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	/*
	* Copyright (c) 2006, 2016, 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.security.provider;

	import static java.lang.Integer.reverseBytes;
	import static java.lang.Long.reverseBytes;

	import java.nio.ByteOrder;

	import sun.misc.Unsafe;

	/**
	* Optimized methods for converting between byte[] and int[]/long[], both for
	* big endian and little endian byte orders.
	*
	* Currently, it includes a default code path plus two optimized code paths.
	* One is for little endian architectures that support full speed int/long
	* access at unaligned addresses (i.e. x86/amd64). The second is for big endian
	* architectures (that only support correctly aligned access), such as SPARC.
	* These are the only platforms we currently support, but other optimized
	* variants could be added as needed.
	*
	* NOTE that ArrayIndexOutOfBoundsException will be thrown if the bounds checks
	* failed.
	*
	* This class may also be helpful in improving the performance of the
	* crypto code in the SunJCE provider. However, for now it is only accessible by
	* the message digest implementation in the SUN provider.
	*
	* @since 1.6
	* @author Andreas Sterbenz
	*/
	final class ByteArrayAccess {

	private ByteArrayAccess() {
	// empty
	}

	private static final Unsafe unsafe = Unsafe.getUnsafe();

	// whether to use the optimized path for little endian platforms that
	// support full speed unaligned memory access.
	private static final boolean littleEndianUnaligned;

	// whether to use the optimzied path for big endian platforms that
	// support only correctly aligned full speed memory access.
	// (Note that on SPARC unaligned memory access is possible, but it is
	// implemented using a software trap and therefore very slow)
	private static final boolean bigEndian;

	private final static int byteArrayOfs = unsafe.arrayBaseOffset(byte[].class);

	static {
	boolean scaleOK = ((unsafe.arrayIndexScale(byte[].class) == 1)
	&& (unsafe.arrayIndexScale(int[].class) == 4)
	&& (unsafe.arrayIndexScale(long[].class) == 8)
	&& ((byteArrayOfs & 3) == 0));

	ByteOrder byteOrder = ByteOrder.nativeOrder();
	littleEndianUnaligned =
	scaleOK && unaligned() && (byteOrder == ByteOrder.LITTLE_ENDIAN);
	bigEndian =
	scaleOK && (byteOrder == ByteOrder.BIG_ENDIAN);
	}

	// Return whether this platform supports full speed int/long memory access
	// at unaligned addresses.
	// This code was copied from java.nio.Bits because there is no equivalent
	// public API.
	private static boolean unaligned() {
	String arch = java.security.AccessController.doPrivileged
	(new sun.security.action.GetPropertyAction("os.arch", ""));
	return arch.equals("i386") \|\| arch.equals("x86") \|\| arch.equals("amd64")
	\|\| arch.equals("x86_64") \|\| arch.equals("ppc64") \|\| arch.equals("ppc64le")
	\|\| arch.equals("aarch64");
	}

	/**
	* byte[] to int[] conversion, little endian byte order.
	*/
	static void b2iLittle(byte[] in, int inOfs, int[] out, int outOfs, int len) {
	if ((inOfs < 0) \|\| ((in.length - inOfs) < len) \|\|
	(outOfs < 0) \|\| ((out.length - outOfs) < len/4)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	if (littleEndianUnaligned) {
	inOfs += byteArrayOfs;
	len += inOfs;
	while (inOfs < len) {
	out[outOfs++] = unsafe.getInt(in, (long)inOfs);
	inOfs += 4;
	}
	} else if (bigEndian && ((inOfs & 3) == 0)) {
	inOfs += byteArrayOfs;
	len += inOfs;
	while (inOfs < len) {
	out[outOfs++] = reverseBytes(unsafe.getInt(in, (long)inOfs));
	inOfs += 4;
	}
	} else {
	len += inOfs;
	while (inOfs < len) {
	out[outOfs++] = ((in[inOfs ] & 0xff) )
	\| ((in[inOfs + 1] & 0xff) << 8)
	\| ((in[inOfs + 2] & 0xff) << 16)
	\| ((in[inOfs + 3] ) << 24);
	inOfs += 4;
	}
	}
	}

