[InstCombine] try to canonicalize xor-of-icmps to and-of-icmps
We have a large portfolio of folds for and-of-icmps and or-of-icmps in InstSimplify and InstCombine,
but hardly anything for xor-of-icmps. Rather than trying to rethink and translate all of those folds,
we can use the truth table definition of xor:
X ^ Y --> (X | Y) & !(X & Y)
...to see if we can convert the xor to and/or and then use the existing folds.
http://rise4fun.com/Alive/J9v
Differential Revision: https://reviews.llvm.org/D33342
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305792 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed