RFR: 8188858: Caching latestUserDefinedLoader() results in ObjectInputStream.readObject()

[Kazunori Ogata]

Hi all,

Please review a change for JDK-8188858.

Bug report: https://bugs.openjdk.java.net/browse/JDK-8188858
Webrev: http://cr.openjdk.java.net/~horii/8188858/webrev.00/

This change caches the result of latestUserDefinedLoader() when objects 
are deserialized, so the decerializer can avoid redundant stack walking to 
resolve classes of deserializing objects.  This change improved maxjOPS of 
SPECjbb2015 by 6% on a POWER8 machine.


Regards,
Ogata