1a0e658d223b5440b6b30fae8590212bdc6220a3
[alexxy/gromacs.git] / src / gromacs / gmxlib / nonbonded / nb_kernel_sse4_1_double / nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_sse4_1_double.c
1 /*
2  * This file is part of the GROMACS molecular simulation package.
3  *
4  * Copyright (c) 2012,2013,2014, 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  *
14  * GROMACS is distributed in the hope that it will be useful,
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17  * Lesser General Public License for more details.
18  *
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34  */
35 /*
36  * Note: this file was generated by the GROMACS sse4_1_double kernel generator.
37  */
38 #include "config.h"
39
40 #include <math.h>
41
42 #include "../nb_kernel.h"
43 #include "gromacs/legacyheaders/types/simple.h"
44 #include "gromacs/math/vec.h"
45 #include "gromacs/legacyheaders/nrnb.h"
46
47 #include "gromacs/simd/math_x86_sse4_1_double.h"
48 #include "kernelutil_x86_sse4_1_double.h"
49
50 /*
51  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_VF_sse4_1_double
52  * Electrostatics interaction: Ewald
53  * VdW interaction:            LJEwald
54  * Geometry:                   Particle-Particle
55  * Calculate force/pot:        PotentialAndForce
56  */
57 void
58 nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_VF_sse4_1_double
59                     (t_nblist                    * gmx_restrict       nlist,
60                      rvec                        * gmx_restrict          xx,
61                      rvec                        * gmx_restrict          ff,
62                      t_forcerec                  * gmx_restrict          fr,
63                      t_mdatoms                   * gmx_restrict     mdatoms,
64                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
65                      t_nrnb                      * gmx_restrict        nrnb)
66 {
67     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
68      * just 0 for non-waters.
69      * Suffixes A,B refer to j loop unrolling done with SSE double precision, e.g. for the two different
70      * jnr indices corresponding to data put in the four positions in the SIMD register.
71      */
72     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
73     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
74     int              jnrA,jnrB;
75     int              j_coord_offsetA,j_coord_offsetB;
76     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
77     real             rcutoff_scalar;
78     real             *shiftvec,*fshift,*x,*f;
79     __m128d          tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
80     int              vdwioffset0;
81     __m128d          ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
82     int              vdwjidx0A,vdwjidx0B;
83     __m128d          jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
84     __m128d          dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
85     __m128d          velec,felec,velecsum,facel,crf,krf,krf2;
86     real             *charge;
87     int              nvdwtype;
88     __m128d          rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
89     int              *vdwtype;
90     real             *vdwparam;
91     __m128d          one_sixth   = _mm_set1_pd(1.0/6.0);
92     __m128d          one_twelfth = _mm_set1_pd(1.0/12.0);
93     __m128d           c6grid_00;
94     __m128d           ewclj,ewclj2,ewclj6,ewcljrsq,poly,exponent,f6A,f6B,sh_lj_ewald;
95     real             *vdwgridparam;
96     __m128d           one_half = _mm_set1_pd(0.5);
97     __m128d           minus_one = _mm_set1_pd(-1.0);
98     __m128i          ewitab;
99     __m128d          ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace,ewtabF,ewtabFn,ewtabD,ewtabV;
100     real             *ewtab;
101     __m128d          dummy_mask,cutoff_mask;
102     __m128d          signbit   = gmx_mm_castsi128_pd( _mm_set_epi32(0x80000000,0x00000000,0x80000000,0x00000000) );
103     __m128d          one     = _mm_set1_pd(1.0);
104     __m128d          two     = _mm_set1_pd(2.0);
