#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Operator.h"
+#include "llvm/IR/PatternMatch.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MathExtras.h"
#include <limits>
using namespace llvm;
+using namespace llvm::PatternMatch;
//===----------------------------------------------------------------------===//
// ConstantFold*Instruction Implementations
// Analysis/ConstantFolding.cpp
unsigned NumElts = DstTy->getNumElements();
if (NumElts != CV->getType()->getVectorNumElements())
- return 0;
+ return nullptr;
Type *DstEltTy = DstTy->getElementType();
// Let CastInst::isEliminableCastPair do the heavy lifting.
return CastInst::isEliminableCastPair(firstOp, secondOp, SrcTy, MidTy, DstTy,
- 0, FakeIntPtrTy, 0);
+ nullptr, FakeIntPtrTy, nullptr);
}
static Constant *FoldBitCast(Constant *V, Type *DestTy) {
if (ElTy == DPTy->getElementType())
// This GEP is inbounds because all indices are zero.
- return ConstantExpr::getInBoundsGetElementPtr(V, IdxList);
+ return ConstantExpr::getInBoundsGetElementPtr(PTy->getElementType(),
+ V, IdxList);
}
// Handle casts from one vector constant to another. We know that the src
if (VectorType *SrcTy = dyn_cast<VectorType>(V->getType())) {
assert(DestPTy->getBitWidth() == SrcTy->getBitWidth() &&
"Not cast between same sized vectors!");
- SrcTy = NULL;
+ SrcTy = nullptr;
// First, check for null. Undef is already handled.
if (isa<ConstantAggregateZero>(V))
return Constant::getNullValue(DestTy);
// be the same. Consequently, we just fold to V.
return V;
- if (DestTy->isFloatingPointTy())
+ // See note below regarding the PPC_FP128 restriction.
+ if (DestTy->isFloatingPointTy() && !DestTy->isPPC_FP128Ty())
return ConstantFP::get(DestTy->getContext(),
APFloat(DestTy->getFltSemantics(),
CI->getValue()));
// Otherwise, can't fold this (vector?)
- return 0;
+ return nullptr;
}
// Handle ConstantFP input: FP -> Integral.
- if (ConstantFP *FP = dyn_cast<ConstantFP>(V))
+ if (ConstantFP *FP = dyn_cast<ConstantFP>(V)) {
+ // PPC_FP128 is really the sum of two consecutive doubles, where the first
+ // double is always stored first in memory, regardless of the target
+ // endianness. The memory layout of i128, however, depends on the target
+ // endianness, and so we can't fold this without target endianness
+ // information. This should instead be handled by
+ // Analysis/ConstantFolding.cpp
+ if (FP->getType()->isPPC_FP128Ty())
+ return nullptr;
+
return ConstantInt::get(FP->getContext(),
FP->getValueAPF().bitcastToAPInt());
+ }
- return 0;
+ return nullptr;
}
// In the input is a constant expr, we might be able to recursively simplify.
// If not, we definitely can't do anything.
ConstantExpr *CE = dyn_cast<ConstantExpr>(C);
- if (CE == 0) return 0;
-
+ if (!CE) return nullptr;
+
switch (CE->getOpcode()) {
- default: return 0;
+ default: return nullptr;
case Instruction::Or: {
Constant *RHS = ExtractConstantBytes(CE->getOperand(1), ByteStart,ByteSize);
- if (RHS == 0)
- return 0;
+ if (!RHS)
+ return nullptr;
// X | -1 -> -1.
if (ConstantInt *RHSC = dyn_cast<ConstantInt>(RHS))
return RHSC;
Constant *LHS = ExtractConstantBytes(CE->getOperand(0), ByteStart,ByteSize);
- if (LHS == 0)
- return 0;
+ if (!LHS)
+ return nullptr;
return ConstantExpr::getOr(LHS, RHS);
}
case Instruction::And: {
Constant *RHS = ExtractConstantBytes(CE->getOperand(1), ByteStart,ByteSize);
- if (RHS == 0)
- return 0;
+ if (!RHS)
+ return nullptr;
// X & 0 -> 0.
if (RHS->isNullValue())
return RHS;
Constant *LHS = ExtractConstantBytes(CE->getOperand(0), ByteStart,ByteSize);
- if (LHS == 0)
- return 0;
+ if (!LHS)
+ return nullptr;
return ConstantExpr::getAnd(LHS, RHS);
}
case Instruction::LShr: {
ConstantInt *Amt = dyn_cast<ConstantInt>(CE->getOperand(1));
- if (Amt == 0)
- return 0;
+ if (!Amt)
+ return nullptr;
unsigned ShAmt = Amt->getZExtValue();
// Cannot analyze non-byte shifts.
if ((ShAmt & 7) != 0)
- return 0;
+ return nullptr;
ShAmt >>= 3;
// If the extract is known to be all zeros, return zero.
return ExtractConstantBytes(CE->getOperand(0), ByteStart+ShAmt, ByteSize);
// TODO: Handle the 'partially zero' case.
