RFR: JDK-8141634 Implement VarHandles/Unsafe intrinsics on SPARC

[David Holmes]

Hi Trevor,

On 26/08/2016 6:00 PM, Trevor Watson wrote:
> Hi David,
>
> Thanks for that information. I already suspected that 32-bit was no
> longer supported, but as I'm new to working on this code I didn't want
> to go changing to many things at once.
>
> Would you be okay if I logged a separate bug to remove the 32-bit checks
> and supports_cx8 predicate? That was I can focus on just those things.

I was only suggesting not including them in this new code. Removing them 
from existing code is a different matter.

Thanks,
David

> Trevor
>
> On 26/08/16 04:44, David Holmes wrote:
>> Hi Trevor,
>>
>> Not a full review as I'm not familiar with .ad file syntax and
>> structure. Two observations:
>>
>> 1. We no longer support 32-bit so that code could be elided.
>> 2. supports_cx8 is true for sparc so doesn't need to verified in sparc
>> specific code (it is intended for use in shared code).
>>
>> Cheers,
>> David
>>
>> On 26/08/2016 12:01 AM, Trevor Watson wrote:
>>> Hi All,
>>>
>>> Please can I get a review of these updates to sparc.ad which adds in the
>>> C2 compareAndExchange intriniscs for int, long, pointer and object?
>>>
>>> I've run the hotspot jtreg tests locally and the JPRT hotspot tests
>>> successfully.
>>>
>>> The implementation of these intrinsics gives a 9x to 20x performance
>>> improvement for compareAndExchange operatios.
>>>
>>> http://cr.openjdk.java.net/~alanbur/JDK-8141634/
>>>
>>> Thanks,
>>> Trevor