nicolas/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
Files
35e4f0cd0fc0e7f23b10c597f840639199f99eb0
llvm-project/clang/lib/CodeGen/CGObjC.cpp
John McCall a5efa7386a Track whether an AggValueSlot is potentially aliased, and do not 
emit call results into potentially aliased slots.  This allows us
to properly mark indirect return slots as noalias, at the cost
of requiring an extra memcpy when assigning an aggregate call
result into a l-value.  It also brings us into compliance with
the x86-64 ABI.

llvm-svn: 138599
2011-08-25 23:04:34 +00:00

2200 lines
84 KiB
C++
Raw Blame History

//===---- CGBuiltin.cpp - Emit LLVM Code for builtins ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This contains code to emit Objective-C code as LLVM code.
//
//===----------------------------------------------------------------------===//
#include "CGDebugInfo.h"
#include "CGObjCRuntime.h"
#include "CodeGenFunction.h"
#include "CodeGenModule.h"
#include "TargetInfo.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/StmtObjC.h"
#include "clang/Basic/Diagnostic.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Target/TargetData.h"
#include "llvm/InlineAsm.h"
using namespace clang;
using namespace CodeGen;
typedef llvm::PointerIntPair<llvm::Value*,1,bool> TryEmitResult;
static TryEmitResult
tryEmitARCRetainScalarExpr(CodeGenFunction &CGF, const Expr *e);
/// Given the address of a variable of pointer type, find the correct
/// null to store into it.
static llvm::Constant *getNullForVariable(llvm::Value *addr) {
llvm::Type *type =
cast<llvm::PointerType>(addr->getType())->getElementType();
return llvm::ConstantPointerNull::get(cast<llvm::PointerType>(type));
}
/// Emits an instance of NSConstantString representing the object.
llvm::Value *CodeGenFunction::EmitObjCStringLiteral(const ObjCStringLiteral *E)
{
llvm::Constant *C =
CGM.getObjCRuntime().GenerateConstantString(E->getString());
// FIXME: This bitcast should just be made an invariant on the Runtime.
return llvm::ConstantExpr::getBitCast(C, ConvertType(E->getType()));
}
/// Emit a selector.
llvm::Value *CodeGenFunction::EmitObjCSelectorExpr(const ObjCSelectorExpr *E) {
// Untyped selector.
// Note that this implementation allows for non-constant strings to be passed
// as arguments to @selector(). Currently, the only thing preventing this
// behaviour is the type checking in the front end.
return CGM.getObjCRuntime().GetSelector(Builder, E->getSelector());
}
llvm::Value *CodeGenFunction::EmitObjCProtocolExpr(const ObjCProtocolExpr *E) {
// FIXME: This should pass the Decl not the name.
return CGM.getObjCRuntime().GenerateProtocolRef(Builder, E->getProtocol());
}
/// \brief Adjust the type of the result of an Objective-C message send
/// expression when the method has a related result type.
static RValue AdjustRelatedResultType(CodeGenFunction &CGF,
const Expr *E,
const ObjCMethodDecl *Method,
RValue Result) {
if (!Method)
return Result;
if (!Method->hasRelatedResultType() ||
CGF.getContext().hasSameType(E->getType(), Method->getResultType()) ||
!Result.isScalar())
return Result;
// We have applied a related result type. Cast the rvalue appropriately.
return RValue::get(CGF.Builder.CreateBitCast(Result.getScalarVal(),
CGF.ConvertType(E->getType())));
}
/// Decide whether to extend the lifetime of the receiver of a
/// returns-inner-pointer message.
static bool
shouldExtendReceiverForInnerPointerMessage(const ObjCMessageExpr *message) {
switch (message->getReceiverKind()) {
// For a normal instance message, we should extend unless the
// receiver is loaded from a variable with precise lifetime.
case ObjCMessageExpr::Instance: {
const Expr *receiver = message->getInstanceReceiver();
const ImplicitCastExpr *ice = dyn_cast<ImplicitCastExpr>(receiver);
if (!ice || ice->getCastKind() != CK_LValueToRValue) return true;
receiver = ice->getSubExpr()->IgnoreParens();
// Only __strong variables.
if (receiver->getType().getObjCLifetime() != Qualifiers::OCL_Strong)
return true;
// All ivars and fields have precise lifetime.
if (isa<MemberExpr>(receiver) || isa<ObjCIvarRefExpr>(receiver))
return false;
// Otherwise, check for variables.
const DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(ice->getSubExpr());
if (!declRef) return true;
const VarDecl *var = dyn_cast<VarDecl>(declRef->getDecl());
if (!var) return true;
// All variables have precise lifetime except local variables with
// automatic storage duration that aren't specially marked.
return (var->hasLocalStorage() &&
!var->hasAttr<ObjCPreciseLifetimeAttr>());
}
case ObjCMessageExpr::Class:
case ObjCMessageExpr::SuperClass:
// It's never necessary for class objects.
return false;
case ObjCMessageExpr::SuperInstance:
// We generally assume that 'self' lives throughout a method call.
return false;
}
llvm_unreachable("invalid receiver kind");
}
RValue CodeGenFunction::EmitObjCMessageExpr(const ObjCMessageExpr *E,
ReturnValueSlot Return) {
// Only the lookup mechanism and first two arguments of the method
// implementation vary between runtimes. We can get the receiver and
// arguments in generic code.
bool isDelegateInit = E->isDelegateInitCall();
const ObjCMethodDecl *method = E->getMethodDecl();
// We don't retain the receiver in delegate init calls, and this is
// safe because the receiver value is always loaded from 'self',
// which we zero out. We don't want to Block_copy block receivers,
// though.
bool retainSelf =
(!isDelegateInit &&
CGM.getLangOptions().ObjCAutoRefCount &&
method &&
method->hasAttr<NSConsumesSelfAttr>());
CGObjCRuntime &Runtime = CGM.getObjCRuntime();
bool isSuperMessage = false;
bool isClassMessage = false;
ObjCInterfaceDecl *OID = 0;
// Find the receiver
QualType ReceiverType;
llvm::Value *Receiver = 0;
switch (E->getReceiverKind()) {
case ObjCMessageExpr::Instance:
ReceiverType = E->getInstanceReceiver()->getType();
if (retainSelf) {
TryEmitResult ter = tryEmitARCRetainScalarExpr(*this,
E->getInstanceReceiver());
Receiver = ter.getPointer();
if (ter.getInt()) retainSelf = false;
} else
Receiver = EmitScalarExpr(E->getInstanceReceiver());
break;
case ObjCMessageExpr::Class: {
ReceiverType = E->getClassReceiver();
const ObjCObjectType *ObjTy = ReceiverType->getAs<ObjCObjectType>();
assert(ObjTy && "Invalid Objective-C class message send");
OID = ObjTy->getInterface();
assert(OID && "Invalid Objective-C class message send");
Receiver = Runtime.GetClass(Builder, OID);
isClassMessage = true;
break;
}
case ObjCMessageExpr::SuperInstance:
ReceiverType = E->getSuperType();
Receiver = LoadObjCSelf();
isSuperMessage = true;
break;
case ObjCMessageExpr::SuperClass:
ReceiverType = E->getSuperType();
Receiver = LoadObjCSelf();
isSuperMessage = true;
isClassMessage = true;
break;
}
if (retainSelf)
Receiver = EmitARCRetainNonBlock(Receiver);
// In ARC, we sometimes want to "extend the lifetime"
// (i.e. retain+autorelease) of receivers of returns-inner-pointer
// messages.
if (getLangOptions().ObjCAutoRefCount && method &&
method->hasAttr<ObjCReturnsInnerPointerAttr>() &&
shouldExtendReceiverForInnerPointerMessage(E))
Receiver = EmitARCRetainAutorelease(ReceiverType, Receiver);
QualType ResultType =
method ? method->getResultType() : E->getType();
CallArgList Args;
EmitCallArgs(Args, method, E->arg_begin(), E->arg_end());
// For delegate init calls in ARC, do an unsafe store of null into
// self. This represents the call taking direct ownership of that
// value. We have to do this after emitting the other call
// arguments because they might also reference self, but we don't
// have to worry about any of them modifying self because that would
// be an undefined read and write of an object in unordered
// expressions.
if (isDelegateInit) {
assert(getLangOptions().ObjCAutoRefCount &&
"delegate init calls should only be marked in ARC");
// Do an unsafe store of null into self.
llvm::Value *selfAddr =
LocalDeclMap[cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl()];
assert(selfAddr && "no self entry for a delegate init call?");
Builder.CreateStore(getNullForVariable(selfAddr), selfAddr);
}
RValue result;
if (isSuperMessage) {
// super is only valid in an Objective-C method
const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
bool isCategoryImpl = isa<ObjCCategoryImplDecl>(OMD->getDeclContext());
result = Runtime.GenerateMessageSendSuper(*this, Return, ResultType,
E->getSelector(),
OMD->getClassInterface(),
isCategoryImpl,
Receiver,
isClassMessage,
Args,
method);
} else {
result = Runtime.GenerateMessageSend(*this, Return, ResultType,
E->getSelector(),
Receiver, Args, OID,
method);
}
// For delegate init calls in ARC, implicitly store the result of
// the call back into self. This takes ownership of the value.
if (isDelegateInit) {
llvm::Value *selfAddr =
LocalDeclMap[cast<ObjCMethodDecl>(CurCodeDecl)->getSelfDecl()];
llvm::Value *newSelf = result.getScalarVal();
// The delegate return type isn't necessarily a matching type; in
// fact, it's quite likely to be 'id'.
llvm::Type *selfTy =
cast<llvm::PointerType>(selfAddr->getType())->getElementType();
newSelf = Builder.CreateBitCast(newSelf, selfTy);
Builder.CreateStore(newSelf, selfAddr);
}
return AdjustRelatedResultType(*this, E, method, result);
}
namespace {
struct FinishARCDealloc : EHScopeStack::Cleanup {
void Emit(CodeGenFunction &CGF, Flags flags) {
const ObjCMethodDecl *method = cast<ObjCMethodDecl>(CGF.CurCodeDecl);
const ObjCImplDecl *impl = cast<ObjCImplDecl>(method->getDeclContext());
const ObjCInterfaceDecl *iface = impl->getClassInterface();
if (!iface->getSuperClass()) return;
bool isCategory = isa<ObjCCategoryImplDecl>(impl);
// Call [super dealloc] if we have a superclass.
llvm::Value *self = CGF.LoadObjCSelf();
CallArgList args;
CGF.CGM.getObjCRuntime().GenerateMessageSendSuper(CGF, ReturnValueSlot(),
CGF.getContext().VoidTy,
method->getSelector(),
iface,
isCategory,
self,
/*is class msg*/ false,
args,
method);
}
};
}
/// StartObjCMethod - Begin emission of an ObjCMethod. This generates
/// the LLVM function and sets the other context used by
/// CodeGenFunction.
