src/gromacs/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecRFCut_VdwBhamSh_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.
  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 c kernel generator.
  37  */
  38 #include "config.h"
  39
  40 #include <math.h>
  41
  42 #include "../nb_kernel.h"
  43 #include "gromacs/legacyheaders/types/simple.h"
  44 #include "gromacs/math/vec.h"
  45 #include "gromacs/legacyheaders/nrnb.h"
  46
  47 /*
  48  * Gromacs nonbonded kernel:   nb_kernel_ElecRFCut_VdwBhamSh_GeomW4P1_VF_c
  49  * Electrostatics interaction: ReactionField
  50  * VdW interaction:            Buckingham
  51  * Geometry:                   Water4-Particle
  52  * Calculate force/pot:        PotentialAndForce
  53  */
  54 void
  55 nb_kernel_ElecRFCut_VdwBhamSh_GeomW4P1_VF_c
  56                     (t_nblist                    * gmx_restrict       nlist,
  57                      rvec                        * gmx_restrict          xx,
  58                      rvec                        * gmx_restrict          ff,
  59                      t_forcerec                  * gmx_restrict          fr,
  60                      t_mdatoms                   * gmx_restrict     mdatoms,
  61                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
  62                      t_nrnb                      * gmx_restrict        nrnb)
  63 {
  64     int              i_shift_offset,i_coord_offset,j_coord_offset;
  65     int              j_index_start,j_index_end;
  66     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
  67     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
  68     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  69     real             *shiftvec,*fshift,*x,*f;
  70     int              vdwioffset0;
  71     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  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             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             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
  84     real             velec,felec,velecsum,facel,crf,krf,krf2;
  85     real             *charge;
  86     int              nvdwtype;
  87     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
  88     int              *vdwtype;
  89     real             *vdwparam;
  90
  91     x                = xx[0];
  92     f                = ff[0];
  93
  94     nri              = nlist->nri;
  95     iinr             = nlist->iinr;
  96     jindex           = nlist->jindex;
  97     jjnr             = nlist->jjnr;
  98     shiftidx         = nlist->shift;
  99     gid              = nlist->gid;
 100     shiftvec         = fr->shift_vec[0];
 101     fshift           = fr->fshift[0];
 102     facel            = fr->epsfac;
 103     charge           = mdatoms->chargeA;
 104     krf              = fr->ic->k_rf;
 105     krf2             = krf*2.0;
 106     crf              = fr->ic->c_rf;
 107     nvdwtype         = fr->ntype;
 108     vdwparam         = fr->nbfp;
 109     vdwtype          = mdatoms->typeA;
 110
 111     /* Setup water-specific parameters */
 112     inr              = nlist->iinr[0];
 113     iq1              = facel*charge[inr+1];
 114     iq2              = facel*charge[inr+2];
 115     iq3              = facel*charge[inr+3];
 116     vdwioffset0      = 3*nvdwtype*vdwtype[inr+0];
 117
 118     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 119     rcutoff          = fr->rcoulomb;
 120     rcutoff2         = rcutoff*rcutoff;
 121
 122     sh_vdw_invrcut6  = fr->ic->sh_invrc6;
 123     rvdw             = fr->rvdw;
 124
 125     outeriter        = 0;
 126     inneriter        = 0;
 127
 128     /* Start outer loop over neighborlists */
 129     for(iidx=0; iidx<nri; iidx++)
 130     {
 131         /* Load shift vector for this list */
 132         i_shift_offset   = DIM*shiftidx[iidx];
 133         shX              = shiftvec[i_shift_offset+XX];
 134         shY              = shiftvec[i_shift_offset+YY];
 135         shZ              = shiftvec[i_shift_offset+ZZ];
 136
 137         /* Load limits for loop over neighbors */
 138         j_index_start    = jindex[iidx];
 139         j_index_end      = jindex[iidx+1];
 140
 141         /* Get outer coordinate index */
 142         inr              = iinr[iidx];
 143         i_coord_offset   = DIM*inr;
 144
 145         /* Load i particle coords and add shift vector */
 146         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 147         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 148         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 149         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 150         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 151         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 152         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 153         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 154         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 155         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 156         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 157         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 158
