Please review (S) 6760773: UseCompressedOops is broken with UseParNewGC

[Coleen Phillimore - Sun Microsystems]

The load was sign extending the compressed oop when running with very 
large Java heap, so that the compare with super class list for casting 
was failing.  This causes ClassCastException with specjvm98.  
UseParNewGC was coincidental - just caues the oop to have sign bit set 
that we're looking for.

Webrev: http://webrev.invokedynamic.info/coleenp/6760773
(internal) bug id: http://monaco.sfbay.sun.com/detail.jsf?cr=6760773

Thanks,
Coleen