Function live_sbox_evaluations 

pub const fn live_sbox_evaluations() -> usize

Count the S-box evaluations that are neither constant nor unobserved.

Works backwards from the 18 kept bytes: a MixColumns output needs its whole column, a SubBytes output needs its ShiftRows source, and the word mix is a permutation. Works forwards with KNOWN to drop constant S-boxes. The result is a structural planning count, not a synthesis measurement.