1  /* Helper function for repacking arrays.
       2     Copyright (C) 2003-2023 Free Software Foundation, Inc.
       3     Contributed by Paul Brook <paul@nowt.org>
       4  
       5  This file is part of the GNU Fortran 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 3 of the License, or (at your option) any later version.
      11  
      12  Libgfortran 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 General Public License for more details.
      16  
      17  Under Section 7 of GPL version 3, you are granted additional
      18  permissions described in the GCC Runtime Library Exception, version
      19  3.1, as published by the Free Software Foundation.
      20  
      21  You should have received a copy of the GNU General Public License and
      22  a copy of the GCC Runtime Library Exception along with this program;
      23  see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
      24  <http://www.gnu.org/licenses/>.  */
      25  
      26  #include "libgfortran.h"
      27  
      28  
      29  #if defined (HAVE_GFC_INTEGER_1)
      30  
      31  /* Allocates a block of memory with internal_malloc if the array needs
      32     repacking.  */
      33  
      34  GFC_INTEGER_1 *
      35  internal_pack_1 (gfc_array_i1 * source)
      36  {
      37    index_type count[GFC_MAX_DIMENSIONS];
      38    index_type extent[GFC_MAX_DIMENSIONS];
      39    index_type stride[GFC_MAX_DIMENSIONS];
      40    index_type stride0;
      41    index_type dim;
      42    index_type ssize;
      43    const GFC_INTEGER_1 *src;
      44    GFC_INTEGER_1 * restrict dest;
      45    GFC_INTEGER_1 *destptr;
      46    int packed;
      47  
      48    /* TODO: Investigate how we can figure out if this is a temporary
      49       since the stride=0 thing has been removed from the frontend.  */
      50  
      51    dim = GFC_DESCRIPTOR_RANK (source);
      52    ssize = 1;
      53    packed = 1;
      54    for (index_type n = 0; n < dim; n++)
      55      {
      56        count[n] = 0;
      57        stride[n] = GFC_DESCRIPTOR_STRIDE(source,n);
      58        extent[n] = GFC_DESCRIPTOR_EXTENT(source,n);
      59        if (extent[n] <= 0)
      60          {
      61            /* Do nothing.  */
      62            packed = 1;
      63            break;
      64          }
      65  
      66        if (ssize != stride[n])
      67          packed = 0;
      68  
      69        ssize *= extent[n];
      70      }
      71  
      72    if (packed)
      73      return source->base_addr;
      74  
      75    /* Allocate storage for the destination.  */
      76    destptr = xmallocarray (ssize, sizeof (GFC_INTEGER_1));
      77    dest = destptr;
      78    src = source->base_addr;
      79    stride0 = stride[0];
      80  
      81  
      82    while (src)
      83      {
      84        /* Copy the data.  */
      85        *(dest++) = *src;
      86        /* Advance to the next element.  */
      87        src += stride0;
      88        count[0]++;
      89        /* Advance to the next source element.  */
      90        index_type n = 0;
      91        while (count[n] == extent[n])
      92          {
      93            /* When we get to the end of a dimension, reset it and increment
      94               the next dimension.  */
      95            count[n] = 0;
      96            /* We could precalculate these products, but this is a less
      97               frequently used path so probably not worth it.  */
      98            src -= stride[n] * extent[n];
      99            n++;
     100            if (n == dim)
     101              {
     102                src = NULL;
     103                break;
     104              }
     105            else
     106              {
     107                count[n]++;
     108                src += stride[n];
     109              }
     110          }
     111      }
     112    return destptr;
     113  }
     114  
     115  #endif
     116