90503c4aa7cf349ccbce0c08d79e888f9ffc3bbb
[alexxy/gromacs.git] / src / gromacs / gmxlib / nonbonded / nb_kernel_avx_256_double / nb_kernel_ElecGB_VdwCSTab_GeomP1P1_avx_256_double.c
1 /*
2  * This file is part of the GROMACS molecular simulation package.
3  *
4  * Copyright (c) 2012,2013, 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.
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34  */
35 /*
36  * Note: this file was generated by the GROMACS avx_256_double kernel generator.
37  */
38 #ifdef HAVE_CONFIG_H
39 #include <config.h>
40 #endif
41
42 #include <math.h>
43
44 #include "../nb_kernel.h"
45 #include "types/simple.h"
46 #include "vec.h"
47 #include "nrnb.h"
48
49 #include "gmx_math_x86_avx_256_double.h"
50 #include "kernelutil_x86_avx_256_double.h"
51
52 /*
53  * Gromacs nonbonded kernel:   nb_kernel_ElecGB_VdwCSTab_GeomP1P1_VF_avx_256_double
54  * Electrostatics interaction: GeneralizedBorn
55  * VdW interaction:            CubicSplineTable
56  * Geometry:                   Particle-Particle
57  * Calculate force/pot:        PotentialAndForce
58  */
59 void
60 nb_kernel_ElecGB_VdwCSTab_GeomP1P1_VF_avx_256_double
61                     (t_nblist                    * gmx_restrict       nlist,
62                      rvec                        * gmx_restrict          xx,
63                      rvec                        * gmx_restrict          ff,
64                      t_forcerec                  * gmx_restrict          fr,
65                      t_mdatoms                   * gmx_restrict     mdatoms,
66                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
67                      t_nrnb                      * gmx_restrict        nrnb)
68 {
69     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or 
70      * just 0 for non-waters.
71      * Suffixes A,B,C,D refer to j loop unrolling done with AVX, e.g. for the four different
72      * jnr indices corresponding to data put in the four positions in the SIMD register.
73      */
74     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
75     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
76     int              jnrA,jnrB,jnrC,jnrD;
77     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
78     int              jnrlistE,jnrlistF,jnrlistG,jnrlistH;
79     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
80     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
81     real             rcutoff_scalar;
82     real             *shiftvec,*fshift,*x,*f;
83     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
84     real             scratch[4*DIM];
85     __m256d          tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
86     real *           vdwioffsetptr0;
87     __m256d          ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
88     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
89     __m256d          jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
90     __m256d          dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
91     __m256d          velec,felec,velecsum,facel,crf,krf,krf2;
92     real             *charge;
93     __m128i          gbitab;
94     __m256d          vgb,fgb,vgbsum,dvdasum,gbscale,gbtabscale,isaprod,gbqqfactor,gbinvepsdiff,gbeps,dvdatmp;
95     __m256d          minushalf = _mm256_set1_pd(-0.5);
96     real             *invsqrta,*dvda,*gbtab;
97     int              nvdwtype;
98     __m256d          rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
99     int              *vdwtype;
100     real             *vdwparam;
101     __m256d          one_sixth   = _mm256_set1_pd(1.0/6.0);
102     __m256d          one_twelfth = _mm256_set1_pd(1.0/12.0);
103     __m128i          vfitab;
104     __m128i          ifour       = _mm_set1_epi32(4);
105     __m256d          rt,vfeps,vftabscale,Y,F,G,H,Heps,Fp,VV,FF;
106     real             *vftab;
107     __m256d          dummy_mask,cutoff_mask;
108     __m128           tmpmask0,tmpmask1;
109     __m256d          signbit = _mm256_castsi256_pd( _mm256_set1_epi32(0x80000000) );
110     __m256d          one     = _mm256_set1_pd(1.0);
111     __m256d          two     = _mm256_set1_pd(2.0);
112     x                = xx[0];
113     f                = ff[0];
114
115     nri              = nlist->nri;
116     iinr             = nlist->iinr;
117     jindex           = nlist->jindex;
118     jjnr             = nlist->jjnr;
119     shiftidx         = nlist->shift;
120     gid              = nlist->gid;
121     shiftvec         = fr->shift_vec[0];
122     fshift           = fr->fshift[0];
123     facel            = _mm256_set1_pd(fr->epsfac);
124     charge           = mdatoms->chargeA;
125     nvdwtype         = fr->ntype;
126     vdwparam         = fr->nbfp;
127     vdwtype          = mdatoms->typeA;
128
129     vftab            = kernel_data->table_vdw->data;
130     vftabscale       = _mm256_set1_pd(kernel_data->table_vdw->scale);
131
132     invsqrta         = fr->invsqrta;
133     dvda             = fr->dvda;
134     gbtabscale       = _mm256_set1_pd(fr->gbtab.scale);
135     gbtab            = fr->gbtab.data;
136     gbinvepsdiff     = _mm256_set1_pd((1.0/fr->epsilon_r) - (1.0/fr->gb_epsilon_solvent));
137
138     /* Avoid stupid compiler warnings */
