src/gromacs/nbnxm/pairlist_simd_4xm.h

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2012,2013,2014,2015,2016,2017,2018,2019, by the GROMACS development team, led by
   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
   6  * and including many others, as listed in the AUTHORS file in the
   7  * top-level source directory and at http://www.gromacs.org.
   8  *
   9  * GROMACS is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1
  12  * of the License, or (at your option) any later version.
  13  *
  14  * GROMACS is distributed in the hope that it will be useful,
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  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
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  34  */
  35
  36 /* Stride of the packed x coordinate array */
  37 static constexpr int c_xStride4xN = (GMX_SIMD_REAL_WIDTH > c_nbnxnCpuIClusterSize ? GMX_SIMD_REAL_WIDTH : c_nbnxnCpuIClusterSize);
  38
  39 /* Copies PBC shifted i-cell packed atom coordinates to working array */
  40 static inline void
  41 icell_set_x_simd_4xn(int ci,
  42                      real shx, real shy, real shz,
  43                      int gmx_unused stride, const real *x,
  44                      NbnxnPairlistCpuWork *work)
  45 {
  46     int    ia;
  47     real  *x_ci_simd = work->iClusterData.xSimd.data();
  48
  49     ia = xIndexFromCi<NbnxnLayout::Simd4xN>(ci);
  50
  51     store(x_ci_simd +  0*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0*c_xStride4xN    ] + shx) );
  52     store(x_ci_simd +  1*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1*c_xStride4xN    ] + shy) );
  53     store(x_ci_simd +  2*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2*c_xStride4xN    ] + shz) );
  54     store(x_ci_simd +  3*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0*c_xStride4xN + 1] + shx) );
  55     store(x_ci_simd +  4*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1*c_xStride4xN + 1] + shy) );
  56     store(x_ci_simd +  5*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2*c_xStride4xN + 1] + shz) );
  57     store(x_ci_simd +  6*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0*c_xStride4xN + 2] + shx) );
  58     store(x_ci_simd +  7*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1*c_xStride4xN + 2] + shy) );
  59     store(x_ci_simd +  8*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2*c_xStride4xN + 2] + shz) );
  60     store(x_ci_simd +  9*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0*c_xStride4xN + 3] + shx) );
  61     store(x_ci_simd + 10*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1*c_xStride4xN + 3] + shy) );
  62     store(x_ci_simd + 11*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2*c_xStride4xN + 3] + shz) );
  63 }
  64
  65 /* SIMD code for checking and adding cluster-pairs to the list using coordinates in packed format.
  66  *
  67  * Checks bouding box distances and possibly atom pair distances.
  68  * This is an accelerated version of make_cluster_list_simple.
  69  *
  70  * \param[in]     jGrid               The j-grid
  71  * \param[in,out] nbl                 The pair-list to store the cluster pairs in
  72  * \param[in]     icluster            The index of the i-cluster
  73  * \param[in]     firstCell           The first cluster in the j-range, using i-cluster size indexing
  74  * \param[in]     lastCell            The last cluster in the j-range, using i-cluster size indexing
  75  * \param[in]     excludeSubDiagonal  Exclude atom pairs with i-index > j-index
  76  * \param[in]     x_j                 Coordinates for the j-atom, in SIMD packed format
  77  * \param[in]     rlist2              The squared list cut-off
  78  * \param[in]     rbb2                The squared cut-off for putting cluster-pairs in the list based on bounding box distance only
  79  * \param[in,out] numDistanceChecks   The number of distance checks performed
  80  */
  81 static inline void
  82 makeClusterListSimd4xn(const Grid               &jGrid,
  83                        NbnxnPairlistCpu *        nbl,
  84                        int                       icluster,
  85                        int                       firstCell,
  86                        int                       lastCell,
  87                        bool                      excludeSubDiagonal,
  88                        const real * gmx_restrict x_j,
  89                        real                      rlist2,
  90                        float                     rbb2,
  91                        int * gmx_restrict        numDistanceChecks)
  92 {
  93     using namespace gmx;
  94     const real * gmx_restrict          x_ci_simd = nbl->work->iClusterData.xSimd.data();
  95     const nbnxn_bb_t * gmx_restrict    bb_ci     = nbl->work->iClusterData.bb.data();
  96
  97     SimdReal                           jx_S, jy_S, jz_S;
  98
  99     SimdReal                           dx_S0, dy_S0, dz_S0;
 100     SimdReal                           dx_S1, dy_S1, dz_S1;
 101     SimdReal                           dx_S2, dy_S2, dz_S2;
 102     SimdReal                           dx_S3, dy_S3, dz_S3;
 103
 104     SimdReal                           rsq_S0;
 105     SimdReal                           rsq_S1;
 106     SimdReal                           rsq_S2;
 107     SimdReal                           rsq_S3;
 108
 109     SimdBool                           wco_S0;
 110     SimdBool                           wco_S1;
 111     SimdBool                           wco_S2;
 112     SimdBool                           wco_S3;
 113     SimdBool                           wco_any_S01, wco_any_S23, wco_any_S;
 114
 115     SimdReal                           rc2_S;
 116
 117     gmx_bool                           InRange;
 118     float                              d2;
 119     int                                xind_f, xind_l;
 120
 121     /* Convert the j-range from i-cluster size indexing to j-cluster indexing */
 122     int jclusterFirst = cjFromCi<NbnxnLayout::Simd4xN, 0>(firstCell);
 123     int jclusterLast  = cjFromCi<NbnxnLayout::Simd4xN, 1>(lastCell);
 124     GMX_ASSERT(jclusterLast >= jclusterFirst, "We should have a non-empty j-cluster range, since the calling code should have ensured a non-empty cell range");
 125
 126     rc2_S   = SimdReal(rlist2);
 127
 128     InRange = FALSE;
 129     while (!InRange && jclusterFirst <= jclusterLast)
 130     {
 131 #if NBNXN_SEARCH_BB_SIMD4
 132         d2 = subc_bb_dist2_simd4(0, bb_ci, jclusterFirst, jGrid.jBoundingBoxes());
 133 #else
 134         d2 = subc_bb_dist2(0, bb_ci, jclusterFirst, jGrid.jBoundingBoxes());
 135 #endif
 136         *numDistanceChecks += 2;
 137
 138         /* Check if the distance is within the distance where
 139          * we use only the bounding box distance rbb,
 140          * or within the cut-off and there is at least one atom pair
 141          * within the cut-off.
