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mirror of https://github.com/php/php-src.git synced 2026-03-24 00:02:20 +01:00

Optimize pack()

Instead of using lookup tables, we can use a combination of shifts and
byte swapping to achieve the same thing in less cycles and with less
code.

Benchmark files
---------------

pack1.php:
```php
for ($i = 0; $i < 10_000_000; ++$i) {
    pack("J", 0x7FFFFFFFFFFFFFFF);
}
```

pack2.php:
```php
for ($i = 0; $i < 4000000; ++$i) {
    pack("nvc*", 0x1234, 0x5678, 65, 66);
}
```

On an i7-4790:
```
Benchmark 1: ./sapi/cli/php pack1.php
  Time (mean ± σ):     408.8 ms ±   3.4 ms    [User: 406.1 ms, System: 1.6 ms]
  Range (min … max):   403.6 ms … 413.6 ms    10 runs

Benchmark 2: ./sapi/cli/php_old pack1.php
  Time (mean ± σ):     451.7 ms ±   7.7 ms    [User: 448.5 ms, System: 2.0 ms]
  Range (min … max):   442.8 ms … 461.2 ms    10 runs

Summary
  ./sapi/cli/php pack1.php ran
    1.11 ± 0.02 times faster than ./sapi/cli/php_old pack1.php

Benchmark 1: ./sapi/cli/php pack2.php
  Time (mean ± σ):     239.3 ms ±   6.0 ms    [User: 236.2 ms, System: 2.3 ms]
  Range (min … max):   233.2 ms … 256.8 ms    12 runs

Benchmark 2: ./sapi/cli/php_old pack2.php
  Time (mean ± σ):     271.9 ms ±   3.3 ms    [User: 269.7 ms, System: 1.3 ms]
  Range (min … max):   267.4 ms … 279.0 ms    11 runs

Summary
  ./sapi/cli/php pack2.php ran
    1.14 ± 0.03 times faster than ./sapi/cli/php_old pack2.php
```

On an i7-1185G7:
```
Benchmark 1: ./sapi/cli/php pack1.php
  Time (mean ± σ):     263.7 ms ±   1.8 ms    [User: 262.6 ms, System: 0.9 ms]
  Range (min … max):   261.5 ms … 268.2 ms    11 runs

Benchmark 2: ./sapi/cli/php_old pack1.php
  Time (mean ± σ):     303.3 ms ±   6.5 ms    [User: 300.7 ms, System: 2.3 ms]
  Range (min … max):   297.4 ms … 318.1 ms    10 runs

Summary
  ./sapi/cli/php pack1.php ran
    1.15 ± 0.03 times faster than ./sapi/cli/php_old pack1.php

Benchmark 1: ./sapi/cli/php pack2.php
  Time (mean ± σ):     156.7 ms ±   2.9 ms    [User: 154.7 ms, System: 1.7 ms]
  Range (min … max):   151.6 ms … 164.7 ms    19 runs

Benchmark 2: ./sapi/cli/php_old pack2.php
  Time (mean ± σ):     174.6 ms ±   3.3 ms    [User: 171.9 ms, System: 2.3 ms]
  Range (min … max):   170.7 ms … 180.4 ms    17 runs

Summary
  ./sapi/cli/php pack2.php ran
    1.11 ± 0.03 times faster than ./sapi/cli/php_old pack2.php
```

Closes GH-18524.

Co-authored-by: divinity76 <divinity76@gmail.com>
This commit is contained in:
Niels Dossche
2025-05-08 23:13:32 +02:00
parent 45215d0e78
commit 6cc21c4ee6
6 changed files with 47 additions and 200 deletions

3
NEWS
View File

@@ -2,6 +2,9 @@ PHP NEWS
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
?? ??? ????, PHP 8.5.0alpha2
- Standard:
. Optimized pack(). (nielsdos, divinity76)
- URI:
. Return the singleton UrlValidationErrorType instances from Uri\WhatWg\Url
instead of creating new objects that are different from the singleton.

View File

@@ -619,6 +619,7 @@ PHP 8.5 UPGRADE NOTES
. Improved performance of urlencode() and rawurlencode().
. Improved unpack() performance with nameless repetitions by avoiding
creating temporary strings and reparsing them.
. Improved pack() performance.
- XMLReader:
. Improved property access performance.

