[all-commits] [llvm/llvm-project] 300a55: RegisterCoalescer: Fix implicit operand handling d...

[Matt Arsenault via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 300a55003c7ef7b3a87844a88781e4fdcba860ff
      https://github.com/llvm/llvm-project/commit/300a55003c7ef7b3a87844a88781e4fdcba860ff
  Author: Matt Arsenault <Matthew.Arsenault at amd.com>
  Date:   2023-12-13 (Wed, 13 Dec 2023)

  Changed paths:
    M llvm/lib/CodeGen/RegisterCoalescer.cpp
    A llvm/test/CodeGen/X86/coalescer-dead-flag-verifier-error.ll
    A llvm/test/CodeGen/X86/coalescer-remat-with-undef-implicit-def-operand.mir

  Log Message:
  -----------
  RegisterCoalescer: Fix implicit operand handling during rematerialize (#75271)

If the rematerialize was placing a subregister into a super register,
and implicit operands referenced the original register, we need to add
undef flags to the now-subregister indexed implicit operands.

Depends #75152