[all-commits] [llvm/llvm-project] 94230c: [AMDGPU] Fix lack of LDS DMA check in the AA handl...

[Stanislav Mekhanoshin via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 94230ce548c2f69db4cf9ef92ccb51d59030e7e3
      https://github.com/llvm/llvm-project/commit/94230ce548c2f69db4cf9ef92ccb51d59030e7e3
  Author: Stanislav Mekhanoshin <rampitec at users.noreply.github.com>
  Date:   2023-12-18 (Mon, 18 Dec 2023)

  Changed paths:
    M llvm/lib/Target/AMDGPU/SIInstrInfo.cpp

  Log Message:
  -----------
  [AMDGPU] Fix lack of LDS DMA check in the AA handling (#75249)

SIInstrInfo::areMemAccessesTriviallyDisjoint does a DS offset checks,
but does not account for LDS DMA instructions. Added these checks.
Without it code falls through and returns true which is wrong. As a
result mayAlias would always return false for LDS DMA and a regular LDS
instruction or 2 LDS DMA instructions.

At the moment this is NFCI because we do not use this AA in a context
which may touch LDS DMA instructions. This is also unreacheable now
because of the ordered memory ref checks just above in the function and
LDS DMA is marked as volatile. This volatile marking is removed in PR
#75247, therefore I'd submit this check before #75247.