139     jnrA = jnrB = jnrC = jnrD = 0;
140     j_coord_offsetA = 0;
141     j_coord_offsetB = 0;
142     j_coord_offsetC = 0;
143     j_coord_offsetD = 0;
144
145     outeriter        = 0;
146     inneriter        = 0;
147
148     for(iidx=0;iidx<4*DIM;iidx++)
149     {
150         scratch[iidx] = 0.0;
151     }
152
153     /* Start outer loop over neighborlists */
154     for(iidx=0; iidx<nri; iidx++)
155     {
156         /* Load shift vector for this list */
157         i_shift_offset   = DIM*shiftidx[iidx];
158
159         /* Load limits for loop over neighbors */
160         j_index_start    = jindex[iidx];
161         j_index_end      = jindex[iidx+1];
162
163         /* Get outer coordinate index */
164         inr              = iinr[iidx];
165         i_coord_offset   = DIM*inr;
166
167         /* Load i particle coords and add shift vector */
168         gmx_mm256_load_shift_and_1rvec_broadcast_pd(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
169
170         fix0             = _mm256_setzero_pd();
171         fiy0             = _mm256_setzero_pd();
172         fiz0             = _mm256_setzero_pd();
173
174         /* Load parameters for i particles */
175         iq0              = _mm256_mul_pd(facel,_mm256_set1_pd(charge[inr+0]));
176         isai0            = _mm256_set1_pd(invsqrta[inr+0]);
177         vdwioffsetptr0   = vdwparam+2*nvdwtype*vdwtype[inr+0];
178
179         /* Reset potential sums */
180         velecsum         = _mm256_setzero_pd();
181         vgbsum           = _mm256_setzero_pd();
182         vvdwsum          = _mm256_setzero_pd();
183         dvdasum          = _mm256_setzero_pd();
184
185         /* Start inner kernel loop */
186         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
187         {
188
189             /* Get j neighbor index, and coordinate index */
190             jnrA             = jjnr[jidx];
191             jnrB             = jjnr[jidx+1];
192             jnrC             = jjnr[jidx+2];
193             jnrD             = jjnr[jidx+3];
194             j_coord_offsetA  = DIM*jnrA;
195             j_coord_offsetB  = DIM*jnrB;
196             j_coord_offsetC  = DIM*jnrC;
197             j_coord_offsetD  = DIM*jnrD;
198
199             /* load j atom coordinates */
200             gmx_mm256_load_1rvec_4ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
201                                                  x+j_coord_offsetC,x+j_coord_offsetD,
202                                                  &jx0,&jy0,&jz0);
203
204             /* Calculate displacement vector */
205             dx00             = _mm256_sub_pd(ix0,jx0);
206             dy00             = _mm256_sub_pd(iy0,jy0);
207             dz00             = _mm256_sub_pd(iz0,jz0);
208
209             /* Calculate squared distance and things based on it */
210             rsq00            = gmx_mm256_calc_rsq_pd(dx00,dy00,dz00);
211
212             rinv00           = gmx_mm256_invsqrt_pd(rsq00);
213
214             /* Load parameters for j particles */
215             jq0              = gmx_mm256_load_4real_swizzle_pd(charge+jnrA+0,charge+jnrB+0,
216                                                                  charge+jnrC+0,charge+jnrD+0);
217             isaj0            = gmx_mm256_load_4real_swizzle_pd(invsqrta+jnrA+0,invsqrta+jnrB+0,
218                                                                  invsqrta+jnrC+0,invsqrta+jnrD+0);
219             vdwjidx0A        = 2*vdwtype[jnrA+0];
220             vdwjidx0B        = 2*vdwtype[jnrB+0];
221             vdwjidx0C        = 2*vdwtype[jnrC+0];
222             vdwjidx0D        = 2*vdwtype[jnrD+0];
223
224             /**************************
225              * CALCULATE INTERACTIONS *
226              **************************/
227
228             r00              = _mm256_mul_pd(rsq00,rinv00);
229
230             /* Compute parameters for interactions between i and j atoms */
231             qq00             = _mm256_mul_pd(iq0,jq0);
232             gmx_mm256_load_4pair_swizzle_pd(vdwioffsetptr0+vdwjidx0A,
233                                             vdwioffsetptr0+vdwjidx0B,
234                                             vdwioffsetptr0+vdwjidx0C,
235                                             vdwioffsetptr0+vdwjidx0D,
236                                             &c6_00,&c12_00);
237
238             /* Calculate table index by multiplying r with table scale and truncate to integer */
239             rt               = _mm256_mul_pd(r00,vftabscale);
240             vfitab           = _mm256_cvttpd_epi32(rt);
241             vfeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
242             vfitab           = _mm_slli_epi32(vfitab,3);
243
244             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
245             isaprod          = _mm256_mul_pd(isai0,isaj0);
246             gbqqfactor       = _mm256_xor_pd(signbit,_mm256_mul_pd(qq00,_mm256_mul_pd(isaprod,gbinvepsdiff)));
247             gbscale          = _mm256_mul_pd(isaprod,gbtabscale);
248
249             /* Calculate generalized born table index - this is a separate table from the normal one,
250              * but we use the same procedure by multiplying r with scale and truncating to integer.
