| /* Test of integer_length_ll(). |
| Copyright (C) 2011-2020 Free Software Foundation, Inc. |
| |
| This program is free software: you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <https://www.gnu.org/licenses/>. */ |
| |
| #include <config.h> |
| |
| #include "integer_length.h" |
| |
| #include <limits.h> |
| |
| #include "macros.h" |
| |
| #define NBITS (sizeof (unsigned long long) * CHAR_BIT) |
| |
| static int |
| naive (unsigned long long x) |
| { |
| int j; |
| for (j = NBITS - 1; j >= 0; j--) |
| if (x & (1ULL << j)) |
| return j + 1; |
| return 0; |
| } |
| |
| int |
| main (int argc, char *argv[]) |
| { |
| unsigned long x; |
| int i; |
| |
| for (x = 0; x <= 256; x++) |
| ASSERT (integer_length_ll (x) == naive (x)); |
| for (i = 0; i < NBITS; i++) |
| { |
| ASSERT (integer_length_ll (1ULL << i) == naive (1ULL << i)); |
| ASSERT (integer_length_ll (1ULL << i) == i + 1); |
| ASSERT (integer_length_ll (-1ULL << i) == NBITS); |
| } |
| for (i = 0; i < NBITS - 1; i++) |
| ASSERT (integer_length_ll (3ULL << i) == i + 2); |
| for (i = 0; i < NBITS - 2; i++) |
| ASSERT (integer_length_ll (-3ULL << i) == NBITS); |
| for (i = 0; i < NBITS - 2; i++) |
| { |
| ASSERT (integer_length_ll (5ULL << i) == i + 3); |
| ASSERT (integer_length_ll (7ULL << i) == i + 3); |
| } |
| for (i = 0; i < NBITS - 3; i++) |
| { |
| ASSERT (integer_length_ll (-5ULL << i) == NBITS); |
| ASSERT (integer_length_ll (-7ULL << i) == NBITS); |
| } |
| return 0; |
| } |