libgfortran/m4/eoshift1.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 (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 include(iparm.m4)dnl
  28
  29 static const char zeros[16] =
  30   {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
  31
  32 extern void __eoshift1_`'atype_kind (const gfc_array_char *,
  33                                      const gfc_array_char *,
  34                                      const atype *, const char *,
  35                                      const atype_name *);
  36 export_proto_np(__eoshift1_`'atype_kind);
  37
  38 void
  39 __eoshift1_`'atype_kind (const gfc_array_char *ret,
  40                          const gfc_array_char *array,
  41                          const atype *h, const char *pbound,
  42                          const atype_name *pwhich)
  43 {
  44   /* r.* indicates the return array.  */
  45   index_type rstride[GFC_MAX_DIMENSIONS - 1];
  46   index_type rstride0;
  47   index_type roffset;
  48   char *rptr;
  49   char *dest;
  50   /* s.* indicates the source array.  */
  51   index_type sstride[GFC_MAX_DIMENSIONS - 1];
  52   index_type sstride0;
  53   index_type soffset;
  54   const char *sptr;
  55   const char *src;
  56 `  /* h.* indicates the shift array.  */'
  57   index_type hstride[GFC_MAX_DIMENSIONS - 1];
  58   index_type hstride0;
  59   const atype_name *hptr;
  60
  61   index_type count[GFC_MAX_DIMENSIONS - 1];
  62   index_type extent[GFC_MAX_DIMENSIONS - 1];
  63   index_type dim;
  64   index_type size;
  65   index_type len;
  66   index_type n;
  67   int which;
  68   atype_name sh;
  69   atype_name delta;
  70
  71   if (pwhich)
  72     which = *pwhich - 1;
  73   else
  74     which = 0;
  75
  76   if (!pbound)
  77     pbound = zeros;
  78
  79   size = GFC_DESCRIPTOR_SIZE (ret);
  80
  81   extent[0] = 1;
  82   count[0] = 0;
  83   size = GFC_DESCRIPTOR_SIZE (array);
  84   n = 0;
  85   for (dim = 0; dim < GFC_DESCRIPTOR_RANK (array); dim++)
  86     {
  87       if (dim == which)
  88         {
  89           roffset = ret->dim[dim].stride * size;
  90           if (roffset == 0)
  91             roffset = size;
  92           soffset = array->dim[dim].stride * size;
  93           if (soffset == 0)
  94             soffset = size;
  95           len = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
  96         }
  97       else
  98         {
  99           count[n] = 0;
 100           extent[n] = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
 101           rstride[n] = ret->dim[dim].stride * size;
 102           sstride[n] = array->dim[dim].stride * size;
 103
 104           hstride[n] = h->dim[n].stride;
 105           n++;
 106         }
 107     }
 108   if (sstride[0] == 0)
 109     sstride[0] = size;
 110   if (rstride[0] == 0)
 111     rstride[0] = size;
 112   if (hstride[0] == 0)
 113     hstride[0] = 1;
 114
 115   dim = GFC_DESCRIPTOR_RANK (array);
 116   rstride0 = rstride[0];
 117   sstride0 = sstride[0];
 118   hstride0 = hstride[0];
 119   rptr = ret->data;
 120   sptr = array->data;
 121   hptr = h->data;
 122
 123   while (rptr)
 124     {
 125 `      /* Do the shift for this dimension.  */'
 126       sh = *hptr;
 127       delta = (sh >= 0) ? sh: -sh;
 128       if (sh > 0)
 129         {
 130           src = &sptr[delta * soffset];
 131           dest = rptr;
 132         }
 133       else
 134         {
 135           src = sptr;
 136           dest = &rptr[delta * roffset];
 137         }
 138       for (n = 0; n < len - delta; n++)
 139         {
 140           memcpy (dest, src, size);
 141           dest += roffset;
 142           src += soffset;
 143         }
 144       if (sh < 0)
 145         dest = rptr;
 146       n = delta;
 147
 148       while (n--)
 149         {
 150           memcpy (dest, pbound, size);
 151           dest += roffset;
 152         }
 153
 154       /* Advance to the next section.  */
 155       rptr += rstride0;
 156       sptr += sstride0;
 157       hptr += hstride0;
 158       count[0]++;
 159       n = 0;
 160       while (count[n] == extent[n])
 161         {
 162           /* When we get to the end of a dimension, reset it and increment
 163              the next dimension.  */
 164           count[n] = 0;
 165           /* We could precalculate these products, but this is a less
 166              frequently used path so proabably not worth it.  */
 167           rptr -= rstride[n] * extent[n];
 168           sptr -= sstride[n] * extent[n];
 169           hptr -= hstride[n] * extent[n];
 170           n++;
 171           if (n >= dim - 1)
 172             {
 173               /* Break out of the loop.  */
 174               rptr = NULL;
 175               break;
 176             }
 177           else
 178             {
 179               count[n]++;
 180               rptr += rstride[n];
 181               sptr += sstride[n];
 182               hptr += hstride[n];
 183             }
 184         }
 185     }
 186 }