diff options
Diffstat (limited to 'lib/VMCore/ConstantFold.cpp')
| -rw-r--r-- | lib/VMCore/ConstantFold.cpp | 1096 |
1 files changed, 658 insertions, 438 deletions
diff --git a/lib/VMCore/ConstantFold.cpp b/lib/VMCore/ConstantFold.cpp index 3aab0cc..c1fcc5f 100644 --- a/lib/VMCore/ConstantFold.cpp +++ b/lib/VMCore/ConstantFold.cpp @@ -12,9 +12,8 @@ // ConstantExpr::get* methods to automatically fold constants when possible. // // The current constant folding implementation is implemented in two pieces: the -// template-based folder for simple primitive constants like ConstantInt, and -// the special case hackery that we use to symbolically evaluate expressions -// that use ConstantExprs. +// pieces that don't need TargetData, and the pieces that do. This is to avoid +// a dependence in VMCore on Target. // //===----------------------------------------------------------------------===// @@ -24,8 +23,11 @@ #include "llvm/DerivedTypes.h" #include "llvm/Function.h" #include "llvm/GlobalAlias.h" +#include "llvm/GlobalVariable.h" +#include "llvm/LLVMContext.h" #include "llvm/ADT/SmallVector.h" #include "llvm/Support/Compiler.h" +#include "llvm/Support/ErrorHandling.h" #include "llvm/Support/GetElementPtrTypeIterator.h" #include "llvm/Support/ManagedStatic.h" #include "llvm/Support/MathExtras.h" @@ -39,7 +41,7 @@ using namespace llvm; /// BitCastConstantVector - Convert the specified ConstantVector node to the /// specified vector type. At this point, we know that the elements of the /// input vector constant are all simple integer or FP values. -static Constant *BitCastConstantVector(ConstantVector *CV, +static Constant *BitCastConstantVector(LLVMContext &Context, ConstantVector *CV, const VectorType *DstTy) { // If this cast changes element count then we can't handle it here: // doing so requires endianness information. This should be handled by @@ -47,7 +49,7 @@ static Constant *BitCastConstantVector(ConstantVector *CV, unsigned NumElts = DstTy->getNumElements(); if (NumElts != CV->getNumOperands()) return 0; - + // Check to verify that all elements of the input are simple. for (unsigned i = 0; i != NumElts; ++i) { if (!isa<ConstantInt>(CV->getOperand(i)) && @@ -59,7 +61,8 @@ static Constant *BitCastConstantVector(ConstantVector *CV, std::vector<Constant*> Result; const Type *DstEltTy = DstTy->getElementType(); for (unsigned i = 0; i != NumElts; ++i) - Result.push_back(ConstantExpr::getBitCast(CV->getOperand(i), DstEltTy)); + Result.push_back(ConstantExpr::getBitCast(CV->getOperand(i), + DstEltTy)); return ConstantVector::get(Result); } @@ -70,13 +73,13 @@ static Constant *BitCastConstantVector(ConstantVector *CV, static unsigned foldConstantCastPair( unsigned opc, ///< opcode of the second cast constant expression - const ConstantExpr*Op, ///< the first cast constant expression + ConstantExpr *Op, ///< the first cast constant expression const Type *DstTy ///< desintation type of the first cast ) { assert(Op && Op->isCast() && "Can't fold cast of cast without a cast!"); assert(DstTy && DstTy->isFirstClassType() && "Invalid cast destination type"); assert(CastInst::isCast(opc) && "Invalid cast opcode"); - + // The the types and opcodes for the two Cast constant expressions const Type *SrcTy = Op->getOperand(0)->getType(); const Type *MidTy = Op->getType(); @@ -85,41 +88,45 @@ foldConstantCastPair( // Let CastInst::isEliminableCastPair do the heavy lifting. return CastInst::isEliminableCastPair(firstOp, secondOp, SrcTy, MidTy, DstTy, - Type::Int64Ty); + Type::getInt64Ty(DstTy->getContext())); } -static Constant *FoldBitCast(Constant *V, const Type *DestTy) { +static Constant *FoldBitCast(LLVMContext &Context, + Constant *V, const Type *DestTy) { const Type *SrcTy = V->getType(); if (SrcTy == DestTy) return V; // no-op cast - + // Check to see if we are casting a pointer to an aggregate to a pointer to // the first element. If so, return the appropriate GEP instruction. if (const PointerType *PTy = dyn_cast<PointerType>(V->getType())) if (const PointerType *DPTy = dyn_cast<PointerType>(DestTy)) if (PTy->getAddressSpace() == DPTy->getAddressSpace()) { SmallVector<Value*, 8> IdxList; - IdxList.push_back(Constant::getNullValue(Type::Int32Ty)); + Value *Zero = Constant::getNullValue(Type::getInt32Ty(Context)); + IdxList.push_back(Zero); const Type *ElTy = PTy->getElementType(); while (ElTy != DPTy->getElementType()) { if (const StructType *STy = dyn_cast<StructType>(ElTy)) { if (STy->getNumElements() == 0) break; ElTy = STy->getElementType(0); - IdxList.push_back(Constant::getNullValue(Type::Int32Ty)); + IdxList.push_back(Zero); } else if (const SequentialType *STy = dyn_cast<SequentialType>(ElTy)) { if (isa<PointerType>(ElTy)) break; // Can't index into pointers! ElTy = STy->getElementType(); - IdxList.push_back(IdxList[0]); + IdxList.push_back(Zero); } else { break; } } - + if (ElTy == DPTy->getElementType()) - return ConstantExpr::getGetElementPtr(V, &IdxList[0], IdxList.size()); + // This GEP is inbounds because all indices are zero. + return ConstantExpr::getInBoundsGetElementPtr(V, &IdxList[0], + IdxList.size()); } - + // Handle casts from one vector constant to another. We know that the src // and dest type have the same size (otherwise its an illegal cast). if (const VectorType *DestPTy = dyn_cast<VectorType>(DestTy)) { @@ -130,48 +137,50 @@ static Constant *FoldBitCast(Constant *V, const Type *DestTy) { // First, check for null. Undef is already handled. if (isa<ConstantAggregateZero>(V)) return Constant::getNullValue(DestTy); - + if (ConstantVector *CV = dyn_cast<ConstantVector>(V)) - return BitCastConstantVector(CV, DestPTy); + return BitCastConstantVector(Context, CV, DestPTy); } // Canonicalize scalar-to-vector bitcasts into vector-to-vector bitcasts // This allows for other simplifications (although some of them // can only be handled by Analysis/ConstantFolding.cpp). if (isa<ConstantInt>(V) || isa<ConstantFP>(V)) - return ConstantExpr::getBitCast(ConstantVector::get(&V, 1), DestPTy); + return ConstantExpr::getBitCast( + ConstantVector::get(&V, 1), DestPTy); } - + // Finally, implement bitcast folding now. The code below doesn't handle // bitcast right. if (isa<ConstantPointerNull>(V)) // ptr->ptr cast. return ConstantPointerNull::get(cast<PointerType>(DestTy)); - + // Handle integral constant input. - if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) { + if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) { if (DestTy->isInteger()) // Integral -> Integral. This is a no-op because the bit widths must // be the same. Consequently, we just fold to V. return V; if (DestTy->isFloatingPoint()) - return ConstantFP::get(APFloat(CI->getValue(), - DestTy != Type::PPC_FP128Ty)); + return ConstantFP::get(Context, APFloat(CI->getValue(), + DestTy != Type::getPPC_FP128Ty(Context))); // Otherwise, can't fold this (vector?) return 0; } // Handle ConstantFP input. - if (const ConstantFP *FP = dyn_cast<ConstantFP>(V)) + if (ConstantFP *FP = dyn_cast<ConstantFP>(V)) // FP -> Integral. - return ConstantInt::get(FP->getValueAPF().bitcastToAPInt()); + return ConstantInt::get(Context, FP->getValueAPF().bitcastToAPInt()); return 0; } -Constant *llvm::ConstantFoldCastInstruction(unsigned opc, const Constant *V, +Constant *llvm::ConstantFoldCastInstruction(LLVMContext &Context, + unsigned opc, Constant *V, const Type *DestTy) { if (isa<UndefValue>(V)) { // zext(undef) = 0, because the top bits will be zero. @@ -183,12 +192,12 @@ Constant *llvm::ConstantFoldCastInstruction(unsigned opc, const Constant *V, return UndefValue::get(DestTy); } // No compile-time operations on this type yet. - if (V->getType() == Type::PPC_FP128Ty || DestTy == Type::PPC_FP128Ty) + if (V->getType()->isPPC_FP128Ty() || DestTy->isPPC_FP128Ty()) return 0; // If the cast operand is a constant expression, there's a few things we can // do to try to simplify it. - if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) { + if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) { if (CE->isCast()) { // Try hard to fold cast of cast because they are often eliminable. if (unsigned newOpc = foldConstantCastPair(opc, CE, DestTy)) @@ -211,7 +220,7 @@ Constant *llvm::ConstantFoldCastInstruction(unsigned opc, const Constant *V, // If the cast operand is a constant vector, perform the cast by // operating on each element. In the cast of bitcasts, the element // count may be mismatched; don't attempt to handle that here. - if (const ConstantVector *CV = dyn_cast<ConstantVector>(V)) + if (ConstantVector *CV = dyn_cast<ConstantVector>(V)) if (isa<VectorType>(DestTy) && cast<VectorType>(DestTy)->getNumElements() == CV->getType()->getNumElements()) { @@ -229,21 +238,21 @@ Constant *llvm::ConstantFoldCastInstruction(unsigned opc, const Constant *V, switch (opc) { case Instruction::FPTrunc: case Instruction::FPExt: - if (const ConstantFP *FPC = dyn_cast<ConstantFP>(V)) { + if (ConstantFP *FPC = dyn_cast<ConstantFP>(V)) { bool ignored; APFloat Val = FPC->getValueAPF(); - Val.convert(DestTy == Type::FloatTy ? APFloat::IEEEsingle : - DestTy == Type::DoubleTy ? APFloat::IEEEdouble : - DestTy == Type::X86_FP80Ty ? APFloat::x87DoubleExtended : - DestTy == Type::FP128Ty ? APFloat::IEEEquad : + Val.convert(DestTy->isFloatTy() ? APFloat::IEEEsingle : + DestTy->isDoubleTy() ? APFloat::IEEEdouble : + DestTy->isX86_FP80Ty() ? APFloat::x87DoubleExtended : + DestTy->isFP128Ty() ? APFloat::IEEEquad : APFloat::Bogus, APFloat::rmNearestTiesToEven, &ignored); - return ConstantFP::get(Val); + return ConstantFP::get(Context, Val); } return 0; // Can't fold. case Instruction::FPToUI: case Instruction::FPToSI: - if (const ConstantFP *FPC = dyn_cast<ConstantFP>(V)) { + if (ConstantFP *FPC = dyn_cast<ConstantFP>(V)) { const APFloat &V = FPC->getValueAPF(); bool ignored; uint64_t x[2]; @@ -251,7 +260,7 @@ Constant *llvm::ConstantFoldCastInstruction(unsigned opc, const Constant *V, (void) V.convertToInteger(x, DestBitWidth, opc==Instruction::FPToSI, APFloat::rmTowardZero, &ignored); APInt Val(DestBitWidth, 2, x); - return ConstantInt::get(Val); + return ConstantInt::get(Context, Val); } return 0; // Can't fold. case Instruction::IntToPtr: //always treated as unsigned @@ -264,7 +273,7 @@ Constant *llvm::ConstantFoldCastInstruction(unsigned opc, const Constant *V, return 0; // Other pointer types cannot be casted case Instruction::UIToFP: case Instruction::SIToFP: - if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) { + if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) { APInt api = CI->getValue(); const uint64_t zero[] = {0, 0}; APFloat apf = APFloat(APInt(DestTy->getPrimitiveSizeInBits(), @@ -272,67 +281,68 @@ Constant *llvm::ConstantFoldCastInstruction(unsigned opc, const Constant *V, (void)apf.convertFromAPInt(api, opc==Instruction::SIToFP, APFloat::rmNearestTiesToEven); - return ConstantFP::get(apf); + return ConstantFP::get(Context, apf); } return 0; case Instruction::ZExt: - if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) { + if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) { uint32_t BitWidth = cast<IntegerType>(DestTy)->getBitWidth(); APInt Result(CI->getValue()); Result.zext(BitWidth); - return ConstantInt::get(Result); + return ConstantInt::get(Context, Result); } return 0; case Instruction::SExt: - if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) { + if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) { uint32_t BitWidth = cast<IntegerType>(DestTy)->getBitWidth(); APInt Result(CI->getValue()); Result.sext(BitWidth); - return ConstantInt::get(Result); + return ConstantInt::get(Context, Result); } return 0; case Instruction::Trunc: - if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) { + if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) { uint32_t BitWidth = cast<IntegerType>(DestTy)->getBitWidth(); APInt Result(CI->getValue()); Result.trunc(BitWidth); - return ConstantInt::get(Result); + return ConstantInt::get(Context, Result); } return 0; case Instruction::BitCast: - return FoldBitCast(const_cast<Constant*>(V), DestTy); + return FoldBitCast(Context, V, DestTy); default: assert(!"Invalid CE CastInst opcode"); break; } - assert(0 && "Failed to cast constant expression"); + llvm_unreachable("Failed to cast constant expression"); return 0; } -Constant *llvm::ConstantFoldSelectInstruction(const Constant *Cond, - const Constant *V1, - const Constant *V2) { - if (const ConstantInt *CB = dyn_cast<ConstantInt>(Cond)) - return const_cast<Constant*>(CB->getZExtValue() ? V1 : V2); +Constant *llvm::ConstantFoldSelectInstruction(LLVMContext&, + Constant *Cond, + Constant *V1, Constant *V2) { + if (ConstantInt *CB = dyn_cast<ConstantInt>(Cond)) + return CB->getZExtValue() ? V1 : V2; - if (isa<UndefValue>(V1)) return const_cast<Constant*>(V2); - if (isa<UndefValue>(V2)) return const_cast<Constant*>(V1); - if (isa<UndefValue>(Cond)) return const_cast<Constant*>(V1); - if (V1 == V2) return const_cast<Constant*>(V1); + if (isa<UndefValue>(V1)) return V2; + if (isa<UndefValue>(V2)) return V1; + if (isa<UndefValue>(Cond)) return V1; + if (V1 == V2) return V1; return 0; } -Constant *llvm::ConstantFoldExtractElementInstruction(const Constant *Val, - const Constant *Idx) { +Constant *llvm::ConstantFoldExtractElementInstruction(LLVMContext &Context, + Constant *Val, + Constant *Idx) { if (isa<UndefValue>(Val)) // ee(undef, x) -> undef return UndefValue::get(cast<VectorType>(Val->getType())->getElementType()); if (Val->isNullValue()) // ee(zero, x) -> zero return Constant::getNullValue( cast<VectorType>(Val->getType())->getElementType()); - - if (const ConstantVector *CVal = dyn_cast<ConstantVector>(Val)) { - if (const ConstantInt *CIdx = dyn_cast<ConstantInt>(Idx)) { + + if (ConstantVector *CVal = dyn_cast<ConstantVector>(Val)) { + if (ConstantInt *CIdx = dyn_cast<ConstantInt>(Idx)) { return CVal->getOperand(CIdx->getZExtValue()); } else if (isa<UndefValue>(Idx)) { // ee({w,x,y,z}, undef) -> w (an arbitrary value). @@ -342,17 +352,18 @@ Constant *llvm::ConstantFoldExtractElementInstruction(const Constant *Val, return 0; } -Constant *llvm::ConstantFoldInsertElementInstruction(const Constant *Val, - const Constant *Elt, - const Constant *Idx) { - const ConstantInt *CIdx = dyn_cast<ConstantInt>(Idx); +Constant *llvm::ConstantFoldInsertElementInstruction(LLVMContext &Context, + Constant *Val, + Constant *Elt, + Constant *Idx) { + ConstantInt *CIdx = dyn_cast<ConstantInt>(Idx); if (!CIdx) return 0; APInt idxVal = CIdx->getValue(); if (isa<UndefValue>(Val)) { // Insertion of scalar constant into vector undef // Optimize away insertion of undef if (isa<UndefValue>(Elt)) - return const_cast<Constant*>(Val); + return Val; // Otherwise break the aggregate undef into multiple undefs and do // the insertion unsigned numOps = @@ -360,9 +371,9 @@ Constant *llvm::ConstantFoldInsertElementInstruction(const Constant *Val, std::vector<Constant*> Ops; Ops.reserve(numOps); for (unsigned i = 0; i < numOps; ++i) { - const Constant *Op = + Constant *Op = (idxVal == i) ? Elt : UndefValue::get(Elt->getType()); - Ops.push_back(const_cast<Constant*>(Op)); + Ops.push_back(Op); } return ConstantVector::get(Ops); } @@ -370,7 +381,7 @@ Constant *llvm::ConstantFoldInsertElementInstruction(const Constant *Val, // Insertion of scalar constant into vector aggregate zero // Optimize away insertion of zero if (Elt->isNullValue()) - return const_cast<Constant*>(Val); + return Val; // Otherwise break the aggregate zero into multiple zeros and do // the insertion unsigned numOps = @@ -378,20 +389,20 @@ Constant *llvm::ConstantFoldInsertElementInstruction(const Constant *Val, std::vector<Constant*> Ops; Ops.reserve(numOps); for (unsigned i = 0; i < numOps; ++i) { - const Constant *Op = + Constant *Op = (idxVal == i) ? Elt : Constant::getNullValue(Elt->getType()); - Ops.push_back(const_cast<Constant*>(Op)); + Ops.push_back(Op); } return ConstantVector::get(Ops); } - if (const ConstantVector *CVal = dyn_cast<ConstantVector>(Val)) { + if (ConstantVector *CVal = dyn_cast<ConstantVector>(Val)) { // Insertion of scalar constant into vector constant std::vector<Constant*> Ops; Ops.reserve(CVal->getNumOperands()); for (unsigned i = 0; i < CVal->getNumOperands(); ++i) { - const Constant *Op = + Constant *Op = (idxVal == i) ? Elt : cast<Constant>(CVal->getOperand(i)); - Ops.push_back(const_cast<Constant*>(Op)); + Ops.push_back(Op); } return ConstantVector::get(Ops); } @@ -401,10 +412,11 @@ Constant *llvm::ConstantFoldInsertElementInstruction(const Constant *Val, /// GetVectorElement - If C is a ConstantVector, ConstantAggregateZero or Undef /// return the specified element value. Otherwise return null. -static Constant *GetVectorElement(const Constant *C, unsigned EltNo) { - if (const ConstantVector *CV = dyn_cast<ConstantVector>(C)) +static Constant *GetVectorElement(LLVMContext &Context, Constant *C, + unsigned EltNo) { + if (ConstantVector *CV = dyn_cast<ConstantVector>(C)) return CV->getOperand(EltNo); - + const Type *EltTy = cast<VectorType>(C->getType())->getElementType(); if (isa<ConstantAggregateZero>(C)) return Constant::getNullValue(EltTy); @@ -413,9 +425,10 @@ static Constant *GetVectorElement(const Constant *C, unsigned EltNo) { return 0; } -Constant *llvm::ConstantFoldShuffleVectorInstruction(const Constant *V1, - const Constant *V2, - const Constant *Mask) { +Constant *llvm::ConstantFoldShuffleVectorInstruction(LLVMContext &Context, + Constant *V1, + Constant *V2, + Constant *Mask) { // Undefined shuffle mask -> undefined value. if (isa<UndefValue>(Mask)) return UndefValue::get(V1->getType()); @@ -426,7 +439,7 @@ Constant *llvm::ConstantFoldShuffleVectorInstruction(const Constant *V1, // Loop over the shuffle mask, evaluating each element. SmallVector<Constant*, 32> Result; for (unsigned i = 0; i != MaskNumElts; ++i) { - Constant *InElt = GetVectorElement(Mask, i); + Constant *InElt = GetVectorElement(Context, Mask, i); if (InElt == 0) return 0; if (isa<UndefValue>(InElt)) @@ -436,9 +449,9 @@ Constant *llvm::ConstantFoldShuffleVectorInstruction(const Constant *V1, if (Elt >= SrcNumElts*2) InElt = UndefValue::get(EltTy); else if (Elt >= SrcNumElts) - InElt = GetVectorElement(V2, Elt - SrcNumElts); + InElt = GetVectorElement(Context, V2, Elt - SrcNumElts); else - InElt = GetVectorElement(V1, Elt); + InElt = GetVectorElement(Context, V1, Elt); if (InElt == 0) return 0; } else { // Unknown value. @@ -450,12 +463,13 @@ Constant *llvm::ConstantFoldShuffleVectorInstruction(const Constant *V1, return ConstantVector::get(&Result[0], Result.size()); } -Constant *llvm::ConstantFoldExtractValueInstruction(const Constant *Agg, +Constant *llvm::ConstantFoldExtractValueInstruction(LLVMContext &Context, + Constant *Agg, const unsigned *Idxs, unsigned NumIdx) { // Base case: no indices, so return the entire value. if (NumIdx == 0) - return const_cast<Constant *>(Agg); + return Agg; if (isa<UndefValue>(Agg)) // ev(undef, x) -> undef return UndefValue::get(ExtractValueInst::getIndexedType(Agg->getType(), @@ -469,123 +483,111 @@ Constant *llvm::ConstantFoldExtractValueInstruction(const Constant *Agg, Idxs + NumIdx)); // Otherwise recurse. - return ConstantFoldExtractValueInstruction(Agg->getOperand(*Idxs), + return ConstantFoldExtractValueInstruction(Context, Agg->getOperand(*Idxs), Idxs+1, NumIdx-1); } -Constant *llvm::ConstantFoldInsertValueInstruction(const Constant *Agg, - const Constant *Val, +Constant *llvm::ConstantFoldInsertValueInstruction(LLVMContext &Context, + Constant *Agg, + Constant *Val, const unsigned *Idxs, unsigned NumIdx) { // Base case: no indices, so replace the entire value. if (NumIdx == 0) - return const_cast<Constant *>(Val); + return Val; if (isa<UndefValue>(Agg)) { // Insertion of constant into aggregate undef - // Optimize away insertion of undef + // Optimize away insertion of undef. if (isa<UndefValue>(Val)) - return const_cast<Constant*>(Agg); + return Agg; + // Otherwise break the aggregate undef into multiple undefs and do - // the insertion + // the insertion. const CompositeType *AggTy = cast<CompositeType>(Agg->getType()); unsigned numOps; if (const ArrayType *AR = dyn_cast<ArrayType>(AggTy)) numOps = AR->getNumElements(); else numOps = cast<StructType>(AggTy)->getNumElements(); + std::vector<Constant*> Ops(numOps); for (unsigned i = 0; i < numOps; ++i) { const Type *MemberTy = AggTy->getTypeAtIndex(i); - const Constant *Op = + Constant *Op = (*Idxs == i) ? - ConstantFoldInsertValueInstruction(UndefValue::get(MemberTy), + ConstantFoldInsertValueInstruction(Context, UndefValue::get(MemberTy), Val, Idxs+1, NumIdx-1) : UndefValue::get(MemberTy); - Ops[i] = const_cast<Constant*>(Op); + Ops[i] = Op; } - if (isa<StructType>(AggTy)) - return ConstantStruct::get(Ops); - else - return ConstantArray::get(cast<ArrayType>(AggTy), Ops); + + if (const StructType* ST = dyn_cast<StructType>(AggTy)) + return ConstantStruct::get(Context, Ops, ST->isPacked()); + return ConstantArray::get(cast<ArrayType>(AggTy), Ops); } + if (isa<ConstantAggregateZero>(Agg)) { // Insertion of constant into aggregate zero - // Optimize away insertion of zero + // Optimize away insertion of zero. if (Val->isNullValue()) - return const_cast<Constant*>(Agg); + return Agg; + // Otherwise break the aggregate zero into multiple zeros and do - // the insertion + // the insertion. const CompositeType *AggTy = cast<CompositeType>(Agg->getType()); unsigned numOps; if (const ArrayType *AR = dyn_cast<ArrayType>(AggTy)) numOps = AR->getNumElements(); else numOps = cast<StructType>(AggTy)->getNumElements(); + std::vector<Constant*> Ops(numOps); for (unsigned i = 0; i < numOps; ++i) { const Type *MemberTy = AggTy->getTypeAtIndex(i); - const Constant *Op = + Constant *Op = (*Idxs == i) ? - ConstantFoldInsertValueInstruction(Constant::getNullValue(MemberTy), + ConstantFoldInsertValueInstruction(Context, + Constant::getNullValue(MemberTy), Val, Idxs+1, NumIdx-1) : Constant::getNullValue(MemberTy); - Ops[i] = const_cast<Constant*>(Op); + Ops[i] = Op; } - if (isa<StructType>(AggTy)) - return ConstantStruct::get(Ops); - else - return ConstantArray::get(cast<ArrayType>(AggTy), Ops); + + if (const StructType* ST = dyn_cast<StructType>(AggTy)) + return ConstantStruct::get(Context, Ops, ST->isPacked()); + return ConstantArray::get(cast<ArrayType>(AggTy), Ops); } + if (isa<ConstantStruct>(Agg) || isa<ConstantArray>(Agg)) { - // Insertion of constant into aggregate constant + // Insertion of constant into aggregate constant. std::vector<Constant*> Ops(Agg->getNumOperands()); for (unsigned i = 0; i < Agg->getNumOperands(); ++i) { - const Constant *Op = + Constant *Op = (*Idxs == i) ? - ConstantFoldInsertValueInstruction(Agg->getOperand(i), + ConstantFoldInsertValueInstruction(Context, Agg->getOperand(i), Val, Idxs+1, NumIdx-1) : Agg->getOperand(i); - Ops[i] = const_cast<Constant*>(Op); + Ops[i] = Op; } - Constant *C; - if (isa<StructType>(Agg->getType())) - C = ConstantStruct::get(Ops); - else - C = ConstantArray::get(cast<ArrayType>(Agg->getType()), Ops); - return C; + + if (const StructType* ST = dyn_cast<StructType>(Agg->getType())) + return ConstantStruct::get(Context, Ops, ST->isPacked()); + return ConstantArray::get(cast<ArrayType>(Agg->getType()), Ops); } return 0; } -/// EvalVectorOp - Given two vector constants and a function pointer, apply the -/// function pointer to each element pair, producing a new ConstantVector -/// constant. Either or both of V1 and V2 may be NULL, meaning a -/// ConstantAggregateZero operand. -static Constant *EvalVectorOp(const ConstantVector *V1, - const ConstantVector *V2, - const VectorType *VTy, - Constant *(*FP)(Constant*, Constant*)) { - std::vector<Constant*> Res; - const Type *EltTy = VTy->getElementType(); - for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { - const Constant *C1 = V1 ? V1->getOperand(i) : Constant::getNullValue(EltTy); - const Constant *C2 = V2 ? V2->getOperand(i) : Constant::getNullValue(EltTy); - Res.push_back(FP(const_cast<Constant*>(C1), - const_cast<Constant*>(C2))); - } - return ConstantVector::get(Res); -} -Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, - const Constant *C1, - const Constant *C2) { +Constant *llvm::ConstantFoldBinaryInstruction(LLVMContext &Context, + unsigned Opcode, + Constant *C1, Constant *C2) { // No compile-time operations on this type yet. - if (C1->getType() == Type::PPC_FP128Ty) + if (C1->getType()->isPPC_FP128Ty()) return 0; - // Handle UndefValue up front + // Handle UndefValue up front. if (isa<UndefValue>(C1) || isa<UndefValue>(C2)) { switch (Opcode) { case Instruction::Xor: @@ -606,23 +608,23 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, case Instruction::SRem: if (!isa<UndefValue>(C2)) // undef / X -> 0 return Constant::getNullValue(C1->getType()); - return const_cast<Constant*>(C2); // X / undef -> undef + return C2; // X / undef -> undef case Instruction::Or: // X | undef -> -1 if (const VectorType *PTy = dyn_cast<VectorType>(C1->getType())) - return ConstantVector::getAllOnesValue(PTy); - return ConstantInt::getAllOnesValue(C1->getType()); + return Constant::getAllOnesValue(PTy); + return Constant::getAllOnesValue(C1->getType()); case Instruction::LShr: if (isa<UndefValue>(C2) && isa<UndefValue>(C1)) - return const_cast<Constant*>(C1); // undef lshr undef -> undef + return C1; // undef lshr undef -> undef return Constant::getNullValue(C1->getType()); // X lshr undef -> 0 // undef lshr X -> 0 case Instruction::AShr: if (!isa<UndefValue>(C2)) - return const_cast<Constant*>(C1); // undef ashr X --> undef + return C1; // undef ashr X --> undef else if (isa<UndefValue>(C1)) - return const_cast<Constant*>(C1); // undef ashr undef -> undef + return C1; // undef ashr undef -> undef else - return const_cast<Constant*>(C1); // X ashr undef --> X + return C1; // X ashr undef --> X case Instruction::Shl: // undef << X -> 0 or X << undef -> 0 return Constant::getNullValue(C1->getType()); @@ -630,23 +632,23 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, } // Handle simplifications when the RHS is a constant int. - if (const ConstantInt *CI2 = dyn_cast<ConstantInt>(C2)) { + if (ConstantInt *CI2 = dyn_cast<ConstantInt>(C2)) { switch (Opcode) { case Instruction::Add: - if (CI2->equalsInt(0)) return const_cast<Constant*>(C1); // X + 0 == X + if (CI2->equalsInt(0)) return C1; // X + 0 == X break; case Instruction::Sub: - if (CI2->equalsInt(0)) return const_cast<Constant*>(C1); // X - 0 == X + if (CI2->equalsInt(0)) return C1; // X - 0 == X break; case Instruction::Mul: - if (CI2->equalsInt(0)) return const_cast<Constant*>(C2); // X * 0 == 0 + if (CI2->equalsInt(0)) return C2; // X * 0 == 0 if (CI2->equalsInt(1)) - return const_cast<Constant*>(C1); // X * 1 == X + return C1; // X * 1 == X break; case Instruction::UDiv: case Instruction::SDiv: if (CI2->equalsInt(1)) - return const_cast<Constant*>(C1); // X / 1 == X + return C1; // X / 1 == X if (CI2->equalsInt(0)) return UndefValue::get(CI2->getType()); // X / 0 == undef break; @@ -658,11 +660,11 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, return UndefValue::get(CI2->getType()); // X % 0 == undef break; case Instruction::And: - if (CI2->isZero()) return const_cast<Constant*>(C2); // X & 0 == 0 + if (CI2->isZero()) return C2; // X & 0 == 0 if (CI2->isAllOnesValue()) - return