 142          */
 143         if (d2 < rbb2)
 144         {
 145             InRange = TRUE;
 146         }
 147         else if (d2 < rlist2)
 148         {
 149             xind_f  = xIndexFromCj<NbnxnLayout::Simd4xN>(cjFromCi<NbnxnLayout::Simd4xN, 0>(jGrid.cellOffset()) + jclusterFirst);
 150
 151             jx_S  = load<SimdReal>(x_j + xind_f + 0*c_xStride4xN);
 152             jy_S  = load<SimdReal>(x_j + xind_f + 1*c_xStride4xN);
 153             jz_S  = load<SimdReal>(x_j + xind_f + 2*c_xStride4xN);
 154
 155
 156             /* Calculate distance */
 157             dx_S0            = load<SimdReal>(x_ci_simd +  0*GMX_SIMD_REAL_WIDTH) - jx_S;
 158             dy_S0            = load<SimdReal>(x_ci_simd +  1*GMX_SIMD_REAL_WIDTH) - jy_S;
 159             dz_S0            = load<SimdReal>(x_ci_simd +  2*GMX_SIMD_REAL_WIDTH) - jz_S;
 160             dx_S1            = load<SimdReal>(x_ci_simd +  3*GMX_SIMD_REAL_WIDTH) - jx_S;
 161             dy_S1            = load<SimdReal>(x_ci_simd +  4*GMX_SIMD_REAL_WIDTH) - jy_S;
 162             dz_S1            = load<SimdReal>(x_ci_simd +  5*GMX_SIMD_REAL_WIDTH) - jz_S;
 163             dx_S2            = load<SimdReal>(x_ci_simd +  6*GMX_SIMD_REAL_WIDTH) - jx_S;
 164             dy_S2            = load<SimdReal>(x_ci_simd +  7*GMX_SIMD_REAL_WIDTH) - jy_S;
 165             dz_S2            = load<SimdReal>(x_ci_simd +  8*GMX_SIMD_REAL_WIDTH) - jz_S;
 166             dx_S3            = load<SimdReal>(x_ci_simd +  9*GMX_SIMD_REAL_WIDTH) - jx_S;
 167             dy_S3            = load<SimdReal>(x_ci_simd + 10*GMX_SIMD_REAL_WIDTH) - jy_S;
 168             dz_S3            = load<SimdReal>(x_ci_simd + 11*GMX_SIMD_REAL_WIDTH) - jz_S;
 169
 170             /* rsq = dx*dx+dy*dy+dz*dz */
 171             rsq_S0           = norm2(dx_S0, dy_S0, dz_S0);
 172             rsq_S1           = norm2(dx_S1, dy_S1, dz_S1);
 173             rsq_S2           = norm2(dx_S2, dy_S2, dz_S2);
 174             rsq_S3           = norm2(dx_S3, dy_S3, dz_S3);
 175
 176             wco_S0           = (rsq_S0 < rc2_S);
 177             wco_S1           = (rsq_S1 < rc2_S);
 178             wco_S2           = (rsq_S2 < rc2_S);
 179             wco_S3           = (rsq_S3 < rc2_S);
 180
 181             wco_any_S01      = wco_S0 || wco_S1;
 182             wco_any_S23      = wco_S2 || wco_S3;
 183             wco_any_S        = wco_any_S01 || wco_any_S23;
 184
 185             InRange          = anyTrue(wco_any_S);
 186
 187             *numDistanceChecks += 4*GMX_SIMD_REAL_WIDTH;
 188         }
 189         if (!InRange)
 190         {
 191             jclusterFirst++;
 192         }
 193     }
 194     if (!InRange)
 195     {
 196         return;
 197     }
 198
 199     InRange = FALSE;
 200     while (!InRange && jclusterLast > jclusterFirst)
 201     {
 202 #if NBNXN_SEARCH_BB_SIMD4
 203         d2 = subc_bb_dist2_simd4(0, bb_ci, jclusterLast, jGrid.jBoundingBoxes());
 204 #else
 205         d2 = subc_bb_dist2(0, bb_ci, jclusterLast, jGrid.jBoundingBoxes());
 206 #endif
 207         *numDistanceChecks += 2;
 208
 209         /* Check if the distance is within the distance where
 210          * we use only the bounding box distance rbb,
 211          * or within the cut-off and there is at least one atom pair
 212          * within the cut-off.
