[all-commits] [llvm/llvm-project] e12957: [Uniformity] Legacy PM: Set UniformityInfoWrapperP...

[Jim M. R. Teichgräber via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: e12957080ce145fa137ed6a1b16b660719a9cbb5
      https://github.com/llvm/llvm-project/commit/e12957080ce145fa137ed6a1b16b660719a9cbb5
  Author: Jim M. R. Teichgräber <Jim.Teichgraber at amd.com>
  Date:   2025-07-11 (Fri, 11 Jul 2025)

  Changed paths:
    M llvm/lib/Analysis/UniformityAnalysis.cpp

  Log Message:
  -----------
  [Uniformity] Legacy PM: Set UniformityInfoWrapperPass isCFGOnly to false (#148165)

Currently, Uniformity Analysis is preserved in the Legacy PM when a pass
sets `setPreservesCFG()`. This is incorrect: any values' uniformity not
only depends on the CFG, but also on the uniformity of other values, so
a CFG-preserving change in many cases doesn't preserve uniformity
analysis.

This corrected behavior also matches the behavior of the new PM.

---

On its own, this change does not affect the pass pipeline because of the
happenstance of pass ordering. I also created a PR to change
AMDGPULateCodeGenPrepare (#148167), this will have an actual impact on
pass executions. That PR also includes changes to the
`amdgpu/llc-pipeline.ll` test in order to check that this change works,
but if this is preferred, I would also be happy to try to extend this PR
to add an isolated test case; though my personal opinion is that the
test in #148167 should suffice, as it should also accurately pinpoint
failures related to this change.

---

I ran `git-clang-format` on my changes. I tested them using the
`check-llvm` target; no unexpected failures occurred.



To unsubscribe from these emails, change your notification settings at https://github.com/llvm/llvm-project/settings/notifications