[PATCH] D108642: [CGProfile] allows undef in metadata node storing function pointers

[Duncan P. N. Exon Smith via Phabricator via llvm-commits]

dexonsmith added a comment.

It used to be that when GlobalValue-derived Constants were removed, then metadata would point at `null` instead. Not sure if that changed at some point, or if this is a unique code path, but it's not clear whether having two possible "no value" values (undef vs. null) is a good idea.

Can you explain why https://reviews.llvm.org/rGe5d958c45629ccd2f5b5f7432756be1d0fcf052c used `undef` instead of `null`? Should it use `null` instead?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D108642/new/

https://reviews.llvm.org/D108642