1 //===---- CGBuiltin.cpp - Emit LLVM Code for builtins ---------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This contains code to emit Objective-C code as LLVM code.
12 //===----------------------------------------------------------------------===//
14 #include "CGDebugInfo.h"
15 #include "CGObjCRuntime.h"
16 #include "CodeGenFunction.h"
17 #include "CodeGenModule.h"
18 #include "TargetInfo.h"
19 #include "clang/AST/ASTContext.h"
20 #include "clang/AST/DeclObjC.h"
21 #include "clang/AST/StmtObjC.h"
22 #include "clang/Basic/Diagnostic.h"
23 #include "llvm/ADT/STLExtras.h"
24 #include "llvm/Target/TargetData.h"
25 #include "llvm/InlineAsm.h"
26 using namespace clang;
27 using namespace CodeGen;
29 typedef llvm::PointerIntPair<llvm::Value*,1,bool> TryEmitResult;
31 tryEmitARCRetainScalarExpr(CodeGenFunction &CGF, const Expr *e);
33 /// Given the address of a variable of pointer type, find the correct
34 /// null to store into it.
35 static llvm::Constant *getNullForVariable(llvm::Value *addr) {
37 cast<llvm::PointerType>(addr->getType())->getElementType();
38 return llvm::ConstantPointerNull::get(cast<llvm::PointerType>(type));
41 /// Emits an instance of NSConstantString representing the object.
42 llvm::Value *CodeGenFunction::EmitObjCStringLiteral(const ObjCStringLiteral *E)
45 CGM.getObjCRuntime().GenerateConstantString(E->getString());
46 // FIXME: This bitcast should just be made an invariant on the Runtime.
47 return llvm::ConstantExpr::getBitCast(C, ConvertType(E->getType()));
51 llvm::Value *CodeGenFunction::EmitObjCSelectorExpr(const ObjCSelectorExpr *E) {
53 // Note that this implementation allows for non-constant strings to be passed
54 // as arguments to @selector(). Currently, the only thing preventing this
55 // behaviour is the type checking in the front end.
56 return CGM.getObjCRuntime().GetSelector(Builder, E->getSelector());
59 llvm::Value *CodeGenFunction::EmitObjCProtocolExpr(const ObjCProtocolExpr *E) {
60 // FIXME: This should pass the Decl not the name.
61 return CGM.getObjCRuntime().GenerateProtocolRef(Builder, E->getProtocol());
64 /// \brief Adjust the type of the result of an Objective-C message send
65 /// expression when the method has a related result type.
66 static RValue AdjustRelatedResultType(CodeGenFunction &CGF,
68 const ObjCMethodDecl *Method,
73 if (!Method->hasRelatedResultType() ||
74 CGF.getContext().hasSameType(E->getType(), Method->getResultType()) ||
78 // We have applied a related result type. Cast the rvalue appropriately.
79 return RValue::get(CGF.Builder.CreateBitCast(Result.getScalarVal(),
80 CGF.ConvertType(E->getType())));
83 /// Decide whether to extend the lifetime of the receiver of a
84 /// returns-inner-pointer message.
86 shouldExtendReceiverForInnerPointerMessage(const ObjCMessageExpr *message) {
87 switch (message->getReceiverKind()) {
89 // For a normal instance message, we should extend unless the
90 // receiver is loaded from a variable with precise lifetime.
91 case ObjCMessageExpr::Instance: {
92 const Expr *receiver = message->getInstanceReceiver();
93 const ImplicitCastExpr *ice = dyn_cast<ImplicitCastExpr>(receiver);
94 if (!ice || ice->getCastKind() != CK_LValueToRValue) return true;
95 receiver = ice->getSubExpr()->IgnoreParens();
97 // Only __strong variables.
98 if (receiver->getType().getObjCLifetime() != Qualifiers::OCL_Strong)
101 // All ivars and fields have precise lifetime.
102 if (isa<MemberExpr>(receiver) || isa<ObjCIvarRefExpr>(receiver))
105 // Otherwise, check for variables.
106 const DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(ice->getSubExpr());
107 if (!declRef) return true;
108 const VarDecl *var = dyn_cast<VarDecl>(declRef->getDecl());
109 if (!var) return true;
111 // All variables have precise lifetime except local variables with
112 // automatic storage duration that aren't specially marked.
113 return (var->hasLocalStorage() &&
114 !var->hasAttr<ObjCPreciseLifetimeAttr>());
117 case ObjCMessageExpr::Class:
118 case ObjCMessageExpr::SuperClass:
119 // It's never necessary for class objects.
122 case ObjCMessageExpr::SuperInstance:
123 // We generally assume that 'self' lives throughout a method call.
127 llvm_unreachable("invalid receiver kind");
130 RValue CodeGenFunction::EmitObjCMessageExpr(const ObjCMessageExpr *E,
131 ReturnValueSlot Return) {
132 // Only the lookup mechanism and first two arguments of the method
133 // implementation vary between runtimes. We can get the receiver and
134 // arguments in generic code.
136 bool isDelegateInit = E->isDelegateInitCall();
138 const ObjCMethodDecl *method = E->getMethodDecl();
140 // We don't retain the receiver in delegate init calls, and this is
141 // safe because the receiver value is always loaded from 'self',
142 // which we zero out. We don't want to Block_copy block receivers,
146 CGM.getLangOptions().ObjCAutoRefCount &&
148 method->hasAttr<NSConsumesSelfAttr>());
150 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
151 bool isSuperMessage = false;
152 bool isClassMessage = false;
153 ObjCInterfaceDecl *OID = 0;
155 QualType ReceiverType;
156 llvm::Value *Receiver = 0;
157 switch (E->getReceiverKind()) {
158 case ObjCMessageExpr::Instance:
159 ReceiverType = E->getInstanceReceiver()->getType();
161 TryEmitResult ter = tryEmitARCRetainScalarExpr(*this,
162 E->getInstanceReceiver());
163 Receiver = ter.getPointer();
164 if (ter.getInt()) retainSelf = false;
166 Receiver = EmitScalarExpr(E->getInstanceReceiver());
169 case ObjCMessageExpr::Class: {
170 ReceiverType = E->getClassReceiver();
171 const ObjCObjectType *ObjTy = ReceiverType->getAs<ObjCObjectType>();
172 assert(ObjTy && "Invalid Objective-C class message send");
173 OID = ObjTy->getInterface();
174 assert(OID && "Invalid Objective-C class message send");
175 Receiver = Runtime.GetClass(Builder, OID);
176 isClassMessage = true;
180 case ObjCMessageExpr::SuperInstance:
181 ReceiverType = E->getSuperType();
182 Receiver = LoadObjCSelf();
183 isSuperMessage = true;
186 case ObjCMessageExpr::SuperClass:
187 ReceiverType = E->getSuperType();
188 Receiver = LoadObjCSelf();
189 isSuperMessage = true;
190 isClassMessage = true;
195 Receiver = EmitARCRetainNonBlock(Receiver);
197 // In ARC, we sometimes want to "extend the lifetime"
198 // (i.e. retain+autorelease) of receivers of returns-inner-pointer
200 if (getLangOptions().ObjCAutoRefCount && method &&
201 method->hasAttr<ObjCReturnsInnerPointerAttr>() &&
202 shouldExtendReceiverForInnerPointerMessage(E))
203 Receiver = EmitARCRetainAutorelease(ReceiverType, Receiver);
205 QualType ResultType =
206 method ? method->getResultType() : E->getType();
209 EmitCallArgs(Args, method, E->arg_begin(), E->arg_end());
211 // For delegate init calls in ARC, do an unsafe store of null into
212 // self. This represents the call taking direct ownership of that
213 // value. We have to do this after emitting the other call
214 // arguments because they might also reference self, but we don't
215 // have to worry about any of them modifying self because that would
216 // be an undefined read and write of an object in unordered
218 if (isDelegateInit) {
219 assert(getLangOptions().ObjCAutoRefCount &&
220 "delegate init calls should only be marked in ARC");
222 // Do an unsafe store of null into self.
223 llvm::Value *selfAddr =
224 LocalDeclMap[cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl()];
225 assert(selfAddr && "no self entry for a delegate init call?");
227 Builder.CreateStore(getNullForVariable(selfAddr), selfAddr);
231 if (isSuperMessage) {
232 // super is only valid in an Objective-C method
233 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
234 bool isCategoryImpl = isa<ObjCCategoryImplDecl>(OMD->getDeclContext());
235 result = Runtime.GenerateMessageSendSuper(*this, Return, ResultType,
237 OMD->getClassInterface(),
244 result = Runtime.GenerateMessageSend(*this, Return, ResultType,
250 // For delegate init calls in ARC, implicitly store the result of
251 // the call back into self. This takes ownership of the value.
252 if (isDelegateInit) {
253 llvm::Value *selfAddr =
254 LocalDeclMap[cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl()];
255 llvm::Value *newSelf = result.getScalarVal();
257 // The delegate return type isn't necessarily a matching type; in
258 // fact, it's quite likely to be 'id'.
260 cast<llvm::PointerType>(selfAddr->getType())->getElementType();
261 newSelf = Builder.CreateBitCast(newSelf, selfTy);
263 Builder.CreateStore(newSelf, selfAddr);
266 return AdjustRelatedResultType(*this, E, method, result);
270 struct FinishARCDealloc : EHScopeStack::Cleanup {
271 void Emit(CodeGenFunction &CGF, Flags flags) {
272 const ObjCMethodDecl *method = cast<ObjCMethodDecl>(CGF.CurCodeDecl);
274 const ObjCImplDecl *impl = cast<ObjCImplDecl>(method->getDeclContext());
275 const ObjCInterfaceDecl *iface = impl->getClassInterface();
276 if (!iface->getSuperClass()) return;
278 bool isCategory = isa<ObjCCategoryImplDecl>(impl);
280 // Call [super dealloc] if we have a superclass.
281 llvm::Value *self = CGF.LoadObjCSelf();
284 CGF.CGM.getObjCRuntime().GenerateMessageSendSuper(CGF, ReturnValueSlot(),
285 CGF.getContext().VoidTy,
286 method->getSelector(),
290 /*is class msg*/ false,
297 /// StartObjCMethod - Begin emission of an ObjCMethod. This generates
298 /// the LLVM function and sets the other context used by
300 void CodeGenFunction::StartObjCMethod(const ObjCMethodDecl *OMD,
301 const ObjCContainerDecl *CD,
302 SourceLocation StartLoc) {
303 FunctionArgList args;
304 // Check if we should generate debug info for this method.
305 if (CGM.getModuleDebugInfo() && !OMD->hasAttr<NoDebugAttr>())
306 DebugInfo = CGM.getModuleDebugInfo();
308 llvm::Function *Fn = CGM.getObjCRuntime().GenerateMethod(OMD, CD);
310 const CGFunctionInfo &FI = CGM.getTypes().getFunctionInfo(OMD);
311 CGM.SetInternalFunctionAttributes(OMD, Fn, FI);
313 args.push_back(OMD->getSelfDecl());
314 args.push_back(OMD->getCmdDecl());
316 for (ObjCMethodDecl::param_const_iterator PI = OMD->param_begin(),
317 E = OMD->param_end(); PI != E; ++PI)
322 StartFunction(OMD, OMD->getResultType(), Fn, FI, args, StartLoc);
324 // In ARC, certain methods get an extra cleanup.
325 if (CGM.getLangOptions().ObjCAutoRefCount &&
326 OMD->isInstanceMethod() &&
327 OMD->getSelector().isUnarySelector()) {
328 const IdentifierInfo *ident =
329 OMD->getSelector().getIdentifierInfoForSlot(0);
330 if (ident->isStr("dealloc"))
331 EHStack.pushCleanup<FinishARCDealloc>(getARCCleanupKind());
335 static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF,
336 LValue lvalue, QualType type);
338 /// Generate an Objective-C method. An Objective-C method is a C function with
339 /// its pointer, name, and types registered in the class struture.
340 void CodeGenFunction::GenerateObjCMethod(const ObjCMethodDecl *OMD) {
341 StartObjCMethod(OMD, OMD->getClassInterface(), OMD->getLocStart());
342 EmitStmt(OMD->getBody());
343 FinishFunction(OMD->getBodyRBrace());
346 /// emitStructGetterCall - Call the runtime function to load a property
347 /// into the return value slot.
