[PATCH] D94860: [InstCombine] Optimize select (X == C), (icmp X Y), false

[Juneyoung Lee via Phabricator via llvm-commits]

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This patch adds transformation `select (X == C), (icmp X Y), false` ->
`select (X == C), (icmp C Y), false`.

After the select i1 -> and/or transformation is removed, this optimization
should be explicitly added as a select transformation.
This pattern seems quite common in Transforms/InstCombine.

Alive2 proof:
And: https://alive2.llvm.org/ce/z/dVoKnd
Or: https://alive2.llvm.org/ce/z/3hb9qS


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D94860

Files:
  llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
  llvm/lib/Transforms/InstCombine/InstCombineInternal.h
  llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
  llvm/test/Transforms/InstCombine/select-safe-transforms.ll

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