hotspot/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/memory/MemoryAnchorNode.java

/*
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 * 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.
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package org.graalvm.compiler.nodes.memory;

import static org.graalvm.compiler.nodeinfo.InputType.Memory;
import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_0;
import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_0;

import org.graalvm.compiler.core.common.type.StampFactory;
import org.graalvm.compiler.graph.Node;
import org.graalvm.compiler.graph.NodeClass;
import org.graalvm.compiler.graph.spi.Canonicalizable;
import org.graalvm.compiler.graph.spi.CanonicalizerTool;
import org.graalvm.compiler.nodeinfo.NodeInfo;
import org.graalvm.compiler.nodeinfo.StructuralInput.Memory;
import org.graalvm.compiler.nodes.FixedWithNextNode;
import org.graalvm.compiler.nodes.spi.LIRLowerable;
import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool;

@NodeInfo(allowedUsageTypes = Memory, cycles = CYCLES_0, size = SIZE_0)
public final class MemoryAnchorNode extends FixedWithNextNode implements LIRLowerable, MemoryNode, Canonicalizable {

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

    public MemoryAnchorNode() {
        super(TYPE, StampFactory.forVoid());
    }

    @Override
    public void generate(NodeLIRBuilderTool generator) {
        // Nothing to emit, since this node is used for structural purposes only.
    }

    @Override
    public Node canonical(CanonicalizerTool tool) {
        return tool.allUsagesAvailable() && hasNoUsages() ? null : this;
    }

    @NodeIntrinsic
    public static native Memory anchor();
}