benchmark.cpp

// g++ -O3 -DNDEBUG -DMATSIZE=<x> benchmark.cpp -o benchmark && time ./benchmark

#include <iostream>

#include <Eigen/Core>

#ifndef MATSIZE
#define MATSIZE 3
#endif

using namespace std;
using namespace Eigen;

#ifndef REPEAT
#define REPEAT 40000000
#endif

#ifndef SCALAR
#define SCALAR double
#endif

int main(int argc, char *argv[]) {
  Matrix<SCALAR, MATSIZE, MATSIZE> I = Matrix<SCALAR, MATSIZE, MATSIZE>::Ones();
  Matrix<SCALAR, MATSIZE, MATSIZE> m;
  for (int i = 0; i < MATSIZE; i++)
    for (int j = 0; j < MATSIZE; j++) {
      m(i, j) = (i + MATSIZE * j);
    }
  asm("#begin");
  for (int a = 0; a < REPEAT; a++) {
    m = Matrix<SCALAR, MATSIZE, MATSIZE>::Ones() + 0.00005 * (m + (m * m));
  }
  asm("#end");
  cout << m << endl;
  return 0;
}