linux-IllusionX/arch/m68knommu/lib/muldi3.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

86 lines
2.6 KiB
C

/* muldi3.c extracted from gcc-2.7.2.3/libgcc2.c and
gcc-2.7.2.3/longlong.h which is: */
/* Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
This file is part of GNU CC.
GNU CC 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, or (at your option)
any later version.
GNU CC 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 GNU CC; see the file COPYING. If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#define BITS_PER_UNIT 8
#define SI_TYPE_SIZE 32
#define __BITS4 (SI_TYPE_SIZE / 4)
#define __ll_B (1L << (SI_TYPE_SIZE / 2))
#define __ll_lowpart(t) ((USItype) (t) % __ll_B)
#define __ll_highpart(t) ((USItype) (t) / __ll_B)
#define umul_ppmm(w1, w0, u, v) \
do { \
USItype __x0, __x1, __x2, __x3; \
USItype __ul, __vl, __uh, __vh; \
\
__ul = __ll_lowpart (u); \
__uh = __ll_highpart (u); \
__vl = __ll_lowpart (v); \
__vh = __ll_highpart (v); \
\
__x0 = (USItype) __ul * __vl; \
__x1 = (USItype) __ul * __vh; \
__x2 = (USItype) __uh * __vl; \
__x3 = (USItype) __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)
#define __umulsidi3(u, v) \
({DIunion __w; \
umul_ppmm (__w.s.high, __w.s.low, u, v); \
__w.ll; })
typedef int SItype __attribute__ ((mode (SI)));
typedef unsigned int USItype __attribute__ ((mode (SI)));
typedef int DItype __attribute__ ((mode (DI)));
typedef int word_type __attribute__ ((mode (__word__)));
struct DIstruct {SItype high, low;};
typedef union
{
struct DIstruct s;
DItype ll;
} DIunion;
DItype
__muldi3 (DItype u, DItype v)
{
DIunion w;
DIunion uu, vv;
uu.ll = u,
vv.ll = v;
w.ll = __umulsidi3 (uu.s.low, vv.s.low);
w.s.high += ((USItype) uu.s.low * (USItype) vv.s.high
+ (USItype) uu.s.high * (USItype) vv.s.low);
return w.ll;
}