Request for reviews (S): 6998985: faulty generic arraycopy on windows x86_64: 4th arg overwritten with oop

[Christian Thalinger]

http://cr.openjdk.java.net/~twisti/6998985/webrev.01/

6998985: faulty generic arraycopy on windows x86_64: 4th arg  
overwritten with oop
Reviewed-by:

There is a problem concerning generic arraycopy on windows x86_64.  On
windows, the stub gets its 4th argument in register r9.  The register
gets overwritten by an oop.  In most cases, the subsequent range check
will fail and the copy will be done over the slow path.  However,
depending on the oops address, the range check might succeed and the
copy lead to wrong results.

Tested with failing testcase.