[PATCH] D127188: [InstCombine] improve fold for icmp-ugt-ashr

[Sanjay Patel via Phabricator via llvm-commits]

spatel added a comment.

For reference, this was the Alive2 from the original review ( D117365 <https://reviews.llvm.org/D117365> ):
https://alive2.llvm.org/ce/z/tFAcZt

To catch the overflow case, I think we check if the incremented + shifted constant became signed min (0x8000...):
https://alive2.llvm.org/ce/z/RZdftJ

So that should be simpler than the pre-condition currently shown in this patch.

  (C + 1).shl(ShAmtVal).isMinSignedValue()


Repository:
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  https://reviews.llvm.org/D127188/new/

https://reviews.llvm.org/D127188