348 static void emitStructGetterCall(CodeGenFunction &CGF, ObjCIvarDecl *ivar,
349 bool isAtomic, bool hasStrong) {
350 ASTContext &Context = CGF.getContext();
353 CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), CGF.LoadObjCSelf(),
354 ivar, 0).getAddress();
356 // objc_copyStruct (ReturnValue, &structIvar,
357 // sizeof (Type of Ivar), isAtomic, false);
360 llvm::Value *dest = CGF.Builder.CreateBitCast(CGF.ReturnValue, CGF.VoidPtrTy);
361 args.add(RValue::get(dest), Context.VoidPtrTy);
363 src = CGF.Builder.CreateBitCast(src, CGF.VoidPtrTy);
364 args.add(RValue::get(src), Context.VoidPtrTy);
366 CharUnits size = CGF.getContext().getTypeSizeInChars(ivar->getType());
367 args.add(RValue::get(CGF.CGM.getSize(size)), Context.getSizeType());
368 args.add(RValue::get(CGF.Builder.getInt1(isAtomic)), Context.BoolTy);
369 args.add(RValue::get(CGF.Builder.getInt1(hasStrong)), Context.BoolTy);
371 llvm::Value *fn = CGF.CGM.getObjCRuntime().GetGetStructFunction();
372 CGF.EmitCall(CGF.getTypes().getFunctionInfo(Context.VoidTy, args,
373 FunctionType::ExtInfo()),
374 fn, ReturnValueSlot(), args);
377 /// Determine whether the given architecture supports unaligned atomic
378 /// accesses. They don't have to be fast, just faster than a function
379 /// call and a mutex.
380 static bool hasUnalignedAtomics(llvm::Triple::ArchType arch) {
381 // FIXME: Allow unaligned atomic load/store on x86. (It is not
382 // currently supported by the backend.)
386 /// Return the maximum size that permits atomic accesses for the given
388 static CharUnits getMaxAtomicAccessSize(CodeGenModule &CGM,
389 llvm::Triple::ArchType arch) {
390 // ARM has 8-byte atomic accesses, but it's not clear whether we
391 // want to rely on them here.
393 // In the default case, just assume that any size up to a pointer is
394 // fine given adequate alignment.
395 return CharUnits::fromQuantity(CGM.PointerSizeInBytes);
399 class PropertyImplStrategy {
402 /// The 'native' strategy is to use the architecture's provided
403 /// reads and writes.
406 /// Use objc_setProperty and objc_getProperty.
409 /// Use objc_setProperty for the setter, but use expression
410 /// evaluation for the getter.
411 SetPropertyAndExpressionGet,
413 /// Use objc_copyStruct.
416 /// The 'expression' strategy is to emit normal assignment or
417 /// lvalue-to-rvalue expressions.
421 StrategyKind getKind() const { return StrategyKind(Kind); }
423 bool hasStrongMember() const { return HasStrong; }
424 bool isAtomic() const { return IsAtomic; }
425 bool isCopy() const { return IsCopy; }
427 CharUnits getIvarSize() const { return IvarSize; }
428 CharUnits getIvarAlignment() const { return IvarAlignment; }
430 PropertyImplStrategy(CodeGenModule &CGM,
431 const ObjCPropertyImplDecl *propImpl);
435 unsigned IsAtomic : 1;
437 unsigned HasStrong : 1;
440 CharUnits IvarAlignment;
444 /// Pick an implementation strategy for the the given property synthesis.
445 PropertyImplStrategy::PropertyImplStrategy(CodeGenModule &CGM,
446 const ObjCPropertyImplDecl *propImpl) {
447 const ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
448 ObjCPropertyDecl::SetterKind setterKind = prop->getSetterKind();
450 IsCopy = (setterKind == ObjCPropertyDecl::Copy);
451 IsAtomic = prop->isAtomic();
452 HasStrong = false; // doesn't matter here.
454 // Evaluate the ivar's size and alignment.
455 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
456 QualType ivarType = ivar->getType();
457 llvm::tie(IvarSize, IvarAlignment)
458 = CGM.getContext().getTypeInfoInChars(ivarType);
460 // If we have a copy property, we always have to use getProperty/setProperty.
461 // TODO: we could actually use setProperty and an expression for non-atomics.
463 Kind = GetSetProperty;
468 if (setterKind == ObjCPropertyDecl::Retain) {
469 // In GC-only, there's nothing special that needs to be done.
470 if (CGM.getLangOptions().getGC() == LangOptions::GCOnly) {
473 // In ARC, if the property is non-atomic, use expression emission,
474 // which translates to objc_storeStrong. This isn't required, but
475 // it's slightly nicer.
476 } else if (CGM.getLangOptions().ObjCAutoRefCount && !IsAtomic) {
480 // Otherwise, we need to at least use setProperty. However, if
481 // the property isn't atomic, we can use normal expression
482 // emission for the getter.
483 } else if (!IsAtomic) {
484 Kind = SetPropertyAndExpressionGet;
487 // Otherwise, we have to use both setProperty and getProperty.
489 Kind = GetSetProperty;
494 // If we're not atomic, just use expression accesses.
500 // Properties on bitfield ivars need to be emitted using expression
501 // accesses even if they're nominally atomic.
502 if (ivar->isBitField()) {
507 // GC-qualified or ARC-qualified ivars need to be emitted as
508 // expressions. This actually works out to being atomic anyway,
509 // except for ARC __strong, but that should trigger the above code.
510 if (ivarType.hasNonTrivialObjCLifetime() ||
511 (CGM.getLangOptions().getGC() &&
512 CGM.getContext().getObjCGCAttrKind(ivarType))) {
517 // Compute whether the ivar has strong members.
518 if (CGM.getLangOptions().getGC())
519 if (const RecordType *recordType = ivarType->getAs<RecordType>())
520 HasStrong = recordType->getDecl()->hasObjectMember();
522 // We can never access structs with object members with a native
523 // access, because we need to use write barriers. This is what
524 // objc_copyStruct is for.
530 // Otherwise, this is target-dependent and based on the size and
531 // alignment of the ivar.
533 // If the size of the ivar is not a power of two, give up. We don't
534 // want to get into the business of doing compare-and-swaps.
535 if (!IvarSize.isPowerOfTwo()) {
540 llvm::Triple::ArchType arch =
541 CGM.getContext().getTargetInfo().getTriple().getArch();
543 // Most architectures require memory to fit within a single cache
544 // line, so the alignment has to be at least the size of the access.
545 // Otherwise we have to grab a lock.
546 if (IvarAlignment < IvarSize && !hasUnalignedAtomics(arch)) {
551 // If the ivar's size exceeds the architecture's maximum atomic
552 // access size, we have to use CopyStruct.
553 if (IvarSize > getMaxAtomicAccessSize(CGM, arch)) {
558 // Otherwise, we can use native loads and stores.
562 /// GenerateObjCGetter - Generate an Objective-C property getter
563 /// function. The given Decl must be an ObjCImplementationDecl. @synthesize
564 /// is illegal within a category.
565 void CodeGenFunction::GenerateObjCGetter(ObjCImplementationDecl *IMP,
566 const ObjCPropertyImplDecl *PID) {
567 const ObjCPropertyDecl *PD = PID->getPropertyDecl();
568 ObjCMethodDecl *OMD = PD->getGetterMethodDecl();
569 assert(OMD && "Invalid call to generate getter (empty method)");
570 StartObjCMethod(OMD, IMP->getClassInterface(), PID->getLocStart());
572 generateObjCGetterBody(IMP, PID);
577 static bool hasTrivialGetExpr(const ObjCPropertyImplDecl *propImpl) {
578 const Expr *getter = propImpl->getGetterCXXConstructor();
579 if (!getter) return true;
581 // Sema only makes only of these when the ivar has a C++ class type,
582 // so the form is pretty constrained.
584 // If the property has a reference type, we might just be binding a
585 // reference, in which case the result will be a gl-value. We should
586 // treat this as a non-trivial operation.
587 if (getter->isGLValue())
590 // If we selected a trivial copy-constructor, we're okay.
591 if (const CXXConstructExpr *construct = dyn_cast<CXXConstructExpr>(getter))
592 return (construct->getConstructor()->isTrivial());
594 // The constructor might require cleanups (in which case it's never
596 assert(isa<ExprWithCleanups>(getter));
601 CodeGenFunction::generateObjCGetterBody(const ObjCImplementationDecl *classImpl,
602 const ObjCPropertyImplDecl *propImpl) {
603 // If there's a non-trivial 'get' expression, we just have to emit that.
604 if (!hasTrivialGetExpr(propImpl)) {
605 ReturnStmt ret(SourceLocation(), propImpl->getGetterCXXConstructor(),
611 const ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
612 QualType propType = prop->getType();
613 ObjCMethodDecl *getterMethod = prop->getGetterMethodDecl();
615 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
617 // Pick an implementation strategy.
618 PropertyImplStrategy strategy(CGM, propImpl);
619 switch (strategy.getKind()) {
620 case PropertyImplStrategy::Native: {
621 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar, 0);
623 // Currently, all atomic accesses have to be through integer
624 // types, so there's no point in trying to pick a prettier type.
625 llvm::Type *bitcastType =
626 llvm::Type::getIntNTy(getLLVMContext(),
627 getContext().toBits(strategy.getIvarSize()));
628 bitcastType = bitcastType->getPointerTo(); // addrspace 0 okay
630 // Perform an atomic load. This does not impose ordering constraints.
631 llvm::Value *ivarAddr = LV.getAddress();
632 ivarAddr = Builder.CreateBitCast(ivarAddr, bitcastType);
633 llvm::LoadInst *load = Builder.CreateLoad(ivarAddr, "load");
634 load->setAlignment(strategy.getIvarAlignment().getQuantity());
635 load->setAtomic(llvm::Unordered);
637 // Store that value into the return address. Doing this with a
638 // bitcast is likely to produce some pretty ugly IR, but it's not
639 // the *most* terrible thing in the world.
640 Builder.CreateStore(load, Builder.CreateBitCast(ReturnValue, bitcastType));
642 // Make sure we don't do an autorelease.
643 AutoreleaseResult = false;
647 case PropertyImplStrategy::GetSetProperty: {
648 llvm::Value *getPropertyFn =
649 CGM.getObjCRuntime().GetPropertyGetFunction();
650 if (!getPropertyFn) {
651 CGM.ErrorUnsupported(propImpl, "Obj-C getter requiring atomic copy");
655 // Return (ivar-type) objc_getProperty((id) self, _cmd, offset, true).
656 // FIXME: Can't this be simpler? This might even be worse than the
657 // corresponding gcc code.
659 Builder.CreateLoad(LocalDeclMap[getterMethod->getCmdDecl()], "cmd");
660 llvm::Value *self = Builder.CreateBitCast(LoadObjCSelf(), VoidPtrTy);
661 llvm::Value *ivarOffset =
662 EmitIvarOffset(classImpl->getClassInterface(), ivar);
665 args.add(RValue::get(self), getContext().getObjCIdType());
666 args.add(RValue::get(cmd), getContext().getObjCSelType());
667 args.add(RValue::get(ivarOffset), getContext().getPointerDiffType());
668 args.add(RValue::get(Builder.getInt1(strategy.isAtomic())),
669 getContext().BoolTy);
671 // FIXME: We shouldn't need to get the function info here, the
672 // runtime already should have computed it to build the function.
673 RValue RV = EmitCall(getTypes().getFunctionInfo(propType, args,
674 FunctionType::ExtInfo()),
675 getPropertyFn, ReturnValueSlot(), args);
677 // We need to fix the type here. Ivars with copy & retain are
678 // always objects so we don't need to worry about complex or
680 RV = RValue::get(Builder.CreateBitCast(RV.getScalarVal(),
681 getTypes().ConvertType(propType)));
683 EmitReturnOfRValue(RV, propType);
685 // objc_getProperty does an autorelease, so we should suppress ours.
