mirror of https://gitee.com/openkylin/linux.git
73 lines
2.3 KiB
C
73 lines
2.3 KiB
C
/*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, see the file COPYING, or write
|
|
* to the Free Software Foundation, Inc.
|
|
*/
|
|
|
|
#include <linux/export.h>
|
|
#include <lib/libgcc.h>
|
|
|
|
#define W_TYPE_SIZE 32
|
|
|
|
#define __ll_B ((unsigned long) 1 << (W_TYPE_SIZE / 2))
|
|
#define __ll_lowpart(t) ((unsigned long) (t) & (__ll_B - 1))
|
|
#define __ll_highpart(t) ((unsigned long) (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 { \
|
|
unsigned long __x0, __x1, __x2, __x3; \
|
|
unsigned short __ul, __vl, __uh, __vh; \
|
|
\
|
|
__ul = __ll_lowpart(u); \
|
|
__uh = __ll_highpart(u); \
|
|
__vl = __ll_lowpart(v); \
|
|
__vh = __ll_highpart(v); \
|
|
\
|
|
__x0 = (unsigned long) __ul * __vl; \
|
|
__x1 = (unsigned long) __ul * __vh; \
|
|
__x2 = (unsigned long) __uh * __vl; \
|
|
__x3 = (unsigned long) __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
|
|
|
|
long long notrace __muldi3(long long u, long long v)
|
|
{
|
|
const DWunion uu = {.ll = u};
|
|
const DWunion vv = {.ll = v};
|
|
DWunion w = {.ll = __umulsidi3(uu.s.low, vv.s.low)};
|
|
|
|
w.s.high += ((unsigned long) uu.s.low * (unsigned long) vv.s.high
|
|
+ (unsigned long) uu.s.high * (unsigned long) vv.s.low);
|
|
|
|
return w.ll;
|
|
}
|
|
EXPORT_SYMBOL(__muldi3);
|