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/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * The Universal Permissive License (UPL), Version 1.0
 *
 * Subject to the condition set forth below, permission is hereby granted to any
 * person obtaining a copy of this software, associated documentation and/or
 * data (collectively the "Software"), free of charge and under any and all
 * copyright rights in the Software, and any and all patent rights owned or
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 * unmodified Software as contributed to or provided by such licensor, or (ii)
 * the Larger Works (as defined below), to deal in both
 *
 * (a) the Software, and
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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
 * one is included with the Software each a "Larger Work" to which the Software
 * is contributed by such licensors),
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 * Software and the Larger Work(s), and to sublicense the foregoing rights on
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 * This license is subject to the following condition:
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 * The above copyright notice and either this complete permission notice or at a
 * minimum a reference to the UPL must be included in all copies or substantial
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package com.oracle.truffle.object;

import java.lang.reflect.Field;

import sun.misc.Unsafe;

final class UnsafeAccess {

    private static final Unsafe UNSAFE = getUnsafe();

    static final long ARRAY_INT_BASE_OFFSET = UNSAFE.arrayBaseOffset(int[].class);
    static final long ARRAY_INT_INDEX_SCALE = UNSAFE.arrayIndexScale(int[].class);

    @SuppressWarnings("deprecation")
    static long objectFieldOffset(Field field) {
        return UNSAFE.objectFieldOffset(field);
    }

    static Object unsafeGetObject(Object receiver, long offset) {
        return UNSAFE.getObject(receiver, offset);
    }

    static void unsafePutObject(Object receiver, long offset, Object value) {
        UNSAFE.putObject(receiver, offset, value);
    }

    static long unsafeGetLong(Object receiver, long offset) {
        return UNSAFE.getLong(receiver, offset);
    }

    static void unsafePutLong(Object receiver, long offset, long value) {
        UNSAFE.putLong(receiver, offset, value);
    }

    @SuppressWarnings("unused")
    static long unsafeGetLong(Object receiver, long offset, boolean condition, Object locationIdentity) {
        return UNSAFE.getLong(receiver, offset);
    }

    @SuppressWarnings("unused")
    static void unsafePutLong(Object receiver, long offset, long value, Object locationIdentity) {
        UNSAFE.putLong(receiver, offset, value);
    }

    private UnsafeAccess() {
    }

    private static Unsafe getUnsafe() {
        try {
            return Unsafe.getUnsafe();
        } catch (SecurityException e) {
        }
        try {
            Field theUnsafeInstance = Unsafe.class.getDeclaredField("theUnsafe");
            theUnsafeInstance.setAccessible(true);
            return (Unsafe) theUnsafeInstance.get(Unsafe.class);
        } catch (Exception e) {
            throw new RuntimeException("exception while trying to get Unsafe.theUnsafe via reflection:", e);
        }
    }
}