686 AutoreleaseResult = false;
691 case PropertyImplStrategy::CopyStruct:
692 emitStructGetterCall(*this, ivar, strategy.isAtomic(),
693 strategy.hasStrongMember());
696 case PropertyImplStrategy::Expression:
697 case PropertyImplStrategy::SetPropertyAndExpressionGet: {
698 LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar, 0);
700 QualType ivarType = ivar->getType();
701 if (ivarType->isAnyComplexType()) {
702 ComplexPairTy pair = LoadComplexFromAddr(LV.getAddress(),
703 LV.isVolatileQualified());
704 StoreComplexToAddr(pair, ReturnValue, LV.isVolatileQualified());
705 } else if (hasAggregateLLVMType(ivarType)) {
706 // The return value slot is guaranteed to not be aliased, but
707 // that's not necessarily the same as "on the stack", so
708 // we still potentially need objc_memmove_collectable.
709 EmitAggregateCopy(ReturnValue, LV.getAddress(), ivarType);
712 if (propType->isReferenceType()) {
713 value = LV.getAddress();
715 // We want to load and autoreleaseReturnValue ARC __weak ivars.
716 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
717 value = emitARCRetainLoadOfScalar(*this, LV, ivarType);
719 // Otherwise we want to do a simple load, suppressing the
720 // final autorelease.
722 value = EmitLoadOfLValue(LV).getScalarVal();
723 AutoreleaseResult = false;
726 value = Builder.CreateBitCast(value, ConvertType(propType));
729 EmitReturnOfRValue(RValue::get(value), propType);
735 llvm_unreachable("bad @property implementation strategy!");
738 /// emitStructSetterCall - Call the runtime function to store the value
739 /// from the first formal parameter into the given ivar.
740 static void emitStructSetterCall(CodeGenFunction &CGF, ObjCMethodDecl *OMD,
741 ObjCIvarDecl *ivar) {
742 // objc_copyStruct (&structIvar, &Arg,
743 // sizeof (struct something), true, false);
746 // The first argument is the address of the ivar.
747 llvm::Value *ivarAddr = CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(),
748 CGF.LoadObjCSelf(), ivar, 0)
750 ivarAddr = CGF.Builder.CreateBitCast(ivarAddr, CGF.Int8PtrTy);
751 args.add(RValue::get(ivarAddr), CGF.getContext().VoidPtrTy);
753 // The second argument is the address of the parameter variable.
754 ParmVarDecl *argVar = *OMD->param_begin();
755 DeclRefExpr argRef(argVar, argVar->getType(), VK_LValue, SourceLocation());
756 llvm::Value *argAddr = CGF.EmitLValue(&argRef).getAddress();
757 argAddr = CGF.Builder.CreateBitCast(argAddr, CGF.Int8PtrTy);
758 args.add(RValue::get(argAddr), CGF.getContext().VoidPtrTy);
760 // The third argument is the sizeof the type.
762 CGF.CGM.getSize(CGF.getContext().getTypeSizeInChars(ivar->getType()));
763 args.add(RValue::get(size), CGF.getContext().getSizeType());
765 // The fourth argument is the 'isAtomic' flag.
766 args.add(RValue::get(CGF.Builder.getTrue()), CGF.getContext().BoolTy);
768 // The fifth argument is the 'hasStrong' flag.
769 // FIXME: should this really always be false?
770 args.add(RValue::get(CGF.Builder.getFalse()), CGF.getContext().BoolTy);
772 llvm::Value *copyStructFn = CGF.CGM.getObjCRuntime().GetSetStructFunction();
773 CGF.EmitCall(CGF.getTypes().getFunctionInfo(CGF.getContext().VoidTy, args,
774 FunctionType::ExtInfo()),
775 copyStructFn, ReturnValueSlot(), args);
778 static bool hasTrivialSetExpr(const ObjCPropertyImplDecl *PID) {
779 Expr *setter = PID->getSetterCXXAssignment();
780 if (!setter) return true;
782 // Sema only makes only of these when the ivar has a C++ class type,
783 // so the form is pretty constrained.
785 // An operator call is trivial if the function it calls is trivial.
786 // This also implies that there's nothing non-trivial going on with
787 // the arguments, because operator= can only be trivial if it's a
788 // synthesized assignment operator and therefore both parameters are
790 if (CallExpr *call = dyn_cast<CallExpr>(setter)) {
791 if (const FunctionDecl *callee
792 = dyn_cast_or_null<FunctionDecl>(call->getCalleeDecl()))
793 if (callee->isTrivial())
798 assert(isa<ExprWithCleanups>(setter));
803 CodeGenFunction::generateObjCSetterBody(const ObjCImplementationDecl *classImpl,
804 const ObjCPropertyImplDecl *propImpl) {
805 // Just use the setter expression if Sema gave us one and it's
806 // non-trivial. There's no way to do this atomically.
807 if (!hasTrivialSetExpr(propImpl)) {
808 EmitStmt(propImpl->getSetterCXXAssignment());
812 const ObjCPropertyDecl *prop = propImpl->getPropertyDecl();
813 ObjCIvarDecl *ivar = propImpl->getPropertyIvarDecl();
814 ObjCMethodDecl *setterMethod = prop->getSetterMethodDecl();
816 PropertyImplStrategy strategy(CGM, propImpl);
817 switch (strategy.getKind()) {
818 case PropertyImplStrategy::Native: {
819 llvm::Value *argAddr = LocalDeclMap[*setterMethod->param_begin()];
822 EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), ivar, /*quals*/ 0);
823 llvm::Value *ivarAddr = ivarLValue.getAddress();
825 // Currently, all atomic accesses have to be through integer
826 // types, so there's no point in trying to pick a prettier type.
827 llvm::Type *bitcastType =
828 llvm::Type::getIntNTy(getLLVMContext(),
829 getContext().toBits(strategy.getIvarSize()));
830 bitcastType = bitcastType->getPointerTo(); // addrspace 0 okay
832 // Cast both arguments to the chosen operation type.
833 argAddr = Builder.CreateBitCast(argAddr, bitcastType);
834 ivarAddr = Builder.CreateBitCast(ivarAddr, bitcastType);
836 // This bitcast load is likely to cause some nasty IR.
837 llvm::Value *load = Builder.CreateLoad(argAddr);
839 // Perform an atomic store. There are no memory ordering requirements.
840 llvm::StoreInst *store = Builder.CreateStore(load, ivarAddr);
841 store->setAlignment(strategy.getIvarAlignment().getQuantity());
842 store->setAtomic(llvm::Unordered);
846 case PropertyImplStrategy::GetSetProperty:
847 case PropertyImplStrategy::SetPropertyAndExpressionGet: {
848 llvm::Value *setPropertyFn =
849 CGM.getObjCRuntime().GetPropertySetFunction();
850 if (!setPropertyFn) {
851 CGM.ErrorUnsupported(propImpl, "Obj-C setter requiring atomic copy");
855 // Emit objc_setProperty((id) self, _cmd, offset, arg,
856 // <is-atomic>, <is-copy>).
858 Builder.CreateLoad(LocalDeclMap[setterMethod->getCmdDecl()]);
860 Builder.CreateBitCast(LoadObjCSelf(), VoidPtrTy);
861 llvm::Value *ivarOffset =
862 EmitIvarOffset(classImpl->getClassInterface(), ivar);
863 llvm::Value *arg = LocalDeclMap[*setterMethod->param_begin()];
864 arg = Builder.CreateBitCast(Builder.CreateLoad(arg, "arg"), VoidPtrTy);
867 args.add(RValue::get(self), getContext().getObjCIdType());
868 args.add(RValue::get(cmd), getContext().getObjCSelType());
869 args.add(RValue::get(ivarOffset), getContext().getPointerDiffType());
870 args.add(RValue::get(arg), getContext().getObjCIdType());
871 args.add(RValue::get(Builder.getInt1(strategy.isAtomic())),
872 getContext().BoolTy);
873 args.add(RValue::get(Builder.getInt1(strategy.isCopy())),
874 getContext().BoolTy);
875 // FIXME: We shouldn't need to get the function info here, the runtime
876 // already should have computed it to build the function.
877 EmitCall(getTypes().getFunctionInfo(getContext().VoidTy, args,
878 FunctionType::ExtInfo()),
879 setPropertyFn, ReturnValueSlot(), args);
883 case PropertyImplStrategy::CopyStruct:
884 emitStructSetterCall(*this, setterMethod, ivar);
887 case PropertyImplStrategy::Expression:
891 // Otherwise, fake up some ASTs and emit a normal assignment.
892 ValueDecl *selfDecl = setterMethod->getSelfDecl();
893 DeclRefExpr self(selfDecl, selfDecl->getType(), VK_LValue, SourceLocation());
894 ImplicitCastExpr selfLoad(ImplicitCastExpr::OnStack,
895 selfDecl->getType(), CK_LValueToRValue, &self,
897 ObjCIvarRefExpr ivarRef(ivar, ivar->getType().getNonReferenceType(),
898 SourceLocation(), &selfLoad, true, true);
900 ParmVarDecl *argDecl = *setterMethod->param_begin();
901 QualType argType = argDecl->getType().getNonReferenceType();
902 DeclRefExpr arg(argDecl, argType, VK_LValue, SourceLocation());
903 ImplicitCastExpr argLoad(ImplicitCastExpr::OnStack,
904 argType.getUnqualifiedType(), CK_LValueToRValue,
907 // The property type can differ from the ivar type in some situations with
908 // Objective-C pointer types, we can always bit cast the RHS in these cases.
909 // The following absurdity is just to ensure well-formed IR.
910 CastKind argCK = CK_NoOp;
911 if (ivarRef.getType()->isObjCObjectPointerType()) {
912 if (argLoad.getType()->isObjCObjectPointerType())
914 else if (argLoad.getType()->isBlockPointerType())
915 argCK = CK_BlockPointerToObjCPointerCast;
917 argCK = CK_CPointerToObjCPointerCast;
918 } else if (ivarRef.getType()->isBlockPointerType()) {
919 if (argLoad.getType()->isBlockPointerType())
922 argCK = CK_AnyPointerToBlockPointerCast;
923 } else if (ivarRef.getType()->isPointerType()) {
926 ImplicitCastExpr argCast(ImplicitCastExpr::OnStack,
927 ivarRef.getType(), argCK, &argLoad,
929 Expr *finalArg = &argLoad;
930 if (!getContext().hasSameUnqualifiedType(ivarRef.getType(),
935 BinaryOperator assign(&ivarRef, finalArg, BO_Assign,
936 ivarRef.getType(), VK_RValue, OK_Ordinary,
941 /// GenerateObjCSetter - Generate an Objective-C property setter
942 /// function. The given Decl must be an ObjCImplementationDecl. @synthesize
943 /// is illegal within a category.
944 void CodeGenFunction::GenerateObjCSetter(ObjCImplementationDecl *IMP,
945 const ObjCPropertyImplDecl *PID) {
946 const ObjCPropertyDecl *PD = PID->getPropertyDecl();
947 ObjCMethodDecl *OMD = PD->getSetterMethodDecl();
948 assert(OMD && "Invalid call to generate setter (empty method)");
949 StartObjCMethod(OMD, IMP->getClassInterface(), PID->getLocStart());
951 generateObjCSetterBody(IMP, PID);
957 struct DestroyIvar : EHScopeStack::Cleanup {
960 const ObjCIvarDecl *ivar;
961 CodeGenFunction::Destroyer &destroyer;
962 bool useEHCleanupForArray;
964 DestroyIvar(llvm::Value *addr, const ObjCIvarDecl *ivar,
965 CodeGenFunction::Destroyer *destroyer,
966 bool useEHCleanupForArray)
967 : addr(addr), ivar(ivar), destroyer(*destroyer),
968 useEHCleanupForArray(useEHCleanupForArray) {}
970 void Emit(CodeGenFunction &CGF, Flags flags) {
972 = CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), addr, ivar, /*CVR*/ 0);
973 CGF.emitDestroy(lvalue.getAddress(), ivar->getType(), destroyer,
974 flags.isForNormalCleanup() && useEHCleanupForArray);
979 /// Like CodeGenFunction::destroyARCStrong, but do it with a call.
