ref: 84f6061a92d92f6f0136f7d6ab42fa03c38d5a78
dir: /sys/src/ape/lib/openssl/crypto/bn/bn.mul/
We need * bn_mul_comba8 * bn_mul_comba4 * bn_mul_normal * bn_mul_recursive * bn_sqr_comba8 * bn_sqr_comba4 bn_sqr_normal -> BN_sqr * bn_sqr_recursive * bn_mul_low_recursive * bn_mul_low_normal * bn_mul_high * bn_mul_part_recursive # symetric but not power of 2 bn_mul_asymetric_recursive # uneven, but do the chop up.