src/gromacs/mdlib/nbnxn_search_simd_4xn.h

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2012,2013,2014,2015,2016,2017,2018, 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  *
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  17  * Lesser General Public License for more details.
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  34  */
  35
  36 #if GMX_SIMD_REAL_WIDTH >= NBNXN_CPU_CLUSTER_I_SIZE
  37 #define STRIDE_S  (GMX_SIMD_REAL_WIDTH)
  38 #else
  39 #define STRIDE_S  NBNXN_CPU_CLUSTER_I_SIZE
  40 #endif
  41
  42 /* Copies PBC shifted i-cell packed atom coordinates to working array */
  43 static inline void
  44 icell_set_x_simd_4xn(int ci,
  45                      real shx, real shy, real shz,
  46                      int gmx_unused stride, const real *x,
  47                      nbnxn_list_work_t *work)
  48 {
  49     int    ia;
  50     real  *x_ci_simd = work->x_ci_simd;
  51
  52     ia = xIndexFromCi<NbnxnLayout::Simd4xN>(ci);
  53
  54     store(x_ci_simd +  0*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0*STRIDE_S    ] + shx) );
  55     store(x_ci_simd +  1*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1*STRIDE_S    ] + shy) );
  56     store(x_ci_simd +  2*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2*STRIDE_S    ] + shz) );
  57     store(x_ci_simd +  3*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0*STRIDE_S + 1] + shx) );
  58     store(x_ci_simd +  4*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1*STRIDE_S + 1] + shy) );
  59     store(x_ci_simd +  5*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2*STRIDE_S + 1] + shz) );
  60     store(x_ci_simd +  6*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0*STRIDE_S + 2] + shx) );
  61     store(x_ci_simd +  7*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1*STRIDE_S + 2] + shy) );
  62     store(x_ci_simd +  8*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2*STRIDE_S + 2] + shz) );
  63     store(x_ci_simd +  9*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0*STRIDE_S + 3] + shx) );
  64     store(x_ci_simd + 10*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1*STRIDE_S + 3] + shy) );
  65     store(x_ci_simd + 11*GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2*STRIDE_S + 3] + shz) );
  66 }
  67
  68 /* SIMD code for checking and adding cluster-pairs to the list using coordinates in packed format.
  69  *
  70  * Checks bouding box distances and possibly atom pair distances.
  71  * This is an accelerated version of make_cluster_list_simple.
  72  *
  73  * \param[in]     gridj               The j-grid
  74  * \param[in,out] nbl                 The pair-list to store the cluster pairs in
  75  * \param[in]     icluster            The index of the i-cluster
  76  * \param[in]     firstCell           The first cluster in the j-range, using i-cluster size indexing
  77  * \param[in]     lastCell            The last cluster in the j-range, using i-cluster size indexing
  78  * \param[in]     excludeSubDiagonal  Exclude atom pairs with i-index > j-index
  79  * \param[in]     x_j                 Coordinates for the j-atom, in SIMD packed format
  80  * \param[in]     rlist2              The squared list cut-off
  81  * \param[in]     rbb2                The squared cut-off for putting cluster-pairs in the list based on bounding box distance only
  82  * \param[in,out] numDistanceChecks   The number of distance checks performed
  83  */
  84 static inline void
  85 makeClusterListSimd4xn(const nbnxn_grid_t *      gridj,
  86                        nbnxn_pairlist_t *        nbl,
  87                        int                       icluster,
  88                        int                       firstCell,
  89                        int                       lastCell,
  90                        bool                      excludeSubDiagonal,
  91                        const real * gmx_restrict x_j,
  92                        real                      rlist2,
  93                        float                     rbb2,
  94                        int * gmx_restrict        numDistanceChecks)
  95 {
  96     using namespace gmx;
  97     const real * gmx_restrict          x_ci_simd = nbl->work->x_ci_simd;
  98     const nbnxn_bb_t * gmx_restrict    bb_ci     = nbl->work->bb_ci;
  99
 100     SimdReal                           jx_S, jy_S, jz_S;
 101
 102     SimdReal                           dx_S0, dy_S0, dz_S0;
 103     SimdReal                           dx_S1, dy_S1, dz_S1;
 104     SimdReal                           dx_S2, dy_S2, dz_S2;
 105     SimdReal                           dx_S3, dy_S3, dz_S3;
 106
 107     SimdReal                           rsq_S0;
 108     SimdReal                           rsq_S1;
 109     SimdReal                           rsq_S2;
 110     SimdReal                           rsq_S3;
 111
 112     SimdBool                           wco_S0;
 113     SimdBool                           wco_S1;
 114     SimdBool                           wco_S2;
 115     SimdBool                           wco_S3;
 116     SimdBool                           wco_any_S01, wco_any_S23, wco_any_S;
 117
 118     SimdReal                           rc2_S;
 119
 120     gmx_bool                           InRange;
 121     float                              d2;
 122     int                                xind_f, xind_l;
 123
 124     /* Convert the j-range from i-cluster size indexing to j-cluster indexing */
 125     /* cppcheck-suppress selfAssignment . selfAssignment for width 4.*/
 126     int jclusterFirst = cjFromCi<NbnxnLayout::Simd4xN>(firstCell);
 127 #if GMX_SIMD_REAL_WIDTH >= NBNXN_CPU_CLUSTER_I_SIZE
 128     int jclusterLast  = cjFromCi<NbnxnLayout::Simd4xN>(lastCell);
 129 #else
 130     /* Set the correct last j-cluster with a j-cluster size of 2 */
 131     int jclusterLast  = cjFromCi<NbnxnLayout::Simd4xN>(lastCell + 1) - 1;
 132 #endif
 133     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");
 134
 135     rc2_S   = SimdReal(rlist2);
 136
 137     InRange = FALSE;
 138     while (!InRange && jclusterFirst <= jclusterLast)
 139     {
 140 #if NBNXN_SEARCH_BB_SIMD4
 141         d2 = subc_bb_dist2_simd4(0, bb_ci, jclusterFirst, gridj->bbj);
 142 #else
 143         d2 = subc_bb_dist2(0, bb_ci, jclusterFirst, gridj->bbj);
 144 #endif
 145         *numDistanceChecks += 2;
 146
 147         /* Check if the distance is within the distance where
 148          * we use only the bounding box distance rbb,
 149          * or within the cut-off and there is at least one atom pair
 150          * within the cut-off.
