//===--- 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 "CGObjCRuntime.h" #include "clang/AST/ASTContext.h" #include "clang/AST/DeclObjC.h" #include "llvm/Target/TargetData.h" using namespace clang; using namespace CodeGen; //===--------------------------------------------------------------------===// // Miscellaneous Helper Methods //===--------------------------------------------------------------------===// /// 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); } /// 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) { QualType BoolTy = getContext().BoolTy; if (!E->getType()->isAnyComplexType()) return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy); return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(),BoolTy); } /// 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, the aggloc/agglocvolatile arguments indicate where the /// result should be returned. RValue CodeGenFunction::EmitAnyExpr(const Expr *E, llvm::Value *AggLoc, bool IsAggLocVolatile, bool IgnoreResult, bool IsInitializer) { if (!hasAggregateLLVMType(E->getType())) return RValue::get(EmitScalarExpr(E, IgnoreResult)); else if (E->getType()->isAnyComplexType()) return RValue::getComplex(EmitComplexExpr(E, false, false, IgnoreResult, IgnoreResult)); EmitAggExpr(E, AggLoc, IsAggLocVolatile, IgnoreResult, IsInitializer); return RValue::getAggregate(AggLoc, IsAggLocVolatile); } /// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will /// always be accessible even if no aggregate location is provided. RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E, bool IsAggLocVolatile, bool IsInitializer) { llvm::Value *AggLoc = 0; if (hasAggregateLLVMType(E->getType()) && !E->getType()->isAnyComplexType()) AggLoc = CreateTempAlloca(ConvertType(E->getType()), "agg.tmp"); return EmitAnyExpr(E, AggLoc, IsAggLocVolatile, /*IgnoreResult=*/false, IsInitializer); } RValue CodeGenFunction::EmitReferenceBindingToExpr(const Expr* E, QualType DestType, bool IsInitializer) { bool ShouldDestroyTemporaries = false; unsigned OldNumLiveTemporaries = 0; if (const CXXExprWithTemporaries *TE = dyn_cast(E)) { ShouldDestroyTemporaries = TE->shouldDestroyTemporaries(); // Keep track of the current cleanup stack depth. if (ShouldDestroyTemporaries) OldNumLiveTemporaries = LiveTemporaries.size(); E = TE->getSubExpr(); } RValue Val; if (E->isLvalue(getContext()) == Expr::LV_Valid) { // Emit the expr as an lvalue. LValue LV = EmitLValue(E); if (LV.isSimple()) return RValue::get(LV.getAddress()); Val = EmitLoadOfLValue(LV, E->getType()); if (ShouldDestroyTemporaries) { // Pop temporaries. while (LiveTemporaries.size() > OldNumLiveTemporaries) PopCXXTemporary(); } } else { const CXXRecordDecl *BaseClassDecl = 0; const CXXRecordDecl *DerivedClassDecl = 0; if (const CastExpr *CE = dyn_cast(E->IgnoreParenNoopCasts(getContext()))) { if (CE->getCastKind() == CastExpr::CK_DerivedToBase) { E = CE->getSubExpr(); BaseClassDecl = cast(CE->getType()->getAs()->getDecl()); DerivedClassDecl = cast(E->getType()->getAs()->getDecl()); } } Val = EmitAnyExprToTemp(E, /*IsAggLocVolatile=*/false, IsInitializer); if (ShouldDestroyTemporaries) { // Pop temporaries. while (LiveTemporaries.size() > OldNumLiveTemporaries) PopCXXTemporary(); } if (IsInitializer) { // We might have to destroy the temporary variable. if (const RecordType *RT = E->getType()->getAs()) { if (CXXRecordDecl *ClassDecl = dyn_cast(RT->getDecl())) { if (!ClassDecl->hasTrivialDestructor()) { const CXXDestructorDecl *Dtor = ClassDecl->getDestructor(getContext()); { DelayedCleanupBlock scope(*this); EmitCXXDestructorCall(Dtor, Dtor_Complete, Val.getAggregateAddr()); } if (Exceptions) { EHCleanupBlock Cleanup(*this); EmitCXXDestructorCall(Dtor, Dtor_Complete, Val.getAggregateAddr()); } } } } } // Check if need to perform the derived-to-base cast. if (BaseClassDecl) { llvm::Value *Derived = Val.getAggregateAddr(); llvm::Value *Base = GetAddressOfBaseClass(Derived, DerivedClassDecl, BaseClassDecl, /*NullCheckValue=*/false); return RValue::get(Base); } } if (Val.isAggregate()) { Val = RValue::get(Val.getAggregateAddr()); } else { // Create a temporary variable that we can bind the reference to. llvm::Value *Temp = CreateTempAlloca(ConvertTypeForMem(E->getType()), "reftmp"); if (Val.isScalar()) EmitStoreOfScalar(Val.getScalarVal(), Temp, false, E->getType()); else StoreComplexToAddr(Val.getComplexVal(), Temp, false); Val = RValue::get(Temp); } return Val; } /// 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(Elts)) return 0; return cast(Elts->getOperand(Idx))->getZExtValue(); } //===----------------------------------------------------------------------===// // LValue Expression Emission //===----------------------------------------------------------------------===// RValue CodeGenFunction::GetUndefRValue(QualType Ty) { if (Ty->isVoidType()) return RValue::get(0); if (const ComplexType *CTy = Ty->getAs()) { const llvm::Type *EltTy = ConvertType(CTy->getElementType()); llvm::Value *U = llvm::UndefValue::get(EltTy); return RValue::getComplex(std::make_pair(U, U)); } if (hasAggregateLLVMType(Ty)) { const llvm::Type *LTy = llvm::PointerType::getUnqual(ConvertType(Ty)); return RValue::getAggregate(llvm::UndefValue::get(LTy)); } 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 LValue::MakeAddr(llvm::UndefValue::get(Ty), MakeQualifiers(E->getType())); } /// 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::ObjCIsaExprClass: return EmitObjCIsaExpr(cast(E)); case Expr::BinaryOperatorClass: return EmitBinaryOperatorLValue(cast(E)); case Expr::CallExprClass: case Expr::CXXMemberCallExprClass: case Expr::CXXOperatorCallExprClass: return EmitCallExprLValue(cast(E)); case Expr::VAArgExprClass: return EmitVAArgExprLValue(cast(E)); case Expr::DeclRefExprClass: return EmitDeclRefLValue(cast(E)); case Expr::ParenExprClass:return EmitLValue(cast(E)->getSubExpr()); case Expr::PredefinedExprClass: return EmitPredefinedLValue(cast(E)); case Expr::StringLiteralClass: return EmitStringLiteralLValue(cast(E)); case Expr::ObjCEncodeExprClass: return EmitObjCEncodeExprLValue(cast(E)); case Expr::BlockDeclRefExprClass: return EmitBlockDeclRefLValue(cast(E)); case Expr::CXXTemporaryObjectExprClass: case Expr::CXXConstructExprClass: return EmitCXXConstructLValue(cast(E)); case Expr::CXXBindTemporaryExprClass: return EmitCXXBindTemporaryLValue(cast(E)); case Expr::CXXExprWithTemporariesClass: return EmitCXXExprWithTemporariesLValue(cast(E)); case Expr::CXXZeroInitValueExprClass: return EmitNullInitializationLValue(cast(E)); case Expr::CXXDefaultArgExprClass: return EmitLValue(cast(E)->getExpr()); case Expr::CXXTypeidExprClass: return EmitCXXTypeidLValue(cast(E)); case Expr::ObjCMessageExprClass: return EmitObjCMessageExprLValue(cast(E)); case Expr::ObjCIvarRefExprClass: return EmitObjCIvarRefLValue(cast(E)); case Expr::ObjCPropertyRefExprClass: return EmitObjCPropertyRefLValue(cast(E)); case Expr::ObjCImplicitSetterGetterRefExprClass: return EmitObjCKVCRefLValue(cast(E)); case Expr::ObjCSuperExprClass: return EmitObjCSuperExprLValue(cast(E)); case Expr::StmtExprClass: return EmitStmtExprLValue(cast(E)); case Expr::UnaryOperatorClass: return EmitUnaryOpLValue(cast(E)); case Expr::ArraySubscriptExprClass: return EmitArraySubscriptExpr(cast(E)); case Expr::ExtVectorElementExprClass: return EmitExtVectorElementExpr(cast(E)); case Expr::MemberExprClass: return EmitMemberExpr(cast(E)); case Expr::CompoundLiteralExprClass: return EmitCompoundLiteralLValue(cast(E)); case Expr::ConditionalOperatorClass: return EmitConditionalOperatorLValue(cast(E)); case Expr::ChooseExprClass: return EmitLValue(cast(E)->getChosenSubExpr(getContext())); case Expr::ImplicitCastExprClass: case Expr::CStyleCastExprClass: case Expr::CXXFunctionalCastExprClass: case Expr::CXXStaticCastExprClass: case Expr::CXXDynamicCastExprClass: case Expr::CXXReinterpretCastExprClass: case Expr::CXXConstCastExprClass: return EmitCastLValue(cast(E)); } } llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile, QualType Ty) { llvm::LoadInst *Load = Builder.CreateLoad(Addr, "tmp"); if (Volatile) Load->setVolatile(true); // Bool can have different representation in memory than in registers. llvm::Value *V = Load; if (Ty->isBooleanType()) if (V->getType() != llvm::Type::getInt1Ty(VMContext)) V = Builder.CreateTrunc(V, llvm::Type::getInt1Ty(VMContext), "tobool"); return V; } void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr, bool Volatile, QualType Ty) { if (Ty->isBooleanType()) { // Bool can have different representation in memory than in registers. const llvm::PointerType *DstPtr = cast(Addr->getType()); Value = Builder.CreateIntCast(Value, DstPtr->getElementType(), false); } Builder.CreateStore(Value, Addr, Volatile); } /// 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(); const llvm::Type *EltTy = cast(Ptr->getType())->getElementType(); // Simple scalar l-value. if (EltTy->isSingleValueType()) return RValue::get(EmitLoadOfScalar(Ptr, LV.isVolatileQualified(), ExprType)); assert(ExprType->isFunctionType() && "Unknown scalar value"); return RValue::get(Ptr); } 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); if (LV.isPropertyRef()) return EmitLoadOfPropertyRefLValue(LV, ExprType); assert(LV.isKVCRef() && "Unknown LValue type!"); return EmitLoadOfKVCRefLValue(LV, ExprType); } RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV, QualType ExprType) { unsigned StartBit = LV.getBitfieldStartBit(); unsigned BitfieldSize = LV.getBitfieldSize(); llvm::Value *Ptr = LV.getBitfieldAddr(); const llvm::Type *EltTy = cast(Ptr->getType())->getElementType(); unsigned EltTySize = CGM.getTargetData().getTypeSizeInBits(EltTy); // In some cases the bitfield may straddle two memory locations. Currently we // load the entire bitfield, then do the magic to sign-extend it if // necessary. This results in somewhat more code