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Diffstat (limited to 'contrib/llvm/tools/clang/lib/CodeGen/CGExpr.cpp')
| -rw-r--r-- | contrib/llvm/tools/clang/lib/CodeGen/CGExpr.cpp | 2175 |
1 files changed, 2175 insertions, 0 deletions
diff --git a/contrib/llvm/tools/clang/lib/CodeGen/CGExpr.cpp b/contrib/llvm/tools/clang/lib/CodeGen/CGExpr.cpp new file mode 100644 index 0000000..bc2cd35 --- /dev/null +++ b/contrib/llvm/tools/clang/lib/CodeGen/CGExpr.cpp @@ -0,0 +1,2175 @@ +//===--- CGExpr.cpp - Emit LLVM Code from Expressions ---------------------===// +// +// 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 Expr nodes as LLVM code. +// +//===----------------------------------------------------------------------===// + +#include "CodeGenFunction.h" +#include "CodeGenModule.h" +#include "CGCall.h" +#include "CGCXXABI.h" +#include "CGDebugInfo.h" +#include "CGRecordLayout.h" +#include "CGObjCRuntime.h" +#include "clang/AST/ASTContext.h" +#include "clang/AST/DeclObjC.h" +#include "llvm/Intrinsics.h" +#include "clang/Frontend/CodeGenOptions.h" +#include "llvm/Target/TargetData.h" +using namespace clang; +using namespace CodeGen; + +//===--------------------------------------------------------------------===// +// Miscellaneous Helper Methods +//===--------------------------------------------------------------------===// + +llvm::Value *CodeGenFunction::EmitCastToVoidPtr(llvm::Value *value) { + unsigned addressSpace = + cast<llvm::PointerType>(value->getType())->getAddressSpace(); + + const llvm::PointerType *destType = Int8PtrTy; + if (addressSpace) + destType = llvm::Type::getInt8PtrTy(getLLVMContext(), addressSpace); + + if (value->getType() == destType) return value; + return Builder.CreateBitCast(value, destType); +} + +/// CreateTempAlloca - This creates a alloca and inserts it into the entry +/// block. +llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(const llvm::Type *Ty, + const llvm::Twine &Name) { + if (!Builder.isNamePreserving()) + return new llvm::AllocaInst(Ty, 0, "", AllocaInsertPt); + return new llvm::AllocaInst(Ty, 0, Name, AllocaInsertPt); +} + +void CodeGenFunction::InitTempAlloca(llvm::AllocaInst *Var, + llvm::Value *Init) { + llvm::StoreInst *Store = new llvm::StoreInst(Init, Var); + llvm::BasicBlock *Block = AllocaInsertPt->getParent(); + Block->getInstList().insertAfter(&*AllocaInsertPt, Store); +} + +llvm::AllocaInst *CodeGenFunction::CreateIRTemp(QualType Ty, + const llvm::Twine &Name) { + llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertType(Ty), Name); + // FIXME: Should we prefer the preferred type alignment here? + CharUnits Align = getContext().getTypeAlignInChars(Ty); + Alloc->setAlignment(Align.getQuantity()); + return Alloc; +} + +llvm::AllocaInst *CodeGenFunction::CreateMemTemp(QualType Ty, + const llvm::Twine &Name) { + llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertTypeForMem(Ty), Name); + // FIXME: Should we prefer the preferred type alignment here? + CharUnits Align = getContext().getTypeAlignInChars(Ty); + Alloc->setAlignment(Align.getQuantity()); + return Alloc; +} + +/// EvaluateExprAsBool - Perform the usual unary conversions on the specified +/// expression and compare the result against zero, returning an Int1Ty value. +llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) { + if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) { + llvm::Value *MemPtr = EmitScalarExpr(E); + return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT); + } + + QualType BoolTy = getContext().BoolTy; + if (!E->getType()->isAnyComplexType()) + return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy); + + return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(),BoolTy); +} + +/// EmitIgnoredExpr - Emit code to compute the specified expression, +/// ignoring the result. +void CodeGenFunction::EmitIgnoredExpr(const Expr *E) { + if (E->isRValue()) + return (void) EmitAnyExpr(E, AggValueSlot::ignored(), true); + + // Just emit it as an l-value and drop the result. + EmitLValue(E); +} + +/// EmitAnyExpr - Emit code to compute the specified expression which +/// can have any type. The result is returned as an RValue struct. +/// If this is an aggregate expression, AggSlot indicates where the +/// result should be returned. +RValue CodeGenFunction::EmitAnyExpr(const Expr *E, AggValueSlot AggSlot, + bool IgnoreResult) { + if (!hasAggregateLLVMType(E->getType())) + return RValue::get(EmitScalarExpr(E, IgnoreResult)); + else if (E->getType()->isAnyComplexType()) + return RValue::getComplex(EmitComplexExpr(E, IgnoreResult, IgnoreResult)); + + EmitAggExpr(E, AggSlot, IgnoreResult); + return AggSlot.asRValue(); +} + +/// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will +/// always be accessible even if no aggregate location is provided. +RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) { + AggValueSlot AggSlot = AggValueSlot::ignored(); + + if (hasAggregateLLVMType(E->getType()) && + !E->getType()->isAnyComplexType()) + AggSlot = CreateAggTemp(E->getType(), "agg.tmp"); + return EmitAnyExpr(E, AggSlot); +} + +/// EmitAnyExprToMem - Evaluate an expression into a given memory +/// location. +void CodeGenFunction::EmitAnyExprToMem(const Expr *E, + llvm::Value *Location, + bool IsLocationVolatile, + bool IsInit) { + if (E->getType()->isComplexType()) + EmitComplexExprIntoAddr(E, Location, IsLocationVolatile); + else if (hasAggregateLLVMType(E->getType())) + EmitAggExpr(E, AggValueSlot::forAddr(Location, IsLocationVolatile, IsInit)); + else { + RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false)); + LValue LV = MakeAddrLValue(Location, E->getType()); + EmitStoreThroughLValue(RV, LV, E->getType()); + } +} + +namespace { +/// \brief An adjustment to be made to the temporary created when emitting a +/// reference binding, which accesses a particular subobject of that temporary. + struct SubobjectAdjustment { + enum { DerivedToBaseAdjustment, FieldAdjustment } Kind; + + union { + struct { + const CastExpr *BasePath; + const CXXRecordDecl *DerivedClass; + } DerivedToBase; + + FieldDecl *Field; + }; + + SubobjectAdjustment(const CastExpr *BasePath, + const CXXRecordDecl *DerivedClass) + : Kind(DerivedToBaseAdjustment) { + DerivedToBase.BasePath = BasePath; + DerivedToBase.DerivedClass = DerivedClass; + } + + SubobjectAdjustment(FieldDecl *Field) + : Kind(FieldAdjustment) { + this->Field = Field; + } + }; +} + +static llvm::Value * +CreateReferenceTemporary(CodeGenFunction& CGF, QualType Type, + const NamedDecl *InitializedDecl) { + if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(InitializedDecl)) { + if (VD->hasGlobalStorage()) { + llvm::SmallString<256> Name; + llvm::raw_svector_ostream Out(Name); + CGF.CGM.getCXXABI().getMangleContext().mangleReferenceTemporary(VD, Out); + Out.flush(); + + const llvm::Type *RefTempTy = CGF.ConvertTypeForMem(Type); + + // Create the reference temporary. + llvm::GlobalValue *RefTemp = + new llvm::GlobalVariable(CGF.CGM.getModule(), + RefTempTy, /*isConstant=*/false, + llvm::GlobalValue::InternalLinkage, + llvm::Constant::getNullValue(RefTempTy), + Name.str()); + return RefTemp; + } + } + + return CGF.CreateMemTemp(Type, "ref.tmp"); +} + +static llvm::Value * +EmitExprForReferenceBinding(CodeGenFunction &CGF, const Expr *E, + llvm::Value *&ReferenceTemporary, + const CXXDestructorDecl *&ReferenceTemporaryDtor, + const NamedDecl *InitializedDecl) { + if (const CXXDefaultArgExpr *DAE = dyn_cast<CXXDefaultArgExpr>(E)) + E = DAE->getExpr(); + + if (const ExprWithCleanups *TE = dyn_cast<ExprWithCleanups>(E)) { + CodeGenFunction::RunCleanupsScope Scope(CGF); + + return EmitExprForReferenceBinding(CGF, TE->getSubExpr(), + ReferenceTemporary, + ReferenceTemporaryDtor, + InitializedDecl); + } + + if (const ObjCPropertyRefExpr *PRE = + dyn_cast<ObjCPropertyRefExpr>(E->IgnoreParenImpCasts())) + if (PRE->getGetterResultType()->isReferenceType()) + E = PRE; + + RValue RV; + if (E->isGLValue()) { + // Emit the expression as an lvalue. + LValue LV = CGF.EmitLValue(E); + if (LV.isPropertyRef()) { + RV = CGF.EmitLoadOfPropertyRefLValue(LV); + return RV.getScalarVal(); + } + if (LV.isSimple()) + return LV.getAddress(); + + // We have to load the lvalue. + RV = CGF.EmitLoadOfLValue(LV, E->getType()); + } else { + llvm::SmallVector<SubobjectAdjustment, 2> Adjustments; + while (true) { + E = E->IgnoreParens(); + + if (const CastExpr *CE = dyn_cast<CastExpr>(E)) { + if ((CE->getCastKind() == CK_DerivedToBase || + CE->getCastKind() == CK_UncheckedDerivedToBase) && + E->getType()->isRecordType()) { + E = CE->getSubExpr(); + CXXRecordDecl *Derived + = cast<CXXRecordDecl>(E->getType()->getAs<RecordType>()->getDecl()); + Adjustments.push_back(SubobjectAdjustment(CE, Derived)); + continue; + } + + if (CE->getCastKind() == CK_NoOp) { + E = CE->getSubExpr(); + continue; + } + } else if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) { + if (!ME->isArrow() && ME->getBase()->isRValue()) { + assert(ME->getBase()->getType()->isRecordType()); + if (FieldDecl *Field = dyn_cast<FieldDecl>(ME->getMemberDecl())) { + E = ME->getBase(); + Adjustments.push_back(SubobjectAdjustment(Field)); + continue; + } + } + } + + if (const OpaqueValueExpr *opaque = dyn_cast<OpaqueValueExpr>(E)) + if (opaque->getType()->isRecordType()) + return CGF.EmitOpaqueValueLValue(opaque).getAddress(); + + // Nothing changed. + break; + } + + // Create a reference temporary if