diff options
Diffstat (limited to 'sysdeps/i386')
| -rw-r--r-- | sysdeps/i386/bits/byteswap.h | 41 |
1 files changed, 28 insertions, 13 deletions
diff --git a/sysdeps/i386/bits/byteswap.h b/sysdeps/i386/bits/byteswap.h index db8b15d4d3..0d7d75cb42 100644 --- a/sysdeps/i386/bits/byteswap.h +++ b/sysdeps/i386/bits/byteswap.h @@ -28,8 +28,9 @@ #define __bswap_constant_16(x) \ ((((x) >> 8) & 0xff) | (((x) & 0xff) << 8)) -#if defined __GNUC__ && __GNUC__ >= 2 -# define __bswap_16(x) \ +#ifdef __GNUC__ +# if __GNUC__ >= 2 +# define __bswap_16(x) \ (__extension__ \ ({ register unsigned short int __v, __x = (x); \ if (__builtin_constant_p (__x)) \ @@ -40,24 +41,31 @@ : "0" (__x) \ : "cc"); \ __v; })) -#else +# else /* This is better than nothing. */ -# define __bswap_16(x) \ +# define __bswap_16(x) \ (__extension__ \ ({ register unsigned short int __x = (x); __bswap_constant_16 (__x); })) +# endif +#else +static __inline unsigned short int +__bswap_16 (unsigned short int __bsx) +{ + return __bswap_constant_16 (__bsx); +} #endif - /* Swap bytes in 32 bit value. */ #define __bswap_constant_32(x) \ ((((x) & 0xff000000) >> 24) | (((x) & 0x00ff0000) >> 8) | \ (((x) & 0x0000ff00) << 8) | (((x) & 0x000000ff) << 24)) -#if defined __GNUC__ && __GNUC__ >= 2 +#ifdef __GNUC__ +# if __GNUC__ >= 2 /* To swap the bytes in a word the i486 processors and up provide the `bswap' opcode. On i386 we have to use three instructions. */ -# if !defined __i486__ && !defined __pentium__ && !defined __pentiumpro__ -# define __bswap_32(x) \ +# if !defined __i486__ && !defined __pentium__ && !defined __pentiumpro__ +# define __bswap_32(x) \ (__extension__ \ ({ register unsigned int __v, __x = (x); \ if (__builtin_constant_p (__x)) \ @@ -70,8 +78,8 @@ : "0" (__x) \ : "cc"); \ __v; })) -# else -# define __bswap_32(x) \ +# else +# define __bswap_32(x) \ (__extension__ \ ({ register unsigned int __v, __x = (x); \ if (__builtin_constant_p (__x)) \ @@ -79,11 +87,18 @@ else \ __asm__ ("bswap %0" : "=r" (__v) : "0" (__x)); \ __v; })) -# endif -#else -# define __bswap_32(x) \ +# endif +# else +# define __bswap_32(x) \ (__extension__ \ ({ register 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 |