glv_prototype.rs

pub trait GlvMul {
    // whatever trait methods you need
}

pub trait SWModelParameters {
    fn scalar_mul(thing: SWAffine<Self>, other: bits) -> SWAffine<Self> {
        // default double and add impl
    }
}

impl GlvMul for bls12_377::G1 { // or bls12_377::G1Parameters
    // stuff
}

impl SWModelParameters for bls12_377::G1Parameters {
    // other stuff here
  
    fn scalar_mul(thing: SWAffine<Self>, other: bits) -> SWAffine<Self> {
        // Glv based impl that invokes 
    }
}

//////////////////////////////////////////////////////////////
// In short_weierstrass_jacobian.rs

impl<P: SWModelParameters> SWAffine<P> {
    fn mul_bits(&self, other: bits) -> Self {
        P::scalar_mul(&self, other)
    }
}