1 /*
2 * Copyright (c) 2014, 2017, 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 * @test
26 * @bug 8030976 8059226
27 * @requires !vm.graal.enabled
28 * @library /test/lib /
29 * @modules java.base/jdk.internal.org.objectweb.asm
30 * java.base/jdk.internal.misc
31 * java.compiler
32 * java.management
33 * jdk.internal.jvmstat/sun.jvmstat.monitor
34 *
35 * @build sun.hotspot.WhiteBox
36 * @run driver ClassFileInstaller sun.hotspot.WhiteBox
37 * sun.hotspot.WhiteBox$WhiteBoxPermission
38 * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
39 * -XX:+WhiteBoxAPI -XX:+LogCompilation
40 * -XX:CompileCommand=compileonly,UnstableIfExecutable.test
41 * -XX:LogFile=always_taken_not_fired.xml
42 * compiler.uncommontrap.TestUnstableIfTrap ALWAYS_TAKEN false
43 * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
44 * -XX:+WhiteBoxAPI -XX:+LogCompilation
45 * -XX:CompileCommand=compileonly,UnstableIfExecutable.test
46 * -XX:LogFile=always_taken_fired.xml
47 * compiler.uncommontrap.TestUnstableIfTrap ALWAYS_TAKEN true
48 * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
49 * -XX:+WhiteBoxAPI -XX:+LogCompilation
50 * -XX:CompileCommand=compileonly,UnstableIfExecutable.test
51 * -XX:LogFile=never_taken_not_fired.xml
52 * compiler.uncommontrap.TestUnstableIfTrap NEVER_TAKEN false
53 * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
54 * -XX:+WhiteBoxAPI -XX:+LogCompilation
55 * -XX:CompileCommand=compileonly,UnstableIfExecutable.test
56 * -XX:LogFile=never_taken_fired.xml
57 * compiler.uncommontrap.TestUnstableIfTrap NEVER_TAKEN true
58 * @run driver compiler.testlibrary.uncommontrap.Verifier always_taken_not_fired.xml
59 * always_taken_fired.xml
60 * never_taken_not_fired.xml
61 * never_taken_fired.xml
62 */
63
64 package compiler.uncommontrap;
65
66 import compiler.testlibrary.uncommontrap.Verifier;
67 import jdk.internal.org.objectweb.asm.ClassVisitor;
68 import jdk.internal.org.objectweb.asm.ClassWriter;
69 import jdk.internal.org.objectweb.asm.Label;
70 import jdk.internal.org.objectweb.asm.MethodVisitor;
71 import jdk.test.lib.ByteCodeLoader;
72 import jdk.test.lib.Platform;
73 import sun.hotspot.WhiteBox;
74
75 import java.io.File;
76 import java.io.FileWriter;
77 import java.io.IOException;
78 import java.lang.reflect.Method;
79 import java.util.Properties;
80
81 import static jdk.internal.org.objectweb.asm.Opcodes.ACC_ABSTRACT;
82 import static jdk.internal.org.objectweb.asm.Opcodes.ACC_PUBLIC;
83 import static jdk.internal.org.objectweb.asm.Opcodes.ACC_STATIC;
84 import static jdk.internal.org.objectweb.asm.Opcodes.ACC_VOLATILE;
85 import static jdk.internal.org.objectweb.asm.Opcodes.GETSTATIC;
86 import static jdk.internal.org.objectweb.asm.Opcodes.GOTO;
87 import static jdk.internal.org.objectweb.asm.Opcodes.IADD;
88 import static jdk.internal.org.objectweb.asm.Opcodes.ICONST_1;
89 import static jdk.internal.org.objectweb.asm.Opcodes.IFEQ;
90 import static jdk.internal.org.objectweb.asm.Opcodes.ILOAD;
91 import static jdk.internal.org.objectweb.asm.Opcodes.ISUB;
92 import static jdk.internal.org.objectweb.asm.Opcodes.RETURN;
93
94 public class TestUnstableIfTrap {
95 private static final WhiteBox WB = WhiteBox.getWhiteBox();
96 private static final String CLASS_NAME = "UnstableIfExecutable";
97 private static final String METHOD_NAME = "test";
98 private static final String FIELD_NAME = "field";
99 private static final int ITERATIONS = 1_000_000;
100 // There is no dependency on particular class file version, so it could be
101 // set to any version (if you're updating this test for Java 42).
