RFR: 8166583: Add oopDesc::klass_or_null_acquire()

[David Holmes]

Looks good.

Thanks,
David

On 23/09/2016 6:51 AM, Kim Barrett wrote:
> Please review this addition of a new function to oopDesc.  This is a
> variant of an existing function; the new function provides acquire
> semantics to the access.
>
> This is a subtask of JDK-8160369, providing additional infrastructure
> needed to fix that bug.
>
> CR:
> https://bugs.openjdk.java.net/browse/JDK-8166583
>
> Webrev:
> http://cr.openjdk.java.net/~kbarrett/8166583/webrev.00/
>
> Testing:
> Ran nightly tests with this being used by an in-development fix for
> part of JDK-8160369.
>