View File

@@ -299,7 +299,6 @@ PHP_MINIT_FUNCTION(basic) /* {{{ */
BASIC_MINIT_SUBMODULE(var)
BASIC_MINIT_SUBMODULE(file)
BASIC_MINIT_SUBMODULE(pack)
BASIC_MINIT_SUBMODULE(browscap)
BASIC_MINIT_SUBMODULE(standard_filters)
BASIC_MINIT_SUBMODULE(user_filters)

View File

@@ -19,7 +19,6 @@
#include <stdlib.h>
#include <errno.h>
#include <sys/types.h>
#include "pack.h"
#define INC_OUTPUTPOS(a,b) \
if ((a) < 0 || ((INT_MAX - outputpos)/((int)b)) < (a)) { \
@@ -30,10 +29,23 @@
} \
outputpos += (a)*(b);
typedef enum {
PHP_LITTLE_ENDIAN,
PHP_BIG_ENDIAN,
} php_pack_endianness;
#ifdef WORDS_BIGENDIAN
#define MACHINE_LITTLE_ENDIAN 0
# define MACHINE_LITTLE_ENDIAN 0
# define PHP_MACHINE_ENDIAN PHP_BIG_ENDIAN
#else
#define MACHINE_LITTLE_ENDIAN 1
# define MACHINE_LITTLE_ENDIAN 1
# define PHP_MACHINE_ENDIAN PHP_LITTLE_ENDIAN
#endif
#ifdef ZEND_ENABLE_ZVAL_LONG64
# define PHP_LONG_BSWAP(u) ZEND_BYTES_SWAP64(u)
#else
# define PHP_LONG_BSWAP(u) ZEND_BYTES_SWAP32(u)
#endif
typedef ZEND_SET_ALIGNED(1, uint16_t unaligned_uint16_t);
@@ -42,41 +54,23 @@ typedef ZEND_SET_ALIGNED(1, uint64_t unaligned_uint64_t);
typedef ZEND_SET_ALIGNED(1, unsigned int unaligned_uint);
typedef ZEND_SET_ALIGNED(1, int unaligned_int);
/* Mapping of byte from char (8bit) to long for machine endian */
static int byte_map[1];
/* Mappings of bytes from int (machine dependent) to int for machine endian */
static int int_map[sizeof(int)];
/* Mappings of bytes from shorts (16bit) for all endian environments */
static int machine_endian_short_map[2];
static int big_endian_short_map[2];
static int little_endian_short_map[2];
/* Mappings of bytes from longs (32bit) for all endian environments */
static int machine_endian_long_map[4];
static int big_endian_long_map[4];
static int little_endian_long_map[4];
#if SIZEOF_ZEND_LONG > 4
/* Mappings of bytes from quads (64bit) for all endian environments */
static int machine_endian_longlong_map[8];
static int big_endian_longlong_map[8];
static int little_endian_longlong_map[8];
#endif
/* {{{ php_pack */
static void php_pack(zval *val, size_t size, int *map, char *output)
static void php_pack(const zval *val, size_t size, php_pack_endianness endianness, char *output)
{
size_t i;
char *v;
zend_ulong zl = zval_get_long(val);
convert_to_long(val);
v = (char *) &Z_LVAL_P(val);
for (i = 0; i < size; i++) {
*output++ = v[map[i]];
if ((endianness == PHP_LITTLE_ENDIAN) != MACHINE_LITTLE_ENDIAN) {
zl = PHP_LONG_BSWAP(zl);
#if MACHINE_LITTLE_ENDIAN
zl >>= (sizeof(zl) - size) * 8;
#endif
} else {
#if !MACHINE_LITTLE_ENDIAN
zl <<= (sizeof(zl) - size) * 8;
#endif
}
memcpy(output, (const char *) &zl, size);
}
/* }}} */
@@ -88,10 +82,7 @@ ZEND_ATTRIBUTE_CONST static inline uint16_t php_pack_reverse_int16(uint16_t arg)
/* {{{ php_pack_reverse_int32 */
ZEND_ATTRIBUTE_CONST static inline uint32_t php_pack_reverse_int32(uint32_t arg)
{
uint32_t result;
result = ((arg & 0xFF) << 24) | ((arg & 0xFF00) << 8) | ((arg >> 8) & 0xFF00) | ((arg >> 24) & 0xFF);
return result;
return ZEND_BYTES_SWAP32(arg);
}
/* }}} */
@@ -509,7 +500,7 @@ too_few_args:
case 'c':
case 'C':
while (arg-- > 0) {
php_pack(&argv[currentarg++], 1, byte_map, &ZSTR_VAL(output)[outputpos]);
php_pack(&argv[currentarg++], 1, PHP_MACHINE_ENDIAN, &ZSTR_VAL(output)[outputpos]);
