hg: jdk7/hotspot-rt/hotspot: 6716785: implicit null checks not triggering with CompressedOops

[coleen.phillimore at sun.com]

Changeset: 1fdb98a17101
Author:    coleenp
Date:      2008-07-19 17:38 -0400
URL:       http://hg.openjdk.java.net/jdk7/hotspot-rt/hotspot/rev/1fdb98a17101

6716785: implicit null checks not triggering with CompressedOops
Summary: allocate alignment-sized page(s) below java heap so that memory accesses at heap_base+1page give signal and cause an implicit null check
Reviewed-by: kvn, jmasa, phh, jcoomes

! src/os/linux/vm/os_linux.cpp
! src/os/solaris/vm/os_solaris.cpp
! src/os/windows/vm/os_windows.cpp
! src/os_cpu/linux_sparc/vm/assembler_linux_sparc.cpp
! src/os_cpu/linux_x86/vm/assembler_linux_x86_32.cpp
! src/os_cpu/linux_x86/vm/assembler_linux_x86_64.cpp
! src/os_cpu/solaris_sparc/vm/assembler_solaris_sparc.cpp
! src/os_cpu/solaris_x86/vm/assembler_solaris_x86_32.cpp
! src/os_cpu/solaris_x86/vm/assembler_solaris_x86_64.cpp
! src/os_cpu/windows_x86/vm/assembler_windows_x86_32.cpp
! src/os_cpu/windows_x86/vm/assembler_windows_x86_64.cpp
! src/share/vm/asm/assembler.cpp
! src/share/vm/gc_implementation/parallelScavenge/parMarkBitMap.cpp
! src/share/vm/gc_implementation/parallelScavenge/parallelScavengeHeap.cpp
! src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp
! src/share/vm/gc_implementation/parallelScavenge/psVirtualspace.cpp
! src/share/vm/memory/genCollectedHeap.cpp
! src/share/vm/prims/jni.cpp
! src/share/vm/runtime/arguments.cpp
! src/share/vm/runtime/os.cpp
! src/share/vm/runtime/os.hpp
! src/share/vm/runtime/virtualspace.cpp
! src/share/vm/runtime/virtualspace.hpp