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//===--- 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 "CGCXXABI.h"
#include "CGDebugInfo.h"
#include "CGObjCRuntime.h"
#include "CodeGenModule.h"
#include "TargetInfo.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/RecordLayout.h"
#include "clang/AST/StmtVisitor.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Frontend/CodeGenOptions.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/Module.h"
#include <cstdarg>
using namespace clang;
using namespace CodeGen;
using llvm::Value;
//===----------------------------------------------------------------------===//
// Scalar Expression Emitter
//===----------------------------------------------------------------------===//
namespace {
struct BinOpInfo {
Value *LHS;
Value *RHS;
QualType Ty; // Computation Type.
BinaryOperator::Opcode Opcode; // Opcode of BinOp to perform
bool FPContractable;
const Expr *E; // Entire expr, for error unsupported. May not be binop.
};
static bool MustVisitNullValue(const Expr *E) {
// If a null pointer expression's type is the C++0x nullptr_t, then
// it's not necessarily a simple constant and it must be evaluated
// for its potential side effects.
return E->getType()->isNullPtrType();
}
class ScalarExprEmitter
: public StmtVisitor<ScalarExprEmitter, Value*> {
CodeGenFunction &CGF;
CGBuilderTy &Builder;
bool IgnoreResultAssign;
llvm::LLVMContext &VMContext;
public:
ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false)
: CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira),
VMContext(cgf.getLLVMContext()) {
}
//===--------------------------------------------------------------------===//
// Utilities
//===--------------------------------------------------------------------===//
bool TestAndClearIgnoreResultAssign() {
bool I = IgnoreResultAssign;
IgnoreResultAssign = false;
return I;
}
llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); }
LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); }
LValue EmitCheckedLValue(const Expr *E, CodeGenFunction::TypeCheckKind TCK) {
return CGF.EmitCheckedLValue(E, TCK);
}
void EmitBinOpCheck(ArrayRef<std::pair<Value *, SanitizerMask>> Checks,
const BinOpInfo &Info);
Value *EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
return CGF.EmitLoadOfLValue(LV, Loc).getScalarVal();
}
void EmitLValueAlignmentAssumption(const Expr *E, Value *V) {
const AlignValueAttr *AVAttr = nullptr;
if (const auto *DRE = dyn_cast<DeclRefExpr>(E)) {
const ValueDecl *VD = DRE->getDecl();
if (VD->getType()->isReferenceType()) {
if (const auto *TTy =
dyn_cast<TypedefType>(VD->getType().getNonReferenceType()))
AVAttr = TTy->getDecl()->getAttr<AlignValueAttr>();
} else {
// Assumptions for function parameters are emitted at the start of the
// function, so there is no need to repeat that here.
if (isa<ParmVarDecl>(VD))
return;
AVAttr = VD->getAttr<AlignValueAttr>();
}
}
if (!AVAttr)
if (const auto *TTy =
dyn_cast<TypedefType>(E->getType()))
AVAttr = TTy->getDecl()->getAttr<AlignValueAttr>();
if (!AVAttr)
return;
Value *AlignmentValue = CGF.EmitScalarExpr(AVAttr->getAlignment());
llvm::ConstantInt *AlignmentCI = cast<llvm::ConstantInt>(AlignmentValue);
CGF.EmitAlignmentAssumption(V, AlignmentCI->getZExtValue());
}
/// 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) {
Value *V = EmitLoadOfLValue(EmitCheckedLValue(E, CodeGenFunction::TCK_Load),
E->getExprLoc());
EmitLValueAlignmentAssumption(E, V);
return V;
}
/// EmitConversionToBool - Convert the specified expression value to a
/// boolean (i1) truth value. This is equivalent to "Val != 0".
Value *EmitConversionToBool(Value *Src, QualType DstTy);
/// Emit a check that a conversion to or from a floating-point type does not
/// overflow.
void EmitFloatConversionCheck(Value *OrigSrc, QualType OrigSrcType,
Value *Src, QualType SrcType, QualType DstType,
llvm::Type *DstTy, SourceLocation Loc);
/// 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,
SourceLocation Loc);
Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy,
SourceLocation Loc, bool TreatBooleanAsSigned);
/// 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,
SourceLocation Loc);
/// EmitNullValue - Emit a value that corresponds to null for the given type.
Value *EmitNullValue(QualType Ty);
/// EmitFloatToBoolConversion - Perform an FP to boolean conversion.
Value *EmitFloatToBoolConversion(Value *V) {
// Compare against 0.0 for fp scalars.
llvm::Value *Zero = llvm::Constant::getNullValue(V->getType());
return Builder.CreateFCmpUNE(V, Zero, "tobool");
}
/// EmitPointerToBoolConversion - Perform a pointer to boolean conversion.
Value *EmitPointerToBoolConversion(Value *V) {
Value *Zero = llvm::ConstantPointerNull::get(
cast<llvm::PointerType>(V->getType()));
return Builder.CreateICmpNE(V, Zero, "tobool");
}
Value *EmitIntToBoolConversion(Value *V) {
// 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>(V)) {
if (ZI->getOperand(0)->getType() == Builder.getInt1Ty()) {
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;
}
}
return Builder.CreateIsNotNull(V, "tobool");
}
//===--------------------------------------------------------------------===//
// Visitor Methods
//===--------------------------------------------------------------------===//
Value *Visit(Expr *E) {
ApplyDebugLocation DL(CGF, E);
return StmtVisitor<ScalarExprEmitter, Value*>::Visit(E);
}
Value *VisitStmt(Stmt *S) {
S->dump(CGF.getContext().getSourceManager());
llvm_unreachable("Stmt can't have complex result type!");
}
Value *VisitExpr(Expr *S);
Value *VisitParenExpr(ParenExpr *PE) {
return Visit(PE->getSubExpr());
}
Value *VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *E) {
return Visit(E->getReplacement());
}
Value *VisitGenericSelectionExpr(GenericSelectionExpr *GE) {
return Visit(GE->getResultExpr());
}
// Leaves.
Value *VisitIntegerLiteral(const IntegerLiteral *E) {
return Builder.getInt(E->getValue());
}
Value *VisitFloatingLiteral(const FloatingLiteral *E) {
return llvm::ConstantFP::get(VMContext, E->getValue());
}
Value *VisitCharacterLiteral(const CharacterLiteral *E) {
return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
}
Value *VisitObjCBoolLiteralExpr(const ObjCBoolLiteralExpr *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 *VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) {
return EmitNullValue(E->getType());
}
Value *VisitGNUNullExpr(const GNUNullExpr *E) {
return EmitNullValue(E->getType());
}
Value *VisitOffsetOfExpr(OffsetOfExpr *E);
Value *VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E);
Value *VisitAddrLabelExpr(const AddrLabelExpr *E) {
llvm::Value *V = CGF.GetAddrOfLabel(E->getLabel());
return Builder.CreateBitCast(V, ConvertType(E->getType()));
}
Value *VisitSizeOfPackExpr(SizeOfPackExpr *E) {
return llvm::ConstantInt::get(ConvertType(E->getType()),E->getPackLength());
}
Value *VisitPseudoObjectExpr(PseudoObjectExpr *E) {
return CGF.EmitPseudoObjectRValue(E).getScalarVal();
}
Value *VisitOpaqueValueExpr(OpaqueValueExpr *E) {
if (E->isGLValue())
return EmitLoadOfLValue(CGF.getOpaqueLValueMapping(E), E->getExprLoc());
// Otherwise, assume the mapping is the scalar directly.
return CGF.getOpaqueRValueMapping(E).getScalarVal();
}
// l-values.
Value *VisitDeclRefExpr(DeclRefExpr *E) {
if (CodeGenFunction::ConstantEmission result = CGF.tryEmitAsConstant(E)) {
if (result.isReference())
return EmitLoadOfLValue(result.getReferenceLValue(CGF, E),
E->getExprLoc());
return result.getValue();
}
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 *VisitObjCMessageExpr(ObjCMessageExpr *E) {
if (E->getMethodDecl() &&
E->getMethodDecl()->getReturnType()->isReferenceType())
return EmitLoadOfLValue(E);
return CGF.EmitObjCMessageExpr(E).getScalarVal();
}
Value *VisitObjCIsaExpr(ObjCIsaExpr *E) {
LValue LV = CGF.EmitObjCIsaExpr(E);
Value *V = CGF.EmitLoadOfLValue(LV, E->getExprLoc()).getScalarVal();
return V;
}
Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E);
Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E);
Value *VisitConvertVectorExpr(ConvertVectorExpr *E);
Value *VisitMemberExpr(MemberExpr *E);
Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); }
Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
return EmitLoadOfLValue(E);
}
Value *VisitInitListExpr(InitListExpr *E);
Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
return EmitNullValue(E->getType());
}
Value *VisitExplicitCastExpr(ExplicitCastExpr *E) {
CGF.CGM.EmitExplicitCastExprType(E, &CGF);
return VisitCastExpr(E);
}
Value *VisitCastExpr(CastExpr *E);
Value *VisitCallExpr(const CallExpr *E) {
if (E->getCallReturnType(CGF.getContext())->isReferenceType())
return EmitLoadOfLValue(E);
Value *V = CGF.EmitCallExpr(E).getScalarVal();
EmitLValueAlignmentAssumption(E, V);
return V;
}
Value *VisitStmtExpr(const StmtExpr *E);
// Unary Operators.
