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38 const nbnxn_ci_t *nbln;
39 const nbnxn_cj_t *l_cj;
46 gmx_bool do_LJ, half_LJ, do_coul;
47 int cjind0, cjind1, cjind;
51 int egps_ishift, egps_imask;
52 int egps_jshift, egps_jmask, egps_jstride;
54 real *vvdwtp[UNROLLI];
61 SimdReal ix_S0, iy_S0, iz_S0;
62 SimdReal ix_S1, iy_S1, iz_S1;
63 SimdReal ix_S2, iy_S2, iz_S2;
64 SimdReal ix_S3, iy_S3, iz_S3;
65 SimdReal fix_S0, fiy_S0, fiz_S0;
66 SimdReal fix_S1, fiy_S1, fiz_S1;
67 SimdReal fix_S2, fiy_S2, fiz_S2;
68 SimdReal fix_S3, fiy_S3, fiz_S3;
70 SimdReal diagonal_jmi_S;
71 #if UNROLLI == UNROLLJ
72 SimdBool diagonal_mask_S0, diagonal_mask_S1, diagonal_mask_S2, diagonal_mask_S3;
74 SimdBool diagonal_mask0_S0, diagonal_mask0_S1, diagonal_mask0_S2, diagonal_mask0_S3;
75 SimdBool diagonal_mask1_S0, diagonal_mask1_S1, diagonal_mask1_S2, diagonal_mask1_S3;
78 #if GMX_DOUBLE && !GMX_SIMD_HAVE_INT32_LOGICAL
79 std::uint64_t *exclusion_filter;
81 std::uint32_t *exclusion_filter;
83 SimdBitMask filter_S0, filter_S1, filter_S2, filter_S3;
88 SimdReal iq_S0 = setZero();
89 SimdReal iq_S1 = setZero();
90 SimdReal iq_S2 = setZero();
91 SimdReal iq_S3 = setZero();
96 SimdReal hrc_3_S, moh_rc_S;
101 /* Coulomb table variables */
103 const real * tab_coul_F;
105 const real gmx_unused *tab_coul_V;
112 #ifdef CALC_COUL_EWALD
113 SimdReal beta2_S, beta_S;
116 #if defined CALC_ENERGIES && (defined CALC_COUL_EWALD || defined CALC_COUL_TAB)
120 #if defined LJ_CUT && defined CALC_ENERGIES
121 SimdReal p6_cpot_S, p12_cpot_S;
125 SimdReal swV3_S, swV4_S, swV5_S;
126 SimdReal swF2_S, swF3_S, swF4_S;
128 #ifdef LJ_FORCE_SWITCH
130 SimdReal p6_fc2_S, p6_fc3_S;
131 SimdReal p12_fc2_S, p12_fc3_S;
133 SimdReal p6_vc3_S, p6_vc4_S;
134 SimdReal p12_vc3_S, p12_vc4_S;
135 SimdReal p6_6cpot_S, p12_12cpot_S;
139 real lj_ewaldcoeff2, lj_ewaldcoeff6_6;
140 SimdReal mone_S, half_S, lje_c2_S, lje_c6_6_S;
146 SimdReal hsig_i_S0, seps_i_S0;
147 SimdReal hsig_i_S1, seps_i_S1;
148 SimdReal hsig_i_S2, seps_i_S2;
149 SimdReal hsig_i_S3, seps_i_S3;
152 #if defined LJ_COMB_GEOM || defined LJ_EWALD_GEOM
155 #endif /* LJ_COMB_LB */
159 #ifdef VDW_CUTOFF_CHECK
169 #if defined LJ_COMB_GEOM || defined LJ_COMB_LB || defined LJ_EWALD_GEOM
172 #if !(defined LJ_COMB_GEOM || defined LJ_COMB_LB || defined FIX_LJ_C)
173 /* No combination rule used */
174 real *nbfp_ptr = nbat->nbfp_aligned;
175 const int *type = nbat->type;
178 /* Load j-i for the first i */
179 diagonal_jmi_S = load<SimdReal>(nbat->simd_4xn_diagonal_j_minus_i);
