1 /*
2 * Copyright (c) 2013, 2018, 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 package org.graalvm.compiler.hotspot.test;
26
27 import static org.graalvm.compiler.hotspot.replacements.HotSpotReplacementsUtil.referentOffset;
28
29 import java.lang.ref.WeakReference;
30
31 import org.graalvm.compiler.api.replacements.Fold;
32 import org.graalvm.compiler.debug.DebugContext;
33 import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;
34 import org.graalvm.compiler.hotspot.GraalHotSpotVMConfigBase;
35 import org.graalvm.compiler.hotspot.gc.g1.G1PostWriteBarrier;
36 import org.graalvm.compiler.hotspot.gc.g1.G1PreWriteBarrier;
37 import org.graalvm.compiler.hotspot.gc.g1.G1ReferentFieldReadBarrier;
38 import org.graalvm.compiler.hotspot.gc.shared.SerialWriteBarrier;
39 import org.graalvm.compiler.hotspot.phases.WriteBarrierAdditionPhase;
40 import org.graalvm.compiler.nodes.StructuredGraph;
41 import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;
42 import org.graalvm.compiler.nodes.graphbuilderconf.InvocationPlugins;
43 import org.graalvm.compiler.nodes.graphbuilderconf.NodeIntrinsicPluginFactory;
44 import org.graalvm.compiler.nodes.memory.HeapAccess.BarrierType;
45 import org.graalvm.compiler.nodes.memory.ReadNode;
46 import org.graalvm.compiler.nodes.memory.WriteNode;
47 import org.graalvm.compiler.nodes.memory.address.OffsetAddressNode;
48 import org.graalvm.compiler.nodes.spi.LoweringTool;
49 import org.graalvm.compiler.phases.OptimisticOptimizations;
50 import org.graalvm.compiler.phases.common.CanonicalizerPhase;
51 import org.graalvm.compiler.phases.common.GuardLoweringPhase;
52 import org.graalvm.compiler.phases.common.LoweringPhase;
53 import org.graalvm.compiler.phases.common.inlining.InliningPhase;
54 import org.graalvm.compiler.phases.common.inlining.policy.InlineEverythingPolicy;
55 import org.graalvm.compiler.phases.tiers.HighTierContext;
56 import org.graalvm.compiler.phases.tiers.MidTierContext;
57 import org.graalvm.compiler.replacements.NodeIntrinsificationProvider;
58 import org.junit.Assert;
59 import org.junit.Test;
60
61 import jdk.vm.ci.hotspot.HotSpotInstalledCode;
62 import jdk.vm.ci.meta.JavaConstant;
63 import jdk.vm.ci.meta.ResolvedJavaMethod;
64 import sun.misc.Unsafe;
65
66 /**
67 * The following unit tests assert the presence of write barriers for both Serial and G1 GCs.
68 * Normally, the tests check for compile time inserted barriers. However, there are the cases of
69 * unsafe loads of the java.lang.ref.Reference.referent field where runtime checks have to be
70 * performed also. For those cases, the unit tests check the presence of the compile-time inserted
71 * barriers. Concerning the runtime checks, the results of variable inputs (object types and
72 * offsets) passed as input parameters can be checked against printed output from the G1 write
73 * barrier snippets. The runtime checks have been validated offline.
74 */
75 public class WriteBarrierAdditionTest extends HotSpotGraalCompilerTest {
76
77 private final GraalHotSpotVMConfig config = runtime().getVMConfig();
78
79 public static class Container {
80
81 public Container a;
82 public Container b;
83 }
84
85 /**
86 * Expected 2 barriers for the Serial GC and 4 for G1 (2 pre + 2 post).
87 */
88 @Test
89 public void test1() throws Exception {
90 testHelper("test1Snippet", (config.useG1GC) ? 4 : 2);
91 }
92
93 public static void test1Snippet() {
94 Container main = new Container();
95 Container temp1 = new Container();
96 Container temp2 = new Container();
97 main.a = temp1;
98 main.b = temp2;
99 }
100
101 /**
102 * Expected 4 barriers for the Serial GC and 8 for G1 (4 pre + 4 post).
103 */
104 @Test
105 public void test2() throws Exception {
106 testHelper("test2Snippet", config.useG1GC ? 8 : 4);
107 }
108
109 public static void test2Snippet(boolean test) {
110 Container main = new Container();
111 Container temp1 = new Container();
112 Container temp2 = new Container();
113 for (int i = 0; i < 10; i++) {
114 if (test) {
115 main.a = temp1;
116 main.b = temp2;
117 } else {
118 main.a = temp2;
119 main.b = temp1;
120 }
121 }
122 }
123
124 /**
125 * Expected 4 barriers for the Serial GC and 8 for G1 (4 pre + 4 post).