105     x                = xx[0];
106     f                = ff[0];
107
108     nri              = nlist->nri;
109     iinr             = nlist->iinr;
110     jindex           = nlist->jindex;
111     jjnr             = nlist->jjnr;
112     shiftidx         = nlist->shift;
113     gid              = nlist->gid;
114     shiftvec         = fr->shift_vec[0];
115     fshift           = fr->fshift[0];
116     facel            = _mm_set1_pd(fr->epsfac);
117     charge           = mdatoms->chargeA;
118     nvdwtype         = fr->ntype;
119     vdwparam         = fr->nbfp;
120     vdwtype          = mdatoms->typeA;
121     vdwgridparam     = fr->ljpme_c6grid;
122     sh_lj_ewald      = _mm_set1_pd(fr->ic->sh_lj_ewald);
123     ewclj            = _mm_set1_pd(fr->ewaldcoeff_lj);
124     ewclj2           = _mm_mul_pd(minus_one,_mm_mul_pd(ewclj,ewclj));
125
126     sh_ewald         = _mm_set1_pd(fr->ic->sh_ewald);
127     ewtab            = fr->ic->tabq_coul_FDV0;
128     ewtabscale       = _mm_set1_pd(fr->ic->tabq_scale);
129     ewtabhalfspace   = _mm_set1_pd(0.5/fr->ic->tabq_scale);
130
131     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
132     rcutoff_scalar   = fr->rcoulomb;
133     rcutoff          = _mm_set1_pd(rcutoff_scalar);
134     rcutoff2         = _mm_mul_pd(rcutoff,rcutoff);
135
136     sh_vdw_invrcut6  = _mm_set1_pd(fr->ic->sh_invrc6);
137     rvdw             = _mm_set1_pd(fr->rvdw);
138
139     /* Avoid stupid compiler warnings */
140     jnrA = jnrB = 0;
141     j_coord_offsetA = 0;
142     j_coord_offsetB = 0;
143
144     outeriter        = 0;
145     inneriter        = 0;
146
147     /* Start outer loop over neighborlists */
148     for(iidx=0; iidx<nri; iidx++)
149     {
150         /* Load shift vector for this list */
151         i_shift_offset   = DIM*shiftidx[iidx];
152
153         /* Load limits for loop over neighbors */
154         j_index_start    = jindex[iidx];
155         j_index_end      = jindex[iidx+1];
156
157         /* Get outer coordinate index */
158         inr              = iinr[iidx];
159         i_coord_offset   = DIM*inr;
160
161         /* Load i particle coords and add shift vector */
162         gmx_mm_load_shift_and_1rvec_broadcast_pd(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
163
164         fix0             = _mm_setzero_pd();
165         fiy0             = _mm_setzero_pd();
166         fiz0             = _mm_setzero_pd();
167
168         /* Load parameters for i particles */
169         iq0              = _mm_mul_pd(facel,_mm_load1_pd(charge+inr+0));
170         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
171
172         /* Reset potential sums */
173         velecsum         = _mm_setzero_pd();
174         vvdwsum          = _mm_setzero_pd();
175
176         /* Start inner kernel loop */
177         for(jidx=j_index_start; jidx<j_index_end-1; jidx+=2)
178         {
179
180             /* Get j neighbor index, and coordinate index */
181             jnrA             = jjnr[jidx];
182             jnrB             = jjnr[jidx+1];
183             j_coord_offsetA  = DIM*jnrA;
184             j_coord_offsetB  = DIM*jnrB;
185
186             /* load j atom coordinates */
187             gmx_mm_load_1rvec_2ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
188                                               &jx0,&jy0,&jz0);
189
190             /* Calculate displacement vector */
191             dx00             = _mm_sub_pd(ix0,jx0);
192             dy00             = _mm_sub_pd(iy0,jy0);
193             dz00             = _mm_sub_pd(iz0,jz0);
194
195             /* Calculate squared distance and things based on it */
196             rsq00            = gmx_mm_calc_rsq_pd(dx00,dy00,dz00);
197
198             rinv00           = gmx_mm_invsqrt_pd(rsq00);
199
200             rinvsq00         = _mm_mul_pd(rinv00,rinv00);
201
202             /* Load parameters for j particles */
203             jq0              = gmx_mm_load_2real_swizzle_pd(charge+jnrA+0,charge+jnrB+0);
204             vdwjidx0A        = 2*vdwtype[jnrA+0];
205             vdwjidx0B        = 2*vdwtype[jnrB+0];
