[all-commits] [llvm/llvm-project] 8dfb41: [AMDGPU] Fix missing waitcnt issue

[Piotr Sobczak via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 8dfb417e67e33055a72980ede92c128763d549ad
      https://github.com/llvm/llvm-project/commit/8dfb417e67e33055a72980ede92c128763d549ad
  Author: Piotr Sobczak <Piotr.Sobczak at amd.com>
  Date:   2022-01-19 (Wed, 19 Jan 2022)

  Changed paths:
    M llvm/lib/Target/AMDGPU/SIInsertWaitcnts.cpp
    M llvm/test/CodeGen/AMDGPU/waitcnt.mir

  Log Message:
  -----------
  [AMDGPU] Fix missing waitcnt issue

Ignore out of order counters when merging brackets. The fact that
there was a pending event in the old state does not guarantee that
the waitcnt was generated, so we still need to conservatively re-process
the block.

The patch fixes a correctness issue where the block was not re-processed
and the waitcnt not inserted in consequence.

Differential Revision: https://reviews.llvm.org/D117544