const_cast<Constant*>(C1); // X & -1 == X - - if (const ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) { + return C1; // X & -1 == X + + if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) { // (zext i32 to i64) & 4294967295 -> (zext i32 to i64) if (CE1->getOpcode() == Instruction::ZExt) { unsigned DstWidth = CI2->getType()->getBitWidth(); @@ -670,19 +672,19 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, CE1->getOperand(0)->getType()->getPrimitiveSizeInBits(); APInt PossiblySetBits(APInt::getLowBitsSet(DstWidth, SrcWidth)); if ((PossiblySetBits & CI2->getValue()) == PossiblySetBits) - return const_cast<Constant*>(C1); + return C1; } - + // If and'ing the address of a global with a constant, fold it. if (CE1->getOpcode() == Instruction::PtrToInt && isa<GlobalValue>(CE1->getOperand(0))) { GlobalValue *GV = cast<GlobalValue>(CE1->getOperand(0)); - + // Functions are at least 4-byte aligned. unsigned GVAlign = GV->getAlignment(); if (isa<Function>(GV)) GVAlign = std::max(GVAlign, 4U); - + if (GVAlign > 1) { unsigned DstWidth = CI2->getType()->getBitWidth(); unsigned SrcWidth = std::min(DstWidth, Log2_32(GVAlign)); @@ -696,26 +698,39 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, } break; case Instruction::Or: - if (CI2->equalsInt(0)) return const_cast<Constant*>(C1); // X | 0 == X + if (CI2->equalsInt(0)) return C1; // X | 0 == X if (CI2->isAllOnesValue()) - return const_cast<Constant*>(C2); // X | -1 == -1 + return C2; // X | -1 == -1 break; case Instruction::Xor: - if (CI2->equalsInt(0)) return const_cast<Constant*>(C1); // X ^ 0 == X + if (CI2->equalsInt(0)) return C1; // X ^ 0 == X + + if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) { + switch (CE1->getOpcode()) { + default: break; + case Instruction::ICmp: + case Instruction::FCmp: + // cmp pred ^ true -> cmp !pred + assert(CI2->equalsInt(1)); + CmpInst::Predicate pred = (CmpInst::Predicate)CE1->getPredicate(); + pred = CmpInst::getInversePredicate(pred); + return ConstantExpr::getCompare(pred, CE1->getOperand(0), + CE1->getOperand(1)); + } + } break; case Instruction::AShr: // ashr (zext C to Ty), C2 -> lshr (zext C, CSA), C2 - if (const ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) + if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) if (CE1->getOpcode() == Instruction::ZExt) // Top bits known zero. - return ConstantExpr::getLShr(const_cast<Constant*>(C1), - const_cast<Constant*>(C2)); + return ConstantExpr::getLShr(C1, C2); break; } } - + // At this point we know neither constant is an UndefValue. - if (const ConstantInt *CI1 = dyn_cast<ConstantInt>(C1)) { - if (const ConstantInt *CI2 = dyn_cast<ConstantInt>(C2)) { + if (ConstantInt *CI1 = dyn_cast<ConstantInt>(C1)) { + if (ConstantInt *CI2 = dyn_cast<ConstantInt>(C2)) { using namespace APIntOps; const APInt &C1V = CI1->getValue(); const APInt &C2V = CI2->getValue(); @@ -723,51 +738,51 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, default: break; case Instruction::Add: - return ConstantInt::get(C1V + C2V); + return ConstantInt::get(Context, C1V + C2V); case Instruction::Sub: - return ConstantInt::get(C1V - C2V); + return ConstantInt::get(Context, C1V - C2V); case Instruction::Mul: - return ConstantInt::get(C1V * C2V); + return ConstantInt::get(Context, C1V * C2V); case Instruction::UDiv: assert(!CI2->isNullValue() && "Div by zero handled above"); - return ConstantInt::get(C1V.udiv(C2V)); + return ConstantInt::get(Context, C1V.udiv(C2V)); case Instruction::SDiv: assert(!CI2->isNullValue() && "Div by zero handled above"); if (C2V.isAllOnesValue() && C1V.isMinSignedValue()) return UndefValue::get(CI1->getType()); // MIN_INT / -1 -> undef - return ConstantInt::get(C1V.sdiv(C2V)); + return ConstantInt::get(Context, C1V.sdiv(C2V)); case Instruction::URem: assert(!CI2->isNullValue() && "Div by zero handled above"); - return ConstantInt::get(C1V.urem(C2V)); + return ConstantInt::get(Context, C1V.urem(C2V)); case Instruction::SRem: assert(!CI2->isNullValue() && "Div by zero handled above"); if (C2V.isAllOnesValue() && C1V.isMinSignedValue()) return UndefValue::get(CI1->getType()); // MIN_INT % -1 -> undef - return ConstantInt::get(C1V.srem(C2V)); + return ConstantInt::get(Context, C1V.srem(C2V)); case Instruction::And: - return ConstantInt::get(C1V & C2V); + return ConstantInt::get(Context, C1V & C2V); case Instruction::Or: - return ConstantInt::get(C1V | C2V); + return ConstantInt::get(Context, C1V | C2V); case Instruction::Xor: - return ConstantInt::get(C1V ^ C2V); + return ConstantInt::get(Context, C1V ^ C2V); case Instruction::Shl: { uint32_t shiftAmt = C2V.getZExtValue(); if (shiftAmt < C1V.getBitWidth()) - return ConstantInt::get(C1V.shl(shiftAmt)); + return ConstantInt::get(Context, C1V.shl(shiftAmt)); else return UndefValue::get(C1->getType()); // too big shift is undef } case Instruction::LShr: { uint32_t shiftAmt = C2V.getZExtValue(); if (shiftAmt < C1V.getBitWidth()) - return ConstantInt::get(C1V.lshr(shiftAmt)); + return ConstantInt::get(Context, C1V.lshr(shiftAmt)); else return UndefValue::get(C1->getType()); // too big shift is undef } case Instruction::AShr: { uint32_t shiftAmt = C2V.getZExtValue(); if (shiftAmt < C1V.getBitWidth()) - return ConstantInt::get(C1V.ashr(shiftAmt)); + return ConstantInt::get(Context, C1V.ashr(shiftAmt)); else return UndefValue::get(C1->getType()); // too big shift is undef } @@ -782,13 +797,13 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, case Instruction::LShr: case Instruction::AShr: case Instruction::Shl: - if (CI1->equalsInt(0)) return const_cast<Constant*>(C1); + if (CI1->equalsInt(0)) return C1; break; default: break; } - } else if (const ConstantFP *CFP1 = dyn_cast<ConstantFP>(C1)) { - if (const ConstantFP *CFP2 = dyn_cast<ConstantFP>(C2)) { + } else if (ConstantFP *CFP1 = dyn_cast<ConstantFP>(C1)) { + if (ConstantFP *CFP2 = dyn_cast<ConstantFP>(C2)) { APFloat C1V = CFP1->getValueAPF(); APFloat C2V = CFP2->getValueAPF(); APFloat C3V = C1V; // copy for modification @@ -797,65 +812,159 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, break; case Instruction::FAdd: (void)C3V.add(C2V, APFloat::rmNearestTiesToEven); - return ConstantFP::get(C3V); + return ConstantFP::get(Context, C3V); case Instruction::FSub: (void)C3V.subtract(C2V, APFloat::rmNearestTiesToEven); - return ConstantFP::get(C3V); + return ConstantFP::get(Context, C3V); case Instruction::FMul: (void)C3V.multiply(C2V, APFloat::rmNearestTiesToEven); - return ConstantFP::get(C3V); + return ConstantFP::get(Context, C3V); case Instruction::FDiv: (void)C3V.divide(C2V, APFloat::rmNearestTiesToEven); - return ConstantFP::get(C3V); + return ConstantFP::get(Context, C3V); case Instruction::FRem: (void)C3V.mod(C2V, APFloat::rmNearestTiesToEven); - return ConstantFP::get(C3V); + return ConstantFP::get(Context, C3V); } } } else if (const VectorType *VTy = dyn_cast<VectorType>(C1->getType())) { - const ConstantVector *CP1 = dyn_cast<ConstantVector>(C1); - const ConstantVector *CP2 = dyn_cast<ConstantVector>(C2); + ConstantVector *CP1 = dyn_cast<ConstantVector>(C1); + ConstantVector *CP2 = dyn_cast<ConstantVector>(C2); if ((CP1 != NULL || isa<ConstantAggregateZero>(C1)) && (CP2 != NULL || isa<ConstantAggregateZero>(C2))) { + std::vector<Constant*> Res; + const Type* EltTy = VTy->getElementType(); + Constant *C1 = 0; + Constant *C2 = 0; switch (Opcode) { default: break; case Instruction::Add: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getAdd); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getAdd(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::FAdd: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getFAdd); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getFAdd(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::Sub: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getSub); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getSub(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::FSub: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getFSub); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getFSub(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::Mul: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getMul); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getMul(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::FMul: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getFMul); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getFMul(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::UDiv: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getUDiv); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getUDiv(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::SDiv: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getSDiv); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getSDiv(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::FDiv: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getFDiv); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getFDiv(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::URem: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getURem); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getURem(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::SRem: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getSRem); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getSRem(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::FRem: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getFRem); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getFRem(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::And: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getAnd); - case