Fix minor bug where constant_affine_point is called on zero

This commit is contained in:
wborgeaud 2022-07-23 09:18:41 +02:00
parent 60227b9828
commit bbc2ff27ab

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@ -40,14 +40,18 @@ pub fn fixed_base_curve_mul_circuit<C: Curve, F: RichField + Extendable<D>, cons
// `s * P = sum s_i * P_i` with `P_i = (16^i) * P` and `s = sum s_i * (16^i)`.
for (limb, point) in limbs.into_iter().zip(scaled_base) {
// `muls_point[t] = t * P_i` for `t=0..16`.
let muls_point = (0..16)
let mut muls_point = (0..16)
.scan(AffinePoint::ZERO, |acc, _| {
let tmp = *acc;
*acc = (point + *acc).to_affine();
Some(tmp)
})
// First element if zero, so we skip it since `constant_affine_point` takes non-zero input.
.skip(1)
.map(|p| builder.constant_affine_point(p))
.collect::<Vec<_>>();
// We add back a point in position 0. `limb == zero` is checked below, so this point can be arbitrary.
muls_point.insert(0, muls_point[0].clone());
let is_zero = builder.is_equal(limb, zero);
let should_add = builder.not(is_zero);
// `r = s_i * P_i`