Solv_AMG.h

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#ifndef Solv_AMG_included
#define Solv_AMG_included
 
#include <SolveurSys.h>
#include <Solv_Petsc.h>
#include <Perf_counters.h>
#include <EChaine.h>
 
/*! @brief AMD solver wrapper to switch to the more robust/performant AMG preconditioner on CPU/GPU Nvidia/GPU AMD
 *  and have datafile unicity, as changing solver/preconditioner for different architecture is painful
 */
class Solv_AMG : public SolveurSys_base
{
  Declare_instanciable(Solv_AMG);
public :
  virtual int solveur_direct() const override { return 0; };
  virtual int resoudre_systeme(const Matrice_Base& mat, const DoubleVect& b, DoubleVect& x) override;
  virtual int resoudre_systeme(const Matrice_Base& mat, const DoubleVect& b, DoubleVect& x, int niter_max) override
  {
    statistics().end_count(STD_COUNTERS::system_solver,-1,0);
    int res = solveur_.resoudre_systeme(mat, b, x);
    statistics().begin_count(STD_COUNTERS::system_solver,statistics().get_last_opened_counter_level()+1);
    return res;
  };
private :
  void create_amg();
  void create_block_amg(int,Nom);
  SolveurSys solveur_;
  Nom library_="", solver_="", options_="";
  double rtol_=-1, atol_=-1, st_=-1;
  bool impr_ = false;
  bool petsc_cg_issue_ = false;
};
 
#endif