[PATCH] D51257: [RegisterCoalescer] Do not eliminateUndefCopy for a partial copy

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


================
Comment at: lib/CodeGen/RegisterCoalescer.cpp:1500-1502
+  if (DstSubIdx)
+    return nullptr;
+
----------------
I would also expect this to be OK if DstSubIdx == SrcSubIdx?


Repository:
  rL LLVM

https://reviews.llvm.org/D51257