src/gromacs/nbnxm/clusterdistancekerneltype.h

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
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   4  * Copyright (c) 2019, by the GROMACS development team, led by
   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
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  35
  36 /*! \internal \file
  37  *
  38  * \brief
  39  * Declares the ClusterDistanceKernelType enum
  40  *
  41  * \author Berk Hess <hess@kth.se>
  42  * \ingroup module_nbnxm
  43  */
  44
  45 #ifndef GMX_NBNXM_CLUSTERDISTANCEKERNELTYPE_H
  46 #define GMX_NBNXM_CLUSTERDISTANCEKERNELTYPE_H
  47
  48 #include "gromacs/nbnxm/atomdata.h"
  49 #include "gromacs/simd/simd.h"
  50 #include "gromacs/utility/gmxassert.h"
  51
  52 #include "pairlistparams.h"
  53
  54 //! The types of kernel for calculating the distance between pairs of atom clusters
  55 enum class ClusterDistanceKernelType : int
  56 {
  57     CpuPlainC,    //!< Plain-C for CPU list
  58     CpuSimd_4xM,  //!< SIMD for CPU list for j-cluster size matching the SIMD width
  59     CpuSimd_2xMM, //!< SIMD for CPU list for j-cluster size matching half the SIMD width
  60     Gpu           //!< For GPU list, can be either plain-C or SIMD
  61 };
  62
  63 //! Return the cluster distance kernel type given the pairlist type and atomdata
  64 static inline ClusterDistanceKernelType
  65 getClusterDistanceKernelType(const PairlistType      pairlistType,
  66                              const nbnxn_atomdata_t &atomdata)
  67 {
  68     if (pairlistType == PairlistType::HierarchicalNxN)
  69     {
  70         return ClusterDistanceKernelType::Gpu;
  71     }
  72     else if (atomdata.XFormat == nbatXYZ)
  73     {
  74         return ClusterDistanceKernelType::CpuPlainC;
  75     }
  76     else if (pairlistType == PairlistType::Simple4x2)
  77     {
  78 #if GMX_SIMD && GMX_SIMD_REAL_WIDTH == 2
  79         return ClusterDistanceKernelType::CpuSimd_4xM;
  80 #else
  81         GMX_RELEASE_ASSERT(false, "Expect 2-wide SIMD with 4x2 list and nbat SIMD layout");
  82 #endif
  83     }
  84     else if (pairlistType == PairlistType::Simple4x4)
  85     {
  86 #if GMX_SIMD && GMX_SIMD_REAL_WIDTH == 4
  87         return ClusterDistanceKernelType::CpuSimd_4xM;
  88 #elif GMX_SIMD && GMX_SIMD_REAL_WIDTH == 8
  89         return ClusterDistanceKernelType::CpuSimd_2xMM;
  90 #else
  91         GMX_RELEASE_ASSERT(false, "Expect 4-wide or 8-wide SIMD with 4x4 list and nbat SIMD layout");
  92 #endif
  93     }
  94     else
  95     {
  96         GMX_ASSERT(pairlistType == PairlistType::Simple4x8, "Unhandled pairlist type");
  97 #if GMX_SIMD && GMX_SIMD_REAL_WIDTH == 8
  98         return ClusterDistanceKernelType::CpuSimd_4xM;
  99 #elif GMX_SIMD && GMX_SIMD_REAL_WIDTH == 16
 100         return ClusterDistanceKernelType::CpuSimd_2xMM;
 101 #else
 102         GMX_RELEASE_ASSERT(false, "Expect 8-wide or 16-wide SIMD with 4x4 list and nbat SIMD layout");
 103 #endif
 104     }
 105
 106     GMX_RELEASE_ASSERT(false, "We should have returned before getting here");
 107     return ClusterDistanceKernelType::CpuPlainC;
 108 }
 109
 110 #endif