libgfortran/generated/eoshift3_8.c

   1 /* Implementation of the EOSHIFT intrinsic
   2    Copyright 2002 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 (libgfor).
   6
   7 Libgfor is free software; you can redistribute it and/or
   8 modify it under the terms of the GNU Lesser General Public
   9 License as published by the Free Software Foundation; either
  10 version 2.1 of the License, or (at your option) any later version.
  11
  12 Ligbfor is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU Lesser General Public License for more details.
  16
  17 You should have received a copy of the GNU Lesser General Public
  18 License along with libgfor; see the file COPYING.LIB.  If not,
  19 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 #include "config.h"
  23 #include <stdlib.h>
  24 #include <assert.h>
  25 #include <string.h>
  26 #include "libgfortran.h"
  27
  28 static const char zeros[16] =
  29   {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
  30
  31 extern void eoshift3_8 (gfc_array_char *, gfc_array_char *,
  32                                      gfc_array_i8 *, const gfc_array_char *,
  33                                      GFC_INTEGER_8 *);
  34 export_proto(eoshift3_8);
  35
  36 void
  37 eoshift3_8 (gfc_array_char *ret, gfc_array_char *array,
  38                        gfc_array_i8 *h, const gfc_array_char *bound,
  39                        GFC_INTEGER_8 *pwhich)
  40 {
  41   /* r.* indicates the return array.  */
  42   index_type rstride[GFC_MAX_DIMENSIONS - 1];
  43   index_type rstride0;
  44   index_type roffset;
  45   char *rptr;
  46   char *dest;
  47   /* s.* indicates the source array.  */
  48   index_type sstride[GFC_MAX_DIMENSIONS - 1];
  49   index_type sstride0;
  50   index_type soffset;
  51   const char *sptr;
  52   const char *src;
  53   /* h.* indicates the shift array.  */
  54   index_type hstride[GFC_MAX_DIMENSIONS - 1];
  55   index_type hstride0;
  56   const GFC_INTEGER_8 *hptr;
  57   /* b.* indicates the bound array.  */
  58   index_type bstride[GFC_MAX_DIMENSIONS - 1];
  59   index_type bstride0;
  60   const char *bptr;
  61
  62   index_type count[GFC_MAX_DIMENSIONS - 1];
  63   index_type extent[GFC_MAX_DIMENSIONS - 1];
  64   index_type dim;
  65   index_type size;
  66   index_type len;
  67   index_type n;
  68   int which;
  69   GFC_INTEGER_8 sh;
  70   GFC_INTEGER_8 delta;
  71
  72   if (pwhich)
  73     which = *pwhich - 1;
  74   else
  75     which = 0;
  76
  77   size = GFC_DESCRIPTOR_SIZE (ret);
  78
  79   extent[0] = 1;
  80   count[0] = 0;
  81   size = GFC_DESCRIPTOR_SIZE (array);
  82   n = 0;
  83   for (dim = 0; dim < GFC_DESCRIPTOR_RANK (array); dim++)
  84     {
  85       if (dim == which)
  86         {
  87           roffset = ret->dim[dim].stride * size;
  88           if (roffset == 0)
  89             roffset = size;
  90           soffset = array->dim[dim].stride * size;
  91           if (soffset == 0)
  92             soffset = size;
  93           len = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
  94         }
  95       else
  96         {
  97           count[n] = 0;
  98           extent[n] = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
  99           rstride[n] = ret->dim[dim].stride * size;
 100           sstride[n] = array->dim[dim].stride * size;
 101
 102           hstride[n] = h->dim[n].stride;
 103           if (bound)
 104             bstride[n] = bound->dim[n].stride;
 105           else
 106             bstride[n] = 0;
 107           n++;
 108         }
 109     }
 110   if (sstride[0] == 0)
 111     sstride[0] = size;
 112   if (rstride[0] == 0)
 113     rstride[0] = size;
 114   if (hstride[0] == 0)
 115     hstride[0] = 1;
 116   if (bound && bstride[0] == 0)
 117     bstride[0] = size;
 118
 119   dim = GFC_DESCRIPTOR_RANK (array);
 120   rstride0 = rstride[0];
 121   sstride0 = sstride[0];
 122   hstride0 = hstride[0];
 123   bstride0 = bstride[0];
 124   rptr = ret->data;
 125   sptr = array->data;
 126   hptr = h->data;
 127   if (bound)
 128     bptr = bound->data;
 129   else
 130     bptr = zeros;
 131
 132   while (rptr)
 133     {
 134       /* Do the shift for this dimension.  */
 135       sh = *hptr;
 136       delta = (sh >= 0) ? sh: -sh;
 137       if (sh > 0)
 138         {
 139           src = &sptr[delta * soffset];
 140           dest = rptr;
 141         }
 142       else
 143         {
 144           src = sptr;
 145           dest = &rptr[delta * roffset];
 146         }
 147       for (n = 0; n < len - delta; n++)
 148         {
 149           memcpy (dest, src, size);
 150           dest += roffset;
 151           src += soffset;
 152         }
 153       if (sh < 0)
 154         dest = rptr;
 155       n = delta;
 156
 157       while (n--)
 158         {
 159           memcpy (dest, bptr, size);
 160           dest += roffset;
 161         }
 162
 163       /* Advance to the next section.  */
 164       rptr += rstride0;
 165       sptr += sstride0;
 166       hptr += hstride0;
 167       bptr += bstride0;
 168       count[0]++;
 169       n = 0;
 170       while (count[n] == extent[n])
 171         {
 172           /* When we get to the end of a dimension, reset it and increment
 173              the next dimension.  */
 174           count[n] = 0;
 175           /* We could precalculate these products, but this is a less
 176              frequently used path so proabably not worth it.  */
 177           rptr -= rstride[n] * extent[n];
 178           sptr -= sstride[n] * extent[n];
 179           hptr -= hstride[n] * extent[n];
 180           bptr -= bstride[n] * extent[n];
 181           n++;
 182           if (n >= dim - 1)
 183             {
 184               /* Break out of the loop.  */
 185               rptr = NULL;
 186               break;
 187             }
 188           else
 189             {
 190               count[n]++;
 191               rptr += rstride[n];
 192               sptr += sstride[n];
 193               hptr += hstride[n];
 194               bptr += bstride[n];
 195             }
 196         }
 197     }
 198 }