[PATCH] D107859: [AMDGPU] MachineLICM cannot hoist VALU

[Stanislav Mekhanoshin via Phabricator via llvm-commits]

rampitec created this revision.
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MachineLoop::isLoopInvariant() returns false for all VALU
because of the exec use. Check TII::isIgnorableUse() to
allow hoisting.

That unfortunately results in higher register consumption
since MachineLICM does not adequately estimate pressure.
Therefor I think it shall only be enabled after D107677 <https://reviews.llvm.org/D107677> even
though it does not depend on it.


https://reviews.llvm.org/D107859

Files:
  llvm/lib/CodeGen/MachineLoopInfo.cpp
  llvm/test/CodeGen/AMDGPU/dag-divergence-atomic.ll
  llvm/test/CodeGen/AMDGPU/fp64-atomics-gfx90a.ll
  llvm/test/CodeGen/AMDGPU/global-atomics-fp.ll
  llvm/test/CodeGen/AMDGPU/indirect-call.ll
  llvm/test/CodeGen/AMDGPU/infinite-loop.ll
  llvm/test/CodeGen/AMDGPU/mul24-pass-ordering.ll
  llvm/test/CodeGen/AMDGPU/sdiv64.ll
  llvm/test/CodeGen/AMDGPU/srem64.ll
  llvm/test/CodeGen/AMDGPU/udiv64.ll
  llvm/test/CodeGen/AMDGPU/unstructured-cfg-def-use-issue.ll
  llvm/test/CodeGen/AMDGPU/urem64.ll
  llvm/test/CodeGen/AMDGPU/vgpr-descriptor-waterfall-loop-idom-update.ll
  llvm/test/CodeGen/AMDGPU/wave32.ll

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