1 /*
   2  * Copyright (c) 2013, 2019, 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 
  24 
  25 
  26 package org.graalvm.compiler.hotspot.gc.g1;
  27 
  28 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_64;
  29 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_64;
  30 
  31 import org.graalvm.compiler.graph.NodeClass;
  32 import org.graalvm.compiler.hotspot.gc.shared.ObjectWriteBarrier;
  33 import org.graalvm.compiler.nodeinfo.InputType;
  34 import org.graalvm.compiler.nodeinfo.NodeInfo;
  35 import org.graalvm.compiler.nodes.DeoptimizingNode;
  36 import org.graalvm.compiler.nodes.FrameState;
  37 import org.graalvm.compiler.nodes.ValueNode;
  38 import org.graalvm.compiler.nodes.memory.address.AddressNode;
  39 
  40 @NodeInfo(cycles = CYCLES_64, size = SIZE_64)
  41 public final class G1PreWriteBarrier extends ObjectWriteBarrier implements DeoptimizingNode.DeoptBefore {
  42 
  43     public static final NodeClass<G1PreWriteBarrier> TYPE = NodeClass.create(G1PreWriteBarrier.class);
  44 
  45     @OptionalInput(InputType.State) private FrameState stateBefore;
  46     private final boolean nullCheck;
  47     private final boolean doLoad;
  48 
  49     public G1PreWriteBarrier(AddressNode address, ValueNode expectedObject, boolean doLoad, boolean nullCheck) {
  50         super(TYPE, address, expectedObject, true);
  51         this.doLoad = doLoad;
  52         this.nullCheck = nullCheck;
  53     }
  54 
  55     public ValueNode getExpectedObject() {
  56         return getValue();
  57     }
  58 
  59     public boolean doLoad() {
  60         return doLoad;
  61     }
  62 
  63     public boolean getNullCheck() {
  64         return nullCheck;
  65     }
  66 
  67     @Override
  68     public boolean canDeoptimize() {
  69         return nullCheck;
  70     }
  71 
  72     @Override
  73     public FrameState stateBefore() {
  74         return stateBefore;
  75     }
  76 
  77     @Override
  78     public void setStateBefore(FrameState state) {
  79         updateUsages(stateBefore, state);
  80         stateBefore = state;
  81     }
  82 }