1 /***************************************************************************
2                                  lj_expand.h
3                              -------------------
4                             Inderaj Bains (NVIDIA)
5 
6   Class for acceleration of the lj/expand pair style.
7 
8  __________________________________________________________________________
9     This file is part of the LAMMPS Accelerator Library (LAMMPS_AL)
10  __________________________________________________________________________
11 
12     begin                :
13     email                : ibains@nvidia.com
14  ***************************************************************************/
15 
16 #ifndef LAL_LJ_EXPAND_H
17 #define LAL_LJ_EXPAND_H
18 
19 #include "lal_base_atomic.h"
20 
21 namespace LAMMPS_AL {
22 
23 template <class numtyp, class acctyp>
24 class LJExpand : public BaseAtomic<numtyp, acctyp> {
25  public:
26   LJExpand();
27   ~LJExpand();
28 
29   /// Clear any previous data and set up for a new LAMMPS run
30   /** \param max_nbors initial number of rows in the neighbor matrix
31     * \param cell_size cutoff + skin
32     * \param gpu_split fraction of particles handled by device
33     *
34     * Returns:
35     * -  0 if successfull
36     * - -1 if fix gpu not found
37     * - -3 if there is an out of memory error
38     * - -4 if the GPU library was not compiled for GPU
39     * - -5 Double precision is not supported on card **/
40   int init(const int ntypes, double **host_cutsq, double **host_lj1,
41            double **host_lj2, double **host_lj3, double **host_lj4,
42            double **host_offset, double **host_shift, double *host_special_lj,
43            const int nlocal, const int nall, const int max_nbors,
44            const int maxspecial, const double cell_size,
45            const double gpu_split, FILE *screen);
46 
47   /// Clear all host and device data
48   /** \note This is called at the beginning of the init() routine **/
49   void clear();
50 
51   /// Returns memory usage on device per atom
52   int bytes_per_atom(const int max_nbors) const;
53 
54   /// Total host memory used by library for pair style
55   double host_memory_usage() const;
56 
57   // --------------------------- TYPE DATA --------------------------
58 
59   /// lj1.x = lj1, lj1.y = lj2, lj1.z = cutsq, lj1.w = shift
60   UCL_D_Vec<numtyp4> lj1;
61   /// lj3.x = lj3, lj3.y = lj4, lj3.z = offset
62   UCL_D_Vec<numtyp4> lj3;
63   /// Special LJ values
64   UCL_D_Vec<numtyp> sp_lj;
65 
66   /// If atom type constants fit in shared memory, use fast kernels
67   bool shared_types;
68 
69   /// Number of atom types
70   int _lj_types;
71 
72  private:
73   bool _allocated;
74   void loop(const bool _eflag, const bool _vflag);
75 };
76 
77 }
78 
79 #endif
80