src/gromacs/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecEw_VdwNone_GeomW4P1_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.
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  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_ElecEw_VdwNone_GeomW4P1_VF_c
  51  * Electrostatics interaction: Ewald
  52  * VdW interaction:            None
  53  * Geometry:                   Water4-Particle
  54  * Calculate force/pot:        PotentialAndForce
  55  */
  56 void
  57 nb_kernel_ElecEw_VdwNone_GeomW4P1_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              vdwioffset1;
  73     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
  74     int              vdwioffset2;
  75     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
  76     int              vdwioffset3;
  77     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
  78     int              vdwjidx0;
  79     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  80     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
  81     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
  82     real             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
  83     real             velec,felec,velecsum,facel,crf,krf,krf2;
  84     real             *charge;
  85     int              ewitab;
  86     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
  87     real             *ewtab;
  88
  89     x                = xx[0];
  90     f                = ff[0];
  91
  92     nri              = nlist->nri;
  93     iinr             = nlist->iinr;
  94     jindex           = nlist->jindex;
  95     jjnr             = nlist->jjnr;
  96     shiftidx         = nlist->shift;
  97     gid              = nlist->gid;
  98     shiftvec         = fr->shift_vec[0];
  99     fshift           = fr->fshift[0];
 100     facel            = fr->epsfac;
 101     charge           = mdatoms->chargeA;
 102
 103     sh_ewald         = fr->ic->sh_ewald;
 104     ewtab            = fr->ic->tabq_coul_FDV0;
 105     ewtabscale       = fr->ic->tabq_scale;
 106     ewtabhalfspace   = 0.5/ewtabscale;
 107
 108     /* Setup water-specific parameters */
 109     inr              = nlist->iinr[0];
 110     iq1              = facel*charge[inr+1];
 111     iq2              = facel*charge[inr+2];
 112     iq3              = facel*charge[inr+3];
 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         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 136         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 137         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 138         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 139         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 140         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 141         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 142         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 143         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 144
 145         fix1             = 0.0;
 146         fiy1             = 0.0;
 147         fiz1             = 0.0;
 148         fix2             = 0.0;
 149         fiy2             = 0.0;
 150         fiz2             = 0.0;
 151         fix3             = 0.0;
 152         fiy3             = 0.0;
 153         fiz3             = 0.0;
 154
 155         /* Reset potential sums */
 156         velecsum         = 0.0;
 157
 158         /* Start inner kernel loop */
 159         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 160         {
 161             /* Get j neighbor index, and coordinate index */
 162             jnr              = jjnr[jidx];
 163             j_coord_offset   = DIM*jnr;
 164
 165             /* load j atom coordinates */
 166             jx0              = x[j_coord_offset+DIM*0+XX];
 167             jy0              = x[j_coord_offset+DIM*0+YY];
 168             jz0              = x[j_coord_offset+DIM*0+ZZ];
 169
 170             /* Calculate displacement vector */
 171             dx10             = ix1 - jx0;
 172             dy10             = iy1 - jy0;
 173             dz10             = iz1 - jz0;
 174             dx20             = ix2 - jx0;
 175             dy20             = iy2 - jy0;
 176             dz20             = iz2 - jz0;
 177             dx30             = ix3 - jx0;
 178             dy30             = iy3 - jy0;
 179             dz30             = iz3 - jz0;
 180
 181             /* Calculate squared distance and things based on it */
 182             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 183             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 184             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 185