Value *VisitUnaryPostDec(const UnaryOperator *E) {
LValue LV = EmitLValue(E->getSubExpr());
return EmitScalarPrePostIncDec(E, LV, false, false);
}
Value *VisitUnaryPostInc(const UnaryOperator *E) {
LValue LV = EmitLValue(E->getSubExpr());
return EmitScalarPrePostIncDec(E, LV, true, false);
}
Value *VisitUnaryPreDec(const UnaryOperator *E) {
LValue LV = EmitLValue(E->getSubExpr());
return EmitScalarPrePostIncDec(E, LV, false, true);
}
Value *VisitUnaryPreInc(const UnaryOperator *E) {
LValue LV = EmitLValue(E->getSubExpr());
return EmitScalarPrePostIncDec(E, LV, true, true);
}
llvm::Value *EmitIncDecConsiderOverflowBehavior(const UnaryOperator *E,
llvm::Value *InVal,
bool IsInc);
llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
bool isInc, bool isPre);
Value *VisitUnaryAddrOf(const UnaryOperator *E) {
if (isa<MemberPointerType>(E->getType())) // never sugared
return CGF.CGM.getMemberPointerConstant(E);
return EmitLValue(E->getSubExpr()).getPointer();
}
Value *VisitUnaryDeref(const UnaryOperator *E) {
if (E->getType()->isVoidType())
return Visit(E->getSubExpr()); // the actual value should be unused
return EmitLoadOfLValue(E);
}
Value *VisitUnaryPlus(const UnaryOperator *E) {
// This differs from gcc, though, most likely due to a bug in gcc.
TestAndClearIgnoreResultAssign();
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());
}
// C++
Value *VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E) {
return EmitLoadOfLValue(E);
}
Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
return Visit(DAE->getExpr());
}
Value *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) {
CodeGenFunction::CXXDefaultInitExprScope Scope(CGF);
return Visit(DIE->getExpr());
}
Value *VisitCXXThisExpr(CXXThisExpr *TE) {
return CGF.LoadCXXThis();
}
Value *VisitExprWithCleanups(ExprWithCleanups *E) {
CGF.enterFullExpression(E);
CodeGenFunction::RunCleanupsScope Scope(CGF);
return Visit(E->getSubExpr());
}
Value *VisitCXXNewExpr(const CXXNewExpr *E) {
return CGF.EmitCXXNewExpr(E);
}
Value *VisitCXXDeleteExpr(const CXXDeleteExpr *E) {
CGF.EmitCXXDeleteExpr(E);
return nullptr;
}
Value *VisitTypeTraitExpr(const TypeTraitExpr *E) {
return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
}
Value *VisitArrayTypeTraitExpr(const ArrayTypeTraitExpr *E) {
return llvm::ConstantInt::get(Builder.getInt32Ty(), E->getValue());
}
Value *VisitExpressionTraitExpr(const ExpressionTraitExpr *E) {
return llvm::ConstantInt::get(Builder.getInt1Ty(), E->getValue());
}
Value *VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) {
// 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.
CGF.EmitScalarExpr(E->getBase());
return nullptr;
}
Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) {
return EmitNullValue(E->getType());
}
Value *VisitCXXThrowExpr(const CXXThrowExpr *E) {
CGF.EmitCXXThrowExpr(E);
return nullptr;
}
Value *VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) {
return Builder.getInt1(E->getValue());
}
// Binary Operators.
Value *EmitMul(const BinOpInfo &Ops) {
if (Ops.Ty->isSignedIntegerOrEnumerationType()) {
switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
case LangOptions::SOB_Defined:
return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul");
case LangOptions::SOB_Undefined:
if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
return Builder.CreateNSWMul(Ops.LHS, Ops.RHS, "mul");
// Fall through.
case LangOptions::SOB_Trapping:
return EmitOverflowCheckedBinOp(Ops);
}
}
if (Ops.Ty->isUnsignedIntegerType() &&
CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow))
return EmitOverflowCheckedBinOp(Ops);
if (Ops.LHS->getType()->isFPOrFPVectorTy())
return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul");
return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul");
}
/// Create a binary op that checks for overflow.
/// Currently only supports +, - and *.
Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops);
// Check for undefined division and modulus behaviors.
void EmitUndefinedBehaviorIntegerDivAndRemCheck(const BinOpInfo &Ops,
llvm::Value *Zero,bool isDiv);
// Common helper for getting how wide LHS of shift is.
static Value *GetWidthMinusOneValue(Value* LHS,Value* RHS);
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);
LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E,
Value *(ScalarExprEmitter::*F)(const BinOpInfo &),
Value *&Result);
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, llvm::CmpInst::Predicate UICmpOpc,
llvm::CmpInst::Predicate SICmpOpc,
llvm::CmpInst::Predicate 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);
Value *VisitBinPtrMemD(const Expr *E) { return EmitLoadOfLValue(E); }
Value *VisitBinPtrMemI(const Expr *E) { return EmitLoadOfLValue(E); }
// Other Operators.
Value *VisitBlockExpr(const BlockExpr *BE);
Value *VisitAbstractConditionalOperator(const AbstractConditionalOperator *);
Value *VisitChooseExpr(ChooseExpr *CE);
Value *VisitVAArgExpr(VAArgExpr *VE);
Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) {
return CGF.EmitObjCStringLiteral(E);
}
Value *VisitObjCBoxedExpr(ObjCBoxedExpr *E) {
return CGF.EmitObjCBoxedExpr(E);
}
Value *VisitObjCArrayLiteral(ObjCArrayLiteral *E) {
return CGF.EmitObjCArrayLiteral(E);
}
Value *VisitObjCDictionaryLiteral(ObjCDictionaryLiteral *E) {
return CGF.EmitObjCDictionaryLiteral(E);
}
Value *VisitAsTypeExpr(AsTypeExpr *CE);
Value *VisitAtomicExpr(AtomicExpr *AE);
};
} // 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())
return EmitFloatToBoolConversion(Src);
if (const MemberPointerType *MPT = dyn_cast<MemberPointerType>(SrcType))
return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, Src, MPT);
assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) &&
"Unknown scalar type to convert");
if (isa<llvm::IntegerType>(Src->getType()))
return EmitIntToBoolConversion(Src);
assert(isa<llvm::PointerType>(Src->getType()));
return EmitPointerToBoolConversion(Src);
}
void ScalarExprEmitter::EmitFloatConversionCheck(
Value *OrigSrc, QualType OrigSrcType, Value *Src, QualType SrcType,
QualType DstType, llvm::Type *DstTy, SourceLocation Loc) {
CodeGenFunction::SanitizerScope SanScope(&CGF);
using llvm::APFloat;
using llvm::APSInt;
llvm::Type *SrcTy = Src->getType();
llvm::Value *Check = nullptr;
if (llvm::IntegerType *IntTy = dyn_cast<llvm::IntegerType>(SrcTy)) {
// Integer to floating-point. This can fail for unsigned short -> __half
// or unsigned __int128 -> float.
assert(DstType->isFloatingType());
bool SrcIsUnsigned = OrigSrcType->isUnsignedIntegerOrEnumerationType();
APFloat LargestFloat =
APFloat::getLargest(CGF.getContext().getFloatTypeSemantics(DstType));
APSInt LargestInt(IntTy->getBitWidth(), SrcIsUnsigned);
bool IsExact;
if (LargestFloat.convertToInteger(LargestInt, APFloat::rmTowardZero,
&IsExact) != APFloat::opOK)
// The range of representable values of this floating point type includes
// all values of this integer type. Don't need an overflow check.
return;
llvm::Value *Max = llvm::ConstantInt::get(VMContext, LargestInt);
if (SrcIsUnsigned)
Check = Builder.CreateICmpULE(Src, Max);
else {
llvm::Value *Min = llvm::ConstantInt::get(VMContext, -LargestInt);
llvm::Value *GE = Builder.CreateICmpSGE(Src, Min);
llvm::Value *LE = Builder.CreateICmpSLE(Src, Max);
Check = Builder.CreateAnd(GE, LE);
}
} else {
const llvm::fltSemantics &SrcSema =
CGF.getContext().getFloatTypeSemantics(OrigSrcType);
if (isa<llvm::IntegerType>(DstTy)) {
// Floating-point to integer. This has undefined behavior if the source is
// +-Inf, NaN, or doesn't fit into the destination type (after truncation
// to an integer).
unsigned Width = CGF.getContext().getIntWidth(DstType);
bool Unsigned = DstType->isUnsignedIntegerOrEnumerationType();
APSInt Min = APSInt::getMinValue(Width, Unsigned);
APFloat MinSrc(SrcSema, APFloat::uninitialized);
if (MinSrc.convertFromAPInt(Min, !Unsigned, APFloat::rmTowardZero) &
APFloat::opOverflow)
// Don't need an overflow check for lower bound. Just check for
// -Inf/NaN.
MinSrc = APFloat::getInf(SrcSema, true);
else
// Find the largest value which is too small to represent (before
// truncation toward zero).
MinSrc.subtract(APFloat(SrcSema, 1), APFloat::rmTowardNegative);
APSInt Max = APSInt::getMaxValue(Width, Unsigned);
APFloat MaxSrc(SrcSema, APFloat::uninitialized);
if (MaxSrc.convertFromAPInt(Max, !Unsigned, APFloat::rmTowardZero) &
APFloat::opOverflow)
// Don't need an overflow check for upper bound. Just check for
// +Inf/NaN.
MaxSrc = APFloat::getInf(SrcSema, false);
else
// Find the smallest value which is too large to represent (before
// truncation toward zero).
MaxSrc.add(APFloat(SrcSema, 1), APFloat::rmTowardPositive);
// If we're converting from __half, convert the range to float to match
// the type of src.
if (OrigSrcType->isHalfType()) {
const llvm::fltSemantics &Sema =
CGF.getContext().getFloatTypeSemantics(SrcType);
bool IsInexact;
MinSrc.convert(Sema, APFloat::rmTowardZero, &IsInexact);
MaxSrc.convert(Sema, APFloat::rmTowardZero, &IsInexact);
}
llvm::Value *GE =
Builder.CreateFCmpOGT(Src, llvm::ConstantFP::get(VMContext, MinSrc));
llvm::Value *LE =
Builder.CreateFCmpOLT(Src, llvm::ConstantFP::get(VMContext, MaxSrc));
Check = Builder.CreateAnd(GE, LE);
} else {
// FIXME: Maybe split this sanitizer out from float-cast-overflow.
//
// Floating-point to floating-point. This has undefined behavior if the
// source is not in the range of representable values of the destination
// type. The C and C++ standards are spectacularly unclear here. We
// diagnose finite out-of-range conversions, but allow infinities and NaNs
// to convert to the corresponding value in the smaller type.
//
// C11 Annex F gives all such conversions defined behavior for IEC 60559
// conforming implementations. Unfortunately, LLVM's fptrunc instruction
// does not.
