src/mdlib/nbnxn_search_simd_2xnn.h

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  38
  39 /* Get the half-width SIMD stuff from the kernel utils files */
  40 #include "nbnxn_kernels/nbnxn_kernel_simd_utils.h"
  41
  42
  43 #if GMX_SIMD_WIDTH_HERE >= 2*NBNXN_CPU_CLUSTER_I_SIZE
  44 #define STRIDE_S  (GMX_SIMD_WIDTH_HERE/2)
  45 #else
  46 #define STRIDE_S  NBNXN_CPU_CLUSTER_I_SIZE
  47 #endif
  48
  49 static gmx_inline gmx_mm_pr gmx_load_hpr_hilo_pr(const real *a)
  50 {
  51     gmx_mm_hpr a_S;
  52     gmx_mm_pr  a_a_S;
  53
  54     gmx_load_hpr(&a_S, a);
  55
  56     gmx_2hpr_to_pr(a_S, a_S, &a_a_S);
  57
  58     return a_a_S;
  59 }
  60
  61 static gmx_inline gmx_mm_pr gmx_set_2real_shift_pr(const real *a, real shift)
  62 {
  63     gmx_mm_hpr a0_S, a1_S;
  64     gmx_mm_pr  a0_a1_S;
  65
  66     gmx_set1_hpr(&a0_S, a[0] + shift);
  67     gmx_set1_hpr(&a1_S, a[1] + shift);
  68
  69     gmx_2hpr_to_pr(a0_S, a1_S, &a0_a1_S);
  70
  71     return a0_a1_S;
  72 }
  73
  74 /* Copies PBC shifted i-cell packed atom coordinates to working array */
  75 static gmx_inline void
  76 icell_set_x_simd_2xnn(int ci,
  77                       real shx, real shy, real shz,
  78                       int na_c,
  79                       int stride, const real *x,
  80                       nbnxn_list_work_t *work)
  81 {
  82     int                     ia;
  83     nbnxn_x_ci_simd_2xnn_t *x_ci;
  84
  85     x_ci = work->x_ci_simd_2xnn;
  86
  87     ia = X_IND_CI_SIMD_2XNN(ci);
  88
  89     x_ci->ix_S0 = gmx_set_2real_shift_pr(x + ia + 0*STRIDE_S + 0, shx);
  90     x_ci->iy_S0 = gmx_set_2real_shift_pr(x + ia + 1*STRIDE_S + 0, shy);
  91     x_ci->iz_S0 = gmx_set_2real_shift_pr(x + ia + 2*STRIDE_S + 0, shz);
  92     x_ci->ix_S2 = gmx_set_2real_shift_pr(x + ia + 0*STRIDE_S + 2, shx);
  93     x_ci->iy_S2 = gmx_set_2real_shift_pr(x + ia + 1*STRIDE_S + 2, shy);
  94     x_ci->iz_S2 = gmx_set_2real_shift_pr(x + ia + 2*STRIDE_S + 2, shz);
  95 }
  96
  97 /* SIMD code for making a pair list of cell ci vs cell cjf-cjl
  98  * for coordinates in packed format.
  99  * Checks bouding box distances and possibly atom pair distances.
 100  * This is an accelerated version of make_cluster_list_simple.
 101  */
 102 static gmx_inline void
 103 make_cluster_list_simd_2xnn(const nbnxn_grid_t *gridj,
 104                             nbnxn_pairlist_t *nbl,
 105                             int ci, int cjf, int cjl,
 106                             gmx_bool remove_sub_diag,
 107                             const real *x_j,
 108                             real rl2, float rbb2,
 109                             int *ndistc)
 110 {
 111     const nbnxn_x_ci_simd_2xnn_t *work;
 112     const nbnxn_bb_t             *bb_ci;
 113
 114     gmx_mm_pr                     jx_S, jy_S, jz_S;
 115
 116     gmx_mm_pr                     dx_S0, dy_S0, dz_S0;
 117     gmx_mm_pr                     dx_S2, dy_S2, dz_S2;
 118
 119     gmx_mm_pr                     rsq_S0;
 120     gmx_mm_pr                     rsq_S2;
 121
 122     gmx_mm_pb                     wco_S0;
 123     gmx_mm_pb                     wco_S2;
 124     gmx_mm_pb                     wco_any_S;
 125
 126     gmx_mm_pr                     rc2_S;
 127
 128     gmx_bool                      InRange;
 129     float                         d2;
 130     int                           xind_f, xind_l, cj;
 131
 132     cjf = CI_TO_CJ_SIMD_2XNN(cjf);
 133     cjl = CI_TO_CJ_SIMD_2XNN(cjl+1) - 1;
 134
 135     work = nbl->work->x_ci_simd_2xnn;
 136
 137     bb_ci = nbl->work->bb_ci;
 138
 139     rc2_S   = gmx_set1_pr(rl2);
 140
 141     InRange = FALSE;
 142     while (!InRange && cjf <= cjl)
 143     {
 144 #ifdef NBNXN_SEARCH_BB_SIMD4
 145         d2 = subc_bb_dist2_simd4(0, bb_ci, cjf, gridj->bbj);
 146 #else
 147         d2 = subc_bb_dist2(0, bb_ci, cjf, gridj->bbj);
 148 #endif
 149         *ndistc += 2;
 150
 151         /* Check if the distance is within the distance where
 152          * we use only the bounding box distance rbb,
 153          * or within the cut-off and there is at least one atom pair
 154          * within the cut-off.