- return 0;
+ return nullptr;
}
case Instruction::Shl: {
ConstantInt *Amt = dyn_cast<ConstantInt>(CE->getOperand(1));
- if (Amt == 0)
- return 0;
+ if (!Amt)
+ return nullptr;
unsigned ShAmt = Amt->getZExtValue();
// Cannot analyze non-byte shifts.
if ((ShAmt & 7) != 0)
- return 0;
+ return nullptr;
ShAmt >>= 3;
// If the extract is known to be all zeros, return zero.
return ExtractConstantBytes(CE->getOperand(0), ByteStart-ShAmt, ByteSize);
// TODO: Handle the 'partially zero' case.
- return 0;
+ return nullptr;
}
case Instruction::ZExt: {
}
// TODO: Handle the 'partially zero' case.
- return 0;
+ return nullptr;
}
}
}
// If there's no interesting folding happening, bail so that we don't create
// a constant that looks like it needs folding but really doesn't.
if (!Folded)
- return 0;
+ return nullptr;
// Base case: Get a regular sizeof expression.
Constant *C = ConstantExpr::getSizeOf(Ty);
// If there's no interesting folding happening, bail so that we don't create
// a constant that looks like it needs folding but really doesn't.
if (!Folded)
- return 0;
+ return nullptr;
// Base case: Get a regular alignof expression.
Constant *C = ConstantExpr::getAlignOf(Ty);
unsigned NumElems = STy->getNumElements();
// An empty struct has no members.
if (NumElems == 0)
- return 0;
+ return nullptr;
// Check for a struct with all members having the same size.
Constant *MemberSize =
getFoldedSizeOf(STy->getElementType(0), DestTy, true);
// If there's no interesting folding happening, bail so that we don't create
// a constant that looks like it needs folding but really doesn't.
if (!Folded)
- return 0;
+ return nullptr;
// Base case: Get a regular offsetof expression.
Constant *C = ConstantExpr::getOffsetOf(Ty, FieldNo);
// Try hard to fold cast of cast because they are often eliminable.
if (unsigned newOpc = foldConstantCastPair(opc, CE, DestTy))
return ConstantExpr::getCast(newOpc, CE->getOperand(0), DestTy);
- } else if (CE->getOpcode() == Instruction::GetElementPtr) {
+ } else if (CE->getOpcode() == Instruction::GetElementPtr &&
+ // Do not fold addrspacecast (gep 0, .., 0). It might make the
+ // addrspacecast uncanonicalized.
+ opc != Instruction::AddrSpaceCast) {
// If all of the indexes in the GEP are null values, there is no pointer
// adjustment going on. We might as well cast the source pointer.
bool isAllNull = true;
APFloat::rmNearestTiesToEven, &ignored);
return ConstantFP::get(V->getContext(), Val);
}
- return 0; // Can't fold.
+ return nullptr; // Can't fold.
case Instruction::FPToUI:
case Instruction::FPToSI:
if (ConstantFP *FPC = dyn_cast<ConstantFP>(V)) {
bool ignored;
uint64_t x[2];
uint32_t DestBitWidth = cast<IntegerType>(DestTy)->getBitWidth();
- (void) V.convertToInteger(x, DestBitWidth, opc==Instruction::FPToSI,
- APFloat::rmTowardZero, &ignored);
+ if (APFloat::opInvalidOp ==
+ V.convertToInteger(x, DestBitWidth, opc==Instruction::FPToSI,
+ APFloat::rmTowardZero, &ignored)) {
+ // Undefined behavior invoked - the destination type can't represent
+ // the input constant.
+ return UndefValue::get(DestTy);
+ }
APInt Val(DestBitWidth, x);
return ConstantInt::get(FPC->getContext(), Val);
}
- return 0; // Can't fold.
+ return nullptr; // Can't fold.
case Instruction::IntToPtr: //always treated as unsigned
if (V->isNullValue()) // Is it an integral null value?
return ConstantPointerNull::get(cast<PointerType>(DestTy));
- return 0; // Other pointer types cannot be casted
+ return nullptr; // Other pointer types cannot be casted
case Instruction::PtrToInt: // always treated as unsigned
// Is it a null pointer value?
if (V->isNullValue())
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
if (CE->getOpcode() == Instruction::GetElementPtr &&
CE->getOperand(0)->isNullValue()) {
- Type *Ty =
- cast<PointerType>(CE->getOperand(0)->getType())->getElementType();
+ GEPOperator *GEPO = cast<GEPOperator>(CE);
+ Type *Ty = GEPO->getSourceElementType();
if (CE->getNumOperands() == 2) {
// Handle a sizeof-like expression.
