Getting started with the codegen

$ codegen_arm64 --trustzone test.edl 

    enclave {
        trusted {
            public void enclave_helloworld(
                    int idata,
                    [in, size=data_in_size]unsigned char* data_in,
                    size_t data_in_size,
                    [out, size=data_out_size]unsigned char** data_out,
                    size_t data_out_size,
                    [in, out]unsigned char** data_in_out);
        };

        untrusted {
            void host_helloworld();
        };
    };

    enclave {
        trusted {
            public void enclave_helloworld(
                    int idata,
                    [in, size=data_in_size]unsigned char* data_in,
                    size_t data_in_size,
                    [out, size=data_out_size]unsigned char** data_out,
                    size_t data_out_size,
                    [in, out]unsigned char** data_in_out);
        };
    };