Instruction::Or: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getOr); - case Instruction::Xor: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getXor); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getAnd(C1, C2)); + } + return ConstantVector::get(Res); + case Instruction::Or: + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getOr(C1, C2)); + } + return ConstantVector::get(Res); + case Instruction::Xor: + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getXor(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::LShr: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getLShr); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getLShr(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::AShr: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getAShr); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getAShr(C1, C2)); + } + return ConstantVector::get(Res); case Instruction::Shl: - return EvalVectorOp(CP1, CP2, VTy, ConstantExpr::getShl); + for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) { + C1 = CP1 ? CP1->getOperand(i) : Constant::getNullValue(EltTy); + C2 = CP2 ? CP2->getOperand(i) : Constant::getNullValue(EltTy); + Res.push_back(ConstantExpr::getShl(C1, C2)); + } + return ConstantVector::get(Res); } } } @@ -876,8 +985,8 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, case Instruction::Or: case Instruction::Xor: // No change of opcode required. - return ConstantFoldBinaryInstruction(Opcode, C2, C1); - + return ConstantFoldBinaryInstruction(Context, Opcode, C2, C1); + case Instruction::Shl: case Instruction::LShr: case Instruction::AShr: @@ -893,7 +1002,36 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, break; } } - + + // i1 can be simplified in many cases. + if (C1->getType() == Type::getInt1Ty(Context)) { + switch (Opcode) { + case Instruction::Add: + case Instruction::Sub: + return ConstantExpr::getXor(C1, C2); + case Instruction::Mul: + return ConstantExpr::getAnd(C1, C2); + case Instruction::Shl: + case Instruction::LShr: + case Instruction::AShr: + // We can assume that C2 == 0. If it were one the result would be + // undefined because the shift value is as large as the bitwidth. + return C1; + case Instruction::SDiv: + case Instruction::UDiv: + // We can assume that C2 == 1. If it were zero the result would be + // undefined through division by zero. + return C1; + case Instruction::URem: + case Instruction::SRem: + // We can assume that C2 == 1. If it were zero the result would be + // undefined through division by zero. + return ConstantInt::getFalse(Context); + default: + break; + } + } + // We don't know how to fold this. return 0; } @@ -922,7 +1060,8 @@ static bool isMaybeZeroSizedType(const Type *Ty) { /// first is less than the second, return -1, if the second is less than the /// first, return 1. If the constants are not integral, return -2. /// -static int IdxCompare(Constant *C1, Constant *C2, const Type *ElTy) { +static int IdxCompare(LLVMContext &Context, Constant *C1, Constant *C2, + const Type *ElTy) { if (C1 == C2) return 0; // Ok, we found a different index. If they are not ConstantInt, we can't do @@ -932,11 +1071,11 @@ static int IdxCompare(Constant *C1, Constant *C2, const Type *ElTy) { // Ok, we have two differing integer indices. Sign extend them to be the same // type. Long is always big enough, so we use it. - if (C1->getType() != Type::Int64Ty) - C1 = ConstantExpr::getSExt(C1, Type::Int64Ty); + if (C1->getType() != Type::getInt64Ty(Context)) + C1 = ConstantExpr::getSExt(C1, Type::getInt64Ty(Context)); - if (C2->getType() != Type::Int64Ty) - C2 = ConstantExpr::getSExt(C2, Type::Int64Ty); + if (C2->getType() != Type::getInt64Ty(Context)) + C2 = ConstantExpr::getSExt(C2, Type::getInt64Ty(Context)); if (C1 == C2) return 0; // They are equal @@ -965,13 +1104,13 @@ static int IdxCompare(Constant *C1, Constant *C2, const Type *ElTy) { /// To simplify this code we canonicalize the relation so that the first /// operand is always the most "complex" of the two. We consider ConstantFP /// to be the simplest, and ConstantExprs to be the most complex. -static FCmpInst::Predicate evaluateFCmpRelation(const Constant *V1, - const Constant *V2) { +static FCmpInst::Predicate evaluateFCmpRelation(LLVMContext &Context, + Constant *V1, Constant *V2) { assert(V1->getType() == V2->getType() && "Cannot compare values of different types!"); // No compile-time operations on this type yet. - if (V1->getType() == Type::PPC_FP128Ty) + if (V1->getType()->isPPC_FP128Ty()) return FCmpInst::BAD_FCMP_PREDICATE; // Handle degenerate case quickly @@ -981,33 +1120,31 @@ static FCmpInst::Predicate evaluateFCmpRelation(const Constant *V1, if (!isa<ConstantExpr>(V2)) { // We distilled thisUse the standard constant folder for a few cases ConstantInt *R = 0; - Constant *C1 = const_cast<Constant*>(V1); - Constant *C2 = const_cast<Constant*>(V2); R = dyn_cast<ConstantInt>( - ConstantExpr::getFCmp(FCmpInst::FCMP_OEQ, C1, C2)); + ConstantExpr::getFCmp(FCmpInst::FCMP_OEQ, V1, V2)); if (R && !R->isZero()) return FCmpInst::FCMP_OEQ; R = dyn_cast<ConstantInt>( - ConstantExpr::getFCmp(FCmpInst::FCMP_OLT, C1, C2)); + ConstantExpr::getFCmp(FCmpInst::FCMP_OLT, V1, V2)); if (R && !R->isZero()) return FCmpInst::FCMP_OLT; R = dyn_cast<ConstantInt>( - ConstantExpr::getFCmp(FCmpInst::FCMP_OGT, C1, C2)); + ConstantExpr::getFCmp(FCmpInst::FCMP_OGT, V1, V2)); if (R && !R->isZero()) return FCmpInst::FCMP_OGT; // Nothing more we can do return FCmpInst::BAD_FCMP_PREDICATE; } - + // If the first operand is simple and second is ConstantExpr, swap operands. - FCmpInst::Predicate SwappedRelation = evaluateFCmpRelation(V2, V1); + FCmpInst::Predicate SwappedRelation = evaluateFCmpRelation(Context, V2, V1); if (SwappedRelation != FCmpInst::BAD_FCMP_PREDICATE) return FCmpInst::getSwappedPredicate(SwappedRelation); } else { // Ok, the LHS is known to be a constantexpr. The RHS can be any of a // constantexpr or a simple constant. - const ConstantExpr *CE1 = cast<ConstantExpr>(V1); + ConstantExpr *CE1 = cast<ConstantExpr>(V1); switch (CE1->getOpcode()) { case Instruction::FPTrunc: case Instruction::FPExt: @@ -1036,8 +1173,9 @@ static FCmpInst::Predicate evaluateFCmpRelation(const Constant *V1, /// constants (like ConstantInt) to be the simplest, followed by /// GlobalValues, followed by ConstantExpr's (the most complex). /// -static ICmpInst::Predicate evaluateICmpRelation(const Constant *V1, - const Constant *V2, +static ICmpInst::Predicate evaluateICmpRelation(LLVMContext &Context, + Constant *V1, + Constant *V2, bool isSigned) { assert(V1->getType() == V2->getType() && "Cannot compare different types of values!"); @@ -1048,35 +1186,33 @@ static ICmpInst::Predicate evaluateICmpRelation(const Constant *V1, // We distilled this down to a simple case, use the standard constant // folder. ConstantInt *R = 0; - Constant *C1 = const_cast<Constant*>(V1); - Constant *C2 = const_cast<Constant*>(V2); ICmpInst::Predicate pred = ICmpInst::ICMP_EQ; - R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, C1, C2)); + R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, V1, V2)); if (R && !R->isZero()) return pred; pred = isSigned ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT; - R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, C1, C2)); + R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, V1, V2)); if (R && !R->isZero()) return pred; - pred = isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT; - R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, C1, C2)); + pred = isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT; + R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, V1, V2)); if (R && !R->isZero()) return pred; - + // If we couldn't figure it out, bail. return ICmpInst::BAD_ICMP_PREDICATE; } - + // If the first operand is simple, swap operands. ICmpInst::Predicate SwappedRelation = - evaluateICmpRelation(V2, V1, isSigned); + evaluateICmpRelation(Context, V2, V1, isSigned); if (SwappedRelation != ICmpInst::BAD_ICMP_PREDICATE) return ICmpInst::getSwappedPredicate(SwappedRelation); } else if (const GlobalValue *CPR1 = dyn_cast<GlobalValue>(V1)) { if (isa<ConstantExpr>(V2)) { // Swap as necessary. ICmpInst::Predicate SwappedRelation = - evaluateICmpRelation(V2, V1, isSigned); + evaluateICmpRelation(Context, V2, V1, isSigned); if (SwappedRelation != ICmpInst::BAD_ICMP_PREDICATE) return ICmpInst::getSwappedPredicate(SwappedRelation); else @@ -1099,8 +1235,8 @@ static ICmpInst::Predicate evaluateICmpRelation(const