review (XS): 7047491: C1: registers saved incorrectly when calling checkcast_arraycopy stub

[Igor Veresov]

Incorrect handling of the registers made runThese fail one of the 
arraycopy tests on 64bit windows with -d64 -Xcomp -XX:+TieredCompilation.

The problem is that when we call the checkcast_arraycopy stub we assume 
that it abides to C calling convention, but in fact it doesn't, so it 
can kill the registers containing arguments that are expected later by 
the slow stub. The easiest solution is to save argument registers before 
the call and then restore them.

Webrev: http://cr.openjdk.java.net/~iveresov/7047491/webrev.00/

Tested with JPRT by passing -XX:+TieredCompilation to every test.

igor