8059342: Add test to cover JDK-8030976

Reviewed-by: kvn, iignatyev

hotspot/test/compiler/testlibrary/uncommontrap/Verifier.java

+/*
+ * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package uncommontrap;
+
+import java.io.FileReader;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Properties;
+import java.util.regex.Pattern;
+
+import com.oracle.java.testlibrary.Asserts;
+/**
+ * Utility tool aimed to verify presence or absence of specified uncommon trap
+ * in compilation log.
+ */
+public class Verifier {
+    public static final String PROPERTIES_FILE_SUFFIX = ".verify.properties";
+    public static final String VERIFICATION_SHOULD_BE_SKIPPED
+            = "uncommon.trap.verification.skipped";
+    public static final String UNCOMMON_TRAP_NAME = "uncommon.trap.name";
+    public static final String UNCOMMON_TRAP_BCI = "uncommon.trap.bci";
+    public static final String UNCOMMON_TRAP_COMMENT = "uncommon.trap.comment";
+    public static final String UNCOMMON_TRAP_ACTION = "uncommon.trap.action";
+    public static final String UNCOMMON_TRAP_SHOULD_EMITTED
+            = "uncommon.trap.emitted";
+    public static final String UNCOMMON_TRAP_SHOULD_FIRED
+            = "uncommon.trap.fired";
+
+    private static final String EMITTED_TRAP_PATTERN
+            = "<uncommon_trap bci='%s' reason='%s' action='%s' "
+                    + "comment='%s'";
+    private static final String FIRED_TRAP_PATTERN
+            = "<uncommon_trap thread='[0-9]*' reason='%s' action='%s'";
+    private static final String JVMS_PATTERN = "<jvms bci='%s'";
+
+    public static void main(String args[]) {
+        if (args.length == 0) {
+            throw new Error("At least one argument containing name of "
+                    + "compilation log file is expected");
+        }
+
+        for (String compLogFile : args) {
+            try {
+                verify(Paths.get(compLogFile));
+            } catch (IOException e) {
+                throw new Error("Unable to process compilation log.", e);
+            }
+        }
+    }
+
+    private static void verify(Path compLogFile) throws IOException {
+        Path propertiesFile = Paths.get(compLogFile.toString() +
+                PROPERTIES_FILE_SUFFIX);
+
+        Properties properties = new Properties();
+        properties.load(new FileReader(propertiesFile.toFile()));
+
+        if (Boolean.valueOf(properties.getProperty(
+                VERIFICATION_SHOULD_BE_SKIPPED, "false"))) {
+            System.out.println("Skipping verification for log file: "
+                    + compLogFile.toString());
+            return;
+        }
+
+        System.out.println("Verifying log file: " + compLogFile.toString());
+
+        List<String> compLogContent = Files.readAllLines(compLogFile);
+        verifyUncommonTrapEmitted(properties, compLogContent);
+        verifyUncommonTrapFired(properties, compLogContent);
+    }
+
+    private static void verifyUncommonTrapEmitted(Properties properties,
+            List<String> compLogContent)  {
+        String emittedTrapRE = String.format(EMITTED_TRAP_PATTERN,
+                properties.getProperty(UNCOMMON_TRAP_BCI, ".*"),
+                properties.getProperty(UNCOMMON_TRAP_NAME, ".*"),
+                properties.getProperty(UNCOMMON_TRAP_ACTION, ".*"),
+                properties.getProperty(UNCOMMON_TRAP_COMMENT, ".*"));
+        Pattern pattern = Pattern.compile(emittedTrapRE);
+
+        long trapsCount = compLogContent.stream()
+                .filter(line -> pattern.matcher(line).find())
+                .count();
+
+        boolean shouldBeEmitted = Boolean.valueOf(
+                properties.getProperty(UNCOMMON_TRAP_SHOULD_EMITTED));
+
+        Asserts.assertEQ(shouldBeEmitted, trapsCount > 0, String.format(
+                "Uncommon trap that matches following string in compilation log"
+                        + " should %sbe emitted: %s.",
+                (shouldBeEmitted ? " " : "not "), emittedTrapRE));
+    }
+
+    private static void verifyUncommonTrapFired(Properties properties,
+            List<String> compLogContent) {
