Grid/lib/qcd/action/fermion/WilsonFermion5D.h

    /*************************************************************************************

    Grid physics library, www.github.com/paboyle/Grid 

    Source file: ./lib/qcd/action/fermion/WilsonFermion5D.h

    Copyright (C) 2015

Author: Peter Boyle <pabobyle@ph.ed.ac.uk>
Author: Peter Boyle <paboyle@ph.ed.ac.uk>
Author: paboyle <paboyle@ph.ed.ac.uk>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License along
    with this program; if not, write to the Free Software Foundation, Inc.,
    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

    See the full license in the file "LICENSE" in the top level distribution directory
    *************************************************************************************/
    /*  END LEGAL */
#ifndef  GRID_QCD_WILSON_FERMION_5D_H
#define  GRID_QCD_WILSON_FERMION_5D_H

#include <Grid/Stat.h>

namespace Grid {

  namespace QCD {

    ////////////////////////////////////////////////////////////////////////////////
    // This is the 4d red black case appropriate to support
    //
    // parity = (x+y+z+t)|2;
    // generalised five dim fermions like mobius, zolotarev etc..	
    //
    // i.e. even even contains fifth dim hopping term.
    //
    // [DIFFERS from original CPS red black implementation parity = (x+y+z+t+s)|2 ]
    ////////////////////////////////////////////////////////////////////////////////

    class WilsonFermion5DStatic { 
    public:
      // S-direction is INNERMOST and takes no part in the parity.
      static const std::vector<int> directions;
      static const std::vector<int> displacements;
      const int npoint = 8;
    };

    template<class Impl>
    class WilsonFermion5D : public WilsonKernels<Impl>, public WilsonFermion5DStatic
    {
    public:
     INHERIT_IMPL_TYPES(Impl);
     typedef WilsonKernels<Impl> Kernels;
     PmuStat stat;

     void Report(void);
     void ZeroCounters(void);
     double DhopCalls;
     double DhopCommTime;
     double DhopComputeTime;

     double DerivCalls;
     double DerivCommTime;
     double DerivComputeTime;
     double DerivDhopComputeTime;

      ///////////////////////////////////////////////////////////////
      // Implement the abstract base
      ///////////////////////////////////////////////////////////////
      GridBase *GaugeGrid(void)              { return _FourDimGrid ;}
      GridBase *GaugeRedBlackGrid(void)      { return _FourDimRedBlackGrid ;}
      GridBase *FermionGrid(void)            { return _FiveDimGrid;}
      GridBase *FermionRedBlackGrid(void)    { return _FiveDimRedBlackGrid;}

      // full checkerboard operations; leave unimplemented as abstract for now
      virtual RealD  M    (const FermionField &in, FermionField &out){assert(0); return 0.0;};
      virtual RealD  Mdag (const FermionField &in, FermionField &out){assert(0); return 0.0;};

      // half checkerboard operations; leave unimplemented as abstract for now
      virtual void   Meooe       (const FermionField &in, FermionField &out){assert(0);};
      virtual void   Mooee       (const FermionField &in, FermionField &out){assert(0);};
      virtual void   MooeeInv    (const FermionField &in, FermionField &out){assert(0);};

      virtual void   MeooeDag    (const FermionField &in, FermionField &out){assert(0);};
      virtual void   MooeeDag    (const FermionField &in, FermionField &out){assert(0);};
      virtual void   MooeeInvDag (const FermionField &in, FermionField &out){assert(0);};
      virtual void   Mdir   (const FermionField &in, FermionField &out,int dir,int disp){assert(0);};   // case by case Wilson, Clover, Cayley, ContFrac, PartFrac

      // These can be overridden by fancy 5d chiral action
      virtual void DhopDeriv  (GaugeField &mat,const FermionField &U,const FermionField &V,int dag);
      virtual void DhopDerivEO(GaugeField &mat,const FermionField &U,const FermionField &V,int dag);
      virtual void DhopDerivOE(GaugeField &mat,const FermionField &U,const FermionField &V,int dag);

      // Implement hopping term non-hermitian hopping term; half cb or both
      // Implement s-diagonal DW
      void DW    (const FermionField &in, FermionField &out,int dag);
      void Dhop  (const FermionField &in, FermionField &out,int dag);
      void DhopOE(const FermionField &in, FermionField &out,int dag);
      void DhopEO(const FermionField &in, FermionField &out,int dag);

      // add a DhopComm
      // -- suboptimal interface will presently trigger multiple comms.
      void DhopDir(const FermionField &in, FermionField &out,int dir,int disp);

      ///////////////////////////////////////////////////////////////
      // New methods added 
      ///////////////////////////////////////////////////////////////
      void DerivInternal(StencilImpl & st,
			 DoubledGaugeField & U,
			 GaugeField &mat,
			 const FermionField &A,
			 const FermionField &B,
			 int dag);

      void DhopInternal(StencilImpl & st,
			LebesgueOrder &lo,
			DoubledGaugeField &U,
			const FermionField &in, 
			FermionField &out,
			int dag);

      // Constructors
      WilsonFermion5D(GaugeField &_Umu,
		      GridCartesian         &FiveDimGrid,
		      GridRedBlackCartesian &FiveDimRedBlackGrid,
		      GridCartesian         &FourDimGrid,
		      GridRedBlackCartesian &FourDimRedBlackGrid,
		      double _M5,const ImplParams &p= ImplParams());

      // Constructors
      /*
      WilsonFermion5D(int simd, 
		      GaugeField &_Umu,
		      GridCartesian         &FiveDimGrid,
		      GridRedBlackCartesian &FiveDimRedBlackGrid,
		      GridCartesian         &FourDimGrid,
		      double _M5,const ImplParams &p= ImplParams());
      */

      // DoubleStore
      void ImportGauge(const GaugeField &_Umu);

      ///////////////////////////////////////////////////////////////
      // Data members require to support the functionality
      ///////////////////////////////////////////////////////////////
    public:

      // Add these to the support from Wilson
      GridBase *_FourDimGrid;
      GridBase *_FourDimRedBlackGrid;
      GridBase *_FiveDimGrid;
      GridBase *_FiveDimRedBlackGrid;

      double                        M5;
      int Ls;

      //Defines the stencils for even and odd
      StencilImpl Stencil; 
      StencilImpl StencilEven; 
      StencilImpl StencilOdd; 

      // Copy of the gauge field , with even and odd subsets
      DoubledGaugeField Umu;
      DoubledGaugeField UmuEven;
      DoubledGaugeField UmuOdd;

      LebesgueOrder Lebesgue;
      LebesgueOrder LebesgueEvenOdd;

      // Comms buffer
      std::vector<SiteHalfSpinor,alignedAllocator<SiteHalfSpinor> >  comm_buf;
      
    };
  }
}

#endif