 151          */
 152         if (d2 < rbb2)
 153         {
 154             InRange = TRUE;
 155         }
 156         else if (d2 < rlist2)
 157         {
 158             xind_f  = xIndexFromCj<NbnxnLayout::Simd4xN>(cjFromCi<NbnxnLayout::Simd4xN>(gridj->cell0) + jclusterFirst);
 159
 160             jx_S  = load<SimdReal>(x_j + xind_f + 0*STRIDE_S);
 161             jy_S  = load<SimdReal>(x_j + xind_f + 1*STRIDE_S);
 162             jz_S  = load<SimdReal>(x_j + xind_f + 2*STRIDE_S);
 163
 164
 165             /* Calculate distance */
 166             dx_S0            = load<SimdReal>(x_ci_simd +  0*GMX_SIMD_REAL_WIDTH) - jx_S;
 167             dy_S0            = load<SimdReal>(x_ci_simd +  1*GMX_SIMD_REAL_WIDTH) - jy_S;
 168             dz_S0            = load<SimdReal>(x_ci_simd +  2*GMX_SIMD_REAL_WIDTH) - jz_S;
 169             dx_S1            = load<SimdReal>(x_ci_simd +  3*GMX_SIMD_REAL_WIDTH) - jx_S;
 170             dy_S1            = load<SimdReal>(x_ci_simd +  4*GMX_SIMD_REAL_WIDTH) - jy_S;
 171             dz_S1            = load<SimdReal>(x_ci_simd +  5*GMX_SIMD_REAL_WIDTH) - jz_S;
 172             dx_S2            = load<SimdReal>(x_ci_simd +  6*GMX_SIMD_REAL_WIDTH) - jx_S;
 173             dy_S2            = load<SimdReal>(x_ci_simd +  7*GMX_SIMD_REAL_WIDTH) - jy_S;
 174             dz_S2            = load<SimdReal>(x_ci_simd +  8*GMX_SIMD_REAL_WIDTH) - jz_S;
 175             dx_S3            = load<SimdReal>(x_ci_simd +  9*GMX_SIMD_REAL_WIDTH) - jx_S;
 176             dy_S3            = load<SimdReal>(x_ci_simd + 10*GMX_SIMD_REAL_WIDTH) - jy_S;
 177             dz_S3            = load<SimdReal>(x_ci_simd + 11*GMX_SIMD_REAL_WIDTH) - jz_S;
 178
 179             /* rsq = dx*dx+dy*dy+dz*dz */
 180             rsq_S0           = norm2(dx_S0, dy_S0, dz_S0);
 181             rsq_S1           = norm2(dx_S1, dy_S1, dz_S1);
 182             rsq_S2           = norm2(dx_S2, dy_S2, dz_S2);
 183             rsq_S3           = norm2(dx_S3, dy_S3, dz_S3);
 184
 185             wco_S0           = (rsq_S0 < rc2_S);
 186             wco_S1           = (rsq_S1 < rc2_S);
 187             wco_S2           = (rsq_S2 < rc2_S);
 188             wco_S3           = (rsq_S3 < rc2_S);
 189
 190             wco_any_S01      = wco_S0 || wco_S1;
 191             wco_any_S23      = wco_S2 || wco_S3;
 192             wco_any_S        = wco_any_S01 || wco_any_S23;
 193
 194             InRange          = anyTrue(wco_any_S);
 195
 196             *numDistanceChecks += 4*GMX_SIMD_REAL_WIDTH;
 197         }
 198         if (!InRange)
 199         {
 200             jclusterFirst++;
 201         }
 202     }
 203     if (!InRange)
 204     {
 205         return;
 206     }
 207
 208     InRange = FALSE;
 209     while (!InRange && jclusterLast > jclusterFirst)
 210     {
 211 #if NBNXN_SEARCH_BB_SIMD4
 212         d2 = subc_bb_dist2_simd4(0, bb_ci, jclusterLast, gridj->bbj);
 213 #else
 214         d2 = subc_bb_dist2(0, bb_ci, jclusterLast, gridj->bbj);
 215 #endif
 216         *numDistanceChecks += 2;
 217
 218         /* Check if the distance is within the distance where
 219          * we use only the bounding box distance rbb,
 220          * or within the cut-off and there is at least one atom pair
 221          * within the cut-off.
