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	/*
	* Copyright (c) 2000, 2013, 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. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* 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.
	*/

	package sun.misc;

	import java.security.*;
	import java.lang.reflect.*;

	import sun.reflect.CallerSensitive;
	import sun.reflect.Reflection;


	/**
	* A collection of methods for performing low-level, unsafe operations.
	* Although the class and all methods are public, use of this class is
	* limited because only trusted code can obtain instances of it.
	*
	* @author John R. Rose
	* @see #getUnsafe
	*/

	public final class Unsafe {

	private static native void registerNatives();
	static {
	registerNatives();
	sun.reflect.Reflection.registerMethodsToFilter(Unsafe.class, "getUnsafe");
	}

	private Unsafe() {}

	private static final Unsafe theUnsafe = new Unsafe();

	/**
	* Provides the caller with the capability of performing unsafe
	* operations.
	*
	* <p> The returned <code>Unsafe</code> object should be carefully guarded
	* by the caller, since it can be used to read and write data at arbitrary
	* memory addresses. It must never be passed to untrusted code.
	*
	* <p> Most methods in this class are very low-level, and correspond to a
	* small number of hardware instructions (on typical machines). Compilers
	* are encouraged to optimize these methods accordingly.
	*
	* <p> Here is a suggested idiom for using unsafe operations:
	*
	* <blockquote><pre>
	* class MyTrustedClass {
	* private static final Unsafe unsafe = Unsafe.getUnsafe();
	* ...
	* private long myCountAddress = ...;
	* public int getCount() { return unsafe.getByte(myCountAddress); }
	* }
	* </pre></blockquote>
	*
	* (It may assist compilers to make the local variable be
	* <code>final</code>.)
	*
	* @exception SecurityException if a security manager exists and its
	* <code>checkPropertiesAccess</code> method doesn't allow
	* access to the system properties.
	*/
	@CallerSensitive
	public static Unsafe getUnsafe() {
	Class<?> caller = Reflection.getCallerClass();
	if (!VM.isSystemDomainLoader(caller.getClassLoader()))
	throw new SecurityException("Unsafe");
	return theUnsafe;
	}

	/// peek and poke operations
	/// (compilers should optimize these to memory ops)

	// These work on object fields in the Java heap.
	// They will not work on elements of packed arrays.

	/**
	* Fetches a value from a given Java variable.
	* More specifically, fetches a field or array element within the given
	* object <code>o</code> at the given offset, or (if <code>o</code> is
	* null) from the memory address whose numerical value is the given
	* offset.
	* <p>
	* The results are undefined unless one of the following cases is true:
	* <ul>
	* <li>The offset was obtained from {@link #objectFieldOffset} on
	* the {@link java.lang.reflect.Field} of some Java field and the object
	* referred to by <code>o</code> is of a class compatible with that
	* field's class.
	*
	* <li>The offset and object reference <code>o</code> (either null or
	* non-null) were both obtained via {@link #staticFieldOffset}
	* and {@link #staticFieldBase} (respectively) from the
	* reflective {@link Field} representation of some Java field.
	*
	* <li>The object referred to by <code>o</code> is an array, and the offset
	* is an integer of the form <code>B+N*S</code>, where <code>N</code> is
	* a valid index into the array, and <code>B</code> and <code>S</code> are
	* the values obtained by {@link #arrayBaseOffset} and {@link
	* #arrayIndexScale} (respectively) from the array's class. The value
	* referred to is the <code>N</code><em>th</em> element of the array.
	*
	* </ul>
	* <p>
	* If one of the above cases is true, the call references a specific Java
	* variable (field or array element). However, the results are undefined
	* if that variable is not in fact of the type returned by this method.
	* <p>
	* This method refers to a variable by means of two parameters, and so
	* it provides (in effect) a <em>double-register</em> addressing mode
	* for Java variables. When the object reference is null, this method
	* uses its offset as an absolute address. This is similar in operation
	* to methods such as {@link #getInt(long)}, which provide (in effect) a
	* <em>single-register</em> addressing mode for non-Java variables.
	* However, because Java variables may have a different layout in memory
	* from non-Java variables, programmers should not assume that these
	* two addressing modes are ever equivalent. Also, programmers should
	* remember that offsets from the double-register addressing mode cannot
	* be portably confused with longs used in the single-register addressing
	* mode.
	*
	* @param o Java heap object in which the variable resides, if any, else
	* null
	* @param offset indication of where the variable resides in a Java heap
	* object, if any, else a memory address locating the variable
	* statically
	* @return the value fetched from the indicated Java variable
	* @throws RuntimeException No defined exceptions are thrown, not even
	* {@link NullPointerException}
	*/
	public native int getInt(Object o, long offset);

