[PATCH] D54184: RegisterCoalescer: Don't skip resolveConflicts for SubRegJoin

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added a comment.

However, this variant still fails:

body:             |

  bb.0:
    successors: %bb.1
    undef %0.sub1:sreg_64_xexec = IMPLICIT_DEF
  
  bb.1:
    %0.sub0:sreg_64_xexec = S_MOV_B32 0
    %1:sreg_64 = COPY %0:sreg_64_xexec
    dead %0.sub1:sreg_64_xexec = COPY %0.sub0:sreg_64_xexec
    S_ENDPGM implicit %1.sub1:sreg_64


https://reviews.llvm.org/D54184