// Converting from a lower rank to a higher rank can never have
// undefined behavior, since higher-rank types must have a superset
// of values of lower-rank types.
if (CGF.getContext().getFloatingTypeOrder(OrigSrcType, DstType) != 1)
return;
assert(!OrigSrcType->isHalfType() &&
"should not check conversion from __half, it has the lowest rank");
const llvm::fltSemantics &DstSema =
CGF.getContext().getFloatTypeSemantics(DstType);
APFloat MinBad = APFloat::getLargest(DstSema, false);
APFloat MaxBad = APFloat::getInf(DstSema, false);
bool IsInexact;
MinBad.convert(SrcSema, APFloat::rmTowardZero, &IsInexact);
MaxBad.convert(SrcSema, APFloat::rmTowardZero, &IsInexact);
Value *AbsSrc = CGF.EmitNounwindRuntimeCall(
CGF.CGM.getIntrinsic(llvm::Intrinsic::fabs, Src->getType()), Src);
llvm::Value *GE =
Builder.CreateFCmpOGT(AbsSrc, llvm::ConstantFP::get(VMContext, MinBad));
llvm::Value *LE =
Builder.CreateFCmpOLT(AbsSrc, llvm::ConstantFP::get(VMContext, MaxBad));
Check = Builder.CreateNot(Builder.CreateAnd(GE, LE));
}
}
llvm::Constant *StaticArgs[] = {CGF.EmitCheckSourceLocation(Loc),
CGF.EmitCheckTypeDescriptor(OrigSrcType),
CGF.EmitCheckTypeDescriptor(DstType)};
CGF.EmitCheck(std::make_pair(Check, SanitizerKind::FloatCastOverflow),
"float_cast_overflow", StaticArgs, OrigSrc);
}
/// 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,
SourceLocation Loc) {
return EmitScalarConversion(Src, SrcType, DstType, Loc, false);
}
Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType,
QualType DstType,
SourceLocation Loc,
bool TreatBooleanAsSigned) {
SrcType = CGF.getContext().getCanonicalType(SrcType);
DstType = CGF.getContext().getCanonicalType(DstType);
if (SrcType == DstType) return Src;
if (DstType->isVoidType()) return nullptr;
llvm::Value *OrigSrc = Src;
QualType OrigSrcType = SrcType;
llvm::Type *SrcTy = Src->getType();
// Handle conversions to bool first, they are special: comparisons against 0.
if (DstType->isBooleanType())
return EmitConversionToBool(Src, SrcType);
llvm::Type *DstTy = ConvertType(DstType);
// Cast from half through float if half isn't a native type.
if (SrcType->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
// Cast to FP using the intrinsic if the half type itself isn't supported.
if (DstTy->isFloatingPointTy()) {
if (!CGF.getContext().getLangOpts().HalfArgsAndReturns)
return Builder.CreateCall(
CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16, DstTy),
Src);
} else {
// Cast to other types through float, using either the intrinsic or FPExt,
// depending on whether the half type itself is supported
// (as opposed to operations on half, available with NativeHalfType).
if (!CGF.getContext().getLangOpts().HalfArgsAndReturns) {
Src = Builder.CreateCall(
CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16,
CGF.CGM.FloatTy),
Src);
} else {
Src = Builder.CreateFPExt(Src, CGF.CGM.FloatTy, "conv");
}
SrcType = CGF.getContext().FloatTy;
SrcTy = CGF.FloatTy;
}
}
// Ignore conversions like int -> uint.
if (SrcTy == 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>(SrcTy))
return Builder.CreateBitCast(Src, DstTy, "conv");
assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?");
// First, convert to the correct width so that we control the kind of
// extension.
llvm::Type *MiddleTy = CGF.IntPtrTy;
bool InputSigned = SrcType->isSignedIntegerOrEnumerationType();
llvm::Value* IntResult =
Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv");
// Then, cast to pointer.
return Builder.CreateIntToPtr(IntResult, DstTy, "conv");
}
if (isa<llvm::PointerType>(SrcTy)) {
// 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() && !SrcType->isVectorType()) {
// Sema should add casts to make sure that the source expression's type is
// the same as the vector's element type (sans qualifiers)
assert(DstType->castAs<ExtVectorType>()->getElementType().getTypePtr() ==
SrcType.getTypePtr() &&
"Splatted expr doesn't match with vector element type?");
// Splat the element across to all elements
unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements();
return Builder.CreateVectorSplat(NumElements, Src, "splat");
}
// Allow bitcast from vector to integer/fp of the same size.
if (isa<llvm::VectorType>(SrcTy) ||
isa<llvm::VectorType>(DstTy))
return Builder.CreateBitCast(Src, DstTy, "conv");
// Finally, we have the arithmetic types: real int/float.
Value *Res = nullptr;
llvm::Type *ResTy = DstTy;
// An overflowing conversion has undefined behavior if either the source type
// or the destination type is a floating-point type.
if (CGF.SanOpts.has(SanitizerKind::FloatCastOverflow) &&
(OrigSrcType->isFloatingType() || DstType->isFloatingType()))
EmitFloatConversionCheck(OrigSrc, OrigSrcType, Src, SrcType, DstType, DstTy,
Loc);
// Cast to half through float if half isn't a native type.
if (DstType->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
// Make sure we cast in a single step if from another FP type.
if (SrcTy->isFloatingPointTy()) {
// Use the intrinsic if the half type itself isn't supported
// (as opposed to operations on half, available with NativeHalfType).
if (!CGF.getContext().getLangOpts().HalfArgsAndReturns)
return Builder.CreateCall(
CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16, SrcTy), Src);
// If the half type is supported, just use an fptrunc.
return Builder.CreateFPTrunc(Src, DstTy);
}
DstTy = CGF.FloatTy;
}
if (isa<llvm::IntegerType>(SrcTy)) {
bool InputSigned = SrcType->isSignedIntegerOrEnumerationType();
if (SrcType->isBooleanType() && TreatBooleanAsSigned) {
InputSigned = true;
}
if (isa<llvm::IntegerType>(DstTy))
Res = Builder.CreateIntCast(Src, DstTy, InputSigned, "conv");
else if (InputSigned)
Res = Builder.CreateSIToFP(Src, DstTy, "conv");
else
Res = Builder.CreateUIToFP(Src, DstTy, "conv");
} else if (isa<llvm::IntegerType>(DstTy)) {
assert(SrcTy->isFloatingPointTy() && "Unknown real conversion");
if (DstType->isSignedIntegerOrEnumerationType())
Res = Builder.CreateFPToSI(Src, DstTy, "conv");
else
Res = Builder.CreateFPToUI(Src, DstTy, "conv");
} else {
assert(SrcTy->isFloatingPointTy() && DstTy->isFloatingPointTy() &&
"Unknown real conversion");
if (DstTy->getTypeID() < SrcTy->getTypeID())
Res = Builder.CreateFPTrunc(Src, DstTy, "conv");
else
Res = Builder.CreateFPExt(Src, DstTy, "conv");
}
if (DstTy != ResTy) {
if (!CGF.getContext().getLangOpts().HalfArgsAndReturns) {
assert(ResTy->isIntegerTy(16) && "Only half FP requires extra conversion");
Res = Builder.CreateCall(
CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16, CGF.CGM.FloatTy),
Res);
} else {
Res = Builder.CreateFPTrunc(Res, ResTy, "conv");
}
}
return Res;
}
/// 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,
SourceLocation Loc) {
// Get the source element type.
SrcTy = SrcTy->castAs<ComplexType>()->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, Loc);
Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy, Loc);
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, Loc);
}
Value *ScalarExprEmitter::EmitNullValue(QualType Ty) {
return CGF.EmitFromMemory(CGF.CGM.EmitNullConstant(Ty), Ty);
}
/// \brief Emit a sanitization check for the given "binary" operation (which
/// might actually be a unary increment which has been lowered to a binary
/// operation). The check passes if all values in \p Checks (which are \c i1),
/// are \c true.
void ScalarExprEmitter::EmitBinOpCheck(
ArrayRef<std::pair<Value *, SanitizerMask>> Checks, const BinOpInfo &Info) {
assert(CGF.IsSanitizerScope);
StringRef CheckName;
SmallVector<llvm::Constant *, 4> StaticData;
SmallVector<llvm::Value *, 2> DynamicData;
BinaryOperatorKind Opcode = Info.Opcode;
if (BinaryOperator::isCompoundAssignmentOp(Opcode))
Opcode = BinaryOperator::getOpForCompoundAssignment(Opcode);
StaticData.push_back(CGF.EmitCheckSourceLocation(Info.E->getExprLoc()));
const UnaryOperator *UO = dyn_cast<UnaryOperator>(Info.E);
if (UO && UO->getOpcode() == UO_Minus) {
CheckName = "negate_overflow";
StaticData.push_back(CGF.EmitCheckTypeDescriptor(UO->getType()));
DynamicData.push_back(Info.RHS);
} else {
if (BinaryOperator::isShiftOp(Opcode)) {
// Shift LHS negative or too large, or RHS out of bounds.
CheckName = "shift_out_of_bounds";
const BinaryOperator *BO = cast<BinaryOperator>(Info.E);
StaticData.push_back(
CGF.EmitCheckTypeDescriptor(BO->getLHS()->getType()));
StaticData.push_back(
CGF.EmitCheckTypeDescriptor(BO->getRHS()->getType()));
} else if (Opcode == BO_Div || Opcode == BO_Rem) {
// Divide or modulo by zero, or signed overflow (eg INT_MAX / -1).
