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.g1;
27
28 import org.graalvm.compiler.debug.GraalError;
29 import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;
30 import org.graalvm.compiler.hotspot.gc.shared.BarrierSet;
31 import org.graalvm.compiler.nodes.StructuredGraph;
32 import org.graalvm.compiler.nodes.ValueNode;
33 import org.graalvm.compiler.nodes.extended.ArrayRangeWrite;
34 import org.graalvm.compiler.nodes.java.AbstractCompareAndSwapNode;
35 import org.graalvm.compiler.nodes.java.LoweredAtomicReadAndWriteNode;
36 import org.graalvm.compiler.nodes.memory.FixedAccessNode;
37 import org.graalvm.compiler.nodes.memory.HeapAccess;
38 import org.graalvm.compiler.nodes.memory.ReadNode;
39 import org.graalvm.compiler.nodes.memory.WriteNode;
40 import org.graalvm.compiler.nodes.memory.address.AddressNode;
41 import org.graalvm.compiler.nodes.type.StampTool;
42
43 public class G1BarrierSet extends BarrierSet {
44
45 public G1BarrierSet(GraalHotSpotVMConfig vmConfig) {
46 super(vmConfig);
47 }
48
49 @Override
50 public void addReadNodeBarriers(ReadNode node, StructuredGraph graph) {
51 if (node.getBarrierType() == HeapAccess.BarrierType.WEAK_FIELD) {
52 G1ReferentFieldReadBarrier barrier = graph.add(new G1ReferentFieldReadBarrier(node.getAddress(), node, false));
53 graph.addAfterFixed(node, barrier);
54 }
55 }
56
57 @Override
58 public void addWriteNodeBarriers(WriteNode node, StructuredGraph graph) {
59 HeapAccess.BarrierType barrierType = node.getBarrierType();
60 switch (barrierType) {
61 case NONE:
62 // nothing to do
63 break;
64 case FIELD:
65 case ARRAY:
66 case UNKNOWN:
67 boolean init = node.getLocationIdentity().isInit();
68 if (!init || !getVMConfig().useDeferredInitBarriers) {
69 if (!init) {
70 // The pre barrier does nothing if the value being read is null, so it can
71 // be explicitly skipped when this is an initializing store.
72 addG1PreWriteBarrier(node, node.getAddress(), null, true, node.getNullCheck(), graph);
73 }
74 boolean precise = barrierType != HeapAccess.BarrierType.FIELD;
75 addG1PostWriteBarrier(node, node.getAddress(), node.value(), precise, graph);
76 }
77 break;
78 default:
79 throw new GraalError("unexpected barrier type: " + barrierType);
80 }
81 }
82
83 @Override
84 public void addAtomicReadWriteNodeBarriers(LoweredAtomicReadAndWriteNode node, StructuredGraph graph) {
85 HeapAccess.BarrierType barrierType = node.getBarrierType();
86 switch (barrierType) {
87 case NONE:
88 // nothing to do
89 break;
90 case FIELD:
91 case ARRAY:
92 case UNKNOWN:
93 boolean precise = barrierType != HeapAccess.BarrierType.FIELD;
94 addG1PreWriteBarrier(node, node.getAddress(), null, true, node.getNullCheck(), graph);
95 addG1PostWriteBarrier(node, node.getAddress(), node.getNewValue(), precise, graph);
96 break;
97 default:
98 throw new GraalError("unexpected barrier type: " + barrierType);
99 }
100 }
101
102 @Override
103 public void addCASBarriers(AbstractCompareAndSwapNode node, StructuredGraph graph) {
104 HeapAccess.BarrierType barrierType = node.getBarrierType();
105 switch (barrierType) {
106 case NONE:
107 // nothing to do
108 break;
109 case FIELD:
110 case ARRAY:
111 case UNKNOWN:
112 boolean precise = barrierType != HeapAccess.BarrierType.FIELD;
113 addG1PreWriteBarrier(node, node.getAddress(), node.getExpectedValue(), false, false, graph);
114 addG1PostWriteBarrier(node, node.getAddress(), node.getNewValue(), precise, graph);
115 break;
116 default:
117 throw new GraalError("unexpected barrier type: " + barrierType);
118 }
119 }
120
121 @Override
122 public void addArrayRangeBarriers(ArrayRangeWrite write, StructuredGraph graph) {
123 if (!write.isInitialization()) {
124 // The pre barrier does nothing if the value being read is null, so it can
125 // be explicitly skipped when this is an initializing store.
126 G1ArrayRangePreWriteBarrier g1ArrayRangePreWriteBarrier = graph.add(new G1ArrayRangePreWriteBarrier(write.getAddress(), write.getLength(), write.getElementStride()));
127 graph.addBeforeFixed(write.asNode(), g1ArrayRangePreWriteBarrier);
128 }
129 G1ArrayRangePostWriteBarrier g1ArrayRangePostWriteBarrier = graph.add(new G1ArrayRangePostWriteBarrier(write.getAddress(), write.getLength(), write.getElementStride()));
130 graph.addAfterFixed(write.asNode(), g1ArrayRangePostWriteBarrier);
131 }
132
133 private static void addG1PreWriteBarrier(FixedAccessNode node, AddressNode address, ValueNode value, boolean doLoad, boolean nullCheck, StructuredGraph graph) {
134 G1PreWriteBarrier preBarrier = graph.add(new G1PreWriteBarrier(address, value, doLoad, nullCheck));
135 preBarrier.setStateBefore(node.stateBefore());
136 node.setNullCheck(false);
137 node.setStateBefore(null);
138 graph.addBeforeFixed(node, preBarrier);
139 }
140
141 private static void addG1PostWriteBarrier(FixedAccessNode node, AddressNode address, ValueNode value, boolean precise, StructuredGraph graph) {
142 final boolean alwaysNull = StampTool.isPointerAlwaysNull(value);
143 graph.addAfterFixed(node, graph.add(new G1PostWriteBarrier(address, value, precise, alwaysNull)));
144 }
145 }