[PATCH] D63405: GlobalISel: Don't lose fneg flags when lowering to fsub

[Sanjay Patel via Phabricator via llvm-commits]

spatel accepted this revision.
spatel added a comment.

This matches my mental model for FMF propagation, so LGTM.

But there's a separate question that is raised here: why is it legal to convert fneg to fsub -0.0? That loosens the IEEE requirement when dealing with a NAN. I'd think this should be legalized by converting to integer and flipping the sign bit (xor).
ping @cameron.mcinally


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D63405/new/

https://reviews.llvm.org/D63405