Constant *V1, } else { // Ok, the LHS is known to be a constantexpr. The RHS can be any of a // constantexpr, a CPR, or a simple constant. - const ConstantExpr *CE1 = cast<ConstantExpr>(V1); - const Constant *CE1Op0 = CE1->getOperand(0); + ConstantExpr *CE1 = cast<ConstantExpr>(V1); + Constant *CE1Op0 = CE1->getOperand(0); switch (CE1->getOpcode()) { case Instruction::Trunc: @@ -1119,28 +1255,12 @@ static ICmpInst::Predicate evaluateICmpRelation(const Constant *V1, // null pointer, do the comparison with the pre-casted value. if (V2->isNullValue() && (isa<PointerType>(CE1->getType()) || CE1->getType()->isInteger())) { - bool sgnd = isSigned; if (CE1->getOpcode() == Instruction::ZExt) isSigned = false; if (CE1->getOpcode() == Instruction::SExt) isSigned = true; - return evaluateICmpRelation(CE1Op0, + return evaluateICmpRelation(Context, CE1Op0, Constant::getNullValue(CE1Op0->getType()), - sgnd); + isSigned); } - - // If the dest type is a pointer type, and the RHS is a constantexpr cast - // from the same type as the src of the LHS, evaluate the inputs. This is - // important for things like "icmp eq (cast 4 to int*), (cast 5 to int*)", - // which happens a lot in compilers with tagged integers. - if (const ConstantExpr *CE2 = dyn_cast<ConstantExpr>(V2)) - if (CE2->isCast() && isa<PointerType>(CE1->getType()) && - CE1->getOperand(0)->getType() == CE2->getOperand(0)->getType() && - CE1->getOperand(0)->getType()->isInteger()) { - bool sgnd = isSigned; - if (CE1->getOpcode() == Instruction::ZExt) isSigned = false; - if (CE1->getOpcode() == Instruction::SExt) isSigned = true; - return evaluateICmpRelation(CE1->getOperand(0), CE2->getOperand(0), - sgnd); - } break; case Instruction::GetElementPtr: @@ -1157,7 +1277,7 @@ static ICmpInst::Predicate evaluateICmpRelation(const Constant *V1, else // If its not weak linkage, the GVal must have a non-zero address // so the result is greater-than - return isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT; + return isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT; } else if (isa<ConstantPointerNull>(CE1Op0)) { // If we are indexing from a null pointer, check to see if we have any // non-zero indices. @@ -1196,8 +1316,8 @@ static ICmpInst::Predicate evaluateICmpRelation(const Constant *V1, } } } else { - const ConstantExpr *CE2 = cast<ConstantExpr>(V2); - const Constant *CE2Op0 = CE2->getOperand(0); + ConstantExpr *CE2 = cast<ConstantExpr>(V2); + Constant *CE2Op0 = CE2->getOperand(0); // There are MANY other foldings that we could perform here. They will // probably be added on demand, as they seem needed. @@ -1214,12 +1334,20 @@ static ICmpInst::Predicate evaluateICmpRelation(const Constant *V1, // ordering of the resultant pointers. unsigned i = 1; + // The logic below assumes that the result of the comparison + // can be determined by finding the first index that differs. + // This doesn't work if there is over-indexing in any + // subsequent indices, so check for that case first. + if (!CE1->isGEPWithNoNotionalOverIndexing() || + !CE2->isGEPWithNoNotionalOverIndexing()) + return ICmpInst::BAD_ICMP_PREDICATE; // Might be equal. + // Compare all of the operands the GEP's have in common. gep_type_iterator GTI = gep_type_begin(CE1); for (;i != CE1->getNumOperands() && i != CE2->getNumOperands(); ++i, ++GTI) - switch (IdxCompare(CE1->getOperand(i), CE2->getOperand(i), - GTI.getIndexedType())) { + switch (IdxCompare(Context, CE1->getOperand(i), + CE2->getOperand(i), GTI.getIndexedType())) { case -1: return isSigned ? ICmpInst::ICMP_SLT:ICmpInst::ICMP_ULT; case 1: return isSigned ? ICmpInst::ICMP_SGT:ICmpInst::ICMP_UGT; case -2: return ICmpInst::BAD_ICMP_PREDICATE; @@ -1254,36 +1382,28 @@ static ICmpInst::Predicate evaluateICmpRelation(const Constant *V1, return ICmpInst::BAD_ICMP_PREDICATE; } -Constant *llvm::ConstantFoldCompareInstruction(unsigned short pred, - const Constant *C1, - const Constant *C2) { +Constant *llvm::ConstantFoldCompareInstruction(LLVMContext &Context, + unsigned short pred, + Constant *C1, Constant *C2) { + const Type *ResultTy; + if (const VectorType *VT = dyn_cast<VectorType>(C1->getType())) + ResultTy = VectorType::get(Type::getInt1Ty(Context), VT->getNumElements()); + else + ResultTy = Type::getInt1Ty(Context); + // Fold FCMP_FALSE/FCMP_TRUE unconditionally. - if (pred == FCmpInst::FCMP_FALSE) { - if (const VectorType *VT = dyn_cast<VectorType>(C1->getType())) - return Constant::getNullValue(VectorType::getInteger(VT)); - else - return ConstantInt::getFalse(); - } - - if (pred == FCmpInst::FCMP_TRUE) { - if (const VectorType *VT = dyn_cast<VectorType>(C1->getType())) - return Constant::getAllOnesValue(VectorType::getInteger(VT)); - else - return ConstantInt::getTrue(); - } - + if (pred == FCmpInst::FCMP_FALSE) + return Constant::getNullValue(ResultTy); + + if (pred == FCmpInst::FCMP_TRUE) + return Constant::getAllOnesValue(ResultTy); + // Handle some degenerate cases first - if (isa<UndefValue>(C1) || isa<UndefValue>(C2)) { - // vicmp/vfcmp -> [vector] undef - if (const VectorType *VTy = dyn_cast<VectorType>(C1->getType())) - return UndefValue::get(VectorType::getInteger(VTy)); - - // icmp/fcmp -> i1 undef - return UndefValue::get(Type::Int1Ty); - } + if (isa<UndefValue>(C1) || isa<UndefValue>(C2)) + return UndefValue::get(ResultTy); // No compile-time operations on this type yet. - if (C1->getType() == Type::PPC_FP128Ty) + if (C1->getType()->isPPC_FP128Ty()) return 0; // icmp eq/ne(null,GV) -> false/true @@ -1292,9 +1412,9 @@ Constant *llvm::ConstantFoldCompareInstruction(unsigned short pred, // Don't try to evaluate aliases. External weak GV can be null. if (!isa<GlobalAlias>(GV) && !GV->hasExternalWeakLinkage()) { if (pred == ICmpInst::ICMP_EQ) - return ConstantInt::getFalse(); + return ConstantInt::getFalse(Context); else if (pred == ICmpInst::ICMP_NE) - return ConstantInt::getTrue(); + return ConstantInt::getTrue(Context); } // icmp eq/ne(GV,null) -> false/true } else if (C2->isNullValue()) { @@ -1302,114 +1422,115 @@ Constant *llvm::ConstantFoldCompareInstruction(unsigned short pred, // Don't try to evaluate aliases. External weak GV can be null. if (!isa<GlobalAlias>(GV) && !GV->hasExternalWeakLinkage()) { if (pred == ICmpInst::ICMP_EQ) - return ConstantInt::getFalse(); + return ConstantInt::getFalse(Context); else if (pred == ICmpInst::ICMP_NE) - return ConstantInt::getTrue(); + return ConstantInt::getTrue(Context); } } + // If the comparison is a comparison between two i1's, simplify it. + if (C1->getType() == Type::getInt1Ty(Context)) { + switch(pred) { + case ICmpInst::ICMP_EQ: + if (isa<ConstantInt>(C2)) + return ConstantExpr::getXor(C1, ConstantExpr::getNot(C2)); + return ConstantExpr::getXor(ConstantExpr::getNot(C1), C2); + case ICmpInst::ICMP_NE: + return ConstantExpr::getXor(C1, C2); + default: + break; + } + } + if (isa<ConstantInt>(C1) && isa<ConstantInt>(C2)) { APInt V1 = cast<ConstantInt>(C1)->getValue(); APInt V2 = cast<ConstantInt>(C2)->getValue(); switch (pred) { - default: assert(0 && "Invalid ICmp Predicate"); return 0; - case ICmpInst::ICMP_EQ: return ConstantInt::get(Type::Int1Ty, V1 == V2); - case ICmpInst::ICMP_NE: return ConstantInt::get(Type::Int1Ty, V1 != V2); - case ICmpInst::ICMP_SLT:return ConstantInt::get(Type::Int1Ty, V1.slt(V2)); - case ICmpInst::ICMP_SGT:return ConstantInt::get(Type::Int1Ty, V1.sgt(V2)); - case ICmpInst::ICMP_SLE:return ConstantInt::get(Type::Int1Ty, V1.sle(V2)); - case ICmpInst::ICMP_SGE:return ConstantInt::get(Type::Int1Ty, V1.sge(V2)); - case ICmpInst::ICMP_ULT:return ConstantInt::get(Type::Int1Ty, V1.ult(V2)); - case ICmpInst::ICMP_UGT:return ConstantInt::get(Type::Int1Ty, V1.ugt(V2)); - case ICmpInst::ICMP_ULE:return ConstantInt::get(Type::Int1Ty, V1.ule(V2)); - case ICmpInst::ICMP_UGE:return ConstantInt::get(Type::Int1Ty, V1.uge(V2)); + default: llvm_unreachable("Invalid ICmp Predicate"); return 0; + case ICmpInst::ICMP_EQ: + return ConstantInt::get(Type::getInt1Ty(Context), V1 == V2); + case ICmpInst::ICMP_NE: + return ConstantInt::get(Type::getInt1Ty(Context), V1 != V2); + case ICmpInst::ICMP_SLT: + return ConstantInt::get(Type::getInt1Ty(Context), V1.slt(V2)); + case ICmpInst::ICMP_SGT: + return ConstantInt::get(Type::getInt1Ty(Context), V1.sgt(V2)); + case ICmpInst::ICMP_SLE: + return ConstantInt::get(Type::getInt1Ty(Context), V1.sle(V2)); + case ICmpInst::ICMP_SGE: + return ConstantInt::get(Type::getInt1Ty(Context), V1.sge(V2)); + case ICmpInst::ICMP_ULT: + return ConstantInt::get(Type::getInt1Ty(Context), V1.ult(V2)); + case ICmpInst::ICMP_UGT: + return ConstantInt::get(Type::getInt1Ty(Context), V1.ugt(V2)); + case ICmpInst::ICMP_ULE: + return ConstantInt::get(Type::getInt1Ty(Context), V1.ule(V2)); + case ICmpInst::ICMP_UGE: + return ConstantInt::get(Type::getInt1Ty(Context), V1.uge(V2)); } } else if (isa<ConstantFP>(C1) && isa<ConstantFP>(C2)) { APFloat C1V = cast<ConstantFP>(C1)->getValueAPF(); APFloat C2V = cast<ConstantFP>(C2)->getValueAPF(); APFloat::cmpResult R = C1V.compare(C2V); switch (pred) { - default: assert(0 && "Invalid FCmp Predicate"); return 0; - case FCmpInst::FCMP_FALSE: return ConstantInt::getFalse(); - case FCmpInst::FCMP_TRUE: return ConstantInt::getTrue(); + default: llvm_unreachable("Invalid FCmp Predicate"); return 0; + case FCmpInst::FCMP_FALSE: return ConstantInt::getFalse(Context); + case FCmpInst::FCMP_TRUE: return ConstantInt::getTrue(Context); case FCmpInst::FCMP_UNO: - return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpUnordered); + return ConstantInt::get(Type::getInt1Ty(Context), R==APFloat::cmpUnordered); case FCmpInst::FCMP_ORD: - return ConstantInt::get(Type::Int1Ty, R!