Constant *Idx = CE->getOperand(1);
}
}
// Other pointer types cannot be casted
- return 0;
+ return nullptr;
case Instruction::UIToFP:
case Instruction::SIToFP:
if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
APInt api = CI->getValue();
APFloat apf(DestTy->getFltSemantics(),
APInt::getNullValue(DestTy->getPrimitiveSizeInBits()));
- (void)apf.convertFromAPInt(api,
- opc==Instruction::SIToFP,
- APFloat::rmNearestTiesToEven);
+ if (APFloat::opOverflow &
+ apf.convertFromAPInt(api, opc==Instruction::SIToFP,
+ APFloat::rmNearestTiesToEven)) {
+ // Undefined behavior invoked - the destination type can't represent
+ // the input constant.
+ return UndefValue::get(DestTy);
+ }
return ConstantFP::get(V->getContext(), apf);
}
- return 0;
+ return nullptr;
case Instruction::ZExt:
if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
uint32_t BitWidth = cast<IntegerType>(DestTy)->getBitWidth();
return ConstantInt::get(V->getContext(),
CI->getValue().zext(BitWidth));
}
- return 0;
+ return nullptr;
case Instruction::SExt:
if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
uint32_t BitWidth = cast<IntegerType>(DestTy)->getBitWidth();
return ConstantInt::get(V->getContext(),
CI->getValue().sext(BitWidth));
}
- return 0;
+ return nullptr;
case Instruction::Trunc: {
+ if (V->getType()->isVectorTy())
+ return nullptr;
+
uint32_t DestBitWidth = cast<IntegerType>(DestTy)->getBitWidth();
if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
return ConstantInt::get(V->getContext(),
if (Constant *Res = ExtractConstantBytes(V, 0, DestBitWidth / 8))
return Res;
- return 0;
+ return nullptr;
}
case Instruction::BitCast:
return FoldBitCast(V, DestTy);
case Instruction::AddrSpaceCast:
- return 0;
+ return nullptr;
}
}
return ConstantExpr::getSelect(Cond, V1, FalseVal->getOperand(2));
}
- return 0;
+ return nullptr;
}
Constant *llvm::ConstantFoldExtractElementInstruction(Constant *Val,
return UndefValue::get(Val->getType()->getVectorElementType());
if (ConstantInt *CIdx = dyn_cast<ConstantInt>(Idx)) {
- uint64_t Index = CIdx->getZExtValue();
// ee({w,x,y,z}, wrong_value) -> undef
- if (Index >= Val->getType()->getVectorNumElements())
+ if (CIdx->uge(Val->getType()->getVectorNumElements()))
return UndefValue::get(Val->getType()->getVectorElementType());
- return Val->getAggregateElement(Index);
+ return Val->getAggregateElement(CIdx->getZExtValue());
}
- return 0;
+ return nullptr;
}
Constant *llvm::ConstantFoldInsertElementInstruction(Constant *Val,
Constant *Elt,
Constant *Idx) {
+ if (isa<UndefValue>(Idx))
+ return UndefValue::get(Val->getType());
+
ConstantInt *CIdx = dyn_cast<ConstantInt>(Idx);
- if (!CIdx) return 0;
- const APInt &IdxVal = CIdx->getValue();
-
+ if (!CIdx) return nullptr;
+
+ unsigned NumElts = Val->getType()->getVectorNumElements();
+ if (CIdx->uge(NumElts))
+ return UndefValue::get(Val->getType());
+
SmallVector<Constant*, 16> Result;
- Type *Ty = IntegerType::get(Val->getContext(), 32);
- for (unsigned i = 0, e = Val->getType()->getVectorNumElements(); i != e; ++i){
+ Result.reserve(NumElts);
+ auto *Ty = Type::getInt32Ty(Val->getContext());
+ uint64_t IdxVal = CIdx->getZExtValue();
+ for (unsigned i = 0; i != NumElts; ++i) {
if (i == IdxVal) {
Result.push_back(Elt);
continue;
}
- Constant *C =
- ConstantExpr::getExtractElement(Val, ConstantInt::get(Ty, i));
+ Constant *C = ConstantExpr::getExtractElement(Val, ConstantInt::get(Ty, i));
Result.push_back(C);
}
-
+
return ConstantVector::get(Result);
}
return UndefValue::get(VectorType::get(EltTy, MaskNumElts));
// Don't break the bitcode reader hack.
