src/gromacs/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecCoul_VdwLJ_GeomW3P1_c.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,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with GROMACS; if not, see
  21  * http://www.gnu.org/licenses, or write to the Free Software Foundation,
  22  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
  23  *
  24  * If you want to redistribute modifications to GROMACS, please
  25  * consider that scientific software is very special. Version
  26  * control is crucial - bugs must be traceable. We will be happy to
  27  * consider code for inclusion in the official distribution, but
  28  * derived work must not be called official GROMACS. Details are found
  29  * in the README & COPYING files - if they are missing, get the
  30  * official version at http://www.gromacs.org.
  31  *
  32  * To help us fund GROMACS development, we humbly ask that you cite
  33  * the research papers on the package. Check out http://www.gromacs.org.
  34  */
  35 /*
  36  * Note: this file was generated by the GROMACS c 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 "gromacs/math/vec.h"
  47 #include "nrnb.h"
  48
  49 /*
  50  * Gromacs nonbonded kernel:   nb_kernel_ElecCoul_VdwLJ_GeomW3P1_VF_c
  51  * Electrostatics interaction: Coulomb
  52  * VdW interaction:            LennardJones
  53  * Geometry:                   Water3-Particle
  54  * Calculate force/pot:        PotentialAndForce
  55  */
  56 void
  57 nb_kernel_ElecCoul_VdwLJ_GeomW3P1_VF_c
  58                     (t_nblist                    * gmx_restrict       nlist,
  59                      rvec                        * gmx_restrict          xx,
  60                      rvec                        * gmx_restrict          ff,
  61                      t_forcerec                  * gmx_restrict          fr,
  62                      t_mdatoms                   * gmx_restrict     mdatoms,
  63                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
  64                      t_nrnb                      * gmx_restrict        nrnb)
  65 {
  66     int              i_shift_offset,i_coord_offset,j_coord_offset;
  67     int              j_index_start,j_index_end;
  68     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
  69     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
  70     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  71     real             *shiftvec,*fshift,*x,*f;
  72     int              vdwioffset0;
  73     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  74     int              vdwioffset1;
  75     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
  76     int              vdwioffset2;
  77     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
  78     int              vdwjidx0;
  79     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  80     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
  81     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
  82     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
  83     real             velec,felec,velecsum,facel,crf,krf,krf2;
  84     real             *charge;
  85     int              nvdwtype;
  86     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
  87     int              *vdwtype;
  88     real             *vdwparam;
  89
  90     x                = xx[0];
  91     f                = ff[0];
  92
  93     nri              = nlist->nri;
  94     iinr             = nlist->iinr;
  95     jindex           = nlist->jindex;
  96     jjnr             = nlist->jjnr;
  97     shiftidx         = nlist->shift;
  98     gid              = nlist->gid;
  99     shiftvec         = fr->shift_vec[0];
 100     fshift           = fr->fshift[0];
 101     facel            = fr->epsfac;
 102     charge           = mdatoms->chargeA;
 103     nvdwtype         = fr->ntype;
 104     vdwparam         = fr->nbfp;
 105     vdwtype          = mdatoms->typeA;
 106
 107     /* Setup water-specific parameters */
 108     inr              = nlist->iinr[0];
 109     iq0              = facel*charge[inr+0];
 110     iq1              = facel*charge[inr+1];
 111     iq2              = facel*charge[inr+2];
 112     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 113
 114     outeriter        = 0;
 115     inneriter        = 0;
 116
 117     /* Start outer loop over neighborlists */
 118     for(iidx=0; iidx<nri; iidx++)
 119     {
 120         /* Load shift vector for this list */
 121         i_shift_offset   = DIM*shiftidx[iidx];
 122         shX              = shiftvec[i_shift_offset+XX];
 123         shY              = shiftvec[i_shift_offset+YY];
 124         shZ              = shiftvec[i_shift_offset+ZZ];
 125
 126         /* Load limits for loop over neighbors */
 127         j_index_start    = jindex[iidx];
 128         j_index_end      = jindex[iidx+1];
 129
 130         /* Get outer coordinate index */
 131         inr              = iinr[iidx];
