Revert r137781; I agree with Duncan's comment that the situation in question is clearly impossible given the current structure of the code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137853 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp
index 89e55a4..cfff9c0 100644
--- a/lib/Analysis/InstructionSimplify.cpp
+++ b/lib/Analysis/InstructionSimplify.cpp
@@ -1348,11 +1348,6 @@
std::swap(Op0, Op1);
}
- // A ^ A = 0
- // Do this first so that we catch the undef ^ undef "idiom".
- if (Op0 == Op1)
- return Constant::getNullValue(Op0->getType());
-
// A ^ undef -> undef
if (match(Op1, m_Undef()))
return Op1;
@@ -1361,6 +1356,10 @@
if (match(Op1, m_Zero()))
return Op0;
+ // A ^ A = 0
+ if (Op0 == Op1)
+ return Constant::getNullValue(Op0->getType());
+
// A ^ ~A = ~A ^ A = -1
if (match(Op0, m_Not(m_Specific(Op1))) ||
match(Op1, m_Not(m_Specific(Op0))))