1 /*
2 * Copyright (c) 2014, 2015, 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 * @library /test/lib /
28 * @modules java.base/jdk.internal.org.objectweb.asm
29 * java.base/jdk.internal.misc
30 * java.compiler
31 * java.management
32 * jdk.jvmstat/sun.jvmstat.monitor
33 *
34 * @build sun.hotspot.WhiteBox
35 * @run driver ClassFileInstaller sun.hotspot.WhiteBox
36 * sun.hotspot.WhiteBox$WhiteBoxPermission
37 * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
38 * -XX:+WhiteBoxAPI -XX:+LogCompilation
39 * -XX:CompileCommand=compileonly,UnstableIfExecutable.test
40 * -XX:LogFile=always_taken_not_fired.xml
41 * compiler.uncommontrap.TestUnstableIfTrap ALWAYS_TAKEN false
42 * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
43 * -XX:+WhiteBoxAPI -XX:+LogCompilation
44 * -XX:CompileCommand=compileonly,UnstableIfExecutable.test
45 * -XX:LogFile=always_taken_fired.xml
46 * compiler.uncommontrap.TestUnstableIfTrap ALWAYS_TAKEN true
47 * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
48 * -XX:+WhiteBoxAPI -XX:+LogCompilation
49 * -XX:CompileCommand=compileonly,UnstableIfExecutable.test
50 * -XX:LogFile=never_taken_not_fired.xml
51 * compiler.uncommontrap.TestUnstableIfTrap NEVER_TAKEN false
52 * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
53 * -XX:+WhiteBoxAPI -XX:+LogCompilation
54 * -XX:CompileCommand=compileonly,UnstableIfExecutable.test
55 * -XX:LogFile=never_taken_fired.xml
56 * compiler.uncommontrap.TestUnstableIfTrap NEVER_TAKEN true
57 * @run driver compiler.testlibrary.uncommontrap.Verifier always_taken_not_fired.xml
58 * always_taken_fired.xml
59 * never_taken_not_fired.xml
60 * never_taken_fired.xml
61 */
62
63 package compiler.uncommontrap;
64
65 import compiler.testlibrary.uncommontrap.Verifier;
66 import jdk.internal.org.objectweb.asm.ClassVisitor;
67 import jdk.internal.org.objectweb.asm.ClassWriter;
68 import jdk.internal.org.objectweb.asm.Label;
69 import jdk.internal.org.objectweb.asm.MethodVisitor;
70 import jdk.test.lib.ByteCodeLoader;
71 import jdk.test.lib.Platform;
72 import sun.hotspot.WhiteBox;
73
74 import java.io.File;
75 import java.io.FileWriter;
76 import java.io.IOException;
77 import java.lang.reflect.Method;
78 import java.util.Properties;
79
80 import static jdk.internal.org.objectweb.asm.Opcodes.ACC_ABSTRACT;
81 import static jdk.internal.org.objectweb.asm.Opcodes.ACC_PUBLIC;
82 import static jdk.internal.org.objectweb.asm.Opcodes.ACC_STATIC;
83 import static jdk.internal.org.objectweb.asm.Opcodes.ACC_VOLATILE;
84 import static jdk.internal.org.objectweb.asm.Opcodes.GETSTATIC;
85 import static jdk.internal.org.objectweb.asm.Opcodes.GOTO;
86 import static jdk.internal.org.objectweb.asm.Opcodes.IADD;
87 import static jdk.internal.org.objectweb.asm.Opcodes.ICONST_1;
88 import static jdk.internal.org.objectweb.asm.Opcodes.IFEQ;
89 import static jdk.internal.org.objectweb.asm.Opcodes.ILOAD;
90 import static jdk.internal.org.objectweb.asm.Opcodes.ISUB;
91 import static jdk.internal.org.objectweb.asm.Opcodes.RETURN;
92
93 public class TestUnstableIfTrap {
94 private static final WhiteBox WB = WhiteBox.getWhiteBox();
95 private static final String CLASS_NAME = "UnstableIfExecutable";
96 private static final String METHOD_NAME = "test";
97 private static final String FIELD_NAME = "field";
98 private static final int ITERATIONS = 1_000_000;
99 // There is no dependency on particular class file version, so it could be
100 // set to any version (if you're updating this test for Java 42).