251              */
252             rt               = _mm256_mul_pd(r00,gbscale);
253             gbitab           = _mm256_cvttpd_epi32(rt);
254             gbeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
255             gbitab           = _mm_slli_epi32(gbitab,2);
256             Y                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,0) );
257             F                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,1) );
258             G                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,2) );
259             H                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,3) );
260             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
261             Heps             = _mm256_mul_pd(gbeps,H);
262             Fp               = _mm256_add_pd(F,_mm256_mul_pd(gbeps,_mm256_add_pd(G,Heps)));
263             VV               = _mm256_add_pd(Y,_mm256_mul_pd(gbeps,Fp));
264             vgb              = _mm256_mul_pd(gbqqfactor,VV);
265
266             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(gbeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
267             fgb              = _mm256_mul_pd(gbqqfactor,_mm256_mul_pd(FF,gbscale));
268             dvdatmp          = _mm256_mul_pd(minushalf,_mm256_add_pd(vgb,_mm256_mul_pd(fgb,r00)));
269             dvdasum          = _mm256_add_pd(dvdasum,dvdatmp);
270             fjptrA           = dvda+jnrA;
271             fjptrB           = dvda+jnrB;
272             fjptrC           = dvda+jnrC;
273             fjptrD           = dvda+jnrD;
274             gmx_mm256_increment_4real_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,
275                                                  _mm256_mul_pd(dvdatmp,_mm256_mul_pd(isaj0,isaj0)));
276             velec            = _mm256_mul_pd(qq00,rinv00);
277             felec            = _mm256_mul_pd(_mm256_sub_pd(_mm256_mul_pd(velec,rinv00),fgb),rinv00);
278
279             /* CUBIC SPLINE TABLE DISPERSION */
280             Y                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,0) );
281             F                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,1) );
282             G                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,2) );
283             H                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,3) );
284             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
285             Heps             = _mm256_mul_pd(vfeps,H);
286             Fp               = _mm256_add_pd(F,_mm256_mul_pd(vfeps,_mm256_add_pd(G,Heps)));
287             VV               = _mm256_add_pd(Y,_mm256_mul_pd(vfeps,Fp));
288             vvdw6            = _mm256_mul_pd(c6_00,VV);
289             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(vfeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
290             fvdw6            = _mm256_mul_pd(c6_00,FF);
291
292             /* CUBIC SPLINE TABLE REPULSION */
293             vfitab           = _mm_add_epi32(vfitab,ifour);
294             Y                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,0) );
295             F                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,1) );
296             G                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,2) );
297             H                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,3) );
298             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
299             Heps             = _mm256_mul_pd(vfeps,H);
300             Fp               = _mm256_add_pd(F,_mm256_mul_pd(vfeps,_mm256_add_pd(G,Heps)));
301             VV               = _mm256_add_pd(Y,_mm256_mul_pd(vfeps,Fp));
302             vvdw12           = _mm256_mul_pd(c12_00,VV);
303             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(vfeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
304             fvdw12           = _mm256_mul_pd(c12_00,FF);
305             vvdw             = _mm256_add_pd(vvdw12,vvdw6);
306             fvdw             = _mm256_xor_pd(signbit,_mm256_mul_pd(_mm256_add_pd(fvdw6,fvdw12),_mm256_mul_pd(vftabscale,rinv00)));
307
308             /* Update potential sum for this i atom from the interaction with this j atom. */
309             velecsum         = _mm256_add_pd(velecsum,velec);
310             vgbsum           = _mm256_add_pd(vgbsum,vgb);
311             vvdwsum          = _mm256_add_pd(vvdwsum,vvdw);
312
313             fscal            = _mm256_add_pd(felec,fvdw);
314
315             /* Calculate temporary vectorial force */
316             tx               = _mm256_mul_pd(fscal,dx00);
317             ty               = _mm256_mul_pd(fscal,dy00);
318             tz               = _mm256_mul_pd(fscal,dz00);
319
320             /* Update vectorial force */
321             fix0             = _mm256_add_pd(fix0,tx);
322             fiy0             = _mm256_add_pd(fiy0,ty);
323             fiz0             = _mm256_add_pd(fiz0,tz);
324
325             fjptrA             = f+j_coord_offsetA;
326             fjptrB             = f+j_coord_offsetB;
327             fjptrC             = f+j_coord_offsetC;
328             fjptrD             = f+j_coord_offsetD;
329             gmx_mm256_decrement_1rvec_4ptr_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
330
331             /* Inner loop uses 91 flops */
332         }
333
334         if(jidx<j_index_end)
335         {
336
337             /* Get j neighbor index, and coordinate index */
338             jnrlistA         = jjnr[jidx];
339             jnrlistB         = jjnr[jidx+1];
340             jnrlistC         = jjnr[jidx+2];
341             jnrlistD         = jjnr[jidx+3];
342             /* Sign of each element will be negative for non-real atoms.
343              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
344              * so use it as val = _mm_andnot_pd(mask,val) to clear dummy entries.
345              */
346             tmpmask0 = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
347
348             tmpmask1 = _mm_permute_ps(tmpmask0,_GMX_MM_PERMUTE(3,3,2,2));
349             tmpmask0 = _mm_permute_ps(tmpmask0,_GMX_MM_PERMUTE(1,1,0,0));
350             dummy_mask = _mm256_castps_pd(gmx_mm256_set_m128(tmpmask1,tmpmask0));
351
352             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
353             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
354             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
355             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
356             j_coord_offsetA  = DIM*jnrA;
357             j_coord_offsetB  = DIM*jnrB;
358             j_coord_offsetC  = DIM*jnrC;
359             j_coord_offsetD  = DIM*jnrD;
360
361             /* load j atom coordinates */
362             gmx_mm256_load_1rvec_4ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
363                                                  x+j_coord_offsetC,x+j_coord_offsetD,
364                                                  &jx0,&jy0,&jz0);
365
366             /* Calculate displacement vector */
367             dx00             = _mm256_sub_pd(ix0,jx0);
368             dy00             = _mm256_sub_pd(iy0,jy0);
369             dz00             = _mm256_sub_pd(iz0,jz0);
370
371             /* Calculate squared distance and things based on it */
372             rsq00            = gmx_mm256_calc_rsq_pd(dx00,dy00,dz00);
373
374             rinv00           = gmx_mm256_invsqrt_pd(rsq00);
375
376             /* Load parameters for j particles */
377             jq0              = gmx_mm256_load_4real_swizzle_pd(charge+jnrA+0,charge+jnrB+0,
378                                                                  charge+jnrC+0,charge+jnrD+0);
379             isaj0            = gmx_mm256_load_4real_swizzle_pd(invsqrta+jnrA+0,invsqrta+jnrB+0,
380                                                                  invsqrta+jnrC+0,invsqrta+jnrD+0);
381             vdwjidx0A        = 2*vdwtype[jnrA+0];
382             vdwjidx0B        = 2*vdwtype[jnrB+0];
383             vdwjidx0C        = 2*vdwtype[jnrC+0];
384             vdwjidx0D        = 2*vdwtype[jnrD+0];
385
386             /**************************
387              * CALCULATE INTERACTIONS *
388              **************************/
389
390             r00              = _mm256_mul_pd(rsq00,rinv00);
391             r00              = _mm256_andnot_pd(dummy_mask,r00);
392
393             /* Compute parameters for interactions between i and j atoms */
394             qq00             = _mm256_mul_pd(iq0,jq0);
395             gmx_mm256_load_4pair_swizzle_pd(vdwioffsetptr0+vdwjidx0A,
396                                             vdwioffsetptr0+vdwjidx0B,
397                                             vdwioffsetptr0+vdwjidx0C,
398                                             vdwioffsetptr0+vdwjidx0D,
399                                             &c6_00,&c12_00);
400
401             /* Calculate table index by multiplying r with table scale and truncate to integer */
402             rt               = _mm256_mul_pd(r00,vftabscale);
403             vfitab           = _mm256_cvttpd_epi32(rt);
404             vfeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
405             vfitab           = _mm_slli_epi32(vfitab,3);
406
407             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
408             isaprod          = _mm256_mul_pd(isai0,isaj0);
409             gbqqfactor       = _mm256_xor_pd(signbit,_mm256_mul_pd(qq00,_mm256_mul_pd(isaprod,gbinvepsdiff)));
410             gbscale          = _mm256_mul_pd(isaprod,gbtabscale);
411
412             /* Calculate generalized born table index - this is a separate table from the normal one,
413              * but we use the same procedure by multiplying r with scale and truncating to integer.