CheckName = "divrem_overflow";
StaticData.push_back(CGF.EmitCheckTypeDescriptor(Info.Ty));
} else {
// Arithmetic overflow (+, -, *).
switch (Opcode) {
case BO_Add: CheckName = "add_overflow"; break;
case BO_Sub: CheckName = "sub_overflow"; break;
case BO_Mul: CheckName = "mul_overflow"; break;
default: llvm_unreachable("unexpected opcode for bin op check");
}
StaticData.push_back(CGF.EmitCheckTypeDescriptor(Info.Ty));
}
DynamicData.push_back(Info.LHS);
DynamicData.push_back(Info.RHS);
}
CGF.EmitCheck(Checks, CheckName, StaticData, DynamicData);
}
//===----------------------------------------------------------------------===//
// Visitor Methods
//===----------------------------------------------------------------------===//
Value *ScalarExprEmitter::VisitExpr(Expr *E) {
CGF.ErrorUnsupported(E, "scalar expression");
if (E->getType()->isVoidType())
return nullptr;
return llvm::UndefValue::get(CGF.ConvertType(E->getType()));
}
Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) {
// Vector Mask Case
if (E->getNumSubExprs() == 2 ||
(E->getNumSubExprs() == 3 && E->getExpr(2)->getType()->isVectorType())) {
Value *LHS = CGF.EmitScalarExpr(E->getExpr(0));
Value *RHS = CGF.EmitScalarExpr(E->getExpr(1));
Value *Mask;
llvm::VectorType *LTy = cast<llvm::VectorType>(LHS->getType());
unsigned LHSElts = LTy->getNumElements();
if (E->getNumSubExprs() == 3) {
Mask = CGF.EmitScalarExpr(E->getExpr(2));
// Shuffle LHS & RHS into one input vector.
SmallVector<llvm::Constant*, 32> concat;
for (unsigned i = 0; i != LHSElts; ++i) {
concat.push_back(Builder.getInt32(2*i));
concat.push_back(Builder.getInt32(2*i+1));
}
Value* CV = llvm::ConstantVector::get(concat);
LHS = Builder.CreateShuffleVector(LHS, RHS, CV, "concat");
LHSElts *= 2;
} else {
Mask = RHS;
}
llvm::VectorType *MTy = cast<llvm::VectorType>(Mask->getType());
// Mask off the high bits of each shuffle index.
Value *MaskBits =
llvm::ConstantInt::get(MTy, llvm::NextPowerOf2(LHSElts - 1) - 1);
Mask = Builder.CreateAnd(Mask, MaskBits, "mask");
// newv = undef
// mask = mask & maskbits
// for each elt
// n = extract mask i
// x = extract val n
// newv = insert newv, x, i
llvm::VectorType *RTy = llvm::VectorType::get(LTy->getElementType(),
MTy->getNumElements());
Value* NewV = llvm::UndefValue::get(RTy);
for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) {
Value *IIndx = llvm::ConstantInt::get(CGF.SizeTy, i);
Value *Indx = Builder.CreateExtractElement(Mask, IIndx, "shuf_idx");
Value *VExt = Builder.CreateExtractElement(LHS, Indx, "shuf_elt");
NewV = Builder.CreateInsertElement(NewV, VExt, IIndx, "shuf_ins");
}
return NewV;
}
Value* V1 = CGF.EmitScalarExpr(E->getExpr(0));
Value* V2 = CGF.EmitScalarExpr(E->getExpr(1));
SmallVector<llvm::Constant*, 32> indices;
for (unsigned i = 2; i < E->getNumSubExprs(); ++i) {
llvm::APSInt Idx = E->getShuffleMaskIdx(CGF.getContext(), i-2);
// Check for -1 and output it as undef in the IR.
if (Idx.isSigned() && Idx.isAllOnesValue())
indices.push_back(llvm::UndefValue::get(CGF.Int32Ty));
else
indices.push_back(Builder.getInt32(Idx.getZExtValue()));
}
Value *SV = llvm::ConstantVector::get(indices);
return Builder.CreateShuffleVector(V1, V2, SV, "shuffle");
}
Value *ScalarExprEmitter::VisitConvertVectorExpr(ConvertVectorExpr *E) {
QualType SrcType = E->getSrcExpr()->getType(),
DstType = E->getType();
Value *Src = CGF.EmitScalarExpr(E->getSrcExpr());
SrcType = CGF.getContext().getCanonicalType(SrcType);
DstType = CGF.getContext().getCanonicalType(DstType);
if (SrcType == DstType) return Src;
assert(SrcType->isVectorType() &&
"ConvertVector source type must be a vector");
assert(DstType->isVectorType() &&
"ConvertVector destination type must be a vector");
llvm::Type *SrcTy = Src->getType();
llvm::Type *DstTy = ConvertType(DstType);
// Ignore conversions like int -> uint.
if (SrcTy == DstTy)
return Src;
QualType SrcEltType = SrcType->getAs<VectorType>()->getElementType(),
DstEltType = DstType->getAs<VectorType>()->getElementType();
assert(SrcTy->isVectorTy() &&
"ConvertVector source IR type must be a vector");
assert(DstTy->isVectorTy() &&
"ConvertVector destination IR type must be a vector");
llvm::Type *SrcEltTy = SrcTy->getVectorElementType(),
*DstEltTy = DstTy->getVectorElementType();
if (DstEltType->isBooleanType()) {
assert((SrcEltTy->isFloatingPointTy() ||
isa<llvm::IntegerType>(SrcEltTy)) && "Unknown boolean conversion");
llvm::Value *Zero = llvm::Constant::getNullValue(SrcTy);
if (SrcEltTy->isFloatingPointTy()) {
return Builder.CreateFCmpUNE(Src, Zero, "tobool");
} else {
return Builder.CreateICmpNE(Src, Zero, "tobool");
}
}
// We have the arithmetic types: real int/float.
Value *Res = nullptr;
if (isa<llvm::IntegerType>(SrcEltTy)) {
bool InputSigned = SrcEltType->isSignedIntegerOrEnumerationType();
if (isa<llvm::IntegerType>(DstEltTy))
Res = Builder.CreateIntCast(Src, DstTy, InputSigned, "conv");
else if (InputSigned)
Res = Builder.CreateSIToFP(Src, DstTy, "conv");
else
Res = Builder.CreateUIToFP(Src, DstTy, "conv");
} else if (isa<llvm::IntegerType>(DstEltTy)) {
assert(SrcEltTy->isFloatingPointTy() && "Unknown real conversion");
if (DstEltType->isSignedIntegerOrEnumerationType())
Res = Builder.CreateFPToSI(Src, DstTy, "conv");
else
Res = Builder.CreateFPToUI(Src, DstTy, "conv");
} else {
assert(SrcEltTy->isFloatingPointTy() && DstEltTy->isFloatingPointTy() &&
"Unknown real conversion");
if (DstEltTy->getTypeID() < SrcEltTy->getTypeID())
Res = Builder.CreateFPTrunc(Src, DstTy, "conv");
else
Res = Builder.CreateFPExt(Src, DstTy, "conv");
}
return Res;
}
Value *ScalarExprEmitter::VisitMemberExpr(MemberExpr *E) {
llvm::APSInt Value;
if (E->EvaluateAsInt(Value, CGF.getContext(), Expr::SE_AllowSideEffects)) {
if (E->isArrow())
CGF.EmitScalarExpr(E->getBase());
else
EmitLValue(E->getBase());
return Builder.getInt(Value);
}
return EmitLoadOfLValue(E);
}
Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
TestAndClearIgnoreResultAssign();
// 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());
QualType IdxTy = E->getIdx()->getType();
if (CGF.SanOpts.has(SanitizerKind::ArrayBounds))
CGF.EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, /*Accessed*/true);
return Builder.CreateExtractElement(Base, Idx, "vecext");
}
static llvm::Constant *getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx,
unsigned Off, llvm::Type *I32Ty) {
int MV = SVI->getMaskValue(Idx);
if (MV == -1)
return llvm::UndefValue::get(I32Ty);
return llvm::ConstantInt::get(I32Ty, Off+MV);
}
static llvm::Constant *getAsInt32(llvm::ConstantInt *C, llvm::Type *I32Ty) {
if (C->getBitWidth() != 32) {
assert(llvm::ConstantInt::isValueValidForType(I32Ty,
C->getZExtValue()) &&
"Index operand too large for shufflevector mask!");
return llvm::ConstantInt::get(I32Ty, C->getZExtValue());
}
return C;
}
Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) {
bool Ignore = TestAndClearIgnoreResultAssign();
(void)Ignore;
assert (Ignore == false && "init list ignored");
unsigned NumInitElements = E->getNumInits();
if (E->hadArrayRangeDesignator())
CGF.ErrorUnsupported(E, "GNU array range designator extension");
llvm::VectorType *VType =
dyn_cast<llvm::VectorType>(ConvertType(E->getType()));
if (!VType) {
if (NumInitElements == 0) {
// C++11 value-initialization for the scalar.
return EmitNullValue(E->getType());
}
// We have a scalar in braces. Just use the first element.
return Visit(E->getInit(0));
}
unsigned ResElts = VType->getNumElements();
// Loop over initializers collecting the Value for each, and remembering
// whether the source was swizzle (ExtVectorElementExpr). This will allow
// us to fold the shuffle for the swizzle into the shuffle for the vector
// initializer, since LLVM optimizers generally do not want to touch
// shuffles.
unsigned CurIdx = 0;
bool VIsUndefShuffle = false;
llvm::Value *V = llvm::UndefValue::get(VType);
for (unsigned i = 0; i != NumInitElements; ++i) {
Expr *IE = E->getInit(i);
Value *Init = Visit(IE);
SmallVector<llvm::Constant*, 16> Args;
llvm::VectorType *VVT = dyn_cast<llvm::VectorType>(Init->getType());
// Handle scalar elements. If the scalar initializer is actually one
// element of a different vector of the same width, use shuffle instead of
// extract+insert.
