[PATCH] D56355: [InstCombine] Simplify cttz/ctlz + icmp ugt/ult into mask check

[Nikita Popov via Phabricator via llvm-commits]

nikic created this revision.
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Followup to D55745 <https://reviews.llvm.org/D55745>, this time handling comparisons with ugt and ult predicates (which are the canonical forms for non-equality predicates).

Based on the results, for ctlz we have the nice property that the mask check can always be represented as a ult/ugt comparison instead. I'm wondering if I should just emit it directly in that form and drop the single use check?


Repository:
  rL LLVM

https://reviews.llvm.org/D56355

Files:
  lib/Transforms/InstCombine/InstCombineCompares.cpp
  test/Transforms/InstCombine/cmp-intrinsic.ll

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