src/gromacs/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecRFCut_VdwLJSh_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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  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_ElecRFCut_VdwLJSh_GeomW4P1_VF_c
  51  * Electrostatics interaction: ReactionField
  52  * VdW interaction:            LennardJones
  53  * Geometry:                   Water4-Particle
  54  * Calculate force/pot:        PotentialAndForce
  55  */
  56 void
  57 nb_kernel_ElecRFCut_VdwLJSh_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              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              vdwioffset3;
  79     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
  80     int              vdwjidx0;
  81     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  82     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
  83     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
  84     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
  85     real             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
  86     real             velec,felec,velecsum,facel,crf,krf,krf2;
  87     real             *charge;
  88     int              nvdwtype;
  89     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
  90     int              *vdwtype;
  91     real             *vdwparam;
  92
  93     x                = xx[0];
  94     f                = ff[0];
  95
  96     nri              = nlist->nri;
  97     iinr             = nlist->iinr;
  98     jindex           = nlist->jindex;
  99     jjnr             = nlist->jjnr;
 100     shiftidx         = nlist->shift;
 101     gid              = nlist->gid;
 102     shiftvec         = fr->shift_vec[0];
 103     fshift           = fr->fshift[0];
 104     facel            = fr->epsfac;
 105     charge           = mdatoms->chargeA;
 106     krf              = fr->ic->k_rf;
 107     krf2             = krf*2.0;
 108     crf              = fr->ic->c_rf;
 109     nvdwtype         = fr->ntype;
 110     vdwparam         = fr->nbfp;
 111     vdwtype          = mdatoms->typeA;
 112
 113     /* Setup water-specific parameters */
 114     inr              = nlist->iinr[0];
 115     iq1              = facel*charge[inr+1];
 116     iq2              = facel*charge[inr+2];
 117     iq3              = facel*charge[inr+3];
 118     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 119
 120     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 121     rcutoff          = fr->rcoulomb;
 122     rcutoff2         = rcutoff*rcutoff;
 123
 124     sh_vdw_invrcut6  = fr->ic->sh_invrc6;
 125     rvdw             = fr->rvdw;
 126
 127     outeriter        = 0;
 128     inneriter        = 0;
 129
 130     /* Start outer loop over neighborlists */
 131     for(iidx=0; iidx<nri; iidx++)
 132     {
 133         /* Load shift vector for this list */
 134         i_shift_offset   = DIM*shiftidx[iidx];
 135         shX              = shiftvec[i_shift_offset+XX];
 136         shY              = shiftvec[i_shift_offset+YY];
 137         shZ              = shiftvec[i_shift_offset+ZZ];
 138
 139         /* Load limits for loop over neighbors */
 140         j_index_start    = jindex[iidx];
 141         j_index_end      = jindex[iidx+1];
 142
 143         /* Get outer coordinate index */
 144         inr              = iinr[iidx];
 145         i_coord_offset   = DIM*inr;
 146
 147         /* Load i particle coords and add shift vector */
 148         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 149         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 150         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 151         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 152         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 153         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 154         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 155         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 156         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 157         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 158         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 159         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 160
 161         fix0             = 0.0;
 162         fiy0             = 0.0;
 163         fiz0             = 0.0;
 164         fix1             = 0.0;
 165         fiy1             = 0.0;
 166         fiz1             = 0.0;
 167         fix2             = 0.0;
 168         fiy2             = 0.0;
 169         fiz2             = 0.0;
 170         fix3             = 0.0;
 171         fiy3             = 0.0;
 172         fiz3             = 0.0;
 173
 174         /* Reset potential sums */
 175         velecsum         = 0.0;
 176         vvdwsum          = 0.0;
 177
 178         /* Start inner kernel loop */
 179         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 180         {
 181             /* Get j neighbor index, and coordinate index */
 182             jnr              = jjnr[jidx];
 183             j_coord_offset   = DIM*jnr;
 184
 185             /* load j atom coordinates */
 186             jx0              = x[j_coord_offset+DIM*0+XX];
 187             jy0              = x[j_coord_offset+DIM*0+YY];
 188             jz0              = x[j_coord_offset+DIM*0+ZZ];
 189
 190             /* Calculate displacement vector */
 191             dx00             = ix0 - jx0;
 192             dy00             = iy0 - jy0;
 193             dz00             = iz0 - jz0;
 194             dx10             = ix1 - jx0;