 132         i_coord_offset   = DIM*inr;
 133
 134         /* Load i particle coords and add shift vector */
 135         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 136         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 137         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 138         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 139         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 140         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 141         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 142         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 143         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 144
 145         fix0             = 0.0;
 146         fiy0             = 0.0;
 147         fiz0             = 0.0;
 148         fix1             = 0.0;
 149         fiy1             = 0.0;
 150         fiz1             = 0.0;
 151         fix2             = 0.0;
 152         fiy2             = 0.0;
 153         fiz2             = 0.0;
 154
 155         /* Reset potential sums */
 156         velecsum         = 0.0;
 157         vvdwsum          = 0.0;
 158
 159         /* Start inner kernel loop */
 160         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 161         {
 162             /* Get j neighbor index, and coordinate index */
 163             jnr              = jjnr[jidx];
 164             j_coord_offset   = DIM*jnr;
 165
 166             /* load j atom coordinates */
 167             jx0              = x[j_coord_offset+DIM*0+XX];
 168             jy0              = x[j_coord_offset+DIM*0+YY];
 169             jz0              = x[j_coord_offset+DIM*0+ZZ];
 170
 171             /* Calculate displacement vector */
 172             dx00             = ix0 - jx0;
 173             dy00             = iy0 - jy0;
 174             dz00             = iz0 - jz0;
 175             dx10             = ix1 - jx0;
 176             dy10             = iy1 - jy0;
 177             dz10             = iz1 - jz0;
 178             dx20             = ix2 - jx0;
 179             dy20             = iy2 - jy0;
 180             dz20             = iz2 - jz0;
 181
 182             /* Calculate squared distance and things based on it */
 183             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 184             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 185             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 186
 187             rinv00           = gmx_invsqrt(rsq00);
 188             rinv10           = gmx_invsqrt(rsq10);
 189             rinv20           = gmx_invsqrt(rsq20);
 190
 191             rinvsq00         = rinv00*rinv00;
 192             rinvsq10         = rinv10*rinv10;
 193             rinvsq20         = rinv20*rinv20;
 194
 195             /* Load parameters for j particles */
 196             jq0              = charge[jnr+0];
 197             vdwjidx0         = 2*vdwtype[jnr+0];
 198
 199             /**************************
 200              * CALCULATE INTERACTIONS *
 201              **************************/
 202
 203             qq00             = iq0*jq0;
 204             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 205             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 206
 207             /* COULOMB ELECTROSTATICS */
 208             velec            = qq00*rinv00;
 209             felec            = velec*rinvsq00;
 210
 211             /* LENNARD-JONES DISPERSION/REPULSION */
 212
 213             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 214             vvdw6            = c6_00*rinvsix;
 215             vvdw12           = c12_00*rinvsix*rinvsix;
 216             vvdw             = vvdw12*(1.0/12.0) - vvdw6*(1.0/6.0);
 217             fvdw             = (vvdw12-vvdw6)*rinvsq00;
 218
 219             /* Update potential sums from outer loop */
 220             velecsum        += velec;
 221             vvdwsum         += vvdw;
 222
 223             fscal            = felec+fvdw;
 224
 225             /* Calculate temporary vectorial force */
 226             tx               = fscal*dx00;
 227             ty               = fscal*dy00;
 228             tz               = fscal*dz00;
 229
 230             /* Update vectorial force */
 231             fix0            += tx;
 232             fiy0            += ty;
 233             fiz0            += tz;
 234             f[j_coord_offset+DIM*0+XX] -= tx;
 235             f[j_coord_offset+DIM*0+YY] -= ty;
 236             f[j_coord_offset+DIM*0+ZZ] -= tz;
 237
 238             /**************************
 239              * CALCULATE INTERACTIONS *
 240              **************************/
 241
 242             qq10             = iq1*jq0;
 243
 244             /* COULOMB ELECTROSTATICS */
 245             velec            = qq10*rinv10;
 246             felec            = velec*rinvsq10;
 247
 248             /* Update potential sums from outer loop */
