1/* Test file for mpfr_log2p1.
2
3Copyright 2001-2023 Free Software Foundation, Inc.
4Contributed by the AriC and Caramba projects, INRIA.
5
6This file is part of the GNU MPFR Library.
7
8The GNU MPFR Library is free software; you can redistribute it and/or modify
9it under the terms of the GNU Lesser General Public License as published by
10the Free Software Foundation; either version 3 of the License, or (at your
11option) any later version.
12
13The GNU MPFR Library is distributed in the hope that it will be useful, but
14WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
16License for more details.
17
18You should have received a copy of the GNU Lesser General Public License
19along with the GNU MPFR Library; see the file COPYING.LESSER.  If not, see
20https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
2151 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
29static void
30special (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 */
89static void
90check_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
111int
112main (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