[PATCH] D39642: [ValueTracking] readnone is a requirement for converting sqrt to llvm.sqrt; nnan is not

[Eli Friedman via Phabricator via llvm-commits]

efriedma accepted this revision.
efriedma added a subscriber: arsenm.
efriedma added a comment.
This revision is now accepted and ready to land.

LGTM.

> But after reviewing the C standard text, I'm not sure the previous behavior was correct in the first place. If "implementation-defined" is actually defined by the platform, then a compiler can't assume that value (is nan) as we were doing?

I'm not sure how the C standard fits into this?  "-ffinite-math-only" mode intentionally doesn't conform to the C standard.


https://reviews.llvm.org/D39642