RFR 8245289: Clean up offset code in JavaClasses

[Frederic Parain]

Coleen,

This is a huge patch, fortunately most of the changes are
related to the removal of the _in_bytes suffix and the encapsulation
of fields and were easy to review.

javaClasses.hpp/javaClasses.hpp: a lot of changes and code refactoring
there, that are not easy to track with a webrev. Most changes make the
code cleaner. However, there’re some inconsistencies on static fields
declaration: some are initialized with an explicit value, others are
not, and I’m not seeing a clear rule why.

Otherwise, looks good.

Regards,

Fred


> On May 28, 2020, at 08:48, coleen.phillimore at oracle.com wrote:
> 
> Summary: Make offset member names consistent and private, move static initializations near owning classes
> 
> This one is better.  I gave up on the X macros because they didn't save typing.  The changes here were to add underscores to offset field names, remove _in_bytes for offset accessors and add asserts that the offset is non-zero, made java_lang_ref_Reference offset fields private, and moved static member definitions closer to the class instead of some random place in javaClasses.cpp.
> 
> See discussion for 8243996 Remove hardcoded field offsets for more details. https://mail.openjdk.java.net/pipermail/hotspot-dev/2020-May/041732.html
> 
> Tested with tier1-6.
> 
> open webrev at http://cr.openjdk.java.net/~coleenp/2020/8245289.01/webrev
> bug link https://bugs.openjdk.java.net/browse/JDK-8245289
> 
> Thanks,
> Coleen