-//===- ConstantFolding.cpp - LLVM constant folder -------------------------===//
+//===- ConstantFold.cpp - LLVM constant folder ----------------------------===//
//
// The LLVM Compiler Infrastructure
//
//===----------------------------------------------------------------------===//
//
// This file implements folding of constants for LLVM. This implements the
-// (internal) ConstantFolding.h interface, which is used by the
+// (internal) ConstantFold.h interface, which is used by the
// ConstantExpr::get* methods to automatically fold constants when possible.
//
// The current constant folding implementation is implemented in two pieces: the
//
//===----------------------------------------------------------------------===//
-#include "ConstantFolding.h"
+#include "ConstantFold.h"
#include "llvm/Constants.h"
#include "llvm/Instructions.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
+#include "llvm/GlobalAlias.h"
+#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/ManagedStatic.h"
// ConstantFold*Instruction Implementations
//===----------------------------------------------------------------------===//
-/// CastConstantPacked - Convert the specified ConstantPacked node to the
-/// specified packed type. At this point, we know that the elements of the
-/// input packed constant are all simple integer or FP values.
-static Constant *CastConstantPacked(ConstantPacked *CP,
- const PackedType *DstTy) {
- unsigned SrcNumElts = CP->getType()->getNumElements();
+/// CastConstantVector - 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 *CastConstantVector(ConstantVector *CV,
+ const VectorType *DstTy) {
+ unsigned SrcNumElts = CV->getType()->getNumElements();
unsigned DstNumElts = DstTy->getNumElements();
- const Type *SrcEltTy = CP->getType()->getElementType();
+ const Type *SrcEltTy = CV->getType()->getElementType();
const Type *DstEltTy = DstTy->getElementType();
// If both vectors have the same number of elements (thus, the elements
(SrcEltTy->isFloatingPoint() && DstEltTy->isFloatingPoint())) {
for (unsigned i = 0; i != SrcNumElts; ++i)
Result.push_back(
- ConstantExpr::getBitCast(CP->getOperand(i), DstEltTy));
- return ConstantPacked::get(Result);
+ ConstantExpr::getBitCast(CV->getOperand(i), DstEltTy));
+ return ConstantVector::get(Result);
}
// If this is an int-to-fp cast ..
assert(DstEltTy->isFloatingPoint());
if (DstEltTy->getTypeID() == Type::DoubleTyID) {
for (unsigned i = 0; i != SrcNumElts; ++i) {
- double V =
- BitsToDouble(cast<ConstantInt>(CP->getOperand(i))->getZExtValue());
- Result.push_back(ConstantFP::get(Type::DoubleTy, V));
+ ConstantInt *CI = cast<ConstantInt>(CV->getOperand(i));
+ double V = CI->getValue().bitsToDouble();
+ Result.push_back(ConstantFP::get(Type::DoubleTy, APFloat(V)));
}
- return ConstantPacked::get(Result);
+ return ConstantVector::get(Result);
}
assert(DstEltTy == Type::FloatTy && "Unknown fp type!");
for (unsigned i = 0; i != SrcNumElts; ++i) {
- float V =
- BitsToFloat(cast<ConstantInt>(CP->getOperand(i))->getZExtValue());
- Result.push_back(ConstantFP::get(Type::FloatTy, V));
+ ConstantInt *CI = cast<ConstantInt>(CV->getOperand(i));
+ float V = CI->getValue().bitsToFloat();
+ Result.push_back(ConstantFP::get(Type::FloatTy, APFloat(V)));
}
- return ConstantPacked::get(Result);
+ return ConstantVector::get(Result);
}
// Otherwise, this is an fp-to-int cast.
if (SrcEltTy->getTypeID() == Type::DoubleTyID) {
for (unsigned i = 0; i != SrcNumElts; ++i) {
- uint64_t V =
- DoubleToBits(cast<ConstantFP>(CP->getOperand(i))->getValue());
+ uint64_t V = cast<ConstantFP>(CV->getOperand(i))->
+ getValueAPF().convertToAPInt().getZExtValue();
Constant *C = ConstantInt::get(Type::Int64Ty, V);
Result.push_back(ConstantExpr::getBitCast(C, DstEltTy ));
}
- return ConstantPacked::get(Result);
+ return ConstantVector::get(Result);
}
assert(SrcEltTy->getTypeID() == Type::FloatTyID);
for (unsigned i = 0; i != SrcNumElts; ++i) {
- uint32_t V = FloatToBits(cast<ConstantFP>(CP->getOperand(i))->getValue());
+ uint32_t V = (uint32_t)cast<ConstantFP>(CV->getOperand(i))->
+ getValueAPF().convertToAPInt().getZExtValue();
Constant *C = ConstantInt::get(Type::Int32Ty, V);
Result.push_back(ConstantExpr::getBitCast(C, DstEltTy));
}
- return ConstantPacked::get(Result);
+ return ConstantVector::get(Result);
}
// Otherwise, this is a cast that changes element count and size. Handle
/// This function determines which opcode to use to fold two constant cast
/// expressions together. It uses CastInst::isEliminableCastPair to determine
/// the opcode. Consequently its just a wrapper around that function.
-/// @Determine if it is valid to fold a cast of a cast
+/// @brief Determine if it is valid to fold a cast of a cast
static unsigned
foldConstantCastPair(
unsigned opc, ///< opcode of the second cast constant expression
const Type *DestTy) {
const Type *SrcTy = V->getType();
- if (isa<UndefValue>(V))
+ if (isa<UndefValue>(V)) {
+ // zext(undef) = 0, because the top bits will be zero.
