Bug Summary

File:clang/lib/CodeGen/CGObjC.cpp
Warning:line 3155, 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 -disable-llvm-verifier -discard-value-names -main-file-name CGObjC.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -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 -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/tools/clang/lib/CodeGen -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -D CLANG_ROUND_TRIP_CC1_ARGS=ON -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/tools/clang/lib/CodeGen -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/include -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/include -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include -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-14/lib/clang/14.0.0/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 -O2 -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 -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/tools/clang/lib/CodeGen -fdebug-prefix-map=/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -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-2021-08-28-193554-24367-1 -x c++ /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/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\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/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 Address BitCast = Builder.CreateBitCast(Temporary, ConvertType(ArgQT));
96 Args.add(RValue::get(BitCast.getPointer()), ArgQT);
97
98 // Create char array to store type encoding
99 std::string Str;
100 getContext().getObjCEncodingForType(ValueType, Str);
101 llvm::Constant *GV = CGM.GetAddrOfConstantCString(Str).getPointer();
102
103 // Cast type encoding to correct type
104 const ParmVarDecl *EncodingDecl = BoxingMethod->parameters()[1];
105 QualType EncodingQT = EncodingDecl->getType().getUnqualifiedType();
106 llvm::Value *Cast = Builder.CreateBitCast(GV, ConvertType(EncodingQT));
107
108 Args.add(RValue::get(Cast), EncodingQT);
109 } else {
110 Args.add(EmitAnyExpr(SubExpr), ArgQT);
111 }
112
113 RValue result = Runtime.GenerateMessageSend(
114 *this, ReturnValueSlot(), BoxingMethod->getReturnType(), Sel, Receiver,
115 Args, ClassDecl, BoxingMethod);
116 return Builder.CreateBitCast(result.getScalarVal(),
117 ConvertType(E->getType()));
118}
119
120llvm::Value *CodeGenFunction::EmitObjCCollectionLiteral(const Expr *E,
121 const ObjCMethodDecl *MethodWithObjects) {
122 ASTContext &Context = CGM.getContext();
123 const ObjCDictionaryLiteral *DLE = nullptr;
124 const ObjCArrayLiteral *ALE = dyn_cast<ObjCArrayLiteral>(E);
125 if (!ALE)
126 DLE = cast<ObjCDictionaryLiteral>(E);
127
128 // Optimize empty collections by referencing constants, when available.
129 uint64_t NumElements =
130 ALE ? ALE->getNumElements() : DLE->getNumElements();
131 if (NumElements == 0 && CGM.getLangOpts().ObjCRuntime.hasEmptyCollections()) {
132 StringRef ConstantName = ALE ? "__NSArray0__" : "__NSDictionary0__";
133 QualType IdTy(CGM.getContext().getObjCIdType());
134 llvm::Constant *Constant =
135 CGM.CreateRuntimeVariable(ConvertType(IdTy), ConstantName);
136 LValue LV = MakeNaturalAlignAddrLValue(Constant, IdTy);
137 llvm::Value *Ptr = EmitLoadOfScalar(LV, E->getBeginLoc());
138 cast<llvm::LoadInst>(Ptr)->setMetadata(
139 CGM.getModule().getMDKindID("invariant.load"),
140 llvm::MDNode::get(getLLVMContext(), None));
141 return Builder.CreateBitCast(Ptr, ConvertType(E->getType()));
142 }
143
144 // Compute the type of the array we're initializing.
145 llvm::APInt APNumElements(Context.getTypeSize(Context.getSizeType()),
146 NumElements);
147 QualType ElementType = Context.getObjCIdType().withConst();
148 QualType ElementArrayType
149 = Context.getConstantArrayType(ElementType, APNumElements, nullptr,
150 ArrayType::Normal, /*IndexTypeQuals=*/0);
151
152 // Allocate the temporary array(s).
153 Address Objects = CreateMemTemp(ElementArrayType, "objects");
154 Address Keys = Address::invalid();
155 if (DLE)
156 Keys = CreateMemTemp(ElementArrayType, "keys");
157
158 // In ARC, we may need to do extra work to keep all the keys and
159 // values alive until after the call.
160 SmallVector<llvm::Value *, 16> NeededObjects;
161 bool TrackNeededObjects =
162 (getLangOpts().ObjCAutoRefCount &&
163 CGM.getCodeGenOpts().OptimizationLevel != 0);
164
165 // Perform the actual initialialization of the array(s).
166 for (uint64_t i = 0; i < NumElements; i++) {
167 if (ALE) {
168 // Emit the element and store it to the appropriate array slot.
169 const Expr *Rhs = ALE->getElement(i);
170 LValue LV = MakeAddrLValue(Builder.CreateConstArrayGEP(Objects, i),
171 ElementType, AlignmentSource::Decl);
172
173 llvm::Value *value = EmitScalarExpr(Rhs);
174 EmitStoreThroughLValue(RValue::get(value), LV, true);
175 if (TrackNeededObjects) {
176 NeededObjects.push_back(value);
177 }
178 } else {
179 // Emit the key and store it to the appropriate array slot.
180 const Expr *Key = DLE->getKeyValueElement(i).Key;
181 LValue KeyLV = MakeAddrLValue(Builder.CreateConstArrayGEP(Keys, i),
182 ElementType, AlignmentSource::Decl);
183 llvm::Value *keyValue = EmitScalarExpr(Key);
184 EmitStoreThroughLValue(RValue::get(keyValue), KeyLV, /*isInit=*/true);
185
186 // Emit the value and store it to the appropriate array slot.
187 const Expr *Value = DLE->getKeyValueElement(i).Value;
188 LValue ValueLV = MakeAddrLValue(Builder.CreateConstArrayGEP(Objects, i),
189 ElementType, AlignmentSource::Decl);
190 llvm::Value *valueValue = EmitScalarExpr(Value);
191 EmitStoreThroughLValue(RValue::get(valueValue), ValueLV, /*isInit=*/true);
192 if (TrackNeededObjects) {
193 NeededObjects.push_back(keyValue);
194 NeededObjects.push_back(valueValue);
195 }
196 }
197 }
198
199 // Generate the argument list.
200 CallArgList Args;
201 ObjCMethodDecl::param_const_iterator PI = MethodWithObjects->param_begin();
202 const ParmVarDecl *argDecl = *PI++;
203 QualType ArgQT = argDecl->getType().getUnqualifiedType();
204 Args.add(RValue::get(Objects.getPointer()), ArgQT);
205 if (DLE) {
206 argDecl = *PI++;
207 ArgQT = argDecl->getType().getUnqualifiedType();
208 Args.add(RValue::get(Keys.getPointer()), ArgQT);
209 }
210 argDecl = *PI;
211 ArgQT = argDecl->getType().getUnqualifiedType();
212 llvm::Value *Count =
213 llvm::ConstantInt::get(CGM.getTypes().ConvertType(ArgQT), NumElements);
214 Args.add(RValue::get(Count), ArgQT);
215
216 // Generate a reference to the class pointer, which will be the receiver.
217 Selector Sel = MethodWithObjects->getSelector();
218 QualType ResultType = E->getType();
219 const ObjCObjectPointerType *InterfacePointerType
220 = ResultType->getAsObjCInterfacePointerType();
221 ObjCInterfaceDecl *Class
222 = InterfacePointerType->getObjectType()->getInterface();
223 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
224 llvm::Value *Receiver = Runtime.GetClass(*this, Class);
225
226 // Generate the message send.
227 RValue result = Runtime.GenerateMessageSend(
228 *this, ReturnValueSlot(), MethodWithObjects->getReturnType(), Sel,
229 Receiver, Args, Class, MethodWithObjects);
230
231 // The above message send needs these objects, but in ARC they are
232 // passed in a buffer that is essentially __unsafe_unretained.
233 // Therefore we must prevent the optimizer from releasing them until
234 // after the call.
235 if (TrackNeededObjects) {
236 EmitARCIntrinsicUse(NeededObjects);
237 }
238
239 return Builder.CreateBitCast(result.getScalarVal(),
240 ConvertType(E->getType()));
241}
242
243llvm::Value *CodeGenFunction::EmitObjCArrayLiteral(const ObjCArrayLiteral *E) {
244 return EmitObjCCollectionLiteral(E, E->getArrayWithObjectsMethod());
245}
246
247llvm::Value *CodeGenFunction::EmitObjCDictionaryLiteral(
248 const ObjCDictionaryLiteral *E) {
249 return EmitObjCCollectionLiteral(E, E->getDictWithObjectsMethod());
250}
251
252/// Emit a selector.
253llvm::Value *CodeGenFunction::EmitObjCSelectorExpr(const ObjCSelectorExpr *E) {
254 // Untyped selector.
255 // Note that this implementation allows for non-constant strings to be passed
256 // as arguments to @selector(). Currently, the only thing preventing this
257 // behaviour is the type checking in the front end.
258 return CGM.getObjCRuntime().GetSelector(*this, E->getSelector());
259}
260
261llvm::Value *CodeGenFunction::EmitObjCProtocolExpr(const ObjCProtocolExpr *E) {
262 // FIXME: This should pass the Decl not the name.
263 return CGM.getObjCRuntime().GenerateProtocolRef(*this, E->getProtocol());
264}
265
266/// Adjust the type of an Objective-C object that doesn't match up due
267/// to type erasure at various points, e.g., related result types or the use
268/// of parameterized classes.
269static RValue AdjustObjCObjectType(CodeGenFunction &CGF, QualType ExpT,
270 RValue Result) {
271 if (!ExpT->isObjCRetainableType())
272 return Result;
273
274 // If the converted types are the same, we're done.
275 llvm::Type *ExpLLVMTy = CGF.ConvertType(ExpT);
276 if (ExpLLVMTy == Result.getScalarVal()->getType())
277 return Result;
278
279 // We have applied a substitution. Cast the rvalue appropriately.
280 return RValue::get(CGF.Builder.CreateBitCast(Result.getScalarVal(),
281 ExpLLVMTy));
282}
283
284/// Decide whether to extend the lifetime of the receiver of a
285/// returns-inner-pointer message.
286static bool
287shouldExtendReceiverForInnerPointerMessage(const ObjCMessageExpr *message) {
288 switch (message->getReceiverKind()) {
289
290 // For a normal instance message, we should extend unless the
291 // receiver is loaded from a variable with precise lifetime.
292 case ObjCMessageExpr::Instance: {
293 const Expr *receiver = message->getInstanceReceiver();
294
295 // Look through OVEs.
296 if (auto opaque = dyn_cast<OpaqueValueExpr>(receiver)) {
297 if (opaque->getSourceExpr())
298 receiver = opaque->getSourceExpr()->IgnoreParens();
299 }
300
301 const ImplicitCastExpr *ice = dyn_cast<ImplicitCastExpr>(receiver);
302 if (!ice || ice->getCastKind() != CK_LValueToRValue) return true;
303 receiver = ice->getSubExpr()->IgnoreParens();
304
305 // Look through OVEs.
306 if (auto opaque = dyn_cast<OpaqueValueExpr>(receiver)) {
307 if (opaque->getSourceExpr())
308 receiver = opaque->getSourceExpr()->IgnoreParens();
309 }
310
311 // Only __strong variables.
312 if (receiver->getType().getObjCLifetime() != Qualifiers::OCL_Strong)
313 return true;
314
315 // All ivars and fields have precise lifetime.
316 if (isa<MemberExpr>(receiver) || isa<ObjCIvarRefExpr>(receiver))
317 return false;
318
319 // Otherwise, check for variables.
320 const DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(ice->getSubExpr());
321 if (!declRef) return true;
322 const VarDecl *var = dyn_cast<VarDecl>(declRef->getDecl());
323 if (!var) return true;
324
325 // All variables have precise lifetime except local variables with
326 // automatic storage duration that aren't specially marked.
327 return (var->hasLocalStorage() &&
328 !var->hasAttr<ObjCPreciseLifetimeAttr>());
329 }
330
331 case ObjCMessageExpr::Class:
332 case ObjCMessageExpr::SuperClass:
333 // It's never necessary for class objects.
334 return false;
335
336 case ObjCMessageExpr::SuperInstance:
337 // We generally assume that 'self' lives throughout a method call.
338 return false;
339 }
340
341 llvm_unreachable("invalid receiver kind")::llvm::llvm_unreachable_internal("invalid receiver kind", "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 341)
;
342}
343
344/// Given an expression of ObjC pointer type, check whether it was
345/// immediately loaded from an ARC __weak l-value.
346static const Expr *findWeakLValue(const Expr *E) {
347 assert(E->getType()->isObjCRetainableType())(static_cast <bool> (E->getType()->isObjCRetainableType
()) ? void (0) : __assert_fail ("E->getType()->isObjCRetainableType()"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 347, __extension__ __PRETTY_FUNCTION__))
;
348 E = E->IgnoreParens();
349 if (auto CE = dyn_cast<CastExpr>(E)) {
350 if (CE->getCastKind() == CK_LValueToRValue) {
351 if (CE->getSubExpr()->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
352 return CE->getSubExpr();
353 }
354 }
355
356 return nullptr;
357}
358
359/// The ObjC runtime may provide entrypoints that are likely to be faster
360/// than an ordinary message send of the appropriate selector.
361///
362/// The entrypoints are guaranteed to be equivalent to just sending the
363/// corresponding message. If the entrypoint is implemented naively as just a
364/// message send, using it is a trade-off: it sacrifices a few cycles of
365/// overhead to save a small amount of code. However, it's possible for
366/// runtimes to detect and special-case classes that use "standard"
367/// behavior; if that's dynamically a large proportion of all objects, using
368/// the entrypoint will also be faster than using a message send.
369///
370/// If the runtime does support a required entrypoint, then this method will
371/// generate a call and return the resulting value. Otherwise it will return
372/// None and the caller can generate a msgSend instead.
373static Optional<llvm::Value *>
374tryGenerateSpecializedMessageSend(CodeGenFunction &CGF, QualType ResultType,
375 llvm::Value *Receiver,
376 const CallArgList& Args, Selector Sel,
377 const ObjCMethodDecl *method,
378 bool isClassMessage) {
379 auto &CGM = CGF.CGM;
380 if (!CGM.getCodeGenOpts().ObjCConvertMessagesToRuntimeCalls)
381 return None;
382
383 auto &Runtime = CGM.getLangOpts().ObjCRuntime;
384 switch (Sel.getMethodFamily()) {
385 case OMF_alloc:
386 if (isClassMessage &&
387 Runtime.shouldUseRuntimeFunctionsForAlloc() &&
388 ResultType->isObjCObjectPointerType()) {
389 // [Foo alloc] -> objc_alloc(Foo) or
390 // [self alloc] -> objc_alloc(self)
391 if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "alloc")
392 return CGF.EmitObjCAlloc(Receiver, CGF.ConvertType(ResultType));
393 // [Foo allocWithZone:nil] -> objc_allocWithZone(Foo) or
394 // [self allocWithZone:nil] -> objc_allocWithZone(self)
395 if (Sel.isKeywordSelector() && Sel.getNumArgs() == 1 &&
396 Args.size() == 1 && Args.front().getType()->isPointerType() &&
397 Sel.getNameForSlot(0) == "allocWithZone") {
398 const llvm::Value* arg = Args.front().getKnownRValue().getScalarVal();
399 if (isa<llvm::ConstantPointerNull>(arg))
400 return CGF.EmitObjCAllocWithZone(Receiver,
401 CGF.ConvertType(ResultType));
402 return None;
403 }
404 }
405 break;
406
407 case OMF_autorelease:
408 if (ResultType->isObjCObjectPointerType() &&
409 CGM.getLangOpts().getGC() == LangOptions::NonGC &&
410 Runtime.shouldUseARCFunctionsForRetainRelease())
411 return CGF.EmitObjCAutorelease(Receiver, CGF.ConvertType(ResultType));
412 break;
413
414 case OMF_retain:
415 if (ResultType->isObjCObjectPointerType() &&
416 CGM.getLangOpts().getGC() == LangOptions::NonGC &&
417 Runtime.shouldUseARCFunctionsForRetainRelease())
418 return CGF.EmitObjCRetainNonBlock(Receiver, CGF.ConvertType(ResultType));
419 break;
420
421 case OMF_release:
422 if (ResultType->isVoidType() &&
423 CGM.getLangOpts().getGC() == LangOptions::NonGC &&
424 Runtime.shouldUseARCFunctionsForRetainRelease()) {
425 CGF.EmitObjCRelease(Receiver, ARCPreciseLifetime);
426 return nullptr;
427 }
428 break;
429
430 default:
431 break;
432 }
433 return None;
434}
435
436CodeGen::RValue CGObjCRuntime::GeneratePossiblySpecializedMessageSend(
437 CodeGenFunction &CGF, ReturnValueSlot Return, QualType ResultType,
438 Selector Sel, llvm::Value *Receiver, const CallArgList &Args,
439 const ObjCInterfaceDecl *OID, const ObjCMethodDecl *Method,
440 bool isClassMessage) {
441 if (Optional<llvm::Value *> SpecializedResult =
442 tryGenerateSpecializedMessageSend(CGF, ResultType, Receiver, Args,
443 Sel, Method, isClassMessage)) {
444 return RValue::get(SpecializedResult.getValue());
445 }
446 return GenerateMessageSend(CGF, Return, ResultType, Sel, Receiver, Args, OID,
447 Method);
448}
449
450static void AppendFirstImpliedRuntimeProtocols(
451 const ObjCProtocolDecl *PD,
452 llvm::UniqueVector<const ObjCProtocolDecl *> &PDs) {
453 if (!PD->isNonRuntimeProtocol()) {
454 const auto *Can = PD->getCanonicalDecl();
455 PDs.insert(Can);
456 return;
457 }
458
459 for (const auto *ParentPD : PD->protocols())
460 AppendFirstImpliedRuntimeProtocols(ParentPD, PDs);
461}
462
463std::vector<const ObjCProtocolDecl *>
464CGObjCRuntime::GetRuntimeProtocolList(ObjCProtocolDecl::protocol_iterator begin,
465 ObjCProtocolDecl::protocol_iterator end) {
466 std::vector<const ObjCProtocolDecl *> RuntimePds;
467 llvm::DenseSet<const ObjCProtocolDecl *> NonRuntimePDs;
468
469 for (; begin != end; ++begin) {
470 const auto *It = *begin;
471 const auto *Can = It->getCanonicalDecl();
472 if (Can->isNonRuntimeProtocol())
473 NonRuntimePDs.insert(Can);
474 else
475 RuntimePds.push_back(Can);
476 }
477
478 // If there are no non-runtime protocols then we can just stop now.
479 if (NonRuntimePDs.empty())
480 return RuntimePds;
481
482 // Else we have to search through the non-runtime protocol's inheritancy
483 // hierarchy DAG stopping whenever a branch either finds a runtime protocol or
484 // a non-runtime protocol without any parents. These are the "first-implied"
485 // protocols from a non-runtime protocol.
486 llvm::UniqueVector<const ObjCProtocolDecl *> FirstImpliedProtos;
487 for (const auto *PD : NonRuntimePDs)
488 AppendFirstImpliedRuntimeProtocols(PD, FirstImpliedProtos);
489
490 // Walk the Runtime list to get all protocols implied via the inclusion of
491 // this protocol, e.g. all protocols it inherits from including itself.
492 llvm::DenseSet<const ObjCProtocolDecl *> AllImpliedProtocols;
493 for (const auto *PD : RuntimePds) {
494 const auto *Can = PD->getCanonicalDecl();
495 AllImpliedProtocols.insert(Can);
496 Can->getImpliedProtocols(AllImpliedProtocols);
497 }
498
499 // Similar to above, walk the list of first-implied protocols to find the set
500 // all the protocols implied excluding the listed protocols themselves since
501 // they are not yet a part of the `RuntimePds` list.
502 for (const auto *PD : FirstImpliedProtos) {
503 PD->getImpliedProtocols(AllImpliedProtocols);
504 }
505
506 // From the first-implied list we have to finish building the final protocol
507 // list. If a protocol in the first-implied list was already implied via some
508 // inheritance path through some other protocols then it would be redundant to
509 // add it here and so we skip over it.
510 for (const auto *PD : FirstImpliedProtos) {
511 if (!AllImpliedProtocols.contains(PD)) {
512 RuntimePds.push_back(PD);
513 }
514 }
515
516 return RuntimePds;
517}
518
519/// Instead of '[[MyClass alloc] init]', try to generate
520/// 'objc_alloc_init(MyClass)'. This provides a code size improvement on the
521/// caller side, as well as the optimized objc_alloc.