180 /* Generate all the diagonal masks as comparison results */
181 #if UNROLLI == UNROLLJ
182 diagonal_mask_S0 = (zero_S < diagonal_jmi_S);
183 diagonal_jmi_S = diagonal_jmi_S - one_S;
184 diagonal_mask_S1 = (zero_S < diagonal_jmi_S);
185 diagonal_jmi_S = diagonal_jmi_S - one_S;
186 diagonal_mask_S2 = (zero_S < diagonal_jmi_S);
187 diagonal_jmi_S = diagonal_jmi_S - one_S;
188 diagonal_mask_S3 = (zero_S < diagonal_jmi_S);
190 #if UNROLLI == 2*UNROLLJ || 2*UNROLLI == UNROLLJ
191 diagonal_mask0_S0 = (zero_S < diagonal_jmi_S);
192 diagonal_jmi_S = diagonal_jmi_S - one_S;
193 diagonal_mask0_S1 = (zero_S < diagonal_jmi_S);
194 diagonal_jmi_S = diagonal_jmi_S - one_S;
195 diagonal_mask0_S2 = (zero_S < diagonal_jmi_S);
196 diagonal_jmi_S = diagonal_jmi_S - one_S;
197 diagonal_mask0_S3 = (zero_S < diagonal_jmi_S);
198 diagonal_jmi_S = diagonal_jmi_S - one_S;
200 #if UNROLLI == 2*UNROLLJ
201 /* Load j-i for the second half of the j-cluster */
202 diagonal_jmi_S = load<SimdReal>(nbat->simd_4xn_diagonal_j_minus_i + UNROLLJ);
205 diagonal_mask1_S0 = (zero_S < diagonal_jmi_S);
206 diagonal_jmi_S = diagonal_jmi_S - one_S;
207 diagonal_mask1_S1 = (zero_S < diagonal_jmi_S);
208 diagonal_jmi_S = diagonal_jmi_S - one_S;
209 diagonal_mask1_S2 = (zero_S < diagonal_jmi_S);
210 diagonal_jmi_S = diagonal_jmi_S - one_S;
211 diagonal_mask1_S3 = (zero_S < diagonal_jmi_S);
215 #if GMX_DOUBLE && !GMX_SIMD_HAVE_INT32_LOGICAL
216 exclusion_filter = nbat->simd_exclusion_filter64;
218 exclusion_filter = nbat->simd_exclusion_filter;
221 /* Here we cast the exclusion filters from unsigned * to int * or real *.
222 * Since we only check bits, the actual value they represent does not
223 * matter, as long as both filter and mask data are treated the same way.
225 #if GMX_SIMD_HAVE_INT32_LOGICAL
226 filter_S0 = load<SimdBitMask>(reinterpret_cast<const int *>(exclusion_filter + 0*UNROLLJ));
227 filter_S1 = load<SimdBitMask>(reinterpret_cast<const int *>(exclusion_filter + 1*UNROLLJ));
228 filter_S2 = load<SimdBitMask>(reinterpret_cast<const int *>(exclusion_filter + 2*UNROLLJ));
229 filter_S3 = load<SimdBitMask>(reinterpret_cast<const int *>(exclusion_filter + 3*UNROLLJ));
231 filter_S0 = load<SimdBitMask>(reinterpret_cast<const real *>(exclusion_filter + 0*UNROLLJ));
232 filter_S1 = load<SimdBitMask>(reinterpret_cast<const real *>(exclusion_filter + 1*UNROLLJ));
233 filter_S2 = load<SimdBitMask>(reinterpret_cast<const real *>(exclusion_filter + 2*UNROLLJ));
