php-src/Zend/zend_sort.c
2017-07-04 18:12:45 +02:00

386 lines
11 KiB
C

/*
+----------------------------------------------------------------------+
| Zend Engine |
+----------------------------------------------------------------------+
| Copyright (c) 1998-2017 Zend Technologies Ltd. (http://www.zend.com) |
+----------------------------------------------------------------------+
| This source file is subject to version 2.00 of the Zend license, |
| that is bundled with this package in the file LICENSE, and is |
| available through the world-wide-web at the following url: |
| http://www.zend.com/license/2_00.txt. |
| If you did not receive a copy of the Zend license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@zend.com so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Authors: Xinchen Hui <laruence@php.net> |
| Sterling Hughes <sterling@php.net> |
+----------------------------------------------------------------------+
*/
/* $Id$ */
#include "zend.h"
#include "zend_sort.h"
#include <limits.h>
#define QSORT_STACK_SIZE (sizeof(size_t) * CHAR_BIT)
ZEND_API void zend_qsort(void *base, size_t nmemb, size_t siz, compare_func_t compare, swap_func_t swp) /* {{{ */
{
void *begin_stack[QSORT_STACK_SIZE];
void *end_stack[QSORT_STACK_SIZE];
register char *begin;
register char *end;
register char *seg1;
register char *seg2;
register char *seg2p;
register int loop;
size_t offset;
begin_stack[0] = (char *) base;
end_stack[0] = (char *) base + ((nmemb - 1) * siz);
for (loop = 0; loop >= 0; --loop) {
begin = begin_stack[loop];
end = end_stack[loop];
while (begin < end) {
offset = (end - begin) >> Z_L(1);
swp(begin, begin + (offset - (offset % siz)));
seg1 = begin + siz;
seg2 = end;
while (1) {
for (; seg1 < seg2 && compare(begin, seg1) > 0;
seg1 += siz);
for (; seg2 >= seg1 && compare(seg2, begin) > 0;
seg2 -= siz);
if (seg1 >= seg2)
break;
swp(seg1, seg2);
seg1 += siz;
seg2 -= siz;
}
swp(begin, seg2);
seg2p = seg2;
if ((seg2p - begin) <= (end - seg2p)) {
if ((seg2p + siz) < end) {
begin_stack[loop] = seg2p + siz;
end_stack[loop++] = end;
}
end = seg2p - siz;
}
else {
if ((seg2p - siz) > begin) {
begin_stack[loop] = begin;
end_stack[loop++] = seg2p - siz;
}
begin = seg2p + siz;
}
}
}
}
/* }}} */
static inline void zend_sort_2(void *a, void *b, compare_func_t cmp, swap_func_t swp) /* {{{ */ {
if (cmp(a, b) > 0) {
swp(a, b);
}
}
/* }}} */
static inline void zend_sort_3(void *a, void *b, void *c, compare_func_t cmp, swap_func_t swp) /* {{{ */ {
if (!(cmp(a, b) > 0)) {
if (!(cmp(b, c) > 0)) {
return;
}
swp(b, c);
if (cmp(a, b) > 0) {
swp(a, b);
}
return;
}
if (!(cmp(c, b) > 0)) {
swp(a, c);
return;
}
swp(a, b);
if (cmp(b, c) > 0) {
swp(b, c);
}
}
/* }}} */
static void zend_sort_4(void *a, void *b, void *c, void *d, compare_func_t cmp, swap_func_t swp) /* {{{ */ {
zend_sort_3(a, b, c, cmp, swp);
if (cmp(c, d) > 0) {
swp(c, d);
if (cmp(b, c) > 0) {
swp(b, c);
if (cmp(a, b) > 0) {
swp(a, b);
}
}
}
}
/* }}} */
static void zend_sort_5(void *a, void *b, void *c, void *d, void *e, compare_func_t cmp, swap_func_t swp) /* {{{ */ {
zend_sort_4(a, b, c, d, cmp, swp);
if (cmp(d, e) > 0) {
swp(d, e);
if (cmp(c, d) > 0) {
swp(c, d);
if (cmp(b, c) > 0) {
swp(b, c);
if (cmp(a, b) > 0) {
swp(a, b);
}
}
}
}
}
/* }}} */
ZEND_API void zend_insert_sort(void *base, size_t nmemb, size_t siz, compare_func_t cmp, swap_func_t swp) /* {{{ */{
switch (nmemb) {
case 0:
case 1:
break;
case 2:
zend_sort_2(base, (char *)base + siz, cmp, swp);
break;
case 3:
zend_sort_3(base, (char *)base + siz, (char *)base + siz + siz, cmp, swp);
break;
case 4:
{
size_t siz2 = siz + siz;
zend_sort_4(base, (char *)base + siz, (char *)base + siz2, (char *)base + siz + siz2, cmp, swp);
}
break;
case 5:
{
size_t siz2 = siz + siz;
zend_sort_5(base, (char *)base + siz, (char *)base + siz2, (char *)base + siz + siz2, (char *)base + siz2 + siz2, cmp, swp);
