hg: jdk10/hs/hotspot: 8176506: C2: loop unswitching and unsafe accesses cause crash

[vladimir.kozlov at oracle.com]

Changeset: df318ded5778
Author:    roland
Date:      2017-05-29 18:17 +0200
URL:       http://hg.openjdk.java.net/jdk10/hs/hotspot/rev/df318ded5778

8176506: C2: loop unswitching and unsafe accesses cause crash
Reviewed-by: vlivanov, mcberg, kvn, simonis

! src/cpu/aarch64/vm/aarch64.ad
! src/cpu/arm/vm/arm.ad
! src/cpu/arm/vm/assembler_arm_32.hpp
! src/cpu/arm/vm/assembler_arm_64.hpp
! src/cpu/x86/vm/assembler_x86.cpp
! src/cpu/x86/vm/assembler_x86.hpp
! src/cpu/x86/vm/x86.ad
! src/share/vm/opto/castnode.cpp
! src/share/vm/opto/castnode.hpp
! src/share/vm/opto/classes.hpp
! src/share/vm/opto/escape.cpp
! src/share/vm/opto/escape.hpp
! src/share/vm/opto/graphKit.cpp
! src/share/vm/opto/graphKit.hpp
! src/share/vm/opto/library_call.cpp
! src/share/vm/opto/macro.cpp
! src/share/vm/opto/opaquenode.cpp
! src/share/vm/opto/opaquenode.hpp
+ test/compiler/unsafe/TestMaybeNullUnsafeAccess.java