[PATCH] D121381: [MemorySSA] Support lazy use optimization

[Philip Reames via Phabricator via llvm-commits]

reames added a comment.

I noticed by accident that MemCpyOpt does not call ensureOptimizedUses, and thus changes behavior after this change.  Not sure if that's good or bad, but it doesn't seem to have been explicitly noted in the review.  For call slot optimization, we do perform a lot of clobber walks from loads.

(Separately, we could recognize the code to perform far fewer clobber walks. - e.g. there's no point in searching for the clobber for any non-alloca location.)


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D121381/new/

https://reviews.llvm.org/D121381