if (!VVT) {
if (isa<ExtVectorElementExpr>(IE)) {
llvm::ExtractElementInst *EI = cast<llvm::ExtractElementInst>(Init);
if (EI->getVectorOperandType()->getNumElements() == ResElts) {
llvm::ConstantInt *C = cast<llvm::ConstantInt>(EI->getIndexOperand());
Value *LHS = nullptr, *RHS = nullptr;
if (CurIdx == 0) {
// insert into undef -> shuffle (src, undef)
// shufflemask must use an i32
Args.push_back(getAsInt32(C, CGF.Int32Ty));
Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
LHS = EI->getVectorOperand();
RHS = V;
VIsUndefShuffle = true;
} else if (VIsUndefShuffle) {
// insert into undefshuffle && size match -> shuffle (v, src)
llvm::ShuffleVectorInst *SVV = cast<llvm::ShuffleVectorInst>(V);
for (unsigned j = 0; j != CurIdx; ++j)
Args.push_back(getMaskElt(SVV, j, 0, CGF.Int32Ty));
Args.push_back(Builder.getInt32(ResElts + C->getZExtValue()));
Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
LHS = cast<llvm::ShuffleVectorInst>(V)->getOperand(0);
RHS = EI->getVectorOperand();
VIsUndefShuffle = false;
}
if (!Args.empty()) {
llvm::Constant *Mask = llvm::ConstantVector::get(Args);
V = Builder.CreateShuffleVector(LHS, RHS, Mask);
++CurIdx;
continue;
}
}
}
V = Builder.CreateInsertElement(V, Init, Builder.getInt32(CurIdx),
"vecinit");
VIsUndefShuffle = false;
++CurIdx;
continue;
}
unsigned InitElts = VVT->getNumElements();
// If the initializer is an ExtVecEltExpr (a swizzle), and the swizzle's
// input is the same width as the vector being constructed, generate an
// optimized shuffle of the swizzle input into the result.
unsigned Offset = (CurIdx == 0) ? 0 : ResElts;
if (isa<ExtVectorElementExpr>(IE)) {
llvm::ShuffleVectorInst *SVI = cast<llvm::ShuffleVectorInst>(Init);
Value *SVOp = SVI->getOperand(0);
llvm::VectorType *OpTy = cast<llvm::VectorType>(SVOp->getType());
if (OpTy->getNumElements() == ResElts) {
for (unsigned j = 0; j != CurIdx; ++j) {
// If the current vector initializer is a shuffle with undef, merge
// this shuffle directly into it.
if (VIsUndefShuffle) {
Args.push_back(getMaskElt(cast<llvm::ShuffleVectorInst>(V), j, 0,
CGF.Int32Ty));
} else {
Args.push_back(Builder.getInt32(j));
}
}
for (unsigned j = 0, je = InitElts; j != je; ++j)
Args.push_back(getMaskElt(SVI, j, Offset, CGF.Int32Ty));
Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
if (VIsUndefShuffle)
V = cast<llvm::ShuffleVectorInst>(V)->getOperand(0);
Init = SVOp;
}
}
// Extend init to result vector length, and then shuffle its contribution
// to the vector initializer into V.
if (Args.empty()) {
for (unsigned j = 0; j != InitElts; ++j)
Args.push_back(Builder.getInt32(j));
Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
llvm::Constant *Mask = llvm::ConstantVector::get(Args);
Init = Builder.CreateShuffleVector(Init, llvm::UndefValue::get(VVT),
Mask, "vext");
Args.clear();
for (unsigned j = 0; j != CurIdx; ++j)
Args.push_back(Builder.getInt32(j));
for (unsigned j = 0; j != InitElts; ++j)
Args.push_back(Builder.getInt32(j+Offset));
Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
}
// If V is undef, make sure it ends up on the RHS of the shuffle to aid
// merging subsequent shuffles into this one.
if (CurIdx == 0)
std::swap(V, Init);
llvm::Constant *Mask = llvm::ConstantVector::get(Args);
V = Builder.CreateShuffleVector(V, Init, Mask, "vecinit");
VIsUndefShuffle = isa<llvm::UndefValue>(Init);
CurIdx += InitElts;
}
// FIXME: evaluate codegen vs. shuffling against constant null vector.
// Emit remaining default initializers.
llvm::Type *EltTy = VType->getElementType();
// Emit remaining default initializers
for (/* Do not initialize i*/; CurIdx < ResElts; ++CurIdx) {
Value *Idx = Builder.getInt32(CurIdx);
llvm::Value *Init = llvm::Constant::getNullValue(EltTy);
V = Builder.CreateInsertElement(V, Init, Idx, "vecinit");
}
return V;
}
bool CodeGenFunction::ShouldNullCheckClassCastValue(const CastExpr *CE) {
const Expr *E = CE->getSubExpr();
if (CE->getCastKind() == CK_UncheckedDerivedToBase)
return false;
if (isa<CXXThisExpr>(E->IgnoreParens())) {
// We always assume that 'this' is never null.
return false;
}
if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(CE)) {
// And that glvalue casts are never null.
if (ICE->getValueKind() != VK_RValue)
return false;
}
return true;
}
// 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::VisitCastExpr(CastExpr *CE) {
Expr *E = CE->getSubExpr();
QualType DestTy = CE->getType();
CastKind Kind = CE->getCastKind();
// These cases are generally not written to ignore the result of
// evaluating their sub-expressions, so we clear this now.
bool Ignored = TestAndClearIgnoreResultAssign();
// Since almost all cast kinds apply to scalars, this switch doesn't have
// a default case, so the compiler will warn on a missing case. The cases
// are in the same order as in the CastKind enum.
switch (Kind) {
case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!");
case CK_BuiltinFnToFnPtr:
llvm_unreachable("builtin functions are handled elsewhere");
case CK_LValueBitCast:
case CK_ObjCObjectLValueCast: {
Address Addr = EmitLValue(E).getAddress();
Addr = Builder.CreateElementBitCast(Addr, CGF.ConvertTypeForMem(DestTy));
LValue LV = CGF.MakeAddrLValue(Addr, DestTy);
return EmitLoadOfLValue(LV, CE->getExprLoc());
}
case CK_CPointerToObjCPointerCast:
case CK_BlockPointerToObjCPointerCast:
case CK_AnyPointerToBlockPointerCast:
case CK_BitCast: {
Value *Src = Visit(const_cast<Expr*>(E));
llvm::Type *SrcTy = Src->getType();
llvm::Type *DstTy = ConvertType(DestTy);
if (SrcTy->isPtrOrPtrVectorTy() && DstTy->isPtrOrPtrVectorTy() &&
SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace()) {
llvm_unreachable("wrong cast for pointers in different address spaces"
"(must be an address space cast)!");
}
if (CGF.SanOpts.has(SanitizerKind::CFIUnrelatedCast)) {
if (auto PT = DestTy->getAs<PointerType>())
CGF.EmitVTablePtrCheckForCast(PT->getPointeeType(), Src,
/*MayBeNull=*/true,
CodeGenFunction::CFITCK_UnrelatedCast,
CE->getLocStart());
}
return Builder.CreateBitCast(Src, DstTy);
}
case CK_AddressSpaceConversion: {
Value *Src = Visit(const_cast<Expr*>(E));
return Builder.CreateAddrSpaceCast(Src, ConvertType(DestTy));
}
case CK_AtomicToNonAtomic:
case CK_NonAtomicToAtomic:
case CK_NoOp:
case CK_UserDefinedConversion:
return Visit(const_cast<Expr*>(E));
case CK_BaseToDerived: {
const CXXRecordDecl *DerivedClassDecl = DestTy->getPointeeCXXRecordDecl();
assert(DerivedClassDecl && "BaseToDerived arg isn't a C++ object pointer!");
Address Base = CGF.EmitPointerWithAlignment(E);
Address Derived =
CGF.GetAddressOfDerivedClass(Base, DerivedClassDecl,
CE->path_begin(), CE->path_end(),
CGF.ShouldNullCheckClassCastValue(CE));
// C++11 [expr.static.cast]p11: Behavior is undefined if a downcast is
// performed and the object is not of the derived type.
if (CGF.sanitizePerformTypeCheck())
CGF.EmitTypeCheck(CodeGenFunction::TCK_DowncastPointer, CE->getExprLoc(),
Derived.getPointer(), DestTy->getPointeeType());
if (CGF.SanOpts.has(SanitizerKind::CFIDerivedCast))
CGF.EmitVTablePtrCheckForCast(DestTy->getPointeeType(),
Derived.getPointer(),
/*MayBeNull=*/true,
CodeGenFunction::CFITCK_DerivedCast,
CE->getLocStart());
return Derived.getPointer();
}
case CK_UncheckedDerivedToBase:
case CK_DerivedToBase: {
// The EmitPointerWithAlignment path does this fine; just discard
// the alignment.
return CGF.EmitPointerWithAlignment(CE).getPointer();
}
case CK_Dynamic: {
Address V = CGF.EmitPointerWithAlignment(E);
const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(CE);
return CGF.EmitDynamicCast(V, DCE);
}
case CK_ArrayToPointerDecay:
return CGF.EmitArrayToPointerDecay(E).getPointer();
case CK_FunctionToPointerDecay:
return EmitLValue(E).getPointer();
case CK_NullToPointer:
if (MustVisitNullValue(E))
(void) Visit(E);
return llvm::ConstantPointerNull::get(
cast<llvm::PointerType>(ConvertType(DestTy)));
case CK_NullToMemberPointer: {
if (MustVisitNullValue(E))
(void) Visit(E);
const MemberPointerType *MPT = CE->getType()->getAs<MemberPointerType>();
return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT);
}
case CK_ReinterpretMemberPointer:
case CK_BaseToDerivedMemberPointer:
case CK_DerivedToBaseMemberPointer: {
Value *Src = Visit(E);
// Note that the AST doesn't distinguish between checked and
// unchecked member pointer conversions, so we always have to
// implement checked conversions here. This is inefficient when
// actual control flow may be required in order to perform the
// check, which it is for data member pointers (but not member
// function pointers on Itanium and ARM).
return CGF.CGM.getCXXABI().EmitMemberPointerConversion(CGF, CE, Src);
}
case CK_ARCProduceObject:
return CGF.EmitARCRetainScalarExpr(E);
case CK_ARCConsumeObject:
return CGF.EmitObjCConsumeObject(E->getType(), Visit(E));
case CK_ARCReclaimReturnedObject:
return CGF.EmitARCReclaimReturnedObject(E, /*allowUnsafe*/ Ignored);
case CK_ARCExtendBlockObject:
return CGF.EmitARCExtendBlockObject(E);
case CK_CopyAndAutoreleaseBlockObject:
return CGF.EmitBlockCopyAndAutorelease(Visit(E), E->getType());
case CK_FloatingRealToComplex:
case CK_FloatingComplexCast:
case CK_IntegralRealToComplex:
case CK_IntegralComplexCast:
case CK_IntegralComplexToFloatingComplex:
case CK_FloatingComplexToIntegralComplex:
case CK_ConstructorConversion:
case CK_ToUnion:
llvm_unreachable("scalar cast to non-scalar value");
case CK_LValueToRValue:
assert(CGF.getContext().hasSameUnqualifiedType(E->getType(), DestTy));
assert(E->isGLValue() && "lvalue-to-rvalue applied to r-value!");
return Visit(const_cast<Expr*>(E));
case CK_IntegralToPointer: {
Value *Src = Visit(const_cast<Expr*>(E));
// First, convert to the correct width so that we control the kind of
// extension.
