1 /* Test file for mpfr_log2p1.
2
3 Copyright 2001-2023 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 #include "mpfr-test.h"
24
25 #define TEST_FUNCTION mpfr_log2p1
26 #define TEST_RANDOM_EMAX 80
27 #include "tgeneric.c"
28
29 static void
special(void)30 special (void)
31 {
32 mpfr_t x;
33 int inex;
34
35 mpfr_init2 (x, MPFR_PREC_MIN);
36
37 mpfr_set_nan (x);
38 mpfr_clear_flags ();
39 inex = mpfr_log2p1 (x, x, MPFR_RNDN);
40 MPFR_ASSERTN (mpfr_nan_p (x) && inex == 0);
41 MPFR_ASSERTN (__gmpfr_flags == MPFR_FLAGS_NAN);
42
43 mpfr_set_inf (x, -1);
44 mpfr_clear_flags ();
45 inex = mpfr_log2p1 (x, x, MPFR_RNDN);
46 MPFR_ASSERTN (mpfr_nan_p (x) && inex == 0);
47 MPFR_ASSERTN (__gmpfr_flags == MPFR_FLAGS_NAN);
48
49 mpfr_set_inf (x, 1);
50 mpfr_clear_flags ();
51 inex = mpfr_log2p1 (x, x, MPFR_RNDN);
52 MPFR_ASSERTN (mpfr_inf_p (x) && mpfr_sgn (x) > 0 && inex == 0);
53 MPFR_ASSERTN (__gmpfr_flags == 0);
54
55 mpfr_set_ui (x, 0, MPFR_RNDN);
56 mpfr_clear_flags ();
57 inex = mpfr_log2p1 (x, x, MPFR_RNDN);
58 MPFR_ASSERTN (mpfr_cmp_ui (x, 0) == 0 && MPFR_IS_POS (x) && inex == 0);
59 MPFR_ASSERTN (__gmpfr_flags == 0);
60 mpfr_neg (x, x, MPFR_RNDN);
61 mpfr_clear_flags ();
62 inex = mpfr_log2p1 (x, x, MPFR_RNDN);
63 MPFR_ASSERTN (mpfr_cmp_ui (x, 0) == 0 && MPFR_IS_NEG (x) && inex == 0);
64 MPFR_ASSERTN (__gmpfr_flags == 0);
65
66 mpfr_set_si (x, -1, MPFR_RNDN);
67 mpfr_clear_flags ();
68 inex = mpfr_log2p1 (x, x, MPFR_RNDN);
69 MPFR_ASSERTN (mpfr_inf_p (x) && mpfr_sgn (x) < 0 && inex == 0);
70 MPFR_ASSERTN (__gmpfr_flags == MPFR_FLAGS_DIVBY0);
71
72 mpfr_set_si (x, -2, MPFR_RNDN);
73 mpfr_clear_flags ();
74 inex = mpfr_log2p1 (x, x, MPFR_RNDN);
75 MPFR_ASSERTN (mpfr_nan_p (x) && inex == 0);
76 MPFR_ASSERTN (__gmpfr_flags == MPFR_FLAGS_NAN);
77
78 /* include one hard-coded test */
79 mpfr_set_prec (x, 32);
80 mpfr_set_ui (x, 17, MPFR_RNDN);
81 inex = mpfr_log2p1 (x, x, MPFR_RNDN);
82 MPFR_ASSERTN (mpfr_cmp_ui_2exp (x, 1119355719UL, -28) == 0);
83 MPFR_ASSERTN (inex < 0);
84
85 mpfr_clear (x);
86 }
87
88 /* check exact cases, when 1+x = 2^k */
89 static void
check_exact(void)90 check_exact (void)
91 {
92 mpfr_exp_t k;
93 mpfr_t x;
94 int inex, r;
95
96 #define KMAX 100
97 mpfr_init2 (x, KMAX);
98 for (k = -KMAX; k <= KMAX; k++)
99 RND_LOOP (r)
100 {
101 mpfr_set_ui_2exp (x, 1, k, (mpfr_rnd_t) r);
102 inex = mpfr_sub_ui (x, x, 1, (mpfr_rnd_t) r);
103 MPFR_ASSERTN(inex == 0);
104 inex = mpfr_log2p1 (x, x, (mpfr_rnd_t) r);
105 MPFR_ASSERTN(mpfr_cmp_si0 (x, k) == 0);
106 MPFR_ASSERTN(inex == 0);
107 }
108 mpfr_clear (x);
109 }
110
111 int
main(int argc,char * argv[])112 main (int argc, char *argv[])
113 {
114 tests_start_mpfr ();
115
116 special ();
117
118 check_exact ();
119
120 test_generic (MPFR_PREC_MIN, 100, 50);
121
122 tests_end_mpfr ();
123 return 0;
124 }
125