	// Special optimization of b2iLittle(in, inOfs, out, 0, 64)
	static void b2iLittle64(byte[] in, int inOfs, int[] out) {
	if ((inOfs < 0) \|\| ((in.length - inOfs) < 64) \|\|
	(out.length < 16)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	if (littleEndianUnaligned) {
	inOfs += byteArrayOfs;
	out[ 0] = unsafe.getInt(in, (long)(inOfs ));
	out[ 1] = unsafe.getInt(in, (long)(inOfs + 4));
	out[ 2] = unsafe.getInt(in, (long)(inOfs + 8));
	out[ 3] = unsafe.getInt(in, (long)(inOfs + 12));
	out[ 4] = unsafe.getInt(in, (long)(inOfs + 16));
	out[ 5] = unsafe.getInt(in, (long)(inOfs + 20));
	out[ 6] = unsafe.getInt(in, (long)(inOfs + 24));
	out[ 7] = unsafe.getInt(in, (long)(inOfs + 28));
	out[ 8] = unsafe.getInt(in, (long)(inOfs + 32));
	out[ 9] = unsafe.getInt(in, (long)(inOfs + 36));
	out[10] = unsafe.getInt(in, (long)(inOfs + 40));
	out[11] = unsafe.getInt(in, (long)(inOfs + 44));
	out[12] = unsafe.getInt(in, (long)(inOfs + 48));
	out[13] = unsafe.getInt(in, (long)(inOfs + 52));
	out[14] = unsafe.getInt(in, (long)(inOfs + 56));
	out[15] = unsafe.getInt(in, (long)(inOfs + 60));
	} else if (bigEndian && ((inOfs & 3) == 0)) {
	inOfs += byteArrayOfs;
	out[ 0] = reverseBytes(unsafe.getInt(in, (long)(inOfs )));
	out[ 1] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 4)));
	out[ 2] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 8)));
	out[ 3] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 12)));
	out[ 4] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 16)));
	out[ 5] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 20)));
	out[ 6] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 24)));
	out[ 7] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 28)));
	out[ 8] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 32)));
	out[ 9] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 36)));
	out[10] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 40)));
	out[11] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 44)));
	out[12] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 48)));
	out[13] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 52)));
	out[14] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 56)));
	out[15] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 60)));
	} else {
	b2iLittle(in, inOfs, out, 0, 64);
	}
	}

	/**
	* int[] to byte[] conversion, little endian byte order.
	*/
	static void i2bLittle(int[] in, int inOfs, byte[] out, int outOfs, int len) {
	if ((inOfs < 0) \|\| ((in.length - inOfs) < len/4) \|\|
	(outOfs < 0) \|\| ((out.length - outOfs) < len)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	if (littleEndianUnaligned) {
	outOfs += byteArrayOfs;
	len += outOfs;
	while (outOfs < len) {
	unsafe.putInt(out, (long)outOfs, in[inOfs++]);
	outOfs += 4;
	}
	} else if (bigEndian && ((outOfs & 3) == 0)) {
	outOfs += byteArrayOfs;
	len += outOfs;
	while (outOfs < len) {
	unsafe.putInt(out, (long)outOfs, reverseBytes(in[inOfs++]));
	outOfs += 4;
	}
	} else {
	len += outOfs;
	while (outOfs < len) {
	int i = in[inOfs++];
	out[outOfs++] = (byte)(i );
	out[outOfs++] = (byte)(i >> 8);
	out[outOfs++] = (byte)(i >> 16);
	out[outOfs++] = (byte)(i >> 24);
	}
	}
	}

	// Store one 32-bit value into out[outOfs..outOfs+3] in little endian order.
	static void i2bLittle4(int val, byte[] out, int outOfs) {
	if ((outOfs < 0) \|\| ((out.length - outOfs) < 4)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	if (littleEndianUnaligned) {
	unsafe.putInt(out, (long)(byteArrayOfs + outOfs), val);
	} else if (bigEndian && ((outOfs & 3) == 0)) {
	unsafe.putInt(out, (long)(byteArrayOfs + outOfs), reverseBytes(val));
	} else {
	out[outOfs ] = (byte)(val );
	out[outOfs + 1] = (byte)(val >> 8);
	out[outOfs + 2] = (byte)(val >> 16);
	out[outOfs + 3] = (byte)(val >> 24);
	}
	}

