[PATCH] D130746: RFC: Uniformity Analysis for Irreducible Control Flow

[Sameer Sahasrabuddhe via Phabricator via llvm-commits]

sameerds added a comment.

Bump!

This review has been waiting for attention for close to four months now. The uniformity analysis is important for the following:

1. Lay a strong groundwork for defining the convergence control intrinsics proposed in D85603 <https://reviews.llvm.org/D85603>. This is meant to completely replace the currently under-specified “convergent” attribute in LLVM IR.
2. Improve optimizations in irreducible CFGs.
3. Make uniformity analysis available in MIR, thus improving code generation. Especially the AMDGPU backend will greatly benefit from this information when allocating scalar/vector registers in a wave.

So far, there have been some comments that are “not opposed” to the change. It’s not clear if people who should be interested in the patch are able to provide the right attention. The work was presented at the LLVM Dev Meeting in San Jose too, in order to attract more attention.

I would really like some advice on how to move this forward. The concepts are sound, as far as they were reviewed by people working directly on that change. The analysis is new and does not affect existing pipelines. The AMDGPU pipeline is eager to use this analysis and is committed to maintaining it. Is this sufficient reason to let the patch through?

For submitting, at least a code review is necessary, which does not need domain expertise.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D130746/new/

https://reviews.llvm.org/D130746