| //===--- CGExprScalar.cpp - Emit LLVM Code for Scalar Exprs ---------------===// |
| // |
| // 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 with scalar LLVM types as LLVM code. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "CodeGenFunction.h" |
| #include "CodeGenModule.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/StmtVisitor.h" |
| #include "clang/Basic/TargetInfo.h" |
| #include "llvm/Constants.h" |
| #include "llvm/Function.h" |
| #include "llvm/GlobalVariable.h" |
| #include "llvm/Intrinsics.h" |
| #include "llvm/Support/Compiler.h" |
| #include "llvm/Support/CFG.h" |
| #include <cstdarg> |
| |
| using namespace clang; |
| using namespace CodeGen; |
| using llvm::Value; |
| |
| //===----------------------------------------------------------------------===// |
| // Scalar Expression Emitter |
| //===----------------------------------------------------------------------===// |
| |
| struct BinOpInfo { |
| Value *LHS; |
| Value *RHS; |
| QualType Ty; // Computation Type. |
| const BinaryOperator *E; |
| }; |
| |
| namespace { |
| class VISIBILITY_HIDDEN ScalarExprEmitter |
| : public StmtVisitor<ScalarExprEmitter, Value*> { |
| CodeGenFunction &CGF; |
| CGBuilderTy &Builder; |
| |
| public: |
| |
| ScalarExprEmitter(CodeGenFunction &cgf) : CGF(cgf), |
| Builder(CGF.Builder) { |
| } |
| |
| //===--------------------------------------------------------------------===// |
| // Utilities |
| //===--------------------------------------------------------------------===// |
| |
| const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } |
| LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } |
| |
| Value *EmitLoadOfLValue(LValue LV, QualType T) { |
| return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); |
| } |
| |
| /// EmitLoadOfLValue - Given an expression with complex type that represents a |
| /// value l-value, this method emits the address of the l-value, then loads |
| /// and returns the result. |
| Value *EmitLoadOfLValue(const Expr *E) { |
| // FIXME: Volatile |
| return EmitLoadOfLValue(EmitLValue(E), E->getType()); |
| } |
| |
| /// EmitConversionToBool - Convert the specified expression value to a |
| /// boolean (i1) truth value. This is equivalent to "Val != 0". |
| Value *EmitConversionToBool(Value *Src, QualType DstTy); |
| |
| /// EmitScalarConversion - Emit a conversion from the specified type to the |
| /// specified destination type, both of which are LLVM scalar types. |
| Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); |
| |
| /// EmitComplexToScalarConversion - Emit a conversion from the specified |
| /// complex type to the specified destination type, where the destination |
| /// type is an LLVM scalar type. |
| Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, |
| QualType SrcTy, QualType DstTy); |
| |
| //===--------------------------------------------------------------------===// |
| // Visitor Methods |
| //===--------------------------------------------------------------------===// |
| |
| Value *VisitStmt(Stmt *S) { |
| S->dump(CGF.getContext().getSourceManager()); |
| assert(0 && "Stmt can't have complex result type!"); |
| return 0; |
| } |
| Value *VisitExpr(Expr *S); |
| Value *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } |
| |
| // Leaves. |
| Value *VisitIntegerLiteral(const IntegerLiteral *E) { |
| return llvm::ConstantInt::get(E->getValue()); |
| } |
| Value *VisitFloatingLiteral(const FloatingLiteral *E) { |
| return llvm::ConstantFP::get(E->getValue()); |
| } |
| Value *VisitCharacterLiteral(const CharacterLiteral *E) { |
| return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); |
| } |
| Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { |
| return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); |
| } |
| Value *VisitCXXZeroInitValueExpr(const CXXZeroInitValueExpr *E) { |
| return llvm::Constant::getNullValue(ConvertType(E->getType())); |
| } |
| Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) { |
| return llvm::ConstantInt::get(ConvertType(E->getType()), |
| CGF.getContext().typesAreCompatible( |
| E->getArgType1(), E->getArgType2())); |
| } |
| Value *VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E); |
| Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { |
| llvm::Value *V = |
| llvm::ConstantInt::get(llvm::Type::Int32Ty, |
| CGF.GetIDForAddrOfLabel(E->getLabel())); |
| |
| return Builder.CreateIntToPtr(V, ConvertType(E->getType())); |
| } |
| |
| // l-values. |
| Value *VisitDeclRefExpr(DeclRefExpr *E) { |
| if (const EnumConstantDecl *EC = dyn_cast<EnumConstantDecl>(E->getDecl())) |
| return llvm::ConstantInt::get(EC->getInitVal()); |
| return EmitLoadOfLValue(E); |
| } |
| Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { |
| return CGF.EmitObjCSelectorExpr(E); |
| } |
| Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { |
| return CGF.EmitObjCProtocolExpr(E); |
| } |
| Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { |
| return EmitLoadOfLValue(E); |
| } |
| Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { |
| return EmitLoadOfLValue(E); |
| } |
| Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { |
| return CGF.EmitObjCMessageExpr(E).getScalarVal(); |
| } |
| |
| Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); |
| Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); |
| Value *VisitMemberExpr(Expr *E) { return EmitLoadOfLValue(E); } |
| Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } |
| Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { |
| return EmitLoadOfLValue(E); |
| } |
| Value *VisitStringLiteral(Expr *E) { return EmitLValue(E).getAddress(); } |
| Value *VisitPredefinedExpr(Expr *E) { return EmitLValue(E).getAddress(); } |
| |
| Value *VisitInitListExpr(InitListExpr *E) { |
| unsigned NumInitElements = E->getNumInits(); |
| |
| const llvm::VectorType *VType = |
| dyn_cast<llvm::VectorType>(ConvertType(E->getType())); |
| |
| // We have a scalar in braces. Just use the first element. |
| if (!VType) |
| return Visit(E->getInit(0)); |
| |
| if (E->hadDesignators()) { |
| CGF.ErrorUnsupported(E, "initializer list with designators"); |
| return llvm::UndefValue::get(CGF.ConvertType(E->getType())); |
| } |
| |
| unsigned NumVectorElements = VType->getNumElements(); |
| const llvm::Type *ElementType = VType->getElementType(); |