522static Optional<llvm::Value *>
523tryEmitSpecializedAllocInit(CodeGenFunction &CGF, const ObjCMessageExpr *OME) {
524 auto &Runtime = CGF.getLangOpts().ObjCRuntime;
525 if (!Runtime.shouldUseRuntimeFunctionForCombinedAllocInit())
526 return None;
527
528 // Match the exact pattern '[[MyClass alloc] init]'.
529 Selector Sel = OME->getSelector();
530 if (OME->getReceiverKind() != ObjCMessageExpr::Instance ||
531 !OME->getType()->isObjCObjectPointerType() || !Sel.isUnarySelector() ||
532 Sel.getNameForSlot(0) != "init")
533 return None;
534
535 // Okay, this is '[receiver init]', check if 'receiver' is '[cls alloc]'
536 // with 'cls' a Class.
537 auto *SubOME =
538 dyn_cast<ObjCMessageExpr>(OME->getInstanceReceiver()->IgnoreParenCasts());
539 if (!SubOME)
540 return None;
541 Selector SubSel = SubOME->getSelector();
542
543 if (!SubOME->getType()->isObjCObjectPointerType() ||
544 !SubSel.isUnarySelector() || SubSel.getNameForSlot(0) != "alloc")
545 return None;
546
547 llvm::Value *Receiver = nullptr;
548 switch (SubOME->getReceiverKind()) {
549 case ObjCMessageExpr::Instance:
550 if (!SubOME->getInstanceReceiver()->getType()->isObjCClassType())
551 return None;
552 Receiver = CGF.EmitScalarExpr(SubOME->getInstanceReceiver());
553 break;
554
555 case ObjCMessageExpr::Class: {
556 QualType ReceiverType = SubOME->getClassReceiver();
557 const ObjCObjectType *ObjTy = ReceiverType->castAs<ObjCObjectType>();
558 const ObjCInterfaceDecl *ID = ObjTy->getInterface();
559 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\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 559, __extension__ __PRETTY_FUNCTION__))
;
560 Receiver = CGF.CGM.getObjCRuntime().GetClass(CGF, ID);
561 break;
562 }
563 case ObjCMessageExpr::SuperInstance:
564 case ObjCMessageExpr::SuperClass:
565 return None;
566 }
567
568 return CGF.EmitObjCAllocInit(Receiver, CGF.ConvertType(OME->getType()));
569}
570
571RValue CodeGenFunction::EmitObjCMessageExpr(const ObjCMessageExpr *E,
572 ReturnValueSlot Return) {
573 // Only the lookup mechanism and first two arguments of the method
574 // implementation vary between runtimes. We can get the receiver and
575 // arguments in generic code.
576
577 bool isDelegateInit = E->isDelegateInitCall();
578
579 const ObjCMethodDecl *method = E->getMethodDecl();
580
581 // If the method is -retain, and the receiver's being loaded from
582 // a __weak variable, peephole the entire operation to objc_loadWeakRetained.
583 if (method && E->getReceiverKind() == ObjCMessageExpr::Instance &&
584 method->getMethodFamily() == OMF_retain) {
585 if (auto lvalueExpr = findWeakLValue(E->getInstanceReceiver())) {
586 LValue lvalue = EmitLValue(lvalueExpr);
587 llvm::Value *result = EmitARCLoadWeakRetained(lvalue.getAddress(*this));
588 return AdjustObjCObjectType(*this, E->getType(), RValue::get(result));
589 }
590 }
591
592 if (Optional<llvm::Value *> Val = tryEmitSpecializedAllocInit(*this, E))
593 return AdjustObjCObjectType(*this, E->getType(), RValue::get(*Val));
594
595 // We don't retain the receiver in delegate init calls, and this is
596 // safe because the receiver value is always loaded from 'self',
597 // which we zero out. We don't want to Block_copy block receivers,
598 // though.
599 bool retainSelf =
600 (!isDelegateInit &&
601 CGM.getLangOpts().ObjCAutoRefCount &&
602 method &&
603 method->hasAttr<NSConsumesSelfAttr>());
604
605 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
606 bool isSuperMessage = false;
607 bool isClassMessage = false;
608 ObjCInterfaceDecl *OID = nullptr;
609 // Find the receiver
610 QualType ReceiverType;
611 llvm::Value *Receiver = nullptr;
612 switch (E->getReceiverKind()) {
613 case ObjCMessageExpr::Instance:
614 ReceiverType = E->getInstanceReceiver()->getType();
615 isClassMessage = ReceiverType->isObjCClassType();
616 if (retainSelf) {
617 TryEmitResult ter = tryEmitARCRetainScalarExpr(*this,
618 E->getInstanceReceiver());
619 Receiver = ter.getPointer();
620 if (ter.getInt()) retainSelf = false;
621 } else
622 Receiver = EmitScalarExpr(E->getInstanceReceiver());
623 break;
624
625 case ObjCMessageExpr::Class: {
626 ReceiverType = E->getClassReceiver();
627 OID = ReceiverType->castAs<ObjCObjectType>()->getInterface();
628 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\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 628, __extension__ __PRETTY_FUNCTION__))
;
629 Receiver = Runtime.GetClass(*this, OID);
630 isClassMessage = true;
631 break;
632 }
633
634 case ObjCMessageExpr::SuperInstance:
635 ReceiverType = E->getSuperType();
636 Receiver = LoadObjCSelf();
637 isSuperMessage = true;
638 break;
639
640 case ObjCMessageExpr::SuperClass:
641 ReceiverType = E->getSuperType();
642 Receiver = LoadObjCSelf();
643 isSuperMessage = true;
644 isClassMessage = true;
645 break;
646 }
647
648 if (retainSelf)
649 Receiver = EmitARCRetainNonBlock(Receiver);
650
651 // In ARC, we sometimes want to "extend the lifetime"
652 // (i.e. retain+autorelease) of receivers of returns-inner-pointer
653 // messages.
654 if (getLangOpts().ObjCAutoRefCount && method &&
655 method->hasAttr<ObjCReturnsInnerPointerAttr>() &&
656 shouldExtendReceiverForInnerPointerMessage(E))
657 Receiver = EmitARCRetainAutorelease(ReceiverType, Receiver);
658
659 QualType ResultType = method ? method->getReturnType() : E->getType();
660
661 CallArgList Args;
662 EmitCallArgs(Args, method, E->arguments(), /*AC*/AbstractCallee(method));
663
664 // For delegate init calls in ARC, do an unsafe store of null into
665 // self. This represents the call taking direct ownership of that
666 // value. We have to do this after emitting the other call
667 // arguments because they might also reference self, but we don't
668 // have to worry about any of them modifying self because that would
669 // be an undefined read and write of an object in unordered
670 // expressions.
671 if (isDelegateInit) {
672 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\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 673, __extension__ __PRETTY_FUNCTION__))
673 "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\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 673, __extension__ __PRETTY_FUNCTION__))
;
674
675 // Do an unsafe store of null into self.
676 Address selfAddr =
677 GetAddrOfLocalVar(cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl());
678 Builder.CreateStore(getNullForVariable(selfAddr), selfAddr);
679 }
680
681 RValue result;
682 if (isSuperMessage) {
683 // super is only valid in an Objective-C method
684 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
685 bool isCategoryImpl = isa<ObjCCategoryImplDecl>(OMD->getDeclContext());
686 result = Runtime.GenerateMessageSendSuper(*this, Return, ResultType,
687 E->getSelector(),
688 OMD->getClassInterface(),
689 isCategoryImpl,
690 Receiver,
691 isClassMessage,
692 Args,
693 method);
694 } else {
695 // Call runtime methods directly if we can.
696 result = Runtime.GeneratePossiblySpecializedMessageSend(
697 *this, Return, ResultType, E->getSelector(), Receiver, Args, OID,
698 method, isClassMessage);
699 }
700
701 // For delegate init calls in ARC, implicitly store the result of
702 // the call back into self. This takes ownership of the value.
703 if (isDelegateInit) {
704 Address selfAddr =
705 GetAddrOfLocalVar(cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl());
706 llvm::Value *newSelf = result.getScalarVal();
707
708 // The delegate return type isn't necessarily a matching type; in
709 // fact, it's quite likely to be 'id'.
710 llvm::Type *selfTy = selfAddr.getElementType();
711 newSelf = Builder.CreateBitCast(newSelf, selfTy);
712
713 Builder.CreateStore(newSelf, selfAddr);
714 }
715
716 return AdjustObjCObjectType(*this, E->getType(), result);
717}
718
719namespace {
720struct FinishARCDealloc final : EHScopeStack::Cleanup {
721 void Emit(CodeGenFunction &CGF, Flags flags) override {
722 const ObjCMethodDecl *method = cast<ObjCMethodDecl>(CGF.CurCodeDecl);
723
724 const ObjCImplDecl *impl = cast<ObjCImplDecl>(method->getDeclContext());
725 const ObjCInterfaceDecl *iface = impl->getClassInterface();
726 if (!iface->getSuperClass()) return;
727
728 bool isCategory = isa<ObjCCategoryImplDecl>(impl);
729
730 // Call [super dealloc] if we have a superclass.
731 llvm::Value *self = CGF.LoadObjCSelf();
732
733 CallArgList args;
734 CGF.CGM.getObjCRuntime().GenerateMessageSendSuper(CGF, ReturnValueSlot(),
735 CGF.getContext().VoidTy,
736 method->getSelector(),
737 iface,
738 isCategory,
739 self,
740 /*is class msg*/ false,
741 args,
742 method);
743 }
744};
745}
746
747/// StartObjCMethod - Begin emission of an ObjCMethod. This generates
748/// the LLVM function and sets the other context used by
749/// CodeGenFunction.
750void CodeGenFunction::StartObjCMethod(const ObjCMethodDecl *OMD,
751 const ObjCContainerDecl *CD) {
752 SourceLocation StartLoc = OMD->getBeginLoc();
753 FunctionArgList args;
754 // Check if we should generate debug info for this method.
755 if (OMD->hasAttr<NoDebugAttr>())
756 DebugInfo = nullptr; // disable debug info indefinitely for this function
757
758 llvm::Function *Fn = CGM.getObjCRuntime().GenerateMethod(OMD, CD);
759
760 const CGFunctionInfo &FI = CGM.getTypes().arrangeObjCMethodDeclaration(OMD);
761 if (OMD->isDirectMethod()) {
762 Fn->setVisibility(llvm::Function::HiddenVisibility);
763 CGM.SetLLVMFunctionAttributes(OMD, FI, Fn, /*IsThunk=*/false);
764 CGM.SetLLVMFunctionAttributesForDefinition(OMD, Fn);
765 } else {
766 CGM.SetInternalFunctionAttributes(OMD, Fn, FI);
767 }
768
769 args.push_back(OMD->getSelfDecl());
770 args.push_back(OMD->getCmdDecl());
771
772 args.append(OMD->param_begin(), OMD->param_end());
773
774 CurGD = OMD;
775 CurEHLocation = OMD->getEndLoc();
776
777 StartFunction(OMD, OMD->getReturnType(), Fn, FI, args,
778 OMD->getLocation(), StartLoc);
779
780 if (OMD->isDirectMethod()) {
781 // This function is a direct call, it has to implement a nil check
782 // on entry.
783 //
784 // TODO: possibly have several entry points to elide the check
785 CGM.getObjCRuntime().GenerateDirectMethodPrologue(*this, Fn, OMD, CD);
786 }
787
788 // In ARC, certain methods get an extra cleanup.
789 if (CGM.getLangOpts().ObjCAutoRefCount &&
790 OMD->isInstanceMethod() &&
791 OMD->getSelector().isUnarySelector()) {
792 const IdentifierInfo *ident =
793 OMD->getSelector().getIdentifierInfoForSlot(0);
794 if (ident->isStr("dealloc"))
795 EHStack.pushCleanup<FinishARCDealloc>(getARCCleanupKind());
796 }
797}
798
799static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF,
800 LValue lvalue, QualType type);
801
802/// Generate an Objective-C method. An Objective-C method is a C function with
803/// its pointer, name, and types registered in the class structure.
804void CodeGenFunction::GenerateObjCMethod(const ObjCMethodDecl *OMD) {
805 StartObjCMethod(OMD, OMD->getClassInterface());
806 PGO.assignRegionCounters(GlobalDecl(OMD), CurFn);
807 assert(isa<CompoundStmt>(OMD->getBody()))(static_cast <bool> (isa<CompoundStmt>(OMD->getBody
())) ? void (0) : __assert_fail ("isa<CompoundStmt>(OMD->getBody())"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 807, __extension__ __PRETTY_FUNCTION__))
;
808 incrementProfileCounter(OMD->getBody());
809 EmitCompoundStmtWithoutScope(*cast<CompoundStmt>(OMD->getBody()));
810 FinishFunction(OMD->getBodyRBrace());
811}
812
813/// emitStructGetterCall - Call the runtime function to load a property
814/// into the return value slot.
815static void emitStructGetterCall(CodeGenFunction &CGF, ObjCIvarDecl *ivar,
816 bool isAtomic, bool hasStrong) {
817 ASTContext &Context = CGF.getContext();
818
819 Address src =
820 CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), CGF.LoadObjCSelf(), ivar, 0)
821 .getAddress(CGF);
822
823 // objc_copyStruct (ReturnValue, &structIvar,
824 // sizeof (Type of Ivar), isAtomic, false);
825 CallArgList args;
826
827 Address dest = CGF.Builder.CreateBitCast(CGF.ReturnValue, CGF.VoidPtrTy);
828 args.add(RValue::get(dest.getPointer()), Context.VoidPtrTy);
829
830 src = CGF.Builder.CreateBitCast(src, CGF.VoidPtrTy);
831 args.add(RValue::get(src.getPointer()), Context.VoidPtrTy);
832
833 CharUnits size = CGF.getContext().getTypeSizeInChars(ivar->getType());
834 args.add(RValue::get(CGF.CGM.getSize(size)), Context.getSizeType());
835 args.add(RValue::get(CGF.Builder.getInt1(isAtomic)), Context.BoolTy);
836 args.add(RValue::get(CGF.Builder.getInt1(hasStrong)), Context.BoolTy);
837
838 llvm::FunctionCallee fn = CGF.CGM.getObjCRuntime().GetGetStructFunction();
839 CGCallee callee = CGCallee::forDirect(fn);
840 CGF.EmitCall(CGF.getTypes().arrangeBuiltinFunctionCall(Context.VoidTy, args),
841 callee, ReturnValueSlot(), args);
842}
843
844/// Determine whether the given architecture supports unaligned atomic
845/// accesses. They don't have to be fast, just faster than a function
846/// call and a mutex.
847static bool hasUnalignedAtomics(llvm::Triple::ArchType arch) {
848 // FIXME: Allow unaligned atomic load/store on x86. (It is not
849 // currently supported by the backend.)
850 return 0;
851}
852
853/// Return the maximum size that permits atomic accesses for the given
854/// architecture.
855static CharUnits getMaxAtomicAccessSize(CodeGenModule &CGM,
856 llvm::Triple::ArchType arch) {
857 // ARM has 8-byte atomic accesses, but it's not clear whether we
858 // want to rely on them here.
859
860 // In the default case, just assume that any size up to a pointer is
861 // fine given adequate alignment.
862 return CharUnits::fromQuantity(CGM.PointerSizeInBytes);
863}
864
865namespace {
866 class PropertyImplStrategy {
867 public:
868 enum StrategyKind {
869 /// The 'native' strategy is to use the architecture's provided
870 /// reads and writes.
871 Native,
872
873 /// Use objc_setProperty and objc_getProperty.
874 GetSetProperty,
875
876 /// Use objc_setProperty for the setter, but use expression
877 /// evaluation for the getter.
878 SetPropertyAndExpressionGet,
879
880 /// Use objc_copyStruct.
881 CopyStruct,
882
883 /// The 'expression' strategy is to emit normal assignment or
884 /// lvalue-to-rvalue expressions.
885 Expression
886 };
887
888 StrategyKind getKind() const { return StrategyKind(Kind); }
889
890 bool hasStrongMember() const { return HasStrong; }
891 bool isAtomic() const { return IsAtomic; }
892 bool isCopy() const { return IsCopy; }
893
894 CharUnits getIvarSize() const { return IvarSize; }
895 CharUnits getIvarAlignment() const { return IvarAlignment; }
896
897 PropertyImplStrategy(CodeGenModule &CGM,
898 const ObjCPropertyImplDecl *propImpl);
899
900 private:
901 unsigned Kind : 8;
902 unsigned IsAtomic : 1;
903 unsigned IsCopy : 1;
904 unsigned HasStrong : 1;
905
906 CharUnits IvarSize;
907 CharUnits IvarAlignment;
908 };
909}
910
911/// Pick an implementation strategy for the given property synthesis.
912PropertyImplStrategy::PropertyImplStrategy(CodeGenModule &CGM,
913 const ObjCPropertyImplDecl *propImpl) {
914 const ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
915 ObjCPropertyDecl::SetterKind setterKind = prop->getSetterKind();
916
917 IsCopy = (setterKind == ObjCPropertyDecl::Copy);
918 IsAtomic = prop->isAtomic();
919 HasStrong = false; // doesn't matter here.
920
921 // Evaluate the ivar's size and alignment.
922 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
923 QualType ivarType = ivar->getType();
924 auto TInfo = CGM.getContext().getTypeInfoInChars(ivarType);
925 IvarSize = TInfo.Width;
926 IvarAlignment = TInfo.Align;
927
928 // If we have a copy property, we always have to use setProperty.
929 // If the property is atomic we need to use getProperty, but in
930 // the nonatomic case we can just use expression.
931 if (IsCopy) {
932 Kind = IsAtomic ? GetSetProperty : SetPropertyAndExpressionGet;
933 return;
934 }
935
936 // Handle retain.
937 if (setterKind == ObjCPropertyDecl::Retain) {
938 // In GC-only, there's nothing special that needs to be done.
939 if (CGM.getLangOpts().getGC() == LangOptions::GCOnly) {
940 // fallthrough
941
942 // In ARC, if the property is non-atomic, use expression emission,
943 // which translates to objc_storeStrong. This isn't required, but
944 // it's slightly nicer.
945 } else if (CGM.getLangOpts().ObjCAutoRefCount && !IsAtomic) {
946 // Using standard expression emission for the setter is only
947 // acceptable if the ivar is __strong, which won't be true if
948 // the property is annotated with __attribute__((NSObject)).
949 // TODO: falling all the way back to objc_setProperty here is
950 // just laziness, though; we could still use objc_storeStrong
951 // if we hacked it right.
952 if (ivarType.getObjCLifetime() == Qualifiers::OCL_Strong)
953 Kind = Expression;
954 else
955 Kind = SetPropertyAndExpressionGet;
956 return;
957
958 // Otherwise, we need to at least use setProperty. However, if
959 // the property isn't atomic, we can use normal expression
960 // emission for the getter.
961 } else if (!IsAtomic) {
962 Kind = SetPropertyAndExpressionGet;
963 return;
964
965 // Otherwise, we have to use both setProperty and getProperty.
966 } else {
967 Kind = GetSetProperty;
968 return;
969 }
970 }
971
972 // If we're not atomic, just use expression accesses.
973 if (!IsAtomic) {
974 Kind = Expression;
975 return;
976 }
977
978 // Properties on bitfield ivars need to be emitted using expression
979 // accesses even if they're nominally atomic.
980 if (ivar->isBitField()) {
981 Kind = Expression;
982 return;
983 }
984
985 // GC-qualified or ARC-qualified ivars need to be emitted as
986 // expressions. This actually works out to being atomic anyway,
987 // except for ARC __strong, but that should trigger the above code.
988 if (ivarType.hasNonTrivialObjCLifetime() ||
989 (CGM.getLangOpts().getGC() &&
990 CGM.getContext().getObjCGCAttrKind(ivarType))) {
991 Kind = Expression;
992 return;
993 }
994
995 // Compute whether the ivar has strong members.
996 if (CGM.getLangOpts().getGC())
997 if (const RecordType *recordType = ivarType->getAs<RecordType>())
998 HasStrong = recordType->getDecl()->hasObjectMember();
999
1000 // We can never access structs with object members with a native
1001 // access, because we need to use write barriers. This is what
1002 // objc_copyStruct is for.
1003 if (HasStrong) {
1004 Kind = CopyStruct;
1005 return;
1006 }
1007
1008 // Otherwise, this is target-dependent and based on the size and
1009 // alignment of the ivar.