980 static void destroyARCStrongWithStore(CodeGenFunction &CGF,
983 llvm::Value *null = getNullForVariable(addr);
984 CGF.EmitARCStoreStrongCall(addr, null, /*ignored*/ true);
987 static void emitCXXDestructMethod(CodeGenFunction &CGF,
988 ObjCImplementationDecl *impl) {
989 CodeGenFunction::RunCleanupsScope scope(CGF);
991 llvm::Value *self = CGF.LoadObjCSelf();
993 const ObjCInterfaceDecl *iface = impl->getClassInterface();
994 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
995 ivar; ivar = ivar->getNextIvar()) {
996 QualType type = ivar->getType();
998 // Check whether the ivar is a destructible type.
999 QualType::DestructionKind dtorKind = type.isDestructedType();
1000 if (!dtorKind) continue;
1002 CodeGenFunction::Destroyer *destroyer = 0;
1004 // Use a call to objc_storeStrong to destroy strong ivars, for the
1005 // general benefit of the tools.
1006 if (dtorKind == QualType::DK_objc_strong_lifetime) {
1007 destroyer = &destroyARCStrongWithStore;
1009 // Otherwise use the default for the destruction kind.
1011 destroyer = &CGF.getDestroyer(dtorKind);
1014 CleanupKind cleanupKind = CGF.getCleanupKind(dtorKind);
1016 CGF.EHStack.pushCleanup<DestroyIvar>(cleanupKind, self, ivar, destroyer,
1017 cleanupKind & EHCleanup);
1020 assert(scope.requiresCleanups() && "nothing to do in .cxx_destruct?");
1023 void CodeGenFunction::GenerateObjCCtorDtorMethod(ObjCImplementationDecl *IMP,
1026 MD->createImplicitParams(CGM.getContext(), IMP->getClassInterface());
1027 StartObjCMethod(MD, IMP->getClassInterface(), MD->getLocStart());
1029 // Emit .cxx_construct.
1031 // Suppress the final autorelease in ARC.
1032 AutoreleaseResult = false;
1034 SmallVector<CXXCtorInitializer *, 8> IvarInitializers;
1035 for (ObjCImplementationDecl::init_const_iterator B = IMP->init_begin(),
1036 E = IMP->init_end(); B != E; ++B) {
1037 CXXCtorInitializer *IvarInit = (*B);
1038 FieldDecl *Field = IvarInit->getAnyMember();
1039 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(Field);
1040 LValue LV = EmitLValueForIvar(TypeOfSelfObject(),
1041 LoadObjCSelf(), Ivar, 0);
1042 EmitAggExpr(IvarInit->getInit(),
1043 AggValueSlot::forLValue(LV, AggValueSlot::IsDestructed,
1044 AggValueSlot::DoesNotNeedGCBarriers,
1045 AggValueSlot::IsNotAliased));
1047 // constructor returns 'self'.
1048 CodeGenTypes &Types = CGM.getTypes();
1049 QualType IdTy(CGM.getContext().getObjCIdType());
1050 llvm::Value *SelfAsId =
1051 Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy));
1052 EmitReturnOfRValue(RValue::get(SelfAsId), IdTy);
1054 // Emit .cxx_destruct.
1056 emitCXXDestructMethod(*this, IMP);
1061 bool CodeGenFunction::IndirectObjCSetterArg(const CGFunctionInfo &FI) {
1062 CGFunctionInfo::const_arg_iterator it = FI.arg_begin();
1064 const ABIArgInfo &AI = it->info;
1065 // FIXME. Is this sufficient check?
1066 return (AI.getKind() == ABIArgInfo::Indirect);
1069 bool CodeGenFunction::IvarTypeWithAggrGCObjects(QualType Ty) {
1070 if (CGM.getLangOptions().getGC() == LangOptions::NonGC)
1072 if (const RecordType *FDTTy = Ty.getTypePtr()->getAs<RecordType>())
1073 return FDTTy->getDecl()->hasObjectMember();
1077 llvm::Value *CodeGenFunction::LoadObjCSelf() {
1078 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
1079 return Builder.CreateLoad(LocalDeclMap[OMD->getSelfDecl()], "self");
1082 QualType CodeGenFunction::TypeOfSelfObject() {
1083 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
1084 ImplicitParamDecl *selfDecl = OMD->getSelfDecl();
1085 const ObjCObjectPointerType *PTy = cast<ObjCObjectPointerType>(
1086 getContext().getCanonicalType(selfDecl->getType()));
1087 return PTy->getPointeeType();
1091 CodeGenFunction::EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E) {
1092 // This is a special l-value that just issues sends when we load or
1093 // store through it.
1095 // For certain base kinds, we need to emit the base immediately.
1097 if (E->isSuperReceiver())
1098 Base = LoadObjCSelf();
1099 else if (E->isClassReceiver())
1100 Base = CGM.getObjCRuntime().GetClass(Builder, E->getClassReceiver());
1102 Base = EmitScalarExpr(E->getBase());
1103 return LValue::MakePropertyRef(E, Base);
1106 static RValue GenerateMessageSendSuper(CodeGenFunction &CGF,
1107 ReturnValueSlot Return,
1108 QualType ResultType,
1110 llvm::Value *Receiver,
1111 const CallArgList &CallArgs) {
1112 const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CGF.CurFuncDecl);
1113 bool isClassMessage = OMD->isClassMethod();
1114 bool isCategoryImpl = isa<ObjCCategoryImplDecl>(OMD->getDeclContext());
1115 return CGF.CGM.getObjCRuntime()
1116 .GenerateMessageSendSuper(CGF, Return, ResultType,
1117 S, OMD->getClassInterface(),
1118 isCategoryImpl, Receiver,
1119 isClassMessage, CallArgs);
1122 RValue CodeGenFunction::EmitLoadOfPropertyRefLValue(LValue LV,
1123 ReturnValueSlot Return) {
1124 const ObjCPropertyRefExpr *E = LV.getPropertyRefExpr();
1125 QualType ResultType = E->getGetterResultType();
1127 const ObjCMethodDecl *method;
1128 if (E->isExplicitProperty()) {
1129 const ObjCPropertyDecl *Property = E->getExplicitProperty();
1130 S = Property->getGetterName();
1131 method = Property->getGetterMethodDecl();
1133 method = E->getImplicitPropertyGetter();
1134 S = method->getSelector();
1137 llvm::Value *Receiver = LV.getPropertyRefBaseAddr();
1139 if (CGM.getLangOptions().ObjCAutoRefCount) {
1140 QualType receiverType;
1141 if (E->isSuperReceiver())
1142 receiverType = E->getSuperReceiverType();
1143 else if (E->isClassReceiver())
1144 receiverType = getContext().getObjCClassType();
1146 receiverType = E->getBase()->getType();
1149 // Accesses to 'super' follow a different code path.
1150 if (E->isSuperReceiver())
1151 return AdjustRelatedResultType(*this, E, method,
1152 GenerateMessageSendSuper(*this, Return,
1156 const ObjCInterfaceDecl *ReceiverClass
1157 = (E->isClassReceiver() ? E->getClassReceiver() : 0);
1158 return AdjustRelatedResultType(*this, E, method,
1159 CGM.getObjCRuntime().
1160 GenerateMessageSend(*this, Return, ResultType, S,
1161 Receiver, CallArgList(), ReceiverClass));
1164 void CodeGenFunction::EmitStoreThroughPropertyRefLValue(RValue Src,
1166 const ObjCPropertyRefExpr *E = Dst.getPropertyRefExpr();
1167 Selector S = E->getSetterSelector();
1168 QualType ArgType = E->getSetterArgType();
1170 // FIXME. Other than scalars, AST is not adequate for setter and
1171 // getter type mismatches which require conversion.
1172 if (Src.isScalar()) {
1173 llvm::Value *SrcVal = Src.getScalarVal();
1174 QualType DstType = getContext().getCanonicalType(ArgType);
1175 llvm::Type *DstTy = ConvertType(DstType);
1176 if (SrcVal->getType() != DstTy)
1178 RValue::get(EmitScalarConversion(SrcVal, E->getType(), DstType));
1182 Args.add(Src, ArgType);
1184 llvm::Value *Receiver = Dst.getPropertyRefBaseAddr();
1185 QualType ResultType = getContext().VoidTy;
1187 if (E->isSuperReceiver()) {
1188 GenerateMessageSendSuper(*this, ReturnValueSlot(),
1189 ResultType, S, Receiver, Args);
1193 const ObjCInterfaceDecl *ReceiverClass
1194 = (E->isClassReceiver() ? E->getClassReceiver() : 0);
1196 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
1197 ResultType, S, Receiver, Args,
1201 void CodeGenFunction::EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S){
1202 llvm::Constant *EnumerationMutationFn =
1203 CGM.getObjCRuntime().EnumerationMutationFunction();
1205 if (!EnumerationMutationFn) {
1206 CGM.ErrorUnsupported(&S, "Obj-C fast enumeration for this runtime");
1210 CGDebugInfo *DI = getDebugInfo();
1212 DI->EmitLexicalBlockStart(Builder, S.getSourceRange().getBegin());
1214 // The local variable comes into scope immediately.
1215 AutoVarEmission variable = AutoVarEmission::invalid();
1216 if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement()))
1217 variable = EmitAutoVarAlloca(*cast<VarDecl>(SD->getSingleDecl()));
1219 JumpDest LoopEnd = getJumpDestInCurrentScope("forcoll.end");
1221 // Fast enumeration state.
1222 QualType StateTy = CGM.getObjCFastEnumerationStateType();
1223 llvm::Value *StatePtr = CreateMemTemp(StateTy, "state.ptr");
1224 EmitNullInitialization(StatePtr, StateTy);
1226 // Number of elements in the items array.
1227 static const unsigned NumItems = 16;
1229 // Fetch the countByEnumeratingWithState:objects:count: selector.
1230 IdentifierInfo *II[] = {
1231 &CGM.getContext().Idents.get("countByEnumeratingWithState"),
1232 &CGM.getContext().Idents.get("objects"),
1233 &CGM.getContext().Idents.get("count")
1235 Selector FastEnumSel =
1236 CGM.getContext().Selectors.getSelector(llvm::array_lengthof(II), &II[0]);
1239 getContext().getConstantArrayType(getContext().getObjCIdType(),
1240 llvm::APInt(32, NumItems),
1241 ArrayType::Normal, 0);
1242 llvm::Value *ItemsPtr = CreateMemTemp(ItemsTy, "items.ptr");
1244 // Emit the collection pointer. In ARC, we do a retain.
1245 llvm::Value *Collection;
1246 if (getLangOptions().ObjCAutoRefCount) {
1247 Collection = EmitARCRetainScalarExpr(S.getCollection());
1249 // Enter a cleanup to do the release.
1250 EmitObjCConsumeObject(S.getCollection()->getType(), Collection);
1252 Collection = EmitScalarExpr(S.getCollection());
1255 // The 'continue' label needs to appear within the cleanup for the
1256 // collection object.
1257 JumpDest AfterBody = getJumpDestInCurrentScope("forcoll.next");
1259 // Send it our message:
1262 // The first argument is a temporary of the enumeration-state type.
1263 Args.add(RValue::get(StatePtr), getContext().getPointerType(StateTy));
1265 // The second argument is a temporary array with space for NumItems
1266 // pointers. We'll actually be loading elements from the array
1267 // pointer written into the control state; this buffer is so that
1268 // collections that *aren't* backed by arrays can still queue up
1269 // batches of elements.
1270 Args.add(RValue::get(ItemsPtr), getContext().getPointerType(ItemsTy));
1272 // The third argument is the capacity of that temporary array.
1273 llvm::Type *UnsignedLongLTy = ConvertType(getContext().UnsignedLongTy);
1274 llvm::Constant *Count = llvm::ConstantInt::get(UnsignedLongLTy, NumItems);
1275 Args.add(RValue::get(Count), getContext().UnsignedLongTy);
1277 // Start the enumeration.
1279 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
1280 getContext().UnsignedLongTy,
1284 // The initial number of objects that were returned in the buffer.
1285 llvm::Value *initialBufferLimit = CountRV.getScalarVal();
1287 llvm::BasicBlock *EmptyBB = createBasicBlock("forcoll.empty");
1288 llvm::BasicBlock *LoopInitBB = createBasicBlock("forcoll.loopinit");
1290 llvm::Value *zero = llvm::Constant::getNullValue(UnsignedLongLTy);
1292 // If the limit pointer was zero to begin with, the collection is
1293 // empty; skip all this.
