bn_mul_words
r[4] = bn_mul_words(&(r[0]), a, 4, b[0]);
r[8] = bn_mul_words(&(r[0]), a, 8, b[0]);
l0 = bn_mul_words(tmp->d, sdiv->d, div_n, q);
BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w);
(void)bn_mul_words(r, a, na, 0);
rr[0] = bn_mul_words(r, a, na, b[0]);
bn_mul_words(r, a, n, b[0]);
rp[j] = bn_mul_words(rp, ap, j, ap[-1]);
ll = bn_mul_words(a->d, a->d, a->top, w);