1010
1011 // If the size of the ivar is not a power of two, give up. We don't
1012 // want to get into the business of doing compare-and-swaps.
1013 if (!IvarSize.isPowerOfTwo()) {
1014 Kind = CopyStruct;
1015 return;
1016 }
1017
1018 llvm::Triple::ArchType arch =
1019 CGM.getTarget().getTriple().getArch();
1020
1021 // Most architectures require memory to fit within a single cache
1022 // line, so the alignment has to be at least the size of the access.
1023 // Otherwise we have to grab a lock.
1024 if (IvarAlignment < IvarSize && !hasUnalignedAtomics(arch)) {
1025 Kind = CopyStruct;
1026 return;
1027 }
1028
1029 // If the ivar's size exceeds the architecture's maximum atomic
1030 // access size, we have to use CopyStruct.
1031 if (IvarSize > getMaxAtomicAccessSize(CGM, arch)) {
1032 Kind = CopyStruct;
1033 return;
1034 }
1035
1036 // Otherwise, we can use native loads and stores.
1037 Kind = Native;
1038}
1039
1040/// Generate an Objective-C property getter function.
1041///
1042/// The given Decl must be an ObjCImplementationDecl. \@synthesize
1043/// is illegal within a category.
1044void CodeGenFunction::GenerateObjCGetter(ObjCImplementationDecl *IMP,
1045 const ObjCPropertyImplDecl *PID) {
1046 llvm::Constant *AtomicHelperFn =
1047 CodeGenFunction(CGM).GenerateObjCAtomicGetterCopyHelperFunction(PID);
1048 ObjCMethodDecl *OMD = PID->getGetterMethodDecl();
1049 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)\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 1049, __extension__ __PRETTY_FUNCTION__))
;
1050 StartObjCMethod(OMD, IMP->getClassInterface());
1051
1052 generateObjCGetterBody(IMP, PID, OMD, AtomicHelperFn);
1053
1054 FinishFunction(OMD->getEndLoc());
1055}
1056
1057static bool hasTrivialGetExpr(const ObjCPropertyImplDecl *propImpl) {
1058 const Expr *getter = propImpl->getGetterCXXConstructor();
1059 if (!getter) return true;
1060
1061 // Sema only makes only of these when the ivar has a C++ class type,
1062 // so the form is pretty constrained.
1063
1064 // If the property has a reference type, we might just be binding a
1065 // reference, in which case the result will be a gl-value. We should
1066 // treat this as a non-trivial operation.
1067 if (getter->isGLValue())
1068 return false;
1069
1070 // If we selected a trivial copy-constructor, we're okay.
1071 if (const CXXConstructExpr *construct = dyn_cast<CXXConstructExpr>(getter))
1072 return (construct->getConstructor()->isTrivial());
1073
1074 // The constructor might require cleanups (in which case it's never
1075 // trivial).
1076 assert(isa<ExprWithCleanups>(getter))(static_cast <bool> (isa<ExprWithCleanups>(getter
)) ? void (0) : __assert_fail ("isa<ExprWithCleanups>(getter)"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 1076, __extension__ __PRETTY_FUNCTION__))
;
1077 return false;
1078}
1079
1080/// emitCPPObjectAtomicGetterCall - Call the runtime function to
1081/// copy the ivar into the resturn slot.
1082static void emitCPPObjectAtomicGetterCall(CodeGenFunction &CGF,
1083 llvm::Value *returnAddr,
1084 ObjCIvarDecl *ivar,
1085 llvm::Constant *AtomicHelperFn) {
1086 // objc_copyCppObjectAtomic (&returnSlot, &CppObjectIvar,
1087 // AtomicHelperFn);
1088 CallArgList args;
1089
1090 // The 1st argument is the return Slot.
1091 args.add(RValue::get(returnAddr), CGF.getContext().VoidPtrTy);
1092
1093 // The 2nd argument is the address of the ivar.
1094 llvm::Value *ivarAddr =
1095 CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), CGF.LoadObjCSelf(), ivar, 0)
1096 .getPointer(CGF);
1097 ivarAddr = CGF.Builder.CreateBitCast(ivarAddr, CGF.Int8PtrTy);
1098 args.add(RValue::get(ivarAddr), CGF.getContext().VoidPtrTy);
1099
1100 // Third argument is the helper function.
1101 args.add(RValue::get(AtomicHelperFn), CGF.getContext().VoidPtrTy);
1102
1103 llvm::FunctionCallee copyCppAtomicObjectFn =
1104 CGF.CGM.getObjCRuntime().GetCppAtomicObjectGetFunction();
1105 CGCallee callee = CGCallee::forDirect(copyCppAtomicObjectFn);
1106 CGF.EmitCall(
1107 CGF.getTypes().arrangeBuiltinFunctionCall(CGF.getContext().VoidTy, args),
1108 callee, ReturnValueSlot(), args);
1109}
1110
1111void
1112CodeGenFunction::generateObjCGetterBody(const ObjCImplementationDecl *classImpl,
1113 const ObjCPropertyImplDecl *propImpl,
1114 const ObjCMethodDecl *GetterMethodDecl,
1115 llvm::Constant *AtomicHelperFn) {
1116 // If there's a non-trivial 'get' expression, we just have to emit that.
1117 if (!hasTrivialGetExpr(propImpl)) {
1118 if (!AtomicHelperFn) {
1119 auto *ret = ReturnStmt::Create(getContext(), SourceLocation(),
1120 propImpl->getGetterCXXConstructor(),
1121 /* NRVOCandidate=*/nullptr);
1122 EmitReturnStmt(*ret);
1123 }
1124 else {
1125 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
1126 emitCPPObjectAtomicGetterCall(*this, ReturnValue.getPointer(),
1127 ivar, AtomicHelperFn);
1128 }
1129 return;
1130 }
1131
1132 const ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
1133 QualType propType = prop->getType();
1134 ObjCMethodDecl *getterMethod = propImpl->getGetterMethodDecl();
1135
1136 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
1137
1138 // Pick an implementation strategy.
1139 PropertyImplStrategy strategy(CGM, propImpl);
1140 switch (strategy.getKind()) {
1141 case PropertyImplStrategy::Native: {
1142 // We don't need to do anything for a zero-size struct.
1143 if (strategy.getIvarSize().isZero())
1144 return;
1145
1146 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar, 0);
1147
1148 // Currently, all atomic accesses have to be through integer
1149 // types, so there's no point in trying to pick a prettier type.
1150 uint64_t ivarSize = getContext().toBits(strategy.getIvarSize());
1151 llvm::Type *bitcastType = llvm::Type::getIntNTy(getLLVMContext(), ivarSize);
1152 bitcastType = bitcastType->getPointerTo(); // addrspace 0 okay
1153
1154 // Perform an atomic load. This does not impose ordering constraints.
1155 Address ivarAddr = LV.getAddress(*this);
1156 ivarAddr = Builder.CreateBitCast(ivarAddr, bitcastType);
1157 llvm::LoadInst *load = Builder.CreateLoad(ivarAddr, "load");
1158 load->setAtomic(llvm::AtomicOrdering::Unordered);
1159
1160 // Store that value into the return address. Doing this with a
1161 // bitcast is likely to produce some pretty ugly IR, but it's not
1162 // the *most* terrible thing in the world.
1163 llvm::Type *retTy = ConvertType(getterMethod->getReturnType());
1164 uint64_t retTySize = CGM.getDataLayout().getTypeSizeInBits(retTy);
1165 llvm::Value *ivarVal = load;
1166 if (ivarSize > retTySize) {
1167 llvm::Type *newTy = llvm::Type::getIntNTy(getLLVMContext(), retTySize);
1168 ivarVal = Builder.CreateTrunc(load, newTy);
1169 bitcastType = newTy->getPointerTo();
1170 }
1171 Builder.CreateStore(ivarVal,
1172 Builder.CreateBitCast(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", "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 1281)
;
1282 }
1283
1284 }
1285 llvm_unreachable("bad @property implementation strategy!")::llvm::llvm_unreachable_internal("bad @property implementation strategy!"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/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)"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/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 }
1559 ImplicitCastExpr argCast(ImplicitCastExpr::OnStack, ivarRef.getType(), argCK,
1560 &argLoad, VK_PRValue, FPOptionsOverride());
1561 Expr *finalArg = &argLoad;
1562 if (!getContext().hasSameUnqualifiedType(ivarRef.getType(),
1563 argLoad.getType()))
1564 finalArg = &argCast;
1565
1566 BinaryOperator *assign = BinaryOperator::Create(
1567 getContext(), &ivarRef, finalArg, BO_Assign, ivarRef.getType(),
1568 VK_PRValue, OK_Ordinary, SourceLocation(), FPOptionsOverride());
1569 EmitStmt(assign);
1570}
1571
1572/// Generate an Objective-C property setter function.
1573///
1574/// The given Decl must be an ObjCImplementationDecl. \@synthesize
1575/// is illegal within a category.
1576void CodeGenFunction::GenerateObjCSetter(ObjCImplementationDecl *IMP,
1577 const ObjCPropertyImplDecl *PID) {
1578 llvm::Constant *AtomicHelperFn =
1579 CodeGenFunction(CGM).GenerateObjCAtomicSetterCopyHelperFunction(PID);
1580 ObjCMethodDecl *OMD = PID->getSetterMethodDecl();
1581 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)\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 1581, __extension__ __PRETTY_FUNCTION__))
;
1582 StartObjCMethod(OMD, IMP->getClassInterface());
1583
1584 generateObjCSetterBody(IMP, PID, AtomicHelperFn);
1585
1586 FinishFunction(OMD->getEndLoc());
1587}
1588
1589namespace {
1590 struct DestroyIvar final : EHScopeStack::Cleanup {
1591 private:
1592 llvm::Value *addr;
1593 const ObjCIvarDecl *ivar;
1594 CodeGenFunction::Destroyer *destroyer;
1595 bool useEHCleanupForArray;
1596 public:
1597 DestroyIvar(llvm::Value *addr, const ObjCIvarDecl *ivar,
1598 CodeGenFunction::Destroyer *destroyer,
1599 bool useEHCleanupForArray)
1600 : addr(addr), ivar(ivar), destroyer(destroyer),
1601 useEHCleanupForArray(useEHCleanupForArray) {}
1602
1603 void Emit(CodeGenFunction &CGF, Flags flags) override {
1604 LValue lvalue
1605 = CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), addr, ivar, /*CVR*/ 0);
1606 CGF.emitDestroy(lvalue.getAddress(CGF), ivar->getType(), destroyer,
1607 flags.isForNormalCleanup() && useEHCleanupForArray);
1608 }
1609 };
1610}
1611
1612/// Like CodeGenFunction::destroyARCStrong, but do it with a call.
1613static void destroyARCStrongWithStore(CodeGenFunction &CGF,
1614 Address addr,
1615 QualType type) {
1616 llvm::Value *null = getNullForVariable(addr);
1617 CGF.EmitARCStoreStrongCall(addr, null, /*ignored*/ true);
1618}
1619
1620static void emitCXXDestructMethod(CodeGenFunction &CGF,
1621 ObjCImplementationDecl *impl) {
1622 CodeGenFunction::RunCleanupsScope scope(CGF);
1623
1624 llvm::Value *self = CGF.LoadObjCSelf();
1625
1626 const ObjCInterfaceDecl *iface = impl->getClassInterface();
1627 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
1628 ivar; ivar = ivar->getNextIvar()) {
1629 QualType type = ivar->getType();
1630
1631 // Check whether the ivar is a destructible type.
1632 QualType::DestructionKind dtorKind = type.isDestructedType();
1633 if (!dtorKind) continue;
1634
1635 CodeGenFunction::Destroyer *destroyer = nullptr;
1636
1637 // Use a call to objc_storeStrong to destroy strong ivars, for the
1638 // general benefit of the tools.
1639 if (dtorKind == QualType::DK_objc_strong_lifetime) {
1640 destroyer = destroyARCStrongWithStore;
1641
1642 // Otherwise use the default for the destruction kind.
1643 } else {
1644 destroyer = CGF.getDestroyer(dtorKind);
1645 }
1646
1647 CleanupKind cleanupKind = CGF.getCleanupKind(dtorKind);
1648
1649 CGF.EHStack.pushCleanup<DestroyIvar>(cleanupKind, self, ivar, destroyer,
1650 cleanupKind & EHCleanup);
1651 }
1652
1653 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?\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 1653, __extension__ __PRETTY_FUNCTION__))
;
1654}
1655
1656void CodeGenFunction::GenerateObjCCtorDtorMethod(ObjCImplementationDecl *IMP,
1657 ObjCMethodDecl *MD,
1658 bool ctor) {
1659 MD->createImplicitParams(CGM.getContext(), IMP->getClassInterface());
1660 StartObjCMethod(MD, IMP->getClassInterface());
1661
1662 // Emit .cxx_construct.
1663 if (ctor) {
1664 // Suppress the final autorelease in ARC.
1665 AutoreleaseResult = false;
1666
1667 for (const auto *IvarInit : IMP->inits()) {
1668 FieldDecl *Field = IvarInit->getAnyMember();
1669 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(Field);
1670 LValue LV = EmitLValueForIvar(TypeOfSelfObject(),
1671 LoadObjCSelf(), Ivar, 0);
1672 EmitAggExpr(IvarInit->getInit(),
1673 AggValueSlot::forLValue(LV, *this, AggValueSlot::IsDestructed,
1674 AggValueSlot::DoesNotNeedGCBarriers,
1675 AggValueSlot::IsNotAliased,
1676 AggValueSlot::DoesNotOverlap));
1677 }
1678 // constructor returns 'self'.
1679 CodeGenTypes &Types = CGM.getTypes();
1680 QualType IdTy(CGM.getContext().getObjCIdType());
1681 llvm::Value *SelfAsId =
1682 Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy));
1683 EmitReturnOfRValue(RValue::get(SelfAsId), IdTy);
1684
1685 // Emit .cxx_destruct.
1686 } else {
1687 emitCXXDestructMethod(*this, IMP);
1688 }
1689 FinishFunction();
1690}
1691
1692llvm::Value *CodeGenFunction::LoadObjCSelf() {
1693 VarDecl *Self = cast<ObjCMethodDecl>(CurFuncDecl)->getSelfDecl();
1694 DeclRefExpr DRE(getContext(), Self,
1695 /*is enclosing local*/ (CurFuncDecl != CurCodeDecl),
1696 Self->getType(), VK_LValue, SourceLocation());
1697 return EmitLoadOfScalar(EmitDeclRefLValue(&DRE), SourceLocation());
1698}
1699
1700QualType CodeGenFunction::TypeOfSelfObject() {
1701 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
1702 ImplicitParamDecl *selfDecl = OMD->getSelfDecl();
1703 const ObjCObjectPointerType *PTy = cast<ObjCObjectPointerType>(
1704 getContext().getCanonicalType(selfDecl->getType()));
1705 return PTy->getPointeeType();
1706}
1707
1708void CodeGenFunction::EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S){
1709 llvm::FunctionCallee EnumerationMutationFnPtr =
1710 CGM.getObjCRuntime().EnumerationMutationFunction();
1711 if (!EnumerationMutationFnPtr) {
1712 CGM.ErrorUnsupported(&S, "Obj-C fast enumeration for this runtime");
1713 return;
1714 }
1715 CGCallee EnumerationMutationFn =
1716 CGCallee::forDirect(EnumerationMutationFnPtr);
1717
1718 CGDebugInfo *DI = getDebugInfo();
1719 if (DI)
1720 DI->EmitLexicalBlockStart(Builder, S.getSourceRange().getBegin());
1721
1722 RunCleanupsScope ForScope(*this);
1723
1724 // The local variable comes into scope immediately.
1725 AutoVarEmission variable = AutoVarEmission::invalid();
1726 if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement()))
1727 variable = EmitAutoVarAlloca(*cast<VarDecl>(SD->getSingleDecl()));
1728
1729 JumpDest LoopEnd = getJumpDestInCurrentScope("forcoll.end");
1730
1731 // Fast enumeration state.
1732 QualType StateTy = CGM.getObjCFastEnumerationStateType();
1733 Address StatePtr = CreateMemTemp(StateTy, "state.ptr");
1734 EmitNullInitialization(StatePtr, StateTy);
1735
1736 // Number of elements in the items array.
1737 static const unsigned NumItems = 16;
1738
1739 // Fetch the countByEnumeratingWithState:objects:count: selector.
1740 IdentifierInfo *II[] = {
1741 &CGM.getContext().Idents.get("countByEnumeratingWithState"),
1742 &CGM.getContext().Idents.get("objects"),
1743 &CGM.getContext().Idents.get("count")
1744 };
1745 Selector FastEnumSel =
1746 CGM.getContext().Selectors.getSelector(llvm::array_lengthof(II), &II[0]);
1747
1748 QualType ItemsTy =
1749 getContext().getConstantArrayType(getContext().getObjCIdType(),
1750 llvm::APInt(32, NumItems), nullptr,
1751 ArrayType::Normal, 0);
1752 Address ItemsPtr = CreateMemTemp(ItemsTy, "items.ptr");
1753
1754 // Emit the collection pointer. In ARC, we do a retain.
1755 llvm::Value *Collection;
1756 if (getLangOpts().ObjCAutoRefCount) {
1757 Collection = EmitARCRetainScalarExpr(S.getCollection());
1758
1759 // Enter a cleanup to do the release.
1760 EmitObjCConsumeObject(S.getCollection()->getType(), Collection);
1761 } else {
1762 Collection = EmitScalarExpr(S.getCollection());
1763 }
1764
1765 // The 'continue' label needs to appear within the cleanup for the
1766 // collection object.
1767 JumpDest AfterBody = getJumpDestInCurrentScope("forcoll.next");
1768
1769 // Send it our message:
1770 CallArgList Args;
1771
1772 // The first argument is a temporary of the enumeration-state type.
1773 Args.add(RValue::get(StatePtr.getPointer()),
1774 getContext().getPointerType(StateTy));
1775
1776 // The second argument is a temporary array with space for NumItems
1777 // pointers. We'll actually be loading elements from the array
1778 // pointer written into the control state; this buffer is so that
1779 // collections that *aren't* backed by arrays can still queue up
1780 // batches of elements.
1781 Args.add(RValue::get(ItemsPtr.getPointer()),
1782 getContext().getPointerType(ItemsTy));
1783
1784 // The third argument is the capacity of that temporary array.
1785 llvm::Type *NSUIntegerTy = ConvertType(getContext().getNSUIntegerType());
1786 llvm::Constant *Count = llvm::ConstantInt::get(NSUIntegerTy, NumItems);
1787 Args.add(RValue::get(Count), getContext().getNSUIntegerType());
1788
1789 // Start the enumeration.
1790 RValue CountRV =
1791 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
1792 getContext().getNSUIntegerType(),
1793 FastEnumSel, Collection, Args);
1794
1795 // The initial number of objects that were returned in the buffer.
1796 llvm::Value *initialBufferLimit = CountRV.getScalarVal();
1797
1798 llvm::BasicBlock *EmptyBB = createBasicBlock("forcoll.empty");
1799 llvm::BasicBlock *LoopInitBB = createBasicBlock("forcoll.loopinit");
1800
1801 llvm::Value *zero = llvm::Constant::getNullValue(NSUIntegerTy);
1802
1803 // If the limit pointer was zero to begin with, the collection is
1804 // empty; skip all this. Set the branch weight assuming this has the same
1805 // probability of exiting the loop as any other loop exit.
1806 uint64_t EntryCount = getCurrentProfileCount();
1807 Builder.CreateCondBr(
1808 Builder.CreateICmpEQ(initialBufferLimit, zero, "iszero"), EmptyBB,
1809 LoopInitBB,
1810 createProfileWeights(EntryCount, getProfileCount(S.getBody())));
1811
1812 // Otherwise, initialize the loop.
1813 EmitBlock(LoopInitBB);
1814
1815 // Save the initial mutations value. This is the value at an
1816 // address that was written into the state object by
1817 // countByEnumeratingWithState:objects:count:.
1818 Address StateMutationsPtrPtr =
1819 Builder.CreateStructGEP(StatePtr, 2, "mutationsptr.ptr");
1820 llvm::Value *StateMutationsPtr
1821 = Builder.CreateLoad(StateMutationsPtrPtr, "mutationsptr");
1822
1823 llvm::Type *UnsignedLongTy = ConvertType(getContext().UnsignedLongTy);
1824 llvm::Value *initialMutations =
1825 Builder.CreateAlignedLoad(UnsignedLongTy, StateMutationsPtr,
1826 getPointerAlign(), "forcoll.initial-mutations");
1827
1828 // Start looping. This is the point we return to whenever we have a
1829 // fresh, non-empty batch of objects.
