1 /*
   2  * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2019, Red Hat Inc. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
  22  * questions.
  23  */
  24 
  25 
  26 package org.graalvm.compiler.hotspot.gc.shared;
  27 
  28 import org.graalvm.compiler.debug.GraalError;
  29 import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;
  30 import org.graalvm.compiler.nodes.StructuredGraph;
  31 import org.graalvm.compiler.nodes.ValueNode;
  32 import org.graalvm.compiler.nodes.extended.ArrayRangeWrite;
  33 import org.graalvm.compiler.nodes.java.AbstractCompareAndSwapNode;
  34 import org.graalvm.compiler.nodes.java.LoweredAtomicReadAndWriteNode;
  35 import org.graalvm.compiler.nodes.memory.FixedAccessNode;
  36 import org.graalvm.compiler.nodes.memory.HeapAccess;
  37 import org.graalvm.compiler.nodes.memory.ReadNode;
  38 import org.graalvm.compiler.nodes.memory.WriteNode;
  39 import org.graalvm.compiler.nodes.memory.address.AddressNode;
  40 import org.graalvm.compiler.nodes.type.StampTool;
  41 
  42 public class CardTableBarrierSet extends BarrierSet {
  43 
  44     public CardTableBarrierSet(GraalHotSpotVMConfig vmConfig) {
  45         super(vmConfig);
  46     }
  47 
  48     @Override
  49     public void addReadNodeBarriers(ReadNode node, StructuredGraph graph) {
  50         // Nothing to do here.
  51     }
  52 
  53     @Override
  54     public void addWriteNodeBarriers(WriteNode node, StructuredGraph graph) {
  55         HeapAccess.BarrierType barrierType = node.getBarrierType();
  56         switch (barrierType) {
  57             case NONE:
  58                 // nothing to do
  59                 break;
  60             case FIELD:
  61             case ARRAY:
  62             case UNKNOWN:
  63                 boolean precise = barrierType != HeapAccess.BarrierType.FIELD;
  64                 boolean init = node.getLocationIdentity().isInit();
  65                 if (!init || !getVMConfig().useDeferredInitBarriers) {
  66                     addSerialPostWriteBarrier(node, node.getAddress(), node.value(), precise, graph);
  67                 }
  68                 break;
  69             default:
  70                 throw new GraalError("unexpected barrier type: " + barrierType);
  71         }
  72     }
  73 
  74     @Override
  75     public void addAtomicReadWriteNodeBarriers(LoweredAtomicReadAndWriteNode node, StructuredGraph graph) {
  76         HeapAccess.BarrierType barrierType = node.getBarrierType();
  77         switch (barrierType) {
  78             case NONE:
  79                 // nothing to do
  80                 break;
  81             case FIELD:
  82             case ARRAY:
  83             case UNKNOWN:
  84                 boolean precise = barrierType != HeapAccess.BarrierType.FIELD;
  85                 addSerialPostWriteBarrier(node, node.getAddress(), node.getNewValue(), precise, graph);
  86                 break;
  87             default:
  88                 throw new GraalError("unexpected barrier type: " + barrierType);
  89         }
  90     }
  91 
  92     @Override
  93     public void addCASBarriers(AbstractCompareAndSwapNode node, StructuredGraph graph) {
  94         HeapAccess.BarrierType barrierType = node.getBarrierType();
  95         switch (barrierType) {
  96             case NONE:
  97                 // nothing to do
  98                 break;
  99             case FIELD:
 100             case ARRAY:
 101             case UNKNOWN:
 102                 boolean precise = barrierType != HeapAccess.BarrierType.FIELD;
 103                 addSerialPostWriteBarrier(node, node.getAddress(), node.getNewValue(), precise, graph);
 104                 break;
 105             default:
 106                 throw new GraalError("unexpected barrier type: " + barrierType);
 107         }
 108     }
 109 
 110     @Override
 111     public void addArrayRangeBarriers(ArrayRangeWrite write, StructuredGraph graph) {
 112         SerialArrayRangeWriteBarrier serialArrayRangeWriteBarrier = graph.add(new SerialArrayRangeWriteBarrier(write.getAddress(), write.getLength(), write.getElementStride()));
 113         graph.addAfterFixed(write.asNode(), serialArrayRangeWriteBarrier);
 114     }
 115 
 116     protected void addSerialPostWriteBarrier(FixedAccessNode node, AddressNode address, ValueNode value, boolean precise, StructuredGraph graph) {
 117         final boolean alwaysNull = StampTool.isPointerAlwaysNull(value);
 118         if (alwaysNull) {
 119             // Serial barrier isn't needed for null value
 120             return;
 121         }
 122         graph.addAfterFixed(node, graph.add(new SerialWriteBarrier(address, precise)));
 123     }
 124 }