arch/m68k/lib/muldi3.c

   1 /*
   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
  45 typedef          int SItype     __attribute__ ((mode (SI)));
  46 typedef unsigned int USItype    __attribute__ ((mode (SI)));
  47 typedef          int DItype     __attribute__ ((mode (DI)));
  48 typedef int word_type __attribute__ ((mode (__word__)));
  49
  50 struct DIstruct {SItype high, low;};
  51
  52 typedef union
  53 {
  54         struct DIstruct s;
  55         DItype ll;
  56 } DIunion;
  57
  58 DItype __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 }