mirror of
https://github.com/torvalds/linux.git
synced 2024-12-26 21:02:19 +00:00
3370d82f3b
__muldi3 was written for big endian platforms. Code contained half word read/write instructions which are not compatible with little endian cpu. Asm __muldi3 implementation is replaced by C version. Signed-off-by: Michal Simek <monstr@monstr.eu>
61 lines
1.6 KiB
C
61 lines
1.6 KiB
C
#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;
|
|
}
|