CHOOSE_LOAD_FUNC
func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_word);
func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_half);
func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte);
func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte_msh);