libgfortran/generated/pack_c4.c

   1 /* Specific implementation of the PACK intrinsic
   2    Copyright (C) 2002-2021 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 Ligbfortran 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 #include <string.h>
  28
  29
  30 #if defined (HAVE_GFC_COMPLEX_4)
  31
  32 /* PACK is specified as follows:
  33
  34    13.14.80 PACK (ARRAY, MASK, [VECTOR])
  35
  36    Description: Pack an array into an array of rank one under the
  37    control of a mask.
  38
  39    Class: Transformational function.
  40
  41    Arguments:
  42       ARRAY   may be of any type. It shall not be scalar.
  43       MASK    shall be of type LOGICAL. It shall be conformable with ARRAY.
  44       VECTOR  (optional) shall be of the same type and type parameters
  45               as ARRAY. VECTOR shall have at least as many elements as
  46               there are true elements in MASK. If MASK is a scalar
  47               with the value true, VECTOR shall have at least as many
  48               elements as there are in ARRAY.
  49
  50    Result Characteristics: The result is an array of rank one with the
  51    same type and type parameters as ARRAY. If VECTOR is present, the
  52    result size is that of VECTOR; otherwise, the result size is the
  53    number /t/ of true elements in MASK unless MASK is scalar with the
  54    value true, in which case the result size is the size of ARRAY.
  55
  56    Result Value: Element /i/ of the result is the element of ARRAY
  57    that corresponds to the /i/th true element of MASK, taking elements
  58    in array element order, for /i/ = 1, 2, ..., /t/. If VECTOR is
  59    present and has size /n/ > /t/, element /i/ of the result has the
  60    value VECTOR(/i/), for /i/ = /t/ + 1, ..., /n/.
  61
  62    Examples: The nonzero elements of an array M with the value
  63    | 0 0 0 |
  64    | 9 0 0 | may be "gathered" by the function PACK. The result of
  65    | 0 0 7 |
  66    PACK (M, MASK = M.NE.0) is [9,7] and the result of PACK (M, M.NE.0,
  67    VECTOR = (/ 2,4,6,8,10,12 /)) is [9,7,6,8,10,12].
  68
  69 There are two variants of the PACK intrinsic: one, where MASK is
  70 array valued, and the other one where MASK is scalar.  */
  71
  72 void
  73 pack_c4 (gfc_array_c4 *ret, const gfc_array_c4 *array,
  74                const gfc_array_l1 *mask, const gfc_array_c4 *vector)
  75 {
  76   /* r.* indicates the return array.  */
  77   index_type rstride0;
  78   GFC_COMPLEX_4 * restrict rptr;
  79   /* s.* indicates the source array.  */
  80   index_type sstride[GFC_MAX_DIMENSIONS];
  81   index_type sstride0;
  82   const GFC_COMPLEX_4 *sptr;
  83   /* m.* indicates the mask array.  */
  84   index_type mstride[GFC_MAX_DIMENSIONS];
  85   index_type mstride0;
  86   const GFC_LOGICAL_1 *mptr;
  87
  88   index_type count[GFC_MAX_DIMENSIONS];
  89   index_type extent[GFC_MAX_DIMENSIONS];
  90   int zero_sized;
  91   index_type n;
  92   index_type dim;
  93   index_type nelem;
  94   index_type total;
  95   int mask_kind;
  96
  97   dim = GFC_DESCRIPTOR_RANK (array);
  98
  99   mptr = mask->base_addr;
 100
 101   /* Use the same loop for all logical types, by using GFC_LOGICAL_1
 102      and using shifting to address size and endian issues.  */
 103
 104   mask_kind = GFC_DESCRIPTOR_SIZE (mask);
 105
 106   if (mask_kind == 1 || mask_kind == 2 || mask_kind == 4 || mask_kind == 8
 107 #ifdef HAVE_GFC_LOGICAL_16
 108       || mask_kind == 16
 109 #endif
 110       )
 111     {
 112       /*  Do not convert a NULL pointer as we use test for NULL below.  */
 113       if (mptr)
 114         mptr = GFOR_POINTER_TO_L1 (mptr, mask_kind);
 115     }
 116   else
 117     runtime_error ("Funny sized logical array");
 118
 119   zero_sized = 0;
 120   for (n = 0; n < dim; n++)
 121     {
 122       count[n] = 0;
 123       extent[n] = GFC_DESCRIPTOR_EXTENT(array,n);
 124       if (extent[n] <= 0)
 125        zero_sized = 1;
 126       sstride[n] = GFC_DESCRIPTOR_STRIDE(array,n);
