benchmark.cpp

#include <immintrin.h>
#include <vector>
#include <inttypes.h>
#include <chrono>
#include <iostream>
using namespace std;

void run_million_adds() {
  vector<uint64_t> test1(1000000);

  for (int i = 2; i < 1000000; ++i){
    test1[i + 1] = test1[i - 1] + test1[i];
  }
}

void run_million_pext() {
  vector<uint64_t> test1(1000000);

  for (int i = 2; i < 1000000; ++i){
    test1[i + 1] = _pext_u64(test1[i - 1], test1[i]) + i;
  }
}

int main(int argc, char const *argv[])
{
  for (int i = 0; i < 1000; ++i)
  {
    auto start = std::chrono::high_resolution_clock::now();
    run_million_adds();
    auto end_add = std::chrono::high_resolution_clock::now();
    run_million_pext();
    auto end_pext = std::chrono::high_resolution_clock::now();
    cout << "ADD: " << ((std::chrono::duration<double>)(end_add - start)).count() << endl;
    cout << "PEXT: " << ((std::chrono::duration<double>)(end_pext - end_add)).count() << endl;
  }
  return 0;
}