[PATCH] D134183: [WIP][RegCoalescer][TwoAddrInst] Keep undef subreg copies that are used in early-clobber insts

[Abinav Puthan Purayil via Phabricator via llvm-commits]

abinavpp created this revision.
abinavpp added reviewers: arsenm, foad, rampitec, yaxunl.
Herald added subscribers: kosarev, mstorsjo, kerbowa, dmgreen, tpr, hiraditya, jvesely, qcolombet, MatzeB.
Herald added a project: All.
abinavpp requested review of this revision.
Herald added subscribers: llvm-commits, wdng.
Herald added a project: LLVM.

In isel patterns targeting early clobber instructions, the src pattern
can have implicit_def subregs in a reg_sequence operand. We need to keep
the undef subreg copy so that regalloc doesn't assign overlapping
register.

Fixes a problem in SWDEV-352540


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D134183

Files:
  llvm/lib/CodeGen/RegisterCoalescer.cpp
  llvm/lib/CodeGen/TwoAddressInstructionPass.cpp
  llvm/test/CodeGen/AMDGPU/atomic_optimizations_buffer.ll
  llvm/test/CodeGen/AMDGPU/atomic_optimizations_global_pointer.ll
  llvm/test/CodeGen/AMDGPU/atomic_optimizations_local_pointer.ll
  llvm/test/CodeGen/AMDGPU/atomic_optimizations_raw_buffer.ll
  llvm/test/CodeGen/AMDGPU/atomic_optimizations_struct_buffer.ll
  llvm/test/CodeGen/AMDGPU/mad_64_32.ll
  llvm/test/CodeGen/AMDGPU/mad_u64_u32.ll
  llvm/test/CodeGen/Thumb2/mve-laneinterleaving-cost.ll
  llvm/test/CodeGen/Thumb2/mve-satmul-loops.ll
  llvm/test/CodeGen/Thumb2/mve-vmull-splat.ll

-------------- next part --------------
A non-text attachment was scrubbed...
Name: D134183.461203.patch
Type: text/x-patch
Size: 36138 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20220919/13f690fd/attachment.bin>