ImplicitParamDecl *selfDecl = OMD->getSelfDecl();
1761 const ObjCObjectPointerType *PTy = cast<ObjCObjectPointerType>(
1762 getContext().getCanonicalType(selfDecl->getType()));
1763 return PTy->getPointeeType();
1764}
1765
1766void CodeGenFunction::EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S){
1767 llvm::FunctionCallee EnumerationMutationFnPtr =
1768 CGM.getObjCRuntime().EnumerationMutationFunction();
1769 if (!EnumerationMutationFnPtr) {
1770 CGM.ErrorUnsupported(&S, "Obj-C fast enumeration for this runtime");
1771 return;
1772 }
1773 CGCallee EnumerationMutationFn =
1774 CGCallee::forDirect(EnumerationMutationFnPtr);
1775
1776 CGDebugInfo *DI = getDebugInfo();
1777 if (DI)
1778 DI->EmitLexicalBlockStart(Builder, S.getSourceRange().getBegin());
1779
1780 RunCleanupsScope ForScope(*this);
1781
1782 // The local variable comes into scope immediately.
1783 AutoVarEmission variable = AutoVarEmission::invalid();
1784 if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement()))
1785 variable = EmitAutoVarAlloca(*cast<VarDecl>(SD->getSingleDecl()));
1786
1787 JumpDest LoopEnd = getJumpDestInCurrentScope("forcoll.end");
1788
1789 // Fast enumeration state.
1790 QualType StateTy = CGM.getObjCFastEnumerationStateType();
1791 Address StatePtr = CreateMemTemp(StateTy, "state.ptr");
1792 EmitNullInitialization(StatePtr, StateTy);
1793
1794 // Number of elements in the items array.
1795 static const unsigned NumItems = 16;
1796
1797 // Fetch the countByEnumeratingWithState:objects:count: selector.
1798 IdentifierInfo *II[] = {
1799 &CGM.getContext().Idents.get("countByEnumeratingWithState"),
1800 &CGM.getContext().Idents.get("objects"),
1801 &CGM.getContext().Idents.get("count")
1802 };
1803 Selector FastEnumSel =
1804 CGM.getContext().Selectors.getSelector(std::size(II), &II[0]);
1805
1806 QualType ItemsTy =
1807 getContext().getConstantArrayType(getContext().getObjCIdType(),
1808 llvm::APInt(32, NumItems), nullptr,
1809 ArrayType::Normal, 0);
1810 Address ItemsPtr = CreateMemTemp(ItemsTy, "items.ptr");
1811
1812 // Emit the collection pointer. In ARC, we do a retain.
1813 llvm::Value *Collection;
1814 if (getLangOpts().ObjCAutoRefCount) {
1815 Collection = EmitARCRetainScalarExpr(S.getCollection());
1816
1817 // Enter a cleanup to do the release.
1818 EmitObjCConsumeObject(S.getCollection()->getType(), Collection);
1819 } else {
1820 Collection = EmitScalarExpr(S.getCollection());
1821 }
1822
1823 // The 'continue' label needs to appear within the cleanup for the
1824 // collection object.
1825 JumpDest AfterBody = getJumpDestInCurrentScope("forcoll.next");
1826
1827 // Send it our message:
1828 CallArgList Args;
1829
1830 // The first argument is a temporary of the enumeration-state type.
1831 Args.add(RValue::get(StatePtr.getPointer()),
1832 getContext().getPointerType(StateTy));
1833
1834 // The second argument is a temporary array with space for NumItems
1835 // pointers. We'll actually be loading elements from the array
1836 // pointer written into the control state; this buffer is so that
1837 // collections that *aren't* backed by arrays can still queue up
1838 // batches of elements.
1839 Args.add(RValue::get(ItemsPtr.getPointer()),
1840 getContext().getPointerType(ItemsTy));
1841
1842 // The third argument is the capacity of that temporary array.
1843 llvm::Type *NSUIntegerTy = ConvertType(getContext().getNSUIntegerType());
1844 llvm::Constant *Count = llvm::ConstantInt::get(NSUIntegerTy, NumItems);
1845 Args.add(RValue::get(Count), getContext().getNSUIntegerType());
1846
1847 // Start the enumeration.
1848 RValue CountRV =
1849 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
1850 getContext().getNSUIntegerType(),
1851 FastEnumSel, Collection, Args);
1852
1853 // The initial number of objects that were returned in the buffer.
1854 llvm::Value *initialBufferLimit = CountRV.getScalarVal();
1855
1856 llvm::BasicBlock *EmptyBB = createBasicBlock("forcoll.empty");
1857 llvm::BasicBlock *LoopInitBB = createBasicBlock("forcoll.loopinit");
1858
1859 llvm::Value *zero = llvm::Constant::getNullValue(NSUIntegerTy);
1860
1861 // If the limit pointer was zero to begin with, the collection is
1862 // empty; skip all this. Set the branch weight assuming this has the same
1863 // probability of exiting the loop as any other loop exit.
1864 uint64_t EntryCount = getCurrentProfileCount();
1865 Builder.CreateCondBr(
1866 Builder.CreateICmpEQ(initialBufferLimit, zero, "iszero"), EmptyBB,
1867 LoopInitBB,
1868 createProfileWeights(EntryCount, getProfileCount(S.getBody())));
1869
1870 // Otherwise, initialize the loop.
1871 EmitBlock(LoopInitBB);
1872
1873 // Save the initial mutations value. This is the value at an
1874 // address that was written into the state object by
1875 // countByEnumeratingWithState:objects:count:.
1876 Address StateMutationsPtrPtr =
1877 Builder.CreateStructGEP(StatePtr, 2, "mutationsptr.ptr");
1878 llvm::Value *StateMutationsPtr
1879 = Builder.CreateLoad(StateMutationsPtrPtr, "mutationsptr");
1880
1881 llvm::Type *UnsignedLongTy = ConvertType(getContext().UnsignedLongTy);
1882 llvm::Value *initialMutations =
1883 Builder.CreateAlignedLoad(UnsignedLongTy, StateMutationsPtr,
1884 getPointerAlign(), "forcoll.initial-mutations");
1885
1886 // Start looping. This is the point we return to whenever we have a
1887 // fresh, non-empty batch of objects.
1888 llvm::BasicBlock *LoopBodyBB = createBasicBlock("forcoll.loopbody");
1889 EmitBlock(LoopBodyBB);
1890
1891 // The current index into the buffer.
1892 llvm::PHINode *index = Builder.CreatePHI(NSUIntegerTy, 3, "forcoll.index");
1893 index->addIncoming(zero, LoopInitBB);
1894
1895 // The current buffer size.
1896 llvm::PHINode *count = Builder.CreatePHI(NSUIntegerTy, 3, "forcoll.count");
1897 count->addIncoming(initialBufferLimit, LoopInitBB);
1898
1899 incrementProfileCounter(&S);
1900
1901 // Check whether the mutations value has changed from where it was
1902 // at start. StateMutationsPtr should actually be invariant between
1903 // refreshes.
1904 StateMutationsPtr = Builder.CreateLoad(StateMutationsPtrPtr, "mutationsptr");
1905 llvm::Value *currentMutations
1906 = Builder.CreateAlignedLoad(UnsignedLongTy, StateMutationsPtr,
1907 getPointerAlign(), "statemutations");
1908
1909 llvm::BasicBlock *WasMutatedBB = createBasicBlock("forcoll.mutated");
1910 llvm::BasicBlock *WasNotMutatedBB = createBasicBlock("forcoll.notmutated");
1911
1912 Builder.CreateCondBr(Builder.CreateICmpEQ(currentMutations, initialMutations),
1913 WasNotMutatedBB, WasMutatedBB);
1914
1915 // If so, call the enumeration-mutation function.
1916 EmitBlock(WasMutatedBB);
1917 llvm::Type *ObjCIdType = ConvertType(getContext().getObjCIdType());
1918 llvm::Value *V =
1919 Builder.CreateBitCast(Collection, ObjCIdType);
1920 CallArgList Args2;
1921 Args2.add(RValue::get(V), getContext().getObjCIdType());
1922 // FIXME: We shouldn't need to get the function info here, the runtime already
1923 // should have computed it to build the function.
1924 EmitCall(
1925 CGM.getTypes().arrangeBuiltinFunctionCall(getContext().VoidTy, Args2),
1926 EnumerationMutationFn, ReturnValueSlot(), Args2);
1927
1928 // Otherwise, or if the mutation function returns, just continue.
1929 EmitBlock(WasNotMutatedBB);
1930
1931 // Initialize the element variable.
1932 RunCleanupsScope elementVariableScope(*this);
1933 bool elementIsVariable;
1934 LValue elementLValue;
1935 QualType elementType;
1936 if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement())) {
1937 // Initialize the variable, in case it's a __block variable or something.
1938 EmitAutoVarInit(variable);
1939
1940 const VarDecl *D = cast<VarDecl>(SD->getSingleDecl());
1941 DeclRefExpr tempDRE(getContext(), const_cast<VarDecl *>(D), false,
1942 D->getType(), VK_LValue, SourceLocation());
1943 elementLValue = EmitLValue(&tempDRE);
1944 elementType = D->getType();
1945 elementIsVariable = true;
1946
1947 if (D->isARCPseudoStrong())
1948 elementLValue.getQuals().setObjCLifetime(Qualifiers::OCL_ExplicitNone);
1949 } else {
1950 elementLValue = LValue(); // suppress warning
1951 elementType = cast<Expr>(S.getElement())->getType();
1952 elementIsVariable = false;
1953 }
1954 llvm::Type *convertedElementType = ConvertType(elementType);
1955
1956 // Fetch the buffer out of the enumeration state.
1957 // TODO: this pointer should actually be invariant between
1958 // refreshes, which would help us do certain loop optimizations.
1959 Address StateItemsPtr =
1960 Builder.CreateStructGEP(StatePtr, 1, "stateitems.ptr");
1961 llvm::Value *EnumStateItems =
1962 Builder.CreateLoad(StateItemsPtr, "stateitems");
1963
1964 // Fetch the value at the current index from the buffer.
1965 llvm::Value *CurrentItemPtr = Builder.CreateGEP(
1966 ObjCIdType, EnumStateItems, index, "currentitem.ptr");
1967 llvm::Value *CurrentItem =
1968 Builder.CreateAlignedLoad(ObjCIdType, CurrentItemPtr, getPointerAlign());
1969
1970 if (SanOpts.has(SanitizerKind::ObjCCast)) {
1971 // Before using an item from the collection, check that the implicit cast
1972 // from id to the element type is valid. This is done with instrumentation
1973 // roughly corresponding to:
1974 //
1975 // if (![item isKindOfClass:expectedCls]) { /* emit diagnostic */ }
1976 const ObjCObjectPointerType *ObjPtrTy =
1977 elementType->getAsObjCInterfacePointerType();
1978 const ObjCInterfaceType *InterfaceTy =
1979 ObjPtrTy ? ObjPtrTy->getInterfaceType() : nullptr;
1980 if (InterfaceTy) {
1981 SanitizerScope SanScope(this);
1982 auto &C = CGM.getContext();
1983 assert(InterfaceTy->getDecl() && "No decl for ObjC interface type")(static_cast <bool> (InterfaceTy->getDecl() &&
"No decl for ObjC interface type") ? void (0) : __assert_fail
("InterfaceTy->getDecl() && \"No decl for ObjC interface type\""
, "clang/lib/CodeGen/CGObjC.cpp", 1983, __extension__ __PRETTY_FUNCTION__
))
;
1984 Selector IsKindOfClassSel = GetUnarySelector("isKindOfClass", C);
1985 CallArgList IsKindOfClassArgs;
1986 llvm::Value *Cls =
1987 CGM.getObjCRuntime().GetClass(*this, InterfaceTy->getDecl());
1988 IsKindOfClassArgs.add(RValue::get(Cls), C.getObjCClassType());
1989 llvm::Value *IsClass =
1990 CGM.getObjCRuntime()
1991 .GenerateMessageSend(*this, ReturnValueSlot(), C.BoolTy,
1992 IsKindOfClassSel, CurrentItem,
1993 IsKindOfClassArgs)
1994 .getScalarVal();
1995 llvm::Constant *StaticData[] = {
1996 EmitCheckSourceLocation(S.getBeginLoc()),
1997 EmitCheckTypeDescriptor(QualType(InterfaceTy, 0))};
1998 EmitCheck({{IsClass, SanitizerKind::ObjCCast}},
1999 SanitizerHandler::InvalidObjCCast,
2000 ArrayRef<llvm::Constant *>(StaticData), CurrentItem);
2001 }
2002 }
2003
2004 // Cast that value to the right type.
2005 CurrentItem = Builder.CreateBitCast(CurrentItem, convertedElementType,
2006 "currentitem");
2007
2008 // Make sure we have an l-value. Yes, this gets evaluated every
2009 // time through the loop.
2010 if (!elementIsVariable) {
2011 elementLValue = EmitLValue(cast<Expr>(S.getElement()));
2012 EmitStoreThroughLValue(RValue::get(CurrentItem), elementLValue);
2013 } else {
2014 EmitStoreThroughLValue(RValue::get(CurrentItem), elementLValue,
2015 /*isInit*/ true);
2016 }
2017
2018 // If we do have an element variable, this assignment is the end of
2019 // its initialization.
2020 if (elementIsVariable)
2021 EmitAutoVarCleanups(variable);
2022
2023 // Perform the loop body, setting up break and continue labels.
2024 BreakContinueStack.push_back(BreakContinue(LoopEnd, AfterBody));
2025 {
2026 RunCleanupsScope Scope(*this);
2027 EmitStmt(S.getBody());
2028 }
2029 BreakContinueStack.pop_back();
2030
2031 // Destroy the element variable now.
2032 elementVariableScope.ForceCleanup();
2033
2034 // Check whether there are more elements.
2035 EmitBlock(AfterBody.getBlock());
2036
2037 llvm::BasicBlock *FetchMoreBB = createBasicBlock("forcoll.refetch");
2038
2039 // First we check in the local buffer.
2040 llvm::Value *indexPlusOne =
2041 Builder.CreateAdd(index, llvm::ConstantInt::get(NSUIntegerTy, 1));
2042
2043 // If we haven't overrun the buffer yet, we can continue.
2044 // Set the branch weights based on the simplifying assumption that this is
2045 // like a while-loop, i.e., ignoring that the false branch fetches more
2046 // elements and then returns to the loop.
