Bug Summary

File:build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/clang/lib/CodeGen/CGObjC.cpp
Warning:line 3151, 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/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/build-llvm -resource-dir /usr/lib/llvm-16/lib/clang/16.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I tools/clang/lib/CodeGen -I /build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/clang/lib/CodeGen -I /build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/clang/include -I tools/clang/include -I include -I /build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/llvm/include -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-16/lib/clang/16.0.0/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/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/build-llvm=build-llvm -fmacro-prefix-map=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/= -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/build-llvm=build-llvm -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/= -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/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/build-llvm -fdebug-prefix-map=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/build-llvm=build-llvm -fdebug-prefix-map=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/= -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-2022-09-04-125545-48738-1 -x c++ /build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/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 "llvm/ADT/STLExtras.h"
26#include "llvm/Analysis/ObjCARCUtil.h"
27#include "llvm/BinaryFormat/MachO.h"
28#include "llvm/IR/DataLayout.h"
29#include "llvm/IR/InlineAsm.h"
30using namespace clang;
31using namespace CodeGen;
32
33typedef llvm::PointerIntPair<llvm::Value*,1,bool> TryEmitResult;
34static TryEmitResult
35tryEmitARCRetainScalarExpr(CodeGenFunction &CGF, const Expr *e);
36static RValue AdjustObjCObjectType(CodeGenFunction &CGF,
37 QualType ET,
38 RValue Result);
39
40/// Given the address of a variable of pointer type, find the correct
41/// null to store into it.
42static llvm::Constant *getNullForVariable(Address addr) {
43 llvm::Type *type = addr.getElementType();
44 return llvm::ConstantPointerNull::get(cast<llvm::PointerType>(type));
45}
46
47/// Emits an instance of NSConstantString representing the object.
48llvm::Value *CodeGenFunction::EmitObjCStringLiteral(const ObjCStringLiteral *E)
49{
50 llvm::Constant *C =
51 CGM.getObjCRuntime().GenerateConstantString(E->getString()).getPointer();
52 // FIXME: This bitcast should just be made an invariant on the Runtime.
53 return llvm::ConstantExpr::getBitCast(C, ConvertType(E->getType()));
54}
55
56/// EmitObjCBoxedExpr - This routine generates code to call
57/// the appropriate expression boxing method. This will either be
58/// one of +[NSNumber numberWith<Type>:], or +[NSString stringWithUTF8String:],
59/// or [NSValue valueWithBytes:objCType:].
60///
61llvm::Value *
62CodeGenFunction::EmitObjCBoxedExpr(const ObjCBoxedExpr *E) {
63 // Generate the correct selector for this literal's concrete type.
64 // Get the method.
65 const ObjCMethodDecl *BoxingMethod = E->getBoxingMethod();
66 const Expr *SubExpr = E->getSubExpr();
67
68 if (E->isExpressibleAsConstantInitializer()) {
69 ConstantEmitter ConstEmitter(CGM);
70 return ConstEmitter.tryEmitAbstract(E, E->getType());
71 }
72
73 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", 73, __extension__ __PRETTY_FUNCTION__
))
;
74 Selector Sel = BoxingMethod->getSelector();
75
76 // Generate a reference to the class pointer, which will be the receiver.
77 // Assumes that the method was introduced in the class that should be
78 // messaged (avoids pulling it out of the result type).
79 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
80 const ObjCInterfaceDecl *ClassDecl = BoxingMethod->getClassInterface();
81 llvm::Value *Receiver = Runtime.GetClass(*this, ClassDecl);
82
83 CallArgList Args;
84 const ParmVarDecl *ArgDecl = *BoxingMethod->param_begin();
85 QualType ArgQT = ArgDecl->getType().getUnqualifiedType();
86
87 // ObjCBoxedExpr supports boxing of structs and unions
88 // via [NSValue valueWithBytes:objCType:]
89 const QualType ValueType(SubExpr->getType().getCanonicalType());
90 if (ValueType->isObjCBoxableRecordType()) {
91 // Emit CodeGen for first parameter
92 // and cast value to correct type
93 Address Temporary = CreateMemTemp(SubExpr->getType());
94 EmitAnyExprToMem(SubExpr, Temporary, Qualifiers(), /*isInit*/ true);
95 llvm::Value *BitCast =
96 Builder.CreateBitCast(Temporary.getPointer(), ConvertType(ArgQT));
97 Args.add(RValue::get(BitCast), ArgQT);
98
99 // Create char array to store type encoding
100 std::string Str;
101 getContext().getObjCEncodingForType(ValueType, Str);
102 llvm::Constant *GV = CGM.GetAddrOfConstantCString(Str).getPointer();
103
104 // Cast type encoding to correct type
105 const ParmVarDecl *EncodingDecl = BoxingMethod->parameters()[1];
106 QualType EncodingQT = EncodingDecl->getType().getUnqualifiedType();
107 llvm::Value *Cast = Builder.CreateBitCast(GV, ConvertType(EncodingQT));
108
109 Args.add(RValue::get(Cast), EncodingQT);
110 } else {
111 Args.add(EmitAnyExpr(SubExpr), ArgQT);
112 }
113
114 RValue result = Runtime.GenerateMessageSend(
115 *this, ReturnValueSlot(), BoxingMethod->getReturnType(), Sel, Receiver,
116 Args, ClassDecl, BoxingMethod);
117 return Builder.CreateBitCast(result.getScalarVal(),
118 ConvertType(E->getType()));
119}
120
121llvm::Value *CodeGenFunction::EmitObjCCollectionLiteral(const Expr *E,
122 const ObjCMethodDecl *MethodWithObjects) {
123 ASTContext &Context = CGM.getContext();
124 const ObjCDictionaryLiteral *DLE = nullptr;
125 const ObjCArrayLiteral *ALE = dyn_cast<ObjCArrayLiteral>(E);
126 if (!ALE)
127 DLE = cast<ObjCDictionaryLiteral>(E);
128
129 // Optimize empty collections by referencing constants, when available.
130 uint64_t NumElements =
131 ALE ? ALE->getNumElements() : DLE->getNumElements();
132 if (NumElements == 0 && CGM.getLangOpts().ObjCRuntime.hasEmptyCollections()) {
133 StringRef ConstantName = ALE ? "__NSArray0__" : "__NSDictionary0__";
134 QualType IdTy(CGM.getContext().getObjCIdType());
135 llvm::Constant *Constant =
136 CGM.CreateRuntimeVariable(ConvertType(IdTy), ConstantName);
137 LValue LV = MakeNaturalAlignAddrLValue(Constant, IdTy);
138 llvm::Value *Ptr = EmitLoadOfScalar(LV, E->getBeginLoc());
139 cast<llvm::LoadInst>(Ptr)->setMetadata(
140 CGM.getModule().getMDKindID("invariant.load"),
141 llvm::MDNode::get(getLLVMContext(), None));
142 return Builder.CreateBitCast(Ptr, ConvertType(E->getType()));
143 }
144
145 // Compute the type of the array we're initializing.
146 llvm::APInt APNumElements(Context.getTypeSize(Context.getSizeType()),
147 NumElements);
148 QualType ElementType = Context.getObjCIdType().withConst();
149 QualType ElementArrayType
150 = Context.getConstantArrayType(ElementType, APNumElements, nullptr,
151 ArrayType::Normal, /*IndexTypeQuals=*/0);
152
153 // Allocate the temporary array(s).
154 Address Objects = CreateMemTemp(ElementArrayType, "objects");
155 Address Keys = Address::invalid();
156 if (DLE)
157 Keys = CreateMemTemp(ElementArrayType, "keys");
158
159 // In ARC, we may need to do extra work to keep all the keys and
160 // values alive until after the call.
161 SmallVector<llvm::Value *, 16> NeededObjects;
162 bool TrackNeededObjects =
163 (getLangOpts().ObjCAutoRefCount &&
164 CGM.getCodeGenOpts().OptimizationLevel != 0);
165
166 // Perform the actual initialialization of the array(s).
167 for (uint64_t i = 0; i < NumElements; i++) {
168 if (ALE) {
169 // Emit the element and store it to the appropriate array slot.
170 const Expr *Rhs = ALE->getElement(i);
171 LValue LV = MakeAddrLValue(Builder.CreateConstArrayGEP(Objects, i),
172 ElementType, AlignmentSource::Decl);
173
174 llvm::Value *value = EmitScalarExpr(Rhs);
175 EmitStoreThroughLValue(RValue::get(value), LV, true);
176 if (TrackNeededObjects) {
177 NeededObjects.push_back(value);
178 }
179 } else {
180 // Emit the key and store it to the appropriate array slot.
181 const Expr *Key = DLE->getKeyValueElement(i).Key;
182 LValue KeyLV = MakeAddrLValue(Builder.CreateConstArrayGEP(Keys, i),
183 ElementType, AlignmentSource::Decl);
184 llvm::Value *keyValue = EmitScalarExpr(Key);
185 EmitStoreThroughLValue(RValue::get(keyValue), KeyLV, /*isInit=*/true);
186
187 // Emit the value and store it to the appropriate array slot.
188 const Expr *Value = DLE->getKeyValueElement(i).Value;
189 LValue ValueLV = MakeAddrLValue(Builder.CreateConstArrayGEP(Objects, i),
190 ElementType, AlignmentSource::Decl);
191 llvm::Value *valueValue = EmitScalarExpr(Value);
192 EmitStoreThroughLValue(RValue::get(valueValue), ValueLV, /*isInit=*/true);
193 if (TrackNeededObjects) {
194 NeededObjects.push_back(keyValue);
195 NeededObjects.push_back(valueValue);
196 }
197 }
198 }
199
200 // Generate the argument list.
201 CallArgList Args;
202 ObjCMethodDecl::param_const_iterator PI = MethodWithObjects->param_begin();
203 const ParmVarDecl *argDecl = *PI++;
204 QualType ArgQT = argDecl->getType().getUnqualifiedType();
205 Args.add(RValue::get(Objects.getPointer()), ArgQT);
206 if (DLE) {
207 argDecl = *PI++;
208 ArgQT = argDecl->getType().getUnqualifiedType();
209 Args.add(RValue::get(Keys.getPointer()), ArgQT);
210 }
211 argDecl = *PI;
212 ArgQT = argDecl->getType().getUnqualifiedType();
213 llvm::Value *Count =
214 llvm::ConstantInt::get(CGM.getTypes().ConvertType(ArgQT), NumElements);
215 Args.add(RValue::get(Count), ArgQT);
216
217 // Generate a reference to the class pointer, which will be the receiver.
218 Selector Sel = MethodWithObjects->getSelector();
219 QualType ResultType = E->getType();
220 const ObjCObjectPointerType *InterfacePointerType
221 = ResultType->getAsObjCInterfacePointerType();
222 ObjCInterfaceDecl *Class
223 = InterfacePointerType->getObjectType()->getInterface();
224 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
225 llvm::Value *Receiver = Runtime.GetClass(*this, Class);
226
227 // Generate the message send.
228 RValue result = Runtime.GenerateMessageSend(
229 *this, ReturnValueSlot(), MethodWithObjects->getReturnType(), Sel,
230 Receiver, Args, Class, MethodWithObjects);
231
232 // The above message send needs these objects, but in ARC they are
233 // passed in a buffer that is essentially __unsafe_unretained.
234 // Therefore we must prevent the optimizer from releasing them until
235 // after the call.
236 if (TrackNeededObjects) {
237 EmitARCIntrinsicUse(NeededObjects);
238 }
239
240 return Builder.CreateBitCast(result.getScalarVal(),
241 ConvertType(E->getType()));
242}
243
244llvm::Value *CodeGenFunction::EmitObjCArrayLiteral(const ObjCArrayLiteral *E) {
245 return EmitObjCCollectionLiteral(E, E->getArrayWithObjectsMethod());
246}
247
248llvm::Value *CodeGenFunction::EmitObjCDictionaryLiteral(
249 const ObjCDictionaryLiteral *E) {
250 return EmitObjCCollectionLiteral(E, E->getDictWithObjectsMethod());
251}
252
253/// Emit a selector.
254llvm::Value *CodeGenFunction::EmitObjCSelectorExpr(const ObjCSelectorExpr *E) {
255 // Untyped selector.
256 // Note that this implementation allows for non-constant strings to be passed
257 // as arguments to @selector(). Currently, the only thing preventing this
258 // behaviour is the type checking in the front end.
259 return CGM.getObjCRuntime().GetSelector(*this, E->getSelector());
260}
261
262llvm::Value *CodeGenFunction::EmitObjCProtocolExpr(const ObjCProtocolExpr *E) {
263 // FIXME: This should pass the Decl not the name.
264 return CGM.getObjCRuntime().GenerateProtocolRef(*this, E->getProtocol());
265}
266
267/// Adjust the type of an Objective-C object that doesn't match up due
268/// to type erasure at various points, e.g., related result types or the use
269/// of parameterized classes.
270static RValue AdjustObjCObjectType(CodeGenFunction &CGF, QualType ExpT,
271 RValue Result) {
272 if (!ExpT->isObjCRetainableType())
273 return Result;
274
275 // If the converted types are the same, we're done.
276 llvm::Type *ExpLLVMTy = CGF.ConvertType(ExpT);
277 if (ExpLLVMTy == Result.getScalarVal()->getType())
278 return Result;
279
280 // We have applied a substitution. Cast the rvalue appropriately.
281 return RValue::get(CGF.Builder.CreateBitCast(Result.getScalarVal(),
282 ExpLLVMTy));
283}
284
285/// Decide whether to extend the lifetime of the receiver of a
286/// returns-inner-pointer message.
287static bool
288shouldExtendReceiverForInnerPointerMessage(const ObjCMessageExpr *message) {
289 switch (message->getReceiverKind()) {
290
291 // For a normal instance message, we should extend unless the
292 // receiver is loaded from a variable with precise lifetime.
293 case ObjCMessageExpr::Instance: {
294 const Expr *receiver = message->getInstanceReceiver();
295
296 // Look through OVEs.
297 if (auto opaque = dyn_cast<OpaqueValueExpr>(receiver)) {
298 if (opaque->getSourceExpr())
299 receiver = opaque->getSourceExpr()->IgnoreParens();
300 }
301
302 const ImplicitCastExpr *ice = dyn_cast<ImplicitCastExpr>(receiver);
303 if (!ice || ice->getCastKind() != CK_LValueToRValue) return true;
304 receiver = ice->getSubExpr()->IgnoreParens();
305
306 // Look through OVEs.
307 if (auto opaque = dyn_cast<OpaqueValueExpr>(receiver)) {
308 if (opaque->getSourceExpr())
309 receiver = opaque->getSourceExpr()->IgnoreParens();
310 }
311
312 // Only __strong variables.
313 if (receiver->getType().getObjCLifetime() != Qualifiers::OCL_Strong)
314 return true;
315
316 // All ivars and fields have precise lifetime.
317 if (isa<MemberExpr>(receiver) || isa<ObjCIvarRefExpr>(receiver))
318 return false;
319
320 // Otherwise, check for variables.
321 const DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(ice->getSubExpr());
322 if (!declRef) return true;
323 const VarDecl *var = dyn_cast<VarDecl>(declRef->getDecl());
324 if (!var) return true;
325
326 // All variables have precise lifetime except local variables with
327 // automatic storage duration that aren't specially marked.
328 return (var->hasLocalStorage() &&
329 !var->hasAttr<ObjCPreciseLifetimeAttr>());
330 }
331
332 case ObjCMessageExpr::Class:
333 case ObjCMessageExpr::SuperClass:
334 // It's never necessary for class objects.
335 return false;
336
337 case ObjCMessageExpr::SuperInstance:
338 // We generally assume that 'self' lives throughout a method call.
339 return false;
340 }
341
342 llvm_unreachable("invalid receiver kind")::llvm::llvm_unreachable_internal("invalid receiver kind", "clang/lib/CodeGen/CGObjC.cpp"
, 342)
;
343}
344
345/// Given an expression of ObjC pointer type, check whether it was
346/// immediately loaded from an ARC __weak l-value.
347static const Expr *findWeakLValue(const Expr *E) {
348 assert(E->getType()->isObjCRetainableType())(static_cast <bool> (E->getType()->isObjCRetainableType
()) ? void (0) : __assert_fail ("E->getType()->isObjCRetainableType()"
, "clang/lib/CodeGen/CGObjC.cpp", 348, __extension__ __PRETTY_FUNCTION__
))
;
349 E = E->IgnoreParens();
350 if (auto CE = dyn_cast<CastExpr>(E)) {
351 if (CE->getCastKind() == CK_LValueToRValue) {
352 if (CE->getSubExpr()->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
353 return CE->getSubExpr();
354 }
355 }
356
357 return nullptr;
358}
359
360/// The ObjC runtime may provide entrypoints that are likely to be faster
361/// than an ordinary message send of the appropriate selector.
362///
363/// The entrypoints are guaranteed to be equivalent to just sending the
364/// corresponding message. If the entrypoint is implemented naively as just a
365/// message send, using it is a trade-off: it sacrifices a few cycles of
366/// overhead to save a small amount of code. However, it's possible for
367/// runtimes to detect and special-case classes that use "standard"
368/// behavior; if that's dynamically a large proportion of all objects, using
369/// the entrypoint will also be faster than using a message send.
370///
371/// If the runtime does support a required entrypoint, then this method will
372/// generate a call and return the resulting value. Otherwise it will return
373/// None and the caller can generate a msgSend instead.
374static Optional<llvm::Value *>
375tryGenerateSpecializedMessageSend(CodeGenFunction &CGF, QualType ResultType,
376 llvm::Value *Receiver,
377 const CallArgList& Args, Selector Sel,
378 const ObjCMethodDecl *method,
379 bool isClassMessage) {
380 auto &CGM = CGF.CGM;
381 if (!CGM.getCodeGenOpts().ObjCConvertMessagesToRuntimeCalls)
382 return None;
383
384 auto &Runtime = CGM.getLangOpts().ObjCRuntime;
385 switch (Sel.getMethodFamily()) {
386 case OMF_alloc:
387 if (isClassMessage &&
388 Runtime.shouldUseRuntimeFunctionsForAlloc() &&
389 ResultType->isObjCObjectPointerType()) {
390 // [Foo alloc] -> objc_alloc(Foo) or
391 // [self alloc] -> objc_alloc(self)
392 if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "alloc")
393 return CGF.EmitObjCAlloc(Receiver, CGF.ConvertType(ResultType));
394 // [Foo allocWithZone:nil] -> objc_allocWithZone(Foo) or
395 // [self allocWithZone:nil] -> objc_allocWithZone(self)
396 if (Sel.isKeywordSelector() && Sel.getNumArgs() == 1 &&
397 Args.size() == 1 && Args.front().getType()->isPointerType() &&
398 Sel.getNameForSlot(0) == "allocWithZone") {
399 const llvm::Value* arg = Args.front().getKnownRValue().getScalarVal();
400 if (isa<llvm::ConstantPointerNull>(arg))
401 return CGF.EmitObjCAllocWithZone(Receiver,
402 CGF.ConvertType(ResultType));
403 return None;
404 }
405 }
406 break;
407
408 case OMF_autorelease:
409 if (ResultType->isObjCObjectPointerType() &&
410 CGM.getLangOpts().getGC() == LangOptions::NonGC &&
411 Runtime.shouldUseARCFunctionsForRetainRelease())
412 return CGF.EmitObjCAutorelease(Receiver, CGF.ConvertType(ResultType));
413 break;
414
415 case OMF_retain:
416 if (ResultType->isObjCObjectPointerType() &&
417 CGM.getLangOpts().getGC() == LangOptions::NonGC &&
418 Runtime.shouldUseARCFunctionsForRetainRelease())
419 return CGF.EmitObjCRetainNonBlock(Receiver, CGF.ConvertType(ResultType));
420 break;
421
422 case OMF_release:
423 if (ResultType->isVoidType() &&
424 CGM.getLangOpts().getGC() == LangOptions::NonGC &&
425 Runtime.shouldUseARCFunctionsForRetainRelease()) {
426 CGF.EmitObjCRelease(Receiver, ARCPreciseLifetime);
427 return nullptr;
428 }
429 break;
430
431 default:
432 break;
433 }
434 return None;
435}
436
437CodeGen::RValue CGObjCRuntime::GeneratePossiblySpecializedMessageSend(
438 CodeGenFunction &CGF, ReturnValueSlot Return, QualType ResultType,
439 Selector Sel, llvm::Value *Receiver, const CallArgList &Args,
440 const ObjCInterfaceDecl *OID, const ObjCMethodDecl *Method,
441 bool isClassMessage) {
442 if (Optional<llvm::Value *> SpecializedResult =
443 tryGenerateSpecializedMessageSend(CGF, ResultType, Receiver, Args,
444 Sel, Method, isClassMessage)) {
445 return RValue::get(*SpecializedResult);
446 }
447 return GenerateMessageSend(CGF, Return, ResultType, Sel, Receiver, Args, OID,
448 Method);
449}
450
451static void AppendFirstImpliedRuntimeProtocols(
452 const ObjCProtocolDecl *PD,
453 llvm::UniqueVector<const ObjCProtocolDecl *> &PDs) {
454 if (!PD->isNonRuntimeProtocol()) {
455 const auto *Can = PD->getCanonicalDecl();
456 PDs.insert(Can);
457 return;
458 }
459
460 for (const auto *ParentPD : PD->protocols())
461 AppendFirstImpliedRuntimeProtocols(ParentPD, PDs);
462}
463
464std::vector<const ObjCProtocolDecl *>
465CGObjCRuntime::GetRuntimeProtocolList(ObjCProtocolDecl::protocol_iterator begin,
466 ObjCProtocolDecl::protocol_iterator end) {
467 std::vector<const ObjCProtocolDecl *> RuntimePds;
468 llvm::DenseSet<const ObjCProtocolDecl *> NonRuntimePDs;
469
470 for (; begin != end; ++begin) {
471 const auto *It = *begin;
472 const auto *Can = It->getCanonicalDecl();
473 if (Can->isNonRuntimeProtocol())
474 NonRuntimePDs.insert(Can);
475 else
476 RuntimePds.push_back(Can);
477 }
478
479 // If there are no non-runtime protocols then we can just stop now.
480 if (NonRuntimePDs.empty())
481 return RuntimePds;
482
483 // Else we have to search through the non-runtime protocol's inheritancy
484 // hierarchy DAG stopping whenever a branch either finds a runtime protocol or
485 // a non-runtime protocol without any parents. These are the "first-implied"
486 // protocols from a non-runtime protocol.
487 llvm::UniqueVector<const ObjCProtocolDecl *> FirstImpliedProtos;
488 for (const auto *PD : NonRuntimePDs)
489 AppendFirstImpliedRuntimeProtocols(PD, FirstImpliedProtos);
490
491 // Walk the Runtime list to get all protocols implied via the inclusion of
492 // this protocol, e.g. all protocols it inherits from including itself.
493 llvm::DenseSet<const ObjCProtocolDecl *> AllImpliedProtocols;
494 for (const auto *PD : RuntimePds) {
495 const auto *Can = PD->getCanonicalDecl();
496 AllImpliedProtocols.insert(Can);
497 Can->getImpliedProtocols(AllImpliedProtocols);
498 }
499
500 // Similar to above, walk the list of first-implied protocols to find the set
501 // all the protocols implied excluding the listed protocols themselves since
502 // they are not yet a part of the `RuntimePds` list.
503 for (const auto *PD : FirstImpliedProtos) {
504 PD->getImpliedProtocols(AllImpliedProtocols);
505 }
506
507 // From the first-implied list we have to finish building the final protocol
508 // list. If a protocol in the first-implied list was already implied via some
509 // inheritance path through some other protocols then it would be redundant to
510 // add it here and so we skip over it.
