You can hint the compiler: https://en.cppreference.com/w/cpp/language/attributes/likely https://en.cppreference.com/w/cpp/language/attributes/likely Or you can

You can hint the compiler: https://en.cppreference.com/w/cpp/language/attributes/likely https://en.cppreference.com/w/cpp/language/attributes/likely Or you can use profile directed optimization, as others mentioned. In my test recently it reduced branches as a whole by 30%, according to perf stat ./a.out