[PATCH] D40556: SIFixSGPRCopies should not change non-divergent PHI

[Samuel Pitoiset via Phabricator via llvm-commits]

hakzsam added a comment.

In https://reviews.llvm.org/D40556#1062962, @alex-t wrote:

> In fact yes. This is the most correct solution. The stuff in
>  SIFixSGPRCopies.cpp has got to gone.
>  So it does not make sense to spend efforts on it. Moreover there is no
>  correct solution at all
>  unless we implement one more DivergenceAnalysis upon the machine IR.
>  So, if it's okay I'd prefer to revert.


I'm fine with the revert because this change introduces hangs in a bunch of games apparently.

Do you think it's doable to backport the revert to LLVM 6 as well?

Thanks!


Repository:
  rL LLVM

https://reviews.llvm.org/D40556