1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
|
/* Generate table of tests in tst-strtod-round.c from
tst-strtod-round-data.
Copyright (C) 2012-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
/* Compile this program as:
gcc -std=gnu11 -O2 -Wall -Wextra gen-tst-strtod-round.c -lmpfr \
-o gen-tst-strtod-round
(use of current MPFR version recommended) and run it as:
gen-tst-strtod-round tst-strtod-round-data tst-strtod-round-data.h
The output file will be generated as tst-strtod-round-data.h
*/
#define _GNU_SOURCE
#include <assert.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <mpfr.h>
/* Work around incorrect ternary value from mpfr_strtofr
<https://sympa.inria.fr/sympa/arc/mpfr/2012-08/msg00005.html>. */
#define WORKAROUND
static int
string_to_fp (mpfr_t f, const char *s, mpfr_rnd_t rnd)
{
mpfr_clear_overflow ();
mpfr_clear_underflow ();
#ifdef WORKAROUND
mpfr_t f2;
mpfr_init2 (f2, 100000);
int r0 = mpfr_strtofr (f2, s, NULL, 0, rnd);
int r = mpfr_set (f, f2, rnd);
r |= mpfr_subnormalize (f, r, rnd);
mpfr_clear (f2);
r |= r0;
#else
int r = mpfr_strtofr (f, s, NULL, 0, rnd);
r |= mpfr_subnormalize (f, r, rnd);
#endif
if (r == 0)
/* The MPFR underflow flag is set for exact subnormal results,
which is not wanted here. */
mpfr_clear_underflow ();
return r;
}
void
print_fp (FILE *fout, mpfr_t f, const char *suffix)
{
if (mpfr_inf_p (f))
mpfr_fprintf (fout, "\t%sINF%s", mpfr_signbit (f) ? "-" : "", suffix);
else
mpfr_fprintf (fout, "\t%Ra%s", f, suffix);
}
static const char *
suffix_to_print (bool overflow, bool underflow, bool underflow_before_rounding,
bool with_comma)
{
if (overflow)
return with_comma ? ", true, false,\n" : ", true, false";
if (underflow)
return with_comma ? ", false, true,\n" : ", false, true";
if (underflow_before_rounding)
return (with_comma
? ", false, !TININESS_AFTER_ROUNDING,\n"
: ", false, !TININESS_AFTER_ROUNDING");
return with_comma ? ", false, false,\n" : ", false, false";
}
static void
round_str (FILE *fout, const char *s, int prec, int emin, int emax,
bool ibm_ld)
{
mpfr_t max_value;
mpfr_t f;
mpfr_set_default_prec (prec);
mpfr_set_emin (emin);
mpfr_set_emax (emax);
mpfr_init (f);
string_to_fp (f, s, MPFR_RNDZ);
bool underflow_before_rounding = mpfr_underflow_p () != 0;
int r = string_to_fp (f, s, MPFR_RNDD);
bool overflow = mpfr_overflow_p () != 0;
bool underflow = mpfr_underflow_p () != 0;
if (ibm_ld)
{
assert (prec == 106 && emin == -1073 && emax == 1024);
/* The maximum value in IBM long double has discontiguous
mantissa bits. */
mpfr_init2 (max_value, 107);
mpfr_set_str (max_value, "0x1.fffffffffffff7ffffffffffffcp+1023", 0,
MPFR_RNDN);
if (mpfr_cmpabs (f, max_value) > 0)
{
r = 1;
overflow = true;
}
}
mpfr_fprintf (fout, "\t%s,\n", r ? "false" : "true");
print_fp (fout, f,
suffix_to_print (overflow, underflow, underflow_before_rounding,
true));
string_to_fp (f, s, MPFR_RNDN);
overflow = (mpfr_overflow_p () != 0
|| (ibm_ld && mpfr_cmpabs (f, max_value) > 0));
print_fp (fout, f,
suffix_to_print (overflow, underflow, underflow_before_rounding,
true));
string_to_fp (f, s, MPFR_RNDZ);
overflow = (mpfr_overflow_p () != 0
|| (ibm_ld && mpfr_cmpabs (f, max_value) > 0));
print_fp (fout, f,
suffix_to_print (overflow, underflow, underflow_before_rounding,
true));
string_to_fp (f, s, MPFR_RNDU);
overflow = (mpfr_overflow_p () != 0
|| (ibm_ld && mpfr_cmpabs (f, max_value) > 0));
print_fp (fout, f,
suffix_to_print (overflow, underflow, underflow_before_rounding,
false));
mpfr_clear (f);
if (ibm_ld)
mpfr_clear (max_value);
}
static void
round_for_all (FILE *fout, const char *s)
{
static const struct fmt {
int prec;
int emin;
int emax;
bool ibm_ld;
} formats[] = {
{ 24, -148, 128, false },
{ 53, -1073, 1024, false },
/* This is the Intel extended float format. */
{ 64, -16444, 16384, false },
/* This is the Motorola extended float format. */
{ 64, -16445, 16384, false },
{ 106, -1073, 1024, true },
{ 113, -16493, 16384, false },
};
mpfr_fprintf (fout, " TEST (\"");
const char *p;
for (p = s; *p; p++)
{
fputc (*p, fout);
if ((p - s) % 60 == 59 && p[1])
mpfr_fprintf (fout, "\"\n\t\"");
}
mpfr_fprintf (fout, "\",\n");
int i;
int n_formats = sizeof (formats) / sizeof (formats[0]);
for (i = 0; i < n_formats; i++)
{
round_str (fout, s, formats[i].prec, formats[i].emin,
formats[i].emax, formats[i].ibm_ld);
if (i < n_formats - 1)
mpfr_fprintf (fout, ",\n");
}
mpfr_fprintf (fout, "),\n");
}
int
main (int argc, char **argv)
{
char *p = NULL;
size_t len;
ssize_t nbytes;
FILE *fin, *fout;
char *fin_name, *fout_name;
if (argc < 3)
{
fprintf (stderr, "Usage: %s <input> <output>\n", basename (argv[0]));
return EXIT_FAILURE;
}
fin_name = argv[1];
fout_name = argv[2];
fin = fopen (fin_name, "r");
if (fin == NULL)
{
perror ("Could not open input for reading");
return EXIT_FAILURE;
}
fout = fopen (fout_name, "w");
if (fout == NULL)
{
perror ("Could not open output for writing");
return EXIT_FAILURE;
}
fprintf (fout, "/* This file was generated by %s from %s. */\n",
__FILE__, fin_name);
fputs ("static const struct test tests[] = {\n", fout);
while ((nbytes = getline (&p, &len, fin)) != -1)
{
if (p[nbytes - 1] == '\n')
p[nbytes - 1] = 0;
round_for_all (fout, p);
free (p);
p = NULL;
}
fputs ("};\n", fout);
return EXIT_SUCCESS;
}
|