511 for (const auto *PD : FirstImpliedProtos) {
512 if (!AllImpliedProtocols.contains(PD)) {
513 RuntimePds.push_back(PD);
514 }
515 }
516
517 return RuntimePds;
518}
519
520/// Instead of '[[MyClass alloc] init]', try to generate
521/// 'objc_alloc_init(MyClass)'. This provides a code size improvement on the
522/// caller side, as well as the optimized objc_alloc.
523static Optional<llvm::Value *>
524tryEmitSpecializedAllocInit(CodeGenFunction &CGF, const ObjCMessageExpr *OME) {
525 auto &Runtime = CGF.getLangOpts().ObjCRuntime;
526 if (!Runtime.shouldUseRuntimeFunctionForCombinedAllocInit())
527 return None;
528
529 // Match the exact pattern '[[MyClass alloc] init]'.
530 Selector Sel = OME->getSelector();
531 if (OME->getReceiverKind() != ObjCMessageExpr::Instance ||
532 !OME->getType()->isObjCObjectPointerType() || !Sel.isUnarySelector() ||
533 Sel.getNameForSlot(0) != "init")
534 return None;
535
536 // Okay, this is '[receiver init]', check if 'receiver' is '[cls alloc]'
537 // with 'cls' a Class.
538 auto *SubOME =
539 dyn_cast<ObjCMessageExpr>(OME->getInstanceReceiver()->IgnoreParenCasts());
540 if (!SubOME)
541 return None;
542 Selector SubSel = SubOME->getSelector();
543
544 if (!SubOME->getType()->isObjCObjectPointerType() ||
545 !SubSel.isUnarySelector() || SubSel.getNameForSlot(0) != "alloc")
546 return None;
547
548 llvm::Value *Receiver = nullptr;
549 switch (SubOME->getReceiverKind()) {
550 case ObjCMessageExpr::Instance:
551 if (!SubOME->getInstanceReceiver()->getType()->isObjCClassType())
552 return None;
553 Receiver = CGF.EmitScalarExpr(SubOME->getInstanceReceiver());
554 break;
555
556 case ObjCMessageExpr::Class: {
557 QualType ReceiverType = SubOME->getClassReceiver();
558 const ObjCObjectType *ObjTy = ReceiverType->castAs<ObjCObjectType>();
559 const ObjCInterfaceDecl *ID = ObjTy->getInterface();
560 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", 560, __extension__ __PRETTY_FUNCTION__
))
;
561 Receiver = CGF.CGM.getObjCRuntime().GetClass(CGF, ID);
562 break;
563 }
564 case ObjCMessageExpr::SuperInstance:
565 case ObjCMessageExpr::SuperClass:
566 return None;
567 }
568
569 return CGF.EmitObjCAllocInit(Receiver, CGF.ConvertType(OME->getType()));
570}
571
572RValue CodeGenFunction::EmitObjCMessageExpr(const ObjCMessageExpr *E,
573 ReturnValueSlot Return) {
574 // Only the lookup mechanism and first two arguments of the method
575 // implementation vary between runtimes. We can get the receiver and
576 // arguments in generic code.
577
578 bool isDelegateInit = E->isDelegateInitCall();
579
580 const ObjCMethodDecl *method = E->getMethodDecl();
581
582 // If the method is -retain, and the receiver's being loaded from
583 // a __weak variable, peephole the entire operation to objc_loadWeakRetained.
584 if (method && E->getReceiverKind() == ObjCMessageExpr::Instance &&
585 method->getMethodFamily() == OMF_retain) {
586 if (auto lvalueExpr = findWeakLValue(E->getInstanceReceiver())) {
587 LValue lvalue = EmitLValue(lvalueExpr);
588 llvm::Value *result = EmitARCLoadWeakRetained(lvalue.getAddress(*this));
589 return AdjustObjCObjectType(*this, E->getType(), RValue::get(result));
590 }
591 }
592
593 if (Optional<llvm::Value *> Val = tryEmitSpecializedAllocInit(*this, E))
594 return AdjustObjCObjectType(*this, E->getType(), RValue::get(*Val));
595
596 // We don't retain the receiver in delegate init calls, and this is
597 // safe because the receiver value is always loaded from 'self',
598 // which we zero out. We don't want to Block_copy block receivers,
599 // though.
600 bool retainSelf =
601 (!isDelegateInit &&
602 CGM.getLangOpts().ObjCAutoRefCount &&
603 method &&
604 method->hasAttr<NSConsumesSelfAttr>());
605
606 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
607 bool isSuperMessage = false;
608 bool isClassMessage = false;
609 ObjCInterfaceDecl *OID = nullptr;
610 // Find the receiver
611 QualType ReceiverType;
612 llvm::Value *Receiver = nullptr;
613 switch (E->getReceiverKind()) {
614 case ObjCMessageExpr::Instance:
615 ReceiverType = E->getInstanceReceiver()->getType();
616 isClassMessage = ReceiverType->isObjCClassType();
617 if (retainSelf) {
618 TryEmitResult ter = tryEmitARCRetainScalarExpr(*this,
619 E->getInstanceReceiver());
620 Receiver = ter.getPointer();
621 if (ter.getInt()) retainSelf = false;
622 } else
623 Receiver = EmitScalarExpr(E->getInstanceReceiver());
624 break;
625
626 case ObjCMessageExpr::Class: {
627 ReceiverType = E->getClassReceiver();
628 OID = ReceiverType->castAs<ObjCObjectType>()->getInterface();
629 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", 629, __extension__ __PRETTY_FUNCTION__
))
;
630 Receiver = Runtime.GetClass(*this, OID);
631 isClassMessage = true;
632 break;
633 }
634
635 case ObjCMessageExpr::SuperInstance:
636 ReceiverType = E->getSuperType();
637 Receiver = LoadObjCSelf();
638 isSuperMessage = true;
639 break;
640
641 case ObjCMessageExpr::SuperClass:
642 ReceiverType = E->getSuperType();
643 Receiver = LoadObjCSelf();
644 isSuperMessage = true;
645 isClassMessage = true;
646 break;
647 }
648
649 if (retainSelf)
650 Receiver = EmitARCRetainNonBlock(Receiver);
651
652 // In ARC, we sometimes want to "extend the lifetime"
653 // (i.e. retain+autorelease) of receivers of returns-inner-pointer
654 // messages.
655 if (getLangOpts().ObjCAutoRefCount && method &&
656 method->hasAttr<ObjCReturnsInnerPointerAttr>() &&
657 shouldExtendReceiverForInnerPointerMessage(E))
658 Receiver = EmitARCRetainAutorelease(ReceiverType, Receiver);
659
660 QualType ResultType = method ? method->getReturnType() : E->getType();
661
662 CallArgList Args;
663 EmitCallArgs(Args, method, E->arguments(), /*AC*/AbstractCallee(method));
664
665 // For delegate init calls in ARC, do an unsafe store of null into
666 // self. This represents the call taking direct ownership of that
667 // value. We have to do this after emitting the other call
668 // arguments because they might also reference self, but we don't
669 // have to worry about any of them modifying self because that would
670 // be an undefined read and write of an object in unordered
671 // expressions.
672 if (isDelegateInit) {
673 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", 674, __extension__ __PRETTY_FUNCTION__
))
674 "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", 674, __extension__ __PRETTY_FUNCTION__
))
;
675
676 // Do an unsafe store of null into self.
677 Address selfAddr =
678 GetAddrOfLocalVar(cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl());
679 Builder.CreateStore(getNullForVariable(selfAddr), selfAddr);
680 }
681
682 RValue result;
683 if (isSuperMessage) {
684 // super is only valid in an Objective-C method
685 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
686 bool isCategoryImpl = isa<ObjCCategoryImplDecl>(OMD->getDeclContext());
687 result = Runtime.GenerateMessageSendSuper(*this, Return, ResultType,
688 E->getSelector(),
689 OMD->getClassInterface(),
690 isCategoryImpl,
691 Receiver,
692 isClassMessage,
693 Args,
694 method);
695 } else {
696 // Call runtime methods directly if we can.
697 result = Runtime.GeneratePossiblySpecializedMessageSend(
698 *this, Return, ResultType, E->getSelector(), Receiver, Args, OID,
699 method, isClassMessage);
700 }
701
702 // For delegate init calls in ARC, implicitly store the result of
703 // the call back into self. This takes ownership of the value.
704 if (isDelegateInit) {
705 Address selfAddr =
706 GetAddrOfLocalVar(cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl());
707 llvm::Value *newSelf = result.getScalarVal();
708
709 // The delegate return type isn't necessarily a matching type; in
710 // fact, it's quite likely to be 'id'.
711 llvm::Type *selfTy = selfAddr.getElementType();
712 newSelf = Builder.CreateBitCast(newSelf, selfTy);
713
714 Builder.CreateStore(newSelf, selfAddr);
715 }
716
717 return AdjustObjCObjectType(*this, E->getType(), result);
718}
719
720namespace {
721struct FinishARCDealloc final : EHScopeStack::Cleanup {
722 void Emit(CodeGenFunction &CGF, Flags flags) override {
723 const ObjCMethodDecl *method = cast<ObjCMethodDecl>(CGF.CurCodeDecl);
724
725 const ObjCImplDecl *impl = cast<ObjCImplDecl>(method->getDeclContext());
726 const ObjCInterfaceDecl *iface = impl->getClassInterface();
727 if (!iface->getSuperClass()) return;
728
729 bool isCategory = isa<ObjCCategoryImplDecl>(impl);
730
731 // Call [super dealloc] if we have a superclass.
732 llvm::Value *self = CGF.LoadObjCSelf();
733
734 CallArgList args;
735 CGF.CGM.getObjCRuntime().GenerateMessageSendSuper(CGF, ReturnValueSlot(),
736 CGF.getContext().VoidTy,
737 method->getSelector(),
738 iface,
739 isCategory,
740 self,
741 /*is class msg*/ false,
742 args,
743 method);
744 }
745};
746}
747
748/// StartObjCMethod - Begin emission of an ObjCMethod. This generates
749/// the LLVM function and sets the other context used by
750/// CodeGenFunction.
751void CodeGenFunction::StartObjCMethod(const ObjCMethodDecl *OMD,
752 const ObjCContainerDecl *CD) {
753 SourceLocation StartLoc = OMD->getBeginLoc();
754 FunctionArgList args;
755 // Check if we should generate debug info for this method.
756 if (OMD->hasAttr<NoDebugAttr>())
757 DebugInfo = nullptr; // disable debug info indefinitely for this function
758
759 llvm::Function *Fn = CGM.getObjCRuntime().GenerateMethod(OMD, CD);
760
761 const CGFunctionInfo &FI = CGM.getTypes().arrangeObjCMethodDeclaration(OMD);
762 if (OMD->isDirectMethod()) {
763 Fn->setVisibility(llvm::Function::HiddenVisibility);
764 CGM.SetLLVMFunctionAttributes(OMD, FI, Fn, /*IsThunk=*/false);
765 CGM.SetLLVMFunctionAttributesForDefinition(OMD, Fn);
766 } else {
767 CGM.SetInternalFunctionAttributes(OMD, Fn, FI);
768 }
769
770 args.push_back(OMD->getSelfDecl());
771 args.push_back(OMD->getCmdDecl());
772
773 args.append(OMD->param_begin(), OMD->param_end());
774
775 CurGD = OMD;
776 CurEHLocation = OMD->getEndLoc();
777
778 StartFunction(OMD, OMD->getReturnType(), Fn, FI, args,
779 OMD->getLocation(), StartLoc);
780
781 if (OMD->isDirectMethod()) {
782 // This function is a direct call, it has to implement a nil check
783 // on entry.
784 //
785 // TODO: possibly have several entry points to elide the check
786 CGM.getObjCRuntime().GenerateDirectMethodPrologue(*this, Fn, OMD, CD);
787 }
788
789 // In ARC, certain methods get an extra cleanup.
790 if (CGM.getLangOpts().ObjCAutoRefCount &&
791 OMD->isInstanceMethod() &&
792 OMD->getSelector().isUnarySelector()) {
793 const IdentifierInfo *ident =
794 OMD->getSelector().getIdentifierInfoForSlot(0);
795 if (ident->isStr("dealloc"))
796 EHStack.pushCleanup<FinishARCDealloc>(getARCCleanupKind());
797 }
798}
799
800static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF,
801 LValue lvalue, QualType type);
802
803/// Generate an Objective-C method. An Objective-C method is a C function with
804/// its pointer, name, and types registered in the class structure.
805void CodeGenFunction::GenerateObjCMethod(const ObjCMethodDecl *OMD) {
806 StartObjCMethod(OMD, OMD->getClassInterface());
807 PGO.assignRegionCounters(GlobalDecl(OMD), CurFn);
808 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", 808, __extension__ __PRETTY_FUNCTION__
))
;
809 incrementProfileCounter(OMD->getBody());
810 EmitCompoundStmtWithoutScope(*cast<CompoundStmt>(OMD->getBody()));
811 FinishFunction(OMD->getBodyRBrace());
812}
813
814/// emitStructGetterCall - Call the runtime function to load a property
815/// into the return value slot.
816static void emitStructGetterCall(CodeGenFunction &CGF, ObjCIvarDecl *ivar,
817 bool isAtomic, bool hasStrong) {
818 ASTContext &Context = CGF.getContext();
819
820 llvm::Value *src =
821 CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), CGF.LoadObjCSelf(), ivar, 0)
822 .getPointer(CGF);
823
824 // objc_copyStruct (ReturnValue, &structIvar,
825 // sizeof (Type of Ivar), isAtomic, false);
826 CallArgList args;
827
828 llvm::Value *dest =
829 CGF.Builder.CreateBitCast(CGF.ReturnValue.getPointer(), CGF.VoidPtrTy);
830 args.add(RValue::get(dest), Context.VoidPtrTy);
831
832 src = CGF.Builder.CreateBitCast(src, CGF.VoidPtrTy);
833 args.add(RValue::get(src), Context.VoidPtrTy);
834
835 CharUnits size = CGF.getContext().getTypeSizeInChars(ivar->getType());
836 args.add(RValue::get(CGF.CGM.getSize(size)), Context.getSizeType());
837 args.add(RValue::get(CGF.Builder.getInt1(isAtomic)), Context.BoolTy);
838 args.add(RValue::get(CGF.Builder.getInt1(hasStrong)), Context.BoolTy);
839
840 llvm::FunctionCallee fn = CGF.CGM.getObjCRuntime().GetGetStructFunction();
841 CGCallee callee = CGCallee::forDirect(fn);
842 CGF.EmitCall(CGF.getTypes().arrangeBuiltinFunctionCall(Context.VoidTy, args),
843 callee, ReturnValueSlot(), args);
844}
845
846/// Determine whether the given architecture supports unaligned atomic
847/// accesses. They don't have to be fast, just faster than a function
848/// call and a mutex.
849static bool hasUnalignedAtomics(llvm::Triple::ArchType arch) {
850 // FIXME: Allow unaligned atomic load/store on x86. (It is not
851 // currently supported by the backend.)
852 return false;
853}
854
855/// Return the maximum size that permits atomic accesses for the given
856/// architecture.
857static CharUnits getMaxAtomicAccessSize(CodeGenModule &CGM,
858 llvm::Triple::ArchType arch) {
859 // ARM has 8-byte atomic accesses, but it's not clear whether we
860 // want to rely on them here.
861
862 // In the default case, just assume that any size up to a pointer is
863 // fine given adequate alignment.
864 return CharUnits::fromQuantity(CGM.PointerSizeInBytes);
865}
866
867namespace {
868 class PropertyImplStrategy {
869 public:
870 enum StrategyKind {
871 /// The 'native' strategy is to use the architecture's provided
872 /// reads and writes.
873 Native,
874
875 /// Use objc_setProperty and objc_getProperty.
876 GetSetProperty,
877
878 /// Use objc_setProperty for the setter, but use expression
879 /// evaluation for the getter.
880 SetPropertyAndExpressionGet,
881
882 /// Use objc_copyStruct.
883 CopyStruct,
884
885 /// The 'expression' strategy is to emit normal assignment or
886 /// lvalue-to-rvalue expressions.
887 Expression
888 };
889
890 StrategyKind getKind() const { return StrategyKind(Kind); }
891
892 bool hasStrongMember() const { return HasStrong; }
893 bool isAtomic() const { return IsAtomic; }
894 bool isCopy() const { return IsCopy; }
895
896 CharUnits getIvarSize() const { return IvarSize; }
897 CharUnits getIvarAlignment() const { return IvarAlignment; }
898
899 PropertyImplStrategy(CodeGenModule &CGM,
900 const ObjCPropertyImplDecl *propImpl);
901
902 private:
903 unsigned Kind : 8;
904 unsigned IsAtomic : 1;
905 unsigned IsCopy : 1;
906 unsigned HasStrong : 1;
907
908 CharUnits IvarSize;
909 CharUnits IvarAlignment;
910 };
911}
912
913/// Pick an implementation strategy for the given property synthesis.
914PropertyImplStrategy::PropertyImplStrategy(CodeGenModule &CGM,
915 const ObjCPropertyImplDecl *propImpl) {
916 const ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
917 ObjCPropertyDecl::SetterKind setterKind = prop->getSetterKind();
918
919 IsCopy = (setterKind == ObjCPropertyDecl::Copy);
920 IsAtomic = prop->isAtomic();
921 HasStrong = false; // doesn't matter here.
922
923 // Evaluate the ivar's size and alignment.
924 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
925 QualType ivarType = ivar->getType();
926 auto TInfo = CGM.getContext().getTypeInfoInChars(ivarType);
927 IvarSize = TInfo.Width;
928 IvarAlignment = TInfo.Align;
929
930 // If we have a copy property, we always have to use setProperty.
931 // If the property is atomic we need to use getProperty, but in
932 // the nonatomic case we can just use expression.
933 if (IsCopy) {
934 Kind = IsAtomic ? GetSetProperty : SetPropertyAndExpressionGet;
935 return;
936 }
937
938 // Handle retain.
939 if (setterKind == ObjCPropertyDecl::Retain) {
940 // In GC-only, there's nothing special that needs to be done.
941 if (CGM.getLangOpts().getGC() == LangOptions::GCOnly) {
942 // fallthrough
943
944 // In ARC, if the property is non-atomic, use expression emission,
945 // which translates to objc_storeStrong. This isn't required, but
946 // it's slightly nicer.
947 } else if (CGM.getLangOpts().ObjCAutoRefCount && !IsAtomic) {
948 // Using standard expression emission for the setter is only
949 // acceptable if the ivar is __strong, which won't be true if
950 // the property is annotated with __attribute__((NSObject)).
951 // TODO: falling all the way back to objc_setProperty here is
952 // just laziness, though; we could still use objc_storeStrong
953 // if we hacked it right.
954 if (ivarType.getObjCLifetime() == Qualifiers::OCL_Strong)
955 Kind = Expression;
956 else
957 Kind = SetPropertyAndExpressionGet;
958 return;
959
960 // Otherwise, we need to at least use setProperty. However, if
961 // the property isn't atomic, we can use normal expression
962 // emission for the getter.
963 } else if (!IsAtomic) {
964 Kind = SetPropertyAndExpressionGet;
965 return;
966
967 // Otherwise, we have to use both setProperty and getProperty.
968 } else {
969 Kind = GetSetProperty;
970 return;
971 }
972 }
973
974 // If we're not atomic, just use expression accesses.
975 if (!IsAtomic) {
976 Kind = Expression;
977 return;
978 }
979
980 // Properties on bitfield ivars need to be emitted using expression
981 // accesses even if they're nominally atomic.
982 if (ivar->isBitField()) {
983 Kind = Expression;
984 return;
985 }
986
987 // GC-qualified or ARC-qualified ivars need to be emitted as
988 // expressions. This actually works out to being atomic anyway,
989 // except for ARC __strong, but that should trigger the above code.
990 if (ivarType.hasNonTrivialObjCLifetime() ||
991 (CGM.getLangOpts().getGC() &&
992 CGM.getContext().getObjCGCAttrKind(ivarType))) {
993 Kind = Expression;
994 return;
995 }
996
997 // Compute whether the ivar has strong members.
998 if (CGM.getLangOpts().getGC())
999 if (const RecordType *recordType = ivarType->getAs<RecordType>())
1000 HasStrong = recordType->getDecl()->hasObjectMember();
1001
1002 // We can never access structs with object members with a native
1003 // access, because we need to use write barriers. This is what
1004 // objc_copyStruct is for.
1005 if (HasStrong) {
1006 Kind = CopyStruct;
1007 return;
1008 }
1009
1010 // Otherwise, this is target-dependent and based on the size and
1011 // alignment of the ivar.
1012
1013 // If the size of the ivar is not a power of two, give up. We don't
1014 // want to get into the business of doing compare-and-swaps.
1015 if (!IvarSize.isPowerOfTwo()) {
1016 Kind = CopyStruct;
1017 return;
1018 }
1019
1020 llvm::Triple::ArchType arch =
1021 CGM.getTarget().getTriple().getArch();
1022
1023 // Most architectures require memory to fit within a single cache
1024 // line, so the alignment has to be at least the size of the access.
1025 // Otherwise we have to grab a lock.
1026 if (IvarAlignment < IvarSize && !hasUnalignedAtomics(arch)) {
1027 Kind = CopyStruct;
1028 return;
1029 }
1030
1031 // If the ivar's size exceeds the architecture's maximum atomic
1032 // access size, we have to use CopyStruct.
1033 if (IvarSize > getMaxAtomicAccessSize(CGM, arch)) {
1034 Kind = CopyStruct;
1035 return;
1036 }
1037
1038 // Otherwise, we can use native loads and stores.
1039 Kind = Native;
1040}
1041
1042/// Generate an Objective-C property getter function.
1043///
1044/// The given Decl must be an ObjCImplementationDecl. \@synthesize
1045/// is illegal within a category.
1046void CodeGenFunction::GenerateObjCGetter(ObjCImplementationDecl *IMP,
1047 const ObjCPropertyImplDecl *PID) {
1048 llvm::Constant *AtomicHelperFn =
1049 CodeGenFunction(CGM).GenerateObjCAtomicGetterCopyHelperFunction(PID);
1050 ObjCMethodDecl *OMD = PID->getGetterMethodDecl();
1051 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", 1051, __extension__ __PRETTY_FUNCTION__
))
;
1052 StartObjCMethod(OMD, IMP->getClassInterface());
1053
1054 generateObjCGetterBody(IMP, PID, OMD, AtomicHelperFn);
1055
1056 FinishFunction(OMD->getEndLoc());
1057}
1058
1059static bool hasTrivialGetExpr(const ObjCPropertyImplDecl *propImpl) {
1060 const Expr *getter = propImpl->getGetterCXXConstructor();
1061 if (!getter) return true;
1062
1063 // Sema only makes only of these when the ivar has a C++ class type,
1064 // so the form is pretty constrained.
1065
1066 // If the property has a reference type, we might just be binding a
1067 // reference, in which case the result will be a gl-value. We should
1068 // treat this as a non-trivial operation.
1069 if (getter->isGLValue())
1070 return false;
1071
1072 // If we selected a trivial copy-constructor, we're okay.
1073 if (const CXXConstructExpr *construct = dyn_cast<CXXConstructExpr>(getter))
1074 return (construct->getConstructor()->isTrivial());
1075
1076 // The constructor might require cleanups (in which case it's never
1077 // trivial).