+ // sext(undef) = 0, because the top bits will all be the same.
+ if (opc == Instruction::ZExt || opc == Instruction::SExt)
+ return Constant::getNullValue(DestTy);
return UndefValue::get(DestTy);
+ }
// If the cast operand is a constant expression, there's a few things we can
// do to try to simplify it.
switch (opc) {
case Instruction::FPTrunc:
case Instruction::FPExt:
- if (const ConstantFP *FPC = dyn_cast<ConstantFP>(V))
- return ConstantFP::get(DestTy, FPC->getValue());
+ if (const ConstantFP *FPC = dyn_cast<ConstantFP>(V)) {
+ 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 :
+ APFloat::Bogus,
+ APFloat::rmNearestTiesToEven);
+ return ConstantFP::get(DestTy, Val);
+ }
return 0; // Can't fold.
case Instruction::FPToUI:
- if (const ConstantFP *FPC = dyn_cast<ConstantFP>(V))
- return ConstantInt::get(DestTy,(uint64_t) FPC->getValue());
- return 0; // Can't fold.
case Instruction::FPToSI:
- if (const ConstantFP *FPC = dyn_cast<ConstantFP>(V))
- return ConstantInt::get(DestTy,(int64_t) FPC->getValue());
+ if (const ConstantFP *FPC = dyn_cast<ConstantFP>(V)) {
+ APFloat V = FPC->getValueAPF();
+ uint64_t x[2];
+ uint32_t DestBitWidth = cast<IntegerType>(DestTy)->getBitWidth();
+ (void) V.convertToInteger(x, DestBitWidth, opc==Instruction::FPToSI,
+ APFloat::rmTowardZero);
+ APInt Val(DestBitWidth, 2, x);
+ return ConstantInt::get(Val);
+ }
return 0; // Can't fold.
case Instruction::IntToPtr: //always treated as unsigned
if (V->isNullValue()) // Is it an integral null value?
return ConstantInt::get(DestTy, 0);
return 0; // Other pointer types cannot be casted
case Instruction::UIToFP:
- if (const ConstantInt *CI = dyn_cast<ConstantInt>(V))
- return ConstantFP::get(DestTy, double(CI->getZExtValue()));
+ if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
+ double d = CI->getValue().roundToDouble();
+ if (DestTy==Type::FloatTy)
+ return ConstantFP::get(DestTy, APFloat((float)d));
+ else if (DestTy==Type::DoubleTy)
+ return ConstantFP::get(DestTy, APFloat(d));
+ else
+ return 0; // FIXME do this for long double
+ }
return 0;
case Instruction::SIToFP:
- if (const ConstantInt *CI = dyn_cast<ConstantInt>(V))
- return ConstantFP::get(DestTy, double(CI->getSExtValue()));
+ if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
+ double d = CI->getValue().signedRoundToDouble();
+ if (DestTy==Type::FloatTy)
+ return ConstantFP::get(DestTy, APFloat((float)d));
+ else if (DestTy==Type::DoubleTy)
+ return ConstantFP::get(DestTy, APFloat(d));
+ else
+ return 0; // FIXME do this for long double
+ }
return 0;
case Instruction::ZExt:
- if (const ConstantInt *CI = dyn_cast<ConstantInt>(V))
- return ConstantInt::get(DestTy, CI->getZExtValue());
+ if (const 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 0;
case Instruction::SExt:
- if (const ConstantInt *CI = dyn_cast<ConstantInt>(V))
- return ConstantInt::get(DestTy, CI->getSExtValue());
+ if (const 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 0;
case Instruction::Trunc:
- if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) // Can't trunc a bool
- return ConstantInt::get(DestTy, CI->getZExtValue());
+ if (const 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 0;
case Instruction::BitCast:
if (SrcTy == DestTy)
// 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)) {
- std::vector<Value*> IdxList;
+ SmallVector<Value*, 8> IdxList;
IdxList.push_back(Constant::getNullValue(Type::Int32Ty));
const Type *ElTy = PTy->getElementType();
while (ElTy != DPTy->getElementType()) {
if (ElTy == DPTy->getElementType())
return ConstantExpr::getGetElementPtr(
- const_cast<Constant*>(V),IdxList);
+ const_cast<Constant*>(V), &IdxList[0], IdxList.size());
}
- // Handle casts from one packed constant to another. We know that the src
+ // 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 PackedType *DestPTy = dyn_cast<PackedType>(DestTy)) {
- if (const PackedType *SrcTy = dyn_cast<PackedType>(V->getType())) {
+ if (const VectorType *DestPTy = dyn_cast<VectorType>(DestTy)) {
+ if (const VectorType *SrcTy = dyn_cast<VectorType>(V->getType())) {
assert(DestPTy->getBitWidth() == SrcTy->getBitWidth() &&
"Not cast between same sized vectors!");
// First, check for null and undef
if (isa<UndefValue>(V))
return UndefValue::get(DestTy);
- if (const ConstantPacked *CP = dyn_cast<ConstantPacked>(V)) {
- // This is a cast from a ConstantPacked of one type to a
- // ConstantPacked of another type. Check to see if all elements of
+ if (const ConstantVector *CV = dyn_cast<ConstantVector>(V)) {
+ // This is a cast from a ConstantVector of one type to a
+ // ConstantVector of another type. Check to see if all elements of
// the input are simple.