102 private static final int CLASS_FILE_VERSION = 49;
103 private static final int MAX_TIER = 4;
104 // This test aimed to verify that uncommon trap with reason "unstable_if"
105 // is emitted when method that contain control-flow divergence such that
106 // one of two branches is never taken (and other one is taken always).
107 // C2 will made a decision whether or not the branch was ever taken
108 // depending on method's profile.
109 // If profile was collected for a few method's invocations, then C2 will not
110 // trust in branches' probabilities and the tested trap won't be emitted.
111 // In fact, a method has to be invoked at least 40 time at the day when this
112 // comment was written (see Parse::dynamic_branch_prediction for an actual
113 // value). It would be to implementation dependent to use "40" as
114 // a threshold value in the test, so in order to improve test's robustness
115 // the threshold value is 1000: if the tested method was compiled by C2
116 // before it was invoked 1000 times, then we won't verify that trap was
117 // emitted and fired.
118 private static final int MIN_INVOCATIONS_BEFORE_C2_COMPILATION = 1000;
119 /**
120 * Description of test case parameters and uncommon trap that will
121 * be emitted during tested method compilation.
122 */
123 private static enum TestCaseName {
124 ALWAYS_TAKEN(false, "taken always"),
125 NEVER_TAKEN(true, "taken never");
126 TestCaseName(boolean predicate, String comment) {
127 this.predicate = predicate;
128 this.comment = comment;
129 }
130
131 public final boolean predicate;
132 public final String name = "unstable_if";
133 public final String comment;
134 }
135
136 public static void main(String args[]) {
137 if (args.length != 2) {
138 throw new Error("Expected two arguments: test case name and a "
139 + "boolean determining if uncommon trap should be fired.");
140 }
141 test(TestCaseName.valueOf(args[0]), Boolean.valueOf(args[1]));
142 }
143
144 private static void test(TestCaseName testCase, boolean shouldBeFired) {
145 Method testMethod;
146 Label unstableIfLocation = new Label();
147 boolean shouldBeEmitted;
148 boolean compiledToEarly = false;
149
150 try {
151 Class testClass = ByteCodeLoader.load(CLASS_NAME,
152 generateTest(unstableIfLocation));
153 testMethod = testClass.getDeclaredMethod(METHOD_NAME,
154 boolean.class);
155 for (int i = 0; i < ITERATIONS; i++) {
156 testMethod.invoke(null, testCase.predicate);
157 if (i < MIN_INVOCATIONS_BEFORE_C2_COMPILATION
158 && isMethodCompiledByC2(testMethod)) {
159 compiledToEarly = true;
160 // There is no sense in further invocations: we already
161 // decided to avoid verification.
162 break;
163 }
164 }
165 // We're checking that trap should be emitted (i.e. it was compiled
166 // by C2) before the trap is fired, because otherwise the nmethod
167 // will be deoptimized and isMethodCompiledByC2 will return false.
