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38 #include "nbnxn_kernel_simd_2xnn_prune.h"
40 #include "gromacs/mdlib/nbnxn_pairlist.h"
41 #include "gromacs/mdlib/nbnxn_simd.h"
42 #include "gromacs/utility/gmxassert.h"
44 #ifdef GMX_NBNXN_SIMD_2XNN
45 #define GMX_SIMD_J_UNROLL_SIZE 2
46 #include "gromacs/mdlib/nbnxn_kernels/simd_2xnn/nbnxn_kernel_simd_2xnn_common.h"
49 /* Prune a single nbnxn_pairtlist_t entry with distance rlistInner */
51 nbnxn_kernel_prune_2xnn(nbnxn_pairlist_t * nbl,
52 const nbnxn_atomdata_t * nbat,
53 const rvec * gmx_restrict shift_vec,
56 #ifdef GMX_NBNXN_SIMD_2XNN
58 const nbnxn_ci_t * gmx_restrict ciOuter = nbl->ciOuter;
59 nbnxn_ci_t * gmx_restrict ciInner = nbl->ci;
61 const nbnxn_cj_t * gmx_restrict cjOuter = nbl->cjOuter;
62 nbnxn_cj_t * gmx_restrict cjInner = nbl->cj;
64 const real * gmx_restrict shiftvec = shift_vec[0];
65 const real * gmx_restrict x = nbat->x;
67 const SimdReal rlist2_S(rlistInner*rlistInner);
69 /* Initialize the new list as empty and add pairs that are in range */
72 for (int i = 0; i < nbl->nciOuter; i++)
74 const nbnxn_ci_t * gmx_restrict ciEntry = &ciOuter[i];
76 /* Copy the original list entry to the pruned entry */
77 ciInner[nciInner].ci = ciEntry->ci;
78 ciInner[nciInner].shift = ciEntry->shift;
79 ciInner[nciInner].cj_ind_start = ncjInner;
81 /* Extract shift data */
82 int ish = (ciEntry->shift & NBNXN_CI_SHIFT);
86 SimdReal shX_S = SimdReal(shiftvec[ish3 ]);
87 SimdReal shY_S = SimdReal(shiftvec[ish3 + 1]);
88 SimdReal shZ_S = SimdReal(shiftvec[ish3 + 2]);
91 int scix = ci*STRIDE*DIM;
93 int scix = (ci >> 1)*STRIDE*DIM + (ci & 1)*(STRIDE >> 1);
96 /* Load i atom data */
97 int sciy = scix + STRIDE;
98 int sciz = sciy + STRIDE;
99 SimdReal ix_S0 = loadU1DualHsimd(x + scix ) + shX_S;
100 SimdReal ix_S2 = loadU1DualHsimd(x + scix + 2) + shX_S;
101 SimdReal iy_S0 = loadU1DualHsimd(x + sciy ) + shY_S;
102 SimdReal iy_S2 = loadU1DualHsimd(x + sciy + 2) + shY_S;
103 SimdReal iz_S0 = loadU1DualHsimd(x + sciz ) + shZ_S;
104 SimdReal iz_S2 = loadU1DualHsimd(x + sciz + 2) + shZ_S;
106 for (int cjind = ciEntry->cj_ind_start; cjind < ciEntry->cj_ind_end; cjind++)
108 /* j-cluster index */
109 int cj = cjOuter[cjind].cj;
111 /* Atom indices (of the first atom in the cluster) */
112 #if UNROLLJ == STRIDE
116 int ajx = (cj >> 1)*DIM*STRIDE + (cj & 1)*UNROLLJ;
118 int ajy = ajx + STRIDE;
119 int ajz = ajy + STRIDE;
121 /* load j atom coordinates */
122 SimdReal jx_S = loadDuplicateHsimd(x + ajx);
123 SimdReal jy_S = loadDuplicateHsimd(x + ajy);
124 SimdReal jz_S = loadDuplicateHsimd(x + ajz);
126 /* Calculate distance */
127 SimdReal dx_S0 = ix_S0 - jx_S;
128 SimdReal dy_S0 = iy_S0 - jy_S;
129 SimdReal dz_S0 = iz_S0 - jz_S;
130 SimdReal dx_S2 = ix_S2 - jx_S;
131 SimdReal dy_S2 = iy_S2 - jy_S;
132 SimdReal dz_S2 = iz_S2 - jz_S;
134 /* rsq = dx*dx+dy*dy+dz*dz */
135 SimdReal rsq_S0 = norm2(dx_S0, dy_S0, dz_S0);
136 SimdReal rsq_S2 = norm2(dx_S2, dy_S2, dz_S2);
138 /* Do the cut-off check */
139 SimdBool wco_S0 = (rsq_S0 < rlist2_S);
140 SimdBool wco_S2 = (rsq_S2 < rlist2_S);
142 wco_S0 = wco_S0 || wco_S2;
144 /* Putting the assignment inside the conditional is slower */
145 cjInner[ncjInner] = cjOuter[cjind];
152 if (ncjInner > ciInner[nciInner].cj_ind_start)
154 ciInner[nciInner].cj_ind_end = ncjInner;
161 #else /* GMX_NBNXN_SIMD_2XNN */
163 GMX_RELEASE_ASSERT(false, "2xNN kernel called without 2xNN support");
165 GMX_UNUSED_VALUE(nbl);
166 GMX_UNUSED_VALUE(nbat);
167 GMX_UNUSED_VALUE(shift_vec);
168 GMX_UNUSED_VALUE(rlistInner);
170 #endif /* GMX_NBNXN_SIMD_2XNN */