[PATCH] InstCombine ((x | ~y) ^ (~x ^ y)) to (x & ~y)

[Anton Korobeynikov]

> There is a discussion is going on at http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075532.html regarding a more general way to handle matching
> different patterns. If we can come up with a general approach that would be best. But till then we should not miss any optimizing opportunity I think.
Sure. Just present how often this pattern triggers on LLVM testsuite and SPEC.

-- 
With best regards, Anton Korobeynikov
Faculty of Mathematics and Mechanics, Saint Petersburg State University