diff options
Diffstat (limited to 'llvm/lib/Analysis/ValueTracking.cpp')
-rw-r--r-- | llvm/lib/Analysis/ValueTracking.cpp | 27 |
1 files changed, 14 insertions, 13 deletions
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp index 9972a43..a5259ba7 100644 --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -6035,28 +6035,29 @@ bool llvm::isSafeToSpeculativelyExecuteWithOpcode( case Instruction::UDiv: case Instruction::URem: { // x / y is undefined if y == 0. - const DataLayout &DL = Inst->getModule()->getDataLayout(); - return isKnownNonZero(Inst->getOperand(1), DL, /*Depth*/ 0, AC, CtxI, DT); + const APInt *V; + if (match(Inst->getOperand(1), m_APInt(V))) + return *V != 0; + return false; } case Instruction::SDiv: case Instruction::SRem: { // x / y is undefined if y == 0 or x == INT_MIN and y == -1 - const DataLayout &DL = Inst->getModule()->getDataLayout(); - KnownBits KnownDenominator = - computeKnownBits(Inst->getOperand(1), DL, /*Depth*/ 0, AC, CtxI, DT); + const APInt *Numerator, *Denominator; + if (!match(Inst->getOperand(1), m_APInt(Denominator))) + return false; // We cannot hoist this division if the denominator is 0. - if (!KnownDenominator.isNonZero()) + if (*Denominator == 0) return false; - // It's safe to hoist if the denominator is not 0 or -1. - if (!KnownDenominator.Zero.isZero()) + if (!Denominator->isAllOnes()) return true; - - // At this point denominator may be -1. It is safe to hoist as + // At this point we know that the denominator is -1. It is safe to hoist as // long we know that the numerator is not INT_MIN. - KnownBits KnownNumerator = - computeKnownBits(Inst->getOperand(0), DL, /*Depth*/ 0, AC, CtxI, DT); - return !KnownNumerator.getSignedMinValue().isMinSignedValue(); + if (match(Inst->getOperand(0), m_APInt(Numerator))) + return !Numerator->isMinSignedValue(); + // The numerator *might* be MinSignedValue. + return false; } case Instruction::Load: { const LoadInst *LI = dyn_cast<LoadInst>(Inst); |