206
207             /**************************
208              * CALCULATE INTERACTIONS *
209              **************************/
210
211             if (gmx_mm_any_lt(rsq00,rcutoff2))
212             {
213
214             r00              = _mm_mul_pd(rsq00,rinv00);
215
216             /* Compute parameters for interactions between i and j atoms */
217             qq00             = _mm_mul_pd(iq0,jq0);
218             gmx_mm_load_2pair_swizzle_pd(vdwparam+vdwioffset0+vdwjidx0A,
219                                          vdwparam+vdwioffset0+vdwjidx0B,&c6_00,&c12_00);
220             c6grid_00       = gmx_mm_load_2real_swizzle_pd(vdwgridparam+vdwioffset0+vdwjidx0A,
221                                                                vdwgridparam+vdwioffset0+vdwjidx0B);
222
223             /* EWALD ELECTROSTATICS */
224
225             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
226             ewrt             = _mm_mul_pd(r00,ewtabscale);
227             ewitab           = _mm_cvttpd_epi32(ewrt);
228             eweps            = _mm_sub_pd(ewrt,_mm_round_pd(ewrt, _MM_FROUND_FLOOR));
229             ewitab           = _mm_slli_epi32(ewitab,2);
230             ewtabF           = _mm_load_pd( ewtab + gmx_mm_extract_epi32(ewitab,0) );
231             ewtabD           = _mm_load_pd( ewtab + gmx_mm_extract_epi32(ewitab,1) );
232             GMX_MM_TRANSPOSE2_PD(ewtabF,ewtabD);
233             ewtabV           = _mm_load_sd( ewtab + gmx_mm_extract_epi32(ewitab,0) +2);
234             ewtabFn          = _mm_load_sd( ewtab + gmx_mm_extract_epi32(ewitab,1) +2);
235             GMX_MM_TRANSPOSE2_PD(ewtabV,ewtabFn);
236             felec            = _mm_add_pd(ewtabF,_mm_mul_pd(eweps,ewtabD));
237             velec            = _mm_sub_pd(ewtabV,_mm_mul_pd(_mm_mul_pd(ewtabhalfspace,eweps),_mm_add_pd(ewtabF,felec)));
238             velec            = _mm_mul_pd(qq00,_mm_sub_pd(_mm_sub_pd(rinv00,sh_ewald),velec));
239             felec            = _mm_mul_pd(_mm_mul_pd(qq00,rinv00),_mm_sub_pd(rinvsq00,felec));
240
241             /* Analytical LJ-PME */
242             rinvsix          = _mm_mul_pd(_mm_mul_pd(rinvsq00,rinvsq00),rinvsq00);
243             ewcljrsq         = _mm_mul_pd(ewclj2,rsq00);
244             ewclj6           = _mm_mul_pd(ewclj2,_mm_mul_pd(ewclj2,ewclj2));
245             exponent         = gmx_simd_exp_d(ewcljrsq);
246             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
247             poly             = _mm_mul_pd(exponent,_mm_add_pd(_mm_sub_pd(one,ewcljrsq),_mm_mul_pd(_mm_mul_pd(ewcljrsq,ewcljrsq),one_half)));
248             /* vvdw6 = [C6 - C6grid * (1-poly)]/r6 */
249             vvdw6            = _mm_mul_pd(_mm_sub_pd(c6_00,_mm_mul_pd(c6grid_00,_mm_sub_pd(one,poly))),rinvsix);
250             vvdw12           = _mm_mul_pd(c12_00,_mm_mul_pd(rinvsix,rinvsix));
251             vvdw             = _mm_sub_pd(_mm_mul_pd( _mm_sub_pd(vvdw12 , _mm_mul_pd(c12_00,_mm_mul_pd(sh_vdw_invrcut6,sh_vdw_invrcut6))),one_twelfth),
252                                _mm_mul_pd( _mm_sub_pd(vvdw6,_mm_add_pd(_mm_mul_pd(c6_00,sh_vdw_invrcut6),_mm_mul_pd(c6grid_00,sh_lj_ewald))),one_sixth));
253             /* fvdw = vvdw12/r - (vvdw6/r + (C6grid * exponent * beta^6)/r) */
254             fvdw             = _mm_mul_pd(_mm_sub_pd(vvdw12,_mm_sub_pd(vvdw6,_mm_mul_pd(_mm_mul_pd(c6grid_00,one_sixth),_mm_mul_pd(exponent,ewclj6)))),rinvsq00);
255
256             cutoff_mask      = _mm_cmplt_pd(rsq00,rcutoff2);
257
258             /* Update potential sum for this i atom from the interaction with this j atom. */
259             velec            = _mm_and_pd(velec,cutoff_mask);
260             velecsum         = _mm_add_pd(velecsum,velec);
261             vvdw             = _mm_and_pd(vvdw,cutoff_mask);
262             vvdwsum          = _mm_add_pd(vvdwsum,vvdw);
263
264             fscal            = _mm_add_pd(felec,fvdw);
265
266             fscal            = _mm_and_pd(fscal,cutoff_mask);
267
268             /* Calculate temporary vectorial force */
269             tx               = _mm_mul_pd(fscal,dx00);