| |
| // Emit individual vector element stores. |
| llvm::Value *V = llvm::UndefValue::get(VType); |
| |
| // Emit initializers |
| unsigned i; |
| for (i = 0; i < NumInitElements; ++i) { |
| Value *NewV = Visit(E->getInit(i)); |
| Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); |
| V = Builder.CreateInsertElement(V, NewV, Idx); |
| } |
| |
| // Emit remaining default initializers |
| for (/* Do not initialize i*/; i < NumVectorElements; ++i) { |
| Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); |
| llvm::Value *NewV = llvm::Constant::getNullValue(ElementType); |
| V = Builder.CreateInsertElement(V, NewV, Idx); |
| } |
| |
| return V; |
| } |
| |
| Value *VisitImplicitCastExpr(const ImplicitCastExpr *E); |
| Value *VisitCastExpr(const CastExpr *E) { |
| return EmitCastExpr(E->getSubExpr(), E->getType()); |
| } |
| Value *EmitCastExpr(const Expr *E, QualType T); |
| |
| Value *VisitCallExpr(const CallExpr *E) { |
| return CGF.EmitCallExpr(E).getScalarVal(); |
| } |
| |
| Value *VisitStmtExpr(const StmtExpr *E); |
| |
| // Unary Operators. |
| Value *VisitPrePostIncDec(const UnaryOperator *E, bool isInc, bool isPre); |
| Value *VisitUnaryPostDec(const UnaryOperator *E) { |
| return VisitPrePostIncDec(E, false, false); |
| } |
| Value *VisitUnaryPostInc(const UnaryOperator *E) { |
| return VisitPrePostIncDec(E, true, false); |
| } |
| Value *VisitUnaryPreDec(const UnaryOperator *E) { |
| return VisitPrePostIncDec(E, false, true); |
| } |
| Value *VisitUnaryPreInc(const UnaryOperator *E) { |
| return VisitPrePostIncDec(E, true, true); |
| } |
| Value *VisitUnaryAddrOf(const UnaryOperator *E) { |
| return EmitLValue(E->getSubExpr()).getAddress(); |
| } |
| Value *VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); } |
| Value *VisitUnaryPlus(const UnaryOperator *E) { |
| return Visit(E->getSubExpr()); |
| } |
| Value *VisitUnaryMinus (const UnaryOperator *E); |
| Value *VisitUnaryNot (const UnaryOperator *E); |
| Value *VisitUnaryLNot (const UnaryOperator *E); |
| Value *VisitUnaryReal (const UnaryOperator *E); |
| Value *VisitUnaryImag (const UnaryOperator *E); |
| Value *VisitUnaryExtension(const UnaryOperator *E) { |
| return Visit(E->getSubExpr()); |
| } |
| Value *VisitUnaryOffsetOf(const UnaryOperator *E); |
| Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { |
| return Visit(DAE->getExpr()); |
| } |
| |
| // Binary Operators. |
| Value *EmitMul(const BinOpInfo &Ops) { |
| return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); |
| } |
| Value *EmitDiv(const BinOpInfo &Ops); |
| Value *EmitRem(const BinOpInfo &Ops); |
| Value *EmitAdd(const BinOpInfo &Ops); |
| Value *EmitSub(const BinOpInfo &Ops); |
| Value *EmitShl(const BinOpInfo &Ops); |
| Value *EmitShr(const BinOpInfo &Ops); |
| Value *EmitAnd(const BinOpInfo &Ops) { |
| return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); |
| } |
| Value *EmitXor(const BinOpInfo &Ops) { |
| return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); |
| } |
| Value *EmitOr (const BinOpInfo &Ops) { |
| return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); |
| } |
| |
| BinOpInfo EmitBinOps(const BinaryOperator *E); |
| Value *EmitCompoundAssign(const CompoundAssignOperator *E, |
| Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); |
| |
| // Binary operators and binary compound assignment operators. |
| #define HANDLEBINOP(OP) \ |
| Value *VisitBin ## OP(const BinaryOperator *E) { \ |
| return Emit ## OP(EmitBinOps(E)); \ |
| } \ |
| Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ |
| return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ |
| } |
| HANDLEBINOP(Mul); |
| HANDLEBINOP(Div); |
| HANDLEBINOP(Rem); |
| HANDLEBINOP(Add); |
| HANDLEBINOP(Sub); |
| HANDLEBINOP(Shl); |
| HANDLEBINOP(Shr); |
| HANDLEBINOP(And); |
| HANDLEBINOP(Xor); |
| HANDLEBINOP(Or); |
| #undef HANDLEBINOP |
| |
| // Comparisons. |
| Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, |
| unsigned SICmpOpc, unsigned FCmpOpc); |
| #define VISITCOMP(CODE, UI, SI, FP) \ |
| Value *VisitBin##CODE(const BinaryOperator *E) { \ |
| return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ |
| llvm::FCmpInst::FP); } |
| VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT); |
| VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT); |
| VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE); |
| VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE); |
| VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ); |
| VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE); |
| #undef VISITCOMP |
| |
| Value *VisitBinAssign (const BinaryOperator *E); |
| |
| Value *VisitBinLAnd (const BinaryOperator *E); |
| Value *VisitBinLOr (const BinaryOperator *E); |
| Value *VisitBinComma (const BinaryOperator *E); |
| |
| // Other Operators. |
| Value *VisitConditionalOperator(const ConditionalOperator *CO); |
| Value *VisitChooseExpr(ChooseExpr *CE); |
| Value *VisitOverloadExpr(OverloadExpr *OE); |
| Value *VisitVAArgExpr(VAArgExpr *VE); |
| Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { |
| return CGF.EmitObjCStringLiteral(E); |
| } |
| Value *VisitObjCEncodeExpr(const ObjCEncodeExpr *E); |
| }; |
| } // end anonymous namespace. |
| |
| //===----------------------------------------------------------------------===// |
| // Utilities |
| //===----------------------------------------------------------------------===// |
| |
| /// EmitConversionToBool - Convert the specified expression value to a |
| /// boolean (i1) truth value. This is equivalent to "Val != 0". |
| Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { |
| assert(SrcType->isCanonical() && "EmitScalarConversion strips typedefs"); |
| |
| if (SrcType->isRealFloatingType()) { |
| // Compare against 0.0 for fp scalars. |
| llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); |
| return Builder.CreateFCmpUNE(Src, Zero, "tobool"); |
| } |
| |
| assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && |
| "Unknown scalar type to convert"); |
| |
| // Because of the type rules of C, we often end up computing a logical value, |
| // then zero extending it to int, then wanting it as a logical value again. |
| // Optimize this common case. |
| if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) { |
