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      1 #ifndef _ASM_X86_SWAB_H
      2 #define _ASM_X86_SWAB_H
      3 
      4 #include <linux/types.h>
      5 
      6 
      7 static __inline__ __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__ __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 */
     62