RFR: 8205559: Remove IN_CONCURRENT_ROOT Access decorator

[Per Liden]

On 06/24/2018 11:51 PM, Kim Barrett wrote:
> Please review the removal of the IN_CONCURRENT_ROOT Access decorator.
> 
> All non-AS_RAW IN_NATIVE accesses will be treated as potentially
> concurrent, and so will require barriers appropriate to the selected
> collector.
> 
> Renumbered the Access decorators, eliminating gaps and mis-orderings
> that had accrued from previous removals and renamings.
> 
> Fixed StringDedupTable::lookup usage of the Access API.  It was using
> IN_CONCURRENT_ROOT incorrectly, and was not using AS_NO_KEEPALIVE
> where it should have been.  There are other places where this class is
> not using the Access API but should be, involving the _obj field of
> StringDedupTableEntry; addressing those will be part of a future CR,
> since currently only ZGC would fail because of these and ZGC does not
> yet support string deduplication.
> 
> CR:
> https://bugs.openjdk.java.net/browse/JDK-8205559
> 
> Webrev:
> http://cr.openjdk.java.net/~kbarrett/8205559/open.00/

Looks good to me!

/Per

> 
> Testing:
> Mach5 tier1,2,3, hs-tier4,5
> 
> Aurora perf testing for G1 and Parallel detected no performance regressions.
>