 159         fix0             = 0.0;
 160         fiy0             = 0.0;
 161         fiz0             = 0.0;
 162         fix1             = 0.0;
 163         fiy1             = 0.0;
 164         fiz1             = 0.0;
 165         fix2             = 0.0;
 166         fiy2             = 0.0;
 167         fiz2             = 0.0;
 168         fix3             = 0.0;
 169         fiy3             = 0.0;
 170         fiz3             = 0.0;
 171
 172         /* Reset potential sums */
 173         velecsum         = 0.0;
 174         vvdwsum          = 0.0;
 175
 176         /* Start inner kernel loop */
 177         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 178         {
 179             /* Get j neighbor index, and coordinate index */
 180             jnr              = jjnr[jidx];
 181             j_coord_offset   = DIM*jnr;
 182
 183             /* load j atom coordinates */
 184             jx0              = x[j_coord_offset+DIM*0+XX];
 185             jy0              = x[j_coord_offset+DIM*0+YY];
 186             jz0              = x[j_coord_offset+DIM*0+ZZ];
 187
 188             /* Calculate displacement vector */
 189             dx00             = ix0 - jx0;
 190             dy00             = iy0 - jy0;
 191             dz00             = iz0 - jz0;
 192             dx10             = ix1 - jx0;
 193             dy10             = iy1 - jy0;
 194             dz10             = iz1 - jz0;
 195             dx20             = ix2 - jx0;
 196             dy20             = iy2 - jy0;
 197             dz20             = iz2 - jz0;
 198             dx30             = ix3 - jx0;
 199             dy30             = iy3 - jy0;
 200             dz30             = iz3 - jz0;
 201
 202             /* Calculate squared distance and things based on it */
 203             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 204             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 205             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 206             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 207
 208             rinv00           = gmx_invsqrt(rsq00);
 209             rinv10           = gmx_invsqrt(rsq10);
 210             rinv20           = gmx_invsqrt(rsq20);
 211             rinv30           = gmx_invsqrt(rsq30);
 212
 213             rinvsq00         = rinv00*rinv00;
 214             rinvsq10         = rinv10*rinv10;
 215             rinvsq20         = rinv20*rinv20;
 216             rinvsq30         = rinv30*rinv30;
 217
 218             /* Load parameters for j particles */
 219             jq0              = charge[jnr+0];
 220             vdwjidx0         = 3*vdwtype[jnr+0];
 221
 222             /**************************
 223              * CALCULATE INTERACTIONS *
 224              **************************/
 225
 226             if (rsq00<rcutoff2)
 227             {
 228
 229             r00              = rsq00*rinv00;
 230
 231             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 232             cexp1_00         = vdwparam[vdwioffset0+vdwjidx0+1];
 233             cexp2_00         = vdwparam[vdwioffset0+vdwjidx0+2];
 234
 235             /* BUCKINGHAM DISPERSION/REPULSION */
 236             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 237             vvdw6            = c6_00*rinvsix;
 238             br               = cexp2_00*r00;
 239             vvdwexp          = cexp1_00*exp(-br);
 240             vvdw             = (vvdwexp-cexp1_00*exp(-cexp2_00*rvdw)) - (vvdw6 - c6_00*sh_vdw_invrcut6)*(1.0/6.0);
 241             fvdw             = (br*vvdwexp-vvdw6)*rinvsq00;
 242
 243             /* Update potential sums from outer loop */
 244             vvdwsum         += vvdw;
 245
 246             fscal            = fvdw;
 247
 248             /* Calculate temporary vectorial force */
 249             tx               = fscal*dx00;
 250             ty               = fscal*dy00;
 251             tz               = fscal*dz00;
 252
 253             /* Update vectorial force */
 254             fix0            += tx;
 255             fiy0            += ty;
 256             fiz0            += tz;
 257             f[j_coord_offset+DIM*0+XX] -= tx;
 258             f[j_coord_offset+DIM*0+YY] -= ty;
 259             f[j_coord_offset+DIM*0+ZZ] -= tz;
 260
 261             }
 262
 263             /**************************
 264              * CALCULATE INTERACTIONS *
 265              **************************/
 266
 267             if (rsq10<rcutoff2)