+        String firedTrapRE = String.format(FIRED_TRAP_PATTERN,
+                properties.getProperty(UNCOMMON_TRAP_NAME, ".*"),
+                properties.getProperty(UNCOMMON_TRAP_ACTION, ".*"));
+        String jvmsRE = String.format(JVMS_PATTERN,
+                properties.getProperty(UNCOMMON_TRAP_BCI, ".*"));
+
+        boolean trapFired = false;
+        Pattern firedTrapPattern = Pattern.compile(firedTrapRE);
+        Pattern jvmsPattern = Pattern.compile(jvmsRE);
+
+        Iterator<String> iterator = compLogContent.iterator();
+        while (iterator.hasNext() && !trapFired) {
+            trapFired = firedTrapPattern.matcher(iterator.next()).find()
+                    && jvmsPattern.matcher(iterator.next()).find();
+        }
+
+        boolean shouldBeFired = Boolean.valueOf(
+                properties.getProperty(UNCOMMON_TRAP_SHOULD_FIRED));
+        Asserts.assertEQ(shouldBeFired, trapFired, String.format(
+                "Uncommon trap that matches following string in compilation log"
+                        + " should %sbe fired: %s.",
+                (shouldBeFired ? "" : "not "), firedTrapRE));
+    }
+}
+

hotspot/test/compiler/uncommontrap/TestUnstableIfTrap.java

+/*
+ * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.lang.reflect.Method;
+import java.util.Properties;
+
+import com.oracle.java.testlibrary.ByteCodeLoader;
+import com.oracle.java.testlibrary.Platform;
+import jdk.internal.org.objectweb.asm.ClassVisitor;
+import jdk.internal.org.objectweb.asm.ClassWriter;
+import jdk.internal.org.objectweb.asm.Label;
+import jdk.internal.org.objectweb.asm.MethodVisitor;
+import static jdk.internal.org.objectweb.asm.Opcodes.*;
+
+import sun.hotspot.WhiteBox;
+import uncommontrap.Verifier;
+
+/*
+ * @test
+ * @bug 8030976 8059226
+ * @library /testlibrary /compiler/testlibrary /../../test/lib
+ * @build TestUnstableIfTrap com.oracle.java.testlibrary.* uncommontrap.Verifier
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ *                              sun.hotspot.WhiteBox$WhiteBoxPermission
+ * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
+ *                   -XX:+WhiteBoxAPI -XX:+LogCompilation
+ *                   -XX:CompileCommand=compileonly,UnstableIfExecutable.test
+ *                   -XX:LogFile=always_taken_not_fired.xml
+ *                   TestUnstableIfTrap ALWAYS_TAKEN false
+ * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
+ *                   -XX:+WhiteBoxAPI -XX:+LogCompilation
+ *                   -XX:CompileCommand=compileonly,UnstableIfExecutable.test
+ *                   -XX:LogFile=always_taken_fired.xml
+ *                   TestUnstableIfTrap ALWAYS_TAKEN true
+ * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
+ *                   -XX:+WhiteBoxAPI -XX:+LogCompilation
+ *                   -XX:CompileCommand=compileonly,UnstableIfExecutable.test
+ *                   -XX:LogFile=never_taken_not_fired.xml
+ *                   TestUnstableIfTrap NEVER_TAKEN false
+ * @run main/othervm -Xbatch -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions
+ *                   -XX:+WhiteBoxAPI -XX:+LogCompilation
+ *                   -XX:CompileCommand=compileonly,UnstableIfExecutable.test
+ *                   -XX:LogFile=never_taken_fired.xml
+ *                   TestUnstableIfTrap NEVER_TAKEN true
+ * @run main uncommontrap.Verifier always_taken_not_fired.xml
+ *                                 always_taken_fired.xml
+ *                                 never_taken_not_fired.xml
+ *                                 never_taken_fired.xml
+ */
+public class TestUnstableIfTrap {
+    private static final WhiteBox WB = WhiteBox.getWhiteBox();
+    private static final String CLASS_NAME = "UnstableIfExecutable";
+    private static final String METHOD_NAME = "test";
+    private static final String FIELD_NAME = "field";
+    private static final int ITERATIONS = 1_000_000;
+    // There is no dependency on particular class file version, so it could be
+    // set to any version (if you're updating this test for Java 42).