| if (ZI->getOperand(0)->getType() == llvm::Type::Int1Ty) { |
| Value *Result = ZI->getOperand(0); |
| // If there aren't any more uses, zap the instruction to save space. |
| // Note that there can be more uses, for example if this |
| // is the result of an assignment. |
| if (ZI->use_empty()) |
| ZI->eraseFromParent(); |
| return Result; |
| } |
| } |
| |
| // Compare against an integer or pointer null. |
| llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); |
| return Builder.CreateICmpNE(Src, Zero, "tobool"); |
| } |
| |
| /// EmitScalarConversion - Emit a conversion from the specified type to the |
| /// specified destination type, both of which are LLVM scalar types. |
| Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, |
| QualType DstType) { |
| SrcType = CGF.getContext().getCanonicalType(SrcType); |
| DstType = CGF.getContext().getCanonicalType(DstType); |
| if (SrcType == DstType) return Src; |
| |
| if (DstType->isVoidType()) return 0; |
| |
| // Handle conversions to bool first, they are special: comparisons against 0. |
| if (DstType->isBooleanType()) |
| return EmitConversionToBool(Src, SrcType); |
| |
| const llvm::Type *DstTy = ConvertType(DstType); |
| |
| // Ignore conversions like int -> uint. |
| if (Src->getType() == DstTy) |
| return Src; |
| |
| // Handle pointer conversions next: pointers can only be converted |
| // to/from other pointers and integers. Check for pointer types in |
| // terms of LLVM, as some native types (like Obj-C id) may map to a |
| // pointer type. |
| if (isa<llvm::PointerType>(DstTy)) { |
| // The source value may be an integer, or a pointer. |
| if (isa<llvm::PointerType>(Src->getType())) |
| return Builder.CreateBitCast(Src, DstTy, "conv"); |
| assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); |
| return Builder.CreateIntToPtr(Src, DstTy, "conv"); |
| } |
| |
| if (isa<llvm::PointerType>(Src->getType())) { |
| // Must be an ptr to int cast. |
| assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); |
| return Builder.CreatePtrToInt(Src, DstTy, "conv"); |
| } |
| |
| // A scalar can be splatted to an extended vector of the same element type |
| if (DstType->isExtVectorType() && !isa<VectorType>(SrcType) && |
| cast<llvm::VectorType>(DstTy)->getElementType() == Src->getType()) |
| return CGF.EmitVector(&Src, DstType->getAsVectorType()->getNumElements(), |
| true); |
| |
| // Allow bitcast from vector to integer/fp of the same size. |
| if (isa<llvm::VectorType>(Src->getType()) || |
| isa<llvm::VectorType>(DstTy)) |
| return Builder.CreateBitCast(Src, DstTy, "conv"); |
| |
| // Finally, we have the arithmetic types: real int/float. |
| if (isa<llvm::IntegerType>(Src->getType())) { |
| bool InputSigned = SrcType->isSignedIntegerType(); |
| if (isa<llvm::IntegerType>(DstTy)) |
| return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); |
| else if (InputSigned) |
| return Builder.CreateSIToFP(Src, DstTy, "conv"); |
| else |
| return Builder.CreateUIToFP(Src, DstTy, "conv"); |
| } |
| |
| assert(Src->getType()->isFloatingPoint() && "Unknown real conversion"); |
| if (isa<llvm::IntegerType>(DstTy)) { |
| if (DstType->isSignedIntegerType()) |
| return Builder.CreateFPToSI(Src, DstTy, "conv"); |
| else |
| return Builder.CreateFPToUI(Src, DstTy, "conv"); |
| } |
| |
| assert(DstTy->isFloatingPoint() && "Unknown real conversion"); |
| if (DstTy->getTypeID() < Src->getType()->getTypeID()) |
| return Builder.CreateFPTrunc(Src, DstTy, "conv"); |
| else |
| return Builder.CreateFPExt(Src, DstTy, "conv"); |
| } |
| |
| /// EmitComplexToScalarConversion - Emit a conversion from the specified |
| /// complex type to the specified destination type, where the destination |
| /// type is an LLVM scalar type. |
| Value *ScalarExprEmitter:: |
| EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, |
| QualType SrcTy, QualType DstTy) { |
| // Get the source element type. |
| SrcTy = SrcTy->getAsComplexType()->getElementType(); |
| |
| // Handle conversions to bool first, they are special: comparisons against 0. |
| if (DstTy->isBooleanType()) { |
| // Complex != 0 -> (Real != 0) | (Imag != 0) |
| Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); |
| Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); |
| return Builder.CreateOr(Src.first, Src.second, "tobool"); |
| } |
| |
| // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, |
| // the imaginary part of the complex value is discarded and the value of the |
| // real part is converted according to the conversion rules for the |
| // corresponding real type. |
| return EmitScalarConversion(Src.first, SrcTy, DstTy); |
| } |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Visitor Methods |
| //===----------------------------------------------------------------------===// |
| |
| Value *ScalarExprEmitter::VisitExpr(Expr *E) { |
| CGF.ErrorUnsupported(E, "scalar expression"); |
| if (E->getType()->isVoidType()) |
| return 0; |
| return llvm::UndefValue::get(CGF.ConvertType(E->getType())); |
| } |
| |
| Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { |
| llvm::SmallVector<llvm::Constant*, 32> indices; |
| for (unsigned i = 2; i < E->getNumSubExprs(); i++) { |
| indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i)))); |
| } |
| Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); |
| Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); |
| Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size()); |
| return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); |
| } |
| |
| Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { |
| // Emit subscript expressions in rvalue context's. For most cases, this just |
| // loads the lvalue formed by the subscript expr. However, we have to be |
| // careful, because the base of a vector subscript is occasionally an rvalue, |
| // so we can't get it as an lvalue. |
| if (!E->getBase()->getType()->isVectorType()) |
| return EmitLoadOfLValue(E); |
| |
| // Handle the vector case. The base must be a vector, the index must be an |
| // integer value. |
| Value *Base = Visit(E->getBase()); |
| Value *Idx = Visit(E->getIdx()); |
| |
| // FIXME: Convert Idx to i32 type. |
| return Builder.CreateExtractElement(Base, Idx, "vecext"); |
| } |
| |
| /// VisitImplicitCastExpr - Implicit casts are the same as normal casts, but |
