swab.h 1.2 KB

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  1. #ifndef _ASM_X86_SWAB_H
  2. #define _ASM_X86_SWAB_H
  3. #include <linux/types.h>
  4. static __inline__ __u32 __arch_swab32(__u32 val)
  5. {
  6. #ifdef __i386__
  7. # ifdef CONFIG_X86_BSWAP
  8. __asm__("bswap %0" : "=r" (val) : "0" (val));
  9. # else
  10. __asm__("xchgb %b0,%h0\n\t" /* swap lower bytes */
  11. "rorl $16,%0\n\t" /* swap words */
  12. "xchgb %b0,%h0" /* swap higher bytes */
  13. : "=q" (val)
  14. : "0" (val));
  15. # endif
  16. #else /* __i386__ */
  17. __asm__("bswapl %0"
  18. : "=r" (val)
  19. : "0" (val));
  20. #endif
  21. return val;
  22. }
  23. #define __arch_swab32 __arch_swab32
  24. static __inline__ __u64 __arch_swab64(__u64 val)
  25. {
  26. #ifdef __i386__
  27. union {
  28. struct {
  29. __u32 a;
  30. __u32 b;
  31. } s;
  32. __u64 u;
  33. } v;
  34. v.u = val;
  35. # ifdef CONFIG_X86_BSWAP
  36. __asm__("bswapl %0 ; bswapl %1 ; xchgl %0,%1"
  37. : "=r" (v.s.a), "=r" (v.s.b)
  38. : "0" (v.s.a), "1" (v.s.b));
  39. # else
  40. v.s.a = __arch_swab32(v.s.a);
  41. v.s.b = __arch_swab32(v.s.b);
  42. __asm__("xchgl %0,%1"
  43. : "=r" (v.s.a), "=r" (v.s.b)
  44. : "0" (v.s.a), "1" (v.s.b));
  45. # endif
  46. return v.u;
  47. #else /* __i386__ */
  48. __asm__("bswapq %0"
  49. : "=r" (val)
  50. : "0" (val));
  51. return val;
  52. #endif
  53. }
  54. #define __arch_swab64 __arch_swab64
  55. #endif /* _ASM_X86_SWAB_H */