1 /* Test mpz_sizeinbase.
2
3 Copyright 2001, 2002 Free Software Foundation, Inc.
4
5 This file is part of the GNU MP Library test suite.
6
7 The GNU MP Library test suite is free software; you can redistribute it
8 and/or modify it under the terms of the GNU General Public License as
9 published by the Free Software Foundation; either version 3 of the License,
10 or (at your option) any later version.
11
12 The GNU MP Library test suite is distributed in the hope that it will be
13 useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
15 Public License for more details.
16
17 You should have received a copy of the GNU General Public License along with
18 the GNU MP Library test suite. If not, see https://www.gnu.org/licenses/. */
19
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include "gmp-impl.h"
23 #include "tests.h"
24
25
26 #if 0
27 /* Disabled due to the bogosity of trying to fake an _mp_d pointer to
28 below an object. Has been seen to fail on a hppa system and on ia64. */
29
30
31 /* Create a fake mpz consisting of just a single 1 bit, with totbits being
32 the total number of bits, inclusive of that 1 bit. */
33 void
34 mpz_fake_bits (mpz_ptr z, unsigned long totbits)
35 {
36 static mp_limb_t n;
37 unsigned long zero_bits, zero_limbs;
38
39 zero_bits = totbits - 1;
40 zero_limbs = zero_bits / GMP_NUMB_BITS;
41 zero_bits %= GMP_NUMB_BITS;
42
43 SIZ(z) = zero_limbs + 1;
44 PTR(z) = (&n) - (SIZ(z) - 1);
45 n = CNST_LIMB(1) << zero_bits;
46
47 ASSERT_ALWAYS (mpz_sizeinbase (z, 2) == totbits);
48 }
49
50
51 /* This was seen to fail on a GNU/Linux powerpc32 with gcc 2.95.2,
52 apparently due to a doubtful value of mp_bases[10].chars_per_bit_exactly
53 (0X1.34413509F79FDP-2 whereas 0X1.34413509F79FFP-2 is believed correct).
54 Presumably this is a glibc problem when gcc converts the decimal string
55 in mp_bases.c, or maybe it's only a function of the rounding mode during
56 compilation. */
57 void
58 check_sample (void)
59 {
60 unsigned long totbits = 198096465;
61 int base = 10;
62 size_t want = 59632979;
63 size_t got;
64 mpz_t z;
65
66 mpz_fake_bits (z, totbits);
67 got = mpz_sizeinbase (z, base);
68 if (got != want)
69 {
70 printf ("mpz_sizeinbase\n");
71 printf (" base %d\n", base);
72 printf (" totbits %lu\n", totbits);
73 printf (" got %u\n", got);
74 printf (" want %u\n", want);
75 abort ();
76 }
77 }
78 #endif
79
80 int
main(void)81 main (void)
82 {
83 tests_start ();
84
85 /* check_sample (); */
86
87 tests_end ();
88 exit (0);
89 }
90