src/gromacs/nbnxm/pairlist_simd_2xmm.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,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with GROMACS; if not, see
  21  * http://www.gnu.org/licenses, or write to the Free Software Foundation,
  22  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
  23  *
  24  * If you want to redistribute modifications to GROMACS, please
  25  * consider that scientific software is very special. Version
  26  * control is crucial - bugs must be traceable. We will be happy to
  27  * consider code for inclusion in the official distribution, but
  28  * derived work must not be called official GROMACS. Details are found
  29  * in the README & COPYING files - if they are missing, get the
  30  * official version at http://www.gromacs.org.
  31  *
  32  * To help us fund GROMACS development, we humbly ask that you cite
  33  * the research papers on the package. Check out http://www.gromacs.org.
  34  */
  35
  36 /* Stride of the packed x coordinate array */
  37 static constexpr int c_xStride2xNN = c_nbnxnCpuIClusterSize;
  38
  39 /* Copies PBC shifted i-cell packed atom coordinates to working array */
  40 static inline void
  41 icell_set_x_simd_2xnn(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::Simd2xNN>(ci);
  50
  51     store(x_ci_simd + 0*GMX_SIMD_REAL_WIDTH, loadU1DualHsimd(x + ia + 0*c_xStride2xNN + 0) + SimdReal(shx) );
  52     store(x_ci_simd + 1*GMX_SIMD_REAL_WIDTH, loadU1DualHsimd(x + ia + 1*c_xStride2xNN + 0) + SimdReal(shy) );
  53     store(x_ci_simd + 2*GMX_SIMD_REAL_WIDTH, loadU1DualHsimd(x + ia + 2*c_xStride2xNN + 0) + SimdReal(shz) );
  54     store(x_ci_simd + 3*GMX_SIMD_REAL_WIDTH, loadU1DualHsimd(x + ia + 0*c_xStride2xNN + 2) + SimdReal(shx) );
  55     store(x_ci_simd + 4*GMX_SIMD_REAL_WIDTH, loadU1DualHsimd(x + ia + 1*c_xStride2xNN + 2) + SimdReal(shy) );
  56     store(x_ci_simd + 5*GMX_SIMD_REAL_WIDTH, loadU1DualHsimd(x + ia + 2*c_xStride2xNN + 2) + SimdReal(shz) );
  57 }
  58
  59 /* SIMD code for checking and adding cluster-pairs to the list using coordinates in packed format.
  60  *
  61  * Checks bouding box distances and possibly atom pair distances.
  62  * This is an accelerated version of make_cluster_list_simple.
  63  *
  64  * \param[in]     jGrid               The j-grid
  65  * \param[in,out] nbl                 The pair-list to store the cluster pairs in
  66  * \param[in]     icluster            The index of the i-cluster
  67  * \param[in]     firstCell           The first cluster in the j-range, using i-cluster size indexing
  68  * \param[in]     lastCell            The last cluster in the j-range, using i-cluster size indexing
  69  * \param[in]     excludeSubDiagonal  Exclude atom pairs with i-index > j-index
  70  * \param[in]     x_j                 Coordinates for the j-atom, in SIMD packed format
  71  * \param[in]     rlist2              The squared list cut-off
  72  * \param[in]     rbb2                The squared cut-off for putting cluster-pairs in the list based on bounding box distance only
  73  * \param[in,out] numDistanceChecks   The number of distance checks performed
  74  */
  75 static inline void
  76 makeClusterListSimd2xnn(const Grid               &jGrid,
  77                         NbnxnPairlistCpu *        nbl,
  78                         int                       icluster,
  79                         int                       firstCell,
  80                         int                       lastCell,
  81                         bool                      excludeSubDiagonal,
  82                         const real * gmx_restrict x_j,
  83                         real                      rlist2,
  84                         float                     rbb2,
  85                         int * gmx_restrict        numDistanceChecks)
  86 {
  87     using namespace gmx;
  88     const real * gmx_restrict           x_ci_simd = nbl->work->iClusterData.xSimd.data();
  89     const nbnxn_bb_t * gmx_restrict     bb_ci     = nbl->work->iClusterData.bb.data();
