/*

 * Copyright (c) 2015, 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.

 */

/*

 * @test

 * @bug 8072008

 * @library /testlibrary /../../test/lib

 * @build RedefineTest Agent

 * @run main ClassFileInstaller sun.hotspot.WhiteBox

 *                              sun.hotspot.WhiteBox$WhiteBoxPermission

 *                              java.lang.invoke.RedefineTest

 *                              Agent

 *                              jdk.test.lib.Asserts

 * @run main Agent agent.jar java.lang.invoke.RedefineTest

 * @run main/othervm -Xbootclasspath/a:. -javaagent:agent.jar

 *                   -XX:+IgnoreUnrecognizedVMOptions

 *                   -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI

 *                   -Xbatch -XX:-TieredCompilation -XX:CICompilerCount=1

 *                      java.lang.invoke.RedefineTest

 */

package java.lang.invoke;

import sun.hotspot.WhiteBox;

import sun.misc.Unsafe;

import jdk.internal.org.objectweb.asm.*;

import java.lang.instrument.ClassDefinition;

import java.lang.instrument.Instrumentation;

import static jdk.internal.org.objectweb.asm.Opcodes.*;

public class RedefineTest {

    static final MethodHandles.Lookup LOOKUP = MethodHandles.Lookup.IMPL_LOOKUP;

    static final Unsafe UNSAFE = Unsafe.getUnsafe();

    static final String NAME = "java/lang/invoke/RedefineTest$T";

    static Class<?> getClass(int r) {

        byte[] classFile = getClassFile(r);

        return UNSAFE.defineClass(NAME, classFile, 0, classFile.length, null, null);

    }

    /**

     * Generates a class of the following shape:

     *     static class T {

     *         @DontInline public static int f() { return $r; }

     *     }

     */

    static byte[] getClassFile(int r) {

        ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS);

        MethodVisitor mv;

        cw.visit(52, ACC_PUBLIC | ACC_SUPER, NAME, null, "java/lang/Object", null);

        {

            mv = cw.visitMethod(ACC_PUBLIC | ACC_STATIC, "f", "()I", null, null);

            mv.visitAnnotation("Ljava/lang/invoke/DontInline;", true);

            mv.visitCode();

            mv.visitLdcInsn(r);

            mv.visitInsn(IRETURN);

            mv.visitMaxs(0, 0);

            mv.visitEnd();

        }

        cw.visitEnd();

        return cw.toByteArray();

    }

    static final MethodHandle mh;

    static final Class<?> CLS = getClass(0);

    static {

        try {

            mh = LOOKUP.findStatic(CLS, "f", MethodType.methodType(int.class));

        } catch (Exception e) {

            throw new Error(e);

        }

    }

    static final WhiteBox WB = WhiteBox.getWhiteBox();

    @DontInline

    static int invokeBasic() {

        try {

            return (int)mh.invokeExact();

        } catch (Throwable e) {

            throw new Error(e);

        }

    }

    static Instrumentation instr;

    public static void premain(String args, Instrumentation instr) {

        RedefineTest.instr = instr;

    }

    public static void main(String[] args) throws Exception {

        for (int i = 0; i < 20_000; i++) {

            int r = invokeBasic();

            if (r != 0) {

                throw new Error(r + " != 0");

            }

        }

        // WB.ensureCompiled();

        redefine();

        int exp = (instr != null) ? 1 : 0;

        for (int i = 0; i < 20_000; i++) {

            if (invokeBasic() != exp) {

                throw new Error();

            }

        }

        WB.clearInlineCaches();

        for (int i = 0; i < 20_000; i++) {

            if (invokeBasic() != exp) {

                throw new Error();

            }

        }

        // WB.ensureCompiled();

    }

    static void redefine() {

        if (instr == null) {

            System.out.println("NOT REDEFINED");

            return;

        }

        ClassDefinition cd = new ClassDefinition(CLS, getClassFile(1));

        try {

            instr.redefineClasses(cd);

        } catch (Exception e) {

            throw new Error(e);

        }

        System.out.println("REDEFINED");

    }

}