SHIFT_WORD
#define BIT_CLEAR(a,n) ((a)[(n)>>SHIFT_WORD] &= ~(1L << ((n) & 31)))
#define BIT_SET(a,n) ((a)[(n)>>SHIFT_WORD] |= (1L << ((n) & 31)))
#define BIT_TEST(a,n) ((a)[(n)>>SHIFT_WORD] & (1L << ((n) & 31)))
largewords = ((power * power) >> (SHIFT_WORD - TEST_POWER));
tinybits = tinywords << SHIFT_WORD;
smallbits = smallwords << SHIFT_WORD;
largebits = largewords << SHIFT_WORD;