llvm::Type *MiddleTy = CGF.IntPtrTy;
bool InputSigned = E->getType()->isSignedIntegerOrEnumerationType();
llvm::Value* IntResult =
Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv");
return Builder.CreateIntToPtr(IntResult, ConvertType(DestTy));
}
case CK_PointerToIntegral:
assert(!DestTy->isBooleanType() && "bool should use PointerToBool");
return Builder.CreatePtrToInt(Visit(E), ConvertType(DestTy));
case CK_ToVoid: {
CGF.EmitIgnoredExpr(E);
return nullptr;
}
case CK_VectorSplat: {
llvm::Type *DstTy = ConvertType(DestTy);
Value *Elt = Visit(const_cast<Expr*>(E));
// Splat the element across to all elements
unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements();
return Builder.CreateVectorSplat(NumElements, Elt, "splat");
}
case CK_IntegralCast:
case CK_IntegralToFloating:
case CK_FloatingToIntegral:
case CK_FloatingCast:
return EmitScalarConversion(Visit(E), E->getType(), DestTy,
CE->getExprLoc());
case CK_BooleanToSignedIntegral:
return EmitScalarConversion(Visit(E), E->getType(), DestTy,
CE->getExprLoc(),
/*TreatBooleanAsSigned=*/true);
case CK_IntegralToBoolean:
return EmitIntToBoolConversion(Visit(E));
case CK_PointerToBoolean:
return EmitPointerToBoolConversion(Visit(E));
case CK_FloatingToBoolean:
return EmitFloatToBoolConversion(Visit(E));
case CK_MemberPointerToBoolean: {
llvm::Value *MemPtr = Visit(E);
const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>();
return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, MemPtr, MPT);
}
case CK_FloatingComplexToReal:
case CK_IntegralComplexToReal:
return CGF.EmitComplexExpr(E, false, true).first;
case CK_FloatingComplexToBoolean:
case CK_IntegralComplexToBoolean: {
CodeGenFunction::ComplexPairTy V = CGF.EmitComplexExpr(E);
// TODO: kill this function off, inline appropriate case here
return EmitComplexToScalarConversion(V, E->getType(), DestTy,
CE->getExprLoc());
}
case CK_ZeroToOCLEvent: {
assert(DestTy->isEventT() && "CK_ZeroToOCLEvent cast on non-event type");
return llvm::Constant::getNullValue(ConvertType(DestTy));
}
}
llvm_unreachable("unknown scalar cast");
}
Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) {
CodeGenFunction::StmtExprEvaluation eval(CGF);
Address RetAlloca = CGF.EmitCompoundStmt(*E->getSubStmt(),
!E->getType()->isVoidType());
if (!RetAlloca.isValid())
return nullptr;
return CGF.EmitLoadOfScalar(CGF.MakeAddrLValue(RetAlloca, E->getType()),
E->getExprLoc());
}
//===----------------------------------------------------------------------===//
// Unary Operators
//===----------------------------------------------------------------------===//
static BinOpInfo createBinOpInfoFromIncDec(const UnaryOperator *E,
llvm::Value *InVal, bool IsInc) {
BinOpInfo BinOp;
BinOp.LHS = InVal;
BinOp.RHS = llvm::ConstantInt::get(InVal->getType(), 1, false);
BinOp.Ty = E->getType();
BinOp.Opcode = IsInc ? BO_Add : BO_Sub;
BinOp.FPContractable = false;
BinOp.E = E;
return BinOp;
}
llvm::Value *ScalarExprEmitter::EmitIncDecConsiderOverflowBehavior(
const UnaryOperator *E, llvm::Value *InVal, bool IsInc) {
llvm::Value *Amount =
llvm::ConstantInt::get(InVal->getType(), IsInc ? 1 : -1, true);
StringRef Name = IsInc ? "inc" : "dec";
switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
case LangOptions::SOB_Defined:
return Builder.CreateAdd(InVal, Amount, Name);
case LangOptions::SOB_Undefined:
if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
return Builder.CreateNSWAdd(InVal, Amount, Name);
// Fall through.
case LangOptions::SOB_Trapping:
return EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(E, InVal, IsInc));
}
llvm_unreachable("Unknown SignedOverflowBehaviorTy");
}
llvm::Value *
ScalarExprEmitter::EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
bool isInc, bool isPre) {
QualType type = E->getSubExpr()->getType();
llvm::PHINode *atomicPHI = nullptr;
llvm::Value *value;
llvm::Value *input;
int amount = (isInc ? 1 : -1);
if (const AtomicType *atomicTy = type->getAs<AtomicType>()) {
type = atomicTy->getValueType();
if (isInc && type->isBooleanType()) {
llvm::Value *True = CGF.EmitToMemory(Builder.getTrue(), type);
if (isPre) {
Builder.CreateStore(True, LV.getAddress(), LV.isVolatileQualified())
->setAtomic(llvm::SequentiallyConsistent);
return Builder.getTrue();
}
// For atomic bool increment, we just store true and return it for
// preincrement, do an atomic swap with true for postincrement
return Builder.CreateAtomicRMW(llvm::AtomicRMWInst::Xchg,
LV.getPointer(), True, llvm::SequentiallyConsistent);
}
// Special case for atomic increment / decrement on integers, emit
// atomicrmw instructions. We skip this if we want to be doing overflow
// checking, and fall into the slow path with the atomic cmpxchg loop.
if (!type->isBooleanType() && type->isIntegerType() &&
!(type->isUnsignedIntegerType() &&
CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) &&
CGF.getLangOpts().getSignedOverflowBehavior() !=
LangOptions::SOB_Trapping) {
llvm::AtomicRMWInst::BinOp aop = isInc ? llvm::AtomicRMWInst::Add :
llvm::AtomicRMWInst::Sub;
llvm::Instruction::BinaryOps op = isInc ? llvm::Instruction::Add :
llvm::Instruction::Sub;
llvm::Value *amt = CGF.EmitToMemory(
llvm::ConstantInt::get(ConvertType(type), 1, true), type);
llvm::Value *old = Builder.CreateAtomicRMW(aop,
LV.getPointer(), amt, llvm::SequentiallyConsistent);
return isPre ? Builder.CreateBinOp(op, old, amt) : old;
}
value = EmitLoadOfLValue(LV, E->getExprLoc());
input = value;
// For every other atomic operation, we need to emit a load-op-cmpxchg loop
llvm::BasicBlock *startBB = Builder.GetInsertBlock();
llvm::BasicBlock *opBB = CGF.createBasicBlock("atomic_op", CGF.CurFn);
value = CGF.EmitToMemory(value, type);
Builder.CreateBr(opBB);
Builder.SetInsertPoint(opBB);
atomicPHI = Builder.CreatePHI(value->getType(), 2);
atomicPHI->addIncoming(value, startBB);
value = atomicPHI;
} else {
value = EmitLoadOfLValue(LV, E->getExprLoc());
input = value;
}
// Special case of integer increment that we have to check first: bool++.
// Due to promotion rules, we get:
// bool++ -> bool = bool + 1
// -> bool = (int)bool + 1
// -> bool = ((int)bool + 1 != 0)
// An interesting aspect of this is that increment is always true.
// Decrement does not have this property.
if (isInc && type->isBooleanType()) {
value = Builder.getTrue();
// Most common case by far: integer increment.
} else if (type->isIntegerType()) {
// Note that signed integer inc/dec with width less than int can't
// overflow because of promotion rules; we're just eliding a few steps here.
bool CanOverflow = value->getType()->getIntegerBitWidth() >=
CGF.IntTy->getIntegerBitWidth();
if (CanOverflow && type->isSignedIntegerOrEnumerationType()) {
value = EmitIncDecConsiderOverflowBehavior(E, value, isInc);
} else if (CanOverflow && type->isUnsignedIntegerType() &&
CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) {
value =
EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(E, value, isInc));
} else {
llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount, true);
value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec");
}
// Next most common: pointer increment.
} else if (const PointerType *ptr = type->getAs<PointerType>()) {
QualType type = ptr->getPointeeType();
// VLA types don't have constant size.
if (const VariableArrayType *vla
= CGF.getContext().getAsVariableArrayType(type)) {
llvm::Value *numElts = CGF.getVLASize(vla).first;
if (!isInc) numElts = Builder.CreateNSWNeg(numElts, "vla.negsize");
if (CGF.getLangOpts().isSignedOverflowDefined())
value = Builder.CreateGEP(value, numElts, "vla.inc");
else
value = Builder.CreateInBoundsGEP(value, numElts, "vla.inc");
// Arithmetic on function pointers (!) is just +-1.
} else if (type->isFunctionType()) {
llvm::Value *amt = Builder.getInt32(amount);
value = CGF.EmitCastToVoidPtr(value);
if (CGF.getLangOpts().isSignedOverflowDefined())
value = Builder.CreateGEP(value, amt, "incdec.funcptr");
else
value = Builder.CreateInBoundsGEP(value, amt, "incdec.funcptr");
value = Builder.CreateBitCast(value, input->getType());
// For everything else, we can just do a simple increment.
} else {
llvm::Value *amt = Builder.getInt32(amount);
if (CGF.getLangOpts().isSignedOverflowDefined())
value = Builder.CreateGEP(value, amt, "incdec.ptr");
else
value = Builder.CreateInBoundsGEP(value, amt, "incdec.ptr");
}
// Vector increment/decrement.
