[PATCH, rs6000] Fix PR target/70168

[David Edelsohn]

On Thu, Mar 10, 2016 at 6:10 PM, Ulrich Weigand <uweigand@de.ibm.com> wrote:
> Hello,
>
> this patch fixes PR target/70168, a wrong code generation problem
> caused by rs6000_expand_atomic_compare_and_swap not properly handling
> the case where changing retval clobbers newval due to a register overlap.
>
> Tested with no regressions on powerpc64le-linux on mainline
> and gcc-5-branch.
>
> OK for both?
>
> Bye,
> Ulrich
>
>
> ChangeLog:
>
>         PR target/70168
>         * config/rs6000/rs6000.c (rs6000_expand_atomic_compare_and_swap):
>         Handle overlapping retval and newval.

Okay everywhere.

Thanks, David