  90
  91     SimdReal                            jx_S, jy_S, jz_S;
  92
  93     SimdReal                            dx_S0, dy_S0, dz_S0;
  94     SimdReal                            dx_S2, dy_S2, dz_S2;
  95
  96     SimdReal                            rsq_S0;
  97     SimdReal                            rsq_S2;
  98
  99     SimdBool                            wco_S0;
 100     SimdBool                            wco_S2;
 101     SimdBool                            wco_any_S;
 102
 103     SimdReal                            rc2_S;
 104
 105     gmx_bool                            InRange;
 106     float                               d2;
 107     int                                 xind_f, xind_l;
 108
 109     int jclusterFirst = cjFromCi<NbnxnLayout::Simd2xNN, 0>(firstCell);
 110     int jclusterLast  = cjFromCi<NbnxnLayout::Simd2xNN, 1>(lastCell);
 111     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");
 112
 113     rc2_S   = SimdReal(rlist2);
 114
 115     InRange = FALSE;
 116     while (!InRange && jclusterFirst <= jclusterLast)
 117     {
 118 #if NBNXN_SEARCH_BB_SIMD4
 119         d2 = subc_bb_dist2_simd4(0, bb_ci, jclusterFirst, jGrid.jBoundingBoxes());
 120 #else
 121         d2 = subc_bb_dist2(0, bb_ci, jclusterFirst, jGrid.jBoundingBoxes());
 122 #endif
 123         *numDistanceChecks += 2;
 124
 125         /* Check if the distance is within the distance where
 126          * we use only the bounding box distance rbb,
 127          * or within the cut-off and there is at least one atom pair
 128          * within the cut-off.
 129          */
 130         if (d2 < rbb2)
 131         {
 132             InRange = TRUE;
 133         }
 134         else if (d2 < rlist2)
 135         {
 136             xind_f  = xIndexFromCj<NbnxnLayout::Simd2xNN>(cjFromCi<NbnxnLayout::Simd2xNN, 0>(jGrid.cellOffset()) + jclusterFirst);
 137
 138             jx_S  = loadDuplicateHsimd(x_j + xind_f + 0*c_xStride2xNN);
 139             jy_S  = loadDuplicateHsimd(x_j + xind_f + 1*c_xStride2xNN);
 140             jz_S  = loadDuplicateHsimd(x_j + xind_f + 2*c_xStride2xNN);
 141
 142             /* Calculate distance */
 143             dx_S0            = load<SimdReal>(x_ci_simd + 0*GMX_SIMD_REAL_WIDTH) - jx_S;
 144             dy_S0            = load<SimdReal>(x_ci_simd + 1*GMX_SIMD_REAL_WIDTH) - jy_S;
 145             dz_S0            = load<SimdReal>(x_ci_simd + 2*GMX_SIMD_REAL_WIDTH) - jz_S;
 146             dx_S2            = load<SimdReal>(x_ci_simd + 3*GMX_SIMD_REAL_WIDTH) - jx_S;
 147             dy_S2            = load<SimdReal>(x_ci_simd + 4*GMX_SIMD_REAL_WIDTH) - jy_S;
 148             dz_S2            = load<SimdReal>(x_ci_simd + 5*GMX_SIMD_REAL_WIDTH) - jz_S;
 149
 150             /* rsq = dx*dx+dy*dy+dz*dz */
 151             rsq_S0           = norm2(dx_S0, dy_S0, dz_S0);
 152             rsq_S2           = norm2(dx_S2, dy_S2, dz_S2);
 153
 154             wco_S0           = (rsq_S0 < rc2_S);
 155             wco_S2           = (rsq_S2 < rc2_S);
 156
 157             wco_any_S        = wco_S0 || wco_S2;
 158
 159             InRange          = anyTrue(wco_any_S);
 160
 161             *numDistanceChecks += 2*GMX_SIMD_REAL_WIDTH;
 162         }
 163         if (!InRange)
 164         {
 165             jclusterFirst++;
 166         }
 167     }
 168     if (!InRange)
 169     {
 170         return;
 171     }
 172
 173     InRange = FALSE;
 174     while (!InRange && jclusterLast > jclusterFirst)
 175     {
 176 #if NBNXN_SEARCH_BB_SIMD4
 177         d2 = subc_bb_dist2_simd4(0, bb_ci, jclusterLast, jGrid.jBoundingBoxes());
 178 #else
 179         d2 = subc_bb_dist2(0, bb_ci, jclusterLast, jGrid.jBoundingBoxes());
 180 #endif
 181         *numDistanceChecks += 2;
 182
 183         /* Check if the distance is within the distance where
 184          * we use only the bounding box distance rbb,
 185          * or within the cut-off and there is at least one atom pair
 186          * within the cut-off.
