libgfortran/intrinsics/spread_generic.c

   1 /* Generic implementation of the SPREAD intrinsic
   2    Copyright 2002, 2005, 2006, 2007 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 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 "libgfortran.h"
  32 #include <stdlib.h>
  33 #include <assert.h>
  34 #include <string.h>
  35
  36 static void
  37 spread_internal (gfc_array_char *ret, const gfc_array_char *source,
  38                  const index_type *along, const index_type *pncopies,
  39                  index_type size)
  40 {
  41   /* r.* indicates the return array.  */
  42   index_type rstride[GFC_MAX_DIMENSIONS];
  43   index_type rstride0;
  44   index_type rdelta = 0;
  45   index_type rrank;
  46   index_type rs;
  47   char *rptr;
  48   char *dest;
  49   /* s.* indicates the source array.  */
  50   index_type sstride[GFC_MAX_DIMENSIONS];
  51   index_type sstride0;
  52   index_type srank;
  53   const char *sptr;
  54
  55   index_type count[GFC_MAX_DIMENSIONS];
  56   index_type extent[GFC_MAX_DIMENSIONS];
  57   index_type n;
  58   index_type dim;
  59   index_type ncopies;
  60
  61   srank = GFC_DESCRIPTOR_RANK(source);
  62
  63   rrank = srank + 1;
  64   if (rrank > GFC_MAX_DIMENSIONS)
  65     runtime_error ("return rank too large in spread()");
  66
  67   if (*along > rrank)
  68       runtime_error ("dim outside of rank in spread()");
  69
  70   ncopies = *pncopies;
  71
  72   if (ret->data == NULL)
  73     {
  74       /* The front end has signalled that we need to populate the
  75          return array descriptor.  */
  76       ret->dtype = (source->dtype & ~GFC_DTYPE_RANK_MASK) | rrank;
  77       dim = 0;
  78       rs = 1;
  79       for (n = 0; n < rrank; n++)
  80         {
  81           ret->dim[n].stride = rs;
  82           ret->dim[n].lbound = 0;
  83           if (n == *along - 1)
  84             {
  85               ret->dim[n].ubound = ncopies - 1;
  86               rdelta = rs * size;
  87               rs *= ncopies;
  88             }
  89           else
  90             {
  91               count[dim] = 0;
  92               extent[dim] = source->dim[dim].ubound + 1
  93                 - source->dim[dim].lbound;
  94               sstride[dim] = source->dim[dim].stride * size;
  95               rstride[dim] = rs * size;
  96
  97               ret->dim[n].ubound = extent[dim]-1;
  98               rs *= extent[dim];
  99               dim++;
 100             }
 101         }
 102       ret->offset = 0;
 103       if (rs > 0)
 104         ret->data = internal_malloc_size (rs * size);
 105       else
 106         {
 107           ret->data = internal_malloc_size (1);
 108           return;
 109         }
 110     }
 111   else
 112     {
 113       int zero_sized;
 114
 115       zero_sized = 0;
 116
 117       dim = 0;
 118       if (GFC_DESCRIPTOR_RANK(ret) != rrank)
 119         runtime_error ("rank mismatch in spread()");
 120
 121       if (compile_options.bounds_check)
 122         {
 123           for (n = 0; n < rrank; n++)
 124             {
 125               index_type ret_extent;
 126
 127               ret_extent = ret->dim[n].ubound + 1 - ret->dim[n].lbound;
 128               if (n == *along - 1)
 129                 {
 130                   rdelta = ret->dim[n].stride * size;
 131
 132                   if (ret_extent != ncopies)
 133                     runtime_error("Incorrect extent in return value of SPREAD"
 134                                   " intrinsic in dimension %ld: is %ld,"
 135                                   " should be %ld", (long int) n+1,
 136                                   (long int) ret_extent, (long int) ncopies);
 137                 }
 138               else
 139                 {
 140                   count[dim] = 0;
 141                   extent[dim] = source->dim[dim].ubound + 1
 142                     - source->dim[dim].lbound;
 143                   if (ret_extent != extent[dim])
 144                     runtime_error("Incorrect extent in return value of SPREAD"
 145                                   " intrinsic in dimension %ld: is %ld,"
 146                                   " should be %ld", (long int) n+1,
 147                                   (long int) ret_extent,
 148                                   (long int) extent[dim]);
 149
 150                   if (extent[dim] <= 0)
 151                     zero_sized = 1;
 152                   sstride[dim] = source->dim[dim].stride * size;
 153                   rstride[dim] = ret->dim[n].stride * size;
 154                   dim++;
 155                 }
 156             }
 157         }
 158       else
 159         {
 160           for (n = 0; n < rrank; n++)
 161             {
 162               if (n == *along - 1)
 163                 {
 164                   rdelta = ret->dim[n].stride * size;
 165                 }
 166               else
 167                 {
 168                   count[dim] = 0;
 169                   extent[dim] = source->dim[dim].ubound + 1
 170                     - source->dim[dim].lbound;
 171                   if (extent[dim] <= 0)
 172                     zero_sized = 1;
 173                   sstride[dim] = source->dim[dim].stride * size;
 174                   rstride[dim] = ret->dim[n].stride * size;