1078 assert(isa<ExprWithCleanups>(getter))(static_cast <bool> (isa<ExprWithCleanups>(getter
)) ? void (0) : __assert_fail ("isa<ExprWithCleanups>(getter)"
, "clang/lib/CodeGen/CGObjC.cpp", 1078, __extension__ __PRETTY_FUNCTION__
))
;
1079 return false;
1080}
1081
1082/// emitCPPObjectAtomicGetterCall - Call the runtime function to
1083/// copy the ivar into the resturn slot.
1084static void emitCPPObjectAtomicGetterCall(CodeGenFunction &CGF,
1085 llvm::Value *returnAddr,
1086 ObjCIvarDecl *ivar,
1087 llvm::Constant *AtomicHelperFn) {
1088 // objc_copyCppObjectAtomic (&returnSlot, &CppObjectIvar,
1089 // AtomicHelperFn);
1090 CallArgList args;
1091
1092 // The 1st argument is the return Slot.
1093 args.add(RValue::get(returnAddr), CGF.getContext().VoidPtrTy);
1094
1095 // The 2nd argument is the address of the ivar.
1096 llvm::Value *ivarAddr =
1097 CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), CGF.LoadObjCSelf(), ivar, 0)
1098 .getPointer(CGF);
1099 ivarAddr = CGF.Builder.CreateBitCast(ivarAddr, CGF.Int8PtrTy);
1100 args.add(RValue::get(ivarAddr), CGF.getContext().VoidPtrTy);
1101
1102 // Third argument is the helper function.
1103 args.add(RValue::get(AtomicHelperFn), CGF.getContext().VoidPtrTy);
1104
1105 llvm::FunctionCallee copyCppAtomicObjectFn =
1106 CGF.CGM.getObjCRuntime().GetCppAtomicObjectGetFunction();
1107 CGCallee callee = CGCallee::forDirect(copyCppAtomicObjectFn);
1108 CGF.EmitCall(
1109 CGF.getTypes().arrangeBuiltinFunctionCall(CGF.getContext().VoidTy, args),
1110 callee, ReturnValueSlot(), args);
1111}
1112
1113void
1114CodeGenFunction::generateObjCGetterBody(const ObjCImplementationDecl *classImpl,
1115 const ObjCPropertyImplDecl *propImpl,
1116 const ObjCMethodDecl *GetterMethodDecl,
1117 llvm::Constant *AtomicHelperFn) {
1118 // If there's a non-trivial 'get' expression, we just have to emit that.
1119 if (!hasTrivialGetExpr(propImpl)) {
1120 if (!AtomicHelperFn) {
1121 auto *ret = ReturnStmt::Create(getContext(), SourceLocation(),
1122 propImpl->getGetterCXXConstructor(),
1123 /* NRVOCandidate=*/nullptr);
1124 EmitReturnStmt(*ret);
1125 }
1126 else {
1127 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
1128 emitCPPObjectAtomicGetterCall(*this, ReturnValue.getPointer(),
1129 ivar, AtomicHelperFn);
1130 }
1131 return;
1132 }
1133
1134 const ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
1135 QualType propType = prop->getType();
1136 ObjCMethodDecl *getterMethod = propImpl->getGetterMethodDecl();
1137
1138 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
1139
1140 // Pick an implementation strategy.
1141 PropertyImplStrategy strategy(CGM, propImpl);
1142 switch (strategy.getKind()) {
1143 case PropertyImplStrategy::Native: {
1144 // We don't need to do anything for a zero-size struct.
1145 if (strategy.getIvarSize().isZero())
1146 return;
1147
1148 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar, 0);
1149
1150 // Currently, all atomic accesses have to be through integer
1151 // types, so there's no point in trying to pick a prettier type.
1152 uint64_t ivarSize = getContext().toBits(strategy.getIvarSize());
1153 llvm::Type *bitcastType = llvm::Type::getIntNTy(getLLVMContext(), ivarSize);
1154
1155 // Perform an atomic load. This does not impose ordering constraints.
1156 Address ivarAddr = LV.getAddress(*this);
1157 ivarAddr = Builder.CreateElementBitCast(ivarAddr, bitcastType);
1158 llvm::LoadInst *load = Builder.CreateLoad(ivarAddr, "load");
1159 load->setAtomic(llvm::AtomicOrdering::Unordered);
1160
1161 // Store that value into the return address. Doing this with a
1162 // bitcast is likely to produce some pretty ugly IR, but it's not
1163 // the *most* terrible thing in the world.
1164 llvm::Type *retTy = ConvertType(getterMethod->getReturnType());
1165 uint64_t retTySize = CGM.getDataLayout().getTypeSizeInBits(retTy);
1166 llvm::Value *ivarVal = load;
1167 if (ivarSize > retTySize) {
1168 bitcastType = llvm::Type::getIntNTy(getLLVMContext(), retTySize);
1169 ivarVal = Builder.CreateTrunc(load, bitcastType);
1170 }
1171 Builder.CreateStore(ivarVal,
1172 Builder.CreateElementBitCast(ReturnValue, bitcastType));
1173
1174 // Make sure we don't do an autorelease.
1175 AutoreleaseResult = false;
1176 return;
1177 }
1178
1179 case PropertyImplStrategy::GetSetProperty: {
1180 llvm::FunctionCallee getPropertyFn =
1181 CGM.getObjCRuntime().GetPropertyGetFunction();
1182 if (!getPropertyFn) {
1183 CGM.ErrorUnsupported(propImpl, "Obj-C getter requiring atomic copy");
1184 return;
1185 }
1186 CGCallee callee = CGCallee::forDirect(getPropertyFn);
1187
1188 // Return (ivar-type) objc_getProperty((id) self, _cmd, offset, true).
1189 // FIXME: Can't this be simpler? This might even be worse than the
1190 // corresponding gcc code.
1191 llvm::Value *cmd =
1192 Builder.CreateLoad(GetAddrOfLocalVar(getterMethod->getCmdDecl()), "cmd");
1193 llvm::Value *self = Builder.CreateBitCast(LoadObjCSelf(), VoidPtrTy);
1194 llvm::Value *ivarOffset =
1195 EmitIvarOffset(classImpl->getClassInterface(), ivar);
1196
1197 CallArgList args;
1198 args.add(RValue::get(self), getContext().getObjCIdType());
1199 args.add(RValue::get(cmd), getContext().getObjCSelType());
1200 args.add(RValue::get(ivarOffset), getContext().getPointerDiffType());
1201 args.add(RValue::get(Builder.getInt1(strategy.isAtomic())),
1202 getContext().BoolTy);
1203
1204 // FIXME: We shouldn't need to get the function info here, the
1205 // runtime already should have computed it to build the function.
1206 llvm::CallBase *CallInstruction;
1207 RValue RV = EmitCall(getTypes().arrangeBuiltinFunctionCall(
1208 getContext().getObjCIdType(), args),
1209 callee, ReturnValueSlot(), args, &CallInstruction);
1210 if (llvm::CallInst *call = dyn_cast<llvm::CallInst>(CallInstruction))
1211 call->setTailCall();
1212
1213 // We need to fix the type here. Ivars with copy & retain are
1214 // always objects so we don't need to worry about complex or
1215 // aggregates.
1216 RV = RValue::get(Builder.CreateBitCast(
1217 RV.getScalarVal(),
1218 getTypes().ConvertType(getterMethod->getReturnType())));
1219
1220 EmitReturnOfRValue(RV, propType);
1221
1222 // objc_getProperty does an autorelease, so we should suppress ours.
1223 AutoreleaseResult = false;
1224
1225 return;
1226 }
1227
1228 case PropertyImplStrategy::CopyStruct:
1229 emitStructGetterCall(*this, ivar, strategy.isAtomic(),
1230 strategy.hasStrongMember());
1231 return;
1232
1233 case PropertyImplStrategy::Expression:
1234 case PropertyImplStrategy::SetPropertyAndExpressionGet: {
1235 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar, 0);
1236
1237 QualType ivarType = ivar->getType();
1238 switch (getEvaluationKind(ivarType)) {
1239 case TEK_Complex: {
1240 ComplexPairTy pair = EmitLoadOfComplex(LV, SourceLocation());
1241 EmitStoreOfComplex(pair, MakeAddrLValue(ReturnValue, ivarType),
1242 /*init*/ true);
1243 return;
1244 }
1245 case TEK_Aggregate: {
1246 // The return value slot is guaranteed to not be aliased, but
1247 // that's not necessarily the same as "on the stack", so
1248 // we still potentially need objc_memmove_collectable.
1249 EmitAggregateCopy(/* Dest= */ MakeAddrLValue(ReturnValue, ivarType),
1250 /* Src= */ LV, ivarType, getOverlapForReturnValue());
1251 return;
1252 }
1253 case TEK_Scalar: {
1254 llvm::Value *value;
1255 if (propType->isReferenceType()) {
1256 value = LV.getAddress(*this).getPointer();
1257 } else {
1258 // We want to load and autoreleaseReturnValue ARC __weak ivars.
1259 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
1260 if (getLangOpts().ObjCAutoRefCount) {
1261 value = emitARCRetainLoadOfScalar(*this, LV, ivarType);
1262 } else {
1263 value = EmitARCLoadWeak(LV.getAddress(*this));
1264 }
1265
1266 // Otherwise we want to do a simple load, suppressing the
1267 // final autorelease.
1268 } else {
1269 value = EmitLoadOfLValue(LV, SourceLocation()).getScalarVal();
1270 AutoreleaseResult = false;
1271 }
1272
1273 value = Builder.CreateBitCast(
1274 value, ConvertType(GetterMethodDecl->getReturnType()));
1275 }
1276
1277 EmitReturnOfRValue(RValue::get(value), propType);
1278 return;
1279 }
1280 }
1281 llvm_unreachable("bad evaluation kind")::llvm::llvm_unreachable_internal("bad evaluation kind", "clang/lib/CodeGen/CGObjC.cpp"
, 1281)
;
1282 }
1283
1284 }
1285 llvm_unreachable("bad @property implementation strategy!")::llvm::llvm_unreachable_internal("bad @property implementation strategy!"
, "clang/lib/CodeGen/CGObjC.cpp", 1285)
;
1286}
1287
1288/// emitStructSetterCall - Call the runtime function to store the value
1289/// from the first formal parameter into the given ivar.
1290static void emitStructSetterCall(CodeGenFunction &CGF, ObjCMethodDecl *OMD,
1291 ObjCIvarDecl *ivar) {
1292 // objc_copyStruct (&structIvar, &Arg,
1293 // sizeof (struct something), true, false);
1294 CallArgList args;
1295
1296 // The first argument is the address of the ivar.
1297 llvm::Value *ivarAddr =
1298 CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), CGF.LoadObjCSelf(), ivar, 0)
1299 .getPointer(CGF);
1300 ivarAddr = CGF.Builder.CreateBitCast(ivarAddr, CGF.Int8PtrTy);
1301 args.add(RValue::get(ivarAddr), CGF.getContext().VoidPtrTy);
1302
1303 // The second argument is the address of the parameter variable.
1304 ParmVarDecl *argVar = *OMD->param_begin();
1305 DeclRefExpr argRef(CGF.getContext(), argVar, false,
1306 argVar->getType().getNonReferenceType(), VK_LValue,
1307 SourceLocation());
1308 llvm::Value *argAddr = CGF.EmitLValue(&argRef).getPointer(CGF);
1309 argAddr = CGF.Builder.CreateBitCast(argAddr, CGF.Int8PtrTy);
1310 args.add(RValue::get(argAddr), CGF.getContext().VoidPtrTy);
1311
1312 // The third argument is the sizeof the type.
1313 llvm::Value *size =
1314 CGF.CGM.getSize(CGF.getContext().getTypeSizeInChars(ivar->getType()));
1315 args.add(RValue::get(size), CGF.getContext().getSizeType());
1316
1317 // The fourth argument is the 'isAtomic' flag.
1318 args.add(RValue::get(CGF.Builder.getTrue()), CGF.getContext().BoolTy);
1319
1320 // The fifth argument is the 'hasStrong' flag.
1321 // FIXME: should this really always be false?
1322 args.add(RValue::get(CGF.Builder.getFalse()), CGF.getContext().BoolTy);
1323
1324 llvm::FunctionCallee fn = CGF.CGM.getObjCRuntime().GetSetStructFunction();
1325 CGCallee callee = CGCallee::forDirect(fn);
1326 CGF.EmitCall(
1327 CGF.getTypes().arrangeBuiltinFunctionCall(CGF.getContext().VoidTy, args),
1328 callee, ReturnValueSlot(), args);
1329}
1330
1331/// emitCPPObjectAtomicSetterCall - Call the runtime function to store
1332/// the value from the first formal parameter into the given ivar, using
1333/// the Cpp API for atomic Cpp objects with non-trivial copy assignment.
1334static void emitCPPObjectAtomicSetterCall(CodeGenFunction &CGF,
1335 ObjCMethodDecl *OMD,
1336 ObjCIvarDecl *ivar,
1337 llvm::Constant *AtomicHelperFn) {
1338 // objc_copyCppObjectAtomic (&CppObjectIvar, &Arg,
1339 // AtomicHelperFn);
1340 CallArgList args;
1341
1342 // The first argument is the address of the ivar.
1343 llvm::Value *ivarAddr =
1344 CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), CGF.LoadObjCSelf(), ivar, 0)
1345 .getPointer(CGF);
1346 ivarAddr = CGF.Builder.CreateBitCast(ivarAddr, CGF.Int8PtrTy);
1347 args.add(RValue::get(ivarAddr), CGF.getContext().VoidPtrTy);
1348
1349 // The second argument is the address of the parameter variable.
1350 ParmVarDecl *argVar = *OMD->param_begin();
1351 DeclRefExpr argRef(CGF.getContext(), argVar, false,
1352 argVar->getType().getNonReferenceType(), VK_LValue,
1353 SourceLocation());
1354 llvm::Value *argAddr = CGF.EmitLValue(&argRef).getPointer(CGF);
1355 argAddr = CGF.Builder.CreateBitCast(argAddr, CGF.Int8PtrTy);
1356 args.add(RValue::get(argAddr), CGF.getContext().VoidPtrTy);
1357
1358 // Third argument is the helper function.
1359 args.add(RValue::get(AtomicHelperFn), CGF.getContext().VoidPtrTy);
1360
1361 llvm::FunctionCallee fn =
1362 CGF.CGM.getObjCRuntime().GetCppAtomicObjectSetFunction();
1363 CGCallee callee = CGCallee::forDirect(fn);
1364 CGF.EmitCall(
1365 CGF.getTypes().arrangeBuiltinFunctionCall(CGF.getContext().VoidTy, args),
1366 callee, ReturnValueSlot(), args);
1367}
1368
1369
1370static bool hasTrivialSetExpr(const ObjCPropertyImplDecl *PID) {
1371 Expr *setter = PID->getSetterCXXAssignment();
1372 if (!setter) return true;
1373
1374 // Sema only makes only of these when the ivar has a C++ class type,
1375 // so the form is pretty constrained.
1376
1377 // An operator call is trivial if the function it calls is trivial.
1378 // This also implies that there's nothing non-trivial going on with
1379 // the arguments, because operator= can only be trivial if it's a
1380 // synthesized assignment operator and therefore both parameters are
1381 // references.
1382 if (CallExpr *call = dyn_cast<CallExpr>(setter)) {
1383 if (const FunctionDecl *callee
1384 = dyn_cast_or_null<FunctionDecl>(call->getCalleeDecl()))
1385 if (callee->isTrivial())
1386 return true;
1387 return false;
1388 }
1389
1390 assert(isa<ExprWithCleanups>(setter))(static_cast <bool> (isa<ExprWithCleanups>(setter
)) ? void (0) : __assert_fail ("isa<ExprWithCleanups>(setter)"
, "clang/lib/CodeGen/CGObjC.cpp", 1390, __extension__ __PRETTY_FUNCTION__
))
;
1391 return false;
1392}
1393
1394static bool UseOptimizedSetter(CodeGenModule &CGM) {
1395 if (CGM.getLangOpts().getGC() != LangOptions::NonGC)
1396 return false;
1397 return CGM.getLangOpts().ObjCRuntime.hasOptimizedSetter();
1398}
1399
1400void
1401CodeGenFunction::generateObjCSetterBody(const ObjCImplementationDecl *classImpl,
1402 const ObjCPropertyImplDecl *propImpl,
1403 llvm::Constant *AtomicHelperFn) {
1404 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
1405 ObjCMethodDecl *setterMethod = propImpl->getSetterMethodDecl();
1406
1407 // Just use the setter expression if Sema gave us one and it's
1408 // non-trivial.
1409 if (!hasTrivialSetExpr(propImpl)) {
1410 if (!AtomicHelperFn)
1411 // If non-atomic, assignment is called directly.
1412 EmitStmt(propImpl->getSetterCXXAssignment());
1413 else
1414 // If atomic, assignment is called via a locking api.
1415 emitCPPObjectAtomicSetterCall(*this, setterMethod, ivar,
1416 AtomicHelperFn);
1417 return;
1418 }
1419
1420 PropertyImplStrategy strategy(CGM, propImpl);
1421 switch (strategy.getKind()) {
1422 case PropertyImplStrategy::Native: {
1423 // We don't need to do anything for a zero-size struct.
1424 if (strategy.getIvarSize().isZero())
1425 return;
1426
1427 Address argAddr = GetAddrOfLocalVar(*setterMethod->param_begin());
1428
1429 LValue ivarLValue =
1430 EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar, /*quals*/ 0);
1431 Address ivarAddr = ivarLValue.getAddress(*this);
1432
1433 // Currently, all atomic accesses have to be through integer
1434 // types, so there's no point in trying to pick a prettier type.
1435 llvm::Type *bitcastType =
1436 llvm::Type::getIntNTy(getLLVMContext(),
1437 getContext().toBits(strategy.getIvarSize()));
1438
1439 // Cast both arguments to the chosen operation type.
1440 argAddr = Builder.CreateElementBitCast(argAddr, bitcastType);
1441 ivarAddr = Builder.CreateElementBitCast(ivarAddr, bitcastType);
1442
1443 // This bitcast load is likely to cause some nasty IR.
1444 llvm::Value *load = Builder.CreateLoad(argAddr);
1445
1446 // Perform an atomic store. There are no memory ordering requirements.
1447 llvm::StoreInst *store = Builder.CreateStore(load, ivarAddr);
1448 store->setAtomic(llvm::AtomicOrdering::Unordered);
1449 return;
1450 }
1451
1452 case PropertyImplStrategy::GetSetProperty:
1453 case PropertyImplStrategy::SetPropertyAndExpressionGet: {
1454
1455 llvm::FunctionCallee setOptimizedPropertyFn = nullptr;
1456 llvm::FunctionCallee setPropertyFn = nullptr;
1457 if (UseOptimizedSetter(CGM)) {
1458 // 10.8 and iOS 6.0 code and GC is off
1459 setOptimizedPropertyFn =
1460 CGM.getObjCRuntime().GetOptimizedPropertySetFunction(
1461 strategy.isAtomic(), strategy.isCopy());
1462 if (!setOptimizedPropertyFn) {
1463 CGM.ErrorUnsupported(propImpl, "Obj-C optimized setter - NYI");
1464 return;
1465 }
1466 }
1467 else {
1468 setPropertyFn = CGM.getObjCRuntime().GetPropertySetFunction();
1469 if (!setPropertyFn) {
1470 CGM.ErrorUnsupported(propImpl, "Obj-C setter requiring atomic copy");
1471 return;
1472 }
1473 }
1474
1475 // Emit objc_setProperty((id) self, _cmd, offset, arg,
1476 // <is-atomic>, <is-copy>).
1477 llvm::Value *cmd =
1478 Builder.CreateLoad(GetAddrOfLocalVar(setterMethod->getCmdDecl()));
1479 llvm::Value *self =
1480 Builder.CreateBitCast(LoadObjCSelf(), VoidPtrTy);
1481 llvm::Value *ivarOffset =
1482 EmitIvarOffset(classImpl->getClassInterface(), ivar);
1483 Address argAddr = GetAddrOfLocalVar(*setterMethod->param_begin());
1484 llvm::Value *arg = Builder.CreateLoad(argAddr, "arg");
1485 arg = Builder.CreateBitCast(arg, VoidPtrTy);
1486
1487 CallArgList args;
1488 args.add(RValue::get(self), getContext().getObjCIdType());
1489 args.add(RValue::get(cmd), getContext().getObjCSelType());
1490 if (setOptimizedPropertyFn) {
1491 args.add(RValue::get(arg), getContext().getObjCIdType());
1492 args.add(RValue::get(ivarOffset), getContext().getPointerDiffType());
1493 CGCallee callee = CGCallee::forDirect(setOptimizedPropertyFn);
1494 EmitCall(getTypes().arrangeBuiltinFunctionCall(getContext().VoidTy, args),
1495 callee, ReturnValueSlot(), args);
1496 } else {
1497 args.add(RValue::get(ivarOffset), getContext().getPointerDiffType());
1498 args.add(RValue::get(arg), getContext().getObjCIdType());
1499 args.add(RValue::get(Builder.getInt1(strategy.isAtomic())),
1500 getContext().BoolTy);
1501 args.add(RValue::get(Builder.getInt1(strategy.isCopy())),
1502 getContext().BoolTy);
1503 // FIXME: We shouldn't need to get the function info here, the runtime
1504 // already should have computed it to build the function.
1505 CGCallee callee = CGCallee::forDirect(setPropertyFn);
1506 EmitCall(getTypes().arrangeBuiltinFunctionCall(getContext().VoidTy, args),
1507 callee, ReturnValueSlot(), args);
1508 }
1509
1510 return;
1511 }
1512
1513 case PropertyImplStrategy::CopyStruct:
1514 emitStructSetterCall(*this, setterMethod, ivar);
1515 return;
1516
1517 case PropertyImplStrategy::Expression:
1518 break;
1519 }
1520
1521 // Otherwise, fake up some ASTs and emit a normal assignment.
1522 ValueDecl *selfDecl = setterMethod->getSelfDecl();
1523 DeclRefExpr self(getContext(), selfDecl, false, selfDecl->getType(),
1524 VK_LValue, SourceLocation());
1525 ImplicitCastExpr selfLoad(ImplicitCastExpr::OnStack, selfDecl->getType(),
1526 CK_LValueToRValue, &self, VK_PRValue,
1527 FPOptionsOverride());
1528 ObjCIvarRefExpr ivarRef(ivar, ivar->getType().getNonReferenceType(),
1529 SourceLocation(), SourceLocation(),
1530 &selfLoad, true, true);
1531
1532 ParmVarDecl *argDecl = *setterMethod->param_begin();
1533 QualType argType = argDecl->getType().getNonReferenceType();
1534 DeclRefExpr arg(getContext(), argDecl, false, argType, VK_LValue,
1535 SourceLocation());
1536 ImplicitCastExpr argLoad(ImplicitCastExpr::OnStack,
1537 argType.getUnqualifiedType(), CK_LValueToRValue,
1538 &arg, VK_PRValue, FPOptionsOverride());
1539
1540 // The property type can differ from the ivar type in some situations with
1541 // Objective-C pointer types, we can always bit cast the RHS in these cases.
1542 // The following absurdity is just to ensure well-formed IR.