270             ty               = _mm_mul_pd(fscal,dy00);
271             tz               = _mm_mul_pd(fscal,dz00);
272
273             /* Update vectorial force */
274             fix0             = _mm_add_pd(fix0,tx);
275             fiy0             = _mm_add_pd(fiy0,ty);
276             fiz0             = _mm_add_pd(fiz0,tz);
277
278             gmx_mm_decrement_1rvec_2ptr_swizzle_pd(f+j_coord_offsetA,f+j_coord_offsetB,tx,ty,tz);
279
280             }
281
282             /* Inner loop uses 81 flops */
283         }
284
285         if(jidx<j_index_end)
286         {
287
288             jnrA             = jjnr[jidx];
289             j_coord_offsetA  = DIM*jnrA;
290
291             /* load j atom coordinates */
292             gmx_mm_load_1rvec_1ptr_swizzle_pd(x+j_coord_offsetA,
293                                               &jx0,&jy0,&jz0);
294
295             /* Calculate displacement vector */
296             dx00             = _mm_sub_pd(ix0,jx0);
297             dy00             = _mm_sub_pd(iy0,jy0);
298             dz00             = _mm_sub_pd(iz0,jz0);
299
300             /* Calculate squared distance and things based on it */
301             rsq00            = gmx_mm_calc_rsq_pd(dx00,dy00,dz00);
302
303             rinv00           = gmx_mm_invsqrt_pd(rsq00);
304
305             rinvsq00         = _mm_mul_pd(rinv00,rinv00);
306
307             /* Load parameters for j particles */
308             jq0              = _mm_load_sd(charge+jnrA+0);
309             vdwjidx0A        = 2*vdwtype[jnrA+0];
310
311             /**************************
312              * CALCULATE INTERACTIONS *
313              **************************/
314
315             if (gmx_mm_any_lt(rsq00,rcutoff2))
316             {
317
318             r00              = _mm_mul_pd(rsq00,rinv00);
319
320             /* Compute parameters for interactions between i and j atoms */
321             qq00             = _mm_mul_pd(iq0,jq0);
322             gmx_mm_load_1pair_swizzle_pd(vdwparam+vdwioffset0+vdwjidx0A,&c6_00,&c12_00);
323
324             c6grid_00       = gmx_mm_load_1real_pd(vdwgridparam+vdwioffset0+vdwjidx0A);
325
326             /* EWALD ELECTROSTATICS */
327
328             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
329             ewrt             = _mm_mul_pd(r00,ewtabscale);
330             ewitab           = _mm_cvttpd_epi32(ewrt);
331             eweps            = _mm_sub_pd(ewrt,_mm_round_pd(ewrt, _MM_FROUND_FLOOR));
332             ewitab           = _mm_slli_epi32(ewitab,2);
333             ewtabF           = _mm_load_pd( ewtab + gmx_mm_extract_epi32(ewitab,0) );
334             ewtabD           = _mm_setzero_pd();
335             GMX_MM_TRANSPOSE2_PD(ewtabF,ewtabD);
336             ewtabV           = _mm_load_sd( ewtab + gmx_mm_extract_epi32(ewitab,0) +2);
337             ewtabFn          = _mm_setzero_pd();
338             GMX_MM_TRANSPOSE2_PD(ewtabV,ewtabFn);
339             felec            = _mm_add_pd(ewtabF,_mm_mul_pd(eweps,ewtabD));
340             velec            = _mm_sub_pd(ewtabV,_mm_mul_pd(_mm_mul_pd(ewtabhalfspace,eweps),_mm_add_pd(ewtabF,felec)));
341             velec            = _mm_mul_pd(qq00,_mm_sub_pd(_mm_sub_pd(rinv00,sh_ewald),velec));
342             felec            = _mm_mul_pd(_mm_mul_pd(qq00,rinv00),_mm_sub_pd(rinvsq00,felec));
343
344             /* Analytical LJ-PME */
345             rinvsix          = _mm_mul_pd(_mm_mul_pd(rinvsq00,rinvsq00),rinvsq00);
346             ewcljrsq         = _mm_mul_pd(ewclj2,rsq00);
347             ewclj6           = _mm_mul_pd(ewclj2,_mm_mul_pd(ewclj2,ewclj2));
348             exponent         = gmx_simd_exp_d(ewcljrsq);
349             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
350             poly             = _mm_mul_pd(exponent,_mm_add_pd(_mm_sub_pd(one,ewcljrsq),_mm_mul_pd(_mm_mul_pd(ewcljrsq,ewcljrsq),one_half)));
351             /* vvdw6 = [C6 - C6grid * (1-poly)]/r6 */
352             vvdw6            = _mm_mul_pd(_mm_sub_pd(c6_00,_mm_mul_pd(c6grid_00,_mm_sub_pd(one,poly))),rinvsix);
353             vvdw12           = _mm_mul_pd(c12_00,_mm_mul_pd(rinvsix,rinvsix));