 155          */
 156         if (d2 < rbb2)
 157         {
 158             InRange = TRUE;
 159         }
 160         else if (d2 < rl2)
 161         {
 162             xind_f  = X_IND_CJ_SIMD_2XNN(CI_TO_CJ_SIMD_2XNN(gridj->cell0) + cjf);
 163
 164             jx_S  = gmx_load_hpr_hilo_pr(x_j+xind_f+0*STRIDE_S);
 165             jy_S  = gmx_load_hpr_hilo_pr(x_j+xind_f+1*STRIDE_S);
 166             jz_S  = gmx_load_hpr_hilo_pr(x_j+xind_f+2*STRIDE_S);
 167
 168             /* Calculate distance */
 169             dx_S0            = gmx_sub_pr(work->ix_S0, jx_S);
 170             dy_S0            = gmx_sub_pr(work->iy_S0, jy_S);
 171             dz_S0            = gmx_sub_pr(work->iz_S0, jz_S);
 172             dx_S2            = gmx_sub_pr(work->ix_S2, jx_S);
 173             dy_S2            = gmx_sub_pr(work->iy_S2, jy_S);
 174             dz_S2            = gmx_sub_pr(work->iz_S2, jz_S);
 175
 176             /* rsq = dx*dx+dy*dy+dz*dz */
 177             rsq_S0           = gmx_calc_rsq_pr(dx_S0, dy_S0, dz_S0);
 178             rsq_S2           = gmx_calc_rsq_pr(dx_S2, dy_S2, dz_S2);
 179
 180             wco_S0           = gmx_cmplt_pr(rsq_S0, rc2_S);
 181             wco_S2           = gmx_cmplt_pr(rsq_S2, rc2_S);
 182
 183             wco_any_S        = gmx_or_pb(wco_S0, wco_S2);
 184
 185             InRange          = gmx_anytrue_pb(wco_any_S);
 186
 187             *ndistc += 2*GMX_SIMD_WIDTH_HERE;
 188         }
 189         if (!InRange)
 190         {
 191             cjf++;
 192         }
 193     }
 194     if (!InRange)
 195     {
 196         return;
 197     }
 198
 199     InRange = FALSE;
 200     while (!InRange && cjl > cjf)
 201     {
 202 #ifdef NBNXN_SEARCH_BB_SIMD4
 203         d2 = subc_bb_dist2_simd4(0, bb_ci, cjl, gridj->bbj);
 204 #else
 205         d2 = subc_bb_dist2(0, bb_ci, cjl, gridj->bbj);
 206 #endif
 207         *ndistc += 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 < rl2)
 219         {
 220             xind_l  = X_IND_CJ_SIMD_2XNN(CI_TO_CJ_SIMD_2XNN(gridj->cell0) + cjl);
 221
 222             jx_S  = gmx_load_hpr_hilo_pr(x_j+xind_l+0*STRIDE_S);
 223             jy_S  = gmx_load_hpr_hilo_pr(x_j+xind_l+1*STRIDE_S);
 224             jz_S  = gmx_load_hpr_hilo_pr(x_j+xind_l+2*STRIDE_S);
 225
 226             /* Calculate distance */
 227             dx_S0            = gmx_sub_pr(work->ix_S0, jx_S);
 228             dy_S0            = gmx_sub_pr(work->iy_S0, jy_S);
 229             dz_S0            = gmx_sub_pr(work->iz_S0, jz_S);
 230             dx_S2            = gmx_sub_pr(work->ix_S2, jx_S);
 231             dy_S2            = gmx_sub_pr(work->iy_S2, jy_S);
 232             dz_S2            = gmx_sub_pr(work->iz_S2, jz_S);
 233
 234             /* rsq = dx*dx+dy*dy+dz*dz */
 235             rsq_S0           = gmx_calc_rsq_pr(dx_S0, dy_S0, dz_S0);
 236             rsq_S2           = gmx_calc_rsq_pr(dx_S2, dy_S2, dz_S2);
 237
 238             wco_S0           = gmx_cmplt_pr(rsq_S0, rc2_S);
 239             wco_S2           = gmx_cmplt_pr(rsq_S2, rc2_S);
 240
 241             wco_any_S        = gmx_or_pb(wco_S0, wco_S2);
 242
 243             InRange          = gmx_anytrue_pb(wco_any_S);
 244
 245             *ndistc += 2*GMX_SIMD_WIDTH_HERE;
 246         }
 247         if (!InRange)
 248         {
 249             cjl--;
 250         }
 251     }
 252
 253     if (cjf <= cjl)
 254     {
 255         for (cj = cjf; cj <= cjl; cj++)
 256         {
 257             /* Store cj and the interaction mask */
 258             nbl->cj[nbl->ncj].cj   = CI_TO_CJ_SIMD_2XNN(gridj->cell0) + cj;
 259             nbl->cj[nbl->ncj].excl = get_imask_simd_2xnn(remove_sub_diag, ci, cj);
 260             nbl->ncj++;
 261         }
 262         /* Increase the closing index in i super-cell list */
 263         nbl->ci[nbl->nci].cj_ind_end = nbl->ncj;
 264     }
 265 }
 266
 267 #undef STRIDE_S