- if (isa<ConstantExpr>(Mask)) return 0;
+ if (isa<ConstantExpr>(Mask)) return nullptr;
unsigned SrcNumElts = V1->getType()->getVectorNumElements();
if (Constant *C = Agg->getAggregateElement(Idxs[0]))
return ConstantFoldExtractValueInstruction(C, Idxs.slice(1));
- return 0;
+ return nullptr;
}
Constant *llvm::ConstantFoldInsertValueInstruction(Constant *Agg,
SmallVector<Constant*, 32> Result;
for (unsigned i = 0; i != NumElts; ++i) {
Constant *C = Agg->getAggregateElement(i);
- if (C == 0) return 0;
-
+ if (!C) return nullptr;
+
if (Idxs[0] == i)
C = ConstantFoldInsertValueInstruction(C, Val, Idxs.slice(1));
return C1;
return Constant::getNullValue(C1->getType()); // undef & X -> 0
case Instruction::Mul: {
- ConstantInt *CI;
- // X * undef -> undef if X is odd or undef
- if (((CI = dyn_cast<ConstantInt>(C1)) && CI->getValue()[0]) ||
- ((CI = dyn_cast<ConstantInt>(C2)) && CI->getValue()[0]) ||
- (isa<UndefValue>(C1) && isa<UndefValue>(C2)))
- return UndefValue::get(C1->getType());
+ // undef * undef -> undef
+ if (isa<UndefValue>(C1) && isa<UndefValue>(C2))
+ return C1;
+ const APInt *CV;
+ // X * undef -> undef if X is odd
+ if (match(C1, m_APInt(CV)) || match(C2, m_APInt(CV)))
+ if ((*CV)[0])
+ return UndefValue::get(C1->getType());
// X * undef -> 0 otherwise
return Constant::getNullValue(C1->getType());
}
- case Instruction::UDiv:
case Instruction::SDiv:
+ case Instruction::UDiv:
+ // X / undef -> undef
+ if (match(C1, m_Zero()))
+ return C2;
+ // undef / 0 -> undef
// undef / 1 -> undef
- if (Opcode == Instruction::UDiv || Opcode == Instruction::SDiv)
- if (ConstantInt *CI2 = dyn_cast<ConstantInt>(C2))
- if (CI2->isOne())
- return C1;
- // FALL THROUGH
+ if (match(C2, m_Zero()) || match(C2, m_One()))
+ return C1;
+ // undef / X -> 0 otherwise
+ return Constant::getNullValue(C1->getType());
case Instruction::URem:
case Instruction::SRem:
- if (!isa<UndefValue>(C2)) // undef / X -> 0
- return Constant::getNullValue(C1->getType());
- return C2; // X / undef -> undef
+ // X % undef -> undef
+ if (match(C2, m_Undef()))
+ return C2;
+ // undef % 0 -> undef
+ if (match(C2, m_Zero()))
+ return C1;
+ // undef % X -> 0 otherwise
+ return Constant::getNullValue(C1->getType());
case Instruction::Or: // X | undef -> -1
if (isa<UndefValue>(C1) && isa<UndefValue>(C2)) // undef | undef -> undef
return C1;
return Constant::getAllOnesValue(C1->getType()); // undef | X -> ~0
case Instruction::LShr:
- if (isa<UndefValue>(C2) && isa<UndefValue>(C1))
- return C1; // undef lshr undef -> undef
- return Constant::getNullValue(C1->getType()); // X lshr undef -> 0
- // undef lshr X -> 0
+ // X >>l undef -> undef
+ if (isa<UndefValue>(C2))
+ return C2;
+ // undef >>l 0 -> undef
+ if (match(C2, m_Zero()))
+ return C1;
+ // undef >>l X -> 0
+ return Constant::getNullValue(C1->getType());
case Instruction::AShr:
- if (!isa<UndefValue>(C2)) // undef ashr X --> all ones
- return Constant::getAllOnesValue(C1->getType());
- else if (isa<UndefValue>(C1))
- return C1; // undef ashr undef -> undef
- else
- return C1; // X ashr undef --> X
+ // X >>a undef -> undef
+ if (isa<UndefValue>(C2))
+ return C2;
+ // undef >>a 0 -> undef
+ if (match(C2, m_Zero()))
+ return C1;
+ // TODO: undef >>a X -> undef if the shift is exact
+ // undef >>a X -> 0
+ return Constant::getNullValue(C1->getType());
case Instruction::Shl:
- if (isa<UndefValue>(C2) && isa<UndefValue>(C1))
- return C1; // undef shl undef -> undef
- // undef << X -> 0 or X << undef -> 0
+ // X << undef -> undef
+ if (isa<UndefValue>(C2))
+ return C2;
+ // undef << 0 -> undef
+ if (match(C2, m_Zero()))
+ return C1;
+ // undef << X -> 0
return Constant::getNullValue(C1->getType());
}
}
return ConstantInt::get(CI1->getContext(), C1V | C2V);
case Instruction::Xor:
return ConstantInt::get(CI1->getContext(), C1V ^ C2V);
- case Instruction::Shl: {
- uint32_t shiftAmt = C2V.getZExtValue();
- if (shiftAmt < C1V.getBitWidth())
- return ConstantInt::get(CI1->getContext(), 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(CI1->getContext(), 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(CI1->getContext(), C1V.ashr(shiftAmt));
- else
- return UndefValue::get(C1->getType()); // too big shift is undef
- }
+ case Instruction::Shl:
+ if (C2V.ult(C1V.getBitWidth()))
+ return ConstantInt::get(CI1->getContext(), C1V.shl(C2V));
+ return UndefValue::get(C1->getType()); // too big shift is undef
+ case Instruction::LShr:
+ if (C2V.ult(C1V.getBitWidth()))
+ return ConstantInt::get(CI1->getContext(), C1V.lshr(C2V));
+ return UndefValue::get(C1->getType()); // too big shift is undef
+ case Instruction::AShr:
+ if (C2V.ult(C1V.getBitWidth()))
+ return ConstantInt::get(CI1->getContext(), C1V.ashr(C2V));
+ return UndefValue::get(C1->getType()); // too big shift is undef
}
}
}
// We don't know how to fold this.