354             vvdw             = _mm_sub_pd(_mm_mul_pd( _mm_sub_pd(vvdw12 , _mm_mul_pd(c12_00,_mm_mul_pd(sh_vdw_invrcut6,sh_vdw_invrcut6))),one_twelfth),
355                                _mm_mul_pd( _mm_sub_pd(vvdw6,_mm_add_pd(_mm_mul_pd(c6_00,sh_vdw_invrcut6),_mm_mul_pd(c6grid_00,sh_lj_ewald))),one_sixth));
356             /* fvdw = vvdw12/r - (vvdw6/r + (C6grid * exponent * beta^6)/r) */
357             fvdw             = _mm_mul_pd(_mm_sub_pd(vvdw12,_mm_sub_pd(vvdw6,_mm_mul_pd(_mm_mul_pd(c6grid_00,one_sixth),_mm_mul_pd(exponent,ewclj6)))),rinvsq00);
358
359             cutoff_mask      = _mm_cmplt_pd(rsq00,rcutoff2);
360
361             /* Update potential sum for this i atom from the interaction with this j atom. */
362             velec            = _mm_and_pd(velec,cutoff_mask);
363             velec            = _mm_unpacklo_pd(velec,_mm_setzero_pd());
364             velecsum         = _mm_add_pd(velecsum,velec);
365             vvdw             = _mm_and_pd(vvdw,cutoff_mask);
366             vvdw             = _mm_unpacklo_pd(vvdw,_mm_setzero_pd());
367             vvdwsum          = _mm_add_pd(vvdwsum,vvdw);
368
369             fscal            = _mm_add_pd(felec,fvdw);
370
371             fscal            = _mm_and_pd(fscal,cutoff_mask);
372
373             fscal            = _mm_unpacklo_pd(fscal,_mm_setzero_pd());
374
375             /* Calculate temporary vectorial force */
376             tx               = _mm_mul_pd(fscal,dx00);
377             ty               = _mm_mul_pd(fscal,dy00);
378             tz               = _mm_mul_pd(fscal,dz00);
379
380             /* Update vectorial force */
381             fix0             = _mm_add_pd(fix0,tx);
382             fiy0             = _mm_add_pd(fiy0,ty);
383             fiz0             = _mm_add_pd(fiz0,tz);
384
385             gmx_mm_decrement_1rvec_1ptr_swizzle_pd(f+j_coord_offsetA,tx,ty,tz);
386
387             }
388
389             /* Inner loop uses 81 flops */
390         }
391
392         /* End of innermost loop */
393
394         gmx_mm_update_iforce_1atom_swizzle_pd(fix0,fiy0,fiz0,
395                                               f+i_coord_offset,fshift+i_shift_offset);
396
397         ggid                        = gid[iidx];
398         /* Update potential energies */
399         gmx_mm_update_1pot_pd(velecsum,kernel_data->energygrp_elec+ggid);
400         gmx_mm_update_1pot_pd(vvdwsum,kernel_data->energygrp_vdw+ggid);
401
402         /* Increment number of inner iterations */
403         inneriter                  += j_index_end - j_index_start;
404
405         /* Outer loop uses 9 flops */
406     }
407
408     /* Increment number of outer iterations */
409     outeriter        += nri;
410
411     /* Update outer/inner flops */
412
413     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_VF,outeriter*9 + inneriter*81);
414 }
415 /*
416  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_F_sse4_1_double
417  * Electrostatics interaction: Ewald
418  * VdW interaction:            LJEwald
419  * Geometry:                   Particle-Particle
420  * Calculate force/pot:        Force
421  */
422 void
423 nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_F_sse4_1_double
424                     (t_nblist                    * gmx_restrict       nlist,
425                      rvec                        * gmx_restrict          xx,
426                      rvec                        * gmx_restrict          ff,
427                      t_forcerec                  * gmx_restrict          fr,
428                      t_mdatoms                   * gmx_restrict     mdatoms,
429                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
430                      t_nrnb                      * gmx_restrict        nrnb)
431 {
432     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
433      * just 0 for non-waters.
434      * Suffixes A,B refer to j loop unrolling done with SSE double precision, e.g. for the two different
435      * jnr indices corresponding to data put in the four positions in the SIMD register.