bool AllSimpleConstants = true;
- for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i) {
- if (!isa<ConstantInt>(CP->getOperand(i)) &&
- !isa<ConstantFP>(CP->getOperand(i))) {
+ for (unsigned i = 0, e = CV->getNumOperands(); i != e; ++i) {
+ if (!isa<ConstantInt>(CV->getOperand(i)) &&
+ !isa<ConstantFP>(CV->getOperand(i))) {
AllSimpleConstants = false;
break;
}
// If all of the elements are simple constants, we can fold this.
if (AllSimpleConstants)
- return CastConstantPacked(const_cast<ConstantPacked*>(CP), DestPTy);
+ return CastConstantVector(const_cast<ConstantVector*>(CV), DestPTy);
}
}
}
// Handle integral constant input.
if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
- // Integral -> Integral, must be changing sign.
if (DestTy->isInteger())
- return ConstantInt::get(DestTy, CI->getZExtValue());
+ // Integral -> Integral. This is a no-op because the bit widths must
+ // be the same. Consequently, we just fold to V.
+ return const_cast<Constant*>(V);
if (DestTy->isFloatingPoint()) {
- if (DestTy == Type::FloatTy)
- return ConstantFP::get(DestTy, BitsToFloat(CI->getZExtValue()));
- assert(DestTy == Type::DoubleTy && "Unknown FP type!");
- return ConstantFP::get(DestTy, BitsToDouble(CI->getZExtValue()));
+ assert((DestTy == Type::DoubleTy || DestTy == Type::FloatTy) &&
+ "Unknown FP type!");
+ return ConstantFP::get(DestTy, APFloat(CI->getValue()));
}
- // Otherwise, can't fold this (packed?)
+ // Otherwise, can't fold this (vector?)
return 0;
}
// Handle ConstantFP input.
if (const ConstantFP *FP = dyn_cast<ConstantFP>(V)) {
// FP -> Integral.
- if (DestTy->isInteger()) {
- if (DestTy == Type::Int32Ty)
- return ConstantInt::get(DestTy, FloatToBits(FP->getValue()));
- assert(DestTy == Type::Int64Ty &&
- "Incorrect integer type for bitcast!");
- return ConstantInt::get(DestTy, DoubleToBits(FP->getValue()));
+ if (DestTy == Type::Int32Ty) {
+ return ConstantInt::get(FP->getValueAPF().convertToAPInt());
+ } else {
+ assert(DestTy == Type::Int64Ty && "only support f32/f64 for now!");
+ return ConstantInt::get(FP->getValueAPF().convertToAPInt());
}
}
return 0;
Constant *llvm::ConstantFoldExtractElementInstruction(const Constant *Val,
const Constant *Idx) {
if (isa<UndefValue>(Val)) // ee(undef, x) -> undef
- return UndefValue::get(cast<PackedType>(Val->getType())->getElementType());
+ return UndefValue::get(cast<VectorType>(Val->getType())->getElementType());
if (Val->isNullValue()) // ee(zero, x) -> zero
return Constant::getNullValue(
- cast<PackedType>(Val->getType())->getElementType());
+ cast<VectorType>(Val->getType())->getElementType());
- if (const ConstantPacked *CVal = dyn_cast<ConstantPacked>(Val)) {
+ if (const ConstantVector *CVal = dyn_cast<ConstantVector>(Val)) {
if (const ConstantInt *CIdx = dyn_cast<ConstantInt>(Idx)) {
return const_cast<Constant*>(CVal->getOperand(CIdx->getZExtValue()));
} else if (isa<UndefValue>(Idx)) {
const Constant *Idx) {
const ConstantInt *CIdx = dyn_cast<ConstantInt>(Idx);
if (!CIdx) return 0;
- uint64_t idxVal = CIdx->getZExtValue();
+ APInt idxVal = CIdx->getValue();
if (isa<UndefValue>(Val)) {
- // Insertion of scalar constant into packed undef
+ // Insertion of scalar constant into vector undef
// Optimize away insertion of undef
if (isa<UndefValue>(Elt))
return const_cast<Constant*>(Val);
// Otherwise break the aggregate undef into multiple undefs and do
// the insertion
unsigned numOps =
- cast<PackedType>(Val->getType())->getNumElements();
+ cast<VectorType>(Val->getType())->getNumElements();
std::vector<Constant*> Ops;
Ops.reserve(numOps);
for (unsigned i = 0; i < numOps; ++i) {
const Constant *Op =
- (i == idxVal) ? Elt : UndefValue::get(Elt->getType());
+ (idxVal == i) ? Elt : UndefValue::get(Elt->getType());
Ops.push_back(const_cast<Constant*>(Op));
}
- return ConstantPacked::get(Ops);
+ return ConstantVector::get(Ops);
}
if (isa<ConstantAggregateZero>(Val)) {
- // Insertion of scalar constant into packed aggregate zero
+ // Insertion of scalar constant into vector aggregate zero
// Optimize away insertion of zero
if (Elt->isNullValue())
return const_cast<Constant*>(Val);
// Otherwise break the aggregate zero into multiple zeros and do
// the insertion
unsigned numOps =
- cast<PackedType>(Val->getType())->getNumElements();
+ cast<VectorType>(Val->getType())->getNumElements();
std::vector<Constant*> Ops;
Ops.reserve(numOps);
for (unsigned i = 0; i < numOps; ++i) {
const Constant *Op =
- (i == idxVal) ? Elt : Constant::getNullValue(Elt->getType());
+ (idxVal == i) ? Elt : Constant::getNullValue(Elt->getType());
Ops.push_back(const_cast<Constant*>(Op));
}
- return ConstantPacked::get(Ops);
+ return ConstantVector::get(Ops);
}
- if (const ConstantPacked *CVal = dyn_cast<ConstantPacked>(Val)) {
- // Insertion of scalar constant into packed constant
+ if (const 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 =
- (i == idxVal) ? Elt : cast<Constant>(CVal->getOperand(i));
+ (idxVal == i) ? Elt : cast<Constant>(CVal->getOperand(i));
Ops.push_back(const_cast<Constant*>(Op));
}
- return ConstantPacked::get(Ops);
+ return ConstantVector::get(Ops);
}
return 0;
}
return 0;
}
-/// EvalVectorOp - Given two packed constants and a function pointer, apply the
-/// function pointer to each element pair, producing a new ConstantPacked
+/// EvalVectorOp - Given two vector constants and a function pointer, apply the
+/// function pointer to each element pair, producing a new ConstantVector
/// constant.
