RFR(M) JDK-8181809 PPC64: Leverage mtfprd/mffprd on POWER8

[Matthew Brandyberry]

I think they are all guarded properly -- some at a higher level via 
predicate directives.  Which instance(s) in particular look unguarded?

On 6/20/17 8:58 AM, John Paul Adrian Glaubitz wrote:
> On Tue, Jun 20, 2017 at 08:46:25AM -0500, Matthew Brandyberry wrote:
>> These instructions were introduced with POWER8 and are not available in
>> earlier ISAs.
> Isn't your patch then missing some guarding such that these
> instructions aren't used when building on ppc64be with POWER5?
>
> We're still building openjdk-9 in Debian on ppc64 with POWER5 besides
> the ppc64el build with POWER8.
>
> Thanks,
> Adrian
>