diff options
Diffstat (limited to 'llvm/lib/Transforms')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp index 2b20d8e0357..5f21666f65a 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp @@ -470,7 +470,8 @@ Instruction *InstCombiner::FoldShiftByConstant(Value *Op0, Constant *Op1, // If the operand is a bitwise operator with a constant RHS, and the // shift is the only use, we can pull it out of the shift. - if (ConstantInt *Op0C = dyn_cast<ConstantInt>(Op0BO->getOperand(1))) { + const APInt *Op0C; + if (match(Op0BO->getOperand(1), m_APInt(Op0C))) { bool isValid = true; // Valid only for And, Or, Xor bool highBitSet = false; // Transform if high bit of constant set? @@ -495,10 +496,11 @@ Instruction *InstCombiner::FoldShiftByConstant(Value *Op0, Constant *Op1, // operation. // if (isValid && I.getOpcode() == Instruction::AShr) - isValid = Op0C->getValue()[TypeBits-1] == highBitSet; + isValid = Op0C->isNegative() == highBitSet; if (isValid) { - Constant *NewRHS = ConstantExpr::get(I.getOpcode(), Op0C, Op1); + Constant *NewRHS = ConstantExpr::get(I.getOpcode(), + cast<Constant>(Op0BO->getOperand(1)), Op1); Value *NewShift = Builder.CreateBinOp(I.getOpcode(), Op0BO->getOperand(0), Op1); |