} else if (type->isVectorType()) {
if (type->hasIntegerRepresentation()) {
llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount);
value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec");
} else {
value = Builder.CreateFAdd(
value,
llvm::ConstantFP::get(value->getType(), amount),
isInc ? "inc" : "dec");
}
// Floating point.
} else if (type->isRealFloatingType()) {
// Add the inc/dec to the real part.
llvm::Value *amt;
if (type->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
// Another special case: half FP increment should be done via float
if (!CGF.getContext().getLangOpts().HalfArgsAndReturns) {
value = Builder.CreateCall(
CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16,
CGF.CGM.FloatTy),
input, "incdec.conv");
} else {
value = Builder.CreateFPExt(input, CGF.CGM.FloatTy, "incdec.conv");
}
}
if (value->getType()->isFloatTy())
amt = llvm::ConstantFP::get(VMContext,
llvm::APFloat(static_cast<float>(amount)));
else if (value->getType()->isDoubleTy())
amt = llvm::ConstantFP::get(VMContext,
llvm::APFloat(static_cast<double>(amount)));
else {
// Remaining types are either Half or LongDouble. Convert from float.
llvm::APFloat F(static_cast<float>(amount));
bool ignored;
// Don't use getFloatTypeSemantics because Half isn't
// necessarily represented using the "half" LLVM type.
F.convert(value->getType()->isHalfTy()
? CGF.getTarget().getHalfFormat()
: CGF.getTarget().getLongDoubleFormat(),
llvm::APFloat::rmTowardZero, &ignored);
amt = llvm::ConstantFP::get(VMContext, F);
}
value = Builder.CreateFAdd(value, amt, isInc ? "inc" : "dec");
if (type->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
if (!CGF.getContext().getLangOpts().HalfArgsAndReturns) {
value = Builder.CreateCall(
CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16,
CGF.CGM.FloatTy),
value, "incdec.conv");
} else {
value = Builder.CreateFPTrunc(value, input->getType(), "incdec.conv");
}
}
// Objective-C pointer types.
} else {
const ObjCObjectPointerType *OPT = type->castAs<ObjCObjectPointerType>();
value = CGF.EmitCastToVoidPtr(value);
CharUnits size = CGF.getContext().getTypeSizeInChars(OPT->getObjectType());
if (!isInc) size = -size;
llvm::Value *sizeValue =
llvm::ConstantInt::get(CGF.SizeTy, size.getQuantity());
if (CGF.getLangOpts().isSignedOverflowDefined())
value = Builder.CreateGEP(value, sizeValue, "incdec.objptr");
else
value = Builder.CreateInBoundsGEP(value, sizeValue, "incdec.objptr");
value = Builder.CreateBitCast(value, input->getType());
}
if (atomicPHI) {
llvm::BasicBlock *opBB = Builder.GetInsertBlock();
llvm::BasicBlock *contBB = CGF.createBasicBlock("atomic_cont", CGF.CurFn);
auto Pair = CGF.EmitAtomicCompareExchange(
LV, RValue::get(atomicPHI), RValue::get(value), E->getExprLoc());
llvm::Value *old = CGF.EmitToMemory(Pair.first.getScalarVal(), type);
llvm::Value *success = Pair.second;
atomicPHI->addIncoming(old, opBB);
Builder.CreateCondBr(success, contBB, opBB);
Builder.SetInsertPoint(contBB);
return isPre ? value : input;
}
// Store the updated result through the lvalue.
if (LV.isBitField())
CGF.EmitStoreThroughBitfieldLValue(RValue::get(value), LV, &value);
else
CGF.EmitStoreThroughLValue(RValue::get(value), LV);
// If this is a postinc, return the value read from memory, otherwise use the
// updated value.
return isPre ? value : input;
}
Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
TestAndClearIgnoreResultAssign();
// Emit unary minus with EmitSub so we handle overflow cases etc.
BinOpInfo BinOp;
BinOp.RHS = Visit(E->getSubExpr());
if (BinOp.RHS->getType()->isFPOrFPVectorTy())
BinOp.LHS = llvm::ConstantFP::getZeroValueForNegation(BinOp.RHS->getType());
else
BinOp.LHS = llvm::Constant::getNullValue(BinOp.RHS->getType());
BinOp.Ty = E->getType();
BinOp.Opcode = BO_Sub;
BinOp.FPContractable = false;
BinOp.E = E;
return EmitSub(BinOp);
}
Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
TestAndClearIgnoreResultAssign();
Value *Op = Visit(E->getSubExpr());
return Builder.CreateNot(Op, "neg");
}
Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) {
// Perform vector logical not on comparison with zero vector.
if (E->getType()->isExtVectorType()) {
Value *Oper = Visit(E->getSubExpr());
Value *Zero = llvm::Constant::getNullValue(Oper->getType());
Value *Result;
if (Oper->getType()->isFPOrFPVectorTy())
Result = Builder.CreateFCmp(llvm::CmpInst::FCMP_OEQ, Oper, Zero, "cmp");
else
Result = Builder.CreateICmp(llvm::CmpInst::ICMP_EQ, Oper, Zero, "cmp");
return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext");
}
// 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 the expr type.
return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext");
}
Value *ScalarExprEmitter::VisitOffsetOfExpr(OffsetOfExpr *E) {
// Try folding the offsetof to a constant.
llvm::APSInt Value;
if (E->EvaluateAsInt(Value, CGF.getContext()))
return Builder.getInt(Value);
// Loop over the components of the offsetof to compute the value.
unsigned n = E->getNumComponents();
llvm::Type* ResultType = ConvertType(E->getType());
llvm::Value* Result = llvm::Constant::getNullValue(ResultType);
QualType CurrentType = E->getTypeSourceInfo()->getType();
for (unsigned i = 0; i != n; ++i) {
OffsetOfNode ON = E->getComponent(i);
llvm::Value *Offset = nullptr;
switch (ON.getKind()) {
case OffsetOfNode::Array: {
// Compute the index
Expr *IdxExpr = E->getIndexExpr(ON.getArrayExprIndex());
llvm::Value* Idx = CGF.EmitScalarExpr(IdxExpr);
bool IdxSigned = IdxExpr->getType()->isSignedIntegerOrEnumerationType();
Idx = Builder.CreateIntCast(Idx, ResultType, IdxSigned, "conv");
// Save the element type
CurrentType =
CGF.getContext().getAsArrayType(CurrentType)->getElementType();
// Compute the element size
llvm::Value* ElemSize = llvm::ConstantInt::get(ResultType,
CGF.getContext().getTypeSizeInChars(CurrentType).getQuantity());
// Multiply out to compute the result
Offset = Builder.CreateMul(Idx, ElemSize);
break;
}
case OffsetOfNode::Field: {
FieldDecl *MemberDecl = ON.getField();
RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl();
const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD);
// Compute the index of the field in its parent.
unsigned i = 0;
// FIXME: It would be nice if we didn't have to loop here!
for (RecordDecl::field_iterator Field = RD->field_begin(),
FieldEnd = RD->field_end();
Field != FieldEnd; ++Field, ++i) {
if (*Field == MemberDecl)
break;
}
assert(i < RL.getFieldCount() && "offsetof field in wrong type");
// Compute the offset to the field
int64_t OffsetInt = RL.getFieldOffset(i) /
CGF.getContext().getCharWidth();
Offset = llvm::ConstantInt::get(ResultType, OffsetInt);
// Save the element type.
CurrentType = MemberDecl->getType();
break;
}
case OffsetOfNode::Identifier:
llvm_unreachable("dependent __builtin_offsetof");
case OffsetOfNode::Base: {
if (ON.getBase()->isVirtual()) {
CGF.ErrorUnsupported(E, "virtual base in offsetof");
continue;
}
RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl();
const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD);
// Save the element type.
CurrentType = ON.getBase()->getType();
// Compute the offset to the base.
const RecordType *BaseRT = CurrentType->getAs<RecordType>();
CXXRecordDecl *BaseRD = cast<CXXRecordDecl>(BaseRT->getDecl());
CharUnits OffsetInt = RL.getBaseClassOffset(BaseRD);
Offset = llvm::ConstantInt::get(ResultType, OffsetInt.getQuantity());
break;
}
}
Result = Builder.CreateAdd(Result, Offset);
}
return Result;
}
/// VisitUnaryExprOrTypeTraitExpr - Return the size or alignment of the type of
/// argument of the sizeof expression as an integer.
Value *
ScalarExprEmitter::VisitUnaryExprOrTypeTraitExpr(
const UnaryExprOrTypeTraitExpr *E) {
QualType TypeToSize = E->getTypeOfArgument();
if (E->getKind() == UETT_SizeOf) {
if (const VariableArrayType *VAT =
CGF.getContext().getAsVariableArrayType(TypeToSize)) {
if (E->isArgumentType()) {
// sizeof(type) - make sure to emit the VLA size.
CGF.EmitVariablyModifiedType(TypeToSize);
} else {
// C99 6.5.3.4p2: If the argument is an expression of type
// VLA, it is evaluated.
CGF.EmitIgnoredExpr(E->getArgumentExpr());
}
QualType eltType;
llvm::Value *numElts;
std::tie(numElts, eltType) = CGF.getVLASize(VAT);
llvm::Value *size = numElts;
// Scale the number of non-VLA elements by the non-VLA element size.
CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType);
if (!eltSize.isOne())
size = CGF.Builder.CreateNUWMul(CGF.CGM.getSize(eltSize), numElts);
return size;
}
} else if (E->getKind() == UETT_OpenMPRequiredSimdAlign) {
auto Alignment =
CGF.getContext()
.toCharUnitsFromBits(CGF.getContext().getOpenMPDefaultSimdAlign(
E->getTypeOfArgument()->getPointeeType()))
.getQuantity();
return llvm::ConstantInt::get(CGF.SizeTy, Alignment);
}
// If this isn't sizeof(vla), the result must be constant; use the constant
// folding logic so we don't have to duplicate it here.
return Builder.getInt(E->EvaluateKnownConstInt(CGF.getContext()));
}
Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) {
Expr *Op = E->getSubExpr();
if (Op->getType()->isAnyComplexType()) {
// If it's an l-value, load through the appropriate subobject l-value.
