/*

 * 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.lang.ref.Reference;

import java.util.Collections;

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.nodeinfo.NodeInfo;

import org.graalvm.compiler.nodes.ConstantNode;

import org.graalvm.compiler.nodes.FrameState;

import org.graalvm.compiler.nodes.ValueNode;

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

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

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

import jdk.vm.ci.meta.ResolvedJavaField;

import jdk.vm.ci.meta.ResolvedJavaType;

/**

 * The {@code NewInstanceNode} represents the allocation of an instance class object.

 */

@NodeInfo(nameTemplate = "New {p#instanceClass/s}")

public class NewInstanceNode extends AbstractNewObjectNode implements VirtualizableAllocation {

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

    protected final ResolvedJavaType instanceClass;

    public NewInstanceNode(ResolvedJavaType type, boolean fillContents) {

        this(TYPE, type, fillContents, null);

    }

    public NewInstanceNode(ResolvedJavaType type, boolean fillContents, FrameState stateBefore) {

        this(TYPE, type, fillContents, stateBefore);

    }

    protected NewInstanceNode(NodeClass<? extends NewInstanceNode> c, ResolvedJavaType type, boolean fillContents, FrameState stateBefore) {

        super(c, StampFactory.objectNonNull(TypeReference.createExactTrusted(type)), fillContents, stateBefore);

        assert !type.isArray() && !type.isInterface() && !type.isPrimitive() && !type.isAbstract();

        this.instanceClass = type;

    }

    /**

     * Gets the instance class being allocated by this node.

     *

     * @return the instance class allocated

     */

    public ResolvedJavaType instanceClass() {

        return instanceClass;

    }

    @Override

    public void virtualize(VirtualizerTool tool) {

        /*

         * Reference objects can escape into their ReferenceQueue at any safepoint, therefore

         * they're excluded from escape analysis.

         */

        if (!tool.getMetaAccess().lookupJavaType(Reference.class).isAssignableFrom(instanceClass)) {

            VirtualInstanceNode virtualObject = createVirtualInstanceNode(true);

            ResolvedJavaField[] fields = virtualObject.getFields();

            ValueNode[] state = new ValueNode[fields.length];

            for (int i = 0; i < state.length; i++) {

                state[i] = defaultFieldValue(fields[i]);

            }

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

            tool.replaceWithVirtual(virtualObject);

        }

    }

    protected VirtualInstanceNode createVirtualInstanceNode(boolean hasIdentity) {

        return new VirtualInstanceNode(instanceClass(), hasIdentity);

    }

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

    protected ConstantNode defaultFieldValue(ResolvedJavaField field) {

        return ConstantNode.defaultForKind(field.getType().getJavaKind(), graph());

    }

}