126 */
127 @Test
128 public void test3() throws Exception {
129 testHelper("test3Snippet", config.useG1GC ? 8 : 4);
130 }
131
132 public static void test3Snippet() {
133 Container[] main = new Container[10];
134 Container temp1 = new Container();
135 Container temp2 = new Container();
136 for (int i = 0; i < 10; i++) {
137 main[i].a = main[i].b = temp1;
138 }
139
140 for (int i = 0; i < 10; i++) {
141 main[i].a = main[i].b = temp2;
142 }
143 }
144
145 /**
146 * Expected 2 barriers for the Serial GC and 5 for G1 (3 pre + 2 post) The (2 or 4) barriers are
147 * emitted while initializing the fields of the WeakReference instance. The extra pre barrier of
148 * G1 concerns the read of the referent field.
149 */
150 @Test
151 public void test4() throws Exception {
152 testHelper("test4Snippet", config.useG1GC ? 5 : 2);
153 }
154
155 public static Object test4Snippet() {
156 WeakReference<Object> weakRef = new WeakReference<>(new Object());
157 return weakRef.get();
158 }
159
160 static WeakReference<Object> wr = new WeakReference<>(new Object());
161 static Container con = new Container();
162
163 /**
164 * Expected 4 barriers for the Serial GC and 9 for G1 (1 ref + 4 pre + 4 post). In this test, we
165 * load the correct offset of the WeakReference object so naturally we assert the presence of
166 * the pre barrier.
167 */
168 @Test
169 public void test5() throws Exception {
170 testHelper("test5Snippet", config.useG1GC ? 1 : 0);
171 }
172
173 @Override
174 protected void registerInvocationPlugins(InvocationPlugins invocationPlugins) {
175 NodeIntrinsicPluginFactory.InjectionProvider injection = new NodeIntrinsificationProvider(getMetaAccess(), getSnippetReflection(), getProviders().getForeignCalls(), null);
176 new PluginFactory_WriteBarrierAdditionTest().registerPlugins(invocationPlugins, injection);
177 super.registerInvocationPlugins(invocationPlugins);
178 }
179
180 @Fold
181 public static boolean useCompressedOops(@Fold.InjectedParameter GraalHotSpotVMConfig config) {
182 return config.useCompressedOops;
183 }
184
185 public static Object test5Snippet() throws Exception {
186 return UNSAFE.getObject(wr, useCompressedOops(GraalHotSpotVMConfigBase.INJECTED_VMCONFIG) ? 12L : 16L);
187 }
188
189 /**
190 * The following test concerns the runtime checks of the unsafe loads. In this test, we unsafely
191 * load the java.lang.ref.Reference.referent field so the pre barier has to be executed.
192 */
193 @Test
194 public void test6() throws Exception {
195 test2("testUnsafeLoad", UNSAFE, wr, Long.valueOf(referentOffset(getMetaAccess())), null);
196 }
197
198 /**
199 * The following test concerns the runtime checks of the unsafe loads. In this test, we unsafely
200 * load a matching offset of a wrong object so the pre barier must not be executed.
201 */
202 @Test
203 public void test7() throws Exception {
204 test2("testUnsafeLoad", UNSAFE, con, Long.valueOf(referentOffset(getMetaAccess())), null);
205 }
206
207 /**
208 * The following test concerns the runtime checks of the unsafe loads. In this test, we unsafely
209 * load a non-matching offset field of the java.lang.ref.Reference object so the pre barier must
210 * not be executed.
211 */
212 @Test
213 public void test8() throws Exception {
214 test2("testUnsafeLoad", UNSAFE, wr, Long.valueOf(config.useCompressedOops ? 20 : 32), null);
215 }
216
217 /**
218 * The following test concerns the runtime checks of the unsafe loads. In this test, we unsafely
219 * load a matching offset+disp field of the java.lang.ref.Reference object so the pre barier
220 * must be executed.
221 */
222 @Test
223 public void test10() throws Exception {
224 test2("testUnsafeLoad", UNSAFE, wr, Long.valueOf(config.useCompressedOops ? 6 : 8), Integer.valueOf(config.useCompressedOops ? 6 : 8));
225 }
226
227 /**
228 * The following test concerns the runtime checks of the unsafe loads. In this test, we unsafely
229 * load a non-matching offset+disp field of the java.lang.ref.Reference object so the pre barier
230 * must not be executed.