+    private static final int CLASS_FILE_VERSION = 49;
+    private static final int MAX_TIER = 4;
+    // This test aimed to verify that uncommon trap with reason "unstable_if"
+    // is emitted when method that contain control-flow divergence such that
+    // one of two branches is never taken (and other one is taken always).
+    // C2 will made a decision whether or not the branch was ever taken
+    // depending on method's profile.
+    // If profile was collected for a few method's invocations, then C2 will not
+    // trust in branches' probabilities and the tested trap won't be emitted.
+    // In fact, a method has to be invoked at least 40 time at the day when this
+    // comment was written (see Parse::dynamic_branch_prediction for an actual
+    // value). It would be to implementation dependent to use "40" as
+    // a threshold value in the test, so in order to improve test's robustness
+    // the threshold value is 1000: if the tested method was compiled by C2
+    // before it was invoked 1000 times, then we won't verify that trap was
+    // emitted and fired.
+    private static final int MIN_INVOCATIONS_BEFORE_C2_COMPILATION = 1000;
+    /**
+     * Description of test case parameters and uncommon trap that will
+     * be emitted during tested method compilation.
+     */
+    private static enum TestCaseName {
+        ALWAYS_TAKEN(false, "taken always"),
+        NEVER_TAKEN(true, "taken never");
+        TestCaseName(boolean predicate, String comment) {
+            this.predicate = predicate;
+            this.comment = comment;
+        }
+
+        public final boolean predicate;
+        public final String name = "unstable_if";
+        public final String comment;
+    }
+
+    public static void main(String args[]) {
+        if (args.length != 2) {
+            throw new Error("Expected two arguments: test case name and a "
+                    + "boolean determining if uncommon trap should be fired.");
+        }
+        test(TestCaseName.valueOf(args[0]), Boolean.valueOf(args[1]));
+    }
+
+    private static void test(TestCaseName testCase, boolean shouldBeFired) {
+        Method testMethod;
+        Label unstableIfLocation = new Label();
+        boolean shouldBeEmitted;
+        boolean compiledToEarly = false;
+
+        try {
+            Class testClass = ByteCodeLoader.load(CLASS_NAME,
+                    generateTest(unstableIfLocation));
+            testMethod = testClass.getDeclaredMethod(METHOD_NAME,
+                    boolean.class);
+            for (int i = 0; i < ITERATIONS; i++) {
+                testMethod.invoke(null, testCase.predicate);
+                if (i < MIN_INVOCATIONS_BEFORE_C2_COMPILATION
+                        && isMethodCompiledByC2(testMethod)) {
+                    compiledToEarly = true;
+                    // There is no sense in further invocations: we already
+                    // decided to avoid verification.
+                    break;
+                }
+            }
+            // We're checking that trap should be emitted (i.e. it was compiled
+            // by C2) before the trap is fired, because otherwise the nmethod
+            // will be deoptimized and isMethodCompiledByC2 will return false.
