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`/* Implementation of the CSHIFT intrinsic.
Copyright (C) 2017-2021 Free Software Foundation, Inc.
Contributed by Thomas Koenig <tkoenig@gcc.gnu.org>
This file is part of the GNU Fortran 95 runtime library (libgfortran).
Libgfortran is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public
License as published by the Free Software Foundation; either
version 3 of the License, or (at your option) any later version.
Libgfortran 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 General Public License for more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
#include "libgfortran.h"
#include <string.h>'
include(iparm.m4)dnl
`#if defined (HAVE_'atype_name`) && defined (HAVE_'rtype_name`)
void
cshift1'rtype_qual`_'atype_code` ('atype` * const restrict ret,
const 'atype` * const restrict array,
const 'rtype` * const restrict h,
const 'rtype_name` * const restrict pwhich)
{
/* r.* indicates the return array. */
index_type rstride[GFC_MAX_DIMENSIONS];
index_type rstride0;
index_type roffset;
'atype_name` *rptr;
'atype_name` *dest;
/* s.* indicates the source array. */
index_type sstride[GFC_MAX_DIMENSIONS];
index_type sstride0;
index_type soffset;
const 'atype_name` *sptr;
const 'atype_name` *src;
/* h.* indicates the shift array. */
index_type hstride[GFC_MAX_DIMENSIONS];
index_type hstride0;
const 'rtype_name` *hptr;
index_type count[GFC_MAX_DIMENSIONS];
index_type extent[GFC_MAX_DIMENSIONS];
index_type rs_ex[GFC_MAX_DIMENSIONS];
index_type ss_ex[GFC_MAX_DIMENSIONS];
index_type hs_ex[GFC_MAX_DIMENSIONS];
index_type dim;
index_type len;
index_type n;
int which;
'rtype_name` sh;
/* Bounds checking etc is already done by the caller. */
if (pwhich)
which = *pwhich - 1;
else
which = 0;
extent[0] = 1;
count[0] = 0;
n = 0;
/* Initialized for avoiding compiler warnings. */
roffset = 1;
soffset = 1;
len = 0;
for (dim = 0; dim < GFC_DESCRIPTOR_RANK (array); dim++)
{
if (dim == which)
{
roffset = GFC_DESCRIPTOR_STRIDE(ret,dim);
if (roffset == 0)
roffset = 1;
soffset = GFC_DESCRIPTOR_STRIDE(array,dim);
if (soffset == 0)
soffset = 1;
len = GFC_DESCRIPTOR_EXTENT(array,dim);
}
else
{
count[n] = 0;
extent[n] = GFC_DESCRIPTOR_EXTENT(array,dim);
rstride[n] = GFC_DESCRIPTOR_STRIDE(ret,dim);
sstride[n] = GFC_DESCRIPTOR_STRIDE(array,dim);
hstride[n] = GFC_DESCRIPTOR_STRIDE(h,n);
rs_ex[n] = rstride[n] * extent[n];
ss_ex[n] = sstride[n] * extent[n];
hs_ex[n] = hstride[n] * extent[n];
n++;
}
}
if (sstride[0] == 0)
sstride[0] = 1;
if (rstride[0] == 0)
rstride[0] = 1;
if (hstride[0] == 0)
hstride[0] = 1;
dim = GFC_DESCRIPTOR_RANK (array);
rstride0 = rstride[0];
sstride0 = sstride[0];
hstride0 = hstride[0];
rptr = ret->base_addr;
sptr = array->base_addr;
hptr = h->base_addr;
while (rptr)
{
/* Do the shift for this dimension. */
sh = *hptr;
/* Normal case should be -len < sh < len; try to
avoid the expensive remainder operation if possible. */
if (sh < 0)
sh += len;
if (unlikely(sh >= len || sh < 0))
{
sh = sh % len;
if (sh < 0)
sh += len;
}
src = &sptr[sh * soffset];
dest = rptr;
if (soffset == 1 && roffset == 1)
{
size_t len1 = sh * sizeof ('atype_name`);
size_t len2 = (len - sh) * sizeof ('atype_name`);
memcpy (rptr, sptr + sh, len2);
memcpy (rptr + (len - sh), sptr, len1);
}
else
{
for (n = 0; n < len - sh; n++)
{
*dest = *src;
dest += roffset;
src += soffset;
}
for (src = sptr, n = 0; n < sh; n++)
{
*dest = *src;
dest += roffset;
src += soffset;
}
}
/* Advance to the next section. */
rptr += rstride0;
sptr += sstride0;
hptr += hstride0;
count[0]++;
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;
rptr -= rs_ex[n];
sptr -= ss_ex[n];
hptr -= hs_ex[n];
n++;
if (n >= dim - 1)
{
/* Break out of the loop. */
rptr = NULL;
break;
}
else
{
count[n]++;
rptr += rstride[n];
sptr += sstride[n];
hptr += hstride[n];
}
}
}
}
#endif'