dsimp [toCNF]
entry : Entrypoint Nat
⊢ (toCNF entry).unsat ↔ entry.unsat
entry : Entrypoint Nat
⊢ (CNF.relabel toCNF.inj
        ([(Sum.inr ⟨entry.ref.gate, ⋯⟩, true)] ::
          (toCNF.go entry.aig entry.ref.gate ⋯ (toCNF.State.empty entry.aig)).val.cnf)).unsat ↔
    entry.unsat