scalarProd_cpu.cpp

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////////////////////////////////////////////////////////////////////////////
// Calculate scalar products of VectorN vectors of ElementN elements on CPU.
// Straight accumulation in double precision.
////////////////////////////////////////////////////////////////////////////
extern "C" void scalarProdCPU(float *h_C, float *h_A, float *h_B, int vectorN,
                              int elementN) {
  for (int vec = 0; vec < vectorN; vec++) {
    int vectorBase = elementN * vec;
    int vectorEnd = vectorBase + elementN;

    double sum = 0;

    for (int pos = vectorBase; pos < vectorEnd; pos++)
      sum += h_A[pos] * h_B[pos];

    h_C[vec] = (float)sum;
  }
}