436      */
437     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
438     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
439     int              jnrA,jnrB;
440     int              j_coord_offsetA,j_coord_offsetB;
441     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
442     real             rcutoff_scalar;
443     real             *shiftvec,*fshift,*x,*f;
444     __m128d          tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
445     int              vdwioffset0;
446     __m128d          ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
447     int              vdwjidx0A,vdwjidx0B;
448     __m128d          jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
449     __m128d          dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
450     __m128d          velec,felec,velecsum,facel,crf,krf,krf2;
451     real             *charge;
452     int              nvdwtype;
453     __m128d          rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
454     int              *vdwtype;
455     real             *vdwparam;
456     __m128d          one_sixth   = _mm_set1_pd(1.0/6.0);
457     __m128d          one_twelfth = _mm_set1_pd(1.0/12.0);
458     __m128d           c6grid_00;
459     __m128d           ewclj,ewclj2,ewclj6,ewcljrsq,poly,exponent,f6A,f6B,sh_lj_ewald;
460     real             *vdwgridparam;
461     __m128d           one_half = _mm_set1_pd(0.5);
462     __m128d           minus_one = _mm_set1_pd(-1.0);
463     __m128i          ewitab;
464     __m128d          ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace,ewtabF,ewtabFn,ewtabD,ewtabV;
465     real             *ewtab;
466     __m128d          dummy_mask,cutoff_mask;
467     __m128d          signbit   = gmx_mm_castsi128_pd( _mm_set_epi32(0x80000000,0x00000000,0x80000000,0x00000000) );
468     __m128d          one     = _mm_set1_pd(1.0);
469     __m128d          two     = _mm_set1_pd(2.0);
470     x                = xx[0];
471     f                = ff[0];
472
473     nri              = nlist->nri;
474     iinr             = nlist->iinr;
475     jindex           = nlist->jindex;
476     jjnr             = nlist->jjnr;
477     shiftidx         = nlist->shift;
478     gid              = nlist->gid;
479     shiftvec         = fr->shift_vec[0];
480     fshift           = fr->fshift[0];
481     facel            = _mm_set1_pd(fr->epsfac);
482     charge           = mdatoms->chargeA;
483     nvdwtype         = fr->ntype;
484     vdwparam         = fr->nbfp;
485     vdwtype          = mdatoms->typeA;
486     vdwgridparam     = fr->ljpme_c6grid;
487     sh_lj_ewald      = _mm_set1_pd(fr->ic->sh_lj_ewald);
488     ewclj            = _mm_set1_pd(fr->ewaldcoeff_lj);
489     ewclj2           = _mm_mul_pd(minus_one,_mm_mul_pd(ewclj,ewclj));
490
491     sh_ewald         = _mm_set1_pd(fr->ic->sh_ewald);
492     ewtab            = fr->ic->tabq_coul_F;
493     ewtabscale       = _mm_set1_pd(fr->ic->tabq_scale);
494     ewtabhalfspace   = _mm_set1_pd(0.5/fr->ic->tabq_scale);
495
496     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
497     rcutoff_scalar   = fr->rcoulomb;
498     rcutoff          = _mm_set1_pd(rcutoff_scalar);
499     rcutoff2         = _mm_mul_pd(rcutoff,rcutoff);
500
501     sh_vdw_invrcut6  = _mm_set1_pd(fr->ic->sh_invrc6);
502     rvdw             = _mm_set1_pd(fr->rvdw);
503
504     /* Avoid stupid compiler warnings */
505     jnrA = jnrB = 0;
506     j_coord_offsetA = 0;
507     j_coord_offsetB = 0;
508
509     outeriter        = 0;
510     inneriter        = 0;
511
512     /* Start outer loop over neighborlists */
513     for(iidx=0; iidx<nri; iidx++)
514     {
515         /* Load shift vector for this list */
516         i_shift_offset   = DIM*shiftidx[iidx];
517
518         /* Load limits for loop over neighbors */
519         j_index_start    = jindex[iidx];
520         j_index_end      = jindex[iidx+1];
521
522         /* Get outer coordinate index */
523         inr              = iinr[iidx];
524         i_coord_offset   = DIM*inr;
525
526         /* Load i particle coords and add shift vector */
527         gmx_mm_load_shift_and_1rvec_broadcast_pd(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
528
529         fix0             = _mm_setzero_pd();
530         fiy0             = _mm_setzero_pd();
531         fiz0             = _mm_setzero_pd();
532
533         /* Load parameters for i particles */
534         iq0              = _mm_mul_pd(facel,_mm_load1_pd(charge+inr+0));
535         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
536
537         /* Start inner kernel loop */
538         for(jidx=j_index_start; jidx<j_index_end-1; jidx+=2)
539         {
540
541             /* Get j neighbor index, and coordinate index */