	/**
	* Stores a value into a given Java variable.
	* <p>
	* The first two parameters are interpreted exactly as with
	* {@link #getInt(Object, long)} to refer to a specific
	* Java variable (field or array element). The given value
	* is stored into that variable.
	* <p>
	* The variable must be of the same type as the method
	* parameter <code>x</code>.
	*
	* @param o Java heap object in which the variable resides, if any, else
	* null
	* @param offset indication of where the variable resides in a Java heap
	* object, if any, else a memory address locating the variable
	* statically
	* @param x the value to store into the indicated Java variable
	* @throws RuntimeException No defined exceptions are thrown, not even
	* {@link NullPointerException}
	*/
	public native void putInt(Object o, long offset, int x);

	/**
	* Fetches a reference value from a given Java variable.
	* @see #getInt(Object, long)
	*/
	public native Object getObject(Object o, long offset);

	/**
	* Stores a reference value into a given Java variable.
	* <p>
	* Unless the reference <code>x</code> being stored is either null
	* or matches the field type, the results are undefined.
	* If the reference <code>o</code> is non-null, car marks or
	* other store barriers for that object (if the VM requires them)
	* are updated.
	* @see #putInt(Object, int, int)
	*/
	public native void putObject(Object o, long offset, Object x);

	/** @see #getInt(Object, long) */
	public native boolean getBoolean(Object o, long offset);
	/** @see #putInt(Object, int, int) */
	public native void putBoolean(Object o, long offset, boolean x);
	/** @see #getInt(Object, long) */
	public native byte getByte(Object o, long offset);
	/** @see #putInt(Object, int, int) */
	public native void putByte(Object o, long offset, byte x);
	/** @see #getInt(Object, long) */
	public native short getShort(Object o, long offset);
	/** @see #putInt(Object, int, int) */
	public native void putShort(Object o, long offset, short x);
	/** @see #getInt(Object, long) */
	public native char getChar(Object o, long offset);
	/** @see #putInt(Object, int, int) */
	public native void putChar(Object o, long offset, char x);
	/** @see #getInt(Object, long) */
	public native long getLong(Object o, long offset);
	/** @see #putInt(Object, int, int) */
	public native void putLong(Object o, long offset, long x);
	/** @see #getInt(Object, long) */
	public native float getFloat(Object o, long offset);
	/** @see #putInt(Object, int, int) */
	public native void putFloat(Object o, long offset, float x);
	/** @see #getInt(Object, long) */
	public native double getDouble(Object o, long offset);
	/** @see #putInt(Object, int, int) */
	public native void putDouble(Object o, long offset, double x);

	/**
	* This method, like all others with 32-bit offsets, was native
	* in a previous release but is now a wrapper which simply casts
	* the offset to a long value. It provides backward compatibility
	* with bytecodes compiled against 1.4.
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public int getInt(Object o, int offset) {
	return getInt(o, (long)offset);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public void putInt(Object o, int offset, int x) {
	putInt(o, (long)offset, x);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public Object getObject(Object o, int offset) {
	return getObject(o, (long)offset);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public void putObject(Object o, int offset, Object x) {
	putObject(o, (long)offset, x);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public boolean getBoolean(Object o, int offset) {
	return getBoolean(o, (long)offset);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public void putBoolean(Object o, int offset, boolean x) {
	putBoolean(o, (long)offset, x);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public byte getByte(Object o, int offset) {
	return getByte(o, (long)offset);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public void putByte(Object o, int offset, byte x) {
	putByte(o, (long)offset, x);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public short getShort(Object o, int offset) {
	return getShort(o, (long)offset);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public void putShort(Object o, int offset, short x) {
	putShort(o, (long)offset, x);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public char getChar(Object o, int offset) {
	return getChar(o, (long)offset);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public void putChar(Object o, int offset, char x) {
	putChar(o, (long)offset, x);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public long getLong(Object o, int offset) {
	return getLong(o, (long)offset);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public void putLong(Object o, int offset, long x) {
	putLong(o, (long)offset, x);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public float getFloat(Object o, int offset) {
	return getFloat(o, (long)offset);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public void putFloat(Object o, int offset, float x) {
	putFloat(o, (long)offset, x);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public double getDouble(Object o, int offset) {
	return getDouble(o, (long)offset);
	}

	/**
	* @deprecated As of 1.4.1, cast the 32-bit offset argument to a long.
	* See {@link #staticFieldOffset}.
	*/
	@Deprecated
	public void putDouble(Object o, int offset, double x) {
	putDouble(o, (long)offset, x);
	}

	// These work on values in the C heap.