-static Constant *EvalVectorOp(const ConstantPacked *V1,
- const ConstantPacked *V2,
+static Constant *EvalVectorOp(const ConstantVector *V1,
+ const ConstantVector *V2,
Constant *(*FP)(Constant*, Constant*)) {
std::vector<Constant*> Res;
for (unsigned i = 0, e = V1->getNumOperands(); i != e; ++i)
Res.push_back(FP(const_cast<Constant*>(V1->getOperand(i)),
const_cast<Constant*>(V2->getOperand(i))));
- return ConstantPacked::get(Res);
+ return ConstantVector::get(Res);
}
Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode,
return Constant::getNullValue(C1->getType());
return const_cast<Constant*>(C2); // X / undef -> undef
case Instruction::Or: // X | undef -> -1
- if (const PackedType *PTy = dyn_cast<PackedType>(C1->getType()))
- return ConstantPacked::getAllOnesValue(PTy);
+ if (const VectorType *PTy = dyn_cast<VectorType>(C1->getType()))
+ return ConstantVector::getAllOnesValue(PTy);
return ConstantInt::getAllOnesValue(C1->getType());
case Instruction::LShr:
if (isa<UndefValue>(C2) && isa<UndefValue>(C1))
case Instruction::Mul:
if (C2->isNullValue()) return const_cast<Constant*>(C2); // X * 0 == 0
if (const ConstantInt *CI = dyn_cast<ConstantInt>(C2))
- if (CI->getZExtValue() == 1)
+ if (CI->equalsInt(1))
return const_cast<Constant*>(C1); // X * 1 == X
break;
case Instruction::UDiv:
case Instruction::SDiv:
if (const ConstantInt *CI = dyn_cast<ConstantInt>(C2))
- if (CI->getZExtValue() == 1)
+ if (CI->equalsInt(1))
return const_cast<Constant*>(C1); // X / 1 == X
break;
case Instruction::URem:
case Instruction::SRem:
if (const ConstantInt *CI = dyn_cast<ConstantInt>(C2))
- if (CI->getZExtValue() == 1)
+ if (CI->equalsInt(1))
return Constant::getNullValue(CI->getType()); // X % 1 == 0
break;
case Instruction::And:
- if (const ConstantInt *CI = dyn_cast<ConstantInt>(C2))
+ if (const ConstantInt *CI = dyn_cast<ConstantInt>(C2)) {
+ if (CI->isZero()) return const_cast<Constant*>(C2); // X & 0 == 0
if (CI->isAllOnesValue())
return const_cast<Constant*>(C1); // X & -1 == X
- if (C2->isNullValue()) return const_cast<Constant*>(C2); // X & 0 == 0
+
+ // (zext i32 to i64) & 4294967295 -> (zext i32 to i64)
+ if (CE1->getOpcode() == Instruction::ZExt) {
+ APInt PossiblySetBits
+ = cast<IntegerType>(CE1->getOperand(0)->getType())->getMask();
+ PossiblySetBits.zext(C1->getType()->getPrimitiveSizeInBits());
+ if ((PossiblySetBits & CI->getValue()) == PossiblySetBits)
+ return const_cast<Constant*>(C1);
+ }
+ }
if (CE1->isCast() && isa<GlobalValue>(CE1->getOperand(0))) {
GlobalValue *CPR = cast<GlobalValue>(CE1->getOperand(0));
// Functions are at least 4-byte aligned. If and'ing the address of a
// function with a constant < 4, fold it to zero.
if (const ConstantInt *CI = dyn_cast<ConstantInt>(C2))
- if (CI->getZExtValue() < 4 && isa<Function>(CPR))
+ if (CI->getValue().ult(APInt(CI->getType()->getBitWidth(),4)) &&
+ isa<Function>(CPR))
return Constant::getNullValue(CI->getType());
}
break;
case Instruction::Xor:
if (C2->isNullValue()) return const_cast<Constant*>(C1); // X ^ 0 == X
break;
+ case Instruction::AShr:
+ // ashr (zext C to Ty), C2 -> lshr (zext C, CSA), C2
+ if (CE1->getOpcode() == Instruction::ZExt) // Top bits known zero.