than necessary for the common // case (one load), since two shifts accomplish both the masking and sign // extension. unsigned LowBits = std::min(BitfieldSize, EltTySize - StartBit); llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "tmp"); // Shift to proper location. if (StartBit) Val = Builder.CreateLShr(Val, StartBit, "bf.lo"); // Mask off unused bits. llvm::Constant *LowMask = llvm::ConstantInt::get(VMContext, llvm::APInt::getLowBitsSet(EltTySize, LowBits)); Val = Builder.CreateAnd(Val, LowMask, "bf.lo.cleared"); // Fetch the high bits if necessary. if (LowBits < BitfieldSize) { unsigned HighBits = BitfieldSize - LowBits; llvm::Value *HighPtr = Builder.CreateGEP(Ptr, llvm::ConstantInt::get( llvm::Type::getInt32Ty(VMContext), 1), "bf.ptr.hi"); llvm::Value *HighVal = Builder.CreateLoad(HighPtr, LV.isVolatileQualified(), "tmp"); // Mask off unused bits. llvm::Constant *HighMask = llvm::ConstantInt::get(VMContext, llvm::APInt::getLowBitsSet(EltTySize, HighBits)); HighVal = Builder.CreateAnd(HighVal, HighMask, "bf.lo.cleared"); // Shift to proper location and or in to bitfield value. HighVal = Builder.CreateShl(HighVal, LowBits); Val = Builder.CreateOr(Val, HighVal, "bf.val"); } // Sign extend if necessary. if (LV.isBitfieldSigned()) { llvm::Value *ExtraBits = llvm::ConstantInt::get(EltTy, EltTySize - BitfieldSize); Val = Builder.CreateAShr(Builder.CreateShl(Val, ExtraBits), ExtraBits, "bf.val.sext"); } // The bitfield type and the normal type differ when the storage sizes differ // (currently just _Bool). Val = Builder.CreateIntCast(Val, ConvertType(ExprType), false, "tmp"); return RValue::get(Val); } RValue CodeGenFunction::EmitLoadOfPropertyRefLValue(LValue LV, QualType ExprType) { return EmitObjCPropertyGet(LV.getPropertyRefExpr()); } RValue CodeGenFunction::EmitLoadOfKVCRefLValue(LValue LV, QualType ExprType) { return EmitObjCPropertyGet(LV.getKVCRefExpr()); } // 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(); if (!ExprVT) { unsigned InIdx = getAccessedFieldNo(0, Elts); llvm::Value *Elt = llvm::ConstantInt::get( llvm::Type::getInt32Ty(VMContext), 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 Mask; for (unsigned i = 0; i != NumResultElts; ++i) { unsigned InIdx = getAccessedFieldNo(i, Elts); Mask.push_back(llvm::ConstantInt::get( llvm::Type::getInt32Ty(VMContext), InIdx)); } llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size()); 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); if (Dst.isPropertyRef()) return EmitStoreThroughPropertyRefLValue(Src, Dst, Ty); assert(Dst.isKVCRef() && "Unknown LValue type"); return EmitStoreThroughKVCRefLValue(Src, Dst, Ty); } 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); 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(), Ty); } void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst, QualType Ty, llvm::Value **Result) { unsigned StartBit = Dst.getBitfieldStartBit(); unsigned BitfieldSize = Dst.getBitfieldSize(); llvm::Value *Ptr = Dst.getBitfieldAddr(); const llvm::Type *EltTy = cast(Ptr->getType())->getElementType(); unsigned EltTySize = CGM.getTargetData().getTypeSizeInBits(EltTy); // Get the new value, cast to the appropriate type and masked to exactly the // size of the bit-field. llvm::Value *SrcVal = Src.getScalarVal(); llvm::Value *NewVal = Builder.CreateIntCast(SrcVal, EltTy, false, "tmp"); llvm::Constant *Mask = llvm::ConstantInt::get(VMContext, llvm::APInt::getLowBitsSet(EltTySize, BitfieldSize)); NewVal = Builder.CreateAnd(NewVal, Mask, "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 = SrcVal->getType(); llvm::Value *SrcTrunc = Builder.CreateIntCast(NewVal, SrcTy, false, "bf.reload.val"); // Sign extend if necessary. if (Dst.isBitfieldSigned()) { unsigned SrcTySize = CGM.getTargetData().getTypeSizeInBits(SrcTy); llvm::Value *ExtraBits = llvm::ConstantInt::get(SrcTy, SrcTySize - BitfieldSize); SrcTrunc = Builder.CreateAShr(Builder.CreateShl(SrcTrunc, ExtraBits), ExtraBits, "bf.reload.sext"); } *Result = SrcTrunc; } // In some cases the bitfield may straddle two memory locations. Emit the low // part first and check to see if the high needs to be done. unsigned LowBits = std::min(BitfieldSize, EltTySize - StartBit); llvm::Value *LowVal = Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.prev.low"); // Compute the mask for zero-ing the low part of this bitfield. llvm::Constant *InvMask = llvm::ConstantInt::get(VMContext, ~llvm::APInt::getBitsSet(EltTySize, StartBit, StartBit + LowBits)); // Compute the new low part as // LowVal = (LowVal & InvMask) | (NewVal << StartBit), // with the shift of NewVal implicitly stripping the high bits. llvm::Value *NewLowVal = Builder.CreateShl(NewVal, StartBit, "bf.value.lo"); LowVal = Builder.CreateAnd(LowVal, InvMask, "bf.prev.lo.cleared"); LowVal = Builder.CreateOr(LowVal, NewLowVal, "bf.new.lo"); // Write back. Builder.CreateStore(LowVal, Ptr, Dst.isVolatileQualified()); // If the low part