542             jnrA             = jjnr[jidx];
543             jnrB             = jjnr[jidx+1];
544             j_coord_offsetA  = DIM*jnrA;
545             j_coord_offsetB  = DIM*jnrB;
546
547             /* load j atom coordinates */
548             gmx_mm_load_1rvec_2ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
549                                               &jx0,&jy0,&jz0);
550
551             /* Calculate displacement vector */
552             dx00             = _mm_sub_pd(ix0,jx0);
553             dy00             = _mm_sub_pd(iy0,jy0);
554             dz00             = _mm_sub_pd(iz0,jz0);
555
556             /* Calculate squared distance and things based on it */
557             rsq00            = gmx_mm_calc_rsq_pd(dx00,dy00,dz00);
558
559             rinv00           = gmx_mm_invsqrt_pd(rsq00);
560
561             rinvsq00         = _mm_mul_pd(rinv00,rinv00);
562
563             /* Load parameters for j particles */
564             jq0              = gmx_mm_load_2real_swizzle_pd(charge+jnrA+0,charge+jnrB+0);
565             vdwjidx0A        = 2*vdwtype[jnrA+0];
566             vdwjidx0B        = 2*vdwtype[jnrB+0];
567
568             /**************************
569              * CALCULATE INTERACTIONS *
570              **************************/
571
572             if (gmx_mm_any_lt(rsq00,rcutoff2))
573             {
574
575             r00              = _mm_mul_pd(rsq00,rinv00);
576
577             /* Compute parameters for interactions between i and j atoms */
578             qq00             = _mm_mul_pd(iq0,jq0);
579             gmx_mm_load_2pair_swizzle_pd(vdwparam+vdwioffset0+vdwjidx0A,
580                                          vdwparam+vdwioffset0+vdwjidx0B,&c6_00,&c12_00);
581             c6grid_00       = gmx_mm_load_2real_swizzle_pd(vdwgridparam+vdwioffset0+vdwjidx0A,
582                                                                vdwgridparam+vdwioffset0+vdwjidx0B);
583
584             /* EWALD ELECTROSTATICS */
585
586             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
587             ewrt             = _mm_mul_pd(r00,ewtabscale);
588             ewitab           = _mm_cvttpd_epi32(ewrt);
589             eweps            = _mm_sub_pd(ewrt,_mm_round_pd(ewrt, _MM_FROUND_FLOOR));
590             gmx_mm_load_2pair_swizzle_pd(ewtab+gmx_mm_extract_epi32(ewitab,0),ewtab+gmx_mm_extract_epi32(ewitab,1),
591                                          &ewtabF,&ewtabFn);
592             felec            = _mm_add_pd(_mm_mul_pd( _mm_sub_pd(one,eweps),ewtabF),_mm_mul_pd(eweps,ewtabFn));
593             felec            = _mm_mul_pd(_mm_mul_pd(qq00,rinv00),_mm_sub_pd(rinvsq00,felec));
594
595             /* Analytical LJ-PME */
596             rinvsix          = _mm_mul_pd(_mm_mul_pd(rinvsq00,rinvsq00),rinvsq00);
597             ewcljrsq         = _mm_mul_pd(ewclj2,rsq00);
598             ewclj6           = _mm_mul_pd(ewclj2,_mm_mul_pd(ewclj2,ewclj2));
599             exponent         = gmx_simd_exp_d(ewcljrsq);
600             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
601             poly             = _mm_mul_pd(exponent,_mm_add_pd(_mm_sub_pd(one,ewcljrsq),_mm_mul_pd(_mm_mul_pd(ewcljrsq,ewcljrsq),one_half)));
602             /* f6A = 6 * C6grid * (1 - poly) */
603             f6A              = _mm_mul_pd(c6grid_00,_mm_sub_pd(one,poly));
604             /* f6B = C6grid * exponent * beta^6 */
605             f6B              = _mm_mul_pd(_mm_mul_pd(c6grid_00,one_sixth),_mm_mul_pd(exponent,ewclj6));
606             /* fvdw = 12*C12/r13 - ((6*C6 - f6A)/r6 + f6B)/r */
607             fvdw              = _mm_mul_pd(_mm_add_pd(_mm_mul_pd(_mm_sub_pd(_mm_mul_pd(c12_00,rinvsix),_mm_sub_pd(c6_00,f6A)),rinvsix),f6B),rinvsq00);
608
609             cutoff_mask      = _mm_cmplt_pd(rsq00,rcutoff2);
610
611             fscal            = _mm_add_pd(felec,fvdw);
612
613             fscal            = _mm_and_pd(fscal,cutoff_mask);
614
615             /* Calculate temporary vectorial force */
616             tx               = _mm_mul_pd(fscal,dx00);
617             ty               = _mm_mul_pd(fscal,dy00);
618             tz               = _mm_mul_pd(fscal,dz00);
619
620             /* Update vectorial force */
621             fix0             = _mm_add_pd(fix0,tx);
622             fiy0             = _mm_add_pd(fiy0,ty);
623             fiz0             = _mm_add_pd(fiz0,tz);
624
625             gmx_mm_decrement_1rvec_2ptr_swizzle_pd(f+j_coord_offsetA,f+j_coord_offsetB,tx,ty,tz);
626
627             }
628
629             /* Inner loop uses 62 flops */
630         }
631
632         if(jidx<j_index_end)
633         {
634
635             jnrA             = jjnr[jidx];
636             j_coord_offsetA  = DIM*jnrA;
