/*
 * Copyright (c) 2009, 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.oracle.graal.nodes;

import com.oracle.graal.api.code.*;
import com.oracle.graal.api.meta.*;
import com.oracle.graal.graph.*;
import com.oracle.graal.nodes.spi.*;
import com.oracle.graal.nodes.type.*;

/**
 * This node represents an unconditional explicit request for immediate deoptimization.
 * 
 * After this node, execution will continue using a fallback execution engine (such as an
 * interpreter) at the position described by the {@link #getDeoptimizationState() deoptimization
 * state}.
 * 
 */
@NodeInfo(shortName = "Deopt", nameTemplate = "Deopt {p#reason/s}")
public class DeoptimizeNode extends ControlSinkNode implements Node.IterableNodeType, Lowerable, LIRLowerable, DeoptimizingNode {

    @Input private FrameState deoptState;

    private final DeoptimizationAction action;
    private final DeoptimizationReason reason;

    public DeoptimizeNode(DeoptimizationAction action, DeoptimizationReason reason) {
        super(StampFactory.forVoid());
        this.action = action;
        this.reason = reason;
    }

    public DeoptimizationAction action() {
        return action;
    }

    public DeoptimizationReason reason() {
        return reason;
    }

    @Override
    public void lower(LoweringTool tool, LoweringType loweringType) {
        tool.getRuntime().lower(this, tool);
    }

    @Override
    public void generate(LIRGeneratorTool gen) {
        gen.emitDeoptimize(action, this);
    }

    @NodeIntrinsic
    public static native void deopt(@ConstantNodeParameter DeoptimizationAction action, @ConstantNodeParameter DeoptimizationReason reason);

    @Override
    public boolean canDeoptimize() {
        return true;
    }

    @Override
    public FrameState getDeoptimizationState() {
        return deoptState;
    }

    @Override
    public void setDeoptimizationState(FrameState f) {
        updateUsages(deoptState, f);
        deoptState = f;
    }

    @Override
    public DeoptimizationReason getDeoptimizationReason() {
        return reason;
    }
}