+            shouldBeEmitted = isMethodCompiledByC2(testMethod)
+                    && !compiledToEarly;
+            if (shouldBeFired) {
+                testMethod.invoke(null, !testCase.predicate);
+            }
+        } catch (ReflectiveOperationException e) {
+            throw new Error("Test case should be generated, loaded and executed"
+                    + " without any issues.", e);
+        }
+
+        shouldBeFired &= shouldBeEmitted;
+
+        Properties properties = new Properties();
+        properties.setProperty(Verifier.VERIFICATION_SHOULD_BE_SKIPPED,
+                Boolean.toString(compiledToEarly));
+        properties.setProperty(Verifier.UNCOMMON_TRAP_SHOULD_EMITTED,
+                Boolean.toString(shouldBeEmitted));
+        properties.setProperty(Verifier.UNCOMMON_TRAP_SHOULD_FIRED,
+                Boolean.toString(shouldBeFired));
+        properties.setProperty(Verifier.UNCOMMON_TRAP_NAME, testCase.name);
+        properties.setProperty(Verifier.UNCOMMON_TRAP_COMMENT,
+                testCase.comment);
+        properties.setProperty(Verifier.UNCOMMON_TRAP_BCI,
+                Integer.toString(unstableIfLocation.getOffset()));
+
+        properties.list(System.out);
+
+        File f = new File(WB.getStringVMFlag("LogFile") +
+                Verifier.PROPERTIES_FILE_SUFFIX);
+        try (FileWriter wr = new FileWriter(f)) {
+            properties.store(wr, "");
+        } catch (IOException e) {
+            throw new Error("Unable to store test properties.", e);
+        }
+    }
+
+    private static boolean isMethodCompiledByC2(Method m) {
+        boolean isTiered = WB.getBooleanVMFlag("TieredCompilation");
+        boolean isMethodCompiled = WB.isMethodCompiled(m);
+        boolean isMethodCompiledAtMaxTier
+                = WB.getMethodCompilationLevel(m) == MAX_TIER;
+
+        return Platform.isServer() && isMethodCompiled
+                && (!isTiered || isMethodCompiledAtMaxTier);
+    }
+
+    /**
+     * Generates class with name {@code CLASS_NAME}, which will contain a
+     * static method {@code METHOD_NAME}:
+     *
+     * <pre>{@code
+     * public abstract class UnstableIfExecutable {
+     *   private static int field = 0;
+     *
+     *   public static void test(boolean alwaysTrue) {
+     *     if (alwaysTrue) {
+     *       field++;
+     *     } else {
+     *       field--;
+     *     }
+     *   }
+     * }
+     * }</pre>
+     *
+     * @return generated bytecode.
+     */
+    private static byte[] generateTest(Label unstableIfLocation) {
+        ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
+
+        cw.visit(CLASS_FILE_VERSION, ACC_PUBLIC | ACC_ABSTRACT, CLASS_NAME,
+                null, "java/lang/Object", null);
+
+        cw.visitField(ACC_PUBLIC | ACC_STATIC | ACC_VOLATILE, FIELD_NAME,
+                "I", null, Integer.valueOf(0));
+
+        generateTestMethod(cw, unstableIfLocation);
+
+        return cw.toByteArray();
+    }
+
+    private static void generateTestMethod(ClassVisitor cv,
+            Label unstableIfLocation) {
+        MethodVisitor mv = cv.visitMethod(ACC_PUBLIC | ACC_STATIC, METHOD_NAME,
+                "(Z)V", null, null);
+        mv.visitCode();
+
+        Label end = new Label();
+        Label falseBranch = new Label();
+
+        // push "field" field's value and 1 to stack
+        mv.visitFieldInsn(GETSTATIC, CLASS_NAME, FIELD_NAME, "I");
+        mv.visitInsn(ICONST_1);
+        // load argument's value
+        mv.visitVarInsn(ILOAD, 0); // alwaysTrue
+        // here is our unstable if
+        mv.visitLabel(unstableIfLocation);
+        mv.visitJumpInsn(IFEQ, falseBranch);
+        // increment on "true"
+        mv.visitInsn(IADD);
+        mv.visitJumpInsn(GOTO, end);
+        // decrement on "false"
+        mv.visitLabel(falseBranch);
+        mv.visitInsn(ISUB);
+        mv.visitLabel(end);
+        // bye bye
+        mv.visitInsn(RETURN);
+
+        mv.visitMaxs(0, 0);
+        mv.visitEnd();
+    }
+}
+