1294 Builder.CreateCondBr(Builder.CreateICmpEQ(initialBufferLimit, zero, "iszero"),
1295 EmptyBB, LoopInitBB);
1297 // Otherwise, initialize the loop.
1298 EmitBlock(LoopInitBB);
1300 // Save the initial mutations value. This is the value at an
1301 // address that was written into the state object by
1302 // countByEnumeratingWithState:objects:count:.
1303 llvm::Value *StateMutationsPtrPtr =
1304 Builder.CreateStructGEP(StatePtr, 2, "mutationsptr.ptr");
1305 llvm::Value *StateMutationsPtr = Builder.CreateLoad(StateMutationsPtrPtr,
1308 llvm::Value *initialMutations =
1309 Builder.CreateLoad(StateMutationsPtr, "forcoll.initial-mutations");
1311 // Start looping. This is the point we return to whenever we have a
1312 // fresh, non-empty batch of objects.
1313 llvm::BasicBlock *LoopBodyBB = createBasicBlock("forcoll.loopbody");
1314 EmitBlock(LoopBodyBB);
1316 // The current index into the buffer.
1317 llvm::PHINode *index = Builder.CreatePHI(UnsignedLongLTy, 3, "forcoll.index");
1318 index->addIncoming(zero, LoopInitBB);
1320 // The current buffer size.
1321 llvm::PHINode *count = Builder.CreatePHI(UnsignedLongLTy, 3, "forcoll.count");
1322 count->addIncoming(initialBufferLimit, LoopInitBB);
1324 // Check whether the mutations value has changed from where it was
1325 // at start. StateMutationsPtr should actually be invariant between
1327 StateMutationsPtr = Builder.CreateLoad(StateMutationsPtrPtr, "mutationsptr");
1328 llvm::Value *currentMutations
1329 = Builder.CreateLoad(StateMutationsPtr, "statemutations");
1331 llvm::BasicBlock *WasMutatedBB = createBasicBlock("forcoll.mutated");
1332 llvm::BasicBlock *WasNotMutatedBB = createBasicBlock("forcoll.notmutated");
1334 Builder.CreateCondBr(Builder.CreateICmpEQ(currentMutations, initialMutations),
1335 WasNotMutatedBB, WasMutatedBB);
1337 // If so, call the enumeration-mutation function.
1338 EmitBlock(WasMutatedBB);
1340 Builder.CreateBitCast(Collection,
1341 ConvertType(getContext().getObjCIdType()));
1343 Args2.add(RValue::get(V), getContext().getObjCIdType());
1344 // FIXME: We shouldn't need to get the function info here, the runtime already
1345 // should have computed it to build the function.
1346 EmitCall(CGM.getTypes().getFunctionInfo(getContext().VoidTy, Args2,
1347 FunctionType::ExtInfo()),
1348 EnumerationMutationFn, ReturnValueSlot(), Args2);
1350 // Otherwise, or if the mutation function returns, just continue.
1351 EmitBlock(WasNotMutatedBB);
1353 // Initialize the element variable.
1354 RunCleanupsScope elementVariableScope(*this);
1355 bool elementIsVariable;
1356 LValue elementLValue;
1357 QualType elementType;
1358 if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement())) {
1359 // Initialize the variable, in case it's a __block variable or something.
1360 EmitAutoVarInit(variable);
1362 const VarDecl* D = cast<VarDecl>(SD->getSingleDecl());
1363 DeclRefExpr tempDRE(const_cast<VarDecl*>(D), D->getType(),
1364 VK_LValue, SourceLocation());
1365 elementLValue = EmitLValue(&tempDRE);
1366 elementType = D->getType();
1367 elementIsVariable = true;
1369 if (D->isARCPseudoStrong())
1370 elementLValue.getQuals().setObjCLifetime(Qualifiers::OCL_ExplicitNone);
1372 elementLValue = LValue(); // suppress warning
1373 elementType = cast<Expr>(S.getElement())->getType();
1374 elementIsVariable = false;
1376 llvm::Type *convertedElementType = ConvertType(elementType);
1378 // Fetch the buffer out of the enumeration state.
1379 // TODO: this pointer should actually be invariant between
1380 // refreshes, which would help us do certain loop optimizations.
1381 llvm::Value *StateItemsPtr =
1382 Builder.CreateStructGEP(StatePtr, 1, "stateitems.ptr");
1383 llvm::Value *EnumStateItems =
1384 Builder.CreateLoad(StateItemsPtr, "stateitems");
1386 // Fetch the value at the current index from the buffer.
1387 llvm::Value *CurrentItemPtr =
1388 Builder.CreateGEP(EnumStateItems, index, "currentitem.ptr");
1389 llvm::Value *CurrentItem = Builder.CreateLoad(CurrentItemPtr);
1391 // Cast that value to the right type.
1392 CurrentItem = Builder.CreateBitCast(CurrentItem, convertedElementType,
1395 // Make sure we have an l-value. Yes, this gets evaluated every
1396 // time through the loop.
1397 if (!elementIsVariable) {
1398 elementLValue = EmitLValue(cast<Expr>(S.getElement()));
1399 EmitStoreThroughLValue(RValue::get(CurrentItem), elementLValue);
1401 EmitScalarInit(CurrentItem, elementLValue);
1404 // If we do have an element variable, this assignment is the end of
1405 // its initialization.
1406 if (elementIsVariable)
1407 EmitAutoVarCleanups(variable);
1409 // Perform the loop body, setting up break and continue labels.
1410 BreakContinueStack.push_back(BreakContinue(LoopEnd, AfterBody));
1412 RunCleanupsScope Scope(*this);
1413 EmitStmt(S.getBody());
1415 BreakContinueStack.pop_back();
1417 // Destroy the element variable now.
1418 elementVariableScope.ForceCleanup();
1420 // Check whether there are more elements.
1421 EmitBlock(AfterBody.getBlock());
1423 llvm::BasicBlock *FetchMoreBB = createBasicBlock("forcoll.refetch");
1425 // First we check in the local buffer.
1426 llvm::Value *indexPlusOne
1427 = Builder.CreateAdd(index, llvm::ConstantInt::get(UnsignedLongLTy, 1));
1429 // If we haven't overrun the buffer yet, we can continue.
1430 Builder.CreateCondBr(Builder.CreateICmpULT(indexPlusOne, count),
1431 LoopBodyBB, FetchMoreBB);
1433 index->addIncoming(indexPlusOne, AfterBody.getBlock());
1434 count->addIncoming(count, AfterBody.getBlock());
1436 // Otherwise, we have to fetch more elements.
1437 EmitBlock(FetchMoreBB);
1440 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
1441 getContext().UnsignedLongTy,
1445 // If we got a zero count, we're done.
1446 llvm::Value *refetchCount = CountRV.getScalarVal();
1448 // (note that the message send might split FetchMoreBB)
1449 index->addIncoming(zero, Builder.GetInsertBlock());
1450 count->addIncoming(refetchCount, Builder.GetInsertBlock());
1452 Builder.CreateCondBr(Builder.CreateICmpEQ(refetchCount, zero),
1453 EmptyBB, LoopBodyBB);
1455 // No more elements.
1458 if (!elementIsVariable) {
1459 // If the element was not a declaration, set it to be null.
1461 llvm::Value *null = llvm::Constant::getNullValue(convertedElementType);
1462 elementLValue = EmitLValue(cast<Expr>(S.getElement()));
1463 EmitStoreThroughLValue(RValue::get(null), elementLValue);
1467 DI->EmitLexicalBlockEnd(Builder, S.getSourceRange().getEnd());
1469 // Leave the cleanup we entered in ARC.
1470 if (getLangOptions().ObjCAutoRefCount)
1473 EmitBlock(LoopEnd.getBlock());
1476 void CodeGenFunction::EmitObjCAtTryStmt(const ObjCAtTryStmt &S) {
1477 CGM.getObjCRuntime().EmitTryStmt(*this, S);
1480 void CodeGenFunction::EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S) {
1481 CGM.getObjCRuntime().EmitThrowStmt(*this, S);
1484 void CodeGenFunction::EmitObjCAtSynchronizedStmt(
1485 const ObjCAtSynchronizedStmt &S) {
1486 CGM.getObjCRuntime().EmitSynchronizedStmt(*this, S);
1489 /// Produce the code for a CK_ARCProduceObject. Just does a
1490 /// primitive retain.
1491 llvm::Value *CodeGenFunction::EmitObjCProduceObject(QualType type,
1492 llvm::Value *value) {
1493 return EmitARCRetain(type, value);
1497 struct CallObjCRelease : EHScopeStack::Cleanup {
1498 CallObjCRelease(llvm::Value *object) : object(object) {}
1499 llvm::Value *object;
1501 void Emit(CodeGenFunction &CGF, Flags flags) {
1502 CGF.EmitARCRelease(object, /*precise*/ true);
1507 /// Produce the code for a CK_ARCConsumeObject. Does a primitive
1508 /// release at the end of the full-expression.
1509 llvm::Value *CodeGenFunction::EmitObjCConsumeObject(QualType type,
1510 llvm::Value *object) {
1511 // If we're in a conditional branch, we need to make the cleanup
1513 pushFullExprCleanup<CallObjCRelease>(getARCCleanupKind(), object);
1517 llvm::Value *CodeGenFunction::EmitObjCExtendObjectLifetime(QualType type,
1518 llvm::Value *value) {
1519 return EmitARCRetainAutorelease(type, value);
1523 static llvm::Constant *createARCRuntimeFunction(CodeGenModule &CGM,
1524 llvm::FunctionType *type,
1526 llvm::Constant *fn = CGM.CreateRuntimeFunction(type, fnName);
1528 // In -fobjc-no-arc-runtime, emit weak references to the runtime
1530 if (!CGM.getCodeGenOpts().ObjCRuntimeHasARC)
1531 if (llvm::Function *f = dyn_cast<llvm::Function>(fn))
1532 f->setLinkage(llvm::Function::ExternalWeakLinkage);
1537 /// Perform an operation having the signature
1539 /// where a null input causes a no-op and returns null.
1540 static llvm::Value *emitARCValueOperation(CodeGenFunction &CGF,
1542 llvm::Constant *&fn,
1544 if (isa<llvm::ConstantPointerNull>(value)) return value;
1547 std::vector<llvm::Type*> args(1, CGF.Int8PtrTy);
1548 llvm::FunctionType *fnType =
1549 llvm::FunctionType::get(CGF.Int8PtrTy, args, false);
1550 fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName);
1553 // Cast the argument to 'id'.
1554 llvm::Type *origType = value->getType();
1555 value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy);
1557 // Call the function.
1558 llvm::CallInst *call = CGF.Builder.CreateCall(fn, value);
1559 call->setDoesNotThrow();
1561 // Cast the result back to the original type.
1562 return CGF.Builder.CreateBitCast(call, origType);
1565 /// Perform an operation having the following signature:
1567 static llvm::Value *emitARCLoadOperation(CodeGenFunction &CGF,
1569 llvm::Constant *&fn,
1572 std::vector<llvm::Type*> args(1, CGF.Int8PtrPtrTy);
1573 llvm::FunctionType *fnType =
1574 llvm::FunctionType::get(CGF.Int8PtrTy, args, false);
1575 fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName);
1578 // Cast the argument to 'id*'.
1579 llvm::Type *origType = addr->getType();
1580 addr = CGF.Builder.CreateBitCast(addr, CGF.Int8PtrPtrTy);
1582 // Call the function.
1583 llvm::CallInst *call = CGF.Builder.CreateCall(fn, addr);
1584 call->setDoesNotThrow();
1586 // Cast the result back to a dereference of the original type.