	/**
	* Fetches a value from a given memory address. If the address is zero, or
	* does not point into a block obtained from {@link #allocateMemory}, the
	* results are undefined.
	*
	* @see #allocateMemory
	*/
	public native byte getByte(long address);

	/**
	* Stores a value into a given memory address. If the address is zero, or
	* does not point into a block obtained from {@link #allocateMemory}, the
	* results are undefined.
	*
	* @see #getByte(long)
	*/
	public native void putByte(long address, byte x);

	/** @see #getByte(long) */
	public native short getShort(long address);
	/** @see #putByte(long, byte) */
	public native void putShort(long address, short x);
	/** @see #getByte(long) */
	public native char getChar(long address);
	/** @see #putByte(long, byte) */
	public native void putChar(long address, char x);
	/** @see #getByte(long) */
	public native int getInt(long address);
	/** @see #putByte(long, byte) */
	public native void putInt(long address, int x);
	/** @see #getByte(long) */
	public native long getLong(long address);
	/** @see #putByte(long, byte) */
	public native void putLong(long address, long x);
	/** @see #getByte(long) */
	public native float getFloat(long address);
	/** @see #putByte(long, byte) */
	public native void putFloat(long address, float x);
	/** @see #getByte(long) */
	public native double getDouble(long address);
	/** @see #putByte(long, byte) */
	public native void putDouble(long address, double x);

	/**
	* Fetches a native pointer from a given memory address. If the address is
	* zero, or does not point into a block obtained from {@link
	* #allocateMemory}, the results are undefined.
	*
	* <p> If the native pointer is less than 64 bits wide, it is extended as
	* an unsigned number to a Java long. The pointer may be indexed by any
	* given byte offset, simply by adding that offset (as a simple integer) to
	* the long representing the pointer. The number of bytes actually read
	* from the target address maybe determined by consulting {@link
	* #addressSize}.
	*
	* @see #allocateMemory
	*/
	public native long getAddress(long address);

	/**
	* Stores a native pointer into a given memory address. If the address is
	* zero, or does not point into a block obtained from {@link
	* #allocateMemory}, the results are undefined.
	*
	* <p> The number of bytes actually written at the target address maybe
	* determined by consulting {@link #addressSize}.
	*
	* @see #getAddress(long)
	*/
	public native void putAddress(long address, long x);

	/// wrappers for malloc, realloc, free:

	/**
	* Allocates a new block of native memory, of the given size in bytes. The
	* contents of the memory are uninitialized; they will generally be
	* garbage. The resulting native pointer will never be zero, and will be
	* aligned for all value types. Dispose of this memory by calling {@link
	* #freeMemory}, or resize it with {@link #reallocateMemory}.
	*
	* @throws IllegalArgumentException if the size is negative or too large
	* for the native size_t type
	*
	* @throws OutOfMemoryError if the allocation is refused by the system
	*
	* @see #getByte(long)
	* @see #putByte(long, byte)
	*/
	public native long allocateMemory(long bytes);

	/**
	* Resizes a new block of native memory, to the given size in bytes. The
	* contents of the new block past the size of the old block are
	* uninitialized; they will generally be garbage. The resulting native
	* pointer will be zero if and only if the requested size is zero. The
	* resulting native pointer will be aligned for all value types. Dispose
	* of this memory by calling {@link #freeMemory}, or resize it with {@link
	* #reallocateMemory}. The address passed to this method may be null, in
	* which case an allocation will be performed.
	*
	* @throws IllegalArgumentException if the size is negative or too large
	* for the native size_t type
	*
	* @throws OutOfMemoryError if the allocation is refused by the system
	*
	* @see #allocateMemory
	*/
	public native long reallocateMemory(long address, long bytes);

	/**
	* Sets all bytes in a given block of memory to a fixed value
	* (usually zero).
	*
	* <p>This method determines a block's base address by means of two parameters,
	* and so it provides (in effect) a <em>double-register</em> addressing mode,
	* as discussed in {@link #getInt(Object,long)}. When the object reference is null,
	* the offset supplies an absolute base address.
	*
	* <p>The stores are in coherent (atomic) units of a size determined
	* by the address and length parameters. If the effective address and
	* length are all even modulo 8, the stores take place in 'long' units.
	* If the effective address and length are (resp.) even modulo 4 or 2,
	* the stores take place in units of 'int' or 'short'.
	*
	* @since 1.7
	*/
	public native void setMemory(Object o, long offset, long bytes, byte value);

