Mercurial > hg > graal-compiler
view src/share/vm/ci/ciNullObject.hpp @ 2149:7e37af9d69ef
7011379: G1: overly long concurrent marking cycles
Summary: This changeset introduces filtering of SATB buffers at the point when they are about to be enqueued. If this filtering clears enough entries on each buffer, the buffer can then be re-used and not enqueued. This cuts down the number of SATB buffers that need to be processed by the concurrent marking threads.
Reviewed-by: johnc, ysr
author | tonyp |
---|---|
date | Wed, 19 Jan 2011 09:35:17 -0500 |
parents | f95d63e2154a |
children |
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/* * Copyright (c) 1999, 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. * */ #ifndef SHARE_VM_CI_CINULLOBJECT_HPP #define SHARE_VM_CI_CINULLOBJECT_HPP #include "ci/ciClassList.hpp" #include "ci/ciObject.hpp" #include "ci/ciUtilities.hpp" // ciNullObject // // This class represents a null reference in the VM. class ciNullObject : public ciObject { CI_PACKAGE_ACCESS private: ciNullObject() : ciObject() {} const char* type_string() { return "ciNullObject"; } void print_impl(outputStream* st); public: // Is this ciObject a Java Language Object? That is, // is the ciObject an instance or an array bool is_java_object() { return true; } // What kind of ciObject is this? bool is_null_object() const { return true; } bool is_classless() const { return true; } // Get the distinguished instance of this klass. static ciNullObject* make(); }; #endif // SHARE_VM_CI_CINULLOBJECT_HPP