2047 Builder.CreateCondBr(
2048 Builder.CreateICmpULT(indexPlusOne, count), LoopBodyBB, FetchMoreBB,
2049 createProfileWeights(getProfileCount(S.getBody()), EntryCount));
2050
2051 index->addIncoming(indexPlusOne, AfterBody.getBlock());
2052 count->addIncoming(count, AfterBody.getBlock());
2053
2054 // Otherwise, we have to fetch more elements.
2055 EmitBlock(FetchMoreBB);
2056
2057 CountRV =
2058 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
2059 getContext().getNSUIntegerType(),
2060 FastEnumSel, Collection, Args);
2061
2062 // If we got a zero count, we're done.
2063 llvm::Value *refetchCount = CountRV.getScalarVal();
2064
2065 // (note that the message send might split FetchMoreBB)
2066 index->addIncoming(zero, Builder.GetInsertBlock());
2067 count->addIncoming(refetchCount, Builder.GetInsertBlock());
2068
2069 Builder.CreateCondBr(Builder.CreateICmpEQ(refetchCount, zero),
2070 EmptyBB, LoopBodyBB);
2071
2072 // No more elements.
2073 EmitBlock(EmptyBB);
2074
2075 if (!elementIsVariable) {
2076 // If the element was not a declaration, set it to be null.
2077
2078 llvm::Value *null = llvm::Constant::getNullValue(convertedElementType);
2079 elementLValue = EmitLValue(cast<Expr>(S.getElement()));
2080 EmitStoreThroughLValue(RValue::get(null), elementLValue);
2081 }
2082
2083 if (DI)
2084 DI->EmitLexicalBlockEnd(Builder, S.getSourceRange().getEnd());
2085
2086 ForScope.ForceCleanup();
2087 EmitBlock(LoopEnd.getBlock());
2088}
2089
2090void CodeGenFunction::EmitObjCAtTryStmt(const ObjCAtTryStmt &S) {
2091 CGM.getObjCRuntime().EmitTryStmt(*this, S);
2092}
2093
2094void CodeGenFunction::EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S) {
2095 CGM.getObjCRuntime().EmitThrowStmt(*this, S);
2096}
2097
2098void CodeGenFunction::EmitObjCAtSynchronizedStmt(
2099 const ObjCAtSynchronizedStmt &S) {
2100 CGM.getObjCRuntime().EmitSynchronizedStmt(*this, S);
2101}
2102
2103namespace {
2104 struct CallObjCRelease final : EHScopeStack::Cleanup {
2105 CallObjCRelease(llvm::Value *object) : object(object) {}
2106 llvm::Value *object;
2107
2108 void Emit(CodeGenFunction &CGF, Flags flags) override {
2109 // Releases at the end of the full-expression are imprecise.
2110 CGF.EmitARCRelease(object, ARCImpreciseLifetime);
2111 }
2112 };
2113}
2114
2115/// Produce the code for a CK_ARCConsumeObject. Does a primitive
2116/// release at the end of the full-expression.
2117llvm::Value *CodeGenFunction::EmitObjCConsumeObject(QualType type,
2118 llvm::Value *object) {
2119 // If we're in a conditional branch, we need to make the cleanup
2120 // conditional.
2121 pushFullExprCleanup<CallObjCRelease>(getARCCleanupKind(), object);
2122 return object;
2123}
2124
2125llvm::Value *CodeGenFunction::EmitObjCExtendObjectLifetime(QualType type,
2126 llvm::Value *value) {
2127 return EmitARCRetainAutorelease(type, value);
2128}
2129
2130/// Given a number of pointers, inform the optimizer that they're
2131/// being intrinsically used up until this point in the program.
2132void CodeGenFunction::EmitARCIntrinsicUse(ArrayRef<llvm::Value*> values) {
2133 llvm::Function *&fn = CGM.getObjCEntrypoints().clang_arc_use;
2134 if (!fn)
2135 fn = CGM.getIntrinsic(llvm::Intrinsic::objc_clang_arc_use);
2136
2137 // This isn't really a "runtime" function, but as an intrinsic it
2138 // doesn't really matter as long as we align things up.
2139 EmitNounwindRuntimeCall(fn, values);
2140}
2141
2142/// Emit a call to "clang.arc.noop.use", which consumes the result of a call
2143/// that has operand bundle "clang.arc.attachedcall".
2144void CodeGenFunction::EmitARCNoopIntrinsicUse(ArrayRef<llvm::Value *> values) {
2145 llvm::Function *&fn = CGM.getObjCEntrypoints().clang_arc_noop_use;
2146 if (!fn)
2147 fn = CGM.getIntrinsic(llvm::Intrinsic::objc_clang_arc_noop_use);
2148 EmitNounwindRuntimeCall(fn, values);
2149}
2150
2151static void setARCRuntimeFunctionLinkage(CodeGenModule &CGM, llvm::Value *RTF) {
2152 if (auto *F = dyn_cast<llvm::Function>(RTF)) {
2153 // If the target runtime doesn't naturally support ARC, emit weak
2154 // references to the runtime support library. We don't really
2155 // permit this to fail, but we need a particular relocation style.
2156 if (!CGM.getLangOpts().ObjCRuntime.hasNativeARC() &&
2157 !CGM.getTriple().isOSBinFormatCOFF()) {
2158 F->setLinkage(llvm::Function::ExternalWeakLinkage);
2159 }
2160 }
2161}
2162
2163static void setARCRuntimeFunctionLinkage(CodeGenModule &CGM,
2164 llvm::FunctionCallee RTF) {
2165 setARCRuntimeFunctionLinkage(CGM, RTF.getCallee());
2166}
2167
2168static llvm::Function *getARCIntrinsic(llvm::Intrinsic::ID IntID,
2169 CodeGenModule &CGM) {
2170 llvm::Function *fn = CGM.getIntrinsic(IntID);
2171 setARCRuntimeFunctionLinkage(CGM, fn);
2172 return fn;
2173}
2174
2175/// Perform an operation having the signature
2176/// i8* (i8*)
2177/// where a null input causes a no-op and returns null.
2178static llvm::Value *emitARCValueOperation(
2179 CodeGenFunction &CGF, llvm::Value *value, llvm::Type *returnType,
2180 llvm::Function *&fn, llvm::Intrinsic::ID IntID,
2181 llvm::CallInst::TailCallKind tailKind = llvm::CallInst::TCK_None) {
2182 if (isa<llvm::ConstantPointerNull>(value))
2183 return value;
2184
2185 if (!fn)
2186 fn = getARCIntrinsic(IntID, CGF.CGM);
2187
2188 // Cast the argument to 'id'.
2189 llvm::Type *origType = returnType ? returnType : value->getType();
2190 value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy);
2191
2192 // Call the function.
2193 llvm::CallInst *call = CGF.EmitNounwindRuntimeCall(fn, value);
2194 call->setTailCallKind(tailKind);
2195
2196 // Cast the result back to the original type.
2197 return CGF.Builder.CreateBitCast(call, origType);
2198}
2199
2200/// Perform an operation having the following signature:
2201/// i8* (i8**)
2202static llvm::Value *emitARCLoadOperation(CodeGenFunction &CGF, Address addr,
2203 llvm::Function *&fn,
2204 llvm::Intrinsic::ID IntID) {
2205 if (!fn)
2206 fn = getARCIntrinsic(IntID, CGF.CGM);
2207
2208 // Cast the argument to 'id*'.
2209 llvm::Type *origType = addr.getElementType();
2210 addr = CGF.Builder.CreateElementBitCast(addr, CGF.Int8PtrTy);
2211
2212 // Call the function.
2213 llvm::Value *result = CGF.EmitNounwindRuntimeCall(fn, addr.getPointer());
2214
2215 // Cast the result back to a dereference of the original type.
2216 if (origType != CGF.Int8PtrTy)
2217 result = CGF.Builder.CreateBitCast(result, origType);
2218
2219 return result;
2220}
2221
2222/// Perform an operation having the following signature:
2223/// i8* (i8**, i8*)
2224static llvm::Value *emitARCStoreOperation(CodeGenFunction &CGF, Address addr,
2225 llvm::Value *value,
2226 llvm::Function *&fn,
2227 llvm::Intrinsic::ID IntID,
2228 bool ignored) {
2229 assert(addr.getElementType() == value->getType())(static_cast <bool> (addr.getElementType() == value->
getType()) ? void (0) : __assert_fail ("addr.getElementType() == value->getType()"
, "clang/lib/CodeGen/CGObjC.cpp", 2229, __extension__ __PRETTY_FUNCTION__
))
;
2230
2231 if (!fn)
2232 fn = getARCIntrinsic(IntID, CGF.CGM);
2233
2234 llvm::Type *origType = value->getType();
2235
2236 llvm::Value *args[] = {
2237 CGF.Builder.CreateBitCast(addr.getPointer(), CGF.Int8PtrPtrTy),
2238 CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy)
2239 };
2240 llvm::CallInst *result = CGF.EmitNounwindRuntimeCall(fn, args);
2241
2242 if (ignored) return nullptr;
2243
2244 return CGF.Builder.CreateBitCast(result, origType);
2245}
2246
2247/// Perform an operation having the following signature:
2248/// void (i8**, i8**)
2249static void emitARCCopyOperation(CodeGenFunction &CGF, Address dst, Address src,
2250 llvm::Function *&fn,
2251 llvm::Intrinsic::ID IntID) {
2252 assert(dst.getType() == src.getType())(static_cast <bool> (dst.getType() == src.getType()) ? void
(0) : __assert_fail ("dst.getType() == src.getType()", "clang/lib/CodeGen/CGObjC.cpp"
, 2252, __extension__ __PRETTY_FUNCTION__))
;
2253
2254 if (!fn)
2255 fn = getARCIntrinsic(IntID, CGF.CGM);
2256
2257 llvm::Value *args[] = {
2258 CGF.Builder.CreateBitCast(dst.getPointer(), CGF.Int8PtrPtrTy),
2259 CGF.Builder.CreateBitCast(src.getPointer(), CGF.Int8PtrPtrTy)
2260 };
2261 CGF.EmitNounwindRuntimeCall(fn, args);
2262}
2263
2264/// Perform an operation having the signature
2265/// i8* (i8*)
2266/// where a null input causes a no-op and returns null.
2267static llvm::Value *emitObjCValueOperation(CodeGenFunction &CGF,
2268 llvm::Value *value,
2269 llvm::Type *returnType,
2270 llvm::FunctionCallee &fn,
2271 StringRef fnName) {
2272 if (isa<llvm::ConstantPointerNull>(value))
2273 return value;
2274
2275 if (!fn) {
2276 llvm::FunctionType *fnType =
2277 llvm::FunctionType::get(CGF.Int8PtrTy, CGF.Int8PtrTy, false);
2278 fn = CGF.CGM.CreateRuntimeFunction(fnType, fnName);
2279
2280 // We have Native ARC, so set nonlazybind attribute for performance
2281 if (llvm::Function *f = dyn_cast<llvm::Function>(fn.getCallee()))
2282 if (fnName == "objc_retain")
2283 f->addFnAttr(llvm::Attribute::NonLazyBind);
2284 }
2285
2286 // Cast the argument to 'id'.
2287 llvm::Type *origType = returnType ? returnType : value->getType();
2288 value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy);
2289
2290 // Call the function.
2291 llvm::CallBase *Inst = CGF.EmitCallOrInvoke(fn, value);
2292
2293 // Mark calls to objc_autorelease as tail on the assumption that methods
2294 // overriding autorelease do not touch anything on the stack.
2295 if (fnName == "objc_autorelease")
2296 if (auto *Call = dyn_cast<llvm::CallInst>(Inst))
2297 Call->setTailCall();
2298
2299 // Cast the result back to the original type.
2300 return CGF.Builder.CreateBitCast(Inst, origType);
2301}
2302
2303/// Produce the code to do a retain. Based on the type, calls one of:
2304/// call i8* \@objc_retain(i8* %value)
2305/// call i8* \@objc_retainBlock(i8* %value)
2306llvm::Value *CodeGenFunction::EmitARCRetain(QualType type, llvm::Value *value) {
2307 if (type->isBlockPointerType())
2308 return EmitARCRetainBlock(value, /*mandatory*/ false);
2309 else
2310 return EmitARCRetainNonBlock(value);
2311}
2312
2313/// Retain the given object, with normal retain semantics.
2314/// call i8* \@objc_retain(i8* %value)
2315llvm::Value *CodeGenFunction::EmitARCRetainNonBlock(llvm::Value *value) {
2316 return emitARCValueOperation(*this, value, nullptr,
2317 CGM.getObjCEntrypoints().objc_retain,
2318 llvm::Intrinsic::objc_retain);
2319}
2320
2321/// Retain the given block, with _Block_copy semantics.
2322/// call i8* \@objc_retainBlock(i8* %value)
2323///
2324/// \param mandatory - If false, emit the call with metadata
2325/// indicating that it's okay for the optimizer to eliminate this call
2326/// if it can prove that the block never escapes except down the stack.
2327llvm::Value *CodeGenFunction::EmitARCRetainBlock(llvm::Value *value,
2328 bool mandatory) {
2329 llvm::Value *result
2330 = emitARCValueOperation(*this, value, nullptr,
2331 CGM.getObjCEntrypoints().objc_retainBlock,
2332 llvm::Intrinsic::objc_retainBlock);
2333
2334 // If the copy isn't mandatory, add !clang.arc.copy_on_escape to
2335 // tell the optimizer that it doesn't need to do this copy if the
2336 // block doesn't escape, where being passed as an argument doesn't
2337 // count as escaping.
2338 if (!mandatory && isa<llvm::Instruction>(result)) {
2339 llvm::CallInst *call
2340 = cast<llvm::CallInst>(result->stripPointerCasts());
2341 assert(call->getCalledOperand() ==(static_cast <bool> (call->getCalledOperand() == CGM
.getObjCEntrypoints().objc_retainBlock) ? void (0) : __assert_fail
("call->getCalledOperand() == CGM.getObjCEntrypoints().objc_retainBlock"
, "clang/lib/CodeGen/CGObjC.cpp", 2342, __extension__ __PRETTY_FUNCTION__
))
2342 CGM.getObjCEntrypoints().objc_retainBlock)(static_cast <bool> (call->getCalledOperand() == CGM
.getObjCEntrypoints().objc_retainBlock) ? void (0) : __assert_fail
("call->getCalledOperand() == CGM.getObjCEntrypoints().objc_retainBlock"
, "clang/lib/CodeGen/CGObjC.cpp", 2342, __extension__ __PRETTY_FUNCTION__
))
;
2343
2344 call->setMetadata("clang.arc.copy_on_escape",
2345 llvm::MDNode::get(Builder.getContext(), std::nullopt));
2346 }
2347
2348 return result;
2349}
2350
2351static void emitAutoreleasedReturnValueMarker(CodeGenFunction &CGF) {
2352 // Fetch the void(void) inline asm which marks that we're going to
2353 // do something with the autoreleased return value.
