tests/test-count-one-bits.c

   1 /*
   2  * Copyright (C) 2007-2025 Free Software Foundation, Inc.
   3  *
   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.
   8  *
   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.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Ben Pfaff.  */
  18
  19 #include <config.h>
  20
  21 #include "count-one-bits.h"
  22
  23 #include <limits.h>
  24 #include <stdio.h>
  25
  26 #include "macros.h"
  27
  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)
  31
  32 int
  33 main (int argc, char *argv[])
  34 {
  35   int i, j;
  36
  37 #define TEST_COUNT_ONE_BITS(FUNC, TYPE, BITS, MAX, ONE)   \
  38   ASSERT (FUNC (0) == 0);                                 \
  39   for (i = 0; i < BITS; i++)                              \
  40     {                                                     \
  41       ASSERT (FUNC (ONE << i) == 1);                      \
  42       for (j = i + 1; j < BITS; j++)                      \
  43         ASSERT (FUNC ((ONE << i) | (ONE << j)) == 2);     \
  44     }                                                     \
  45   for (i = 0; i < 1000; i++)                              \
  46     {                                                     \
  47       /* RAND_MAX is most often 0x7fff or 0x7fffffff.  */ \
  48       TYPE value =                                        \
  49         (RAND_MAX <= 0xffff                               \
  50          ? ((TYPE) rand () >> 3)                          \
  51            ^ (((TYPE) rand () >> 3) << 12)                \
  52            ^ (((TYPE) rand () >> 3) << 24)                \
  53            ^ (((TYPE) rand () >> 3) << 30 << 6)           \
  54            ^ (((TYPE) rand () >> 3) << 30 << 18)          \
  55            ^ (((TYPE) rand () >> 3) << 30 << 30)          \
  56          : ((TYPE) rand () >> 3)                          \
  57            ^ (((TYPE) rand () >> 3) << 22)                \
  58            ^ (((TYPE) rand () >> 3) << 22 << 22));        \
  59       int count = 0;                                      \
  60       for (j = 0; j < BITS; j++)                          \
  61         count += (value & (ONE << j)) != 0;               \
  62       ASSERT (count == FUNC (value));                     \
  63     }                                                     \
  64   ASSERT (FUNC (MAX) == BITS);
  65
  66   TEST_COUNT_ONE_BITS (count_one_bits, unsigned int, UINT_BIT, UINT_MAX, 1U);
  67   TEST_COUNT_ONE_BITS (count_one_bits_l, unsigned long int,
  68                        ULONG_BIT, ULONG_MAX, 1UL);
  69   TEST_COUNT_ONE_BITS (count_one_bits_ll, unsigned long long int,
  70                        ULLONG_BIT, ULLONG_MAX, 1ULL);
  71
  72   return test_exit_status;
  73 }