[libc-commits] [PATCH] D159276: [libc][gpu] Thread divergence fix on volta, WIP

[Joseph Huber via Phabricator via libc-commits]

jhuber6 added a comment.

We have a single test that opens and closes in a divergent state, it was the original one that caught deadlocks on AMDGPU https://github.com/llvm/llvm-project/blob/main/libc/test/integration/startup/gpu/rpc_test.cpp. This is definitely a good idea on AMDGPU, when I originally tested it we end up exchanging about 7  VGPRs for about 6 SGPRs which is a very good trade-off. I think the best we can do is just maintain the divergence that we know of when we open the RPC interface. That is, when we broadcast the value we should write it to the mask we know of, since that's always a subset of the "true mask" right?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D159276/new/

https://reviews.llvm.org/D159276