[PATCH] D148591: [InstCombine] Improve eq/ne by parts to handle `ult/ugt` equality pattern.

[Noah Goldstein via Phabricator via llvm-commits]

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`(icmp eq/ne (lshr x, C), (lshr y, C)` gets optimized to `(icmp
ult/uge (xor x, y), (1 << C)`. This can cause the current equal by
parts detection to miss the high-bits as it may get optimized to the
new pattern.

This commit adds support for detecting / combining the `ult/ugt`
pattern.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D148591

Files:
  llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
  llvm/test/Transforms/InstCombine/eq-of-parts.ll

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