1543 CastKind argCK = CK_NoOp;
1544 if (ivarRef.getType()->isObjCObjectPointerType()) {
1545 if (argLoad.getType()->isObjCObjectPointerType())
1546 argCK = CK_BitCast;
1547 else if (argLoad.getType()->isBlockPointerType())
1548 argCK = CK_BlockPointerToObjCPointerCast;
1549 else
1550 argCK = CK_CPointerToObjCPointerCast;
1551 } else if (ivarRef.getType()->isBlockPointerType()) {
1552 if (argLoad.getType()->isBlockPointerType())
1553 argCK = CK_BitCast;
1554 else
1555 argCK = CK_AnyPointerToBlockPointerCast;
1556 } else if (ivarRef.getType()->isPointerType()) {
1557 argCK = CK_BitCast;
1558 } else if (argLoad.getType()->isAtomicType() &&
1559 !ivarRef.getType()->isAtomicType()) {
1560 argCK = CK_AtomicToNonAtomic;
1561 } else if (!argLoad.getType()->isAtomicType() &&
1562 ivarRef.getType()->isAtomicType()) {
1563 argCK = CK_NonAtomicToAtomic;
1564 }
1565 ImplicitCastExpr argCast(ImplicitCastExpr::OnStack, ivarRef.getType(), argCK,
1566 &argLoad, VK_PRValue, FPOptionsOverride());
1567 Expr *finalArg = &argLoad;
1568 if (!getContext().hasSameUnqualifiedType(ivarRef.getType(),
1569 argLoad.getType()))
1570 finalArg = &argCast;
1571
1572 BinaryOperator *assign = BinaryOperator::Create(
1573 getContext(), &ivarRef, finalArg, BO_Assign, ivarRef.getType(),
1574 VK_PRValue, OK_Ordinary, SourceLocation(), FPOptionsOverride());
1575 EmitStmt(assign);
1576}
1577
1578/// Generate an Objective-C property setter function.
1579///
1580/// The given Decl must be an ObjCImplementationDecl. \@synthesize
1581/// is illegal within a category.
1582void CodeGenFunction::GenerateObjCSetter(ObjCImplementationDecl *IMP,
1583 const ObjCPropertyImplDecl *PID) {
1584 llvm::Constant *AtomicHelperFn =
1585 CodeGenFunction(CGM).GenerateObjCAtomicSetterCopyHelperFunction(PID);
1586 ObjCMethodDecl *OMD = PID->getSetterMethodDecl();
1587 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", 1587, __extension__ __PRETTY_FUNCTION__
))
;
1588 StartObjCMethod(OMD, IMP->getClassInterface());
1589
1590 generateObjCSetterBody(IMP, PID, AtomicHelperFn);
1591
1592 FinishFunction(OMD->getEndLoc());
1593}
1594
1595namespace {
1596 struct DestroyIvar final : EHScopeStack::Cleanup {
1597 private:
1598 llvm::Value *addr;
1599 const ObjCIvarDecl *ivar;
1600 CodeGenFunction::Destroyer *destroyer;
1601 bool useEHCleanupForArray;
1602 public:
1603 DestroyIvar(llvm::Value *addr, const ObjCIvarDecl *ivar,
1604 CodeGenFunction::Destroyer *destroyer,
1605 bool useEHCleanupForArray)
1606 : addr(addr), ivar(ivar), destroyer(destroyer),
1607 useEHCleanupForArray(useEHCleanupForArray) {}
1608
1609 void Emit(CodeGenFunction &CGF, Flags flags) override {
1610 LValue lvalue
1611 = CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), addr, ivar, /*CVR*/ 0);
1612 CGF.emitDestroy(lvalue.getAddress(CGF), ivar->getType(), destroyer,
1613 flags.isForNormalCleanup() && useEHCleanupForArray);
1614 }
1615 };
1616}
1617
1618/// Like CodeGenFunction::destroyARCStrong, but do it with a call.
1619static void destroyARCStrongWithStore(CodeGenFunction &CGF,
1620 Address addr,
1621 QualType type) {
1622 llvm::Value *null = getNullForVariable(addr);
1623 CGF.EmitARCStoreStrongCall(addr, null, /*ignored*/ true);
1624}
1625
1626static void emitCXXDestructMethod(CodeGenFunction &CGF,
1627 ObjCImplementationDecl *impl) {
1628 CodeGenFunction::RunCleanupsScope scope(CGF);
1629
1630 llvm::Value *self = CGF.LoadObjCSelf();
1631
1632 const ObjCInterfaceDecl *iface = impl->getClassInterface();
1633 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
1634 ivar; ivar = ivar->getNextIvar()) {
1635 QualType type = ivar->getType();
1636
1637 // Check whether the ivar is a destructible type.
1638 QualType::DestructionKind dtorKind = type.isDestructedType();
1639 if (!dtorKind) continue;
1640
1641 CodeGenFunction::Destroyer *destroyer = nullptr;
1642
1643 // Use a call to objc_storeStrong to destroy strong ivars, for the
1644 // general benefit of the tools.
1645 if (dtorKind == QualType::DK_objc_strong_lifetime) {
1646 destroyer = destroyARCStrongWithStore;
1647
1648 // Otherwise use the default for the destruction kind.
1649 } else {
1650 destroyer = CGF.getDestroyer(dtorKind);
1651 }
1652
1653 CleanupKind cleanupKind = CGF.getCleanupKind(dtorKind);
1654
1655 CGF.EHStack.pushCleanup<DestroyIvar>(cleanupKind, self, ivar, destroyer,
1656 cleanupKind & EHCleanup);
1657 }
1658
1659 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", 1659, __extension__ __PRETTY_FUNCTION__
))
;
1660}
1661
1662void CodeGenFunction::GenerateObjCCtorDtorMethod(ObjCImplementationDecl *IMP,
1663 ObjCMethodDecl *MD,
1664 bool ctor) {
1665 MD->createImplicitParams(CGM.getContext(), IMP->getClassInterface());
1666 StartObjCMethod(MD, IMP->getClassInterface());
1667
1668 // Emit .cxx_construct.
1669 if (ctor) {
1670 // Suppress the final autorelease in ARC.
1671 AutoreleaseResult = false;
1672
1673 for (const auto *IvarInit : IMP->inits()) {
1674 FieldDecl *Field = IvarInit->getAnyMember();
1675 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(Field);
1676 LValue LV = EmitLValueForIvar(TypeOfSelfObject(),
1677 LoadObjCSelf(), Ivar, 0);
1678 EmitAggExpr(IvarInit->getInit(),
1679 AggValueSlot::forLValue(LV, *this, AggValueSlot::IsDestructed,
1680 AggValueSlot::DoesNotNeedGCBarriers,
1681 AggValueSlot::IsNotAliased,
1682 AggValueSlot::DoesNotOverlap));
1683 }
1684 // constructor returns 'self'.
1685 CodeGenTypes &Types = CGM.getTypes();
1686 QualType IdTy(CGM.getContext().getObjCIdType());
1687 llvm::Value *SelfAsId =
1688 Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy));
1689 EmitReturnOfRValue(RValue::get(SelfAsId), IdTy);
1690
1691 // Emit .cxx_destruct.
1692 } else {
1693 emitCXXDestructMethod(*this, IMP);
1694 }
1695 FinishFunction();
1696}
1697
1698llvm::Value *CodeGenFunction::LoadObjCSelf() {
1699 VarDecl *Self = cast<ObjCMethodDecl>(CurFuncDecl)->getSelfDecl();
1700 DeclRefExpr DRE(getContext(), Self,
1701 /*is enclosing local*/ (CurFuncDecl != CurCodeDecl),
1702 Self->getType(), VK_LValue, SourceLocation());
1703 return EmitLoadOfScalar(EmitDeclRefLValue(&DRE), SourceLocation());
1704}
1705
1706QualType CodeGenFunction::TypeOfSelfObject() {
1707 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
1708 ImplicitParamDecl *selfDecl = OMD->getSelfDecl();
1709 const ObjCObjectPointerType *PTy = cast<ObjCObjectPointerType>(
1710 getContext().getCanonicalType(selfDecl->getType()));
1711 return PTy->getPointeeType();
1712}
1713
1714void CodeGenFunction::EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S){
1715 llvm::FunctionCallee EnumerationMutationFnPtr =
1716 CGM.getObjCRuntime().EnumerationMutationFunction();
1717 if (!EnumerationMutationFnPtr) {
1718 CGM.ErrorUnsupported(&S, "Obj-C fast enumeration for this runtime");
1719 return;
1720 }
1721 CGCallee EnumerationMutationFn =
1722 CGCallee::forDirect(EnumerationMutationFnPtr);
1723
1724 CGDebugInfo *DI = getDebugInfo();
1725 if (DI)
1726 DI->EmitLexicalBlockStart(Builder, S.getSourceRange().getBegin());
1727
1728 RunCleanupsScope ForScope(*this);
1729
1730 // The local variable comes into scope immediately.
1731 AutoVarEmission variable = AutoVarEmission::invalid();
1732 if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement()))
1733 variable = EmitAutoVarAlloca(*cast<VarDecl>(SD->getSingleDecl()));
1734
1735 JumpDest LoopEnd = getJumpDestInCurrentScope("forcoll.end");
1736
1737 // Fast enumeration state.
1738 QualType StateTy = CGM.getObjCFastEnumerationStateType();
1739 Address StatePtr = CreateMemTemp(StateTy, "state.ptr");
1740 EmitNullInitialization(StatePtr, StateTy);
1741
1742 // Number of elements in the items array.
1743 static const unsigned NumItems = 16;
1744
1745 // Fetch the countByEnumeratingWithState:objects:count: selector.
1746 IdentifierInfo *II[] = {
1747 &CGM.getContext().Idents.get("countByEnumeratingWithState"),
1748 &CGM.getContext().Idents.get("objects"),
1749 &CGM.getContext().Idents.get("count")
1750 };
1751 Selector FastEnumSel =
1752 CGM.getContext().Selectors.getSelector(llvm::array_lengthof(II), &II[0]);
1753
1754 QualType ItemsTy =
1755 getContext().getConstantArrayType(getContext().getObjCIdType(),
1756 llvm::APInt(32, NumItems), nullptr,
1757 ArrayType::Normal, 0);
1758 Address ItemsPtr = CreateMemTemp(ItemsTy, "items.ptr");
1759
1760 // Emit the collection pointer. In ARC, we do a retain.
1761 llvm::Value *Collection;
1762 if (getLangOpts().ObjCAutoRefCount) {
1763 Collection = EmitARCRetainScalarExpr(S.getCollection());
1764
1765 // Enter a cleanup to do the release.
1766 EmitObjCConsumeObject(S.getCollection()->getType(), Collection);
1767 } else {
1768 Collection = EmitScalarExpr(S.getCollection());
1769 }
1770
1771 // The 'continue' label needs to appear within the cleanup for the
1772 // collection object.
1773 JumpDest AfterBody = getJumpDestInCurrentScope("forcoll.next");
1774
1775 // Send it our message:
1776 CallArgList Args;
1777
1778 // The first argument is a temporary of the enumeration-state type.
1779 Args.add(RValue::get(StatePtr.getPointer()),
1780 getContext().getPointerType(StateTy));
1781
1782 // The second argument is a temporary array with space for NumItems
1783 // pointers. We'll actually be loading elements from the array
1784 // pointer written into the control state; this buffer is so that
1785 // collections that *aren't* backed by arrays can still queue up
1786 // batches of elements.
1787 Args.add(RValue::get(ItemsPtr.getPointer()),
1788 getContext().getPointerType(ItemsTy));
1789
1790 // The third argument is the capacity of that temporary array.
1791 llvm::Type *NSUIntegerTy = ConvertType(getContext().getNSUIntegerType());
1792 llvm::Constant *Count = llvm::ConstantInt::get(NSUIntegerTy, NumItems);
1793 Args.add(RValue::get(Count), getContext().getNSUIntegerType());
1794
1795 // Start the enumeration.
1796 RValue CountRV =
1797 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
1798 getContext().getNSUIntegerType(),
1799 FastEnumSel, Collection, Args);
1800
1801 // The initial number of objects that were returned in the buffer.
1802 llvm::Value *initialBufferLimit = CountRV.getScalarVal();
1803
1804 llvm::BasicBlock *EmptyBB = createBasicBlock("forcoll.empty");
1805 llvm::BasicBlock *LoopInitBB = createBasicBlock("forcoll.loopinit");
1806
1807 llvm::Value *zero = llvm::Constant::getNullValue(NSUIntegerTy);
1808
1809 // If the limit pointer was zero to begin with, the collection is
1810 // empty; skip all this. Set the branch weight assuming this has the same
1811 // probability of exiting the loop as any other loop exit.
1812 uint64_t EntryCount = getCurrentProfileCount();
1813 Builder.CreateCondBr(
1814 Builder.CreateICmpEQ(initialBufferLimit, zero, "iszero"), EmptyBB,
1815 LoopInitBB,
1816 createProfileWeights(EntryCount, getProfileCount(S.getBody())));
1817
1818 // Otherwise, initialize the loop.
1819 EmitBlock(LoopInitBB);
1820
1821 // Save the initial mutations value. This is the value at an
1822 // address that was written into the state object by
1823 // countByEnumeratingWithState:objects:count:.
1824 Address StateMutationsPtrPtr =
1825 Builder.CreateStructGEP(StatePtr, 2, "mutationsptr.ptr");
1826 llvm::Value *StateMutationsPtr
1827 = Builder.CreateLoad(StateMutationsPtrPtr, "mutationsptr");
1828
1829 llvm::Type *UnsignedLongTy = ConvertType(getContext().UnsignedLongTy);
1830 llvm::Value *initialMutations =
1831 Builder.CreateAlignedLoad(UnsignedLongTy, StateMutationsPtr,
1832 getPointerAlign(), "forcoll.initial-mutations");
1833
1834 // Start looping. This is the point we return to whenever we have a
1835 // fresh, non-empty batch of objects.
1836 llvm::BasicBlock *LoopBodyBB = createBasicBlock("forcoll.loopbody");
1837 EmitBlock(LoopBodyBB);
1838
1839 // The current index into the buffer.
1840 llvm::PHINode *index = Builder.CreatePHI(NSUIntegerTy, 3, "forcoll.index");
1841 index->addIncoming(zero, LoopInitBB);
1842
1843 // The current buffer size.
1844 llvm::PHINode *count = Builder.CreatePHI(NSUIntegerTy, 3, "forcoll.count");
1845 count->addIncoming(initialBufferLimit, LoopInitBB);
1846
1847 incrementProfileCounter(&S);
1848
1849 // Check whether the mutations value has changed from where it was
1850 // at start. StateMutationsPtr should actually be invariant between
1851 // refreshes.
1852 StateMutationsPtr = Builder.CreateLoad(StateMutationsPtrPtr, "mutationsptr");
1853 llvm::Value *currentMutations
1854 = Builder.CreateAlignedLoad(UnsignedLongTy, StateMutationsPtr,
1855 getPointerAlign(), "statemutations");
1856
1857 llvm::BasicBlock *WasMutatedBB = createBasicBlock("forcoll.mutated");
1858 llvm::BasicBlock *WasNotMutatedBB = createBasicBlock("forcoll.notmutated");
1859
1860 Builder.CreateCondBr(Builder.CreateICmpEQ(currentMutations, initialMutations),
1861 WasNotMutatedBB, WasMutatedBB);
1862
1863 // If so, call the enumeration-mutation function.
1864 EmitBlock(WasMutatedBB);
1865 llvm::Type *ObjCIdType = ConvertType(getContext().getObjCIdType());
1866 llvm::Value *V =
1867 Builder.CreateBitCast(Collection, ObjCIdType);
1868 CallArgList Args2;
1869 Args2.add(RValue::get(V), getContext().getObjCIdType());
1870 // FIXME: We shouldn't need to get the function info here, the runtime already
1871 // should have computed it to build the function.
1872 EmitCall(
1873 CGM.getTypes().arrangeBuiltinFunctionCall(getContext().VoidTy, Args2),
1874 EnumerationMutationFn, ReturnValueSlot(), Args2);
1875
1876 // Otherwise, or if the mutation function returns, just continue.
1877 EmitBlock(WasNotMutatedBB);
1878
1879 // Initialize the element variable.
1880 RunCleanupsScope elementVariableScope(*this);
1881 bool elementIsVariable;
1882 LValue elementLValue;
1883 QualType elementType;
1884 if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement())) {
1885 // Initialize the variable, in case it's a __block variable or something.
1886 EmitAutoVarInit(variable);
1887
1888 const VarDecl *D = cast<VarDecl>(SD->getSingleDecl());
1889 DeclRefExpr tempDRE(getContext(), const_cast<VarDecl *>(D), false,
1890 D->getType(), VK_LValue, SourceLocation());
1891 elementLValue = EmitLValue(&tempDRE);
1892 elementType = D->getType();
1893 elementIsVariable = true;
1894
1895 if (D->isARCPseudoStrong())
1896 elementLValue.getQuals().setObjCLifetime(Qualifiers::OCL_ExplicitNone);
1897 } else {
1898 elementLValue = LValue(); // suppress warning
1899 elementType = cast<Expr>(S.getElement())->getType();
1900 elementIsVariable = false;
1901 }
1902 llvm::Type *convertedElementType = ConvertType(elementType);
1903
1904 // Fetch the buffer out of the enumeration state.
1905 // TODO: this pointer should actually be invariant between
1906 // refreshes, which would help us do certain loop optimizations.
1907 Address StateItemsPtr =
1908 Builder.CreateStructGEP(StatePtr, 1, "stateitems.ptr");
1909 llvm::Value *EnumStateItems =
1910 Builder.CreateLoad(StateItemsPtr, "stateitems");
1911
1912 // Fetch the value at the current index from the buffer.
1913 llvm::Value *CurrentItemPtr = Builder.CreateGEP(
1914 ObjCIdType, EnumStateItems, index, "currentitem.ptr");
1915 llvm::Value *CurrentItem =
1916 Builder.CreateAlignedLoad(ObjCIdType, CurrentItemPtr, getPointerAlign());
1917
1918 if (SanOpts.has(SanitizerKind::ObjCCast)) {
1919 // Before using an item from the collection, check that the implicit cast
1920 // from id to the element type is valid. This is done with instrumentation
1921 // roughly corresponding to:
1922 //
1923 // if (![item isKindOfClass:expectedCls]) { /* emit diagnostic */ }
1924 const ObjCObjectPointerType *ObjPtrTy =
1925 elementType->getAsObjCInterfacePointerType();
1926 const ObjCInterfaceType *InterfaceTy =
1927 ObjPtrTy ? ObjPtrTy->getInterfaceType() : nullptr;
1928 if (InterfaceTy) {
1929 SanitizerScope SanScope(this);
1930 auto &C = CGM.getContext();
1931 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", 1931, __extension__ __PRETTY_FUNCTION__
))
;
1932 Selector IsKindOfClassSel = GetUnarySelector("isKindOfClass", C);
1933 CallArgList IsKindOfClassArgs;
1934 llvm::Value *Cls =
1935 CGM.getObjCRuntime().GetClass(*this, InterfaceTy->getDecl());
1936 IsKindOfClassArgs.add(RValue::get(Cls), C.getObjCClassType());
1937 llvm::Value *IsClass =
1938 CGM.getObjCRuntime()
1939 .GenerateMessageSend(*this, ReturnValueSlot(), C.BoolTy,
1940 IsKindOfClassSel, CurrentItem,
1941 IsKindOfClassArgs)
1942 .getScalarVal();
1943 llvm::Constant *StaticData[] = {
1944 EmitCheckSourceLocation(S.getBeginLoc()),
1945 EmitCheckTypeDescriptor(QualType(InterfaceTy, 0))};
1946 EmitCheck({{IsClass, SanitizerKind::ObjCCast}},
1947 SanitizerHandler::InvalidObjCCast,
1948 ArrayRef<llvm::Constant *>(StaticData), CurrentItem);
1949 }
1950 }
1951
1952 // Cast that value to the right type.
1953 CurrentItem = Builder.CreateBitCast(CurrentItem, convertedElementType,
1954 "currentitem");
1955
1956 // Make sure we have an l-value. Yes, this gets evaluated every
1957 // time through the loop.
1958 if (!elementIsVariable) {
1959 elementLValue = EmitLValue(cast<Expr>(S.getElement()));
1960 EmitStoreThroughLValue(RValue::get(CurrentItem), elementLValue);
1961 } else {
1962 EmitStoreThroughLValue(RValue::get(CurrentItem), elementLValue,
1963 /*isInit*/ true);
1964 }
1965
1966 // If we do have an element variable, this assignment is the end of
1967 // its initialization.
1968 if (elementIsVariable)
1969 EmitAutoVarCleanups(variable);
1970
1971 // Perform the loop body, setting up break and continue labels.
1972 BreakContinueStack.push_back(BreakContinue(LoopEnd, AfterBody));
1973 {
1974 RunCleanupsScope Scope(*this);
1975 EmitStmt(S.getBody());
1976 }
1977 BreakContinueStack.pop_back();
1978
1979 // Destroy the element variable now.
1980 elementVariableScope.ForceCleanup();
1981
1982 // Check whether there are more elements.
1983 EmitBlock(AfterBody.getBlock());
1984
1985 llvm::BasicBlock *FetchMoreBB = createBasicBlock("forcoll.refetch");
1986
1987 // First we check in the local buffer.
1988 llvm::Value *indexPlusOne =
1989 Builder.CreateAdd(index, llvm::ConstantInt::get(NSUIntegerTy, 1));
1990
1991 // If we haven't overrun the buffer yet, we can continue.
1992 // Set the branch weights based on the simplifying assumption that this is
1993 // like a while-loop, i.e., ignoring that the false branch fetches more
1994 // elements and then returns to the loop.
1995 Builder.CreateCondBr(
1996 Builder.CreateICmpULT(indexPlusOne, count), LoopBodyBB, FetchMoreBB,
1997 createProfileWeights(getProfileCount(S.getBody()), EntryCount));
1998
1999 index->addIncoming(indexPlusOne, AfterBody.getBlock());
2000 count->addIncoming(count, AfterBody.getBlock());
2001
2002 // Otherwise, we have to fetch more elements.
2003 EmitBlock(FetchMoreBB);
2004
2005 CountRV =
2006 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
2007 getContext().getNSUIntegerType(),
2008 FastEnumSel, Collection, Args);
2009
2010 // If we got a zero count, we're done.
2011 llvm::Value *refetchCount = CountRV.getScalarVal();
2012
2013 // (note that the message send might split FetchMoreBB)
2014 index->addIncoming(zero, Builder.GetInsertBlock());
2015 count->addIncoming(refetchCount, Builder.GetInsertBlock());
2016
2017 Builder.CreateCondBr(Builder.CreateICmpEQ(refetchCount, zero),
2018 EmptyBB, LoopBodyBB);
2019
2020 // No more elements.
2021 EmitBlock(EmptyBB);
2022
2023 if (!elementIsVariable) {
2024 // If the element was not a declaration, set it to be null.
2025
2026 llvm::Value *null = llvm::Constant::getNullValue(convertedElementType);
2027 elementLValue = EmitLValue(cast<Expr>(S.getElement()));
2028 EmitStoreThroughLValue(RValue::get(null), elementLValue);
2029 }
2030
2031 if (DI)
2032 DI->EmitLexicalBlockEnd(Builder, S.getSourceRange().getEnd());
2033
2034 ForScope.ForceCleanup();
2035 EmitBlock(LoopEnd.getBlock());
2036}
2037
2038void CodeGenFunction::EmitObjCAtTryStmt(const ObjCAtTryStmt &S) {
2039 CGM.getObjCRuntime().EmitTryStmt(*this, S);
2040}
2041
2042void CodeGenFunction::EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S) {
2043 CGM.getObjCRuntime().EmitThrowStmt(*this, S);
2044}
2045
2046void CodeGenFunction::EmitObjCAtSynchronizedStmt(
2047 const ObjCAtSynchronizedStmt &S) {
2048 CGM.getObjCRuntime().EmitSynchronizedStmt(*this, S);
2049}
2050
2051namespace {
2052 struct CallObjCRelease final : EHScopeStack::Cleanup {
2053 CallObjCRelease(llvm::Value *object) : object(object) {}
2054 llvm::Value *object;
2055
2056 void Emit(CodeGenFunction &CGF, Flags flags) override {
2057 // Releases at the end of the full-expression are imprecise.
