Line data    Source code

       1              : #pragma once
       2              : 
       3              : #include "tarch/utils/Utils.h"
       4              : 
       5              : namespace simplemd {
       6              : namespace moleculemappings {
       7              : class ConvertForcesFloatToFixedMapping;
       8              : }
       9              : } // namespace simplemd
      10              : 
      11              : /*
      12              :  * fixed-point math for force accumulation
      13              :  * only active in debug mode, useful for verification of simulation results
      14              :  * because results do not depend on order of force summation
      15              :  * this expects forces to contain long int and converts them back into double
      16              :  */
      17              : class simplemd::moleculemappings::ConvertForcesFloatToFixedMapping {
      18              : public:
      19              :   void beginMoleculeIteration() const {}
      20              : 
      21            0 :   KOKKOS_FUNCTION void handleMolecule(simplemd::Molecule& molecule) const {
      22            0 :     DEFINE_DECIMAL_FP_LIMITS(6);
      23              : 
      24            0 :     tarch::la::Vector<MD_DIM, double> force = stepFP6 * molecule.getForce();
      25            0 :     long long fb0{(long long)(force[0])};
      26            0 :     long long fb1{(long long)(force[1])};
      27            0 :     long long fb2{(long long)(force[2])};
      28            0 :     long long& fb0r = fb0;
      29            0 :     long long& fb1r = fb1;
      30            0 :     long long& fb2r = fb2;
      31            0 :     molecule.getForce()[0] = *(double*)(&fb0r);
      32            0 :     molecule.getForce()[1] = *(double*)(&fb1r);
      33            0 :     molecule.getForce()[2] = *(double*)(&fb2r);
      34            0 :   }
      35              : 
      36              :   void endMoleculeIteration() const {}
      37              : 
      38              :   static const bool IsParallel = true;
      39              : };