	/**
	* byte[] to int[] conversion, big endian byte order.
	*/
	static void b2iBig(byte[] in, int inOfs, int[] out, int outOfs, int len) {
	if ((inOfs < 0) \|\| ((in.length - inOfs) < len) \|\|
	(outOfs < 0) \|\| ((out.length - outOfs) < len/4)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	if (littleEndianUnaligned) {
	inOfs += byteArrayOfs;
	len += inOfs;
	while (inOfs < len) {
	out[outOfs++] = reverseBytes(unsafe.getInt(in, (long)inOfs));
	inOfs += 4;
	}
	} else if (bigEndian && ((inOfs & 3) == 0)) {
	inOfs += byteArrayOfs;
	len += inOfs;
	while (inOfs < len) {
	out[outOfs++] = unsafe.getInt(in, (long)inOfs);
	inOfs += 4;
	}
	} else {
	len += inOfs;
	while (inOfs < len) {
	out[outOfs++] = ((in[inOfs + 3] & 0xff) )
	\| ((in[inOfs + 2] & 0xff) << 8)
	\| ((in[inOfs + 1] & 0xff) << 16)
	\| ((in[inOfs ] ) << 24);
	inOfs += 4;
	}
	}
	}

	// Special optimization of b2iBig(in, inOfs, out, 0, 64)
	static void b2iBig64(byte[] in, int inOfs, int[] out) {
	if ((inOfs < 0) \|\| ((in.length - inOfs) < 64) \|\|
	(out.length < 16)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	if (littleEndianUnaligned) {
	inOfs += byteArrayOfs;
	out[ 0] = reverseBytes(unsafe.getInt(in, (long)(inOfs )));
	out[ 1] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 4)));
	out[ 2] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 8)));
	out[ 3] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 12)));
	out[ 4] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 16)));
	out[ 5] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 20)));
	out[ 6] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 24)));
	out[ 7] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 28)));
	out[ 8] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 32)));
	out[ 9] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 36)));
	out[10] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 40)));
	out[11] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 44)));
	out[12] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 48)));
	out[13] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 52)));
	out[14] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 56)));
	out[15] = reverseBytes(unsafe.getInt(in, (long)(inOfs + 60)));
	} else if (bigEndian && ((inOfs & 3) == 0)) {
	inOfs += byteArrayOfs;
	out[ 0] = unsafe.getInt(in, (long)(inOfs ));
	out[ 1] = unsafe.getInt(in, (long)(inOfs + 4));
	out[ 2] = unsafe.getInt(in, (long)(inOfs + 8));
	out[ 3] = unsafe.getInt(in, (long)(inOfs + 12));
	out[ 4] = unsafe.getInt(in, (long)(inOfs + 16));
	out[ 5] = unsafe.getInt(in, (long)(inOfs + 20));
	out[ 6] = unsafe.getInt(in, (long)(inOfs + 24));
	out[ 7] = unsafe.getInt(in, (long)(inOfs + 28));
	out[ 8] = unsafe.getInt(in, (long)(inOfs + 32));
	out[ 9] = unsafe.getInt(in, (long)(inOfs + 36));
	out[10] = unsafe.getInt(in, (long)(inOfs + 40));
	out[11] = unsafe.getInt(in, (long)(inOfs + 44));
	out[12] = unsafe.getInt(in, (long)(inOfs + 48));
	out[13] = unsafe.getInt(in, (long)(inOfs + 52));
	out[14] = unsafe.getInt(in, (long)(inOfs + 56));
	out[15] = unsafe.getInt(in, (long)(inOfs + 60));
	} else {
	b2iBig(in, inOfs, out, 0, 64);
	}
	}

	/**
	* int[] to byte[] conversion, big endian byte order.
	*/
	static void i2bBig(int[] in, int inOfs, byte[] out, int outOfs, int len) {
	if ((inOfs < 0) \|\| ((in.length - inOfs) < len/4) \|\|
	(outOfs < 0) \|\| ((out.length - outOfs) < len)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	if (littleEndianUnaligned) {
	outOfs += byteArrayOfs;
	len += outOfs;
	while (outOfs < len) {
	unsafe.putInt(out, (long)outOfs, reverseBytes(in[inOfs++]));
	outOfs += 4;
	}
	} else if (bigEndian && ((outOfs & 3) == 0)) {
	outOfs += byteArrayOfs;
	len += outOfs;
	while (outOfs < len) {
	unsafe.putInt(out, (long)outOfs, in[inOfs++]);
	outOfs += 4;
	}
	} else {
	len += outOfs;
	while (outOfs < len) {
	int i = in[inOfs++];
	out[outOfs++] = (byte)(i >> 24);
	out[outOfs++] = (byte)(i >> 16);
	out[outOfs++] = (byte)(i >> 8);
	out[outOfs++] = (byte)(i );
	}
	}
	}

