RFR(S) JDK-8181810 PPC64: Leverage extrdi for bitfield extract

[Doerr, Martin]

Hi Matt,

nice change. I have reviewed it and didn't see any mistakes. We will build and test it, too.
I can also sponsor it after a 2nd review.

Thanks and best regards,
Martin


-----Original Message-----
From: hotspot-dev [mailto:hotspot-dev-bounces at openjdk.java.net] On Behalf Of Matthew Brandyberry
Sent: Montag, 19. Juni 2017 18:35
To: hotspot-dev at openjdk.java.net
Subject: Re: RFR(S) JDK-8181810 PPC64: Leverage extrdi for bitfield extract

Apologies for the bad cut-and-paste job.. the body of this review 
request should
read as follows:

This is a PPC-specific hotspot optimization that leverages the extrdi 
instruction
for bitfield extract operations (shift-right and mask-with-and). It 
yields a
~25% improvement measured via a microbenchmark.

Please review:

Bug: https://bugs.openjdk.java.net/browse/JDK-8181810
Webrev: http://cr.openjdk.java.net/~gromero/8181810/v1/

Thanks,
Matt


On 6/19/17 11:30 AM, Matthew Brandyberry wrote:
> This is a PPC-specific hotspot optimization that leverages the 
> mtfprd/mffprd
> instructions for for movement between general purpose and floating point
> registers (rather than through memory).  It yields a ~35% improvement 
> measured
> via a microbenchmark.
>
> Please review:
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8181809
> Webrev: http://cr.openjdk.java.net/~gromero/8181809/v1/
>
> Thanks,
> Matt
>