blob: d709c32145361d17cb0ce6e5e244589b3b921601 [file] [log] [blame]
angelo@sysam.it5e798172015-12-06 17:47:59 +01001/*
2 * muldi3.c extracted from gcc-2.7.2.3/libgcc2.c and
3 * gcc-2.7.2.3/longlong.h
4 *
5 * Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
6 *
7 * SPDX-License-Identifier: GPL-2.0+
8 */
9
10#define SI_TYPE_SIZE 32
11#define __BITS4 (SI_TYPE_SIZE / 4)
12#define __ll_B (1L << (SI_TYPE_SIZE / 2))
13#define __ll_lowpart(t) ((USItype) (t) % __ll_B)
14#define __ll_highpart(t) ((USItype) (t) / __ll_B)
15
16#define umul_ppmm(w1, w0, u, v) \
17 do { \
18 USItype __x0, __x1, __x2, __x3; \
19 USItype __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 = (USItype) __ul * __vl; \
27 __x1 = (USItype) __ul * __vh; \
28 __x2 = (USItype) __uh * __vl; \
29 __x3 = (USItype) __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
40#define __umulsidi3(u, v) \
41 ({DIunion __w; \
42 umul_ppmm (__w.s.high, __w.s.low, u, v); \
43 __w.ll; })
44
45typedef int SItype __attribute__ ((mode (SI)));
46typedef unsigned int USItype __attribute__ ((mode (SI)));
47typedef int DItype __attribute__ ((mode (DI)));
48typedef int word_type __attribute__ ((mode (__word__)));
49
50struct DIstruct {SItype high, low;};
51
52typedef union
53{
54 struct DIstruct s;
55 DItype ll;
56} DIunion;
57
58DItype __muldi3 (DItype u, DItype v)
59{
60 DIunion w;
61 DIunion uu, vv;
62
63 uu.ll = u,
64 vv.ll = v;
65
66 w.ll = __umulsidi3 (uu.s.low, vv.s.low);
67 w.s.high += ((USItype) uu.s.low * (USItype) vv.s.high
68 + (USItype) uu.s.high * (USItype) vv.s.low);
69
70 return w.ll;
71}