void CodeGenFunction::StartObjCMethod(const ObjCMethodDecl *OMD,
const ObjCContainerDecl *CD,
SourceLocation StartLoc) {
FunctionArgList args;
// Check if we should generate debug info for this method.
if (CGM.getModuleDebugInfo() && !OMD->hasAttr<NoDebugAttr>())
DebugInfo = CGM.getModuleDebugInfo();
llvm::Function *Fn = CGM.getObjCRuntime().GenerateMethod(OMD, CD);
const CGFunctionInfo &FI = CGM.getTypes().getFunctionInfo(OMD);
CGM.SetInternalFunctionAttributes(OMD, Fn, FI);
args.push_back(OMD->getSelfDecl());
args.push_back(OMD->getCmdDecl());
for (ObjCMethodDecl::param_iterator PI = OMD->param_begin(),
E = OMD->param_end(); PI != E; ++PI)
args.push_back(*PI);
CurGD = OMD;
StartFunction(OMD, OMD->getResultType(), Fn, FI, args, StartLoc);
// In ARC, certain methods get an extra cleanup.
if (CGM.getLangOptions().ObjCAutoRefCount &&
OMD->isInstanceMethod() &&
OMD->getSelector().isUnarySelector()) {
const IdentifierInfo *ident =
OMD->getSelector().getIdentifierInfoForSlot(0);
if (ident->isStr("dealloc"))
EHStack.pushCleanup<FinishARCDealloc>(getARCCleanupKind());
}
}
static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF,
LValue lvalue, QualType type);
void CodeGenFunction::GenerateObjCGetterBody(ObjCIvarDecl *Ivar,
bool IsAtomic, bool IsStrong) {
LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(),
Ivar, 0);
llvm::Value *GetCopyStructFn =
CGM.getObjCRuntime().GetGetStructFunction();
CodeGenTypes &Types = CGM.getTypes();
// objc_copyStruct (ReturnValue, &structIvar,
// sizeof (Type of Ivar), isAtomic, false);
CallArgList Args;
RValue RV = RValue::get(Builder.CreateBitCast(ReturnValue, VoidPtrTy));
Args.add(RV, getContext().VoidPtrTy);
RV = RValue::get(Builder.CreateBitCast(LV.getAddress(), VoidPtrTy));
Args.add(RV, getContext().VoidPtrTy);
// sizeof (Type of Ivar)
CharUnits Size = getContext().getTypeSizeInChars(Ivar->getType());
llvm::Value *SizeVal =
llvm::ConstantInt::get(Types.ConvertType(getContext().LongTy),
Size.getQuantity());
Args.add(RValue::get(SizeVal), getContext().LongTy);
llvm::Value *isAtomic =
llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy),
IsAtomic ? 1 : 0);
Args.add(RValue::get(isAtomic), getContext().BoolTy);
llvm::Value *hasStrong =
llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy),
IsStrong ? 1 : 0);
Args.add(RValue::get(hasStrong), getContext().BoolTy);
EmitCall(Types.getFunctionInfo(getContext().VoidTy, Args,
FunctionType::ExtInfo()),
GetCopyStructFn, ReturnValueSlot(), Args);
}
/// Generate an Objective-C method. An Objective-C method is a C function with
/// its pointer, name, and types registered in the class struture.
void CodeGenFunction::GenerateObjCMethod(const ObjCMethodDecl *OMD) {
StartObjCMethod(OMD, OMD->getClassInterface(), OMD->getLocStart());
EmitStmt(OMD->getBody());
FinishFunction(OMD->getBodyRBrace());
}
// FIXME: I wasn't sure about the synthesis approach. If we end up generating an
// AST for the whole body we can just fall back to having a GenerateFunction
// which takes the body Stmt.
/// GenerateObjCGetter - Generate an Objective-C property getter
/// function. The given Decl must be an ObjCImplementationDecl. @synthesize
/// is illegal within a category.
void CodeGenFunction::GenerateObjCGetter(ObjCImplementationDecl *IMP,
const ObjCPropertyImplDecl *PID) {
ObjCIvarDecl *Ivar = PID->getPropertyIvarDecl();
const ObjCPropertyDecl *PD = PID->getPropertyDecl();
bool IsAtomic =
!(PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic);
ObjCMethodDecl *OMD = PD->getGetterMethodDecl();
assert(OMD && "Invalid call to generate getter (empty method)");
StartObjCMethod(OMD, IMP->getClassInterface(), PID->getLocStart());
// Determine if we should use an objc_getProperty call for
// this. Non-atomic properties are directly evaluated.
// atomic 'copy' and 'retain' properties are also directly
// evaluated in gc-only mode.
if (CGM.getLangOptions().getGCMode() != LangOptions::GCOnly &&
IsAtomic &&
(PD->getSetterKind() == ObjCPropertyDecl::Copy ||
PD->getSetterKind() == ObjCPropertyDecl::Retain)) {
llvm::Value *GetPropertyFn =
CGM.getObjCRuntime().GetPropertyGetFunction();
if (!GetPropertyFn) {
CGM.ErrorUnsupported(PID, "Obj-C getter requiring atomic copy");
FinishFunction();
return;
}
// Return (ivar-type) objc_getProperty((id) self, _cmd, offset, true).
// FIXME: Can't this be simpler? This might even be worse than the
// corresponding gcc code.
CodeGenTypes &Types = CGM.getTypes();
ValueDecl *Cmd = OMD->getCmdDecl();
llvm::Value *CmdVal = Builder.CreateLoad(LocalDeclMap[Cmd], "cmd");
QualType IdTy = getContext().getObjCIdType();
llvm::Value *SelfAsId =
Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy));
llvm::Value *Offset = EmitIvarOffset(IMP->getClassInterface(), Ivar);
llvm::Value *True =
llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 1);
CallArgList Args;
Args.add(RValue::get(SelfAsId), IdTy);
Args.add(RValue::get(CmdVal), Cmd->getType());
Args.add(RValue::get(Offset), getContext().getPointerDiffType());
Args.add(RValue::get(True), getContext().BoolTy);
// FIXME: We shouldn't need to get the function info here, the
// runtime already should have computed it to build the function.
RValue RV = EmitCall(Types.getFunctionInfo(PD->getType(), Args,
FunctionType::ExtInfo()),
GetPropertyFn, ReturnValueSlot(), Args);
// We need to fix the type here. Ivars with copy & retain are
// always objects so we don't need to worry about complex or
// aggregates.
RV = RValue::get(Builder.CreateBitCast(RV.getScalarVal(),
Types.ConvertType(PD->getType())));
EmitReturnOfRValue(RV, PD->getType());
// objc_getProperty does an autorelease, so we should suppress ours.
AutoreleaseResult = false;
} else {
const llvm::Triple &Triple = getContext().Target.getTriple();
QualType IVART = Ivar->getType();
if (IsAtomic &&
IVART->isScalarType() &&
(Triple.getArch() == llvm::Triple::arm ||
Triple.getArch() == llvm::Triple::thumb) &&
(getContext().getTypeSizeInChars(IVART)
> CharUnits::fromQuantity(4)) &&
CGM.getObjCRuntime().GetGetStructFunction()) {
GenerateObjCGetterBody(Ivar, true, false);
}
else if (IsAtomic &&
(IVART->isScalarType() && !IVART->isRealFloatingType()) &&
Triple.getArch() == llvm::Triple::x86 &&
(getContext().getTypeSizeInChars(IVART)
> CharUnits::fromQuantity(4)) &&
CGM.getObjCRuntime().GetGetStructFunction()) {
GenerateObjCGetterBody(Ivar, true, false);
}
else if (IsAtomic &&
(IVART->isScalarType() && !IVART->isRealFloatingType()) &&
Triple.getArch() == llvm::Triple::x86_64 &&
(getContext().getTypeSizeInChars(IVART)
> CharUnits::fromQuantity(8)) &&
CGM.getObjCRuntime().GetGetStructFunction()) {
GenerateObjCGetterBody(Ivar, true, false);
}
else if (IVART->isAnyComplexType()) {
LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(),
Ivar, 0);
ComplexPairTy Pair = LoadComplexFromAddr(LV.getAddress(),
LV.isVolatileQualified());
StoreComplexToAddr(Pair, ReturnValue, LV.isVolatileQualified());
}
else if (hasAggregateLLVMType(IVART)) {
bool IsStrong = false;
if ((IsStrong = IvarTypeWithAggrGCObjects(IVART))
&& CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::Indirect
&& CGM.getObjCRuntime().GetGetStructFunction()) {
GenerateObjCGetterBody(Ivar, IsAtomic, IsStrong);
}
else {
const CXXRecordDecl *classDecl = IVART->getAsCXXRecordDecl();
if (PID->getGetterCXXConstructor() &&
classDecl && !classDecl->hasTrivialDefaultConstructor()) {
ReturnStmt *Stmt =
new (getContext()) ReturnStmt(SourceLocation(),
PID->getGetterCXXConstructor(),
0);
EmitReturnStmt(*Stmt);
} else if (IsAtomic &&
!IVART->isAnyComplexType() &&
Triple.getArch() == llvm::Triple::x86 &&
(getContext().getTypeSizeInChars(IVART)
> CharUnits::fromQuantity(4)) &&
CGM.getObjCRuntime().GetGetStructFunction()) {
GenerateObjCGetterBody(Ivar, true, false);
}
else if (IsAtomic &&
!IVART->isAnyComplexType() &&
Triple.getArch() == llvm::Triple::x86_64 &&
(getContext().getTypeSizeInChars(IVART)
> CharUnits::fromQuantity(8)) &&
CGM.getObjCRuntime().GetGetStructFunction()) {
GenerateObjCGetterBody(Ivar, true, false);
}
else {
LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(),
Ivar, 0);
EmitAggregateCopy(ReturnValue, LV.getAddress(), IVART);
}
}
} else {
LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(),
Ivar, 0);
QualType propType = PD->getType();
llvm::Value *value;
if (propType->isReferenceType()) {
value = LV.getAddress();
} else {
// We want to load and autoreleaseReturnValue ARC __weak ivars.
if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
value = emitARCRetainLoadOfScalar(*this, LV, IVART);
// Otherwise we want to do a simple load, suppressing the
// final autorelease.
