[8u-dev] Request for backport approval: 8145913: PPC64: add Montgomery multiply intrinsic

[Doerr, Martin]

Hi Rob,

I have reviewed it as the author of the original change, but not as official backport reviewer (I'm only jdk9+10 reviewer).

Adding the int to long conversion is needed in 8u and looks correct to me.
It makes sense to leave the ad file alone. The jdk9 change contains some additional stuff in it which should not be part of the backport.

Best regards,
Martin


-----Original Message-----
From: Rob McKenna [mailto:rob.mckenna at oracle.com] 
Sent: Mittwoch, 27. September 2017 17:23
To: Gustavo Serra Scalet <gustavo.scalet at eldorado.org.br>
Cc: jdk8u-dev at openjdk.java.net; Doerr, Martin <martin.doerr at sap.com>
Subject: Re: [8u-dev] Request for backport approval: 8145913: PPC64: add Montgomery multiply intrinsic

Hi Gustavo,

Since the code has changed this requires a codereview for the 8 specific
code. (ideally from someone with ppc knowledge)

Approved subject to obtaining this review.

    -Rob

On 27/09/17 02:55, Gustavo Serra Scalet wrote:
> Hi,
> 
> 
> Original Bug: https://bugs.openjdk.java.net/browse/JDK-8145913
> Jdk9 change: http://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/ce0dacc26f3d
> Jdk9 review thread: http://mail.openjdk.java.net/pipermail/hotspot-compiler-dev/2015-December/020534.html
> 
> Unfortunately the Jdk9 change doesn't apply cleanly. Below the are reasons for the adaptations:
> 
> 1) This stub call uses integer type on a 64 bits register so a conversion to long was additionally needed.
> 2) Avoid changing the ppc.ad file as some interfaces were not existing.
> 
> My changes are available on: https://gut.github.io/openjdk/webrev/JDK-8145913/webrev/index.html
> 
> This change also belongs to 8u102 backport of https://bugs.openjdk.java.net/browse/JDK-8150152
> 
> 
> Thanks to this change, SpecJVM2008's crypto.rsa benchmark had a speedup of 3.1 on ppc64le!
> 
> Gustavo Serra Scalet
>