/*

 * Copyright (c) 2012, 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.hotspot.nodes;

import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_2;

import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_1;

import java.util.BitSet;

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

import org.graalvm.compiler.graph.NodeClass;

import org.graalvm.compiler.lir.VirtualStackSlot;

import org.graalvm.compiler.nodeinfo.NodeInfo;

import org.graalvm.compiler.nodes.FixedWithNextNode;

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

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

import org.graalvm.compiler.word.Word;

import org.graalvm.compiler.word.WordTypes;

import jdk.vm.ci.meta.JavaKind;

import jdk.vm.ci.meta.Value;

/**

 * Reserves a block of memory in the stack frame of a method. The block is reserved in the frame for

 * the entire execution of the associated method.

 */

@NodeInfo(cycles = CYCLES_2, size = SIZE_1)

public final class AllocaNode extends FixedWithNextNode implements LIRLowerable {

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

    /**

     * The number of slots in block.

     */

    protected final int slots;

    /**

     * The indexes of the object pointer slots in the block. Each such object pointer slot must be

     * initialized before any safepoint in the method otherwise the garbage collector will see

     * garbage values when processing these slots.

     */

    protected final BitSet objects;

    public AllocaNode(@InjectedNodeParameter WordTypes wordTypes, int slots) {

        this(slots, wordTypes.getWordKind(), new BitSet());

    }

    public AllocaNode(int slots, JavaKind wordKind, BitSet objects) {

        super(TYPE, StampFactory.forKind(wordKind));

        this.slots = slots;

        this.objects = objects;

    }

    @Override

    public void generate(NodeLIRBuilderTool gen) {

        VirtualStackSlot array = gen.getLIRGeneratorTool().getResult().getFrameMapBuilder().allocateStackSlots(slots, objects, null);

        Value result = gen.getLIRGeneratorTool().emitAddress(array);

        gen.setResult(this, result);

    }

    @NodeIntrinsic

    public static native Word alloca(@ConstantNodeParameter int slots);

}