} else {
value = EmitLoadOfLValue(LV).getScalarVal();
AutoreleaseResult = false;
}
value = Builder.CreateBitCast(value, ConvertType(propType));
}
EmitReturnOfRValue(RValue::get(value), propType);
}
}
FinishFunction();
}
void CodeGenFunction::GenerateObjCAtomicSetterBody(ObjCMethodDecl *OMD,
ObjCIvarDecl *Ivar) {
// objc_copyStruct (&structIvar, &Arg,
// sizeof (struct something), true, false);
llvm::Value *GetCopyStructFn =
CGM.getObjCRuntime().GetSetStructFunction();
CodeGenTypes &Types = CGM.getTypes();
CallArgList Args;
LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), Ivar, 0);
RValue RV =
RValue::get(Builder.CreateBitCast(LV.getAddress(),
Types.ConvertType(getContext().VoidPtrTy)));
Args.add(RV, getContext().VoidPtrTy);
llvm::Value *Arg = LocalDeclMap[*OMD->param_begin()];
llvm::Value *ArgAsPtrTy =
Builder.CreateBitCast(Arg,
Types.ConvertType(getContext().VoidPtrTy));
RV = RValue::get(ArgAsPtrTy);
Args.add(RV, getContext().VoidPtrTy);
// sizeof (Type of Ivar)
CharUnits Size = getContext().getTypeSizeInChars(Ivar->getType());
llvm::Value *SizeVal =
llvm::ConstantInt::get(Types.ConvertType(getContext().LongTy),
Size.getQuantity());
Args.add(RValue::get(SizeVal), getContext().LongTy);
llvm::Value *True =
llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 1);
Args.add(RValue::get(True), getContext().BoolTy);
llvm::Value *False =
llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 0);
Args.add(RValue::get(False), getContext().BoolTy);
EmitCall(Types.getFunctionInfo(getContext().VoidTy, Args,
FunctionType::ExtInfo()),
GetCopyStructFn, ReturnValueSlot(), Args);
}
static bool
IvarAssignHasTrvialAssignment(const ObjCPropertyImplDecl *PID,
QualType IvarT) {
bool HasTrvialAssignment = true;
if (PID->getSetterCXXAssignment()) {
const CXXRecordDecl *classDecl = IvarT->getAsCXXRecordDecl();
HasTrvialAssignment =
(!classDecl || classDecl->hasTrivialCopyAssignment());
}
return HasTrvialAssignment;
}
/// GenerateObjCSetter - Generate an Objective-C property setter
/// function. The given Decl must be an ObjCImplementationDecl. @synthesize
/// is illegal within a category.
void CodeGenFunction::GenerateObjCSetter(ObjCImplementationDecl *IMP,
const ObjCPropertyImplDecl *PID) {
ObjCIvarDecl *Ivar = PID->getPropertyIvarDecl();
const ObjCPropertyDecl *PD = PID->getPropertyDecl();
ObjCMethodDecl *OMD = PD->getSetterMethodDecl();
assert(OMD && "Invalid call to generate setter (empty method)");
StartObjCMethod(OMD, IMP->getClassInterface(), PID->getLocStart());
const llvm::Triple &Triple = getContext().Target.getTriple();
QualType IVART = Ivar->getType();
bool IsCopy = PD->getSetterKind() == ObjCPropertyDecl::Copy;
bool IsAtomic =
!(PD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_nonatomic);
// Determine if we should use an objc_setProperty call for
// this. Properties with 'copy' semantics always use it, as do
// non-atomic properties with 'release' semantics as long as we are
// not in gc-only mode.
if (IsCopy ||
(CGM.getLangOptions().getGCMode() != LangOptions::GCOnly &&
PD->getSetterKind() == ObjCPropertyDecl::Retain)) {
llvm::Value *SetPropertyFn =
CGM.getObjCRuntime().GetPropertySetFunction();
if (!SetPropertyFn) {
CGM.ErrorUnsupported(PID, "Obj-C getter requiring atomic copy");
FinishFunction();
return;
}
// Emit objc_setProperty((id) self, _cmd, offset, arg,
// <is-atomic>, <is-copy>).
// FIXME: Can't this be simpler? This might even be worse than the
// corresponding gcc code.
CodeGenTypes &Types = CGM.getTypes();
ValueDecl *Cmd = OMD->getCmdDecl();
llvm::Value *CmdVal = Builder.CreateLoad(LocalDeclMap[Cmd], "cmd");
QualType IdTy = getContext().getObjCIdType();
llvm::Value *SelfAsId =
Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy));
llvm::Value *Offset = EmitIvarOffset(IMP->getClassInterface(), Ivar);
llvm::Value *Arg = LocalDeclMap[*OMD->param_begin()];
llvm::Value *ArgAsId =
Builder.CreateBitCast(Builder.CreateLoad(Arg, "arg"),
Types.ConvertType(IdTy));
llvm::Value *True =
llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 1);
llvm::Value *False =
llvm::ConstantInt::get(Types.ConvertType(getContext().BoolTy), 0);
CallArgList Args;
Args.add(RValue::get(SelfAsId), IdTy);
Args.add(RValue::get(CmdVal), Cmd->getType());
Args.add(RValue::get(Offset), getContext().getPointerDiffType());
Args.add(RValue::get(ArgAsId), IdTy);
Args.add(RValue::get(IsAtomic ? True : False), getContext().BoolTy);
Args.add(RValue::get(IsCopy ? True : False), getContext().BoolTy);
// FIXME: We shouldn't need to get the function info here, the runtime
// already should have computed it to build the function.
EmitCall(Types.getFunctionInfo(getContext().VoidTy, Args,
FunctionType::ExtInfo()),
SetPropertyFn,
ReturnValueSlot(), Args);
} else if (IsAtomic && hasAggregateLLVMType(IVART) &&
!IVART->isAnyComplexType() &&
IvarAssignHasTrvialAssignment(PID, IVART) &&
((Triple.getArch() == llvm::Triple::x86 &&
(getContext().getTypeSizeInChars(IVART)
> CharUnits::fromQuantity(4))) ||
(Triple.getArch() == llvm::Triple::x86_64 &&
(getContext().getTypeSizeInChars(IVART)
> CharUnits::fromQuantity(8))))
&& CGM.getObjCRuntime().GetSetStructFunction()) {
// objc_copyStruct (&structIvar, &Arg,
// sizeof (struct something), true, false);
GenerateObjCAtomicSetterBody(OMD, Ivar);
} else if (PID->getSetterCXXAssignment()) {
EmitIgnoredExpr(PID->getSetterCXXAssignment());
} else {
if (IsAtomic &&
IVART->isScalarType() &&
(Triple.getArch() == llvm::Triple::arm ||
Triple.getArch() == llvm::Triple::thumb) &&
(getContext().getTypeSizeInChars(IVART)
> CharUnits::fromQuantity(4)) &&
CGM.getObjCRuntime().GetGetStructFunction()) {
GenerateObjCAtomicSetterBody(OMD, Ivar);
}
else if (IsAtomic &&
(IVART->isScalarType() && !IVART->isRealFloatingType()) &&
Triple.getArch() == llvm::Triple::x86 &&
(getContext().getTypeSizeInChars(IVART)
> CharUnits::fromQuantity(4)) &&
CGM.getObjCRuntime().GetGetStructFunction()) {
GenerateObjCAtomicSetterBody(OMD, Ivar);
}
else if (IsAtomic &&
(IVART->isScalarType() && !IVART->isRealFloatingType()) &&
Triple.getArch() == llvm::Triple::x86_64 &&
(getContext().getTypeSizeInChars(IVART)
> CharUnits::fromQuantity(8)) &&
CGM.getObjCRuntime().GetGetStructFunction()) {
GenerateObjCAtomicSetterBody(OMD, Ivar);
}
else {
// FIXME: Find a clean way to avoid AST node creation.
SourceLocation Loc = PID->getLocStart();
ValueDecl *Self = OMD->getSelfDecl();
ObjCIvarDecl *Ivar = PID->getPropertyIvarDecl();
DeclRefExpr Base(Self, Self->getType(), VK_RValue, Loc);
ParmVarDecl *ArgDecl = *OMD->param_begin();
QualType T = ArgDecl->getType();
if (T->isReferenceType())
T = cast<ReferenceType>(T)->getPointeeType();
DeclRefExpr Arg(ArgDecl, T, VK_LValue, Loc);
ObjCIvarRefExpr IvarRef(Ivar, Ivar->getType(), Loc, &Base, true, true);
// The property type can differ from the ivar type in some situations with
// Objective-C pointer types, we can always bit cast the RHS in these cases.
if (getContext().getCanonicalType(Ivar->getType()) !=
getContext().getCanonicalType(ArgDecl->getType())) {
ImplicitCastExpr ArgCasted(ImplicitCastExpr::OnStack,
Ivar->getType(), CK_BitCast, &Arg,
VK_RValue);
BinaryOperator Assign(&IvarRef, &ArgCasted, BO_Assign,
Ivar->getType(), VK_RValue, OK_Ordinary, Loc);
EmitStmt(&Assign);
} else {
BinaryOperator Assign(&IvarRef, &Arg, BO_Assign,
Ivar->getType(), VK_RValue, OK_Ordinary, Loc);
EmitStmt(&Assign);
}
}
}
FinishFunction();
}
namespace {
struct DestroyIvar : EHScopeStack::Cleanup {
private:
llvm::Value *addr;
const ObjCIvarDecl *ivar;
CodeGenFunction::Destroyer &destroyer;
bool useEHCleanupForArray;
public:
DestroyIvar(llvm::Value *addr, const ObjCIvarDecl *ivar,
CodeGenFunction::Destroyer *destroyer,
bool useEHCleanupForArray)
: addr(addr), ivar(ivar), destroyer(*destroyer),
useEHCleanupForArray(useEHCleanupForArray) {}
void Emit(CodeGenFunction &CGF, Flags flags) {
LValue lvalue
= CGF.EmitLValueForIvar(CGF.TypeOfSelfObject(), addr, ivar, /*CVR*/ 0);
CGF.emitDestroy(lvalue.getAddress(), ivar->getType(), destroyer,
flags.isForNormalCleanup() && useEHCleanupForArray);
}
};
}
/// Like CodeGenFunction::destroyARCStrong, but do it with a call.
static void destroyARCStrongWithStore(CodeGenFunction &CGF,
llvm::Value *addr,
QualType type) {
llvm::Value *null = getNullForVariable(addr);
CGF.EmitARCStoreStrongCall(addr, null, /*ignored*/ true);
}
static void emitCXXDestructMethod(CodeGenFunction &CGF,
ObjCImplementationDecl *impl) {
CodeGenFunction::RunCleanupsScope scope(CGF);
llvm::Value *self = CGF.LoadObjCSelf();
const ObjCInterfaceDecl *iface = impl->getClassInterface();
for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
ivar; ivar = ivar->getNextIvar()) {
QualType type = ivar->getType();
// Check whether the ivar is a destructible type.
