[PATCH] D15718: Recognize patterns for ctpop and ctlz in instcombine

[Krzysztof Parzyszek via llvm-commits]

kparzysz created this revision.
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kparzysz set the repository for this revision to rL LLVM.

Recognize the patterns for population count and for count-leading-zeros in the instruction combiner and replace them with calls to the corresponding intrinsics.
The patterns are based on those in "Hacker's Delight".

Repository:
  rL LLVM

http://reviews.llvm.org/D15718

Files:
  lib/Transforms/InstCombine/InstCombineAddSub.cpp
  test/Transforms/InstCombine/ctlz-match.ll
  test/Transforms/InstCombine/ctpop-match.ll

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