pub fn field_inv<const LIMBS: usize>(
a: &FieldElement<LIMBS>,
p: &[u64; LIMBS],
) -> FieldElement<LIMBS>Expand description
Modular inverse: a^{-1} mod p via Fermat’s little theorem: a^{p-2} mod p. Constant-time (fixed sequence of square + conditional multiply for every bit).