2354 llvm::InlineAsm *&marker
2355 = CGF.CGM.getObjCEntrypoints().retainAutoreleasedReturnValueMarker;
2356 if (!marker) {
2357 StringRef assembly
2358 = CGF.CGM.getTargetCodeGenInfo()
2359 .getARCRetainAutoreleasedReturnValueMarker();
2360
2361 // If we have an empty assembly string, there's nothing to do.
2362 if (assembly.empty()) {
2363
2364 // Otherwise, at -O0, build an inline asm that we're going to call
2365 // in a moment.
2366 } else if (CGF.CGM.getCodeGenOpts().OptimizationLevel == 0) {
2367 llvm::FunctionType *type =
2368 llvm::FunctionType::get(CGF.VoidTy, /*variadic*/false);
2369
2370 marker = llvm::InlineAsm::get(type, assembly, "", /*sideeffects*/ true);
2371
2372 // If we're at -O1 and above, we don't want to litter the code
2373 // with this marker yet, so leave a breadcrumb for the ARC
2374 // optimizer to pick up.
2375 } else {
2376 const char *retainRVMarkerKey = llvm::objcarc::getRVMarkerModuleFlagStr();
2377 if (!CGF.CGM.getModule().getModuleFlag(retainRVMarkerKey)) {
2378 auto *str = llvm::MDString::get(CGF.getLLVMContext(), assembly);
2379 CGF.CGM.getModule().addModuleFlag(llvm::Module::Error,
2380 retainRVMarkerKey, str);
2381 }
2382 }
2383 }
2384
2385 // Call the marker asm if we made one, which we do only at -O0.
2386 if (marker)
2387 CGF.Builder.CreateCall(marker, std::nullopt,
2388 CGF.getBundlesForFunclet(marker));
2389}
2390
2391static llvm::Value *emitOptimizedARCReturnCall(llvm::Value *value,
2392 bool IsRetainRV,
2393 CodeGenFunction &CGF) {
2394 emitAutoreleasedReturnValueMarker(CGF);
2395
2396 // Add operand bundle "clang.arc.attachedcall" to the call instead of emitting
2397 // retainRV or claimRV calls in the IR. We currently do this only when the
2398 // optimization level isn't -O0 since global-isel, which is currently run at
2399 // -O0, doesn't know about the operand bundle.
2400 ObjCEntrypoints &EPs = CGF.CGM.getObjCEntrypoints();
2401 llvm::Function *&EP = IsRetainRV
2402 ? EPs.objc_retainAutoreleasedReturnValue
2403 : EPs.objc_unsafeClaimAutoreleasedReturnValue;
2404 llvm::Intrinsic::ID IID =
2405 IsRetainRV ? llvm::Intrinsic::objc_retainAutoreleasedReturnValue
2406 : llvm::Intrinsic::objc_unsafeClaimAutoreleasedReturnValue;
2407 EP = getARCIntrinsic(IID, CGF.CGM);
2408
2409 llvm::Triple::ArchType Arch = CGF.CGM.getTriple().getArch();
2410
2411 // FIXME: Do this on all targets and at -O0 too. This can be enabled only if
2412 // the target backend knows how to handle the operand bundle.
2413 if (CGF.CGM.getCodeGenOpts().OptimizationLevel > 0 &&
2414 (Arch == llvm::Triple::aarch64 || Arch == llvm::Triple::x86_64)) {
2415 llvm::Value *bundleArgs[] = {EP};
2416 llvm::OperandBundleDef OB("clang.arc.attachedcall", bundleArgs);
2417 auto *oldCall = cast<llvm::CallBase>(value);
2418 llvm::CallBase *newCall = llvm::CallBase::addOperandBundle(
2419 oldCall, llvm::LLVMContext::OB_clang_arc_attachedcall, OB, oldCall);
2420 newCall->copyMetadata(*oldCall);
2421 oldCall->replaceAllUsesWith(newCall);
2422 oldCall->eraseFromParent();
2423 CGF.EmitARCNoopIntrinsicUse(newCall);
2424 return newCall;
2425 }
2426
2427 bool isNoTail =
2428 CGF.CGM.getTargetCodeGenInfo().markARCOptimizedReturnCallsAsNoTail();
2429 llvm::CallInst::TailCallKind tailKind =
2430 isNoTail ? llvm::CallInst::TCK_NoTail : llvm::CallInst::TCK_None;
2431 return emitARCValueOperation(CGF, value, nullptr, EP, IID, tailKind);
2432}
2433
2434/// Retain the given object which is the result of a function call.
2435/// call i8* \@objc_retainAutoreleasedReturnValue(i8* %value)
2436///
2437/// Yes, this function name is one character away from a different
2438/// call with completely different semantics.
2439llvm::Value *
2440CodeGenFunction::EmitARCRetainAutoreleasedReturnValue(llvm::Value *value) {
2441 return emitOptimizedARCReturnCall(value, true, *this);
2442}
2443
2444/// Claim a possibly-autoreleased return value at +0. This is only
2445/// valid to do in contexts which do not rely on the retain to keep
2446/// the object valid for all of its uses; for example, when
2447/// the value is ignored, or when it is being assigned to an
2448/// __unsafe_unretained variable.
2449///
2450/// call i8* \@objc_unsafeClaimAutoreleasedReturnValue(i8* %value)
2451llvm::Value *
2452CodeGenFunction::EmitARCUnsafeClaimAutoreleasedReturnValue(llvm::Value *value) {
2453 return emitOptimizedARCReturnCall(value, false, *this);
2454}
2455
2456/// Release the given object.
2457/// call void \@objc_release(i8* %value)
2458void CodeGenFunction::EmitARCRelease(llvm::Value *value,
2459 ARCPreciseLifetime_t precise) {
2460 if (isa<llvm::ConstantPointerNull>(value)) return;
2461
2462 llvm::Function *&fn = CGM.getObjCEntrypoints().objc_release;
2463 if (!fn)
2464 fn = getARCIntrinsic(llvm::Intrinsic::objc_release, CGM);
2465
2466 // Cast the argument to 'id'.
2467 value = Builder.CreateBitCast(value, Int8PtrTy);
2468
2469 // Call objc_release.
2470 llvm::CallInst *call = EmitNounwindRuntimeCall(fn, value);
2471
2472 if (precise == ARCImpreciseLifetime) {
2473 call->setMetadata("clang.imprecise_release",
2474 llvm::MDNode::get(Builder.getContext(), std::nullopt));
2475 }
2476}
2477
2478/// Destroy a __strong variable.
2479///
2480/// At -O0, emit a call to store 'null' into the address;
2481/// instrumenting tools prefer this because the address is exposed,
2482/// but it's relatively cumbersome to optimize.
2483///
2484/// At -O1 and above, just load and call objc_release.
2485///
2486/// call void \@objc_storeStrong(i8** %addr, i8* null)
2487void CodeGenFunction::EmitARCDestroyStrong(Address addr,
2488 ARCPreciseLifetime_t precise) {
2489 if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
2490 llvm::Value *null = getNullForVariable(addr);
2491 EmitARCStoreStrongCall(addr, null, /*ignored*/ true);
2492 return;
2493 }
2494
2495 llvm::Value *value = Builder.CreateLoad(addr);
2496 EmitARCRelease(value, precise);
2497}
2498
2499/// Store into a strong object. Always calls this:
2500/// call void \@objc_storeStrong(i8** %addr, i8* %value)
2501llvm::Value *CodeGenFunction::EmitARCStoreStrongCall(Address addr,
2502 llvm::Value *value,
2503 bool ignored) {
2504 assert(addr.getElementType() == value->getType())(static_cast <bool> (addr.getElementType() == value->
getType()) ? void (0) : __assert_fail ("addr.getElementType() == value->getType()"
, "clang/lib/CodeGen/CGObjC.cpp", 2504, __extension__ __PRETTY_FUNCTION__
))
;
2505
2506 llvm::Function *&fn = CGM.getObjCEntrypoints().objc_storeStrong;
2507 if (!fn)
2508 fn = getARCIntrinsic(llvm::Intrinsic::objc_storeStrong, CGM);
2509
2510 llvm::Value *args[] = {
2511 Builder.CreateBitCast(addr.getPointer(), Int8PtrPtrTy),
2512 Builder.CreateBitCast(value, Int8PtrTy)
2513 };
2514 EmitNounwindRuntimeCall(fn, args);
2515
2516 if (ignored) return nullptr;
2517 return value;
2518}
2519
2520/// Store into a strong object. Sometimes calls this:
2521/// call void \@objc_storeStrong(i8** %addr, i8* %value)
2522/// Other times, breaks it down into components.
2523llvm::Value *CodeGenFunction::EmitARCStoreStrong(LValue dst,
2524 llvm::Value *newValue,
2525 bool ignored) {
2526 QualType type = dst.getType();
2527 bool isBlock = type->isBlockPointerType();
2528
2529 // Use a store barrier at -O0 unless this is a block type or the
2530 // lvalue is inadequately aligned.
2531 if (shouldUseFusedARCCalls() &&
2532 !isBlock &&
2533 (dst.getAlignment().isZero() ||
2534 dst.getAlignment() >= CharUnits::fromQuantity(PointerAlignInBytes))) {
2535 return EmitARCStoreStrongCall(dst.getAddress(*this), newValue, ignored);
2536 }
2537
2538 // Otherwise, split it out.
2539
2540 // Retain the new value.
2541 newValue = EmitARCRetain(type, newValue);
2542
2543 // Read the old value.
2544 llvm::Value *oldValue = EmitLoadOfScalar(dst, SourceLocation());
2545
2546 // Store. We do this before the release so that any deallocs won't
2547 // see the old value.
2548 EmitStoreOfScalar(newValue, dst);
2549
2550 // Finally, release the old value.
2551 EmitARCRelease(oldValue, dst.isARCPreciseLifetime());
2552
2553 return newValue;
2554}
2555
2556/// Autorelease the given object.
2557/// call i8* \@objc_autorelease(i8* %value)
2558llvm::Value *CodeGenFunction::EmitARCAutorelease(llvm::Value *value) {
2559 return emitARCValueOperation(*this, value, nullptr,
2560 CGM.getObjCEntrypoints().objc_autorelease,
2561 llvm::Intrinsic::objc_autorelease);
2562}
2563
2564/// Autorelease the given object.
2565/// call i8* \@objc_autoreleaseReturnValue(i8* %value)
2566llvm::Value *
2567CodeGenFunction::EmitARCAutoreleaseReturnValue(llvm::Value *value) {
2568 return emitARCValueOperation(*this, value, nullptr,
2569 CGM.getObjCEntrypoints().objc_autoreleaseReturnValue,
2570 llvm::Intrinsic::objc_autoreleaseReturnValue,
2571 llvm::CallInst::TCK_Tail);
2572}
2573
2574/// Do a fused retain/autorelease of the given object.
2575/// call i8* \@objc_retainAutoreleaseReturnValue(i8* %value)
2576llvm::Value *
2577CodeGenFunction::EmitARCRetainAutoreleaseReturnValue(llvm::Value *value) {
2578 return emitARCValueOperation(*this, value, nullptr,
2579 CGM.getObjCEntrypoints().objc_retainAutoreleaseReturnValue,
2580 llvm::Intrinsic::objc_retainAutoreleaseReturnValue,
2581 llvm::CallInst::TCK_Tail);
2582}
2583
2584/// Do a fused retain/autorelease of the given object.
2585/// call i8* \@objc_retainAutorelease(i8* %value)
2586/// or
2587/// %retain = call i8* \@objc_retainBlock(i8* %value)
2588/// call i8* \@objc_autorelease(i8* %retain)
2589llvm::Value *CodeGenFunction::EmitARCRetainAutorelease(QualType type,
2590 llvm::Value *value) {
2591 if (!type->isBlockPointerType())
2592 return EmitARCRetainAutoreleaseNonBlock(value);
2593
2594 if (isa<llvm::ConstantPointerNull>(value)) return value;
2595
2596 llvm::Type *origType = value->getType();
2597 value = Builder.CreateBitCast(value, Int8PtrTy);
2598 value = EmitARCRetainBlock(value, /*mandatory*/ true);
2599 value = EmitARCAutorelease(value);
2600 return Builder.CreateBitCast(value, origType);
2601}
2602
2603/// Do a fused retain/autorelease of the given object.
2604/// call i8* \@objc_retainAutorelease(i8* %value)
2605llvm::Value *
2606CodeGenFunction::EmitARCRetainAutoreleaseNonBlock(llvm::Value *value) {
2607 return emitARCValueOperation(*this, value, nullptr,
2608 CGM.getObjCEntrypoints().objc_retainAutorelease,
2609 llvm::Intrinsic::objc_retainAutorelease);
2610}
2611
2612/// i8* \@objc_loadWeak(i8** %addr)
2613/// Essentially objc_autorelease(objc_loadWeakRetained(addr)).
2614llvm::Value *CodeGenFunction::EmitARCLoadWeak(Address addr) {
2615 return emitARCLoadOperation(*this, addr,
2616 CGM.getObjCEntrypoints().objc_loadWeak,
2617 llvm::Intrinsic::objc_loadWeak);
2618}
2619
2620/// i8* \@objc_loadWeakRetained(i8** %addr)
2621llvm::Value *CodeGenFunction::EmitARCLoadWeakRetained(Address addr) {
2622 return emitARCLoadOperation(*this, addr,
2623 CGM.getObjCEntrypoints().objc_loadWeakRetained,
2624 llvm::Intrinsic::objc_loadWeakRetained);
2625}
2626
2627/// i8* \@objc_storeWeak(i8** %addr, i8* %value)
2628/// Returns %value.
2629llvm::Value *CodeGenFunction::EmitARCStoreWeak(Address addr,
2630 llvm::Value *value,
2631 bool ignored) {
2632 return emitARCStoreOperation(*this, addr, value,
2633 CGM.getObjCEntrypoints().objc_storeWeak,
2634 llvm::Intrinsic::objc_storeWeak, ignored);
2635}
2636
2637/// i8* \@objc_initWeak(i8** %addr, i8* %value)
2638/// Returns %value. %addr is known to not have a current weak entry.