- return 0;
+ return nullptr;
}
/// isZeroSizedType - This type is zero sized if its an array or structure of
if (!isa<ConstantInt>(C1) || !isa<ConstantInt>(C2))
return -2; // don't know!
- // 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()->isIntegerTy(64))
- C1 = ConstantExpr::getSExt(C1, Type::getInt64Ty(C1->getContext()));
+ // We cannot compare the indices if they don't fit in an int64_t.
+ if (cast<ConstantInt>(C1)->getValue().getActiveBits() > 64 ||
+ cast<ConstantInt>(C2)->getValue().getActiveBits() > 64)
+ return -2; // don't know!
- if (!C2->getType()->isIntegerTy(64))
- C2 = ConstantExpr::getSExt(C2, Type::getInt64Ty(C1->getContext()));
+ // Ok, we have two differing integer indices. Sign extend them to be the same
+ // type.
+ int64_t C1Val = cast<ConstantInt>(C1)->getSExtValue();
+ int64_t C2Val = cast<ConstantInt>(C2)->getSExtValue();
- if (C1 == C2) return 0; // They are equal
+ if (C1Val == C2Val) return 0; // They are equal
// If the type being indexed over is really just a zero sized type, there is
// no pointer difference being made here.
// If they are really different, now that they are the same type, then we
// found a difference!
- if (cast<ConstantInt>(C1)->getSExtValue() <
- cast<ConstantInt>(C2)->getSExtValue())
+ if (C1Val < C2Val)
return -1;
else
return 1;
if (!isa<ConstantExpr>(V1)) {
if (!isa<ConstantExpr>(V2)) {
- // We distilled thisUse the standard constant folder for a few cases
- ConstantInt *R = 0;
+ // Simple case, use the standard constant folder.
+ ConstantInt *R = nullptr;
R = dyn_cast<ConstantInt>(
ConstantExpr::getFCmp(FCmpInst::FCMP_OEQ, V1, V2));
if (R && !R->isZero())
return FCmpInst::BAD_FCMP_PREDICATE;
}
+static ICmpInst::Predicate areGlobalsPotentiallyEqual(const GlobalValue *GV1,
+ const GlobalValue *GV2) {
+ auto isGlobalUnsafeForEquality = [](const GlobalValue *GV) {
+ if (GV->hasExternalWeakLinkage() || GV->hasWeakAnyLinkage())
+ return true;
+ if (const auto *GVar = dyn_cast<GlobalVariable>(GV)) {
+ Type *Ty = GVar->getValueType();
+ // A global with opaque type might end up being zero sized.
+ if (!Ty->isSized())
+ return true;
+ // A global with an empty type might lie at the address of any other
+ // global.
+ if (Ty->isEmptyTy())
+ return true;
+ }
+ return false;
+ };
+ // Don't try to decide equality of aliases.
+ if (!isa<GlobalAlias>(GV1) && !isa<GlobalAlias>(GV2))
+ if (!isGlobalUnsafeForEquality(GV1) && !isGlobalUnsafeForEquality(GV2))
+ return ICmpInst::ICMP_NE;
+ return ICmpInst::BAD_ICMP_PREDICATE;
+}
+
/// evaluateICmpRelation - This function determines if there is anything we can
/// decide about the two constants provided. This doesn't need to handle simple
/// things like integer comparisons, but should instead handle ConstantExprs
!isa<BlockAddress>(V2)) {
// We distilled this down to a simple case, use the standard constant
// folder.
- ConstantInt *R = 0;
+ ConstantInt *R = nullptr;
ICmpInst::Predicate pred = ICmpInst::ICMP_EQ;
R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, V1, V2));
if (R && !R->isZero())
// constant (which, since the types must match, means that it's a
// ConstantPointerNull).
if (const GlobalValue *GV2 = dyn_cast<GlobalValue>(V2)) {
- // Don't try to decide equality of aliases.
