RFR: 8163589: Add back intrinsic methods for event based tracing

[Robbin Ehn]

Hi again, please review!

Fortunately I saw that I had missed a logical change (from 8 to 9) how 
class id is retrieved, sorry about that.
Instead of masking away the two low bits, we use an arbitrary mask and 
an arbitrary right shift.

Here is the incremental::
http://cr.openjdk.java.net/~rehn/8163589/hotspot.02-03/
with full here:
http://cr.openjdk.java.net/~rehn/8163589/hotspot.03/

Tested with JMH and relevant RBT test group.

Thanks!

/Robbin

On 08/10/2016 04:05 PM, Robbin Ehn wrote:
> Hi all,
>
> In 8 we had this intrinsic, I'm adding it back
> Used for event based tracing.
>
> Webrev: http://cr.openjdk.java.net/~rehn/8163589/hotspot.01/webrev/
> Bug: https://bugs.openjdk.java.net/browse/JDK-8163589
>
> Thanks!
>
> /Robbin