 186             rinv10           = gmx_invsqrt(rsq10);
 187             rinv20           = gmx_invsqrt(rsq20);
 188             rinv30           = gmx_invsqrt(rsq30);
 189
 190             rinvsq10         = rinv10*rinv10;
 191             rinvsq20         = rinv20*rinv20;
 192             rinvsq30         = rinv30*rinv30;
 193
 194             /* Load parameters for j particles */
 195             jq0              = charge[jnr+0];
 196
 197             /**************************
 198              * CALCULATE INTERACTIONS *
 199              **************************/
 200
 201             r10              = rsq10*rinv10;
 202
 203             qq10             = iq1*jq0;
 204
 205             /* EWALD ELECTROSTATICS */
 206
 207             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 208             ewrt             = r10*ewtabscale;
 209             ewitab           = ewrt;
 210             eweps            = ewrt-ewitab;
 211             ewitab           = 4*ewitab;
 212             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 213             velec            = qq10*(rinv10-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 214             felec            = qq10*rinv10*(rinvsq10-felec);
 215
 216             /* Update potential sums from outer loop */
 217             velecsum        += velec;
 218
 219             fscal            = felec;
 220
 221             /* Calculate temporary vectorial force */
 222             tx               = fscal*dx10;
 223             ty               = fscal*dy10;
 224             tz               = fscal*dz10;
 225
 226             /* Update vectorial force */
 227             fix1            += tx;
 228             fiy1            += ty;
 229             fiz1            += tz;
 230             f[j_coord_offset+DIM*0+XX] -= tx;
 231             f[j_coord_offset+DIM*0+YY] -= ty;
 232             f[j_coord_offset+DIM*0+ZZ] -= tz;
 233
 234             /**************************
 235              * CALCULATE INTERACTIONS *
 236              **************************/
 237
 238             r20              = rsq20*rinv20;
 239
 240             qq20             = iq2*jq0;
 241
 242             /* EWALD ELECTROSTATICS */
 243
 244             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 245             ewrt             = r20*ewtabscale;
 246             ewitab           = ewrt;
 247             eweps            = ewrt-ewitab;
 248             ewitab           = 4*ewitab;
 249             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 250             velec            = qq20*(rinv20-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 251             felec            = qq20*rinv20*(rinvsq20-felec);
 252
 253             /* Update potential sums from outer loop */
 254             velecsum        += velec;
 255
 256             fscal            = felec;
 257
 258             /* Calculate temporary vectorial force */
 259             tx               = fscal*dx20;
 260             ty               = fscal*dy20;
 261             tz               = fscal*dz20;
 262
 263             /* Update vectorial force */
 264             fix2            += tx;
 265             fiy2            += ty;
 266             fiz2            += tz;
 267             f[j_coord_offset+DIM*0+XX] -= tx;
 268             f[j_coord_offset+DIM*0+YY] -= ty;
 269             f[j_coord_offset+DIM*0+ZZ] -= tz;
 270
 271             /**************************
 272              * CALCULATE INTERACTIONS *
 273              **************************/
 274
 275             r30              = rsq30*rinv30;
 276
 277             qq30             = iq3*jq0;
 278
 279             /* EWALD ELECTROSTATICS */
 280
 281             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 282             ewrt             = r30*ewtabscale;
 283             ewitab           = ewrt;
 284             eweps            = ewrt-ewitab;
 285             ewitab           = 4*ewitab;
 286             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 287             velec            = qq30*(rinv30-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 288             felec            = qq30*rinv30*(rinvsq30-felec);
 289
 290             /* Update potential sums from outer loop */
 291             velecsum        += velec;
 292
 293             fscal            = felec;
 294
 295             /* Calculate temporary vectorial force */
 296             tx               = fscal*dx30;
 297             ty               = fscal*dy30;
 298             tz               = fscal*dz30;
 299
 300             /* Update vectorial force */
