hg: shenandoah/jdk: Cherry-pick: 8213489: GC/C2 abstraction for Compile::final_graph_reshaping() plus Shenandoah parts

[roman at kennke.org]

Changeset: 196048166f09
Author:    rkennke
Date:      2018-11-09 10:38 +0100
URL:       http://hg.openjdk.java.net/shenandoah/jdk/rev/196048166f09

Cherry-pick: 8213489: GC/C2 abstraction for Compile::final_graph_reshaping() plus Shenandoah parts

! src/hotspot/share/gc/shared/c2/barrierSetC2.hpp
! src/hotspot/share/gc/shenandoah/c2/shenandoahBarrierSetC2.cpp
! src/hotspot/share/gc/shenandoah/c2/shenandoahBarrierSetC2.hpp
! src/hotspot/share/gc/z/c2/zBarrierSetC2.cpp
! src/hotspot/share/gc/z/c2/zBarrierSetC2.hpp
! src/hotspot/share/opto/compile.cpp
! src/hotspot/share/opto/compile.hpp