414              */
415             rt               = _mm256_mul_pd(r00,gbscale);
416             gbitab           = _mm256_cvttpd_epi32(rt);
417             gbeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
418             gbitab           = _mm_slli_epi32(gbitab,2);
419             Y                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,0) );
420             F                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,1) );
421             G                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,2) );
422             H                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,3) );
423             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
424             Heps             = _mm256_mul_pd(gbeps,H);
425             Fp               = _mm256_add_pd(F,_mm256_mul_pd(gbeps,_mm256_add_pd(G,Heps)));
426             VV               = _mm256_add_pd(Y,_mm256_mul_pd(gbeps,Fp));
427             vgb              = _mm256_mul_pd(gbqqfactor,VV);
428
429             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(gbeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
430             fgb              = _mm256_mul_pd(gbqqfactor,_mm256_mul_pd(FF,gbscale));
431             dvdatmp          = _mm256_mul_pd(minushalf,_mm256_add_pd(vgb,_mm256_mul_pd(fgb,r00)));
432             dvdatmp          = _mm256_andnot_pd(dummy_mask,dvdatmp);
433             dvdasum          = _mm256_add_pd(dvdasum,dvdatmp);
434             /* The pointers to scratch make sure that this code with compilers that take gmx_restrict seriously (e.g. icc 13) really can't screw things up. */
435             fjptrA             = (jnrlistA>=0) ? dvda+jnrA : scratch;
436             fjptrB             = (jnrlistB>=0) ? dvda+jnrB : scratch;
437             fjptrC             = (jnrlistC>=0) ? dvda+jnrC : scratch;
438             fjptrD             = (jnrlistD>=0) ? dvda+jnrD : scratch;
439             gmx_mm256_increment_4real_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,
440                                                  _mm256_mul_pd(dvdatmp,_mm256_mul_pd(isaj0,isaj0)));
441             velec            = _mm256_mul_pd(qq00,rinv00);
442             felec            = _mm256_mul_pd(_mm256_sub_pd(_mm256_mul_pd(velec,rinv00),fgb),rinv00);
443
444             /* CUBIC SPLINE TABLE DISPERSION */
445             Y                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,0) );
446             F                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,1) );
447             G                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,2) );
448             H                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,3) );
449             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
450             Heps             = _mm256_mul_pd(vfeps,H);
451             Fp               = _mm256_add_pd(F,_mm256_mul_pd(vfeps,_mm256_add_pd(G,Heps)));
452             VV               = _mm256_add_pd(Y,_mm256_mul_pd(vfeps,Fp));
453             vvdw6            = _mm256_mul_pd(c6_00,VV);
454             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(vfeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
455             fvdw6            = _mm256_mul_pd(c6_00,FF);
456
457             /* CUBIC SPLINE TABLE REPULSION */
458             vfitab           = _mm_add_epi32(vfitab,ifour);
459             Y                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,0) );
460             F                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,1) );
461             G                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,2) );
462             H                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,3) );
463             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
464             Heps             = _mm256_mul_pd(vfeps,H);
465             Fp               = _mm256_add_pd(F,_mm256_mul_pd(vfeps,_mm256_add_pd(G,Heps)));
466             VV               = _mm256_add_pd(Y,_mm256_mul_pd(vfeps,Fp));
467             vvdw12           = _mm256_mul_pd(c12_00,VV);
468             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(vfeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
469             fvdw12           = _mm256_mul_pd(c12_00,FF);
470             vvdw             = _mm256_add_pd(vvdw12,vvdw6);
471             fvdw             = _mm256_xor_pd(signbit,_mm256_mul_pd(_mm256_add_pd(fvdw6,fvdw12),_mm256_mul_pd(vftabscale,rinv00)));
472
473             /* Update potential sum for this i atom from the interaction with this j atom. */
474             velec            = _mm256_andnot_pd(dummy_mask,velec);
475             velecsum         = _mm256_add_pd(velecsum,velec);
476             vgb              = _mm256_andnot_pd(dummy_mask,vgb);
477             vgbsum           = _mm256_add_pd(vgbsum,vgb);
478             vvdw             = _mm256_andnot_pd(dummy_mask,vvdw);
479             vvdwsum          = _mm256_add_pd(vvdwsum,vvdw);
480
481             fscal            = _mm256_add_pd(felec,fvdw);
482
483             fscal            = _mm256_andnot_pd(dummy_mask,fscal);
484
485             /* Calculate temporary vectorial force */
486             tx               = _mm256_mul_pd(fscal,dx00);
487             ty               = _mm256_mul_pd(fscal,dy00);
488             tz               = _mm256_mul_pd(fscal,dz00);
489
490             /* Update vectorial force */
491             fix0             = _mm256_add_pd(fix0,tx);
492             fiy0             = _mm256_add_pd(fiy0,ty);