	// Store one 32-bit value into out[outOfs..outOfs+3] in big endian order.
	static void i2bBig4(int val, byte[] out, int outOfs) {
	if ((outOfs < 0) \|\| ((out.length - outOfs) < 4)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	if (littleEndianUnaligned) {
	unsafe.putInt(out, (long)(byteArrayOfs + outOfs), reverseBytes(val));
	} else if (bigEndian && ((outOfs & 3) == 0)) {
	unsafe.putInt(out, (long)(byteArrayOfs + outOfs), val);
	} else {
	out[outOfs ] = (byte)(val >> 24);
	out[outOfs + 1] = (byte)(val >> 16);
	out[outOfs + 2] = (byte)(val >> 8);
	out[outOfs + 3] = (byte)(val );
	}
	}

	/**
	* byte[] to long[] conversion, big endian byte order.
	*/
	static void b2lBig(byte[] in, int inOfs, long[] out, int outOfs, int len) {
	if ((inOfs < 0) \|\| ((in.length - inOfs) < len) \|\|
	(outOfs < 0) \|\| ((out.length - outOfs) < len/8)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	if (littleEndianUnaligned) {
	inOfs += byteArrayOfs;
	len += inOfs;
	while (inOfs < len) {
	out[outOfs++] = reverseBytes(unsafe.getLong(in, (long)inOfs));
	inOfs += 8;
	}
	} else if (bigEndian && ((inOfs & 3) == 0)) {
	// In the current HotSpot memory layout, the first element of a
	// byte[] is only 32-bit aligned, not 64-bit.
	// That means we could use getLong() only for offset 4, 12, etc.,
	// which would rarely occur in practice. Instead, we use an
	// optimization that uses getInt() so that it works for offset 0.
	inOfs += byteArrayOfs;
	len += inOfs;
	while (inOfs < len) {
	out[outOfs++] =
	((long)unsafe.getInt(in, (long)inOfs) << 32)
	\| (unsafe.getInt(in, (long)(inOfs + 4)) & 0xffffffffL);
	inOfs += 8;
	}
	} else {
	len += inOfs;
	while (inOfs < len) {
	int i1 = ((in[inOfs + 3] & 0xff) )
	\| ((in[inOfs + 2] & 0xff) << 8)
	\| ((in[inOfs + 1] & 0xff) << 16)
	\| ((in[inOfs ] ) << 24);
	inOfs += 4;
	int i2 = ((in[inOfs + 3] & 0xff) )
	\| ((in[inOfs + 2] & 0xff) << 8)
	\| ((in[inOfs + 1] & 0xff) << 16)
	\| ((in[inOfs ] ) << 24);
	out[outOfs++] = ((long)i1 << 32) \| (i2 & 0xffffffffL);
	inOfs += 4;
	}
	}
	}

	// Special optimization of b2lBig(in, inOfs, out, 0, 128)
	static void b2lBig128(byte[] in, int inOfs, long[] out) {
	if ((inOfs < 0) \|\| ((in.length - inOfs) < 128) \|\|
	(out.length < 16)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	if (littleEndianUnaligned) {
	inOfs += byteArrayOfs;
	out[ 0] = reverseBytes(unsafe.getLong(in, (long)(inOfs )));
	out[ 1] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 8)));
	out[ 2] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 16)));
	out[ 3] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 24)));
	out[ 4] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 32)));
	out[ 5] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 40)));
	out[ 6] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 48)));
	out[ 7] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 56)));
	out[ 8] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 64)));
	out[ 9] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 72)));
	out[10] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 80)));
	out[11] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 88)));
	out[12] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 96)));
	out[13] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 104)));
	out[14] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 112)));
	out[15] = reverseBytes(unsafe.getLong(in, (long)(inOfs + 120)));
	} else {
	// no optimization for big endian, see comments in b2lBig
	b2lBig(in, inOfs, out, 0, 128);
	}
	}

	/**
	* long[] to byte[] conversion, big endian byte order.
	*/
	static void l2bBig(long[] in, int inOfs, byte[] out, int outOfs, int len) {
	if ((inOfs < 0) \|\| ((in.length - inOfs) < len/8) \|\|
	(outOfs < 0) \|\| ((out.length - outOfs) < len)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	len += outOfs;
	while (outOfs < len) {
	long i = in[inOfs++];
	out[outOfs++] = (byte)(i >> 56);
	out[outOfs++] = (byte)(i >> 48);
	out[outOfs++] = (byte)(i >> 40);
	out[outOfs++] = (byte)(i >> 32);
	out[outOfs++] = (byte)(i >> 24);
	out[outOfs++] = (byte)(i >> 16);
	out[outOfs++] = (byte)(i >> 8);
	out[outOfs++] = (byte)(i );
	}
	}
	}

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