arch/blackfin/lib/muldi3.c

   1 /*
   2  * U-boot - muldi3.c contains routines for mult and div
   3  *
   4  * Copyright (c) 2005-2007 Analog Devices Inc.
   5  *
   6  * SPDX-License-Identifier:     GPL-2.0+
   7  */
   8
   9 /* Generic function got from GNU gcc package, libgcc2.c */
  10 #ifndef SI_TYPE_SIZE
  11 #define SI_TYPE_SIZE 32
  12 #endif
  13 #define __ll_B (1L << (SI_TYPE_SIZE / 2))
  14 #define __ll_lowpart(t) ((USItype) (t) % __ll_B)
  15 #define __ll_highpart(t) ((USItype) (t) / __ll_B)
  16 #define BITS_PER_UNIT 8
  17
  18 #if !defined (umul_ppmm)
  19 #define umul_ppmm(w1, w0, u, v)                                         \
  20 do {                                                                    \
  21         USItype __x0, __x1, __x2, __x3;                                 \
  22         USItype __ul, __vl, __uh, __vh;                                 \
  23                                                                         \
  24         __ul = __ll_lowpart (u);                                        \
  25         __uh = __ll_highpart (u);                                       \
  26         __vl = __ll_lowpart (v);                                        \
  27         __vh = __ll_highpart (v);                                       \
  28                                                                         \
  29         __x0 = (USItype) __ul * __vl;                                   \
  30         __x1 = (USItype) __ul * __vh;                                   \
  31         __x2 = (USItype) __uh * __vl;                                   \
  32         __x3 = (USItype) __uh * __vh;                                   \
  33                                                                         \
  34         __x1 += __ll_highpart (__x0);/* this can't give carry */        \
  35         __x1 += __x2;   /* but this indeed can */                       \
  36         if (__x1 < __x2)        /* did we get it? */                    \
  37                 __x3 += __ll_B; /* yes, add it in the proper pos. */    \
  38                                                                         \
  39         (w1) = __x3 + __ll_highpart (__x1);                             \
  40         (w0) = __ll_lowpart (__x1) * __ll_B + __ll_lowpart (__x0);      \
  41 } while (0)
  42 #endif
  43
  44 #if !defined (__umulsidi3)
  45 #define __umulsidi3(u, v)                                               \
  46         ({DIunion __w;                                                  \
  47         umul_ppmm (__w.s.high, __w.s.low, u, v);                        \
  48         __w.ll; })
  49 #endif
  50
  51 typedef unsigned int USItype __attribute__ ((mode(SI)));
  52 typedef int SItype __attribute__ ((mode(SI)));
  53 typedef int DItype __attribute__ ((mode(DI)));
  54 typedef int word_type __attribute__ ((mode(__word__)));
  55
  56 struct DIstruct {
  57         SItype low, high;
  58 };
  59 typedef union {
  60         struct DIstruct s;
  61         DItype ll;
  62 } DIunion;
  63
  64 DItype __muldi3(DItype u, DItype v)
  65 {
  66         DIunion w;
  67         DIunion uu, vv;
  68
  69         uu.ll = u, vv.ll = v;
  70         /*  panic("kernel panic for __muldi3"); */
  71         w.ll = __umulsidi3(uu.s.low, vv.s.low);
  72         w.s.high += ((USItype) uu.s.low * (USItype) vv.s.high
  73                      + (USItype) uu.s.high * (USItype) vv.s.low);
  74
  75         return w.ll;
  76 }