QualType::DestructionKind dtorKind = type.isDestructedType();
if (!dtorKind) continue;
CodeGenFunction::Destroyer *destroyer = 0;
// Use a call to objc_storeStrong to destroy strong ivars, for the
// general benefit of the tools.
if (dtorKind == QualType::DK_objc_strong_lifetime) {
destroyer = &destroyARCStrongWithStore;
// Otherwise use the default for the destruction kind.
} else {
destroyer = &CGF.getDestroyer(dtorKind);
}
CleanupKind cleanupKind = CGF.getCleanupKind(dtorKind);
CGF.EHStack.pushCleanup<DestroyIvar>(cleanupKind, self, ivar, destroyer,
cleanupKind & EHCleanup);
}
assert(scope.requiresCleanups() && "nothing to do in .cxx_destruct?");
}
void CodeGenFunction::GenerateObjCCtorDtorMethod(ObjCImplementationDecl *IMP,
ObjCMethodDecl *MD,
bool ctor) {
MD->createImplicitParams(CGM.getContext(), IMP->getClassInterface());
StartObjCMethod(MD, IMP->getClassInterface(), MD->getLocStart());
// Emit .cxx_construct.
if (ctor) {
// Suppress the final autorelease in ARC.
AutoreleaseResult = false;
SmallVector<CXXCtorInitializer *, 8> IvarInitializers;
for (ObjCImplementationDecl::init_const_iterator B = IMP->init_begin(),
E = IMP->init_end(); B != E; ++B) {
CXXCtorInitializer *IvarInit = (*B);
FieldDecl *Field = IvarInit->getAnyMember();
ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(Field);
LValue LV = EmitLValueForIvar(TypeOfSelfObject(),
LoadObjCSelf(), Ivar, 0);
EmitAggExpr(IvarInit->getInit(),
AggValueSlot::forLValue(LV, AggValueSlot::IsDestructed,
AggValueSlot::DoesNotNeedGCBarriers,
AggValueSlot::IsNotAliased));
}
// constructor returns 'self'.
CodeGenTypes &Types = CGM.getTypes();
QualType IdTy(CGM.getContext().getObjCIdType());
llvm::Value *SelfAsId =
Builder.CreateBitCast(LoadObjCSelf(), Types.ConvertType(IdTy));
EmitReturnOfRValue(RValue::get(SelfAsId), IdTy);
// Emit .cxx_destruct.
} else {
emitCXXDestructMethod(*this, IMP);
}
FinishFunction();
}
bool CodeGenFunction::IndirectObjCSetterArg(const CGFunctionInfo &FI) {
CGFunctionInfo::const_arg_iterator it = FI.arg_begin();
it++; it++;
const ABIArgInfo &AI = it->info;
// FIXME. Is this sufficient check?
return (AI.getKind() == ABIArgInfo::Indirect);
}
bool CodeGenFunction::IvarTypeWithAggrGCObjects(QualType Ty) {
if (CGM.getLangOptions().getGCMode() == LangOptions::NonGC)
return false;
if (const RecordType *FDTTy = Ty.getTypePtr()->getAs<RecordType>())
return FDTTy->getDecl()->hasObjectMember();
return false;
}
llvm::Value *CodeGenFunction::LoadObjCSelf() {
const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
return Builder.CreateLoad(LocalDeclMap[OMD->getSelfDecl()], "self");
}
QualType CodeGenFunction::TypeOfSelfObject() {
const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CurFuncDecl);
ImplicitParamDecl *selfDecl = OMD->getSelfDecl();
const ObjCObjectPointerType *PTy = cast<ObjCObjectPointerType>(
getContext().getCanonicalType(selfDecl->getType()));
return PTy->getPointeeType();
}
LValue
CodeGenFunction::EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E) {
// This is a special l-value that just issues sends when we load or
// store through it.
// For certain base kinds, we need to emit the base immediately.
llvm::Value *Base;
if (E->isSuperReceiver())
Base = LoadObjCSelf();
else if (E->isClassReceiver())
Base = CGM.getObjCRuntime().GetClass(Builder, E->getClassReceiver());
else
Base = EmitScalarExpr(E->getBase());
return LValue::MakePropertyRef(E, Base);
}
static RValue GenerateMessageSendSuper(CodeGenFunction &CGF,
ReturnValueSlot Return,
QualType ResultType,
Selector S,
llvm::Value *Receiver,
const CallArgList &CallArgs) {
const ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(CGF.CurFuncDecl);
bool isClassMessage = OMD->isClassMethod();
bool isCategoryImpl = isa<ObjCCategoryImplDecl>(OMD->getDeclContext());
return CGF.CGM.getObjCRuntime()
.GenerateMessageSendSuper(CGF, Return, ResultType,
S, OMD->getClassInterface(),
isCategoryImpl, Receiver,
isClassMessage, CallArgs);
}
RValue CodeGenFunction::EmitLoadOfPropertyRefLValue(LValue LV,
ReturnValueSlot Return) {
const ObjCPropertyRefExpr *E = LV.getPropertyRefExpr();
QualType ResultType = E->getGetterResultType();
Selector S;
const ObjCMethodDecl *method;
if (E->isExplicitProperty()) {
const ObjCPropertyDecl *Property = E->getExplicitProperty();
S = Property->getGetterName();
method = Property->getGetterMethodDecl();
} else {
method = E->getImplicitPropertyGetter();
S = method->getSelector();
}
llvm::Value *Receiver = LV.getPropertyRefBaseAddr();
if (CGM.getLangOptions().ObjCAutoRefCount) {
QualType receiverType;
if (E->isSuperReceiver())
receiverType = E->getSuperReceiverType();
else if (E->isClassReceiver())
receiverType = getContext().getObjCClassType();
else
receiverType = E->getBase()->getType();
}
// Accesses to 'super' follow a different code path.
if (E->isSuperReceiver())
return AdjustRelatedResultType(*this, E, method,
GenerateMessageSendSuper(*this, Return,
ResultType,
S, Receiver,
CallArgList()));
const ObjCInterfaceDecl *ReceiverClass
= (E->isClassReceiver() ? E->getClassReceiver() : 0);
return AdjustRelatedResultType(*this, E, method,
CGM.getObjCRuntime().
GenerateMessageSend(*this, Return, ResultType, S,
Receiver, CallArgList(), ReceiverClass));
}
void CodeGenFunction::EmitStoreThroughPropertyRefLValue(RValue Src,
LValue Dst) {
const ObjCPropertyRefExpr *E = Dst.getPropertyRefExpr();
Selector S = E->getSetterSelector();
QualType ArgType = E->getSetterArgType();
// FIXME. Other than scalars, AST is not adequate for setter and
// getter type mismatches which require conversion.
if (Src.isScalar()) {
llvm::Value *SrcVal = Src.getScalarVal();
QualType DstType = getContext().getCanonicalType(ArgType);
llvm::Type *DstTy = ConvertType(DstType);
if (SrcVal->getType() != DstTy)
Src =
RValue::get(EmitScalarConversion(SrcVal, E->getType(), DstType));
}
CallArgList Args;
Args.add(Src, ArgType);
llvm::Value *Receiver = Dst.getPropertyRefBaseAddr();
QualType ResultType = getContext().VoidTy;
if (E->isSuperReceiver()) {
GenerateMessageSendSuper(*this, ReturnValueSlot(),
ResultType, S, Receiver, Args);
return;
}
const ObjCInterfaceDecl *ReceiverClass
= (E->isClassReceiver() ? E->getClassReceiver() : 0);
CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
ResultType, S, Receiver, Args,
ReceiverClass);
}
void CodeGenFunction::EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S){
llvm::Constant *EnumerationMutationFn =
CGM.getObjCRuntime().EnumerationMutationFunction();
if (!EnumerationMutationFn) {
CGM.ErrorUnsupported(&S, "Obj-C fast enumeration for this runtime");
return;
}
CGDebugInfo *DI = getDebugInfo();
if (DI) {
DI->setLocation(S.getSourceRange().getBegin());
DI->EmitRegionStart(Builder);
}
// The local variable comes into scope immediately.
AutoVarEmission variable = AutoVarEmission::invalid();
if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement()))
variable = EmitAutoVarAlloca(*cast<VarDecl>(SD->getSingleDecl()));
JumpDest LoopEnd = getJumpDestInCurrentScope("forcoll.end");
// Fast enumeration state.
QualType StateTy = CGM.getObjCFastEnumerationStateType();
llvm::Value *StatePtr = CreateMemTemp(StateTy, "state.ptr");
EmitNullInitialization(StatePtr, StateTy);
// Number of elements in the items array.
static const unsigned NumItems = 16;
// Fetch the countByEnumeratingWithState:objects:count: selector.
IdentifierInfo *II[] = {
&CGM.getContext().Idents.get("countByEnumeratingWithState"),
&CGM.getContext().Idents.get("objects"),
&CGM.getContext().Idents.get("count")
};
Selector FastEnumSel =
CGM.getContext().Selectors.getSelector(llvm::array_lengthof(II), &II[0]);
QualType ItemsTy =
getContext().getConstantArrayType(getContext().getObjCIdType(),
llvm::APInt(32, NumItems),
ArrayType::Normal, 0);
llvm::Value *ItemsPtr = CreateMemTemp(ItemsTy, "items.ptr");
// Emit the collection pointer. In ARC, we do a retain.
llvm::Value *Collection;
if (getLangOptions().ObjCAutoRefCount) {
Collection = EmitARCRetainScalarExpr(S.getCollection());
// Enter a cleanup to do the release.
EmitObjCConsumeObject(S.getCollection()->getType(), Collection);
} else {
Collection = EmitScalarExpr(S.getCollection());
}
// The 'continue' label needs to appear within the cleanup for the
// collection object.
JumpDest AfterBody = getJumpDestInCurrentScope("forcoll.next");
// Send it our message:
CallArgList Args;
// The first argument is a temporary of the enumeration-state type.
Args.add(RValue::get(StatePtr), getContext().getPointerType(StateTy));
// The second argument is a temporary array with space for NumItems
// pointers. We'll actually be loading elements from the array
// pointer written into the control state; this buffer is so that
// collections that *aren't* backed by arrays can still queue up
// batches of elements.
Args.add(RValue::get(ItemsPtr), getContext().getPointerType(ItemsTy));
// The third argument is the capacity of that temporary array.
llvm::Type *UnsignedLongLTy = ConvertType(getContext().UnsignedLongTy);
llvm::Constant *Count = llvm::ConstantInt::get(UnsignedLongLTy, NumItems);
Args.add(RValue::get(Count), getContext().UnsignedLongTy);
// Start the enumeration.
RValue CountRV =
CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
getContext().UnsignedLongTy,
FastEnumSel,
Collection, Args);
// The initial number of objects that were returned in the buffer.
llvm::Value *initialBufferLimit = CountRV.getScalarVal();
llvm::BasicBlock *EmptyBB = createBasicBlock("forcoll.empty");
llvm::BasicBlock *LoopInitBB = createBasicBlock("forcoll.loopinit");
llvm::Value *zero = llvm::Constant::getNullValue(UnsignedLongLTy);
// If the limit pointer was zero to begin with, the collection is
// empty; skip all this.
