Grid/lib/cartesian/Cartesian_full.h

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

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

    Source file: ./lib/cartesian/Cartesian_full.h

    Copyright (C) 2015

Author: Peter Boyle <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_CARTESIAN_FULL_H
#define GRID_CARTESIAN_FULL_H

namespace Grid{
    
/////////////////////////////////////////////////////////////////////////////////////////
// Grid Support.
/////////////////////////////////////////////////////////////////////////////////////////


class GridCartesian: public GridBase {

public:
    int dummy;
    virtual int  CheckerBoardFromOindexTable (int Oindex) {
      return 0;
    }
    virtual int  CheckerBoardFromOindex (int Oindex)
    {
      return 0;
    }
    virtual int CheckerBoarded(int dim){
      return 0;
    }
    virtual int CheckerBoard(const std::vector<int> &site){
        return 0;
    }
    virtual int CheckerBoardDestination(int cb,int shift,int dim){
        return 0;
    }
    virtual int CheckerBoardShiftForCB(int source_cb,int dim,int shift, int ocb){
      return shift;
    }
    virtual int CheckerBoardShift(int source_cb,int dim,int shift, int osite){
      return shift;
    }
    /////////////////////////////////////////////////////////////////////////
    // Constructor takes a parent grid and possibly subdivides communicator.
    /////////////////////////////////////////////////////////////////////////
    GridCartesian(const std::vector<int> &dimensions,
		  const std::vector<int> &simd_layout,
		  const std::vector<int> &processor_grid,
		  const GridCartesian &parent) : GridBase(processor_grid,parent,dummy)
    {
      Init(dimensions,simd_layout,processor_grid);
    }
    GridCartesian(const std::vector<int> &dimensions,
		  const std::vector<int> &simd_layout,
		  const std::vector<int> &processor_grid,
		  const GridCartesian &parent,int &split_rank) : GridBase(processor_grid,parent,split_rank)
    {
      Init(dimensions,simd_layout,processor_grid);
    }
    /////////////////////////////////////////////////////////////////////////
    // Construct from comm world
    /////////////////////////////////////////////////////////////////////////
    GridCartesian(const std::vector<int> &dimensions,
		  const std::vector<int> &simd_layout,
		  const std::vector<int> &processor_grid) : GridBase(processor_grid)
    {
      Init(dimensions,simd_layout,processor_grid);
    }

    virtual ~GridCartesian() = default;

    void Init(const std::vector<int> &dimensions,
	      const std::vector<int> &simd_layout,
	      const std::vector<int> &processor_grid)
    {
      ///////////////////////
      // Grid information
      ///////////////////////
      _ndimension = dimensions.size();

      _fdimensions.resize(_ndimension);
      _gdimensions.resize(_ndimension);
      _ldimensions.resize(_ndimension);
      _rdimensions.resize(_ndimension);
      _simd_layout.resize(_ndimension);
      _lstart.resize(_ndimension);
      _lend.resize(_ndimension);

      _ostride.resize(_ndimension);
      _istride.resize(_ndimension);

      _fsites = _gsites = _osites = _isites = 1;

      for (int d = 0; d < _ndimension; d++)
      {
        _fdimensions[d] = dimensions[d];   // Global dimensions
        _gdimensions[d] = _fdimensions[d]; // Global dimensions
        _simd_layout[d] = simd_layout[d];
        _fsites = _fsites * _fdimensions[d];
        _gsites = _gsites * _gdimensions[d];

        // Use a reduced simd grid
        _ldimensions[d] = _gdimensions[d] / _processors[d]; //local dimensions
        assert(_ldimensions[d] * _processors[d] == _gdimensions[d]);

        _rdimensions[d] = _ldimensions[d] / _simd_layout[d]; //overdecomposition
        assert(_rdimensions[d] * _simd_layout[d] == _ldimensions[d]);

        _lstart[d] = _processor_coor[d] * _ldimensions[d];
        _lend[d] = _processor_coor[d] * _ldimensions[d] + _ldimensions[d] - 1;
        _osites *= _rdimensions[d];
        _isites *= _simd_layout[d];

        // Addressing support
        if (d == 0)
        {
          _ostride[d] = 1;
          _istride[d] = 1;
        }
        else
        {
          _ostride[d] = _ostride[d - 1] * _rdimensions[d - 1];
          _istride[d] = _istride[d - 1] * _simd_layout[d - 1];
        }
      }

      ///////////////////////
      // subplane information
      ///////////////////////
      _slice_block.resize(_ndimension);
      _slice_stride.resize(_ndimension);
      _slice_nblock.resize(_ndimension);

      int block = 1;
      int nblock = 1;
      for (int d = 0; d < _ndimension; d++)
        nblock *= _rdimensions[d];

      for (int d = 0; d < _ndimension; d++)
      {
        nblock /= _rdimensions[d];
        _slice_block[d] = block;
        _slice_stride[d] = _ostride[d] * _rdimensions[d];
        _slice_nblock[d] = nblock;
        block = block * _rdimensions[d];
      }
    };
};
}
#endif