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->offset = 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       if (( sh >= 0 ? sh : -sh ) > len)
 162         {
 163           delta = len;
 164           sh = len;
 165         }
 166       else
 167         delta = (sh >= 0) ? sh: -sh;
 168
 169       if (sh > 0)
 170         {
 171           src = &sptr[delta * soffset];
 172           dest = rptr;
 173         }
 174       else
 175         {
 176           src = sptr;
 177           dest = &rptr[delta * roffset];
 178         }
 179       for (n = 0; n < len - delta; n++)
 180         {
 181           memcpy (dest, src, size);
 182           dest += roffset;
 183           src += soffset;
 184         }
 185       if (sh < 0)
 186         dest = rptr;
 187       n = delta;
 188
 189       while (n--)
 190         {
 191           memcpy (dest, pbound, size);
 192           dest += roffset;
 193         }
 194
 195       /* Advance to the next section.  */
 196       rptr += rstride0;
 197       sptr += sstride0;
 198       hptr += hstride0;
 199       count[0]++;
 200       n = 0;
 201       while (count[n] == extent[n])
 202         {
 203           /* When we get to the end of a dimension, reset it and increment
 204              the next dimension.  */
 205           count[n] = 0;
 206           /* We could precalculate these products, but this is a less
 207              frequently used path so proabably not worth it.  */
 208           rptr -= rstride[n] * extent[n];
 209           sptr -= sstride[n] * extent[n];
 210           hptr -= hstride[n] * extent[n];
 211           n++;
 212           if (n >= dim - 1)
 213             {
 214               /* Break out of the loop.  */
 215               rptr = NULL;
 216               break;
 217             }
 218           else
 219             {
 220               count[n]++;
 221               rptr += rstride[n];
 222               sptr += sstride[n];
 223               hptr += hstride[n];
 224             }
 225         }
 226     }
 227 }