arch/microblaze/lib/muldi3.c

   1 /*
   2  * U-boot - muldi3.c contains routines for mult and div
   3  *
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  21  * MA 02110-1301 USA
  22  */
  23
  24 /* Generic function got from GNU gcc package, libgcc2.c */
  25 #ifndef SI_TYPE_SIZE
  26 #define SI_TYPE_SIZE 32
  27 #endif
  28 #define __ll_B (1L << (SI_TYPE_SIZE / 2))
  29 #define __ll_lowpart(t) ((USItype) (t) % __ll_B)
  30 #define __ll_highpart(t) ((USItype) (t) / __ll_B)
  31 #define BITS_PER_UNIT 8
  32
  33 #if !defined(umul_ppmm)
  34 #define umul_ppmm(w1, w0, u, v)                                         \
  35         do {                                                            \
  36         USItype __x0, __x1, __x2, __x3;                                 \
  37         USItype __ul, __vl, __uh, __vh;                                 \
  38                                                                         \
  39                 __ul = __ll_lowpart(u);                                 \
  40                 __uh = __ll_highpart(u);                                \
  41                 __vl = __ll_lowpart(v);                                 \
  42                 __vh = __ll_highpart(v);                                \
  43                                                                         \
  44         __x0 = (USItype) __ul * __vl;                                   \
  45         __x1 = (USItype) __ul * __vh;                                   \
  46         __x2 = (USItype) __uh * __vl;                                   \
  47         __x3 = (USItype) __uh * __vh;                                   \
  48                                                                         \
  49                 __x1 += __ll_highpart(__x0); /* this can't give carry */\
  50                 __x1 += __x2; /* but this indeed can */                 \
  51                 if (__x1 < __x2) /* did we get it? */                   \
  52                 __x3 += __ll_B; /* yes, add it in the proper pos. */    \
  53                                                                         \
  54                 (w1) = __x3 + __ll_highpart(__x1);                      \
  55                 (w0) = __ll_lowpart(__x1) * __ll_B + __ll_lowpart(__x0);\
  56         } while (0)
  57 #endif
  58
  59 #if !defined(__umulsidi3)
  60 #define __umulsidi3(u, v)                                               \
  61         ({DIunion __w;                                                  \
  62         umul_ppmm(__w.s.high, __w.s.low, u, v);         \
  63         __w.ll; })
  64 #endif
  65
  66 typedef unsigned int USItype __attribute__ ((mode(SI)));
  67 typedef int SItype __attribute__ ((mode(SI)));
  68 typedef int DItype __attribute__ ((mode(DI)));
  69 typedef int word_type __attribute__ ((mode(__word__)));
  70
  71 struct DIstruct {
  72         SItype low, high;
  73 };
  74 typedef union {
  75         struct DIstruct s;
  76         DItype ll;
  77 } DIunion;
  78
  79 DItype __muldi3(DItype u, DItype v)
  80 {
  81         DIunion w;
  82         DIunion uu, vv;
  83
  84         uu.ll = u, vv.ll = v;
  85         /*  panic("kernel panic for __muldi3"); */
  86         w.ll = __umulsidi3(uu.s.low, vv.s.low);
  87         w.s.high += ((USItype) uu.s.low * (USItype) vv.s.high
  88                      + (USItype) uu.s.high * (USItype) vv.s.low);
  89
  90         return w.ll;
  91 }