- if (!isa<GlobalAlias>(GV) && !isa<GlobalAlias>(GV2))
- if (!GV->hasExternalWeakLinkage() || !GV2->hasExternalWeakLinkage())
- return ICmpInst::ICMP_NE;
+ return areGlobalsPotentiallyEqual(GV, GV2);
} else if (isa<BlockAddress>(V2)) {
return ICmpInst::ICMP_NE; // Globals never equal labels.
} else {
}
break;
- case Instruction::GetElementPtr:
+ case Instruction::GetElementPtr: {
+ GEPOperator *CE1GEP = cast<GEPOperator>(CE1);
// Ok, since this is a getelementptr, we know that the constant has a
// pointer type. Check the various cases.
if (isa<ConstantPointerNull>(V2)) {
"Surprising getelementptr!");
return isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT;
} else {
- // If they are different globals, we don't know what the value is.
+ if (CE1GEP->hasAllZeroIndices())
+ return areGlobalsPotentiallyEqual(GV, GV2);
return ICmpInst::BAD_ICMP_PREDICATE;
}
}
// By far the most common case to handle is when the base pointers are
// obviously to the same global.
if (isa<GlobalValue>(CE1Op0) && isa<GlobalValue>(CE2Op0)) {
- if (CE1Op0 != CE2Op0) // Don't know relative ordering.
+ // Don't know relative ordering, but check for inequality.
+ if (CE1Op0 != CE2Op0) {
+ GEPOperator *CE2GEP = cast<GEPOperator>(CE2);
+ if (CE1GEP->hasAllZeroIndices() && CE2GEP->hasAllZeroIndices())
+ return areGlobalsPotentiallyEqual(cast<GlobalValue>(CE1Op0),
+ cast<GlobalValue>(CE2Op0));
return ICmpInst::BAD_ICMP_PREDICATE;
+ }
// Ok, we know that both getelementptr instructions are based on the
// same global. From this, we can precisely determine the relative
// ordering of the resultant pointers.
}
}
}
+ }
default:
break;
}
// Handle some degenerate cases first
if (isa<UndefValue>(C1) || isa<UndefValue>(C2)) {
+ CmpInst::Predicate Predicate = CmpInst::Predicate(pred);
+ bool isIntegerPredicate = ICmpInst::isIntPredicate(Predicate);
// For EQ and NE, we can always pick a value for the undef to make the
// predicate pass or fail, so we can return undef.
- // Also, if both operands are undef, we can return undef.
- if (ICmpInst::isEquality(ICmpInst::Predicate(pred)) ||
- (isa<UndefValue>(C1) && isa<UndefValue>(C2)))
+ // Also, if both operands are undef, we can return undef for int comparison.
+ if (ICmpInst::isEquality(Predicate) || (isIntegerPredicate && C1 == C2))
return UndefValue::get(ResultTy);
- // Otherwise, pick the same value as the non-undef operand, and fold
- // it to true or false.
- return ConstantInt::get(ResultTy, CmpInst::isTrueWhenEqual(pred));
+
+ // Otherwise, for integer compare, pick the same value as the non-undef
+ // operand, and fold it to true or false.
+ if (isIntegerPredicate)
+ return ConstantInt::get(ResultTy, CmpInst::isTrueWhenEqual(pred));
+
+ // Choosing NaN for the undef will always make unordered comparison succeed
+ // and ordered comparison fails.
+ return ConstantInt::get(ResultTy, CmpInst::isUnordered(Predicate));
}
// icmp eq/ne(null,GV) -> false/true
return ConstantVector::get(ResElts);
}
- if (C1->getType()->isFloatingPointTy()) {
+ if (C1->getType()->isFloatingPointTy() &&
+ // Only call evaluateFCmpRelation if we have a constant expr to avoid
+ // infinite recursive loop
+ (isa<ConstantExpr>(C1) || isa<ConstantExpr>(C2))) {
int Result = -1; // -1 = unknown, 0 = known false, 1 = known true.
switch (evaluateFCmpRelation(C1, C2)) {
default: llvm_unreachable("Unknown relation!");
return ConstantExpr::getICmp(pred, C2, C1);
}
}
- return 0;
+ return nullptr;
}
/// isInBoundsIndices - Test whether the given sequence of *normalized* indices
}
/// \brief Test whether a given ConstantInt is in-range for a SequentialType.
-static bool isIndexInRangeOfSequentialType(const SequentialType *STy,
+static bool isIndexInRangeOfSequentialType(SequentialType *STy,
const ConstantInt *CI) {
- if (const PointerType *PTy = dyn_cast<PointerType>(STy))
- // Only handle pointers to sized types, not pointers to functions.
- return PTy->getElementType()->isSized();
+ if (isa<PointerType>(STy))
+ return true;
uint64_t NumElements = 0;
// Determine the number of elements in our sequential type.
