hg: jdk9/sandbox/hotspot: 8179678: ArrayCopy with same src and dst can cause incorrect execution or compiler crash

[chris.hegarty at oracle.com]

Changeset: 3ee42d818496
Author:    roland
Date:      2017-06-02 09:08 +0200
URL:       http://hg.openjdk.java.net/jdk9/sandbox/hotspot/rev/3ee42d818496

8179678: ArrayCopy with same src and dst can cause incorrect execution or compiler crash
Summary: Replacing load on dst with load on src only valid if copy doesn't modify src element to load
Reviewed-by: kvn, thartmann

! src/share/vm/opto/arraycopynode.cpp
! src/share/vm/opto/arraycopynode.hpp
! src/share/vm/opto/macro.cpp
! src/share/vm/opto/macroArrayCopy.cpp
! src/share/vm/opto/memnode.cpp
+ test/compiler/arraycopy/TestACSameSrcDst.java