168 shouldBeEmitted = isMethodCompiledByC2(testMethod)
169 && !compiledToEarly;
170 if (shouldBeFired) {
171 testMethod.invoke(null, !testCase.predicate);
172 }
173 } catch (ReflectiveOperationException e) {
174 throw new Error("Test case should be generated, loaded and executed"
175 + " without any issues.", e);
176 }
177
178 shouldBeFired &= shouldBeEmitted;
179
180 Properties properties = new Properties();
181 properties.setProperty(Verifier.VERIFICATION_SHOULD_BE_SKIPPED,
182 Boolean.toString(compiledToEarly));
183 properties.setProperty(Verifier.UNCOMMON_TRAP_SHOULD_EMITTED,
184 Boolean.toString(shouldBeEmitted));
185 properties.setProperty(Verifier.UNCOMMON_TRAP_SHOULD_FIRED,
186 Boolean.toString(shouldBeFired));
187 properties.setProperty(Verifier.UNCOMMON_TRAP_NAME, testCase.name);
188 properties.setProperty(Verifier.UNCOMMON_TRAP_COMMENT,
189 testCase.comment);
190 properties.setProperty(Verifier.UNCOMMON_TRAP_BCI,
191 Integer.toString(unstableIfLocation.getOffset()));
192
193 properties.list(System.out);
194
195 File f = new File(WB.getStringVMFlag("LogFile") +
196 Verifier.PROPERTIES_FILE_SUFFIX);
197 try (FileWriter wr = new FileWriter(f)) {
198 properties.store(wr, "");
199 } catch (IOException e) {
200 throw new Error("Unable to store test properties.", e);
201 }
202 }
203
204 private static boolean isMethodCompiledByC2(Method m) {
205 boolean isTiered = WB.getBooleanVMFlag("TieredCompilation");
206 boolean isMethodCompiled = WB.isMethodCompiled(m);
207 boolean isMethodCompiledAtMaxTier
208 = WB.getMethodCompilationLevel(m) == MAX_TIER;
209
210 return Platform.isServer() && !Platform.isEmulatedClient() && isMethodCompiled
211 && (!isTiered || isMethodCompiledAtMaxTier);
212 }
213
214 /**
215 * Generates class with name {@code CLASS_NAME}, which will contain a
216 * static method {@code METHOD_NAME}:
217 *
218 * <pre>{@code
219 * public abstract class UnstableIfExecutable {
220 * private static int field = 0;
221 *
222 * public static void test(boolean alwaysTrue) {
223 * if (alwaysTrue) {
224 * field++;
225 * } else {
226 * field--;
227 * }
228 * }
229 * }
230 * }</pre>
231 *
232 * @return generated bytecode.
233 */
234 private static byte[] generateTest(Label unstableIfLocation) {
235 ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
236
237 cw.visit(CLASS_FILE_VERSION, ACC_PUBLIC | ACC_ABSTRACT, CLASS_NAME,
238 null, "java/lang/Object", null);
239
240 cw.visitField(ACC_PUBLIC | ACC_STATIC | ACC_VOLATILE, FIELD_NAME,
241 "I", null, Integer.valueOf(0));
242
243 generateTestMethod(cw, unstableIfLocation);
244
245 return cw.toByteArray();
246 }
247
248 private static void generateTestMethod(ClassVisitor cv,
249 Label unstableIfLocation) {
250 MethodVisitor mv = cv.visitMethod(ACC_PUBLIC | ACC_STATIC, METHOD_NAME,
251 "(Z)V", null, null);
252 mv.visitCode();
253
254 Label end = new Label();
255 Label falseBranch = new Label();
256
257 // push "field" field's value and 1 to stack
258 mv.visitFieldInsn(GETSTATIC, CLASS_NAME, FIELD_NAME, "I");
259 mv.visitInsn(ICONST_1);
260 // load argument's value
261 mv.visitVarInsn(ILOAD, 0); // alwaysTrue
262 // here is our unstable if
263 mv.visitLabel(unstableIfLocation);
264 mv.visitJumpInsn(IFEQ, falseBranch);
265 // increment on "true"
266 mv.visitInsn(IADD);
267 mv.visitJumpInsn(GOTO, end);
268 // decrement on "false"
269 mv.visitLabel(falseBranch);
270 mv.visitInsn(ISUB);
271 mv.visitLabel(end);
272 // bye bye
273 mv.visitInsn(RETURN);
274
275 mv.visitMaxs(0, 0);
276 mv.visitEnd();
277 }
278 }
279