[aarch64-port-dev ] RFR: 8075930: AARCH64: Use FP Register in C2

[Andrew Haley]

Looking at this thread:

http://mail.openjdk.java.net/pipermail/hotspot-compiler-dev/2014-December/016477.html
https://bugs.openjdk.java.net/browse/JDK-8068945

I'm wondering if we should keep FP as a frame pointer.  We'd have a
slightly more complex method entry sequence, but the profiling and
debugging advantages look to be quite considerable.

Andrew.