1830 llvm::BasicBlock *LoopBodyBB = createBasicBlock("forcoll.loopbody");
1831 EmitBlock(LoopBodyBB);
1832
1833 // The current index into the buffer.
1834 llvm::PHINode *index = Builder.CreatePHI(NSUIntegerTy, 3, "forcoll.index");
1835 index->addIncoming(zero, LoopInitBB);
1836
1837 // The current buffer size.
1838 llvm::PHINode *count = Builder.CreatePHI(NSUIntegerTy, 3, "forcoll.count");
1839 count->addIncoming(initialBufferLimit, LoopInitBB);
1840
1841 incrementProfileCounter(&S);
1842
1843 // Check whether the mutations value has changed from where it was
1844 // at start. StateMutationsPtr should actually be invariant between
1845 // refreshes.
1846 StateMutationsPtr = Builder.CreateLoad(StateMutationsPtrPtr, "mutationsptr");
1847 llvm::Value *currentMutations
1848 = Builder.CreateAlignedLoad(UnsignedLongTy, StateMutationsPtr,
1849 getPointerAlign(), "statemutations");
1850
1851 llvm::BasicBlock *WasMutatedBB = createBasicBlock("forcoll.mutated");
1852 llvm::BasicBlock *WasNotMutatedBB = createBasicBlock("forcoll.notmutated");
1853
1854 Builder.CreateCondBr(Builder.CreateICmpEQ(currentMutations, initialMutations),
1855 WasNotMutatedBB, WasMutatedBB);
1856
1857 // If so, call the enumeration-mutation function.
1858 EmitBlock(WasMutatedBB);
1859 llvm::Type *ObjCIdType = ConvertType(getContext().getObjCIdType());
1860 llvm::Value *V =
1861 Builder.CreateBitCast(Collection, ObjCIdType);
1862 CallArgList Args2;
1863 Args2.add(RValue::get(V), getContext().getObjCIdType());
1864 // FIXME: We shouldn't need to get the function info here, the runtime already
1865 // should have computed it to build the function.
1866 EmitCall(
1867 CGM.getTypes().arrangeBuiltinFunctionCall(getContext().VoidTy, Args2),
1868 EnumerationMutationFn, ReturnValueSlot(), Args2);
1869
1870 // Otherwise, or if the mutation function returns, just continue.
1871 EmitBlock(WasNotMutatedBB);
1872
1873 // Initialize the element variable.
1874 RunCleanupsScope elementVariableScope(*this);
1875 bool elementIsVariable;
1876 LValue elementLValue;
1877 QualType elementType;
1878 if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement())) {
1879 // Initialize the variable, in case it's a __block variable or something.
1880 EmitAutoVarInit(variable);
1881
1882 const VarDecl *D = cast<VarDecl>(SD->getSingleDecl());
1883 DeclRefExpr tempDRE(getContext(), const_cast<VarDecl *>(D), false,
1884 D->getType(), VK_LValue, SourceLocation());
1885 elementLValue = EmitLValue(&tempDRE);
1886 elementType = D->getType();
1887 elementIsVariable = true;
1888
1889 if (D->isARCPseudoStrong())
1890 elementLValue.getQuals().setObjCLifetime(Qualifiers::OCL_ExplicitNone);
1891 } else {
1892 elementLValue = LValue(); // suppress warning
1893 elementType = cast<Expr>(S.getElement())->getType();
1894 elementIsVariable = false;
1895 }
1896 llvm::Type *convertedElementType = ConvertType(elementType);
1897
1898 // Fetch the buffer out of the enumeration state.
1899 // TODO: this pointer should actually be invariant between
1900 // refreshes, which would help us do certain loop optimizations.
1901 Address StateItemsPtr =
1902 Builder.CreateStructGEP(StatePtr, 1, "stateitems.ptr");
1903 llvm::Value *EnumStateItems =
1904 Builder.CreateLoad(StateItemsPtr, "stateitems");
1905
1906 // Fetch the value at the current index from the buffer.
1907 llvm::Value *CurrentItemPtr = Builder.CreateGEP(
1908 EnumStateItems->getType()->getPointerElementType(), EnumStateItems, index,
1909 "currentitem.ptr");
1910 llvm::Value *CurrentItem =
1911 Builder.CreateAlignedLoad(ObjCIdType, CurrentItemPtr, getPointerAlign());
1912
1913 if (SanOpts.has(SanitizerKind::ObjCCast)) {
1914 // Before using an item from the collection, check that the implicit cast
1915 // from id to the element type is valid. This is done with instrumentation
1916 // roughly corresponding to:
1917 //
1918 // if (![item isKindOfClass:expectedCls]) { /* emit diagnostic */ }
1919 const ObjCObjectPointerType *ObjPtrTy =
1920 elementType->getAsObjCInterfacePointerType();
1921 const ObjCInterfaceType *InterfaceTy =
1922 ObjPtrTy ? ObjPtrTy->getInterfaceType() : nullptr;
1923 if (InterfaceTy) {
1924 SanitizerScope SanScope(this);
1925 auto &C = CGM.getContext();
1926 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\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 1926, __extension__ __PRETTY_FUNCTION__))
;
1927 Selector IsKindOfClassSel = GetUnarySelector("isKindOfClass", C);
1928 CallArgList IsKindOfClassArgs;
1929 llvm::Value *Cls =
1930 CGM.getObjCRuntime().GetClass(*this, InterfaceTy->getDecl());
1931 IsKindOfClassArgs.add(RValue::get(Cls), C.getObjCClassType());
1932 llvm::Value *IsClass =
1933 CGM.getObjCRuntime()
1934 .GenerateMessageSend(*this, ReturnValueSlot(), C.BoolTy,
1935 IsKindOfClassSel, CurrentItem,
1936 IsKindOfClassArgs)
1937 .getScalarVal();
1938 llvm::Constant *StaticData[] = {
1939 EmitCheckSourceLocation(S.getBeginLoc()),
1940 EmitCheckTypeDescriptor(QualType(InterfaceTy, 0))};
1941 EmitCheck({{IsClass, SanitizerKind::ObjCCast}},
1942 SanitizerHandler::InvalidObjCCast,
1943 ArrayRef<llvm::Constant *>(StaticData), CurrentItem);
1944 }
1945 }
1946
1947 // Cast that value to the right type.
1948 CurrentItem = Builder.CreateBitCast(CurrentItem, convertedElementType,
1949 "currentitem");
1950
1951 // Make sure we have an l-value. Yes, this gets evaluated every
1952 // time through the loop.
1953 if (!elementIsVariable) {
1954 elementLValue = EmitLValue(cast<Expr>(S.getElement()));
1955 EmitStoreThroughLValue(RValue::get(CurrentItem), elementLValue);
1956 } else {
1957 EmitStoreThroughLValue(RValue::get(CurrentItem), elementLValue,
1958 /*isInit*/ true);
1959 }
1960
1961 // If we do have an element variable, this assignment is the end of
1962 // its initialization.
1963 if (elementIsVariable)
1964 EmitAutoVarCleanups(variable);
1965
1966 // Perform the loop body, setting up break and continue labels.
1967 BreakContinueStack.push_back(BreakContinue(LoopEnd, AfterBody));
1968 {
1969 RunCleanupsScope Scope(*this);
1970 EmitStmt(S.getBody());
1971 }
1972 BreakContinueStack.pop_back();
1973
1974 // Destroy the element variable now.
1975 elementVariableScope.ForceCleanup();
1976
1977 // Check whether there are more elements.
1978 EmitBlock(AfterBody.getBlock());
1979
1980 llvm::BasicBlock *FetchMoreBB = createBasicBlock("forcoll.refetch");
1981
1982 // First we check in the local buffer.
1983 llvm::Value *indexPlusOne =
1984 Builder.CreateAdd(index, llvm::ConstantInt::get(NSUIntegerTy, 1));
1985
1986 // If we haven't overrun the buffer yet, we can continue.
1987 // Set the branch weights based on the simplifying assumption that this is
1988 // like a while-loop, i.e., ignoring that the false branch fetches more
1989 // elements and then returns to the loop.
1990 Builder.CreateCondBr(
1991 Builder.CreateICmpULT(indexPlusOne, count), LoopBodyBB, FetchMoreBB,
1992 createProfileWeights(getProfileCount(S.getBody()), EntryCount));
1993
1994 index->addIncoming(indexPlusOne, AfterBody.getBlock());
1995 count->addIncoming(count, AfterBody.getBlock());
1996
1997 // Otherwise, we have to fetch more elements.
1998 EmitBlock(FetchMoreBB);
1999
2000 CountRV =
2001 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
2002 getContext().getNSUIntegerType(),
2003 FastEnumSel, Collection, Args);
2004
2005 // If we got a zero count, we're done.
2006 llvm::Value *refetchCount = CountRV.getScalarVal();
2007
2008 // (note that the message send might split FetchMoreBB)
2009 index->addIncoming(zero, Builder.GetInsertBlock());
2010 count->addIncoming(refetchCount, Builder.GetInsertBlock());
2011
2012 Builder.CreateCondBr(Builder.CreateICmpEQ(refetchCount, zero),
2013 EmptyBB, LoopBodyBB);
2014
2015 // No more elements.
2016 EmitBlock(EmptyBB);
2017
2018 if (!elementIsVariable) {
2019 // If the element was not a declaration, set it to be null.
2020
2021 llvm::Value *null = llvm::Constant::getNullValue(convertedElementType);
2022 elementLValue = EmitLValue(cast<Expr>(S.getElement()));
2023 EmitStoreThroughLValue(RValue::get(null), elementLValue);
2024 }
2025
2026 if (DI)
2027 DI->EmitLexicalBlockEnd(Builder, S.getSourceRange().getEnd());
2028
2029 ForScope.ForceCleanup();
2030 EmitBlock(LoopEnd.getBlock());
2031}
2032
2033void CodeGenFunction::EmitObjCAtTryStmt(const ObjCAtTryStmt &S) {
2034 CGM.getObjCRuntime().EmitTryStmt(*this, S);
2035}
2036
2037void CodeGenFunction::EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S) {
2038 CGM.getObjCRuntime().EmitThrowStmt(*this, S);
2039}
2040
2041void CodeGenFunction::EmitObjCAtSynchronizedStmt(
2042 const ObjCAtSynchronizedStmt &S) {
2043 CGM.getObjCRuntime().EmitSynchronizedStmt(*this, S);
2044}
2045
2046namespace {
2047 struct CallObjCRelease final : EHScopeStack::Cleanup {
2048 CallObjCRelease(llvm::Value *object) : object(object) {}
2049 llvm::Value *object;
2050
2051 void Emit(CodeGenFunction &CGF, Flags flags) override {
2052 // Releases at the end of the full-expression are imprecise.
2053 CGF.EmitARCRelease(object, ARCImpreciseLifetime);
2054 }
2055 };
2056}
2057
2058/// Produce the code for a CK_ARCConsumeObject. Does a primitive
2059/// release at the end of the full-expression.
2060llvm::Value *CodeGenFunction::EmitObjCConsumeObject(QualType type,
2061 llvm::Value *object) {
2062 // If we're in a conditional branch, we need to make the cleanup
2063 // conditional.
2064 pushFullExprCleanup<CallObjCRelease>(getARCCleanupKind(), object);
2065 return object;
2066}
2067
2068llvm::Value *CodeGenFunction::EmitObjCExtendObjectLifetime(QualType type,
2069 llvm::Value *value) {
2070 return EmitARCRetainAutorelease(type, value);
2071}
2072
2073/// Given a number of pointers, inform the optimizer that they're
2074/// being intrinsically used up until this point in the program.
2075void CodeGenFunction::EmitARCIntrinsicUse(ArrayRef<llvm::Value*> values) {
2076 llvm::Function *&fn = CGM.getObjCEntrypoints().clang_arc_use;
2077 if (!fn)
2078 fn = CGM.getIntrinsic(llvm::Intrinsic::objc_clang_arc_use);
2079
2080 // This isn't really a "runtime" function, but as an intrinsic it
2081 // doesn't really matter as long as we align things up.
2082 EmitNounwindRuntimeCall(fn, values);
2083}
2084
2085/// Emit a call to "clang.arc.noop.use", which consumes the result of a call
2086/// that has operand bundle "clang.arc.attachedcall".
2087void CodeGenFunction::EmitARCNoopIntrinsicUse(ArrayRef<llvm::Value *> values) {
2088 llvm::Function *&fn = CGM.getObjCEntrypoints().clang_arc_noop_use;
2089 if (!fn)
2090 fn = CGM.getIntrinsic(llvm::Intrinsic::objc_clang_arc_noop_use);
2091 EmitNounwindRuntimeCall(fn, values);
2092}
2093
2094static void setARCRuntimeFunctionLinkage(CodeGenModule &CGM, llvm::Value *RTF) {
2095 if (auto *F = dyn_cast<llvm::Function>(RTF)) {
2096 // If the target runtime doesn't naturally support ARC, emit weak
2097 // references to the runtime support library. We don't really
2098 // permit this to fail, but we need a particular relocation style.
2099 if (!CGM.getLangOpts().ObjCRuntime.hasNativeARC() &&
2100 !CGM.getTriple().isOSBinFormatCOFF()) {
2101 F->setLinkage(llvm::Function::ExternalWeakLinkage);
2102 }
2103 }
2104}
2105
2106static void setARCRuntimeFunctionLinkage(CodeGenModule &CGM,
2107 llvm::FunctionCallee RTF) {
2108 setARCRuntimeFunctionLinkage(CGM, RTF.getCallee());
2109}
2110
2111/// Perform an operation having the signature
2112/// i8* (i8*)
2113/// where a null input causes a no-op and returns null.
2114static llvm::Value *emitARCValueOperation(
2115 CodeGenFunction &CGF, llvm::Value *value, llvm::Type *returnType,
2116 llvm::Function *&fn, llvm::Intrinsic::ID IntID,
2117 llvm::CallInst::TailCallKind tailKind = llvm::CallInst::TCK_None) {
2118 if (isa<llvm::ConstantPointerNull>(value))
2119 return value;
2120
2121 if (!fn) {
2122 fn = CGF.CGM.getIntrinsic(IntID);
2123 setARCRuntimeFunctionLinkage(CGF.CGM, fn);
2124 }
2125
2126 // Cast the argument to 'id'.
2127 llvm::Type *origType = returnType ? returnType : value->getType();
2128 value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy);
2129
2130 // Call the function.
2131 llvm::CallInst *call = CGF.EmitNounwindRuntimeCall(fn, value);
2132 call->setTailCallKind(tailKind);
2133
2134 // Cast the result back to the original type.
2135 return CGF.Builder.CreateBitCast(call, origType);
2136}
2137
2138/// Perform an operation having the following signature:
2139/// i8* (i8**)
2140static llvm::Value *emitARCLoadOperation(CodeGenFunction &CGF, Address addr,
2141 llvm::Function *&fn,
2142 llvm::Intrinsic::ID IntID) {
2143 if (!fn) {
2144 fn = CGF.CGM.getIntrinsic(IntID);
2145 setARCRuntimeFunctionLinkage(CGF.CGM, fn);
2146 }
2147
2148 // Cast the argument to 'id*'.
2149 llvm::Type *origType = addr.getElementType();
2150 addr = CGF.Builder.CreateBitCast(addr, CGF.Int8PtrPtrTy);
2151
2152 // Call the function.
2153 llvm::Value *result = CGF.EmitNounwindRuntimeCall(fn, addr.getPointer());
2154
2155 // Cast the result back to a dereference of the original type.
2156 if (origType != CGF.Int8PtrTy)
2157 result = CGF.Builder.CreateBitCast(result, origType);
2158
2159 return result;
2160}
2161
2162/// Perform an operation having the following signature:
2163/// i8* (i8**, i8*)
2164static llvm::Value *emitARCStoreOperation(CodeGenFunction &CGF, Address addr,
2165 llvm::Value *value,
2166 llvm::Function *&fn,
2167 llvm::Intrinsic::ID IntID,
2168 bool ignored) {
2169 assert(addr.getElementType() == value->getType())(static_cast <bool> (addr.getElementType() == value->
getType()) ? void (0) : __assert_fail ("addr.getElementType() == value->getType()"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 2169, __extension__ __PRETTY_FUNCTION__))
;
2170
2171 if (!fn) {
2172 fn = CGF.CGM.getIntrinsic(IntID);
2173 setARCRuntimeFunctionLinkage(CGF.CGM, fn);
2174 }
2175
2176 llvm::Type *origType = value->getType();
2177
2178 llvm::Value *args[] = {
2179 CGF.Builder.CreateBitCast(addr.getPointer(), CGF.Int8PtrPtrTy),
2180 CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy)
2181 };
2182 llvm::CallInst *result = CGF.EmitNounwindRuntimeCall(fn, args);
2183
2184 if (ignored) return nullptr;
2185
2186 return CGF.Builder.CreateBitCast(result, origType);
2187}
2188
2189/// Perform an operation having the following signature:
2190/// void (i8**, i8**)
2191static void emitARCCopyOperation(CodeGenFunction &CGF, Address dst, Address src,
2192 llvm::Function *&fn,
2193 llvm::Intrinsic::ID IntID) {
2194 assert(dst.getType() == src.getType())(static_cast <bool> (dst.getType() == src.getType()) ? void
(0) : __assert_fail ("dst.getType() == src.getType()", "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 2194, __extension__ __PRETTY_FUNCTION__))
;
2195
2196 if (!fn) {
2197 fn = CGF.CGM.getIntrinsic(IntID);
2198 setARCRuntimeFunctionLinkage(CGF.CGM, fn);
2199 }
2200
2201 llvm::Value *args[] = {
2202 CGF.Builder.CreateBitCast(dst.getPointer(), CGF.Int8PtrPtrTy),
2203 CGF.Builder.CreateBitCast(src.getPointer(), CGF.Int8PtrPtrTy)
2204 };
2205 CGF.EmitNounwindRuntimeCall(fn, args);
2206}
2207
2208/// Perform an operation having the signature
2209/// i8* (i8*)
2210/// where a null input causes a no-op and returns null.
2211static llvm::Value *emitObjCValueOperation(CodeGenFunction &CGF,
2212 llvm::Value *value,
2213 llvm::Type *returnType,
2214 llvm::FunctionCallee &fn,
2215 StringRef fnName) {
2216 if (isa<llvm::ConstantPointerNull>(value))
2217 return value;
2218
2219 if (!fn) {
2220 llvm::FunctionType *fnType =
2221 llvm::FunctionType::get(CGF.Int8PtrTy, CGF.Int8PtrTy, false);
2222 fn = CGF.CGM.CreateRuntimeFunction(fnType, fnName);
2223
2224 // We have Native ARC, so set nonlazybind attribute for performance
2225 if (llvm::Function *f = dyn_cast<llvm::Function>(fn.getCallee()))
2226 if (fnName == "objc_retain")
2227 f->addFnAttr(llvm::Attribute::NonLazyBind);
2228 }
2229
2230 // Cast the argument to 'id'.
2231 llvm::Type *origType = returnType ? returnType : value->getType();
2232 value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy);
2233
2234 // Call the function.
2235 llvm::CallBase *Inst = CGF.EmitCallOrInvoke(fn, value);
2236
2237 // Mark calls to objc_autorelease as tail on the assumption that methods
2238 // overriding autorelease do not touch anything on the stack.
2239 if (fnName == "objc_autorelease")
2240 if (auto *Call = dyn_cast<llvm::CallInst>(Inst))
2241 Call->setTailCall();
2242
2243 // Cast the result back to the original type.
2244 return CGF.Builder.CreateBitCast(Inst, origType);
2245}
2246
2247/// Produce the code to do a retain. Based on the type, calls one of:
2248/// call i8* \@objc_retain(i8* %value)
2249/// call i8* \@objc_retainBlock(i8* %value)
2250llvm::Value *CodeGenFunction::EmitARCRetain(QualType type, llvm::Value *value) {
2251 if (type->isBlockPointerType())
2252 return EmitARCRetainBlock(value, /*mandatory*/ false);
2253 else
2254 return EmitARCRetainNonBlock(value);
2255}
2256
2257/// Retain the given object, with normal retain semantics.
