[PATCH] D117252: [InstCombine] Fold ashr-exact into a icmp-ugt.

[Craig Topper via Phabricator via llvm-commits]

craig.topper added a comment.

In D117252#3242535 <https://reviews.llvm.org/D117252#3242535>, @nadav wrote:

> @craig.topper thank you for the review. I removed the two predicated that are canonicalized before this method is called (ICMP_SGE and ICMP_UGE). I also used the script update_test_checks.py to update the check lines. I also verified with alive2 that the transformation is correct for ICMP_UGT, but only when the exact flag is present  (link:  https://alive2.llvm.org/ce/z/qBhxAM).

Thanks Nadav. My UGT question was directed at the transform immediately below. Where it’s looking for SGT and a constant that is 1 less. That would be the form that UGE would canonicalize to I think. Something like this https://alive2.llvm.org/ce/z/6EXVFs


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https://reviews.llvm.org/D117252