Избежать оптимизации

https://habr.com/ru/companies/yadro/articles/1001574/#comment_29557066

https://godbolt.org/z/cbssKjbfx

int popcnt_deoptimized(unsigned int var) {

  int count = 0;

  while (var) {

    unsigned int two = 2; asm ("" : "+rm"(two));

    if (var % two == 1)

        count++;

    var = var / two;

  }

  return count;

}