	/**
	* Sets all bytes in a given block of memory to a fixed value
	* (usually zero). This provides a <em>single-register</em> addressing mode,
	* as discussed in {@link #getInt(Object,long)}.
	*
	* <p>Equivalent to <code>setMemory(null, address, bytes, value)</code>.
	*/
	public void setMemory(long address, long bytes, byte value) {
	setMemory(null, address, bytes, value);
	}

	/**
	* Sets all bytes in a given block of memory to a copy of another
	* block.
	*
	* <p>This method determines each block's base address by means of two parameters,
	* and so it provides (in effect) a <em>double-register</em> addressing mode,
	* as discussed in {@link #getInt(Object,long)}. When the object reference is null,
	* the offset supplies an absolute base address.
	*
	* <p>The transfers are in coherent (atomic) units of a size determined
	* by the address and length parameters. If the effective addresses and
	* length are all even modulo 8, the transfer takes place in 'long' units.
	* If the effective addresses and length are (resp.) even modulo 4 or 2,
	* the transfer takes place in units of 'int' or 'short'.
	*
	* @since 1.7
	*/
	public native void copyMemory(Object srcBase, long srcOffset,
	Object destBase, long destOffset,
	long bytes);
	/**
	* Sets all bytes in a given block of memory to a copy of another
	* block. This provides a <em>single-register</em> addressing mode,
	* as discussed in {@link #getInt(Object,long)}.
	*
	* Equivalent to <code>copyMemory(null, srcAddress, null, destAddress, bytes)</code>.
	*/
	public void copyMemory(long srcAddress, long destAddress, long bytes) {
	copyMemory(null, srcAddress, null, destAddress, bytes);
	}

	/**
	* Disposes of a block of native memory, as obtained from {@link
	* #allocateMemory} or {@link #reallocateMemory}. The address passed to
	* this method may be null, in which case no action is taken.
	*
	* @see #allocateMemory
	*/
	public native void freeMemory(long address);

	/// random queries

	/**
	* This constant differs from all results that will ever be returned from
	* {@link #staticFieldOffset}, {@link #objectFieldOffset},
	* or {@link #arrayBaseOffset}.
	*/
	public static final int INVALID_FIELD_OFFSET = -1;

	/**
	* Returns the offset of a field, truncated to 32 bits.
	* This method is implemented as follows:
	* <blockquote><pre>
	* public int fieldOffset(Field f) {
	* if (Modifier.isStatic(f.getModifiers()))
	* return (int) staticFieldOffset(f);
	* else
	* return (int) objectFieldOffset(f);
	* }
	* </pre></blockquote>
	* @deprecated As of 1.4.1, use {@link #staticFieldOffset} for static
	* fields and {@link #objectFieldOffset} for non-static fields.
	*/
	@Deprecated
	public int fieldOffset(Field f) {
	if (Modifier.isStatic(f.getModifiers()))
	return (int) staticFieldOffset(f);
	else
	return (int) objectFieldOffset(f);
	}

	/**
	* Returns the base address for accessing some static field
	* in the given class. This method is implemented as follows:
	* <blockquote><pre>
	* public Object staticFieldBase(Class c) {
	* Field[] fields = c.getDeclaredFields();
	* for (int i = 0; i < fields.length; i++) {
	* if (Modifier.isStatic(fields[i].getModifiers())) {
	* return staticFieldBase(fields[i]);
	* }
	* }
	* return null;
	* }
	* </pre></blockquote>
	* @deprecated As of 1.4.1, use {@link #staticFieldBase(Field)}
	* to obtain the base pertaining to a specific {@link Field}.
	* This method works only for JVMs which store all statics
	* for a given class in one place.
	*/
	@Deprecated
	public Object staticFieldBase(Class<?> c) {
	Field[] fields = c.getDeclaredFields();
	for (int i = 0; i < fields.length; i++) {
	if (Modifier.isStatic(fields[i].getModifiers())) {
	return staticFieldBase(fields[i]);
	}
	}
	return null;
	}

