libgfortran/generated/eoshift1_8.c

   1 /* Implementation of the EOSHIFT intrinsic
   2    Copyright 2002, 2005 Free Software Foundation, Inc.
   3    Contributed by Paul Brook <paul@nowt.org>
   4
   5 This file is part of the GNU Fortran 95 runtime library (libgfortran).
   6
   7 Libgfortran is free software; you can redistribute it and/or
   8 modify it under the terms of the GNU General Public
   9 License as published by the Free Software Foundation; either
  10 version 2 of the License, or (at your option) any later version.
  11
  12 In addition to the permissions in the GNU General Public License, the
  13 Free Software Foundation gives you unlimited permission to link the
  14 compiled version of this file into combinations with other programs,
  15 and to distribute those combinations without any restriction coming
  16 from the use of this file.  (The General Public License restrictions
  17 do apply in other respects; for example, they cover modification of
  18 the file, and distribution when not linked into a combine
  19 executable.)
  20
  21 Libgfortran is distributed in the hope that it will be useful,
  22 but WITHOUT ANY WARRANTY; without even the implied warranty of
  23 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24 GNU General Public License for more details.
  25
  26 You should have received a copy of the GNU General Public
  27 License along with libgfortran; see the file COPYING.  If not,
  28 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  29 Boston, MA 02111-1307, USA.  */
  30
  31 #include "config.h"
  32 #include <stdlib.h>
  33 #include <assert.h>
  34 #include <string.h>
  35 #include "libgfortran.h"
  36
  37 static const char zeros[16] =
  38   {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
  39
  40 extern void eoshift1_8 (const gfc_array_char *,
  41                                      const gfc_array_char *,
  42                                      const gfc_array_i8 *, const char *,
  43                                      const GFC_INTEGER_8 *);
  44 export_proto(eoshift1_8);
  45
  46 void
  47 eoshift1_8 (const gfc_array_char *ret,
  48                        const gfc_array_char *array,
  49                        const gfc_array_i8 *h, const char *pbound,
  50                        const GFC_INTEGER_8 *pwhich)
  51 {
  52   /* r.* indicates the return array.  */
  53   index_type rstride[GFC_MAX_DIMENSIONS];
  54   index_type rstride0;
  55   index_type roffset;
  56   char *rptr;
  57   char *dest;
  58   /* s.* indicates the source array.  */
  59   index_type sstride[GFC_MAX_DIMENSIONS];
  60   index_type sstride0;
  61   index_type soffset;
  62   const char *sptr;
  63   const char *src;
  64   /* h.* indicates the shift array.  */
  65   index_type hstride[GFC_MAX_DIMENSIONS];
  66   index_type hstride0;
  67   const GFC_INTEGER_8 *hptr;
  68
  69   index_type count[GFC_MAX_DIMENSIONS];
  70   index_type extent[GFC_MAX_DIMENSIONS];
  71   index_type dim;
  72   index_type size;
  73   index_type len;
  74   index_type n;
  75   int which;
  76   GFC_INTEGER_8 sh;
  77   GFC_INTEGER_8 delta;
  78
  79   /* The compiler cannot figure out that these are set, initialize
  80      them to avoid warnings.  */
  81   len = 0;
  82   soffset = 0;
  83   roffset = 0;
  84
  85   if (pwhich)
  86     which = *pwhich - 1;
  87   else
  88     which = 0;
  89
  90   if (!pbound)
  91     pbound = zeros;
  92
  93   size = GFC_DESCRIPTOR_SIZE (ret);
  94
  95   extent[0] = 1;
  96   count[0] = 0;
  97   size = GFC_DESCRIPTOR_SIZE (array);
  98   n = 0;
  99   for (dim = 0; dim < GFC_DESCRIPTOR_RANK (array); dim++)
 100     {
 101       if (dim == which)
 102         {
 103           roffset = ret->dim[dim].stride * size;
 104           if (roffset == 0)
 105             roffset = size;
 106           soffset = array->dim[dim].stride * size;
 107           if (soffset == 0)
 108             soffset = size;
 109           len = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
 110         }
 111       else
 112         {
 113           count[n] = 0;
 114           extent[n] = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
 115           rstride[n] = ret->dim[dim].stride * size;
 116           sstride[n] = array->dim[dim].stride * size;
 117
 118           hstride[n] = h->dim[n].stride;
 119           n++;
 120         }
 121     }
 122   if (sstride[0] == 0)
 123     sstride[0] = size;
 124   if (rstride[0] == 0)
 125     rstride[0] = size;
 126   if (hstride[0] == 0)
 127     hstride[0] = 1;
 128
 129   dim = GFC_DESCRIPTOR_RANK (array);
 130   rstride0 = rstride[0];
 131   sstride0 = sstride[0];
 132   hstride0 = hstride[0];
 133   rptr = ret->data;
 134   sptr = array->data;
 135   hptr = h->data;
 136
 137   while (rptr)
 138     {
 139       /* Do the shift for this dimension.  */
 140       sh = *hptr;
 141       delta = (sh >= 0) ? sh: -sh;
 142       if (sh > 0)
 143         {
 144           src = &sptr[delta * soffset];
 145           dest = rptr;
 146         }
 147       else
 148         {
 149           src = sptr;
 150           dest = &rptr[delta * roffset];
 151         }
 152       for (n = 0; n < len - delta; n++)
 153         {
 154           memcpy (dest, src, size);
 155           dest += roffset;
 156           src += soffset;
 157         }
 158       if (sh < 0)
 159         dest = rptr;
 160       n = delta;
 161
 162       while (n--)
 163         {
 164           memcpy (dest, pbound, size);
 165           dest += roffset;
 166         }
 167
 168       /* Advance to the next section.  */
 169       rptr += rstride0;
 170       sptr += sstride0;
 171       hptr += hstride0;
 172       count[0]++;
 173       n = 0;
 174       while (count[n] == extent[n])
 175         {
 176           /* When we get to the end of a dimension, reset it and increment
 177              the next dimension.  */
 178           count[n] = 0;
 179           /* We could precalculate these products, but this is a less
 180              frequently used path so proabably not worth it.  */
 181           rptr -= rstride[n] * extent[n];
 182           sptr -= sstride[n] * extent[n];
 183           hptr -= hstride[n] * extent[n];
 184           n++;
 185           if (n >= dim - 1)
 186             {
 187               /* Break out of the loop.  */
 188               rptr = NULL;
 189               break;
 190             }
 191           else
 192             {
 193               count[n]++;
 194               rptr += rstride[n];
 195               sptr += sstride[n];
 196               hptr += hstride[n];
 197             }
 198         }
 199     }
 200 }