1 /*
   2  * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package org.graalvm.compiler.nodes.java;
  24 
  25 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_20;
  26 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_2;
  27 import static jdk.vm.ci.code.MemoryBarriers.LOAD_STORE;
  28 import static jdk.vm.ci.code.MemoryBarriers.STORE_STORE;
  29 
  30 import org.graalvm.compiler.core.common.type.StampFactory;
  31 import org.graalvm.compiler.graph.NodeClass;
  32 import org.graalvm.compiler.nodeinfo.NodeInfo;
  33 import org.graalvm.compiler.nodes.FixedWithNextNode;
  34 import org.graalvm.compiler.nodes.ValueNode;
  35 import org.graalvm.compiler.nodes.extended.MembarNode;
  36 import org.graalvm.compiler.nodes.spi.Lowerable;
  37 import org.graalvm.compiler.nodes.spi.LoweringTool;
  38 import org.graalvm.compiler.nodes.spi.Virtualizable;
  39 import org.graalvm.compiler.nodes.spi.VirtualizerTool;
  40 import org.graalvm.compiler.nodes.virtual.VirtualObjectNode;
  41 
  42 @NodeInfo(cycles = CYCLES_20, size = SIZE_2)
  43 public class FinalFieldBarrierNode extends FixedWithNextNode implements Virtualizable, Lowerable {
  44     public static final NodeClass<FinalFieldBarrierNode> TYPE = NodeClass.create(FinalFieldBarrierNode.class);
  45 
  46     @OptionalInput private ValueNode value;
  47 
  48     public FinalFieldBarrierNode(ValueNode value) {
  49         super(TYPE, StampFactory.forVoid());
  50         this.value = value;
  51     }
  52 
  53     public ValueNode getValue() {
  54         return value;
  55     }
  56 
  57     @Override
  58     public void virtualize(VirtualizerTool tool) {
  59         if (value != null && tool.getAlias(value) instanceof VirtualObjectNode) {
  60             tool.delete();
  61         }
  62     }
  63 
  64     @Override
  65     public void lower(LoweringTool tool) {
  66         graph().replaceFixedWithFixed(this, graph().add(new MembarNode(LOAD_STORE | STORE_STORE)));
  67     }
  68 }