[Bug rtl-optimization/68664] [6/7 Regression] Speculative sqrt in c-ray main loop causes large slow down

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68664

--- Comment #22 from Segher Boessenkool <segher at gcc dot gnu.org> ---
(In reply to Jan Hubicka from comment #20)
> There was also regression on cray for x86-64
> https://gcc.opensuse.org/c++bench-czerny/c-ray/
> Is it the same issue?

I don't think so.  But I don't know much about that bug, it is something
with AVX I think?  If you are talking about PR79224.

> Also with profile feedback perhaps you have enough info to tell that the
> speculative path is almost as likely as the original placement.

Maybe.  The gain will be tiny though, afaics.

> I wonder if we can provie resonable default by RTX cost...

Not for rs6000 at least.