Builder.CreateCondBr(Builder.CreateICmpEQ(initialBufferLimit, zero, "iszero"),
EmptyBB, LoopInitBB);
// Otherwise, initialize the loop.
EmitBlock(LoopInitBB);
// Save the initial mutations value. This is the value at an
// address that was written into the state object by
// countByEnumeratingWithState:objects:count:.
llvm::Value *StateMutationsPtrPtr =
Builder.CreateStructGEP(StatePtr, 2, "mutationsptr.ptr");
llvm::Value *StateMutationsPtr = Builder.CreateLoad(StateMutationsPtrPtr,
"mutationsptr");
llvm::Value *initialMutations =
Builder.CreateLoad(StateMutationsPtr, "forcoll.initial-mutations");
// Start looping. This is the point we return to whenever we have a
// fresh, non-empty batch of objects.
llvm::BasicBlock *LoopBodyBB = createBasicBlock("forcoll.loopbody");
EmitBlock(LoopBodyBB);
// The current index into the buffer.
llvm::PHINode *index = Builder.CreatePHI(UnsignedLongLTy, 3, "forcoll.index");
index->addIncoming(zero, LoopInitBB);
// The current buffer size.
llvm::PHINode *count = Builder.CreatePHI(UnsignedLongLTy, 3, "forcoll.count");
count->addIncoming(initialBufferLimit, LoopInitBB);
// Check whether the mutations value has changed from where it was
// at start. StateMutationsPtr should actually be invariant between
// refreshes.
StateMutationsPtr = Builder.CreateLoad(StateMutationsPtrPtr, "mutationsptr");
llvm::Value *currentMutations
= Builder.CreateLoad(StateMutationsPtr, "statemutations");
llvm::BasicBlock *WasMutatedBB = createBasicBlock("forcoll.mutated");
llvm::BasicBlock *WasNotMutatedBB = createBasicBlock("forcoll.notmutated");
Builder.CreateCondBr(Builder.CreateICmpEQ(currentMutations, initialMutations),
WasNotMutatedBB, WasMutatedBB);
// If so, call the enumeration-mutation function.
EmitBlock(WasMutatedBB);
llvm::Value *V =
Builder.CreateBitCast(Collection,
ConvertType(getContext().getObjCIdType()),
"tmp");
CallArgList Args2;
Args2.add(RValue::get(V), getContext().getObjCIdType());
// FIXME: We shouldn't need to get the function info here, the runtime already
// should have computed it to build the function.
EmitCall(CGM.getTypes().getFunctionInfo(getContext().VoidTy, Args2,
FunctionType::ExtInfo()),
EnumerationMutationFn, ReturnValueSlot(), Args2);
// Otherwise, or if the mutation function returns, just continue.
EmitBlock(WasNotMutatedBB);
// Initialize the element variable.
RunCleanupsScope elementVariableScope(*this);
bool elementIsVariable;
LValue elementLValue;
QualType elementType;
if (const DeclStmt *SD = dyn_cast<DeclStmt>(S.getElement())) {
// Initialize the variable, in case it's a __block variable or something.
EmitAutoVarInit(variable);
const VarDecl* D = cast<VarDecl>(SD->getSingleDecl());
DeclRefExpr tempDRE(const_cast<VarDecl*>(D), D->getType(),
VK_LValue, SourceLocation());
elementLValue = EmitLValue(&tempDRE);
elementType = D->getType();
elementIsVariable = true;
if (D->isARCPseudoStrong())
elementLValue.getQuals().setObjCLifetime(Qualifiers::OCL_ExplicitNone);
} else {
elementLValue = LValue(); // suppress warning
elementType = cast<Expr>(S.getElement())->getType();
elementIsVariable = false;
}
llvm::Type *convertedElementType = ConvertType(elementType);
// Fetch the buffer out of the enumeration state.
// TODO: this pointer should actually be invariant between
// refreshes, which would help us do certain loop optimizations.
llvm::Value *StateItemsPtr =
Builder.CreateStructGEP(StatePtr, 1, "stateitems.ptr");
llvm::Value *EnumStateItems =
Builder.CreateLoad(StateItemsPtr, "stateitems");
// Fetch the value at the current index from the buffer.
llvm::Value *CurrentItemPtr =
Builder.CreateGEP(EnumStateItems, index, "currentitem.ptr");
llvm::Value *CurrentItem = Builder.CreateLoad(CurrentItemPtr);
// Cast that value to the right type.
CurrentItem = Builder.CreateBitCast(CurrentItem, convertedElementType,
"currentitem");
// Make sure we have an l-value. Yes, this gets evaluated every
// time through the loop.
if (!elementIsVariable) {
elementLValue = EmitLValue(cast<Expr>(S.getElement()));
EmitStoreThroughLValue(RValue::get(CurrentItem), elementLValue);
} else {
EmitScalarInit(CurrentItem, elementLValue);
}
// If we do have an element variable, this assignment is the end of
// its initialization.
if (elementIsVariable)
EmitAutoVarCleanups(variable);
// Perform the loop body, setting up break and continue labels.
BreakContinueStack.push_back(BreakContinue(LoopEnd, AfterBody));
{
RunCleanupsScope Scope(*this);
EmitStmt(S.getBody());
}
BreakContinueStack.pop_back();
// Destroy the element variable now.
elementVariableScope.ForceCleanup();
// Check whether there are more elements.
EmitBlock(AfterBody.getBlock());
llvm::BasicBlock *FetchMoreBB = createBasicBlock("forcoll.refetch");
// First we check in the local buffer.
llvm::Value *indexPlusOne
= Builder.CreateAdd(index, llvm::ConstantInt::get(UnsignedLongLTy, 1));
// If we haven't overrun the buffer yet, we can continue.
Builder.CreateCondBr(Builder.CreateICmpULT(indexPlusOne, count),
LoopBodyBB, FetchMoreBB);
index->addIncoming(indexPlusOne, AfterBody.getBlock());
count->addIncoming(count, AfterBody.getBlock());
// Otherwise, we have to fetch more elements.
EmitBlock(FetchMoreBB);
CountRV =
CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
getContext().UnsignedLongTy,
FastEnumSel,
Collection, Args);
// If we got a zero count, we're done.
llvm::Value *refetchCount = CountRV.getScalarVal();
// (note that the message send might split FetchMoreBB)
index->addIncoming(zero, Builder.GetInsertBlock());
count->addIncoming(refetchCount, Builder.GetInsertBlock());
Builder.CreateCondBr(Builder.CreateICmpEQ(refetchCount, zero),
EmptyBB, LoopBodyBB);
// No more elements.
EmitBlock(EmptyBB);
if (!elementIsVariable) {
// If the element was not a declaration, set it to be null.
llvm::Value *null = llvm::Constant::getNullValue(convertedElementType);
elementLValue = EmitLValue(cast<Expr>(S.getElement()));
EmitStoreThroughLValue(RValue::get(null), elementLValue);
}
if (DI) {
DI->setLocation(S.getSourceRange().getEnd());
DI->EmitRegionEnd(Builder);
}
// Leave the cleanup we entered in ARC.
if (getLangOptions().ObjCAutoRefCount)
PopCleanupBlock();
EmitBlock(LoopEnd.getBlock());
}
void CodeGenFunction::EmitObjCAtTryStmt(const ObjCAtTryStmt &S) {
CGM.getObjCRuntime().EmitTryStmt(*this, S);
}
void CodeGenFunction::EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S) {
CGM.getObjCRuntime().EmitThrowStmt(*this, S);
}
void CodeGenFunction::EmitObjCAtSynchronizedStmt(
const ObjCAtSynchronizedStmt &S) {
CGM.getObjCRuntime().EmitSynchronizedStmt(*this, S);
}
/// Produce the code for a CK_ObjCProduceObject. Just does a
/// primitive retain.
llvm::Value *CodeGenFunction::EmitObjCProduceObject(QualType type,
llvm::Value *value) {
return EmitARCRetain(type, value);
}
namespace {
struct CallObjCRelease : EHScopeStack::Cleanup {
CallObjCRelease(llvm::Value *object) : object(object) {}
llvm::Value *object;
void Emit(CodeGenFunction &CGF, Flags flags) {
CGF.EmitARCRelease(object, /*precise*/ true);
}
};
}
/// Produce the code for a CK_ObjCConsumeObject. Does a primitive
/// release at the end of the full-expression.
llvm::Value *CodeGenFunction::EmitObjCConsumeObject(QualType type,
llvm::Value *object) {
// If we're in a conditional branch, we need to make the cleanup
// conditional.
pushFullExprCleanup<CallObjCRelease>(getARCCleanupKind(), object);
return object;
}
llvm::Value *CodeGenFunction::EmitObjCExtendObjectLifetime(QualType type,
llvm::Value *value) {
return EmitARCRetainAutorelease(type, value);
}
static llvm::Constant *createARCRuntimeFunction(CodeGenModule &CGM,
llvm::FunctionType *type,
StringRef fnName) {
llvm::Constant *fn = CGM.CreateRuntimeFunction(type, fnName);
// In -fobjc-no-arc-runtime, emit weak references to the runtime
// support library.
if (!CGM.getCodeGenOpts().ObjCRuntimeHasARC)
if (llvm::Function *f = dyn_cast<llvm::Function>(fn))
f->setLinkage(llvm::Function::ExternalWeakLinkage);
return fn;
}
/// Perform an operation having the signature
/// i8* (i8*)
/// where a null input causes a no-op and returns null.
static llvm::Value *emitARCValueOperation(CodeGenFunction &CGF,
llvm::Value *value,
llvm::Constant *&fn,
StringRef fnName) {
if (isa<llvm::ConstantPointerNull>(value)) return value;
if (!fn) {
std::vector<llvm::Type*> args(1, CGF.Int8PtrTy);
llvm::FunctionType *fnType =
llvm::FunctionType::get(CGF.Int8PtrTy, args, false);
fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName);
}
// Cast the argument to 'id'.
llvm::Type *origType = value->getType();
value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy);
// Call the function.
llvm::CallInst *call = CGF.Builder.CreateCall(fn, value);
call->setDoesNotThrow();
// Cast the result back to the original type.
return CGF.Builder.CreateBitCast(call, origType);
}
/// Perform an operation having the following signature:
/// i8* (i8**)
static llvm::Value *emitARCLoadOperation(CodeGenFunction &CGF,
llvm::Value *addr,
llvm::Constant *&fn,
StringRef fnName) {
if (!fn) {
std::vector<llvm::Type*> args(1, CGF.Int8PtrPtrTy);
llvm::FunctionType *fnType =
llvm::FunctionType::get(CGF.Int8PtrTy, args, false);
fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName);
}
// Cast the argument to 'id*'.
