/* * Copyright (c) 2007, 2011, 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. */ package com.sun.max.vm.layout; import com.sun.max.unsafe.*; import com.sun.max.vm.actor.holder.*; import com.sun.max.vm.actor.member.*; import com.sun.max.vm.layout.Layout.HeaderField; /** * A hub is like a tuple and a word array at the same time. * Fields and word array elements overlap. * All fields are concentrated in a bounded area of the word array, * which starts at array offset zero. * There is a fixed array index from which on there are no more fields. */ public interface HybridLayout extends TupleLayout, ArrayLayout { int firstAvailableWordArrayIndex(Size tupleSize); /** * The resulting size must be aligned with a word array size. */ Size layoutFields(ClassActor superClassActor, FieldActor[] fieldActors); /** * Gets the header fields of this hybrid object layout. * * @return an array of header field descriptors sorted by ascending order of the field addresses in memory */ HeaderField[] headerFields(); }