 187          */
 188         if (d2 < rbb2)
 189         {
 190             InRange = TRUE;
 191         }
 192         else if (d2 < rlist2)
 193         {
 194             xind_l  = xIndexFromCj<NbnxnLayout::Simd2xNN>(cjFromCi<NbnxnLayout::Simd2xNN, 0>(jGrid.cellOffset()) + jclusterLast);
 195
 196             jx_S  = loadDuplicateHsimd(x_j + xind_l + 0*c_xStride2xNN);
 197             jy_S  = loadDuplicateHsimd(x_j + xind_l + 1*c_xStride2xNN);
 198             jz_S  = loadDuplicateHsimd(x_j + xind_l + 2*c_xStride2xNN);
 199
 200             /* Calculate distance */
 201             dx_S0            = load<SimdReal>(x_ci_simd + 0*GMX_SIMD_REAL_WIDTH) - jx_S;
 202             dy_S0            = load<SimdReal>(x_ci_simd + 1*GMX_SIMD_REAL_WIDTH) - jy_S;
 203             dz_S0            = load<SimdReal>(x_ci_simd + 2*GMX_SIMD_REAL_WIDTH) - jz_S;
 204             dx_S2            = load<SimdReal>(x_ci_simd + 3*GMX_SIMD_REAL_WIDTH) - jx_S;
 205             dy_S2            = load<SimdReal>(x_ci_simd + 4*GMX_SIMD_REAL_WIDTH) - jy_S;
 206             dz_S2            = load<SimdReal>(x_ci_simd + 5*GMX_SIMD_REAL_WIDTH) - jz_S;
 207
 208             /* rsq = dx*dx+dy*dy+dz*dz */
 209             rsq_S0           = norm2(dx_S0, dy_S0, dz_S0);
 210             rsq_S2           = norm2(dx_S2, dy_S2, dz_S2);
 211
 212             wco_S0           = (rsq_S0 < rc2_S);
 213             wco_S2           = (rsq_S2 < rc2_S);
 214
 215             wco_any_S        = wco_S0 || wco_S2;
 216
 217             InRange          = anyTrue(wco_any_S);
 218
 219             *numDistanceChecks += 2*GMX_SIMD_REAL_WIDTH;
 220         }
 221         if (!InRange)
 222         {
 223             jclusterLast--;
 224         }
 225     }
 226
 227     if (jclusterFirst <= jclusterLast)
 228     {
 229         for (int jcluster = jclusterFirst; jcluster <= jclusterLast; jcluster++)
 230         {
 231             /* Store cj and the interaction mask */
 232             nbnxn_cj_t cjEntry;
 233             cjEntry.cj   = cjFromCi<NbnxnLayout::Simd2xNN, 0>(jGrid.cellOffset()) + jcluster;
 234             cjEntry.excl = get_imask_simd_2xnn(excludeSubDiagonal, icluster, jcluster);
 235             nbl->cj.push_back(cjEntry);
 236         }
 237         /* Increase the closing index in the i list */
 238         nbl->ci.back().cj_ind_end = nbl->cj.size();
 239     }
 240 }