2058 CGF.EmitARCRelease(object, ARCImpreciseLifetime);
2059 }
2060 };
2061}
2062
2063/// Produce the code for a CK_ARCConsumeObject. Does a primitive
2064/// release at the end of the full-expression.
2065llvm::Value *CodeGenFunction::EmitObjCConsumeObject(QualType type,
2066 llvm::Value *object) {
2067 // If we're in a conditional branch, we need to make the cleanup
2068 // conditional.
2069 pushFullExprCleanup<CallObjCRelease>(getARCCleanupKind(), object);
2070 return object;
2071}
2072
2073llvm::Value *CodeGenFunction::EmitObjCExtendObjectLifetime(QualType type,
2074 llvm::Value *value) {
2075 return EmitARCRetainAutorelease(type, value);
2076}
2077
2078/// Given a number of pointers, inform the optimizer that they're
2079/// being intrinsically used up until this point in the program.
2080void CodeGenFunction::EmitARCIntrinsicUse(ArrayRef<llvm::Value*> values) {
2081 llvm::Function *&fn = CGM.getObjCEntrypoints().clang_arc_use;
2082 if (!fn)
2083 fn = CGM.getIntrinsic(llvm::Intrinsic::objc_clang_arc_use);
2084
2085 // This isn't really a "runtime" function, but as an intrinsic it
2086 // doesn't really matter as long as we align things up.
2087 EmitNounwindRuntimeCall(fn, values);
2088}
2089
2090/// Emit a call to "clang.arc.noop.use", which consumes the result of a call
2091/// that has operand bundle "clang.arc.attachedcall".
2092void CodeGenFunction::EmitARCNoopIntrinsicUse(ArrayRef<llvm::Value *> values) {
2093 llvm::Function *&fn = CGM.getObjCEntrypoints().clang_arc_noop_use;
2094 if (!fn)
2095 fn = CGM.getIntrinsic(llvm::Intrinsic::objc_clang_arc_noop_use);
2096 EmitNounwindRuntimeCall(fn, values);
2097}
2098
2099static void setARCRuntimeFunctionLinkage(CodeGenModule &CGM, llvm::Value *RTF) {
2100 if (auto *F = dyn_cast<llvm::Function>(RTF)) {
2101 // If the target runtime doesn't naturally support ARC, emit weak
2102 // references to the runtime support library. We don't really
2103 // permit this to fail, but we need a particular relocation style.
2104 if (!CGM.getLangOpts().ObjCRuntime.hasNativeARC() &&
2105 !CGM.getTriple().isOSBinFormatCOFF()) {
2106 F->setLinkage(llvm::Function::ExternalWeakLinkage);
2107 }
2108 }
2109}
2110
2111static void setARCRuntimeFunctionLinkage(CodeGenModule &CGM,
2112 llvm::FunctionCallee RTF) {
2113 setARCRuntimeFunctionLinkage(CGM, RTF.getCallee());
2114}
2115
2116static llvm::Function *getARCIntrinsic(llvm::Intrinsic::ID IntID,
2117 CodeGenModule &CGM) {
2118 llvm::Function *fn = CGM.getIntrinsic(IntID);
2119 setARCRuntimeFunctionLinkage(CGM, fn);
2120 return fn;
2121}
2122
2123/// Perform an operation having the signature
2124/// i8* (i8*)
2125/// where a null input causes a no-op and returns null.
2126static llvm::Value *emitARCValueOperation(
2127 CodeGenFunction &CGF, llvm::Value *value, llvm::Type *returnType,
2128 llvm::Function *&fn, llvm::Intrinsic::ID IntID,
2129 llvm::CallInst::TailCallKind tailKind = llvm::CallInst::TCK_None) {
2130 if (isa<llvm::ConstantPointerNull>(value))
2131 return value;
2132
2133 if (!fn)
2134 fn = getARCIntrinsic(IntID, CGF.CGM);
2135
2136 // Cast the argument to 'id'.
2137 llvm::Type *origType = returnType ? returnType : value->getType();
2138 value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy);
2139
2140 // Call the function.
2141 llvm::CallInst *call = CGF.EmitNounwindRuntimeCall(fn, value);
2142 call->setTailCallKind(tailKind);
2143
2144 // Cast the result back to the original type.
2145 return CGF.Builder.CreateBitCast(call, origType);
2146}
2147
2148/// Perform an operation having the following signature:
2149/// i8* (i8**)
2150static llvm::Value *emitARCLoadOperation(CodeGenFunction &CGF, Address addr,
2151 llvm::Function *&fn,
2152 llvm::Intrinsic::ID IntID) {
2153 if (!fn)
2154 fn = getARCIntrinsic(IntID, CGF.CGM);
2155
2156 // Cast the argument to 'id*'.
2157 llvm::Type *origType = addr.getElementType();
2158 addr = CGF.Builder.CreateElementBitCast(addr, CGF.Int8PtrTy);
2159
2160 // Call the function.
2161 llvm::Value *result = CGF.EmitNounwindRuntimeCall(fn, addr.getPointer());
2162
2163 // Cast the result back to a dereference of the original type.
2164 if (origType != CGF.Int8PtrTy)
2165 result = CGF.Builder.CreateBitCast(result, origType);
2166
2167 return result;
2168}
2169
2170/// Perform an operation having the following signature:
2171/// i8* (i8**, i8*)
2172static llvm::Value *emitARCStoreOperation(CodeGenFunction &CGF, Address addr,
2173 llvm::Value *value,
2174 llvm::Function *&fn,
2175 llvm::Intrinsic::ID IntID,
2176 bool ignored) {
2177 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", 2177, __extension__ __PRETTY_FUNCTION__
))
;
2178
2179 if (!fn)
2180 fn = getARCIntrinsic(IntID, CGF.CGM);
2181
2182 llvm::Type *origType = value->getType();
2183
2184 llvm::Value *args[] = {
2185 CGF.Builder.CreateBitCast(addr.getPointer(), CGF.Int8PtrPtrTy),
2186 CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy)
2187 };
2188 llvm::CallInst *result = CGF.EmitNounwindRuntimeCall(fn, args);
2189
2190 if (ignored) return nullptr;
2191
2192 return CGF.Builder.CreateBitCast(result, origType);
2193}
2194
2195/// Perform an operation having the following signature:
2196/// void (i8**, i8**)
2197static void emitARCCopyOperation(CodeGenFunction &CGF, Address dst, Address src,
2198 llvm::Function *&fn,
2199 llvm::Intrinsic::ID IntID) {
2200 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"
, 2200, __extension__ __PRETTY_FUNCTION__))
;
2201
2202 if (!fn)
2203 fn = getARCIntrinsic(IntID, CGF.CGM);
2204
2205 llvm::Value *args[] = {
2206 CGF.Builder.CreateBitCast(dst.getPointer(), CGF.Int8PtrPtrTy),
2207 CGF.Builder.CreateBitCast(src.getPointer(), CGF.Int8PtrPtrTy)
2208 };
2209 CGF.EmitNounwindRuntimeCall(fn, args);
2210}
2211
2212/// Perform an operation having the signature
2213/// i8* (i8*)
2214/// where a null input causes a no-op and returns null.
2215static llvm::Value *emitObjCValueOperation(CodeGenFunction &CGF,
2216 llvm::Value *value,
2217 llvm::Type *returnType,
2218 llvm::FunctionCallee &fn,
2219 StringRef fnName) {
2220 if (isa<llvm::ConstantPointerNull>(value))
2221 return value;
2222
2223 if (!fn) {
2224 llvm::FunctionType *fnType =
2225 llvm::FunctionType::get(CGF.Int8PtrTy, CGF.Int8PtrTy, false);
2226 fn = CGF.CGM.CreateRuntimeFunction(fnType, fnName);
2227
2228 // We have Native ARC, so set nonlazybind attribute for performance
2229 if (llvm::Function *f = dyn_cast<llvm::Function>(fn.getCallee()))
2230 if (fnName == "objc_retain")
2231 f->addFnAttr(llvm::Attribute::NonLazyBind);
2232 }
2233
2234 // Cast the argument to 'id'.
2235 llvm::Type *origType = returnType ? returnType : value->getType();
2236 value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy);
2237
2238 // Call the function.
2239 llvm::CallBase *Inst = CGF.EmitCallOrInvoke(fn, value);
2240
2241 // Mark calls to objc_autorelease as tail on the assumption that methods
2242 // overriding autorelease do not touch anything on the stack.
2243 if (fnName == "objc_autorelease")
2244 if (auto *Call = dyn_cast<llvm::CallInst>(Inst))
2245 Call->setTailCall();
2246
2247 // Cast the result back to the original type.
2248 return CGF.Builder.CreateBitCast(Inst, origType);
2249}
2250
2251/// Produce the code to do a retain. Based on the type, calls one of:
2252/// call i8* \@objc_retain(i8* %value)
2253/// call i8* \@objc_retainBlock(i8* %value)
2254llvm::Value *CodeGenFunction::EmitARCRetain(QualType type, llvm::Value *value) {
2255 if (type->isBlockPointerType())
2256 return EmitARCRetainBlock(value, /*mandatory*/ false);
2257 else
2258 return EmitARCRetainNonBlock(value);
2259}
2260
2261/// Retain the given object, with normal retain semantics.
2262/// call i8* \@objc_retain(i8* %value)
2263llvm::Value *CodeGenFunction::EmitARCRetainNonBlock(llvm::Value *value) {
2264 return emitARCValueOperation(*this, value, nullptr,
2265 CGM.getObjCEntrypoints().objc_retain,
2266 llvm::Intrinsic::objc_retain);
2267}
2268
2269/// Retain the given block, with _Block_copy semantics.
2270/// call i8* \@objc_retainBlock(i8* %value)
2271///
2272/// \param mandatory - If false, emit the call with metadata
2273/// indicating that it's okay for the optimizer to eliminate this call
2274/// if it can prove that the block never escapes except down the stack.
2275llvm::Value *CodeGenFunction::EmitARCRetainBlock(llvm::Value *value,
2276 bool mandatory) {
2277 llvm::Value *result
2278 = emitARCValueOperation(*this, value, nullptr,
2279 CGM.getObjCEntrypoints().objc_retainBlock,
2280 llvm::Intrinsic::objc_retainBlock);
2281
2282 // If the copy isn't mandatory, add !clang.arc.copy_on_escape to
2283 // tell the optimizer that it doesn't need to do this copy if the
2284 // block doesn't escape, where being passed as an argument doesn't
2285 // count as escaping.
2286 if (!mandatory && isa<llvm::Instruction>(result)) {
2287 llvm::CallInst *call
2288 = cast<llvm::CallInst>(result->stripPointerCasts());
2289 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", 2290, __extension__ __PRETTY_FUNCTION__
))
2290 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", 2290, __extension__ __PRETTY_FUNCTION__
))
;
2291
2292 call->setMetadata("clang.arc.copy_on_escape",
2293 llvm::MDNode::get(Builder.getContext(), None));
2294 }
2295
2296 return result;
2297}
2298
2299static void emitAutoreleasedReturnValueMarker(CodeGenFunction &CGF) {
2300 // Fetch the void(void) inline asm which marks that we're going to
2301 // do something with the autoreleased return value.
2302 llvm::InlineAsm *&marker
2303 = CGF.CGM.getObjCEntrypoints().retainAutoreleasedReturnValueMarker;
2304 if (!marker) {
2305 StringRef assembly
2306 = CGF.CGM.getTargetCodeGenInfo()
2307 .getARCRetainAutoreleasedReturnValueMarker();
2308
2309 // If we have an empty assembly string, there's nothing to do.
2310 if (assembly.empty()) {
2311
2312 // Otherwise, at -O0, build an inline asm that we're going to call
2313 // in a moment.
2314 } else if (CGF.CGM.getCodeGenOpts().OptimizationLevel == 0) {
2315 llvm::FunctionType *type =
2316 llvm::FunctionType::get(CGF.VoidTy, /*variadic*/false);
2317
2318 marker = llvm::InlineAsm::get(type, assembly, "", /*sideeffects*/ true);
2319
2320 // If we're at -O1 and above, we don't want to litter the code
2321 // with this marker yet, so leave a breadcrumb for the ARC
2322 // optimizer to pick up.
2323 } else {
2324 const char *retainRVMarkerKey = llvm::objcarc::getRVMarkerModuleFlagStr();
2325 if (!CGF.CGM.getModule().getModuleFlag(retainRVMarkerKey)) {
2326 auto *str = llvm::MDString::get(CGF.getLLVMContext(), assembly);
2327 CGF.CGM.getModule().addModuleFlag(llvm::Module::Error,
2328 retainRVMarkerKey, str);
2329 }
2330 }
2331 }
2332
2333 // Call the marker asm if we made one, which we do only at -O0.
2334 if (marker)
2335 CGF.Builder.CreateCall(marker, None, CGF.getBundlesForFunclet(marker));
2336}
2337
2338static llvm::Value *emitOptimizedARCReturnCall(llvm::Value *value,
2339 bool IsRetainRV,
2340 CodeGenFunction &CGF) {
2341 emitAutoreleasedReturnValueMarker(CGF);
2342
2343 // Add operand bundle "clang.arc.attachedcall" to the call instead of emitting
2344 // retainRV or claimRV calls in the IR. We currently do this only when the
2345 // optimization level isn't -O0 since global-isel, which is currently run at
2346 // -O0, doesn't know about the operand bundle.
2347 ObjCEntrypoints &EPs = CGF.CGM.getObjCEntrypoints();
2348 llvm::Function *&EP = IsRetainRV
2349 ? EPs.objc_retainAutoreleasedReturnValue
2350 : EPs.objc_unsafeClaimAutoreleasedReturnValue;
2351 llvm::Intrinsic::ID IID =
2352 IsRetainRV ? llvm::Intrinsic::objc_retainAutoreleasedReturnValue
2353 : llvm::Intrinsic::objc_unsafeClaimAutoreleasedReturnValue;
2354 EP = getARCIntrinsic(IID, CGF.CGM);
2355
2356 llvm::Triple::ArchType Arch = CGF.CGM.getTriple().getArch();
2357
2358 // FIXME: Do this on all targets and at -O0 too. This can be enabled only if
2359 // the target backend knows how to handle the operand bundle.
2360 if (CGF.CGM.getCodeGenOpts().OptimizationLevel > 0 &&
2361 (Arch == llvm::Triple::aarch64 || Arch == llvm::Triple::x86_64)) {
2362 llvm::Value *bundleArgs[] = {EP};
2363 llvm::OperandBundleDef OB("clang.arc.attachedcall", bundleArgs);
2364 auto *oldCall = cast<llvm::CallBase>(value);
2365 llvm::CallBase *newCall = llvm::CallBase::addOperandBundle(
2366 oldCall, llvm::LLVMContext::OB_clang_arc_attachedcall, OB, oldCall);
2367 newCall->copyMetadata(*oldCall);
2368 oldCall->replaceAllUsesWith(newCall);
2369 oldCall->eraseFromParent();
2370 CGF.EmitARCNoopIntrinsicUse(newCall);
2371 return newCall;
2372 }
2373
2374 bool isNoTail =
2375 CGF.CGM.getTargetCodeGenInfo().markARCOptimizedReturnCallsAsNoTail();
2376 llvm::CallInst::TailCallKind tailKind =
2377 isNoTail ? llvm::CallInst::TCK_NoTail : llvm::CallInst::TCK_None;
2378 return emitARCValueOperation(CGF, value, nullptr, EP, IID, tailKind);
2379}
2380
2381/// Retain the given object which is the result of a function call.
2382/// call i8* \@objc_retainAutoreleasedReturnValue(i8* %value)
2383///
2384/// Yes, this function name is one character away from a different
2385/// call with completely different semantics.
2386llvm::Value *
2387CodeGenFunction::EmitARCRetainAutoreleasedReturnValue(llvm::Value *value) {
2388 return emitOptimizedARCReturnCall(value, true, *this);
2389}
2390
2391/// Claim a possibly-autoreleased return value at +0. This is only
2392/// valid to do in contexts which do not rely on the retain to keep
2393/// the object valid for all of its uses; for example, when
2394/// the value is ignored, or when it is being assigned to an
2395/// __unsafe_unretained variable.
2396///
2397/// call i8* \@objc_unsafeClaimAutoreleasedReturnValue(i8* %value)
2398llvm::Value *
2399CodeGenFunction::EmitARCUnsafeClaimAutoreleasedReturnValue(llvm::Value *value) {
2400 return emitOptimizedARCReturnCall(value, false, *this);
2401}
2402
2403/// Release the given object.
2404/// call void \@objc_release(i8* %value)
2405void CodeGenFunction::EmitARCRelease(llvm::Value *value,
2406 ARCPreciseLifetime_t precise) {
2407 if (isa<llvm::ConstantPointerNull>(value)) return;
2408
2409 llvm::Function *&fn = CGM.getObjCEntrypoints().objc_release;
2410 if (!fn)
2411 fn = getARCIntrinsic(llvm::Intrinsic::objc_release, CGM);
2412
2413 // Cast the argument to 'id'.
2414 value = Builder.CreateBitCast(value, Int8PtrTy);
2415
2416 // Call objc_release.
2417 llvm::CallInst *call = EmitNounwindRuntimeCall(fn, value);
2418
2419 if (precise == ARCImpreciseLifetime) {
2420 call->setMetadata("clang.imprecise_release",
2421 llvm::MDNode::get(Builder.getContext(), None));
2422 }
2423}
2424
2425/// Destroy a __strong variable.
2426///
2427/// At -O0, emit a call to store 'null' into the address;
2428/// instrumenting tools prefer this because the address is exposed,
2429/// but it's relatively cumbersome to optimize.
2430///
2431/// At -O1 and above, just load and call objc_release.
2432///
2433/// call void \@objc_storeStrong(i8** %addr, i8* null)
2434void CodeGenFunction::EmitARCDestroyStrong(Address addr,
2435 ARCPreciseLifetime_t precise) {
2436 if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
2437 llvm::Value *null = getNullForVariable(addr);
2438 EmitARCStoreStrongCall(addr, null, /*ignored*/ true);
2439 return;
2440 }
2441
2442 llvm::Value *value = Builder.CreateLoad(addr);
2443 EmitARCRelease(value, precise);
2444}
2445
2446/// Store into a strong object. Always calls this:
2447/// call void \@objc_storeStrong(i8** %addr, i8* %value)
2448llvm::Value *CodeGenFunction::EmitARCStoreStrongCall(Address addr,
2449 llvm::Value *value,
2450 bool ignored) {
2451 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", 2451, __extension__ __PRETTY_FUNCTION__
))
;
2452
2453 llvm::Function *&fn = CGM.getObjCEntrypoints().objc_storeStrong;
2454 if (!fn)
2455 fn = getARCIntrinsic(llvm::Intrinsic::objc_storeStrong, CGM);
2456
2457 llvm::Value *args[] = {
2458 Builder.CreateBitCast(addr.getPointer(), Int8PtrPtrTy),
2459 Builder.CreateBitCast(value, Int8PtrTy)
2460 };
2461 EmitNounwindRuntimeCall(fn, args);
2462
2463 if (ignored) return nullptr;
2464 return value;
2465}
2466
2467/// Store into a strong object. Sometimes calls this:
2468/// call void \@objc_storeStrong(i8** %addr, i8* %value)
2469/// Other times, breaks it down into components.
2470llvm::Value *CodeGenFunction::EmitARCStoreStrong(LValue dst,
2471 llvm::Value *newValue,
2472 bool ignored) {
2473 QualType type = dst.getType();
2474 bool isBlock = type->isBlockPointerType();
2475
2476 // Use a store barrier at -O0 unless this is a block type or the
2477 // lvalue is inadequately aligned.
2478 if (shouldUseFusedARCCalls() &&
2479 !isBlock &&
2480 (dst.getAlignment().isZero() ||
2481 dst.getAlignment() >= CharUnits::fromQuantity(PointerAlignInBytes))) {
2482 return EmitARCStoreStrongCall(dst.getAddress(*this), newValue, ignored);
2483 }
2484
2485 // Otherwise, split it out.
2486
2487 // Retain the new value.
2488 newValue = EmitARCRetain(type, newValue);
2489
2490 // Read the old value.
2491 llvm::Value *oldValue = EmitLoadOfScalar(dst, SourceLocation());
2492
2493 // Store. We do this before the release so that any deallocs won't
2494 // see the old value.
2495 EmitStoreOfScalar(newValue, dst);
2496
2497 // Finally, release the old value.
2498 EmitARCRelease(oldValue, dst.isARCPreciseLifetime());
2499
2500 return newValue;
2501}
2502
2503/// Autorelease the given object.
2504/// call i8* \@objc_autorelease(i8* %value)
2505llvm::Value *CodeGenFunction::EmitARCAutorelease(llvm::Value *value) {
2506 return emitARCValueOperation(*this, value, nullptr,
2507 CGM.getObjCEntrypoints().objc_autorelease,
2508 llvm::Intrinsic::objc_autorelease);
2509}
2510
2511/// Autorelease the given object.
2512/// call i8* \@objc_autoreleaseReturnValue(i8* %value)
2513llvm::Value *
2514CodeGenFunction::EmitARCAutoreleaseReturnValue(llvm::Value *value) {
2515 return emitARCValueOperation(*this, value, nullptr,
2516 CGM.getObjCEntrypoints().objc_autoreleaseReturnValue,
2517 llvm::Intrinsic::objc_autoreleaseReturnValue,
2518 llvm::CallInst::TCK_Tail);
2519}
2520
2521/// Do a fused retain/autorelease of the given object.
2522/// call i8* \@objc_retainAutoreleaseReturnValue(i8* %value)
2523llvm::Value *
2524CodeGenFunction::EmitARCRetainAutoreleaseReturnValue(llvm::Value *value) {
2525 return emitARCValueOperation(*this, value, nullptr,
2526 CGM.getObjCEntrypoints().objc_retainAutoreleaseReturnValue,
2527 llvm::Intrinsic::objc_retainAutoreleaseReturnValue,
2528 llvm::CallInst::TCK_Tail);
2529}
2530
2531/// Do a fused retain/autorelease of the given object.
2532/// call i8* \@objc_retainAutorelease(i8* %value)
2533/// or
2534/// %retain = call i8* \@objc_retainBlock(i8* %value)
2535/// call i8* \@objc_autorelease(i8* %retain)
2536llvm::Value *CodeGenFunction::EmitARCRetainAutorelease(QualType type,
2537 llvm::Value *value) {
2538 if (!type->isBlockPointerType())
2539 return EmitARCRetainAutoreleaseNonBlock(value);
2540
2541 if (isa<llvm::ConstantPointerNull>(value)) return value;
2542
2543 llvm::Type *origType = value->getType();
2544 value = Builder.CreateBitCast(value, Int8PtrTy);
2545 value = EmitARCRetainBlock(value, /*mandatory*/ true);
2546 value = EmitARCAutorelease(value);
2547 return Builder.CreateBitCast(value, origType);
2548}
2549
2550/// Do a fused retain/autorelease of the given object.
2551/// call i8* \@objc_retainAutorelease(i8* %value)
2552llvm::Value *
2553CodeGenFunction::EmitARCRetainAutoreleaseNonBlock(llvm::Value *value) {
2554 return emitARCValueOperation(*this, value, nullptr,
2555 CGM.getObjCEntrypoints().objc_retainAutorelease,
2556 llvm::Intrinsic::objc_retainAutorelease);
2557}
2558
2559/// i8* \@objc_loadWeak(i8** %addr)
2560/// Essentially objc_autorelease(objc_loadWeakRetained(addr)).
