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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * 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).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package org.graalvm.compiler.hotspot.nodes;

import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_64;
import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_64;

import org.graalvm.compiler.graph.NodeClass;
import org.graalvm.compiler.nodeinfo.NodeInfo;
import org.graalvm.compiler.nodes.ValueNode;
import org.graalvm.compiler.nodes.memory.address.AddressNode;

The G1ReferentFieldReadBarrier is added when a read access is performed to the referent field of a Reference object (through a LoadFieldNode or an UnsafeLoadNode). The return value of the read is passed to the snippet implementing the read barrier and consequently is added to the SATB queue if the concurrent marker is enabled. /**
 * The {@code G1ReferentFieldReadBarrier} is added when a read access is performed to the referent
 * field of a {@link java.lang.ref.Reference} object (through a {@code LoadFieldNode} or an
 * {@code UnsafeLoadNode}). The return value of the read is passed to the snippet implementing the
 * read barrier and consequently is added to the SATB queue if the concurrent marker is enabled.
 */
@NodeInfo(cycles = CYCLES_64, size = SIZE_64)
public final class G1ReferentFieldReadBarrier extends ObjectWriteBarrier {
    public static final NodeClass<G1ReferentFieldReadBarrier> TYPE = NodeClass.create(G1ReferentFieldReadBarrier.class);

    protected final boolean doLoad;

    public G1ReferentFieldReadBarrier(AddressNode address, ValueNode expectedObject, boolean doLoad) {
        super(TYPE, address, expectedObject, true);
        this.doLoad = doLoad;
    }

    public ValueNode getExpectedObject() {
        return getValue();
    }

    public boolean doLoad() {
        return doLoad;
    }
}