234 filter_S3 = load<SimdBitMask>(reinterpret_cast<const real *>(exclusion_filter + 3*UNROLLJ));
238 /* Reaction-field constants */
239 mrc_3_S = SimdReal(-2*ic->k_rf);
241 hrc_3_S = SimdReal(ic->k_rf);
242 moh_rc_S = SimdReal(-ic->c_rf);
248 invtsp_S = SimdReal(ic->tabq_scale);
250 mhalfsp_S = SimdReal(-0.5/ic->tabq_scale);
254 tab_coul_F = ic->tabq_coul_FDV0;
256 tab_coul_F = ic->tabq_coul_F;
257 tab_coul_V = ic->tabq_coul_V;
259 #endif /* CALC_COUL_TAB */
261 #ifdef CALC_COUL_EWALD
262 beta2_S = SimdReal(ic->ewaldcoeff_q*ic->ewaldcoeff_q);
263 beta_S = SimdReal(ic->ewaldcoeff_q);
266 #if (defined CALC_COUL_TAB || defined CALC_COUL_EWALD) && defined CALC_ENERGIES
267 sh_ewald_S = SimdReal(ic->sh_ewald);
270 /* LJ function constants */
271 #if defined CALC_ENERGIES || defined LJ_POT_SWITCH
272 SimdReal sixth_S(1.0/6.0);
273 SimdReal twelveth_S(1.0/12.0);
276 #if defined LJ_CUT && defined CALC_ENERGIES
277 /* We shift the potential by cpot, which can be zero */
278 p6_cpot_S = SimdReal(ic->dispersion_shift.cpot);
279 p12_cpot_S = SimdReal(ic->repulsion_shift.cpot);
282 rswitch_S = SimdReal(ic->rvdw_switch);
283 swV3_S = SimdReal(ic->vdw_switch.c3);
284 swV4_S = SimdReal(ic->vdw_switch.c4);
285 swV5_S = SimdReal(ic->vdw_switch.c5);
286 swF2_S = SimdReal(3*ic->vdw_switch.c3);
287 swF3_S = SimdReal(4*ic->vdw_switch.c4);
288 swF4_S = SimdReal(5*ic->vdw_switch.c5);
290 #ifdef LJ_FORCE_SWITCH
291 rswitch_S = SimdReal(ic->rvdw_switch);
292 p6_fc2_S = SimdReal(ic->dispersion_shift.c2);
293 p6_fc3_S = SimdReal(ic->dispersion_shift.c3);
294 p12_fc2_S = SimdReal(ic->repulsion_shift.c2);
295 p12_fc3_S = SimdReal(ic->repulsion_shift.c3);
298 SimdReal mthird_S(-1.0/3.0);
299 SimdReal mfourth_S(-1.0/4.0);
301 p6_vc3_S = mthird_S * p6_fc2_S;
302 p6_vc4_S = mfourth_S * p6_fc3_S;
303 p6_6cpot_S = SimdReal(ic->dispersion_shift.cpot/6);
304 p12_vc3_S = mthird_S * p12_fc2_S;
305 p12_vc4_S = mfourth_S * p12_fc3_S;
306 p12_12cpot_S = SimdReal(ic->repulsion_shift.cpot/12);
311 mone_S = SimdReal(-1.0);
312 half_S = SimdReal(0.5);
313 lj_ewaldcoeff2 = ic->ewaldcoeff_lj*ic->ewaldcoeff_lj;
314 lj_ewaldcoeff6_6 = lj_ewaldcoeff2*lj_ewaldcoeff2*lj_ewaldcoeff2/6;
315 lje_c2_S = SimdReal(lj_ewaldcoeff2);
316 lje_c6_6_S = SimdReal(lj_ewaldcoeff6_6);
318 /* Determine the grid potential at the cut-off */
319 SimdReal lje_vc_S(ic->sh_lj_ewald);
323 /* The kernel either supports rcoulomb = rvdw or rcoulomb >= rvdw */
324 rc2_S = SimdReal(ic->rcoulomb*ic->rcoulomb);
