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 }