 127       mstride[n] = GFC_DESCRIPTOR_STRIDE_BYTES(mask,n);
 128     }
 129   if (sstride[0] == 0)
 130     sstride[0] = 1;
 131   if (mstride[0] == 0)
 132     mstride[0] = mask_kind;
 133
 134   if (zero_sized)
 135     sptr = NULL;
 136   else
 137     sptr = array->base_addr;
 138
 139   if (ret->base_addr == NULL || unlikely (compile_options.bounds_check))
 140     {
 141       /* Count the elements, either for allocating memory or
 142          for bounds checking.  */
 143
 144       if (vector != NULL)
 145         {
 146           /* The return array will have as many
 147              elements as there are in VECTOR.  */
 148           total = GFC_DESCRIPTOR_EXTENT(vector,0);
 149           if (total < 0)
 150             {
 151               total = 0;
 152               vector = NULL;
 153             }
 154         }
 155       else
 156         {
 157           /* We have to count the true elements in MASK.  */
 158           total = count_0 (mask);
 159         }
 160
 161       if (ret->base_addr == NULL)
 162         {
 163           /* Setup the array descriptor.  */
 164           GFC_DIMENSION_SET(ret->dim[0], 0, total-1, 1);
 165
 166           ret->offset = 0;
 167
 168           /* xmallocarray allocates a single byte for zero size.  */
 169           ret->base_addr = xmallocarray (total, sizeof (GFC_COMPLEX_4));
 170
 171           if (total == 0)
 172             return;
 173         }
 174       else
 175         {
 176           /* We come here because of range checking.  */
 177           index_type ret_extent;
 178
 179           ret_extent = GFC_DESCRIPTOR_EXTENT(ret,0);
 180           if (total != ret_extent)
 181             runtime_error ("Incorrect extent in return value of PACK intrinsic;"
 182                            " is %ld, should be %ld", (long int) total,
 183                            (long int) ret_extent);
 184         }
 185     }
 186
 187   rstride0 = GFC_DESCRIPTOR_STRIDE(ret,0);
 188   if (rstride0 == 0)
 189     rstride0 = 1;
 190   sstride0 = sstride[0];
 191   mstride0 = mstride[0];
 192   rptr = ret->base_addr;
 193
 194   while (sptr && mptr)
 195     {
 196       /* Test this element.  */
 197       if (*mptr)
 198         {
 199           /* Add it.  */
 200           *rptr = *sptr;
 201           rptr += rstride0;
 202         }
 203       /* Advance to the next element.  */
 204       sptr += sstride0;
 205       mptr += mstride0;
 206       count[0]++;
 207       n = 0;
 208       while (count[n] == extent[n])
 209         {
 210           /* When we get to the end of a dimension, reset it and increment
 211              the next dimension.  */
 212           count[n] = 0;
 213           /* We could precalculate these products, but this is a less
 214              frequently used path so probably not worth it.  */
 215           sptr -= sstride[n] * extent[n];
 216           mptr -= mstride[n] * extent[n];
 217           n++;
 218           if (n >= dim)
 219             {
 220               /* Break out of the loop.  */
 221               sptr = NULL;
 222               break;
 223             }
 224           else
 225             {
 226               count[n]++;
 227               sptr += sstride[n];
 228               mptr += mstride[n];
 229             }
 230         }
 231     }
 232
 233   /* Add any remaining elements from VECTOR.  */
 234   if (vector)
 235     {
 236       n = GFC_DESCRIPTOR_EXTENT(vector,0);
 237       nelem = ((rptr - ret->base_addr) / rstride0);
 238       if (n > nelem)
 239         {
 240           sstride0 = GFC_DESCRIPTOR_STRIDE(vector,0);
 241           if (sstride0 == 0)
 242             sstride0 = 1;
 243
 244           sptr = vector->base_addr + sstride0 * nelem;
 245           n -= nelem;
 246           while (n--)
 247             {
 248               *rptr = *sptr;
 249               rptr += rstride0;
 250               sptr += sstride0;
 251             }
 252         }
 253     }
 254 }
 255
 256 #endif
 257