+ return ConstantExpr::getLShr(const_cast<Constant*>(C1),
+ const_cast<Constant*>(C2));
+ break;
}
}
} else if (isa<ConstantExpr>(C2)) {
// so look at directly computing the value.
if (const ConstantInt *CI1 = dyn_cast<ConstantInt>(C1)) {
if (const ConstantInt *CI2 = dyn_cast<ConstantInt>(C2)) {
- uint64_t C1Val = CI1->getZExtValue();
- uint64_t C2Val = CI2->getZExtValue();
+ using namespace APIntOps;
+ APInt C1V = CI1->getValue();
+ APInt C2V = CI2->getValue();
switch (Opcode) {
default:
break;
case Instruction::Add:
- return ConstantInt::get(C1->getType(), C1Val + C2Val);
+ return ConstantInt::get(C1V + C2V);
case Instruction::Sub:
- return ConstantInt::get(C1->getType(), C1Val - C2Val);
+ return ConstantInt::get(C1V - C2V);
case Instruction::Mul:
- return ConstantInt::get(C1->getType(), C1Val * C2Val);
+ return ConstantInt::get(C1V * C2V);
case Instruction::UDiv:
- if (CI2->isNullValue()) // X / 0 -> can't fold
- return 0;
- return ConstantInt::get(C1->getType(), C1Val / C2Val);
+ if (CI2->isNullValue())
+ return 0; // X / 0 -> can't fold
+ return ConstantInt::get(C1V.udiv(C2V));
case Instruction::SDiv:
- if (CI2->isNullValue()) return 0; // X / 0 -> can't fold
- if (CI2->isAllOnesValue() &&
- (((CI1->getType()->getPrimitiveSizeInBits() == 64) &&
- (CI1->getSExtValue() == INT64_MIN)) ||
- (CI1->getSExtValue() == -CI1->getSExtValue())))
- return 0; // MIN_INT / -1 -> overflow
- return ConstantInt::get(C1->getType(),
- CI1->getSExtValue() / CI2->getSExtValue());
- case Instruction::URem:
- if (C2->isNullValue()) return 0; // X / 0 -> can't fold
- return ConstantInt::get(C1->getType(), C1Val % C2Val);
+ if (CI2->isNullValue())
+ return 0; // X / 0 -> can't fold
+ if (C2V.isAllOnesValue() && C1V.isMinSignedValue())
+ return 0; // MIN_INT / -1 -> overflow
+ return ConstantInt::get(C1V.sdiv(C2V));
+ case Instruction::URem:
+ if (C2->isNullValue())
+ return 0; // X / 0 -> can't fold
+ return ConstantInt::get(C1V.urem(C2V));
case Instruction::SRem:
- if (CI2->isNullValue()) return 0; // X % 0 -> can't fold
- if (CI2->isAllOnesValue() &&
- (((CI1->getType()->getPrimitiveSizeInBits() == 64) &&
- (CI1->getSExtValue() == INT64_MIN)) ||
- (CI1->getSExtValue() == -CI1->getSExtValue())))
- return 0; // MIN_INT % -1 -> overflow
- return ConstantInt::get(C1->getType(),
- CI1->getSExtValue() % CI2->getSExtValue());
+ if (CI2->isNullValue())
+ return 0; // X % 0 -> can't fold
+ if (C2V.isAllOnesValue() && C1V.isMinSignedValue())
+ return 0; // MIN_INT % -1 -> overflow
+ return ConstantInt::get(C1V.srem(C2V));
case Instruction::And:
- return ConstantInt::get(C1->getType(), C1Val & C2Val);
+ return ConstantInt::get(C1V & C2V);
case Instruction::Or:
- return ConstantInt::get(C1->getType(), C1Val | C2Val);
+ return ConstantInt::get(C1V | C2V);
case Instruction::Xor:
- return ConstantInt::get(C1->getType(), C1Val ^ C2Val);
+ return ConstantInt::get(C1V ^ C2V);
case Instruction::Shl:
- return ConstantInt::get(C1->getType(), C1Val << C2Val);
+ if (uint32_t shiftAmt = C2V.getZExtValue())
+ if (shiftAmt < C1V.getBitWidth())
+ return ConstantInt::get(C1V.shl(shiftAmt));
+ else
+ return UndefValue::get(C1->getType()); // too big shift is undef
+ return const_cast<ConstantInt*>(CI1); // Zero shift is identity
case Instruction::LShr:
- return ConstantInt::get(C1->getType(), C1Val >> C2Val);
+ if (uint32_t shiftAmt = C2V.getZExtValue())
+ if (shiftAmt < C1V.getBitWidth())
+ return ConstantInt::get(C1V.lshr(shiftAmt));
+ else
+ return UndefValue::get(C1->getType()); // too big shift is undef
+ return const_cast<ConstantInt*>(CI1); // Zero shift is identity
case Instruction::AShr:
- return ConstantInt::get(C1->getType(),
- CI1->getSExtValue() >> C2Val);
+ if (uint32_t shiftAmt = C2V.getZExtValue())
+ if (shiftAmt < C1V.getBitWidth())
+ return ConstantInt::get(C1V.ashr(shiftAmt));
+ else
+ return UndefValue::get(C1->getType()); // too big shift is undef
+ return const_cast<ConstantInt*>(CI1); // Zero shift is identity
}
}
} else if (const ConstantFP *CFP1 = dyn_cast<ConstantFP>(C1)) {
