001/*
002 * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation.
008 *
009 * This code is distributed in the hope that it will be useful, but WITHOUT
010 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
011 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
012 * version 2 for more details (a copy is included in the LICENSE file that
013 * accompanied this code).
014 *
015 * You should have received a copy of the GNU General Public License version
016 * 2 along with this work; if not, write to the Free Software Foundation,
017 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
018 *
019 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
020 * or visit www.oracle.com if you need additional information or have any
021 * questions.
022 */
023package com.oracle.graal.nodes;
024
025import com.oracle.graal.compiler.common.type.*;
026import com.oracle.graal.graph.*;
027import com.oracle.graal.graph.Node.ValueNumberable;
028import com.oracle.graal.nodeinfo.*;
029import com.oracle.graal.nodes.calc.*;
030import com.oracle.graal.nodes.extended.*;
031
032/**
033 * A proxy is inserted at loop exits for any value that is created inside the loop (i.e. was not
034 * live on entry to the loop) and is (potentially) used after the loop.
035 */
036@NodeInfo
037public abstract class ProxyNode extends FloatingNode implements IterableNodeType, ValueNumberable {
038
039    public static final NodeClass<ProxyNode> TYPE = NodeClass.create(ProxyNode.class);
040    @Input(InputType.Association) AbstractBeginNode proxyPoint;
041
042    protected ProxyNode(NodeClass<? extends ProxyNode> c, Stamp stamp, AbstractBeginNode proxyPoint) {
043        super(c, stamp);
044        assert proxyPoint != null;
045        this.proxyPoint = proxyPoint;
046    }
047
048    public abstract ValueNode value();
049
050    public AbstractBeginNode proxyPoint() {
051        return proxyPoint;
052    }
053
054    @Override
055    public boolean verify() {
056        assert !(value() instanceof ProxyNode) || ((ProxyNode) value()).proxyPoint != proxyPoint;
057        return super.verify();
058    }
059
060    public static ValueProxyNode forValue(ValueNode value, AbstractBeginNode exit, StructuredGraph graph) {
061        return graph.unique(new ValueProxyNode(value, exit));
062    }
063
064    public static GuardProxyNode forGuard(GuardingNode value, AbstractBeginNode exit, StructuredGraph graph) {
065        return graph.unique(new GuardProxyNode(value, exit));
066    }
067}