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

[Trevor Watson]

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.

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