if (const ConstantFP *CFP2 = dyn_cast<ConstantFP>(C2)) {
- double C1Val = CFP1->getValue();
- double C2Val = CFP2->getValue();
+ APFloat C1V = CFP1->getValueAPF();
+ APFloat C2V = CFP2->getValueAPF();
+ APFloat C3V = C1V; // copy for modification
+ bool isDouble = CFP1->getType()==Type::DoubleTy;
switch (Opcode) {
default:
break;
- case Instruction::Add:
- return ConstantFP::get(CFP1->getType(), C1Val + C2Val);
+ case Instruction::Add:
+ (void)C3V.add(C2V, APFloat::rmNearestTiesToEven);
+ return ConstantFP::get(CFP1->getType(), C3V);
case Instruction::Sub:
- return ConstantFP::get(CFP1->getType(), C1Val - C2Val);
- case Instruction::Mul:
- return ConstantFP::get(CFP1->getType(), C1Val * C2Val);
+ (void)C3V.subtract(C2V, APFloat::rmNearestTiesToEven);
+ return ConstantFP::get(CFP1->getType(), C3V);
+ case Instruction::Mul:
+ (void)C3V.multiply(C2V, APFloat::rmNearestTiesToEven);
+ return ConstantFP::get(CFP1->getType(), C3V);
case Instruction::FDiv:
- if (CFP2->isExactlyValue(0.0))
- return ConstantFP::get(CFP1->getType(),
- std::numeric_limits<double>::infinity());
- if (CFP2->isExactlyValue(-0.0))
- return ConstantFP::get(CFP1->getType(),
- -std::numeric_limits<double>::infinity());
- return ConstantFP::get(CFP1->getType(), C1Val / C2Val);
+ (void)C3V.divide(C2V, APFloat::rmNearestTiesToEven);
+ return ConstantFP::get(CFP1->getType(), C3V);
case Instruction::FRem:
- if (CFP2->isNullValue())
- return 0;
- return ConstantFP::get(CFP1->getType(), std::fmod(C1Val, C2Val));
+ if (C2V.isZero())
+ // IEEE 754, Section 7.1, #5
+ return ConstantFP::get(CFP1->getType(), isDouble ?
+ APFloat(std::numeric_limits<double>::quiet_NaN()) :
+ APFloat(std::numeric_limits<float>::quiet_NaN()));
+ (void)C3V.mod(C2V, APFloat::rmNearestTiesToEven);
+ return ConstantFP::get(CFP1->getType(), C3V);
}
}
- } else if (const ConstantPacked *CP1 = dyn_cast<ConstantPacked>(C1)) {
- if (const ConstantPacked *CP2 = dyn_cast<ConstantPacked>(C2)) {
+ } else if (const ConstantVector *CP1 = dyn_cast<ConstantVector>(C1)) {
+ if (const ConstantVector *CP2 = dyn_cast<ConstantVector>(C2)) {
switch (Opcode) {
default:
break;
Constant *C2 = const_cast<Constant*>(V2);
R = dyn_cast<ConstantInt>(
ConstantExpr::getFCmp(FCmpInst::FCMP_OEQ, C1, C2));
- if (R && R->getZExtValue())
+ if (R && !R->isZero())
return FCmpInst::FCMP_OEQ;
R = dyn_cast<ConstantInt>(
ConstantExpr::getFCmp(FCmpInst::FCMP_OLT, C1, C2));
- if (R && R->getZExtValue())
+ if (R && !R->isZero())
return FCmpInst::FCMP_OLT;
R = dyn_cast<ConstantInt>(
ConstantExpr::getFCmp(FCmpInst::FCMP_OGT, C1, C2));
- if (R && R->getZExtValue())
+ if (R && !R->isZero())
return FCmpInst::FCMP_OGT;
// Nothing more we can do
Constant *C2 = const_cast<Constant*>(V2);
ICmpInst::Predicate pred = ICmpInst::ICMP_EQ;
R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, C1, C2));
- if (R && R->getZExtValue())
+ if (R && !R->isZero())
return pred;
pred = isSigned ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT;
R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, C1, C2));
- if (R && R->getZExtValue())
+ if (R && !R->isZero())
return pred;
pred = isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT;
R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, C1, C2));
- if (R && R->getZExtValue())
+ if (R && !R->isZero())
return pred;
// If we couldn't figure it out, bail.
// Now we know that the RHS is a GlobalValue or simple constant,
// which (since the types must match) means that it's a ConstantPointerNull.
if (const GlobalValue *CPR2 = dyn_cast<GlobalValue>(V2)) {
- if (!CPR1->hasExternalWeakLinkage() || !CPR2->hasExternalWeakLinkage())
- return ICmpInst::ICMP_NE;
+ // Don't try to decide equality of aliases.
+ if (!isa<GlobalAlias>(CPR1) && !isa<GlobalAlias>(CPR2))
+ if (!CPR1->hasExternalWeakLinkage() || !CPR2->hasExternalWeakLinkage())
+ return ICmpInst::ICMP_NE;
} else {
- // GlobalVals can never be null.
assert(isa<ConstantPointerNull>(V2) && "Canonicalization guarantee!");
- if (!CPR1->hasExternalWeakLinkage())
+ // GlobalVals can never be null. Don't try to evaluate aliases.
