Merge git://git.infradead.org/mtd-2.6
[linux-2.6.git] / arch / m68knommu / lib / muldi3.c
1 /* muldi3.c extracted from gcc-2.7.2.3/libgcc2.c and 
2                            gcc-2.7.2.3/longlong.h which is: */
3 /* Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
4
5 This file is part of GNU CC.
6
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
11
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING.  If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA.  */
21
22 #define BITS_PER_UNIT 8
23 #define SI_TYPE_SIZE 32
24
25 #define __BITS4 (SI_TYPE_SIZE / 4)
26 #define __ll_B (1L << (SI_TYPE_SIZE / 2))
27 #define __ll_lowpart(t) ((USItype) (t) % __ll_B)
28 #define __ll_highpart(t) ((USItype) (t) / __ll_B)
29
30 #define umul_ppmm(w1, w0, u, v)                                         \
31   do {                                                                  \
32     USItype __x0, __x1, __x2, __x3;                                     \
33     USItype __ul, __vl, __uh, __vh;                                     \
34                                                                         \
35     __ul = __ll_lowpart (u);                                            \
36     __uh = __ll_highpart (u);                                           \
37     __vl = __ll_lowpart (v);                                            \
38     __vh = __ll_highpart (v);                                           \
39                                                                         \
40     __x0 = (USItype) __ul * __vl;                                       \
41     __x1 = (USItype) __ul * __vh;                                       \
42     __x2 = (USItype) __uh * __vl;                                       \
43     __x3 = (USItype) __uh * __vh;                                       \
44                                                                         \
45     __x1 += __ll_highpart (__x0);/* this can't give carry */            \
46     __x1 += __x2;               /* but this indeed can */               \
47     if (__x1 < __x2)            /* did we get it? */                    \
48       __x3 += __ll_B;           /* yes, add it in the proper pos. */    \
49                                                                         \
50     (w1) = __x3 + __ll_highpart (__x1);                                 \
51     (w0) = __ll_lowpart (__x1) * __ll_B + __ll_lowpart (__x0);          \
52   } while (0)
53
54 #define __umulsidi3(u, v) \
55   ({DIunion __w;                                                        \
56     umul_ppmm (__w.s.high, __w.s.low, u, v);                            \
57     __w.ll; })
58
59 typedef          int SItype     __attribute__ ((mode (SI)));
60 typedef unsigned int USItype    __attribute__ ((mode (SI)));
61 typedef          int DItype     __attribute__ ((mode (DI)));
62 typedef int word_type __attribute__ ((mode (__word__)));
63
64 struct DIstruct {SItype high, low;};
65
66 typedef union
67 {
68   struct DIstruct s;
69   DItype ll;
70 } DIunion;
71
72 DItype
73 __muldi3 (DItype u, DItype v)
74 {
75   DIunion w;
76   DIunion uu, vv;
77
78   uu.ll = u,
79   vv.ll = v;
80
81   w.ll = __umulsidi3 (uu.s.low, vv.s.low);
82   w.s.high += ((USItype) uu.s.low * (USItype) vv.s.high
83                + (USItype) uu.s.high * (USItype) vv.s.low);
84
85   return w.ll;
86 }