493             fiz0             = _mm256_add_pd(fiz0,tz);
494
495             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
496             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
497             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
498             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
499             gmx_mm256_decrement_1rvec_4ptr_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
500
501             /* Inner loop uses 92 flops */
502         }
503
504         /* End of innermost loop */
505
506         gmx_mm256_update_iforce_1atom_swizzle_pd(fix0,fiy0,fiz0,
507                                                  f+i_coord_offset,fshift+i_shift_offset);
508
509         ggid                        = gid[iidx];
510         /* Update potential energies */
511         gmx_mm256_update_1pot_pd(velecsum,kernel_data->energygrp_elec+ggid);
512         gmx_mm256_update_1pot_pd(vgbsum,kernel_data->energygrp_polarization+ggid);
513         gmx_mm256_update_1pot_pd(vvdwsum,kernel_data->energygrp_vdw+ggid);
514         dvdasum = _mm256_mul_pd(dvdasum, _mm256_mul_pd(isai0,isai0));
515         gmx_mm256_update_1pot_pd(dvdasum,dvda+inr);
516
517         /* Increment number of inner iterations */
518         inneriter                  += j_index_end - j_index_start;
519
520         /* Outer loop uses 10 flops */
521     }
522
523     /* Increment number of outer iterations */
524     outeriter        += nri;
525
526     /* Update outer/inner flops */
527
528     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_VF,outeriter*10 + inneriter*92);
529 }
530 /*
531  * Gromacs nonbonded kernel:   nb_kernel_ElecGB_VdwCSTab_GeomP1P1_F_avx_256_double
532  * Electrostatics interaction: GeneralizedBorn
533  * VdW interaction:            CubicSplineTable
534  * Geometry:                   Particle-Particle
535  * Calculate force/pot:        Force
536  */
537 void
538 nb_kernel_ElecGB_VdwCSTab_GeomP1P1_F_avx_256_double
539                     (t_nblist                    * gmx_restrict       nlist,
540                      rvec                        * gmx_restrict          xx,
541                      rvec                        * gmx_restrict          ff,
542                      t_forcerec                  * gmx_restrict          fr,
543                      t_mdatoms                   * gmx_restrict     mdatoms,
544                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
545                      t_nrnb                      * gmx_restrict        nrnb)
546 {
547     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or 
548      * just 0 for non-waters.
549      * Suffixes A,B,C,D refer to j loop unrolling done with AVX, e.g. for the four different
550      * jnr indices corresponding to data put in the four positions in the SIMD register.
551      */
552     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
553     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
554     int              jnrA,jnrB,jnrC,jnrD;
555     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
556     int              jnrlistE,jnrlistF,jnrlistG,jnrlistH;
557     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
558     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
559     real             rcutoff_scalar;
560     real             *shiftvec,*fshift,*x,*f;
561     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
562     real             scratch[4*DIM];
563     __m256d          tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
564     real *           vdwioffsetptr0;
565     __m256d          ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
566     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
567     __m256d          jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
568     __m256d          dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
569     __m256d          velec,felec,velecsum,facel,crf,krf,krf2;
570     real             *charge;
571     __m128i          gbitab;
572     __m256d          vgb,fgb,vgbsum,dvdasum,gbscale,gbtabscale,isaprod,gbqqfactor,gbinvepsdiff,gbeps,dvdatmp;
573     __m256d          minushalf = _mm256_set1_pd(-0.5);
574     real             *invsqrta,*dvda,*gbtab;
575     int              nvdwtype;
576     __m256d          rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
577     int              *vdwtype;
578     real             *vdwparam;
579     __m256d          one_sixth   = _mm256_set1_pd(1.0/6.0);
580     __m256d          one_twelfth = _mm256_set1_pd(1.0/12.0);
581     __m128i          vfitab;
582     __m128i          ifour       = _mm_set1_epi32(4);
583     __m256d          rt,vfeps,vftabscale,Y,F,G,H,Heps,Fp,VV,FF;
584     real             *vftab;
585     __m256d          dummy_mask,cutoff_mask;
586     __m128           tmpmask0,tmpmask1;
587     __m256d          signbit = _mm256_castsi256_pd( _mm256_set1_epi32(0x80000000) );
588     __m256d          one     = _mm256_set1_pd(1.0);
589     __m256d          two     = _mm256_set1_pd(2.0);
590     x                = xx[0];
591     f                = ff[0];
592
593     nri              = nlist->nri;
594     iinr             = nlist->iinr;
595     jindex           = nlist->jindex;
596     jjnr             = nlist->jjnr;
597     shiftidx         = nlist->shift;
598     gid              = nlist->gid;
599     shiftvec         = fr->shift_vec[0];
600     fshift           = fr->fshift[0];
601     facel            = _mm256_set1_pd(fr->epsfac);
602     charge           = mdatoms->chargeA;
603     nvdwtype         = fr->ntype;