+ if (!CPR1->hasExternalWeakLinkage() && !isa<GlobalAlias>(CPR1))
return ICmpInst::ICMP_NE;
}
} else {
// icmp eq/ne(null,GV) -> false/true
if (C1->isNullValue()) {
if (const GlobalValue *GV = dyn_cast<GlobalValue>(C2))
- if (!GV->hasExternalWeakLinkage()) // External weak GV can be null
+ // 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();
else if (pred == ICmpInst::ICMP_NE)
// icmp eq/ne(GV,null) -> false/true
} else if (C2->isNullValue()) {
if (const GlobalValue *GV = dyn_cast<GlobalValue>(C1))
- if (!GV->hasExternalWeakLinkage()) // External weak GV can be null
+ // 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();
else if (pred == ICmpInst::ICMP_NE)
}
if (isa<ConstantInt>(C1) && isa<ConstantInt>(C2)) {
- if (ICmpInst::isSignedPredicate(ICmpInst::Predicate(pred))) {
- int64_t V1 = cast<ConstantInt>(C1)->getSExtValue();
- int64_t V2 = cast<ConstantInt>(C2)->getSExtValue();
- switch (pred) {
- default: assert(0 && "Invalid ICmp Predicate"); return 0;
- case ICmpInst::ICMP_SLT:return ConstantInt::get(Type::Int1Ty, V1 < V2);
- case ICmpInst::ICMP_SGT:return ConstantInt::get(Type::Int1Ty, V1 > V2);
- case ICmpInst::ICMP_SLE:return ConstantInt::get(Type::Int1Ty, V1 <= V2);
- case ICmpInst::ICMP_SGE:return ConstantInt::get(Type::Int1Ty, V1 >= V2);
- }
- } else {
- uint64_t V1 = cast<ConstantInt>(C1)->getZExtValue();
- uint64_t V2 = cast<ConstantInt>(C2)->getZExtValue();
- 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_ULT:return ConstantInt::get(Type::Int1Ty, V1 < V2);
- case ICmpInst::ICMP_UGT:return ConstantInt::get(Type::Int1Ty, V1 > V2);
- case ICmpInst::ICMP_ULE:return ConstantInt::get(Type::Int1Ty, V1 <= V2);
- case ICmpInst::ICMP_UGE:return ConstantInt::get(Type::Int1Ty, V1 >= V2);
- }
+ 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));
}
} else if (isa<ConstantFP>(C1) && isa<ConstantFP>(C2)) {
- double C1Val = cast<ConstantFP>(C1)->getValue();
- double C2Val = cast<ConstantFP>(C2)->getValue();
+ 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();
case FCmpInst::FCMP_UNO:
- return ConstantInt::get(Type::Int1Ty, C1Val != C1Val || C2Val != C2Val);
+ return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpUnordered);
case FCmpInst::FCMP_ORD:
- return ConstantInt::get(Type::Int1Ty, C1Val == C1Val && C2Val == C2Val);
+ return ConstantInt::get(Type::Int1Ty, R!=APFloat::cmpUnordered);
case FCmpInst::FCMP_UEQ:
- if (C1Val != C1Val || C2Val != C2Val)
- return ConstantInt::getTrue();
- /* FALL THROUGH */
+ return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpUnordered ||
+ R==APFloat::cmpEqual);
case FCmpInst::FCMP_OEQ:
- return ConstantInt::get(Type::Int1Ty, C1Val == C2Val);
+ return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpEqual);
case FCmpInst::FCMP_UNE:
- if (C1Val != C1Val || C2Val != C2Val)
- return ConstantInt::getTrue();
- /* FALL THROUGH */
+ return ConstantInt::get(Type::Int1Ty, R!=APFloat::cmpEqual);
case FCmpInst::FCMP_ONE:
- return ConstantInt::get(Type::Int1Ty, C1Val != C2Val);
+ return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpLessThan ||
+ R==APFloat::cmpGreaterThan);
case FCmpInst::FCMP_ULT:
- if (C1Val != C1Val || C2Val != C2Val)
- return ConstantInt::getTrue();
- /* FALL THROUGH */
+ return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpUnordered ||
+ R==APFloat::cmpLessThan);
case FCmpInst::FCMP_OLT:
- return ConstantInt::get(Type::Int1Ty, C1Val < C2Val);
+ return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpLessThan);
case FCmpInst::FCMP_UGT:
- if (C1Val != C1Val || C2Val != C2Val)
- return ConstantInt::getTrue();
- /* FALL THROUGH */
+ return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpUnordered ||
+ R==APFloat::cmpGreaterThan);
case FCmpInst::FCMP_OGT:
- return ConstantInt::get(Type::Int1Ty, C1Val > C2Val);
+ return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpGreaterThan);
case FCmpInst::FCMP_ULE:
- if (C1Val != C1Val || C2Val != C2Val)
- return ConstantInt::getTrue();
- /* FALL THROUGH */
+ return ConstantInt::get(Type::Int1Ty, R!=APFloat::cmpGreaterThan);
case FCmpInst::FCMP_OLE:
- return ConstantInt::get(Type::Int1Ty, C1Val <= C2Val);