- if (
const ArrayType *ATy = dyn_cast<ArrayType>(STy))
+ if (
auto *ATy = dyn_cast<ArrayType>(STy))
NumElements = ATy->getNumElements();
- else if (const VectorType *VTy = dyn_cast<VectorType>(STy))
+ else if (auto *VTy = dyn_cast<VectorType>(STy))
NumElements = VTy->getNumElements();
assert((isa<ArrayType>(STy) || NumElements > 0) &&
}
template<typename IndexTy>
-static Constant *ConstantFoldGetElementPtrImpl(Constant *C,
+static Constant *ConstantFoldGetElementPtrImpl(Type *PointeeTy, Constant *C,
bool inBounds,
ArrayRef<IndexTy> Idxs) {
if (Idxs.empty()) return C;
if (isa<UndefValue>(C)) {
PointerType *Ptr = cast<PointerType>(C->getType());
- Type *Ty = GetElementPtrInst::getIndexedType(Ptr, Idxs);
- assert(Ty != 0 && "Invalid indices for GEP!");
+ Type *Ty = GetElementPtrInst::getIndexedType(
+ cast<PointerType>(Ptr->getScalarType())->getElementType(), Idxs);
+ assert(Ty && "Invalid indices for GEP!");
return UndefValue::get(PointerType::get(Ty, Ptr->getAddressSpace()));
}
}
if (isNull) {
PointerType *Ptr = cast<PointerType>(C->getType());
- Type *Ty = GetElementPtrInst::getIndexedType(Ptr, Idxs);
- assert(Ty != 0 && "Invalid indices for GEP!");
+ Type *Ty = GetElementPtrInst::getIndexedType(
+ cast<PointerType>(Ptr->getScalarType())->getElementType(), Idxs);
+ assert(Ty && "Invalid indices for GEP!");
return ConstantPointerNull::get(PointerType::get(Ty,
Ptr->getAddressSpace()));
}
// getelementptr instructions into a single instruction.
//
if (CE->getOpcode() == Instruction::GetElementPtr) {
- Type *LastTy = 0;
+ Type *LastTy = nullptr;
for (gep_type_iterator I = gep_type_begin(CE), E = gep_type_end(CE);
I != E; ++I)
LastTy = *I;
if (PerformFold) {
SmallVector<Value*, 16> NewIndices;
NewIndices.reserve(Idxs.size() + CE->getNumOperands());
- for (unsigned i = 1, e = CE->getNumOperands()-1; i != e; ++i)
- NewIndices.push_back(CE->getOperand(i));
+ NewIndices.append(CE->op_begin() + 1, CE->op_end() - 1);
// Add the last index of the source with the first index of the new GEP.
// Make sure to handle the case when they are actually different types.
if (!Idx0->isNullValue()) {
Type *IdxTy = Combined->getType();
if (IdxTy != Idx0->getType()) {
- Type *Int64Ty = Type::getInt64Ty(IdxTy->getContext());
- Constant *C1 = ConstantExpr::getSExtOrBitCast(Idx0, Int64Ty);
- Constant *C2 = ConstantExpr::getSExtOrBitCast(Combined, Int64Ty);
+ unsigned CommonExtendedWidth =
+ std::max(IdxTy->getIntegerBitWidth(),
+ Idx0->getType()->getIntegerBitWidth());
+ CommonExtendedWidth = std::max(CommonExtendedWidth, 64U);
+
+ Type *CommonTy =
+ Type::getIntNTy(IdxTy->getContext(), CommonExtendedWidth);
+ Constant *C1 = ConstantExpr::getSExtOrBitCast(Idx0, CommonTy);
+ Constant *C2 = ConstantExpr::getSExtOrBitCast(Combined, CommonTy);
Combined = ConstantExpr::get(Instruction::Add, C1, C2);
} else {
Combined =
NewIndices.push_back(Combined);
NewIndices.append(Idxs.begin() + 1, Idxs.end());
- return
- ConstantExpr::getGetElementPtr(CE->getOperand(0), NewIndices,
- inBounds &&
- cast<GEPOperator>(CE)->isInBounds());
+ return ConstantExpr::getGetElementPtr(
+ cast<GEPOperator>(CE)->getSourceElementType(), CE->getOperand(0),
+ NewIndices, inBounds && cast<GEPOperator>(CE)->isInBounds());
}
}
if (SrcArrayTy && DstArrayTy
&& SrcArrayTy->getElementType() == DstArrayTy->getElementType()
&& SrcPtrTy->getAddressSpace() == DstPtrTy->getAddressSpace())
- return ConstantExpr::getGetElementPtr((Constant*)CE->getOperand(0),
- Idxs, inBounds);
+ return ConstantExpr::getGetElementPtr(
+ SrcArrayTy, (Constant *)CE->getOperand(0), Idxs, inBounds);
}
}
}
// Check to see if any array indices are not within the corresponding
// notional array or vector bounds. If so, try to determine if they can be
// factored out into preceding dimensions.