 213          */
 214         if (d2 < rbb2)
 215         {
 216             InRange = TRUE;
 217         }
 218         else if (d2 < rlist2)
 219         {
 220             xind_l  = xIndexFromCj<NbnxnLayout::Simd4xN>(cjFromCi<NbnxnLayout::Simd4xN, 0>(jGrid.cellOffset()) + jclusterLast);
 221
 222             jx_S  = load<SimdReal>(x_j +xind_l + 0*c_xStride4xN);
 223             jy_S  = load<SimdReal>(x_j +xind_l + 1*c_xStride4xN);
 224             jz_S  = load<SimdReal>(x_j +xind_l + 2*c_xStride4xN);
 225
 226             /* Calculate distance */
 227             dx_S0            = load<SimdReal>(x_ci_simd +  0*GMX_SIMD_REAL_WIDTH) - jx_S;
 228             dy_S0            = load<SimdReal>(x_ci_simd +  1*GMX_SIMD_REAL_WIDTH) - jy_S;
 229             dz_S0            = load<SimdReal>(x_ci_simd +  2*GMX_SIMD_REAL_WIDTH) - jz_S;
 230             dx_S1            = load<SimdReal>(x_ci_simd +  3*GMX_SIMD_REAL_WIDTH) - jx_S;
 231             dy_S1            = load<SimdReal>(x_ci_simd +  4*GMX_SIMD_REAL_WIDTH) - jy_S;
 232             dz_S1            = load<SimdReal>(x_ci_simd +  5*GMX_SIMD_REAL_WIDTH) - jz_S;
 233             dx_S2            = load<SimdReal>(x_ci_simd +  6*GMX_SIMD_REAL_WIDTH) - jx_S;
 234             dy_S2            = load<SimdReal>(x_ci_simd +  7*GMX_SIMD_REAL_WIDTH) - jy_S;
 235             dz_S2            = load<SimdReal>(x_ci_simd +  8*GMX_SIMD_REAL_WIDTH) - jz_S;
 236             dx_S3            = load<SimdReal>(x_ci_simd +  9*GMX_SIMD_REAL_WIDTH) - jx_S;
 237             dy_S3            = load<SimdReal>(x_ci_simd + 10*GMX_SIMD_REAL_WIDTH) - jy_S;
 238             dz_S3            = load<SimdReal>(x_ci_simd + 11*GMX_SIMD_REAL_WIDTH) - jz_S;
 239
 240             /* rsq = dx*dx+dy*dy+dz*dz */
 241             rsq_S0           = norm2(dx_S0, dy_S0, dz_S0);
 242             rsq_S1           = norm2(dx_S1, dy_S1, dz_S1);
 243             rsq_S2           = norm2(dx_S2, dy_S2, dz_S2);
 244             rsq_S3           = norm2(dx_S3, dy_S3, dz_S3);
 245
 246             wco_S0           = (rsq_S0 < rc2_S);
 247             wco_S1           = (rsq_S1 < rc2_S);
 248             wco_S2           = (rsq_S2 < rc2_S);
 249             wco_S3           = (rsq_S3 < rc2_S);
 250
 251             wco_any_S01      = wco_S0 || wco_S1;
 252             wco_any_S23      = wco_S2 || wco_S3;
 253             wco_any_S        = wco_any_S01 || wco_any_S23;
 254
 255             InRange          = anyTrue(wco_any_S);
 256
 257             *numDistanceChecks += 4*GMX_SIMD_REAL_WIDTH;
 258         }
 259         if (!InRange)
 260         {
 261             jclusterLast--;
 262         }
 263     }
 264
 265     if (jclusterFirst <= jclusterLast)
 266     {
 267         for (int jcluster = jclusterFirst; jcluster <= jclusterLast; jcluster++)
 268         {
 269             /* Store cj and the interaction mask */
 270             nbnxn_cj_t cjEntry;
 271             cjEntry.cj   = cjFromCi<NbnxnLayout::Simd4xN, 0>(jGrid.cellOffset()) + jcluster;
 272             cjEntry.excl = get_imask_simd_4xn(excludeSubDiagonal, icluster, jcluster);
 273             nbl->cj.push_back(cjEntry);
 274         }
 275         /* Increase the closing index in the i list */
 276         nbl->ci.back().cj_ind_end = nbl->cj.size();
 277     }
 278 }