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 }