RFR: JDK-8064473 - Improved handling of age during object copy in G1

[Thomas Schatzl]

Hi,

On Tue, 2014-11-11 at 17:25 +0100, Staffan Friberg wrote:
> Hi,
> 
> Small update to object copying in G1 to reduce the number of times age 
> has to be read and also make sure the markOop can be trusted by reading 
> and saving it prior doing the forwarded check. This change is broken out 
> from the PLAB event RFE.
> 
> bug: https://bugs.openjdk.java.net/browse/JDK-8064473
> webrev: http://cr.openjdk.java.net/~sfriberg/JDK-8064473/webrev.01

Looks good except for a minor nit: the comment at line  203

        // in this case, we have to install the mark word first,
        // otherwise obj looks to be forwarded (the old mark word,

should start with a capital letter.

I also created an RFE to fix up markOopDesc to allow nicer method names than "oop_decode_pointer", https://bugs.openjdk.java.net/browse/JDK-8064885

Thanks,
  Thomas