Function clock_permute 

pub fn clock_permute(state: &mut [u64; 8])

Apply ClockPermute to the 8-word state (16 rounds).

Each round applies:

• Step A: S[i] = (S[i] + S[(i+1) mod 8]) * P0 (wrapping arithmetic)
• Step B: S[i] = ROTL(S[i] ⊕ S[(i+3) mod 8], R[(round+i) mod 16])
• Step C: Swap pairs (S[1]↔S[5], S[2]↔S[6], S[3]↔S[7])

Arguments

• state - Mutable reference to 8 u64 words representing the hash state

Panics

This function will panic if state.len() != 8.