 301             fix3            += tx;
 302             fiy3            += ty;
 303             fiz3            += tz;
 304             f[j_coord_offset+DIM*0+XX] -= tx;
 305             f[j_coord_offset+DIM*0+YY] -= ty;
 306             f[j_coord_offset+DIM*0+ZZ] -= tz;
 307
 308             /* Inner loop uses 123 flops */
 309         }
 310         /* End of innermost loop */
 311
 312         tx = ty = tz = 0;
 313         f[i_coord_offset+DIM*1+XX] += fix1;
 314         f[i_coord_offset+DIM*1+YY] += fiy1;
 315         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 316         tx                         += fix1;
 317         ty                         += fiy1;
 318         tz                         += fiz1;
 319         f[i_coord_offset+DIM*2+XX] += fix2;
 320         f[i_coord_offset+DIM*2+YY] += fiy2;
 321         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 322         tx                         += fix2;
 323         ty                         += fiy2;
 324         tz                         += fiz2;
 325         f[i_coord_offset+DIM*3+XX] += fix3;
 326         f[i_coord_offset+DIM*3+YY] += fiy3;
 327         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 328         tx                         += fix3;
 329         ty                         += fiy3;
 330         tz                         += fiz3;
 331         fshift[i_shift_offset+XX]  += tx;
 332         fshift[i_shift_offset+YY]  += ty;
 333         fshift[i_shift_offset+ZZ]  += tz;
 334
 335         ggid                        = gid[iidx];
 336         /* Update potential energies */
 337         kernel_data->energygrp_elec[ggid] += velecsum;
 338
 339         /* Increment number of inner iterations */
 340         inneriter                  += j_index_end - j_index_start;
 341
 342         /* Outer loop uses 31 flops */
 343     }
 344
 345     /* Increment number of outer iterations */
 346     outeriter        += nri;
 347
 348     /* Update outer/inner flops */
 349
 350     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_W4_VF,outeriter*31 + inneriter*123);
 351 }
 352 /*
 353  * Gromacs nonbonded kernel:   nb_kernel_ElecEw_VdwNone_GeomW4P1_F_c
 354  * Electrostatics interaction: Ewald
 355  * VdW interaction:            None
 356  * Geometry:                   Water4-Particle
 357  * Calculate force/pot:        Force
 358  */
 359 void
 360 nb_kernel_ElecEw_VdwNone_GeomW4P1_F_c
 361                     (t_nblist                    * gmx_restrict       nlist,
 362                      rvec                        * gmx_restrict          xx,
 363                      rvec                        * gmx_restrict          ff,
 364                      t_forcerec                  * gmx_restrict          fr,
 365                      t_mdatoms                   * gmx_restrict     mdatoms,
 366                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 367                      t_nrnb                      * gmx_restrict        nrnb)
 368 {
 369     int              i_shift_offset,i_coord_offset,j_coord_offset;
 370     int              j_index_start,j_index_end;
 371     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 372     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 373     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 374     real             *shiftvec,*fshift,*x,*f;
 375     int              vdwioffset1;
 376     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 377     int              vdwioffset2;
 378     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 379     int              vdwioffset3;
 380     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
 381     int              vdwjidx0;
 382     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 383     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
 384     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
 385     real             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
 386     real             velec,felec,velecsum,facel,crf,krf,krf2;
 387     real             *charge;
 388     int              ewitab;
 389     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
 390     real             *ewtab;
 391
 392     x                = xx[0];
 393     f                = ff[0];
 394
 395     nri              = nlist->nri;
 396     iinr             = nlist->iinr;
 397     jindex           = nlist->jindex;
 398     jjnr             = nlist->jjnr;
 399     shiftidx         = nlist->shift;
 400     gid              = nlist->gid;
 401     shiftvec         = fr->shift_vec[0];
 402     fshift           = fr->fshift[0];
 403     facel            = fr->epsfac;