 268             {
 269
 270             qq10             = iq1*jq0;
 271
 272             /* REACTION-FIELD ELECTROSTATICS */
 273             velec            = qq10*(rinv10+krf*rsq10-crf);
 274             felec            = qq10*(rinv10*rinvsq10-krf2);
 275
 276             /* Update potential sums from outer loop */
 277             velecsum        += velec;
 278
 279             fscal            = felec;
 280
 281             /* Calculate temporary vectorial force */
 282             tx               = fscal*dx10;
 283             ty               = fscal*dy10;
 284             tz               = fscal*dz10;
 285
 286             /* Update vectorial force */
 287             fix1            += tx;
 288             fiy1            += ty;
 289             fiz1            += 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             }
 295
 296             /**************************
 297              * CALCULATE INTERACTIONS *
 298              **************************/
 299
 300             if (rsq20<rcutoff2)
 301             {
 302
 303             qq20             = iq2*jq0;
 304
 305             /* REACTION-FIELD ELECTROSTATICS */
 306             velec            = qq20*(rinv20+krf*rsq20-crf);
 307             felec            = qq20*(rinv20*rinvsq20-krf2);
 308
 309             /* Update potential sums from outer loop */
 310             velecsum        += velec;
 311
 312             fscal            = felec;
 313
 314             /* Calculate temporary vectorial force */
 315             tx               = fscal*dx20;
 316             ty               = fscal*dy20;
 317             tz               = fscal*dz20;
 318
 319             /* Update vectorial force */
 320             fix2            += tx;
 321             fiy2            += ty;
 322             fiz2            += tz;
 323             f[j_coord_offset+DIM*0+XX] -= tx;
 324             f[j_coord_offset+DIM*0+YY] -= ty;
 325             f[j_coord_offset+DIM*0+ZZ] -= tz;
 326
 327             }
 328
 329             /**************************
 330              * CALCULATE INTERACTIONS *
 331              **************************/
 332
 333             if (rsq30<rcutoff2)
 334             {
 335
 336             qq30             = iq3*jq0;
 337
 338             /* REACTION-FIELD ELECTROSTATICS */
 339             velec            = qq30*(rinv30+krf*rsq30-crf);
 340             felec            = qq30*(rinv30*rinvsq30-krf2);
 341
 342             /* Update potential sums from outer loop */
 343             velecsum        += velec;
 344
 345             fscal            = felec;
 346
 347             /* Calculate temporary vectorial force */
 348             tx               = fscal*dx30;
 349             ty               = fscal*dy30;
 350             tz               = fscal*dz30;
 351
 352             /* Update vectorial force */
 353             fix3            += tx;
 354             fiy3            += ty;
 355             fiz3            += tz;
 356             f[j_coord_offset+DIM*0+XX] -= tx;
 357             f[j_coord_offset+DIM*0+YY] -= ty;
 358             f[j_coord_offset+DIM*0+ZZ] -= tz;
 359
 360             }
 361
 362             /* Inner loop uses 188 flops */
 363         }
 364         /* End of innermost loop */
 365
 366         tx = ty = tz = 0;
 367         f[i_coord_offset+DIM*0+XX] += fix0;
 368         f[i_coord_offset+DIM*0+YY] += fiy0;
 369         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 370         tx                         += fix0;
 371         ty                         += fiy0;
 372         tz                         += fiz0;
 373         f[i_coord_offset+DIM*1+XX] += fix1;
 374         f[i_coord_offset+DIM*1+YY] += fiy1;
 375         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 376         tx                         += fix1;
 377         ty                         += fiy1;
 378         tz                         += fiz1;
 379         f[i_coord_offset+DIM*2+XX] += fix2;
 380         f[i_coord_offset+DIM*2+YY] += fiy2;
 381         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 382         tx                         += fix2;
 383         ty                         += fiy2;
 384         tz                         += fiz2;
 385         f[i_coord_offset+DIM*3+XX] += fix3;
 386         f[i_coord_offset+DIM*3+YY] += fiy3;
 387         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 388         tx                         += fix3;
 389         ty                         += fiy3;
 390         tz                         += fiz3;
 391         fshift[i_shift_offset+XX]  += tx;
 392         fshift[i_shift_offset+YY]  += ty;
 393         fshift[i_shift_offset+ZZ]  += tz;
 394
 395         ggid                        = gid[iidx];
 396         /* Update potential energies */
 397         kernel_data->energygrp_elec[ggid] += velecsum;
