diff options
Diffstat (limited to 'llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp index 15e0889b51b..e210c99d126 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp @@ -1273,6 +1273,10 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { if (Value *V = FoldLogicalPlusAnd(Op0LHS, Op0RHS, AndRHS, true, I)) return BinaryOperator::CreateAnd(V, AndRHS); + // -x & 1 -> x & 1 + if (AndRHSMask == 1 && match(Op0LHS, m_Zero())) + return BinaryOperator::CreateAnd(Op0RHS, AndRHS); + // (A - N) & AndRHS -> -N & AndRHS iff A&AndRHS==0 and AndRHS // has 1's for all bits that the subtraction with A might affect. if (Op0I->hasOneUse() && !match(Op0LHS, m_Zero())) { |
