BN_BYTES
if (BN_num_bytes(num) <= BN_BYTES) {
i = ((n - 1) / BN_BYTES) + 1;
m = ((n - 1) % (BN_BYTES));
m = BN_BYTES - 1;
atop = a->dmax * BN_BYTES;
atop = a->top * BN_BYTES;
l = a->d[i / BN_BYTES];
val = (unsigned char)(l >> (8 * (i % BN_BYTES)) & mask);
i = ((n - 1) / BN_BYTES) + 1;
m = (n - 1) % BN_BYTES;
m = BN_BYTES - 1;
m = ((BN_BYTES * 2) <= j) ? (BN_BYTES * 2) : j;
j -= (BN_BYTES * 2);
buf = malloc(BN_is_negative(a) + a->top * BN_BYTES * 2 + 2);