2258/// call i8* \@objc_retain(i8* %value)
2259llvm::Value *CodeGenFunction::EmitARCRetainNonBlock(llvm::Value *value) {
2260 return emitARCValueOperation(*this, value, nullptr,
2261 CGM.getObjCEntrypoints().objc_retain,
2262 llvm::Intrinsic::objc_retain);
2263}
2264
2265/// Retain the given block, with _Block_copy semantics.
2266/// call i8* \@objc_retainBlock(i8* %value)
2267///
2268/// \param mandatory - If false, emit the call with metadata
2269/// indicating that it's okay for the optimizer to eliminate this call
2270/// if it can prove that the block never escapes except down the stack.
2271llvm::Value *CodeGenFunction::EmitARCRetainBlock(llvm::Value *value,
2272 bool mandatory) {
2273 llvm::Value *result
2274 = emitARCValueOperation(*this, value, nullptr,
2275 CGM.getObjCEntrypoints().objc_retainBlock,
2276 llvm::Intrinsic::objc_retainBlock);
2277
2278 // If the copy isn't mandatory, add !clang.arc.copy_on_escape to
2279 // tell the optimizer that it doesn't need to do this copy if the
2280 // block doesn't escape, where being passed as an argument doesn't
2281 // count as escaping.
2282 if (!mandatory && isa<llvm::Instruction>(result)) {
2283 llvm::CallInst *call
2284 = cast<llvm::CallInst>(result->stripPointerCasts());
2285 assert(call->getCalledOperand() ==(static_cast <bool> (call->getCalledOperand() == CGM
.getObjCEntrypoints().objc_retainBlock) ? void (0) : __assert_fail
("call->getCalledOperand() == CGM.getObjCEntrypoints().objc_retainBlock"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 2286, __extension__ __PRETTY_FUNCTION__))
2286 CGM.getObjCEntrypoints().objc_retainBlock)(static_cast <bool> (call->getCalledOperand() == CGM
.getObjCEntrypoints().objc_retainBlock) ? void (0) : __assert_fail
("call->getCalledOperand() == CGM.getObjCEntrypoints().objc_retainBlock"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 2286, __extension__ __PRETTY_FUNCTION__))
;
2287
2288 call->setMetadata("clang.arc.copy_on_escape",
2289 llvm::MDNode::get(Builder.getContext(), None));
2290 }
2291
2292 return result;
2293}
2294
2295static void emitAutoreleasedReturnValueMarker(CodeGenFunction &CGF) {
2296 // Fetch the void(void) inline asm which marks that we're going to
2297 // do something with the autoreleased return value.
2298 llvm::InlineAsm *&marker
2299 = CGF.CGM.getObjCEntrypoints().retainAutoreleasedReturnValueMarker;
2300 if (!marker) {
2301 StringRef assembly
2302 = CGF.CGM.getTargetCodeGenInfo()
2303 .getARCRetainAutoreleasedReturnValueMarker();
2304
2305 // If we have an empty assembly string, there's nothing to do.
2306 if (assembly.empty()) {
2307
2308 // Otherwise, at -O0, build an inline asm that we're going to call
2309 // in a moment.
2310 } else if (CGF.CGM.getCodeGenOpts().OptimizationLevel == 0) {
2311 llvm::FunctionType *type =
2312 llvm::FunctionType::get(CGF.VoidTy, /*variadic*/false);
2313
2314 marker = llvm::InlineAsm::get(type, assembly, "", /*sideeffects*/ true);
2315
2316 // If we're at -O1 and above, we don't want to litter the code
2317 // with this marker yet, so leave a breadcrumb for the ARC
2318 // optimizer to pick up.
2319 } else {
2320 const char *retainRVMarkerKey = llvm::objcarc::getRVMarkerModuleFlagStr();
2321 if (!CGF.CGM.getModule().getModuleFlag(retainRVMarkerKey)) {
2322 auto *str = llvm::MDString::get(CGF.getLLVMContext(), assembly);
2323 CGF.CGM.getModule().addModuleFlag(llvm::Module::Error,
2324 retainRVMarkerKey, str);
2325 }
2326 }
2327 }
2328
2329 // Call the marker asm if we made one, which we do only at -O0.
2330 if (marker)
2331 CGF.Builder.CreateCall(marker, None, CGF.getBundlesForFunclet(marker));
2332}
2333
2334static llvm::Value *emitOptimizedARCReturnCall(llvm::Value *value,
2335 bool IsRetainRV,
2336 CodeGenFunction &CGF) {
2337 emitAutoreleasedReturnValueMarker(CGF);
2338
2339 // Add operand bundle "clang.arc.attachedcall" to the call instead of emitting
2340 // retainRV or claimRV calls in the IR. We currently do this only when the
2341 // optimization level isn't -O0 since global-isel, which is currently run at
2342 // -O0, doesn't know about the operand bundle.
2343
2344 // FIXME: Do this when the target isn't aarch64.
2345 if (CGF.CGM.getCodeGenOpts().OptimizationLevel > 0 &&
2346 CGF.CGM.getTarget().getTriple().isAArch64()) {
2347 llvm::Value *bundleArgs[] = {llvm::ConstantInt::get(
2348 CGF.Int64Ty,
2349 llvm::objcarc::getAttachedCallOperandBundleEnum(IsRetainRV))};
2350 llvm::OperandBundleDef OB("clang.arc.attachedcall", bundleArgs);
2351 auto *oldCall = cast<llvm::CallBase>(value);
2352 llvm::CallBase *newCall = llvm::CallBase::addOperandBundle(
2353 oldCall, llvm::LLVMContext::OB_clang_arc_attachedcall, OB, oldCall);
2354 newCall->copyMetadata(*oldCall);
2355 oldCall->replaceAllUsesWith(newCall);
2356 oldCall->eraseFromParent();
2357 CGF.EmitARCNoopIntrinsicUse(newCall);
2358 return newCall;
2359 }
2360
2361 bool isNoTail =
2362 CGF.CGM.getTargetCodeGenInfo().markARCOptimizedReturnCallsAsNoTail();
2363 llvm::CallInst::TailCallKind tailKind =
2364 isNoTail ? llvm::CallInst::TCK_NoTail : llvm::CallInst::TCK_None;
2365 ObjCEntrypoints &EPs = CGF.CGM.getObjCEntrypoints();
2366 llvm::Function *&EP = IsRetainRV
2367 ? EPs.objc_retainAutoreleasedReturnValue
2368 : EPs.objc_unsafeClaimAutoreleasedReturnValue;
2369 llvm::Intrinsic::ID IID =
2370 IsRetainRV ? llvm::Intrinsic::objc_retainAutoreleasedReturnValue
2371 : llvm::Intrinsic::objc_unsafeClaimAutoreleasedReturnValue;
2372 return emitARCValueOperation(CGF, value, nullptr, EP, IID, tailKind);
2373}
2374
2375/// Retain the given object which is the result of a function call.
2376/// call i8* \@objc_retainAutoreleasedReturnValue(i8* %value)
2377///
2378/// Yes, this function name is one character away from a different
2379/// call with completely different semantics.
2380llvm::Value *
2381CodeGenFunction::EmitARCRetainAutoreleasedReturnValue(llvm::Value *value) {
2382 return emitOptimizedARCReturnCall(value, true, *this);
2383}
2384
2385/// Claim a possibly-autoreleased return value at +0. This is only
2386/// valid to do in contexts which do not rely on the retain to keep
2387/// the object valid for all of its uses; for example, when
2388/// the value is ignored, or when it is being assigned to an
2389/// __unsafe_unretained variable.
2390///
2391/// call i8* \@objc_unsafeClaimAutoreleasedReturnValue(i8* %value)
2392llvm::Value *
2393CodeGenFunction::EmitARCUnsafeClaimAutoreleasedReturnValue(llvm::Value *value) {
2394 return emitOptimizedARCReturnCall(value, false, *this);
2395}
2396
2397/// Release the given object.
2398/// call void \@objc_release(i8* %value)
2399void CodeGenFunction::EmitARCRelease(llvm::Value *value,
2400 ARCPreciseLifetime_t precise) {
2401 if (isa<llvm::ConstantPointerNull>(value)) return;
2402
2403 llvm::Function *&fn = CGM.getObjCEntrypoints().objc_release;
2404 if (!fn) {
2405 fn = CGM.getIntrinsic(llvm::Intrinsic::objc_release);
2406 setARCRuntimeFunctionLinkage(CGM, fn);
2407 }
2408
2409 // Cast the argument to 'id'.
2410 value = Builder.CreateBitCast(value, Int8PtrTy);
2411
2412 // Call objc_release.
2413 llvm::CallInst *call = EmitNounwindRuntimeCall(fn, value);
2414
2415 if (precise == ARCImpreciseLifetime) {
2416 call->setMetadata("clang.imprecise_release",
2417 llvm::MDNode::get(Builder.getContext(), None));
2418 }
2419}
2420
2421/// Destroy a __strong variable.
2422///
2423/// At -O0, emit a call to store 'null' into the address;
2424/// instrumenting tools prefer this because the address is exposed,
2425/// but it's relatively cumbersome to optimize.
2426///
2427/// At -O1 and above, just load and call objc_release.
2428///
2429/// call void \@objc_storeStrong(i8** %addr, i8* null)
2430void CodeGenFunction::EmitARCDestroyStrong(Address addr,
2431 ARCPreciseLifetime_t precise) {
2432 if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
2433 llvm::Value *null = getNullForVariable(addr);
2434 EmitARCStoreStrongCall(addr, null, /*ignored*/ true);
2435 return;
2436 }
2437
2438 llvm::Value *value = Builder.CreateLoad(addr);
2439 EmitARCRelease(value, precise);
2440}
2441
2442/// Store into a strong object. Always calls this:
2443/// call void \@objc_storeStrong(i8** %addr, i8* %value)
2444llvm::Value *CodeGenFunction::EmitARCStoreStrongCall(Address addr,
2445 llvm::Value *value,
2446 bool ignored) {
2447 assert(addr.getElementType() == value->getType())(static_cast <bool> (addr.getElementType() == value->
getType()) ? void (0) : __assert_fail ("addr.getElementType() == value->getType()"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 2447, __extension__ __PRETTY_FUNCTION__))
;
2448
2449 llvm::Function *&fn = CGM.getObjCEntrypoints().objc_storeStrong;
2450 if (!fn) {
2451 fn = CGM.getIntrinsic(llvm::Intrinsic::objc_storeStrong);
2452 setARCRuntimeFunctionLinkage(CGM, fn);
2453 }
2454
2455 llvm::Value *args[] = {
2456 Builder.CreateBitCast(addr.getPointer(), Int8PtrPtrTy),
2457 Builder.CreateBitCast(value, Int8PtrTy)
2458 };
2459 EmitNounwindRuntimeCall(fn, args);
2460
2461 if (ignored) return nullptr;
2462 return value;
2463}
2464
2465/// Store into a strong object. Sometimes calls this:
2466/// call void \@objc_storeStrong(i8** %addr, i8* %value)
2467/// Other times, breaks it down into components.
2468llvm::Value *CodeGenFunction::EmitARCStoreStrong(LValue dst,
2469 llvm::Value *newValue,
2470 bool ignored) {
2471 QualType type = dst.getType();
2472 bool isBlock = type->isBlockPointerType();
2473
2474 // Use a store barrier at -O0 unless this is a block type or the
2475 // lvalue is inadequately aligned.
2476 if (shouldUseFusedARCCalls() &&
2477 !isBlock &&
2478 (dst.getAlignment().isZero() ||
2479 dst.getAlignment() >= CharUnits::fromQuantity(PointerAlignInBytes))) {
2480 return EmitARCStoreStrongCall(dst.getAddress(*this), newValue, ignored);
2481 }
2482
2483 // Otherwise, split it out.
2484
2485 // Retain the new value.
2486 newValue = EmitARCRetain(type, newValue);
2487
2488 // Read the old value.
2489 llvm::Value *oldValue = EmitLoadOfScalar(dst, SourceLocation());
2490
2491 // Store. We do this before the release so that any deallocs won't
2492 // see the old value.
2493 EmitStoreOfScalar(newValue, dst);
2494
2495 // Finally, release the old value.
2496 EmitARCRelease(oldValue, dst.isARCPreciseLifetime());
2497
2498 return newValue;
2499}
2500
2501/// Autorelease the given object.
2502/// call i8* \@objc_autorelease(i8* %value)
2503llvm::Value *CodeGenFunction::EmitARCAutorelease(llvm::Value *value) {
2504 return emitARCValueOperation(*this, value, nullptr,
2505 CGM.getObjCEntrypoints().objc_autorelease,
2506 llvm::Intrinsic::objc_autorelease);
2507}
2508
2509/// Autorelease the given object.
2510/// call i8* \@objc_autoreleaseReturnValue(i8* %value)
2511llvm::Value *
2512CodeGenFunction::EmitARCAutoreleaseReturnValue(llvm::Value *value) {
2513 return emitARCValueOperation(*this, value, nullptr,
2514 CGM.getObjCEntrypoints().objc_autoreleaseReturnValue,
2515 llvm::Intrinsic::objc_autoreleaseReturnValue,
2516 llvm::CallInst::TCK_Tail);
2517}
2518
2519/// Do a fused retain/autorelease of the given object.
2520/// call i8* \@objc_retainAutoreleaseReturnValue(i8* %value)
2521llvm::Value *
2522CodeGenFunction::EmitARCRetainAutoreleaseReturnValue(llvm::Value *value) {
2523 return emitARCValueOperation(*this, value, nullptr,
2524 CGM.getObjCEntrypoints().objc_retainAutoreleaseReturnValue,
2525 llvm::Intrinsic::objc_retainAutoreleaseReturnValue,
2526 llvm::CallInst::TCK_Tail);
2527}
2528
2529/// Do a fused retain/autorelease of the given object.
2530/// call i8* \@objc_retainAutorelease(i8* %value)
2531/// or
2532/// %retain = call i8* \@objc_retainBlock(i8* %value)
2533/// call i8* \@objc_autorelease(i8* %retain)
2534llvm::Value *CodeGenFunction::EmitARCRetainAutorelease(QualType type,
2535 llvm::Value *value) {
2536 if (!type->isBlockPointerType())
2537 return EmitARCRetainAutoreleaseNonBlock(value);
2538
2539 if (isa<llvm::ConstantPointerNull>(value)) return value;
2540
2541 llvm::Type *origType = value->getType();
2542 value = Builder.CreateBitCast(value, Int8PtrTy);
2543 value = EmitARCRetainBlock(value, /*mandatory*/ true);
2544 value = EmitARCAutorelease(value);
2545 return Builder.CreateBitCast(value, origType);
2546}
2547
2548/// Do a fused retain/autorelease of the given object.
2549/// call i8* \@objc_retainAutorelease(i8* %value)
2550llvm::Value *
2551CodeGenFunction::EmitARCRetainAutoreleaseNonBlock(llvm::Value *value) {
2552 return emitARCValueOperation(*this, value, nullptr,
2553 CGM.getObjCEntrypoints().objc_retainAutorelease,
2554 llvm::Intrinsic::objc_retainAutorelease);
2555}
2556
2557/// i8* \@objc_loadWeak(i8** %addr)
2558/// Essentially objc_autorelease(objc_loadWeakRetained(addr)).
2559llvm::Value *CodeGenFunction::EmitARCLoadWeak(Address addr) {
2560 return emitARCLoadOperation(*this, addr,
2561 CGM.getObjCEntrypoints().objc_loadWeak,
2562 llvm::Intrinsic::objc_loadWeak);
2563}
2564
2565/// i8* \@objc_loadWeakRetained(i8** %addr)
2566llvm::Value *CodeGenFunction::EmitARCLoadWeakRetained(Address addr) {
2567 return emitARCLoadOperation(*this, addr,
2568 CGM.getObjCEntrypoints().objc_loadWeakRetained,
2569 llvm::Intrinsic::objc_loadWeakRetained);
2570}
2571
2572/// i8* \@objc_storeWeak(i8** %addr, i8* %value)
2573/// Returns %value.
2574llvm::Value *CodeGenFunction::EmitARCStoreWeak(Address addr,
2575 llvm::Value *value,
2576 bool ignored) {
2577 return emitARCStoreOperation(*this, addr, value,
2578 CGM.getObjCEntrypoints().objc_storeWeak,
2579 llvm::Intrinsic::objc_storeWeak, ignored);
2580}
2581
2582/// i8* \@objc_initWeak(i8** %addr, i8* %value)
2583/// Returns %value. %addr is known to not have a current weak entry.
2584/// Essentially equivalent to:
2585/// *addr = nil; objc_storeWeak(addr, value);
2586void CodeGenFunction::EmitARCInitWeak(Address addr, llvm::Value *value) {
2587 // If we're initializing to null, just write null to memory; no need
2588 // to get the runtime involved. But don't do this if optimization
2589 // is enabled, because accounting for this would make the optimizer
2590 // much more complicated.
2591 if (isa<llvm::ConstantPointerNull>(value) &&
2592 CGM.getCodeGenOpts().OptimizationLevel == 0) {
2593 Builder.CreateStore(value, addr);
2594 return;
2595 }
2596
2597 emitARCStoreOperation(*this, addr, value,
2598 CGM.getObjCEntrypoints().objc_initWeak,
2599 llvm::Intrinsic::objc_initWeak, /*ignored*/ true);
2600}
2601
2602/// void \@objc_destroyWeak(i8** %addr)
2603/// Essentially objc_storeWeak(addr, nil).
2604void CodeGenFunction::EmitARCDestroyWeak(Address addr) {
2605 llvm::Function *&fn = CGM.getObjCEntrypoints().objc_destroyWeak;
2606 if (!fn) {
2607 fn = CGM.getIntrinsic(llvm::Intrinsic::objc_destroyWeak);
2608 setARCRuntimeFunctionLinkage(CGM, fn);
2609 }
2610
2611 // Cast the argument to 'id*'.
2612 addr = Builder.CreateBitCast(addr, Int8PtrPtrTy);
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 = CGM.getIntrinsic(llvm::Intrinsic::objc_autoreleasePoolPush);
2656 setARCRuntimeFunctionLinkage(CGM, fn);
2657 }
2658
2659 return EmitNounwindRuntimeCall(fn);
2660}
2661
2662/// Produce the code to do a primitive release.
2663/// call void \@objc_autoreleasePoolPop(i8* %ptr)
2664void CodeGenFunction::EmitObjCAutoreleasePoolPop(llvm::Value *value) {
2665 assert(value->getType() == Int8PtrTy)(static_cast <bool> (value->getType() == Int8PtrTy) ?
void (0) : __assert_fail ("value->getType() == Int8PtrTy"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 2665, __extension__ __PRETTY_FUNCTION__))
;
2666
2667 if (getInvokeDest()) {
2668 // Call the runtime method not the intrinsic if we are handling exceptions
2669 llvm::FunctionCallee &fn =
2670 CGM.getObjCEntrypoints().objc_autoreleasePoolPopInvoke;
2671 if (!fn) {
2672 llvm::FunctionType *fnType =
2673 llvm::FunctionType::get(Builder.getVoidTy(), Int8PtrTy, false);
2674 fn = CGM.CreateRuntimeFunction(fnType, "objc_autoreleasePoolPop");
2675 setARCRuntimeFunctionLinkage(CGM, fn);
2676 }
2677
2678 // objc_autoreleasePoolPop can throw.
2679 EmitRuntimeCallOrInvoke(fn, value);
2680 } else {
2681 llvm::FunctionCallee &fn = CGM.getObjCEntrypoints().objc_autoreleasePoolPop;
2682 if (!fn) {
2683 fn = CGM.getIntrinsic(llvm::Intrinsic::objc_autoreleasePoolPop);
2684 setARCRuntimeFunctionLinkage(CGM, fn);
2685 }
2686
2687 EmitRuntimeCall(fn, value);
2688 }
2689}
2690
2691/// Produce the code to do an MRR version objc_autoreleasepool_push.
2692/// Which is: [[NSAutoreleasePool alloc] init];
2693/// Where alloc is declared as: + (id) alloc; in NSAutoreleasePool class.
2694/// init is declared as: - (id) init; in its NSObject super class.
