/*

 * Copyright (c) 2009, 2015, 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 org.graalvm.compiler.nodes;

import java.util.Map;

import org.graalvm.compiler.core.common.type.Stamp;

import org.graalvm.compiler.core.common.type.StampFactory;

import org.graalvm.compiler.graph.NodeClass;

import org.graalvm.compiler.graph.NodeInputList;

import org.graalvm.compiler.nodeinfo.NodeInfo;

import org.graalvm.compiler.nodes.type.StampTool;

import org.graalvm.util.CollectionsUtil;

/**

 * Value {@link PhiNode}s merge data flow values at control flow merges.

 */

@NodeInfo(nameTemplate = "Phi({i#values}, {p#valueDescription})")

    public static final NodeClass<ValuePhiNode> TYPE = NodeClass.create(ValuePhiNode.class);

    @Input protected NodeInputList<ValueNode> values;

    public ValuePhiNode(Stamp stamp, AbstractMergeNode merge) {

        this(TYPE, stamp, merge);

    }

    protected ValuePhiNode(NodeClass<? extends ValuePhiNode> c, Stamp stamp, AbstractMergeNode merge) {

        super(c, stamp, merge);

        assert stamp != StampFactory.forVoid();

        values = new NodeInputList<>(this);

    }

    public ValuePhiNode(Stamp stamp, AbstractMergeNode merge, ValueNode[] values) {

        super(TYPE, stamp, merge);

        assert stamp != StampFactory.forVoid();

        this.values = new NodeInputList<>(this, values);

    }

    @Override

    public NodeInputList<ValueNode> values() {

        return values;

    }

    @Override

    public boolean inferStamp() {

        /*

         * Meet all the values feeding this Phi but don't use the stamp of this Phi since that's

         * what's being computed.

         */

        Stamp valuesStamp = StampTool.meetOrNull(values(), this);

        if (valuesStamp == null) {

            valuesStamp = stamp;

        } else if (stamp.isCompatible(valuesStamp)) {

            valuesStamp = stamp.join(valuesStamp);

        }

        return updateStamp(valuesStamp);

    }

    @Override

    public boolean verify() {

        Stamp s = null;

        for (ValueNode input : values()) {

            assert input != null;

            if (s == null) {

                s = input.stamp(NodeView.DEFAULT);

            } else {

                if (!s.isCompatible(input.stamp(NodeView.DEFAULT))) {

                    fail("Phi Input Stamps are not compatible. Phi:%s inputs:%s", this,

                                    CollectionsUtil.mapAndJoin(values(), x -> x.toString() + ":" + x.stamp(NodeView.DEFAULT), ", "));

                }

            }

        }

        return super.verify();

    }

    @Override

    protected String valueDescription() {

        return stamp(NodeView.DEFAULT).unrestricted().toString();

    }

    @Override

    public Map<Object, Object> getDebugProperties(Map<Object, Object> map) {

        Map<Object, Object> properties = super.getDebugProperties(map);

        properties.put("valueDescription", valueDescription());

        return properties;

    }

}