- bool Unknown = false;
SmallVector<Constant *, 8> NewIdxs;
- Type *Ty = C->getType();
- Type *Prev = 0;
- for (unsigned i = 0, e = Idxs.size(); i != e;
+ Type *Ty = PointeeTy;
+ Type *Prev = C->getType();
+ bool Unknown = !isa<ConstantInt>(Idxs[0]);
+ for (unsigned i = 1, e = Idxs.size(); i != e;
Prev = Ty, Ty = cast<CompositeType>(Ty)->getTypeAtIndex(Idxs[i]), ++i) {
if (ConstantInt *CI = dyn_cast<ConstantInt>(Idxs[i])) {
if (isa<ArrayType>(Ty) || isa<VectorType>(Ty))
// dimension.
NewIdxs.resize(Idxs.size());
uint64_t NumElements = 0;
- if (
const ArrayType *ATy = dyn_cast<ArrayType>(Ty))
+ if (
auto *ATy = dyn_cast<ArrayType>(Ty))
NumElements = ATy->getNumElements();
else
NumElements = cast<VectorType>(Ty)->getNumElements();
Constant *PrevIdx = cast<Constant>(Idxs[i-1]);
Constant *Div = ConstantExpr::getSDiv(CI, Factor);
+ unsigned CommonExtendedWidth =
+ std::max(PrevIdx->getType()->getIntegerBitWidth(),
+ Div->getType()->getIntegerBitWidth());
+ CommonExtendedWidth = std::max(CommonExtendedWidth, 64U);
+
// Before adding, extend both operands to i64 to avoid
// overflow trouble.
- if (!PrevIdx->getType()->isIntegerTy(64))
- PrevIdx = ConstantExpr::getSExt(PrevIdx,
- Type::getInt64Ty(Div->getContext()));
- if (!Div->getType()->isIntegerTy(64))
- Div = ConstantExpr::getSExt(Div,
- Type::getInt64Ty(Div->getContext()));
+ if (!PrevIdx->getType()->isIntegerTy(CommonExtendedWidth))
+ PrevIdx = ConstantExpr::getSExt(
+ PrevIdx,
+ Type::getIntNTy(Div->getContext(), CommonExtendedWidth));
+ if (!Div->getType()->isIntegerTy(CommonExtendedWidth))
+ Div = ConstantExpr::getSExt(
+ Div, Type::getIntNTy(Div->getContext(), CommonExtendedWidth));
NewIdxs[i-1] = ConstantExpr::getAdd(PrevIdx, Div);
} else {
if (!NewIdxs.empty()) {
for (unsigned i = 0, e = Idxs.size(); i != e; ++i)
if (!NewIdxs[i]) NewIdxs[i] = cast<Constant>(Idxs[i]);
- return ConstantExpr::getGetElementPtr(C, NewIdxs, inBounds);
+ return ConstantExpr::getGetElementPtr(PointeeTy, C, NewIdxs, inBounds);
}
// 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))
- return ConstantExpr::getInBoundsGetElementPtr(C, Idxs);
+ if (!Unknown && !inBounds)
+ if (auto *GV = dyn_cast<GlobalVariable>(C))
+ if (!GV->hasExternalWeakLinkage() && isInBoundsIndices(Idxs))
+ return ConstantExpr::getInBoundsGetElementPtr(PointeeTy, C, Idxs);
- return 0;
+ return nullptr;
}
Constant *llvm::ConstantFoldGetElementPtr(Constant *C,
bool inBounds,
ArrayRef<Constant *> Idxs) {
- return ConstantFoldGetElementPtrImpl(C, inBounds, Idxs);
+ return ConstantFoldGetElementPtrImpl(
+ cast<PointerType>(C->getType()->getScalarType())->getElementType(), C,
+ inBounds, Idxs);
}
Constant *llvm::ConstantFoldGetElementPtr(Constant *C,
bool inBounds,
ArrayRef<Value *> Idxs) {
- return ConstantFoldGetElementPtrImpl(C, inBounds, Idxs);
+ return ConstantFoldGetElementPtrImpl(
+ cast<PointerType>(C->getType()->getScalarType())->getElementType(), C,
+ inBounds, Idxs);
+}
+
+Constant *llvm::ConstantFoldGetElementPtr(Type *Ty, Constant *C,
+ bool inBounds,
+ ArrayRef<Constant *> Idxs) {
+ return ConstantFoldGetElementPtrImpl(Ty, C, inBounds, Idxs);
+}
+
+Constant *llvm::ConstantFoldGetElementPtr(Type *Ty, Constant *C,
+ bool inBounds,
+ ArrayRef<Value *> Idxs) {
+ return ConstantFoldGetElementPtrImpl(Ty, C, inBounds, Idxs);
}
projects / oota-llvm.git / blobdiff