[all-commits] [llvm/llvm-project] 764676: [fastregalloc] Fix bug when undef value is tied to...

[Luo, Yuanke via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 764676b737db0f259ef018104edbc2aec9db7e7d
      https://github.com/llvm/llvm-project/commit/764676b737db0f259ef018104edbc2aec9db7e7d
  Author: Luo, Yuanke <yuanke.luo at intel.com>
  Date:   2022-05-04 (Wed, 04 May 2022)

  Changed paths:
    M llvm/lib/CodeGen/RegAllocFast.cpp
    A llvm/test/CodeGen/X86/fastregalloc-tied-undef.mir

  Log Message:
  -----------
  [fastregalloc] Fix bug when undef value is tied to def.

If the tied use is undef value, fastregalloc should free the def
register. There is no reload needed for the undef value.

Reviewed By: MatzeB

Differential Revision: https://reviews.llvm.org/D124834