[PATCH] D120544: [AMDGPU] Omit unnecessary waitcnt before barriers

[Austin Kerbow via Phabricator via llvm-commits]

kerbowa added a comment.
Herald added a subscriber: kosarev.

JFYI, I'm planning to reintroduce this change in the next few weeks. Before this change, the compiler would ALWAYS wait for outstanding VMEM/LGKM at barriers. There is no HW requirement for this. As an optimization, we will be omitting these waitcnt on Navi/MI200. In order to retain the same behavior as before the change, fences must be added before barriers.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D120544/new/

https://reviews.llvm.org/D120544