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 (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 (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
  99   if (ret->data == NULL)
 100     {
 101       int i;
 102
 103       ret->data = internal_malloc_size (size * size0 ((array_t *)array));
 104       ret->base = 0;
 105       ret->dtype = array->dtype;
 106       for (i = 0; i < GFC_DESCRIPTOR_RANK (array); i++)
 107         {
 108           ret->dim[i].lbound = 0;
 109           ret->dim[i].ubound = array->dim[i].ubound - array->dim[i].lbound;
 110
 111           if (i == 0)
 112             ret->dim[i].stride = 1;
 113           else
 114             ret->dim[i].stride = (ret->dim[i-1].ubound + 1) * ret->dim[i-1].stride;
 115         }
 116     }
 117
 118   n = 0;
 119   for (dim = 0; dim < GFC_DESCRIPTOR_RANK (array); dim++)
 120     {
 121       if (dim == which)
 122         {
 123           roffset = ret->dim[dim].stride * size;
 124           if (roffset == 0)
 125             roffset = size;
 126           soffset = array->dim[dim].stride * size;
 127           if (soffset == 0)
 128             soffset = size;
 129           len = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
 130         }
 131       else
 132         {
 133           count[n] = 0;
 134           extent[n] = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
 135           rstride[n] = ret->dim[dim].stride * size;
 136           sstride[n] = array->dim[dim].stride * size;
 137
 138           hstride[n] = h->dim[n].stride * size;
 139           n++;
 140         }
 141     }
 142   if (sstride[0] == 0)
 143     sstride[0] = size;
 144   if (rstride[0] == 0)
 145     rstride[0] = size;
 146   if (hstride[0] == 0)
 147     hstride[0] = 1;
 148
 149   dim = GFC_DESCRIPTOR_RANK (array);
 150   rstride0 = rstride[0];
 151   sstride0 = sstride[0];
 152   hstride0 = hstride[0];
 153   rptr = ret->data;
 154   sptr = array->data;
 155   hptr = h->data;
 156
 157   while (rptr)
 158     {
 159       /* Do the shift for this dimension.  */
 160       sh = *hptr;
 161       delta = (sh >= 0) ? sh: -sh;
 162       if (sh > 0)
 163         {
 164           src = &sptr[delta * soffset];
 165           dest = rptr;
 166         }
 167       else
 168         {
 169           src = sptr;
 170           dest = &rptr[delta * roffset];
 171         }
 172       for (n = 0; n < len - delta; n++)
 173         {
 174           memcpy (dest, src, size);
 175           dest += roffset;
 176           src += soffset;
 177         }
 178       if (sh < 0)
 179         dest = rptr;
 180       n = delta;
 181
 182       while (n--)
 183         {
 184           memcpy (dest, pbound, size);
 185           dest += roffset;
 186         }
 187
 188       /* Advance to the next section.  */
 189       rptr += rstride0;
 190       sptr += sstride0;
 191       hptr += hstride0;
 192       count[0]++;
 193       n = 0;
 194       while (count[n] == extent[n])
 195         {
 196           /* When we get to the end of a dimension, reset it and increment
 197              the next dimension.  */
 198           count[n] = 0;
 199           /* We could precalculate these products, but this is a less
 200              frequently used path so proabably not worth it.  */
 201           rptr -= rstride[n] * extent[n];
 202           sptr -= sstride[n] * extent[n];
 203           hptr -= hstride[n] * extent[n];
 204           n++;
 205           if (n >= dim - 1)
 206             {
 207               /* Break out of the loop.  */
 208               rptr = NULL;
 209               break;
 210             }
 211           else
 212             {
 213               count[n]++;
 214               rptr += rstride[n];
 215               sptr += sstride[n];
 216               hptr += hstride[n];
 217             }
 218         }
 219     }
 220 }