	/**
	* Report the location of a given field in the storage allocation of its
	* class. Do not expect to perform any sort of arithmetic on this offset;
	* it is just a cookie which is passed to the unsafe heap memory accessors.
	*
	* <p>Any given field will always have the same offset and base, and no
	* two distinct fields of the same class will ever have the same offset
	* and base.
	*
	* <p>As of 1.4.1, offsets for fields are represented as long values,
	* although the Sun JVM does not use the most significant 32 bits.
	* However, JVM implementations which store static fields at absolute
	* addresses can use long offsets and null base pointers to express
	* the field locations in a form usable by {@link #getInt(Object,long)}.
	* Therefore, code which will be ported to such JVMs on 64-bit platforms
	* must preserve all bits of static field offsets.
	* @see #getInt(Object, long)
	*/
	public native long staticFieldOffset(Field f);

	/**
	* Report the location of a given static field, in conjunction with {@link
	* #staticFieldBase}.
	* <p>Do not expect to perform any sort of arithmetic on this offset;
	* it is just a cookie which is passed to the unsafe heap memory accessors.
	*
	* <p>Any given field will always have the same offset, and no two distinct
	* fields of the same class will ever have the same offset.
	*
	* <p>As of 1.4.1, offsets for fields are represented as long values,
	* although the Sun JVM does not use the most significant 32 bits.
	* It is hard to imagine a JVM technology which needs more than
	* a few bits to encode an offset within a non-array object,
	* However, for consistency with other methods in this class,
	* this method reports its result as a long value.
	* @see #getInt(Object, long)
	*/
	public native long objectFieldOffset(Field f);

	/**
	* Report the location of a given static field, in conjunction with {@link
	* #staticFieldOffset}.
	* <p>Fetch the base "Object", if any, with which static fields of the
	* given class can be accessed via methods like {@link #getInt(Object,
	* long)}. This value may be null. This value may refer to an object
	* which is a "cookie", not guaranteed to be a real Object, and it should
	* not be used in any way except as argument to the get and put routines in
	* this class.
	*/
	public native Object staticFieldBase(Field f);

	/**
	* Detect if the given class may need to be initialized. This is often
	* needed in conjunction with obtaining the static field base of a
	* class.
	* @return false only if a call to {@code ensureClassInitialized} would have no effect
	*/
	public native boolean shouldBeInitialized(Class<?> c);

	/**
	* Ensure the given class has been initialized. This is often
	* needed in conjunction with obtaining the static field base of a
	* class.
	*/
	public native void ensureClassInitialized(Class<?> c);

	/**
	* Report the offset of the first element in the storage allocation of a
	* given array class. If {@link #arrayIndexScale} returns a non-zero value
	* for the same class, you may use that scale factor, together with this
	* base offset, to form new offsets to access elements of arrays of the
	* given class.
	*
	* @see #getInt(Object, long)
	* @see #putInt(Object, long, int)
	*/
	public native int arrayBaseOffset(Class<?> arrayClass);

	/** The value of {@code arrayBaseOffset(boolean[].class)} */
	public static final int ARRAY_BOOLEAN_BASE_OFFSET
	= theUnsafe.arrayBaseOffset(boolean[].class);

	/** The value of {@code arrayBaseOffset(byte[].class)} */
	public static final int ARRAY_BYTE_BASE_OFFSET
	= theUnsafe.arrayBaseOffset(byte[].class);

	/** The value of {@code arrayBaseOffset(short[].class)} */
	public static final int ARRAY_SHORT_BASE_OFFSET
	= theUnsafe.arrayBaseOffset(short[].class);

	/** The value of {@code arrayBaseOffset(char[].class)} */
	public static final int ARRAY_CHAR_BASE_OFFSET
	= theUnsafe.arrayBaseOffset(char[].class);

	/** The value of {@code arrayBaseOffset(int[].class)} */
	public static final int ARRAY_INT_BASE_OFFSET
	= theUnsafe.arrayBaseOffset(int[].class);

	/** The value of {@code arrayBaseOffset(long[].class)} */
	public static final int ARRAY_LONG_BASE_OFFSET
	= theUnsafe.arrayBaseOffset(long[].class);

	/** The value of {@code arrayBaseOffset(float[].class)} */
	public static final int ARRAY_FLOAT_BASE_OFFSET
	= theUnsafe.arrayBaseOffset(float[].class);

	/** The value of {@code arrayBaseOffset(double[].class)} */
	public static final int ARRAY_DOUBLE_BASE_OFFSET
	= theUnsafe.arrayBaseOffset(double[].class);

	/** The value of {@code arrayBaseOffset(Object[].class)} */
	public static final int ARRAY_OBJECT_BASE_OFFSET
	= theUnsafe.arrayBaseOffset(Object[].class);