| /// also handle things like function to pointer-to-function decay, and array to |
| /// pointer decay. |
| Value *ScalarExprEmitter::VisitImplicitCastExpr(const ImplicitCastExpr *E) { |
| const Expr *Op = E->getSubExpr(); |
| |
| // If this is due to array->pointer conversion, emit the array expression as |
| // an l-value. |
| if (Op->getType()->isArrayType()) { |
| // FIXME: For now we assume that all source arrays map to LLVM arrays. This |
| // will not true when we add support for VLAs. |
| Value *V = EmitLValue(Op).getAddress(); // Bitfields can't be arrays. |
| |
| if (!(isa<llvm::PointerType>(V->getType()) && |
| isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) |
| ->getElementType()))) { |
| CGF.ErrorUnsupported(E, "variable-length array cast", true); |
| if (E->getType()->isVoidType()) |
| return 0; |
| return llvm::UndefValue::get(CGF.ConvertType(E->getType())); |
| } |
| V = Builder.CreateStructGEP(V, 0, "arraydecay"); |
| |
| // The resultant pointer type can be implicitly casted to other pointer |
| // types as well (e.g. void*) and can be implicitly converted to integer. |
| const llvm::Type *DestTy = ConvertType(E->getType()); |
| if (V->getType() != DestTy) { |
| if (isa<llvm::PointerType>(DestTy)) |
| V = Builder.CreateBitCast(V, DestTy, "ptrconv"); |
| else { |
| assert(isa<llvm::IntegerType>(DestTy) && "Unknown array decay"); |
| V = Builder.CreatePtrToInt(V, DestTy, "ptrconv"); |
| } |
| } |
| return V; |
| |
| } else if (E->getType()->isReferenceType()) { |
| return EmitLValue(Op).getAddress(); |
| } |
| |
| return EmitCastExpr(Op, E->getType()); |
| } |
| |
| |
| // VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts |
| // have to handle a more broad range of conversions than explicit casts, as they |
| // handle things like function to ptr-to-function decay etc. |
| Value *ScalarExprEmitter::EmitCastExpr(const Expr *E, QualType DestTy) { |
| // Handle cases where the source is an non-complex type. |
| |
| if (!CGF.hasAggregateLLVMType(E->getType())) { |
| Value *Src = Visit(const_cast<Expr*>(E)); |
| |
| // Use EmitScalarConversion to perform the conversion. |
| return EmitScalarConversion(Src, E->getType(), DestTy); |
| } |
| |
| if (E->getType()->isAnyComplexType()) { |
| // Handle cases where the source is a complex type. |
| return EmitComplexToScalarConversion(CGF.EmitComplexExpr(E), E->getType(), |
| DestTy); |
| } |
| |
| // Okay, this is a cast from an aggregate. It must be a cast to void. Just |
| // evaluate the result and return. |
| CGF.EmitAggExpr(E, 0, false); |
| return 0; |
| } |
| |
| Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { |
| return CGF.EmitCompoundStmt(*E->getSubStmt(), |
| !E->getType()->isVoidType()).getScalarVal(); |
| } |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Unary Operators |
| //===----------------------------------------------------------------------===// |
| |
| Value *ScalarExprEmitter::VisitPrePostIncDec(const UnaryOperator *E, |
| bool isInc, bool isPre) { |
| LValue LV = EmitLValue(E->getSubExpr()); |
| // FIXME: Handle volatile! |
| Value *InVal = CGF.EmitLoadOfLValue(LV, // false |
| E->getSubExpr()->getType()).getScalarVal(); |
| |
| int AmountVal = isInc ? 1 : -1; |
| |
| Value *NextVal; |
| if (isa<llvm::PointerType>(InVal->getType())) { |
| // FIXME: This isn't right for VLAs. |
| NextVal = llvm::ConstantInt::get(llvm::Type::Int32Ty, AmountVal); |
| NextVal = Builder.CreateGEP(InVal, NextVal, "ptrincdec"); |
| } else { |
| // Add the inc/dec to the real part. |
| if (isa<llvm::IntegerType>(InVal->getType())) |
| NextVal = llvm::ConstantInt::get(InVal->getType(), AmountVal); |
| else if (InVal->getType() == llvm::Type::FloatTy) |
| NextVal = |
| llvm::ConstantFP::get(llvm::APFloat(static_cast<float>(AmountVal))); |
| else if (InVal->getType() == llvm::Type::DoubleTy) |
| NextVal = |
| llvm::ConstantFP::get(llvm::APFloat(static_cast<double>(AmountVal))); |
| else { |
| llvm::APFloat F(static_cast<float>(AmountVal)); |
| bool ignored; |
| F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, |
| &ignored); |
| NextVal = llvm::ConstantFP::get(F); |
| } |
| NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); |
| } |
| |
| // Store the updated result through the lvalue. |
| CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, |
| E->getSubExpr()->getType()); |
| |
| // If this is a postinc, return the value read from memory, otherwise use the |
| // updated value. |
| return isPre ? NextVal : InVal; |
| } |
| |
| |
| Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { |
| Value *Op = Visit(E->getSubExpr()); |
| return Builder.CreateNeg(Op, "neg"); |
| } |
| |
| Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { |
| Value *Op = Visit(E->getSubExpr()); |
| return Builder.CreateNot(Op, "neg"); |
| } |
| |
| Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { |
| // Compare operand to zero. |
| Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); |
| |
| // Invert value. |
| // TODO: Could dynamically modify easy computations here. For example, if |
| // the operand is an icmp ne, turn into icmp eq. |
| BoolVal = Builder.CreateNot(BoolVal, "lnot"); |
| |
| // ZExt result to int. |
| return Builder.CreateZExt(BoolVal, CGF.LLVMIntTy, "lnot.ext"); |
| } |
| |
| /// VisitSizeOfAlignOfExpr - Return the size or alignment of the type of |
| /// argument of the sizeof expression as an integer. |
| Value * |
| ScalarExprEmitter::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) { |
| QualType RetType = E->getType(); |
| assert(RetType->isIntegerType() && "Result type must be an integer!"); |
| uint32_t ResultWidth = |
| static_cast<uint32_t>(CGF.getContext().getTypeSize(RetType)); |
| |
| QualType TypeToSize = E->getTypeOfArgument(); |
| // sizeof(void) and __alignof__(void) = 1 as a gcc extension. Also |
| // for function types. |
| // FIXME: what is alignof a function type in gcc? |
| if (TypeToSize->isVoidType() || TypeToSize->isFunctionType()) |
| return llvm::ConstantInt::get(llvm::APInt(ResultWidth, 1)); |
| |
| /// FIXME: This doesn't handle VLAs yet! |
| std::pair<uint64_t, unsigned> Info = CGF.getContext().getTypeInfo(TypeToSize); |
| |
| uint64_t Val = E->isSizeOf() ? Info.first : Info.second; |
| Val /= 8; // Return size in bytes, not bits. |
| |
