1 /* Implementation of the NORM2 intrinsic
2 Copyright (C) 2010-2022 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
28
29
30 #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))
31
32 #if defined(GFC_REAL_16_IS_FLOAT128)
33 #define MATHFUNC(funcname) funcname ## q
34 #else
35 #define MATHFUNC(funcname) funcname ## l
36 #endif
37
38
39 extern void norm2_r16 (gfc_array_r16 * const restrict,
40 gfc_array_r16 * const restrict, const index_type * const restrict);
41 export_proto(norm2_r16);
42
43 void
norm2_r16(gfc_array_r16 * const restrict retarray,gfc_array_r16 * const restrict array,const index_type * const restrict pdim)44 norm2_r16 (gfc_array_r16 * const restrict retarray,
45 gfc_array_r16 * const restrict array,
46 const index_type * const restrict pdim)
47 {
48 index_type count[GFC_MAX_DIMENSIONS];
49 index_type extent[GFC_MAX_DIMENSIONS];
50 index_type sstride[GFC_MAX_DIMENSIONS];
51 index_type dstride[GFC_MAX_DIMENSIONS];
52 const GFC_REAL_16 * restrict base;
53 GFC_REAL_16 * restrict dest;
54 index_type rank;
55 index_type n;
56 index_type len;
57 index_type delta;
58 index_type dim;
59 int continue_loop;
60
61 /* Make dim zero based to avoid confusion. */
62 rank = GFC_DESCRIPTOR_RANK (array) - 1;
63 dim = (*pdim) - 1;
64
65 if (unlikely (dim < 0 || dim > rank))
66 {
67 runtime_error ("Dim argument incorrect in NORM intrinsic: "
68 "is %ld, should be between 1 and %ld",
69 (long int) dim + 1, (long int) rank + 1);
70 }
71
72 len = GFC_DESCRIPTOR_EXTENT(array,dim);
73 if (len < 0)
74 len = 0;
75 delta = GFC_DESCRIPTOR_STRIDE(array,dim);
76
77 for (n = 0; n < dim; n++)
78 {
79 sstride[n] = GFC_DESCRIPTOR_STRIDE(array,n);
80 extent[n] = GFC_DESCRIPTOR_EXTENT(array,n);
81
82 if (extent[n] < 0)
83 extent[n] = 0;
84 }
85 for (n = dim; n < rank; n++)
86 {
87 sstride[n] = GFC_DESCRIPTOR_STRIDE(array, n + 1);
88 extent[n] = GFC_DESCRIPTOR_EXTENT(array, n + 1);
89
90 if (extent[n] < 0)
91 extent[n] = 0;
92 }
93
94 if (retarray->base_addr == NULL)
95 {
96 size_t alloc_size, str;
97
98 for (n = 0; n < rank; n++)
99 {
100 if (n == 0)
101 str = 1;
102 else
103 str = GFC_DESCRIPTOR_STRIDE(retarray,n-1) * extent[n-1];
104
105 GFC_DIMENSION_SET(retarray->dim[n], 0, extent[n] - 1, str);
106
107 }
108
109 retarray->offset = 0;
110 retarray->dtype.rank = rank;
111
112 alloc_size = GFC_DESCRIPTOR_STRIDE(retarray,rank-1) * extent[rank-1];
113
114 retarray->base_addr = xmallocarray (alloc_size, sizeof (GFC_REAL_16));
115 if (alloc_size == 0)
116 {
117 /* Make sure we have a zero-sized array. */
118 GFC_DIMENSION_SET(retarray->dim[0], 0, -1, 1);
119 return;
120
121 }
122 }
123 else
124 {
125 if (rank != GFC_DESCRIPTOR_RANK (retarray))
126 runtime_error ("rank of return array incorrect in"
127 " NORM intrinsic: is %ld, should be %ld",
128 (long int) (GFC_DESCRIPTOR_RANK (retarray)),
129 (long int) rank);
130
131 if (unlikely (compile_options.bounds_check))
132 bounds_ifunction_return ((array_t *) retarray, extent,
133 "return value", "NORM");
134 }
135
136 for (n = 0; n < rank; n++)
137 {
138 count[n] = 0;
139 dstride[n] = GFC_DESCRIPTOR_STRIDE(retarray,n);
140 if (extent[n] <= 0)
141 return;
142 }
143
144 base = array->base_addr;
145 dest = retarray->base_addr;
146
147 continue_loop = 1;
148 while (continue_loop)
149 {
150 const GFC_REAL_16 * restrict src;
151 GFC_REAL_16 result;
152 src = base;
153 {
154
155 GFC_REAL_16 scale;
156 result = 0;
157 scale = 1;
158 if (len <= 0)
159 *dest = 0;
160 else
161 {
162 #if ! defined HAVE_BACK_ARG
163 for (n = 0; n < len; n++, src += delta)
164 {
165 #endif
166
167 if (*src != 0)
168 {
169 GFC_REAL_16 absX, val;
170 absX = MATHFUNC(fabs) (*src);
171 if (scale < absX)
172 {
173 val = scale / absX;
174 result = 1 + result * val * val;
175 scale = absX;
176 }
177 else
178 {
179 val = absX / scale;
180 result += val * val;
181 }
182 }
183 }
184 result = scale * MATHFUNC(sqrt) (result);
185 *dest = result;
186 }
187 }
188 /* Advance to the next element. */
189 count[0]++;
190 base += sstride[0];
191 dest += dstride[0];
192 n = 0;
193 while (count[n] == extent[n])
194 {
195 /* When we get to the end of a dimension, reset it and increment
196 the next dimension. */
197 count[n] = 0;
198 /* We could precalculate these products, but this is a less
199 frequently used path so probably not worth it. */
200 base -= sstride[n] * extent[n];
201 dest -= dstride[n] * extent[n];
202 n++;
203 if (n >= rank)
204 {
205 /* Break out of the loop. */
206 continue_loop = 0;
207 break;
208 }
209 else
210 {
211 count[n]++;
212 base += sstride[n];
213 dest += dstride[n];
214 }
215 }
216 }
217 }
218
219 #endif
220