RFR (S): 8191567: Refactor ciInstanceKlass G1 keep alive barrier to use Access API.

[Erik Osterlund]

Hi Thomas,

> On 24 Nov 2017, at 18:01, Thomas Schatzl <thomas.schatzl at oracle.com> wrote:
> 
> Hi,
> 
>> On Fri, 2017-11-24 at 17:22 +0100, Erik Österlund wrote:
>> Hi,
>> 
>> When creating a ciInstanceKlass handle, G1 might need a SATB barrier
>> to keep "peeked" weak klass pointers alive during marking.
>> This should now be done with the Access API instead of manual calls
>> to the G1 SATB barrier.
>> 
>> Bug:
>> https://bugs.openjdk.java.net/browse/JDK-8191567
>> 
>> Webrev:
>> http://cr.openjdk.java.net/~eosterlund/8191567/webrev.00/
> 
>  looks good.

Thanks for the review!

> Thanks for providing such nice usage examples for the new Access klass
> separately from the huge Access change :)
> 

No problem! :)

Thanks,
/Erik

> Thanks,
>  Thomas
>