+ return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpLessThan ||
+ R==APFloat::cmpEqual);
case FCmpInst::FCMP_UGE:
- if (C1Val != C1Val || C2Val != C2Val)
- return ConstantInt::getTrue();
- /* FALL THROUGH */
+ return ConstantInt::get(Type::Int1Ty, R!=APFloat::cmpLessThan);
case FCmpInst::FCMP_OGE:
- return ConstantInt::get(Type::Int1Ty, C1Val >= C2Val);
+ return ConstantInt::get(Type::Int1Ty, R==APFloat::cmpGreaterThan ||
+ R==APFloat::cmpEqual);
}
- } else if (const ConstantPacked *CP1 = dyn_cast<ConstantPacked>(C1)) {
- if (const ConstantPacked *CP2 = dyn_cast<ConstantPacked>(C2)) {
+ } else if (const ConstantVector *CP1 = dyn_cast<ConstantVector>(C1)) {
+ if (const ConstantVector *CP2 = dyn_cast<ConstantVector>(C2)) {
if (pred == FCmpInst::FCMP_OEQ || pred == FCmpInst::FCMP_UEQ) {
for (unsigned i = 0, e = CP1->getNumOperands(); i != e; ++i) {
Constant *C= ConstantExpr::getFCmp(FCmpInst::FCMP_OEQ,
}
Constant *llvm::ConstantFoldGetElementPtr(const Constant *C,
- const std::vector<Value*> &IdxList) {
- if (IdxList.size() == 0 ||
- (IdxList.size() == 1 && cast<Constant>(IdxList[0])->isNullValue()))
+ Constant* const *Idxs,
+ unsigned NumIdx) {
+ if (NumIdx == 0 ||
+ (NumIdx == 1 && Idxs[0]->isNullValue()))
return const_cast<Constant*>(C);
if (isa<UndefValue>(C)) {
- const Type *Ty = GetElementPtrInst::getIndexedType(C->getType(), IdxList,
+ const Type *Ty = GetElementPtrInst::getIndexedType(C->getType(),
+ (Value **)Idxs,
+ (Value **)Idxs+NumIdx,
true);
assert(Ty != 0 && "Invalid indices for GEP!");
return UndefValue::get(PointerType::get(Ty));
}
- Constant *Idx0 = cast<Constant>(IdxList[0]);
+ Constant *Idx0 = Idxs[0];
if (C->isNullValue()) {
bool isNull = true;
- for (unsigned i = 0, e = IdxList.size(); i != e; ++i)
- if (!cast<Constant>(IdxList[i])->isNullValue()) {
+ for (unsigned i = 0, e = NumIdx; i != e; ++i)
+ if (!Idxs[i]->isNullValue()) {
isNull = false;
break;
}
if (isNull) {
- const Type *Ty = GetElementPtrInst::getIndexedType(C->getType(), IdxList,
+ const Type *Ty = GetElementPtrInst::getIndexedType(C->getType(),
+ (Value**)Idxs,
+ (Value**)Idxs+NumIdx,
true);
assert(Ty != 0 && "Invalid indices for GEP!");
return ConstantPointerNull::get(PointerType::get(Ty));
LastTy = *I;
if ((LastTy && isa<ArrayType>(LastTy)) || Idx0->isNullValue()) {
- std::vector<Value*> NewIndices;
- NewIndices.reserve(IdxList.size() + CE->getNumOperands());
+ SmallVector<Value*, 16> NewIndices;
+ NewIndices.reserve(NumIdx + CE->getNumOperands());
for (unsigned i = 1, e = CE->getNumOperands()-1; i != e; ++i)
NewIndices.push_back(CE->getOperand(i));
}
NewIndices.push_back(Combined);
- NewIndices.insert(NewIndices.end(), IdxList.begin()+1, IdxList.end());
- return ConstantExpr::getGetElementPtr(CE->getOperand(0), NewIndices);
+ NewIndices.insert(NewIndices.end(), Idxs+1, Idxs+NumIdx);
+ return ConstantExpr::getGetElementPtr(CE->getOperand(0), &NewIndices[0],
+ NewIndices.size());
}
}
// long 0, long 0)
// To: int* getelementptr ([3 x int]* %X, long 0, long 0)
//
- if (CE->isCast() && IdxList.size() > 1 && Idx0->isNullValue())
+ if (CE->isCast() && NumIdx > 1 && Idx0->isNullValue()) {
if (const PointerType *SPT =
dyn_cast<PointerType>(CE->getOperand(0)->getType()))
if (const ArrayType *SAT = dyn_cast<ArrayType>(SPT->getElementType()))
dyn_cast<ArrayType>(cast<PointerType>(C->getType())->getElementType()))
if (CAT->getElementType() == SAT->getElementType())
return ConstantExpr::getGetElementPtr(
- (Constant*)CE->getOperand(0), IdxList);
+ (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) {
+ Constant *Base = CE->getOperand(0);
+ Constant *Offset = Idxs[0];
+
+ // Convert the smaller integer to the larger type.
+ if (Offset->getType()->getPrimitiveSizeInBits() <
+ Base->getType()->getPrimitiveSizeInBits())
+ Offset = ConstantExpr::getSExt(Offset, Base->getType());
+ else if (Base->getType()->getPrimitiveSizeInBits() <
+ Offset->getType()->getPrimitiveSizeInBits())
+ Base = ConstantExpr::getZExt(Base, Base->getType());
+
+ Base = ConstantExpr::getAdd(Base, Offset);
+ return ConstantExpr::getIntToPtr(Base, CE->getType());
+ }
}
return 0;
}
projects / oota-llvm.git / blobdiff