2561llvm::Value *CodeGenFunction::EmitARCLoadWeak(Address addr) {
2562 return emitARCLoadOperation(*this, addr,
2563 CGM.getObjCEntrypoints().objc_loadWeak,
2564 llvm::Intrinsic::objc_loadWeak);
2565}
2566
2567/// i8* \@objc_loadWeakRetained(i8** %addr)
2568llvm::Value *CodeGenFunction::EmitARCLoadWeakRetained(Address addr) {
2569 return emitARCLoadOperation(*this, addr,
2570 CGM.getObjCEntrypoints().objc_loadWeakRetained,
2571 llvm::Intrinsic::objc_loadWeakRetained);
2572}
2573
2574/// i8* \@objc_storeWeak(i8** %addr, i8* %value)
2575/// Returns %value.
2576llvm::Value *CodeGenFunction::EmitARCStoreWeak(Address addr,
2577 llvm::Value *value,
2578 bool ignored) {
2579 return emitARCStoreOperation(*this, addr, value,
2580 CGM.getObjCEntrypoints().objc_storeWeak,
2581 llvm::Intrinsic::objc_storeWeak, ignored);
2582}
2583
2584/// i8* \@objc_initWeak(i8** %addr, i8* %value)
2585/// Returns %value. %addr is known to not have a current weak entry.
2586/// Essentially equivalent to:
2587/// *addr = nil; objc_storeWeak(addr, value);
2588void CodeGenFunction::EmitARCInitWeak(Address addr, llvm::Value *value) {
2589 // If we're initializing to null, just write null to memory; no need
2590 // to get the runtime involved. But don't do this if optimization
2591 // is enabled, because accounting for this would make the optimizer
2592 // much more complicated.
2593 if (isa<llvm::ConstantPointerNull>(value) &&
2594 CGM.getCodeGenOpts().OptimizationLevel == 0) {
2595 Builder.CreateStore(value, addr);
2596 return;
2597 }
2598
2599 emitARCStoreOperation(*this, addr, value,
2600 CGM.getObjCEntrypoints().objc_initWeak,
2601 llvm::Intrinsic::objc_initWeak, /*ignored*/ true);
2602}
2603
2604/// void \@objc_destroyWeak(i8** %addr)
2605/// Essentially objc_storeWeak(addr, nil).
2606void CodeGenFunction::EmitARCDestroyWeak(Address addr) {
2607 llvm::Function *&fn = CGM.getObjCEntrypoints().objc_destroyWeak;
2608 if (!fn)
2609 fn = getARCIntrinsic(llvm::Intrinsic::objc_destroyWeak, CGM);
2610
2611 // Cast the argument to 'id*'.
2612 addr = Builder.CreateElementBitCast(addr, Int8PtrTy);
2613
2614 EmitNounwindRuntimeCall(fn, addr.getPointer());
2615}
2616
2617/// void \@objc_moveWeak(i8** %dest, i8** %src)
2618/// Disregards the current value in %dest. Leaves %src pointing to nothing.
2619/// Essentially (objc_copyWeak(dest, src), objc_destroyWeak(src)).
2620void CodeGenFunction::EmitARCMoveWeak(Address dst, Address src) {
2621 emitARCCopyOperation(*this, dst, src,
2622 CGM.getObjCEntrypoints().objc_moveWeak,
2623 llvm::Intrinsic::objc_moveWeak);
2624}
2625
2626/// void \@objc_copyWeak(i8** %dest, i8** %src)
2627/// Disregards the current value in %dest. Essentially
2628/// objc_release(objc_initWeak(dest, objc_readWeakRetained(src)))
2629void CodeGenFunction::EmitARCCopyWeak(Address dst, Address src) {
2630 emitARCCopyOperation(*this, dst, src,
2631 CGM.getObjCEntrypoints().objc_copyWeak,
2632 llvm::Intrinsic::objc_copyWeak);
2633}
2634
2635void CodeGenFunction::emitARCCopyAssignWeak(QualType Ty, Address DstAddr,
2636 Address SrcAddr) {
2637 llvm::Value *Object = EmitARCLoadWeakRetained(SrcAddr);
2638 Object = EmitObjCConsumeObject(Ty, Object);
2639 EmitARCStoreWeak(DstAddr, Object, false);
2640}
2641
2642void CodeGenFunction::emitARCMoveAssignWeak(QualType Ty, Address DstAddr,
2643 Address SrcAddr) {
2644 llvm::Value *Object = EmitARCLoadWeakRetained(SrcAddr);
2645 Object = EmitObjCConsumeObject(Ty, Object);
2646 EmitARCStoreWeak(DstAddr, Object, false);
2647 EmitARCDestroyWeak(SrcAddr);
2648}
2649
2650/// Produce the code to do a objc_autoreleasepool_push.
2651/// call i8* \@objc_autoreleasePoolPush(void)
2652llvm::Value *CodeGenFunction::EmitObjCAutoreleasePoolPush() {
2653 llvm::Function *&fn = CGM.getObjCEntrypoints().objc_autoreleasePoolPush;
2654 if (!fn)
2655 fn = getARCIntrinsic(llvm::Intrinsic::objc_autoreleasePoolPush, CGM);
2656
2657 return EmitNounwindRuntimeCall(fn);
2658}
2659
2660/// Produce the code to do a primitive release.
2661/// call void \@objc_autoreleasePoolPop(i8* %ptr)
2662void CodeGenFunction::EmitObjCAutoreleasePoolPop(llvm::Value *value) {
2663 assert(value->getType() == Int8PtrTy)(static_cast <bool> (value->getType() == Int8PtrTy) ?
void (0) : __assert_fail ("value->getType() == Int8PtrTy"
, "clang/lib/CodeGen/CGObjC.cpp", 2663, __extension__ __PRETTY_FUNCTION__
))
;
2664
2665 if (getInvokeDest()) {
2666 // Call the runtime method not the intrinsic if we are handling exceptions
2667 llvm::FunctionCallee &fn =
2668 CGM.getObjCEntrypoints().objc_autoreleasePoolPopInvoke;
2669 if (!fn) {
2670 llvm::FunctionType *fnType =
2671 llvm::FunctionType::get(Builder.getVoidTy(), Int8PtrTy, false);
2672 fn = CGM.CreateRuntimeFunction(fnType, "objc_autoreleasePoolPop");
2673 setARCRuntimeFunctionLinkage(CGM, fn);
2674 }
2675
2676 // objc_autoreleasePoolPop can throw.
2677 EmitRuntimeCallOrInvoke(fn, value);
2678 } else {
2679 llvm::FunctionCallee &fn = CGM.getObjCEntrypoints().objc_autoreleasePoolPop;
2680 if (!fn)
2681 fn = getARCIntrinsic(llvm::Intrinsic::objc_autoreleasePoolPop, CGM);
2682
2683 EmitRuntimeCall(fn, value);
2684 }
2685}
2686
2687/// Produce the code to do an MRR version objc_autoreleasepool_push.
2688/// Which is: [[NSAutoreleasePool alloc] init];
2689/// Where alloc is declared as: + (id) alloc; in NSAutoreleasePool class.
2690/// init is declared as: - (id) init; in its NSObject super class.
2691///
2692llvm::Value *CodeGenFunction::EmitObjCMRRAutoreleasePoolPush() {
2693 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
2694 llvm::Value *Receiver = Runtime.EmitNSAutoreleasePoolClassRef(*this);
2695 // [NSAutoreleasePool alloc]
2696 IdentifierInfo *II = &CGM.getContext().Idents.get("alloc");
2697 Selector AllocSel = getContext().Selectors.getSelector(0, &II);
2698 CallArgList Args;
2699 RValue AllocRV =
2700 Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
2701 getContext().getObjCIdType(),
2702 AllocSel, Receiver, Args);
2703
2704 // [Receiver init]
2705 Receiver = AllocRV.getScalarVal();
2706 II = &CGM.getContext().Idents.get("init");
2707 Selector InitSel = getContext().Selectors.getSelector(0, &II);
2708 RValue InitRV =
2709 Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
2710 getContext().getObjCIdType(),
2711 InitSel, Receiver, Args);
2712 return InitRV.getScalarVal();
2713}
2714
2715/// Allocate the given objc object.
2716/// call i8* \@objc_alloc(i8* %value)
2717llvm::Value *CodeGenFunction::EmitObjCAlloc(llvm::Value *value,
2718 llvm::Type *resultType) {
2719 return emitObjCValueOperation(*this, value, resultType,
2720 CGM.getObjCEntrypoints().objc_alloc,
2721 "objc_alloc");
2722}
2723
2724/// Allocate the given objc object.
2725/// call i8* \@objc_allocWithZone(i8* %value)
2726llvm::Value *CodeGenFunction::EmitObjCAllocWithZone(llvm::Value *value,
2727 llvm::Type *resultType) {
2728 return emitObjCValueOperation(*this, value, resultType,
2729 CGM.getObjCEntrypoints().objc_allocWithZone,
2730 "objc_allocWithZone");
2731}
2732
2733llvm::Value *CodeGenFunction::EmitObjCAllocInit(llvm::Value *value,
2734 llvm::Type *resultType) {
2735 return emitObjCValueOperation(*this, value, resultType,
2736 CGM.getObjCEntrypoints().objc_alloc_init,
2737 "objc_alloc_init");
2738}
2739
2740/// Produce the code to do a primitive release.
2741/// [tmp drain];
2742void CodeGenFunction::EmitObjCMRRAutoreleasePoolPop(llvm::Value *Arg) {
2743 IdentifierInfo *II = &CGM.getContext().Idents.get("drain");
2744 Selector DrainSel = getContext().Selectors.getSelector(0, &II);
2745 CallArgList Args;
2746 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
2747 getContext().VoidTy, DrainSel, Arg, Args);
2748}
2749
2750void CodeGenFunction::destroyARCStrongPrecise(CodeGenFunction &CGF,
2751 Address addr,
2752 QualType type) {
2753 CGF.EmitARCDestroyStrong(addr, ARCPreciseLifetime);
2754}
2755
2756void CodeGenFunction::destroyARCStrongImprecise(CodeGenFunction &CGF,
2757 Address addr,
2758 QualType type) {
2759 CGF.EmitARCDestroyStrong(addr, ARCImpreciseLifetime);
2760}
2761
2762void CodeGenFunction::destroyARCWeak(CodeGenFunction &CGF,
2763 Address addr,
2764 QualType type) {
2765 CGF.EmitARCDestroyWeak(addr);
2766}
2767
2768void CodeGenFunction::emitARCIntrinsicUse(CodeGenFunction &CGF, Address addr,
2769 QualType type) {
2770 llvm::Value *value = CGF.Builder.CreateLoad(addr);
2771 CGF.EmitARCIntrinsicUse(value);
2772}
2773
2774/// Autorelease the given object.
2775/// call i8* \@objc_autorelease(i8* %value)
2776llvm::Value *CodeGenFunction::EmitObjCAutorelease(llvm::Value *value,
2777 llvm::Type *returnType) {
2778 return emitObjCValueOperation(
2779 *this, value, returnType,
2780 CGM.getObjCEntrypoints().objc_autoreleaseRuntimeFunction,
2781 "objc_autorelease");
2782}
2783
2784/// Retain the given object, with normal retain semantics.
2785/// call i8* \@objc_retain(i8* %value)
2786llvm::Value *CodeGenFunction::EmitObjCRetainNonBlock(llvm::Value *value,
2787 llvm::Type *returnType) {
2788 return emitObjCValueOperation(
2789 *this, value, returnType,
2790 CGM.getObjCEntrypoints().objc_retainRuntimeFunction, "objc_retain");
2791}
2792
2793/// Release the given object.
2794/// call void \@objc_release(i8* %value)
2795void CodeGenFunction::EmitObjCRelease(llvm::Value *value,
2796 ARCPreciseLifetime_t precise) {
2797 if (isa<llvm::ConstantPointerNull>(value)) return;
2798
2799 llvm::FunctionCallee &fn =
2800 CGM.getObjCEntrypoints().objc_releaseRuntimeFunction;
2801 if (!fn) {
2802 llvm::FunctionType *fnType =
2803 llvm::FunctionType::get(Builder.getVoidTy(), Int8PtrTy, false);
2804 fn = CGM.CreateRuntimeFunction(fnType, "objc_release");
2805 setARCRuntimeFunctionLinkage(CGM, fn);
2806 // We have Native ARC, so set nonlazybind attribute for performance
2807 if (llvm::Function *f = dyn_cast<llvm::Function>(fn.getCallee()))
2808 f->addFnAttr(llvm::Attribute::NonLazyBind);
2809 }
2810
2811 // Cast the argument to 'id'.
2812 value = Builder.CreateBitCast(value, Int8PtrTy);
2813
2814 // Call objc_release.
2815 llvm::CallBase *call = EmitCallOrInvoke(fn, value);
2816
2817 if (precise == ARCImpreciseLifetime) {
2818 call->setMetadata("clang.imprecise_release",
2819 llvm::MDNode::get(Builder.getContext(), None));
2820 }
2821}
2822
2823namespace {
2824 struct CallObjCAutoreleasePoolObject final : EHScopeStack::Cleanup {
2825 llvm::Value *Token;
2826
2827 CallObjCAutoreleasePoolObject(llvm::Value *token) : Token(token) {}
2828
2829 void Emit(CodeGenFunction &CGF, Flags flags) override {
2830 CGF.EmitObjCAutoreleasePoolPop(Token);
2831 }
2832 };
2833 struct CallObjCMRRAutoreleasePoolObject final : EHScopeStack::Cleanup {
2834 llvm::Value *Token;
2835
2836 CallObjCMRRAutoreleasePoolObject(llvm::Value *token) : Token(token) {}
2837
2838 void Emit(CodeGenFunction &CGF, Flags flags) override {
2839 CGF.EmitObjCMRRAutoreleasePoolPop(Token);
2840 }
2841 };
2842}
2843
2844void CodeGenFunction::EmitObjCAutoreleasePoolCleanup(llvm::Value *Ptr) {
2845 if (CGM.getLangOpts().ObjCAutoRefCount)
2846 EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, Ptr);
2847 else
2848 EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, Ptr);
2849}
2850
2851static bool shouldRetainObjCLifetime(Qualifiers::ObjCLifetime lifetime) {
2852 switch (lifetime) {
2853 case Qualifiers::OCL_None:
2854 case Qualifiers::OCL_ExplicitNone:
2855 case Qualifiers::OCL_Strong:
2856 case Qualifiers::OCL_Autoreleasing:
2857 return true;
2858
2859 case Qualifiers::OCL_Weak:
2860 return false;
2861 }
2862
2863 llvm_unreachable("impossible lifetime!")::llvm::llvm_unreachable_internal("impossible lifetime!", "clang/lib/CodeGen/CGObjC.cpp"
, 2863)
;
2864}
2865
2866static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF,
2867 LValue lvalue,
2868 QualType type) {
2869 llvm::Value *result;
2870 bool shouldRetain = shouldRetainObjCLifetime(type.getObjCLifetime());
2871 if (shouldRetain) {
2872 result = CGF.EmitLoadOfLValue(lvalue, SourceLocation()).getScalarVal();
2873 } else {
2874 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", 2874, __extension__ __PRETTY_FUNCTION__
))
;
2875 result = CGF.EmitARCLoadWeakRetained(lvalue.getAddress(CGF));
2876 }
2877 return TryEmitResult(result, !shouldRetain);
2878}
2879
2880static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF,
2881 const Expr *e) {
2882 e = e->IgnoreParens();
2883 QualType type = e->getType();
2884
2885 // If we're loading retained from a __strong xvalue, we can avoid
2886 // an extra retain/release pair by zeroing out the source of this
2887 // "move" operation.
2888 if (e->isXValue() &&
2889 !type.isConstQualified() &&
2890 type.getObjCLifetime() == Qualifiers::OCL_Strong) {
2891 // Emit the lvalue.
2892 LValue lv = CGF.EmitLValue(e);
2893
2894 // Load the object pointer.
2895 llvm::Value *result = CGF.EmitLoadOfLValue(lv,
2896 SourceLocation()).getScalarVal();
2897
2898 // Set the source pointer to NULL.
2899 CGF.EmitStoreOfScalar(getNullForVariable(lv.getAddress(CGF)), lv);
2900
2901 return TryEmitResult(result, true);
2902 }
2903
2904 // As a very special optimization, in ARC++, if the l-value is the
2905 // result of a non-volatile assignment, do a simple retain of the
2906 // result of the call to objc_storeWeak instead of reloading.
2907 if (CGF.getLangOpts().CPlusPlus &&
2908 !type.isVolatileQualified() &&
2909 type.getObjCLifetime() == Qualifiers::OCL_Weak &&
2910 isa<BinaryOperator>(e) &&
2911 cast<BinaryOperator>(e)->getOpcode() == BO_Assign)
2912 return TryEmitResult(CGF.EmitScalarExpr(e), false);
2913
2914 // Try to emit code for scalar constant instead of emitting LValue and
2915 // loading it because we are not guaranteed to have an l-value. One of such
2916 // cases is DeclRefExpr referencing non-odr-used constant-evaluated variable.
2917 if (const auto *decl_expr = dyn_cast<DeclRefExpr>(e)) {
2918 auto *DRE = const_cast<DeclRefExpr *>(decl_expr);
2919 if (CodeGenFunction::ConstantEmission constant = CGF.tryEmitAsConstant(DRE))
2920 return TryEmitResult(CGF.emitScalarConstant(constant, DRE),
2921 !shouldRetainObjCLifetime(type.getObjCLifetime()));
2922 }
2923
2924 return tryEmitARCRetainLoadOfScalar(CGF, CGF.EmitLValue(e), type);
2925}
2926
2927typedef llvm::function_ref<llvm::Value *(CodeGenFunction &CGF,
2928 llvm::Value *value)>
2929 ValueTransform;
2930
2931/// Insert code immediately after a call.
2932
2933// FIXME: We should find a way to emit the runtime call immediately
2934// after the call is emitted to eliminate the need for this function.
2935static llvm::Value *emitARCOperationAfterCall(CodeGenFunction &CGF,
2936 llvm::Value *value,
2937 ValueTransform doAfterCall,
2938 ValueTransform doFallback) {
2939 CGBuilderTy::InsertPoint ip = CGF.Builder.saveIP();
2940 auto *callBase = dyn_cast<llvm::CallBase>(value);
2941
2942 if (callBase && llvm::objcarc::hasAttachedCallOpBundle(callBase)) {
2943 // Fall back if the call base has operand bundle "clang.arc.attachedcall".
2944 value = doFallback(CGF, value);
2945 } else if (llvm::CallInst *call = dyn_cast<llvm::CallInst>(value)) {
2946 // Place the retain immediately following the call.
2947 CGF.Builder.SetInsertPoint(call->getParent(),
2948 ++llvm::BasicBlock::iterator(call));
2949 value = doAfterCall(CGF, value);
2950 } else if (llvm::InvokeInst *invoke = dyn_cast<llvm::InvokeInst>(value)) {
2951 // Place the retain at the beginning of the normal destination block.
2952 llvm::BasicBlock *BB = invoke->getNormalDest();
2953 CGF.Builder.SetInsertPoint(BB, BB->begin());
2954 value = doAfterCall(CGF, value);
2955
2956 // Bitcasts can arise because of related-result returns. Rewrite
2957 // the operand.
2958 } else if (llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(value)) {
2959 // Change the insert point to avoid emitting the fall-back call after the
2960 // bitcast.
2961 CGF.Builder.SetInsertPoint(bitcast->getParent(), bitcast->getIterator());
2962 llvm::Value *operand = bitcast->getOperand(0);
2963 operand = emitARCOperationAfterCall(CGF, operand, doAfterCall, doFallback);
2964 bitcast->setOperand(0, operand);
2965 value = bitcast;
2966 } else {
2967 auto *phi = dyn_cast<llvm::PHINode>(value);
2968 if (phi && phi->getNumIncomingValues() == 2 &&
2969 isa<llvm::ConstantPointerNull>(phi->getIncomingValue(1)) &&
2970 isa<llvm::CallBase>(phi->getIncomingValue(0))) {
2971 // Handle phi instructions that are generated when it's necessary to check
2972 // whether the receiver of a message is null.
2973 llvm::Value *inVal = phi->getIncomingValue(0);
2974 inVal = emitARCOperationAfterCall(CGF, inVal, doAfterCall, doFallback);
2975 phi->setIncomingValue(0, inVal);
2976 value = phi;
2977 } else {
2978 // Generic fall-back case.
2979 // Retain using the non-block variant: we never need to do a copy
2980 // of a block that's been returned to us.
2981 value = doFallback(CGF, value);
2982 }
2983 }
2984
2985 CGF.Builder.restoreIP(ip);
2986 return value;
2987}
2988
2989/// Given that the given expression is some sort of call (which does
2990/// not return retained), emit a retain following it.
2991static llvm::Value *emitARCRetainCallResult(CodeGenFunction &CGF,
2992 const Expr *e) {
2993 llvm::Value *value = CGF.EmitScalarExpr(e);
2994 return emitARCOperationAfterCall(CGF, value,
2995 [](CodeGenFunction &CGF, llvm::Value *value) {
2996 return CGF.EmitARCRetainAutoreleasedReturnValue(value);
2997 },
2998 [](CodeGenFunction &CGF, llvm::Value *value) {
2999 return CGF.EmitARCRetainNonBlock(value);
3000 });
3001}
3002
3003/// Given that the given expression is some sort of call (which does
3004/// not return retained), perform an unsafeClaim following it.
3005static llvm::Value *emitARCUnsafeClaimCallResult(CodeGenFunction &CGF,
3006 const Expr *e) {
3007 llvm::Value *value = CGF.EmitScalarExpr(e);
3008 return emitARCOperationAfterCall(CGF, value,
3009 [](CodeGenFunction &CGF, llvm::Value *value) {
3010 return CGF.EmitARCUnsafeClaimAutoreleasedReturnValue(value);
3011 },
3012 [](CodeGenFunction &CGF, llvm::Value *value) {
3013 return value;
3014 });
3015}
3016
3017llvm::Value *CodeGenFunction::EmitARCReclaimReturnedObject(const Expr *E,
3018 bool allowUnsafeClaim) {
3019 if (allowUnsafeClaim &&
3020 CGM.getLangOpts().ObjCRuntime.hasARCUnsafeClaimAutoreleasedReturnValue()) {
3021 return emitARCUnsafeClaimCallResult(*this, E);
3022 } else {
3023 llvm::Value *value = emitARCRetainCallResult(*this, E);
3024 return EmitObjCConsumeObject(E->getType(), value);
3025 }
3026}
3027
3028/// Determine whether it might be important to emit a separate
3029/// objc_retain_block on the result of the given expression, or
3030/// whether it's okay to just emit it in a +1 context.
3031static bool shouldEmitSeparateBlockRetain(const Expr *e) {
3032 assert(e->getType()->isBlockPointerType())(static_cast <bool> (e->getType()->isBlockPointerType
()) ? void (0) : __assert_fail ("e->getType()->isBlockPointerType()"
, "clang/lib/CodeGen/CGObjC.cpp", 3032, __extension__ __PRETTY_FUNCTION__
))
;
3033 e = e->IgnoreParens();
3034
3035 // For future goodness, emit block expressions directly in +1
3036 // contexts if we can.
3037 if (isa<BlockExpr>(e))
3038 return false;
3039
3040 if (const CastExpr *cast = dyn_cast<CastExpr>(e)) {
3041 switch (cast->getCastKind()) {
3042 // Emitting these operations in +1 contexts is goodness.