325 #ifdef VDW_CUTOFF_CHECK
326 rcvdw2_S = SimdReal(ic->rvdw*ic->rvdw);
329 minRsq_S = SimdReal(NBNXN_MIN_RSQ);
333 shiftvec = shift_vec[0];
337 alignas(GMX_SIMD_ALIGNMENT) real pvdw_c6[2*UNROLLI*UNROLLJ];
338 real *pvdw_c12 = pvdw_c6 + UNROLLI*UNROLLJ;
340 for (int jp = 0; jp < UNROLLJ; jp++)
342 pvdw_c6 [0*UNROLLJ+jp] = nbat->nbfp[0*2];
343 pvdw_c6 [1*UNROLLJ+jp] = nbat->nbfp[0*2];
344 pvdw_c6 [2*UNROLLJ+jp] = nbat->nbfp[0*2];
345 pvdw_c6 [3*UNROLLJ+jp] = nbat->nbfp[0*2];
347 pvdw_c12[0*UNROLLJ+jp] = nbat->nbfp[0*2+1];
348 pvdw_c12[1*UNROLLJ+jp] = nbat->nbfp[0*2+1];
349 pvdw_c12[2*UNROLLJ+jp] = nbat->nbfp[0*2+1];
350 pvdw_c12[3*UNROLLJ+jp] = nbat->nbfp[0*2+1];
352 SimdReal c6_S0 = load<SimdReal>(pvdw_c6 +0*UNROLLJ);
353 SimdReal c6_S1 = load<SimdReal>(pvdw_c6 +1*UNROLLJ);
354 SimdReal c6_S2 = load<SimdReal>(pvdw_c6 +2*UNROLLJ);
355 SimdReal c6_S3 = load<SimdReal>(pvdw_c6 +3*UNROLLJ);
357 SimdReal c12_S0 = load<SimdReal>(pvdw_c12+0*UNROLLJ);
358 SimdReal c12_S1 = load<SimdReal>(pvdw_c12+1*UNROLLJ);
359 SimdReal c12_S2 = load<SimdReal>(pvdw_c12+2*UNROLLJ);
360 SimdReal c12_S3 = load<SimdReal>(pvdw_c12+3*UNROLLJ);
361 #endif /* FIX_LJ_C */
364 egps_ishift = nbat->neg_2log;
365 egps_imask = (1<<egps_ishift) - 1;
366 egps_jshift = 2*nbat->neg_2log;
367 egps_jmask = (1<<egps_jshift) - 1;
368 egps_jstride = (UNROLLJ>>1)*UNROLLJ;
369 /* Major division is over i-particle energy groups, determine the stride */
370 Vstride_i = nbat->nenergrp*(1<<nbat->neg_2log)*egps_jstride;
377 for (n = 0; n < nbl->nci; n++)
381 ish = (nbln->shift & NBNXN_CI_SHIFT);
383 cjind0 = nbln->cj_ind_start;
384 cjind1 = nbln->cj_ind_end;
386 ci_sh = (ish == CENTRAL ? ci : -1);
388 shX_S = SimdReal(shiftvec[ish3]);
389 shY_S = SimdReal(shiftvec[ish3+1]);
390 shZ_S = SimdReal(shiftvec[ish3+2]);
395 #if defined LJ_COMB_LB || defined LJ_COMB_GEOM || defined LJ_EWALD_GEOM
399 int sci = (ci>>1)*STRIDE;
400 int scix = sci*DIM + (ci & 1)*(STRIDE>>1);
401 #if defined LJ_COMB_LB || defined LJ_COMB_GEOM || defined LJ_EWALD_GEOM
402 int sci2 = sci*2 + (ci & 1)*(STRIDE>>1);
404 sci += (ci & 1)*(STRIDE>>1);
407 /* We have 5 LJ/C combinations, but use only three inner loops,
408 * as the other combinations are unlikely and/or not much faster:
409 * inner half-LJ + C for half-LJ + C / no-LJ + C
410 * inner LJ + C for full-LJ + C
411 * inner LJ for full-LJ + no-C / half-LJ + no-C
413 do_LJ = (nbln->shift & NBNXN_CI_DO_LJ(0));
414 do_coul = (nbln->shift & NBNXN_CI_DO_COUL(0));