637
638             /* load j atom coordinates */
639             gmx_mm_load_1rvec_1ptr_swizzle_pd(x+j_coord_offsetA,
640                                               &jx0,&jy0,&jz0);
641
642             /* Calculate displacement vector */
643             dx00             = _mm_sub_pd(ix0,jx0);
644             dy00             = _mm_sub_pd(iy0,jy0);
645             dz00             = _mm_sub_pd(iz0,jz0);
646
647             /* Calculate squared distance and things based on it */
648             rsq00            = gmx_mm_calc_rsq_pd(dx00,dy00,dz00);
649
650             rinv00           = gmx_mm_invsqrt_pd(rsq00);
651
652             rinvsq00         = _mm_mul_pd(rinv00,rinv00);
653
654             /* Load parameters for j particles */
655             jq0              = _mm_load_sd(charge+jnrA+0);
656             vdwjidx0A        = 2*vdwtype[jnrA+0];
657
658             /**************************
659              * CALCULATE INTERACTIONS *
660              **************************/
661
662             if (gmx_mm_any_lt(rsq00,rcutoff2))
663             {
664
665             r00              = _mm_mul_pd(rsq00,rinv00);
666
667             /* Compute parameters for interactions between i and j atoms */
668             qq00             = _mm_mul_pd(iq0,jq0);
669             gmx_mm_load_1pair_swizzle_pd(vdwparam+vdwioffset0+vdwjidx0A,&c6_00,&c12_00);
670
671             c6grid_00       = gmx_mm_load_1real_pd(vdwgridparam+vdwioffset0+vdwjidx0A);
672
673             /* EWALD ELECTROSTATICS */
674
675             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
676             ewrt             = _mm_mul_pd(r00,ewtabscale);
677             ewitab           = _mm_cvttpd_epi32(ewrt);
678             eweps            = _mm_sub_pd(ewrt,_mm_round_pd(ewrt, _MM_FROUND_FLOOR));
679             gmx_mm_load_1pair_swizzle_pd(ewtab+gmx_mm_extract_epi32(ewitab,0),&ewtabF,&ewtabFn);
680             felec            = _mm_add_pd(_mm_mul_pd( _mm_sub_pd(one,eweps),ewtabF),_mm_mul_pd(eweps,ewtabFn));
681             felec            = _mm_mul_pd(_mm_mul_pd(qq00,rinv00),_mm_sub_pd(rinvsq00,felec));
682
683             /* Analytical LJ-PME */
684             rinvsix          = _mm_mul_pd(_mm_mul_pd(rinvsq00,rinvsq00),rinvsq00);
685             ewcljrsq         = _mm_mul_pd(ewclj2,rsq00);
686             ewclj6           = _mm_mul_pd(ewclj2,_mm_mul_pd(ewclj2,ewclj2));
687             exponent         = gmx_simd_exp_d(ewcljrsq);
688             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
689             poly             = _mm_mul_pd(exponent,_mm_add_pd(_mm_sub_pd(one,ewcljrsq),_mm_mul_pd(_mm_mul_pd(ewcljrsq,ewcljrsq),one_half)));
690             /* f6A = 6 * C6grid * (1 - poly) */
691             f6A              = _mm_mul_pd(c6grid_00,_mm_sub_pd(one,poly));
692             /* f6B = C6grid * exponent * beta^6 */
693             f6B              = _mm_mul_pd(_mm_mul_pd(c6grid_00,one_sixth),_mm_mul_pd(exponent,ewclj6));
694             /* fvdw = 12*C12/r13 - ((6*C6 - f6A)/r6 + f6B)/r */
695             fvdw              = _mm_mul_pd(_mm_add_pd(_mm_mul_pd(_mm_sub_pd(_mm_mul_pd(c12_00,rinvsix),_mm_sub_pd(c6_00,f6A)),rinvsix),f6B),rinvsq00);
696
697             cutoff_mask      = _mm_cmplt_pd(rsq00,rcutoff2);
698
699             fscal            = _mm_add_pd(felec,fvdw);
700
701             fscal            = _mm_and_pd(fscal,cutoff_mask);
702
703             fscal            = _mm_unpacklo_pd(fscal,_mm_setzero_pd());
704
705             /* Calculate temporary vectorial force */
706             tx               = _mm_mul_pd(fscal,dx00);
707             ty               = _mm_mul_pd(fscal,dy00);
708             tz               = _mm_mul_pd(fscal,dz00);
709
710             /* Update vectorial force */
711             fix0             = _mm_add_pd(fix0,tx);
712             fiy0             = _mm_add_pd(fiy0,ty);
713             fiz0             = _mm_add_pd(fiz0,tz);
714
715             gmx_mm_decrement_1rvec_1ptr_swizzle_pd(f+j_coord_offsetA,tx,ty,tz);
716
717             }
718
719             /* Inner loop uses 62 flops */
720         }
721
722         /* End of innermost loop */
723
724         gmx_mm_update_iforce_1atom_swizzle_pd(fix0,fiy0,fiz0,
725                                               f+i_coord_offset,fshift+i_shift_offset);
726
727         /* Increment number of inner iterations */
728         inneriter                  += j_index_end - j_index_start;
729
730         /* Outer loop uses 7 flops */
731     }
732
733     /* Increment number of outer iterations */
734     outeriter        += nri;
735
736     /* Update outer/inner flops */
737
738     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_F,outeriter*7 + inneriter*62);
739 }