604     vdwparam         = fr->nbfp;
605     vdwtype          = mdatoms->typeA;
606
607     vftab            = kernel_data->table_vdw->data;
608     vftabscale       = _mm256_set1_pd(kernel_data->table_vdw->scale);
609
610     invsqrta         = fr->invsqrta;
611     dvda             = fr->dvda;
612     gbtabscale       = _mm256_set1_pd(fr->gbtab.scale);
613     gbtab            = fr->gbtab.data;
614     gbinvepsdiff     = _mm256_set1_pd((1.0/fr->epsilon_r) - (1.0/fr->gb_epsilon_solvent));
615
616     /* Avoid stupid compiler warnings */
617     jnrA = jnrB = jnrC = jnrD = 0;
618     j_coord_offsetA = 0;
619     j_coord_offsetB = 0;
620     j_coord_offsetC = 0;
621     j_coord_offsetD = 0;
622
623     outeriter        = 0;
624     inneriter        = 0;
625
626     for(iidx=0;iidx<4*DIM;iidx++)
627     {
628         scratch[iidx] = 0.0;
629     }
630
631     /* Start outer loop over neighborlists */
632     for(iidx=0; iidx<nri; iidx++)
633     {
634         /* Load shift vector for this list */
635         i_shift_offset   = DIM*shiftidx[iidx];
636
637         /* Load limits for loop over neighbors */
638         j_index_start    = jindex[iidx];
639         j_index_end      = jindex[iidx+1];
640
641         /* Get outer coordinate index */
642         inr              = iinr[iidx];
643         i_coord_offset   = DIM*inr;
644
645         /* Load i particle coords and add shift vector */
646         gmx_mm256_load_shift_and_1rvec_broadcast_pd(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
647
648         fix0             = _mm256_setzero_pd();
649         fiy0             = _mm256_setzero_pd();
650         fiz0             = _mm256_setzero_pd();
651
652         /* Load parameters for i particles */
653         iq0              = _mm256_mul_pd(facel,_mm256_set1_pd(charge[inr+0]));
654         isai0            = _mm256_set1_pd(invsqrta[inr+0]);
655         vdwioffsetptr0   = vdwparam+2*nvdwtype*vdwtype[inr+0];
656
657         dvdasum          = _mm256_setzero_pd();
658
659         /* Start inner kernel loop */
660         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
661         {
662
663             /* Get j neighbor index, and coordinate index */
664             jnrA             = jjnr[jidx];
665             jnrB             = jjnr[jidx+1];
666             jnrC             = jjnr[jidx+2];
667             jnrD             = jjnr[jidx+3];
668             j_coord_offsetA  = DIM*jnrA;
669             j_coord_offsetB  = DIM*jnrB;
670             j_coord_offsetC  = DIM*jnrC;
671             j_coord_offsetD  = DIM*jnrD;
672
673             /* load j atom coordinates */
674             gmx_mm256_load_1rvec_4ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
675                                                  x+j_coord_offsetC,x+j_coord_offsetD,
676                                                  &jx0,&jy0,&jz0);
677
678             /* Calculate displacement vector */
679             dx00             = _mm256_sub_pd(ix0,jx0);
680             dy00             = _mm256_sub_pd(iy0,jy0);
681             dz00             = _mm256_sub_pd(iz0,jz0);
682
683             /* Calculate squared distance and things based on it */
684             rsq00            = gmx_mm256_calc_rsq_pd(dx00,dy00,dz00);
685
686             rinv00           = gmx_mm256_invsqrt_pd(rsq00);
687
688             /* Load parameters for j particles */
689             jq0              = gmx_mm256_load_4real_swizzle_pd(charge+jnrA+0,charge+jnrB+0,
690                                                                  charge+jnrC+0,charge+jnrD+0);
691             isaj0            = gmx_mm256_load_4real_swizzle_pd(invsqrta+jnrA+0,invsqrta+jnrB+0,
692                                                                  invsqrta+jnrC+0,invsqrta+jnrD+0);
693             vdwjidx0A        = 2*vdwtype[jnrA+0];
694             vdwjidx0B        = 2*vdwtype[jnrB+0];
695             vdwjidx0C        = 2*vdwtype[jnrC+0];
696             vdwjidx0D        = 2*vdwtype[jnrD+0];
697
698             /**************************
699              * CALCULATE INTERACTIONS *
700              **************************/
701
702             r00              = _mm256_mul_pd(rsq00,rinv00);
703
704             /* Compute parameters for interactions between i and j atoms */
705             qq00             = _mm256_mul_pd(iq0,jq0);
706             gmx_mm256_load_4pair_swizzle_pd(vdwioffsetptr0+vdwjidx0A,
707                                             vdwioffsetptr0+vdwjidx0B,
708                                             vdwioffsetptr0+vdwjidx0C,
709                                             vdwioffsetptr0+vdwjidx0D,
710                                             &c6_00,&c12_00);
711
712             /* Calculate table index by multiplying r with table scale and truncate to integer */
713             rt               = _mm256_mul_pd(r00,vftabscale);
714             vfitab           = _mm256_cvttpd_epi32(rt);
715             vfeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
716             vfitab           = _mm_slli_epi32(vfitab,3);
717
718             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
719             isaprod          = _mm256_mul_pd(isai0,isaj0);
720             gbqqfactor       = _mm256_xor_pd(signbit,_mm256_mul_pd(qq00,_mm256_mul_pd(isaprod,gbinvepsdiff)));
721             gbscale          = _mm256_mul_pd(isaprod,gbtabscale);
722
723             /* Calculate generalized born table index - this is a separate table from the normal one,
724              * but we use the same procedure by multiplying r with scale and truncating to integer.