2695///
2696llvm::Value *CodeGenFunction::EmitObjCMRRAutoreleasePoolPush() {
2697 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
2698 llvm::Value *Receiver = Runtime.EmitNSAutoreleasePoolClassRef(*this);
2699 // [NSAutoreleasePool alloc]
2700 IdentifierInfo *II = &CGM.getContext().Idents.get("alloc");
2701 Selector AllocSel = getContext().Selectors.getSelector(0, &II);
2702 CallArgList Args;
2703 RValue AllocRV =
2704 Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
2705 getContext().getObjCIdType(),
2706 AllocSel, Receiver, Args);
2707
2708 // [Receiver init]
2709 Receiver = AllocRV.getScalarVal();
2710 II = &CGM.getContext().Idents.get("init");
2711 Selector InitSel = getContext().Selectors.getSelector(0, &II);
2712 RValue InitRV =
2713 Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
2714 getContext().getObjCIdType(),
2715 InitSel, Receiver, Args);
2716 return InitRV.getScalarVal();
2717}
2718
2719/// Allocate the given objc object.
2720/// call i8* \@objc_alloc(i8* %value)
2721llvm::Value *CodeGenFunction::EmitObjCAlloc(llvm::Value *value,
2722 llvm::Type *resultType) {
2723 return emitObjCValueOperation(*this, value, resultType,
2724 CGM.getObjCEntrypoints().objc_alloc,
2725 "objc_alloc");
2726}
2727
2728/// Allocate the given objc object.
2729/// call i8* \@objc_allocWithZone(i8* %value)
2730llvm::Value *CodeGenFunction::EmitObjCAllocWithZone(llvm::Value *value,
2731 llvm::Type *resultType) {
2732 return emitObjCValueOperation(*this, value, resultType,
2733 CGM.getObjCEntrypoints().objc_allocWithZone,
2734 "objc_allocWithZone");
2735}
2736
2737llvm::Value *CodeGenFunction::EmitObjCAllocInit(llvm::Value *value,
2738 llvm::Type *resultType) {
2739 return emitObjCValueOperation(*this, value, resultType,
2740 CGM.getObjCEntrypoints().objc_alloc_init,
2741 "objc_alloc_init");
2742}
2743
2744/// Produce the code to do a primitive release.
2745/// [tmp drain];
2746void CodeGenFunction::EmitObjCMRRAutoreleasePoolPop(llvm::Value *Arg) {
2747 IdentifierInfo *II = &CGM.getContext().Idents.get("drain");
2748 Selector DrainSel = getContext().Selectors.getSelector(0, &II);
2749 CallArgList Args;
2750 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
2751 getContext().VoidTy, DrainSel, Arg, Args);
2752}
2753
2754void CodeGenFunction::destroyARCStrongPrecise(CodeGenFunction &CGF,
2755 Address addr,
2756 QualType type) {
2757 CGF.EmitARCDestroyStrong(addr, ARCPreciseLifetime);
2758}
2759
2760void CodeGenFunction::destroyARCStrongImprecise(CodeGenFunction &CGF,
2761 Address addr,
2762 QualType type) {
2763 CGF.EmitARCDestroyStrong(addr, ARCImpreciseLifetime);
2764}
2765
2766void CodeGenFunction::destroyARCWeak(CodeGenFunction &CGF,
2767 Address addr,
2768 QualType type) {
2769 CGF.EmitARCDestroyWeak(addr);
2770}
2771
2772void CodeGenFunction::emitARCIntrinsicUse(CodeGenFunction &CGF, Address addr,
2773 QualType type) {
2774 llvm::Value *value = CGF.Builder.CreateLoad(addr);
2775 CGF.EmitARCIntrinsicUse(value);
2776}
2777
2778/// Autorelease the given object.
2779/// call i8* \@objc_autorelease(i8* %value)
2780llvm::Value *CodeGenFunction::EmitObjCAutorelease(llvm::Value *value,
2781 llvm::Type *returnType) {
2782 return emitObjCValueOperation(
2783 *this, value, returnType,
2784 CGM.getObjCEntrypoints().objc_autoreleaseRuntimeFunction,
2785 "objc_autorelease");
2786}
2787
2788/// Retain the given object, with normal retain semantics.
2789/// call i8* \@objc_retain(i8* %value)
2790llvm::Value *CodeGenFunction::EmitObjCRetainNonBlock(llvm::Value *value,
2791 llvm::Type *returnType) {
2792 return emitObjCValueOperation(
2793 *this, value, returnType,
2794 CGM.getObjCEntrypoints().objc_retainRuntimeFunction, "objc_retain");
2795}
2796
2797/// Release the given object.
2798/// call void \@objc_release(i8* %value)
2799void CodeGenFunction::EmitObjCRelease(llvm::Value *value,
2800 ARCPreciseLifetime_t precise) {
2801 if (isa<llvm::ConstantPointerNull>(value)) return;
2802
2803 llvm::FunctionCallee &fn =
2804 CGM.getObjCEntrypoints().objc_releaseRuntimeFunction;
2805 if (!fn) {
2806 llvm::FunctionType *fnType =
2807 llvm::FunctionType::get(Builder.getVoidTy(), Int8PtrTy, false);
2808 fn = CGM.CreateRuntimeFunction(fnType, "objc_release");
2809 setARCRuntimeFunctionLinkage(CGM, fn);
2810 // We have Native ARC, so set nonlazybind attribute for performance
2811 if (llvm::Function *f = dyn_cast<llvm::Function>(fn.getCallee()))
2812 f->addFnAttr(llvm::Attribute::NonLazyBind);
2813 }
2814
2815 // Cast the argument to 'id'.
2816 value = Builder.CreateBitCast(value, Int8PtrTy);
2817
2818 // Call objc_release.
2819 llvm::CallBase *call = EmitCallOrInvoke(fn, value);
2820
2821 if (precise == ARCImpreciseLifetime) {
2822 call->setMetadata("clang.imprecise_release",
2823 llvm::MDNode::get(Builder.getContext(), None));
2824 }
2825}
2826
2827namespace {
2828 struct CallObjCAutoreleasePoolObject final : EHScopeStack::Cleanup {
2829 llvm::Value *Token;
2830
2831 CallObjCAutoreleasePoolObject(llvm::Value *token) : Token(token) {}
2832
2833 void Emit(CodeGenFunction &CGF, Flags flags) override {
2834 CGF.EmitObjCAutoreleasePoolPop(Token);
2835 }
2836 };
2837 struct CallObjCMRRAutoreleasePoolObject final : EHScopeStack::Cleanup {
2838 llvm::Value *Token;
2839
2840 CallObjCMRRAutoreleasePoolObject(llvm::Value *token) : Token(token) {}
2841
2842 void Emit(CodeGenFunction &CGF, Flags flags) override {
2843 CGF.EmitObjCMRRAutoreleasePoolPop(Token);
2844 }
2845 };
2846}
2847
2848void CodeGenFunction::EmitObjCAutoreleasePoolCleanup(llvm::Value *Ptr) {
2849 if (CGM.getLangOpts().ObjCAutoRefCount)
2850 EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, Ptr);
2851 else
2852 EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, Ptr);
2853}
2854
2855static bool shouldRetainObjCLifetime(Qualifiers::ObjCLifetime lifetime) {
2856 switch (lifetime) {
2857 case Qualifiers::OCL_None:
2858 case Qualifiers::OCL_ExplicitNone:
2859 case Qualifiers::OCL_Strong:
2860 case Qualifiers::OCL_Autoreleasing:
2861 return true;
2862
2863 case Qualifiers::OCL_Weak:
2864 return false;
2865 }
2866
2867 llvm_unreachable("impossible lifetime!")::llvm::llvm_unreachable_internal("impossible lifetime!", "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 2867)
;
2868}
2869
2870static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF,
2871 LValue lvalue,
2872 QualType type) {
2873 llvm::Value *result;
2874 bool shouldRetain = shouldRetainObjCLifetime(type.getObjCLifetime());
2875 if (shouldRetain) {
2876 result = CGF.EmitLoadOfLValue(lvalue, SourceLocation()).getScalarVal();
2877 } else {
2878 assert(type.getObjCLifetime() == Qualifiers::OCL_Weak)(static_cast <bool> (type.getObjCLifetime() == Qualifiers
::OCL_Weak) ? void (0) : __assert_fail ("type.getObjCLifetime() == Qualifiers::OCL_Weak"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 2878, __extension__ __PRETTY_FUNCTION__))
;
2879 result = CGF.EmitARCLoadWeakRetained(lvalue.getAddress(CGF));
2880 }
2881 return TryEmitResult(result, !shouldRetain);
2882}
2883
2884static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF,
2885 const Expr *e) {
2886 e = e->IgnoreParens();
2887 QualType type = e->getType();
2888
2889 // If we're loading retained from a __strong xvalue, we can avoid
2890 // an extra retain/release pair by zeroing out the source of this
2891 // "move" operation.
2892 if (e->isXValue() &&
2893 !type.isConstQualified() &&
2894 type.getObjCLifetime() == Qualifiers::OCL_Strong) {
2895 // Emit the lvalue.
2896 LValue lv = CGF.EmitLValue(e);
2897
2898 // Load the object pointer.
2899 llvm::Value *result = CGF.EmitLoadOfLValue(lv,
2900 SourceLocation()).getScalarVal();
2901
2902 // Set the source pointer to NULL.
2903 CGF.EmitStoreOfScalar(getNullForVariable(lv.getAddress(CGF)), lv);
2904
2905 return TryEmitResult(result, true);
2906 }
2907
2908 // As a very special optimization, in ARC++, if the l-value is the
2909 // result of a non-volatile assignment, do a simple retain of the
2910 // result of the call to objc_storeWeak instead of reloading.
2911 if (CGF.getLangOpts().CPlusPlus &&
2912 !type.isVolatileQualified() &&
2913 type.getObjCLifetime() == Qualifiers::OCL_Weak &&
2914 isa<BinaryOperator>(e) &&
2915 cast<BinaryOperator>(e)->getOpcode() == BO_Assign)
2916 return TryEmitResult(CGF.EmitScalarExpr(e), false);
2917
2918 // Try to emit code for scalar constant instead of emitting LValue and
2919 // loading it because we are not guaranteed to have an l-value. One of such
2920 // cases is DeclRefExpr referencing non-odr-used constant-evaluated variable.
2921 if (const auto *decl_expr = dyn_cast<DeclRefExpr>(e)) {
2922 auto *DRE = const_cast<DeclRefExpr *>(decl_expr);
2923 if (CodeGenFunction::ConstantEmission constant = CGF.tryEmitAsConstant(DRE))
2924 return TryEmitResult(CGF.emitScalarConstant(constant, DRE),
2925 !shouldRetainObjCLifetime(type.getObjCLifetime()));
2926 }
2927
2928 return tryEmitARCRetainLoadOfScalar(CGF, CGF.EmitLValue(e), type);
2929}
2930
2931typedef llvm::function_ref<llvm::Value *(CodeGenFunction &CGF,
2932 llvm::Value *value)>
2933 ValueTransform;
2934
2935/// Insert code immediately after a call.
2936
2937// FIXME: We should find a way to emit the runtime call immediately
2938// after the call is emitted to eliminate the need for this function.
2939static llvm::Value *emitARCOperationAfterCall(CodeGenFunction &CGF,
2940 llvm::Value *value,
2941 ValueTransform doAfterCall,
2942 ValueTransform doFallback) {
2943 CGBuilderTy::InsertPoint ip = CGF.Builder.saveIP();
2944 auto *callBase = dyn_cast<llvm::CallBase>(value);
2945
2946 if (callBase && llvm::objcarc::hasAttachedCallOpBundle(callBase)) {
2947 // Fall back if the call base has operand bundle "clang.arc.attachedcall".
2948 value = doFallback(CGF, value);
2949 } else if (llvm::CallInst *call = dyn_cast<llvm::CallInst>(value)) {
2950 // Place the retain immediately following the call.
2951 CGF.Builder.SetInsertPoint(call->getParent(),
2952 ++llvm::BasicBlock::iterator(call));
2953 value = doAfterCall(CGF, value);
2954 } else if (llvm::InvokeInst *invoke = dyn_cast<llvm::InvokeInst>(value)) {
2955 // Place the retain at the beginning of the normal destination block.
2956 llvm::BasicBlock *BB = invoke->getNormalDest();
2957 CGF.Builder.SetInsertPoint(BB, BB->begin());
2958 value = doAfterCall(CGF, value);
2959
2960 // Bitcasts can arise because of related-result returns. Rewrite
2961 // the operand.
2962 } else if (llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(value)) {
2963 // Change the insert point to avoid emitting the fall-back call after the
2964 // bitcast.
2965 CGF.Builder.SetInsertPoint(bitcast->getParent(), bitcast->getIterator());
2966 llvm::Value *operand = bitcast->getOperand(0);
2967 operand = emitARCOperationAfterCall(CGF, operand, doAfterCall, doFallback);
2968 bitcast->setOperand(0, operand);
2969 value = bitcast;
2970 } else {
2971 auto *phi = dyn_cast<llvm::PHINode>(value);
2972 if (phi && phi->getNumIncomingValues() == 2 &&
2973 isa<llvm::ConstantPointerNull>(phi->getIncomingValue(1)) &&
2974 isa<llvm::CallBase>(phi->getIncomingValue(0))) {
2975 // Handle phi instructions that are generated when it's necessary to check
2976 // whether the receiver of a message is null.
2977 llvm::Value *inVal = phi->getIncomingValue(0);
2978 inVal = emitARCOperationAfterCall(CGF, inVal, doAfterCall, doFallback);
2979 phi->setIncomingValue(0, inVal);
2980 value = phi;
2981 } else {
2982 // Generic fall-back case.
2983 // Retain using the non-block variant: we never need to do a copy
2984 // of a block that's been returned to us.
2985 value = doFallback(CGF, value);
2986 }
2987 }
2988
2989 CGF.Builder.restoreIP(ip);
2990 return value;
2991}
2992
2993/// Given that the given expression is some sort of call (which does
2994/// not return retained), emit a retain following it.
2995static llvm::Value *emitARCRetainCallResult(CodeGenFunction &CGF,
2996 const Expr *e) {
2997 llvm::Value *value = CGF.EmitScalarExpr(e);
2998 return emitARCOperationAfterCall(CGF, value,
2999 [](CodeGenFunction &CGF, llvm::Value *value) {
3000 return CGF.EmitARCRetainAutoreleasedReturnValue(value);
3001 },
3002 [](CodeGenFunction &CGF, llvm::Value *value) {
3003 return CGF.EmitARCRetainNonBlock(value);
3004 });
3005}
3006
3007/// Given that the given expression is some sort of call (which does
3008/// not return retained), perform an unsafeClaim following it.
3009static llvm::Value *emitARCUnsafeClaimCallResult(CodeGenFunction &CGF,
3010 const Expr *e) {
3011 llvm::Value *value = CGF.EmitScalarExpr(e);
3012 return emitARCOperationAfterCall(CGF, value,
3013 [](CodeGenFunction &CGF, llvm::Value *value) {
3014 return CGF.EmitARCUnsafeClaimAutoreleasedReturnValue(value);
3015 },
3016 [](CodeGenFunction &CGF, llvm::Value *value) {
3017 return value;
3018 });
3019}
3020
3021llvm::Value *CodeGenFunction::EmitARCReclaimReturnedObject(const Expr *E,
3022 bool allowUnsafeClaim) {
3023 if (allowUnsafeClaim &&
3024 CGM.getLangOpts().ObjCRuntime.hasARCUnsafeClaimAutoreleasedReturnValue()) {
3025 return emitARCUnsafeClaimCallResult(*this, E);
3026 } else {
3027 llvm::Value *value = emitARCRetainCallResult(*this, E);
3028 return EmitObjCConsumeObject(E->getType(), value);
3029 }
3030}
3031
3032/// Determine whether it might be important to emit a separate
3033/// objc_retain_block on the result of the given expression, or
3034/// whether it's okay to just emit it in a +1 context.
3035static bool shouldEmitSeparateBlockRetain(const Expr *e) {
3036 assert(e->getType()->isBlockPointerType())(static_cast <bool> (e->getType()->isBlockPointerType
()) ? void (0) : __assert_fail ("e->getType()->isBlockPointerType()"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 3036, __extension__ __PRETTY_FUNCTION__))
;
3037 e = e->IgnoreParens();
3038
3039 // For future goodness, emit block expressions directly in +1
3040 // contexts if we can.
3041 if (isa<BlockExpr>(e))
3042 return false;
3043
3044 if (const CastExpr *cast = dyn_cast<CastExpr>(e)) {
3045 switch (cast->getCastKind()) {
3046 // Emitting these operations in +1 contexts is goodness.
3047 case CK_LValueToRValue:
3048 case CK_ARCReclaimReturnedObject:
3049 case CK_ARCConsumeObject:
3050 case CK_ARCProduceObject:
3051 return false;
3052
3053 // These operations preserve a block type.
3054 case CK_NoOp:
3055 case CK_BitCast:
3056 return shouldEmitSeparateBlockRetain(cast->getSubExpr());
3057
3058 // These operations are known to be bad (or haven't been considered).
3059 case CK_AnyPointerToBlockPointerCast:
3060 default:
3061 return true;
3062 }
3063 }
3064
3065 return true;
3066}
3067
3068namespace {
3069/// A CRTP base class for emitting expressions of retainable object
3070/// pointer type in ARC.
3071template <typename Impl, typename Result> class ARCExprEmitter {
3072protected:
3073 CodeGenFunction &CGF;
3074 Impl &asImpl() { return *static_cast<Impl*>(this); }
3075
3076 ARCExprEmitter(CodeGenFunction &CGF) : CGF(CGF) {}
3077
3078public:
3079 Result visit(const Expr *e);
3080 Result visitCastExpr(const CastExpr *e);
3081 Result visitPseudoObjectExpr(const PseudoObjectExpr *e);
3082 Result visitBlockExpr(const BlockExpr *e);
3083 Result visitBinaryOperator(const BinaryOperator *e);
3084 Result visitBinAssign(const BinaryOperator *e);
3085 Result visitBinAssignUnsafeUnretained(const BinaryOperator *e);
3086 Result visitBinAssignAutoreleasing(const BinaryOperator *e);
3087 Result visitBinAssignWeak(const BinaryOperator *e);
3088 Result visitBinAssignStrong(const BinaryOperator *e);
3089
3090 // Minimal implementation:
3091 // Result visitLValueToRValue(const Expr *e)
3092 // Result visitConsumeObject(const Expr *e)
3093 // Result visitExtendBlockObject(const Expr *e)
3094 // Result visitReclaimReturnedObject(const Expr *e)
3095 // Result visitCall(const Expr *e)
3096 // Result visitExpr(const Expr *e)
3097 //
3098 // Result emitBitCast(Result result, llvm::Type *resultType)
3099 // llvm::Value *getValueOfResult(Result result)
3100};
3101}
3102
3103/// Try to emit a PseudoObjectExpr under special ARC rules.
3104///
3105/// This massively duplicates emitPseudoObjectRValue.
3106template <typename Impl, typename Result>
3107Result
3108ARCExprEmitter<Impl,Result>::visitPseudoObjectExpr(const PseudoObjectExpr *E) {
3109 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
3110
3111 // Find the result expression.
3112 const Expr *resultExpr = E->getResultExpr();
3113 assert(resultExpr)(static_cast <bool> (resultExpr) ? void (0) : __assert_fail
("resultExpr", "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 3113, __extension__ __PRETTY_FUNCTION__))
;
18
Assuming 'resultExpr' is non-null
19
'?' condition is true
3114 Result result;
20
'result' declared without an initial value
3115
3116 for (PseudoObjectExpr::const_semantics_iterator
21
Loop condition is false. Execution continues on line 3152
3117 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
3118 const Expr *semantic = *i;
3119
3120 // If this semantic expression is an opaque value, bind it
3121 // to the result of its source expression.
3122 if (const OpaqueValueExpr *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
3123 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
3124 OVMA opaqueData;
3125
3126 // If this semantic is the result of the pseudo-object
3127 // expression, try to evaluate the source as +1.
3128 if (ov == resultExpr) {
3129 assert(!OVMA::shouldBindAsLValue(ov))(static_cast <bool> (!OVMA::shouldBindAsLValue(ov)) ? void
(0) : __assert_fail ("!OVMA::shouldBindAsLValue(ov)", "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 3129, __extension__ __PRETTY_FUNCTION__))
;
3130 result = asImpl().visit(ov->getSourceExpr());
3131 opaqueData = OVMA::bind(CGF, ov,
3132 RValue::get(asImpl().getValueOfResult(result)));
3133
3134 // Otherwise, just bind it.
3135 } else {
3136 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
3137 }
3138 opaques.push_back(opaqueData);
3139
3140 // Otherwise, if the expression is the result, evaluate it
3141 // and remember the result.