outputpos++;
}
break;
@@ -518,16 +509,16 @@ too_few_args:
case 'S':
case 'n':
case 'v': {
int *map = machine_endian_short_map;
php_pack_endianness endianness = PHP_MACHINE_ENDIAN;
if (code == 'n') {
map = big_endian_short_map;
endianness = PHP_BIG_ENDIAN;
} else if (code == 'v') {
map = little_endian_short_map;
endianness = PHP_LITTLE_ENDIAN;
}
while (arg-- > 0) {
php_pack(&argv[currentarg++], 2, map, &ZSTR_VAL(output)[outputpos]);
php_pack(&argv[currentarg++], 2, endianness, &ZSTR_VAL(output)[outputpos]);
outputpos += 2;
}
break;
@@ -536,7 +527,7 @@ too_few_args:
case 'i':
case 'I':
while (arg-- > 0) {
php_pack(&argv[currentarg++], sizeof(int), int_map, &ZSTR_VAL(output)[outputpos]);
php_pack(&argv[currentarg++], sizeof(int), PHP_MACHINE_ENDIAN, &ZSTR_VAL(output)[outputpos]);
outputpos += sizeof(int);
}
break;
@@ -545,16 +536,16 @@ too_few_args:
case 'L':
case 'N':
case 'V': {
int *map = machine_endian_long_map;
php_pack_endianness endianness = PHP_MACHINE_ENDIAN;
if (code == 'N') {
map = big_endian_long_map;
endianness = PHP_BIG_ENDIAN;
} else if (code == 'V') {
map = little_endian_long_map;
endianness = PHP_LITTLE_ENDIAN;
}
while (arg-- > 0) {
php_pack(&argv[currentarg++], 4, map, &ZSTR_VAL(output)[outputpos]);
php_pack(&argv[currentarg++], 4, endianness, &ZSTR_VAL(output)[outputpos]);
outputpos += 4;
}
break;
@@ -565,16 +556,16 @@ too_few_args:
case 'Q':
case 'J':
case 'P': {
int *map = machine_endian_longlong_map;
php_pack_endianness endianness = PHP_MACHINE_ENDIAN;
if (code == 'J') {
map = big_endian_longlong_map;
endianness = PHP_BIG_ENDIAN;
} else if (code == 'P') {
map = little_endian_longlong_map;
endianness = PHP_LITTLE_ENDIAN;
}
while (arg-- > 0) {
php_pack(&argv[currentarg++], 8, map, &ZSTR_VAL(output)[outputpos]);
php_pack(&argv[currentarg++], 8, endianness, &ZSTR_VAL(output)[outputpos]);
outputpos += 8;
}
break;
@@ -1178,127 +1169,3 @@ no_output:
}
}
/* }}} */
/* {{{ PHP_MINIT_FUNCTION */
PHP_MINIT_FUNCTION(pack)
{
int i;
if (MACHINE_LITTLE_ENDIAN) {
/* Where to get lo to hi bytes from */
byte_map[0] = 0;
for (i = 0; i < (int)sizeof(int); i++) {
int_map[i] = i;
}
machine_endian_short_map[0] = 0;
machine_endian_short_map[1] = 1;
big_endian_short_map[0] = 1;
big_endian_short_map[1] = 0;
little_endian_short_map[0] = 0;
little_endian_short_map[1] = 1;
machine_endian_long_map[0] = 0;
machine_endian_long_map[1] = 1;
machine_endian_long_map[2] = 2;
machine_endian_long_map[3] = 3;
big_endian_long_map[0] = 3;
big_endian_long_map[1] = 2;
big_endian_long_map[2] = 1;
big_endian_long_map[3] = 0;
little_endian_long_map[0] = 0;
little_endian_long_map[1] = 1;
little_endian_long_map[2] = 2;
little_endian_long_map[3] = 3;
#if SIZEOF_ZEND_LONG > 4
machine_endian_longlong_map[0] = 0;
machine_endian_longlong_map[1] = 1;
machine_endian_longlong_map[2] = 2;
machine_endian_longlong_map[3] = 3;
machine_endian_longlong_map[4] = 4;
machine_endian_longlong_map[5] = 5;
machine_endian_longlong_map[6] = 6;
machine_endian_longlong_map[7] = 7;
big_endian_longlong_map[0] = 7;
big_endian_longlong_map[1] = 6;
big_endian_longlong_map[2] = 5;
big_endian_longlong_map[3] = 4;
big_endian_longlong_map[4] = 3;
big_endian_longlong_map[5] = 2;
big_endian_longlong_map[6] = 1;
big_endian_longlong_map[7] = 0;
