[PATCH] D144606: [InstCombine] Add transforms for `(max/min (xor X, Pow2), X)` -> `(and/or X, Pow2/~Pow2)`

[Sanjay Patel via Phabricator via llvm-commits]

spatel added inline comments.


================
Comment at: llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp:1498-1500
+          // Negative power of 2 must be IntMin. Its possible to be able to
+          // prove negative / power of 2 without actually having known bits, so
+          // just get the value by hand.
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If we can prove that some value is a constant, then shouldn't we have zapped it already?
The test example shows that we are missing a fold like this:
https://alive2.llvm.org/ce/z/z5xok2


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https://reviews.llvm.org/D144606