| return llvm::ConstantInt::get(llvm::APInt(ResultWidth, Val)); |
| } |
| |
| Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { |
| Expr *Op = E->getSubExpr(); |
| if (Op->getType()->isAnyComplexType()) |
| return CGF.EmitComplexExpr(Op).first; |
| return Visit(Op); |
| } |
| Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { |
| Expr *Op = E->getSubExpr(); |
| if (Op->getType()->isAnyComplexType()) |
| return CGF.EmitComplexExpr(Op).second; |
| |
| // __imag on a scalar returns zero. Emit it the subexpr to ensure side |
| // effects are evaluated. |
| CGF.EmitScalarExpr(Op); |
| return llvm::Constant::getNullValue(ConvertType(E->getType())); |
| } |
| |
| Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) |
| { |
| int64_t Val = E->evaluateOffsetOf(CGF.getContext()); |
| |
| assert(E->getType()->isIntegerType() && "Result type must be an integer!"); |
| |
| uint32_t ResultWidth = |
| static_cast<uint32_t>(CGF.getContext().getTypeSize(E->getType())); |
| return llvm::ConstantInt::get(llvm::APInt(ResultWidth, Val)); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Binary Operators |
| //===----------------------------------------------------------------------===// |
| |
| BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { |
| BinOpInfo Result; |
| Result.LHS = Visit(E->getLHS()); |
| Result.RHS = Visit(E->getRHS()); |
| Result.Ty = E->getType(); |
| Result.E = E; |
| return Result; |
| } |
| |
| Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, |
| Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { |
| QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType(); |
| |
| BinOpInfo OpInfo; |
| |
| // Load the LHS and RHS operands. |
| LValue LHSLV = EmitLValue(E->getLHS()); |
| OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); |
| |
| // Determine the computation type. If the RHS is complex, then this is one of |
| // the add/sub/mul/div operators. All of these operators can be computed in |
| // with just their real component even though the computation domain really is |
| // complex. |
| QualType ComputeType = E->getComputationType(); |
| |
| // If the computation type is complex, then the RHS is complex. Emit the RHS. |
| if (const ComplexType *CT = ComputeType->getAsComplexType()) { |
| ComputeType = CT->getElementType(); |
| |
| // Emit the RHS, only keeping the real component. |
| OpInfo.RHS = CGF.EmitComplexExpr(E->getRHS()).first; |
| RHSTy = RHSTy->getAsComplexType()->getElementType(); |
| } else { |
| // Otherwise the RHS is a simple scalar value. |
| OpInfo.RHS = Visit(E->getRHS()); |
| } |
| |
| QualType LComputeTy, RComputeTy, ResultTy; |
| |
| // Compound assignment does not contain enough information about all |
| // the types involved for pointer arithmetic cases. Figure it out |
| // here for now. |
| if (E->getLHS()->getType()->isPointerType()) { |
| // Pointer arithmetic cases: ptr +=,-= int and ptr -= ptr, |
| assert((E->getOpcode() == BinaryOperator::AddAssign || |
| E->getOpcode() == BinaryOperator::SubAssign) && |
| "Invalid compound assignment operator on pointer type."); |
| LComputeTy = E->getLHS()->getType(); |
| |
| if (E->getRHS()->getType()->isPointerType()) { |
| // Degenerate case of (ptr -= ptr) allowed by GCC implicit cast |
| // extension, the conversion from the pointer difference back to |
| // the LHS type is handled at the end. |
| assert(E->getOpcode() == BinaryOperator::SubAssign && |
| "Invalid compound assignment operator on pointer type."); |
| RComputeTy = E->getLHS()->getType(); |
| ResultTy = CGF.getContext().getPointerDiffType(); |
| } else { |
| RComputeTy = E->getRHS()->getType(); |
| ResultTy = LComputeTy; |
| } |
| } else if (E->getRHS()->getType()->isPointerType()) { |
| // Degenerate case of (int += ptr) allowed by GCC implicit cast |
| // extension. |
| assert(E->getOpcode() == BinaryOperator::AddAssign && |
| "Invalid compound assignment operator on pointer type."); |
| LComputeTy = E->getLHS()->getType(); |
| RComputeTy = E->getRHS()->getType(); |
| ResultTy = RComputeTy; |
| } else { |
| LComputeTy = RComputeTy = ResultTy = ComputeType; |
| } |
| |
| // Convert the LHS/RHS values to the computation type. |
| OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, LComputeTy); |
| OpInfo.RHS = EmitScalarConversion(OpInfo.RHS, RHSTy, RComputeTy); |
| OpInfo.Ty = ResultTy; |
| OpInfo.E = E; |
| |
| // Expand the binary operator. |
| Value *Result = (this->*Func)(OpInfo); |
| |
| // Convert the result back to the LHS type. |
| Result = EmitScalarConversion(Result, ResultTy, LHSTy); |
| |
| // Store the result value into the LHS lvalue. Bit-fields are |
| // handled specially because the result is altered by the store. |
| if (LHSLV.isBitfield()) |
| CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy, |
| &Result); |
| else |
| CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); |
| |
| return Result; |
| } |
| |
| |
| Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { |
| if (Ops.LHS->getType()->isFPOrFPVector()) |
| return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); |
| else if (Ops.Ty->isUnsignedIntegerType()) |
| return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); |
| else |
| return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); |
| } |
| |
| Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { |
| // Rem in C can't be a floating point type: C99 6.5.5p2. |
| if (Ops.Ty->isUnsignedIntegerType()) |
| return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); |
| else |
| return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); |
| } |
| |
| |
| Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { |
| if (!Ops.Ty->isPointerType()) |
| return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); |
| |
| // FIXME: What about a pointer to a VLA? |
| Value *Ptr, *Idx; |
| Expr *IdxExp; |
| if (isa<llvm::PointerType>(Ops.LHS->getType())) { // pointer + int |
| Ptr = Ops.LHS; |
| Idx = Ops.RHS; |
| IdxExp = Ops.E->getRHS(); |
| } else { // int + pointer |
| Ptr = Ops.RHS; |
| Idx = Ops.LHS; |
| IdxExp = Ops.E->getLHS(); |
| } |
| |
| unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); |
| if (Width < CGF.LLVMPointerWidth) { |
| // Zero or sign extend the pointer value based on whether the index is |
| // signed or not. |
| const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); |