3142 } else if (semantic == resultExpr) {
3143 result = asImpl().visit(semantic);
3144
3145 // Otherwise, evaluate the expression in an ignored context.
3146 } else {
3147 CGF.EmitIgnoredExpr(semantic);
3148 }
3149 }
3150
3151 // Unbind all the opaques now.
3152 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 3155
3153 opaques[i].unbind(CGF);
3154
3155 return result;
24
Undefined or garbage value returned to caller
3156}
3157
3158template <typename Impl, typename Result>
3159Result ARCExprEmitter<Impl, Result>::visitBlockExpr(const BlockExpr *e) {
3160 // The default implementation just forwards the expression to visitExpr.
3161 return asImpl().visitExpr(e);
3162}
3163
3164template <typename Impl, typename Result>
3165Result ARCExprEmitter<Impl,Result>::visitCastExpr(const CastExpr *e) {
3166 switch (e->getCastKind()) {
3167
3168 // No-op casts don't change the type, so we just ignore them.
3169 case CK_NoOp:
3170 return asImpl().visit(e->getSubExpr());
3171
3172 // These casts can change the type.
3173 case CK_CPointerToObjCPointerCast:
3174 case CK_BlockPointerToObjCPointerCast:
3175 case CK_AnyPointerToBlockPointerCast:
3176 case CK_BitCast: {
3177 llvm::Type *resultType = CGF.ConvertType(e->getType());
3178 assert(e->getSubExpr()->getType()->hasPointerRepresentation())(static_cast <bool> (e->getSubExpr()->getType()->
hasPointerRepresentation()) ? void (0) : __assert_fail ("e->getSubExpr()->getType()->hasPointerRepresentation()"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 3178, __extension__ __PRETTY_FUNCTION__))
;
3179 Result result = asImpl().visit(e->getSubExpr());
3180 return asImpl().emitBitCast(result, resultType);
3181 }
3182
3183 // Handle some casts specially.
3184 case CK_LValueToRValue:
3185 return asImpl().visitLValueToRValue(e->getSubExpr());
3186 case CK_ARCConsumeObject:
3187 return asImpl().visitConsumeObject(e->getSubExpr());
3188 case CK_ARCExtendBlockObject:
3189 return asImpl().visitExtendBlockObject(e->getSubExpr());
3190 case CK_ARCReclaimReturnedObject:
3191 return asImpl().visitReclaimReturnedObject(e->getSubExpr());
3192
3193 // Otherwise, use the default logic.
3194 default:
3195 return asImpl().visitExpr(e);
3196 }
3197}
3198
3199template <typename Impl, typename Result>
3200Result
3201ARCExprEmitter<Impl,Result>::visitBinaryOperator(const BinaryOperator *e) {
3202 switch (e->getOpcode()) {
3203 case BO_Comma:
3204 CGF.EmitIgnoredExpr(e->getLHS());
3205 CGF.EnsureInsertPoint();
3206 return asImpl().visit(e->getRHS());
3207
3208 case BO_Assign:
3209 return asImpl().visitBinAssign(e);
3210
3211 default:
3212 return asImpl().visitExpr(e);
3213 }
3214}
3215
3216template <typename Impl, typename Result>
3217Result ARCExprEmitter<Impl,Result>::visitBinAssign(const BinaryOperator *e) {
3218 switch (e->getLHS()->getType().getObjCLifetime()) {
3219 case Qualifiers::OCL_ExplicitNone:
3220 return asImpl().visitBinAssignUnsafeUnretained(e);
3221
3222 case Qualifiers::OCL_Weak:
3223 return asImpl().visitBinAssignWeak(e);
3224
3225 case Qualifiers::OCL_Autoreleasing:
3226 return asImpl().visitBinAssignAutoreleasing(e);
3227
3228 case Qualifiers::OCL_Strong:
3229 return asImpl().visitBinAssignStrong(e);
3230
3231 case Qualifiers::OCL_None:
3232 return asImpl().visitExpr(e);
3233 }
3234 llvm_unreachable("bad ObjC ownership qualifier")::llvm::llvm_unreachable_internal("bad ObjC ownership qualifier"
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 3234)
;
3235}
3236
3237/// The default rule for __unsafe_unretained emits the RHS recursively,
3238/// stores into the unsafe variable, and propagates the result outward.
3239template <typename Impl, typename Result>
3240Result ARCExprEmitter<Impl,Result>::
3241 visitBinAssignUnsafeUnretained(const BinaryOperator *e) {
3242 // Recursively emit the RHS.
3243 // For __block safety, do this before emitting the LHS.
3244 Result result = asImpl().visit(e->getRHS());
3245
3246 // Perform the store.
3247 LValue lvalue =
3248 CGF.EmitCheckedLValue(e->getLHS(), CodeGenFunction::TCK_Store);
3249 CGF.EmitStoreThroughLValue(RValue::get(asImpl().getValueOfResult(result)),
3250 lvalue);
3251
3252 return result;
3253}
3254
3255template <typename Impl, typename Result>
3256Result
3257ARCExprEmitter<Impl,Result>::visitBinAssignAutoreleasing(const BinaryOperator *e) {
3258 return asImpl().visitExpr(e);
3259}
3260
3261template <typename Impl, typename Result>
3262Result
3263ARCExprEmitter<Impl,Result>::visitBinAssignWeak(const BinaryOperator *e) {
3264 return asImpl().visitExpr(e);
3265}
3266
3267template <typename Impl, typename Result>
3268Result
3269ARCExprEmitter<Impl,Result>::visitBinAssignStrong(const BinaryOperator *e) {
3270 return asImpl().visitExpr(e);
3271}
3272
3273/// The general expression-emission logic.
3274template <typename Impl, typename Result>
3275Result ARCExprEmitter<Impl,Result>::visit(const Expr *e) {
3276 // We should *never* see a nested full-expression here, because if
3277 // we fail to emit at +1, our caller must not retain after we close
3278 // out the full-expression. This isn't as important in the unsafe
3279 // emitter.
3280 assert(!isa<ExprWithCleanups>(e))(static_cast <bool> (!isa<ExprWithCleanups>(e)) ?
void (0) : __assert_fail ("!isa<ExprWithCleanups>(e)",
"/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 3280, __extension__ __PRETTY_FUNCTION__))
;
8
'e' is not a 'ExprWithCleanups'
9
'?' condition is true
3281
3282 // Look through parens, __extension__, generic selection, etc.
3283 e = e->IgnoreParens();
3284
3285 // Handle certain kinds of casts.
3286 if (const CastExpr *ce
10.1
'ce' is null
= dyn_cast<CastExpr>(e)) {
10
Assuming 'e' is not a 'CastExpr'
11
Taking false branch
3287 return asImpl().visitCastExpr(ce);
3288
3289 // Handle the comma operator.
3290 } else if (auto op
12.1
'op' is null
= dyn_cast<BinaryOperator>(e)) {
12
Assuming 'e' is not a 'BinaryOperator'
3291 return asImpl().visitBinaryOperator(op);
3292
3293 // TODO: handle conditional operators here
3294
3295 // For calls and message sends, use the retained-call logic.
3296 // Delegate inits are a special case in that they're the only
3297 // returns-retained expression that *isn't* surrounded by
3298 // a consume.
3299 } else if (isa<CallExpr>(e) ||
13
Assuming 'e' is not a 'CallExpr'
3300 (isa<ObjCMessageExpr>(e) &&
14
Assuming 'e' is not a 'ObjCMessageExpr'
3301 !cast<ObjCMessageExpr>(e)->isDelegateInitCall())) {
3302 return asImpl().visitCall(e);
3303
3304 // Look through pseudo-object expressions.
3305 } else if (const PseudoObjectExpr *pseudo
15.1
'pseudo' is non-null
= dyn_cast<PseudoObjectExpr>(e)) {
15
Assuming 'e' is a 'PseudoObjectExpr'
16
Taking true branch
3306 return asImpl().visitPseudoObjectExpr(pseudo);
17
Calling 'ARCExprEmitter::visitPseudoObjectExpr'
3307 } else if (auto *be = dyn_cast<BlockExpr>(e))
3308 return asImpl().visitBlockExpr(be);
3309
3310 return asImpl().visitExpr(e);
3311}
3312
3313namespace {
3314
3315/// An emitter for +1 results.
3316struct ARCRetainExprEmitter :
3317 public ARCExprEmitter<ARCRetainExprEmitter, TryEmitResult> {
3318
3319 ARCRetainExprEmitter(CodeGenFunction &CGF) : ARCExprEmitter(CGF) {}
3320
3321 llvm::Value *getValueOfResult(TryEmitResult result) {
3322 return result.getPointer();
3323 }
3324
3325 TryEmitResult emitBitCast(TryEmitResult result, llvm::Type *resultType) {
3326 llvm::Value *value = result.getPointer();
3327 value = CGF.Builder.CreateBitCast(value, resultType);
3328 result.setPointer(value);
3329 return result;
3330 }
3331
3332 TryEmitResult visitLValueToRValue(const Expr *e) {
3333 return tryEmitARCRetainLoadOfScalar(CGF, e);
3334 }
3335
3336 /// For consumptions, just emit the subexpression and thus elide
3337 /// the retain/release pair.
3338 TryEmitResult visitConsumeObject(const Expr *e) {
3339 llvm::Value *result = CGF.EmitScalarExpr(e);
3340 return TryEmitResult(result, true);
3341 }
3342
3343 TryEmitResult visitBlockExpr(const BlockExpr *e) {
3344 TryEmitResult result = visitExpr(e);
3345 // Avoid the block-retain if this is a block literal that doesn't need to be
3346 // copied to the heap.
3347 if (e->getBlockDecl()->canAvoidCopyToHeap())
3348 result.setInt(true);
3349 return result;
3350 }
3351
3352 /// Block extends are net +0. Naively, we could just recurse on
3353 /// the subexpression, but actually we need to ensure that the
3354 /// value is copied as a block, so there's a little filter here.
3355 TryEmitResult visitExtendBlockObject(const Expr *e) {
3356 llvm::Value *result; // will be a +0 value
3357
3358 // If we can't safely assume the sub-expression will produce a
3359 // block-copied value, emit the sub-expression at +0.
3360 if (shouldEmitSeparateBlockRetain(e)) {
3361 result = CGF.EmitScalarExpr(e);
3362
3363 // Otherwise, try to emit the sub-expression at +1 recursively.
3364 } else {
3365 TryEmitResult subresult = asImpl().visit(e);
3366
3367 // If that produced a retained value, just use that.
3368 if (subresult.getInt()) {
3369 return subresult;
3370 }
3371
3372 // Otherwise it's +0.
3373 result = subresult.getPointer();
3374 }
3375
3376 // Retain the object as a block.
3377 result = CGF.EmitARCRetainBlock(result, /*mandatory*/ true);
3378 return TryEmitResult(result, true);
3379 }
3380
3381 /// For reclaims, emit the subexpression as a retained call and
3382 /// skip the consumption.
3383 TryEmitResult visitReclaimReturnedObject(const Expr *e) {
3384 llvm::Value *result = emitARCRetainCallResult(CGF, e);
3385 return TryEmitResult(result, true);
3386 }
3387
3388 /// When we have an undecorated call, retroactively do a claim.
3389 TryEmitResult visitCall(const Expr *e) {
3390 llvm::Value *result = emitARCRetainCallResult(CGF, e);
3391 return TryEmitResult(result, true);
3392 }
3393
3394 // TODO: maybe special-case visitBinAssignWeak?
3395
3396 TryEmitResult visitExpr(const Expr *e) {
3397 // We didn't find an obvious production, so emit what we've got and
3398 // tell the caller that we didn't manage to retain.
3399 llvm::Value *result = CGF.EmitScalarExpr(e);
3400 return TryEmitResult(result, false);
3401 }
3402};
3403}
3404
3405static TryEmitResult
3406tryEmitARCRetainScalarExpr(CodeGenFunction &CGF, const Expr *e) {
3407 return ARCRetainExprEmitter(CGF).visit(e);
3408}
3409
3410static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF,
3411 LValue lvalue,
3412 QualType type) {
3413 TryEmitResult result = tryEmitARCRetainLoadOfScalar(CGF, lvalue, type);
3414 llvm::Value *value = result.getPointer();
3415 if (!result.getInt())
3416 value = CGF.EmitARCRetain(type, value);
3417 return value;
3418}
3419
3420/// EmitARCRetainScalarExpr - Semantically equivalent to
3421/// EmitARCRetainObject(e->getType(), EmitScalarExpr(e)), but making a
3422/// best-effort attempt to peephole expressions that naturally produce
3423/// retained objects.
3424llvm::Value *CodeGenFunction::EmitARCRetainScalarExpr(const Expr *e) {
3425 // The retain needs to happen within the full-expression.
3426 if (const ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(e)) {
3427 RunCleanupsScope scope(*this);
3428 return EmitARCRetainScalarExpr(cleanups->getSubExpr());
3429 }
3430
3431 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e);
3432 llvm::Value *value = result.getPointer();
3433 if (!result.getInt())
3434 value = EmitARCRetain(e->getType(), value);
3435 return value;
3436}
3437
3438llvm::Value *
3439CodeGenFunction::EmitARCRetainAutoreleaseScalarExpr(const Expr *e) {
3440 // The retain needs to happen within the full-expression.
3441 if (const ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(e)) {
3442 RunCleanupsScope scope(*this);
3443 return EmitARCRetainAutoreleaseScalarExpr(cleanups->getSubExpr());
3444 }
3445
3446 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e);
3447 llvm::Value *value = result.getPointer();
3448 if (result.getInt())
3449 value = EmitARCAutorelease(value);
3450 else
3451 value = EmitARCRetainAutorelease(e->getType(), value);
3452 return value;
3453}
3454
3455llvm::Value *CodeGenFunction::EmitARCExtendBlockObject(const Expr *e) {
3456 llvm::Value *result;
3457 bool doRetain;
3458
3459 if (shouldEmitSeparateBlockRetain(e)) {
3460 result = EmitScalarExpr(e);
3461 doRetain = true;
3462 } else {
3463 TryEmitResult subresult = tryEmitARCRetainScalarExpr(*this, e);
3464 result = subresult.getPointer();
3465 doRetain = !subresult.getInt();
3466 }
3467
3468 if (doRetain)
3469 result = EmitARCRetainBlock(result, /*mandatory*/ true);
3470 return EmitObjCConsumeObject(e->getType(), result);
3471}
3472
3473llvm::Value *CodeGenFunction::EmitObjCThrowOperand(const Expr *expr) {
3474 // In ARC, retain and autorelease the expression.
3475 if (getLangOpts().ObjCAutoRefCount) {
3476 // Do so before running any cleanups for the full-expression.
3477 // EmitARCRetainAutoreleaseScalarExpr does this for us.
3478 return EmitARCRetainAutoreleaseScalarExpr(expr);
3479 }
3480
3481 // Otherwise, use the normal scalar-expression emission. The
3482 // exception machinery doesn't do anything special with the
3483 // exception like retaining it, so there's no safety associated with
3484 // only running cleanups after the throw has started, and when it
3485 // matters it tends to be substantially inferior code.
3486 return EmitScalarExpr(expr);
3487}
3488
3489namespace {
3490
3491/// An emitter for assigning into an __unsafe_unretained context.
3492struct ARCUnsafeUnretainedExprEmitter :
3493 public ARCExprEmitter<ARCUnsafeUnretainedExprEmitter, llvm::Value*> {
3494
3495 ARCUnsafeUnretainedExprEmitter(CodeGenFunction &CGF) : ARCExprEmitter(CGF) {}
3496
3497 llvm::Value *getValueOfResult(llvm::Value *value) {
3498 return value;
3499 }
3500
3501 llvm::Value *emitBitCast(llvm::Value *value, llvm::Type *resultType) {
3502 return CGF.Builder.CreateBitCast(value, resultType);
3503 }
3504
3505 llvm::Value *visitLValueToRValue(const Expr *e) {
3506 return CGF.EmitScalarExpr(e);
3507 }
3508
3509 /// For consumptions, just emit the subexpression and perform the
3510 /// consumption like normal.
3511 llvm::Value *visitConsumeObject(const Expr *e) {
3512 llvm::Value *value = CGF.EmitScalarExpr(e);
3513 return CGF.EmitObjCConsumeObject(e->getType(), value);
3514 }
3515
3516 /// No special logic for block extensions. (This probably can't
3517 /// actually happen in this emitter, though.)
3518 llvm::Value *visitExtendBlockObject(const Expr *e) {
3519 return CGF.EmitARCExtendBlockObject(e);
3520 }
3521
3522 /// For reclaims, perform an unsafeClaim if that's enabled.
3523 llvm::Value *visitReclaimReturnedObject(const Expr *e) {
3524 return CGF.EmitARCReclaimReturnedObject(e, /*unsafe*/ true);
3525 }
3526
3527 /// When we have an undecorated call, just emit it without adding
3528 /// the unsafeClaim.
3529 llvm::Value *visitCall(const Expr *e) {
3530 return CGF.EmitScalarExpr(e);
3531 }
3532
3533 /// Just do normal scalar emission in the default case.
3534 llvm::Value *visitExpr(const Expr *e) {
3535 return CGF.EmitScalarExpr(e);
3536 }
3537};
3538}
3539
3540static llvm::Value *emitARCUnsafeUnretainedScalarExpr(CodeGenFunction &CGF,
3541 const Expr *e) {
3542 return ARCUnsafeUnretainedExprEmitter(CGF).visit(e);
7
Calling 'ARCExprEmitter::visit'
3543}
3544
3545/// EmitARCUnsafeUnretainedScalarExpr - Semantically equivalent to
3546/// immediately releasing the resut of EmitARCRetainScalarExpr, but
3547/// avoiding any spurious retains, including by performing reclaims
3548/// with objc_unsafeClaimAutoreleasedReturnValue.
3549llvm::Value *CodeGenFunction::EmitARCUnsafeUnretainedScalarExpr(const Expr *e) {
3550 // Look through full-expressions.
3551 if (const ExprWithCleanups *cleanups
4.1
'cleanups' is null
= dyn_cast<ExprWithCleanups>(e)) {
4
Assuming 'e' is not a 'ExprWithCleanups'
5
Taking false branch
3552 RunCleanupsScope scope(*this);
3553 return emitARCUnsafeUnretainedScalarExpr(*this, cleanups->getSubExpr());
3554 }
3555
3556 return emitARCUnsafeUnretainedScalarExpr(*this, e);
6
Calling 'emitARCUnsafeUnretainedScalarExpr'
3557}
3558
3559std::pair<LValue,llvm::Value*>
3560CodeGenFunction::EmitARCStoreUnsafeUnretained(const BinaryOperator *e,
3561 bool ignored) {
3562 // Evaluate the RHS first. If we're ignoring the result, assume
3563 // that we can emit at an unsafe +0.
3564 llvm::Value *value;
3565 if (ignored) {
1
Assuming 'ignored' is true
2
Taking true branch
3566 value = EmitARCUnsafeUnretainedScalarExpr(e->getRHS());
3
Calling 'CodeGenFunction::EmitARCUnsafeUnretainedScalarExpr'
3567 } else {
3568 value = EmitScalarExpr(e->getRHS());
3569 }
3570
3571 // Emit the LHS and perform the store.
3572 LValue lvalue = EmitLValue(e->getLHS());
3573 EmitStoreOfScalar(value, lvalue);
3574
3575 return std::pair<LValue,llvm::Value*>(std::move(lvalue), value);
3576}
3577
3578std::pair<LValue,llvm::Value*>
3579CodeGenFunction::EmitARCStoreStrong(const BinaryOperator *e,
3580 bool ignored) {
3581 // Evaluate the RHS first.
3582 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e->getRHS());
3583 llvm::Value *value = result.getPointer();
3584
3585 bool hasImmediateRetain = result.getInt();
3586
3587 // If we didn't emit a retained object, and the l-value is of block
3588 // type, then we need to emit the block-retain immediately in case
3589 // it invalidates the l-value.
3590 if (!hasImmediateRetain && e->getType()->isBlockPointerType()) {
3591 value = EmitARCRetainBlock(value, /*mandatory*/ false);
3592 hasImmediateRetain = true;
3593 }
3594
3595 LValue lvalue = EmitLValue(e->getLHS());
3596
3597 // If the RHS was emitted retained, expand this.