101 private static final int CLASS_FILE_VERSION = 49;
102 private static final int MAX_TIER = 4;
103 // This test aimed to verify that uncommon trap with reason "unstable_if"
104 // is emitted when method that contain control-flow divergence such that
105 // one of two branches is never taken (and other one is taken always).
106 // C2 will made a decision whether or not the branch was ever taken
107 // depending on method's profile.
108 // If profile was collected for a few method's invocations, then C2 will not
109 // trust in branches' probabilities and the tested trap won't be emitted.
110 // In fact, a method has to be invoked at least 40 time at the day when this
111 // comment was written (see Parse::dynamic_branch_prediction for an actual
112 // value). It would be to implementation dependent to use "40" as
113 // a threshold value in the test, so in order to improve test's robustness
114 // the threshold value is 1000: if the tested method was compiled by C2
115 // before it was invoked 1000 times, then we won't verify that trap was
116 // emitted and fired.
117 private static final int MIN_INVOCATIONS_BEFORE_C2_COMPILATION = 1000;
118 /**
119 * Description of test case parameters and uncommon trap that will
120 * be emitted during tested method compilation.
121 */
122 private static enum TestCaseName {
123 ALWAYS_TAKEN(false, "taken always"),
124 NEVER_TAKEN(true, "taken never");
125 TestCaseName(boolean predicate, String comment) {
126 this.predicate = predicate;
127 this.comment = comment;
128 }
129
130 public final boolean predicate;
131 public final String name = "unstable_if";
132 public final String comment;
133 }
134
135 public static void main(String args[]) {
136 if (args.length != 2) {
137 throw new Error("Expected two arguments: test case name and a "
138 + "boolean determining if uncommon trap should be fired.");
139 }
140 test(TestCaseName.valueOf(args[0]), Boolean.valueOf(args[1]));
141 }
142
143 private static void test(TestCaseName testCase, boolean shouldBeFired) {
144 Method testMethod;
145 Label unstableIfLocation = new Label();
146 boolean shouldBeEmitted;
147 boolean compiledToEarly = false;
148
149 try {
150 Class testClass = ByteCodeLoader.load(CLASS_NAME,
151 generateTest(unstableIfLocation));
152 testMethod = testClass.getDeclaredMethod(METHOD_NAME,
153 boolean.class);
154 for (int i = 0; i < ITERATIONS; i++) {
155 testMethod.invoke(null, testCase.predicate);
156 if (i < MIN_INVOCATIONS_BEFORE_C2_COMPILATION
157 && isMethodCompiledByC2(testMethod)) {
158 compiledToEarly = true;
159 // There is no sense in further invocations: we already
160 // decided to avoid verification.
161 break;
162 }
163 }
164 // We're checking that trap should be emitted (i.e. it was compiled
165 // by C2) before the trap is fired, because otherwise the nmethod
166 // will be deoptimized and isMethodCompiledByC2 will return false.