415 half_LJ = ((nbln->shift & NBNXN_CI_HALF_LJ(0)) || !do_LJ) && do_coul;
418 egps_i = nbat->energrp[ci];
422 for (ia = 0; ia < UNROLLI; ia++)
424 egp_ia = (egps_i >> (ia*egps_ishift)) & egps_imask;
425 vvdwtp[ia] = Vvdw + egp_ia*Vstride_i;
426 vctp[ia] = Vc + egp_ia*Vstride_i;
433 gmx_bool do_self = TRUE;
435 gmx_bool do_self = do_coul;
438 if (do_self && l_cj[nbln->cj_ind_start].cj == ci_sh)
441 if (do_self && l_cj[nbln->cj_ind_start].cj == (ci_sh<<1))
444 if (do_self && l_cj[nbln->cj_ind_start].cj == (ci_sh>>1))
453 Vc_sub_self = 0.5*ic->c_rf;
457 Vc_sub_self = 0.5*tab_coul_F[2];
459 Vc_sub_self = 0.5*tab_coul_V[0];
462 #ifdef CALC_COUL_EWALD
464 Vc_sub_self = 0.5*ic->ewaldcoeff_q*M_2_SQRTPI;
467 for (ia = 0; ia < UNROLLI; ia++)
473 vctp[ia][((egps_i>>(ia*egps_ishift)) & egps_imask)*egps_jstride]
477 -= facel*qi*qi*Vc_sub_self;
485 for (ia = 0; ia < UNROLLI; ia++)
489 c6_i = nbat->nbfp[nbat->type[sci+ia]*(nbat->ntype + 1)*2]/6;
491 vvdwtp[ia][((egps_i>>(ia*egps_ishift)) & egps_imask)*egps_jstride]
495 += 0.5*c6_i*lj_ewaldcoeff6_6;
498 #endif /* LJ_EWALD_GEOM */
502 /* Load i atom data */
503 int sciy = scix + STRIDE;
504 int sciz = sciy + STRIDE;
505 ix_S0 = SimdReal(x[scix]) + shX_S;
506 ix_S1 = SimdReal(x[scix+1]) + shX_S;
507 ix_S2 = SimdReal(x[scix+2]) + shX_S;
508 ix_S3 = SimdReal(x[scix+3]) + shX_S;
509 iy_S0 = SimdReal(x[sciy]) + shY_S;
510 iy_S1 = SimdReal(x[sciy+1]) + shY_S;
511 iy_S2 = SimdReal(x[sciy+2]) + shY_S;
512 iy_S3 = SimdReal(x[sciy+3]) + shY_S;
513 iz_S0 = SimdReal(x[sciz]) + shZ_S;
514 iz_S1 = SimdReal(x[sciz+1]) + shZ_S;
515 iz_S2 = SimdReal(x[sciz+2]) + shZ_S;
516 iz_S3 = SimdReal(x[sciz+3]) + shZ_S;
520 iq_S0 = SimdReal(facel*q[sci]);
521 iq_S1 = SimdReal(facel*q[sci+1]);
522 iq_S2 = SimdReal(facel*q[sci+2]);
523 iq_S3 = SimdReal(facel*q[sci+3]);
527 hsig_i_S0 = SimdReal(ljc[sci2+0]);
528 hsig_i_S1 = SimdReal(ljc[sci2+1]);
529 hsig_i_S2 = SimdReal(ljc[sci2+2]);
530 hsig_i_S3 = SimdReal(ljc[sci2+3]);
531 seps_i_S0 = SimdReal(ljc[sci2+STRIDE+0]);
532 seps_i_S1 = SimdReal(ljc[sci2+STRIDE+1]);
533 seps_i_S2 = SimdReal(ljc[sci2+STRIDE+2]);
534 seps_i_S3 = SimdReal(ljc[sci2+STRIDE+3]);
537 SimdReal c6s_S0 = SimdReal(ljc[sci2+0]);
538 SimdReal c6s_S1 = SimdReal(ljc[sci2+1]);
539 SimdReal c6s_S2, c6s_S3;
542 c6s_S2 = SimdReal(ljc[sci2+2]);
543 c6s_S3 = SimdReal(ljc[sci2+3]);
550 SimdReal c12s_S0 = SimdReal(ljc[sci2+STRIDE+0]);
551 SimdReal c12s_S1 = SimdReal(ljc[sci2+STRIDE+1]);
552 SimdReal c12s_S2, c12s_S3;
