Review Request: Zero S/390 fixes

[Gary Benson]

Hi all,

This webrev fixes two failures on 31-bit S/390:

  http://cr.openjdk.java.net/~gbenson/zero-s390-fixes-01/

The first is that there were not enough shadow pages for a
StackOverflowError to be thrown.  The second is the
implementation of a 64-bit atomic copy such that long and
double fields in objects are got and set atomically.

I don't have a bug id for this.

Cheers,
Gary

-- 
http://gbenson.net/