[12] RFR(XXS): JDK-8196950: AARCH64 - Add VM flags presets for Cavium Thunder X2 CPU

[Dmitry Chuyko]

Hello,

Please review small defaults correction.

rfe: https://bugs.openjdk.java.net/browse/JDK-8196950
code:

diff -r 16950b2eaebf src/hotspot/cpu/aarch64/vm_version_aarch64.cpp
--- a/src/hotspot/cpu/aarch64/vm_version_aarch64.cpp    Tue Oct 30 
09:13:00 2018 -0400
+++ b/src/hotspot/cpu/aarch64/vm_version_aarch64.cpp    Wed Oct 31 
20:33:41 2018 +0300
@@ -219,7 +219,7 @@
      }
  #ifdef COMPILER2
      if (FLAG_IS_DEFAULT(UseFPUForSpilling)) {
-      FLAG_SET_DEFAULT(UseFPUForSpilling, true);
+      FLAG_SET_DEFAULT(UseFPUForSpilling, false);
      }
  #endif
    }

Having "-XX:+AvoidUnalignedAccesses -XX:+UseSIMDForMemoryOps 
-XX:-UseFPUForSpilling" as a default works (in general) better for 
SPECjvm and SPECjbb.

-Dmitry