| if (IdxExp->getType()->isSignedIntegerType()) |
| Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); |
| else |
| Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); |
| } |
| |
| return Builder.CreateGEP(Ptr, Idx, "add.ptr"); |
| } |
| |
| Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { |
| if (!isa<llvm::PointerType>(Ops.LHS->getType())) |
| return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); |
| |
| if (!isa<llvm::PointerType>(Ops.RHS->getType())) { |
| // pointer - int |
| Value *Idx = Ops.RHS; |
| unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); |
| if (Width < CGF.LLVMPointerWidth) { |
| // Zero or sign extend the pointer value based on whether the index is |
| // signed or not. |
| const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); |
| if (Ops.E->getRHS()->getType()->isSignedIntegerType()) |
| Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); |
| else |
| Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); |
| } |
| Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); |
| |
| // FIXME: The pointer could point to a VLA. |
| // The GNU void* - int case is automatically handled here because |
| // our LLVM type for void* is i8*. |
| return Builder.CreateGEP(Ops.LHS, Idx, "sub.ptr"); |
| } else { |
| // pointer - pointer |
| Value *LHS = Ops.LHS; |
| Value *RHS = Ops.RHS; |
| |
| const QualType LHSType = Ops.E->getLHS()->getType(); |
| const QualType LHSElementType = LHSType->getAsPointerType()->getPointeeType(); |
| uint64_t ElementSize; |
| |
| // Handle GCC extension for pointer arithmetic on void* types. |
| if (LHSElementType->isVoidType()) { |
| ElementSize = 1; |
| } else { |
| ElementSize = CGF.getContext().getTypeSize(LHSElementType) / 8; |
| } |
| |
| const llvm::Type *ResultType = ConvertType(Ops.Ty); |
| LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); |
| RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); |
| Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); |
| |
| // HACK: LLVM doesn't have an divide instruction that 'knows' there is no |
| // remainder. As such, we handle common power-of-two cases here to generate |
| // better code. See PR2247. |
| if (llvm::isPowerOf2_64(ElementSize)) { |
| Value *ShAmt = |
| llvm::ConstantInt::get(ResultType, llvm::Log2_64(ElementSize)); |
| return Builder.CreateAShr(BytesBetween, ShAmt, "sub.ptr.shr"); |
| } |
| |
| // Otherwise, do a full sdiv. |
| Value *BytesPerElt = llvm::ConstantInt::get(ResultType, ElementSize); |
| return Builder.CreateSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); |
| } |
| } |
| |
| Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { |
| // LLVM requires the LHS and RHS to be the same type: promote or truncate the |
| // RHS to the same size as the LHS. |
| Value *RHS = Ops.RHS; |
| if (Ops.LHS->getType() != RHS->getType()) |
| RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); |
| |
| return Builder.CreateShl(Ops.LHS, RHS, "shl"); |
| } |
| |
| Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { |
| // LLVM requires the LHS and RHS to be the same type: promote or truncate the |
| // RHS to the same size as the LHS. |
| Value *RHS = Ops.RHS; |
| if (Ops.LHS->getType() != RHS->getType()) |
| RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); |
| |
| if (Ops.Ty->isUnsignedIntegerType()) |
| return Builder.CreateLShr(Ops.LHS, RHS, "shr"); |
| return Builder.CreateAShr(Ops.LHS, RHS, "shr"); |
| } |
| |
| Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, |
| unsigned SICmpOpc, unsigned FCmpOpc) { |
| Value *Result; |
| QualType LHSTy = E->getLHS()->getType(); |
| if (!LHSTy->isAnyComplexType() && !LHSTy->isVectorType()) { |
| Value *LHS = Visit(E->getLHS()); |
| Value *RHS = Visit(E->getRHS()); |
| |
| if (LHS->getType()->isFloatingPoint()) { |
| Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, |
| LHS, RHS, "cmp"); |
| } else if (LHSTy->isSignedIntegerType()) { |
| Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, |
| LHS, RHS, "cmp"); |
| } else { |
| // Unsigned integers and pointers. |
| Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, |
| LHS, RHS, "cmp"); |
| } |
| } else if (LHSTy->isVectorType()) { |
| Value *LHS = Visit(E->getLHS()); |
| Value *RHS = Visit(E->getRHS()); |
| |
| if (LHS->getType()->isFPOrFPVector()) { |
| Result = Builder.CreateVFCmp((llvm::CmpInst::Predicate)FCmpOpc, |
| LHS, RHS, "cmp"); |
| } else if (LHSTy->isUnsignedIntegerType()) { |
| Result = Builder.CreateVICmp((llvm::CmpInst::Predicate)UICmpOpc, |
| LHS, RHS, "cmp"); |
| } else { |
| // Signed integers and pointers. |
| Result = Builder.CreateVICmp((llvm::CmpInst::Predicate)SICmpOpc, |
| LHS, RHS, "cmp"); |
| } |
| return Result; |
| } else { |
| // Complex Comparison: can only be an equality comparison. |
| CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); |
| CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); |
| |
| QualType CETy = LHSTy->getAsComplexType()->getElementType(); |
| |
| Value *ResultR, *ResultI; |
| if (CETy->isRealFloatingType()) { |
| ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, |
| LHS.first, RHS.first, "cmp.r"); |
| ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, |
| LHS.second, RHS.second, "cmp.i"); |
| } else { |
| // Complex comparisons can only be equality comparisons. As such, signed |
| // and unsigned opcodes are the same. |
| ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, |
| LHS.first, RHS.first, "cmp.r"); |
| ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, |
| LHS.second, RHS.second, "cmp.i"); |
| } |
| |
| if (E->getOpcode() == BinaryOperator::EQ) { |
| Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); |
| } else { |
| assert(E->getOpcode() == BinaryOperator::NE && |
| "Complex comparison other than == or != ?"); |
| Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); |
| } |
| } |
| |
| // ZExt result to int. |
| return Builder.CreateZExt(Result, CGF.LLVMIntTy, "cmp.ext"); |
| } |
| |
| Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { |
| LValue LHS = EmitLValue(E->getLHS()); |
| Value *RHS = Visit(E->getRHS()); |
| |
| // Store the value into the LHS. Bit-fields are handled specially |
| // because the result is altered by the store. |
| // FIXME: Volatility! |
| if (LHS.isBitfield()) |
| CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(), |
| &RHS); |
| else |
| CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); |
| |
| // Return the RHS. |
| return RHS; |
| } |
| |
| Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { |
| // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. |
| // If we have 1 && X, just emit X without inserting the control flow. |
| if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { |
| if (Cond == 1) { // If we have 1 && X, just emit X. |
| Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); |
| // ZExt result to int. |
| return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "land.ext"); |
| } |
| |
| // 0 && RHS: If it is safe, just elide the RHS, and return 0. |
| if (!CGF.ContainsLabel(E->getRHS())) |
| return llvm::Constant::getNullValue(CGF.LLVMIntTy); |
| } |
| |
| llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); |
| llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); |
| |
| // Branch on the LHS first. If it is false, go to the failure (cont) block. |
| CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); |
| |
| // Any edges into the ContBlock are now from an (indeterminate number of) |
| // edges from this first condition. All of these values will be false. Start |
| // setting up the PHI node in the Cont Block for this. |
| llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); |
| PN->reserveOperandSpace(2); // Normal case, two inputs. |
| for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); |
| PI != PE; ++PI) |
| PN->addIncoming(llvm::ConstantInt::getFalse(), *PI); |
| |
| CGF.EmitBlock(RHSBlock); |
| Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); |
| |
| // Reaquire the RHS block, as there may be subblocks inserted. |
| RHSBlock = Builder.GetInsertBlock(); |
| |
| // Emit an unconditional branch from this block to ContBlock. Insert an entry |
| // into the phi node for the edge with the value of RHSCond. |
| CGF.EmitBlock(ContBlock); |
| PN->addIncoming(RHSCond, RHSBlock); |
| |
| // ZExt result to int. |
| return Builder.CreateZExt(PN, CGF.LLVMIntTy, "land.ext"); |
| } |
| |
| Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { |
| // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. |
| // If we have 0 || X, just emit X without inserting the control flow. |
| if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { |
| if (Cond == -1) { // If we have 0 || X, just emit X. |
| Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); |
| // ZExt result to int. |
| return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "lor.ext"); |
| } |
| |
| // 1 || RHS: If it is safe, just elide the RHS, and return 0. |
| if (!CGF.ContainsLabel(E->getRHS())) |
| return llvm::Constant::getNullValue(CGF.LLVMIntTy); |
| } |
| |
| llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); |
| llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); |
| |
| // Branch on the LHS first. If it is true, go to the success (cont) block. |
| CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); |
| |
| // Any edges into the ContBlock are now from an (indeterminate number of) |
| // edges from this first condition. All of these values will be true. Start |
| // setting up the PHI node in the Cont Block for this. |
| llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); |
| PN->reserveOperandSpace(2); // Normal case, two inputs. |
| for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); |
| PI != PE; ++PI) |
| PN->addIncoming(llvm::ConstantInt::getTrue(), *PI); |
| |
| // Emit the RHS condition as a bool value. |
| CGF.EmitBlock(RHSBlock); |
| Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); |
| |
| // Reaquire the RHS block, as there may be subblocks inserted. |
| RHSBlock = Builder.GetInsertBlock(); |
| |
| // Emit an unconditional branch from this block to ContBlock. Insert an entry |
| // into the phi node for the edge with the value of RHSCond. |
| CGF.EmitBlock(ContBlock); |
| PN->addIncoming(RHSCond, RHSBlock); |
| |
| // ZExt result to int. |
| return Builder.CreateZExt(PN, CGF.LLVMIntTy, "lor.ext"); |
| } |
| |
| Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { |
| CGF.EmitStmt(E->getLHS()); |
| CGF.EnsureInsertPoint(); |
| return Visit(E->getRHS()); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Other Operators |
| //===----------------------------------------------------------------------===// |
| |
| /// isCheapEnoughToEvaluateUnconditionally - Return true if the specified |
| /// expression is cheap enough and side-effect-free enough to evaluate |
| /// unconditionally instead of conditionally. This is used to convert control |
| /// flow into selects in some cases. |
| static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E) { |
| if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) |
| return isCheapEnoughToEvaluateUnconditionally(PE->getSubExpr()); |
| |
| // TODO: Allow anything we can constant fold to an integer or fp constant. |
| if (isa<IntegerLiteral>(E) || isa<CharacterLiteral>(E) || |
| isa<FloatingLiteral>(E)) |
| return true; |
| |
| // Non-volatile automatic variables too, to get "cond ? X : Y" where |
| // X and Y are local variables. |
| if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) |
| if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) |
| if (VD->hasLocalStorage() && !VD->getType().isVolatileQualified()) |
| return true; |
| |
| return false; |
| } |
| |
| |
| Value *ScalarExprEmitter:: |
| VisitConditionalOperator(const ConditionalOperator *E) { |
| // If the condition constant folds and can be elided, try to avoid emitting |
| // the condition and the dead arm. |
| if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getCond())){ |
| Expr *Live = E->getLHS(), *Dead = E->getRHS(); |
| if (Cond == -1) |
| std::swap(Live, Dead); |
| |
| // If the dead side doesn't have labels we need, and if the Live side isn't |
| // the gnu missing ?: extension (which we could handle, but don't bother |
| // to), just emit the Live part. |
| if ((!Dead || !CGF.ContainsLabel(Dead)) && // No labels in dead part |
| Live) // Live part isn't missing. |
| return Visit(Live); |
| } |
| |
| |
| // If this is a really simple expression (like x ? 4 : 5), emit this as a |
| // select instead of as control flow. We can only do this if it is cheap and |
