#include "macros.h"
+#define NBITS (sizeof (long long int) * CHAR_BIT)
+
static int
naive (long long int i)
{
unsigned long long int j;
- for (j = 0; j < CHAR_BIT * sizeof i; j++)
+ for (j = 0; j < NBITS; j++)
if (i & (1ULL << j))
return j + 1;
return 0;
int
main (int argc, char *argv[])
{
- long long int i;
+ long long int x;
+ int i;
- for (i = -128; i <= 128; i++)
- ASSERT (ffsll (i) == naive (i));
- for (i = 0; i < CHAR_BIT * sizeof i; i++)
+ for (x = -128; x <= 128; x++)
+ ASSERT (ffsll (x) == naive (x));
+ for (i = 0; i < NBITS; i++)
{
ASSERT (ffsll (1ULL << i) == naive (1ULL << i));
ASSERT (ffsll (1ULL << i) == i + 1);
+ ASSERT (ffsll (-1ULL << i) == i + 1);
+ }
+ for (i = 0; i < NBITS - 1; i++)
+ {
+ ASSERT (ffsll (3ULL << i) == i + 1);
+ ASSERT (ffsll (-3ULL << i) == i + 1);
+ }
+ for (i = 0; i < NBITS - 2; i++)
+ {
+ ASSERT (ffsll (5ULL << i) == i + 1);
+ ASSERT (ffsll (-5ULL << i) == i + 1);
+ ASSERT (ffsll (7ULL << i) == i + 1);
+ ASSERT (ffsll (-7ULL << i) == i + 1);
}
return 0;
}