doesn't cover the bitfield emit a high part. if (LowBits < BitfieldSize) { unsigned HighBits = BitfieldSize - LowBits; llvm::Value *HighPtr = Builder.CreateGEP(Ptr, llvm::ConstantInt::get( llvm::Type::getInt32Ty(VMContext), 1), "bf.ptr.hi"); llvm::Value *HighVal = Builder.CreateLoad(HighPtr, Dst.isVolatileQualified(), "bf.prev.hi"); // Compute the mask for zero-ing the high part of this bitfield. llvm::Constant *InvMask = llvm::ConstantInt::get(VMContext, ~llvm::APInt::getLowBitsSet(EltTySize, HighBits)); // Compute the new high part as // HighVal = (HighVal & InvMask) | (NewVal lshr LowBits), // where the high bits of NewVal have already been cleared and the // shift stripping the low bits. llvm::Value *NewHighVal = Builder.CreateLShr(NewVal, LowBits, "bf.value.high"); HighVal = Builder.CreateAnd(HighVal, InvMask, "bf.prev.hi.cleared"); HighVal = Builder.CreateOr(HighVal, NewHighVal, "bf.new.hi"); // Write back. Builder.CreateStore(HighVal, HighPtr, Dst.isVolatileQualified()); } } void CodeGenFunction::EmitStoreThroughPropertyRefLValue(RValue Src, LValue Dst, QualType Ty) { EmitObjCPropertySet(Dst.getPropertyRefExpr(), Src); } void CodeGenFunction::EmitStoreThroughKVCRefLValue(RValue Src, LValue Dst, QualType Ty) { EmitObjCPropertySet(Dst.getKVCRefExpr(), Src); } 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()) { unsigned NumSrcElts = VTy->getNumElements(); unsigned NumDstElts = cast(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 Mask(NumDstElts); for (unsigned i = 0; i != NumSrcElts; ++i) { unsigned InIdx = getAccessedFieldNo(i, Elts); Mask[InIdx] = llvm::ConstantInt::get( llvm::Type::getInt32Ty(VMContext), i); } llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size()); 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 ExtMask; const llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext); 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[0], ExtMask.size()); llvm::Value *ExtSrcVal = Builder.CreateShuffleVector(SrcVal, llvm::UndefValue::get(SrcVal->getType()), ExtMaskV, "tmp"); // build identity llvm::SmallVector 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[0], Mask.size()); 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); const llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext); 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(E)) { LV.SetObjCIvar(LV, true); ObjCIvarRefExpr *Exp = cast(const_cast(E)); LV.setBaseIvarExp(Exp->getBase()); LV.SetObjCArray(LV, E->getType()->isArrayType()); return; } if (const DeclRefExpr *Exp = dyn_cast(E)) { if (const VarDecl *VD = dyn_cast(Exp->getDecl())) { if ((VD->isBlockVarDecl() && !VD->hasLocalStorage()) || VD->isFileVarDecl()) LV.SetGlobalObjCRef(LV, true); } LV.SetObjCArray(LV, E->getType()->isArrayType()); return; } if (const UnaryOperator *Exp = dyn_cast(E)) { setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV); return; } if (const ParenExpr *Exp = dyn_cast(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()->getPointeeType(); if (ExpTy->isRecordType()) LV.SetObjCIvar(LV, false); } return; } if (const ImplicitCastExpr *Exp = dyn_cast(E)) { setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV); return; } if (const CStyleCastExpr *Exp = dyn_cast(E)) { setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV); return; } if (const ArraySubscriptExpr *Exp = dyn_cast(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(LV, 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(LV, false); return; } if (const MemberExpr *Exp = dyn_cast(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(LV, 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"); LValue LV = LValue::MakeAddr(V, CGF.MakeQualifiers(E->getType())); 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()) { // 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"); } } return LValue::MakeAddr(V, CGF.MakeQualifiers(E->getType())); } LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) { const NamedDecl *ND = E->getDecl(); if (const VarDecl *VD = dyn_cast(ND)) { // Check if this is a global variable. if (VD->hasExternalStorage() || VD->isFileVarDecl()) return EmitGlobalVarDeclLValue(*this, E, VD); bool NonGCable = VD->hasLocalStorage() && !VD->hasAttr(); llvm::Value *V = LocalDeclMap[VD]; assert(V && "DeclRefExpr not entered in LocalDeclMap?"); Qualifiers Quals = MakeQualifiers(E->getType()); // local variables do not get their gc attribute set. // local static? if (NonGCable) Quals.removeObjCGCAttr(); if (VD->hasAttr()) { V = Builder.CreateStructGEP(V, 1, "forwarding"); V = Builder.CreateLoad(V); V = Builder.CreateStructGEP(V, getByRefValueLLVMField(VD), VD->getNameAsString()); } if (VD->getType()->isReferenceType()) V = Builder.CreateLoad(V, "tmp"); LValue LV = LValue::MakeAddr(V, Quals); LValue::SetObjCNonGC(LV, NonGCable); setObjCGCLValueClass(getContext(), E, LV); return LV; } if (const FunctionDecl *FD = dyn_cast(ND)) return EmitFunctionDeclLValue(*this, E, FD); if (E->getQualifier()) { // FIXME: the qualifier check does not seem sufficient here return EmitPointerToDataMemberLValue(cast(ND)); } 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) { return LValue::MakeAddr(GetAddrOfBlockDecl(E), MakeQualifiers(E->getType())); } LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) { // __extension__ doesn't affect lvalue-ness. if (E->getOpcode() == UnaryOperator::Extension) return EmitLValue(E->getSubExpr()); QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType()); switch (E->getOpcode()) { default: assert(0 && "Unknown unary operator lvalue!"); case UnaryOperator::Deref: { QualType T = E->getSubExpr()->getType()->getPointeeType(); assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type"); Qualifiers Quals = MakeQualifiers(T); Quals.setAddressSpace(ExprTy.getAddressSpace()); LValue LV = LValue::MakeAddr(EmitScalarExpr(E->getSubExpr()), Quals); // 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()) LValue::SetObjCNonGC(LV, !E->isOBJCGCCandidate(getContext())); return LV; } case UnaryOperator::Real: case UnaryOperator::Imag: { LValue LV = EmitLValue(E->getSubExpr()); unsigned Idx = E->getOpcode() == UnaryOperator::Imag; return LValue::MakeAddr(Builder.CreateStructGEP(LV.getAddress(), Idx, "idx"), MakeQualifiers(ExprTy)); } case UnaryOperator::PreInc: case UnaryOperator::PreDec: return EmitUnsupportedLValue(E, "pre-inc/dec expression"); } } LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) { return LValue::MakeAddr(CGM.GetAddrOfConstantStringFromLiteral(E), Qualifiers()); } LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) { return LValue::MakeAddr(CGM.GetAddrOfConstantStringFromObjCEncode(E), Qualifiers()); } LValue CodeGenFunction::EmitPredefinedFunctionName(unsigned Type) { 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; std::string FunctionName = PredefinedExpr::ComputeName(getContext(), (PredefinedExpr::IdentType)Type, CurCodeDecl); llvm::Constant *C = CGM.GetAddrOfConstantCString(FunctionName, GlobalVarName.c_str()); return LValue::MakeAddr(C, Qualifiers()); } LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) { switch (E->getIdentType()) { default: return EmitUnsupportedLValue(E, "predefined expression"); case PredefinedExpr::Func: case PredefinedExpr::Function: case PredefinedExpr::PrettyFunction: return EmitPredefinedFunctionName(E->getIdentType()); } } 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, llvm::Type::getInt32Ty(VMContext), IdxSigned, "vidx"); return LValue::MakeVectorElt(LHS.getAddress(), Idx, E->getBase()->getType().getCVRQualifiers()); } // The base must be a pointer, which is not an aggregate. Emit it. llvm::Value *Base = EmitScalarExpr(E->getBase()); // Extend or truncate the index type to 32 or 64-bits. unsigned IdxBitwidth = cast(Idx->getType())->getBitWidth(); if (IdxBitwidth != LLVMPointerWidth) Idx = Builder.CreateIntCast(Idx, llvm::IntegerType::get(VMContext, LLVMPointerWidth), IdxSigned, "idxprom"); // 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; if (const VariableArrayType *VAT = getContext().getAsVariableArrayType(E->getType())) { llvm::Value *VLASize = GetVLASize(VAT); Idx = Builder.CreateMul(Idx, VLASize); QualType BaseType = getContext().getBaseElementType(VAT); uint64_t BaseTypeSize = getContext().getTypeSize(BaseType) / 8; Idx = Builder.CreateUDiv(Idx, llvm::ConstantInt::get(Idx->getType(), BaseTypeSize)); Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx"); } else if (const ObjCInterfaceType *OIT = dyn_cast(E->getType())) { llvm::Value *InterfaceSize = llvm::ConstantInt::get(Idx->getType(), getContext().getTypeSize(OIT) / 8); Idx = Builder.CreateMul(Idx, InterfaceSize); const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext); Address = Builder.CreateGEP(Builder.CreateBitCast(Base, i8PTy), Idx, "arrayidx"); Address = Builder.CreateBitCast(Address, Base->getType()); } else { Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx"); } QualType T = E->getBase()->getType()->getPointeeType(); assert(!T.isNull() && "CodeGenFunction::EmitArraySubscriptExpr(): Illegal base type"); Qualifiers Quals = MakeQualifiers(T); Quals.setAddressSpace(E->getBase()->getType().getAddressSpace()); LValue LV = LValue::MakeAddr(Address, Quals); if (getContext().getLangOptions().ObjC1 && getContext().getLangOptions().getGCMode() != LangOptions::NonGC) { LValue::SetObjCNonGC(LV, !E->isOBJCGCCandidate(getContext())); setObjCGCLValueClass(getContext(), E, LV); } return LV; } static llvm::Constant *GenerateConstantVector(llvm::LLVMContext &VMContext, llvm::SmallVector &Elts) { llvm::SmallVector CElts; for (unsigned i = 0, e = Elts.size(); i != e; ++i) CElts.push_back(llvm::ConstantInt::get( llvm::Type::getInt32Ty(VMContext), Elts[i])); return llvm::ConstantVector::get(&CElts[0], CElts.size()); } 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()) { assert(E->getBase()->getType()->isVectorType()); Base = EmitLValue(E->getBase()); } else { const PointerType *PT = E->getBase()->getType()->getAs(); llvm::Value *Ptr = EmitScalarExpr(E->getBase()); Qualifiers Quals = MakeQualifiers(PT->getPointeeType()); Quals.removeObjCGCAttr(); Base = LValue::MakeAddr(Ptr, Quals); } // Encode the element access list into a vector of unsigned indices. llvm::SmallVector Indices; E->getEncodedElementAccess(Indices); if (Base.isSimple()) { llvm::Constant *CV = GenerateConstantVector(VMContext, 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 CElts; const llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext); for (unsigned i = 0, e = Indices.size(); i != e; ++i) { if (isa(BaseElts)) CElts.push_back(llvm::ConstantInt::get(Int32Ty, 0)); else CElts.push_back(cast(BaseElts->getOperand(Indices[i]))); } llvm::Constant *CV = llvm::ConstantVector::get(&CElts[0], CElts.size()); return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV, Base.getVRQualifiers()); } LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) { bool isUnion = false; 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(); if (PTy->getPointeeType()->isUnionType()) isUnion = true; BaseQuals = PTy->getPointeeType().getQualifiers(); } else if (isa(BaseExpr->IgnoreParens()) || isa( BaseExpr->IgnoreParens())) { RValue RV = EmitObjCPropertyGet(BaseExpr); BaseValue = RV.getAggregateAddr(); if (BaseExpr->getType()->isUnionType()) isUnion = true; BaseQuals = BaseExpr->getType().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(); if (BaseTy->isUnionType()) isUnion = true; BaseQuals = BaseTy.getQualifiers(); } NamedDecl *ND = E->getMemberDecl(); if (FieldDecl *Field = dyn_cast(ND)) { LValue LV = EmitLValueForField(BaseValue, Field, isUnion, BaseQuals.getCVRQualifiers()); LValue::SetObjCNonGC(LV, isNonGC); setObjCGCLValueClass(getContext(), E, LV); return LV; } if (VarDecl *VD = dyn_cast(ND)) return EmitGlobalVarDeclLValue(*this, E, VD); if (const FunctionDecl *FD = dyn_cast(ND)) return EmitFunctionDeclLValue(*this, E, FD); assert(false && "Unhandled member declaration!"); return LValue(); } LValue CodeGenFunction::EmitLValueForBitfield(llvm::Value* BaseValue, const FieldDecl* Field, unsigned CVRQualifiers) { CodeGenTypes::BitFieldInfo Info = CGM.getTypes().getBitFieldInfo(Field); // FIXME: CodeGenTypes should expose a method to get the appropriate type for // FieldTy (the appropriate type is ABI-dependent). const llvm::Type *FieldTy = CGM.getTypes().ConvertTypeForMem(Field->getType()); const llvm::PointerType *BaseTy = cast(BaseValue->getType()); unsigned AS = BaseTy->getAddressSpace(); BaseValue = Builder.CreateBitCast(BaseValue, llvm::PointerType::get(FieldTy, AS), "tmp"); llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), Info.FieldNo); llvm::Value *V = Builder.CreateGEP(BaseValue, Idx, "tmp"); return LValue::MakeBitfield(V, Info.Start, Info.Size, Field->getType()->isSignedIntegerType(), Field->getType().getCVRQualifiers()|CVRQualifiers); } LValue CodeGenFunction::EmitLValueForField(llvm::Value* BaseValue, const FieldDecl* Field, bool isUnion, unsigned CVRQualifiers) { if (Field->isBitField()) return EmitLValueForBitfield(BaseValue, Field, CVRQualifiers); unsigned idx = CGM.getTypes().getLLVMFieldNo(Field); llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx, "tmp"); // Match union field type. if (isUnion) { const llvm::Type *FieldTy = CGM.getTypes().ConvertTypeForMem(Field->getType()); const llvm::PointerType * BaseTy = cast(BaseValue->getType()); unsigned AS = BaseTy->getAddressSpace(); V = Builder.CreateBitCast(V, llvm::PointerType::get(FieldTy, AS), "tmp"); } if (Field->getType()->isReferenceType()) V = Builder.CreateLoad(V, "tmp"); Qualifiers Quals = MakeQualifiers(Field->getType()); Quals.addCVRQualifiers(CVRQualifiers); // __weak attribute on a field is ignored. if (Quals.getObjCGCAttr() == Qualifiers::Weak) Quals.removeObjCGCAttr(); return LValue::MakeAddr(V, Quals); } LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr* E){ const llvm::Type *LTy = ConvertType(E->getType()); llvm::Value *DeclPtr = CreateTempAlloca(LTy, ".compoundliteral"); const Expr* InitExpr = E->getInitializer(); LValue Result = LValue::MakeAddr(DeclPtr, MakeQualifiers(E->getType())); if (E->getType()->isComplexType()) EmitComplexExprIntoAddr(InitExpr, DeclPtr, false); else if (hasAggregateLLVMType(E->getType())) EmitAnyExpr(InitExpr, DeclPtr, false); else EmitStoreThroughLValue(EmitAnyExpr(InitExpr), Result, E->getType()); return Result; } LValue CodeGenFunction::EmitConditionalOperatorLValue(const ConditionalOperator* E) { if (E->isLvalue(getContext()) == Expr::LV_Valid) { llvm::BasicBlock *LHSBlock = createBasicBlock("cond.true"); llvm::BasicBlock *RHSBlock = createBasicBlock("cond.false"); llvm::BasicBlock *ContBlock = createBasicBlock("cond.end"); llvm::Value *Cond = EvaluateExprAsBool(E->getCond()); Builder.CreateCondBr(Cond, LHSBlock, RHSBlock); EmitBlock(LHSBlock); LValue LHS = EmitLValue(E->getLHS()); if (!LHS.isSimple()) return EmitUnsupportedLValue(E, "conditional operator"); llvm::Value *Temp = CreateTempAlloca(LHS.getAddress()->getType(),"condtmp"); Builder.CreateStore(LHS.getAddress(), Temp); EmitBranch(ContBlock); EmitBlock(RHSBlock); LValue RHS = EmitLValue(E->getRHS()); if (!RHS.isSimple()) return EmitUnsupportedLValue(E, "conditional operator"); Builder.CreateStore(RHS.getAddress(), Temp); EmitBranch(ContBlock); EmitBlock(ContBlock); Temp = Builder.CreateLoad(Temp, "lv"); return LValue::MakeAddr(Temp, MakeQualifiers(E->getType())); } // ?: here should be an aggregate. assert((hasAggregateLLVMType(E->getType()) && !E->getType()->isAnyComplexType()) && "Unexpected conditional operator!"); llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType())); EmitAggExpr(E, Temp, false); return LValue::MakeAddr(Temp, MakeQualifiers(E->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()) { default: return EmitUnsupportedLValue(E, "unexpected cast lvalue"); case CastExpr::CK_Dynamic: { LValue LV = EmitLValue(E->getSubExpr()); llvm::Value *V = LV.getAddress(); const CXXDynamicCastExpr *DCE = cast(E); return LValue::MakeAddr(EmitDynamicCast(V, DCE), MakeQualifiers(E->getType())); } case CastExpr::CK_NoOp: case CastExpr::CK_ConstructorConversion: case CastExpr::CK_UserDefinedConversion: return EmitLValue(E->getSubExpr()); case CastExpr::CK_DerivedToBase: { const RecordType *DerivedClassTy = E->getSubExpr()->getType()->getAs(); CXXRecordDecl *DerivedClassDecl = cast(DerivedClassTy->getDecl()); const RecordType *BaseClassTy = E->getType()->getAs(); CXXRecordDecl *BaseClassDecl = cast(BaseClassTy->getDecl()); LValue LV = EmitLValue(E->getSubExpr()); // Perform the derived-to-base conversion llvm::Value *Base = GetAddressOfBaseClass(LV.getAddress(), DerivedClassDecl, BaseClassDecl, /*NullCheckValue=*/false); return LValue::MakeAddr(Base, MakeQualifiers(E->getType())); } case CastExpr::CK_ToUnion: { llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType())); EmitAnyExpr(E->getSubExpr(), Temp, false); return LValue::MakeAddr(Temp, MakeQualifiers(E->getType())); } case CastExpr::CK_BaseToDerived: { const RecordType *BaseClassTy = E->getSubExpr()->getType()->getAs(); CXXRecordDecl *BaseClassDecl = cast(BaseClassTy->getDecl()); const RecordType *DerivedClassTy = E->getType()->getAs(); CXXRecordDecl *DerivedClassDecl = cast(DerivedClassTy->getDecl()); LValue LV = EmitLValue(E->getSubExpr()); // Perform the base-to-derived conversion llvm::Value *Derived = GetAddressOfDerivedClass(LV.getAddress(), BaseClassDecl, DerivedClassDecl, /*NullCheckValue=*/false); return LValue::MakeAddr(Derived, MakeQualifiers(E->getType())); } case CastExpr::CK_BitCast: { // This must be a reinterpret_cast (or c-style equivalent). const ExplicitCastExpr *CE = cast(E); LValue LV = EmitLValue(E->getSubExpr()); llvm::Value *V = Builder.CreateBitCast(LV.getAddress(), ConvertType(CE->getTypeAsWritten())); return LValue::MakeAddr(V, MakeQualifiers(E->getType())); } } } LValue CodeGenFunction::EmitNullInitializationLValue( const CXXZeroInitValueExpr *E) { QualType Ty = E->getType(); const llvm::Type *LTy = ConvertTypeForMem(Ty); llvm::AllocaInst *Alloc = CreateTempAlloca(LTy); unsigned Align = getContext().getTypeAlign(Ty)/8; Alloc->setAlignment(Align); LValue lvalue = LValue::MakeAddr(Alloc, Qualifiers()); EmitMemSetToZero(lvalue.getAddress(), Ty); return lvalue; } //===--------------------------------------------------------------------===// // Expression Emission //===--------------------------------------------------------------------===// RValue CodeGenFunction::EmitCallExpr(const CallExpr *E) { // Builtins never have block type. if (E->getCallee()->getType()->isBlockPointerType()) return EmitBlockCallExpr(E); if (const CXXMemberCallExpr *CE = dyn_cast(E)) return EmitCXXMemberCallExpr(CE); const Decl *TargetDecl = 0; if (const ImplicitCastExpr *CE = dyn_cast(E->getCallee())) { if (const DeclRefExpr *DRE = dyn_cast(CE->getSubExpr())) { TargetDecl = DRE->getDecl(); if (const FunctionDecl *FD = dyn_cast(TargetDecl)) if (unsigned builtinID = FD->getBuiltinID()) return EmitBuiltinExpr(FD, builtinID, E); } } if (const CXXOperatorCallExpr *CE = dyn_cast(E)) if (const CXXMethodDecl *MD = dyn_cast_or_null(TargetDecl)) return EmitCXXOperatorMemberCallExpr(CE, MD); if (isa(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(Callee, E->getCallee()->getType(), 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() == BinaryOperator::Comma) { EmitAnyExpr(E->getLHS()); EnsureInsertPoint(); return EmitLValue(E->getRHS()); } if (E->getOpcode() == BinaryOperator::PtrMemD || E->getOpcode() == BinaryOperator::PtrMemI) return EmitPointerToDataMemberBinaryExpr(E); // Can only get l-value for binary operator expressions which are a // simple assignment of aggregate type. if (E->getOpcode() != BinaryOperator::Assign) return EmitUnsupportedLValue(E, "binary