src/gromacs/nbnxm/pairlist_simd_4xm.h

   1 /*
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  36
  37 /*! \internal \file
  38  *
  39  * \brief
  40  * Declares inline-friendly code for making 4xN pairlists
  41  *
  42  * \author Berk Hess <hess@kth.se>
  43  * \ingroup module_nbnxm
  44  */
  45
  46 //! Stride of the packed x coordinate array
  47 static constexpr int c_xStride4xN =
  48         (GMX_SIMD_REAL_WIDTH > c_nbnxnCpuIClusterSize ? GMX_SIMD_REAL_WIDTH : c_nbnxnCpuIClusterSize);
  49
  50 //! Copies PBC shifted i-cell packed atom coordinates to working array
  51 static inline void icell_set_x_simd_4xn(int  ci,
  52                                         real shx,
  53                                         real shy,
  54                                         real shz,
  55                                         int gmx_unused        stride,
  56                                         const real*           x,
  57                                         NbnxnPairlistCpuWork* work)
  58 {
  59     int   ia;
  60     real* x_ci_simd = work->iClusterData.xSimd.data();
  61
  62     ia = xIndexFromCi<NbnxnLayout::Simd4xN>(ci);
  63
  64     store(x_ci_simd + 0 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0 * c_xStride4xN] + shx));
  65     store(x_ci_simd + 1 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1 * c_xStride4xN] + shy));
  66     store(x_ci_simd + 2 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2 * c_xStride4xN] + shz));
  67     store(x_ci_simd + 3 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0 * c_xStride4xN + 1] + shx));
  68     store(x_ci_simd + 4 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1 * c_xStride4xN + 1] + shy));
  69     store(x_ci_simd + 5 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2 * c_xStride4xN + 1] + shz));
  70     store(x_ci_simd + 6 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0 * c_xStride4xN + 2] + shx));
  71     store(x_ci_simd + 7 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1 * c_xStride4xN + 2] + shy));
  72     store(x_ci_simd + 8 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2 * c_xStride4xN + 2] + shz));
  73     store(x_ci_simd + 9 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 0 * c_xStride4xN + 3] + shx));
  74     store(x_ci_simd + 10 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 1 * c_xStride4xN + 3] + shy));
  75     store(x_ci_simd + 11 * GMX_SIMD_REAL_WIDTH, SimdReal(x[ia + 2 * c_xStride4xN + 3] + shz));
  76 }
  77
  78 /*! \brief SIMD code for checking and adding cluster-pairs to the list using coordinates in packed format.
  79  *
  80  * Checks bouding box distances and possibly atom pair distances.
  81  * This is an accelerated version of make_cluster_list_simple.
  82  *
  83  * \param[in]     jGrid               The j-grid
  84  * \param[in,out] nbl                 The pair-list to store the cluster pairs in
  85  * \param[in]     icluster            The index of the i-cluster
  86  * \param[in]     firstCell           The first cluster in the j-range, using i-cluster size indexing
  87  * \param[in]     lastCell            The last cluster in the j-range, using i-cluster size indexing
  88  * \param[in]     excludeSubDiagonal  Exclude atom pairs with i-index > j-index
  89  * \param[in]     x_j                 Coordinates for the j-atom, in SIMD packed format
  90  * \param[in]     rlist2              The squared list cut-off
  91  * \param[in]     rbb2                The squared cut-off for putting cluster-pairs in the list based on bounding box distance only
  92  * \param[in,out] numDistanceChecks   The number of distance checks performed
  93  */
  94 static inline void makeClusterListSimd4xn(const Grid&       jGrid,
  95                                           NbnxnPairlistCpu* nbl,
  96                                           int               icluster,
  97                                           int               firstCell,
  98                                           int               lastCell,
  99                                           bool              excludeSubDiagonal,
 100                                           const real* gmx_restrict x_j,
 101                                           real                     rlist2,
 102                                           float                    rbb2,
 103                                           int* gmx_restrict numDistanceChecks)
 104 {
 105     using namespace gmx;
 106     const real* gmx_restrict x_ci_simd    = nbl->work->iClusterData.xSimd.data();
 107     const BoundingBox* gmx_restrict bb_ci = nbl->work->iClusterData.bb.data();
 108
 109     SimdReal jx_S, jy_S, jz_S;
 110
 111     SimdReal dx_S0, dy_S0, dz_S0;
 112     SimdReal dx_S1, dy_S1, dz_S1;
 113     SimdReal dx_S2, dy_S2, dz_S2;
 114     SimdReal dx_S3, dy_S3, dz_S3;
 115
 116     SimdReal rsq_S0;
 117     SimdReal rsq_S1;
 118     SimdReal rsq_S2;
 119     SimdReal rsq_S3;
 120
 121     SimdBool wco_S0;
 122     SimdBool wco_S1;
 123     SimdBool wco_S2;
 124     SimdBool wco_S3;
 125     SimdBool wco_any_S01, wco_any_S23, wco_any_S;
 126
 127     SimdReal rc2_S;
 128
 129     gmx_bool InRange;
 130     float    d2;
 131     int      xind_f, xind_l;
 132
 133     /* Convert the j-range from i-cluster size indexing to j-cluster indexing */
 134     int jclusterFirst = cjFromCi<NbnxnLayout::Simd4xN, 0>(firstCell);
 135     int jclusterLast  = cjFromCi<NbnxnLayout::Simd4xN, 1>(lastCell);
 136     GMX_ASSERT(jclusterLast >= jclusterFirst,
 137                "We should have a non-empty j-cluster range, since the calling code should have "
 138                "ensured a non-empty cell range");
 139
 140     rc2_S = SimdReal(rlist2);
 141
 142     InRange = FALSE;
 143     while (!InRange && jclusterFirst <= jclusterLast)
 144     {
 145         d2 = clusterBoundingBoxDistance2(bb_ci[0], jGrid.jBoundingBoxes()[jclusterFirst]);
 146         *numDistanceChecks += 2;
 147
 148         /* Check if the distance is within the distance where
 149          * we use only the bounding box distance rbb,
 150          * or within the cut-off and there is at least one atom pair
 151          * within the cut-off.
