[PATCH] D108910: [IndVars] Break backedge and replace PHIs if loop exits on 1st iteration

[Philip Reames via Phabricator via llvm-commits]

reames added a comment.

I have reverted this patch for a couple of reasons:

1. The commit message was incorrect.  The change did not actually break the backedge.
2. There doesn't seem to have been any discussion in the review of why folding the exits to taken in provably dead code was the correct answer.  In particular, why not fold to poison?  Or just leave it to loop deletion?  Motivation is important.

These comments should be easy to address.  I reverted mostly because of the functional issue in the split off patch, and decided to revert both to be safe.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D108910/new/

https://reviews.llvm.org/D108910