2639/// Essentially equivalent to:
2640/// *addr = nil; objc_storeWeak(addr, value);
2641void CodeGenFunction::EmitARCInitWeak(Address addr, llvm::Value *value) {
2642 // If we're initializing to null, just write null to memory; no need
2643 // to get the runtime involved. But don't do this if optimization
2644 // is enabled, because accounting for this would make the optimizer
2645 // much more complicated.
2646 if (isa<llvm::ConstantPointerNull>(value) &&
2647 CGM.getCodeGenOpts().OptimizationLevel == 0) {
2648 Builder.CreateStore(value, addr);
2649 return;
2650 }
2651
2652 emitARCStoreOperation(*this, addr, value,
2653 CGM.getObjCEntrypoints().objc_initWeak,
2654 llvm::Intrinsic::objc_initWeak, /*ignored*/ true);
2655}
2656
2657/// void \@objc_destroyWeak(i8** %addr)
2658/// Essentially objc_storeWeak(addr, nil).
2659void CodeGenFunction::EmitARCDestroyWeak(Address addr) {
2660 llvm::Function *&fn = CGM.getObjCEntrypoints().objc_destroyWeak;
2661 if (!fn)
2662 fn = getARCIntrinsic(llvm::Intrinsic::objc_destroyWeak, CGM);
2663
2664 // Cast the argument to 'id*'.
2665 addr = Builder.CreateElementBitCast(addr, Int8PtrTy);
2666
2667 EmitNounwindRuntimeCall(fn, addr.getPointer());
2668}
2669
2670/// void \@objc_moveWeak(i8** %dest, i8** %src)
2671/// Disregards the current value in %dest. Leaves %src pointing to nothing.
2672/// Essentially (objc_copyWeak(dest, src), objc_destroyWeak(src)).
2673void CodeGenFunction::EmitARCMoveWeak(Address dst, Address src) {
2674 emitARCCopyOperation(*this, dst, src,
2675 CGM.getObjCEntrypoints().objc_moveWeak,
2676 llvm::Intrinsic::objc_moveWeak);
2677}
2678
2679/// void \@objc_copyWeak(i8** %dest, i8** %src)
2680/// Disregards the current value in %dest. Essentially
2681/// objc_release(objc_initWeak(dest, objc_readWeakRetained(src)))
2682void CodeGenFunction::EmitARCCopyWeak(Address dst, Address src) {
2683 emitARCCopyOperation(*this, dst, src,
2684 CGM.getObjCEntrypoints().objc_copyWeak,
2685 llvm::Intrinsic::objc_copyWeak);
2686}
2687
2688void CodeGenFunction::emitARCCopyAssignWeak(QualType Ty, Address DstAddr,
2689 Address SrcAddr) {
2690 llvm::Value *Object = EmitARCLoadWeakRetained(SrcAddr);
2691 Object = EmitObjCConsumeObject(Ty, Object);
2692 EmitARCStoreWeak(DstAddr, Object, false);
2693}
2694
2695void CodeGenFunction::emitARCMoveAssignWeak(QualType Ty, Address DstAddr,
2696 Address SrcAddr) {
2697 llvm::Value *Object = EmitARCLoadWeakRetained(SrcAddr);
2698 Object = EmitObjCConsumeObject(Ty, Object);
2699 EmitARCStoreWeak(DstAddr, Object, false);
2700 EmitARCDestroyWeak(SrcAddr);
2701}
2702
2703/// Produce the code to do a objc_autoreleasepool_push.
2704/// call i8* \@objc_autoreleasePoolPush(void)
2705llvm::Value *CodeGenFunction::EmitObjCAutoreleasePoolPush() {
2706 llvm::Function *&fn = CGM.getObjCEntrypoints().objc_autoreleasePoolPush;
2707 if (!fn)
2708 fn = getARCIntrinsic(llvm::Intrinsic::objc_autoreleasePoolPush, CGM);
2709
2710 return EmitNounwindRuntimeCall(fn);
2711}
2712
2713/// Produce the code to do a primitive release.
2714/// call void \@objc_autoreleasePoolPop(i8* %ptr)
2715void CodeGenFunction::EmitObjCAutoreleasePoolPop(llvm::Value *value) {
2716 assert(value->getType() == Int8PtrTy)(static_cast <bool> (value->getType() == Int8PtrTy) ?
void (0) : __assert_fail ("value->getType() == Int8PtrTy"
, "clang/lib/CodeGen/CGObjC.cpp", 2716, __extension__ __PRETTY_FUNCTION__
))
;
2717
2718 if (getInvokeDest()) {
2719 // Call the runtime method not the intrinsic if we are handling exceptions
2720 llvm::FunctionCallee &fn =
2721 CGM.getObjCEntrypoints().objc_autoreleasePoolPopInvoke;
2722 if (!fn) {
2723 llvm::FunctionType *fnType =
2724 llvm::FunctionType::get(Builder.getVoidTy(), Int8PtrTy, false);
2725 fn = CGM.CreateRuntimeFunction(fnType, "objc_autoreleasePoolPop");
2726 setARCRuntimeFunctionLinkage(CGM, fn);
2727 }
2728
2729 // objc_autoreleasePoolPop can throw.
2730 EmitRuntimeCallOrInvoke(fn, value);
2731 } else {
2732 llvm::FunctionCallee &fn = CGM.getObjCEntrypoints().objc_autoreleasePoolPop;
2733 if (!fn)
2734 fn = getARCIntrinsic(llvm::Intrinsic::objc_autoreleasePoolPop, CGM);
2735
2736 EmitRuntimeCall(fn, value);
2737 }
2738}
2739
2740/// Produce the code to do an MRR version objc_autoreleasepool_push.
2741/// Which is: [[NSAutoreleasePool alloc] init];
2742/// Where alloc is declared as: + (id) alloc; in NSAutoreleasePool class.
2743/// init is declared as: - (id) init; in its NSObject super class.
2744///
2745llvm::Value *CodeGenFunction::EmitObjCMRRAutoreleasePoolPush() {
2746 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
2747 llvm::Value *Receiver = Runtime.EmitNSAutoreleasePoolClassRef(*this);
2748 // [NSAutoreleasePool alloc]
2749 IdentifierInfo *II = &CGM.getContext().Idents.get("alloc");
2750 Selector AllocSel = getContext().Selectors.getSelector(0, &II);
2751 CallArgList Args;
2752 RValue AllocRV =
2753 Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
2754 getContext().getObjCIdType(),
2755 AllocSel, Receiver, Args);
2756
2757 // [Receiver init]
2758 Receiver = AllocRV.getScalarVal();
2759 II = &CGM.getContext().Idents.get("init");
2760 Selector InitSel = getContext().Selectors.getSelector(0, &II);
2761 RValue InitRV =
2762 Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
2763 getContext().getObjCIdType(),
2764 InitSel, Receiver, Args);
2765 return InitRV.getScalarVal();
2766}
2767
2768/// Allocate the given objc object.
2769/// call i8* \@objc_alloc(i8* %value)
2770llvm::Value *CodeGenFunction::EmitObjCAlloc(llvm::Value *value,
2771 llvm::Type *resultType) {
2772 return emitObjCValueOperation(*this, value, resultType,
2773 CGM.getObjCEntrypoints().objc_alloc,
2774 "objc_alloc");
2775}
2776
2777/// Allocate the given objc object.
2778/// call i8* \@objc_allocWithZone(i8* %value)
2779llvm::Value *CodeGenFunction::EmitObjCAllocWithZone(llvm::Value *value,
2780 llvm::Type *resultType) {
2781 return emitObjCValueOperation(*this, value, resultType,
2782 CGM.getObjCEntrypoints().objc_allocWithZone,
2783 "objc_allocWithZone");
2784}
2785
2786llvm::Value *CodeGenFunction::EmitObjCAllocInit(llvm::Value *value,
2787 llvm::Type *resultType) {
2788 return emitObjCValueOperation(*this, value, resultType,
2789 CGM.getObjCEntrypoints().objc_alloc_init,
2790 "objc_alloc_init");
2791}
2792
2793/// Produce the code to do a primitive release.
2794/// [tmp drain];
2795void CodeGenFunction::EmitObjCMRRAutoreleasePoolPop(llvm::Value *Arg) {
2796 IdentifierInfo *II = &CGM.getContext().Idents.get("drain");
2797 Selector DrainSel = getContext().Selectors.getSelector(0, &II);
2798 CallArgList Args;
2799 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
2800 getContext().VoidTy, DrainSel, Arg, Args);
2801}
2802
2803void CodeGenFunction::destroyARCStrongPrecise(CodeGenFunction &CGF,
2804 Address addr,
2805 QualType type) {
2806 CGF.EmitARCDestroyStrong(addr, ARCPreciseLifetime);
2807}
2808
2809void CodeGenFunction::destroyARCStrongImprecise(CodeGenFunction &CGF,
2810 Address addr,
2811 QualType type) {
2812 CGF.EmitARCDestroyStrong(addr, ARCImpreciseLifetime);
2813}
2814
2815void CodeGenFunction::destroyARCWeak(CodeGenFunction &CGF,
2816 Address addr,
2817 QualType type) {
2818 CGF.EmitARCDestroyWeak(addr);
2819}
2820
2821void CodeGenFunction::emitARCIntrinsicUse(CodeGenFunction &CGF, Address addr,
2822 QualType type) {
2823 llvm::Value *value = CGF.Builder.CreateLoad(addr);
2824 CGF.EmitARCIntrinsicUse(value);
2825}
2826
2827/// Autorelease the given object.
2828/// call i8* \@objc_autorelease(i8* %value)
2829llvm::Value *CodeGenFunction::EmitObjCAutorelease(llvm::Value *value,
2830 llvm::Type *returnType) {
2831 return emitObjCValueOperation(
2832 *this, value, returnType,
2833 CGM.getObjCEntrypoints().objc_autoreleaseRuntimeFunction,
2834 "objc_autorelease");
2835}
2836
2837/// Retain the given object, with normal retain semantics.
2838/// call i8* \@objc_retain(i8* %value)
2839llvm::Value *CodeGenFunction::EmitObjCRetainNonBlock(llvm::Value *value,
2840 llvm::Type *returnType) {
2841 return emitObjCValueOperation(
2842 *this, value, returnType,
2843 CGM.getObjCEntrypoints().objc_retainRuntimeFunction, "objc_retain");
2844}
2845
2846/// Release the given object.
2847/// call void \@objc_release(i8* %value)
2848void CodeGenFunction::EmitObjCRelease(llvm::Value *value,
2849 ARCPreciseLifetime_t precise) {
2850 if (isa<llvm::ConstantPointerNull>(value)) return;
2851
2852 llvm::FunctionCallee &fn =
2853 CGM.getObjCEntrypoints().objc_releaseRuntimeFunction;
2854 if (!fn) {
2855 llvm::FunctionType *fnType =
2856 llvm::FunctionType::get(Builder.getVoidTy(), Int8PtrTy, false);
2857 fn = CGM.CreateRuntimeFunction(fnType, "objc_release");
2858 setARCRuntimeFunctionLinkage(CGM, fn);
2859 // We have Native ARC, so set nonlazybind attribute for performance
2860 if (llvm::Function *f = dyn_cast<llvm::Function>(fn.getCallee()))
2861 f->addFnAttr(llvm::Attribute::NonLazyBind);
2862 }
2863
2864 // Cast the argument to 'id'.
2865 value = Builder.CreateBitCast(value, Int8PtrTy);
2866
2867 // Call objc_release.
2868 llvm::CallBase *call = EmitCallOrInvoke(fn, value);
2869
2870 if (precise == ARCImpreciseLifetime) {
2871 call->setMetadata("clang.imprecise_release",
2872 llvm::MDNode::get(Builder.getContext(), std::nullopt));
2873 }
2874}
2875
2876namespace {
2877 struct CallObjCAutoreleasePoolObject final : EHScopeStack::Cleanup {
2878 llvm::Value *Token;
2879
2880 CallObjCAutoreleasePoolObject(llvm::Value *token) : Token(token) {}
2881
2882 void Emit(CodeGenFunction &CGF, Flags flags) override {
2883 CGF.EmitObjCAutoreleasePoolPop(Token);
2884 }
2885 };
2886 struct CallObjCMRRAutoreleasePoolObject final : EHScopeStack::Cleanup {
2887 llvm::Value *Token;
2888
2889 CallObjCMRRAutoreleasePoolObject(llvm::Value *token) : Token(token) {}
2890
2891 void Emit(CodeGenFunction &CGF, Flags flags) override {
2892 CGF.EmitObjCMRRAutoreleasePoolPop(Token);
2893 }
2894 };
2895}
2896
2897void CodeGenFunction::EmitObjCAutoreleasePoolCleanup(llvm::Value *Ptr) {
2898 if (CGM.getLangOpts().ObjCAutoRefCount)
2899 EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, Ptr);
2900 else
2901 EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, Ptr);
2902}
2903
2904static bool shouldRetainObjCLifetime(Qualifiers::ObjCLifetime lifetime) {
2905 switch (lifetime) {
2906 case Qualifiers::OCL_None:
2907 case Qualifiers::OCL_ExplicitNone:
2908 case Qualifiers::OCL_Strong:
2909 case Qualifiers::OCL_Autoreleasing:
2910 return true;
2911
2912 case Qualifiers::OCL_Weak:
2913 return false;
2914 }
2915
2916 llvm_unreachable("impossible lifetime!")::llvm::llvm_unreachable_internal("impossible lifetime!", "clang/lib/CodeGen/CGObjC.cpp"
, 2916)
;
2917}
2918
2919static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF,
2920 LValue lvalue,
2921 QualType type) {
2922 llvm::Value *result;
2923 bool shouldRetain = shouldRetainObjCLifetime(type.getObjCLifetime());
2924 if (shouldRetain) {
2925 result = CGF.EmitLoadOfLValue(lvalue, SourceLocation()).getScalarVal();
2926 } else {
2927 assert(type.getObjCLifetime() == Qualifiers::OCL_Weak)(static_cast <bool> (type.getObjCLifetime() == Qualifiers
::OCL_Weak) ? void (0) : __assert_fail ("type.getObjCLifetime() == Qualifiers::OCL_Weak"
, "clang/lib/CodeGen/CGObjC.cpp", 2927, __extension__ __PRETTY_FUNCTION__
))
;
2928 result = CGF.EmitARCLoadWeakRetained(lvalue.getAddress(CGF));
2929 }
2930 return TryEmitResult(result, !shouldRetain);
2931}
2932
2933static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF,
2934 const Expr *e) {
2935 e = e->IgnoreParens();
2936 QualType type = e->getType();
2937
2938 // If we're loading retained from a __strong xvalue, we can avoid
2939 // an extra retain/release pair by zeroing out the source of this
2940 // "move" operation.
