libgfortran/m4/cshift1.m4

   1 `/* Implementation of the CSHIFT intrinsic
   2    Copyright 2003 Free Software Foundation, Inc.
   3    Contributed by Feng Wang <wf_cs@yahoo.com>
   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 Ligbfortran 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., 51 Franklin Street, Fifth Floor,
  29 Boston, MA 02110-1301, 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 void
  39 cshift1 (gfc_array_char * ret, const gfc_array_char * array,
  40          const atype * h, const atype_name * pwhich, index_type size)
  41 {
  42   /* r.* indicates the return array.  */
  43   index_type rstride[GFC_MAX_DIMENSIONS];
  44   index_type rstride0;
  45   index_type roffset;
  46   char *rptr;
  47   char *dest;
  48   /* s.* indicates the source array.  */
  49   index_type sstride[GFC_MAX_DIMENSIONS];
  50   index_type sstride0;
  51   index_type soffset;
  52   const char *sptr;
  53   const char *src;
  54   /* h.* indicates the shift array.  */
  55   index_type hstride[GFC_MAX_DIMENSIONS];
  56   index_type hstride0;
  57   const atype_name *hptr;
  58
  59   index_type count[GFC_MAX_DIMENSIONS];
  60   index_type extent[GFC_MAX_DIMENSIONS];
  61   index_type dim;
  62   index_type len;
  63   index_type n;
  64   int which;
  65   atype_name sh;
  66
  67   if (pwhich)
  68     which = *pwhich - 1;
  69   else
  70     which = 0;
  71
  72   if (which < 0 || (which + 1) > GFC_DESCRIPTOR_RANK (array))
  73     runtime_error ("Argument 'DIM' is out of range in call to 'CSHIFT'");
  74
  75   if (ret->data == NULL)
  76     {
  77       int i;
  78
  79       ret->data = internal_malloc_size (size * size0 ((array_t *)array));
  80       ret->offset = 0;
  81       ret->dtype = array->dtype;
  82       for (i = 0; i < GFC_DESCRIPTOR_RANK (array); i++)
  83         {
  84           ret->dim[i].lbound = 0;
  85           ret->dim[i].ubound = array->dim[i].ubound - array->dim[i].lbound;
  86
  87           if (i == 0)
  88             ret->dim[i].stride = 1;
  89           else
  90             ret->dim[i].stride = (ret->dim[i-1].ubound + 1) * ret->dim[i-1].stride;
  91         }
  92     }
  93
  94   extent[0] = 1;
  95   count[0] = 0;
  96   n = 0;
  97
  98   /* Initialized for avoiding compiler warnings.  */
  99   roffset = size;
 100   soffset = size;
 101   len = 0;
 102
 103   for (dim = 0; dim < GFC_DESCRIPTOR_RANK (array); dim++)
 104     {
 105       if (dim == which)
 106         {
 107           roffset = ret->dim[dim].stride * size;
 108           if (roffset == 0)
 109             roffset = size;
 110           soffset = array->dim[dim].stride * size;
 111           if (soffset == 0)
 112             soffset = size;
 113           len = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
 114         }
 115       else
 116         {
 117           count[n] = 0;
 118           extent[n] = array->dim[dim].ubound + 1 - array->dim[dim].lbound;
 119           rstride[n] = ret->dim[dim].stride * size;
 120           sstride[n] = array->dim[dim].stride * size;
 121
 122           hstride[n] = h->dim[n].stride;
 123           n++;
 124         }
 125     }
 126   if (sstride[0] == 0)
 127     sstride[0] = size;
 128   if (rstride[0] == 0)
 129     rstride[0] = size;
 130   if (hstride[0] == 0)
 131     hstride[0] = 1;
 132
 133   dim = GFC_DESCRIPTOR_RANK (array);
 134   rstride0 = rstride[0];
 135   sstride0 = sstride[0];
 136   hstride0 = hstride[0];
 137   rptr = ret->data;
 138   sptr = array->data;
 139   hptr = h->data;
 140
 141   while (rptr)
 142     {
 143       /* Do the shift for this dimension.  */
 144       sh = *hptr;
 145       sh = (div (sh, len)).rem;
 146       if (sh < 0)
 147         sh += len;
 148
 149       src = &sptr[sh * soffset];
 150       dest = rptr;
 151
 152       for (n = 0; n < len; n++)
 153         {
 154           memcpy (dest, src, size);
 155           dest += roffset;
 156           if (n == len - sh - 1)
 157             src = sptr;
 158           else
 159             src += soffset;
 160         }
 161
 162       /* Advance to the next section.  */
 163       rptr += rstride0;
 164       sptr += sstride0;
 165       hptr += hstride0;
 166       count[0]++;
 167       n = 0;
 168       while (count[n] == extent[n])
 169         {
 170           /* When we get to the end of a dimension, reset it and increment
 171              the next dimension.  */
 172           count[n] = 0;
 173           /* We could precalculate these products, but this is a less
 174              frequently used path so proabably not worth it.  */
 175           rptr -= rstride[n] * extent[n];
 176           sptr -= sstride[n] * extent[n];
 177           hptr -= hstride[n] * extent[n];
 178           n++;
 179           if (n >= dim - 1)
 180             {
 181               /* Break out of the loop.  */
 182               rptr = NULL;
 183               break;
 184             }
 185           else
 186             {
 187               count[n]++;
 188               rptr += rstride[n];
 189               sptr += sstride[n];
 190               hptr += hstride[n];
 191             }
 192         }
 193     }
 194 }
 195
 196 void cshift1_`'atype_kind (gfc_array_char *, const gfc_array_char *,
 197                            const atype *, const atype_name *);
 198 export_proto(cshift1_`'atype_kind);
 199
 200 void
 201 cshift1_`'atype_kind (gfc_array_char * ret,
 202                       const gfc_array_char * array,
 203                       const atype * h, const atype_name * pwhich)
 204 {
 205   cshift1 (ret, array, h, pwhich, GFC_DESCRIPTOR_SIZE (array));
 206 }
 207
 208 void cshift1_`'atype_kind`'_char (gfc_array_char * ret, GFC_INTEGER_4,
 209                                   const gfc_array_char * array,
 210                                   const atype * h, const atype_name * pwhich,
 211                                   GFC_INTEGER_4);
 212 export_proto(cshift1_`'atype_kind`'_char);
 213
 214 void
 215 cshift1_`'atype_kind`'_char (gfc_array_char * ret,
 216                              GFC_INTEGER_4 ret_length __attribute__((unused)),
 217                              const gfc_array_char * array,
 218                              const atype * h, const atype_name * pwhich,
 219                              GFC_INTEGER_4 array_length)
 220 {
 221   cshift1 (ret, array, h, pwhich, array_length);
 222 }