	/**
	* Report the scale factor for addressing elements in the storage
	* allocation of a given array class. However, arrays of "narrow" types
	* will generally not work properly with accessors like {@link
	* #getByte(Object, int)}, so the scale factor for such classes is reported
	* as zero.
	*
	* @see #arrayBaseOffset
	* @see #getInt(Object, long)
	* @see #putInt(Object, long, int)
	*/
	public native int arrayIndexScale(Class<?> arrayClass);

	/** The value of {@code arrayIndexScale(boolean[].class)} */
	public static final int ARRAY_BOOLEAN_INDEX_SCALE
	= theUnsafe.arrayIndexScale(boolean[].class);

	/** The value of {@code arrayIndexScale(byte[].class)} */
	public static final int ARRAY_BYTE_INDEX_SCALE
	= theUnsafe.arrayIndexScale(byte[].class);

	/** The value of {@code arrayIndexScale(short[].class)} */
	public static final int ARRAY_SHORT_INDEX_SCALE
	= theUnsafe.arrayIndexScale(short[].class);

	/** The value of {@code arrayIndexScale(char[].class)} */
	public static final int ARRAY_CHAR_INDEX_SCALE
	= theUnsafe.arrayIndexScale(char[].class);

	/** The value of {@code arrayIndexScale(int[].class)} */
	public static final int ARRAY_INT_INDEX_SCALE
	= theUnsafe.arrayIndexScale(int[].class);

	/** The value of {@code arrayIndexScale(long[].class)} */
	public static final int ARRAY_LONG_INDEX_SCALE
	= theUnsafe.arrayIndexScale(long[].class);

	/** The value of {@code arrayIndexScale(float[].class)} */
	public static final int ARRAY_FLOAT_INDEX_SCALE
	= theUnsafe.arrayIndexScale(float[].class);

	/** The value of {@code arrayIndexScale(double[].class)} */
	public static final int ARRAY_DOUBLE_INDEX_SCALE
	= theUnsafe.arrayIndexScale(double[].class);

	/** The value of {@code arrayIndexScale(Object[].class)} */
	public static final int ARRAY_OBJECT_INDEX_SCALE
	= theUnsafe.arrayIndexScale(Object[].class);

	/**
	* Report the size in bytes of a native pointer, as stored via {@link
	* #putAddress}. This value will be either 4 or 8. Note that the sizes of
	* other primitive types (as stored in native memory blocks) is determined
	* fully by their information content.
	*/
	public native int addressSize();

	/** The value of {@code addressSize()} */
	public static final int ADDRESS_SIZE = theUnsafe.addressSize();

	/**
	* Report the size in bytes of a native memory page (whatever that is).
	* This value will always be a power of two.
	*/
	public native int pageSize();


	/// random trusted operations from JNI:

	/**
	* Tell the VM to define a class, without security checks. By default, the
	* class loader and protection domain come from the caller's class.
	*/
	public native Class<?> defineClass(String name, byte[] b, int off, int len,
	ClassLoader loader,
	ProtectionDomain protectionDomain);

	/**
	* Define a class but do not make it known to the class loader or system dictionary.
	* <p>
	* For each CP entry, the corresponding CP patch must either be null or have
	* the a format that matches its tag:
	* <ul>
	* <li>Integer, Long, Float, Double: the corresponding wrapper object type from java.lang
	* <li>Utf8: a string (must have suitable syntax if used as signature or name)
	* <li>Class: any java.lang.Class object
	* <li>String: any object (not just a java.lang.String)
	* <li>InterfaceMethodRef: (NYI) a method handle to invoke on that call site's arguments
	* </ul>
	* @params hostClass context for linkage, access control, protection domain, and class loader
	* @params data bytes of a class file
	* @params cpPatches where non-null entries exist, they replace corresponding CP entries in data
	*/
	public native Class<?> defineAnonymousClass(Class<?> hostClass, byte[] data, Object[] cpPatches);


	/** Allocate an instance but do not run any constructor.
	Initializes the class if it has not yet been. */
	public native Object allocateInstance(Class<?> cls)
	throws InstantiationException;

	/** Lock the object. It must get unlocked via {@link #monitorExit}. */
	@Deprecated
	public native void monitorEnter(Object o);

	/**
	* Unlock the object. It must have been locked via {@link
	* #monitorEnter}.
	*/
	@Deprecated
	public native void monitorExit(Object o);

	/**
	* Tries to lock the object. Returns true or false to indicate
	* whether the lock succeeded. If it did, the object must be
	* unlocked via {@link #monitorExit}.
	*/
	@Deprecated
	public native boolean tryMonitorEnter(Object o);

	/** Throw the exception without telling the verifier. */
	public native void throwException(Throwable ee);


