WCudaMSE/Student_OMP/src/cpp/core/omp/02_pi/02_pi_entrelacer_promotionTab.cpp

   1 #include <omp.h>
   2
   3 #include <cstring>
   4
   5 #include "00_pi_tools.h"
   6 #include "OmpTools.h"
   7
   8 /*----------------------------------------------------------------------*\
   9  |*                     Declaration                                     *|
  10  \*---------------------------------------------------------------------*/
  11
  12 /*--------------------------------------*\
  13  |*             Imported                *|
  14  \*-------------------------------------*/
  15
  16
  17 /*--------------------------------------*\
  18  |*             Public                  *|
  19  \*-------------------------------------*/
  20
  21 bool isPiOMPEntrelacerPromotionTab_Ok(int n);
  22
  23 /*--------------------------------------*\
  24  |*             Private                 *|
  25  \*-------------------------------------*/
  26
  27 static double piOMPEntrelacerPromotionTab(int n);
  28
  29 /*----------------------------------------------------------------------*\
  30  |*                     Implementation                                  *|
  31  \*---------------------------------------------------------------------*/
  32
  33 /*--------------------------------------*\
  34  |*             Public                  *|
  35  \*-------------------------------------*/
  36
  37 bool isPiOMPEntrelacerPromotionTab_Ok(int n)
  38     {
  39     return isAlgoPI_OK(piOMPEntrelacerPromotionTab,  n, "Pi OMP Entrelacer promotionTab");
  40     }
  41
  42 /*--------------------------------------*\
  43  |*             Private                 *|
  44  \*-------------------------------------*/
  45
  46 /**
  47  * pattern cuda : excellent!
  48  */
  49 double piOMPEntrelacerPromotionTab(int n)
  50     {
  51     const int NB_THREAD = OmpTools::setAndGetNaturalGranularity();
  52
  53     double* tabSums = new double[NB_THREAD];
  54     memset(tabSums, 0, NB_THREAD * sizeof(double));
  55
  56     const double DX = 1.0/(double)n;
  57
  58     #pragma omp parallel
  59         {
  60         double xs;
  61         const int TID = OmpTools::getTid();
  62         int s = TID;
  63
  64         while (s < n)
  65             {
  66             xs = s * DX;
  67             tabSums[TID] += fpi(xs);
  68
  69             s += NB_THREAD;
  70             }
  71         }
  72
  73     double sum = 0;
  74     for (int i = 0; i < NB_THREAD; i++)
  75         sum += tabSums[i];
  76
  77     delete[] tabSums;
  78
  79     return sum * DX;
  80     }
  81
  82 /*----------------------------------------------------------------------*\
  83  |*                     End                                             *|
  84  \*---------------------------------------------------------------------*/
  85