231 */
232 @Test
233 public void test9() throws Exception {
234 test2("testUnsafeLoad", UNSAFE, wr, Long.valueOf(config.useCompressedOops ? 10 : 16), Integer.valueOf(config.useCompressedOops ? 10 : 16));
235 }
236
237 static Object[] src = new Object[1];
238 static Object[] dst = new Object[1];
239
240 static {
241 for (int i = 0; i < src.length; i++) {
242 src[i] = new Object();
243 }
244 for (int i = 0; i < dst.length; i++) {
245 dst[i] = new Object();
246 }
247 }
248
249 public static void testArrayCopy(Object a, Object b, Object c) throws Exception {
250 System.arraycopy(a, 0, b, 0, (int) c);
251 }
252
253 @Test
254 public void test11() throws Exception {
255 test2("testArrayCopy", src, dst, dst.length);
256 }
257
258 public static Object testUnsafeLoad(Unsafe theUnsafe, Object a, Object b, Object c) throws Exception {
259 final int offset = (c == null ? 0 : ((Integer) c).intValue());
260 final long displacement = (b == null ? 0 : ((Long) b).longValue());
261 return theUnsafe.getObject(a, offset + displacement);
262 }
263
264 private HotSpotInstalledCode getInstalledCode(String name, boolean withUnsafePrefix) throws Exception {
265 final ResolvedJavaMethod javaMethod = withUnsafePrefix ? getResolvedJavaMethod(WriteBarrierAdditionTest.class, name, Unsafe.class, Object.class, Object.class, Object.class)
266 : getResolvedJavaMethod(WriteBarrierAdditionTest.class, name, Object.class, Object.class, Object.class);
267 final HotSpotInstalledCode installedCode = (HotSpotInstalledCode) getCode(javaMethod);
268 return installedCode;
269 }
270
271 @SuppressWarnings("try")
272 private void testHelper(final String snippetName, final int expectedBarriers) throws Exception, SecurityException {
273 ResolvedJavaMethod snippet = getResolvedJavaMethod(snippetName);
274 DebugContext debug = getDebugContext();
275 try (DebugContext.Scope s = debug.scope("WriteBarrierAdditionTest", snippet)) {
276 StructuredGraph graph = parseEager(snippet, AllowAssumptions.NO, debug);
277 HighTierContext highContext = getDefaultHighTierContext();
278 MidTierContext midContext = new MidTierContext(getProviders(), getTargetProvider(), OptimisticOptimizations.ALL, graph.getProfilingInfo());
279 new InliningPhase(new InlineEverythingPolicy(), new CanonicalizerPhase()).apply(graph, highContext);
280 new CanonicalizerPhase().apply(graph, highContext);
281 new LoweringPhase(new CanonicalizerPhase(), LoweringTool.StandardLoweringStage.HIGH_TIER).apply(graph, highContext);
282 new GuardLoweringPhase().apply(graph, midContext);
283 new LoweringPhase(new CanonicalizerPhase(), LoweringTool.StandardLoweringStage.MID_TIER).apply(graph, midContext);
284 new WriteBarrierAdditionPhase(config).apply(graph);
285 debug.dump(DebugContext.BASIC_LEVEL, graph, "After Write Barrier Addition");
286
287 int barriers = 0;
288 if (config.useG1GC) {
289 barriers = graph.getNodes().filter(G1ReferentFieldReadBarrier.class).count() + graph.getNodes().filter(G1PreWriteBarrier.class).count() +
290 graph.getNodes().filter(G1PostWriteBarrier.class).count();
291 } else if (config.useEpsilonGC) {
292 barriers = expectedBarriers;
293 } else {
294 barriers = graph.getNodes().filter(SerialWriteBarrier.class).count();
295 }
296 if (expectedBarriers != barriers) {
297 Assert.assertEquals(getScheduledGraphString(graph), expectedBarriers, barriers);
298 }
299 for (WriteNode write : graph.getNodes().filter(WriteNode.class)) {
300 if (config.useG1GC) {
301 if (write.getBarrierType() != BarrierType.NONE) {
302 Assert.assertEquals(1, write.successors().count());
303 Assert.assertTrue(write.next() instanceof G1PostWriteBarrier);
304 Assert.assertTrue(write.predecessor() instanceof G1PreWriteBarrier);
305 }
306 } else if (config.useEpsilonGC) {
307 if (write.getBarrierType() != BarrierType.NONE && write.successors().count() > 0) {
308 // Membar can follow, so check there are no barriers from other collectors only
309 Assert.assertFalse(write.next() instanceof G1PostWriteBarrier);
310 Assert.assertFalse(write.next() instanceof SerialWriteBarrier);
311 }
312 } else {
313 if (write.getBarrierType() != BarrierType.NONE) {
314 Assert.assertEquals(1, write.successors().count());
315 Assert.assertTrue(write.next() instanceof SerialWriteBarrier);
316 }
317 }
318 }
319
320 for (ReadNode read : graph.getNodes().filter(ReadNode.class)) {
321 if (read.getBarrierType() != BarrierType.NONE) {
322 Assert.assertTrue(read.getAddress() instanceof OffsetAddressNode);
323 JavaConstant constDisp = ((OffsetAddressNode) read.getAddress()).getOffset().asJavaConstant();
324 Assert.assertNotNull(constDisp);
325 Assert.assertEquals(referentOffset(getMetaAccess()), constDisp.asLong());
326 Assert.assertTrue(config.useG1GC);
327 Assert.assertEquals(BarrierType.PRECISE, read.getBarrierType());
328 Assert.assertTrue(read.next() instanceof G1ReferentFieldReadBarrier);
329 }
330 }
331 } catch (Throwable e) {
332 throw debug.handle(e);
333 }
334 }
335
336 private void test2(final String snippet, Object... args) throws Exception {
337 HotSpotInstalledCode code = getInstalledCode(snippet, args[0] instanceof Unsafe);
338 code.executeVarargs(args);
339 }
340 }