1 /* Implementation of the NORM2 intrinsic
2 Copyright (C) 2010-2023 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 #if defined(GFC_REAL_16_USE_IEC_60559)
34 #define MATHFUNC(funcname) funcname ## f128
35 #else
36 #define MATHFUNC(funcname) funcname ## q
37 #endif
38 #else
39 #define MATHFUNC(funcname) funcname ## l
40 #endif
41
42
43 extern void norm2_r16 (gfc_array_r16 * const restrict,
44 gfc_array_r16 * const restrict, const index_type * const restrict);
45 export_proto(norm2_r16);
46
47 void
48 norm2_r16 (gfc_array_r16 * const restrict retarray,
49 gfc_array_r16 * const restrict array,
50 const index_type * const restrict pdim)
51 {
52 index_type count[GFC_MAX_DIMENSIONS];
53 index_type extent[GFC_MAX_DIMENSIONS];
54 index_type sstride[GFC_MAX_DIMENSIONS];
55 index_type dstride[GFC_MAX_DIMENSIONS];
56 const GFC_REAL_16 * restrict base;
57 GFC_REAL_16 * restrict dest;
58 index_type rank;
59 index_type n;
60 index_type len;
61 index_type delta;
62 index_type dim;
63 int continue_loop;
64
65 /* Make dim zero based to avoid confusion. */
66 rank = GFC_DESCRIPTOR_RANK (array) - 1;
67 dim = (*pdim) - 1;
68
69 if (unlikely (dim < 0 || dim > rank))
70 {
71 runtime_error ("Dim argument incorrect in NORM intrinsic: "
72 "is %ld, should be between 1 and %ld",
73 (long int) dim + 1, (long int) rank + 1);
74 }
75
76 len = GFC_DESCRIPTOR_EXTENT(array,dim);
77 if (len < 0)
78 len = 0;
79 delta = GFC_DESCRIPTOR_STRIDE(array,dim);
80
81 for (n = 0; n < dim; n++)
82 {
83 sstride[n] = GFC_DESCRIPTOR_STRIDE(array,n);
84 extent[n] = GFC_DESCRIPTOR_EXTENT(array,n);
85
86 if (extent[n] < 0)
87 extent[n] = 0;
88 }
89 for (n = dim; n < rank; n++)
90 {
91 sstride[n] = GFC_DESCRIPTOR_STRIDE(array, n + 1);
92 extent[n] = GFC_DESCRIPTOR_EXTENT(array, n + 1);
93
94 if (extent[n] < 0)
95 extent[n] = 0;
96 }
97
98 if (retarray->base_addr == NULL)
99 {
100 size_t alloc_size, str;
101
102 for (n = 0; n < rank; n++)
103 {
104 if (n == 0)
105 str = 1;
106 else
107 str = GFC_DESCRIPTOR_STRIDE(retarray,n-1) * extent[n-1];
108
109 GFC_DIMENSION_SET(retarray->dim[n], 0, extent[n] - 1, str);
110
111 }
112
113 retarray->offset = 0;
114 retarray->dtype.rank = rank;
115
116 alloc_size = GFC_DESCRIPTOR_STRIDE(retarray,rank-1) * extent[rank-1];
117
118 retarray->base_addr = xmallocarray (alloc_size, sizeof (GFC_REAL_16));
119 if (alloc_size == 0)
120 {
121 /* Make sure we have a zero-sized array. */
122 GFC_DIMENSION_SET(retarray->dim[0], 0, -1, 1);
123 return;
124
125 }
126 }
127 else
128 {
129 if (rank != GFC_DESCRIPTOR_RANK (retarray))
130 runtime_error ("rank of return array incorrect in"
131 " NORM intrinsic: is %ld, should be %ld",
132 (long int) (GFC_DESCRIPTOR_RANK (retarray)),
133 (long int) rank);
134
135 if (unlikely (compile_options.bounds_check))
136 bounds_ifunction_return ((array_t *) retarray, extent,
137 "return value", "NORM");
138 }
139
140 for (n = 0; n < rank; n++)
141 {
142 count[n] = 0;
143 dstride[n] = GFC_DESCRIPTOR_STRIDE(retarray,n);
144 if (extent[n] <= 0)
145 return;
146 }
147
148 base = array->base_addr;
149 dest = retarray->base_addr;
150
151 continue_loop = 1;
152 while (continue_loop)
153 {
154 const GFC_REAL_16 * restrict src;
155 GFC_REAL_16 result;
156 src = base;
157 {
158
159 GFC_REAL_16 scale;
160 result = 0;
161 scale = 1;
162 if (len <= 0)
163 *dest = 0;
164 else
165 {
166 #if ! defined HAVE_BACK_ARG
167 for (n = 0; n < len; n++, src += delta)
168 {
169 #endif
170
171 if (*src != 0)
172 {
173 GFC_REAL_16 absX, val;
174 absX = MATHFUNC(fabs) (*src);
175 if (scale < absX)
176 {
177 val = scale / absX;
178 result = 1 + result * val * val;
179 scale = absX;
180 }
181 else
182 {
183 val = absX / scale;
184 result += val * val;
185 }
186 }
187 }
188 result = scale * MATHFUNC(sqrt) (result);
189 *dest = result;
190 }
191 }
192 /* Advance to the next element. */
193 count[0]++;
194 base += sstride[0];
195 dest += dstride[0];
196 n = 0;
197 while (count[n] == extent[n])
198 {
199 /* When we get to the end of a dimension, reset it and increment
200 the next dimension. */
201 count[n] = 0;
202 /* We could precalculate these products, but this is a less
203 frequently used path so probably not worth it. */
204 base -= sstride[n] * extent[n];
205 dest -= dstride[n] * extent[n];
206 n++;
207 if (n >= rank)
208 {
209 /* Break out of the loop. */
210 continue_loop = 0;
211 break;
212 }
213 else
214 {
215 count[n]++;
216 base += sstride[n];
217 dest += dstride[n];
218 }
219 }
220 }
221 }
222
223 #endif