 398         kernel_data->energygrp_vdw[ggid] += vvdwsum;
 399
 400         /* Increment number of inner iterations */
 401         inneriter                  += j_index_end - j_index_start;
 402
 403         /* Outer loop uses 41 flops */
 404     }
 405
 406     /* Increment number of outer iterations */
 407     outeriter        += nri;
 408
 409     /* Update outer/inner flops */
 410
 411     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_VF,outeriter*41 + inneriter*188);
 412 }
 413 /*
 414  * Gromacs nonbonded kernel:   nb_kernel_ElecRFCut_VdwBhamSh_GeomW4P1_F_c
 415  * Electrostatics interaction: ReactionField
 416  * VdW interaction:            Buckingham
 417  * Geometry:                   Water4-Particle
 418  * Calculate force/pot:        Force
 419  */
 420 void
 421 nb_kernel_ElecRFCut_VdwBhamSh_GeomW4P1_F_c
 422                     (t_nblist                    * gmx_restrict       nlist,
 423                      rvec                        * gmx_restrict          xx,
 424                      rvec                        * gmx_restrict          ff,
 425                      t_forcerec                  * gmx_restrict          fr,
 426                      t_mdatoms                   * gmx_restrict     mdatoms,
 427                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 428                      t_nrnb                      * gmx_restrict        nrnb)
 429 {
 430     int              i_shift_offset,i_coord_offset,j_coord_offset;
 431     int              j_index_start,j_index_end;
 432     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 433     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 434     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 435     real             *shiftvec,*fshift,*x,*f;
 436     int              vdwioffset0;
 437     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 438     int              vdwioffset1;
 439     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 440     int              vdwioffset2;
 441     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 442     int              vdwioffset3;
 443     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
 444     int              vdwjidx0;
 445     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 446     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
 447     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
 448     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
 449     real             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
 450     real             velec,felec,velecsum,facel,crf,krf,krf2;
 451     real             *charge;
 452     int              nvdwtype;
 453     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
 454     int              *vdwtype;
 455     real             *vdwparam;
 456
 457     x                = xx[0];
 458     f                = ff[0];
 459
 460     nri              = nlist->nri;
 461     iinr             = nlist->iinr;
 462     jindex           = nlist->jindex;
 463     jjnr             = nlist->jjnr;
 464     shiftidx         = nlist->shift;
 465     gid              = nlist->gid;
 466     shiftvec         = fr->shift_vec[0];
 467     fshift           = fr->fshift[0];
 468     facel            = fr->epsfac;
 469     charge           = mdatoms->chargeA;
 470     krf              = fr->ic->k_rf;
 471     krf2             = krf*2.0;
 472     crf              = fr->ic->c_rf;
 473     nvdwtype         = fr->ntype;
 474     vdwparam         = fr->nbfp;
 475     vdwtype          = mdatoms->typeA;
 476
 477     /* Setup water-specific parameters */
 478     inr              = nlist->iinr[0];
 479     iq1              = facel*charge[inr+1];
 480     iq2              = facel*charge[inr+2];
 481     iq3              = facel*charge[inr+3];
 482     vdwioffset0      = 3*nvdwtype*vdwtype[inr+0];
 483
 484     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 485     rcutoff          = fr->rcoulomb;
 486     rcutoff2         = rcutoff*rcutoff;
 487
 488     sh_vdw_invrcut6  = fr->ic->sh_invrc6;
 489     rvdw             = fr->rvdw;
 490
 491     outeriter        = 0;
 492     inneriter        = 0;
 493
 494     /* Start outer loop over neighborlists */
 495     for(iidx=0; iidx<nri; iidx++)
 496     {
 497         /* Load shift vector for this list */
 498         i_shift_offset   = DIM*shiftidx[iidx];
 499         shX              = shiftvec[i_shift_offset+XX];
 500         shY              = shiftvec[i_shift_offset+YY];
 501         shZ              = shiftvec[i_shift_offset+ZZ];
 502
 503         /* Load limits for loop over neighbors */
 504         j_index_start    = jindex[iidx];
 505         j_index_end      = jindex[iidx+1];
 506
 507         /* Get outer coordinate index */
 508         inr              = iinr[iidx];
 509         i_coord_offset   = DIM*inr;
 510
