1 /* Generic implementation of the RESHAPE intrinsic
2 Copyright 2002, 2006 Free Software Foundation, Inc.
3 Contributed by Paul Brook <paul@nowt.org>
5 This file is part of the GNU Fortran 95 runtime library (libgfortran).
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.
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
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.
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. */
35 #include "libgfortran.h"
37 typedef GFC_ARRAY_DESCRIPTOR(1, index_type) shape_type;
38 typedef GFC_ARRAY_DESCRIPTOR(GFC_MAX_DIMENSIONS, char) parray;
41 reshape_internal (parray *ret, parray *source, shape_type *shape,
42 parray *pad, shape_type *order, index_type size)
44 /* r.* indicates the return array. */
45 index_type rcount[GFC_MAX_DIMENSIONS];
46 index_type rextent[GFC_MAX_DIMENSIONS];
47 index_type rstride[GFC_MAX_DIMENSIONS];
54 /* s.* indicates the source array. */
55 index_type scount[GFC_MAX_DIMENSIONS];
56 index_type sextent[GFC_MAX_DIMENSIONS];
57 index_type sstride[GFC_MAX_DIMENSIONS];
62 /* p.* indicates the pad array. */
63 index_type pcount[GFC_MAX_DIMENSIONS];
64 index_type pextent[GFC_MAX_DIMENSIONS];
65 index_type pstride[GFC_MAX_DIMENSIONS];
75 if (ret->data == NULL)
77 rdim = shape->dim[0].ubound - shape->dim[0].lbound + 1;
79 for (n = 0; n < rdim; n++)
81 ret->dim[n].lbound = 0;
82 rex = shape->data[n * shape->dim[0].stride];
83 ret->dim[n].ubound = rex - 1;
84 ret->dim[n].stride = rs;
88 ret->data = internal_malloc_size ( rs * size );
89 ret->dtype = (source->dtype & ~GFC_DTYPE_RANK_MASK) | rdim;
93 rdim = GFC_DESCRIPTOR_RANK (ret);
97 for (n = 0; n < rdim; n++)
100 dim = order->data[n * order->dim[0].stride] - 1;
105 rstride[n] = ret->dim[dim].stride;
106 rextent[n] = ret->dim[dim].ubound + 1 - ret->dim[dim].lbound;
108 if (rextent[n] != shape->data[dim * shape->dim[0].stride])
109 runtime_error ("shape and target do not conform");
111 if (rsize == rstride[n])
119 sdim = GFC_DESCRIPTOR_RANK (source);
122 for (n = 0; n < sdim; n++)
125 sstride[n] = source->dim[n].stride;
126 sextent[n] = source->dim[n].ubound + 1 - source->dim[n].lbound;
133 if (ssize == sstride[n])
141 pdim = GFC_DESCRIPTOR_RANK (pad);
144 for (n = 0; n < pdim; n++)
147 pstride[n] = pad->dim[n].stride;
148 pextent[n] = pad->dim[n].ubound + 1 - pad->dim[n].lbound;
155 if (psize == pstride[n])
170 if (rsize != 0 && ssize != 0 && psize != 0)
175 reshape_packed (ret->data, rsize, source->data, ssize,
176 pad ? pad->data : NULL, psize);
180 src = sptr = source->data;
181 rstride0 = rstride[0] * size;
182 sstride0 = sstride[0] * size;
184 if (sempty && pempty)
189 /* Switch immediately to the pad array. */
193 for (dim = 0; dim < pdim; dim++)
195 scount[dim] = pcount[dim];
196 sextent[dim] = pextent[dim];
197 sstride[dim] = pstride[dim];
198 sstride0 = sstride[0] * size;
204 /* Select between the source and pad arrays. */
205 memcpy(rptr, src, size);
206 /* Advance to the next element. */
212 /* Advance to the next destination element. */
214 while (rcount[n] == rextent[n])
216 /* When we get to the end of a dimension, reset it and increment
217 the next dimension. */
219 /* We could precalculate these products, but this is a less
220 frequently used path so probably not worth it. */
221 rptr -= rstride[n] * rextent[n] * size;
225 /* Break out of the loop. */
232 rptr += rstride[n] * size;
236 /* Advance to the next source element. */
238 while (scount[n] == sextent[n])
240 /* When we get to the end of a dimension, reset it and increment
241 the next dimension. */
243 /* We could precalculate these products, but this is a less
244 frequently used path so probably not worth it. */
245 src -= sstride[n] * sextent[n] * size;
251 /* Switch to the pad array. */
254 for (dim = 0; dim < pdim; dim++)
256 scount[dim] = pcount[dim];
257 sextent[dim] = pextent[dim];
258 sstride[dim] = pstride[dim];
259 sstride0 = sstride[0] * size;
262 /* We now start again from the beginning of the pad array. */
269 src += sstride[n] * size;
275 extern void reshape (parray *, parray *, shape_type *, parray *, shape_type *);
276 export_proto(reshape);
279 reshape (parray *ret, parray *source, shape_type *shape, parray *pad,
282 reshape_internal (ret, source, shape, pad, order,
283 GFC_DESCRIPTOR_SIZE (source));
286 extern void reshape_char (parray *, GFC_INTEGER_4, parray *, shape_type *,
287 parray *, shape_type *, GFC_INTEGER_4,
289 export_proto(reshape_char);
292 reshape_char (parray *ret, GFC_INTEGER_4 ret_length __attribute__((unused)),
293 parray *source, shape_type *shape, parray *pad,
294 shape_type *order, GFC_INTEGER_4 source_length,
295 GFC_INTEGER_4 pad_length __attribute__((unused)))
297 reshape_internal (ret, source, shape, pad, order, source_length);