lunaix-os/arch/i386/includes/sys/muldiv64.h

   1 #ifndef __LUNAIX_MULDIV64_H
   2 #define __LUNAIX_MULDIV64_H
   3
   4 #include <lunaix/spike.h>
   5 #include <lunaix/types.h>
   6
   7 #define do_udiv64(n, base)                                                     \
   8     ({                                                                         \
   9         unsigned long __upper, __low, __high, __mod, __base;                   \
  10         __base = (base);                                                       \
  11         if (__builtin_constant_p(__base) && is_pot(__base)) {                  \
  12             __mod = n & (__base - 1);                                          \
  13             n >>= ILOG2(__base);                                               \
  14         } else {                                                               \
  15             asm("" : "=a"(__low), "=d"(__high) : "A"(n));                      \
  16             __upper = __high;                                                  \
  17             if (__high) {                                                      \
  18                 __upper = __high % (__base);                                   \
  19                 __high = __high / (__base);                                    \
  20             }                                                                  \
  21             asm("divl %2"                                                      \
  22                 : "=a"(__low), "=d"(__mod)                                     \
  23                 : "rm"(__base), "0"(__low), "1"(__upper));                     \
  24             asm("" : "=A"(n) : "a"(__low), "d"(__high));                       \
  25         }                                                                      \
  26         __mod;                                                                 \
  27     })
  28
  29 static inline u64_t
  30 udiv64(u64_t n, unsigned int base)
  31 {
  32     do_udiv64(n, base);
  33
  34     return n;
  35 }
  36
  37 static inline unsigned int
  38 umod64(u64_t n, unsigned int base)
  39 {
  40     return do_udiv64(n, base);
  41 }
  42
  43 #endif /* __LUNAIX_MULDIV64_H */