| Current Path : /usr/include/bits/ |
Linux gator3171.hostgator.com 4.19.286-203.ELK.el7.x86_64 #1 SMP Wed Jun 14 04:33:55 CDT 2023 x86_64 |
| Current File : //usr/include/bits/byteswap.h |
/* Macros to swap the order of bytes in integer values.
Copyright (C) 1997-2012 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#if !defined _BYTESWAP_H && !defined _NETINET_IN_H && !defined _ENDIAN_H
# error "Never use <bits/byteswap.h> directly; include <byteswap.h> instead."
#endif
#ifndef _BITS_BYTESWAP_H
#define _BITS_BYTESWAP_H 1
#include <features.h>
#include <bits/types.h>
#include <bits/wordsize.h>
/* Swap bytes in 16 bit value. */
#define __bswap_constant_16(x) \
((unsigned short int) ((((x) >> 8) & 0xff) | (((x) & 0xff) << 8)))
/* Get __bswap_16. */
#include <bits/byteswap-16.h>
/* Swap bytes in 32 bit value. */
#define __bswap_constant_32(x) \
((((x) & 0xff000000) >> 24) | (((x) & 0x00ff0000) >> 8) | \
(((x) & 0x0000ff00) << 8) | (((x) & 0x000000ff) << 24))
#ifdef __GNUC__
# if __GNUC_PREREQ (4, 3)
static __inline unsigned int
__bswap_32 (unsigned int __bsx)
{
return __builtin_bswap32 (__bsx);
}
# elif __GNUC__ >= 2
# if __WORDSIZE == 64 || (defined __i486__ || defined __pentium__ \
|| defined __pentiumpro__ || defined __pentium4__ \
|| defined __k8__ || defined __athlon__ \
|| defined __k6__ || defined __nocona__ \
|| defined __core2__ || defined __geode__ \
|| defined __amdfam10__)
/* To swap the bytes in a word the i486 processors and up provide the
`bswap' opcode. On i386 we have to use three instructions. */
# define __bswap_32(x) \
(__extension__ \
({ unsigned int __v, __x = (x); \
if (__builtin_constant_p (__x)) \
__v = __bswap_constant_32 (__x); \
else \
__asm__ ("bswap %0" : "=r" (__v) : "0" (__x)); \
__v; }))
# else
# define __bswap_32(x) \
(__extension__ \
({ unsigned int __v, __x = (x); \
if (__builtin_constant_p (__x)) \
__v = __bswap_constant_32 (__x); \
else \
__asm__ ("rorw $8, %w0;" \
"rorl $16, %0;" \
"rorw $8, %w0" \
: "=r" (__v) \
: "0" (__x) \
: "cc"); \
__v; }))
# endif
# else
# define __bswap_32(x) \
(__extension__ \
({ unsigned int __x = (x); __bswap_constant_32 (__x); }))
# endif
#else
static __inline unsigned int
__bswap_32 (unsigned int __bsx)
{
return __bswap_constant_32 (__bsx);
}
#endif
#if __GNUC_PREREQ (2, 0)
/* Swap bytes in 64 bit value. */
# define __bswap_constant_64(x) \
(__extension__ ((((x) & 0xff00000000000000ull) >> 56) \
| (((x) & 0x00ff000000000000ull) >> 40) \
| (((x) & 0x0000ff0000000000ull) >> 24) \
| (((x) & 0x000000ff00000000ull) >> 8) \
| (((x) & 0x00000000ff000000ull) << 8) \
| (((x) & 0x0000000000ff0000ull) << 24) \
| (((x) & 0x000000000000ff00ull) << 40) \
| (((x) & 0x00000000000000ffull) << 56)))
# if __GNUC_PREREQ (4, 3)
static __inline __uint64_t
__bswap_64 (__uint64_t __bsx)
{
return __builtin_bswap64 (__bsx);
}
# elif __WORDSIZE == 64
# define __bswap_64(x) \
(__extension__ \
({ __uint64_t __v, __x = (x); \
if (__builtin_constant_p (__x)) \
__v = __bswap_constant_64 (__x); \
else \
__asm__ ("bswap %q0" : "=r" (__v) : "0" (__x)); \
__v; }))
# else
# define __bswap_64(x) \
(__extension__ \
({ union { __extension__ __uint64_t __ll; \
unsigned int __l[2]; } __w, __r; \
if (__builtin_constant_p (x)) \
__r.__ll = __bswap_constant_64 (x); \
else \
{ \
__w.__ll = (x); \
__r.__l[0] = __bswap_32 (__w.__l[1]); \
__r.__l[1] = __bswap_32 (__w.__l[0]); \
} \
__r.__ll; }))
# endif
#elif __GLIBC_HAVE_LONG_LONG
# define __bswap_constant_64(x) \
((((x) & 0xff00000000000000ull) >> 56) \
| (((x) & 0x00ff000000000000ull) >> 40) \
| (((x) & 0x0000ff0000000000ull) >> 24) \
| (((x) & 0x000000ff00000000ull) >> 8) \
| (((x) & 0x00000000ff000000ull) << 8) \
| (((x) & 0x0000000000ff0000ull) << 24) \
| (((x) & 0x000000000000ff00ull) << 40) \
| (((x) & 0x00000000000000ffull) << 56))
static __inline __uint64_t
__bswap_64 (__uint64_t __bsx)
{
return __bswap_constant_64 (__bsx);
}
#endif
#endif /* _BITS_BYTESWAP_H */