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wborgeaud 2021-07-23 15:01:45 +02:00
parent f325586beb
commit 19140e39b2

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@ -35,8 +35,7 @@ impl<F: Extendable<D>, const D: usize> CircuitBuilder<F, D> {
// The evaluation vector needs to be reordered first.
let mut evals = last_evals.to_vec();
reverse_index_bits_in_place(&mut evals);
// Want `g^(arity - rev_old_x_index)` as in the out-of-circuit version.
// Compute it as `g^(arity-1-rev_old_x_index) * g`, where the first term is gotten using two's complement.
// Want `g^(arity - rev_old_x_index)` as in the out-of-circuit version. Compute it as `(g^-1)^rev_old_x_index`.
let start = self.exp_from_bits(g_inv_t, old_x_index_bits.iter().rev());
let coset_start = self.mul(start, x);