RFR (S): 8199567: [Nestmates] Cleanup instanceKlass.cpp

[David Holmes]

Hi Lois,

On 23/10/2018 10:14 PM, Lois Foltan wrote:
> On 10/22/2018 11:43 PM, David Holmes wrote:
> 
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8199567
>> Webrev: http://cr.openjdk.java.net/~dholmes/8199567/webrev/
>>
>> This is a simple "cleanup" previously suggested by John Rose for 
>> checking nest membership. Rather than checking for name equality and 
>> then checking the loaded class, we check if there's a loaded class 
>> first and if not fallback to the name check. This favours the case 
>> where the nestmate classes are already resolved and loaded.
> 
> Hi David,
> 
> Looks good.  One comment:

Thanks for looking at it!

> oops/instanceKlass.cpp:
> - line #173: Consider changing the if conditional to "if 
> (_constants->tag_at(cp_index).is_klass())"
> 
> I believe the "is_klass()" method is the preferred way to compare a tag 
> to JVM_CONSTANT_Class.

Sure - webrev updated:

http://cr.openjdk.java.net/~dholmes/8199567/webrev.v2/

Thanks,
David

> Thanks,
> Lois
> 
>>
>> There was no observable performance difference.
>>
>> Testing: mach5 tiers 1-3 including nestmate tests
>>
>> Thanks,
>> David
>