 249             velecsum        += velec;
 250
 251             fscal            = felec;
 252
 253             /* Calculate temporary vectorial force */
 254             tx               = fscal*dx10;
 255             ty               = fscal*dy10;
 256             tz               = fscal*dz10;
 257
 258             /* Update vectorial force */
 259             fix1            += tx;
 260             fiy1            += ty;
 261             fiz1            += tz;
 262             f[j_coord_offset+DIM*0+XX] -= tx;
 263             f[j_coord_offset+DIM*0+YY] -= ty;
 264             f[j_coord_offset+DIM*0+ZZ] -= tz;
 265
 266             /**************************
 267              * CALCULATE INTERACTIONS *
 268              **************************/
 269
 270             qq20             = iq2*jq0;
 271
 272             /* COULOMB ELECTROSTATICS */
 273             velec            = qq20*rinv20;
 274             felec            = velec*rinvsq20;
 275
 276             /* Update potential sums from outer loop */
 277             velecsum        += velec;
 278
 279             fscal            = felec;
 280
 281             /* Calculate temporary vectorial force */
 282             tx               = fscal*dx20;
 283             ty               = fscal*dy20;
 284             tz               = fscal*dz20;
 285
 286             /* Update vectorial force */
 287             fix2            += tx;
 288             fiy2            += ty;
 289             fiz2            += tz;
 290             f[j_coord_offset+DIM*0+XX] -= tx;
 291             f[j_coord_offset+DIM*0+YY] -= ty;
 292             f[j_coord_offset+DIM*0+ZZ] -= tz;
 293
 294             /* Inner loop uses 96 flops */
 295         }
 296         /* End of innermost loop */
 297
 298         tx = ty = tz = 0;
 299         f[i_coord_offset+DIM*0+XX] += fix0;
 300         f[i_coord_offset+DIM*0+YY] += fiy0;
 301         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 302         tx                         += fix0;
 303         ty                         += fiy0;
 304         tz                         += fiz0;
 305         f[i_coord_offset+DIM*1+XX] += fix1;
 306         f[i_coord_offset+DIM*1+YY] += fiy1;
 307         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 308         tx                         += fix1;
 309         ty                         += fiy1;
 310         tz                         += fiz1;
 311         f[i_coord_offset+DIM*2+XX] += fix2;
 312         f[i_coord_offset+DIM*2+YY] += fiy2;
 313         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 314         tx                         += fix2;
 315         ty                         += fiy2;
 316         tz                         += fiz2;
 317         fshift[i_shift_offset+XX]  += tx;
 318         fshift[i_shift_offset+YY]  += ty;
 319         fshift[i_shift_offset+ZZ]  += tz;
 320
 321         ggid                        = gid[iidx];
 322         /* Update potential energies */
 323         kernel_data->energygrp_elec[ggid] += velecsum;
 324         kernel_data->energygrp_vdw[ggid] += vvdwsum;
 325
 326         /* Increment number of inner iterations */
 327         inneriter                  += j_index_end - j_index_start;
 328
 329         /* Outer loop uses 32 flops */
 330     }
 331
 332     /* Increment number of outer iterations */
 333     outeriter        += nri;
 334
 335     /* Update outer/inner flops */
 336
 337     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W3_VF,outeriter*32 + inneriter*96);
 338 }
 339 /*
 340  * Gromacs nonbonded kernel:   nb_kernel_ElecCoul_VdwLJ_GeomW3P1_F_c
 341  * Electrostatics interaction: Coulomb
 342  * VdW interaction:            LennardJones
 343  * Geometry:                   Water3-Particle
 344  * Calculate force/pot:        Force
 345  */
 346 void
 347 nb_kernel_ElecCoul_VdwLJ_GeomW3P1_F_c
 348                     (t_nblist                    * gmx_restrict       nlist,
 349                      rvec                        * gmx_restrict          xx,
 350                      rvec                        * gmx_restrict          ff,
 351                      t_forcerec                  * gmx_restrict          fr,
 352                      t_mdatoms                   * gmx_restrict     mdatoms,
 353                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 354                      t_nrnb                      * gmx_restrict        nrnb)
 355 {
 356     int              i_shift_offset,i_coord_offset,j_coord_offset;
 357     int              j_index_start,j_index_end;
 358     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 359     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 360     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 361     real             *shiftvec,*fshift,*x,*f;
 362     int              vdwioffset0;
 363     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 364     int              vdwioffset1;