2941 if (e->isXValue() &&
2942 !type.isConstQualified() &&
2943 type.getObjCLifetime() == Qualifiers::OCL_Strong) {
2944 // Emit the lvalue.
2945 LValue lv = CGF.EmitLValue(e);
2946
2947 // Load the object pointer.
2948 llvm::Value *result = CGF.EmitLoadOfLValue(lv,
2949 SourceLocation()).getScalarVal();
2950
2951 // Set the source pointer to NULL.
2952 CGF.EmitStoreOfScalar(getNullForVariable(lv.getAddress(CGF)), lv);
2953
2954 return TryEmitResult(result, true);
2955 }
2956
2957 // As a very special optimization, in ARC++, if the l-value is the
2958 // result of a non-volatile assignment, do a simple retain of the
2959 // result of the call to objc_storeWeak instead of reloading.
2960 if (CGF.getLangOpts().CPlusPlus &&
2961 !type.isVolatileQualified() &&
2962 type.getObjCLifetime() == Qualifiers::OCL_Weak &&
2963 isa<BinaryOperator>(e) &&
2964 cast<BinaryOperator>(e)->getOpcode() == BO_Assign)
2965 return TryEmitResult(CGF.EmitScalarExpr(e), false);
2966
2967 // Try to emit code for scalar constant instead of emitting LValue and
2968 // loading it because we are not guaranteed to have an l-value. One of such
2969 // cases is DeclRefExpr referencing non-odr-used constant-evaluated variable.
2970 if (const auto *decl_expr = dyn_cast<DeclRefExpr>(e)) {
2971 auto *DRE = const_cast<DeclRefExpr *>(decl_expr);
2972 if (CodeGenFunction::ConstantEmission constant = CGF.tryEmitAsConstant(DRE))
2973 return TryEmitResult(CGF.emitScalarConstant(constant, DRE),
2974 !shouldRetainObjCLifetime(type.getObjCLifetime()));
2975 }
2976
2977 return tryEmitARCRetainLoadOfScalar(CGF, CGF.EmitLValue(e), type);
2978}
2979
2980typedef llvm::function_ref<llvm::Value *(CodeGenFunction &CGF,
2981 llvm::Value *value)>
2982 ValueTransform;
2983
2984/// Insert code immediately after a call.
2985
2986// FIXME: We should find a way to emit the runtime call immediately
2987// after the call is emitted to eliminate the need for this function.
2988static llvm::Value *emitARCOperationAfterCall(CodeGenFunction &CGF,
2989 llvm::Value *value,
2990 ValueTransform doAfterCall,
2991 ValueTransform doFallback) {
2992 CGBuilderTy::InsertPoint ip = CGF.Builder.saveIP();
2993 auto *callBase = dyn_cast<llvm::CallBase>(value);
2994
2995 if (callBase && llvm::objcarc::hasAttachedCallOpBundle(callBase)) {
2996 // Fall back if the call base has operand bundle "clang.arc.attachedcall".
2997 value = doFallback(CGF, value);
2998 } else if (llvm::CallInst *call = dyn_cast<llvm::CallInst>(value)) {
2999 // Place the retain immediately following the call.
3000 CGF.Builder.SetInsertPoint(call->getParent(),
3001 ++llvm::BasicBlock::iterator(call));
3002 value = doAfterCall(CGF, value);
3003 } else if (llvm::InvokeInst *invoke = dyn_cast<llvm::InvokeInst>(value)) {
3004 // Place the retain at the beginning of the normal destination block.
3005 llvm::BasicBlock *BB = invoke->getNormalDest();
3006 CGF.Builder.SetInsertPoint(BB, BB->begin());
3007 value = doAfterCall(CGF, value);
3008
3009 // Bitcasts can arise because of related-result returns. Rewrite
3010 // the operand.
3011 } else if (llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(value)) {
3012 // Change the insert point to avoid emitting the fall-back call after the
3013 // bitcast.
3014 CGF.Builder.SetInsertPoint(bitcast->getParent(), bitcast->getIterator());
3015 llvm::Value *operand = bitcast->getOperand(0);
3016 operand = emitARCOperationAfterCall(CGF, operand, doAfterCall, doFallback);
3017 bitcast->setOperand(0, operand);
3018 value = bitcast;
3019 } else {
3020 auto *phi = dyn_cast<llvm::PHINode>(value);
3021 if (phi && phi->getNumIncomingValues() == 2 &&
3022 isa<llvm::ConstantPointerNull>(phi->getIncomingValue(1)) &&
3023 isa<llvm::CallBase>(phi->getIncomingValue(0))) {
3024 // Handle phi instructions that are generated when it's necessary to check
3025 // whether the receiver of a message is null.
3026 llvm::Value *inVal = phi->getIncomingValue(0);
3027 inVal = emitARCOperationAfterCall(CGF, inVal, doAfterCall, doFallback);
3028 phi->setIncomingValue(0, inVal);
3029 value = phi;
3030 } else {
3031 // Generic fall-back case.
3032 // Retain using the non-block variant: we never need to do a copy
3033 // of a block that's been returned to us.
3034 value = doFallback(CGF, value);
3035 }
3036 }
3037
3038 CGF.Builder.restoreIP(ip);
3039 return value;
3040}
3041
3042/// Given that the given expression is some sort of call (which does
3043/// not return retained), emit a retain following it.
3044static llvm::Value *emitARCRetainCallResult(CodeGenFunction &CGF,
3045 const Expr *e) {
3046 llvm::Value *value = CGF.EmitScalarExpr(e);
3047 return emitARCOperationAfterCall(CGF, value,
3048 [](CodeGenFunction &CGF, llvm::Value *value) {
3049 return CGF.EmitARCRetainAutoreleasedReturnValue(value);
3050 },
3051 [](CodeGenFunction &CGF, llvm::Value *value) {
3052 return CGF.EmitARCRetainNonBlock(value);
3053 });
3054}
3055
3056/// Given that the given expression is some sort of call (which does
3057/// not return retained), perform an unsafeClaim following it.
3058static llvm::Value *emitARCUnsafeClaimCallResult(CodeGenFunction &CGF,
3059 const Expr *e) {
3060 llvm::Value *value = CGF.EmitScalarExpr(e);
3061 return emitARCOperationAfterCall(CGF, value,
3062 [](CodeGenFunction &CGF, llvm::Value *value) {
3063 return CGF.EmitARCUnsafeClaimAutoreleasedReturnValue(value);
3064 },
3065 [](CodeGenFunction &CGF, llvm::Value *value) {
3066 return value;
3067 });
3068}
3069
3070llvm::Value *CodeGenFunction::EmitARCReclaimReturnedObject(const Expr *E,
3071 bool allowUnsafeClaim) {
3072 if (allowUnsafeClaim &&
3073 CGM.getLangOpts().ObjCRuntime.hasARCUnsafeClaimAutoreleasedReturnValue()) {
3074 return emitARCUnsafeClaimCallResult(*this, E);
3075 } else {
3076 llvm::Value *value = emitARCRetainCallResult(*this, E);
3077 return EmitObjCConsumeObject(E->getType(), value);
3078 }
3079}
3080
3081/// Determine whether it might be important to emit a separate
3082/// objc_retain_block on the result of the given expression, or
3083/// whether it's okay to just emit it in a +1 context.
3084static bool shouldEmitSeparateBlockRetain(const Expr *e) {
3085 assert(e->getType()->isBlockPointerType())(static_cast <bool> (e->getType()->isBlockPointerType
()) ? void (0) : __assert_fail ("e->getType()->isBlockPointerType()"
, "clang/lib/CodeGen/CGObjC.cpp", 3085, __extension__ __PRETTY_FUNCTION__
))
;
3086 e = e->IgnoreParens();
3087
3088 // For future goodness, emit block expressions directly in +1
3089 // contexts if we can.
3090 if (isa<BlockExpr>(e))
3091 return false;
3092
3093 if (const CastExpr *cast = dyn_cast<CastExpr>(e)) {
3094 switch (cast->getCastKind()) {
3095 // Emitting these operations in +1 contexts is goodness.
3096 case CK_LValueToRValue:
3097 case CK_ARCReclaimReturnedObject:
3098 case CK_ARCConsumeObject:
3099 case CK_ARCProduceObject:
3100 return false;
3101
3102 // These operations preserve a block type.
3103 case CK_NoOp:
3104 case CK_BitCast:
3105 return shouldEmitSeparateBlockRetain(cast->getSubExpr());
3106
3107 // These operations are known to be bad (or haven't been considered).
3108 case CK_AnyPointerToBlockPointerCast:
3109 default:
3110 return true;
3111 }
3112 }
3113
3114 return true;
3115}
3116
3117namespace {
3118/// A CRTP base class for emitting expressions of retainable object
3119/// pointer type in ARC.
3120template <typename Impl, typename Result> class ARCExprEmitter {
3121protected:
3122 CodeGenFunction &CGF;
3123 Impl &asImpl() { return *static_cast<Impl*>(this); }
3124
3125 ARCExprEmitter(CodeGenFunction &CGF) : CGF(CGF) {}
3126
3127public:
3128 Result visit(const Expr *e);
3129 Result visitCastExpr(const CastExpr *e);
3130 Result visitPseudoObjectExpr(const PseudoObjectExpr *e);
3131 Result visitBlockExpr(const BlockExpr *e);
3132 Result visitBinaryOperator(const BinaryOperator *e);
3133 Result visitBinAssign(const BinaryOperator *e);
3134 Result visitBinAssignUnsafeUnretained(const BinaryOperator *e);
3135 Result visitBinAssignAutoreleasing(const BinaryOperator *e);
3136 Result visitBinAssignWeak(const BinaryOperator *e);
3137 Result visitBinAssignStrong(const BinaryOperator *e);
3138
3139 // Minimal implementation:
3140 // Result visitLValueToRValue(const Expr *e)
3141 // Result visitConsumeObject(const Expr *e)
3142 // Result visitExtendBlockObject(const Expr *e)
3143 // Result visitReclaimReturnedObject(const Expr *e)
3144 // Result visitCall(const Expr *e)
3145 // Result visitExpr(const Expr *e)
3146 //
3147 // Result emitBitCast(Result result, llvm::Type *resultType)
3148 // llvm::Value *getValueOfResult(Result result)
3149};
3150}
3151
3152/// Try to emit a PseudoObjectExpr under special ARC rules.
3153///
3154/// This massively duplicates emitPseudoObjectRValue.
3155template <typename Impl, typename Result>
3156Result
3157ARCExprEmitter<Impl,Result>::visitPseudoObjectExpr(const PseudoObjectExpr *E) {
3158 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
3159
3160 // Find the result expression.
3161 const Expr *resultExpr = E->getResultExpr();
3162 assert(resultExpr)(static_cast <bool> (resultExpr) ? void (0) : __assert_fail
("resultExpr", "clang/lib/CodeGen/CGObjC.cpp", 3162, __extension__
__PRETTY_FUNCTION__))
;
18
Assuming 'resultExpr' is non-null
19
'?' condition is true
3163 Result result;
20
'result' declared without an initial value
3164
3165 for (PseudoObjectExpr::const_semantics_iterator
21
Loop condition is false. Execution continues on line 3201
3166 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
3167 const Expr *semantic = *i;
3168
3169 // If this semantic expression is an opaque value, bind it
3170 // to the result of its source expression.
3171 if (const OpaqueValueExpr *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
3172 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
3173 OVMA opaqueData;
3174
3175 // If this semantic is the result of the pseudo-object
3176 // expression, try to evaluate the source as +1.
3177 if (ov == resultExpr) {
3178 assert(!OVMA::shouldBindAsLValue(ov))(static_cast <bool> (!OVMA::shouldBindAsLValue(ov)) ? void
(0) : __assert_fail ("!OVMA::shouldBindAsLValue(ov)", "clang/lib/CodeGen/CGObjC.cpp"
, 3178, __extension__ __PRETTY_FUNCTION__))
;
3179 result = asImpl().visit(ov->getSourceExpr());
3180 opaqueData = OVMA::bind(CGF, ov,
3181 RValue::get(asImpl().getValueOfResult(result)));
3182
3183 // Otherwise, just bind it.
3184 } else {
3185 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
3186 }
3187 opaques.push_back(opaqueData);
3188
3189 // Otherwise, if the expression is the result, evaluate it
3190 // and remember the result.
3191 } else if (semantic == resultExpr) {
3192 result = asImpl().visit(semantic);
3193
3194 // Otherwise, evaluate the expression in an ignored context.
3195 } else {
3196 CGF.EmitIgnoredExpr(semantic);
3197 }
3198 }
3199
3200 // Unbind all the opaques now.
3201 for (unsigned i = 0, e = opaques.size(); i != e; ++i)
22
Assuming 'i' is equal to 'e'
23
Loop condition is false. Execution continues on line 3204
3202 opaques[i].unbind(CGF);
3203
3204 return result;
24
Undefined or garbage value returned to caller
3205}
3206
3207template <typename Impl, typename Result>
3208Result ARCExprEmitter<Impl, Result>::visitBlockExpr(const BlockExpr *e) {
3209 // The default implementation just forwards the expression to visitExpr.
3210 return asImpl().visitExpr(e);
3211}
3212
3213template <typename Impl, typename Result>
3214Result ARCExprEmitter<Impl,Result>::visitCastExpr(const CastExpr *e) {
3215 switch (e->getCastKind()) {
3216
3217 // No-op casts don't change the type, so we just ignore them.
3218 case CK_NoOp:
3219 return asImpl().visit(e->getSubExpr());
3220
3221 // These casts can change the type.
3222 case CK_CPointerToObjCPointerCast:
3223 case CK_BlockPointerToObjCPointerCast:
3224 case CK_AnyPointerToBlockPointerCast:
3225 case CK_BitCast: {
3226 llvm::Type *resultType = CGF.ConvertType(e->getType());
3227 assert(e->getSubExpr()->getType()->hasPointerRepresentation())(static_cast <bool> (e->getSubExpr()->getType()->
hasPointerRepresentation()) ? void (0) : __assert_fail ("e->getSubExpr()->getType()->hasPointerRepresentation()"
, "clang/lib/CodeGen/CGObjC.cpp", 3227, __extension__ __PRETTY_FUNCTION__
))
;
3228 Result result = asImpl().visit(e->getSubExpr());
3229 return asImpl().emitBitCast(result, resultType);
3230 }
3231
3232 // Handle some casts specially.
