#include <chrono>
#include <iostream>

static unsigned long long total = 0;

__attribute__((__noinline__)) void by_ref(const std::chrono::system_clock::time_point& t)
{
  total += (std::chrono::system_clock::now() - t).count();
}

__attribute__((__noinline__)) void by_value(std::chrono::system_clock::time_point t)
{
  total += (std::chrono::system_clock::now() - t).count();
}

int main(void)
{
  std::chrono::system_clock::time_point t = std::chrono::system_clock::now();
  std::cout << "size: " << sizeof(t) << std::endl;

  const unsigned long long tries = 10000000;
  auto before = std::chrono::high_resolution_clock::now();
  for (unsigned long long i = 0; i < tries; ++i)
    by_ref(t);
  auto diff = std::chrono::high_resolution_clock::now() - before;
  std::cout << "by_ref: " << diff.count() << std::endl;

  before = std::chrono::high_resolution_clock::now();
  for (unsigned long long i = 0; i < tries; ++i)
    by_value(t);
  diff = std::chrono::high_resolution_clock::now() - before;
  std::cout << "by_value: " << diff.count() << std::endl;

  std::cout << "total: " << total << std::endl;

  return 0;
}