	/**
	* Atomically update Java variable to <tt>x</tt> if it is currently
	* holding <tt>expected</tt>.
	* @return <tt>true</tt> if successful
	*/
	public final native boolean compareAndSwapObject(Object o, long offset,
	Object expected,
	Object x);

	/**
	* Atomically update Java variable to <tt>x</tt> if it is currently
	* holding <tt>expected</tt>.
	* @return <tt>true</tt> if successful
	*/
	public final native boolean compareAndSwapInt(Object o, long offset,
	int expected,
	int x);

	/**
	* Atomically update Java variable to <tt>x</tt> if it is currently
	* holding <tt>expected</tt>.
	* @return <tt>true</tt> if successful
	*/
	public final native boolean compareAndSwapLong(Object o, long offset,
	long expected,
	long x);

	/**
	* Fetches a reference value from a given Java variable, with volatile
	* load semantics. Otherwise identical to {@link #getObject(Object, long)}
	*/
	public native Object getObjectVolatile(Object o, long offset);

	/**
	* Stores a reference value into a given Java variable, with
	* volatile store semantics. Otherwise identical to {@link #putObject(Object, long, Object)}
	*/
	public native void putObjectVolatile(Object o, long offset, Object x);

	/** Volatile version of {@link #getInt(Object, long)} */
	public native int getIntVolatile(Object o, long offset);

	/** Volatile version of {@link #putInt(Object, long, int)} */
	public native void putIntVolatile(Object o, long offset, int x);

	/** Volatile version of {@link #getBoolean(Object, long)} */
	public native boolean getBooleanVolatile(Object o, long offset);

	/** Volatile version of {@link #putBoolean(Object, long, boolean)} */
	public native void putBooleanVolatile(Object o, long offset, boolean x);

	/** Volatile version of {@link #getByte(Object, long)} */
	public native byte getByteVolatile(Object o, long offset);

	/** Volatile version of {@link #putByte(Object, long, byte)} */
	public native void putByteVolatile(Object o, long offset, byte x);

	/** Volatile version of {@link #getShort(Object, long)} */
	public native short getShortVolatile(Object o, long offset);

	/** Volatile version of {@link #putShort(Object, long, short)} */
	public native void putShortVolatile(Object o, long offset, short x);

	/** Volatile version of {@link #getChar(Object, long)} */
	public native char getCharVolatile(Object o, long offset);

	/** Volatile version of {@link #putChar(Object, long, char)} */
	public native void putCharVolatile(Object o, long offset, char x);

	/** Volatile version of {@link #getLong(Object, long)} */
	public native long getLongVolatile(Object o, long offset);

	/** Volatile version of {@link #putLong(Object, long, long)} */
	public native void putLongVolatile(Object o, long offset, long x);

	/** Volatile version of {@link #getFloat(Object, long)} */
	public native float getFloatVolatile(Object o, long offset);

	/** Volatile version of {@link #putFloat(Object, long, float)} */
	public native void putFloatVolatile(Object o, long offset, float x);

	/** Volatile version of {@link #getDouble(Object, long)} */
	public native double getDoubleVolatile(Object o, long offset);

	/** Volatile version of {@link #putDouble(Object, long, double)} */
	public native void putDoubleVolatile(Object o, long offset, double x);

	/**
	* Version of {@link #putObjectVolatile(Object, long, Object)}
	* that does not guarantee immediate visibility of the store to
	* other threads. This method is generally only useful if the
	* underlying field is a Java volatile (or if an array cell, one
	* that is otherwise only accessed using volatile accesses).
	*/
	public native void putOrderedObject(Object o, long offset, Object x);

	/** Ordered/Lazy version of {@link #putIntVolatile(Object, long, int)} */
	public native void putOrderedInt(Object o, long offset, int x);

	/** Ordered/Lazy version of {@link #putLongVolatile(Object, long, long)} */
	public native void putOrderedLong(Object o, long offset, long x);

	/**
	* Unblock the given thread blocked on <tt>park</tt>, or, if it is
	* not blocked, cause the subsequent call to <tt>park</tt> not to
	* block. Note: this operation is "unsafe" solely because the
	* caller must somehow ensure that the thread has not been
	* destroyed. Nothing special is usually required to ensure this
	* when called from Java (in which there will ordinarily be a live
	* reference to the thread) but this is not nearly-automatically
	* so when calling from native code.
	* @param thread the thread to unpark.
	*
	*/
	public native void unpark(Object thread);

