1 /* Generate Fibonacci table data.
2
3 Copyright 2001, 2002, 2004 Free Software Foundation, Inc.
4
5 This file is part of the GNU MP Library.
6
7 The GNU MP Library is free software; you can redistribute it and/or modify
8 it under the terms of the GNU Lesser General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or (at your
10 option) any later version.
11
12 The GNU MP Library is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
15 License for more details.
16
17 You should have received a copy of the GNU Lesser General Public License
18 along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */
19
20 #include <stdio.h>
21 #include "dumbmp.c"
22
23 mpz_t *f;
24 int fnum, fib_limit, luc_limit;
25
26 void
generate(int numb_bits)27 generate (int numb_bits)
28 {
29 mpz_t limit, l;
30 int falloc, i;
31
32 mpz_init_set_ui (limit, 1L);
33 mpz_mul_2exp (limit, limit, numb_bits);
34
35 /* fib(2n) > 2^n, so use 2n as a limit for the table size */
36 falloc = 2 * numb_bits;
37 f = (mpz_t *) xmalloc (falloc * sizeof (*f));
38
39 mpz_init_set_ui (f[0], 1L); /* F[-1] */
40 mpz_init_set_ui (f[1], 0L); /* F[0] */
41
42 mpz_init (l);
43
44 for (i = 2; ; i++)
45 {
46 ASSERT (i < falloc);
47
48 /* F[i] = F[i-1] + F[i-2] */
49 mpz_init (f[i]);
50 mpz_add (f[i], f[i-1], f[i-2]);
51 if (mpz_cmp (f[i], limit) >= 0)
52 break;
53
54 fnum = i+1;
55 fib_limit = i-1;
56
57 /* L[i] = F[i]+2*F[i-1] */
58 mpz_add (l, f[i], f[i-1]);
59 mpz_add (l, l, f[i-1]);
60
61 if (mpz_cmp (l, limit) < 0)
62 luc_limit = i-1;
63 }
64
65 mpz_clear (limit);
66 }
67
68
69 void
header(int numb_bits)70 header (int numb_bits)
71 {
72 printf ("/* This file generated by gen-fib.c - DO NOT EDIT. */\n");
73 printf ("\n");
74 printf ("#if GMP_NUMB_BITS != %d\n", numb_bits);
75 printf ("Error, error, this data is for %d bits\n", numb_bits);
76 printf ("#endif\n");
77 printf ("\n");
78 printf ("#define FIB_TABLE_LIMIT %d\n", fib_limit);
79 printf ("#define FIB_TABLE_LUCNUM_LIMIT %d\n", luc_limit);
80 }
81
82 void
table(int numb_bits)83 table (int numb_bits)
84 {
85 int i;
86
87 printf ("/* This file generated by gen-fib.c - DO NOT EDIT. */\n");
88 printf ("\n");
89 printf ("#include \"gmp.h\"\n");
90 printf ("#include \"gmp-impl.h\"\n");
91 printf ("\n");
92 printf ("#if GMP_NUMB_BITS != %d\n", numb_bits);
93 printf ("Error, error, this data is for %d bits\n", numb_bits);
94 printf ("#endif\n");
95 printf ("\n");
96 printf ("const mp_limb_t\n");
97 printf ("__gmp_fib_table[FIB_TABLE_LIMIT+2] = {\n");
98
99 for (i = 0; i < fnum; i++)
100 {
101 printf (" CNST_LIMB (0x");
102 mpz_out_str (stdout, 16, f[i]);
103 printf ("), /* %d */\n", i-1);
104 }
105 printf ("};\n");
106 }
107
108 int
main(int argc,char * argv[])109 main (int argc, char *argv[])
110 {
111 int limb_bits, nail_bits, numb_bits;
112
113 if (argc != 4)
114 {
115 fprintf (stderr, "Usage: gen-bases <header|table> <limbbits> <nailbits>\n");
116 exit (1);
117 }
118
119 limb_bits = atoi (argv[2]);
120 nail_bits = atoi (argv[3]);
121
122 if (limb_bits <= 0
123 || nail_bits < 0
124 || nail_bits >= limb_bits)
125 {
126 fprintf (stderr, "Invalid limb/nail bits: %d %d\n",
127 limb_bits, nail_bits);
128 exit (1);
129 }
130 numb_bits = limb_bits - nail_bits;
131
132 generate (numb_bits);
133
134 if (strcmp (argv[1], "header") == 0)
135 header (numb_bits);
136 else if (strcmp (argv[1], "table") == 0)
137 table (numb_bits);
138 else
139 {
140 fprintf (stderr, "Invalid header/table choice: %s\n", argv[1]);
141 exit (1);
142 }
143
144 return 0;
145 }
146