return pi->bits[bit/MALLOC_BITS] & (1<<(bit%MALLOC_BITS));
return pi->bits[bit/MALLOC_BITS] & (1UL<<(bit%MALLOC_BITS));
tst_bit(pi, bit)    struct pginfo *pi;    int bit;{    return pi->bits[bit/MALLOC_BITS] & (1<<(bit%MALLOC_BITS));}