725              */
726             rt               = _mm256_mul_pd(r00,gbscale);
727             gbitab           = _mm256_cvttpd_epi32(rt);
728             gbeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
729             gbitab           = _mm_slli_epi32(gbitab,2);
730             Y                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,0) );
731             F                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,1) );
732             G                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,2) );
733             H                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,3) );
734             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
735             Heps             = _mm256_mul_pd(gbeps,H);
736             Fp               = _mm256_add_pd(F,_mm256_mul_pd(gbeps,_mm256_add_pd(G,Heps)));
737             VV               = _mm256_add_pd(Y,_mm256_mul_pd(gbeps,Fp));
738             vgb              = _mm256_mul_pd(gbqqfactor,VV);
739
740             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(gbeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
741             fgb              = _mm256_mul_pd(gbqqfactor,_mm256_mul_pd(FF,gbscale));
742             dvdatmp          = _mm256_mul_pd(minushalf,_mm256_add_pd(vgb,_mm256_mul_pd(fgb,r00)));
743             dvdasum          = _mm256_add_pd(dvdasum,dvdatmp);
744             fjptrA           = dvda+jnrA;
745             fjptrB           = dvda+jnrB;
746             fjptrC           = dvda+jnrC;
747             fjptrD           = dvda+jnrD;
748             gmx_mm256_increment_4real_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,
749                                                  _mm256_mul_pd(dvdatmp,_mm256_mul_pd(isaj0,isaj0)));
750             velec            = _mm256_mul_pd(qq00,rinv00);
751             felec            = _mm256_mul_pd(_mm256_sub_pd(_mm256_mul_pd(velec,rinv00),fgb),rinv00);
752
753             /* CUBIC SPLINE TABLE DISPERSION */
754             Y                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,0) );
755             F                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,1) );
756             G                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,2) );
757             H                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,3) );
758             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
759             Heps             = _mm256_mul_pd(vfeps,H);
760             Fp               = _mm256_add_pd(F,_mm256_mul_pd(vfeps,_mm256_add_pd(G,Heps)));
761             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(vfeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
762             fvdw6            = _mm256_mul_pd(c6_00,FF);
763
764             /* CUBIC SPLINE TABLE REPULSION */
765             vfitab           = _mm_add_epi32(vfitab,ifour);
766             Y                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,0) );
767             F                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,1) );
768             G                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,2) );
769             H                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,3) );
770             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
771             Heps             = _mm256_mul_pd(vfeps,H);
772             Fp               = _mm256_add_pd(F,_mm256_mul_pd(vfeps,_mm256_add_pd(G,Heps)));
773             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(vfeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
774             fvdw12           = _mm256_mul_pd(c12_00,FF);
775             fvdw             = _mm256_xor_pd(signbit,_mm256_mul_pd(_mm256_add_pd(fvdw6,fvdw12),_mm256_mul_pd(vftabscale,rinv00)));
776
777             fscal            = _mm256_add_pd(felec,fvdw);
778
779             /* Calculate temporary vectorial force */
780             tx               = _mm256_mul_pd(fscal,dx00);
781             ty               = _mm256_mul_pd(fscal,dy00);
782             tz               = _mm256_mul_pd(fscal,dz00);
783
784             /* Update vectorial force */
785             fix0             = _mm256_add_pd(fix0,tx);
786             fiy0             = _mm256_add_pd(fiy0,ty);
787             fiz0             = _mm256_add_pd(fiz0,tz);
788
789             fjptrA             = f+j_coord_offsetA;
790             fjptrB             = f+j_coord_offsetB;
791             fjptrC             = f+j_coord_offsetC;
792             fjptrD             = f+j_coord_offsetD;
793             gmx_mm256_decrement_1rvec_4ptr_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
794
795             /* Inner loop uses 81 flops */
796         }
797
798         if(jidx<j_index_end)
799         {
800
801             /* Get j neighbor index, and coordinate index */
802             jnrlistA         = jjnr[jidx];
803             jnrlistB         = jjnr[jidx+1];
804             jnrlistC         = jjnr[jidx+2];
805             jnrlistD         = jjnr[jidx+3];
806             /* Sign of each element will be negative for non-real atoms.
807              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
808              * so use it as val = _mm_andnot_pd(mask,val) to clear dummy entries.
809              */
810             tmpmask0 = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
811
812             tmpmask1 = _mm_permute_ps(tmpmask0,_GMX_MM_PERMUTE(3,3,2,2));
813             tmpmask0 = _mm_permute_ps(tmpmask0,_GMX_MM_PERMUTE(1,1,0,0));
814             dummy_mask = _mm256_castps_pd(gmx_mm256_set_m128(tmpmask1,tmpmask0));
815
816             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
817             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
818             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
819             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
820             j_coord_offsetA  = DIM*jnrA;
821             j_coord_offsetB  = DIM*jnrB;
822             j_coord_offsetC  = DIM*jnrC;
823             j_coord_offsetD  = DIM*jnrD;
824
825             /* load j atom coordinates */
826             gmx_mm256_load_1rvec_4ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
827                                                  x+j_coord_offsetC,x+j_coord_offsetD,
828                                                  &jx0,&jy0,&jz0);
829
830             /* Calculate displacement vector */
831             dx00             = _mm256_sub_pd(ix0,jx0);
832             dy00             = _mm256_sub_pd(iy0,jy0);
833             dz00             = _mm256_sub_pd(iz0,jz0);
834
835             /* Calculate squared distance and things based on it */
836             rsq00            = gmx_mm256_calc_rsq_pd(dx00,dy00,dz00);
837
838             rinv00           = gmx_mm256_invsqrt_pd(rsq00);
839
840             /* Load parameters for j particles */
841             jq0              = gmx_mm256_load_4real_swizzle_pd(charge+jnrA+0,charge+jnrB+0,
842                                                                  charge+jnrC+0,charge+jnrD+0);
843             isaj0            = gmx_mm256_load_4real_swizzle_pd(invsqrta+jnrA+0,invsqrta+jnrB+0,
844                                                                  invsqrta+jnrC+0,invsqrta+jnrD+0);
845             vdwjidx0A        = 2*vdwtype[jnrA+0];
846             vdwjidx0B        = 2*vdwtype[jnrB+0];
847             vdwjidx0C        = 2*vdwtype[jnrC+0];
848             vdwjidx0D        = 2*vdwtype[jnrD+0];
849
850             /**************************
851              * CALCULATE INTERACTIONS *
852              **************************/
853
854             r00              = _mm256_mul_pd(rsq00,rinv00);
855             r00              = _mm256_andnot_pd(dummy_mask,r00);
856
857             /* Compute parameters for interactions between i and j atoms */
858             qq00             = _mm256_mul_pd(iq0,jq0);
859             gmx_mm256_load_4pair_swizzle_pd(vdwioffsetptr0+vdwjidx0A,
860                                             vdwioffsetptr0+vdwjidx0B,
861                                             vdwioffsetptr0+vdwjidx0C,
862                                             vdwioffsetptr0+vdwjidx0D,
863                                             &c6_00,&c12_00);
864
865             /* Calculate table index by multiplying r with table scale and truncate to integer */
866             rt               = _mm256_mul_pd(r00,vftabscale);
867             vfitab           = _mm256_cvttpd_epi32(rt);
868             vfeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
869             vfitab           = _mm_slli_epi32(vfitab,3);
870
871             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
872             isaprod          = _mm256_mul_pd(isai0,isaj0);
873             gbqqfactor       = _mm256_xor_pd(signbit,_mm256_mul_pd(qq00,_mm256_mul_pd(isaprod,gbinvepsdiff)));
874             gbscale          = _mm256_mul_pd(isaprod,gbtabscale);
875
876             /* Calculate generalized born table index - this is a separate table from the normal one,
877              * but we use the same procedure by multiplying r with scale and truncating to integer.
