1 /* Generate mp_bases data.
3 Copyright 1991, 1993, 1994, 1996, 2000, 2002, 2004 Free Software Foundation,
6 This file is part of the GNU MP Library.
8 The GNU MP 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 2.1 of the License, or (at your
11 option) any later version.
13 The GNU MP 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.
18 You should have received a copy of the GNU Lesser General Public License
19 along with the GNU MP Library; see the file COPYING.LIB. If not, write to
20 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
21 MA 02110-1301, USA. */
29 double chars_per_bit_exactly;
31 int normalization_steps;
32 mpz_t big_base_inverted;
36 #define POW2_P(n) (((n) & ((n) - 1)) == 0)
39 ulog2 (unsigned int x)
42 for (i = 0; x != 0; i++)
48 generate (int limb_bits, int nail_bits, int base)
50 int numb_bits = limb_bits - nail_bits;
53 mpz_mul_2exp (t, t, numb_bits);
54 mpz_set_ui (big_base, 1L);
58 mpz_mul_ui (big_base, big_base, (long) base);
59 if (mpz_cmp (big_base, t) > 0)
64 chars_per_bit_exactly = 0.69314718055994530942 / log ((double) base);
66 mpz_ui_pow_ui (big_base, (long) base, (long) chars_per_limb);
68 normalization_steps = limb_bits - mpz_sizeinbase (big_base, 2);
71 mpz_mul_2exp (t, t, 2*limb_bits - normalization_steps);
72 mpz_tdiv_q (big_base_inverted, t, big_base);
74 mpz_mul_2exp (t, t, limb_bits);
75 mpz_sub (big_base_inverted, big_base_inverted, t);
79 header (int limb_bits, int nail_bits)
81 int numb_bits = limb_bits - nail_bits;
83 generate (limb_bits, nail_bits, 10);
85 printf ("/* This file generated by gen-bases.c - DO NOT EDIT. */\n");
87 printf ("#if GMP_NUMB_BITS != %d\n", numb_bits);
88 printf ("Error, error, this data is for %d bits\n", numb_bits);
91 printf ("/* mp_bases[10] data, as literal values */\n");
92 printf ("#define MP_BASES_CHARS_PER_LIMB_10 %d\n", chars_per_limb);
93 printf ("#define MP_BASES_BIG_BASE_10 CNST_LIMB(0x");
94 mpz_out_str (stdout, 16, big_base);
96 printf ("#define MP_BASES_BIG_BASE_INVERTED_10 CNST_LIMB(0x");
97 mpz_out_str (stdout, 16, big_base_inverted);
99 printf ("#define MP_BASES_NORMALIZATION_STEPS_10 %d\n", normalization_steps);
103 table (int limb_bits, int nail_bits)
105 int numb_bits = limb_bits - nail_bits;
108 printf ("/* This file generated by gen-bases.c - DO NOT EDIT. */\n");
110 printf ("#include \"gmp.h\"\n");
111 printf ("#include \"gmp-impl.h\"\n");
113 printf ("#if GMP_NUMB_BITS != %d\n", numb_bits);
114 printf ("Error, error, this data is for %d bits\n", numb_bits);
117 puts ("const struct bases mp_bases[257] =\n{");
118 puts (" /* 0 */ { 0, 0.0, 0 },");
119 puts (" /* 1 */ { 0, 1e37, 0 },");
120 for (base = 2; base <= 256; base++)
122 generate (limb_bits, nail_bits, base);
124 printf (" /* %3u */ { ", base);
127 printf ("%u, %.16f, 0x%x },\n",
128 chars_per_limb, chars_per_bit_exactly, ulog2 (base) - 1);
132 printf ("%u, %.16f, CNST_LIMB(0x",
133 chars_per_limb, chars_per_bit_exactly);
134 mpz_out_str (stdout, 16, big_base);
135 printf ("), CNST_LIMB(0x");
136 mpz_out_str (stdout, 16, big_base_inverted);
145 main (int argc, char **argv)
147 int limb_bits, nail_bits;
150 mpz_init (big_base_inverted);
155 fprintf (stderr, "Usage: gen-bases <header|table> <limbbits> <nailbits>\n");
159 limb_bits = atoi (argv[2]);
160 nail_bits = atoi (argv[3]);
164 || nail_bits >= limb_bits)
166 fprintf (stderr, "Invalid limb/nail bits: %d %d\n",
167 limb_bits, nail_bits);
171 if (strcmp (argv[1], "header") == 0)
172 header (limb_bits, nail_bits);
173 else if (strcmp (argv[1], "table") == 0)
174 table (limb_bits, nail_bits);
177 fprintf (stderr, "Invalid header/table choice: %s\n", argv[1]);