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	/*
	* Copyright (c) 2017, 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 java.nio;

	import jdk.internal.util.ArraysSupport;

	/**
	* Mismatch methods for buffers
	*/
	final class BufferMismatch {

	static int mismatch(ByteBuffer a, int aOff, ByteBuffer b, int bOff, int length) {
	int i = 0;
	if (length > 7) {
	if (a.get(aOff) != b.get(bOff))
	return 0;
	i = ArraysSupport.vectorizedMismatch(
	a.base(), a.address + aOff,
	b.base(), b.address + bOff,
	length,
	ArraysSupport.LOG2_ARRAY_BYTE_INDEX_SCALE);
	if (i >= 0) return i;
	i = length - ~i;
	}
	for (; i < length; i++) {
	if (a.get(aOff + i) != b.get(bOff + i))
	return i;
	}
	return -1;
	}

	static int mismatch(CharBuffer a, int aOff, CharBuffer b, int bOff, int length) {
	int i = 0;
	// Ensure only heap or off-heap buffer instances use the
	// vectorized mismatch. If either buffer is a StringCharBuffer
	// (order is null) then the slow path is taken
	if (length > 3 && a.charRegionOrder() == b.charRegionOrder()
	&& a.charRegionOrder() != null && b.charRegionOrder() != null) {
	if (a.get(aOff) != b.get(bOff))
	return 0;
	i = ArraysSupport.vectorizedMismatch(
	a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_CHAR_INDEX_SCALE),
	b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_CHAR_INDEX_SCALE),
	length,
	ArraysSupport.LOG2_ARRAY_CHAR_INDEX_SCALE);
	if (i >= 0) return i;
	i = length - ~i;
	}
	for (; i < length; i++) {
	if (a.get(aOff + i) != b.get(bOff + i))
	return i;
	}
	return -1;
	}

	static int mismatch(ShortBuffer a, int aOff, ShortBuffer b, int bOff, int length) {
	int i = 0;
	if (length > 3 && a.order() == b.order()) {
	if (a.get(aOff) != b.get(bOff))
	return 0;
	i = ArraysSupport.vectorizedMismatch(
	a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_SHORT_INDEX_SCALE),
	b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_SHORT_INDEX_SCALE),
	length,
	ArraysSupport.LOG2_ARRAY_SHORT_INDEX_SCALE);
	if (i >= 0) return i;
	i = length - ~i;
	}
	for (; i < length; i++) {
	if (a.get(aOff + i) != b.get(bOff + i))
	return i;
	}
	return -1;
	}

	static int mismatch(IntBuffer a, int aOff, IntBuffer b, int bOff, int length) {
	int i = 0;
	if (length > 1 && a.order() == b.order()) {
	if (a.get(aOff) != b.get(bOff))
	return 0;
	i = ArraysSupport.vectorizedMismatch(
	a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_INT_INDEX_SCALE),
	b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_INT_INDEX_SCALE),
	length,
	ArraysSupport.LOG2_ARRAY_INT_INDEX_SCALE);
	if (i >= 0) return i;
	i = length - ~i;
	}
	for (; i < length; i++) {
	if (a.get(aOff + i) != b.get(bOff + i))
	return i;
	}
	return -1;
	}

	static int mismatch(FloatBuffer a, int aOff, FloatBuffer b, int bOff, int length) {
	int i = 0;
	if (length > 1 && a.order() == b.order()) {
	if (Float.floatToRawIntBits(a.get(aOff)) == Float.floatToRawIntBits(b.get(bOff))) {
	i = ArraysSupport.vectorizedMismatch(
	a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_FLOAT_INDEX_SCALE),
	b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_FLOAT_INDEX_SCALE),
	length,
	ArraysSupport.LOG2_ARRAY_FLOAT_INDEX_SCALE);
	}
	// Mismatched
	if (i >= 0) {
	// Check if mismatch is not associated with two NaN values; and
	// is not associated with +0 and -0
	float av = a.get(aOff + i);
	float bv = b.get(bOff + i);
	if (av != bv && (!Float.isNaN(av) \|\| !Float.isNaN(bv)))
	return i;

	// Fall back to slow mechanism
	// ISSUE: Consider looping over vectorizedMismatch adjusting ranges
	// However, requires that returned value be relative to input ranges
	i++;
	}
	// Matched
	else {
	i = length - ~i;
	}
	}
	for (; i < length; i++) {
	float av = a.get(aOff + i);
	float bv = b.get(bOff + i);
	if (av != bv && (!Float.isNaN(av) \|\| !Float.isNaN(bv)))
	return i;
	}
	return -1;
	}

	static int mismatch(LongBuffer a, int aOff, LongBuffer b, int bOff, int length) {
	int i = 0;
	if (length > 0 && a.order() == b.order()) {
	if (a.get(aOff) != b.get(bOff))
	return 0;
	i = ArraysSupport.vectorizedMismatch(
	a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_LONG_INDEX_SCALE),
	b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_LONG_INDEX_SCALE),
	length,
	ArraysSupport.LOG2_ARRAY_LONG_INDEX_SCALE);
	return i >= 0 ? i : -1;
	}
	for (; i < length; i++) {
	if (a.get(aOff + i) != b.get(bOff + i))
	return i;
	}
	return -1;
	}

	static int mismatch(DoubleBuffer a, int aOff, DoubleBuffer b, int bOff, int length) {
	int i = 0;
	if (length > 0 && a.order() == b.order()) {
	if (Double.doubleToRawLongBits(a.get(aOff)) == Double.doubleToRawLongBits(b.get(bOff))) {
	i = ArraysSupport.vectorizedMismatch(
	a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_DOUBLE_INDEX_SCALE),
	b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_DOUBLE_INDEX_SCALE),
	length,
	ArraysSupport.LOG2_ARRAY_DOUBLE_INDEX_SCALE);
	}
	// Mismatched
	if (i >= 0) {
	// Check if mismatch is not associated with two NaN values; and
	// is not associated with +0 and -0
	double av = a.get(aOff + i);
	double bv = b.get(bOff + i);
	if (av != bv && (!Double.isNaN(av) \|\| !Double.isNaN(bv)))
	return i;

	// Fall back to slow mechanism
	// ISSUE: Consider looping over vectorizedMismatch adjusting ranges
	// However, requires that returned value be relative to input ranges
	i++;
	}
	// Matched
	else {
	return -1;
	}
	}
	for (; i < length; i++) {
	double av = a.get(aOff + i);
	double bv = b.get(bOff + i);
	if (av != bv && (!Double.isNaN(av) \|\| !Double.isNaN(bv)))
	return i;
	}
	return -1;
	}
	}

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