libgfortran/generated/norm2_r16.c

   1 /* Implementation of the NORM2 intrinsic
   2    Copyright 2010 Free Software Foundation, Inc.
   3    Contributed by Tobias Burnus  <burnus@net-b.de>
   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 #include <stdlib.h>
  28 #include <math.h>
  29 #include <assert.h>
  30
  31
  32
  33 #if defined (HAVE_GFC_REAL_16) && defined (HAVE_GFC_REAL_16) && (defined(GFC_REAL_16_IS_FLOAT128) || defined(HAVE_SQRTL)) && (defined(GFC_REAL_16_IS_FLOAT128) || defined(HAVE_FABSL))
  34
  35 #if defined(GFC_REAL_16_IS_FLOAT128)
  36 #define MATHFUNC(funcname) funcname ## q
  37 #else
  38 #define MATHFUNC(funcname) funcname ## l
  39 #endif
  40 #if defined(GFC_REAL_16_IS_FLOAT128)
  41 #define BUILTINMATHFUNC(funcname) funcname ## q
  42 #else
  43 #define BUILTINMATHFUNC(funcname) funcname ## l
  44 #endif
  45
  46
  47 extern void norm2_r16 (gfc_array_r16 * const restrict,
  48         gfc_array_r16 * const restrict, const index_type * const restrict);
  49 export_proto(norm2_r16);
  50
  51 void
  52 norm2_r16 (gfc_array_r16 * const restrict retarray,
  53         gfc_array_r16 * const restrict array,
  54         const index_type * const restrict pdim)
  55 {
  56   index_type count[GFC_MAX_DIMENSIONS];
  57   index_type extent[GFC_MAX_DIMENSIONS];
  58   index_type sstride[GFC_MAX_DIMENSIONS];
  59   index_type dstride[GFC_MAX_DIMENSIONS];
  60   const GFC_REAL_16 * restrict base;
  61   GFC_REAL_16 * restrict dest;
  62   index_type rank;
  63   index_type n;
  64   index_type len;
  65   index_type delta;
  66   index_type dim;
  67   int continue_loop;
  68
  69   /* Make dim zero based to avoid confusion.  */
  70   dim = (*pdim) - 1;
  71   rank = GFC_DESCRIPTOR_RANK (array) - 1;
  72
  73   len = GFC_DESCRIPTOR_EXTENT(array,dim);
  74   if (len < 0)
  75     len = 0;
  76   delta = GFC_DESCRIPTOR_STRIDE(array,dim);
  77
  78   for (n = 0; n < dim; n++)
  79     {
  80       sstride[n] = GFC_DESCRIPTOR_STRIDE(array,n);
  81       extent[n] = GFC_DESCRIPTOR_EXTENT(array,n);
  82
  83       if (extent[n] < 0)
  84         extent[n] = 0;
  85     }
  86   for (n = dim; n < rank; n++)
  87     {
  88       sstride[n] = GFC_DESCRIPTOR_STRIDE(array, n + 1);
  89       extent[n] = GFC_DESCRIPTOR_EXTENT(array, n + 1);
  90
  91       if (extent[n] < 0)
  92         extent[n] = 0;
  93     }
  94
  95   if (retarray->data == NULL)
  96     {
  97       size_t alloc_size, str;
  98
  99       for (n = 0; n < rank; n++)
 100         {
 101           if (n == 0)
 102             str = 1;
 103           else
 104             str = GFC_DESCRIPTOR_STRIDE(retarray,n-1) * extent[n-1];
 105
 106           GFC_DIMENSION_SET(retarray->dim[n], 0, extent[n] - 1, str);
 107
 108         }
 109
 110       retarray->offset = 0;
 111       retarray->dtype = (array->dtype & ~GFC_DTYPE_RANK_MASK) | rank;
 112
 113       alloc_size = sizeof (GFC_REAL_16) * GFC_DESCRIPTOR_STRIDE(retarray,rank-1)
 114                    * extent[rank-1];
 115
 116       if (alloc_size == 0)
 117         {
 118           /* Make sure we have a zero-sized array.  */
 119           GFC_DIMENSION_SET(retarray->dim[0], 0, -1, 1);
 120           return;
 121
 122         }
 123       else
 124         retarray->data = internal_malloc_size (alloc_size);
 125     }
 126   else
 127     {
 128       if (rank != GFC_DESCRIPTOR_RANK (retarray))
 129         runtime_error ("rank of return array incorrect in"
 130                        " NORM intrinsic: is %ld, should be %ld",
 131                        (long int) (GFC_DESCRIPTOR_RANK (retarray)),
 132                        (long int) rank);
 133
 134       if (unlikely (compile_options.bounds_check))
 135         bounds_ifunction_return ((array_t *) retarray, extent,
 136                                  "return value", "NORM");
 137     }
 138
 139   for (n = 0; n < rank; n++)
 140     {
 141       count[n] = 0;
 142       dstride[n] = GFC_DESCRIPTOR_STRIDE(retarray,n);
 143       if (extent[n] <= 0)
 144         len = 0;
 145     }
 146
 147   base = array->data;
 148   dest = retarray->data;
 149
 150   continue_loop = 1;
 151   while (continue_loop)
 152     {
 153       const GFC_REAL_16 * restrict src;
 154       GFC_REAL_16 result;
 155       src = base;
 156       {
 157
 158         GFC_REAL_16 scale;
 159         result = 0;
 160         scale = 1;
 161         if (len <= 0)
 162           *dest = 0;
 163         else
 164           {
 165             for (n = 0; n < len; n++, src += delta)
 166               {
 167
 168           if (*src != 0)
 169             {
 170               GFC_REAL_16 absX, val;
 171               absX = MATHFUNC(fabs) (*src);
 172               if (scale < absX)
 173                 {
 174                   val = scale / absX;
 175                   result = 1 + result * val * val;
 176                   scale = absX;
 177                 }
 178               else
 179                 {
 180                   val = absX / scale;
 181                   result += val * val;
 182                 }
 183             }
 184               }
 185             result = scale * MATHFUNC(sqrt) (result);
 186             *dest = result;
 187           }
 188       }
 189       /* Advance to the next element.  */
 190       count[0]++;
 191       base += sstride[0];
 192       dest += dstride[0];
 193       n = 0;
 194       while (count[n] == extent[n])
 195         {
 196           /* When we get to the end of a dimension, reset it and increment
 197              the next dimension.  */
 198           count[n] = 0;
 199           /* We could precalculate these products, but this is a less
 200              frequently used path so probably not worth it.  */
 201           base -= sstride[n] * extent[n];
 202           dest -= dstride[n] * extent[n];
 203           n++;
 204           if (n == rank)
 205             {
 206               /* Break out of the look.  */
 207               continue_loop = 0;
 208               break;
 209             }
 210           else
 211             {
 212               count[n]++;
 213               base += sstride[n];
 214               dest += dstride[n];
 215             }
 216         }
 217     }
 218 }
 219
 220 #endif