}
break;
default:
{
char *i, *j, *k;
char *start = (char *)base;
char *end = start + (nmemb * siz);
size_t siz2= siz + siz;
char *sentry = start + (6 * siz);
for (i = start + siz; i < sentry; i += siz) {
j = i - siz;
if (!(cmp(j, i) > 0)) {
continue;
}
while (j != start) {
j -= siz;
if (!(cmp(j, i) > 0)) {
j += siz;
break;
}
}
for (k = i; k > j; k -= siz) {
swp(k, k - siz);
}
}
for (i = sentry; i < end; i += siz) {
j = i - siz;
if (!(cmp(j, i) > 0)) {
continue;
}
do {
j -= siz2;
if (!(cmp(j, i) > 0)) {
j += siz;
if (!(cmp(j, i) > 0)) {
j += siz;
}
break;
}
if (j == start) {
break;
}
if (j == start + siz) {
j -= siz;
if (cmp(i, j) > 0) {
j += siz;
}
break;
}
} while (1);
for (k = i; k > j; k -= siz) {
swp(k, k - siz);
}
}
}
break;
}
}
/* }}} */
/* {{{ ZEND_API void zend_sort(void *base, size_t nmemb, size_t siz, compare_func_t cmp, swap_func_t swp)
*
* Derived from LLVM's libc++ implementation of std::sort.
*
* ===========================================================================
* libc++ License
* ===========================================================================
*
* The libc++ library is dual licensed under both the University of Illinois
* "BSD-Like" license and the MIT license. As a user of this code you may
* choose to use it under either license. As a contributor, you agree to allow
* your code to be used under both.
*
* Full text of the relevant licenses is included below.
*
* ===========================================================================
*
* University of Illinois/NCSA
* Open Source License
*
* Copyright (c) 2009-2012 by the contributors listed at
* http://llvm.org/svn/llvm-project/libcxx/trunk/CREDITS.TXT
*
* All rights reserved.
*
* Developed by:
*
* LLVM Team
*
* University of Illinois at Urbana-Champaign
*
* http://llvm.org
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal with the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimers.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimers in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the names of the LLVM Team, University of Illinois at
* Urbana-Champaign, nor the names of its contributors may be used to
* endorse or promote products derived from this Software without
* specific prior written permission.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* WITH THE SOFTWARE.
*
* ===========================================================================
*
* Copyright (c) 2009-2012 by the contributors listed at
* http://llvm.org/svn/llvm-project/libcxx/trunk/CREDITS.TXT
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
ZEND_API void zend_sort(void *base, size_t nmemb, size_t siz, compare_func_t cmp, swap_func_t swp)
{
while (1) {
if (nmemb <= 16) {
zend_insert_sort(base, nmemb, siz, cmp, swp);
return;
} else {
char *i, *j;
char *start = (char *)base;
char *end = start + (nmemb * siz);
size_t offset = (nmemb >> Z_L(1));
char *pivot = start + (offset * siz);
if ((nmemb >> Z_L(10))) {
size_t delta = (offset >> Z_L(1)) * siz;
zend_sort_5(start, start + delta, pivot, pivot + delta, end - siz, cmp, swp);
} else {
zend_sort_3(start, pivot, end - siz, cmp, swp);
}
swp(start + siz, pivot);
pivot = start + siz;
i = pivot + siz;
j = end - siz;
while (1) {
while (cmp(pivot, i) > 0) {
i += siz;
if (UNEXPECTED(i == j)) {
goto done;
}
}
j -= siz;
if (UNEXPECTED(j == i)) {
goto done;
}
while (cmp(j, pivot) > 0) {
j -= siz;
if (UNEXPECTED(j == i)) {
goto done;
}
}
swp(i, j);
i += siz;
if (UNEXPECTED(i == j)) {
goto done;
}
}
done:
swp(pivot, i - siz);
if ((i - siz) - start < end - i) {
zend_sort(start, (i - start)/siz - 1, siz, cmp, swp);
base = i;
nmemb = (end - i)/siz;
} else {
zend_sort(i, (end - i)/siz, siz, cmp, swp);
nmemb = (i - start)/siz - 1;
}
}
}
}
/* }}} */
/*
* Local Variables:
* c-basic-offset: 4
* tab-width: 4
* End:
* vim600: sw=4 ts=4 fdm=marker
* vim<600: sw=4 ts=4
*/