=APFloat::cmpUnordered); + return ConstantInt::get(Type::getInt1Ty(Context), R!=APFloat::cmpUnordered); case FCmpInst::FCMP_UEQ: - return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpUnordered || + return ConstantInt::get(Type::getInt1Ty(Context), R==APFloat::cmpUnordered || R==APFloat::cmpEqual); case FCmpInst::FCMP_OEQ: - return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpEqual); + return ConstantInt::get(Type::getInt1Ty(Context), R==APFloat::cmpEqual); case FCmpInst::FCMP_UNE: - return ConstantInt::get(Type::Int1Ty, R!=APFloat::cmpEqual); + return ConstantInt::get(Type::getInt1Ty(Context), R!=APFloat::cmpEqual); case FCmpInst::FCMP_ONE: - return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpLessThan || + return ConstantInt::get(Type::getInt1Ty(Context), R==APFloat::cmpLessThan || R==APFloat::cmpGreaterThan); case FCmpInst::FCMP_ULT: - return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpUnordered || + return ConstantInt::get(Type::getInt1Ty(Context), R==APFloat::cmpUnordered || R==APFloat::cmpLessThan); case FCmpInst::FCMP_OLT: - return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpLessThan); + return ConstantInt::get(Type::getInt1Ty(Context), R==APFloat::cmpLessThan); case FCmpInst::FCMP_UGT: - return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpUnordered || + return ConstantInt::get(Type::getInt1Ty(Context), R==APFloat::cmpUnordered || R==APFloat::cmpGreaterThan); case FCmpInst::FCMP_OGT: - return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpGreaterThan); + return ConstantInt::get(Type::getInt1Ty(Context), R==APFloat::cmpGreaterThan); case FCmpInst::FCMP_ULE: - return ConstantInt::get(Type::Int1Ty, R!=APFloat::cmpGreaterThan); + return ConstantInt::get(Type::getInt1Ty(Context), R!=APFloat::cmpGreaterThan); case FCmpInst::FCMP_OLE: - return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpLessThan || + return ConstantInt::get(Type::getInt1Ty(Context), R==APFloat::cmpLessThan || R==APFloat::cmpEqual); case FCmpInst::FCMP_UGE: - return ConstantInt::get(Type::Int1Ty, R!=APFloat::cmpLessThan); + return ConstantInt::get(Type::getInt1Ty(Context), R!=APFloat::cmpLessThan); case FCmpInst::FCMP_OGE: - return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpGreaterThan || + return ConstantInt::get(Type::getInt1Ty(Context), R==APFloat::cmpGreaterThan || R==APFloat::cmpEqual); } } else if (isa<VectorType>(C1->getType())) { SmallVector<Constant*, 16> C1Elts, C2Elts; - C1->getVectorElements(C1Elts); - C2->getVectorElements(C2Elts); - + C1->getVectorElements(Context, C1Elts); + C2->getVectorElements(Context, C2Elts); + // If we can constant fold the comparison of each element, constant fold // the whole vector comparison. SmallVector<Constant*, 4> ResElts; - const Type *InEltTy = C1Elts[0]->getType(); - bool isFP = InEltTy->isFloatingPoint(); - const Type *ResEltTy = InEltTy; - if (isFP) - ResEltTy = IntegerType::get(InEltTy->getPrimitiveSizeInBits()); - for (unsigned i = 0, e = C1Elts.size(); i != e; ++i) { // Compare the elements, producing an i1 result or constant expr. - Constant *C; - if (isFP) - C = ConstantExpr::getFCmp(pred, C1Elts[i], C2Elts[i]); - else - C = ConstantExpr::getICmp(pred, C1Elts[i], C2Elts[i]); - - // If it is a bool or undef result, convert to the dest type. - if (ConstantInt *CI = dyn_cast<ConstantInt>(C)) { - if (CI->isZero()) - ResElts.push_back(Constant::getNullValue(ResEltTy)); - else - ResElts.push_back(Constant::getAllOnesValue(ResEltTy)); - } else if (isa<UndefValue>(C)) { - ResElts.push_back(UndefValue::get(ResEltTy)); - } else { - break; - } + ResElts.push_back( + ConstantExpr::getCompare(pred, C1Elts[i], C2Elts[i])); } - - if (ResElts.size() == C1Elts.size()) - return ConstantVector::get(&ResElts[0], ResElts.size()); + return ConstantVector::get(&ResElts[0], ResElts.size()); } if (C1->getType()->isFloatingPoint()) { int Result = -1; // -1 = unknown, 0 = known false, 1 = known true. - switch (evaluateFCmpRelation(C1, C2)) { - default: assert(0 && "Unknown relation!"); + switch (evaluateFCmpRelation(Context, C1, C2)) { + default: llvm_unreachable("Unknown relation!"); case FCmpInst::FCMP_UNO: case FCmpInst::FCMP_ORD: case FCmpInst::FCMP_UEQ: @@ -1459,110 +1580,115 @@ Constant *llvm::ConstantFoldCompareInstruction(unsigned short pred, Result = 1; break; } - + // If we evaluated the result, return it now. - if (Result != -1) { - if (const VectorType *VT = dyn_cast<VectorType>(C1->getType())) { - if (Result == 0) - return Constant::getNullValue(VectorType::getInteger(VT)); - else - return Constant::getAllOnesValue(VectorType::getInteger(VT)); - } - return ConstantInt::get(Type::Int1Ty, Result); - } - + if (Result != -1) + return ConstantInt::get(Type::getInt1Ty(Context), Result); + } else { // Evaluate the relation between the two constants, per the predicate. int Result = -1; // -1 = unknown, 0 = known false, 1 = known true. - switch (evaluateICmpRelation(C1, C2, CmpInst::isSigned(pred))) { - default: assert(0 && "Unknown relational!"); + switch (evaluateICmpRelation(Context, C1, C2, CmpInst::isSigned(pred))) { + default: llvm_unreachable("Unknown relational!"); case ICmpInst::BAD_ICMP_PREDICATE: break; // Couldn't determine anything about these constants. case ICmpInst::ICMP_EQ: // We know the constants are equal! // If we know the constants are equal, we can decide the result of this // computation precisely. - Result = (pred == ICmpInst::ICMP_EQ || - pred == ICmpInst::ICMP_ULE || - pred == ICmpInst::ICMP_SLE || - pred == ICmpInst::ICMP_UGE || - pred == ICmpInst::ICMP_SGE); + Result = ICmpInst::isTrueWhenEqual((ICmpInst::Predicate)pred); break; case ICmpInst::ICMP_ULT: - // If we know that C1 < C2, we can decide the result of this computation - // precisely. - Result = (pred == ICmpInst::ICMP_ULT || - pred == ICmpInst::ICMP_NE || - pred == ICmpInst::ICMP_ULE); + switch (pred) { + case ICmpInst::ICMP_ULT: case ICmpInst::ICMP_NE: case ICmpInst::ICMP_ULE: + Result = 1; break; + case ICmpInst::ICMP_UGT: case ICmpInst::ICMP_EQ: case ICmpInst::ICMP_UGE: + Result = 0; break; + } break; case ICmpInst::ICMP_SLT: - // If we know that C1 < C2, we can decide the result of this computation - // precisely. - Result = (pred == ICmpInst::ICMP_SLT || - pred == ICmpInst::ICMP_NE || - pred == ICmpInst::ICMP_SLE); + switch (pred) { + case ICmpInst::ICMP_SLT: case ICmpInst::ICMP_NE: case ICmpInst::ICMP_SLE: + Result = 1; break; + case ICmpInst::ICMP_SGT: case ICmpInst::ICMP_EQ: case ICmpInst::ICMP_SGE: + Result = 0; break; + } break; case ICmpInst::ICMP_UGT: - // If we know that C1 > C2, we can decide the result of this computation - // precisely. - Result = (pred == ICmpInst::ICMP_UGT || - pred == ICmpInst::ICMP_NE || - pred == ICmpInst::ICMP_UGE); + switch (pred) { + case ICmpInst::ICMP_UGT: case ICmpInst::ICMP_NE: case ICmpInst::ICMP_UGE: + Result = 1; break; + case ICmpInst::ICMP_ULT: case ICmpInst::ICMP_EQ: case ICmpInst::ICMP_ULE: + Result = 0; break; + } break; case ICmpInst::ICMP_SGT: - // If we know that C1 > C2, we can decide the result of this computation - // precisely. - Result = (pred == ICmpInst::ICMP_SGT || - pred == ICmpInst::ICMP_NE || - pred == ICmpInst::ICMP_SGE); + switch (pred) { + case ICmpInst::ICMP_SGT: case ICmpInst::ICMP_NE: case ICmpInst::ICMP_SGE: + Result = 1; break; + case ICmpInst::ICMP_SLT: case ICmpInst::ICMP_EQ: case ICmpInst::ICMP_SLE: + Result = 0; break; + } break; case ICmpInst::ICMP_ULE: - // If we know that C1 <= C2, we can only partially decide this relation. if (pred == ICmpInst::ICMP_UGT) Result = 0; - if (pred == ICmpInst::ICMP_ULT) Result = 1; + if (pred == ICmpInst::ICMP_ULT || pred == ICmpInst::ICMP_ULE) Result = 1; break; case ICmpInst::ICMP_SLE: - // If we know that C1 <= C2, we can only partially decide this relation. if (pred == ICmpInst::ICMP_SGT) Result = 0; - if (pred == ICmpInst::ICMP_SLT) Result = 1; + if (pred == ICmpInst::ICMP_SLT || pred == ICmpInst::ICMP_SLE) Result = 1; break; - case ICmpInst::ICMP_UGE: - // If we know that C1 >= C2, we can only partially decide this relation. if (pred == ICmpInst::ICMP_ULT) Result = 0; - if (pred == ICmpInst::ICMP_UGT) Result = 1; + if (pred == ICmpInst::ICMP_UGT || pred == ICmpInst::ICMP_UGE) Result = 1; break; case ICmpInst::ICMP_SGE: - // If we know that C1 >= C2, we can only partially decide this relation. if (pred == ICmpInst::ICMP_SLT) Result = 0; - if (pred == ICmpInst::ICMP_SGT) Result = 1; + if (pred == ICmpInst::ICMP_SGT || pred == ICmpInst::ICMP_SGE) Result = 1; break; - case ICmpInst::ICMP_NE: - // If we