3233 case CK_LValueToRValue:
3234 return asImpl().visitLValueToRValue(e->getSubExpr());
3235 case CK_ARCConsumeObject:
3236 return asImpl().visitConsumeObject(e->getSubExpr());
3237 case CK_ARCExtendBlockObject:
3238 return asImpl().visitExtendBlockObject(e->getSubExpr());
3239 case CK_ARCReclaimReturnedObject:
3240 return asImpl().visitReclaimReturnedObject(e->getSubExpr());
3241
3242 // Otherwise, use the default logic.
3243 default:
3244 return asImpl().visitExpr(e);
3245 }
3246}
3247
3248template <typename Impl, typename Result>
3249Result
3250ARCExprEmitter<Impl,Result>::visitBinaryOperator(const BinaryOperator *e) {
3251 switch (e->getOpcode()) {
3252 case BO_Comma:
3253 CGF.EmitIgnoredExpr(e->getLHS());
3254 CGF.EnsureInsertPoint();
3255 return asImpl().visit(e->getRHS());
3256
3257 case BO_Assign:
3258 return asImpl().visitBinAssign(e);
3259
3260 default:
3261 return asImpl().visitExpr(e);
3262 }
3263}
3264
3265template <typename Impl, typename Result>
3266Result ARCExprEmitter<Impl,Result>::visitBinAssign(const BinaryOperator *e) {
3267 switch (e->getLHS()->getType().getObjCLifetime()) {
3268 case Qualifiers::OCL_ExplicitNone:
3269 return asImpl().visitBinAssignUnsafeUnretained(e);
3270
3271 case Qualifiers::OCL_Weak:
3272 return asImpl().visitBinAssignWeak(e);
3273
3274 case Qualifiers::OCL_Autoreleasing:
3275 return asImpl().visitBinAssignAutoreleasing(e);
3276
3277 case Qualifiers::OCL_Strong:
3278 return asImpl().visitBinAssignStrong(e);
3279
3280 case Qualifiers::OCL_None:
3281 return asImpl().visitExpr(e);
3282 }
3283 llvm_unreachable("bad ObjC ownership qualifier")::llvm::llvm_unreachable_internal("bad ObjC ownership qualifier"
, "clang/lib/CodeGen/CGObjC.cpp", 3283)
;
3284}
3285
3286/// The default rule for __unsafe_unretained emits the RHS recursively,
3287/// stores into the unsafe variable, and propagates the result outward.
3288template <typename Impl, typename Result>
3289Result ARCExprEmitter<Impl,Result>::
3290 visitBinAssignUnsafeUnretained(const BinaryOperator *e) {
3291 // Recursively emit the RHS.
3292 // For __block safety, do this before emitting the LHS.
3293 Result result = asImpl().visit(e->getRHS());
3294
3295 // Perform the store.
3296 LValue lvalue =
3297 CGF.EmitCheckedLValue(e->getLHS(), CodeGenFunction::TCK_Store);
3298 CGF.EmitStoreThroughLValue(RValue::get(asImpl().getValueOfResult(result)),
3299 lvalue);
3300
3301 return result;
3302}
3303
3304template <typename Impl, typename Result>
3305Result
3306ARCExprEmitter<Impl,Result>::visitBinAssignAutoreleasing(const BinaryOperator *e) {
3307 return asImpl().visitExpr(e);
3308}
3309
3310template <typename Impl, typename Result>
3311Result
3312ARCExprEmitter<Impl,Result>::visitBinAssignWeak(const BinaryOperator *e) {
3313 return asImpl().visitExpr(e);
3314}
3315
3316template <typename Impl, typename Result>
3317Result
3318ARCExprEmitter<Impl,Result>::visitBinAssignStrong(const BinaryOperator *e) {
3319 return asImpl().visitExpr(e);
3320}
3321
3322/// The general expression-emission logic.
3323template <typename Impl, typename Result>
3324Result ARCExprEmitter<Impl,Result>::visit(const Expr *e) {
3325 // We should *never* see a nested full-expression here, because if
3326 // we fail to emit at +1, our caller must not retain after we close
3327 // out the full-expression. This isn't as important in the unsafe
3328 // emitter.
3329 assert(!isa<ExprWithCleanups>(e))(static_cast <bool> (!isa<ExprWithCleanups>(e)) ?
void (0) : __assert_fail ("!isa<ExprWithCleanups>(e)",
"clang/lib/CodeGen/CGObjC.cpp", 3329, __extension__ __PRETTY_FUNCTION__
))
;
8
'e' is not a 'ExprWithCleanups'
9
'?' condition is true
3330
3331 // Look through parens, __extension__, generic selection, etc.
3332 e = e->IgnoreParens();
3333
3334 // Handle certain kinds of casts.
3335 if (const CastExpr *ce
10.1
'ce' is null
= dyn_cast<CastExpr>(e)) {
10
Assuming 'e' is not a 'CastReturnType'
11
Taking false branch
3336 return asImpl().visitCastExpr(ce);
3337
3338 // Handle the comma operator.
3339 } else if (auto op
12.1
'op' is null
= dyn_cast<BinaryOperator>(e)) {
12
Assuming 'e' is not a 'CastReturnType'
3340 return asImpl().visitBinaryOperator(op);
3341
3342 // TODO: handle conditional operators here
3343
3344 // For calls and message sends, use the retained-call logic.
3345 // Delegate inits are a special case in that they're the only
3346 // returns-retained expression that *isn't* surrounded by
3347 // a consume.
3348 } else if (isa<CallExpr>(e) ||
13
Assuming 'e' is not a 'CallExpr'
3349 (isa<ObjCMessageExpr>(e) &&
14
Assuming 'e' is not a 'ObjCMessageExpr'
3350 !cast<ObjCMessageExpr>(e)->isDelegateInitCall())) {
3351 return asImpl().visitCall(e);
3352
3353 // Look through pseudo-object expressions.
3354 } else if (const PseudoObjectExpr *pseudo
15.1
'pseudo' is non-null
= dyn_cast<PseudoObjectExpr>(e)) {
15
Assuming 'e' is a 'CastReturnType'
16
Taking true branch
3355 return asImpl().visitPseudoObjectExpr(pseudo);
17
Calling 'ARCExprEmitter::visitPseudoObjectExpr'
3356 } else if (auto *be = dyn_cast<BlockExpr>(e))
3357 return asImpl().visitBlockExpr(be);
3358
3359 return asImpl().visitExpr(e);
3360}
3361
3362namespace {
3363
3364/// An emitter for +1 results.
3365struct ARCRetainExprEmitter :
3366 public ARCExprEmitter<ARCRetainExprEmitter, TryEmitResult> {
3367
3368 ARCRetainExprEmitter(CodeGenFunction &CGF) : ARCExprEmitter(CGF) {}
3369
3370 llvm::Value *getValueOfResult(TryEmitResult result) {
3371 return result.getPointer();
3372 }
3373
3374 TryEmitResult emitBitCast(TryEmitResult result, llvm::Type *resultType) {
3375 llvm::Value *value = result.getPointer();
3376 value = CGF.Builder.CreateBitCast(value, resultType);
3377 result.setPointer(value);
3378 return result;
3379 }
3380
3381 TryEmitResult visitLValueToRValue(const Expr *e) {
3382 return tryEmitARCRetainLoadOfScalar(CGF, e);
3383 }
3384
3385 /// For consumptions, just emit the subexpression and thus elide
3386 /// the retain/release pair.
3387 TryEmitResult visitConsumeObject(const Expr *e) {
3388 llvm::Value *result = CGF.EmitScalarExpr(e);
3389 return TryEmitResult(result, true);
3390 }
3391
3392 TryEmitResult visitBlockExpr(const BlockExpr *e) {
3393 TryEmitResult result = visitExpr(e);
3394 // Avoid the block-retain if this is a block literal that doesn't need to be
3395 // copied to the heap.
3396 if (CGF.CGM.getCodeGenOpts().ObjCAvoidHeapifyLocalBlocks &&
3397 e->getBlockDecl()->canAvoidCopyToHeap())
3398 result.setInt(true);
3399 return result;
3400 }
3401
3402 /// Block extends are net +0. Naively, we could just recurse on
3403 /// the subexpression, but actually we need to ensure that the
3404 /// value is copied as a block, so there's a little filter here.
3405 TryEmitResult visitExtendBlockObject(const Expr *e) {
3406 llvm::Value *result; // will be a +0 value
3407
3408 // If we can't safely assume the sub-expression will produce a
3409 // block-copied value, emit the sub-expression at +0.
3410 if (shouldEmitSeparateBlockRetain(e)) {
3411 result = CGF.EmitScalarExpr(e);
3412
3413 // Otherwise, try to emit the sub-expression at +1 recursively.
3414 } else {
3415 TryEmitResult subresult = asImpl().visit(e);
3416
3417 // If that produced a retained value, just use that.
3418 if (subresult.getInt()) {
3419 return subresult;
3420 }
3421
3422 // Otherwise it's +0.
3423 result = subresult.getPointer();
3424 }
3425
3426 // Retain the object as a block.
3427 result = CGF.EmitARCRetainBlock(result, /*mandatory*/ true);
3428 return TryEmitResult(result, true);
3429 }
3430
3431 /// For reclaims, emit the subexpression as a retained call and
3432 /// skip the consumption.
3433 TryEmitResult visitReclaimReturnedObject(const Expr *e) {
3434 llvm::Value *result = emitARCRetainCallResult(CGF, e);
3435 return TryEmitResult(result, true);
3436 }
3437
3438 /// When we have an undecorated call, retroactively do a claim.
3439 TryEmitResult visitCall(const Expr *e) {
3440 llvm::Value *result = emitARCRetainCallResult(CGF, e);
3441 return TryEmitResult(result, true);
3442 }
3443
3444 // TODO: maybe special-case visitBinAssignWeak?
3445
3446 TryEmitResult visitExpr(const Expr *e) {
3447 // We didn't find an obvious production, so emit what we've got and
3448 // tell the caller that we didn't manage to retain.
3449 llvm::Value *result = CGF.EmitScalarExpr(e);
3450 return TryEmitResult(result, false);
3451 }
3452};
3453}
3454
3455static TryEmitResult
3456tryEmitARCRetainScalarExpr(CodeGenFunction &CGF, const Expr *e) {
3457 return ARCRetainExprEmitter(CGF).visit(e);
3458}
3459
3460static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF,
3461 LValue lvalue,
3462 QualType type) {
3463 TryEmitResult result = tryEmitARCRetainLoadOfScalar(CGF, lvalue, type);
3464 llvm::Value *value = result.getPointer();
3465 if (!result.getInt())
3466 value = CGF.EmitARCRetain(type, value);
3467 return value;
3468}
3469
3470/// EmitARCRetainScalarExpr - Semantically equivalent to
3471/// EmitARCRetainObject(e->getType(), EmitScalarExpr(e)), but making a
3472/// best-effort attempt to peephole expressions that naturally produce
3473/// retained objects.
3474llvm::Value *CodeGenFunction::EmitARCRetainScalarExpr(const Expr *e) {
3475 // The retain needs to happen within the full-expression.
3476 if (const ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(e)) {
3477 RunCleanupsScope scope(*this);
3478 return EmitARCRetainScalarExpr(cleanups->getSubExpr());
3479 }
3480
3481 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e);
3482 llvm::Value *value = result.getPointer();
3483 if (!result.getInt())
3484 value = EmitARCRetain(e->getType(), value);
3485 return value;
3486}
3487
3488llvm::Value *
3489CodeGenFunction::EmitARCRetainAutoreleaseScalarExpr(const Expr *e) {
3490 // The retain needs to happen within the full-expression.
3491 if (const ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(e)) {
3492 RunCleanupsScope scope(*this);
3493 return EmitARCRetainAutoreleaseScalarExpr(cleanups->getSubExpr());
3494 }
3495
3496 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e);
3497 llvm::Value *value = result.getPointer();
3498 if (result.getInt())
3499 value = EmitARCAutorelease(value);
3500 else
3501 value = EmitARCRetainAutorelease(e->getType(), value);
3502 return value;
3503}
3504
3505llvm::Value *CodeGenFunction::EmitARCExtendBlockObject(const Expr *e) {
3506 llvm::Value *result;
3507 bool doRetain;
3508
3509 if (shouldEmitSeparateBlockRetain(e)) {
3510 result = EmitScalarExpr(e);
3511 doRetain = true;
3512 } else {
3513 TryEmitResult subresult = tryEmitARCRetainScalarExpr(*this, e);
3514 result = subresult.getPointer();
3515 doRetain = !subresult.getInt();
3516 }
3517
3518 if (doRetain)
3519 result = EmitARCRetainBlock(result, /*mandatory*/ true);
3520 return EmitObjCConsumeObject(e->getType(), result);
3521}
3522
3523llvm::Value *CodeGenFunction::EmitObjCThrowOperand(const Expr *expr) {
3524 // In ARC, retain and autorelease the expression.
3525 if (getLangOpts().ObjCAutoRefCount) {
3526 // Do so before running any cleanups for the full-expression.
3527 // EmitARCRetainAutoreleaseScalarExpr does this for us.
3528 return EmitARCRetainAutoreleaseScalarExpr(expr);
3529 }
3530
3531 // Otherwise, use the normal scalar-expression emission. The
3532 // exception machinery doesn't do anything special with the
3533 // exception like retaining it, so there's no safety associated with
3534 // only running cleanups after the throw has started, and when it
3535 // matters it tends to be substantially inferior code.
3536 return EmitScalarExpr(expr);
3537}
3538
3539namespace {
3540
3541/// An emitter for assigning into an __unsafe_unretained context.
3542struct ARCUnsafeUnretainedExprEmitter :
3543 public ARCExprEmitter<ARCUnsafeUnretainedExprEmitter, llvm::Value*> {
3544
3545 ARCUnsafeUnretainedExprEmitter(CodeGenFunction &CGF) : ARCExprEmitter(CGF) {}
3546
3547 llvm::Value *getValueOfResult(llvm::Value *value) {
3548 return value;
3549 }
3550
3551 llvm::Value *emitBitCast(llvm::Value *value, llvm::Type *resultType) {
3552 return CGF.Builder.CreateBitCast(value, resultType);
3553 }
3554
3555 llvm::Value *visitLValueToRValue(const Expr *e) {
3556 return CGF.EmitScalarExpr(e);
3557 }
3558
3559 /// For consumptions, just emit the subexpression and perform the
3560 /// consumption like normal.
3561 llvm::Value *visitConsumeObject(const Expr *e) {
3562 llvm::Value *value = CGF.EmitScalarExpr(e);
3563 return CGF.EmitObjCConsumeObject(e->getType(), value);
3564 }
3565
3566 /// No special logic for block extensions. (This probably can't
3567 /// actually happen in this emitter, though.)