1587 llvm::Value *result = call;
1588 if (origType != CGF.Int8PtrPtrTy)
1589 result = CGF.Builder.CreateBitCast(result,
1590 cast<llvm::PointerType>(origType)->getElementType());
1595 /// Perform an operation having the following signature:
1597 static llvm::Value *emitARCStoreOperation(CodeGenFunction &CGF,
1600 llvm::Constant *&fn,
1603 assert(cast<llvm::PointerType>(addr->getType())->getElementType()
1604 == value->getType());
1607 std::vector<llvm::Type*> argTypes(2);
1608 argTypes[0] = CGF.Int8PtrPtrTy;
1609 argTypes[1] = CGF.Int8PtrTy;
1611 llvm::FunctionType *fnType
1612 = llvm::FunctionType::get(CGF.Int8PtrTy, argTypes, false);
1613 fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName);
1616 llvm::Type *origType = value->getType();
1618 addr = CGF.Builder.CreateBitCast(addr, CGF.Int8PtrPtrTy);
1619 value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy);
1621 llvm::CallInst *result = CGF.Builder.CreateCall2(fn, addr, value);
1622 result->setDoesNotThrow();
1624 if (ignored) return 0;
1626 return CGF.Builder.CreateBitCast(result, origType);
1629 /// Perform an operation having the following signature:
1630 /// void (i8**, i8**)
1631 static void emitARCCopyOperation(CodeGenFunction &CGF,
1634 llvm::Constant *&fn,
1636 assert(dst->getType() == src->getType());
1639 std::vector<llvm::Type*> argTypes(2, CGF.Int8PtrPtrTy);
1640 llvm::FunctionType *fnType
1641 = llvm::FunctionType::get(CGF.Builder.getVoidTy(), argTypes, false);
1642 fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName);
1645 dst = CGF.Builder.CreateBitCast(dst, CGF.Int8PtrPtrTy);
1646 src = CGF.Builder.CreateBitCast(src, CGF.Int8PtrPtrTy);
1648 llvm::CallInst *result = CGF.Builder.CreateCall2(fn, dst, src);
1649 result->setDoesNotThrow();
1652 /// Produce the code to do a retain. Based on the type, calls one of:
1653 /// call i8* @objc_retain(i8* %value)
1654 /// call i8* @objc_retainBlock(i8* %value)
1655 llvm::Value *CodeGenFunction::EmitARCRetain(QualType type, llvm::Value *value) {
1656 if (type->isBlockPointerType())
1657 return EmitARCRetainBlock(value, /*mandatory*/ false);
1659 return EmitARCRetainNonBlock(value);
1662 /// Retain the given object, with normal retain semantics.
1663 /// call i8* @objc_retain(i8* %value)
1664 llvm::Value *CodeGenFunction::EmitARCRetainNonBlock(llvm::Value *value) {
1665 return emitARCValueOperation(*this, value,
1666 CGM.getARCEntrypoints().objc_retain,
1670 /// Retain the given block, with _Block_copy semantics.
1671 /// call i8* @objc_retainBlock(i8* %value)
1673 /// \param mandatory - If false, emit the call with metadata
1674 /// indicating that it's okay for the optimizer to eliminate this call
1675 /// if it can prove that the block never escapes except down the stack.
1676 llvm::Value *CodeGenFunction::EmitARCRetainBlock(llvm::Value *value,
1679 = emitARCValueOperation(*this, value,
1680 CGM.getARCEntrypoints().objc_retainBlock,
1681 "objc_retainBlock");
1683 // If the copy isn't mandatory, add !clang.arc.copy_on_escape to
1684 // tell the optimizer that it doesn't need to do this copy if the
1685 // block doesn't escape, where being passed as an argument doesn't
1686 // count as escaping.
1687 if (!mandatory && isa<llvm::Instruction>(result)) {
1688 llvm::CallInst *call
1689 = cast<llvm::CallInst>(result->stripPointerCasts());
1690 assert(call->getCalledValue() == CGM.getARCEntrypoints().objc_retainBlock);
1692 SmallVector<llvm::Value*,1> args;
1693 call->setMetadata("clang.arc.copy_on_escape",
1694 llvm::MDNode::get(Builder.getContext(), args));
1700 /// Retain the given object which is the result of a function call.
1701 /// call i8* @objc_retainAutoreleasedReturnValue(i8* %value)
1703 /// Yes, this function name is one character away from a different
1704 /// call with completely different semantics.
1706 CodeGenFunction::EmitARCRetainAutoreleasedReturnValue(llvm::Value *value) {
1707 // Fetch the void(void) inline asm which marks that we're going to
1708 // retain the autoreleased return value.
1709 llvm::InlineAsm *&marker
1710 = CGM.getARCEntrypoints().retainAutoreleasedReturnValueMarker;
1713 = CGM.getTargetCodeGenInfo()
1714 .getARCRetainAutoreleasedReturnValueMarker();
1716 // If we have an empty assembly string, there's nothing to do.
1717 if (assembly.empty()) {
1719 // Otherwise, at -O0, build an inline asm that we're going to call
1721 } else if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
1722 llvm::FunctionType *type =
1723 llvm::FunctionType::get(llvm::Type::getVoidTy(getLLVMContext()),
1724 /*variadic*/ false);
1726 marker = llvm::InlineAsm::get(type, assembly, "", /*sideeffects*/ true);
1728 // If we're at -O1 and above, we don't want to litter the code
1729 // with this marker yet, so leave a breadcrumb for the ARC
1730 // optimizer to pick up.
1732 llvm::NamedMDNode *metadata =
1733 CGM.getModule().getOrInsertNamedMetadata(
1734 "clang.arc.retainAutoreleasedReturnValueMarker");
1735 assert(metadata->getNumOperands() <= 1);
1736 if (metadata->getNumOperands() == 0) {
1737 llvm::Value *string = llvm::MDString::get(getLLVMContext(), assembly);
1738 metadata->addOperand(llvm::MDNode::get(getLLVMContext(), string));
1743 // Call the marker asm if we made one, which we do only at -O0.
1744 if (marker) Builder.CreateCall(marker);
1746 return emitARCValueOperation(*this, value,
1747 CGM.getARCEntrypoints().objc_retainAutoreleasedReturnValue,
1748 "objc_retainAutoreleasedReturnValue");
1751 /// Release the given object.
1752 /// call void @objc_release(i8* %value)
1753 void CodeGenFunction::EmitARCRelease(llvm::Value *value, bool precise) {
1754 if (isa<llvm::ConstantPointerNull>(value)) return;
1756 llvm::Constant *&fn = CGM.getARCEntrypoints().objc_release;
1758 std::vector<llvm::Type*> args(1, Int8PtrTy);
1759 llvm::FunctionType *fnType =
1760 llvm::FunctionType::get(Builder.getVoidTy(), args, false);
1761 fn = createARCRuntimeFunction(CGM, fnType, "objc_release");
1764 // Cast the argument to 'id'.
1765 value = Builder.CreateBitCast(value, Int8PtrTy);
1767 // Call objc_release.
1768 llvm::CallInst *call = Builder.CreateCall(fn, value);
1769 call->setDoesNotThrow();
1772 SmallVector<llvm::Value*,1> args;
1773 call->setMetadata("clang.imprecise_release",
1774 llvm::MDNode::get(Builder.getContext(), args));
1778 /// Store into a strong object. Always calls this:
1779 /// call void @objc_storeStrong(i8** %addr, i8* %value)
1780 llvm::Value *CodeGenFunction::EmitARCStoreStrongCall(llvm::Value *addr,
1783 assert(cast<llvm::PointerType>(addr->getType())->getElementType()
1784 == value->getType());
1786 llvm::Constant *&fn = CGM.getARCEntrypoints().objc_storeStrong;
1788 llvm::Type *argTypes[] = { Int8PtrPtrTy, Int8PtrTy };
1789 llvm::FunctionType *fnType
1790 = llvm::FunctionType::get(Builder.getVoidTy(), argTypes, false);
1791 fn = createARCRuntimeFunction(CGM, fnType, "objc_storeStrong");
1794 addr = Builder.CreateBitCast(addr, Int8PtrPtrTy);
1795 llvm::Value *castValue = Builder.CreateBitCast(value, Int8PtrTy);
1797 Builder.CreateCall2(fn, addr, castValue)->setDoesNotThrow();
1799 if (ignored) return 0;
1803 /// Store into a strong object. Sometimes calls this:
1804 /// call void @objc_storeStrong(i8** %addr, i8* %value)
1805 /// Other times, breaks it down into components.
1806 llvm::Value *CodeGenFunction::EmitARCStoreStrong(LValue dst,
1807 llvm::Value *newValue,
1809 QualType type = dst.getType();
1810 bool isBlock = type->isBlockPointerType();
1812 // Use a store barrier at -O0 unless this is a block type or the
1813 // lvalue is inadequately aligned.
1814 if (shouldUseFusedARCCalls() &&
1816 !(dst.getAlignment() && dst.getAlignment() < PointerAlignInBytes)) {
1817 return EmitARCStoreStrongCall(dst.getAddress(), newValue, ignored);
1820 // Otherwise, split it out.
1822 // Retain the new value.
1823 newValue = EmitARCRetain(type, newValue);
1825 // Read the old value.
1826 llvm::Value *oldValue = EmitLoadOfScalar(dst);
1828 // Store. We do this before the release so that any deallocs won't
1829 // see the old value.
1830 EmitStoreOfScalar(newValue, dst);
1832 // Finally, release the old value.
1833 EmitARCRelease(oldValue, /*precise*/ false);
1838 /// Autorelease the given object.
1839 /// call i8* @objc_autorelease(i8* %value)
1840 llvm::Value *CodeGenFunction::EmitARCAutorelease(llvm::Value *value) {
1841 return emitARCValueOperation(*this, value,
1842 CGM.getARCEntrypoints().objc_autorelease,
1843 "objc_autorelease");
1846 /// Autorelease the given object.
1847 /// call i8* @objc_autoreleaseReturnValue(i8* %value)
1849 CodeGenFunction::EmitARCAutoreleaseReturnValue(llvm::Value *value) {
1850 return emitARCValueOperation(*this, value,
1851 CGM.getARCEntrypoints().objc_autoreleaseReturnValue,
1852 "objc_autoreleaseReturnValue");
1855 /// Do a fused retain/autorelease of the given object.
1856 /// call i8* @objc_retainAutoreleaseReturnValue(i8* %value)
1858 CodeGenFunction::EmitARCRetainAutoreleaseReturnValue(llvm::Value *value) {
1859 return emitARCValueOperation(*this, value,
1860 CGM.getARCEntrypoints().objc_retainAutoreleaseReturnValue,
1861 "objc_retainAutoreleaseReturnValue");
1864 /// Do a fused retain/autorelease of the given object.
1865 /// call i8* @objc_retainAutorelease(i8* %value)
1867 /// %retain = call i8* @objc_retainBlock(i8* %value)
1868 /// call i8* @objc_autorelease(i8* %retain)
1869 llvm::Value *CodeGenFunction::EmitARCRetainAutorelease(QualType type,
1870 llvm::Value *value) {
1871 if (!type->isBlockPointerType())
1872 return EmitARCRetainAutoreleaseNonBlock(value);
1874 if (isa<llvm::ConstantPointerNull>(value)) return value;
1876 llvm::Type *origType = value->getType();
1877 value = Builder.CreateBitCast(value, Int8PtrTy);
1878 value = EmitARCRetainBlock(value, /*mandatory*/ true);
1879 value = EmitARCAutorelease(value);
1880 return Builder.CreateBitCast(value, origType);
1883 /// Do a fused retain/autorelease of the given object.
1884 /// call i8* @objc_retainAutorelease(i8* %value)
1886 CodeGenFunction::EmitARCRetainAutoreleaseNonBlock(llvm::Value *value) {
1887 return emitARCValueOperation(*this, value,
1888 CGM.getARCEntrypoints().objc_retainAutorelease,
1889 "objc_retainAutorelease");
1892 /// i8* @objc_loadWeak(i8** %addr)
1893 /// Essentially objc_autorelease(objc_loadWeakRetained(addr)).
1894 llvm::Value *CodeGenFunction::EmitARCLoadWeak(llvm::Value *addr) {
1895 return emitARCLoadOperation(*this, addr,
1896 CGM.getARCEntrypoints().objc_loadWeak,
1900 /// i8* @objc_loadWeakRetained(i8** %addr)
1901 llvm::Value *CodeGenFunction::EmitARCLoadWeakRetained(llvm::Value *addr) {
1902 return emitARCLoadOperation(*this, addr,
1903 CGM.getARCEntrypoints().objc_loadWeakRetained,
1904 "objc_loadWeakRetained");
1907 /// i8* @objc_storeWeak(i8** %addr, i8* %value)
1909 llvm::Value *CodeGenFunction::EmitARCStoreWeak(llvm::Value *addr,
1912 return emitARCStoreOperation(*this, addr, value,
1913 CGM.getARCEntrypoints().objc_storeWeak,
1914 "objc_storeWeak", ignored);
1917 /// i8* @objc_initWeak(i8** %addr, i8* %value)
1918 /// Returns %value. %addr is known to not have a current weak entry.
