diff options
Diffstat (limited to 'llvm/lib/Transforms')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp index fbd0165cd2d..9d640e849dc 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp @@ -1742,6 +1742,15 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) { return BinaryOperator::CreateAnd(A, B); } + // (sub (xor A, B) (or A, B)) --> neg (and A, B) + { + Value *A, *B; + if (match(Op0, m_Xor(m_Value(A), m_Value(B))) && + match(Op1, m_c_Or(m_Specific(A), m_Specific(B))) && + (Op0->hasOneUse() || Op1->hasOneUse())) + return BinaryOperator::CreateNeg(Builder.CreateAnd(A, B)); + } + { Value *Y; // ((X | Y) - X) --> (~X & Y) |