3568 llvm::Value *visitExtendBlockObject(const Expr *e) {
3569 return CGF.EmitARCExtendBlockObject(e);
3570 }
3571
3572 /// For reclaims, perform an unsafeClaim if that's enabled.
3573 llvm::Value *visitReclaimReturnedObject(const Expr *e) {
3574 return CGF.EmitARCReclaimReturnedObject(e, /*unsafe*/ true);
3575 }
3576
3577 /// When we have an undecorated call, just emit it without adding
3578 /// the unsafeClaim.
3579 llvm::Value *visitCall(const Expr *e) {
3580 return CGF.EmitScalarExpr(e);
3581 }
3582
3583 /// Just do normal scalar emission in the default case.
3584 llvm::Value *visitExpr(const Expr *e) {
3585 return CGF.EmitScalarExpr(e);
3586 }
3587};
3588}
3589
3590static llvm::Value *emitARCUnsafeUnretainedScalarExpr(CodeGenFunction &CGF,
3591 const Expr *e) {
3592 return ARCUnsafeUnretainedExprEmitter(CGF).visit(e);
7
Calling 'ARCExprEmitter::visit'
3593}
3594
3595/// EmitARCUnsafeUnretainedScalarExpr - Semantically equivalent to
3596/// immediately releasing the resut of EmitARCRetainScalarExpr, but
3597/// avoiding any spurious retains, including by performing reclaims
3598/// with objc_unsafeClaimAutoreleasedReturnValue.
3599llvm::Value *CodeGenFunction::EmitARCUnsafeUnretainedScalarExpr(const Expr *e) {
3600 // Look through full-expressions.
3601 if (const ExprWithCleanups *cleanups
4.1
'cleanups' is null
= dyn_cast<ExprWithCleanups>(e)) {
4
Assuming 'e' is not a 'CastReturnType'
5
Taking false branch
3602 RunCleanupsScope scope(*this);
3603 return emitARCUnsafeUnretainedScalarExpr(*this, cleanups->getSubExpr());
3604 }
3605
3606 return emitARCUnsafeUnretainedScalarExpr(*this, e);
6
Calling 'emitARCUnsafeUnretainedScalarExpr'
3607}
3608
3609std::pair<LValue,llvm::Value*>
3610CodeGenFunction::EmitARCStoreUnsafeUnretained(const BinaryOperator *e,
3611 bool ignored) {
3612 // Evaluate the RHS first. If we're ignoring the result, assume
3613 // that we can emit at an unsafe +0.
3614 llvm::Value *value;
3615 if (ignored) {
1
Assuming 'ignored' is true
2
Taking true branch
3616 value = EmitARCUnsafeUnretainedScalarExpr(e->getRHS());
3
Calling 'CodeGenFunction::EmitARCUnsafeUnretainedScalarExpr'
3617 } else {
3618 value = EmitScalarExpr(e->getRHS());
3619 }
3620
3621 // Emit the LHS and perform the store.
3622 LValue lvalue = EmitLValue(e->getLHS());
3623 EmitStoreOfScalar(value, lvalue);
3624
3625 return std::pair<LValue,llvm::Value*>(std::move(lvalue), value);
3626}
3627
3628std::pair<LValue,llvm::Value*>
3629CodeGenFunction::EmitARCStoreStrong(const BinaryOperator *e,
3630 bool ignored) {
3631 // Evaluate the RHS first.
3632 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e->getRHS());
3633 llvm::Value *value = result.getPointer();
3634
3635 bool hasImmediateRetain = result.getInt();
3636
3637 // If we didn't emit a retained object, and the l-value is of block
3638 // type, then we need to emit the block-retain immediately in case
3639 // it invalidates the l-value.
3640 if (!hasImmediateRetain && e->getType()->isBlockPointerType()) {
3641 value = EmitARCRetainBlock(value, /*mandatory*/ false);
3642 hasImmediateRetain = true;
3643 }
3644
3645 LValue lvalue = EmitLValue(e->getLHS());
3646
3647 // If the RHS was emitted retained, expand this.
3648 if (hasImmediateRetain) {
3649 llvm::Value *oldValue = EmitLoadOfScalar(lvalue, SourceLocation());
3650 EmitStoreOfScalar(value, lvalue);
3651 EmitARCRelease(oldValue, lvalue.isARCPreciseLifetime());
3652 } else {
3653 value = EmitARCStoreStrong(lvalue, value, ignored);
3654 }
3655
3656 return std::pair<LValue,llvm::Value*>(lvalue, value);
3657}
3658
3659std::pair<LValue,llvm::Value*>
3660CodeGenFunction::EmitARCStoreAutoreleasing(const BinaryOperator *e) {
3661 llvm::Value *value = EmitARCRetainAutoreleaseScalarExpr(e->getRHS());
3662 LValue lvalue = EmitLValue(e->getLHS());
3663
3664 EmitStoreOfScalar(value, lvalue);
3665
3666 return std::pair<LValue,llvm::Value*>(lvalue, value);
3667}
3668
3669void CodeGenFunction::EmitObjCAutoreleasePoolStmt(
3670 const ObjCAutoreleasePoolStmt &ARPS) {
3671 const Stmt *subStmt = ARPS.getSubStmt();
3672 const CompoundStmt &S = cast<CompoundStmt>(*subStmt);
3673
3674 CGDebugInfo *DI = getDebugInfo();
3675 if (DI)
3676 DI->EmitLexicalBlockStart(Builder, S.getLBracLoc());
3677
3678 // Keep track of the current cleanup stack depth.
3679 RunCleanupsScope Scope(*this);
3680 if (CGM.getLangOpts().ObjCRuntime.hasNativeARC()) {
3681 llvm::Value *token = EmitObjCAutoreleasePoolPush();
3682 EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, token);
3683 } else {
3684 llvm::Value *token = EmitObjCMRRAutoreleasePoolPush();
3685 EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, token);
3686 }
3687
3688 for (const auto *I : S.body())
3689 EmitStmt(I);
3690
3691 if (DI)
3692 DI->EmitLexicalBlockEnd(Builder, S.getRBracLoc());
3693}
3694
3695/// EmitExtendGCLifetime - Given a pointer to an Objective-C object,
3696/// make sure it survives garbage collection until this point.
3697void CodeGenFunction::EmitExtendGCLifetime(llvm::Value *object) {
3698 // We just use an inline assembly.
3699 llvm::FunctionType *extenderType
3700 = llvm::FunctionType::get(VoidTy, VoidPtrTy, RequiredArgs::All);
3701 llvm::InlineAsm *extender = llvm::InlineAsm::get(extenderType,
3702 /* assembly */ "",
3703 /* constraints */ "r",
3704 /* side effects */ true);
3705
3706 object = Builder.CreateBitCast(object, VoidPtrTy);
3707 EmitNounwindRuntimeCall(extender, object);
3708}
3709
3710/// GenerateObjCAtomicSetterCopyHelperFunction - Given a c++ object type with
3711/// non-trivial copy assignment function, produce following helper function.
3712/// static void copyHelper(Ty *dest, const Ty *source) { *dest = *source; }
3713///
3714llvm::Constant *
3715CodeGenFunction::GenerateObjCAtomicSetterCopyHelperFunction(
3716 const ObjCPropertyImplDecl *PID) {
3717 const ObjCPropertyDecl *PD = PID->getPropertyDecl();
3718 if ((!(PD->getPropertyAttributes() & ObjCPropertyAttribute::kind_atomic)))
3719 return nullptr;
3720
3721 QualType Ty = PID->getPropertyIvarDecl()->getType();
3722 ASTContext &C = getContext();
3723
3724 if (Ty.isNonTrivialToPrimitiveCopy() == QualType::PCK_Struct) {
3725 // Call the move assignment operator instead of calling the copy assignment
3726 // operator and destructor.
3727 CharUnits Alignment = C.getTypeAlignInChars(Ty);
3728 llvm::Constant *Fn = getNonTrivialCStructMoveAssignmentOperator(
3729 CGM, Alignment, Alignment, Ty.isVolatileQualified(), Ty);
3730 return llvm::ConstantExpr::getBitCast(Fn, VoidPtrTy);
3731 }
3732
3733 if (!getLangOpts().CPlusPlus ||
3734 !getLangOpts().ObjCRuntime.hasAtomicCopyHelper())
3735 return nullptr;
3736 if (!Ty->isRecordType())
3737 return nullptr;
3738 llvm::Constant *HelperFn = nullptr;
3739 if (hasTrivialSetExpr(PID))
3740 return nullptr;
3741 assert(PID->getSetterCXXAssignment() && "SetterCXXAssignment - null")(static_cast <bool> (PID->getSetterCXXAssignment() &&
"SetterCXXAssignment - null") ? void (0) : __assert_fail ("PID->getSetterCXXAssignment() && \"SetterCXXAssignment - null\""
, "clang/lib/CodeGen/CGObjC.cpp", 3741, __extension__ __PRETTY_FUNCTION__
))
;
3742 if ((HelperFn = CGM.getAtomicSetterHelperFnMap(Ty)))
3743 return HelperFn;
3744
3745 IdentifierInfo *II
3746 = &CGM.getContext().Idents.get("__assign_helper_atomic_property_");
3747
3748 QualType ReturnTy = C.VoidTy;
3749 QualType DestTy = C.getPointerType(Ty);
3750 QualType SrcTy = Ty;
3751 SrcTy.addConst();
3752 SrcTy = C.getPointerType(SrcTy);
3753
3754 SmallVector<QualType, 2> ArgTys;
3755 ArgTys.push_back(DestTy);
3756 ArgTys.push_back(SrcTy);
3757 QualType FunctionTy = C.getFunctionType(ReturnTy, ArgTys, {});
3758
3759 FunctionDecl *FD = FunctionDecl::Create(
3760 C, C.getTranslationUnitDecl(), SourceLocation(), SourceLocation(), II,
3761 FunctionTy, nullptr, SC_Static, false, false, false);
3762
3763 FunctionArgList args;
3764 ParmVarDecl *Params[2];
3765 ParmVarDecl *DstDecl = ParmVarDecl::Create(
3766 C, FD, SourceLocation(), SourceLocation(), nullptr, DestTy,
3767 C.getTrivialTypeSourceInfo(DestTy, SourceLocation()), SC_None,
3768 /*DefArg=*/nullptr);
3769 args.push_back(Params[0] = DstDecl);
3770 ParmVarDecl *SrcDecl = ParmVarDecl::Create(
3771 C, FD, SourceLocation(), SourceLocation(), nullptr, SrcTy,
3772 C.getTrivialTypeSourceInfo(SrcTy, SourceLocation()), SC_None,
3773 /*DefArg=*/nullptr);
3774 args.push_back(Params[1] = SrcDecl);
3775 FD->setParams(Params);
3776
3777 const CGFunctionInfo &FI =
3778 CGM.getTypes().arrangeBuiltinFunctionDeclaration(ReturnTy, args);
3779
3780 llvm::FunctionType *LTy = CGM.getTypes().GetFunctionType(FI);
3781
3782 llvm::Function *Fn =
3783 llvm::Function::Create(LTy, llvm::GlobalValue::InternalLinkage,
3784 "__assign_helper_atomic_property_",
3785 &CGM.getModule());
3786
3787 CGM.SetInternalFunctionAttributes(GlobalDecl(), Fn, FI);
3788
3789 StartFunction(FD, ReturnTy, Fn, FI, args);
3790
3791 DeclRefExpr DstExpr(C, DstDecl, false, DestTy, VK_PRValue, SourceLocation());
3792 UnaryOperator *DST = UnaryOperator::Create(
3793 C, &DstExpr, UO_Deref, DestTy->getPointeeType(), VK_LValue, OK_Ordinary,
3794 SourceLocation(), false, FPOptionsOverride());
3795
3796 DeclRefExpr SrcExpr(C, SrcDecl, false, SrcTy, VK_PRValue, SourceLocation());
3797 UnaryOperator *SRC = UnaryOperator::Create(
3798 C, &SrcExpr, UO_Deref, SrcTy->getPointeeType(), VK_LValue, OK_Ordinary,
3799 SourceLocation(), false, FPOptionsOverride());
3800
3801 Expr *Args[2] = {DST, SRC};
3802 CallExpr *CalleeExp = cast<CallExpr>(PID->getSetterCXXAssignment());
3803 CXXOperatorCallExpr *TheCall = CXXOperatorCallExpr::Create(
3804 C, OO_Equal, CalleeExp->getCallee(), Args, DestTy->getPointeeType(),
3805 VK_LValue, SourceLocation(), FPOptionsOverride());
3806
3807 EmitStmt(TheCall);
3808
3809 FinishFunction();
3810 HelperFn = llvm::ConstantExpr::getBitCast(Fn, VoidPtrTy);
3811 CGM.setAtomicSetterHelperFnMap(Ty, HelperFn);
3812 return HelperFn;
3813}
3814
3815llvm::Constant *CodeGenFunction::GenerateObjCAtomicGetterCopyHelperFunction(
3816 const ObjCPropertyImplDecl *PID) {
3817 const ObjCPropertyDecl *PD = PID->getPropertyDecl();
3818 if ((!(PD->getPropertyAttributes() & ObjCPropertyAttribute::kind_atomic)))
3819 return nullptr;
3820
3821 QualType Ty = PD->getType();
3822 ASTContext &C = getContext();
3823
3824 if (Ty.isNonTrivialToPrimitiveCopy() == QualType::PCK_Struct) {
3825 CharUnits Alignment = C.getTypeAlignInChars(Ty);
3826 llvm::Constant *Fn = getNonTrivialCStructCopyConstructor(
3827 CGM, Alignment, Alignment, Ty.isVolatileQualified(), Ty);
3828 return llvm::ConstantExpr::getBitCast(Fn, VoidPtrTy);
3829 }
3830
3831 if (!getLangOpts().CPlusPlus ||
3832 !getLangOpts().ObjCRuntime.hasAtomicCopyHelper())
3833 return nullptr;
3834 if (!Ty->isRecordType())
3835 return nullptr;
3836 llvm::Constant *HelperFn = nullptr;
3837 if (hasTrivialGetExpr(PID))
3838 return nullptr;
3839 assert(PID->getGetterCXXConstructor() && "getGetterCXXConstructor - null")(static_cast <bool> (PID->getGetterCXXConstructor() &&
"getGetterCXXConstructor - null") ? void (0) : __assert_fail
