hg: jdk/sandbox: 8224741: Optimize the scan area during the Scan Heap Roots phase

[chris.hegarty at oracle.com]

Changeset: 5919b273def6
Author:    tschatzl
Date:      2019-07-08 09:24 +0200
URL:       http://hg.openjdk.java.net/jdk/sandbox/rev/5919b273def6

8224741: Optimize the scan area during the Scan Heap Roots phase
Summary: When scanning card blocks, remember the last address already scanned. Continue scanning from this address.
Reviewed-by: kbarrett, lkorinth

! src/hotspot/share/gc/g1/g1RemSet.cpp
! src/hotspot/share/gc/g1/heapRegion.hpp
! src/hotspot/share/gc/g1/heapRegion.inline.hpp