 404     charge           = mdatoms->chargeA;
 405
 406     sh_ewald         = fr->ic->sh_ewald;
 407     ewtab            = fr->ic->tabq_coul_F;
 408     ewtabscale       = fr->ic->tabq_scale;
 409     ewtabhalfspace   = 0.5/ewtabscale;
 410
 411     /* Setup water-specific parameters */
 412     inr              = nlist->iinr[0];
 413     iq1              = facel*charge[inr+1];
 414     iq2              = facel*charge[inr+2];
 415     iq3              = facel*charge[inr+3];
 416
 417     outeriter        = 0;
 418     inneriter        = 0;
 419
 420     /* Start outer loop over neighborlists */
 421     for(iidx=0; iidx<nri; iidx++)
 422     {
 423         /* Load shift vector for this list */
 424         i_shift_offset   = DIM*shiftidx[iidx];
 425         shX              = shiftvec[i_shift_offset+XX];
 426         shY              = shiftvec[i_shift_offset+YY];
 427         shZ              = shiftvec[i_shift_offset+ZZ];
 428
 429         /* Load limits for loop over neighbors */
 430         j_index_start    = jindex[iidx];
 431         j_index_end      = jindex[iidx+1];
 432
 433         /* Get outer coordinate index */
 434         inr              = iinr[iidx];
 435         i_coord_offset   = DIM*inr;
 436
 437         /* Load i particle coords and add shift vector */
 438         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 439         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 440         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 441         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 442         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 443         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 444         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 445         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 446         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 447
 448         fix1             = 0.0;
 449         fiy1             = 0.0;
 450         fiz1             = 0.0;
 451         fix2             = 0.0;
 452         fiy2             = 0.0;
 453         fiz2             = 0.0;
 454         fix3             = 0.0;
 455         fiy3             = 0.0;
 456         fiz3             = 0.0;
 457
 458         /* Start inner kernel loop */
 459         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 460         {
 461             /* Get j neighbor index, and coordinate index */
 462             jnr              = jjnr[jidx];
 463             j_coord_offset   = DIM*jnr;
 464
 465             /* load j atom coordinates */
 466             jx0              = x[j_coord_offset+DIM*0+XX];
 467             jy0              = x[j_coord_offset+DIM*0+YY];
 468             jz0              = x[j_coord_offset+DIM*0+ZZ];
 469
 470             /* Calculate displacement vector */
 471             dx10             = ix1 - jx0;
 472             dy10             = iy1 - jy0;
 473             dz10             = iz1 - jz0;
 474             dx20             = ix2 - jx0;
 475             dy20             = iy2 - jy0;
 476             dz20             = iz2 - jz0;
 477             dx30             = ix3 - jx0;
 478             dy30             = iy3 - jy0;
 479             dz30             = iz3 - jz0;
 480
 481             /* Calculate squared distance and things based on it */
 482             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 483             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 484             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 485
 486             rinv10           = gmx_invsqrt(rsq10);
 487             rinv20           = gmx_invsqrt(rsq20);
 488             rinv30           = gmx_invsqrt(rsq30);
 489
 490             rinvsq10         = rinv10*rinv10;
 491             rinvsq20         = rinv20*rinv20;
 492             rinvsq30         = rinv30*rinv30;
 493
 494             /* Load parameters for j particles */
 495             jq0              = charge[jnr+0];
 496
 497             /**************************
 498              * CALCULATE INTERACTIONS *
 499              **************************/
 500
 501             r10              = rsq10*rinv10;
 502
 503             qq10             = iq1*jq0;
 504
 505             /* EWALD ELECTROSTATICS */
 506
 507             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 508             ewrt             = r10*ewtabscale;
 509             ewitab           = ewrt;
 510             eweps            = ewrt-ewitab;
 511             felec            = (1.0-eweps)*ewtab[ewitab]+eweps*ewtab[ewitab+1];
 512             felec            = qq10*rinv10*(rinvsq10-felec);
 513
 514             fscal            = felec;
 515
