linux/arch/microblaze/lib/muldi3.c
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   1#include <linux/export.h>
   2
   3#include "libgcc.h"
   4
   5#define W_TYPE_SIZE 32
   6
   7#define __ll_B ((unsigned long) 1 << (W_TYPE_SIZE / 2))
   8#define __ll_lowpart(t) ((unsigned long) (t) & (__ll_B - 1))
   9#define __ll_highpart(t) ((unsigned long) (t) >> (W_TYPE_SIZE / 2))
  10
  11/* If we still don't have umul_ppmm, define it using plain C.  */
  12#if !defined(umul_ppmm)
  13#define umul_ppmm(w1, w0, u, v)                                         \
  14        do {                                                            \
  15                unsigned long __x0, __x1, __x2, __x3;                   \
  16                unsigned short __ul, __vl, __uh, __vh;                  \
  17                                                                        \
  18                __ul = __ll_lowpart(u);                                 \
  19                __uh = __ll_highpart(u);                                \
  20                __vl = __ll_lowpart(v);                                 \
  21                __vh = __ll_highpart(v);                                \
  22                                                                        \
  23                __x0 = (unsigned long) __ul * __vl;                     \
  24                __x1 = (unsigned long) __ul * __vh;                     \
  25                __x2 = (unsigned long) __uh * __vl;                     \
  26                __x3 = (unsigned long) __uh * __vh;                     \
  27                                                                        \
  28                __x1 += __ll_highpart(__x0); /* this can't give carry */\
  29                __x1 += __x2; /* but this indeed can */                 \
  30                if (__x1 < __x2) /* did we get it? */                   \
  31                __x3 += __ll_B; /* yes, add it in the proper pos */     \
  32                                                                        \
  33                (w1) = __x3 + __ll_highpart(__x1);                      \
  34                (w0) = __ll_lowpart(__x1) * __ll_B + __ll_lowpart(__x0);\
  35        } while (0)
  36#endif
  37
  38#if !defined(__umulsidi3)
  39#define __umulsidi3(u, v) ({                            \
  40        DWunion __w;                                    \
  41        umul_ppmm(__w.s.high, __w.s.low, u, v);         \
  42        __w.ll;                                         \
  43        })
  44#endif
  45
  46long long __muldi3(long long u, long long v)
  47{
  48        const DWunion uu = {.ll = u};
  49        const DWunion vv = {.ll = v};
  50        DWunion w = {.ll = __umulsidi3(uu.s.low, vv.s.low)};
  51
  52        w.s.high += ((unsigned long) uu.s.low * (unsigned long) vv.s.high
  53                + (unsigned long) uu.s.high * (unsigned long) vv.s.low);
  54
  55        return w.ll;
  56}
  57EXPORT_SYMBOL(__muldi3);
  58