 365     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 366     int              vdwioffset2;
 367     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 368     int              vdwjidx0;
 369     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 370     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
 371     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
 372     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
 373     real             velec,felec,velecsum,facel,crf,krf,krf2;
 374     real             *charge;
 375     int              nvdwtype;
 376     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
 377     int              *vdwtype;
 378     real             *vdwparam;
 379
 380     x                = xx[0];
 381     f                = ff[0];
 382
 383     nri              = nlist->nri;
 384     iinr             = nlist->iinr;
 385     jindex           = nlist->jindex;
 386     jjnr             = nlist->jjnr;
 387     shiftidx         = nlist->shift;
 388     gid              = nlist->gid;
 389     shiftvec         = fr->shift_vec[0];
 390     fshift           = fr->fshift[0];
 391     facel            = fr->epsfac;
 392     charge           = mdatoms->chargeA;
 393     nvdwtype         = fr->ntype;
 394     vdwparam         = fr->nbfp;
 395     vdwtype          = mdatoms->typeA;
 396
 397     /* Setup water-specific parameters */
 398     inr              = nlist->iinr[0];
 399     iq0              = facel*charge[inr+0];
 400     iq1              = facel*charge[inr+1];
 401     iq2              = facel*charge[inr+2];
 402     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 403
 404     outeriter        = 0;
 405     inneriter        = 0;
 406
 407     /* Start outer loop over neighborlists */
 408     for(iidx=0; iidx<nri; iidx++)
 409     {
 410         /* Load shift vector for this list */
 411         i_shift_offset   = DIM*shiftidx[iidx];
 412         shX              = shiftvec[i_shift_offset+XX];
 413         shY              = shiftvec[i_shift_offset+YY];
 414         shZ              = shiftvec[i_shift_offset+ZZ];
 415
 416         /* Load limits for loop over neighbors */
 417         j_index_start    = jindex[iidx];
 418         j_index_end      = jindex[iidx+1];
 419
 420         /* Get outer coordinate index */
 421         inr              = iinr[iidx];
 422         i_coord_offset   = DIM*inr;
 423
 424         /* Load i particle coords and add shift vector */
 425         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 426         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 427         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 428         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 429         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 430         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 431         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 432         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 433         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 434
 435         fix0             = 0.0;
 436         fiy0             = 0.0;
 437         fiz0             = 0.0;
 438         fix1             = 0.0;
 439         fiy1             = 0.0;
 440         fiz1             = 0.0;
 441         fix2             = 0.0;
 442         fiy2             = 0.0;
 443         fiz2             = 0.0;
 444
 445         /* Start inner kernel loop */
 446         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 447         {
 448             /* Get j neighbor index, and coordinate index */
 449             jnr              = jjnr[jidx];
 450             j_coord_offset   = DIM*jnr;
 451
 452             /* load j atom coordinates */
 453             jx0              = x[j_coord_offset+DIM*0+XX];
 454             jy0              = x[j_coord_offset+DIM*0+YY];
 455             jz0              = x[j_coord_offset+DIM*0+ZZ];
 456
 457             /* Calculate displacement vector */
 458             dx00             = ix0 - jx0;
 459             dy00             = iy0 - jy0;
 460             dz00             = iz0 - jz0;
 461             dx10             = ix1 - jx0;
 462             dy10             = iy1 - jy0;
 463             dz10             = iz1 - jz0;
 464             dx20             = ix2 - jx0;
 465             dy20             = iy2 - jy0;
 466             dz20             = iz2 - jz0;
 467
 468             /* Calculate squared distance and things based on it */
 469             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 470             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 471             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 472
 473             rinv00           = gmx_invsqrt(rsq00);
 474             rinv10           = gmx_invsqrt(rsq10);
 475             rinv20           = gmx_invsqrt(rsq20);
 476
 477             rinvsq00         = rinv00*rinv00;
 478             rinvsq10         = rinv10*rinv10;
 479             rinvsq20         = rinv20*rinv20;
