[PATCH] D113679: [AMDGPU] Simplify 64-bit division/remainder expansion

[Jay Foad via Phabricator via llvm-commits]

foad created this revision.
Herald added subscribers: kerbowa, hiraditya, t-tye, tpr, dstuttard, yaxunl, nhaehnle, jvesely, kzhuravl, arsenm.
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The old expansion open-coded a 64-bit addition in a strange way, by
adding the high parts *without* carry-in from the low part, and then
adding the carry back in later on. Fixing this saves a couple of
instructions and makes the code much easier to understand.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D113679

Files:
  llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
  llvm/lib/Target/AMDGPU/AMDGPULegalizerInfo.cpp
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-sdiv.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-srem.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-udiv.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/legalize-urem.mir
  llvm/test/CodeGen/AMDGPU/GlobalISel/sdiv.i64.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/sdivrem.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/srem.i64.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/udiv.i64.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/udivrem.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/urem.i64.ll
  llvm/test/CodeGen/AMDGPU/amdgpu-codegenprepare-idiv.ll
  llvm/test/CodeGen/AMDGPU/bypass-div.ll
  llvm/test/CodeGen/AMDGPU/carryout-selection.ll
  llvm/test/CodeGen/AMDGPU/sdiv64.ll
  llvm/test/CodeGen/AMDGPU/srem64.ll
  llvm/test/CodeGen/AMDGPU/udiv64.ll
  llvm/test/CodeGen/AMDGPU/urem64.ll