1 #ifndef _ASM_X86_SWAB_H

     2 #define _ASM_X86_SWAB_H

     3 

     4 #include <linux/types.h>

     5 #include <linux/compiler.h>

     6 

     7 static inline __attribute_const__ __u32 __arch_swab32(__u32 val)

     8 {

     9 #ifdef __i386__

    10 # ifdef CONFIG_X86_BSWAP

    11 	asm("bswap %0" : "=r" (val) : "0" (val));

    12 # else

    13 	asm("xchgb %b0,%h0\n\t"	/* swap lower bytes	*/

    14 	    "rorl $16,%0\n\t"	/* swap words		*/

    15 	    "xchgb %b0,%h0"	/* swap higher bytes	*/

    16 	    : "=q" (val)

    17 	    : "0" (val));

    18 # endif

    19 

    20 #else /* __i386__ */

    21 	asm("bswapl %0"

    22 	    : "=r" (val)

    23 	    : "0" (val));

    24 #endif

    25 	return val;

    26 }

    27 #define __arch_swab32 __arch_swab32

    28 

    29 static inline __attribute_const__ __u64 __arch_swab64(__u64 val)

    30 {

    31 #ifdef __i386__

    32 	union {

    33 		struct {

    34 			__u32 a;

    35 			__u32 b;

    36 		} s;

    37 		__u64 u;

    38 	} v;

    39 	v.u = val;

    40 # ifdef CONFIG_X86_BSWAP

    41 	asm("bswapl %0 ; bswapl %1 ; xchgl %0,%1"

    42 	    : "=r" (v.s.a), "=r" (v.s.b)

    43 	    : "0" (v.s.a), "1" (v.s.b));

    44 # else

    45 	v.s.a = __arch_swab32(v.s.a);

    46 	v.s.b = __arch_swab32(v.s.b);

    47 	asm("xchgl %0,%1"

    48 	    : "=r" (v.s.a), "=r" (v.s.b)

    49 	    : "0" (v.s.a), "1" (v.s.b));

    50 # endif

    51 	return v.u;

    52 #else /* __i386__ */

    53 	asm("bswapq %0"

    54 	    : "=r" (val)

    55 	    : "0" (val));

    56 	return val;

    57 #endif

    58 }

    59 #define __arch_swab64 __arch_swab64

    60 

    61 #endif /* _ASM_X86_SWAB_H */