int poly_degree_to_max_mod_bits()

in src/hit/common.cpp [127:151]

• 20 lines of code
• 8 McCabe index (conditional complexity)

    int poly_degree_to_max_mod_bits(int poly_modulus_degree) {
        switch (poly_modulus_degree) {
            case 1024:
                return 27;
            case 2048:
                return 54;
            case 4096:
                return 109;
            case 8192:
                return 218;
            case 16384:
                return 438;
            case 32768:
                return 881;
            case 65536:
                // extrapolating a best-fit line for the above data points:
                // mod_bits <= 0.0269*poly_modulus_degree-1.4428

                // SEAL will throw an exception when poly degree is 131072 or larger
                // (which corresponds to the 262144th cyclotomic ring)
                return 1761;
            default:
                LOG_AND_THROW_STREAM("poly_modulus_degree " << poly_modulus_degree << " not supported");
        }
    }