2 * Copyright (C) 2012 Free Software Foundation, Inc.
4 * This program is free software: you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 3 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>. */
17 /* Written by Eric Blake. */
21 #include "count-leading-zeros.h"
28 #define UINT_BIT (sizeof (unsigned int) * CHAR_BIT)
29 #define ULONG_BIT (sizeof (unsigned long int) * CHAR_BIT)
30 #define ULLONG_BIT (sizeof (unsigned long long int) * CHAR_BIT)
33 # define HALF (1ULL << (sizeof (unsigned long long int) * CHAR_BIT - 1))
34 # define ULLONG_MAX (HALF - 1 + HALF)
38 main (int argc, char *argv[])
42 #define TEST_COUNT_LEADING_ZEROS(FUNC, TYPE, BITS, MAX, ONE) \
43 ASSERT (FUNC (0) == BITS); \
44 for (i = 0; i < BITS; i++) \
46 ASSERT (FUNC (ONE << i) == BITS - i - 1); \
47 for (j = 0; j < i; j++) \
48 ASSERT (FUNC ((ONE << i) | (ONE << j)) == BITS - i - 1);\
50 for (i = 0; i < 1000; i++) \
52 TYPE value = rand () ^ (rand () << 31 << 1); \
54 for (j = 0; j < BITS; j++) \
55 if (value & (ONE << j)) \
56 count = BITS - j - 1; \
57 ASSERT (count == FUNC (value)); \
59 ASSERT (FUNC (MAX) == 0);
61 TEST_COUNT_LEADING_ZEROS (count_leading_zeros, unsigned int,
62 UINT_BIT, UINT_MAX, 1U);
63 TEST_COUNT_LEADING_ZEROS (count_leading_zeros_l, unsigned long int,
64 ULONG_BIT, ULONG_MAX, 1UL);
65 #ifdef HAVE_UNSIGNED_LONG_LONG_INT
66 TEST_COUNT_LEADING_ZEROS (count_leading_zeros_ll, unsigned long long int,
67 ULLONG_BIT, ULLONG_MAX, 1ULL);