l-value expression"); if (!hasAggregateLLVMType(E->getType())) { // Emit the LHS as an l-value. LValue LV = EmitLValue(E->getLHS()); llvm::Value *RHS = EmitScalarExpr(E->getRHS()); EmitStoreOfScalar(RHS, LV.getAddress(), LV.isVolatileQualified(), E->getType()); return LV; } llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType())); EmitAggExpr(E, Temp, false); // FIXME: Are these qualifiers correct? return LValue::MakeAddr(Temp, MakeQualifiers(E->getType())); } LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) { RValue RV = EmitCallExpr(E); if (!RV.isScalar()) return LValue::MakeAddr(RV.getAggregateAddr(),MakeQualifiers(E->getType())); assert(E->getCallReturnType()->isReferenceType() && "Can't have a scalar return unless the return type is a " "reference type!"); return LValue::MakeAddr(RV.getScalarVal(), MakeQualifiers(E->getType())); } LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) { // FIXME: This shouldn't require another copy. llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType())); EmitAggExpr(E, Temp, false); return LValue::MakeAddr(Temp, MakeQualifiers(E->getType())); } LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) { llvm::Value *Temp = CreateTempAlloca(ConvertTypeForMem(E->getType()), "tmp"); EmitCXXConstructExpr(Temp, E); return LValue::MakeAddr(Temp, MakeQualifiers(E->getType())); } LValue CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) { llvm::Value *Temp = EmitCXXTypeidExpr(E); return LValue::MakeAddr(Temp, MakeQualifiers(E->getType())); } LValue CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) { LValue LV = EmitLValue(E->getSubExpr()); PushCXXTemporary(E->getTemporary(), LV.getAddress()); return LV; } LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) { // Can only get l-value for message expression returning aggregate type RValue RV = EmitObjCMessageExpr(E); // FIXME: can this be volatile? return LValue::MakeAddr(RV.getAggregateAddr(), MakeQualifiers(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::EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E) { // This is a special l-value that just issues sends when we load or store // through it. return LValue::MakePropertyRef(E, E->getType().getCVRQualifiers()); } LValue CodeGenFunction::EmitObjCKVCRefLValue( const ObjCImplicitSetterGetterRefExpr *E) { // This is a special l-value that just issues sends when we load or store // through it. return LValue::MakeKVCRef(E, E->getType().getCVRQualifiers()); } LValue CodeGenFunction::EmitObjCSuperExprLValue(const ObjCSuperExpr *E) { return EmitUnsupportedLValue(E, "use of super"); } LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) { // Can only get l-value for message expression returning aggregate type RValue RV = EmitAnyExprToTemp(E); // FIXME: can this be volatile? return LValue::MakeAddr(RV.getAggregateAddr(), MakeQualifiers(E->getType())); } LValue CodeGenFunction::EmitPointerToDataMemberLValue(const FieldDecl *Field) { const CXXRecordDecl *ClassDecl = cast(Field->getDeclContext()); QualType NNSpecTy = getContext().getCanonicalType( getContext().getTypeDeclType(const_cast(ClassDecl))); NNSpecTy = getContext().getPointerType(NNSpecTy); llvm::Value *V = llvm::Constant::getNullValue(ConvertType(NNSpecTy)); LValue MemExpLV = EmitLValueForField(V, Field, /*isUnion=*/false, /*Qualifiers=*/0); const llvm::Type *ResultType = ConvertType(getContext().getPointerDiffType()); V = Builder.CreatePtrToInt(MemExpLV.getAddress(), ResultType, "datamember"); return LValue::MakeAddr(V, MakeQualifiers(Field->getType())); } RValue CodeGenFunction::EmitCall(llvm::Value *Callee, QualType CalleeType, 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); QualType FnType = cast(CalleeType)->getPointeeType(); QualType ResultType = cast(FnType)->getResultType(); CallArgList Args; EmitCallArgs(Args, dyn_cast(FnType), ArgBeg, ArgEnd); // FIXME: We should not need to do this, it should be part of the function // type. unsigned CallingConvention = 0; if (const llvm::Function *F = dyn_cast(Callee->stripPointerCasts())) CallingConvention = F->getCallingConv(); return EmitCall(CGM.getTypes().getFunctionInfo(ResultType, Args, CallingConvention), Callee, Args, TargetDecl); } LValue CodeGenFunction:: EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) { llvm::Value *BaseV; if (E->getOpcode() == BinaryOperator::PtrMemI) BaseV = EmitScalarExpr(E->getLHS()); else BaseV = EmitLValue(E->getLHS()).getAddress(); const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(getLLVMContext()); BaseV = Builder.CreateBitCast(BaseV, i8Ty); llvm::Value *OffsetV = EmitScalarExpr(E->getRHS()); llvm::Value *AddV = Builder.CreateInBoundsGEP(BaseV, OffsetV, "add.ptr"); QualType Ty = E->getRHS()->getType(); Ty = Ty->getAs()->getPointeeType(); const llvm::Type *PType = ConvertType(getContext().getPointerType(Ty)); AddV = Builder.CreateBitCast(AddV, PType); return LValue::MakeAddr(AddV, MakeQualifiers(Ty)); }