3598 if (hasImmediateRetain) {
3599 llvm::Value *oldValue = EmitLoadOfScalar(lvalue, SourceLocation());
3600 EmitStoreOfScalar(value, lvalue);
3601 EmitARCRelease(oldValue, lvalue.isARCPreciseLifetime());
3602 } else {
3603 value = EmitARCStoreStrong(lvalue, value, ignored);
3604 }
3605
3606 return std::pair<LValue,llvm::Value*>(lvalue, value);
3607}
3608
3609std::pair<LValue,llvm::Value*>
3610CodeGenFunction::EmitARCStoreAutoreleasing(const BinaryOperator *e) {
3611 llvm::Value *value = EmitARCRetainAutoreleaseScalarExpr(e->getRHS());
3612 LValue lvalue = EmitLValue(e->getLHS());
3613
3614 EmitStoreOfScalar(value, lvalue);
3615
3616 return std::pair<LValue,llvm::Value*>(lvalue, value);
3617}
3618
3619void CodeGenFunction::EmitObjCAutoreleasePoolStmt(
3620 const ObjCAutoreleasePoolStmt &ARPS) {
3621 const Stmt *subStmt = ARPS.getSubStmt();
3622 const CompoundStmt &S = cast<CompoundStmt>(*subStmt);
3623
3624 CGDebugInfo *DI = getDebugInfo();
3625 if (DI)
3626 DI->EmitLexicalBlockStart(Builder, S.getLBracLoc());
3627
3628 // Keep track of the current cleanup stack depth.
3629 RunCleanupsScope Scope(*this);
3630 if (CGM.getLangOpts().ObjCRuntime.hasNativeARC()) {
3631 llvm::Value *token = EmitObjCAutoreleasePoolPush();
3632 EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, token);
3633 } else {
3634 llvm::Value *token = EmitObjCMRRAutoreleasePoolPush();
3635 EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, token);
3636 }
3637
3638 for (const auto *I : S.body())
3639 EmitStmt(I);
3640
3641 if (DI)
3642 DI->EmitLexicalBlockEnd(Builder, S.getRBracLoc());
3643}
3644
3645/// EmitExtendGCLifetime - Given a pointer to an Objective-C object,
3646/// make sure it survives garbage collection until this point.
3647void CodeGenFunction::EmitExtendGCLifetime(llvm::Value *object) {
3648 // We just use an inline assembly.
3649 llvm::FunctionType *extenderType
3650 = llvm::FunctionType::get(VoidTy, VoidPtrTy, RequiredArgs::All);
3651 llvm::InlineAsm *extender = llvm::InlineAsm::get(extenderType,
3652 /* assembly */ "",
3653 /* constraints */ "r",
3654 /* side effects */ true);
3655
3656 object = Builder.CreateBitCast(object, VoidPtrTy);
3657 EmitNounwindRuntimeCall(extender, object);
3658}
3659
3660/// GenerateObjCAtomicSetterCopyHelperFunction - Given a c++ object type with
3661/// non-trivial copy assignment function, produce following helper function.
3662/// static void copyHelper(Ty *dest, const Ty *source) { *dest = *source; }
3663///
3664llvm::Constant *
3665CodeGenFunction::GenerateObjCAtomicSetterCopyHelperFunction(
3666 const ObjCPropertyImplDecl *PID) {
3667 if (!getLangOpts().CPlusPlus ||
3668 !getLangOpts().ObjCRuntime.hasAtomicCopyHelper())
3669 return nullptr;
3670 QualType Ty = PID->getPropertyIvarDecl()->getType();
3671 if (!Ty->isRecordType())
3672 return nullptr;
3673 const ObjCPropertyDecl *PD = PID->getPropertyDecl();
3674 if ((!(PD->getPropertyAttributes() & ObjCPropertyAttribute::kind_atomic)))
3675 return nullptr;
3676 llvm::Constant *HelperFn = nullptr;
3677 if (hasTrivialSetExpr(PID))
3678 return nullptr;
3679 assert(PID->getSetterCXXAssignment() && "SetterCXXAssignment - null")(static_cast <bool> (PID->getSetterCXXAssignment() &&
"SetterCXXAssignment - null") ? void (0) : __assert_fail ("PID->getSetterCXXAssignment() && \"SetterCXXAssignment - null\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 3679, __extension__ __PRETTY_FUNCTION__))
;
3680 if ((HelperFn = CGM.getAtomicSetterHelperFnMap(Ty)))
3681 return HelperFn;
3682
3683 ASTContext &C = getContext();
3684 IdentifierInfo *II
3685 = &CGM.getContext().Idents.get("__assign_helper_atomic_property_");
3686
3687 QualType ReturnTy = C.VoidTy;
3688 QualType DestTy = C.getPointerType(Ty);
3689 QualType SrcTy = Ty;
3690 SrcTy.addConst();
3691 SrcTy = C.getPointerType(SrcTy);
3692
3693 SmallVector<QualType, 2> ArgTys;
3694 ArgTys.push_back(DestTy);
3695 ArgTys.push_back(SrcTy);
3696 QualType FunctionTy = C.getFunctionType(ReturnTy, ArgTys, {});
3697
3698 FunctionDecl *FD = FunctionDecl::Create(
3699 C, C.getTranslationUnitDecl(), SourceLocation(), SourceLocation(), II,
3700 FunctionTy, nullptr, SC_Static, false, false, false);
3701
3702 FunctionArgList args;
3703 ParmVarDecl *Params[2];
3704 ParmVarDecl *DstDecl = ParmVarDecl::Create(
3705 C, FD, SourceLocation(), SourceLocation(), nullptr, DestTy,
3706 C.getTrivialTypeSourceInfo(DestTy, SourceLocation()), SC_None,
3707 /*DefArg=*/nullptr);
3708 args.push_back(Params[0] = DstDecl);
3709 ParmVarDecl *SrcDecl = ParmVarDecl::Create(
3710 C, FD, SourceLocation(), SourceLocation(), nullptr, SrcTy,
3711 C.getTrivialTypeSourceInfo(SrcTy, SourceLocation()), SC_None,
3712 /*DefArg=*/nullptr);
3713 args.push_back(Params[1] = SrcDecl);
3714 FD->setParams(Params);
3715
3716 const CGFunctionInfo &FI =
3717 CGM.getTypes().arrangeBuiltinFunctionDeclaration(ReturnTy, args);
3718
3719 llvm::FunctionType *LTy = CGM.getTypes().GetFunctionType(FI);
3720
3721 llvm::Function *Fn =
3722 llvm::Function::Create(LTy, llvm::GlobalValue::InternalLinkage,
3723 "__assign_helper_atomic_property_",
3724 &CGM.getModule());
3725
3726 CGM.SetInternalFunctionAttributes(GlobalDecl(), Fn, FI);
3727
3728 StartFunction(FD, ReturnTy, Fn, FI, args);
3729
3730 DeclRefExpr DstExpr(C, DstDecl, false, DestTy, VK_PRValue, SourceLocation());
3731 UnaryOperator *DST = UnaryOperator::Create(
3732 C, &DstExpr, UO_Deref, DestTy->getPointeeType(), VK_LValue, OK_Ordinary,
3733 SourceLocation(), false, FPOptionsOverride());
3734
3735 DeclRefExpr SrcExpr(C, SrcDecl, false, SrcTy, VK_PRValue, SourceLocation());
3736 UnaryOperator *SRC = UnaryOperator::Create(
3737 C, &SrcExpr, UO_Deref, SrcTy->getPointeeType(), VK_LValue, OK_Ordinary,
3738 SourceLocation(), false, FPOptionsOverride());
3739
3740 Expr *Args[2] = {DST, SRC};
3741 CallExpr *CalleeExp = cast<CallExpr>(PID->getSetterCXXAssignment());
3742 CXXOperatorCallExpr *TheCall = CXXOperatorCallExpr::Create(
3743 C, OO_Equal, CalleeExp->getCallee(), Args, DestTy->getPointeeType(),
3744 VK_LValue, SourceLocation(), FPOptionsOverride());
3745
3746 EmitStmt(TheCall);
3747
3748 FinishFunction();
3749 HelperFn = llvm::ConstantExpr::getBitCast(Fn, VoidPtrTy);
3750 CGM.setAtomicSetterHelperFnMap(Ty, HelperFn);
3751 return HelperFn;
3752}
3753
3754llvm::Constant *
3755CodeGenFunction::GenerateObjCAtomicGetterCopyHelperFunction(
3756 const ObjCPropertyImplDecl *PID) {
3757 if (!getLangOpts().CPlusPlus ||
3758 !getLangOpts().ObjCRuntime.hasAtomicCopyHelper())
3759 return nullptr;
3760 const ObjCPropertyDecl *PD = PID->getPropertyDecl();
3761 QualType Ty = PD->getType();
3762 if (!Ty->isRecordType())
3763 return nullptr;
3764 if ((!(PD->getPropertyAttributes() & ObjCPropertyAttribute::kind_atomic)))
3765 return nullptr;
3766 llvm::Constant *HelperFn = nullptr;
3767 if (hasTrivialGetExpr(PID))
3768 return nullptr;
3769 assert(PID->getGetterCXXConstructor() && "getGetterCXXConstructor - null")(static_cast <bool> (PID->getGetterCXXConstructor() &&
"getGetterCXXConstructor - null") ? void (0) : __assert_fail
("PID->getGetterCXXConstructor() && \"getGetterCXXConstructor - null\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 3769, __extension__ __PRETTY_FUNCTION__))
;
3770 if ((HelperFn = CGM.getAtomicGetterHelperFnMap(Ty)))
3771 return HelperFn;
3772
3773 ASTContext &C = getContext();
3774 IdentifierInfo *II =
3775 &CGM.getContext().Idents.get("__copy_helper_atomic_property_");
3776
3777 QualType ReturnTy = C.VoidTy;
3778 QualType DestTy = C.getPointerType(Ty);
3779 QualType SrcTy = Ty;
3780 SrcTy.addConst();
3781 SrcTy = C.getPointerType(SrcTy);
3782
3783 SmallVector<QualType, 2> ArgTys;
3784 ArgTys.push_back(DestTy);
3785 ArgTys.push_back(SrcTy);
3786 QualType FunctionTy = C.getFunctionType(ReturnTy, ArgTys, {});
3787
3788 FunctionDecl *FD = FunctionDecl::Create(
3789 C, C.getTranslationUnitDecl(), SourceLocation(), SourceLocation(), II,
3790 FunctionTy, nullptr, SC_Static, false, false, false);
3791
3792 FunctionArgList args;
3793 ParmVarDecl *Params[2];
3794 ParmVarDecl *DstDecl = ParmVarDecl::Create(
3795 C, FD, SourceLocation(), SourceLocation(), nullptr, DestTy,
3796 C.getTrivialTypeSourceInfo(DestTy, SourceLocation()), SC_None,
3797 /*DefArg=*/nullptr);
3798 args.push_back(Params[0] = DstDecl);
3799 ParmVarDecl *SrcDecl = ParmVarDecl::Create(
3800 C, FD, SourceLocation(), SourceLocation(), nullptr, SrcTy,
3801 C.getTrivialTypeSourceInfo(SrcTy, SourceLocation()), SC_None,
3802 /*DefArg=*/nullptr);
3803 args.push_back(Params[1] = SrcDecl);
3804 FD->setParams(Params);
3805
3806 const CGFunctionInfo &FI =
3807 CGM.getTypes().arrangeBuiltinFunctionDeclaration(ReturnTy, args);
3808
3809 llvm::FunctionType *LTy = CGM.getTypes().GetFunctionType(FI);
3810
3811 llvm::Function *Fn = llvm::Function::Create(
3812 LTy, llvm::GlobalValue::InternalLinkage, "__copy_helper_atomic_property_",
3813 &CGM.getModule());
3814
3815 CGM.SetInternalFunctionAttributes(GlobalDecl(), Fn, FI);
3816
3817 StartFunction(FD, ReturnTy, Fn, FI, args);
3818
3819 DeclRefExpr SrcExpr(getContext(), SrcDecl, false, SrcTy, VK_PRValue,
3820 SourceLocation());
3821
3822 UnaryOperator *SRC = UnaryOperator::Create(
3823 C, &SrcExpr, UO_Deref, SrcTy->getPointeeType(), VK_LValue, OK_Ordinary,
3824 SourceLocation(), false, FPOptionsOverride());
3825
3826 CXXConstructExpr *CXXConstExpr =
3827 cast<CXXConstructExpr>(PID->getGetterCXXConstructor());
3828
3829 SmallVector<Expr*, 4> ConstructorArgs;
3830 ConstructorArgs.push_back(SRC);
3831 ConstructorArgs.append(std::next(CXXConstExpr->arg_begin()),
3832 CXXConstExpr->arg_end());
3833
3834 CXXConstructExpr *TheCXXConstructExpr =
3835 CXXConstructExpr::Create(C, Ty, SourceLocation(),
3836 CXXConstExpr->getConstructor(),
3837 CXXConstExpr->isElidable(),
3838 ConstructorArgs,
3839 CXXConstExpr->hadMultipleCandidates(),
3840 CXXConstExpr->isListInitialization(),
3841 CXXConstExpr->isStdInitListInitialization(),
3842 CXXConstExpr->requiresZeroInitialization(),
3843 CXXConstExpr->getConstructionKind(),
3844 SourceRange());
3845
3846 DeclRefExpr DstExpr(getContext(), DstDecl, false, DestTy, VK_PRValue,
3847 SourceLocation());
3848
3849 RValue DV = EmitAnyExpr(&DstExpr);
3850 CharUnits Alignment
3851 = getContext().getTypeAlignInChars(TheCXXConstructExpr->getType());
3852 EmitAggExpr(TheCXXConstructExpr,
3853 AggValueSlot::forAddr(Address(DV.getScalarVal(), Alignment),
3854 Qualifiers(),
3855 AggValueSlot::IsDestructed,
3856 AggValueSlot::DoesNotNeedGCBarriers,
3857 AggValueSlot::IsNotAliased,
3858 AggValueSlot::DoesNotOverlap));
3859
3860 FinishFunction();
3861 HelperFn = llvm::ConstantExpr::getBitCast(Fn, VoidPtrTy);
3862 CGM.setAtomicGetterHelperFnMap(Ty, HelperFn);
3863 return HelperFn;
3864}
3865
3866llvm::Value *
3867CodeGenFunction::EmitBlockCopyAndAutorelease(llvm::Value *Block, QualType Ty) {
3868 // Get selectors for retain/autorelease.
3869 IdentifierInfo *CopyID = &getContext().Idents.get("copy");
3870 Selector CopySelector =
3871 getContext().Selectors.getNullarySelector(CopyID);
3872 IdentifierInfo *AutoreleaseID = &getContext().Idents.get("autorelease");
3873 Selector AutoreleaseSelector =
3874 getContext().Selectors.getNullarySelector(AutoreleaseID);
3875
3876 // Emit calls to retain/autorelease.
3877 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
3878 llvm::Value *Val = Block;
3879 RValue Result;
3880 Result = Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
3881 Ty, CopySelector,
3882 Val, CallArgList(), nullptr, nullptr);
3883 Val = Result.getScalarVal();
3884 Result = Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
3885 Ty, AutoreleaseSelector,
3886 Val, CallArgList(), nullptr, nullptr);
3887 Val = Result.getScalarVal();
3888 return Val;
3889}
3890
3891static unsigned getBaseMachOPlatformID(const llvm::Triple &TT) {
3892 switch (TT.getOS()) {
3893 case llvm::Triple::Darwin:
3894 case llvm::Triple::MacOSX:
3895 return llvm::MachO::PLATFORM_MACOS;
3896 case llvm::Triple::IOS:
3897 return llvm::MachO::PLATFORM_IOS;
3898 case llvm::Triple::TvOS:
3899 return llvm::MachO::PLATFORM_TVOS;
3900 case llvm::Triple::WatchOS:
3901 return llvm::MachO::PLATFORM_WATCHOS;
3902 default:
3903 return /*Unknown platform*/ 0;
3904 }
3905}
3906
3907static llvm::Value *emitIsPlatformVersionAtLeast(CodeGenFunction &CGF,
3908 const VersionTuple &Version) {
3909 CodeGenModule &CGM = CGF.CGM;
3910 // Note: we intend to support multi-platform version checks, so reserve
3911 // the room for a dual platform checking invocation that will be
3912 // implemented in the future.
3913 llvm::SmallVector<llvm::Value *, 8> Args;
3914
3915 auto EmitArgs = [&](const VersionTuple &Version, const llvm::Triple &TT) {
3916 Optional<unsigned> Min = Version.getMinor(), SMin = Version.getSubminor();
3917 Args.push_back(
3918 llvm::ConstantInt::get(CGM.Int32Ty, getBaseMachOPlatformID(TT)));
3919 Args.push_back(llvm::ConstantInt::get(CGM.Int32Ty, Version.getMajor()));
3920 Args.push_back(llvm::ConstantInt::get(CGM.Int32Ty, Min ? *Min : 0));
3921 Args.push_back(llvm::ConstantInt::get(CGM.Int32Ty, SMin ? *SMin : 0));
3922 };
3923
3924 assert(!Version.empty() && "unexpected empty version")(static_cast <bool> (!Version.empty() && "unexpected empty version"
) ? void (0) : __assert_fail ("!Version.empty() && \"unexpected empty version\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/clang/lib/CodeGen/CGObjC.cpp"
, 3924, __extension__ __PRETTY_FUNCTION__))
;
3925 EmitArgs(Version, CGM.getTarget().getTriple());
3926
3927 if (!CGM.IsPlatformVersionAtLeastFn) {
3928 llvm::FunctionType *FTy = llvm::FunctionType::get(
3929 CGM.Int32Ty, {CGM.Int32Ty, CGM.Int32Ty, CGM.Int32Ty, CGM.Int32Ty},
3930 false);
3931 CGM.IsPlatformVersionAtLeastFn =
3932 CGM.CreateRuntimeFunction(FTy, "__isPlatformVersionAtLeast");
3933 }
3934
3935 llvm::Value *Check =
3936 CGF.EmitNounwindRuntimeCall(CGM.IsPlatformVersionAtLeastFn, Args);
3937 return CGF.Builder.CreateICmpNE(Check,
3938 llvm::Constant::getNullValue(CGM.Int32Ty));
3939}
3940
3941llvm::Value *
3942CodeGenFunction::EmitBuiltinAvailable(const VersionTuple &Version) {
3943 // Darwin uses the new __isPlatformVersionAtLeast family of routines.
3944 if (CGM.getTarget().getTriple().isOSDarwin())
3945 return emitIsPlatformVersionAtLeast(*this, Version);
3946
3947 if (!CGM.IsOSVersionAtLeastFn) {
3948 llvm::FunctionType *FTy =
3949 llvm::FunctionType::get(Int32Ty, {Int32Ty, Int32Ty, Int32Ty}, false);
3950 CGM.IsOSVersionAtLeastFn =
3951 CGM.CreateRuntimeFunction(FTy, "__isOSVersionAtLeast");
3952 }
3953
3954 Optional<unsigned> Min = Version.getMinor(), SMin = Version.getSubminor();
3955 llvm::Value *Args[] = {
3956 llvm::ConstantInt::get(CGM.Int32Ty, Version.getMajor()),
3957 llvm::ConstantInt::get(CGM.Int32Ty, Min ? *Min : 0),
3958 llvm::ConstantInt::get(CGM.Int32Ty, SMin ? *SMin : 0),
3959 };
3960
3961 llvm::Value *CallRes =
3962 EmitNounwindRuntimeCall(CGM.IsOSVersionAtLeastFn, Args);
3963
3964 return Builder.CreateICmpNE(CallRes, llvm::Constant::getNullValue(Int32Ty));
3965}
3966
3967static bool isFoundationNeededForDarwinAvailabilityCheck(
3968 const llvm::Triple &TT, const VersionTuple &TargetVersion) {
3969 VersionTuple FoundationDroppedInVersion;
3970 switch (TT.getOS()) {
3971 case llvm::Triple::IOS:
3972 case llvm::Triple::TvOS:
3973 FoundationDroppedInVersion = VersionTuple(/*Major=*/13);
3974 break;
3975 case llvm::Triple::WatchOS:
3976 FoundationDroppedInVersion = VersionTuple(/*Major=*/6);
3977 break;
3978 case llvm::Triple::Darwin:
3979 case llvm::Triple::MacOSX:
3980 FoundationDroppedInVersion = VersionTuple(/*Major=*/10, /*Minor=*/15);
3981 break;
3982 default:
3983 llvm_unreachable("Unexpected OS")::llvm::llvm_unreachable_internal("Unexpected OS", "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/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() {}