libstdc++: Minor codegen improvement for atomic wait spinloop

[Thomas Rodgers]

Ok for trunk? backport?

On Wed, Jul 6, 2022 at 1:56 PM Jonathan Wakely <jwakely@redhat.com> wrote:

> On Wed, 6 Jul 2022 at 02:05, Thomas Rodgers via Libstdc++
> <libstdc++@gcc.gnu.org> wrote:
> >
> > This patch merges the spin loops in the atomic wait implementation which
> is
> > a
> > minor codegen improvement.
> >
> > libstdc++-v3/ChangeLog:
> >          * include/bits/atomic_wait.h (__atomic_spin): Merge spin loops.
>
> OK, thanks.
>
>