1// SPDX-License-Identifier: GPL-2.0-or-later
 2/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 3 */
 4
 5#include <linux/export.h>
 6#include <linux/libgcc.h>
 7
 8#define W_TYPE_SIZE 32
 9
10#define __ll_B ((unsigned long) 1 << (W_TYPE_SIZE / 2))
11#define __ll_lowpart(t) ((unsigned long) (t) & (__ll_B - 1))
12#define __ll_highpart(t) ((unsigned long) (t) >> (W_TYPE_SIZE / 2))
13
14/* If we still don't have umul_ppmm, define it using plain C.  */
15#if !defined(umul_ppmm)
16#define umul_ppmm(w1, w0, u, v)						\
17	do {								\
18		unsigned long __x0, __x1, __x2, __x3;			\
19		unsigned short __ul, __vl, __uh, __vh;			\
20									\
21		__ul = __ll_lowpart(u);					\
22		__uh = __ll_highpart(u);				\
23		__vl = __ll_lowpart(v);					\
24		__vh = __ll_highpart(v);				\
25									\
26		__x0 = (unsigned long) __ul * __vl;			\
27		__x1 = (unsigned long) __ul * __vh;			\
28		__x2 = (unsigned long) __uh * __vl;			\
29		__x3 = (unsigned long) __uh * __vh;			\
30									\
31		__x1 += __ll_highpart(__x0); /* this can't give carry */\
32		__x1 += __x2; /* but this indeed can */			\
33		if (__x1 < __x2) /* did we get it? */			\
34		__x3 += __ll_B; /* yes, add it in the proper pos */	\
35									\
36		(w1) = __x3 + __ll_highpart(__x1);			\
37		(w0) = __ll_lowpart(__x1) * __ll_B + __ll_lowpart(__x0);\
38	} while (0)
39#endif
40
41#if !defined(__umulsidi3)
42#define __umulsidi3(u, v) ({				\
43	DWunion __w;					\
44	umul_ppmm(__w.s.high, __w.s.low, u, v);		\
45	__w.ll;						\
46	})
47#endif
48
49long long notrace __muldi3(long long u, long long v)
50{
51	const DWunion uu = {.ll = u};
52	const DWunion vv = {.ll = v};
53	DWunion w = {.ll = __umulsidi3(uu.s.low, vv.s.low)};
54
55	w.s.high += ((unsigned long) uu.s.low * (unsigned long) vv.s.high
56		+ (unsigned long) uu.s.high * (unsigned long) vv.s.low);
57
58	return w.ll;
59}
60EXPORT_SYMBOL(__muldi3);

 
 1/*
 2 * This program is free software; you can redistribute it and/or modify
 3 * it under the terms of the GNU General Public License as published by
 4 * the Free Software Foundation; either version 2 of the License, or
 5 * (at your option) any later version.
 6 *
 7 * This program is distributed in the hope that it will be useful,
 8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, see the file COPYING, or write
14 * to the Free Software Foundation, Inc.
15 */
16
17#include <linux/export.h>
18#include <linux/libgcc.h>
19
20#define W_TYPE_SIZE 32
21
22#define __ll_B ((unsigned long) 1 << (W_TYPE_SIZE / 2))
23#define __ll_lowpart(t) ((unsigned long) (t) & (__ll_B - 1))
24#define __ll_highpart(t) ((unsigned long) (t) >> (W_TYPE_SIZE / 2))
25
26/* If we still don't have umul_ppmm, define it using plain C.  */
27#if !defined(umul_ppmm)
28#define umul_ppmm(w1, w0, u, v)						\
29	do {								\
30		unsigned long __x0, __x1, __x2, __x3;			\
31		unsigned short __ul, __vl, __uh, __vh;			\
32									\
33		__ul = __ll_lowpart(u);					\
34		__uh = __ll_highpart(u);				\
35		__vl = __ll_lowpart(v);					\
36		__vh = __ll_highpart(v);				\
37									\
38		__x0 = (unsigned long) __ul * __vl;			\
39		__x1 = (unsigned long) __ul * __vh;			\
40		__x2 = (unsigned long) __uh * __vl;			\
41		__x3 = (unsigned long) __uh * __vh;			\
42									\
43		__x1 += __ll_highpart(__x0); /* this can't give carry */\
44		__x1 += __x2; /* but this indeed can */			\
45		if (__x1 < __x2) /* did we get it? */			\
46		__x3 += __ll_B; /* yes, add it in the proper pos */	\
47									\
48		(w1) = __x3 + __ll_highpart(__x1);			\
49		(w0) = __ll_lowpart(__x1) * __ll_B + __ll_lowpart(__x0);\
50	} while (0)
51#endif
52
53#if !defined(__umulsidi3)
54#define __umulsidi3(u, v) ({				\
55	DWunion __w;					\
56	umul_ppmm(__w.s.high, __w.s.low, u, v);		\
57	__w.ll;						\
58	})
59#endif
60
61long long notrace __muldi3(long long u, long long v)
62{
63	const DWunion uu = {.ll = u};
64	const DWunion vv = {.ll = v};
65	DWunion w = {.ll = __umulsidi3(uu.s.low, vv.s.low)};
66
67	w.s.high += ((unsigned long) uu.s.low * (unsigned long) vv.s.high
68		+ (unsigned long) uu.s.high * (unsigned long) vv.s.low);
69
70	return w.ll;
71}
72EXPORT_SYMBOL(__muldi3);