llvm::Type *origType = addr->getType();
addr = CGF.Builder.CreateBitCast(addr, CGF.Int8PtrPtrTy);
// Call the function.
llvm::CallInst *call = CGF.Builder.CreateCall(fn, addr);
call->setDoesNotThrow();
// Cast the result back to a dereference of the original type.
llvm::Value *result = call;
if (origType != CGF.Int8PtrPtrTy)
result = CGF.Builder.CreateBitCast(result,
cast<llvm::PointerType>(origType)->getElementType());
return result;
}
/// Perform an operation having the following signature:
/// i8* (i8**, i8*)
static llvm::Value *emitARCStoreOperation(CodeGenFunction &CGF,
llvm::Value *addr,
llvm::Value *value,
llvm::Constant *&fn,
StringRef fnName,
bool ignored) {
assert(cast<llvm::PointerType>(addr->getType())->getElementType()
== value->getType());
if (!fn) {
std::vector<llvm::Type*> argTypes(2);
argTypes[0] = CGF.Int8PtrPtrTy;
argTypes[1] = CGF.Int8PtrTy;
llvm::FunctionType *fnType
= llvm::FunctionType::get(CGF.Int8PtrTy, argTypes, false);
fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName);
}
llvm::Type *origType = value->getType();
addr = CGF.Builder.CreateBitCast(addr, CGF.Int8PtrPtrTy);
value = CGF.Builder.CreateBitCast(value, CGF.Int8PtrTy);
llvm::CallInst *result = CGF.Builder.CreateCall2(fn, addr, value);
result->setDoesNotThrow();
if (ignored) return 0;
return CGF.Builder.CreateBitCast(result, origType);
}
/// Perform an operation having the following signature:
/// void (i8**, i8**)
static void emitARCCopyOperation(CodeGenFunction &CGF,
llvm::Value *dst,
llvm::Value *src,
llvm::Constant *&fn,
StringRef fnName) {
assert(dst->getType() == src->getType());
if (!fn) {
std::vector<llvm::Type*> argTypes(2, CGF.Int8PtrPtrTy);
llvm::FunctionType *fnType
= llvm::FunctionType::get(CGF.Builder.getVoidTy(), argTypes, false);
fn = createARCRuntimeFunction(CGF.CGM, fnType, fnName);
}
dst = CGF.Builder.CreateBitCast(dst, CGF.Int8PtrPtrTy);
src = CGF.Builder.CreateBitCast(src, CGF.Int8PtrPtrTy);
llvm::CallInst *result = CGF.Builder.CreateCall2(fn, dst, src);
result->setDoesNotThrow();
}
/// Produce the code to do a retain. Based on the type, calls one of:
/// call i8* @objc_retain(i8* %value)
/// call i8* @objc_retainBlock(i8* %value)
llvm::Value *CodeGenFunction::EmitARCRetain(QualType type, llvm::Value *value) {
if (type->isBlockPointerType())
return EmitARCRetainBlock(value);
else
return EmitARCRetainNonBlock(value);
}
/// Retain the given object, with normal retain semantics.
/// call i8* @objc_retain(i8* %value)
llvm::Value *CodeGenFunction::EmitARCRetainNonBlock(llvm::Value *value) {
return emitARCValueOperation(*this, value,
CGM.getARCEntrypoints().objc_retain,
"objc_retain");
}
/// Retain the given block, with _Block_copy semantics.
/// call i8* @objc_retainBlock(i8* %value)
llvm::Value *CodeGenFunction::EmitARCRetainBlock(llvm::Value *value) {
return emitARCValueOperation(*this, value,
CGM.getARCEntrypoints().objc_retainBlock,
"objc_retainBlock");
}
/// Retain the given object which is the result of a function call.
/// call i8* @objc_retainAutoreleasedReturnValue(i8* %value)
///
/// Yes, this function name is one character away from a different
/// call with completely different semantics.
llvm::Value *
CodeGenFunction::EmitARCRetainAutoreleasedReturnValue(llvm::Value *value) {
// Fetch the void(void) inline asm which marks that we're going to
// retain the autoreleased return value.
llvm::InlineAsm *&marker
= CGM.getARCEntrypoints().retainAutoreleasedReturnValueMarker;
if (!marker) {
StringRef assembly
= CGM.getTargetCodeGenInfo()
.getARCRetainAutoreleasedReturnValueMarker();
// If we have an empty assembly string, there's nothing to do.
if (assembly.empty()) {
// Otherwise, at -O0, build an inline asm that we're going to call
// in a moment.
} else if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
llvm::FunctionType *type =
llvm::FunctionType::get(llvm::Type::getVoidTy(getLLVMContext()),
/*variadic*/ false);
marker = llvm::InlineAsm::get(type, assembly, "", /*sideeffects*/ true);
// If we're at -O1 and above, we don't want to litter the code
// with this marker yet, so leave a breadcrumb for the ARC
// optimizer to pick up.
} else {
llvm::NamedMDNode *metadata =
CGM.getModule().getOrInsertNamedMetadata(
"clang.arc.retainAutoreleasedReturnValueMarker");
assert(metadata->getNumOperands() <= 1);
if (metadata->getNumOperands() == 0) {
llvm::Value *string = llvm::MDString::get(getLLVMContext(), assembly);
metadata->addOperand(llvm::MDNode::get(getLLVMContext(), string));
}
}
}
// Call the marker asm if we made one, which we do only at -O0.
if (marker) Builder.CreateCall(marker);
return emitARCValueOperation(*this, value,
CGM.getARCEntrypoints().objc_retainAutoreleasedReturnValue,
"objc_retainAutoreleasedReturnValue");
}
/// Release the given object.
/// call void @objc_release(i8* %value)
void CodeGenFunction::EmitARCRelease(llvm::Value *value, bool precise) {
if (isa<llvm::ConstantPointerNull>(value)) return;
llvm::Constant *&fn = CGM.getARCEntrypoints().objc_release;
if (!fn) {
std::vector<llvm::Type*> args(1, Int8PtrTy);
llvm::FunctionType *fnType =
llvm::FunctionType::get(Builder.getVoidTy(), args, false);
fn = createARCRuntimeFunction(CGM, fnType, "objc_release");
}
// Cast the argument to 'id'.
value = Builder.CreateBitCast(value, Int8PtrTy);
// Call objc_release.
llvm::CallInst *call = Builder.CreateCall(fn, value);
call->setDoesNotThrow();
if (!precise) {
SmallVector<llvm::Value*,1> args;
call->setMetadata("clang.imprecise_release",
llvm::MDNode::get(Builder.getContext(), args));
}
}
/// Store into a strong object. Always calls this:
/// call void @objc_storeStrong(i8** %addr, i8* %value)
llvm::Value *CodeGenFunction::EmitARCStoreStrongCall(llvm::Value *addr,
llvm::Value *value,
bool ignored) {
assert(cast<llvm::PointerType>(addr->getType())->getElementType()
== value->getType());
llvm::Constant *&fn = CGM.getARCEntrypoints().objc_storeStrong;
if (!fn) {
llvm::Type *argTypes[] = { Int8PtrPtrTy, Int8PtrTy };
llvm::FunctionType *fnType
= llvm::FunctionType::get(Builder.getVoidTy(), argTypes, false);
fn = createARCRuntimeFunction(CGM, fnType, "objc_storeStrong");
}
addr = Builder.CreateBitCast(addr, Int8PtrPtrTy);
llvm::Value *castValue = Builder.CreateBitCast(value, Int8PtrTy);
Builder.CreateCall2(fn, addr, castValue)->setDoesNotThrow();
if (ignored) return 0;
return value;
}
/// Store into a strong object. Sometimes calls this:
/// call void @objc_storeStrong(i8** %addr, i8* %value)
/// Other times, breaks it down into components.
llvm::Value *CodeGenFunction::EmitARCStoreStrong(LValue dst,
llvm::Value *newValue,
bool ignored) {
QualType type = dst.getType();
bool isBlock = type->isBlockPointerType();
// Use a store barrier at -O0 unless this is a block type or the
// lvalue is inadequately aligned.
if (shouldUseFusedARCCalls() &&
!isBlock &&
!(dst.getAlignment() && dst.getAlignment() < PointerAlignInBytes)) {
return EmitARCStoreStrongCall(dst.getAddress(), newValue, ignored);
}
// Otherwise, split it out.
// Retain the new value.
newValue = EmitARCRetain(type, newValue);
// Read the old value.
llvm::Value *oldValue = EmitLoadOfScalar(dst);
// Store. We do this before the release so that any deallocs won't
// see the old value.
EmitStoreOfScalar(newValue, dst);
// Finally, release the old value.
EmitARCRelease(oldValue, /*precise*/ false);
return newValue;
}
/// Autorelease the given object.
/// call i8* @objc_autorelease(i8* %value)
llvm::Value *CodeGenFunction::EmitARCAutorelease(llvm::Value *value) {
return emitARCValueOperation(*this, value,
CGM.getARCEntrypoints().objc_autorelease,
"objc_autorelease");
}
/// Autorelease the given object.
/// call i8* @objc_autoreleaseReturnValue(i8* %value)
llvm::Value *
CodeGenFunction::EmitARCAutoreleaseReturnValue(llvm::Value *value) {
return emitARCValueOperation(*this, value,
CGM.getARCEntrypoints().objc_autoreleaseReturnValue,
"objc_autoreleaseReturnValue");
}
/// Do a fused retain/autorelease of the given object.
/// call i8* @objc_retainAutoreleaseReturnValue(i8* %value)
llvm::Value *
CodeGenFunction::EmitARCRetainAutoreleaseReturnValue(llvm::Value *value) {
return emitARCValueOperation(*this, value,
CGM.getARCEntrypoints().objc_retainAutoreleaseReturnValue,
"objc_retainAutoreleaseReturnValue");
}
/// Do a fused retain/autorelease of the given object.
/// call i8* @objc_retainAutorelease(i8* %value)
/// or
/// %retain = call i8* @objc_retainBlock(i8* %value)
/// call i8* @objc_autorelease(i8* %retain)
llvm::Value *CodeGenFunction::EmitARCRetainAutorelease(QualType type,
llvm::Value *value) {
if (!type->isBlockPointerType())
return EmitARCRetainAutoreleaseNonBlock(value);
if (isa<llvm::ConstantPointerNull>(value)) return value;
llvm::Type *origType = value->getType();
value = Builder.CreateBitCast(value, Int8PtrTy);
value = EmitARCRetainBlock(value);
value = EmitARCAutorelease(value);
return Builder.CreateBitCast(value, origType);
}
/// Do a fused retain/autorelease of the given object.