 222          */
 223         if (d2 < rbb2)
 224         {
 225             InRange = TRUE;
 226         }
 227         else if (d2 < rlist2)
 228         {
 229             xind_l  = xIndexFromCj<NbnxnLayout::Simd4xN>(cjFromCi<NbnxnLayout::Simd4xN>(gridj->cell0) + jclusterLast);
 230
 231             jx_S  = load<SimdReal>(x_j +xind_l + 0*STRIDE_S);
 232             jy_S  = load<SimdReal>(x_j +xind_l + 1*STRIDE_S);
 233             jz_S  = load<SimdReal>(x_j +xind_l + 2*STRIDE_S);
 234
 235             /* Calculate distance */
 236             dx_S0            = load<SimdReal>(x_ci_simd +  0*GMX_SIMD_REAL_WIDTH) - jx_S;
 237             dy_S0            = load<SimdReal>(x_ci_simd +  1*GMX_SIMD_REAL_WIDTH) - jy_S;
 238             dz_S0            = load<SimdReal>(x_ci_simd +  2*GMX_SIMD_REAL_WIDTH) - jz_S;
 239             dx_S1            = load<SimdReal>(x_ci_simd +  3*GMX_SIMD_REAL_WIDTH) - jx_S;
 240             dy_S1            = load<SimdReal>(x_ci_simd +  4*GMX_SIMD_REAL_WIDTH) - jy_S;
 241             dz_S1            = load<SimdReal>(x_ci_simd +  5*GMX_SIMD_REAL_WIDTH) - jz_S;
 242             dx_S2            = load<SimdReal>(x_ci_simd +  6*GMX_SIMD_REAL_WIDTH) - jx_S;
 243             dy_S2            = load<SimdReal>(x_ci_simd +  7*GMX_SIMD_REAL_WIDTH) - jy_S;
 244             dz_S2            = load<SimdReal>(x_ci_simd +  8*GMX_SIMD_REAL_WIDTH) - jz_S;
 245             dx_S3            = load<SimdReal>(x_ci_simd +  9*GMX_SIMD_REAL_WIDTH) - jx_S;
 246             dy_S3            = load<SimdReal>(x_ci_simd + 10*GMX_SIMD_REAL_WIDTH) - jy_S;
 247             dz_S3            = load<SimdReal>(x_ci_simd + 11*GMX_SIMD_REAL_WIDTH) - jz_S;
 248
 249             /* rsq = dx*dx+dy*dy+dz*dz */
 250             rsq_S0           = norm2(dx_S0, dy_S0, dz_S0);
 251             rsq_S1           = norm2(dx_S1, dy_S1, dz_S1);
 252             rsq_S2           = norm2(dx_S2, dy_S2, dz_S2);
 253             rsq_S3           = norm2(dx_S3, dy_S3, dz_S3);
 254
 255             wco_S0           = (rsq_S0 < rc2_S);
 256             wco_S1           = (rsq_S1 < rc2_S);
 257             wco_S2           = (rsq_S2 < rc2_S);
 258             wco_S3           = (rsq_S3 < rc2_S);
 259
 260             wco_any_S01      = wco_S0 || wco_S1;
 261             wco_any_S23      = wco_S2 || wco_S3;
 262             wco_any_S        = wco_any_S01 || wco_any_S23;
 263
 264             InRange          = anyTrue(wco_any_S);
 265
 266             *numDistanceChecks += 4*GMX_SIMD_REAL_WIDTH;
 267         }
 268         if (!InRange)
 269         {
 270             jclusterLast--;
 271         }
 272     }
 273
 274     if (jclusterFirst <= jclusterLast)
 275     {
 276         for (int jcluster = jclusterFirst; jcluster <= jclusterLast; jcluster++)
 277         {
 278             /* Store cj and the interaction mask */
 279             nbl->cj[nbl->ncj].cj   = cjFromCi<NbnxnLayout::Simd4xN>(gridj->cell0) + jcluster;
 280             nbl->cj[nbl->ncj].excl = get_imask_simd_4xn(excludeSubDiagonal, icluster, jcluster);
 281             nbl->ncj++;
 282         }
 283         /* Increase the closing index in i super-cell list */
 284         nbl->ci[nbl->nci].cj_ind_end = nbl->ncj;
 285     }
 286 }
 287
 288 #undef STRIDE_S