gcc/libgfortran/m4/in_pack.m4

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`/* Helper function for repacking arrays.
Copyright 2003 Free Software Foundation, Inc.
Contributed by Paul Brook <paul@nowt.org>
This file is part of the GNU Fortran 95 runtime library (libgfortran).
Libgfor is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
Ligbfor is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with libgfortran; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include "config.h"
#include <stdlib.h>
#include <assert.h>
#include "libgfortran.h"'
include(iparm.m4)dnl
/* Allocates a block of memory with internal_malloc if the array needs
repacking. */
dnl Only the kind (ie size) is used to name the function.
rtype_name *
`internal_pack_'rtype_kind (rtype * source)
{
index_type count[GFC_MAX_DIMENSIONS - 1];
index_type extent[GFC_MAX_DIMENSIONS - 1];
index_type stride[GFC_MAX_DIMENSIONS - 1];
index_type stride0;
index_type dim;
index_type ssize;
const rtype_name *src;
rtype_name *dest;
rtype_name *destptr;
int n;
int packed;
if (source->dim[0].stride == 0)
{
source->dim[0].stride = 1;
return source->data;
}
dim = GFC_DESCRIPTOR_RANK (source);
ssize = 1;
packed = 1;
for (n = 0; n < dim; n++)
{
count[n] = 0;
stride[n] = source->dim[n].stride;
extent[n] = source->dim[n].ubound + 1 - source->dim[n].lbound;
if (extent[n] <= 0)
{
/* Do nothing. */
packed = 1;
break;
}
if (ssize != stride[n])
packed = 0;
ssize *= extent[n];
}
if (packed)
return source->data;
/* Allocate storage for the destination. */
destptr = (rtype_name *)internal_malloc_size (ssize * rtype_kind);
dest = destptr;
src = source->data;
stride0 = stride[0];
while (src)
{
/* Copy the data. */
*(dest++) = *src;
/* Advance to the next element. */
src += stride0;
count[0]++;
/* Advance to the next source element. */
n = 0;
while (count[n] == extent[n])
{
/* When we get to the end of a dimension, reset it and increment
the next dimension. */
count[n] = 0;
/* We could precalculate these products, but this is a less
frequently used path so proabably not worth it. */
src -= stride[n] * extent[n];
n++;
if (n == dim)
{
src = NULL;
break;
}
else
{
count[n]++;
src += stride[n];
}
}
}
return destptr;
}