 480
 481             /* Load parameters for j particles */
 482             jq0              = charge[jnr+0];
 483             vdwjidx0         = 2*vdwtype[jnr+0];
 484
 485             /**************************
 486              * CALCULATE INTERACTIONS *
 487              **************************/
 488
 489             qq00             = iq0*jq0;
 490             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 491             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 492
 493             /* COULOMB ELECTROSTATICS */
 494             velec            = qq00*rinv00;
 495             felec            = velec*rinvsq00;
 496
 497             /* LENNARD-JONES DISPERSION/REPULSION */
 498
 499             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 500             fvdw             = (c12_00*rinvsix-c6_00)*rinvsix*rinvsq00;
 501
 502             fscal            = felec+fvdw;
 503
 504             /* Calculate temporary vectorial force */
 505             tx               = fscal*dx00;
 506             ty               = fscal*dy00;
 507             tz               = fscal*dz00;
 508
 509             /* Update vectorial force */
 510             fix0            += tx;
 511             fiy0            += ty;
 512             fiz0            += tz;
 513             f[j_coord_offset+DIM*0+XX] -= tx;
 514             f[j_coord_offset+DIM*0+YY] -= ty;
 515             f[j_coord_offset+DIM*0+ZZ] -= tz;
 516
 517             /**************************
 518              * CALCULATE INTERACTIONS *
 519              **************************/
 520
 521             qq10             = iq1*jq0;
 522
 523             /* COULOMB ELECTROSTATICS */
 524             velec            = qq10*rinv10;
 525             felec            = velec*rinvsq10;
 526
 527             fscal            = felec;
 528
 529             /* Calculate temporary vectorial force */
 530             tx               = fscal*dx10;
 531             ty               = fscal*dy10;
 532             tz               = fscal*dz10;
 533
 534             /* Update vectorial force */
 535             fix1            += tx;
 536             fiy1            += ty;
 537             fiz1            += tz;
 538             f[j_coord_offset+DIM*0+XX] -= tx;
 539             f[j_coord_offset+DIM*0+YY] -= ty;
 540             f[j_coord_offset+DIM*0+ZZ] -= tz;
 541
 542             /**************************
 543              * CALCULATE INTERACTIONS *
 544              **************************/
 545
 546             qq20             = iq2*jq0;
 547
 548             /* COULOMB ELECTROSTATICS */
 549             velec            = qq20*rinv20;
 550             felec            = velec*rinvsq20;
 551
 552             fscal            = felec;
 553
 554             /* Calculate temporary vectorial force */
 555             tx               = fscal*dx20;
 556             ty               = fscal*dy20;
 557             tz               = fscal*dz20;
 558
 559             /* Update vectorial force */
 560             fix2            += tx;
 561             fiy2            += ty;
 562             fiz2            += tz;
 563             f[j_coord_offset+DIM*0+XX] -= tx;
 564             f[j_coord_offset+DIM*0+YY] -= ty;
 565             f[j_coord_offset+DIM*0+ZZ] -= tz;
 566
 567             /* Inner loop uses 88 flops */
 568         }
 569         /* End of innermost loop */
 570
 571         tx = ty = tz = 0;
 572         f[i_coord_offset+DIM*0+XX] += fix0;
 573         f[i_coord_offset+DIM*0+YY] += fiy0;
 574         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 575         tx                         += fix0;
 576         ty                         += fiy0;
 577         tz                         += fiz0;
 578         f[i_coord_offset+DIM*1+XX] += fix1;
 579         f[i_coord_offset+DIM*1+YY] += fiy1;
 580         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 581         tx                         += fix1;
 582         ty                         += fiy1;
 583         tz                         += fiz1;
 584         f[i_coord_offset+DIM*2+XX] += fix2;
 585         f[i_coord_offset+DIM*2+YY] += fiy2;
 586         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 587         tx                         += fix2;
 588         ty                         += fiy2;
 589         tz                         += fiz2;
 590         fshift[i_shift_offset+XX]  += tx;
 591         fshift[i_shift_offset+YY]  += ty;
 592         fshift[i_shift_offset+ZZ]  += tz;
 593
 594         /* Increment number of inner iterations */
 595         inneriter                  += j_index_end - j_index_start;
 596
 597         /* Outer loop uses 30 flops */
 598     }
 599
 600     /* Increment number of outer iterations */
 601     outeriter        += nri;
 602
 603     /* Update outer/inner flops */
 604
 605     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W3_F,outeriter*30 + inneriter*88);
 606 }