/// call i8* @objc_retainAutorelease(i8* %value)
llvm::Value *
CodeGenFunction::EmitARCRetainAutoreleaseNonBlock(llvm::Value *value) {
return emitARCValueOperation(*this, value,
CGM.getARCEntrypoints().objc_retainAutorelease,
"objc_retainAutorelease");
}
/// i8* @objc_loadWeak(i8** %addr)
/// Essentially objc_autorelease(objc_loadWeakRetained(addr)).
llvm::Value *CodeGenFunction::EmitARCLoadWeak(llvm::Value *addr) {
return emitARCLoadOperation(*this, addr,
CGM.getARCEntrypoints().objc_loadWeak,
"objc_loadWeak");
}
/// i8* @objc_loadWeakRetained(i8** %addr)
llvm::Value *CodeGenFunction::EmitARCLoadWeakRetained(llvm::Value *addr) {
return emitARCLoadOperation(*this, addr,
CGM.getARCEntrypoints().objc_loadWeakRetained,
"objc_loadWeakRetained");
}
/// i8* @objc_storeWeak(i8** %addr, i8* %value)
/// Returns %value.
llvm::Value *CodeGenFunction::EmitARCStoreWeak(llvm::Value *addr,
llvm::Value *value,
bool ignored) {
return emitARCStoreOperation(*this, addr, value,
CGM.getARCEntrypoints().objc_storeWeak,
"objc_storeWeak", ignored);
}
/// i8* @objc_initWeak(i8** %addr, i8* %value)
/// Returns %value. %addr is known to not have a current weak entry.
/// Essentially equivalent to:
/// *addr = nil; objc_storeWeak(addr, value);
void CodeGenFunction::EmitARCInitWeak(llvm::Value *addr, llvm::Value *value) {
// If we're initializing to null, just write null to memory; no need
// to get the runtime involved. But don't do this if optimization
// is enabled, because accounting for this would make the optimizer
// much more complicated.
if (isa<llvm::ConstantPointerNull>(value) &&
CGM.getCodeGenOpts().OptimizationLevel == 0) {
Builder.CreateStore(value, addr);
return;
}
emitARCStoreOperation(*this, addr, value,
CGM.getARCEntrypoints().objc_initWeak,
"objc_initWeak", /*ignored*/ true);
}
/// void @objc_destroyWeak(i8** %addr)
/// Essentially objc_storeWeak(addr, nil).
void CodeGenFunction::EmitARCDestroyWeak(llvm::Value *addr) {
llvm::Constant *&fn = CGM.getARCEntrypoints().objc_destroyWeak;
if (!fn) {
std::vector<llvm::Type*> args(1, Int8PtrPtrTy);
llvm::FunctionType *fnType =
llvm::FunctionType::get(Builder.getVoidTy(), args, false);
fn = createARCRuntimeFunction(CGM, fnType, "objc_destroyWeak");
}
// Cast the argument to 'id*'.
addr = Builder.CreateBitCast(addr, Int8PtrPtrTy);
llvm::CallInst *call = Builder.CreateCall(fn, addr);
call->setDoesNotThrow();
}
/// void @objc_moveWeak(i8** %dest, i8** %src)
/// Disregards the current value in %dest. Leaves %src pointing to nothing.
/// Essentially (objc_copyWeak(dest, src), objc_destroyWeak(src)).
void CodeGenFunction::EmitARCMoveWeak(llvm::Value *dst, llvm::Value *src) {
emitARCCopyOperation(*this, dst, src,
CGM.getARCEntrypoints().objc_moveWeak,
"objc_moveWeak");
}
/// void @objc_copyWeak(i8** %dest, i8** %src)
/// Disregards the current value in %dest. Essentially
/// objc_release(objc_initWeak(dest, objc_readWeakRetained(src)))
void CodeGenFunction::EmitARCCopyWeak(llvm::Value *dst, llvm::Value *src) {
emitARCCopyOperation(*this, dst, src,
CGM.getARCEntrypoints().objc_copyWeak,
"objc_copyWeak");
}
/// Produce the code to do a objc_autoreleasepool_push.
/// call i8* @objc_autoreleasePoolPush(void)
llvm::Value *CodeGenFunction::EmitObjCAutoreleasePoolPush() {
llvm::Constant *&fn = CGM.getRREntrypoints().objc_autoreleasePoolPush;
if (!fn) {
llvm::FunctionType *fnType =
llvm::FunctionType::get(Int8PtrTy, false);
fn = createARCRuntimeFunction(CGM, fnType, "objc_autoreleasePoolPush");
}
llvm::CallInst *call = Builder.CreateCall(fn);
call->setDoesNotThrow();
return call;
}
/// Produce the code to do a primitive release.
/// call void @objc_autoreleasePoolPop(i8* %ptr)
void CodeGenFunction::EmitObjCAutoreleasePoolPop(llvm::Value *value) {
assert(value->getType() == Int8PtrTy);
llvm::Constant *&fn = CGM.getRREntrypoints().objc_autoreleasePoolPop;
if (!fn) {
std::vector<llvm::Type*> args(1, Int8PtrTy);
llvm::FunctionType *fnType =
llvm::FunctionType::get(Builder.getVoidTy(), args, false);
// We don't want to use a weak import here; instead we should not
// fall into this path.
fn = createARCRuntimeFunction(CGM, fnType, "objc_autoreleasePoolPop");
}
llvm::CallInst *call = Builder.CreateCall(fn, value);
call->setDoesNotThrow();
}
/// Produce the code to do an MRR version objc_autoreleasepool_push.
/// Which is: [[NSAutoreleasePool alloc] init];
/// Where alloc is declared as: + (id) alloc; in NSAutoreleasePool class.
/// init is declared as: - (id) init; in its NSObject super class.
///
llvm::Value *CodeGenFunction::EmitObjCMRRAutoreleasePoolPush() {
CGObjCRuntime &Runtime = CGM.getObjCRuntime();
llvm::Value *Receiver = Runtime.EmitNSAutoreleasePoolClassRef(Builder);
// [NSAutoreleasePool alloc]
IdentifierInfo *II = &CGM.getContext().Idents.get("alloc");
Selector AllocSel = getContext().Selectors.getSelector(0, &II);
CallArgList Args;
RValue AllocRV =
Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
getContext().getObjCIdType(),
AllocSel, Receiver, Args);
// [Receiver init]
Receiver = AllocRV.getScalarVal();
II = &CGM.getContext().Idents.get("init");
Selector InitSel = getContext().Selectors.getSelector(0, &II);
RValue InitRV =
Runtime.GenerateMessageSend(*this, ReturnValueSlot(),
getContext().getObjCIdType(),
InitSel, Receiver, Args);
return InitRV.getScalarVal();
}
/// Produce the code to do a primitive release.
/// [tmp drain];
void CodeGenFunction::EmitObjCMRRAutoreleasePoolPop(llvm::Value *Arg) {
IdentifierInfo *II = &CGM.getContext().Idents.get("drain");
Selector DrainSel = getContext().Selectors.getSelector(0, &II);
CallArgList Args;
CGM.getObjCRuntime().GenerateMessageSend(*this, ReturnValueSlot(),
getContext().VoidTy, DrainSel, Arg, Args);
}
void CodeGenFunction::destroyARCStrongPrecise(CodeGenFunction &CGF,
llvm::Value *addr,
QualType type) {
llvm::Value *ptr = CGF.Builder.CreateLoad(addr, "strongdestroy");
CGF.EmitARCRelease(ptr, /*precise*/ true);
}
void CodeGenFunction::destroyARCStrongImprecise(CodeGenFunction &CGF,
llvm::Value *addr,
QualType type) {
llvm::Value *ptr = CGF.Builder.CreateLoad(addr, "strongdestroy");
CGF.EmitARCRelease(ptr, /*precise*/ false);
}
void CodeGenFunction::destroyARCWeak(CodeGenFunction &CGF,
llvm::Value *addr,
QualType type) {
CGF.EmitARCDestroyWeak(addr);
}
namespace {
struct CallObjCAutoreleasePoolObject : EHScopeStack::Cleanup {
llvm::Value *Token;
CallObjCAutoreleasePoolObject(llvm::Value *token) : Token(token) {}
void Emit(CodeGenFunction &CGF, Flags flags) {
CGF.EmitObjCAutoreleasePoolPop(Token);
}
};
struct CallObjCMRRAutoreleasePoolObject : EHScopeStack::Cleanup {
llvm::Value *Token;
CallObjCMRRAutoreleasePoolObject(llvm::Value *token) : Token(token) {}
void Emit(CodeGenFunction &CGF, Flags flags) {
CGF.EmitObjCMRRAutoreleasePoolPop(Token);
}
};
}
void CodeGenFunction::EmitObjCAutoreleasePoolCleanup(llvm::Value *Ptr) {
if (CGM.getLangOptions().ObjCAutoRefCount)
EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, Ptr);
else
EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, Ptr);
}
static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF,
LValue lvalue,
QualType type) {
switch (type.getObjCLifetime()) {
case Qualifiers::OCL_None:
case Qualifiers::OCL_ExplicitNone:
case Qualifiers::OCL_Strong:
case Qualifiers::OCL_Autoreleasing:
return TryEmitResult(CGF.EmitLoadOfLValue(lvalue).getScalarVal(),
false);
case Qualifiers::OCL_Weak:
return TryEmitResult(CGF.EmitARCLoadWeakRetained(lvalue.getAddress()),
true);
}
llvm_unreachable("impossible lifetime!");
return TryEmitResult();
}
static TryEmitResult tryEmitARCRetainLoadOfScalar(CodeGenFunction &CGF,
const Expr *e) {
e = e->IgnoreParens();
QualType type = e->getType();
// As a very special optimization, in ARC++, if the l-value is the
// result of a non-volatile assignment, do a simple retain of the
// result of the call to objc_storeWeak instead of reloading.
if (CGF.getLangOptions().CPlusPlus &&
!type.isVolatileQualified() &&
type.getObjCLifetime() == Qualifiers::OCL_Weak &&
isa<BinaryOperator>(e) &&
cast<BinaryOperator>(e)->getOpcode() == BO_Assign)
return TryEmitResult(CGF.EmitScalarExpr(e), false);
return tryEmitARCRetainLoadOfScalar(CGF, CGF.EmitLValue(e), type);
}
static llvm::Value *emitARCRetainAfterCall(CodeGenFunction &CGF,
llvm::Value *value);
/// Given that the given expression is some sort of call (which does
/// not return retained), emit a retain following it.
static llvm::Value *emitARCRetainCall(CodeGenFunction &CGF, const Expr *e) {
llvm::Value *value = CGF.EmitScalarExpr(e);
return emitARCRetainAfterCall(CGF, value);
}
static llvm::Value *emitARCRetainAfterCall(CodeGenFunction &CGF,
llvm::Value *value) {
if (llvm::CallInst *call = dyn_cast<llvm::CallInst>(value)) {
CGBuilderTy::InsertPoint ip = CGF.Builder.saveIP();
// Place the retain immediately following the call.
