libgfortran/generated/in_pack_c4.c

   1 /* Helper function for repacking arrays.
   2    Copyright 2003, 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 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., 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
  35
  36 #if defined (HAVE_GFC_COMPLEX_4)
  37
  38 /* Allocates a block of memory with internal_malloc if the array needs
  39    repacking.  */
  40
  41 GFC_COMPLEX_4 *
  42 internal_pack_c4 (gfc_array_c4 * source)
  43 {
  44   index_type count[GFC_MAX_DIMENSIONS];
  45   index_type extent[GFC_MAX_DIMENSIONS];
  46   index_type stride[GFC_MAX_DIMENSIONS];
  47   index_type stride0;
  48   index_type dim;
  49   index_type ssize;
  50   const GFC_COMPLEX_4 *src;
  51   GFC_COMPLEX_4 *dest;
  52   GFC_COMPLEX_4 *destptr;
  53   int n;
  54   int packed;
  55
  56   /* TODO: Investigate how we can figure out if this is a temporary
  57      since the stride=0 thing has been removed from the frontend.  */
  58
  59   dim = GFC_DESCRIPTOR_RANK (source);
  60   ssize = 1;
  61   packed = 1;
  62   for (n = 0; n < dim; n++)
  63     {
  64       count[n] = 0;
  65       stride[n] = source->dim[n].stride;
  66       extent[n] = source->dim[n].ubound + 1 - source->dim[n].lbound;
  67       if (extent[n] <= 0)
  68         {
  69           /* Do nothing.  */
  70           packed = 1;
  71           break;
  72         }
  73
  74       if (ssize != stride[n])
  75         packed = 0;
  76
  77       ssize *= extent[n];
  78     }
  79
  80   if (packed)
  81     return source->data;
  82
  83   /* Allocate storage for the destination.  */
  84   destptr = (GFC_COMPLEX_4 *)internal_malloc_size (ssize * sizeof (GFC_COMPLEX_4));
  85   dest = destptr;
  86   src = source->data;
  87   stride0 = stride[0];
  88
  89
  90   while (src)
  91     {
  92       /* Copy the data.  */
  93       *(dest++) = *src;
  94       /* Advance to the next element.  */
  95       src += stride0;
  96       count[0]++;
  97       /* Advance to the next source element.  */
  98       n = 0;
  99       while (count[n] == extent[n])
 100         {
 101           /* When we get to the end of a dimension, reset it and increment
 102              the next dimension.  */
 103           count[n] = 0;
 104           /* We could precalculate these products, but this is a less
 105              frequently used path so probably not worth it.  */
 106           src -= stride[n] * extent[n];
 107           n++;
 108           if (n == dim)
 109             {
 110               src = NULL;
 111               break;
 112             }
 113           else
 114             {
 115               count[n]++;
 116               src += stride[n];
 117             }
 118         }
 119     }
 120   return destptr;
 121 }
 122
 123 #endif
 124