I was able to explode

(exp_x ^ sign_x(0 | -1) + exp_y ^ sign_y(0 | -1) + correction) ^ sign_res(0 | -1)

(from the multiplication logic) to

(exp_x * sign_y(1 | -1)) + (exp_y * sign_x(1 | -1)) + (sign_x(0 | 1) * sign_y(1 | -1)) + (sign_y(0 | 1) * sign_x(1 | -1)) + (correction * sign_res(1 | -1)) + sign_res(0 | -1)

, but I'm not sure if it can be simplified back down to something less than the original.