Mercurial > hg > graal-jvmci-8
view src/share/vm/oops/markOop.cpp @ 2243:f77b3ec064b0
Merge
author | rottenha |
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date | Mon, 21 Feb 2011 04:49:17 -0800 |
parents | f95d63e2154a |
children | f08d439fab8c |
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/* * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "oops/markOop.hpp" #ifdef TARGET_OS_FAMILY_linux # include "thread_linux.inline.hpp" #endif #ifdef TARGET_OS_FAMILY_solaris # include "thread_solaris.inline.hpp" #endif #ifdef TARGET_OS_FAMILY_windows # include "thread_windows.inline.hpp" #endif void markOopDesc::print_on(outputStream* st) const { if (is_locked()) { st->print("locked(0x%lx)->", value()); markOop(*(markOop*)value())->print_on(st); } else { assert(is_unlocked() || has_bias_pattern(), "just checking"); st->print("mark("); if (has_bias_pattern()) st->print("biased,"); st->print("hash %#lx,", hash()); st->print("age %d)", age()); } } // Give advice about whether the oop that contains this markOop // should be cached or not. bool markOopDesc::should_not_be_cached() const { // the cast is because decode_pointer() isn't marked const if (is_marked() && ((markOopDesc *)this)->decode_pointer() != NULL) { // If the oop containing this markOop is being forwarded, then // we are in the middle of GC and we do not want the containing // oop to be added to a cache. We have no way of knowing whether // the cache has already been visited by the current GC phase so // we don't know whether the forwarded oop will be properly // processed in this phase. If the forwarded oop is not properly // processed, then we'll see strange crashes or asserts during // the next GC run because the markOop will contain an unexpected // value. // // This situation has been seen when we are GC'ing a methodOop // because we use the methodOop while we're GC'ing it. Scary // stuff. Some of the uses the methodOop cause the methodOop to // be added to the OopMapCache in the instanceKlass as a side // effect. This check lets the cache maintainer know when a // cache addition would not be safe. return true; } // caching the containing oop should be just fine return false; }