jdk/test/hotspot/jtreg/compiler/locks/TestNestedSynchronize.java

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/**
 * @test
 * @bug 8322996 8324839 8325467
 * @summary Ensure C2 can compile deeply nested synchronize statements.
 *          Exercises C2 register masks, in particular. We incrementally
 *          increase the level of nesting (up to 100) to trigger potential edge
 *          cases.
 * @modules java.base/jdk.internal.misc
 * @library /test/lib /
 * @run main/othervm -XX:CompileCommand=compileonly,Test::test*
 *                   -Xcomp
 *                   -XX:+UnlockDiagnosticVMOptions
 *                   -XX:+AbortVMOnCompilationFailure
 *                   compiler.locks.TestNestedSynchronize
 * @run main compiler.locks.TestNestedSynchronize
 */

package compiler.locks;

import compiler.lib.compile_framework.*;
import java.util.LinkedList;

public class TestNestedSynchronize {
    static int min = 1;
    static int max = 100;
    static String test_class_name = "Test";
    static String test_method_name = "test";

    // The below method generates a program of the form:
    //
    // public class Test {
    //     public static void test1() {
    //         synchronized (Test.class) {
    //         }
    //     }
    //
    //     public static void test2() {
    //         synchronized (Test.class) {
    //         synchronized (Test.class) {
    //         }
    //         }
    //     }
    //
    //     public static void test3() {
    //         synchronized (Test.class) {
    //         synchronized (Test.class) {
    //         synchronized (Test.class) {
    //         }
    //         }
    //         }
    //     }
    //
    //     ...
    //
    //     public static void test100() {
    //         synchronized (Test.class) {
    //         synchronized (Test.class) {
    //         synchronized (Test.class) {
    //         ...
    //         }
    //         }
    //         }
    //     }
    // }
    //
    // The above is a massive program. Therefore, we do not directly inline the
    // program in TestNestedSynchronize and instead compile and run it via the
    // CompileFramework.
    public static String generate_test() {
        LinkedList<String> acc = new LinkedList<String>();
        for (int i = min; i <= max; i++) {
            LinkedList<String> method = new LinkedList<String>();
            for (int j = 0; j < i; j++) {
                method.addFirst(String.format(
                    "        synchronized (%s.class) {", test_class_name));
                method.addLast("        }");
            }
            method.addFirst(String.format(
                "    public static void %s%d() {", test_method_name, i));
            method.addLast("    }");
            acc.addAll(method);
        }
        acc.addFirst(String.format("public class %s {", test_class_name));
        acc.addLast("}");
        return String.join("\n", acc);
    }

    public static void main(String[] args) {
        CompileFramework comp = new CompileFramework();
        comp.addJavaSourceCode(test_class_name, generate_test());
        comp.compile();
        for (int i = min; i <= max; i++) {
            comp.invoke(test_class_name, test_method_name + i, new Object[] {});
        }
    }
}