1919 /// Essentially equivalent to:
1920 /// *addr = nil; objc_storeWeak(addr, value);
1921 void CodeGenFunction::EmitARCInitWeak(llvm::Value *addr, llvm::Value *value) {
1922 // If we're initializing to null, just write null to memory; no need
1923 // to get the runtime involved. But don't do this if optimization
1924 // is enabled, because accounting for this would make the optimizer
1925 // much more complicated.
1926 if (isa<llvm::ConstantPointerNull>(value) &&
1927 CGM.getCodeGenOpts().OptimizationLevel == 0) {
1928 Builder.CreateStore(value, addr);
1932 emitARCStoreOperation(*this, addr, value,
1933 CGM.getARCEntrypoints().objc_initWeak,
1934 "objc_initWeak", /*ignored*/ true);
1937 /// void @objc_destroyWeak(i8** %addr)
1938 /// Essentially objc_storeWeak(addr, nil).
1939 void CodeGenFunction::EmitARCDestroyWeak(llvm::Value *addr) {
1940 llvm::Constant *&fn = CGM.getARCEntrypoints().objc_destroyWeak;
1942 std::vector<llvm::Type*> args(1, Int8PtrPtrTy);
1943 llvm::FunctionType *fnType =
1944 llvm::FunctionType::get(Builder.getVoidTy(), args, false);
1945 fn = createARCRuntimeFunction(CGM, fnType, "objc_destroyWeak");
1948 // Cast the argument to 'id*'.
1949 addr = Builder.CreateBitCast(addr, Int8PtrPtrTy);
1951 llvm::CallInst *call = Builder.CreateCall(fn, addr);
1952 call->setDoesNotThrow();
1955 /// void @objc_moveWeak(i8** %dest, i8** %src)
1956 /// Disregards the current value in %dest. Leaves %src pointing to nothing.
1957 /// Essentially (objc_copyWeak(dest, src), objc_destroyWeak(src)).
1958 void CodeGenFunction::EmitARCMoveWeak(llvm::Value *dst, llvm::Value *src) {
1959 emitARCCopyOperation(*this, dst, src,
1960 CGM.getARCEntrypoints().objc_moveWeak,
1964 /// void @objc_copyWeak(i8** %dest, i8** %src)
1965 /// Disregards the current value in %dest. Essentially
1966 /// objc_release(objc_initWeak(dest, objc_readWeakRetained(src)))
1967 void CodeGenFunction::EmitARCCopyWeak(llvm::Value *dst, llvm::Value *src) {
1968 emitARCCopyOperation(*this, dst, src,
1969 CGM.getARCEntrypoints().objc_copyWeak,
1973 /// Produce the code to do a objc_autoreleasepool_push.
1974 /// call i8* @objc_autoreleasePoolPush(void)
1975 llvm::Value *CodeGenFunction::EmitObjCAutoreleasePoolPush() {
1976 llvm::Constant *&fn = CGM.getRREntrypoints().objc_autoreleasePoolPush;
1978 llvm::FunctionType *fnType =
1979 llvm::FunctionType::get(Int8PtrTy, false);
1980 fn = createARCRuntimeFunction(CGM, fnType, "objc_autoreleasePoolPush");
1983 llvm::CallInst *call = Builder.CreateCall(fn);
1984 call->setDoesNotThrow();
1989 /// Produce the code to do a primitive release.
1990 /// call void @objc_autoreleasePoolPop(i8* %ptr)
1991 void CodeGenFunction::EmitObjCAutoreleasePoolPop(llvm::Value *value) {
1992 assert(value->getType() == Int8PtrTy);
1994 llvm::Constant *&fn = CGM.getRREntrypoints().objc_autoreleasePoolPop;
1996 std::vector<llvm::Type*> args(1, Int8PtrTy);
1997 llvm::FunctionType *fnType =
1998 llvm::FunctionType::get(Builder.getVoidTy(), args, false);
2000 // We don't want to use a weak import here; instead we should not
2001 // fall into this path.
2002 fn = createARCRuntimeFunction(CGM, fnType, "objc_autoreleasePoolPop");
2005 llvm::CallInst *call = Builder.CreateCall(fn, value);
2006 call->setDoesNotThrow();
2009 /// Produce the code to do an MRR version objc_autoreleasepool_push.
2010 /// Which is: [[NSAutoreleasePool alloc] init];
2011 /// Where alloc is declared as: + (id) alloc; in NSAutoreleasePool class.
2012 /// init is declared as: - (id) init; in its NSObject super class.
2014 llvm::Value *CodeGenFunction::EmitObjCMRRAutoreleasePoolPush() {
2015 CGObjCRuntime &Runtime = CGM.getObjCRuntime();
2016 llvm::Value *Receiver = Runtime.EmitNSAutoreleasePoolClassRef(Builder);
2017 // [NSAutoreleasePool alloc]
2018 IdentifierInfo *II = &CGM.getContext().Idents.get("alloc");
2019 Selector AllocSel = getContext().Selectors.getSelector(0, &II);
2022 Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
2023 getContext().getObjCIdType(),
2024 AllocSel, Receiver, Args);
2027 Receiver = AllocRV.getScalarVal();
2028 II = &CGM.getContext().Idents.get("init");
2029 Selector InitSel = getContext().Selectors.getSelector(0, &II);
2031 Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
2032 getContext().getObjCIdType(),
2033 InitSel, Receiver, Args);
2034 return InitRV.getScalarVal();
2037 /// Produce the code to do a primitive release.
2039 void CodeGenFunction::EmitObjCMRRAutoreleasePoolPop(llvm::Value *Arg) {
2040 IdentifierInfo *II = &CGM.getContext().Idents.get("drain");
2041 Selector DrainSel = getContext().Selectors.getSelector(0, &II);
2043 CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
2044 getContext().VoidTy, DrainSel, Arg, Args);
2047 void CodeGenFunction::destroyARCStrongPrecise(CodeGenFunction &CGF,
2050 llvm::Value *ptr = CGF.Builder.CreateLoad(addr, "strongdestroy");
2051 CGF.EmitARCRelease(ptr, /*precise*/ true);
2054 void CodeGenFunction::destroyARCStrongImprecise(CodeGenFunction &CGF,
2057 llvm::Value *ptr = CGF.Builder.CreateLoad(addr, "strongdestroy");
2058 CGF.EmitARCRelease(ptr, /*precise*/ false);
2061 void CodeGenFunction::destroyARCWeak(CodeGenFunction &CGF,
2064 CGF.EmitARCDestroyWeak(addr);
2068 struct CallObjCAutoreleasePoolObject : EHScopeStack::Cleanup {
2071 CallObjCAutoreleasePoolObject(llvm::Value *token) : Token(token) {}
2073 void Emit(CodeGenFunction &CGF, Flags flags) {
2074 CGF.EmitObjCAutoreleasePoolPop(Token);
2077 struct CallObjCMRRAutoreleasePoolObject : EHScopeStack::Cleanup {
2080 CallObjCMRRAutoreleasePoolObject(llvm::Value *token) : Token(token) {}
2082 void Emit(CodeGenFunction &CGF, Flags flags) {
2083 CGF.EmitObjCMRRAutoreleasePoolPop(Token);
2088 void CodeGenFunction::EmitObjCAutoreleasePoolCleanup(llvm::Value *Ptr) {
2089 if (CGM.getLangOptions().ObjCAutoRefCount)
2090 EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, Ptr);
2092 EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, Ptr);
2095 static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF,
2098 switch (type.getObjCLifetime()) {
2099 case Qualifiers::OCL_None:
2100 case Qualifiers::OCL_ExplicitNone:
2101 case Qualifiers::OCL_Strong:
2102 case Qualifiers::OCL_Autoreleasing:
2103 return TryEmitResult(CGF.EmitLoadOfLValue(lvalue).getScalarVal(),
2106 case Qualifiers::OCL_Weak:
2107 return TryEmitResult(CGF.EmitARCLoadWeakRetained(lvalue.getAddress()),
2111 llvm_unreachable("impossible lifetime!");
2112 return TryEmitResult();
2115 static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF,
2117 e = e->IgnoreParens();
2118 QualType type = e->getType();
2120 // If we're loading retained from a __strong xvalue, we can avoid
2121 // an extra retain/release pair by zeroing out the source of this
2122 // "move" operation.
2123 if (e->isXValue() &&
2124 !type.isConstQualified() &&
2125 type.getObjCLifetime() == Qualifiers::OCL_Strong) {
2127 LValue lv = CGF.EmitLValue(e);
2129 // Load the object pointer.
2130 llvm::Value *result = CGF.EmitLoadOfLValue(lv).getScalarVal();
2132 // Set the source pointer to NULL.
2133 CGF.EmitStoreOfScalar(getNullForVariable(lv.getAddress()), lv);
2135 return TryEmitResult(result, true);
2138 // As a very special optimization, in ARC++, if the l-value is the
2139 // result of a non-volatile assignment, do a simple retain of the
2140 // result of the call to objc_storeWeak instead of reloading.
2141 if (CGF.getLangOptions().CPlusPlus &&
2142 !type.isVolatileQualified() &&
2143 type.getObjCLifetime() == Qualifiers::OCL_Weak &&
2144 isa<BinaryOperator>(e) &&
2145 cast<BinaryOperator>(e)->getOpcode() == BO_Assign)
2146 return TryEmitResult(CGF.EmitScalarExpr(e), false);
2148 return tryEmitARCRetainLoadOfScalar(CGF, CGF.EmitLValue(e), type);
2151 static llvm::Value *emitARCRetainAfterCall(CodeGenFunction &CGF,
2152 llvm::Value *value);
2154 /// Given that the given expression is some sort of call (which does
2155 /// not return retained), emit a retain following it.
2156 static llvm::Value *emitARCRetainCall(CodeGenFunction &CGF, const Expr *e) {
2157 llvm::Value *value = CGF.EmitScalarExpr(e);
2158 return emitARCRetainAfterCall(CGF, value);
2161 static llvm::Value *emitARCRetainAfterCall(CodeGenFunction &CGF,
2162 llvm::Value *value) {
2163 if (llvm::CallInst *call = dyn_cast<llvm::CallInst>(value)) {
2164 CGBuilderTy::InsertPoint ip = CGF.Builder.saveIP();
2166 // Place the retain immediately following the call.
2167 CGF.Builder.SetInsertPoint(call->getParent(),
2168 ++llvm::BasicBlock::iterator(call));
2169 value = CGF.EmitARCRetainAutoreleasedReturnValue(value);
2171 CGF.Builder.restoreIP(ip);
2173 } else if (llvm::InvokeInst *invoke = dyn_cast<llvm::InvokeInst>(value)) {
2174 CGBuilderTy::InsertPoint ip = CGF.Builder.saveIP();
2176 // Place the retain at the beginning of the normal destination block.
2177 llvm::BasicBlock *BB = invoke->getNormalDest();
2178 CGF.Builder.SetInsertPoint(BB, BB->begin());
2179 value = CGF.EmitARCRetainAutoreleasedReturnValue(value);
2181 CGF.Builder.restoreIP(ip);
2184 // Bitcasts can arise because of related-result returns. Rewrite
2186 } else if (llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(value)) {
2187 llvm::Value *operand = bitcast->getOperand(0);
2188 operand = emitARCRetainAfterCall(CGF, operand);
2189 bitcast->setOperand(0, operand);
2192 // Generic fall-back case.
2194 // Retain using the non-block variant: we never need to do a copy
2195 // of a block that's been returned to us.
2196 return CGF.EmitARCRetainNonBlock(value);
2200 /// Determine whether it might be important to emit a separate
2201 /// objc_retain_block on the result of the given expression, or
2202 /// whether it's okay to just emit it in a +1 context.
2203 static bool shouldEmitSeparateBlockRetain(const Expr *e) {
2204 assert(e->getType()->isBlockPointerType());
2205 e = e->IgnoreParens();
2207 // For future goodness, emit block expressions directly in +1
2208 // contexts if we can.
