bench/product_threshold.cpp

#include <iostream>
#include <Eigen/Core>
#include <bench/BenchTimer.h>

using namespace Eigen;
using namespace std;

#define END 9

template <int S>
struct map_size {
  enum { ret = S };
};
template <>
struct map_size<10> {
  enum { ret = 20 };
};
template <>
struct map_size<11> {
  enum { ret = 50 };
};
template <>
struct map_size<12> {
  enum { ret = 100 };
};
template <>
struct map_size<13> {
  enum { ret = 300 };
};

template <int M, int N, int K>
struct alt_prod {
  enum {
    ret = M == 1 && N == 1 ? InnerProduct
          : K == 1         ? OuterProduct
          : M == 1         ? GemvProduct
          : N == 1         ? GemvProduct
                           : GemmProduct
  };
};

void print_mode(int mode) {
  if (mode == InnerProduct) std::cout << "i";
  if (mode == OuterProduct) std::cout << "o";
  if (mode == CoeffBasedProductMode) std::cout << "c";
  if (mode == LazyCoeffBasedProductMode) std::cout << "l";
  if (mode == GemvProduct) std::cout << "v";
  if (mode == GemmProduct) std::cout << "m";
}

template <int Mode, typename Lhs, typename Rhs, typename Res>
EIGEN_DONT_INLINE void prod(const Lhs& a, const Rhs& b, Res& c) {
  c.noalias() += typename ProductReturnType<Lhs, Rhs, Mode>::Type(a, b);
}

template <int M, int N, int K, typename Scalar, int Mode>
EIGEN_DONT_INLINE void bench_prod() {
  typedef Matrix<Scalar, M, K> Lhs;
  Lhs a;
  a.setRandom();
  typedef Matrix<Scalar, K, N> Rhs;
  Rhs b;
  b.setRandom();
  typedef Matrix<Scalar, M, N> Res;
  Res c;
  c.setRandom();

  BenchTimer t;
  double n = 2. * double(M) * double(N) * double(K);
  int rep = 100000. / n;
  rep /= 2;
  if (rep < 1) rep = 1;
  do {
    rep *= 2;
    t.reset();
    BENCH(t, 1, rep, prod<CoeffBasedProductMode>(a, b, c));
  } while (t.best() < 0.1);

  t.reset();
  BENCH(t, 5, rep, prod<Mode>(a, b, c));

  print_mode(Mode);
  std::cout << int(1e-6 * n * rep / t.best()) << "\t";
}

template <int N>
struct print_n;
template <int M, int N, int K>
struct loop_on_m;
template <int M, int N, int K, typename Scalar, int Mode>
struct loop_on_n;

template <int M, int N, int K>
struct loop_on_k {
  static void run() {
    std::cout << "K=" << K << "\t";
    print_n<N>::run();
    std::cout << "\n";

    loop_on_m<M, N, K>::run();
    std::cout << "\n\n";

    loop_on_k<M, N, K + 1>::run();
  }
};

template <int M, int N>
struct loop_on_k<M, N, END> {
  static void run() {}
};

template <int M, int N, int K>
struct loop_on_m {
  static void run() {
    std::cout << M << "f\t";
    loop_on_n<M, N, K, float, CoeffBasedProductMode>::run();
    std::cout << "\n";

    std::cout << M << "f\t";
    loop_on_n<M, N, K, float, -1>::run();
    std::cout << "\n";

    loop_on_m<M + 1, N, K>::run();
  }
};

template <int N, int K>
struct loop_on_m<END, N, K> {
  static void run() {}
};

template <int M, int N, int K, typename Scalar, int Mode>
struct loop_on_n {
  static void run() {
    bench_prod<M, N, K, Scalar, Mode == -1 ? alt_prod<M, N, K>::ret : Mode>();

    loop_on_n<M, N + 1, K, Scalar, Mode>::run();
  }
};

template <int M, int K, typename Scalar, int Mode>
struct loop_on_n<M, END, K, Scalar, Mode> {
  static void run() {}
};

template <int N>
struct print_n {
  static void run() {
    std::cout << map_size<N>::ret << "\t";
    print_n<N + 1>::run();
  }
};

template <>
struct print_n<END> {
  static void run() {}
};

int main() {
  loop_on_k<1, 1, 1>::run();

  return 0;
}