[PATCH] D94014: [InstCombine] reduce icmp(ashr X, C1), C2 to sign-bit test

[Sanjay Patel via Phabricator via llvm-commits]

spatel updated this revision to Diff 315782.
spatel added a comment.

Ping.
Note: I added a bitwidth > 2 constraint to be safe and avoid degenerate narrow bit patterns, but I'm not sure how to write negative tests for that would actually survive to this point in instcombine (instsimplify appears to reduce those first).


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D94014/new/

https://reviews.llvm.org/D94014

Files:
  llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
  llvm/test/Transforms/InstCombine/icmp-shr.ll

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