little_endian_longlong_map[0] = 0;
little_endian_longlong_map[1] = 1;
little_endian_longlong_map[2] = 2;
little_endian_longlong_map[3] = 3;
little_endian_longlong_map[4] = 4;
little_endian_longlong_map[5] = 5;
little_endian_longlong_map[6] = 6;
little_endian_longlong_map[7] = 7;
#endif
}
else {
zval val;
int size = sizeof(Z_LVAL(val));
Z_LVAL(val)=0; /*silence a warning*/
/* Where to get hi to lo bytes from */
byte_map[0] = size - 1;
for (i = 0; i < (int)sizeof(int); i++) {
int_map[i] = size - (sizeof(int) - i);
}
machine_endian_short_map[0] = size - 2;
machine_endian_short_map[1] = size - 1;
big_endian_short_map[0] = size - 2;
big_endian_short_map[1] = size - 1;
little_endian_short_map[0] = size - 1;
little_endian_short_map[1] = size - 2;
machine_endian_long_map[0] = size - 4;
machine_endian_long_map[1] = size - 3;
machine_endian_long_map[2] = size - 2;
machine_endian_long_map[3] = size - 1;
big_endian_long_map[0] = size - 4;
big_endian_long_map[1] = size - 3;
big_endian_long_map[2] = size - 2;
big_endian_long_map[3] = size - 1;
little_endian_long_map[0] = size - 1;
little_endian_long_map[1] = size - 2;
little_endian_long_map[2] = size - 3;
little_endian_long_map[3] = size - 4;
#if SIZEOF_ZEND_LONG > 4
machine_endian_longlong_map[0] = size - 8;
machine_endian_longlong_map[1] = size - 7;
machine_endian_longlong_map[2] = size - 6;
machine_endian_longlong_map[3] = size - 5;
machine_endian_longlong_map[4] = size - 4;
machine_endian_longlong_map[5] = size - 3;
machine_endian_longlong_map[6] = size - 2;
machine_endian_longlong_map[7] = size - 1;
big_endian_longlong_map[0] = size - 8;
big_endian_longlong_map[1] = size - 7;
big_endian_longlong_map[2] = size - 6;
big_endian_longlong_map[3] = size - 5;
big_endian_longlong_map[4] = size - 4;
big_endian_longlong_map[5] = size - 3;
big_endian_longlong_map[6] = size - 2;
big_endian_longlong_map[7] = size - 1;
little_endian_longlong_map[0] = size - 1;
little_endian_longlong_map[1] = size - 2;
little_endian_longlong_map[2] = size - 3;
little_endian_longlong_map[3] = size - 4;
little_endian_longlong_map[4] = size - 5;
little_endian_longlong_map[5] = size - 6;
little_endian_longlong_map[6] = size - 7;
little_endian_longlong_map[7] = size - 8;
#endif
}
return SUCCESS;
}
/* }}} */

View File

@@ -1,22 +0,0 @@
/*
+----------------------------------------------------------------------+
| Copyright (c) The PHP Group |
+----------------------------------------------------------------------+
| This source file is subject to version 3.01 of the PHP license, |
| that is bundled with this package in the file LICENSE, and is |
| available through the world-wide-web at the following url: |
| https://www.php.net/license/3_01.txt |
| If you did not receive a copy of the PHP license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@php.net so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Author: Rasmus Lerdorf <rasmus@lerdorf.on.ca> |
+----------------------------------------------------------------------+
*/
#ifndef PACK_H
#define PACK_H
PHP_MINIT_FUNCTION(pack);
#endif /* PACK_H */

View File

@@ -29,7 +29,6 @@
#include "php_ext_syslog.h"
#include "php_filestat.h"
#include "php_browscap.h"
#include "pack.h"
#include "url.h"
#include "pageinfo.h"
#include "fsock.h"