[PATCH] D142192: [AMDGPU] Run unmerge combines post regbankselect

[Pierre van Houtryve via Phabricator via llvm-commits]

Pierre-vh created this revision.
Pierre-vh added reviewers: foad, arsenm.
Herald added subscribers: kosarev, StephenFan, kerbowa, hiraditya, tpr, dstuttard, yaxunl, jvesely, kzhuravl.
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Pierre-vh requested review of this revision.
Herald added subscribers: llvm-commits, wdng.
Herald added a project: LLVM.

RegBankSelect can insert G_UNMERGE_VALUES in a lot of places which
left us with a lot of unmerge/merge pairs that could be simplified.
These often got in the way of pattern matching and made codegen
worse.

This patch:

- Makes the necessary changes to the merge/unmerge combines so they can run post RegBankSelect
- Adds relevant unmerge combines to the list of RegBankSelect combines for AMDGPU
- Updates some tablegen patterns that were missing explicit cross-regbank copies (V_BFI patterns were causing constant bus violations with this change).

This seems to be mostly beneficial for code quality.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D142192

Files:
  llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp
  llvm/lib/Target/AMDGPU/AMDGPUCombine.td
  llvm/lib/Target/AMDGPU/SIInstructions.td
  llvm/test/CodeGen/AMDGPU/GlobalISel/extractelement.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/fshl.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/fshr.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/image-waterfall-loop-O0.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/insertelement.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.buffer.atomic.add.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.buffer.atomic.cmpswap.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.buffer.atomic.fadd.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.buffer.load.format.f16.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.buffer.load.format.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.buffer.load.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.buffer.store.format.f16.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.buffer.store.format.f32.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.buffer.store.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.tbuffer.load.f16.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.tbuffer.load.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.tbuffer.store.f16.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.tbuffer.store.i8.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.raw.tbuffer.store.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.s.buffer.load.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.struct.buffer.atomic.add.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.struct.buffer.atomic.cmpswap.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.struct.buffer.atomic.fadd.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.struct.buffer.load.format.f16.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.struct.buffer.load.format.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.struct.buffer.load.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.struct.buffer.store.format.f16.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.struct.buffer.store.format.f32.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.struct.buffer.store.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.struct.tbuffer.load.f16.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.struct.tbuffer.load.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/saddsat.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/sext_inreg.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/srem.i64.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/ssubsat.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/urem.i64.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/xnor.ll
  llvm/test/CodeGen/AMDGPU/bfi_int.ll
  llvm/test/CodeGen/AMDGPU/constrained-shift.ll
  llvm/test/CodeGen/AMDGPU/cttz_zero_undef.ll