1 /* Test file for l2b constants.
2
3 Copyright 2007-2023 Free Software Foundation, Inc.
4 Contributed by the AriC and Caramba projects, INRIA.
5
6 This file is part of the GNU MPFR Library.
7
8 The GNU MPFR Library is free software; you can redistribute it and/or modify
9 it under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or (at your
11 option) any later version.
12
13 The GNU MPFR Library is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
16 License for more details.
17
18 You should have received a copy of the GNU Lesser General Public License
19 along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
20 https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
21 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
22
23 /* Execute this program with an argument to generate code that initializes
24 the l2b constants. */
25
26 #include "mpfr-test.h"
27
28 /* Must be a multiple of 4 */
29 static const int bits2use[] = {8, 16, 32, 64, 96, 128, 256};
30 #define size_of_bits2use (numberof (bits2use))
31
32 static __mpfr_struct l2b[BASE_MAX-1][2];
33
34 static void
35 print_mpfr (mpfr_srcptr x, const char *name)
36 {
37 unsigned char temp[16]; /* buffer for the base-256 string */
38 unsigned char *ptr; /* pointer to its first non-zero byte */
39 int size; /* size of the string */
40 int i; /* bits2use index */
41 int j; /* output limb index */
42 int k; /* byte index (in output limb) */
43 int r; /* digit index, relative to ptr */
44 char prefix[12]; /* "0x" or "UINT64_C(0x" */
45 char suffix[2]; /* "" or ")" */
46
47 if (printf ("#if 0\n") < 0)
48 { fprintf (stderr, "Error in printf\n"); exit (1); }
49 for (i = 0; i < size_of_bits2use; i++)
50 {
51 if (bits2use[i] == 64)
52 {
53 strcpy (prefix, "UINT64_C(0x");
54 strcpy (suffix, ")");
55 }
56 else
57 {
58 strcpy (prefix, "0x");
59 strcpy (suffix, "");
60 }
61 if (printf ("#elif GMP_NUMB_BITS == %d\n"
62 "const mp_limb_t %s__tab[] = { %s", bits2use[i], name,
63 prefix) < 0)
64 { fprintf (stderr, "Error in printf\n"); exit (1); }
65 size = mpn_get_str (temp, 256, MPFR_MANT (x), MPFR_LIMB_SIZE (x));
66 MPFR_ASSERTN (size <= 16);
67 ptr = temp;
68 /* Skip leading zeros. */
69 while (*ptr == 0)
70 {
71 ptr++;
72 size--;
73 MPFR_ASSERTN (size > 0);
74 }
75 MPFR_ASSERTN (*ptr >= 128);
76 for (j = (MPFR_PREC (x) - 1) / bits2use[i]; j >= 0; j--)
77 {
78 r = j * (bits2use[i] / 8);
79 for (k = 0; k < bits2use[i] / 8; k++)
80 if (printf ("%02x", r < size ? ptr[r++] : 0) < 0)
81 { fprintf (stderr, "Error in printf\n"); exit (1); }
82 if (j == 0 && printf ("%s };\n", suffix) < 0)
83 { fprintf (stderr, "Error in printf\n"); exit (1); }
84 else if (j > 0 && printf ("%s, %s", suffix, prefix) < 0)
85 { fprintf (stderr, "Error in printf\n"); exit (1); }
86 }
87 }
88 if (printf ("#endif\n\n") < 0)
89 { fprintf (stderr, "Error in printf\n"); exit (1); }
90 }
91
92 static void
93 compute_l2b (int output)
94 {
95 mpfr_ptr p;
96 mpfr_srcptr t;
97 int beta, i;
98 int error = 0;
99 char buffer[256]; /* larger than needed, for maintainability */
100
101 if (output)
102 printf ("#ifndef UINT64_C\n# define UINT64_C(c) c\n#endif\n\n");
103
104 for (beta = 2; beta <= BASE_MAX; beta++)
105 {
106 for (i = 0; i < 2; i++)
107 {
108 p = &l2b[beta-2][i];
109
110 /* Compute the value */
111 if (i == 0)
112 {
113 /* 23-bit upper approximation to log(b)/log(2) */
114 mpfr_init2 (p, 23);
115 mpfr_set_ui (p, beta, MPFR_RNDU);
116 mpfr_log2 (p, p, MPFR_RNDU);
117 }
118 else
119 {
120 /* 77-bit upper approximation to log(2)/log(b) */
121 mpfr_init2 (p, 77);
122 mpfr_set_ui (p, beta, MPFR_RNDD);
123 mpfr_log2 (p, p, MPFR_RNDD);
124 mpfr_ui_div (p, 1, p, MPFR_RNDU);
125 }
126
127 sprintf (buffer, "mpfr_l2b_%d_%d", beta, i);
128 if (output)
129 print_mpfr (p, buffer);
130
131 /* Check the value */
132 t = &__gmpfr_l2b[beta-2][i];
133 if (t == NULL || MPFR_PREC (t) == 0 || !mpfr_equal_p (p, t))
134 {
135 if (!output)
136 {
137 error = 1;
138 printf ("Error for constant %s\n", buffer);
139 }
140 }
141
142 if (!output)
143 mpfr_clear (p);
144 }
145 }
146
147 if (output)
148 {
149 if (printf ("const __mpfr_struct __gmpfr_l2b[BASE_MAX-1][2] = {\n")
150 < 0)
151 { fprintf (stderr, "Error in printf\n"); exit (1); }
152 for (beta = 2; beta <= BASE_MAX; beta++)
153 {
154 for (i = 0; i < 2; i++)
155 {
156 p = &l2b[beta-2][i];
157 if (printf (" %c {%3d,%2d,%3ld, (mp_limb_t *) "
158 "mpfr_l2b_%d_%d__tab }%s\n", i == 0 ? '{' : ' ',
159 (int) MPFR_PREC (p), MPFR_SIGN (p),
160 (long) MPFR_GET_EXP (p), beta, i,
161 i == 0 ? "," : beta < BASE_MAX ? " }," : " } };")
162 < 0)
163 { fprintf (stderr, "Error in printf\n"); exit (1); }
164 mpfr_clear (p);
165 }
166 }
167 }
168
169 /* If there was an error, the test fails. */
170 if (error)
171 exit (1);
172 }
173
174 int
175 main (int argc, char *argv[])
176 {
177 if (argc != 1)
178 {
179 /* Generate code that initializes the l2b constants. */
180 compute_l2b (1);
181 }
182 else
183 {
184 /* Check the l2b constants. */
185 tests_start_mpfr ();
186 compute_l2b (0);
187 tests_end_mpfr ();
188 }
189 return 0;
190 }