167 shouldBeEmitted = isMethodCompiledByC2(testMethod)
168 && !compiledToEarly;
169 if (shouldBeFired) {
170 testMethod.invoke(null, !testCase.predicate);
171 }
172 } catch (ReflectiveOperationException e) {
173 throw new Error("Test case should be generated, loaded and executed"
174 + " without any issues.", e);
175 }
176
177 shouldBeFired &= shouldBeEmitted;
178
179 Properties properties = new Properties();
180 properties.setProperty(Verifier.VERIFICATION_SHOULD_BE_SKIPPED,
181 Boolean.toString(compiledToEarly));
182 properties.setProperty(Verifier.UNCOMMON_TRAP_SHOULD_EMITTED,
183 Boolean.toString(shouldBeEmitted));
184 properties.setProperty(Verifier.UNCOMMON_TRAP_SHOULD_FIRED,
185 Boolean.toString(shouldBeFired));
186 properties.setProperty(Verifier.UNCOMMON_TRAP_NAME, testCase.name);
187 properties.setProperty(Verifier.UNCOMMON_TRAP_COMMENT,
188 testCase.comment);
189 properties.setProperty(Verifier.UNCOMMON_TRAP_BCI,
190 Integer.toString(unstableIfLocation.getOffset()));
191
192 properties.list(System.out);
193
194 File f = new File(WB.getStringVMFlag("LogFile") +
195 Verifier.PROPERTIES_FILE_SUFFIX);
196 try (FileWriter wr = new FileWriter(f)) {
197 properties.store(wr, "");
198 } catch (IOException e) {
199 throw new Error("Unable to store test properties.", e);
200 }
201 }
202
203 private static boolean isMethodCompiledByC2(Method m) {
204 boolean isTiered = WB.getBooleanVMFlag("TieredCompilation");
205 boolean isMethodCompiled = WB.isMethodCompiled(m);
206 boolean isMethodCompiledAtMaxTier
207 = WB.getMethodCompilationLevel(m) == MAX_TIER;
208
209 return Platform.isServer() && isMethodCompiled
210 && (!isTiered || isMethodCompiledAtMaxTier);
211 }
212
213 /**
214 * Generates class with name {@code CLASS_NAME}, which will contain a
215 * static method {@code METHOD_NAME}:
216 *
217 * <pre>{@code
218 * public abstract class UnstableIfExecutable {
219 * private static int field = 0;
220 *
221 * public static void test(boolean alwaysTrue) {
222 * if (alwaysTrue) {
223 * field++;
224 * } else {
225 * field--;
226 * }
227 * }
228 * }
229 * }</pre>
230 *
231 * @return generated bytecode.
232 */
233 private static byte[] generateTest(Label unstableIfLocation) {
234 ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
235
236 cw.visit(CLASS_FILE_VERSION, ACC_PUBLIC | ACC_ABSTRACT, CLASS_NAME,
237 null, "java/lang/Object", null);
238
239 cw.visitField(ACC_PUBLIC | ACC_STATIC | ACC_VOLATILE, FIELD_NAME,
240 "I", null, Integer.valueOf(0));
241
242 generateTestMethod(cw, unstableIfLocation);
243
244 return cw.toByteArray();
245 }
246
247 private static void generateTestMethod(ClassVisitor cv,
248 Label unstableIfLocation) {
249 MethodVisitor mv = cv.visitMethod(ACC_PUBLIC | ACC_STATIC, METHOD_NAME,
250 "(Z)V", null, null);
251 mv.visitCode();
252
253 Label end = new Label();
254 Label falseBranch = new Label();
255
256 // push "field" field's value and 1 to stack
257 mv.visitFieldInsn(GETSTATIC, CLASS_NAME, FIELD_NAME, "I");
258 mv.visitInsn(ICONST_1);
259 // load argument's value
260 mv.visitVarInsn(ILOAD, 0); // alwaysTrue
261 // here is our unstable if
262 mv.visitLabel(unstableIfLocation);
263 mv.visitJumpInsn(IFEQ, falseBranch);
264 // increment on "true"
265 mv.visitInsn(IADD);
266 mv.visitJumpInsn(GOTO, end);
267 // decrement on "false"
268 mv.visitLabel(falseBranch);
269 mv.visitInsn(ISUB);
270 mv.visitLabel(end);
271 // bye bye
272 mv.visitInsn(RETURN);
273
274 mv.visitMaxs(0, 0);
275 mv.visitEnd();
276 }
277 }
278