libgfortran/m4/eoshift3.m4

   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 (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 include(iparm.m4)dnl
  37
  38 static const char zeros[16] =
  39   {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
  40
  41 extern void eoshift3_`'atype_kind (gfc_array_char *, gfc_array_char *,
  42                                      atype *, const gfc_array_char *,
  43                                      atype_name *);
  44 export_proto(eoshift3_`'atype_kind);
  45
  46 void
  47 eoshift3_`'atype_kind (gfc_array_char *ret, gfc_array_char *array,
  48                        atype *h, const gfc_array_char *bound,
  49                        atype_name *pwhich)
  50 {
  51   /* r.* indicates the return array.  */
  52   index_type rstride[GFC_MAX_DIMENSIONS];
  53   index_type rstride0;
  54   index_type roffset;
  55   char *rptr;
  56   char *dest;
  57   /* s.* indicates the source array.  */
  58   index_type sstride[GFC_MAX_DIMENSIONS];
  59   index_type sstride0;
  60   index_type soffset;
  61   const char *sptr;
  62   const char *src;
  63 `  /* h.* indicates the shift array.  */'
  64   index_type hstride[GFC_MAX_DIMENSIONS];
  65   index_type hstride0;
  66   const atype_name *hptr;
  67   /* b.* indicates the bound array.  */
  68   index_type bstride[GFC_MAX_DIMENSIONS];
  69   index_type bstride0;
  70   const char *bptr;
  71
  72   index_type count[GFC_MAX_DIMENSIONS];
  73   index_type extent[GFC_MAX_DIMENSIONS];
  74   index_type dim;
  75   index_type size;
  76   index_type len;
  77   index_type n;
  78   int which;
  79   atype_name sh;
  80   atype_name delta;
  81
  82   if (pwhich)
  83     which = *pwhich - 1;
  84   else
  85     which = 0;
  86
  87   size = GFC_DESCRIPTOR_SIZE (ret);
  88
  89   extent[0] = 1;
  90   count[0] = 0;
  91   size = GFC_DESCRIPTOR_SIZE (array);
  92   n = 0;
  93   for (dim = 0; dim < GFC_DESCRIPTOR_RANK (array); dim++)
  94     {
  95       if (dim == which)
  96         {
  97           roffset = ret->dim[dim].stride * size;
  98           if (roffset == 0)
  99             roffset = size;
 100           soffset = array->dim[dim].stride * size;
 101           if (soffset == 0)
 102             soffset = size;
 103           len = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
 104         }
 105       else
 106         {
 107           count[n] = 0;
 108           extent[n] = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
 109           rstride[n] = ret->dim[dim].stride * size;
 110           sstride[n] = array->dim[dim].stride * size;
 111
 112           hstride[n] = h->dim[n].stride;
 113           if (bound)
 114             bstride[n] = bound->dim[n].stride;
 115           else
 116             bstride[n] = 0;
 117           n++;
 118         }
 119     }
 120   if (sstride[0] == 0)
 121     sstride[0] = size;
 122   if (rstride[0] == 0)
 123     rstride[0] = size;
 124   if (hstride[0] == 0)
 125     hstride[0] = 1;
 126   if (bound && bstride[0] == 0)
 127     bstride[0] = size;
 128
 129   dim = GFC_DESCRIPTOR_RANK (array);
 130   rstride0 = rstride[0];
 131   sstride0 = sstride[0];
 132   hstride0 = hstride[0];
 133   bstride0 = bstride[0];
 134   rptr = ret->data;
 135   sptr = array->data;
 136   hptr = h->data;
 137   if (bound)
 138     bptr = bound->data;
 139   else
 140     bptr = zeros;
 141
 142   while (rptr)
 143     {
 144 `      /* Do the shift for this dimension.  */'
 145       sh = *hptr;
 146       delta = (sh >= 0) ? sh: -sh;
 147       if (sh > 0)
 148         {
 149           src = &sptr[delta * soffset];
 150           dest = rptr;
 151         }
 152       else
 153         {
 154           src = sptr;
 155           dest = &rptr[delta * roffset];
 156         }
 157       for (n = 0; n < len - delta; n++)
 158         {
 159           memcpy (dest, src, size);
 160           dest += roffset;
 161           src += soffset;
 162         }
 163       if (sh < 0)
 164         dest = rptr;
 165       n = delta;
 166
 167       while (n--)
 168         {
 169           memcpy (dest, bptr, size);
 170           dest += roffset;
 171         }
 172
 173       /* Advance to the next section.  */
 174       rptr += rstride0;
 175       sptr += sstride0;
 176       hptr += hstride0;
 177       bptr += bstride0;
 178       count[0]++;
 179       n = 0;
 180       while (count[n] == extent[n])
 181         {
 182           /* When we get to the end of a dimension, reset it and increment
 183              the next dimension.  */
 184           count[n] = 0;
 185           /* We could precalculate these products, but this is a less
 186              frequently used path so proabably not worth it.  */
 187           rptr -= rstride[n] * extent[n];
 188           sptr -= sstride[n] * extent[n];
 189           hptr -= hstride[n] * extent[n];
 190           bptr -= bstride[n] * extent[n];
 191           n++;
 192           if (n >= dim - 1)
 193             {
 194               /* Break out of the loop.  */
 195               rptr = NULL;
 196               break;
 197             }
 198           else
 199             {
 200               count[n]++;
 201               rptr += rstride[n];
 202               sptr += sstride[n];
 203               hptr += hstride[n];
 204               bptr += bstride[n];
 205             }
 206         }
 207     }
 208 }