	/**
	* Block current thread, returning when a balancing
	* <tt>unpark</tt> occurs, or a balancing <tt>unpark</tt> has
	* already occurred, or the thread is interrupted, or, if not
	* absolute and time is not zero, the given time nanoseconds have
	* elapsed, or if absolute, the given deadline in milliseconds
	* since Epoch has passed, or spuriously (i.e., returning for no
	* "reason"). Note: This operation is in the Unsafe class only
	* because <tt>unpark</tt> is, so it would be strange to place it
	* elsewhere.
	*/
	public native void park(boolean isAbsolute, long time);

	/**
	* Gets the load average in the system run queue assigned
	* to the available processors averaged over various periods of time.
	* This method retrieves the given <tt>nelem</tt> samples and
	* assigns to the elements of the given <tt>loadavg</tt> array.
	* The system imposes a maximum of 3 samples, representing
	* averages over the last 1, 5, and 15 minutes, respectively.
	*
	* @params loadavg an array of double of size nelems
	* @params nelems the number of samples to be retrieved and
	* must be 1 to 3.
	*
	* @return the number of samples actually retrieved; or -1
	* if the load average is unobtainable.
	*/
	public native int getLoadAverage(double[] loadavg, int nelems);

	// The following contain CAS-based Java implementations used on
	// platforms not supporting native instructions

	/**
	* Atomically adds the given value to the current value of a field
	* or array element within the given object <code>o</code>
	* at the given <code>offset</code>.
	*
	* @param o object/array to update the field/element in
	* @param offset field/element offset
	* @param delta the value to add
	* @return the previous value
	* @since 1.8
	*/
	public final int getAndAddInt(Object o, long offset, int delta) {
	int v;
	do {
	v = getIntVolatile(o, offset);
	} while (!compareAndSwapInt(o, offset, v, v + delta));
	return v;
	}

	/**
	* Atomically adds the given value to the current value of a field
	* or array element within the given object <code>o</code>
	* at the given <code>offset</code>.
	*
	* @param o object/array to update the field/element in
	* @param offset field/element offset
	* @param delta the value to add
	* @return the previous value
	* @since 1.8
	*/
	public final long getAndAddLong(Object o, long offset, long delta) {
	long v;
	do {
	v = getLongVolatile(o, offset);
	} while (!compareAndSwapLong(o, offset, v, v + delta));
	return v;
	}

	/**
	* Atomically exchanges the given value with the current value of
	* a field or array element within the given object <code>o</code>
	* at the given <code>offset</code>.
	*
	* @param o object/array to update the field/element in
	* @param offset field/element offset
	* @param newValue new value
	* @return the previous value
	* @since 1.8
	*/
	public final int getAndSetInt(Object o, long offset, int newValue) {
	int v;
	do {
	v = getIntVolatile(o, offset);
	} while (!compareAndSwapInt(o, offset, v, newValue));
	return v;
	}

	/**
	* Atomically exchanges the given value with the current value of
	* a field or array element within the given object <code>o</code>
	* at the given <code>offset</code>.
	*
	* @param o object/array to update the field/element in
	* @param offset field/element offset
	* @param newValue new value
	* @return the previous value
	* @since 1.8
	*/
	public final long getAndSetLong(Object o, long offset, long newValue) {
	long v;
	do {
	v = getLongVolatile(o, offset);
	} while (!compareAndSwapLong(o, offset, v, newValue));
	return v;
	}

	/**
	* Atomically exchanges the given reference value with the current
	* reference value of a field or array element within the given
	* object <code>o</code> at the given <code>offset</code>.
	*
	* @param o object/array to update the field/element in
	* @param offset field/element offset
	* @param newValue new value
	* @return the previous value
	* @since 1.8
	*/
	public final Object getAndSetObject(Object o, long offset, Object newValue) {
	Object v;
	do {
	v = getObjectVolatile(o, offset);
	} while (!compareAndSwapObject(o, offset, v, newValue));
	return v;
	}


	/**
	* Ensures lack of reordering of loads before the fence
	* with loads or stores after the fence.
	* @since 1.8
	*/
	public native void loadFence();

	/**
	* Ensures lack of reordering of stores before the fence
	* with loads or stores after the fence.
	* @since 1.8
	*/
	public native void storeFence();

	/**
	* Ensures lack of reordering of loads or stores before the fence
	* with loads or stores after the fence.
	* @since 1.8
	*/
	public native void fullFence();

	/**
	* Throws IllegalAccessError; for use by the VM.
	* @since 1.8
	*/
	private static void throwIllegalAccessError() {
	throw new IllegalAccessError();
	}

	}

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