hg: jdk/sandbox: 8225776: Optimize branch frequency of G1's write post-barrier in C2

[chris.hegarty at oracle.com]

Changeset: b5ab9a71aa95
Author:    manc
Date:      2019-08-05 13:18 -0700
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/b5ab9a71aa95

8225776: Optimize branch frequency of G1's write post-barrier in C2
Reviewed-by: tschatzl, dlong
Contributed-by: Man Cao <manc at google.com>, Chuck Rasbold <rasbold at google.com>

! src/hotspot/share/gc/g1/c2/g1BarrierSetC2.cpp