necessary. + AggValueSlot AggSlot = AggValueSlot::ignored(); + if (CGF.hasAggregateLLVMType(E->getType()) && + !E->getType()->isAnyComplexType()) { + ReferenceTemporary = CreateReferenceTemporary(CGF, E->getType(), + InitializedDecl); + AggSlot = AggValueSlot::forAddr(ReferenceTemporary, false, + InitializedDecl != 0); + } + + RV = CGF.EmitAnyExpr(E, AggSlot); + + if (InitializedDecl) { + // Get the destructor for the reference temporary. + if (const RecordType *RT = E->getType()->getAs<RecordType>()) { + CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RT->getDecl()); + if (!ClassDecl->hasTrivialDestructor()) + ReferenceTemporaryDtor = ClassDecl->getDestructor(); + } + } + + // Check if need to perform derived-to-base casts and/or field accesses, to + // get from the temporary object we created (and, potentially, for which we + // extended the lifetime) to the subobject we're binding the reference to. + if (!Adjustments.empty()) { + llvm::Value *Object = RV.getAggregateAddr(); + for (unsigned I = Adjustments.size(); I != 0; --I) { + SubobjectAdjustment &Adjustment = Adjustments[I-1]; + switch (Adjustment.Kind) { + case SubobjectAdjustment::DerivedToBaseAdjustment: + Object = + CGF.GetAddressOfBaseClass(Object, + Adjustment.DerivedToBase.DerivedClass, + Adjustment.DerivedToBase.BasePath->path_begin(), + Adjustment.DerivedToBase.BasePath->path_end(), + /*NullCheckValue=*/false); + break; + + case SubobjectAdjustment::FieldAdjustment: { + LValue LV = + CGF.EmitLValueForField(Object, Adjustment.Field, 0); + if (LV.isSimple()) { + Object = LV.getAddress(); + break; + } + + // For non-simple lvalues, we actually have to create a copy of + // the object we're binding to. + QualType T = Adjustment.Field->getType().getNonReferenceType() + .getUnqualifiedType(); + Object = CreateReferenceTemporary(CGF, T, InitializedDecl); + LValue TempLV = CGF.MakeAddrLValue(Object, + Adjustment.Field->getType()); + CGF.EmitStoreThroughLValue(CGF.EmitLoadOfLValue(LV, T), TempLV, T); + break; + } + + } + } + + return Object; + } + } + + if (RV.isAggregate()) + return RV.getAggregateAddr(); + + // Create a temporary variable that we can bind the reference to. + ReferenceTemporary = CreateReferenceTemporary(CGF, E->getType(), + InitializedDecl); + + + unsigned Alignment = + CGF.getContext().getTypeAlignInChars(E->getType()).getQuantity(); + if (RV.isScalar()) + CGF.EmitStoreOfScalar(RV.getScalarVal(), ReferenceTemporary, + /*Volatile=*/false, Alignment, E->getType()); + else + CGF.StoreComplexToAddr(RV.getComplexVal(), ReferenceTemporary, + /*Volatile=*/false); + return ReferenceTemporary; +} + +RValue +CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E, + const NamedDecl *InitializedDecl) { + llvm::Value *ReferenceTemporary = 0; + const CXXDestructorDecl *ReferenceTemporaryDtor = 0; + llvm::Value *Value = EmitExprForReferenceBinding(*this, E, ReferenceTemporary, + ReferenceTemporaryDtor, + InitializedDecl); + if (!ReferenceTemporaryDtor) + return RValue::get(Value); + + // Make sure to call the destructor for the reference temporary. + if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(InitializedDecl)) { + if (VD->hasGlobalStorage()) { + llvm::Constant *DtorFn = + CGM.GetAddrOfCXXDestructor(ReferenceTemporaryDtor, Dtor_Complete); + EmitCXXGlobalDtorRegistration(DtorFn, + cast<llvm::Constant>(ReferenceTemporary)); + + return RValue::get(Value); + } + } + + PushDestructorCleanup(ReferenceTemporaryDtor, ReferenceTemporary); + + return RValue::get(Value); +} + + +/// getAccessedFieldNo - Given an encoded value and a result number, return the +/// input field number being accessed. +unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx, + const llvm::Constant *Elts) { + if (isa<llvm::ConstantAggregateZero>(Elts)) + return 0; + + return cast<llvm::ConstantInt>(Elts->getOperand(Idx))->getZExtValue(); +} + +void CodeGenFunction::EmitCheck(llvm::Value *Address, unsigned Size) { + if (!CatchUndefined) + return; + + // This needs to be to the standard address space. + Address = Builder.CreateBitCast(Address, Int8PtrTy); + + const llvm::Type *IntPtrT = IntPtrTy; + llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, &IntPtrT, 1); + + // In time, people may want to control this and use a 1 here. + llvm::Value *Arg = Builder.getFalse(); + llvm::Value *C = Builder.CreateCall2(F, Address, Arg); + llvm::BasicBlock *Cont = createBasicBlock(); + llvm::BasicBlock *Check = createBasicBlock(); + llvm::Value *NegativeOne = llvm::ConstantInt::get(IntPtrTy, -1ULL); + Builder.CreateCondBr(Builder.CreateICmpEQ(C, NegativeOne), Cont, Check); + + EmitBlock(Check); + Builder.CreateCondBr(Builder.CreateICmpUGE(C, + llvm::ConstantInt::get(IntPtrTy, Size)), + Cont, getTrapBB()); + EmitBlock(Cont); +} + + +CodeGenFunction::ComplexPairTy CodeGenFunction:: +EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV, + bool isInc, bool isPre) { + ComplexPairTy InVal = LoadComplexFromAddr(LV.getAddress(), + LV.isVolatileQualified()); + + llvm::Value *NextVal; + if (isa<llvm::IntegerType>(InVal.first->getType())) { + uint64_t AmountVal = isInc ? 1 : -1; + NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true); + + // Add the inc/dec to the real part. + NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec"); + } else { + QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType(); + llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1); + if (!isInc) + FVal.changeSign(); + NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal); + + // Add the inc/dec to the real part. + NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec"); + } + + ComplexPairTy IncVal(NextVal, InVal.second); + + // Store the updated result through the lvalue. + StoreComplexToAddr(IncVal, LV.getAddress(), LV.isVolatileQualified()); + + // If this is a postinc, return the value read from memory, otherwise use the + // updated value. + return isPre ? IncVal : InVal; +} + + +//===----------------------------------------------------------------------===// +// LValue Expression Emission +//===----------------------------------------------------------------------===// + +RValue CodeGenFunction::GetUndefRValue(QualType Ty) { + if (Ty->isVoidType()) + return RValue::get(0); + + if (const ComplexType *CTy = Ty->getAs<ComplexType>()) { + const llvm::Type *EltTy = ConvertType(CTy->getElementType()); + llvm::Value *U = llvm::UndefValue::get(EltTy); + return RValue::getComplex(std::make_pair(U, U)); + } + + // If this is a use of an undefined aggregate type, the aggregate must have an + // identifiable address. Just because the contents of the value are undefined + // doesn't mean that the address can't be taken and compared. + if (hasAggregateLLVMType(Ty)) { + llvm::Value *DestPtr = CreateMemTemp(Ty, "undef.agg.tmp"); + return RValue::getAggregate(DestPtr); + } + + return RValue::get(llvm::UndefValue::get(ConvertType(Ty))); +} + +RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E, + const char *Name) { + ErrorUnsupported(E, Name); + return GetUndefRValue(E->getType()); +} + +LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E, + const char *Name) { + ErrorUnsupported(E, Name); + llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType())); + return MakeAddrLValue(llvm::UndefValue::get(Ty), E->getType()); +} + +LValue CodeGenFunction::EmitCheckedLValue(const Expr *E) { + LValue LV = EmitLValue(E); + if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) + EmitCheck(LV.getAddress(), + getContext().getTypeSizeInChars(E->getType()).getQuantity()); + return LV; +} + +/// EmitLValue - Emit code to compute a designator that specifies the location +/// of the expression. +/// +/// This can return one of two things: a simple address or a bitfield reference. +/// In either case, the LLVM Value* in the LValue structure is guaranteed to be +/// an LLVM pointer type. +/// +/// If this returns a bitfield reference, nothing about the pointee type of the +/// LLVM value is known: For example, it may not be a pointer to an integer. +/// +/// If this returns a normal address, and if the lvalue's C type is fixed size, +/// this method guarantees that the returned pointer type will point to an LLVM +/// type of the same size of the lvalue's type. If the lvalue has a variable +/// length type, this is not possible. +/// +LValue CodeGenFunction::EmitLValue(const Expr *E) { + switch (E->getStmtClass()) { + default: return EmitUnsupportedLValue(E, "l-value expression"); + + case Expr::ObjCSelectorExprClass: + return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E)); + case Expr::ObjCIsaExprClass: + return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E)); + case Expr::BinaryOperatorClass: + return EmitBinaryOperatorLValue(cast<BinaryOperator>(E)); + case Expr::CompoundAssignOperatorClass: + if (!E->getType()->isAnyComplexType()) + return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E)); + return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E)); + case Expr::CallExprClass: + case Expr::CXXMemberCallExprClass: + case Expr::CXXOperatorCallExprClass: + return EmitCallExprLValue(cast<CallExpr>(E)); + case Expr::VAArgExprClass: + return EmitVAArgExprLValue(cast<VAArgExpr>(E)); + case Expr::DeclRefExprClass: + return EmitDeclRefLValue(cast<DeclRefExpr>(E)); + case Expr::ParenExprClass:return EmitLValue(cast<ParenExpr>(E)->getSubExpr()); + case Expr::GenericSelectionExprClass: + return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr()); + case Expr::PredefinedExprClass: + return EmitPredefinedLValue(cast<PredefinedExpr>(E)); + case Expr::StringLiteralClass: + return EmitStringLiteralLValue(cast<StringLiteral>(E)); + case Expr::ObjCEncodeExprClass: + return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E)); + + case Expr::BlockDeclRefExprClass: + return EmitBlockDeclRefLValue(cast<BlockDeclRefExpr>(E)); + + case Expr::CXXTemporaryObjectExprClass: + case Expr::CXXConstructExprClass: + return EmitCXXConstructLValue(cast<CXXConstructExpr>(E)); + case Expr::CXXBindTemporaryExprClass: + return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E)); + case Expr::ExprWithCleanupsClass: + return EmitExprWithCleanupsLValue(cast<ExprWithCleanups>(E)); + case Expr::CXXScalarValueInitExprClass: + return EmitNullInitializationLValue(cast<CXXScalarValueInitExpr>(E)); + case Expr::CXXDefaultArgExprClass: + return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr()); + case Expr::CXXTypeidExprClass: + return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E)); + + case Expr::ObjCMessageExprClass: + return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E)); + case Expr::ObjCIvarRefExprClass: + return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E)); + case Expr::ObjCPropertyRefExprClass: + return EmitObjCPropertyRefLValue(cast<ObjCPropertyRefExpr>(E)); + case Expr::StmtExprClass: + return EmitStmtExprLValue(cast<StmtExpr>(E)); + case Expr::UnaryOperatorClass: + return EmitUnaryOpLValue(cast<UnaryOperator>(E)); + case Expr::ArraySubscriptExprClass: + return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E)); + case Expr::ExtVectorElementExprClass: + return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E)); + case Expr::MemberExprClass: + return EmitMemberExpr(cast<MemberExpr>(E)); + case Expr::CompoundLiteralExprClass: + return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E)); + case Expr::ConditionalOperatorClass: + return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E)); + case Expr::BinaryConditionalOperatorClass: + return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E)); + case Expr::ChooseExprClass: + return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(getContext())); + case Expr::OpaqueValueExprClass: + return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E)); + case Expr::ImplicitCastExprClass: + case Expr::CStyleCastExprClass: + case Expr::CXXFunctionalCastExprClass: + case Expr::CXXStaticCastExprClass: + case Expr::CXXDynamicCastExprClass: + case Expr::CXXReinterpretCastExprClass: + case Expr::CXXConstCastExprClass: + return EmitCastLValue(cast<CastExpr>(E)); + } +} + +llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile, + unsigned Alignment, QualType Ty, + llvm::MDNode *TBAAInfo) { + llvm::LoadInst *Load = Builder.CreateLoad(Addr, "tmp"); + if (Volatile) + Load->setVolatile(true); + if (Alignment) + Load->setAlignment(Alignment); + if (TBAAInfo) + CGM.DecorateInstruction(Load, TBAAInfo); + + return EmitFromMemory(Load, Ty); +} + +static bool isBooleanUnderlyingType(QualType Ty) { + if (const EnumType *ET = dyn_cast<EnumType>(Ty)) + return ET->getDecl()->getIntegerType()->isBooleanType(); + return false; +} + +llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) { + // Bool has a different representation in memory than in registers. + if (Ty->isBooleanType() || isBooleanUnderlyingType(Ty)) { + // This should really always be an i1, but sometimes it's already + // an i8, and it's awkward to track those cases down. + if (Value->getType()->isIntegerTy(1)) + return Builder.CreateZExt(Value, Builder.getInt8Ty(), "frombool"); + assert(Value->getType()->isIntegerTy(8) && "value rep of bool not i1/i8"); + } + + return Value; +} + +llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) { + // Bool has a different representation in memory than in registers. + if (Ty->isBooleanType() || isBooleanUnderlyingType(Ty)) { + assert(Value->getType()->isIntegerTy(8) && "memory rep of bool not i8"); + return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool"); + } + + return Value; +} + +void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr, + bool Volatile, unsigned Alignment, + QualType Ty, + llvm::MDNode *TBAAInfo) { + Value = EmitToMemory(Value, Ty); + llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile); + if (Alignment) + Store->setAlignment(Alignment); + if (TBAAInfo) + CGM.DecorateInstruction(Store, TBAAInfo); +} + +/// EmitLoadOfLValue - Given an expression that represents a value lvalue, this +/// method emits the address of the lvalue, then loads the result as an rvalue, +/// returning the rvalue. +RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, QualType ExprType) { + if (LV.isObjCWeak()) { + // load of a __weak object. + llvm::Value *AddrWeakObj = LV.getAddress(); + return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this, + AddrWeakObj)); + } + + if (LV.isSimple()) { + llvm::Value *Ptr = LV.getAddress(); + + // Functions are l-values that don't require loading. + if (ExprType->isFunctionType()) + return RValue::get(Ptr); + + // Everything needs a load. + return RValue::get(EmitLoadOfScalar(Ptr, LV.isVolatileQualified(), + LV.getAlignment(), ExprType, + LV.getTBAAInfo())); + + } + + if (LV.isVectorElt()) { + llvm::Value *Vec = Builder.CreateLoad(LV.getVectorAddr(), + LV.isVolatileQualified(), "tmp"); + return RValue::get(Builder.CreateExtractElement(Vec, LV.getVectorIdx(), + "vecext")); + } + + // If this is a reference to a subset of the elements of a vector, either + // shuffle the input or extract/insert them as appropriate. + if (LV.isExtVectorElt()) + return EmitLoadOfExtVectorElementLValue(LV, ExprType); + + if (LV.isBitField()) + return EmitLoadOfBitfieldLValue(LV, ExprType); + + assert(LV.isPropertyRef() && "Unknown LValue type!"); + return EmitLoadOfPropertyRefLValue(LV); +} + +RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV, + QualType ExprType) { + const CGBitFieldInfo &Info = LV.getBitFieldInfo(); + + // Get the output type. + const llvm::Type *ResLTy = ConvertType(ExprType); + unsigned ResSizeInBits = CGM.getTargetData().getTypeSizeInBits(ResLTy); + + // Compute the result as an OR of all of the individual component accesses. + llvm::Value *Res = 0; + for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) { + const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i); + + // Get the field pointer. + llvm::Value *Ptr = LV.getBitFieldBaseAddr(); + + // Only offset by the field index if used, so that incoming values are not + // required to be structures. + if (AI.FieldIndex) + Ptr = Builder.CreateStructGEP(Ptr, AI.FieldIndex, "bf.field"); + + // Offset by the byte offset, if used. + if (!AI.FieldByteOffset.isZero()) { + Ptr = EmitCastToVoidPtr(Ptr); + Ptr = Builder.CreateConstGEP1_32(Ptr, AI.FieldByteOffset.getQuantity(), + "bf.field.offs"); + } + + // Cast to the access type. + const llvm::Type *PTy = llvm::Type::getIntNPtrTy(getLLVMContext(), + AI.AccessWidth, + CGM.getContext().getTargetAddressSpace(ExprType)); + Ptr = Builder.CreateBitCast(Ptr, PTy); + + // Perform the load. + llvm::LoadInst *Load = Builder.CreateLoad(Ptr, LV.isVolatileQualified()); + if (!AI.AccessAlignment.isZero()) + Load->setAlignment(AI.AccessAlignment.getQuantity()); + + // Shift out unused low bits and mask out unused high bits. + llvm::Value *Val = Load; + if (AI.FieldBitStart) + Val = Builder.CreateLShr(Load, AI.FieldBitStart); + Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(AI.AccessWidth, + AI.TargetBitWidth), + "bf.clear"); + + // Extend or truncate to the target size. + if (AI.AccessWidth < ResSizeInBits) + Val = Builder.CreateZExt(Val, ResLTy); + else if (AI.AccessWidth > ResSizeInBits) + Val = Builder.CreateTrunc(Val, ResLTy); + + // Shift into place, and OR into the result. + if (AI.TargetBitOffset) + Val = Builder.CreateShl(Val, AI.TargetBitOffset); + Res = Res ? Builder.CreateOr(Res, Val) : Val; + } + + // If the bit-field is signed, perform the sign-extension. + // + // FIXME: This can easily be folded into the load of the high bits, which + // could also eliminate the mask of high bits in some situations. + if (Info.isSigned()) { + unsigned ExtraBits = ResSizeInBits - Info.getSize(); + if (ExtraBits) + Res = Builder.CreateAShr(Builder.CreateShl(Res, ExtraBits), + ExtraBits, "bf.val.sext"); + } + + return RValue::get(Res); +} + +// If this is a reference to a subset of the elements of a vector, create an +// appropriate shufflevector. +RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV, + QualType ExprType) { + llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddr(), + LV.isVolatileQualified(), "tmp"); + + const llvm::Constant *Elts = LV.getExtVectorElts(); + + // If the result of the expression is a non-vector type, we must be extracting + // a single element. Just codegen as an extractelement. + const VectorType *ExprVT = ExprType->getAs<VectorType>(); + if (!ExprVT) { + unsigned InIdx = getAccessedFieldNo(0, Elts); + llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx); + return RValue::get(Builder.CreateExtractElement(Vec, Elt, "tmp")); + } + + // Always use shuffle vector to try to retain the original program structure + unsigned NumResultElts = ExprVT->getNumElements(); + + llvm::SmallVector<llvm::Constant*, 4> Mask; + for (unsigned i = 0; i != NumResultElts; ++i) { + unsigned InIdx = getAccessedFieldNo(i, Elts); + Mask.push_back(llvm::ConstantInt::get(Int32Ty, InIdx)); + } + + llvm::Value *MaskV = llvm::ConstantVector::get(Mask); + Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()), + MaskV, "tmp"); + return RValue::get(Vec); +} + + + +/// EmitStoreThroughLValue - Store the specified rvalue into the specified +/// lvalue, where both are guaranteed to the have the same type, and that type +/// is 'Ty'. +void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst, + QualType Ty) { + if (!Dst.isSimple()) { + if (Dst.isVectorElt()) { + // Read/modify/write the vector, inserting the new element. + llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddr(), + Dst.isVolatileQualified(), "tmp"); + Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(), + Dst.getVectorIdx(), "vecins"); + Builder.CreateStore(Vec, Dst.getVectorAddr(),Dst.isVolatileQualified()); + return; + } + + // If this is an update of extended vector elements, insert them as + // appropriate. + if (Dst.isExtVectorElt()) + return EmitStoreThroughExtVectorComponentLValue(Src, Dst, Ty); + + if (Dst.isBitField()) + return EmitStoreThroughBitfieldLValue(Src, Dst, Ty); + + assert(Dst.isPropertyRef() && "Unknown LValue type"); + return EmitStoreThroughPropertyRefLValue(Src, Dst); + } + + if (Dst.isObjCWeak() && !Dst.isNonGC()) { + // load of a __weak object. + llvm::Value *LvalueDst = Dst.getAddress(); + llvm::Value *src = Src.getScalarVal(); + CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst); + return; + } + + if (Dst.isObjCStrong() && !Dst.isNonGC()) { + // load of a __strong object. + llvm::Value *LvalueDst = Dst.getAddress(); + llvm::Value *src = Src.getScalarVal(); + if (Dst.isObjCIvar()) { + assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL"); + const llvm::Type *ResultType = ConvertType(getContext().LongTy); + llvm::Value *RHS = EmitScalarExpr(Dst.getBaseIvarExp()); + llvm::Value *dst = RHS; + RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); + llvm::Value *LHS = + Builder.CreatePtrToInt(LvalueDst, ResultType, "sub.ptr.lhs.cast"); + llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset"); + CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst, + BytesBetween); + } else if (Dst.isGlobalObjCRef()) { + CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst, + Dst.isThreadLocalRef()); + } + else + CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst); + return; + } + + assert(Src.isScalar() && "Can't emit an agg store with this method"); + EmitStoreOfScalar(Src.getScalarVal(), Dst.getAddress(), + Dst.isVolatileQualified(), Dst.getAlignment(), Ty, + Dst.getTBAAInfo()); +} + +void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst, + QualType Ty, + llvm::Value **Result) { + const CGBitFieldInfo &Info = Dst.getBitFieldInfo(); + + // Get the output type. + const llvm::Type *ResLTy = ConvertTypeForMem(Ty); + unsigned ResSizeInBits = CGM.getTargetData().getTypeSizeInBits(ResLTy); + + // Get the source value, truncated to the width of the bit-field. + llvm::Value *SrcVal = Src.getScalarVal(); + + if (Ty->isBooleanType()) + SrcVal = Builder.CreateIntCast(SrcVal, ResLTy, /*IsSigned=*/false); + + SrcVal = Builder.CreateAnd(SrcVal, llvm::APInt::getLowBitsSet(ResSizeInBits, + Info.getSize()), + "bf.value"); + + // Return the new value of the bit-field, if requested. + if (Result) { + // Cast back to the proper type for result. + const llvm::Type *SrcTy = Src.getScalarVal()->getType(); + llvm::Value *ReloadVal = Builder.CreateIntCast(SrcVal, SrcTy, false, + "bf.reload.val"); + + // Sign extend if necessary. + if (Info.isSigned()) { + unsigned ExtraBits = ResSizeInBits - Info.getSize(); + if (ExtraBits) + ReloadVal = Builder.CreateAShr(Builder.CreateShl(ReloadVal, ExtraBits), + ExtraBits, "bf.reload.sext"); + } + + *Result = ReloadVal; + } + + // Iterate over the components, writing each piece to memory. + for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) { + const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i); + + // Get the field pointer. + llvm::Value *Ptr = Dst.getBitFieldBaseAddr(); + unsigned addressSpace = + cast<llvm::PointerType>(Ptr->getType())->getAddressSpace(); + + // Only offset by the field index if used, so that incoming values are not + // required to be structures. + if (AI.FieldIndex) + Ptr = Builder.CreateStructGEP(Ptr, AI.FieldIndex, "bf.field"); + + // Offset by the byte offset, if used. + if (!AI.FieldByteOffset.isZero()) { + Ptr = EmitCastToVoidPtr(Ptr); + Ptr = Builder.CreateConstGEP1_32(Ptr, AI.FieldByteOffset.getQuantity(), + "bf.field.offs"); + } + + // Cast to the access type. + const llvm::Type *AccessLTy = + llvm::Type::getIntNTy(getLLVMContext(), AI.AccessWidth); + + const llvm::Type *PTy = AccessLTy->getPointerTo(addressSpace); + Ptr = Builder.CreateBitCast(Ptr, PTy); + + // Extract the piece of the bit-field value to write in this access, limited + // to the values that are part of this access. + llvm::Value *Val = SrcVal; + if (AI.TargetBitOffset) + Val = Builder.CreateLShr(Val, AI.TargetBitOffset); + Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(ResSizeInBits, + AI.TargetBitWidth)); + + // Extend or truncate to the access size. + if (ResSizeInBits < AI.AccessWidth) + Val = Builder.CreateZExt(Val, AccessLTy); + else if (ResSizeInBits > AI.AccessWidth) + Val = Builder.CreateTrunc(Val, AccessLTy); + + // Shift into the position in memory. + if (AI.FieldBitStart) + Val = Builder.CreateShl(Val, AI.FieldBitStart); + + // If necessary, load and OR in bits that are outside of the bit-field. + if (AI.TargetBitWidth != AI.AccessWidth) { + llvm::LoadInst *Load = Builder.CreateLoad(Ptr, Dst.isVolatileQualified()); + if (!AI.AccessAlignment.isZero()) + Load->setAlignment(AI.AccessAlignment.getQuantity()); + + // Compute the mask for zeroing the bits that are part of the bit-field. + llvm::APInt InvMask = + ~llvm::APInt::getBitsSet(AI.AccessWidth, AI.FieldBitStart, + AI.FieldBitStart + AI.TargetBitWidth); + + // Apply the mask and OR in to the value to write. + Val = Builder.CreateOr(Builder.CreateAnd(Load, InvMask), Val); + } + + // Write the value. + llvm::StoreInst *Store = Builder.CreateStore(Val, Ptr, + Dst.isVolatileQualified()); + if (!AI.AccessAlignment.isZero()) + Store->setAlignment(AI.AccessAlignment.getQuantity()); + } +} + +void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src, + LValue Dst, + QualType Ty) { + // This access turns into a read/modify/write of the vector. Load the input + // value now. + llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddr(), + Dst.isVolatileQualified(), "tmp"); + const llvm::Constant *Elts = Dst.getExtVectorElts(); + + llvm::Value *SrcVal = Src.getScalarVal(); + + if (const VectorType *VTy = Ty->getAs<VectorType>()) { + unsigned NumSrcElts = VTy->getNumElements(); + unsigned NumDstElts = + cast<llvm::VectorType>(Vec->getType())->getNumElements(); + if (NumDstElts == NumSrcElts) { + // Use shuffle vector is the src and destination are the same number of + // elements and restore the vector mask since it is on the side it will be + // stored. + llvm::SmallVector<llvm::Constant*, 4> Mask(NumDstElts); + for (unsigned i = 0; i != NumSrcElts; ++i) { + unsigned InIdx = getAccessedFieldNo(i, Elts); + Mask[InIdx] = llvm::ConstantInt::get(Int32Ty, i); + } + + llvm::Value *MaskV = llvm::ConstantVector::get(Mask); + Vec = Builder.CreateShuffleVector(SrcVal, + llvm::UndefValue::get(Vec->getType()), + MaskV, "tmp"); + } else if (NumDstElts > NumSrcElts) { + // Extended the source vector to the same length and then shuffle it + // into the destination. + // FIXME: since we're shuffling with undef, can we just use the indices + // into that? This could be simpler. + llvm::SmallVector<llvm::Constant*, 4> ExtMask; + unsigned i; + for (i = 0; i != NumSrcElts; ++i) + ExtMask.push_back(llvm::ConstantInt::get(Int32Ty, i)); + for (; i != NumDstElts; ++i) + ExtMask.push_back(llvm::UndefValue::get(Int32Ty)); + llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask); + llvm::Value *ExtSrcVal = + Builder.CreateShuffleVector(SrcVal, + llvm::UndefValue::get(SrcVal->getType()), + ExtMaskV, "tmp"); + // build identity + llvm::SmallVector<llvm::Constant*, 4> Mask; + for (unsigned i = 0; i != NumDstElts; ++i) + Mask.push_back(llvm::ConstantInt::get(Int32Ty, i)); + + // modify when what gets shuffled in + for (unsigned i = 0; i != NumSrcElts; ++i) { + unsigned Idx = getAccessedFieldNo(i, Elts); + Mask[Idx] = llvm::ConstantInt::get(Int32Ty, i+NumDstElts); + } + llvm::Value *MaskV = llvm::ConstantVector::get(Mask); + Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV, "tmp"); + } else { + // We should never shorten the vector + assert(0 && "unexpected shorten vector length"); + } + } else { + // If the Src is a scalar (not a vector) it must be updating one element. + unsigned InIdx = getAccessedFieldNo(0, Elts); + llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx); + Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt, "tmp"); + } + + Builder.CreateStore(Vec, Dst.getExtVectorAddr(), Dst.isVolatileQualified()); +} + +// setObjCGCLValueClass - sets class of he lvalue for the purpose of +// generating write-barries API. It is currently a global, ivar, +// or neither. +static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E, + LValue &LV) { + if (Ctx.getLangOptions().getGCMode() == LangOptions::NonGC) + return; + + if (isa<ObjCIvarRefExpr>(E)) { + LV.setObjCIvar(true); + ObjCIvarRefExpr *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr*>(E)); + LV.setBaseIvarExp(Exp->getBase()); + LV.setObjCArray(E->getType()->isArrayType()); + return; + } + + if (const DeclRefExpr *Exp = dyn_cast<DeclRefExpr>(E)) { + if (const VarDecl *VD = dyn_cast<VarDecl>(Exp->getDecl())) { + if (VD->hasGlobalStorage()) { + LV.setGlobalObjCRef(true); + LV.setThreadLocalRef(VD->isThreadSpecified()); + } + } + LV.setObjCArray(E->getType()->isArrayType()); + return; + } + + if (const UnaryOperator *Exp = dyn_cast<UnaryOperator>(E)) { + setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV); + return; + } + + if (const ParenExpr *Exp = dyn_cast<ParenExpr>(E)) { + setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV); + if (LV.isObjCIvar()) { + // If cast is to a structure pointer, follow gcc's behavior and make it + // a non-ivar write-barrier. + QualType ExpTy = E->getType(); + if (ExpTy->isPointerType()) + ExpTy = ExpTy->getAs<PointerType>()->getPointeeType(); + if (ExpTy->isRecordType()) + LV.setObjCIvar(false); + } + return; + } + + if (const GenericSelectionExpr *Exp = dyn_cast<GenericSelectionExpr>(E)) { + setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV); + return; + } + + if (const ImplicitCastExpr *Exp = dyn_cast<ImplicitCastExpr>(E)) { + setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV); + return; + } + + if (const CStyleCastExpr *Exp = dyn_cast<CStyleCastExpr>(E)) { + setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV); + return; + } + + if (const ArraySubscriptExpr *Exp = dyn_cast<ArraySubscriptExpr>(E)) { + setObjCGCLValueClass(Ctx, Exp->getBase(), LV); + if (LV.isObjCIvar() && !LV.isObjCArray()) + // Using array syntax to assigning to what an ivar points to is not + // same as assigning to the ivar itself. {id *Names;} Names[i] = 0; + LV.setObjCIvar(false); + else if (LV.isGlobalObjCRef() && !LV.isObjCArray()) + // Using array syntax to assigning to what global points to is not + // same as assigning to the global itself. {id *G;} G[i] = 0; + LV.setGlobalObjCRef(false); + return; + } + + if (const MemberExpr *Exp = dyn_cast<MemberExpr>(E)) { + setObjCGCLValueClass(Ctx, Exp->getBase(), LV); + // We don't know if member is an 'ivar', but this flag is looked at + // only in the context of LV.isObjCIvar(). + LV.setObjCArray(E->getType()->isArrayType()); + return; + } +} + +static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF, + const Expr *E, const VarDecl *VD) { + assert((VD->hasExternalStorage() || VD->isFileVarDecl()) && + "Var decl must have external storage or be a file var decl!"); + + llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD); + if (VD->getType()->isReferenceType()) + V = CGF.Builder.CreateLoad(V, "tmp"); + unsigned Alignment = CGF.getContext().getDeclAlign(VD).getQuantity(); + LValue LV = CGF.MakeAddrLValue(V, E->getType(), Alignment); + setObjCGCLValueClass(CGF.getContext(), E, LV); + return LV; +} + +static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF, + const Expr *E, const FunctionDecl *FD) { + llvm::Value *V = CGF.CGM.GetAddrOfFunction(FD); + if (!FD->hasPrototype()) { + if (const FunctionProtoType *Proto = + FD->getType()->getAs<FunctionProtoType>()) { + // Ugly case: for a K&R-style definition, the type of the definition + // isn't the same as the type of a use. Correct for this with a + // bitcast. + QualType NoProtoType = + CGF.getContext().getFunctionNoProtoType(Proto->getResultType()); + NoProtoType = CGF.getContext().getPointerType(NoProtoType); + V = CGF.Builder.CreateBitCast(V, CGF.ConvertType(NoProtoType), "tmp"); + } + } + unsigned Alignment = CGF.getContext().getDeclAlign(FD).getQuantity(); + return CGF.MakeAddrLValue(V, E->getType(), Alignment); +} + +LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) { + const NamedDecl *ND = E->getDecl(); + unsigned Alignment = getContext().getDeclAlign(ND).getQuantity(); + + if (ND->hasAttr<WeakRefAttr>()) { + const ValueDecl *VD = cast<ValueDecl>(ND); + llvm::Constant *Aliasee = CGM.GetWeakRefReference(VD); + return MakeAddrLValue(Aliasee, E->getType(), Alignment); + } + + if (const VarDecl *VD = dyn_cast<VarDecl>(ND)) { + + // Check if this is a global variable. + if (VD->hasExternalStorage() || VD->isFileVarDecl()) + return EmitGlobalVarDeclLValue(*this, E, VD); + + bool NonGCable = VD->hasLocalStorage() && + !VD->getType()->isReferenceType() && + !VD->hasAttr<BlocksAttr>(); + + llvm::Value *V = LocalDeclMap[VD]; + if (!V && VD->isStaticLocal()) + V = CGM.getStaticLocalDeclAddress(VD); + assert(V && "DeclRefExpr not entered in LocalDeclMap?"); + + if (VD->hasAttr<BlocksAttr>()) + V = BuildBlockByrefAddress(V, VD); + + if (VD->getType()->isReferenceType()) + V = Builder.CreateLoad(V, "tmp"); + + LValue LV = MakeAddrLValue(V, E->getType(), Alignment); + if (NonGCable) { + LV.getQuals().removeObjCGCAttr(); + LV.setNonGC(true); + } + setObjCGCLValueClass(getContext(), E, LV); + return LV; + } + + if (const FunctionDecl *fn = dyn_cast<FunctionDecl>(ND)) + return EmitFunctionDeclLValue(*this, E, fn); + + assert(false && "Unhandled DeclRefExpr"); + + // an invalid LValue, but the assert will + // ensure that this point is never reached. + return LValue(); +} + +LValue CodeGenFunction::EmitBlockDeclRefLValue(const BlockDeclRefExpr *E) { + unsigned Alignment = + getContext().getDeclAlign(E->getDecl()).getQuantity(); + return MakeAddrLValue(GetAddrOfBlockDecl(E), E->getType(), Alignment); +} + +LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) { + // __extension__ doesn't affect lvalue-ness. + if (E->getOpcode() == UO_Extension) + return EmitLValue(E->getSubExpr()); + + QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType()); + switch (E->getOpcode()) { + default: assert(0 && "Unknown unary operator lvalue!"); + case UO_Deref: { + QualType T = E->getSubExpr()->getType()->getPointeeType(); + assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type"); + + LValue LV = MakeAddrLValue(EmitScalarExpr(E->getSubExpr()), T); + LV.getQuals().setAddressSpace(ExprTy.getAddressSpace()); + + // We should not generate __weak write barrier on indirect reference + // of a pointer to object; as in void foo (__weak id *param); *param = 0; + // But, we continue to generate __strong write barrier on indirect write + // into a pointer to object. + if (getContext().getLangOptions().ObjC1 && + getContext().getLangOptions().getGCMode() != LangOptions::NonGC && + LV.isObjCWeak()) + LV.setNonGC(!E->isOBJCGCCandidate(getContext())); + return LV; + } + case UO_Real: + case UO_Imag: { + LValue LV = EmitLValue(E->getSubExpr()); + assert(LV.isSimple() && "real/imag on non-ordinary l-value"); + llvm::Value *Addr = LV.getAddress(); + + // real and imag are valid on scalars. This is a faster way of + // testing that. + if (!cast<llvm::PointerType>(Addr->getType()) + ->getElementType()->isStructTy()) { + assert(E->getSubExpr()->getType()->isArithmeticType()); + return LV; + } + + assert(E->getSubExpr()->getType()->isAnyComplexType()); + + unsigned Idx = E->getOpcode() == UO_Imag; + return MakeAddrLValue(Builder.CreateStructGEP(LV.getAddress(), + Idx, "idx"), + ExprTy); + } + case UO_PreInc: + case UO_PreDec: { + LValue LV = EmitLValue(E->getSubExpr()); + bool isInc = E->getOpcode() == UO_PreInc; + + if (E->getType()->isAnyComplexType()) + EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/); + else + EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/); + return LV; + } + } +} + +LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) { + return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E), + E->getType()); +} + +LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) { + return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E), + E->getType()); +} + + +LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) { + switch (E->getIdentType()) { + default: + return EmitUnsupportedLValue(E, "predefined expression"); + + case PredefinedExpr::Func: + case PredefinedExpr::Function: + case PredefinedExpr::PrettyFunction: { + unsigned Type = E->getIdentType(); + std::string GlobalVarName; + + switch (Type) { + default: assert(0 && "Invalid type"); + case PredefinedExpr::Func: + GlobalVarName = "__func__."; + break; + case PredefinedExpr::Function: + GlobalVarName = "__FUNCTION__."; + break; + case PredefinedExpr::PrettyFunction: + GlobalVarName = "__PRETTY_FUNCTION__."; + break; + } + + llvm::StringRef FnName = CurFn->getName(); + if (FnName.startswith("\01")) + FnName = FnName.substr(1); + GlobalVarName += FnName; + + const Decl *CurDecl = CurCodeDecl; + if (CurDecl == 0) + CurDecl = getContext().getTranslationUnitDecl(); + + std::string FunctionName = + (isa<BlockDecl>(CurDecl) + ? FnName.str() + : PredefinedExpr::ComputeName((PredefinedExpr::IdentType)Type, CurDecl)); + + llvm::Constant *C = + CGM.GetAddrOfConstantCString(FunctionName, GlobalVarName.c_str()); + return MakeAddrLValue(C, E->getType()); + } + } +} + +llvm::BasicBlock *CodeGenFunction::getTrapBB() { + const CodeGenOptions &GCO = CGM.getCodeGenOpts(); + + // If we are not optimzing, don't collapse all calls to trap in the function + // to the same call, that way, in the debugger they can see which operation + // did in fact fail. If we are optimizing, we collapse all calls to trap down + // to just one per function to save on codesize. + if (GCO.OptimizationLevel && TrapBB) + return TrapBB; + + llvm::BasicBlock *Cont = 0; + if (HaveInsertPoint()) { + Cont = createBasicBlock("cont"); + EmitBranch(Cont); + } + TrapBB = createBasicBlock("trap"); + EmitBlock(TrapBB); + + llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::trap, 0, 0); + llvm::CallInst *TrapCall = Builder.CreateCall(F); + TrapCall->setDoesNotReturn(); + TrapCall->setDoesNotThrow(); + Builder.CreateUnreachable(); + + if (Cont) + EmitBlock(Cont); + return TrapBB; +} + +/// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an +/// array to pointer, return the array subexpression. +static const Expr *isSimpleArrayDecayOperand(const Expr *E) { + // If this isn't just an array->pointer decay, bail out. + const CastExpr *CE = dyn_cast<CastExpr>(E); + if (CE == 0 || CE->getCastKind() != CK_ArrayToPointerDecay) + return 0; + + // If this is a decay from variable width array, bail out. + const Expr *SubExpr = CE->getSubExpr(); + if (SubExpr->getType()->isVariableArrayType()) + return 0; + + return SubExpr; +} + +LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E) { + // The index must always be an integer, which is not an aggregate. Emit it. + llvm::Value *Idx = EmitScalarExpr(E->getIdx()); + QualType IdxTy = E->getIdx()->getType(); + bool IdxSigned = IdxTy->isSignedIntegerType(); + + // If the base is a vector type, then we are forming a vector element lvalue + // with this subscript. + if (E->getBase()->getType()->isVectorType()) { + // Emit the vector as an lvalue to get its address. + LValue LHS = EmitLValue(E->getBase()); + assert(LHS.isSimple() && "Can only subscript lvalue vectors here!"); + Idx = Builder.CreateIntCast(Idx, Int32Ty, IdxSigned, "vidx"); + return LValue::MakeVectorElt(LHS.getAddress(), Idx, + E->getBase()->getType().getCVRQualifiers()); + } + + // Extend or truncate the index type to 32 or 64-bits. + if (Idx->getType() != IntPtrTy) + Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom"); + + // FIXME: As llvm implements the object size checking, this can come out. + if (CatchUndefined) { + if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E->getBase())){ + if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr())) { + if (ICE->getCastKind() == CK_ArrayToPointerDecay) { + if (const ConstantArrayType *CAT + = getContext().getAsConstantArrayType(DRE->getType())) { + llvm::APInt Size = CAT->getSize(); + llvm::BasicBlock *Cont = createBasicBlock("cont"); + Builder.CreateCondBr(Builder.CreateICmpULE(Idx, + llvm::ConstantInt::get(Idx->getType(), Size)), + Cont, getTrapBB()); + EmitBlock(Cont); + } + } + } + } + } + + // We know that the pointer points to a type of the correct size, unless the + // size is a VLA or Objective-C interface. + llvm::Value *Address = 0; + unsigned ArrayAlignment = 0; + if (const VariableArrayType *VAT = + getContext().getAsVariableArrayType(E->getType())) { + llvm::Value *VLASize = GetVLASize(VAT); + + Idx = Builder.CreateMul(Idx, VLASize); + + // The base must be a pointer, which is not an aggregate. Emit it. + llvm::Value *Base = EmitScalarExpr(E->getBase()); + + Address = EmitCastToVoidPtr(Base); + if (getContext().getLangOptions().isSignedOverflowDefined()) + Address = Builder.CreateGEP(Address, Idx, "arrayidx"); + else + Address = Builder.CreateInBoundsGEP(Address, Idx, "arrayidx"); + Address = Builder.CreateBitCast(Address, Base->getType()); + } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){ + // Indexing over an interface, as in "NSString *P; P[4];" + llvm::Value *InterfaceSize = + llvm::ConstantInt::get(Idx->getType(), + getContext().getTypeSizeInChars(OIT).getQuantity()); + + Idx = Builder.CreateMul(Idx, InterfaceSize); + + // The base must be a pointer, which is not an aggregate. Emit it. + llvm::Value *Base = EmitScalarExpr(E->getBase()); + Address = EmitCastToVoidPtr(Base); + Address = Builder.CreateGEP(Address, Idx, "arrayidx"); + Address = Builder.CreateBitCast(Address, Base->getType()); + } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) { + // If this is A[i] where A is an array, the frontend will have decayed the + // base to be a ArrayToPointerDecay implicit cast. While correct, it is + // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a + // "gep x, i" here. Emit one "gep A, 0, i". + assert(Array->getType()->isArrayType() && + "Array to pointer decay must have array source type!"); + LValue ArrayLV = EmitLValue(Array); + llvm::Value *ArrayPtr = ArrayLV.getAddress(); + llvm::Value *Zero = llvm::ConstantInt::get(Int32Ty, 0); + llvm::Value *Args[] = { Zero, Idx }; + + // Propagate the alignment from the array itself to the result. + ArrayAlignment = ArrayLV.getAlignment(); + + if (getContext().getLangOptions().isSignedOverflowDefined()) + Address = Builder.CreateGEP(ArrayPtr, Args, Args+2, "arrayidx"); + else + Address = Builder.CreateInBoundsGEP(ArrayPtr, Args, Args+2, "arrayidx"); + } else { + // The base must be a pointer, which is not an aggregate. Emit it. + llvm::Value *Base = EmitScalarExpr(E->getBase()); + if (getContext().getLangOptions().isSignedOverflowDefined()) + Address = Builder.CreateGEP(Base, Idx, "arrayidx"); + else + Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx"); + } + + QualType T = E->getBase()->getType()->getPointeeType(); + assert(!T.isNull() && + "CodeGenFunction::EmitArraySubscriptExpr(): Illegal base type"); + + // Limit the alignment to that of the result type. + if (ArrayAlignment) { + unsigned Align = getContext().getTypeAlignInChars(T).getQuantity(); + ArrayAlignment = std::min(Align, ArrayAlignment); + } + + LValue LV = MakeAddrLValue(Address, T, ArrayAlignment); + LV.getQuals().setAddressSpace(E->getBase()->getType().getAddressSpace()); + + if (getContext().getLangOptions().ObjC1 && + getContext().getLangOptions().getGCMode() != LangOptions::NonGC) { + LV.setNonGC(!E->isOBJCGCCandidate(getContext())); + setObjCGCLValueClass(getContext(), E, LV); + } + return LV; +} + +static +llvm::Constant *GenerateConstantVector(llvm::LLVMContext &VMContext, + llvm::SmallVector<unsigned, 4> &Elts) { + llvm::SmallVector<llvm::Constant*, 4> CElts; + + const llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext); + for (unsigned i = 0, e = Elts.size(); i != e; ++i) + CElts.push_back(llvm::ConstantInt::get(Int32Ty, Elts[i])); + + return llvm::ConstantVector::get(CElts); +} + +LValue CodeGenFunction:: +EmitExtVectorElementExpr(const ExtVectorElementExpr *E) { + // Emit the base vector as an l-value. + LValue Base; + + // ExtVectorElementExpr's base can either be a vector or pointer to vector. + if (E->isArrow()) { + // If it is a pointer to a vector, emit the address and form an lvalue with + // it. + llvm::Value *Ptr = EmitScalarExpr(E->getBase()); + const PointerType *PT = E->getBase()->getType()->getAs<PointerType>(); + Base = MakeAddrLValue(Ptr, PT->getPointeeType()); + Base.getQuals().removeObjCGCAttr(); + } else if (E->getBase()->isGLValue()) { + // Otherwise, if the base is an lvalue ( as in the case of foo.x.x), + // emit the base as an lvalue. + assert(E->getBase()->getType()->isVectorType()); + Base = EmitLValue(E->getBase()); + } else { + // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such. + assert(E->getBase()->getType()->getAs<VectorType>() && + "Result must be a vector"); + llvm::Value *Vec = EmitScalarExpr(E->getBase()); + + // Store the vector to memory (because LValue wants an address). + llvm::Value *VecMem = CreateMemTemp(E->getBase()->getType()); + Builder.CreateStore(Vec, VecMem); + Base = MakeAddrLValue(VecMem, E->getBase()->getType()); + } + + // Encode the element access list into a vector of unsigned indices. + llvm::SmallVector<unsigned, 4> Indices; + E->getEncodedElementAccess(Indices); + + if (Base.isSimple()) { + llvm::Constant *CV = GenerateConstantVector(getLLVMContext(), Indices); + return LValue::MakeExtVectorElt(Base.getAddress(), CV, + Base.getVRQualifiers()); + } + assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!"); + + llvm::Constant *BaseElts = Base.getExtVectorElts(); + llvm::SmallVector<llvm::Constant *, 4> CElts; + + for (unsigned i = 0, e = Indices.size(); i != e; ++i) { + if (isa<llvm::ConstantAggregateZero>(BaseElts)) + CElts.push_back(llvm::ConstantInt::get(Int32Ty, 0)); + else + CElts.push_back(cast<llvm::Constant>(BaseElts->getOperand(Indices[i]))); + } + llvm::Constant *CV = llvm::ConstantVector::get(CElts); + return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV, + Base.getVRQualifiers()); +} + +LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) { + bool isNonGC = false; + Expr *BaseExpr = E->getBase(); + llvm::Value *BaseValue = NULL; + Qualifiers BaseQuals; + + // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar. + if (E->isArrow()) { + BaseValue = EmitScalarExpr(BaseExpr); + const PointerType *PTy = + BaseExpr->getType()->getAs<PointerType>(); + BaseQuals = PTy->getPointeeType().getQualifiers(); + } else { + LValue BaseLV = EmitLValue(BaseExpr); + if (BaseLV.isNonGC()) + isNonGC = true; + // FIXME: this isn't right for bitfields. + BaseValue = BaseLV.getAddress(); + QualType BaseTy = BaseExpr->getType(); + BaseQuals = BaseTy.getQualifiers(); + } + + NamedDecl *ND = E->getMemberDecl(); + if (FieldDecl *Field = dyn_cast<FieldDecl>(ND)) { + LValue LV = EmitLValueForField(BaseValue, Field, + BaseQuals.getCVRQualifiers()); + LV.setNonGC(isNonGC); + setObjCGCLValueClass(getContext(), E, LV); + return LV; + } + + if (VarDecl *VD = dyn_cast<VarDecl>(ND)) + return