CSAPP 性能优化实验室

void vec_sum(vec_ptr v, data_t *dest) {
    int length = vec_length(v);
    *dest = 0;
    for (int i = 0; i < length; i++) {
        data_t val;
        get_vec_element(v, i, &val);
        *dest += val;
    }
}