public static func ^=(_ lhs: inout UInt128, _ rhs: UInt128) {
        let upperBits = lhs.value.upperBits ^ rhs.value.upperBits
        let lowerBits = lhs.value.lowerBits ^ rhs.value.lowerBits
        
        lhs = UInt128(upperBits: upperBits, lowerBits: lowerBits)