[PATCH] D146596: [SCEV] Infer no-self-wrap via constant ranges

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/lib/Analysis/ScalarEvolution.cpp:4995
+      ConstantRange StepCR = getSignedRange(AR->getStepRecurrence(*this));
+      ConstantRange BECountCR = getUnsignedRange(BECount);
+      unsigned NoOverflowBitWidth =
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I think it would make more sense to use the constant max BECount here, rather than the range of the exact BECount. That should be strictly more powerful and is also more in line with how we infer nuw/nsw on affine addrecs.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D146596/new/

https://reviews.llvm.org/D146596