hanbeom 4ef22fce82 [InstCombine] Simplify select if it combinated and/or/xor (#73362) ...

`and/or/xor` operations can each be changed to sum of logical
operations including operators other than themselves.

 `x&y -> (x|y) ^ (x^y)`
 `x|y -> (x&y) | (x^y)`
 `x^y -> (x|y) ^ (x&y)`

if left of condition of `SelectInst` is `and/or/xor` logical
operation and right is equal to `0, -1`, or a `constant`, and
if `TrueVal` consist of `and/or/xor` logical operation then we
can optimize this case.

This patch implements this combination.

Proof: https://alive2.llvm.org/ce/z/WW8iRR

Fixes https://github.com/llvm/llvm-project/issues/71792.

2024-04-03 14:29:10 +08:00

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