| // safe to evaluate the LHS and RHS unconditionally. |
| if (E->getLHS() && isCheapEnoughToEvaluateUnconditionally(E->getLHS()) && |
| isCheapEnoughToEvaluateUnconditionally(E->getRHS())) { |
| llvm::Value *CondV = CGF.EvaluateExprAsBool(E->getCond()); |
| llvm::Value *LHS = Visit(E->getLHS()); |
| llvm::Value *RHS = Visit(E->getRHS()); |
| return Builder.CreateSelect(CondV, LHS, RHS, "cond"); |
| } |
| |
| |
| llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); |
| llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); |
| llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); |
| Value *CondVal = 0; |
| |
| // If we have the GNU missing condition extension, evaluate the conditional |
| // and then convert it to bool the hard way. We do this explicitly |
| // because we need the unconverted value for the missing middle value of |
| // the ?:. |
| if (E->getLHS() == 0) { |
| CondVal = CGF.EmitScalarExpr(E->getCond()); |
| Value *CondBoolVal = |
| CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), |
| CGF.getContext().BoolTy); |
| Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); |
| } else { |
| // Otherwise, just use EmitBranchOnBoolExpr to get small and simple code for |
| // the branch on bool. |
| CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock); |
| } |
| |
| CGF.EmitBlock(LHSBlock); |
| |
| // Handle the GNU extension for missing LHS. |
| Value *LHS; |
| if (E->getLHS()) |
| LHS = Visit(E->getLHS()); |
| else // Perform promotions, to handle cases like "short ?: int" |
| LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType()); |
| |
| LHSBlock = Builder.GetInsertBlock(); |
| CGF.EmitBranch(ContBlock); |
| |
| CGF.EmitBlock(RHSBlock); |
| |
| Value *RHS = Visit(E->getRHS()); |
| RHSBlock = Builder.GetInsertBlock(); |
| CGF.EmitBranch(ContBlock); |
| |
| CGF.EmitBlock(ContBlock); |
| |
| if (!LHS || !RHS) { |
| assert(E->getType()->isVoidType() && "Non-void value should have a value"); |
| return 0; |
| } |
| |
| // Create a PHI node for the real part. |
| llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); |
| PN->reserveOperandSpace(2); |
| PN->addIncoming(LHS, LHSBlock); |
| PN->addIncoming(RHS, RHSBlock); |
| return PN; |
| } |
| |
| Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { |
| // Emit the LHS or RHS as appropriate. |
| return |
| Visit(E->isConditionTrue(CGF.getContext()) ? E->getLHS() : E->getRHS()); |
| } |
| |
| Value *ScalarExprEmitter::VisitOverloadExpr(OverloadExpr *E) { |
| return CGF.EmitCallExpr(E->getFn(), E->arg_begin(), |
| E->arg_end(CGF.getContext())).getScalarVal(); |
| } |
| |
| Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { |
| llvm::Value *ArgValue = EmitLValue(VE->getSubExpr()).getAddress(); |
| |
| llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); |
| |
| // If EmitVAArg fails, we fall back to the LLVM instruction. |
| if (!ArgPtr) |
| return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); |
| |
| // FIXME: volatile? |
| return Builder.CreateLoad(ArgPtr); |
| } |
| |
| Value *ScalarExprEmitter::VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { |
| std::string str; |
| CGF.getContext().getObjCEncodingForType(E->getEncodedType(), str); |
| |
| llvm::Constant *C = llvm::ConstantArray::get(str); |
| C = new llvm::GlobalVariable(C->getType(), true, |
| llvm::GlobalValue::InternalLinkage, |
| C, ".str", &CGF.CGM.getModule()); |
| llvm::Constant *Zero = llvm::Constant::getNullValue(llvm::Type::Int32Ty); |
| llvm::Constant *Zeros[] = { Zero, Zero }; |
| C = llvm::ConstantExpr::getGetElementPtr(C, Zeros, 2); |
| |
| return C; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Entry Point into this File |
| //===----------------------------------------------------------------------===// |
| |
| /// EmitComplexExpr - Emit the computation of the specified expression of |
| /// complex type, ignoring the result. |
| Value *CodeGenFunction::EmitScalarExpr(const Expr *E) { |
| assert(E && !hasAggregateLLVMType(E->getType()) && |
| "Invalid scalar expression to emit"); |
| |
| return ScalarExprEmitter(*this).Visit(const_cast<Expr*>(E)); |
| } |
| |
| /// EmitScalarConversion - Emit a conversion from the specified type to the |
| /// specified destination type, both of which are LLVM scalar types. |
| Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, |
| QualType DstTy) { |
| assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && |
| "Invalid scalar expression to emit"); |
| return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); |
| } |
| |
| /// EmitComplexToScalarConversion - Emit a conversion from the specified |
| /// complex type to the specified destination type, where the destination |
| /// type is an LLVM scalar type. |
| Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, |
| QualType SrcTy, |
| QualType DstTy) { |
| assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && |
| "Invalid complex -> scalar conversion"); |
| return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, |
| DstTy); |
| } |
| |
| Value *CodeGenFunction::EmitShuffleVector(Value* V1, Value *V2, ...) { |
| assert(V1->getType() == V2->getType() && |
| "Vector operands must be of the same type"); |
| unsigned NumElements = |
| cast<llvm::VectorType>(V1->getType())->getNumElements(); |
| |
| va_list va; |
| va_start(va, V2); |
| |
| llvm::SmallVector<llvm::Constant*, 16> Args; |
| for (unsigned i = 0; i < NumElements; i++) { |
| int n = va_arg(va, int); |
| assert(n >= 0 && n < (int)NumElements * 2 && |
| "Vector shuffle index out of bounds!"); |
| Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, n)); |
| } |
| |
| const char *Name = va_arg(va, const char *); |
| va_end(va); |
| |
| llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); |
| |
| return Builder.CreateShuffleVector(V1, V2, Mask, Name); |
| } |
| |
| llvm::Value *CodeGenFunction::EmitVector(llvm::Value * const *Vals, |
| unsigned NumVals, bool isSplat) { |
| llvm::Value *Vec |
| = llvm::UndefValue::get(llvm::VectorType::get(Vals[0]->getType(), NumVals)); |
| |
| for (unsigned i = 0, e = NumVals; i != e; ++i) { |
| llvm::Value *Val = isSplat ? Vals[0] : Vals[i]; |
| llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); |
| Vec = Builder.CreateInsertElement(Vec, Val, Idx, "tmp"); |
| } |
| |
| return Vec; |
| } |