555 c12s_S2 = SimdReal(ljc[sci2+STRIDE+2]);
556 c12s_S3 = SimdReal(ljc[sci2+STRIDE+3]);
564 const real *nbfp0 = nbfp_ptr + type[sci ]*nbat->ntype*c_simdBestPairAlignment;
565 const real *nbfp1 = nbfp_ptr + type[sci+1]*nbat->ntype*c_simdBestPairAlignment;
566 const real *nbfp2 = nullptr, *nbfp3 = nullptr;
569 nbfp2 = nbfp_ptr + type[sci+2]*nbat->ntype*c_simdBestPairAlignment;
570 nbfp3 = nbfp_ptr + type[sci+3]*nbat->ntype*c_simdBestPairAlignment;
575 /* We need the geometrically combined C6 for the PME grid correction */
576 SimdReal c6s_S0 = SimdReal(ljc[sci2+0]);
577 SimdReal c6s_S1 = SimdReal(ljc[sci2+1]);
578 SimdReal c6s_S2, c6s_S3;
581 c6s_S2 = SimdReal(ljc[sci2+2]);
582 c6s_S3 = SimdReal(ljc[sci2+3]);
586 /* Zero the potential energy for this list */
588 SimdReal Vvdwtot_S = setZero();
589 SimdReal vctot_S = setZero();
592 /* Clear i atom forces */
608 /* Currently all kernels use (at least half) LJ */
612 /* Coulomb: all i-atoms, LJ: first half i-atoms */
616 while (cjind < cjind1 && nbl->cj[cjind].excl != NBNXN_INTERACTION_MASK_ALL)
618 #include "gromacs/mdlib/nbnxn_kernels/simd_4xn/nbnxn_kernel_simd_4xn_inner.h"
622 for (; (cjind < cjind1); cjind++)
624 #include "gromacs/mdlib/nbnxn_kernels/simd_4xn/nbnxn_kernel_simd_4xn_inner.h"
631 /* Coulomb: all i-atoms, LJ: all i-atoms */
634 while (cjind < cjind1 && nbl->cj[cjind].excl != NBNXN_INTERACTION_MASK_ALL)
636 #include "gromacs/mdlib/nbnxn_kernels/simd_4xn/nbnxn_kernel_simd_4xn_inner.h"
640 for (; (cjind < cjind1); cjind++)
642 #include "gromacs/mdlib/nbnxn_kernels/simd_4xn/nbnxn_kernel_simd_4xn_inner.h"
648 /* Coulomb: none, LJ: all i-atoms */
650 while (cjind < cjind1 && nbl->cj[cjind].excl != NBNXN_INTERACTION_MASK_ALL)
652 #include "gromacs/mdlib/nbnxn_kernels/simd_4xn/nbnxn_kernel_simd_4xn_inner.h"
656 for (; (cjind < cjind1); cjind++)
658 #include "gromacs/mdlib/nbnxn_kernels/simd_4xn/nbnxn_kernel_simd_4xn_inner.h"
662 ninner += cjind1 - cjind0;
664 /* Add accumulated i-forces to the force array */
665 real fShiftX = reduceIncr4ReturnSum(f+scix, fix_S0, fix_S1, fix_S2, fix_S3);
666 real fShiftY = reduceIncr4ReturnSum(f+sciy, fiy_S0, fiy_S1, fiy_S2, fiy_S3);
667 real fShiftZ = reduceIncr4ReturnSum(f+sciz, fiz_S0, fiz_S1, fiz_S2, fiz_S3);
670 #ifdef CALC_SHIFTFORCES
671 fshift[ish3+0] += fShiftX;
672 fshift[ish3+1] += fShiftY;
673 fshift[ish3+2] += fShiftZ;
679 *Vc += reduce(vctot_S);
682 *Vvdw += reduce(Vvdwtot_S);
685 /* Outer loop uses 6 flops/iteration */
689 printf("atom pairs %d\n", npair);