know that C1 != C2, we can only partially decide this relation. if (pred == ICmpInst::ICMP_EQ) Result = 0; if (pred == ICmpInst::ICMP_NE) Result = 1; break; } - + // If we evaluated the result, return it now. - if (Result != -1) { - if (const VectorType *VT = dyn_cast<VectorType>(C1->getType())) { - if (Result == 0) - return Constant::getNullValue(VT); - else - return Constant::getAllOnesValue(VT); + if (Result != -1) + return ConstantInt::get(Type::getInt1Ty(Context), Result); + + // If the right hand side is a bitcast, try using its inverse to simplify + // it by moving it to the left hand side. + if (ConstantExpr *CE2 = dyn_cast<ConstantExpr>(C2)) { + if (CE2->getOpcode() == Instruction::BitCast) { + Constant *CE2Op0 = CE2->getOperand(0); + Constant *Inverse = ConstantExpr::getBitCast(C1, CE2Op0->getType()); + return ConstantExpr::getICmp(pred, Inverse, CE2Op0); } - return ConstantInt::get(Type::Int1Ty, Result); } - + + // If the left hand side is an extension, try eliminating it. + if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) { + if (CE1->getOpcode() == Instruction::SExt || + CE1->getOpcode() == Instruction::ZExt) { + Constant *CE1Op0 = CE1->getOperand(0); + Constant *CE1Inverse = ConstantExpr::getTrunc(CE1, CE1Op0->getType()); + if (CE1Inverse == CE1Op0) { + // Check whether we can safely truncate the right hand side. + Constant *C2Inverse = ConstantExpr::getTrunc(C2, CE1Op0->getType()); + if (ConstantExpr::getZExt(C2Inverse, C2->getType()) == C2) { + return ConstantExpr::getICmp(pred, CE1Inverse, C2Inverse); + } + } + } + } + if (!isa<ConstantExpr>(C1) && isa<ConstantExpr>(C2)) { - // If C2 is a constant expr and C1 isn't, flop them around and fold the + // If C2 is a constant expr and C1 isn't, flip them around and fold the // other way if possible. switch (pred) { case ICmpInst::ICMP_EQ: case ICmpInst::ICMP_NE: // No change of predicate required. - return ConstantFoldCompareInstruction(pred, C2, C1); + return ConstantFoldCompareInstruction(Context, pred, C2, C1); case ICmpInst::ICMP_ULT: case ICmpInst::ICMP_SLT: @@ -1574,7 +1700,7 @@ Constant *llvm::ConstantFoldCompareInstruction(unsigned short pred, case ICmpInst::ICMP_SGE: // Change the predicate as necessary to swap the operands. pred = ICmpInst::getSwappedPredicate((ICmpInst::Predicate)pred); - return ConstantFoldCompareInstruction(pred, C2, C1); + return ConstantFoldCompareInstruction(Context, pred, C2, C1); default: // These predicates cannot be flopped around. break; @@ -1584,12 +1710,33 @@ Constant *llvm::ConstantFoldCompareInstruction(unsigned short pred, return 0; } -Constant *llvm::ConstantFoldGetElementPtr(const Constant *C, +/// isInBoundsIndices - Test whether the given sequence of *normalized* indices +/// is "inbounds". +static bool isInBoundsIndices(Constant *const *Idxs, size_t NumIdx) { + // No indices means nothing that could be out of bounds. + if (NumIdx == 0) return true; + + // If the first index is zero, it's in bounds. + if (Idxs[0]->isNullValue()) return true; + + // If the first index is one and all the rest are zero, it's in bounds, + // by the one-past-the-end rule. + if (!cast<ConstantInt>(Idxs[0])->isOne()) + return false; + for (unsigned i = 1, e = NumIdx; i != e; ++i) + if (!Idxs[i]->isNullValue()) + return false; + return true; +} + +Constant *llvm::ConstantFoldGetElementPtr(LLVMContext &Context, + Constant *C, + bool inBounds, Constant* const *Idxs, unsigned NumIdx) { if (NumIdx == 0 || (NumIdx == 1 && Idxs[0]->isNullValue())) - return const_cast<Constant*>(C); + return C; if (isa<UndefValue>(C)) { const PointerType *Ptr = cast<PointerType>(C->getType()); @@ -1614,12 +1761,12 @@ Constant *llvm::ConstantFoldGetElementPtr(const Constant *C, (Value**)Idxs, (Value**)Idxs+NumIdx); assert(Ty != 0 && "Invalid indices for GEP!"); - return - ConstantPointerNull::get(PointerType::get(Ty,Ptr->getAddressSpace())); + return ConstantPointerNull::get( + PointerType::get(Ty,Ptr->getAddressSpace())); } } - if (ConstantExpr *CE = dyn_cast<ConstantExpr>(const_cast<Constant*>(C))) { + if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) { // Combine Indices - If the source pointer to this getelementptr instruction // is a getelementptr instruction, combine the indices of the two // getelementptr instructions into a single instruction. @@ -1643,9 +1790,10 @@ Constant *llvm::ConstantFoldGetElementPtr(const Constant *C, if (!Idx0->isNullValue()) { const Type *IdxTy = Combined->getType(); if (IdxTy != Idx0->getType()) { - Constant *C1 = ConstantExpr::getSExtOrBitCast(Idx0, Type::Int64Ty); + Constant *C1 = + ConstantExpr::getSExtOrBitCast(Idx0, Type::getInt64Ty(Context)); Constant *C2 = ConstantExpr::getSExtOrBitCast(Combined, - Type::Int64Ty); + Type::getInt64Ty(Context)); Combined = ConstantExpr::get(Instruction::Add, C1, C2); } else { Combined = @@ -1655,8 +1803,13 @@ Constant *llvm::ConstantFoldGetElementPtr(const Constant *C, NewIndices.push_back(Combined); NewIndices.insert(NewIndices.end(), Idxs+1, Idxs+NumIdx); - return ConstantExpr::getGetElementPtr(CE->getOperand(0), &NewIndices[0], - NewIndices.size()); + return (inBounds && cast<GEPOperator>(CE)->isInBounds()) ? + ConstantExpr::getInBoundsGetElementPtr(CE->getOperand(0), + &NewIndices[0], + NewIndices.size()) : + ConstantExpr::getGetElementPtr(CE->getOperand(0), + &NewIndices[0], + NewIndices.size()); } } @@ -1672,19 +1825,23 @@ Constant *llvm::ConstantFoldGetElementPtr(const Constant *C, if (const ArrayType *CAT = dyn_cast<ArrayType>(cast<PointerType>(C->getType())->getElementType())) if (CAT->getElementType() == SAT->getElementType()) - return ConstantExpr::getGetElementPtr( + return inBounds ? + ConstantExpr::getInBoundsGetElementPtr( + (Constant*)CE->getOperand(0), Idxs, NumIdx) : + ConstantExpr::getGetElementPtr( (Constant*)CE->getOperand(0), Idxs, NumIdx); } - + // Fold: getelementptr (i8* inttoptr (i64 1 to i8*), i32 -1) // Into: inttoptr (i64 0 to i8*) // This happens with pointers to member functions in C++. if (CE->getOpcode() == Instruction::IntToPtr && NumIdx == 1 && isa<ConstantInt>(CE->getOperand(0)) && isa<ConstantInt>(Idxs[0]) && - cast<PointerType>(CE->getType())->getElementType() == Type::Int8Ty) { + cast<PointerType>(CE->getType())->getElementType() == + Type::getInt8Ty(Context)) { Constant *Base = CE->getOperand(0); Constant *Offset = Idxs[0]; - + // Convert the smaller integer to the larger type. if (Offset->getType()->getPrimitiveSizeInBits() < Base->getType()->getPrimitiveSizeInBits()) @@ -1692,11 +1849,74 @@ Constant *llvm::ConstantFoldGetElementPtr(const Constant *C, else if (Base->getType()->getPrimitiveSizeInBits() < Offset->getType()->getPrimitiveSizeInBits()) Base = ConstantExpr::getZExt(Base, Offset->getType()); - + Base = ConstantExpr::getAdd(Base, Offset); return ConstantExpr::getIntToPtr(Base, CE->getType()); } } + + // Check to see if any array indices are not within the corresponding + // notional array bounds. If so, try to determine if they can be factored + // out into preceding dimensions. + bool Unknown = false; + SmallVector<Constant *, 8> NewIdxs; + const Type *Ty = C->getType(); + const Type *Prev = 0; + for (unsigned i = 0; i != NumIdx; + Prev = Ty, Ty = cast<CompositeType>(Ty)->getTypeAtIndex(Idxs[i]), ++i) { + if (ConstantInt *CI = dyn_cast<ConstantInt>(Idxs[i])) { + if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) + if (ATy->getNumElements() <= INT64_MAX && + ATy->getNumElements() != 0 && + CI->getSExtValue() >= (int64_t)ATy->getNumElements()) { + if (isa<SequentialType>(Prev)) { + // It's out of range, but we can factor it into the prior + // dimension. + NewIdxs.resize(NumIdx); + ConstantInt *Factor = ConstantInt::get(CI->getType(), + ATy->getNumElements()); + NewIdxs[i] = ConstantExpr::getSRem(CI, Factor); + + Constant *PrevIdx = Idxs[i-1]; + Constant *Div = ConstantExpr::getSDiv(CI, Factor); + + // Before adding, extend both operands to i64 to avoid + // overflow trouble. + if (PrevIdx->getType() != Type::getInt64Ty(Context)) + PrevIdx = ConstantExpr::getSExt(PrevIdx, + Type::getInt64Ty(Context)); + if (Div->getType() != Type::getInt64Ty(Context)) + Div = ConstantExpr::getSExt(Div, + Type::getInt64Ty(Context)); + + NewIdxs[i-1] = ConstantExpr::getAdd(PrevIdx, Div); + } else { + // It's out of range, but the prior dimension is a struct + // so we can't do anything about it. + Unknown = true; + } + } + } else { + // We don't know if it's in range or not. + Unknown = true; + } + } + + // If we did any factoring, start over with the adjusted indices. + if (!NewIdxs.empty()) { + for (unsigned i = 0; i != NumIdx; ++i) + if (!NewIdxs[i]) NewIdxs[i] = Idxs[i]; + return inBounds ? + ConstantExpr::getInBoundsGetElementPtr(C, NewIdxs.data(), + NewIdxs.size()) : + ConstantExpr::getGetElementPtr(C, NewIdxs.data(), NewIdxs.size()); + } + + // If all indices are known integers and normalized, we can do a simple + // check for the "inbounds" property. + if (!Unknown && !inBounds && + isa<GlobalVariable>(C) && isInBoundsIndices(Idxs, NumIdx)) + return ConstantExpr::getInBoundsGetElementPtr(C, Idxs, NumIdx); + return 0; } - |
