[PATCH] D103408: DetectDeadLanes: Remove assert for subregister defs

[Eli Friedman via Phabricator via llvm-commits]

efriedma added a comment.

I'm not sure this is the right fix.

>From my understanding, REG_SEQUENCE, INSERT_SUBREG, EXTRACT_SUBREG, and PHI should never target a subregister.  For COPY, we can target a subregister, but only if that register is a physical register.  So this patch only affects COPY instructions.

Given that, I think we should be bailing out sooner; trying to understand subregister defs of physical registers seems tricky, and not really related to the purpose of this pass.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D103408/new/

https://reviews.llvm.org/D103408