EmitGlobalVarDeclLValue(*this, E, VD); + + if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) + return EmitFunctionDeclLValue(*this, E, FD); + + assert(false && "Unhandled member declaration!"); + return LValue(); +} + +LValue CodeGenFunction::EmitLValueForBitfield(llvm::Value *BaseValue, + const FieldDecl *Field, + unsigned CVRQualifiers) { + const CGRecordLayout &RL = + CGM.getTypes().getCGRecordLayout(Field->getParent()); + const CGBitFieldInfo &Info = RL.getBitFieldInfo(Field); + return LValue::MakeBitfield(BaseValue, Info, + Field->getType().getCVRQualifiers()|CVRQualifiers); +} + +/// EmitLValueForAnonRecordField - Given that the field is a member of +/// an anonymous struct or union buried inside a record, and given +/// that the base value is a pointer to the enclosing record, derive +/// an lvalue for the ultimate field. +LValue CodeGenFunction::EmitLValueForAnonRecordField(llvm::Value *BaseValue, + const IndirectFieldDecl *Field, + unsigned CVRQualifiers) { + IndirectFieldDecl::chain_iterator I = Field->chain_begin(), + IEnd = Field->chain_end(); + while (true) { + LValue LV = EmitLValueForField(BaseValue, cast<FieldDecl>(*I), CVRQualifiers); + if (++I == IEnd) return LV; + + assert(LV.isSimple()); + BaseValue = LV.getAddress(); + CVRQualifiers |= LV.getVRQualifiers(); + } +} + +LValue CodeGenFunction::EmitLValueForField(llvm::Value *baseAddr, + const FieldDecl *field, + unsigned cvr) { + if (field->isBitField()) + return EmitLValueForBitfield(baseAddr, field, cvr); + + const RecordDecl *rec = field->getParent(); + QualType type = field->getType(); + + bool mayAlias = rec->hasAttr<MayAliasAttr>(); + + llvm::Value *addr; + if (rec->isUnion()) { + // For unions, we just cast to the appropriate type. + assert(!type->isReferenceType() && "union has reference member"); + + const llvm::Type *llvmType = CGM.getTypes().ConvertTypeForMem(type); + unsigned AS = + cast<llvm::PointerType>(baseAddr->getType())->getAddressSpace(); + addr = Builder.CreateBitCast(baseAddr, llvmType->getPointerTo(AS), + field->getName()); + } else { + // For structs, we GEP to the field that the record layout suggests. + unsigned idx = CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field); + addr = Builder.CreateStructGEP(baseAddr, idx, field->getName()); + + // If this is a reference field, load the reference right now. + if (const ReferenceType *refType = type->getAs<ReferenceType>()) { + llvm::LoadInst *load = Builder.CreateLoad(addr, "ref"); + if (cvr & Qualifiers::Volatile) load->setVolatile(true); + + if (CGM.shouldUseTBAA()) { + llvm::MDNode *tbaa; + if (mayAlias) + tbaa = CGM.getTBAAInfo(getContext().CharTy); + else + tbaa = CGM.getTBAAInfo(type); + CGM.DecorateInstruction(load, tbaa); + } + + addr = load; + mayAlias = false; + type = refType->getPointeeType(); + cvr = 0; // qualifiers don't recursively apply to referencee + } + } + + unsigned alignment = getContext().getDeclAlign(field).getQuantity(); + LValue LV = MakeAddrLValue(addr, type, alignment); + LV.getQuals().addCVRQualifiers(cvr); + + // __weak attribute on a field is ignored. + if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak) + LV.getQuals().removeObjCGCAttr(); + + // Fields of may_alias structs act like 'char' for TBAA purposes. + // FIXME: this should get propagated down through anonymous structs + // and unions. + if (mayAlias && LV.getTBAAInfo()) + LV.setTBAAInfo(CGM.getTBAAInfo(getContext().CharTy)); + + return LV; +} + +LValue +CodeGenFunction::EmitLValueForFieldInitialization(llvm::Value *BaseValue, + const FieldDecl *Field, + unsigned CVRQualifiers) { + QualType FieldType = Field->getType(); + + if (!FieldType->isReferenceType()) + return EmitLValueForField(BaseValue, Field, CVRQualifiers); + + const CGRecordLayout &RL = + CGM.getTypes().getCGRecordLayout(Field->getParent()); + unsigned idx = RL.getLLVMFieldNo(Field); + llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx, "tmp"); + + assert(!FieldType.getObjCGCAttr() && "fields cannot have GC attrs"); + + unsigned Alignment = getContext().getDeclAlign(Field).getQuantity(); + return MakeAddrLValue(V, FieldType, Alignment); +} + +LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){ + llvm::Value *DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral"); + const Expr *InitExpr = E->getInitializer(); + LValue Result = MakeAddrLValue(DeclPtr, E->getType()); + + EmitAnyExprToMem(InitExpr, DeclPtr, /*Volatile*/ false, /*Init*/ true); + + return Result; +} + +LValue CodeGenFunction:: +EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) { + if (!expr->isGLValue()) { + // ?: here should be an aggregate. + assert((hasAggregateLLVMType(expr->getType()) && + !expr->getType()->isAnyComplexType()) && + "Unexpected conditional operator!"); + return EmitAggExprToLValue(expr); + } + + const Expr *condExpr = expr->getCond(); + bool CondExprBool; + if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) { + const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr(); + if (!CondExprBool) std::swap(live, dead); + + if (!ContainsLabel(dead)) + return EmitLValue(live); + } + + OpaqueValueMapping binding(*this, expr); + + llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true"); + llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false"); + llvm::BasicBlock *contBlock = createBasicBlock("cond.end"); + + ConditionalEvaluation eval(*this); + EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock); + + // Any temporaries created here are conditional. + EmitBlock(lhsBlock); + eval.begin(*this); + LValue lhs = EmitLValue(expr->getTrueExpr()); + eval.end(*this); + + if (!lhs.isSimple()) + return EmitUnsupportedLValue(expr, "conditional operator"); + + lhsBlock = Builder.GetInsertBlock(); + Builder.CreateBr(contBlock); + + // Any temporaries created here are conditional. + EmitBlock(rhsBlock); + eval.begin(*this); + LValue rhs = EmitLValue(expr->getFalseExpr()); + eval.end(*this); + if (!rhs.isSimple()) + return EmitUnsupportedLValue(expr, "conditional operator"); + rhsBlock = Builder.GetInsertBlock(); + + EmitBlock(contBlock); + + llvm::PHINode *phi = Builder.CreatePHI(lhs.getAddress()->getType(), 2, + "cond-lvalue"); + phi->addIncoming(lhs.getAddress(), lhsBlock); + phi->addIncoming(rhs.getAddress(), rhsBlock); + return MakeAddrLValue(phi, expr->getType()); +} + +/// EmitCastLValue - Casts are never lvalues unless that cast is a dynamic_cast. +/// If the cast is a dynamic_cast, we can have the usual lvalue result, +/// otherwise if a cast is needed by the code generator in an lvalue context, +/// then it must mean that we need the address of an aggregate in order to +/// access one of its fields. This can happen for all the reasons that casts +/// are permitted with aggregate result, including noop aggregate casts, and +/// cast from scalar to union. +LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) { + switch (E->getCastKind()) { + case CK_ToVoid: + return EmitUnsupportedLValue(E, "unexpected cast lvalue"); + + case CK_Dependent: + llvm_unreachable("dependent cast kind in IR gen!"); + + case CK_GetObjCProperty: { + LValue LV = EmitLValue(E->getSubExpr()); + assert(LV.isPropertyRef()); + RValue RV = EmitLoadOfPropertyRefLValue(LV); + + // Property is an aggregate r-value. + if (RV.isAggregate()) { + return MakeAddrLValue(RV.getAggregateAddr(), E->getType()); + } + + // Implicit property returns an l-value. + assert(RV.isScalar()); + return MakeAddrLValue(RV.getScalarVal(), E->getSubExpr()->getType()); + } + + case CK_NoOp: + case CK_LValueToRValue: + if (!E->getSubExpr()->Classify(getContext()).isPRValue() + || E->getType()->isRecordType()) + return EmitLValue(E->getSubExpr()); + // Fall through to synthesize a temporary. + + case CK_BitCast: + case CK_ArrayToPointerDecay: + case CK_FunctionToPointerDecay: + case CK_NullToMemberPointer: + case CK_NullToPointer: + case CK_IntegralToPointer: + case CK_PointerToIntegral: + case CK_PointerToBoolean: + case CK_VectorSplat: + case CK_IntegralCast: + case CK_IntegralToBoolean: + case CK_IntegralToFloating: + case CK_FloatingToIntegral: + case CK_FloatingToBoolean: + case CK_FloatingCast: + case CK_FloatingRealToComplex: + case CK_FloatingComplexToReal: + case CK_FloatingComplexToBoolean: + case CK_FloatingComplexCast: + case CK_FloatingComplexToIntegralComplex: + case CK_IntegralRealToComplex: + case CK_IntegralComplexToReal: + case CK_IntegralComplexToBoolean: + case CK_IntegralComplexCast: + case CK_IntegralComplexToFloatingComplex: + case CK_DerivedToBaseMemberPointer: + case CK_BaseToDerivedMemberPointer: + case CK_MemberPointerToBoolean: + case CK_AnyPointerToBlockPointerCast: { + // These casts only produce lvalues when we're binding a reference to a + // temporary realized from a (converted) pure rvalue. Emit the expression + // as a value, copy it into a temporary, and return an lvalue referring to + // that temporary. + llvm::Value *V = CreateMemTemp(E->getType(), "ref.temp"); + EmitAnyExprToMem(E, V, false, false); + return MakeAddrLValue(V, E->getType()); + } + + case CK_Dynamic: { + LValue LV = EmitLValue(E->getSubExpr()); + llvm::Value *V = LV.getAddress(); + const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(E); + return MakeAddrLValue(EmitDynamicCast(V, DCE), E->getType()); + } + + case CK_ConstructorConversion: + case CK_UserDefinedConversion: + case CK_AnyPointerToObjCPointerCast: + return EmitLValue(E->getSubExpr()); + + case CK_UncheckedDerivedToBase: + case CK_DerivedToBase: { + const