3043 case CK_LValueToRValue:
3044 case CK_ARCReclaimReturnedObject:
3045 case CK_ARCConsumeObject:
3046 case CK_ARCProduceObject:
3047 return false;
3048
3049 // These operations preserve a block type.
3050 case CK_NoOp:
3051 case CK_BitCast:
3052 return shouldEmitSeparateBlockRetain(cast->getSubExpr());
3053
3054 // These operations are known to be bad (or haven't been considered).
3055 case CK_AnyPointerToBlockPointerCast:
3056 default:
3057 return true;
3058 }
3059 }
3060
3061 return true;
3062}
3063
3064namespace {
3065/// A CRTP base class for emitting expressions of retainable object
3066/// pointer type in ARC.
3067template <typename Impl, typename Result> class ARCExprEmitter {
3068protected:
3069 CodeGenFunction &CGF;
3070 Impl &asImpl() { return *static_cast<Impl*>(this); }
3071
3072 ARCExprEmitter(CodeGenFunction &CGF) : CGF(CGF) {}
3073
3074public:
3075 Result visit(const Expr *e);
3076 Result visitCastExpr(const CastExpr *e);
3077 Result visitPseudoObjectExpr(const PseudoObjectExpr *e);
3078 Result visitBlockExpr(const BlockExpr *e);
3079 Result visitBinaryOperator(const BinaryOperator *e);
3080 Result visitBinAssign(const BinaryOperator *e);
3081 Result visitBinAssignUnsafeUnretained(const BinaryOperator *e);
3082 Result visitBinAssignAutoreleasing(const BinaryOperator *e);
3083 Result visitBinAssignWeak(const BinaryOperator *e);
3084 Result visitBinAssignStrong(const BinaryOperator *e);
3085
3086 // Minimal implementation:
3087 // Result visitLValueToRValue(const Expr *e)
3088 // Result visitConsumeObject(const Expr *e)
3089 // Result visitExtendBlockObject(const Expr *e)
3090 // Result visitReclaimReturnedObject(const Expr *e)
3091 // Result visitCall(const Expr *e)
3092 // Result visitExpr(const Expr *e)
3093 //
3094 // Result emitBitCast(Result result, llvm::Type *resultType)
3095 // llvm::Value *getValueOfResult(Result result)
3096};
3097}
3098
3099/// Try to emit a PseudoObjectExpr under special ARC rules.
3100///
3101/// This massively duplicates emitPseudoObjectRValue.
3102template <typename Impl, typename Result>
3103Result
3104ARCExprEmitter<Impl,Result>::visitPseudoObjectExpr(const PseudoObjectExpr *E) {
3105 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
3106
3107 // Find the result expression.
3108 const Expr *resultExpr = E->getResultExpr();
3109 assert(resultExpr)(static_cast <bool> (resultExpr) ? void (0) : __assert_fail
("resultExpr", "clang/lib/CodeGen/CGObjC.cpp", 3109, __extension__
__PRETTY_FUNCTION__))
;
18
Assuming 'resultExpr' is non-null
19
'?' condition is true
3110 Result result;
20
'result' declared without an initial value
3111
3112 for (PseudoObjectExpr::const_semantics_iterator
21
Loop condition is false. Execution continues on line 3148
3113 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
3114 const Expr *semantic = *i;
3115
3116 // If this semantic expression is an opaque value, bind it
3117 // to the result of its source expression.
3118 if (const OpaqueValueExpr *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
3119 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
3120 OVMA opaqueData;
3121
3122 // If this semantic is the result of the pseudo-object
3123 // expression, try to evaluate the source as +1.
3124 if (ov == resultExpr) {
3125 assert(!OVMA::shouldBindAsLValue(ov))(static_cast <bool> (!OVMA::shouldBindAsLValue(ov)) ? void
(0) : __assert_fail ("!OVMA::shouldBindAsLValue(ov)", "clang/lib/CodeGen/CGObjC.cpp"
, 3125, __extension__ __PRETTY_FUNCTION__))
;
3126 result = asImpl().visit(ov->getSourceExpr());
3127 opaqueData = OVMA::bind(CGF, ov,
3128 RValue::get(asImpl().getValueOfResult(result)));
3129
3130 // Otherwise, just bind it.
3131 } else {
3132 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
3133 }
3134 opaques.push_back(opaqueData);
3135
3136 // Otherwise, if the expression is the result, evaluate it
3137 // and remember the result.
3138 } else if (semantic == resultExpr) {
3139 result = asImpl().visit(semantic);
3140
3141 // Otherwise, evaluate the expression in an ignored context.
3142 } else {
3143 CGF.EmitIgnoredExpr(semantic);
3144 }
3145 }
3146
3147 // Unbind all the opaques now.
3148 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 3151
3149 opaques[i].unbind(CGF);
3150
3151 return result;
24
Undefined or garbage value returned to caller
3152}
3153
3154template <typename Impl, typename Result>
3155Result ARCExprEmitter<Impl, Result>::visitBlockExpr(const BlockExpr *e) {
3156 // The default implementation just forwards the expression to visitExpr.
3157 return asImpl().visitExpr(e);
3158}
3159
3160template <typename Impl, typename Result>
3161Result ARCExprEmitter<Impl,Result>::visitCastExpr(const CastExpr *e) {
3162 switch (e->getCastKind()) {
3163
3164 // No-op casts don't change the type, so we just ignore them.
3165 case CK_NoOp:
3166 return asImpl().visit(e->getSubExpr());
3167
3168 // These casts can change the type.
3169 case CK_CPointerToObjCPointerCast:
3170 case CK_BlockPointerToObjCPointerCast:
3171 case CK_AnyPointerToBlockPointerCast:
3172 case CK_BitCast: {
3173 llvm::Type *resultType = CGF.ConvertType(e->getType());
3174 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", 3174, __extension__ __PRETTY_FUNCTION__
))
;
3175 Result result = asImpl().visit(e->getSubExpr());
3176 return asImpl().emitBitCast(result, resultType);
3177 }
3178
3179 // Handle some casts specially.
3180 case CK_LValueToRValue:
3181 return asImpl().visitLValueToRValue(e->getSubExpr());
3182 case CK_ARCConsumeObject:
3183 return asImpl().visitConsumeObject(e->getSubExpr());
3184 case CK_ARCExtendBlockObject:
3185 return asImpl().visitExtendBlockObject(e->getSubExpr());
3186 case CK_ARCReclaimReturnedObject:
3187 return asImpl().visitReclaimReturnedObject(e->getSubExpr());
3188
3189 // Otherwise, use the default logic.
3190 default:
3191 return asImpl().visitExpr(e);
3192 }
3193}
3194
3195template <typename Impl, typename Result>
3196Result
3197ARCExprEmitter<Impl,Result>::visitBinaryOperator(const BinaryOperator *e) {
3198 switch (e->getOpcode()) {
3199 case BO_Comma:
3200 CGF.EmitIgnoredExpr(e->getLHS());
3201 CGF.EnsureInsertPoint();
3202 return asImpl().visit(e->getRHS());
3203
3204 case BO_Assign:
3205 return asImpl().visitBinAssign(e);
3206
3207 default:
3208 return asImpl().visitExpr(e);
3209 }
3210}
3211
3212template <typename Impl, typename Result>
3213Result ARCExprEmitter<Impl,Result>::visitBinAssign(const BinaryOperator *e) {
3214 switch (e->getLHS()->getType().getObjCLifetime()) {
3215 case Qualifiers::OCL_ExplicitNone:
3216 return asImpl().visitBinAssignUnsafeUnretained(e);
3217
3218 case Qualifiers::OCL_Weak:
3219 return asImpl().visitBinAssignWeak(e);
3220
3221 case Qualifiers::OCL_Autoreleasing:
3222 return asImpl().visitBinAssignAutoreleasing(e);
3223
3224 case Qualifiers::OCL_Strong:
3225 return asImpl().visitBinAssignStrong(e);
3226
3227 case Qualifiers::OCL_None:
3228 return asImpl().visitExpr(e);
3229 }
3230 llvm_unreachable("bad ObjC ownership qualifier")::llvm::llvm_unreachable_internal("bad ObjC ownership qualifier"
, "clang/lib/CodeGen/CGObjC.cpp", 3230)
;
3231}
3232
3233/// The default rule for __unsafe_unretained emits the RHS recursively,
3234/// stores into the unsafe variable, and propagates the result outward.
3235template <typename Impl, typename Result>
3236Result ARCExprEmitter<Impl,Result>::
3237 visitBinAssignUnsafeUnretained(const BinaryOperator *e) {
3238 // Recursively emit the RHS.
3239 // For __block safety, do this before emitting the LHS.
3240 Result result = asImpl().visit(e->getRHS());
3241
3242 // Perform the store.
3243 LValue lvalue =
3244 CGF.EmitCheckedLValue(e->getLHS(), CodeGenFunction::TCK_Store);
3245 CGF.EmitStoreThroughLValue(RValue::get(asImpl().getValueOfResult(result)),
3246 lvalue);
3247
3248 return result;
3249}
3250
3251template <typename Impl, typename Result>
3252Result
3253ARCExprEmitter<Impl,Result>::visitBinAssignAutoreleasing(const BinaryOperator *e) {
3254 return asImpl().visitExpr(e);
3255}
3256
3257template <typename Impl, typename Result>
3258Result
3259ARCExprEmitter<Impl,Result>::visitBinAssignWeak(const BinaryOperator *e) {
3260 return asImpl().visitExpr(e);
3261}
3262
3263template <typename Impl, typename Result>
3264Result
3265ARCExprEmitter<Impl,Result>::visitBinAssignStrong(const BinaryOperator *e) {
3266 return asImpl().visitExpr(e);
3267}
3268
3269/// The general expression-emission logic.
3270template <typename Impl, typename Result>
3271Result ARCExprEmitter<Impl,Result>::visit(const Expr *e) {
3272 // We should *never* see a nested full-expression here, because if
3273 // we fail to emit at +1, our caller must not retain after we close
3274 // out the full-expression. This isn't as important in the unsafe
3275 // emitter.
3276 assert(!isa<ExprWithCleanups>(e))(static_cast <bool> (!isa<ExprWithCleanups>(e)) ?
void (0) : __assert_fail ("!isa<ExprWithCleanups>(e)",
"clang/lib/CodeGen/CGObjC.cpp", 3276, __extension__ __PRETTY_FUNCTION__
))
;
8
'e' is not a 'ExprWithCleanups'
9
'?' condition is true
3277
3278 // Look through parens, __extension__, generic selection, etc.
3279 e = e->IgnoreParens();
3280
3281 // Handle certain kinds of casts.
3282 if (const CastExpr *ce
10.1
'ce' is null
= dyn_cast<CastExpr>(e)) {
10
Assuming 'e' is not a 'CastReturnType'
11
Taking false branch
3283 return asImpl().visitCastExpr(ce);
3284
3285 // Handle the comma operator.
3286 } else if (auto op
12.1
'op' is null
= dyn_cast<BinaryOperator>(e)) {
12
Assuming 'e' is not a 'CastReturnType'
3287 return asImpl().visitBinaryOperator(op);
3288
3289 // TODO: handle conditional operators here
3290
3291 // For calls and message sends, use the retained-call logic.
3292 // Delegate inits are a special case in that they're the only
3293 // returns-retained expression that *isn't* surrounded by
3294 // a consume.
3295 } else if (isa<CallExpr>(e) ||
13
Assuming 'e' is not a 'CallExpr'
3296 (isa<ObjCMessageExpr>(e) &&
14
Assuming 'e' is not a 'ObjCMessageExpr'
3297 !cast<ObjCMessageExpr>(e)->isDelegateInitCall())) {
3298 return asImpl().visitCall(e);
3299
3300 // Look through pseudo-object expressions.
3301 } 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
3302 return asImpl().visitPseudoObjectExpr(pseudo);
17
Calling 'ARCExprEmitter::visitPseudoObjectExpr'
3303 } else if (auto *be = dyn_cast<BlockExpr>(e))
3304 return asImpl().visitBlockExpr(be);
3305
3306 return asImpl().visitExpr(e);
3307}
3308
3309namespace {
3310
3311/// An emitter for +1 results.
3312struct ARCRetainExprEmitter :
3313 public ARCExprEmitter<ARCRetainExprEmitter, TryEmitResult> {
3314
3315 ARCRetainExprEmitter(CodeGenFunction &CGF) : ARCExprEmitter(CGF) {}
3316
3317 llvm::Value *getValueOfResult(TryEmitResult result) {
3318 return result.getPointer();
3319 }
3320
3321 TryEmitResult emitBitCast(TryEmitResult result, llvm::Type *resultType) {
3322 llvm::Value *value = result.getPointer();
3323 value = CGF.Builder.CreateBitCast(value, resultType);
3324 result.setPointer(value);
3325 return result;
3326 }
3327
3328 TryEmitResult visitLValueToRValue(const Expr *e) {
3329 return tryEmitARCRetainLoadOfScalar(CGF, e);
3330 }
3331
3332 /// For consumptions, just emit the subexpression and thus elide
3333 /// the retain/release pair.
3334 TryEmitResult visitConsumeObject(const Expr *e) {
3335 llvm::Value *result = CGF.EmitScalarExpr(e);
3336 return TryEmitResult(result, true);
3337 }
3338
3339 TryEmitResult visitBlockExpr(const BlockExpr *e) {
3340 TryEmitResult result = visitExpr(e);
3341 // Avoid the block-retain if this is a block literal that doesn't need to be
3342 // copied to the heap.
3343 if (CGF.CGM.getCodeGenOpts().ObjCAvoidHeapifyLocalBlocks &&
3344 e->getBlockDecl()->canAvoidCopyToHeap())
3345 result.setInt(true);
3346 return result;
3347 }
3348
3349 /// Block extends are net +0. Naively, we could just recurse on
3350 /// the subexpression, but actually we need to ensure that the
3351 /// value is copied as a block, so there's a little filter here.
3352 TryEmitResult visitExtendBlockObject(const Expr *e) {
3353 llvm::Value *result; // will be a +0 value
3354
3355 // If we can't safely assume the sub-expression will produce a
3356 // block-copied value, emit the sub-expression at +0.
3357 if (shouldEmitSeparateBlockRetain(e)) {
3358 result = CGF.EmitScalarExpr(e);
3359
3360 // Otherwise, try to emit the sub-expression at +1 recursively.
3361 } else {
3362 TryEmitResult subresult = asImpl().visit(e);
3363
3364 // If that produced a retained value, just use that.
3365 if (subresult.getInt()) {
3366 return subresult;
3367 }
3368
3369 // Otherwise it's +0.
3370 result = subresult.getPointer();
3371 }
3372
3373 // Retain the object as a block.
3374 result = CGF.EmitARCRetainBlock(result, /*mandatory*/ true);
3375 return TryEmitResult(result, true);
3376 }
3377
3378 /// For reclaims, emit the subexpression as a retained call and
3379 /// skip the consumption.
3380 TryEmitResult visitReclaimReturnedObject(const Expr *e) {
3381 llvm::Value *result = emitARCRetainCallResult(CGF, e);
3382 return TryEmitResult(result, true);
3383 }
3384
3385 /// When we have an undecorated call, retroactively do a claim.
3386 TryEmitResult visitCall(const Expr *e) {
3387 llvm::Value *result = emitARCRetainCallResult(CGF, e);
3388 return TryEmitResult(result, true);
3389 }
3390
3391 // TODO: maybe special-case visitBinAssignWeak?
3392
3393 TryEmitResult visitExpr(const Expr *e) {
3394 // We didn't find an obvious production, so emit what we've got and
3395 // tell the caller that we didn't manage to retain.
3396 llvm::Value *result = CGF.EmitScalarExpr(e);
3397 return TryEmitResult(result, false);
3398 }
3399};
3400}
3401
3402static TryEmitResult
3403tryEmitARCRetainScalarExpr(CodeGenFunction &CGF, const Expr *e) {
3404 return ARCRetainExprEmitter(CGF).visit(e);
3405}
3406
3407static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF,
3408 LValue lvalue,
3409 QualType type) {
3410 TryEmitResult result = tryEmitARCRetainLoadOfScalar(CGF, lvalue, type);
3411 llvm::Value *value = result.getPointer();
3412 if (!result.getInt())
3413 value = CGF.EmitARCRetain(type, value);
3414 return value;
3415}
3416
3417/// EmitARCRetainScalarExpr - Semantically equivalent to
3418/// EmitARCRetainObject(e->getType(), EmitScalarExpr(e)), but making a
3419/// best-effort attempt to peephole expressions that naturally produce
3420/// retained objects.
3421llvm::Value *CodeGenFunction::EmitARCRetainScalarExpr(const Expr *e) {
3422 // The retain needs to happen within the full-expression.
3423 if (const ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(e)) {
3424 RunCleanupsScope scope(*this);
3425 return EmitARCRetainScalarExpr(cleanups->getSubExpr());
3426 }
3427
3428 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e);
3429 llvm::Value *value = result.getPointer();
3430 if (!result.getInt())
3431 value = EmitARCRetain(e->getType(), value);
3432 return value;
3433}
3434
3435llvm::Value *
3436CodeGenFunction::EmitARCRetainAutoreleaseScalarExpr(const Expr *e) {
3437 // The retain needs to happen within the full-expression.
3438 if (const ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(e)) {
3439 RunCleanupsScope scope(*this);
3440 return EmitARCRetainAutoreleaseScalarExpr(cleanups->getSubExpr());
3441 }
3442
3443 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e);
3444 llvm::Value *value = result.getPointer();
3445 if (result.getInt())
3446 value = EmitARCAutorelease(value);
3447 else
3448 value = EmitARCRetainAutorelease(e->getType(), value);
3449 return value;
3450}
3451
3452llvm::Value *CodeGenFunction::EmitARCExtendBlockObject(const Expr *e) {
3453 llvm::Value *result;
3454 bool doRetain;
3455
3456 if (shouldEmitSeparateBlockRetain(e)) {
3457 result = EmitScalarExpr(e);
3458 doRetain = true;
3459 } else {
3460 TryEmitResult subresult = tryEmitARCRetainScalarExpr(*this, e);
3461 result = subresult.getPointer();
3462 doRetain = !subresult.getInt();
3463 }
3464
3465 if (doRetain)
3466 result = EmitARCRetainBlock(result, /*mandatory*/ true);
3467 return EmitObjCConsumeObject(e->getType(), result);
3468}
3469
3470llvm::Value *CodeGenFunction::EmitObjCThrowOperand(const Expr *expr) {
3471 // In ARC, retain and autorelease the expression.
3472 if (getLangOpts().ObjCAutoRefCount) {
3473 // Do so before running any cleanups for the full-expression.
3474 // EmitARCRetainAutoreleaseScalarExpr does this for us.
3475 return EmitARCRetainAutoreleaseScalarExpr(expr);
3476 }
3477
3478 // Otherwise, use the normal scalar-expression emission. The
3479 // exception machinery doesn't do anything special with the
3480 // exception like retaining it, so there's no safety associated with
3481 // only running cleanups after the throw has started, and when it
3482 // matters it tends to be substantially inferior code.
3483 return EmitScalarExpr(expr);
3484}
3485
3486namespace {
3487
3488/// An emitter for assigning into an __unsafe_unretained context.
3489struct ARCUnsafeUnretainedExprEmitter :
3490 public ARCExprEmitter<ARCUnsafeUnretainedExprEmitter, llvm::Value*> {
3491
3492 ARCUnsafeUnretainedExprEmitter(CodeGenFunction &CGF) : ARCExprEmitter(CGF) {}
3493
3494 llvm::Value *getValueOfResult(llvm::Value *value) {
3495 return value;
3496 }
3497
3498 llvm::Value *emitBitCast(llvm::Value *value, llvm::Type *resultType) {
3499 return CGF.Builder.CreateBitCast(value, resultType);
3500 }
3501
3502 llvm::Value *visitLValueToRValue(const Expr *e) {
3503 return CGF.EmitScalarExpr(e);
3504 }
3505
3506 /// For consumptions, just emit the subexpression and perform the
3507 /// consumption like normal.
3508 llvm::Value *visitConsumeObject(const Expr *e) {
3509 llvm::Value *value = CGF.EmitScalarExpr(e);
3510 return CGF.EmitObjCConsumeObject(e->getType(), value);
3511 }
3512
3513 /// No special logic for block extensions. (This probably can't
3514 /// actually happen in this emitter, though.)
3515 llvm::Value *visitExtendBlockObject(const Expr *e) {
3516 return CGF.EmitARCExtendBlockObject(e);
3517 }
3518
3519 /// For reclaims, perform an unsafeClaim if that's enabled.
3520 llvm::Value *visitReclaimReturnedObject(const Expr *e) {
3521 return CGF.EmitARCReclaimReturnedObject(e, /*unsafe*/ true);
3522 }
3523
3524 /// When we have an undecorated call, just emit it without adding
3525 /// the unsafeClaim.
3526 llvm::Value *visitCall(const Expr *e) {
3527 return CGF.EmitScalarExpr(e);
3528 }
3529
3530 /// Just do normal scalar emission in the default case.
3531 llvm::Value *visitExpr(const Expr *e) {
3532 return CGF.EmitScalarExpr(e);
3533 }
3534};
3535}
3536
3537static llvm::Value *emitARCUnsafeUnretainedScalarExpr(CodeGenFunction &CGF,
3538 const Expr *e) {
3539 return ARCUnsafeUnretainedExprEmitter(CGF).visit(e);
7
Calling 'ARCExprEmitter::visit'
3540}
3541
3542/// EmitARCUnsafeUnretainedScalarExpr - Semantically equivalent to
3543/// immediately releasing the resut of EmitARCRetainScalarExpr, but
3544/// avoiding any spurious retains, including by performing reclaims
3545/// with objc_unsafeClaimAutoreleasedReturnValue.
3546llvm::Value *CodeGenFunction::EmitARCUnsafeUnretainedScalarExpr(const Expr *e) {
3547 // Look through full-expressions.
3548 if (const ExprWithCleanups *cleanups
4.1
'cleanups' is null
= dyn_cast<ExprWithCleanups>(e)) {
4
Assuming 'e' is not a 'CastReturnType'
5
Taking false branch
3549 RunCleanupsScope scope(*this);
3550 return emitARCUnsafeUnretainedScalarExpr(*this, cleanups->getSubExpr());
3551 }
3552
3553 return emitARCUnsafeUnretainedScalarExpr(*this, e);
6
Calling 'emitARCUnsafeUnretainedScalarExpr'
3554}
3555
3556std::pair<LValue,llvm::Value*>
3557CodeGenFunction::EmitARCStoreUnsafeUnretained(const BinaryOperator *e,
3558 bool ignored) {
3559 // Evaluate the RHS first. If we're ignoring the result, assume
3560 // that we can emit at an unsafe +0.
3561 llvm::Value *value;
3562 if (ignored) {
1
Assuming 'ignored' is true
2
Taking true branch
3563 value = EmitARCUnsafeUnretainedScalarExpr(e->getRHS());
3
Calling 'CodeGenFunction::EmitARCUnsafeUnretainedScalarExpr'
3564 } else {
3565 value = EmitScalarExpr(e->getRHS());
3566 }
3567
3568 // Emit the LHS and perform the store.
3569 LValue lvalue = EmitLValue(e->getLHS());
3570 EmitStoreOfScalar(value, lvalue);
3571
3572 return std::pair<LValue,llvm::Value*>(std::move(lvalue), value);
3573}
3574
3575std::pair<LValue,llvm::Value*>
3576CodeGenFunction::EmitARCStoreStrong(const BinaryOperator *e,
3577 bool ignored) {
3578 // Evaluate the RHS first.