 516             /* Calculate temporary vectorial force */
 517             tx               = fscal*dx10;
 518             ty               = fscal*dy10;
 519             tz               = fscal*dz10;
 520
 521             /* Update vectorial force */
 522             fix1            += tx;
 523             fiy1            += ty;
 524             fiz1            += tz;
 525             f[j_coord_offset+DIM*0+XX] -= tx;
 526             f[j_coord_offset+DIM*0+YY] -= ty;
 527             f[j_coord_offset+DIM*0+ZZ] -= tz;
 528
 529             /**************************
 530              * CALCULATE INTERACTIONS *
 531              **************************/
 532
 533             r20              = rsq20*rinv20;
 534
 535             qq20             = iq2*jq0;
 536
 537             /* EWALD ELECTROSTATICS */
 538
 539             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 540             ewrt             = r20*ewtabscale;
 541             ewitab           = ewrt;
 542             eweps            = ewrt-ewitab;
 543             felec            = (1.0-eweps)*ewtab[ewitab]+eweps*ewtab[ewitab+1];
 544             felec            = qq20*rinv20*(rinvsq20-felec);
 545
 546             fscal            = felec;
 547
 548             /* Calculate temporary vectorial force */
 549             tx               = fscal*dx20;
 550             ty               = fscal*dy20;
 551             tz               = fscal*dz20;
 552
 553             /* Update vectorial force */
 554             fix2            += tx;
 555             fiy2            += ty;
 556             fiz2            += tz;
 557             f[j_coord_offset+DIM*0+XX] -= tx;
 558             f[j_coord_offset+DIM*0+YY] -= ty;
 559             f[j_coord_offset+DIM*0+ZZ] -= tz;
 560
 561             /**************************
 562              * CALCULATE INTERACTIONS *
 563              **************************/
 564
 565             r30              = rsq30*rinv30;
 566
 567             qq30             = iq3*jq0;
 568
 569             /* EWALD ELECTROSTATICS */
 570
 571             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 572             ewrt             = r30*ewtabscale;
 573             ewitab           = ewrt;
 574             eweps            = ewrt-ewitab;
 575             felec            = (1.0-eweps)*ewtab[ewitab]+eweps*ewtab[ewitab+1];
 576             felec            = qq30*rinv30*(rinvsq30-felec);
 577
 578             fscal            = felec;
 579
 580             /* Calculate temporary vectorial force */
 581             tx               = fscal*dx30;
 582             ty               = fscal*dy30;
 583             tz               = fscal*dz30;
 584
 585             /* Update vectorial force */
 586             fix3            += tx;
 587             fiy3            += ty;
 588             fiz3            += tz;
 589             f[j_coord_offset+DIM*0+XX] -= tx;
 590             f[j_coord_offset+DIM*0+YY] -= ty;
 591             f[j_coord_offset+DIM*0+ZZ] -= tz;
 592
 593             /* Inner loop uses 102 flops */
 594         }
 595         /* End of innermost loop */
 596
 597         tx = ty = tz = 0;
 598         f[i_coord_offset+DIM*1+XX] += fix1;
 599         f[i_coord_offset+DIM*1+YY] += fiy1;
 600         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 601         tx                         += fix1;
 602         ty                         += fiy1;
 603         tz                         += fiz1;
 604         f[i_coord_offset+DIM*2+XX] += fix2;
 605         f[i_coord_offset+DIM*2+YY] += fiy2;
 606         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 607         tx                         += fix2;
 608         ty                         += fiy2;
 609         tz                         += fiz2;
 610         f[i_coord_offset+DIM*3+XX] += fix3;
 611         f[i_coord_offset+DIM*3+YY] += fiy3;
 612         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 613         tx                         += fix3;
 614         ty                         += fiy3;
 615         tz                         += fiz3;
 616         fshift[i_shift_offset+XX]  += tx;
 617         fshift[i_shift_offset+YY]  += ty;
 618         fshift[i_shift_offset+ZZ]  += tz;
 619
 620         /* Increment number of inner iterations */
 621         inneriter                  += j_index_end - j_index_start;
 622
 623         /* Outer loop uses 30 flops */
 624     }
 625
 626     /* Increment number of outer iterations */
 627     outeriter        += nri;
 628
 629     /* Update outer/inner flops */
 630
 631     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_W4_F,outeriter*30 + inneriter*102);
 632 }