2209 if (isa<BlockExpr>(e))
2212 if (const CastExpr *cast = dyn_cast<CastExpr>(e)) {
2213 switch (cast->getCastKind()) {
2214 // Emitting these operations in +1 contexts is goodness.
2215 case CK_LValueToRValue:
2216 case CK_ARCReclaimReturnedObject:
2217 case CK_ARCConsumeObject:
2218 case CK_ARCProduceObject:
2221 // These operations preserve a block type.
2224 return shouldEmitSeparateBlockRetain(cast->getSubExpr());
2226 // These operations are known to be bad (or haven't been considered).
2227 case CK_AnyPointerToBlockPointerCast:
2236 static TryEmitResult
2237 tryEmitARCRetainScalarExpr(CodeGenFunction &CGF, const Expr *e) {
2238 // Look through cleanups.
2239 if (const ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(e)) {
2240 CodeGenFunction::RunCleanupsScope scope(CGF);
2241 return tryEmitARCRetainScalarExpr(CGF, cleanups->getSubExpr());
2244 // The desired result type, if it differs from the type of the
2245 // ultimate opaque expression.
2246 llvm::Type *resultType = 0;
2249 e = e->IgnoreParens();
2251 // There's a break at the end of this if-chain; anything
2252 // that wants to keep looping has to explicitly continue.
2253 if (const CastExpr *ce = dyn_cast<CastExpr>(e)) {
2254 switch (ce->getCastKind()) {
2255 // No-op casts don't change the type, so we just ignore them.
2257 e = ce->getSubExpr();
2260 case CK_LValueToRValue: {
2261 TryEmitResult loadResult
2262 = tryEmitARCRetainLoadOfScalar(CGF, ce->getSubExpr());
2264 llvm::Value *value = loadResult.getPointer();
2265 value = CGF.Builder.CreateBitCast(value, resultType);
2266 loadResult.setPointer(value);
2271 // These casts can change the type, so remember that and
2272 // soldier on. We only need to remember the outermost such
2274 case CK_CPointerToObjCPointerCast:
2275 case CK_BlockPointerToObjCPointerCast:
2276 case CK_AnyPointerToBlockPointerCast:
2279 resultType = CGF.ConvertType(ce->getType());
2280 e = ce->getSubExpr();
2281 assert(e->getType()->hasPointerRepresentation());
2284 // For consumptions, just emit the subexpression and thus elide
2285 // the retain/release pair.
2286 case CK_ARCConsumeObject: {
2287 llvm::Value *result = CGF.EmitScalarExpr(ce->getSubExpr());
2288 if (resultType) result = CGF.Builder.CreateBitCast(result, resultType);
2289 return TryEmitResult(result, true);
2292 // Block extends are net +0. Naively, we could just recurse on
2293 // the subexpression, but actually we need to ensure that the
2294 // value is copied as a block, so there's a little filter here.
2295 case CK_ARCExtendBlockObject: {
2296 llvm::Value *result; // will be a +0 value
2298 // If we can't safely assume the sub-expression will produce a
2299 // block-copied value, emit the sub-expression at +0.
2300 if (shouldEmitSeparateBlockRetain(ce->getSubExpr())) {
2301 result = CGF.EmitScalarExpr(ce->getSubExpr());
2303 // Otherwise, try to emit the sub-expression at +1 recursively.
2305 TryEmitResult subresult
2306 = tryEmitARCRetainScalarExpr(CGF, ce->getSubExpr());
2307 result = subresult.getPointer();
2309 // If that produced a retained value, just use that,
2310 // possibly casting down.
2311 if (subresult.getInt()) {
2313 result = CGF.Builder.CreateBitCast(result, resultType);
2314 return TryEmitResult(result, true);
2317 // Otherwise it's +0.
2320 // Retain the object as a block, then cast down.
2321 result = CGF.EmitARCRetainBlock(result, /*mandatory*/ true);
2322 if (resultType) result = CGF.Builder.CreateBitCast(result, resultType);
2323 return TryEmitResult(result, true);
2326 // For reclaims, emit the subexpression as a retained call and
2327 // skip the consumption.
2328 case CK_ARCReclaimReturnedObject: {
2329 llvm::Value *result = emitARCRetainCall(CGF, ce->getSubExpr());
2330 if (resultType) result = CGF.Builder.CreateBitCast(result, resultType);
2331 return TryEmitResult(result, true);
2334 case CK_GetObjCProperty: {
2335 llvm::Value *result = emitARCRetainCall(CGF, ce);
2336 if (resultType) result = CGF.Builder.CreateBitCast(result, resultType);
2337 return TryEmitResult(result, true);
2344 // Skip __extension__.
2345 } else if (const UnaryOperator *op = dyn_cast<UnaryOperator>(e)) {
2346 if (op->getOpcode() == UO_Extension) {
2347 e = op->getSubExpr();
2351 // For calls and message sends, use the retained-call logic.
2352 // Delegate inits are a special case in that they're the only
2353 // returns-retained expression that *isn't* surrounded by
2355 } else if (isa<CallExpr>(e) ||
2356 (isa<ObjCMessageExpr>(e) &&
2357 !cast<ObjCMessageExpr>(e)->isDelegateInitCall())) {
2358 llvm::Value *result = emitARCRetainCall(CGF, e);
2359 if (resultType) result = CGF.Builder.CreateBitCast(result, resultType);
2360 return TryEmitResult(result, true);
2363 // Conservatively halt the search at any other expression kind.
2367 // We didn't find an obvious production, so emit what we've got and
2368 // tell the caller that we didn't manage to retain.
2369 llvm::Value *result = CGF.EmitScalarExpr(e);
2370 if (resultType) result = CGF.Builder.CreateBitCast(result, resultType);
2371 return TryEmitResult(result, false);
2374 static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF,
2377 TryEmitResult result = tryEmitARCRetainLoadOfScalar(CGF, lvalue, type);
2378 llvm::Value *value = result.getPointer();
2379 if (!result.getInt())
2380 value = CGF.EmitARCRetain(type, value);
2384 /// EmitARCRetainScalarExpr - Semantically equivalent to
2385 /// EmitARCRetainObject(e->getType(), EmitScalarExpr(e)), but making a
2386 /// best-effort attempt to peephole expressions that naturally produce
2387 /// retained objects.
2388 llvm::Value *CodeGenFunction::EmitARCRetainScalarExpr(const Expr *e) {
2389 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e);
2390 llvm::Value *value = result.getPointer();
2391 if (!result.getInt())
2392 value = EmitARCRetain(e->getType(), value);
2397 CodeGenFunction::EmitARCRetainAutoreleaseScalarExpr(const Expr *e) {
2398 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e);
2399 llvm::Value *value = result.getPointer();
2400 if (result.getInt())
2401 value = EmitARCAutorelease(value);
2403 value = EmitARCRetainAutorelease(e->getType(), value);
2407 llvm::Value *CodeGenFunction::EmitARCExtendBlockObject(const Expr *e) {
2408 llvm::Value *result;
2411 if (shouldEmitSeparateBlockRetain(e)) {
2412 result = EmitScalarExpr(e);
2415 TryEmitResult subresult = tryEmitARCRetainScalarExpr(*this, e);
2416 result = subresult.getPointer();
2417 doRetain = !subresult.getInt();
2421 result = EmitARCRetainBlock(result, /*mandatory*/ true);
2422 return EmitObjCConsumeObject(e->getType(), result);
2425 llvm::Value *CodeGenFunction::EmitObjCThrowOperand(const Expr *expr) {
2426 // In ARC, retain and autorelease the expression.
2427 if (getLangOptions().ObjCAutoRefCount) {
2428 // Do so before running any cleanups for the full-expression.
2429 // tryEmitARCRetainScalarExpr does make an effort to do things
2430 // inside cleanups, but there are crazy cases like
2432 // where a full retain+autorelease is required and would
2433 // otherwise happen after the destructor for the temporary.
2434 CodeGenFunction::RunCleanupsScope cleanups(*this);
2435 if (const ExprWithCleanups *ewc = dyn_cast<ExprWithCleanups>(expr))
2436 expr = ewc->getSubExpr();
2438 return EmitARCRetainAutoreleaseScalarExpr(expr);
2441 // Otherwise, use the normal scalar-expression emission. The
2442 // exception machinery doesn't do anything special with the
2443 // exception like retaining it, so there's no safety associated with
2444 // only running cleanups after the throw has started, and when it
2445 // matters it tends to be substantially inferior code.
2446 return EmitScalarExpr(expr);
2449 std::pair<LValue,llvm::Value*>
2450 CodeGenFunction::EmitARCStoreStrong(const BinaryOperator *e,
2452 // Evaluate the RHS first.
2453 TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e->getRHS());
2454 llvm::Value *value = result.getPointer();
2456 bool hasImmediateRetain = result.getInt();
2458 // If we didn't emit a retained object, and the l-value is of block
2459 // type, then we need to emit the block-retain immediately in case
2460 // it invalidates the l-value.
2461 if (!hasImmediateRetain && e->getType()->isBlockPointerType()) {
2462 value = EmitARCRetainBlock(value, /*mandatory*/ false);
2463 hasImmediateRetain = true;
2466 LValue lvalue = EmitLValue(e->getLHS());
2468 // If the RHS was emitted retained, expand this.
2469 if (hasImmediateRetain) {
2470 llvm::Value *oldValue =
2471 EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatileQualified(),
2472 lvalue.getAlignment(), e->getType(),
2473 lvalue.getTBAAInfo());
2474 EmitStoreOfScalar(value, lvalue.getAddress(),
2475 lvalue.isVolatileQualified(), lvalue.getAlignment(),
2476 e->getType(), lvalue.getTBAAInfo());
2477 EmitARCRelease(oldValue, /*precise*/ false);
2479 value = EmitARCStoreStrong(lvalue, value, ignored);
2482 return std::pair<LValue,llvm::Value*>(lvalue, value);
2485 std::pair<LValue,llvm::Value*>
2486 CodeGenFunction::EmitARCStoreAutoreleasing(const BinaryOperator *e) {
2487 llvm::Value *value = EmitARCRetainAutoreleaseScalarExpr(e->getRHS());
2488 LValue lvalue = EmitLValue(e->getLHS());
2490 EmitStoreOfScalar(value, lvalue.getAddress(),
2491 lvalue.isVolatileQualified(), lvalue.getAlignment(),
2492 e->getType(), lvalue.getTBAAInfo());
2494 return std::pair<LValue,llvm::Value*>(lvalue, value);
2497 void CodeGenFunction::EmitObjCAutoreleasePoolStmt(
2498 const ObjCAutoreleasePoolStmt &ARPS) {
2499 const Stmt *subStmt = ARPS.getSubStmt();
2500 const CompoundStmt &S = cast<CompoundStmt>(*subStmt);
2502 CGDebugInfo *DI = getDebugInfo();
2504 DI->EmitLexicalBlockStart(Builder, S.getLBracLoc());
2506 // Keep track of the current cleanup stack depth.
2507 RunCleanupsScope Scope(*this);
2508 if (CGM.getCodeGenOpts().ObjCRuntimeHasARC) {
2509 llvm::Value *token = EmitObjCAutoreleasePoolPush();
2510 EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, token);
2512 llvm::Value *token = EmitObjCMRRAutoreleasePoolPush();
2513 EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, token);
2516 for (CompoundStmt::const_body_iterator I = S.body_begin(),
2517 E = S.body_end(); I != E; ++I)
2521 DI->EmitLexicalBlockEnd(Builder, S.getRBracLoc());
2524 /// EmitExtendGCLifetime - Given a pointer to an Objective-C object,
2525 /// make sure it survives garbage collection until this point.
2526 void CodeGenFunction::EmitExtendGCLifetime(llvm::Value *object) {
2527 // We just use an inline assembly.
2528 llvm::FunctionType *extenderType
2529 = llvm::FunctionType::get(VoidTy, VoidPtrTy, /*variadic*/ false);
2530 llvm::Value *extender
2531 = llvm::InlineAsm::get(extenderType,
2533 /* constraints */ "r",
2534 /* side effects */ true);
2536 object = Builder.CreateBitCast(object, VoidPtrTy);
2537 Builder.CreateCall(extender, object)->setDoesNotThrow();
2540 CGObjCRuntime::~CGObjCRuntime() {}