Function fiat_crypto::curve25519_64::fiat_25519_carry_scmul_121666

pub fn fiat_25519_carry_scmul_121666(
    out1: &mut fiat_25519_tight_field_element,
    arg1: &fiat_25519_loose_field_element
)

The function fiat_25519_carry_scmul_121666 multiplies a field element by 121666 and reduces the result.

Postconditions: eval out1 mod m = (121666 * eval arg1) mod m