CGF.Builder.SetInsertPoint(call->getParent(),
++llvm::BasicBlock::iterator(call));
value = CGF.EmitARCRetainAutoreleasedReturnValue(value);
CGF.Builder.restoreIP(ip);
return value;
} else if (llvm::InvokeInst *invoke = dyn_cast<llvm::InvokeInst>(value)) {
CGBuilderTy::InsertPoint ip = CGF.Builder.saveIP();
// Place the retain at the beginning of the normal destination block.
llvm::BasicBlock *BB = invoke->getNormalDest();
CGF.Builder.SetInsertPoint(BB, BB->begin());
value = CGF.EmitARCRetainAutoreleasedReturnValue(value);
CGF.Builder.restoreIP(ip);
return value;
// Bitcasts can arise because of related-result returns. Rewrite
// the operand.
} else if (llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(value)) {
llvm::Value *operand = bitcast->getOperand(0);
operand = emitARCRetainAfterCall(CGF, operand);
bitcast->setOperand(0, operand);
return bitcast;
// Generic fall-back case.
} else {
// Retain using the non-block variant: we never need to do a copy
// of a block that's been returned to us.
return CGF.EmitARCRetainNonBlock(value);
}
}
static TryEmitResult
tryEmitARCRetainScalarExpr(CodeGenFunction &CGF, const Expr *e) {
// Look through cleanups.
if (const ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(e)) {
CodeGenFunction::RunCleanupsScope scope(CGF);
return tryEmitARCRetainScalarExpr(CGF, cleanups->getSubExpr());
}
// The desired result type, if it differs from the type of the
// ultimate opaque expression.
llvm::Type *resultType = 0;
// If we're loading retained from a __strong xvalue, we can avoid
// an extra retain/release pair by zeroing out the source of this
// "move" operation.
if (e->isXValue() && !e->getType().isConstQualified() &&
e->getType().getObjCLifetime() == Qualifiers::OCL_Strong) {
// Emit the lvalue
LValue lv = CGF.EmitLValue(e);
// Load the object pointer and cast it to the appropriate type.
QualType exprType = e->getType();
llvm::Value *result = CGF.EmitLoadOfLValue(lv).getScalarVal();
if (resultType)
result = CGF.Builder.CreateBitCast(result, resultType);
// Set the source pointer to NULL.
llvm::Value *null
= llvm::ConstantPointerNull::get(
cast<llvm::PointerType>(CGF.ConvertType(exprType)));
CGF.EmitStoreOfScalar(null, lv);
return TryEmitResult(result, true);
}
while (true) {
e = e->IgnoreParens();
// There's a break at the end of this if-chain; anything
// that wants to keep looping has to explicitly continue.
if (const CastExpr *ce = dyn_cast<CastExpr>(e)) {
switch (ce->getCastKind()) {
// No-op casts don't change the type, so we just ignore them.
case CK_NoOp:
e = ce->getSubExpr();
continue;
case CK_LValueToRValue: {
TryEmitResult loadResult
= tryEmitARCRetainLoadOfScalar(CGF, ce->getSubExpr());
if (resultType) {
llvm::Value *value = loadResult.getPointer();
value = CGF.Builder.CreateBitCast(value, resultType);
loadResult.setPointer(value);
}
return loadResult;
}
// These casts can change the type, so remember that and
// soldier on. We only need to remember the outermost such
// cast, though.
case CK_AnyPointerToObjCPointerCast:
case CK_AnyPointerToBlockPointerCast:
case CK_BitCast:
if (!resultType)
resultType = CGF.ConvertType(ce->getType());
e = ce->getSubExpr();
assert(e->getType()->hasPointerRepresentation());
continue;
// For consumptions, just emit the subexpression and thus elide
// the retain/release pair.
case CK_ObjCConsumeObject: {
llvm::Value *result = CGF.EmitScalarExpr(ce->getSubExpr());
if (resultType) result = CGF.Builder.CreateBitCast(result, resultType);
return TryEmitResult(result, true);
}
// For reclaims, emit the subexpression as a retained call and
// skip the consumption.
case CK_ObjCReclaimReturnedObject: {
llvm::Value *result = emitARCRetainCall(CGF, ce->getSubExpr());
if (resultType) result = CGF.Builder.CreateBitCast(result, resultType);
return TryEmitResult(result, true);
}
case CK_GetObjCProperty: {
llvm::Value *result = emitARCRetainCall(CGF, ce);
if (resultType) result = CGF.Builder.CreateBitCast(result, resultType);
return TryEmitResult(result, true);
}
default:
break;
}
// Skip __extension__.
} else if (const UnaryOperator *op = dyn_cast<UnaryOperator>(e)) {
if (op->getOpcode() == UO_Extension) {
e = op->getSubExpr();
continue;
}
// For calls and message sends, use the retained-call logic.
// Delegate inits are a special case in that they're the only
// returns-retained expression that *isn't* surrounded by
// a consume.
} else if (isa<CallExpr>(e) ||
(isa<ObjCMessageExpr>(e) &&
!cast<ObjCMessageExpr>(e)->isDelegateInitCall())) {
llvm::Value *result = emitARCRetainCall(CGF, e);
if (resultType) result = CGF.Builder.CreateBitCast(result, resultType);
return TryEmitResult(result, true);
}
// Conservatively halt the search at any other expression kind.
break;
}
// We didn't find an obvious production, so emit what we've got and
// tell the caller that we didn't manage to retain.
llvm::Value *result = CGF.EmitScalarExpr(e);
if (resultType) result = CGF.Builder.CreateBitCast(result, resultType);
return TryEmitResult(result, false);
}
static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF,
LValue lvalue,
QualType type) {
TryEmitResult result = tryEmitARCRetainLoadOfScalar(CGF, lvalue, type);
llvm::Value *value = result.getPointer();
if (!result.getInt())
value = CGF.EmitARCRetain(type, value);
return value;
}
/// EmitARCRetainScalarExpr - Semantically equivalent to
/// EmitARCRetainObject(e->getType(), EmitScalarExpr(e)), but making a
/// best-effort attempt to peephole expressions that naturally produce
/// retained objects.
llvm::Value *CodeGenFunction::EmitARCRetainScalarExpr(const Expr *e) {
TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e);
llvm::Value *value = result.getPointer();
if (!result.getInt())
value = EmitARCRetain(e->getType(), value);
return value;
}
llvm::Value *
CodeGenFunction::EmitARCRetainAutoreleaseScalarExpr(const Expr *e) {
TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e);
llvm::Value *value = result.getPointer();
if (result.getInt())
value = EmitARCAutorelease(value);
else
value = EmitARCRetainAutorelease(e->getType(), value);
return value;
}
std::pair<LValue,llvm::Value*>
CodeGenFunction::EmitARCStoreStrong(const BinaryOperator *e,
bool ignored) {
// Evaluate the RHS first.
TryEmitResult result = tryEmitARCRetainScalarExpr(*this, e->getRHS());
llvm::Value *value = result.getPointer();
bool hasImmediateRetain = result.getInt();
// If we didn't emit a retained object, and the l-value is of block
// type, then we need to emit the block-retain immediately in case
// it invalidates the l-value.
if (!hasImmediateRetain && e->getType()->isBlockPointerType()) {
value = EmitARCRetainBlock(value);
hasImmediateRetain = true;
}
LValue lvalue = EmitLValue(e->getLHS());
// If the RHS was emitted retained, expand this.
if (hasImmediateRetain) {
llvm::Value *oldValue =
EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatileQualified(),
lvalue.getAlignment(), e->getType(),
lvalue.getTBAAInfo());
EmitStoreOfScalar(value, lvalue.getAddress(),
lvalue.isVolatileQualified(), lvalue.getAlignment(),
e->getType(), lvalue.getTBAAInfo());
EmitARCRelease(oldValue, /*precise*/ false);
} else {
value = EmitARCStoreStrong(lvalue, value, ignored);
}
return std::pair<LValue,llvm::Value*>(lvalue, value);
}
std::pair<LValue,llvm::Value*>
CodeGenFunction::EmitARCStoreAutoreleasing(const BinaryOperator *e) {
llvm::Value *value = EmitARCRetainAutoreleaseScalarExpr(e->getRHS());
LValue lvalue = EmitLValue(e->getLHS());
EmitStoreOfScalar(value, lvalue.getAddress(),
lvalue.isVolatileQualified(), lvalue.getAlignment(),
e->getType(), lvalue.getTBAAInfo());
return std::pair<LValue,llvm::Value*>(lvalue, value);
}
void CodeGenFunction::EmitObjCAutoreleasePoolStmt(
const ObjCAutoreleasePoolStmt &ARPS) {
const Stmt *subStmt = ARPS.getSubStmt();
const CompoundStmt &S = cast<CompoundStmt>(*subStmt);
CGDebugInfo *DI = getDebugInfo();
if (DI) {
DI->setLocation(S.getLBracLoc());
DI->EmitRegionStart(Builder);
}
// Keep track of the current cleanup stack depth.
RunCleanupsScope Scope(*this);
if (CGM.getCodeGenOpts().ObjCRuntimeHasARC) {
llvm::Value *token = EmitObjCAutoreleasePoolPush();
EHStack.pushCleanup<CallObjCAutoreleasePoolObject>(NormalCleanup, token);
} else {
llvm::Value *token = EmitObjCMRRAutoreleasePoolPush();
EHStack.pushCleanup<CallObjCMRRAutoreleasePoolObject>(NormalCleanup, token);
}
for (CompoundStmt::const_body_iterator I = S.body_begin(),
E = S.body_end(); I != E; ++I)
EmitStmt(*I);
if (DI) {
DI->setLocation(S.getRBracLoc());
DI->EmitRegionEnd(Builder);
}
}
/// EmitExtendGCLifetime - Given a pointer to an Objective-C object,
/// make sure it survives garbage collection until this point.
void CodeGenFunction::EmitExtendGCLifetime(llvm::Value *object) {
// We just use an inline assembly.
llvm::FunctionType *extenderType
= llvm::FunctionType::get(VoidTy, VoidPtrTy, /*variadic*/ false);
llvm::Value *extender
= llvm::InlineAsm::get(extenderType,
/* assembly */ "",
/* constraints */ "r",
/* side effects */ true);
object = Builder.CreateBitCast(object, VoidPtrTy);
Builder.CreateCall(extender, object)->setDoesNotThrow();
}
CGObjCRuntime::~CGObjCRuntime() {}
Reference in New Issue View Git Blame Copy Permalink