RFR: 8157841: aarch64: prefetch ignores cache line size

[Edward Nevill]

Hi,

Please review the following webrev

http://cr.openjdk.java.net/~enevill/8157841/webrev

The aarch64 implementation ignores the actual dcache line size and sets the various prefetch variables based on an assumed cache line size of 64.

One of our partners has a cache line size of 128.

The above patch reads the cache line size from the ctr_el0 register and sets the prefetch variables based on multiples of that instead.

Regards,
Ed.