 152          */
 153         if (d2 < rbb2)
 154         {
 155             InRange = TRUE;
 156         }
 157         else if (d2 < rlist2)
 158         {
 159             xind_f = xIndexFromCj<NbnxnLayout::Simd4xN>(
 160                     cjFromCi<NbnxnLayout::Simd4xN, 0>(jGrid.cellOffset()) + jclusterFirst);
 161
 162             jx_S = load<SimdReal>(x_j + xind_f + 0 * c_xStride4xN);
 163             jy_S = load<SimdReal>(x_j + xind_f + 1 * c_xStride4xN);
 164             jz_S = load<SimdReal>(x_j + xind_f + 2 * c_xStride4xN);
 165
 166
 167             /* Calculate distance */
 168             dx_S0 = load<SimdReal>(x_ci_simd + 0 * GMX_SIMD_REAL_WIDTH) - jx_S;
 169             dy_S0 = load<SimdReal>(x_ci_simd + 1 * GMX_SIMD_REAL_WIDTH) - jy_S;
 170             dz_S0 = load<SimdReal>(x_ci_simd + 2 * GMX_SIMD_REAL_WIDTH) - jz_S;
 171             dx_S1 = load<SimdReal>(x_ci_simd + 3 * GMX_SIMD_REAL_WIDTH) - jx_S;
 172             dy_S1 = load<SimdReal>(x_ci_simd + 4 * GMX_SIMD_REAL_WIDTH) - jy_S;
 173             dz_S1 = load<SimdReal>(x_ci_simd + 5 * GMX_SIMD_REAL_WIDTH) - jz_S;
 174             dx_S2 = load<SimdReal>(x_ci_simd + 6 * GMX_SIMD_REAL_WIDTH) - jx_S;
 175             dy_S2 = load<SimdReal>(x_ci_simd + 7 * GMX_SIMD_REAL_WIDTH) - jy_S;
 176             dz_S2 = load<SimdReal>(x_ci_simd + 8 * GMX_SIMD_REAL_WIDTH) - jz_S;
 177             dx_S3 = load<SimdReal>(x_ci_simd + 9 * GMX_SIMD_REAL_WIDTH) - jx_S;
 178             dy_S3 = load<SimdReal>(x_ci_simd + 10 * GMX_SIMD_REAL_WIDTH) - jy_S;
 179             dz_S3 = load<SimdReal>(x_ci_simd + 11 * GMX_SIMD_REAL_WIDTH) - jz_S;
 180
 181             /* rsq = dx*dx+dy*dy+dz*dz */
 182             rsq_S0 = norm2(dx_S0, dy_S0, dz_S0);
 183             rsq_S1 = norm2(dx_S1, dy_S1, dz_S1);
 184             rsq_S2 = norm2(dx_S2, dy_S2, dz_S2);
 185             rsq_S3 = norm2(dx_S3, dy_S3, dz_S3);
 186
 187             wco_S0 = (rsq_S0 < rc2_S);
 188             wco_S1 = (rsq_S1 < rc2_S);
 189             wco_S2 = (rsq_S2 < rc2_S);
 190             wco_S3 = (rsq_S3 < rc2_S);
 191
 192             wco_any_S01 = wco_S0 || wco_S1;
 193             wco_any_S23 = wco_S2 || wco_S3;
 194             wco_any_S   = wco_any_S01 || wco_any_S23;
 195
 196             InRange = anyTrue(wco_any_S);
 197
 198             *numDistanceChecks += 4 * GMX_SIMD_REAL_WIDTH;
 199         }
 200         if (!InRange)
 201         {
 202             jclusterFirst++;
 203         }
 204     }
 205     if (!InRange)
 206     {
 207         return;
 208     }
 209
 210     InRange = FALSE;
 211     while (!InRange && jclusterLast > jclusterFirst)
 212     {
 213         d2 = clusterBoundingBoxDistance2(bb_ci[0], jGrid.jBoundingBoxes()[jclusterLast]);
 214         *numDistanceChecks += 2;
 215
 216         /* Check if the distance is within the distance where
 217          * we use only the bounding box distance rbb,
 218          * or within the cut-off and there is at least one atom pair
 219          * within the cut-off.
