diff options
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp b/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp index d7bd80261ab..4e5bf7859db 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp @@ -1139,16 +1139,17 @@ Instruction *InstCombiner::visitSDiv(BinaryOperator &I) { if (Instruction *Common = commonIDivTransforms(I)) return Common; - // sdiv X, -1 == -X - if (match(Op1, m_AllOnes())) - return BinaryOperator::CreateNeg(Op0); - - // sdiv exact X, C --> ashr exact X, log2(C) const APInt *Op1C; - if (match(Op1, m_APInt(Op1C)) && I.isExact() && Op1C->isNonNegative() && - Op1C->isPowerOf2()) { - Value *ShAmt = ConstantInt::get(Op1->getType(), Op1C->exactLogBase2()); - return BinaryOperator::CreateExactAShr(Op0, ShAmt, I.getName()); + if (match(Op1, m_APInt(Op1C))) { + // sdiv X, -1 == -X + if (Op1C->isAllOnesValue()) + return BinaryOperator::CreateNeg(Op0); + + // sdiv exact X, C --> ashr exact X, log2(C) + if (I.isExact() && Op1C->isNonNegative() && Op1C->isPowerOf2()) { + Value *ShAmt = ConstantInt::get(Op1->getType(), Op1C->exactLogBase2()); + return BinaryOperator::CreateExactAShr(Op0, ShAmt, I.getName()); + } } if (Constant *RHS = dyn_cast<Constant>(Op1)) { |
