RFR: JDK-8160285: Bootcycle builds are broken on jdk9/hs for windows i586

[Erik Joelsson]

Hello,

When doing a bootcycle build for a 32bit target, but using a 64bit 
bootjdk, the JVM memory arguments found suitable for the 64bit bootjdk 
are still used when running the bootcycle part of the build. When using 
a 32bit bootjdk, we limit the mx flag to 1100M while a 64bit bootjdk 
gets 1600M. So far, the 32bit JDK 9 Hotspot has been able to cope with 
-Xmx1600M, but it has now started to fail on Windows. While that may be 
a bug to investigate on its own, the build has not reason for requiring 
such big heaps from a 32bit JVM.

This patch adds more special treatment in the bootcycle-spec for when 
building a 32bit target that makes sure the 32bit JVM gets at most 
mx1100M. I would like to push this to jdk9/dev ASAP to avoid the 
bootcycle build breaking when jdk9/hs next gets integrated.

Bug: https://bugs.openjdk.java.net/browse/JDK-8160285
Webrev: http://cr.openjdk.java.net/~erikj/8160285/webrev.top.01/

/Erik