[PATCH] D108651: [SCEV] Use no-self-wrap flags infered from exit structure to compute trip count

[Philip Reames via Phabricator via llvm-commits]

reames created this revision.
reames added reviewers: nikic, efriedma, lebedev.ri.
Herald added subscribers: javed.absar, bollu, hiraditya, mcrosier.
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Herald added a project: LLVM.

This isn't quite ready to land yet.   It needs some tests added and rebased, but I wanted to post it to get feedback on the direction.  The major alternative here would be to return a conservative upper bound, and then rely on two invocations of indvars to add the facts to the narrow IV, and then reconstruct SCEV.  (I have not implemented the alternative and am not 100% sure this would work out.)  That's arguably more in line with existing code, but I find this substantially easier to reason about.  Thoughts?


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D108651

Files:
  llvm/lib/Analysis/ScalarEvolution.cpp

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