[PATCH] D109858: [GlobalISel][AMDGPU] Add a -final-dce-legalizer flag to clean up dead code after legalization.

[Amara Emerson via Phabricator via llvm-commits]

aemerson created this revision.
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The legalizer doesn't always catch dead code, so when using the test update scripts for legalizer tests, some codegen changes might look worse due to different dead instructions being left behind. We probably don't want to enable this by default since dead code gets cleaned up anyway by later combines/isel.

Update some AMDGPU tests which motivated this change, as another patch will need this to get a better idea of how codegen actually changed.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D109858

Files:
  llvm/lib/CodeGen/GlobalISel/Legalizer.cpp
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-ashr.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-bitcast.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fcanonicalize.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fcos.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fdiv.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-ffloor.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fma.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fmaxnum.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fminnum.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fmul.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fshl.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fshr.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fsin.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fsqrt.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-fsub.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-insert-vector-elt.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-intrinsic-round.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-load-constant.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-load-flat.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-load-global.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-load-local.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-load-private.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-lshr.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-saddo.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-saddsat.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-select.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-sext-inreg.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-shl.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-smax.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-smin.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-sshlsat.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-ssubo.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-ssubsat.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-uaddo.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-uaddsat.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-umax.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-umin.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-ushlsat.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-usubo.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-usubsat.mir