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[InstCombine] Make the (A|B)^B -> A & ~B transform code consistent with the very similar (A&B)^B -> ~A & B code. This should be NFC except for the addition of hasOneUse check. 

I think this code is still overly complicated and should use matchers, but first I wanted to make it consistent.

llvm-svn: 299834
This commit is contained in:
Craig Topper 2017-04-10 06:53:21 +00:00
parent 4f16d82d6b
commit 4738321f0c
1 changed files with 5 additions and 5 deletions
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10
llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
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@ -2504,12 +2504,12 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) {
BinaryOperator *Op1I = dyn_cast<BinaryOperator>(Op1);
if (Op1I) {
Value *A, *B;
if (match(Op1I, m_Or(m_Value(A), m_Value(B)))) {
if (A == Op0) { // B^(B|A) == (A|B)^B
if (match(Op1I, m_OneUse(m_Or(m_Value(A), m_Value(B))))) {
if (A == Op0) { // A^(A|B) == A^(B|A)
Op1I->swapOperands();
I.swapOperands();
std::swap(Op0, Op1);
} else if (B == Op0) { // B^(A|B) == (A|B)^B
std::swap(A, B);
}
if (B == Op0) { // A^(B|A) == (B|A)^A
I.swapOperands(); // Simplified below.
std::swap(Op0, Op1);
}