/*
 * Copyright (c) 2015, 2022, 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
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 *
 * 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.
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 */

/*
 * @test
 * @bug 8143628
 * @summary Test unsafe access for char
 *
 * @modules jdk.unsupported/sun.misc
 * @run testng/othervm -Diters=100   -Xint                   compiler.unsafe.SunMiscUnsafeAccessTestChar
 * @run testng/othervm -Diters=20000 -XX:TieredStopAtLevel=1 compiler.unsafe.SunMiscUnsafeAccessTestChar
 * @run testng/othervm -Diters=20000 -XX:-TieredCompilation  compiler.unsafe.SunMiscUnsafeAccessTestChar
 * @run testng/othervm -Diters=20000                         compiler.unsafe.SunMiscUnsafeAccessTestChar
 */

package compiler.unsafe;

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);

    // More resilience for Weak* tests. These operations may spuriously
    // fail, and so we do several attempts with delay on failure.
    // Be mindful of worst-case total time on test, which would be at
    // roughly (delay*attempts) milliseconds.
    //
    static final int WEAK_ATTEMPTS = Integer.getInteger("weakAttempts", 100);
    static final int WEAK_DELAY_MS = Math.max(1, Integer.getInteger("weakDelay", 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 void weakDelay() {
        try {
            if (WEAK_DELAY_MS > 0) {
                Thread.sleep(WEAK_DELAY_MS);
            }
        } catch (InterruptedException ie) {
            // Do nothing.
        }
    }

    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, '\u0123');
            char x = UNSAFE.getChar(base, offset);
            assertEquals(x, '\u0123', "set char value");
        }

        // Volatile
        {
            UNSAFE.putCharVolatile(base, offset, '\u4567');
            char x = UNSAFE.getCharVolatile(base, offset);
            assertEquals(x, '\u4567', "putVolatile char value");
        }


    }

    static void testAccess(long address) {
        // Plain
        {
            UNSAFE.putChar(address, '\u0123');
            char x = UNSAFE.getChar(address);
            assertEquals(x, '\u0123', "set char value");
        }
    }
}