RecordType *DerivedClassTy = + E->getSubExpr()->getType()->getAs<RecordType>(); + CXXRecordDecl *DerivedClassDecl = + cast<CXXRecordDecl>(DerivedClassTy->getDecl()); + + LValue LV = EmitLValue(E->getSubExpr()); + llvm::Value *This = LV.getAddress(); + + // Perform the derived-to-base conversion + llvm::Value *Base = + GetAddressOfBaseClass(This, DerivedClassDecl, + E->path_begin(), E->path_end(), + /*NullCheckValue=*/false); + + return MakeAddrLValue(Base, E->getType()); + } + case CK_ToUnion: + return EmitAggExprToLValue(E); + case CK_BaseToDerived: { + const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>(); + CXXRecordDecl *DerivedClassDecl = + cast<CXXRecordDecl>(DerivedClassTy->getDecl()); + + LValue LV = EmitLValue(E->getSubExpr()); + + // Perform the base-to-derived conversion + llvm::Value *Derived = + GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl, + E->path_begin(), E->path_end(), + /*NullCheckValue=*/false); + + return MakeAddrLValue(Derived, E->getType()); + } + case CK_LValueBitCast: { + // This must be a reinterpret_cast (or c-style equivalent). + const ExplicitCastExpr *CE = cast<ExplicitCastExpr>(E); + + LValue LV = EmitLValue(E->getSubExpr()); + llvm::Value *V = Builder.CreateBitCast(LV.getAddress(), + ConvertType(CE->getTypeAsWritten())); + return MakeAddrLValue(V, E->getType()); + } + case CK_ObjCObjectLValueCast: { + LValue LV = EmitLValue(E->getSubExpr()); + QualType ToType = getContext().getLValueReferenceType(E->getType()); + llvm::Value *V = Builder.CreateBitCast(LV.getAddress(), + ConvertType(ToType)); + return MakeAddrLValue(V, E->getType()); + } + } + + llvm_unreachable("Unhandled lvalue cast kind?"); +} + +LValue CodeGenFunction::EmitNullInitializationLValue( + const CXXScalarValueInitExpr *E) { + QualType Ty = E->getType(); + LValue LV = MakeAddrLValue(CreateMemTemp(Ty), Ty); + EmitNullInitialization(LV.getAddress(), Ty); + return LV; +} + +LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) { + assert(e->isGLValue() || e->getType()->isRecordType()); + return getOpaqueLValueMapping(e); +} + +//===--------------------------------------------------------------------===// +// Expression Emission +//===--------------------------------------------------------------------===// + + +RValue CodeGenFunction::EmitCallExpr(const CallExpr *E, + ReturnValueSlot ReturnValue) { + if (CGDebugInfo *DI = getDebugInfo()) { + DI->setLocation(E->getLocStart()); + DI->UpdateLineDirectiveRegion(Builder); + DI->EmitStopPoint(Builder); + } + + // Builtins never have block type. + if (E->getCallee()->getType()->isBlockPointerType()) + return EmitBlockCallExpr(E, ReturnValue); + + if (const CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(E)) + return EmitCXXMemberCallExpr(CE, ReturnValue); + + const Decl *TargetDecl = 0; + if (const ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E->getCallee())) { + if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CE->getSubExpr())) { + TargetDecl = DRE->getDecl(); + if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(TargetDecl)) + if (unsigned builtinID = FD->getBuiltinID()) + return EmitBuiltinExpr(FD, builtinID, E); + } + } + + if (const CXXOperatorCallExpr *CE = dyn_cast<CXXOperatorCallExpr>(E)) + if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(TargetDecl)) + return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue); + + if (isa<CXXPseudoDestructorExpr>(E->getCallee()->IgnoreParens())) { + // C++ [expr.pseudo]p1: + // The result shall only be used as the operand for the function call + // operator (), and the result of such a call has type void. The only + // effect is the evaluation of the postfix-expression before the dot or + // arrow. + EmitScalarExpr(E->getCallee()); + return RValue::get(0); + } + + llvm::Value *Callee = EmitScalarExpr(E->getCallee()); + return EmitCall(E->getCallee()->getType(), Callee, ReturnValue, + E->arg_begin(), E->arg_end(), TargetDecl); +} + +LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) { + // Comma expressions just emit their LHS then their RHS as an l-value. + if (E->getOpcode() == BO_Comma) { + EmitIgnoredExpr(E->getLHS()); + EnsureInsertPoint(); + return EmitLValue(E->getRHS()); + } + + if (E->getOpcode() == BO_PtrMemD || + E->getOpcode() == BO_PtrMemI) + return EmitPointerToDataMemberBinaryExpr(E); + + assert(E->getOpcode() == BO_Assign && "unexpected binary l-value"); + + if (!hasAggregateLLVMType(E->getType())) { + // __block variables need the RHS evaluated first. + RValue RV = EmitAnyExpr(E->getRHS()); + LValue LV = EmitLValue(E->getLHS()); + EmitStoreThroughLValue(RV, LV, E->getType()); + return LV; + } + + if (E->getType()->isAnyComplexType()) + return EmitComplexAssignmentLValue(E); + + return EmitAggExprToLValue(E); +} + +LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) { + RValue RV = EmitCallExpr(E); + + if (!RV.isScalar()) + return MakeAddrLValue(RV.getAggregateAddr(), E->getType()); + + assert(E->getCallReturnType()->isReferenceType() && + "Can't have a scalar return unless the return type is a " + "reference type!"); + + return MakeAddrLValue(RV.getScalarVal(), E->getType()); +} + +LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) { + // FIXME: This shouldn't require another copy. + return EmitAggExprToLValue(E); +} + +LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) { + assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor() + && "binding l-value to type which needs a temporary"); + AggValueSlot Slot = CreateAggTemp(E->getType(), "tmp"); + EmitCXXConstructExpr(E, Slot); + return MakeAddrLValue(Slot.getAddr(), E->getType()); +} + +LValue +CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) { + return MakeAddrLValue(EmitCXXTypeidExpr(E), E->getType()); +} + +LValue +CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) { + AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue"); + Slot.setLifetimeExternallyManaged(); + EmitAggExpr(E->getSubExpr(), Slot); + EmitCXXTemporary(E->getTemporary(), Slot.getAddr()); + return MakeAddrLValue(Slot.getAddr(), E->getType()); +} + +LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) { + RValue RV = EmitObjCMessageExpr(E); + + if (!RV.isScalar()) + return MakeAddrLValue(RV.getAggregateAddr(), E->getType()); + + assert(E->getMethodDecl()->getResultType()->isReferenceType() && + "Can't have a scalar return unless the return type is a " + "reference type!"); + + return MakeAddrLValue(RV.getScalarVal(), E->getType()); +} + +LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) { + llvm::Value *V = + CGM.getObjCRuntime().GetSelector(Builder, E->getSelector(), true); + return MakeAddrLValue(V, E->getType()); +} + +llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface, + const ObjCIvarDecl *Ivar) { + return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar); +} + +LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy, + llvm::Value *BaseValue, + const ObjCIvarDecl *Ivar, + unsigned CVRQualifiers) { + return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue, + Ivar, CVRQualifiers); +} + +LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) { + // FIXME: A lot of the code below could be shared with EmitMemberExpr. + llvm::Value *BaseValue = 0; + const Expr *BaseExpr = E->getBase(); + Qualifiers BaseQuals; + QualType ObjectTy; + if (E->isArrow()) { + BaseValue = EmitScalarExpr(BaseExpr); + ObjectTy = BaseExpr->getType()->getPointeeType(); + BaseQuals = ObjectTy.getQualifiers(); + } else { + LValue BaseLV = EmitLValue(BaseExpr); + // FIXME: this isn't right for bitfields. + BaseValue = BaseLV.getAddress(); + ObjectTy = BaseExpr->getType(); + BaseQuals = ObjectTy.getQualifiers(); + } + + LValue LV = + EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(), + BaseQuals.getCVRQualifiers()); + setObjCGCLValueClass(getContext(), E, LV); + return LV; +} + +LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) { + // Can only get l-value for message expression returning aggregate type + RValue RV = EmitAnyExprToTemp(E); + return MakeAddrLValue(RV.getAggregateAddr(), E->getType()); +} + +RValue CodeGenFunction::EmitCall(QualType CalleeType, llvm::Value *Callee, + ReturnValueSlot ReturnValue, + CallExpr::const_arg_iterator ArgBeg, + CallExpr::const_arg_iterator ArgEnd, + const Decl *TargetDecl) { + // Get the actual function type. The callee type will always be a pointer to + // function type or a block pointer type. + assert(CalleeType->isFunctionPointerType() && + "Call must have function pointer type!"); + + CalleeType = getContext().getCanonicalType(CalleeType); + + const FunctionType *FnType + = cast<FunctionType>(cast<PointerType>(CalleeType)->getPointeeType()); + + CallArgList Args; + EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), ArgBeg, ArgEnd); + + return EmitCall(CGM.getTypes().getFunctionInfo(Args, FnType), + Callee, ReturnValue, Args, TargetDecl); +} + +LValue CodeGenFunction:: +EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) { + llvm::Value *BaseV; + if (E->getOpcode() == BO_PtrMemI) + BaseV = EmitScalarExpr(E->getLHS()); + else + BaseV = EmitLValue(E->getLHS()).getAddress(); + + llvm::Value *OffsetV = EmitScalarExpr(E->getRHS()); + + const MemberPointerType *MPT + = E->getRHS()->getType()->getAs<MemberPointerType>(); + + llvm::Value *AddV = + CGM.getCXXABI().EmitMemberDataPointerAddress(*this, BaseV, OffsetV, MPT); + + return MakeAddrLValue(AddV, MPT->getPointeeType()); +} |
