[PATCH] hppa: Optimize atomic_compare_and_exchange_val_acq

[Florian Weimer]

* John David Anglin:

>>> The change was intended as an optimization but tst-stack4 now passes.
>> 
>> This is a red flag for this patch.
>
> The patch has had a significant amount of testing and I'm sure there
> are no functional issues.  It is important to simplify
> when possible.
>
> Why red flag an improvement in test results?

I share Carlos' concern.  If this patch appears to fix tst-stack4,
then it has unforeseen consequences.  We just don't understand the
full impact of this change.