/*

 * 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.java;

import java.util.Collections;

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

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

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

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

import org.graalvm.compiler.graph.NodeClass;

import org.graalvm.compiler.graph.spi.Simplifiable;

import org.graalvm.compiler.graph.spi.SimplifierTool;

import org.graalvm.compiler.nodeinfo.NodeInfo;

import org.graalvm.compiler.nodes.ConstantNode;

import org.graalvm.compiler.nodes.FixedGuardNode;

import org.graalvm.compiler.nodes.FrameState;

import org.graalvm.compiler.nodes.LogicNode;

import org.graalvm.compiler.nodes.NodeView;

import org.graalvm.compiler.nodes.ValueNode;

import org.graalvm.compiler.nodes.calc.CompareNode;

import org.graalvm.compiler.nodes.spi.VirtualizableAllocation;

import org.graalvm.compiler.nodes.spi.VirtualizerTool;

import org.graalvm.compiler.nodes.util.GraphUtil;

import org.graalvm.compiler.nodes.virtual.VirtualArrayNode;

import org.graalvm.compiler.nodes.virtual.VirtualObjectNode;

import jdk.vm.ci.meta.DeoptimizationAction;

import jdk.vm.ci.meta.DeoptimizationReason;

import jdk.vm.ci.meta.ResolvedJavaType;

/**

 * The {@code NewArrayNode} is used for all array allocations where the element type is know at

 * compile time.

 */

// JaCoCo Exclude

@NodeInfo

public class NewArrayNode extends AbstractNewArrayNode implements VirtualizableAllocation, Simplifiable {

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

    private final ResolvedJavaType elementType;

    public NewArrayNode(ResolvedJavaType elementType, ValueNode length, boolean fillContents) {

        this(elementType, length, fillContents, null);

    }

    public NewArrayNode(ResolvedJavaType elementType, ValueNode length, boolean fillContents, FrameState stateBefore) {

        this(TYPE, elementType, length, fillContents, stateBefore);

    }

    protected NewArrayNode(NodeClass<? extends NewArrayNode> c, ResolvedJavaType elementType, ValueNode length, boolean fillContents, FrameState stateBefore) {

        super(c, StampFactory.objectNonNull(TypeReference.createExactTrusted(elementType.getArrayClass())), length, fillContents, stateBefore);

        this.elementType = elementType;

    }

    @NodeIntrinsic

    private static native Object newArray(@ConstantNodeParameter Class<?> elementType, int length, @ConstantNodeParameter boolean fillContents);

    public static Object newUninitializedArray(Class<?> elementType, int length) {

        return newArray(elementType, length, false);

    }

    /**

     * Gets the element type of the array.

     *

     * @return the element type of the array

     */

    public ResolvedJavaType elementType() {

        return elementType;

    }

    @Override

    public void virtualize(VirtualizerTool tool) {

        ValueNode lengthAlias = tool.getAlias(length());

        if (lengthAlias.asConstant() != null) {

            int constantLength = lengthAlias.asJavaConstant().asInt();

            if (constantLength >= 0 && constantLength < tool.getMaximumEntryCount()) {

                ValueNode[] state = new ValueNode[constantLength];

                ConstantNode defaultForKind = constantLength == 0 ? null : defaultElementValue();

                for (int i = 0; i < constantLength; i++) {

                    state[i] = defaultForKind;

                }

                VirtualObjectNode virtualObject = createVirtualArrayNode(constantLength);

                tool.createVirtualObject(virtualObject, state, Collections.<MonitorIdNode> emptyList(), false);

                tool.replaceWithVirtual(virtualObject);

            }

        }

    }

    protected VirtualArrayNode createVirtualArrayNode(int constantLength) {

        return new VirtualArrayNode(elementType(), constantLength);

    }

    /* Factored out in a separate method so that subclasses can override it. */

    protected ConstantNode defaultElementValue() {

        return ConstantNode.defaultForKind(elementType().getJavaKind(), graph());

    }

    @Override

    public void simplify(SimplifierTool tool) {

        if (hasNoUsages()) {

            NodeView view = NodeView.from(tool);

            Stamp lengthStamp = length().stamp(view);

            if (lengthStamp instanceof IntegerStamp) {

                IntegerStamp lengthIntegerStamp = (IntegerStamp) lengthStamp;

                if (lengthIntegerStamp.isPositive()) {

                    GraphUtil.removeFixedWithUnusedInputs(this);

                    return;

                }

            }

            // Should be areFrameStatesAtSideEffects but currently SVM will complain about

            // RuntimeConstraint

            if (graph().getGuardsStage().allowsFloatingGuards()) {

                // we do not have a non-deopting path for that at the moment so action=None.

                FixedGuardNode guard = graph().add(new FixedGuardNode(lengthNegativeCondition, DeoptimizationReason.RuntimeConstraint, DeoptimizationAction.None, true));

                graph().replaceFixedWithFixed(this, guard);

            }

        }

    }

}