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#ifndef _LINUX_BYTEORDER_SWABB_H
#define _LINUX_BYTEORDER_SWABB_H
/*
* linux/byteorder/swabb.h
* SWAp Bytes Bizarrely
* swaHHXX[ps]?(foo)
*
* Support for obNUXIous pdp-endian and other bizarre architectures.
* Will Linux ever run on such ancient beasts? if not, this file
* will be but a programming pearl. Still, it's a reminder that we
* shouldn't be making too many assumptions when trying to be portable.
*
*/
/*
* Meaning of the names I chose (vaxlinux people feel free to correct them):
* swahw32 swap 16-bit half-words in a 32-bit word
* swahb32 swap 8-bit halves of each 16-bit half-word in a 32-bit word
*
* No 64-bit support yet. I don't know NUXI conventions for long longs.
* I guarantee it will be a mess when it's there, though :->
* It will be even worse if there are conflicting 64-bit conventions.
* Hopefully, no one ever used 64-bit objects on NUXI machines.
*
*/
#define ___swahw32(x) \
({ \
__u32 __x = (x); \
((__u32)( \
(((__u32)(__x) & (__u32)0x0000ffffUL) << 16) | \
(((__u32)(__x) & (__u32)0xffff0000UL) >> 16) )); \
})
#define ___swahb32(x) \
({ \
__u32 __x = (x); \
((__u32)( \
(((__u32)(__x) & (__u32)0x00ff00ffUL) << 8) | \
(((__u32)(__x) & (__u32)0xff00ff00UL) >> 8) )); \
})
#define ___constant_swahw32(x) \
((__u32)( \
(((__u32)(x) & (__u32)0x0000ffffUL) << 16) | \
(((__u32)(x) & (__u32)0xffff0000UL) >> 16) ))
#define ___constant_swahb32(x) \
((__u32)( \
(((__u32)(x) & (__u32)0x00ff00ffUL) << 8) | \
(((__u32)(x) & (__u32)0xff00ff00UL) >> 8) ))
/*
* provide defaults when no architecture-specific optimization is detected
*/
#ifndef __arch__swahw32
# define __arch__swahw32(x) ___swahw32(x)
#endif
#ifndef __arch__swahb32
# define __arch__swahb32(x) ___swahb32(x)
#endif
#ifndef __arch__swahw32p
# define __arch__swahw32p(x) __swahw32(*(x))
#endif
#ifndef __arch__swahb32p
# define __arch__swahb32p(x) __swahb32(*(x))
#endif
#ifndef __arch__swahw32s
# define __arch__swahw32s(x) do { *(x) = __swahw32p((x)); } while (0)
#endif
#ifndef __arch__swahb32s
# define __arch__swahb32s(x) do { *(x) = __swahb32p((x)); } while (0)
#endif
/*
* Allow constant folding
*/
#if defined(__GNUC__) && (__GNUC__ >= 2) && defined(__OPTIMIZE__)
# define __swahw32(x) \
(__builtin_constant_p((__u32)(x)) ? \
___swahw32((x)) : \
__fswahw32((x)))
# define __swahb32(x) \
(__builtin_constant_p((__u32)(x)) ? \
___swahb32((x)) : \
__fswahb32((x)))
#else
# define __swahw32(x) __fswahw32(x)
# define __swahb32(x) __fswahb32(x)
#endif /* OPTIMIZE */
static inline __u32 __fswahw32(__u32 x)
{
return __arch__swahw32(x);
}
static inline __u32 __swahw32p(__u32 *x)
{
return __arch__swahw32p(x);
}
static inline void __swahw32s(__u32 *addr)
{
__arch__swahw32s(addr);
}
static inline __u32 __fswahb32(__u32 x)
{
return __arch__swahb32(x);
}
static inline __u32 __swahb32p(__u32 *x)
{
return __arch__swahb32p(x);
}
static inline void __swahb32s(__u32 *addr)
{
__arch__swahb32s(addr);
}
#ifdef __BYTEORDER_HAS_U64__
/*
* Not supported yet
*/
#endif /* __BYTEORDER_HAS_U64__ */
#if defined(__KERNEL__)
#define swahw32 __swahw32
#define swahb32 __swahb32
#define swahw32p __swahw32p
#define swahb32p __swahb32p
#define swahw32s __swahw32s
#define swahb32s __swahb32s
#endif
#endif /* _LINUX_BYTEORDER_SWABB_H */
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