 511         /* Load i particle coords and add shift vector */
 512         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 513         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 514         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 515         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 516         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 517         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 518         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 519         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 520         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 521         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 522         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 523         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 524
 525         fix0             = 0.0;
 526         fiy0             = 0.0;
 527         fiz0             = 0.0;
 528         fix1             = 0.0;
 529         fiy1             = 0.0;
 530         fiz1             = 0.0;
 531         fix2             = 0.0;
 532         fiy2             = 0.0;
 533         fiz2             = 0.0;
 534         fix3             = 0.0;
 535         fiy3             = 0.0;
 536         fiz3             = 0.0;
 537
 538         /* Start inner kernel loop */
 539         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 540         {
 541             /* Get j neighbor index, and coordinate index */
 542             jnr              = jjnr[jidx];
 543             j_coord_offset   = DIM*jnr;
 544
 545             /* load j atom coordinates */
 546             jx0              = x[j_coord_offset+DIM*0+XX];
 547             jy0              = x[j_coord_offset+DIM*0+YY];
 548             jz0              = x[j_coord_offset+DIM*0+ZZ];
 549
 550             /* Calculate displacement vector */
 551             dx00             = ix0 - jx0;
 552             dy00             = iy0 - jy0;
 553             dz00             = iz0 - jz0;
 554             dx10             = ix1 - jx0;
 555             dy10             = iy1 - jy0;
 556             dz10             = iz1 - jz0;
 557             dx20             = ix2 - jx0;
 558             dy20             = iy2 - jy0;
 559             dz20             = iz2 - jz0;
 560             dx30             = ix3 - jx0;
 561             dy30             = iy3 - jy0;
 562             dz30             = iz3 - jz0;
 563
 564             /* Calculate squared distance and things based on it */
 565             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 566             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 567             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 568             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 569
 570             rinv00           = gmx_invsqrt(rsq00);
 571             rinv10           = gmx_invsqrt(rsq10);
 572             rinv20           = gmx_invsqrt(rsq20);
 573             rinv30           = gmx_invsqrt(rsq30);
 574
 575             rinvsq00         = rinv00*rinv00;
 576             rinvsq10         = rinv10*rinv10;
 577             rinvsq20         = rinv20*rinv20;
 578             rinvsq30         = rinv30*rinv30;
 579
 580             /* Load parameters for j particles */
 581             jq0              = charge[jnr+0];
 582             vdwjidx0         = 3*vdwtype[jnr+0];
 583
 584             /**************************
 585              * CALCULATE INTERACTIONS *
 586              **************************/
 587
 588             if (rsq00<rcutoff2)
 589             {
 590
 591             r00              = rsq00*rinv00;
 592
 593             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 594             cexp1_00         = vdwparam[vdwioffset0+vdwjidx0+1];
 595             cexp2_00         = vdwparam[vdwioffset0+vdwjidx0+2];
 596
 597             /* BUCKINGHAM DISPERSION/REPULSION */
 598             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 599             vvdw6            = c6_00*rinvsix;
 600             br               = cexp2_00*r00;
 601             vvdwexp          = cexp1_00*exp(-br);
 602             fvdw             = (br*vvdwexp-vvdw6)*rinvsq00;
 603
 604             fscal            = fvdw;
 605
 606             /* Calculate temporary vectorial force */
 607             tx               = fscal*dx00;
 608             ty               = fscal*dy00;
 609             tz               = fscal*dz00;
 610
 611             /* Update vectorial force */
 612             fix0            += tx;
 613             fiy0            += ty;
 614             fiz0            += tz;
 615             f[j_coord_offset+DIM*0+XX] -= tx;
 616             f[j_coord_offset+DIM*0+YY] -= ty;
 617             f[j_coord_offset+DIM*0+ZZ] -= tz;
 618
 619             }
 620
 621             /**************************
