1 files changed, 128 insertions, 0 deletions
diff --git a/bench/bench_gemm.cpp b/bench/bench_gemm.cpp
new file mode 100644
index 000000000..653a880a8
--- /dev/null
+++ b/bench/bench_gemm.cpp
@@ -0,0 +1,128 @@
+
+// g++-4.4 bench_gemm.cpp -I .. -O2 -DNDEBUG -lrt -fopenmp && OMP_NUM_THREADS=2  ./a.out
+// icpc bench_gemm.cpp -I .. -O3 -DNDEBUG -lrt -openmp  && OMP_NUM_THREADS=2  ./a.out
+
+#include <Eigen/Core>
+
+#include <bench/BenchTimer.h>
+
+using namespace std;
+using namespace Eigen;
+
+#ifndef SCALAR
+#define SCALAR float
+#endif
+
+typedef SCALAR Scalar;
+typedef Matrix<Scalar,Dynamic,Dynamic> M;
+
+#ifdef HAVE_BLAS
+
+extern "C" {
+  #include <bench/btl/libs/C_BLAS/blas.h>
+
+  void sgemm_kernel(int actual_mc, int cols, int actual_kc, float alpha,
+                    float* blockA, float* blockB, float* res, int resStride);
+  void sgemm_oncopy(int actual_kc, int cols, const float* rhs, int rhsStride, float* blockB);
+  void sgemm_itcopy(int actual_kc, int cols, const float* rhs, int rhsStride, float* blockB);
+}
+
+static float fone = 1;
+static float fzero = 0;
+static double done = 1;
+static double szero = 0;
+static char notrans = 'N';
+static char trans = 'T';
+static char nonunit = 'N';
+static char lower = 'L';
+static char right = 'R';
+static int intone = 1;
+
+void blas_gemm(const MatrixXf& a, const MatrixXf& b, MatrixXf& c)
+{
+  int M = c.rows(); int N = c.cols(); int K = a.cols();
+  int lda = a.rows(); int ldb = b.rows(); int ldc = c.rows();
+
+  sgemm_(&notrans,&notrans,&M,&N,&K,&fone,
+         const_cast<float*>(a.data()),&lda,
+         const_cast<float*>(b.data()),&ldb,&fone,
+         c.data(),&ldc);
+}
+
+void blas_gemm(const MatrixXd& a, const MatrixXd& b, MatrixXd& c)
+{
+  int M = c.rows(); int N = c.cols(); int K = a.cols();
+  int lda = a.rows(); int ldb = b.rows(); int ldc = c.rows();
+
+  dgemm_(&notrans,&notrans,&M,&N,&K,&done,
+         const_cast<double*>(a.data()),&lda,
+         const_cast<double*>(b.data()),&ldb,&done,
+         c.data(),&ldc);
+}
+
+#endif
+
+void gemm(const M& a, const M& b, M& c)
+{
+  c.noalias() += a * b;
+}
+
+int main(int argc, char ** argv)
+{
+  int rep = 1;    // number of repetitions per try
+  int tries = 5;  // number of tries, we keep the best
+
+  int s = 2048;
+  int m = s;
+  int n = s;
+  int p = s;
+  M a(m,n); a.setRandom();
+  M b(n,p); b.setRandom();
+  M c(m,p); c.setOnes();
+
+  M r = c;
+
+  // check the parallel product is correct
+  #ifdef EIGEN_HAS_OPENMP
+  int procs = omp_get_max_threads();
+  if(procs>1)
+  {
+    #ifdef HAVE_BLAS
+    blas_gemm(a,b,r);
+    #else
+    omp_set_num_threads(1);
+    r.noalias() += a * b;
+    omp_set_num_threads(procs);
+    #endif
+    c.noalias() += a * b;
+    if(!r.isApprox(c)) std::cerr << "Warning, your parallel product is crap!\n\n";
+  }
+  #endif
+
+  #ifdef HAVE_BLAS
+  BenchTimer tblas;
+  BENCH(tblas, tries, rep, blas_gemm(a,b,c));
+  std::cout << "blas  cpu         " << tblas.best(CPU_TIMER)/rep  << "s  \t" << (double(m)*n*p*rep*2/tblas.best(CPU_TIMER))*1e-9  <<  " GFLOPS \t(" << tblas.total(CPU_TIMER)  << "s)\n";
+  std::cout << "blas  real        " << tblas.best(REAL_TIMER)/rep << "s  \t" << (double(m)*n*p*rep*2/tblas.best(REAL_TIMER))*1e-9 <<  " GFLOPS \t(" << tblas.total(REAL_TIMER) << "s)\n";
+  #endif
+
+  BenchTimer tmt;
+  BENCH(tmt, tries, rep, gemm(a,b,c));
+  std::cout << "eigen cpu         " << tmt.best(CPU_TIMER)/rep  << "s  \t" << (double(m)*n*p*rep*2/tmt.best(CPU_TIMER))*1e-9  <<  " GFLOPS \t(" << tmt.total(CPU_TIMER)  << "s)\n";
+  std::cout << "eigen real        " << tmt.best(REAL_TIMER)/rep << "s  \t" << (double(m)*n*p*rep*2/tmt.best(REAL_TIMER))*1e-9 <<  " GFLOPS \t(" << tmt.total(REAL_TIMER) << "s)\n";
+
+  #ifdef EIGEN_HAS_OPENMP
+  if(procs>1)
+  {
+    BenchTimer tmono;
+    omp_set_num_threads(1);
+    BENCH(tmono, tries, rep, gemm(a,b,c));
+    std::cout << "eigen mono cpu    " << tmono.best(CPU_TIMER)/rep  << "s  \t" << (double(m)*n*p*rep*2/tmono.best(CPU_TIMER))*1e-9  <<  " GFLOPS \t(" << tmono.total(CPU_TIMER)  << "s)\n";
+    std::cout << "eigen mono real   " << tmono.best(REAL_TIMER)/rep << "s  \t" << (double(m)*n*p*rep*2/tmono.best(REAL_TIMER))*1e-9 <<  " GFLOPS \t(" << tmono.total(REAL_TIMER) << "s)\n";
+    std::cout << "mt speed up x" << tmono.best(CPU_TIMER) / tmt.best(REAL_TIMER)  << " => " << (100.0*tmono.best(CPU_TIMER) / tmt.best(REAL_TIMER))/procs << "%\n";
+  }
+  #endif
+
+  return 0;
+}
+