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#include <linux/module.h>
#include "libgcc.h"
#define DWtype long long
#define UWtype unsigned long
#define UHWtype unsigned short
#define W_TYPE_SIZE 32
#define __ll_B ((UWtype) 1 << (W_TYPE_SIZE / 2))
#define __ll_lowpart(t) ((UWtype) (t) & (__ll_B - 1))
#define __ll_highpart(t) ((UWtype) (t) >> (W_TYPE_SIZE / 2))
/* If we still don't have umul_ppmm, define it using plain C. */
#if !defined(umul_ppmm)
#define umul_ppmm(w1, w0, u, v) \
do { \
UWtype __x0, __x1, __x2, __x3; \
UHWtype __ul, __vl, __uh, __vh; \
\
__ul = __ll_lowpart(u); \
__uh = __ll_highpart(u); \
__vl = __ll_lowpart(v); \
__vh = __ll_highpart(v); \
\
__x0 = (UWtype) __ul * __vl; \
__x1 = (UWtype) __ul * __vh; \
__x2 = (UWtype) __uh * __vl; \
__x3 = (UWtype) __uh * __vh; \
\
__x1 += __ll_highpart(__x0); /* this can't give carry */\
__x1 += __x2; /* but this indeed can */ \
if (__x1 < __x2) /* did we get it? */ \
__x3 += __ll_B; /* yes, add it in the proper pos */ \
\
(w1) = __x3 + __ll_highpart(__x1); \
(w0) = __ll_lowpart(__x1) * __ll_B + __ll_lowpart(__x0);\
} while (0)
#endif
#if !defined(__umulsidi3)
#define __umulsidi3(u, v) ({ \
DWunion __w; \
umul_ppmm(__w.s.high, __w.s.low, u, v); \
__w.ll; \
})
#endif
DWtype __muldi3(DWtype u, DWtype v)
{
const DWunion uu = {.ll = u};
const DWunion vv = {.ll = v};
DWunion w = {.ll = __umulsidi3(uu.s.low, vv.s.low)};
w.s.high += ((UWtype) uu.s.low * (UWtype) vv.s.high
+ (UWtype) uu.s.high * (UWtype) vv.s.low);
return w.ll;
}
EXPORT_SYMBOL(__muldi3);
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