RFR 8191278: MappedByteBuffer bulk access memory failures are not handled gracefully

[Harold Seigel]

Hi,

Please review this fix for JDK-8191278.  The fix uses the 
GuardUnsafeAccess class in unsafe.cpp so that the signal handler will 
know to convert SIGBUS signals to exceptions.

The compiler related changes and much of the test were written by 
Jamsheesh (jcm).

Open Webrev: 
http://cr.openjdk.java.net/~hseigel/bug_8191278/webrev/index.html

JBS Bug:  https://bugs.openjdk.java.net/browse/JDK-8191278

The fix was tested on Linux x64, Mac OS, Solaris Sparc, and Windows.  
Testing was not done on the other platforms changed by this fix.

The fix was regression tested by running Mach5 tiers 1 and 2 tests and 
builds on Linux x64, Solaris, Windows, and Mac OS X, by running Mach5 
tiers 3 -5 on Linux x64, and by running JCK-13 Lang and VM tests on 
Linux x64.

Thanks, Harold