 622              * CALCULATE INTERACTIONS *
 623              **************************/
 624
 625             if (rsq10<rcutoff2)
 626             {
 627
 628             qq10             = iq1*jq0;
 629
 630             /* REACTION-FIELD ELECTROSTATICS */
 631             felec            = qq10*(rinv10*rinvsq10-krf2);
 632
 633             fscal            = felec;
 634
 635             /* Calculate temporary vectorial force */
 636             tx               = fscal*dx10;
 637             ty               = fscal*dy10;
 638             tz               = fscal*dz10;
 639
 640             /* Update vectorial force */
 641             fix1            += tx;
 642             fiy1            += ty;
 643             fiz1            += tz;
 644             f[j_coord_offset+DIM*0+XX] -= tx;
 645             f[j_coord_offset+DIM*0+YY] -= ty;
 646             f[j_coord_offset+DIM*0+ZZ] -= tz;
 647
 648             }
 649
 650             /**************************
 651              * CALCULATE INTERACTIONS *
 652              **************************/
 653
 654             if (rsq20<rcutoff2)
 655             {
 656
 657             qq20             = iq2*jq0;
 658
 659             /* REACTION-FIELD ELECTROSTATICS */
 660             felec            = qq20*(rinv20*rinvsq20-krf2);
 661
 662             fscal            = felec;
 663
 664             /* Calculate temporary vectorial force */
 665             tx               = fscal*dx20;
 666             ty               = fscal*dy20;
 667             tz               = fscal*dz20;
 668
 669             /* Update vectorial force */
 670             fix2            += tx;
 671             fiy2            += ty;
 672             fiz2            += tz;
 673             f[j_coord_offset+DIM*0+XX] -= tx;
 674             f[j_coord_offset+DIM*0+YY] -= ty;
 675             f[j_coord_offset+DIM*0+ZZ] -= tz;
 676
 677             }
 678
 679             /**************************
 680              * CALCULATE INTERACTIONS *
 681              **************************/
 682
 683             if (rsq30<rcutoff2)
 684             {
 685
 686             qq30             = iq3*jq0;
 687
 688             /* REACTION-FIELD ELECTROSTATICS */
 689             felec            = qq30*(rinv30*rinvsq30-krf2);
 690
 691             fscal            = felec;
 692
 693             /* Calculate temporary vectorial force */
 694             tx               = fscal*dx30;
 695             ty               = fscal*dy30;
 696             tz               = fscal*dz30;
 697
 698             /* Update vectorial force */
 699             fix3            += tx;
 700             fiy3            += ty;
 701             fiz3            += tz;
 702             f[j_coord_offset+DIM*0+XX] -= tx;
 703             f[j_coord_offset+DIM*0+YY] -= ty;
 704             f[j_coord_offset+DIM*0+ZZ] -= tz;
 705
 706             }
 707
 708             /* Inner loop uses 139 flops */
 709         }
 710         /* End of innermost loop */
 711
 712         tx = ty = tz = 0;
 713         f[i_coord_offset+DIM*0+XX] += fix0;
 714         f[i_coord_offset+DIM*0+YY] += fiy0;
 715         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 716         tx                         += fix0;
 717         ty                         += fiy0;
 718         tz                         += fiz0;
 719         f[i_coord_offset+DIM*1+XX] += fix1;
 720         f[i_coord_offset+DIM*1+YY] += fiy1;
 721         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 722         tx                         += fix1;
 723         ty                         += fiy1;
 724         tz                         += fiz1;
 725         f[i_coord_offset+DIM*2+XX] += fix2;
 726         f[i_coord_offset+DIM*2+YY] += fiy2;
 727         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 728         tx                         += fix2;
 729         ty                         += fiy2;
 730         tz                         += fiz2;
 731         f[i_coord_offset+DIM*3+XX] += fix3;
 732         f[i_coord_offset+DIM*3+YY] += fiy3;
 733         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 734         tx                         += fix3;
 735         ty                         += fiy3;
 736         tz                         += fiz3;
 737         fshift[i_shift_offset+XX]  += tx;
 738         fshift[i_shift_offset+YY]  += ty;
 739         fshift[i_shift_offset+ZZ]  += tz;
 740
 741         /* Increment number of inner iterations */
 742         inneriter                  += j_index_end - j_index_start;
 743
 744         /* Outer loop uses 39 flops */
 745     }
 746
 747     /* Increment number of outer iterations */
 748     outeriter        += nri;
 749
 750     /* Update outer/inner flops */
 751
 752     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_F,outeriter*39 + inneriter*139);
 753 }