 220          */
 221         if (d2 < rbb2)
 222         {
 223             InRange = TRUE;
 224         }
 225         else if (d2 < rlist2)
 226         {
 227             xind_l = xIndexFromCj<NbnxnLayout::Simd4xN>(
 228                     cjFromCi<NbnxnLayout::Simd4xN, 0>(jGrid.cellOffset()) + jclusterLast);
 229
 230             jx_S = load<SimdReal>(x_j + xind_l + 0 * c_xStride4xN);
 231             jy_S = load<SimdReal>(x_j + xind_l + 1 * c_xStride4xN);
 232             jz_S = load<SimdReal>(x_j + xind_l + 2 * c_xStride4xN);
 233
 234             /* Calculate distance */
 235             dx_S0 = load<SimdReal>(x_ci_simd + 0 * GMX_SIMD_REAL_WIDTH) - jx_S;
 236             dy_S0 = load<SimdReal>(x_ci_simd + 1 * GMX_SIMD_REAL_WIDTH) - jy_S;
 237             dz_S0 = load<SimdReal>(x_ci_simd + 2 * GMX_SIMD_REAL_WIDTH) - jz_S;
 238             dx_S1 = load<SimdReal>(x_ci_simd + 3 * GMX_SIMD_REAL_WIDTH) - jx_S;
 239             dy_S1 = load<SimdReal>(x_ci_simd + 4 * GMX_SIMD_REAL_WIDTH) - jy_S;
 240             dz_S1 = load<SimdReal>(x_ci_simd + 5 * GMX_SIMD_REAL_WIDTH) - jz_S;
 241             dx_S2 = load<SimdReal>(x_ci_simd + 6 * GMX_SIMD_REAL_WIDTH) - jx_S;
 242             dy_S2 = load<SimdReal>(x_ci_simd + 7 * GMX_SIMD_REAL_WIDTH) - jy_S;
 243             dz_S2 = load<SimdReal>(x_ci_simd + 8 * GMX_SIMD_REAL_WIDTH) - jz_S;
 244             dx_S3 = load<SimdReal>(x_ci_simd + 9 * GMX_SIMD_REAL_WIDTH) - jx_S;
 245             dy_S3 = load<SimdReal>(x_ci_simd + 10 * GMX_SIMD_REAL_WIDTH) - jy_S;
 246             dz_S3 = load<SimdReal>(x_ci_simd + 11 * GMX_SIMD_REAL_WIDTH) - jz_S;
 247
 248             /* rsq = dx*dx+dy*dy+dz*dz */
 249             rsq_S0 = norm2(dx_S0, dy_S0, dz_S0);
 250             rsq_S1 = norm2(dx_S1, dy_S1, dz_S1);
 251             rsq_S2 = norm2(dx_S2, dy_S2, dz_S2);
 252             rsq_S3 = norm2(dx_S3, dy_S3, dz_S3);
 253
 254             wco_S0 = (rsq_S0 < rc2_S);
 255             wco_S1 = (rsq_S1 < rc2_S);
 256             wco_S2 = (rsq_S2 < rc2_S);
 257             wco_S3 = (rsq_S3 < rc2_S);
 258
 259             wco_any_S01 = wco_S0 || wco_S1;
 260             wco_any_S23 = wco_S2 || wco_S3;
 261             wco_any_S   = wco_any_S01 || wco_any_S23;
 262
 263             InRange = anyTrue(wco_any_S);
 264
 265             *numDistanceChecks += 4 * GMX_SIMD_REAL_WIDTH;
 266         }
 267         if (!InRange)
 268         {
 269             jclusterLast--;
 270         }
 271     }
 272
 273     if (jclusterFirst <= jclusterLast)
 274     {
 275         for (int jcluster = jclusterFirst; jcluster <= jclusterLast; jcluster++)
 276         {
 277             /* Store cj and the interaction mask */
 278             nbnxn_cj_t cjEntry;
 279             cjEntry.cj   = cjFromCi<NbnxnLayout::Simd4xN, 0>(jGrid.cellOffset()) + jcluster;
 280             cjEntry.excl = get_imask_simd_4xn(excludeSubDiagonal, icluster, jcluster);
 281             nbl->cj.push_back(cjEntry);
 282         }
 283         /* Increase the closing index in the i list */
 284         nbl->ci.back().cj_ind_end = nbl->cj.size();
 285     }
 286 }