 175                   dim++;
 176                 }
 177             }
 178         }
 179
 180       if (zero_sized)
 181         return;
 182
 183       if (sstride[0] == 0)
 184         sstride[0] = size;
 185     }
 186   sstride0 = sstride[0];
 187   rstride0 = rstride[0];
 188   rptr = ret->data;
 189   sptr = source->data;
 190
 191   while (sptr)
 192     {
 193       /* Spread this element.  */
 194       dest = rptr;
 195       for (n = 0; n < ncopies; n++)
 196         {
 197           memcpy (dest, sptr, size);
 198           dest += rdelta;
 199         }
 200       /* Advance to the next element.  */
 201       sptr += sstride0;
 202       rptr += rstride0;
 203       count[0]++;
 204       n = 0;
 205       while (count[n] == extent[n])
 206         {
 207           /* When we get to the end of a dimension, reset it and increment
 208              the next dimension.  */
 209           count[n] = 0;
 210           /* We could precalculate these products, but this is a less
 211              frequently used path so probably not worth it.  */
 212           sptr -= sstride[n] * extent[n];
 213           rptr -= rstride[n] * extent[n];
 214           n++;
 215           if (n >= srank)
 216             {
 217               /* Break out of the loop.  */
 218               sptr = NULL;
 219               break;
 220             }
 221           else
 222             {
 223               count[n]++;
 224               sptr += sstride[n];
 225               rptr += rstride[n];
 226             }
 227         }
 228     }
 229 }
 230
 231 /* This version of spread_internal treats the special case of a scalar
 232    source.  This is much simpler than the more general case above.  */
 233
 234 static void
 235 spread_internal_scalar (gfc_array_char *ret, const char *source,
 236                         const index_type *along, const index_type *pncopies,
 237                         index_type size)
 238 {
 239   int n;
 240   int ncopies = *pncopies;
 241   char * dest;
 242
 243   if (GFC_DESCRIPTOR_RANK (ret) != 1)
 244     runtime_error ("incorrect destination rank in spread()");
 245
 246   if (*along > 1)
 247     runtime_error ("dim outside of rank in spread()");
 248
 249   if (ret->data == NULL)
 250     {
 251       ret->data = internal_malloc_size (ncopies * size);
 252       ret->offset = 0;
 253       ret->dim[0].stride = 1;
 254       ret->dim[0].lbound = 0;
 255       ret->dim[0].ubound = ncopies - 1;
 256     }
 257   else
 258     {
 259       if (ncopies - 1 > (ret->dim[0].ubound - ret->dim[0].lbound)
 260                            / ret->dim[0].stride)
 261         runtime_error ("dim too large in spread()");
 262     }
 263
 264   for (n = 0; n < ncopies; n++)
 265     {
 266       dest = (char*)(ret->data + n*size*ret->dim[0].stride);
 267       memcpy (dest , source, size);
 268     }
 269 }
 270
 271 extern void spread (gfc_array_char *, const gfc_array_char *,
 272                     const index_type *, const index_type *);
 273 export_proto(spread);
 274
 275 void
 276 spread (gfc_array_char *ret, const gfc_array_char *source,
 277         const index_type *along, const index_type *pncopies)
 278 {
 279   spread_internal (ret, source, along, pncopies, GFC_DESCRIPTOR_SIZE (source));
 280 }
 281
 282 extern void spread_char (gfc_array_char *, GFC_INTEGER_4,
 283                          const gfc_array_char *, const index_type *,
 284                          const index_type *, GFC_INTEGER_4);
 285 export_proto(spread_char);
 286
 287 void
 288 spread_char (gfc_array_char *ret,
 289              GFC_INTEGER_4 ret_length __attribute__((unused)),
 290              const gfc_array_char *source, const index_type *along,
 291              const index_type *pncopies, GFC_INTEGER_4 source_length)
 292 {
 293   spread_internal (ret, source, along, pncopies, source_length);
 294 }
 295
 296 /* The following are the prototypes for the versions of spread with a
 297    scalar source.  */
 298
 299 extern void spread_scalar (gfc_array_char *, const char *,
 300                            const index_type *, const index_type *);
 301 export_proto(spread_scalar);
 302
 303 void
 304 spread_scalar (gfc_array_char *ret, const char *source,
 305                const index_type *along, const index_type *pncopies)
 306 {
 307   if (!ret->dtype)
 308     runtime_error ("return array missing descriptor in spread()");
 309   spread_internal_scalar (ret, source, along, pncopies, GFC_DESCRIPTOR_SIZE (ret));
 310 }
 311
 312
 313 extern void spread_char_scalar (gfc_array_char *, GFC_INTEGER_4,
 314                                 const char *, const index_type *,
 315                                 const index_type *, GFC_INTEGER_4);
 316 export_proto(spread_char_scalar);
 317
 318 void
 319 spread_char_scalar (gfc_array_char *ret,
 320                     GFC_INTEGER_4 ret_length __attribute__((unused)),
 321                     const char *source, const index_type *along,
 322                     const index_type *pncopies, GFC_INTEGER_4 source_length)
 323 {
 324   if (!ret->dtype)
 325     runtime_error ("return array missing descriptor in spread()");
 326   spread_internal_scalar (ret, source, along, pncopies, source_length);
 327 }
 328