("PID->getGetterCXXConstructor() && \"getGetterCXXConstructor - null\""
, "clang/lib/CodeGen/CGObjC.cpp", 3839, __extension__ __PRETTY_FUNCTION__
))
;
3840 if ((HelperFn = CGM.getAtomicGetterHelperFnMap(Ty)))
3841 return HelperFn;
3842
3843 IdentifierInfo *II =
3844 &CGM.getContext().Idents.get("__copy_helper_atomic_property_");
3845
3846 QualType ReturnTy = C.VoidTy;
3847 QualType DestTy = C.getPointerType(Ty);
3848 QualType SrcTy = Ty;
3849 SrcTy.addConst();
3850 SrcTy = C.getPointerType(SrcTy);
3851
3852 SmallVector<QualType, 2> ArgTys;
3853 ArgTys.push_back(DestTy);
3854 ArgTys.push_back(SrcTy);
3855 QualType FunctionTy = C.getFunctionType(ReturnTy, ArgTys, {});
3856
3857 FunctionDecl *FD = FunctionDecl::Create(
3858 C, C.getTranslationUnitDecl(), SourceLocation(), SourceLocation(), II,
3859 FunctionTy, nullptr, SC_Static, false, false, false);
3860
3861 FunctionArgList args;
3862 ParmVarDecl *Params[2];
3863 ParmVarDecl *DstDecl = ParmVarDecl::Create(
3864 C, FD, SourceLocation(), SourceLocation(), nullptr, DestTy,
3865 C.getTrivialTypeSourceInfo(DestTy, SourceLocation()), SC_None,
3866 /*DefArg=*/nullptr);
3867 args.push_back(Params[0] = DstDecl);
3868 ParmVarDecl *SrcDecl = ParmVarDecl::Create(
3869 C, FD, SourceLocation(), SourceLocation(), nullptr, SrcTy,
3870 C.getTrivialTypeSourceInfo(SrcTy, SourceLocation()), SC_None,
3871 /*DefArg=*/nullptr);
3872 args.push_back(Params[1] = SrcDecl);
3873 FD->setParams(Params);
3874
3875 const CGFunctionInfo &FI =
3876 CGM.getTypes().arrangeBuiltinFunctionDeclaration(ReturnTy, args);
3877
3878 llvm::FunctionType *LTy = CGM.getTypes().GetFunctionType(FI);
3879
3880 llvm::Function *Fn = llvm::Function::Create(
3881 LTy, llvm::GlobalValue::InternalLinkage, "__copy_helper_atomic_property_",
3882 &CGM.getModule());
3883
3884 CGM.SetInternalFunctionAttributes(GlobalDecl(), Fn, FI);
3885
3886 StartFunction(FD, ReturnTy, Fn, FI, args);
3887
3888 DeclRefExpr SrcExpr(getContext(), SrcDecl, false, SrcTy, VK_PRValue,
3889 SourceLocation());
3890
3891 UnaryOperator *SRC = UnaryOperator::Create(
3892 C, &SrcExpr, UO_Deref, SrcTy->getPointeeType(), VK_LValue, OK_Ordinary,
3893 SourceLocation(), false, FPOptionsOverride());
3894
3895 CXXConstructExpr *CXXConstExpr =
3896 cast<CXXConstructExpr>(PID->getGetterCXXConstructor());
3897
3898 SmallVector<Expr*, 4> ConstructorArgs;
3899 ConstructorArgs.push_back(SRC);
3900 ConstructorArgs.append(std::next(CXXConstExpr->arg_begin()),
3901 CXXConstExpr->arg_end());
3902
3903 CXXConstructExpr *TheCXXConstructExpr =
3904 CXXConstructExpr::Create(C, Ty, SourceLocation(),
3905 CXXConstExpr->getConstructor(),
3906 CXXConstExpr->isElidable(),
3907 ConstructorArgs,
3908 CXXConstExpr->hadMultipleCandidates(),
3909 CXXConstExpr->isListInitialization(),
3910 CXXConstExpr->isStdInitListInitialization(),
3911 CXXConstExpr->requiresZeroInitialization(),
3912 CXXConstExpr->getConstructionKind(),
3913 SourceRange());
3914
3915 DeclRefExpr DstExpr(getContext(), DstDecl, false, DestTy, VK_PRValue,
3916 SourceLocation());
3917
3918 RValue DV = EmitAnyExpr(&DstExpr);
3919 CharUnits Alignment =
3920 getContext().getTypeAlignInChars(TheCXXConstructExpr->getType());
3921 EmitAggExpr(TheCXXConstructExpr,
3922 AggValueSlot::forAddr(
3923 Address(DV.getScalarVal(), ConvertTypeForMem(Ty), Alignment),
3924 Qualifiers(), AggValueSlot::IsDestructed,
3925 AggValueSlot::DoesNotNeedGCBarriers,
3926 AggValueSlot::IsNotAliased, AggValueSlot::DoesNotOverlap));
3927
3928 FinishFunction();
3929 HelperFn = llvm::ConstantExpr::getBitCast(Fn, VoidPtrTy);
3930 CGM.setAtomicGetterHelperFnMap(Ty, HelperFn);
3931 return HelperFn;
3932}
3933
3934llvm::Value *
3935CodeGenFunction::EmitBlockCopyAndAutorelease(llvm::Value *Block, QualType Ty) {
3936 // Get selectors for retain/autorelease.
3937 IdentifierInfo *CopyID = &getContext().Idents.get("copy");
3938 Selector CopySelector =
3939 getContext().Selectors.getNullarySelector(CopyID);
3940 IdentifierInfo *AutoreleaseID = &getContext().Idents.get("autorelease");
3941 Selector AutoreleaseSelector =
3942 getContext().Selectors.getNullarySelector(AutoreleaseID);
3943
3944 // Emit calls to retain/autorelease.
3945 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
3946 llvm::Value *Val = Block;
3947 RValue Result;
3948 Result = Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
3949 Ty, CopySelector,
3950 Val, CallArgList(), nullptr, nullptr);
3951 Val = Result.getScalarVal();
3952 Result = Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
3953 Ty, AutoreleaseSelector,
3954 Val, CallArgList(), nullptr, nullptr);
3955 Val = Result.getScalarVal();
3956 return Val;
3957}
3958
3959static unsigned getBaseMachOPlatformID(const llvm::Triple &TT) {
3960 switch (TT.getOS()) {
3961 case llvm::Triple::Darwin:
3962 case llvm::Triple::MacOSX:
3963 return llvm::MachO::PLATFORM_MACOS;
3964 case llvm::Triple::IOS:
3965 return llvm::MachO::PLATFORM_IOS;
3966 case llvm::Triple::TvOS:
3967 return llvm::MachO::PLATFORM_TVOS;
3968 case llvm::Triple::WatchOS:
3969 return llvm::MachO::PLATFORM_WATCHOS;
3970 case llvm::Triple::DriverKit:
3971 return llvm::MachO::PLATFORM_DRIVERKIT;
3972 default:
3973 return /*Unknown platform*/ 0;
3974 }
3975}
3976
3977static llvm::Value *emitIsPlatformVersionAtLeast(CodeGenFunction &CGF,
3978 const VersionTuple &Version) {
3979 CodeGenModule &CGM = CGF.CGM;
3980 // Note: we intend to support multi-platform version checks, so reserve
3981 // the room for a dual platform checking invocation that will be
3982 // implemented in the future.
3983 llvm::SmallVector<llvm::Value *, 8> Args;
3984
3985 auto EmitArgs = [&](const VersionTuple &Version, const llvm::Triple &TT) {
3986 std::optional<unsigned> Min = Version.getMinor(),
3987 SMin = Version.getSubminor();
3988 Args.push_back(
3989 llvm::ConstantInt::get(CGM.Int32Ty, getBaseMachOPlatformID(TT)));
3990 Args.push_back(llvm::ConstantInt::get(CGM.Int32Ty, Version.getMajor()));
3991 Args.push_back(llvm::ConstantInt::get(CGM.Int32Ty, Min.value_or(0)));
3992 Args.push_back(llvm::ConstantInt::get(CGM.Int32Ty, SMin.value_or(0)));
3993 };
3994
3995 assert(!Version.empty() && "unexpected empty version")(static_cast <bool> (!Version.empty() && "unexpected empty version"
) ? void (0) : __assert_fail ("!Version.empty() && \"unexpected empty version\""
, "clang/lib/CodeGen/CGObjC.cpp", 3995, __extension__ __PRETTY_FUNCTION__
))
;
3996 EmitArgs(Version, CGM.getTarget().getTriple());
3997
3998 if (!CGM.IsPlatformVersionAtLeastFn) {
3999 llvm::FunctionType *FTy = llvm::FunctionType::get(
4000 CGM.Int32Ty, {CGM.Int32Ty, CGM.Int32Ty, CGM.Int32Ty, CGM.Int32Ty},
4001 false);
4002 CGM.IsPlatformVersionAtLeastFn =
4003 CGM.CreateRuntimeFunction(FTy, "__isPlatformVersionAtLeast");
4004 }
4005
4006 llvm::Value *Check =
4007 CGF.EmitNounwindRuntimeCall(CGM.IsPlatformVersionAtLeastFn, Args);
4008 return CGF.Builder.CreateICmpNE(Check,
4009 llvm::Constant::getNullValue(CGM.Int32Ty));
4010}
4011
4012llvm::Value *
4013CodeGenFunction::EmitBuiltinAvailable(const VersionTuple &Version) {
4014 // Darwin uses the new __isPlatformVersionAtLeast family of routines.
4015 if (CGM.getTarget().getTriple().isOSDarwin())
4016 return emitIsPlatformVersionAtLeast(*this, Version);
4017
4018 if (!CGM.IsOSVersionAtLeastFn) {
4019 llvm::FunctionType *FTy =
4020 llvm::FunctionType::get(Int32Ty, {Int32Ty, Int32Ty, Int32Ty}, false);
4021 CGM.IsOSVersionAtLeastFn =
4022 CGM.CreateRuntimeFunction(FTy, "__isOSVersionAtLeast");
4023 }
4024
4025 std::optional<unsigned> Min = Version.getMinor(),
4026 SMin = Version.getSubminor();
4027 llvm::Value *Args[] = {
4028 llvm::ConstantInt::get(CGM.Int32Ty, Version.getMajor()),
4029 llvm::ConstantInt::get(CGM.Int32Ty, Min.value_or(0)),
4030 llvm::ConstantInt::get(CGM.Int32Ty, SMin.value_or(0))};
4031
4032 llvm::Value *CallRes =
4033 EmitNounwindRuntimeCall(CGM.IsOSVersionAtLeastFn, Args);
4034
4035 return Builder.CreateICmpNE(CallRes, llvm::Constant::getNullValue(Int32Ty));
4036}
4037
4038static bool isFoundationNeededForDarwinAvailabilityCheck(
4039 const llvm::Triple &TT, const VersionTuple &TargetVersion) {
4040 VersionTuple FoundationDroppedInVersion;
4041 switch (TT.getOS()) {
4042 case llvm::Triple::IOS:
4043 case llvm::Triple::TvOS:
4044 FoundationDroppedInVersion = VersionTuple(/*Major=*/13);
4045 break;
4046 case llvm::Triple::WatchOS:
4047 FoundationDroppedInVersion = VersionTuple(/*Major=*/6);
4048 break;
4049 case llvm::Triple::Darwin:
4050 case llvm::Triple::MacOSX:
4051 FoundationDroppedInVersion = VersionTuple(/*Major=*/10, /*Minor=*/15);
4052 break;
4053 case llvm::Triple::DriverKit:
4054 // DriverKit doesn't need Foundation.
4055 return false;
4056 default:
4057 llvm_unreachable("Unexpected OS")::llvm::llvm_unreachable_internal("Unexpected OS", "clang/lib/CodeGen/CGObjC.cpp"
, 4057)
;
4058 }
4059 return TargetVersion < FoundationDroppedInVersion;
4060}
4061
4062void CodeGenModule::emitAtAvailableLinkGuard() {
4063 if (!IsPlatformVersionAtLeastFn)
4064 return;
4065 // @available requires CoreFoundation only on Darwin.
4066 if (!Target.getTriple().isOSDarwin())
4067 return;
4068 // @available doesn't need Foundation on macOS 10.15+, iOS/tvOS 13+, or
4069 // watchOS 6+.
4070 if (!isFoundationNeededForDarwinAvailabilityCheck(
4071 Target.getTriple(), Target.getPlatformMinVersion()))
4072 return;
4073 // Add -framework CoreFoundation to the linker commands. We still want to
4074 // emit the core foundation reference down below because otherwise if
4075 // CoreFoundation is not used in the code, the linker won't link the
4076 // framework.
4077 auto &Context = getLLVMContext();
4078 llvm::Metadata *Args[2] = {llvm::MDString::get(Context, "-framework"),
4079 llvm::MDString::get(Context, "CoreFoundation")};
4080 LinkerOptionsMetadata.push_back(llvm::MDNode::get(Context, Args));
4081 // Emit a reference to a symbol from CoreFoundation to ensure that
4082 // CoreFoundation is linked into the final binary.
4083 llvm::FunctionType *FTy =
4084 llvm::FunctionType::get(Int32Ty, {VoidPtrTy}, false);
4085 llvm::FunctionCallee CFFunc =
4086 CreateRuntimeFunction(FTy, "CFBundleGetVersionNumber");
4087
4088 llvm::FunctionType *CheckFTy = llvm::FunctionType::get(VoidTy, {}, false);
4089 llvm::FunctionCallee CFLinkCheckFuncRef = CreateRuntimeFunction(
4090 CheckFTy, "__clang_at_available_requires_core_foundation_framework",
4091 llvm::AttributeList(), /*Local=*/true);
4092 llvm::Function *CFLinkCheckFunc =
4093 cast<llvm::Function>(CFLinkCheckFuncRef.getCallee()->stripPointerCasts());
4094 if (CFLinkCheckFunc->empty()) {
4095 CFLinkCheckFunc->setLinkage(llvm::GlobalValue::LinkOnceAnyLinkage);
4096 CFLinkCheckFunc->setVisibility(llvm::GlobalValue::HiddenVisibility);
4097 CodeGenFunction CGF(*this);
4098 CGF.Builder.SetInsertPoint(CGF.createBasicBlock("", CFLinkCheckFunc));
4099 CGF.EmitNounwindRuntimeCall(CFFunc,
4100 llvm::Constant::getNullValue(VoidPtrTy));
4101 CGF.Builder.CreateUnreachable();
4102 addCompilerUsedGlobal(CFLinkCheckFunc);
4103 }
4104}
4105
4106CGObjCRuntime::~CGObjCRuntime() {}