878              */
879             rt               = _mm256_mul_pd(r00,gbscale);
880             gbitab           = _mm256_cvttpd_epi32(rt);
881             gbeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
882             gbitab           = _mm_slli_epi32(gbitab,2);
883             Y                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,0) );
884             F                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,1) );
885             G                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,2) );
886             H                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,3) );
887             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
888             Heps             = _mm256_mul_pd(gbeps,H);
889             Fp               = _mm256_add_pd(F,_mm256_mul_pd(gbeps,_mm256_add_pd(G,Heps)));
890             VV               = _mm256_add_pd(Y,_mm256_mul_pd(gbeps,Fp));
891             vgb              = _mm256_mul_pd(gbqqfactor,VV);
892
893             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(gbeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
894             fgb              = _mm256_mul_pd(gbqqfactor,_mm256_mul_pd(FF,gbscale));
895             dvdatmp          = _mm256_mul_pd(minushalf,_mm256_add_pd(vgb,_mm256_mul_pd(fgb,r00)));
896             dvdatmp          = _mm256_andnot_pd(dummy_mask,dvdatmp);
897             dvdasum          = _mm256_add_pd(dvdasum,dvdatmp);
898             /* The pointers to scratch make sure that this code with compilers that take gmx_restrict seriously (e.g. icc 13) really can't screw things up. */
899             fjptrA             = (jnrlistA>=0) ? dvda+jnrA : scratch;
900             fjptrB             = (jnrlistB>=0) ? dvda+jnrB : scratch;
901             fjptrC             = (jnrlistC>=0) ? dvda+jnrC : scratch;
902             fjptrD             = (jnrlistD>=0) ? dvda+jnrD : scratch;
903             gmx_mm256_increment_4real_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,
904                                                  _mm256_mul_pd(dvdatmp,_mm256_mul_pd(isaj0,isaj0)));
905             velec            = _mm256_mul_pd(qq00,rinv00);
906             felec            = _mm256_mul_pd(_mm256_sub_pd(_mm256_mul_pd(velec,rinv00),fgb),rinv00);
907
908             /* CUBIC SPLINE TABLE DISPERSION */
909             Y                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,0) );
910             F                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,1) );
911             G                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,2) );
912             H                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,3) );
913             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
914             Heps             = _mm256_mul_pd(vfeps,H);
915             Fp               = _mm256_add_pd(F,_mm256_mul_pd(vfeps,_mm256_add_pd(G,Heps)));
916             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(vfeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
917             fvdw6            = _mm256_mul_pd(c6_00,FF);
918
919             /* CUBIC SPLINE TABLE REPULSION */
920             vfitab           = _mm_add_epi32(vfitab,ifour);
921             Y                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,0) );
922             F                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,1) );
923             G                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,2) );
924             H                = _mm256_load_pd( vftab + _mm_extract_epi32(vfitab,3) );
925             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
926             Heps             = _mm256_mul_pd(vfeps,H);
927             Fp               = _mm256_add_pd(F,_mm256_mul_pd(vfeps,_mm256_add_pd(G,Heps)));
928             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(vfeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
929             fvdw12           = _mm256_mul_pd(c12_00,FF);
930             fvdw             = _mm256_xor_pd(signbit,_mm256_mul_pd(_mm256_add_pd(fvdw6,fvdw12),_mm256_mul_pd(vftabscale,rinv00)));
931
932             fscal            = _mm256_add_pd(felec,fvdw);
933
934             fscal            = _mm256_andnot_pd(dummy_mask,fscal);
935
936             /* Calculate temporary vectorial force */
937             tx               = _mm256_mul_pd(fscal,dx00);
938             ty               = _mm256_mul_pd(fscal,dy00);
939             tz               = _mm256_mul_pd(fscal,dz00);
940
941             /* Update vectorial force */
942             fix0             = _mm256_add_pd(fix0,tx);
943             fiy0             = _mm256_add_pd(fiy0,ty);
944             fiz0             = _mm256_add_pd(fiz0,tz);
945
946             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
947             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
948             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
949             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
950             gmx_mm256_decrement_1rvec_4ptr_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
951
952             /* Inner loop uses 82 flops */
953         }
954
955         /* End of innermost loop */
956
957         gmx_mm256_update_iforce_1atom_swizzle_pd(fix0,fiy0,fiz0,
958                                                  f+i_coord_offset,fshift+i_shift_offset);
959
960         dvdasum = _mm256_mul_pd(dvdasum, _mm256_mul_pd(isai0,isai0));
961         gmx_mm256_update_1pot_pd(dvdasum,dvda+inr);
962
963         /* Increment number of inner iterations */
964         inneriter                  += j_index_end - j_index_start;
965
966         /* Outer loop uses 7 flops */
967     }
968
969     /* Increment number of outer iterations */
970     outeriter        += nri;
971
972     /* Update outer/inner flops */
973
974     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_F,outeriter*7 + inneriter*82);
975 }