3579 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e->getRHS());
3580 llvm::Value *value = result.getPointer();
3581
3582 bool hasImmediateRetain = result.getInt();
3583
3584 // If we didn't emit a retained object, and the l-value is of block
3585 // type, then we need to emit the block-retain immediately in case
3586 // it invalidates the l-value.
3587 if (!hasImmediateRetain && e->getType()->isBlockPointerType()) {
3588 value = EmitARCRetainBlock(value, /*mandatory*/ false);
3589 hasImmediateRetain = true;
3590 }
3591
3592 LValue lvalue = EmitLValue(e->getLHS());
3593
3594 // If the RHS was emitted retained, expand this.
3595 if (hasImmediateRetain) {
3596 llvm::Value *oldValue = EmitLoadOfScalar(lvalue, SourceLocation());
3597 EmitStoreOfScalar(value, lvalue);
3598 EmitARCRelease(oldValue, lvalue.isARCPreciseLifetime());
3599 } else {
3600 value = EmitARCStoreStrong(lvalue, value, ignored);
3601 }
3602
3603 return std::pair<LValue,llvm::Value*>(lvalue, value);
3604}
3605
3606std::pair<LValue,llvm::Value*>
3607CodeGenFunction::EmitARCStoreAutoreleasing(const BinaryOperator *e) {
3608 llvm::Value *value = EmitARCRetainAutoreleaseScalarExpr(e->getRHS());
3609 LValue lvalue = EmitLValue(e->getLHS());
3610
3611 EmitStoreOfScalar(value, lvalue);
3612
3613 return std::pair<LValue,llvm::Value*>(lvalue, value);
3614}
3615
3616void CodeGenFunction::EmitObjCAutoreleasePoolStmt(
3617 const ObjCAutoreleasePoolStmt &ARPS) {
3618 const Stmt *subStmt = ARPS.getSubStmt();
3619 const CompoundStmt &S = cast<CompoundStmt>(*subStmt);
3620
3621 CGDebugInfo *DI = getDebugInfo();
3622 if (DI)
3623 DI->EmitLexicalBlockStart(Builder, S.getLBracLoc());
3624
3625 // Keep track of the current cleanup stack depth.
3626 RunCleanupsScope Scope(*this);
3627 if (CGM.getLangOpts().ObjCRuntime.hasNativeARC()) {
3628 llvm::Value *token = EmitObjCAutoreleasePoolPush();
3629 EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, token);
3630 } else {
3631 llvm::Value *token = EmitObjCMRRAutoreleasePoolPush();
3632 EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, token);
3633 }
3634
3635 for (const auto *I : S.body())
3636 EmitStmt(I);
3637
3638 if (DI)
3639 DI->EmitLexicalBlockEnd(Builder, S.getRBracLoc());
3640}
3641
3642/// EmitExtendGCLifetime - Given a pointer to an Objective-C object,
3643/// make sure it survives garbage collection until this point.
3644void CodeGenFunction::EmitExtendGCLifetime(llvm::Value *object) {
3645 // We just use an inline assembly.
3646 llvm::FunctionType *extenderType
3647 = llvm::FunctionType::get(VoidTy, VoidPtrTy, RequiredArgs::All);
3648 llvm::InlineAsm *extender = llvm::InlineAsm::get(extenderType,
3649 /* assembly */ "",
3650 /* constraints */ "r",
3651 /* side effects */ true);
3652
3653 object = Builder.CreateBitCast(object, VoidPtrTy);
3654 EmitNounwindRuntimeCall(extender, object);
3655}
3656
3657/// GenerateObjCAtomicSetterCopyHelperFunction - Given a c++ object type with
3658/// non-trivial copy assignment function, produce following helper function.
3659/// static void copyHelper(Ty *dest, const Ty *source) { *dest = *source; }
3660///
3661llvm::Constant *
3662CodeGenFunction::GenerateObjCAtomicSetterCopyHelperFunction(
3663 const ObjCPropertyImplDecl *PID) {
3664 if (!getLangOpts().CPlusPlus ||
3665 !getLangOpts().ObjCRuntime.hasAtomicCopyHelper())
3666 return nullptr;
3667 QualType Ty = PID->getPropertyIvarDecl()->getType();
3668 if (!Ty->isRecordType())
3669 return nullptr;
3670 const ObjCPropertyDecl *PD = PID->getPropertyDecl();
3671 if ((!(PD->getPropertyAttributes() & ObjCPropertyAttribute::kind_atomic)))
3672 return nullptr;
3673 llvm::Constant *HelperFn = nullptr;
3674 if (hasTrivialSetExpr(PID))
3675 return nullptr;
3676 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", 3676, __extension__ __PRETTY_FUNCTION__
))
;
3677 if ((HelperFn = CGM.getAtomicSetterHelperFnMap(Ty)))
3678 return HelperFn;
3679
3680 ASTContext &C = getContext();
3681 IdentifierInfo *II
3682 = &CGM.getContext().Idents.get("__assign_helper_atomic_property_");
3683
3684 QualType ReturnTy = C.VoidTy;
3685 QualType DestTy = C.getPointerType(Ty);
3686 QualType SrcTy = Ty;
3687 SrcTy.addConst();
3688 SrcTy = C.getPointerType(SrcTy);
3689
3690 SmallVector<QualType, 2> ArgTys;
3691 ArgTys.push_back(DestTy);
3692 ArgTys.push_back(SrcTy);
3693 QualType FunctionTy = C.getFunctionType(ReturnTy, ArgTys, {});
3694
3695 FunctionDecl *FD = FunctionDecl::Create(
3696 C, C.getTranslationUnitDecl(), SourceLocation(), SourceLocation(), II,
3697 FunctionTy, nullptr, SC_Static, false, false, false);
3698
3699 FunctionArgList args;
3700 ParmVarDecl *Params[2];
3701 ParmVarDecl *DstDecl = ParmVarDecl::Create(
3702 C, FD, SourceLocation(), SourceLocation(), nullptr, DestTy,
3703 C.getTrivialTypeSourceInfo(DestTy, SourceLocation()), SC_None,
3704 /*DefArg=*/nullptr);
3705 args.push_back(Params[0] = DstDecl);
3706 ParmVarDecl *SrcDecl = ParmVarDecl::Create(
3707 C, FD, SourceLocation(), SourceLocation(), nullptr, SrcTy,
3708 C.getTrivialTypeSourceInfo(SrcTy, SourceLocation()), SC_None,
3709 /*DefArg=*/nullptr);
3710 args.push_back(Params[1] = SrcDecl);
3711 FD->setParams(Params);
3712
3713 const CGFunctionInfo &FI =
3714 CGM.getTypes().arrangeBuiltinFunctionDeclaration(ReturnTy, args);
3715
3716 llvm::FunctionType *LTy = CGM.getTypes().GetFunctionType(FI);
3717
3718 llvm::Function *Fn =
3719 llvm::Function::Create(LTy, llvm::GlobalValue::InternalLinkage,
3720 "__assign_helper_atomic_property_",
3721 &CGM.getModule());
3722
3723 CGM.SetInternalFunctionAttributes(GlobalDecl(), Fn, FI);
3724
3725 StartFunction(FD, ReturnTy, Fn, FI, args);
3726
3727 DeclRefExpr DstExpr(C, DstDecl, false, DestTy, VK_PRValue, SourceLocation());
3728 UnaryOperator *DST = UnaryOperator::Create(
3729 C, &DstExpr, UO_Deref, DestTy->getPointeeType(), VK_LValue, OK_Ordinary,
3730 SourceLocation(), false, FPOptionsOverride());
3731
3732 DeclRefExpr SrcExpr(C, SrcDecl, false, SrcTy, VK_PRValue, SourceLocation());
3733 UnaryOperator *SRC = UnaryOperator::Create(
3734 C, &SrcExpr, UO_Deref, SrcTy->getPointeeType(), VK_LValue, OK_Ordinary,
3735 SourceLocation(), false, FPOptionsOverride());
3736
3737 Expr *Args[2] = {DST, SRC};
3738 CallExpr *CalleeExp = cast<CallExpr>(PID->getSetterCXXAssignment());
3739 CXXOperatorCallExpr *TheCall = CXXOperatorCallExpr::Create(
3740 C, OO_Equal, CalleeExp->getCallee(), Args, DestTy->getPointeeType(),
3741 VK_LValue, SourceLocation(), FPOptionsOverride());
3742
3743 EmitStmt(TheCall);
3744
3745 FinishFunction();
3746 HelperFn = llvm::ConstantExpr::getBitCast(Fn, VoidPtrTy);
3747 CGM.setAtomicSetterHelperFnMap(Ty, HelperFn);
3748 return HelperFn;
3749}
3750
3751llvm::Constant *
3752CodeGenFunction::GenerateObjCAtomicGetterCopyHelperFunction(
3753 const ObjCPropertyImplDecl *PID) {
3754 if (!getLangOpts().CPlusPlus ||
3755 !getLangOpts().ObjCRuntime.hasAtomicCopyHelper())
3756 return nullptr;
3757 const ObjCPropertyDecl *PD = PID->getPropertyDecl();
3758 QualType Ty = PD->getType();
3759 if (!Ty->isRecordType())
3760 return nullptr;
3761 if ((!(PD->getPropertyAttributes() & ObjCPropertyAttribute::kind_atomic)))
3762 return nullptr;
3763 llvm::Constant *HelperFn = nullptr;
3764 if (hasTrivialGetExpr(PID))
3765 return nullptr;
3766 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", 3766, __extension__ __PRETTY_FUNCTION__
))
;
3767 if ((HelperFn = CGM.getAtomicGetterHelperFnMap(Ty)))
3768 return HelperFn;
3769
3770 ASTContext &C = getContext();
3771 IdentifierInfo *II =
3772 &CGM.getContext().Idents.get("__copy_helper_atomic_property_");
3773
3774 QualType ReturnTy = C.VoidTy;
3775 QualType DestTy = C.getPointerType(Ty);
3776 QualType SrcTy = Ty;
3777 SrcTy.addConst();
3778 SrcTy = C.getPointerType(SrcTy);
3779
3780 SmallVector<QualType, 2> ArgTys;
3781 ArgTys.push_back(DestTy);
3782 ArgTys.push_back(SrcTy);
3783 QualType FunctionTy = C.getFunctionType(ReturnTy, ArgTys, {});
3784
3785 FunctionDecl *FD = FunctionDecl::Create(
3786 C, C.getTranslationUnitDecl(), SourceLocation(), SourceLocation(), II,
3787 FunctionTy, nullptr, SC_Static, false, false, false);
3788
3789 FunctionArgList args;
3790 ParmVarDecl *Params[2];
3791 ParmVarDecl *DstDecl = ParmVarDecl::Create(
3792 C, FD, SourceLocation(), SourceLocation(), nullptr, DestTy,
3793 C.getTrivialTypeSourceInfo(DestTy, SourceLocation()), SC_None,
3794 /*DefArg=*/nullptr);
3795 args.push_back(Params[0] = DstDecl);
3796 ParmVarDecl *SrcDecl = ParmVarDecl::Create(
3797 C, FD, SourceLocation(), SourceLocation(), nullptr, SrcTy,
3798 C.getTrivialTypeSourceInfo(SrcTy, SourceLocation()), SC_None,
3799 /*DefArg=*/nullptr);
3800 args.push_back(Params[1] = SrcDecl);
3801 FD->setParams(Params);
3802
3803 const CGFunctionInfo &FI =
3804 CGM.getTypes().arrangeBuiltinFunctionDeclaration(ReturnTy, args);
3805
3806 llvm::FunctionType *LTy = CGM.getTypes().GetFunctionType(FI);
3807
3808 llvm::Function *Fn = llvm::Function::Create(
3809 LTy, llvm::GlobalValue::InternalLinkage, "__copy_helper_atomic_property_",
3810 &CGM.getModule());
3811
3812 CGM.SetInternalFunctionAttributes(GlobalDecl(), Fn, FI);
3813
3814 StartFunction(FD, ReturnTy, Fn, FI, args);
3815
3816 DeclRefExpr SrcExpr(getContext(), SrcDecl, false, SrcTy, VK_PRValue,
3817 SourceLocation());
3818
3819 UnaryOperator *SRC = UnaryOperator::Create(
3820 C, &SrcExpr, UO_Deref, SrcTy->getPointeeType(), VK_LValue, OK_Ordinary,
3821 SourceLocation(), false, FPOptionsOverride());
3822
3823 CXXConstructExpr *CXXConstExpr =
3824 cast<CXXConstructExpr>(PID->getGetterCXXConstructor());
3825
3826 SmallVector<Expr*, 4> ConstructorArgs;
3827 ConstructorArgs.push_back(SRC);
3828 ConstructorArgs.append(std::next(CXXConstExpr->arg_begin()),
3829 CXXConstExpr->arg_end());
3830
3831 CXXConstructExpr *TheCXXConstructExpr =
3832 CXXConstructExpr::Create(C, Ty, SourceLocation(),
3833 CXXConstExpr->getConstructor(),
3834 CXXConstExpr->isElidable(),
3835 ConstructorArgs,
3836 CXXConstExpr->hadMultipleCandidates(),
3837 CXXConstExpr->isListInitialization(),
3838 CXXConstExpr->isStdInitListInitialization(),
3839 CXXConstExpr->requiresZeroInitialization(),
3840 CXXConstExpr->getConstructionKind(),
3841 SourceRange());
3842
3843 DeclRefExpr DstExpr(getContext(), DstDecl, false, DestTy, VK_PRValue,
3844 SourceLocation());
3845
3846 RValue DV = EmitAnyExpr(&DstExpr);
3847 CharUnits Alignment =
3848 getContext().getTypeAlignInChars(TheCXXConstructExpr->getType());
3849 EmitAggExpr(TheCXXConstructExpr,
3850 AggValueSlot::forAddr(
3851 Address(DV.getScalarVal(), ConvertTypeForMem(Ty), Alignment),
3852 Qualifiers(), AggValueSlot::IsDestructed,
3853 AggValueSlot::DoesNotNeedGCBarriers,
3854 AggValueSlot::IsNotAliased, AggValueSlot::DoesNotOverlap));
3855
3856 FinishFunction();
3857 HelperFn = llvm::ConstantExpr::getBitCast(Fn, VoidPtrTy);
3858 CGM.setAtomicGetterHelperFnMap(Ty, HelperFn);
3859 return HelperFn;
3860}
3861
3862llvm::Value *
3863CodeGenFunction::EmitBlockCopyAndAutorelease(llvm::Value *Block, QualType Ty) {
3864 // Get selectors for retain/autorelease.
3865 IdentifierInfo *CopyID = &getContext().Idents.get("copy");
3866 Selector CopySelector =
3867 getContext().Selectors.getNullarySelector(CopyID);
3868 IdentifierInfo *AutoreleaseID = &getContext().Idents.get("autorelease");
3869 Selector AutoreleaseSelector =
3870 getContext().Selectors.getNullarySelector(AutoreleaseID);
3871
3872 // Emit calls to retain/autorelease.
3873 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
3874 llvm::Value *Val = Block;
3875 RValue Result;
3876 Result = Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
3877 Ty, CopySelector,
3878 Val, CallArgList(), nullptr, nullptr);
3879 Val = Result.getScalarVal();
3880 Result = Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
3881 Ty, AutoreleaseSelector,
3882 Val, CallArgList(), nullptr, nullptr);
3883 Val = Result.getScalarVal();
3884 return Val;
3885}
3886
3887static unsigned getBaseMachOPlatformID(const llvm::Triple &TT) {
3888 switch (TT.getOS()) {
3889 case llvm::Triple::Darwin:
3890 case llvm::Triple::MacOSX:
3891 return llvm::MachO::PLATFORM_MACOS;
3892 case llvm::Triple::IOS:
3893 return llvm::MachO::PLATFORM_IOS;
3894 case llvm::Triple::TvOS:
3895 return llvm::MachO::PLATFORM_TVOS;
3896 case llvm::Triple::WatchOS:
3897 return llvm::MachO::PLATFORM_WATCHOS;
3898 case llvm::Triple::DriverKit:
3899 return llvm::MachO::PLATFORM_DRIVERKIT;
3900 default:
3901 return /*Unknown platform*/ 0;
3902 }
3903}
3904
3905static llvm::Value *emitIsPlatformVersionAtLeast(CodeGenFunction &CGF,
3906 const VersionTuple &Version) {
3907 CodeGenModule &CGM = CGF.CGM;
3908 // Note: we intend to support multi-platform version checks, so reserve
3909 // the room for a dual platform checking invocation that will be
3910 // implemented in the future.
3911 llvm::SmallVector<llvm::Value *, 8> Args;
3912
3913 auto EmitArgs = [&](const VersionTuple &Version, const llvm::Triple &TT) {
3914 Optional<unsigned> Min = Version.getMinor(), SMin = Version.getSubminor();
3915 Args.push_back(
3916 llvm::ConstantInt::get(CGM.Int32Ty, getBaseMachOPlatformID(TT)));
3917 Args.push_back(llvm::ConstantInt::get(CGM.Int32Ty, Version.getMajor()));
3918 Args.push_back(llvm::ConstantInt::get(CGM.Int32Ty, Min.value_or(0)));
3919 Args.push_back(llvm::ConstantInt::get(CGM.Int32Ty, SMin.value_or(0)));
3920 };
3921
3922 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", 3922, __extension__ __PRETTY_FUNCTION__
))
;
3923 EmitArgs(Version, CGM.getTarget().getTriple());
3924
3925 if (!CGM.IsPlatformVersionAtLeastFn) {
3926 llvm::FunctionType *FTy = llvm::FunctionType::get(
3927 CGM.Int32Ty, {CGM.Int32Ty, CGM.Int32Ty, CGM.Int32Ty, CGM.Int32Ty},
3928 false);
3929 CGM.IsPlatformVersionAtLeastFn =
3930 CGM.CreateRuntimeFunction(FTy, "__isPlatformVersionAtLeast");
3931 }
3932
3933 llvm::Value *Check =
3934 CGF.EmitNounwindRuntimeCall(CGM.IsPlatformVersionAtLeastFn, Args);
3935 return CGF.Builder.CreateICmpNE(Check,
3936 llvm::Constant::getNullValue(CGM.Int32Ty));
3937}
3938
3939llvm::Value *
3940CodeGenFunction::EmitBuiltinAvailable(const VersionTuple &Version) {
3941 // Darwin uses the new __isPlatformVersionAtLeast family of routines.
3942 if (CGM.getTarget().getTriple().isOSDarwin())
3943 return emitIsPlatformVersionAtLeast(*this, Version);
3944
3945 if (!CGM.IsOSVersionAtLeastFn) {
3946 llvm::FunctionType *FTy =
3947 llvm::FunctionType::get(Int32Ty, {Int32Ty, Int32Ty, Int32Ty}, false);
3948 CGM.IsOSVersionAtLeastFn =
3949 CGM.CreateRuntimeFunction(FTy, "__isOSVersionAtLeast");
3950 }
3951
3952 Optional<unsigned> Min = Version.getMinor(), SMin = Version.getSubminor();
3953 llvm::Value *Args[] = {
3954 llvm::ConstantInt::get(CGM.Int32Ty, Version.getMajor()),
3955 llvm::ConstantInt::get(CGM.Int32Ty, Min.value_or(0)),
3956 llvm::ConstantInt::get(CGM.Int32Ty, SMin.value_or(0))};
3957
3958 llvm::Value *CallRes =
3959 EmitNounwindRuntimeCall(CGM.IsOSVersionAtLeastFn, Args);
3960
3961 return Builder.CreateICmpNE(CallRes, llvm::Constant::getNullValue(Int32Ty));
3962}
3963
3964static bool isFoundationNeededForDarwinAvailabilityCheck(
3965 const llvm::Triple &TT, const VersionTuple &TargetVersion) {
3966 VersionTuple FoundationDroppedInVersion;
3967 switch (TT.getOS()) {
3968 case llvm::Triple::IOS:
3969 case llvm::Triple::TvOS:
3970 FoundationDroppedInVersion = VersionTuple(/*Major=*/13);
3971 break;
3972 case llvm::Triple::WatchOS:
3973 FoundationDroppedInVersion = VersionTuple(/*Major=*/6);
3974 break;
3975 case llvm::Triple::Darwin:
3976 case llvm::Triple::MacOSX:
3977 FoundationDroppedInVersion = VersionTuple(/*Major=*/10, /*Minor=*/15);
3978 break;
3979 case llvm::Triple::DriverKit:
3980 // DriverKit doesn't need Foundation.
3981 return false;
3982 default:
3983 llvm_unreachable("Unexpected OS")::llvm::llvm_unreachable_internal("Unexpected OS", "clang/lib/CodeGen/CGObjC.cpp"
, 3983)
;
3984 }
3985 return TargetVersion < FoundationDroppedInVersion;
3986}
3987
3988void CodeGenModule::emitAtAvailableLinkGuard() {
3989 if (!IsPlatformVersionAtLeastFn)
3990 return;
3991 // @available requires CoreFoundation only on Darwin.
3992 if (!Target.getTriple().isOSDarwin())
3993 return;
3994 // @available doesn't need Foundation on macOS 10.15+, iOS/tvOS 13+, or
3995 // watchOS 6+.
3996 if (!isFoundationNeededForDarwinAvailabilityCheck(
3997 Target.getTriple(), Target.getPlatformMinVersion()))
3998 return;
3999 // Add -framework CoreFoundation to the linker commands. We still want to
4000 // emit the core foundation reference down below because otherwise if
4001 // CoreFoundation is not used in the code, the linker won't link the
4002 // framework.
4003 auto &Context = getLLVMContext();
4004 llvm::Metadata *Args[2] = {llvm::MDString::get(Context, "-framework"),
4005 llvm::MDString::get(Context, "CoreFoundation")};
4006 LinkerOptionsMetadata.push_back(llvm::MDNode::get(Context, Args));
4007 // Emit a reference to a symbol from CoreFoundation to ensure that
4008 // CoreFoundation is linked into the final binary.
4009 llvm::FunctionType *FTy =
4010 llvm::FunctionType::get(Int32Ty, {VoidPtrTy}, false);
4011 llvm::FunctionCallee CFFunc =
4012 CreateRuntimeFunction(FTy, "CFBundleGetVersionNumber");
4013
4014 llvm::FunctionType *CheckFTy = llvm::FunctionType::get(VoidTy, {}, false);
4015 llvm::FunctionCallee CFLinkCheckFuncRef = CreateRuntimeFunction(
4016 CheckFTy, "__clang_at_available_requires_core_foundation_framework",
4017 llvm::AttributeList(), /*Local=*/true);
4018 llvm::Function *CFLinkCheckFunc =
4019 cast<llvm::Function>(CFLinkCheckFuncRef.getCallee()->stripPointerCasts());
4020 if (CFLinkCheckFunc->empty()) {
4021 CFLinkCheckFunc->setLinkage(llvm::GlobalValue::LinkOnceAnyLinkage);
4022 CFLinkCheckFunc->setVisibility(llvm::GlobalValue::HiddenVisibility);
4023 CodeGenFunction CGF(*this);
4024 CGF.Builder.SetInsertPoint(CGF.createBasicBlock("", CFLinkCheckFunc));
4025 CGF.EmitNounwindRuntimeCall(CFFunc,
4026 llvm::Constant::getNullValue(VoidPtrTy));
4027 CGF.Builder.CreateUnreachable();
4028 addCompilerUsedGlobal(CFLinkCheckFunc);
4029 }
4030}
4031
4032CGObjCRuntime::~CGObjCRuntime() {}