/*

 * 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 8143628

 * @summary Test unsafe access for char

 * @modules java.base/sun.misc

 * @run testng/othervm -Diters=100   -Xint                   SunMiscUnsafeAccessTestChar

 * @run testng/othervm -Diters=20000 -XX:TieredStopAtLevel=1 SunMiscUnsafeAccessTestChar

 * @run testng/othervm -Diters=20000 -XX:-TieredCompilation  SunMiscUnsafeAccessTestChar

 * @run testng/othervm -Diters=20000                         SunMiscUnsafeAccessTestChar

 */

import org.testng.annotations.Test;

import java.lang.reflect.Field;

import static org.testng.Assert.*;

public class SunMiscUnsafeAccessTestChar {

    static final int ITERS = Integer.getInteger("iters", 1);

    static final sun.misc.Unsafe UNSAFE;

    static final long V_OFFSET;

    static final Object STATIC_V_BASE;

    static final long STATIC_V_OFFSET;

    static int ARRAY_OFFSET;

    static int ARRAY_SHIFT;

    static {

        try {

            Field f = sun.misc.Unsafe.class.getDeclaredField("theUnsafe");

            f.setAccessible(true);

            UNSAFE = (sun.misc.Unsafe) f.get(null);

        } catch (Exception e) {

            throw new RuntimeException("Unable to get Unsafe instance.", e);

        }

        try {

            Field staticVField = SunMiscUnsafeAccessTestChar.class.getDeclaredField("static_v");

            STATIC_V_BASE = UNSAFE.staticFieldBase(staticVField);

            STATIC_V_OFFSET = UNSAFE.staticFieldOffset(staticVField);

        } catch (Exception e) {

            throw new RuntimeException(e);

        }

        try {

            Field vField = SunMiscUnsafeAccessTestChar.class.getDeclaredField("v");

            V_OFFSET = UNSAFE.objectFieldOffset(vField);

        } catch (Exception e) {

            throw new RuntimeException(e);

        }

        ARRAY_OFFSET = UNSAFE.arrayBaseOffset(char[].class);

        int ascale = UNSAFE.arrayIndexScale(char[].class);

        ARRAY_SHIFT = 31 - Integer.numberOfLeadingZeros(ascale);

    }

    static char static_v;

    char v;

    @Test

    public void testFieldInstance() {

        SunMiscUnsafeAccessTestChar t = new SunMiscUnsafeAccessTestChar();

        for (int c = 0; c < ITERS; c++) {

            testAccess(t, V_OFFSET);

        }

    }

    @Test

    public void testFieldStatic() {

        for (int c = 0; c < ITERS; c++) {

            testAccess(STATIC_V_BASE, STATIC_V_OFFSET);

        }

    }

    @Test

    public void testArray() {

        char[] array = new char[10];

        for (int c = 0; c < ITERS; c++) {

            for (int i = 0; i < array.length; i++) {

                testAccess(array, (((long) i) << ARRAY_SHIFT) + ARRAY_OFFSET);

            }

        }

    }

    @Test

    public void testArrayOffHeap() {

        int size = 10;

        long address = UNSAFE.allocateMemory(size << ARRAY_SHIFT);

        try {

            for (int c = 0; c < ITERS; c++) {

                for (int i = 0; i < size; i++) {

                    testAccess(null, (((long) i) << ARRAY_SHIFT) + address);

                }

            }

        } finally {

            UNSAFE.freeMemory(address);

        }

    }

    @Test

    public void testArrayOffHeapDirect() {

        int size = 10;

        long address = UNSAFE.allocateMemory(size << ARRAY_SHIFT);

        try {

            for (int c = 0; c < ITERS; c++) {

                for (int i = 0; i < size; i++) {

                    testAccess((((long) i) << ARRAY_SHIFT) + address);

                }

            }

        } finally {

            UNSAFE.freeMemory(address);

        }

    }

    static void testAccess(Object base, long offset) {

        // Plain

        {

            UNSAFE.putChar(base, offset, 'a');

            char x = UNSAFE.getChar(base, offset);

            assertEquals(x, 'a', "set char value");

        }

        // Volatile

        {

            UNSAFE.putCharVolatile(base, offset, 'b');

            char x = UNSAFE.getCharVolatile(base, offset);

            assertEquals(x, 'b', "putVolatile char value");

        }

    }

    static void testAccess(long address) {

        // Plain

        {

            UNSAFE.putChar(address, 'a');

            char x = UNSAFE.getChar(address);

            assertEquals(x, 'a', "set char value");

        }

    }

}