// Note that we have to ask E because Op might be an l-value that
// this won't work for, e.g. an Obj-C property.
if (E->isGLValue())
return CGF.EmitLoadOfLValue(CGF.EmitLValue(E),
E->getExprLoc()).getScalarVal();
// Otherwise, calculate and project.
return CGF.EmitComplexExpr(Op, false, true).first;
}
return Visit(Op);
}
Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) {
Expr *Op = E->getSubExpr();
if (Op->getType()->isAnyComplexType()) {
// If it's an l-value, load through the appropriate subobject l-value.
// Note that we have to ask E because Op might be an l-value that
// this won't work for, e.g. an Obj-C property.
if (Op->isGLValue())
return CGF.EmitLoadOfLValue(CGF.EmitLValue(E),
E->getExprLoc()).getScalarVal();
// Otherwise, calculate and project.
return CGF.EmitComplexExpr(Op, true, false).second;
}
// __imag on a scalar returns zero. Emit the subexpr to ensure side
// effects are evaluated, but not the actual value.
if (Op->isGLValue())
CGF.EmitLValue(Op);
else
CGF.EmitScalarExpr(Op, true);
return llvm::Constant::getNullValue(ConvertType(E->getType()));
}
//===----------------------------------------------------------------------===//
// Binary Operators
//===----------------------------------------------------------------------===//
BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) {
TestAndClearIgnoreResultAssign();
BinOpInfo Result;
Result.LHS = Visit(E->getLHS());
Result.RHS = Visit(E->getRHS());
Result.Ty = E->getType();
Result.Opcode = E->getOpcode();
Result.FPContractable = E->isFPContractable();
Result.E = E;
return Result;
}
LValue ScalarExprEmitter::EmitCompoundAssignLValue(
const CompoundAssignOperator *E,
Value *(ScalarExprEmitter::*Func)(const BinOpInfo &),
Value *&Result) {
QualType LHSTy = E->getLHS()->getType();
BinOpInfo OpInfo;
if (E->getComputationResultType()->isAnyComplexType())
return CGF.EmitScalarCompoundAssignWithComplex(E, Result);
// Emit the RHS first. __block variables need to have the rhs evaluated
// first, plus this should improve codegen a little.
OpInfo.RHS = Visit(E->getRHS());
OpInfo.Ty = E->getComputationResultType();
OpInfo.Opcode = E->getOpcode();
OpInfo.FPContractable = E->isFPContractable();
OpInfo.E = E;
// Load/convert the LHS.
LValue LHSLV = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store);
llvm::PHINode *atomicPHI = nullptr;
if (const AtomicType *atomicTy = LHSTy->getAs<AtomicType>()) {
QualType type = atomicTy->getValueType();
if (!type->isBooleanType() && type->isIntegerType() &&
!(type->isUnsignedIntegerType() &&
CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) &&
CGF.getLangOpts().getSignedOverflowBehavior() !=
LangOptions::SOB_Trapping) {
llvm::AtomicRMWInst::BinOp aop = llvm::AtomicRMWInst::BAD_BINOP;
switch (OpInfo.Opcode) {
// We don't have atomicrmw operands for *, %, /, <<, >>
case BO_MulAssign: case BO_DivAssign:
case BO_RemAssign:
case BO_ShlAssign:
case BO_ShrAssign:
break;
case BO_AddAssign:
aop = llvm::AtomicRMWInst::Add;
break;
case BO_SubAssign:
aop = llvm::AtomicRMWInst::Sub;
break;
case BO_AndAssign:
aop = llvm::AtomicRMWInst::And;
break;
case BO_XorAssign:
aop = llvm::AtomicRMWInst::Xor;
break;
case BO_OrAssign:
aop = llvm::AtomicRMWInst::Or;
break;
default:
llvm_unreachable("Invalid compound assignment type");
}
if (aop != llvm::AtomicRMWInst::BAD_BINOP) {
llvm::Value *amt = CGF.EmitToMemory(
EmitScalarConversion(OpInfo.RHS, E->getRHS()->getType(), LHSTy,
E->getExprLoc()),
LHSTy);
Builder.CreateAtomicRMW(aop, LHSLV.getPointer(), amt,
llvm::SequentiallyConsistent);
return LHSLV;
}
}
// FIXME: For floating point types, we should be saving and restoring the
// floating point environment in the loop.
llvm::BasicBlock *startBB = Builder.GetInsertBlock();
llvm::BasicBlock *opBB = CGF.createBasicBlock("atomic_op", CGF.CurFn);
OpInfo.LHS = EmitLoadOfLValue(LHSLV, E->getExprLoc());
OpInfo.LHS = CGF.EmitToMemory(OpInfo.LHS, type);
Builder.CreateBr(opBB);
Builder.SetInsertPoint(opBB);
atomicPHI = Builder.CreatePHI(OpInfo.LHS->getType(), 2);
atomicPHI->addIncoming(OpInfo.LHS, startBB);
OpInfo.LHS = atomicPHI;
}
else
OpInfo.LHS = EmitLoadOfLValue(LHSLV, E->getExprLoc());
SourceLocation Loc = E->getExprLoc();
OpInfo.LHS =
EmitScalarConversion(OpInfo.LHS, LHSTy, E->getComputationLHSType(), Loc);
// Expand the binary operator.
Result = (this->*Func)(OpInfo);
// Convert the result back to the LHS type.
Result =
EmitScalarConversion(Result, E->getComputationResultType(), LHSTy, Loc);
if (atomicPHI) {
llvm::BasicBlock *opBB = Builder.GetInsertBlock();
llvm::BasicBlock *contBB = CGF.createBasicBlock("atomic_cont", CGF.CurFn);
auto Pair = CGF.EmitAtomicCompareExchange(
LHSLV, RValue::get(atomicPHI), RValue::get(Result), E->getExprLoc());
llvm::Value *old = CGF.EmitToMemory(Pair.first.getScalarVal(), LHSTy);
llvm::Value *success = Pair.second;
atomicPHI->addIncoming(old, opBB);
Builder.CreateCondBr(success, contBB, opBB);
Builder.SetInsertPoint(contBB);
return LHSLV;
}
// Store the result value into the LHS lvalue. Bit-fields are handled
// specially because the result is altered by the store, i.e., [C99 6.5.16p1]
// 'An assignment expression has the value of the left operand after the
// assignment...'.
if (LHSLV.isBitField())
CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, &Result);
else
CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV);
return LHSLV;
}
Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E,
Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) {
bool Ignore = TestAndClearIgnoreResultAssign();
Value *RHS;
LValue LHS = EmitCompoundAssignLValue(E, Func, RHS);
// If the result is clearly ignored, return now.
if (Ignore)
return nullptr;
// The result of an assignment in C is the assigned r-value.
if (!CGF.getLangOpts().CPlusPlus)
return RHS;
// If the lvalue is non-volatile, return the computed value of the assignment.
if (!LHS.isVolatileQualified())
return RHS;
// Otherwise, reload the value.
return EmitLoadOfLValue(LHS, E->getExprLoc());
}
void ScalarExprEmitter::EmitUndefinedBehaviorIntegerDivAndRemCheck(
const BinOpInfo &Ops, llvm::Value *Zero, bool isDiv) {
SmallVector<std::pair<llvm::Value *, SanitizerMask>, 2> Checks;
if (CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero)) {
Checks.push_back(std::make_pair(Builder.CreateICmpNE(Ops.RHS, Zero),
SanitizerKind::IntegerDivideByZero));
}
if (CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow) &&
Ops.Ty->hasSignedIntegerRepresentation()) {
llvm::IntegerType *Ty = cast<llvm::IntegerType>(Zero->getType());
llvm::Value *IntMin =
Builder.getInt(llvm::APInt::getSignedMinValue(Ty->getBitWidth()));
llvm::Value *NegOne = llvm::ConstantInt::get(Ty, -1ULL);
llvm::Value *LHSCmp = Builder.CreateICmpNE(Ops.LHS, IntMin);
llvm::Value *RHSCmp = Builder.CreateICmpNE(Ops.RHS, NegOne);
llvm::Value *NotOverflow = Builder.CreateOr(LHSCmp, RHSCmp, "or");
Checks.push_back(
std::make_pair(NotOverflow, SanitizerKind::SignedIntegerOverflow));
}
if (Checks.size() > 0)
EmitBinOpCheck(Checks, Ops);
}
Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) {
{
CodeGenFunction::SanitizerScope SanScope(&CGF);
if ((CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero) ||
CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow)) &&
Ops.Ty->isIntegerType()) {
llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, true);
} else if (CGF.SanOpts.has(SanitizerKind::FloatDivideByZero) &&
Ops.Ty->isRealFloatingType()) {
llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
llvm::Value *NonZero = Builder.CreateFCmpUNE(Ops.RHS, Zero);
EmitBinOpCheck(std::make_pair(NonZero, SanitizerKind::FloatDivideByZero),
Ops);
}
}
if (Ops.LHS->getType()->isFPOrFPVectorTy()) {
llvm::Value *Val = Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div");
if (CGF.getLangOpts().OpenCL) {
// OpenCL 1.1 7.4: minimum accuracy of single precision / is 2.5ulp
llvm::Type *ValTy = Val->getType();
if (ValTy->isFloatTy() ||
(isa<llvm::VectorType>(ValTy) &&
cast<llvm::VectorType>(ValTy)->getElementType()->isFloatTy()))
CGF.SetFPAccuracy(Val, 2.5);
}
return Val;
}
else if (Ops.Ty->hasUnsignedIntegerRepresentation())
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 (CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero)) {
CodeGenFunction::SanitizerScope SanScope(&CGF);
llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
if (Ops.Ty->isIntegerType())
EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, false);
}
if (Ops.Ty->hasUnsignedIntegerRepresentation())
return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem");
else
return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem");
}
Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) {
unsigned IID;
unsigned OpID = 0;
bool isSigned = Ops.Ty->isSignedIntegerOrEnumerationType();
switch (Ops.Opcode) {
case BO_Add:
case BO_AddAssign:
OpID = 1;
IID = isSigned ? llvm::Intrinsic::sadd_with_overflow :
llvm::Intrinsic::uadd_with_ov