diff options
| -rw-r--r-- | lib/Transforms/Scalar/InstructionCombining.cpp | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index 6db0717a9f..767fc9582b 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -746,6 +746,14 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) { return BinaryOperator::createAnd(Op0, NewNot); } + // -(X sdiv C) -> (X sdiv -C) + if (Op1I->getOpcode() == Instruction::Div) + if (ConstantSInt *CSI = dyn_cast<ConstantSInt>(Op0)) + if (CSI->getValue() == 0) + if (Constant *DivRHS = dyn_cast<Constant>(Op1I->getOperand(1))) + return BinaryOperator::createDiv(Op1I->getOperand(0), + ConstantExpr::getNeg(DivRHS)); + // X - X*C --> X * (1-C) if (dyn_castFoldableMul(Op1I) == Op0) { Constant *CP1 = |