 195             dy10             = iy1 - jy0;
 196             dz10             = iz1 - jz0;
 197             dx20             = ix2 - jx0;
 198             dy20             = iy2 - jy0;
 199             dz20             = iz2 - jz0;
 200             dx30             = ix3 - jx0;
 201             dy30             = iy3 - jy0;
 202             dz30             = iz3 - jz0;
 203
 204             /* Calculate squared distance and things based on it */
 205             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 206             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 207             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 208             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 209
 210             rinv10           = gmx_invsqrt(rsq10);
 211             rinv20           = gmx_invsqrt(rsq20);
 212             rinv30           = gmx_invsqrt(rsq30);
 213
 214             rinvsq00         = 1.0/rsq00;
 215             rinvsq10         = rinv10*rinv10;
 216             rinvsq20         = rinv20*rinv20;
 217             rinvsq30         = rinv30*rinv30;
 218
 219             /* Load parameters for j particles */
 220             jq0              = charge[jnr+0];
 221             vdwjidx0         = 2*vdwtype[jnr+0];
 222
 223             /**************************
 224              * CALCULATE INTERACTIONS *
 225              **************************/
 226
 227             if (rsq00<rcutoff2)
 228             {
 229
 230             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 231             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 232
 233             /* LENNARD-JONES DISPERSION/REPULSION */
 234
 235             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 236             vvdw6            = c6_00*rinvsix;
 237             vvdw12           = c12_00*rinvsix*rinvsix;
 238             vvdw             = (vvdw12 - c12_00*sh_vdw_invrcut6*sh_vdw_invrcut6)*(1.0/12.0) - (vvdw6 - c6_00*sh_vdw_invrcut6)*(1.0/6.0);
 239             fvdw             = (vvdw12-vvdw6)*rinvsq00;
 240
 241             /* Update potential sums from outer loop */
 242             vvdwsum         += vvdw;
 243
 244             fscal            = fvdw;
 245
 246             /* Calculate temporary vectorial force */
 247             tx               = fscal*dx00;
 248             ty               = fscal*dy00;
 249             tz               = fscal*dz00;
 250
 251             /* Update vectorial force */
 252             fix0            += tx;
 253             fiy0            += ty;
 254             fiz0            += tz;
 255             f[j_coord_offset+DIM*0+XX] -= tx;
 256             f[j_coord_offset+DIM*0+YY] -= ty;
 257             f[j_coord_offset+DIM*0+ZZ] -= tz;
 258
 259             }
 260
 261             /**************************
 262              * CALCULATE INTERACTIONS *
 263              **************************/
 264
 265             if (rsq10<rcutoff2)
 266             {
 267
 268             qq10             = iq1*jq0;
 269
 270             /* REACTION-FIELD ELECTROSTATICS */
 271             velec            = qq10*(rinv10+krf*rsq10-crf);
 272             felec            = qq10*(rinv10*rinvsq10-krf2);
 273
 274             /* Update potential sums from outer loop */
 275             velecsum        += velec;
 276
 277             fscal            = felec;
 278
 279             /* Calculate temporary vectorial force */
 280             tx               = fscal*dx10;
 281             ty               = fscal*dy10;
 282             tz               = fscal*dz10;
 283
 284             /* Update vectorial force */
 285             fix1            += tx;
 286             fiy1            += ty;
 287             fiz1            += tz;
 288             f[j_coord_offset+DIM*0+XX] -= tx;
 289             f[j_coord_offset+DIM*0+YY] -= ty;
 290             f[j_coord_offset+DIM*0+ZZ] -= tz;
 291
 292             }
 293
 294             /**************************
 295              * CALCULATE INTERACTIONS *
 296              **************************/
 297
 298             if (rsq20<rcutoff2)
 299             {
 300
 301             qq20             = iq2*jq0;
 302
 303             /* REACTION-FIELD ELECTROSTATICS */
 304             velec            = qq20*(rinv20+krf*rsq20-crf);
 305             felec            = qq20*(rinv20*rinvsq20-krf2);
 306
 307             /* Update potential sums from outer loop */
 308             velecsum        += velec;
 309
 310             fscal            = felec;
 311
 312             /* Calculate temporary vectorial force */
 313             tx               = fscal*dx20;
 314             ty               = fscal*dy20;
 315             tz               = fscal*dz20;
 316
 317             /* Update vectorial force */
 318             fix2            += tx;
 319             fiy2            += ty;
 320             fiz2            += tz;
 321             f[j_coord_offset+DIM*0+XX] -= tx;
 322             f[j_coord_offset+DIM*0+YY] -= ty;
 323             f[j_coord_offset+DIM*0+ZZ] -= tz;
 324
 325             }
 326
 327             /**************************
 328              * CALCULATE INTERACTIONS *
 329              **************************/
 330
 331             if (rsq30<rcutoff2)
 332             {
 333
 334             qq30             = iq3*jq0;
 335
 336             /* REACTION-FIELD ELECTROSTATICS */
 337             velec            = qq30*(rinv30+krf*rsq30-crf);
 338             felec            = qq30*(rinv30*rinvsq30-krf2);
 339
 340             /* Update potential sums from outer loop */
 341             velecsum        += velec;
 342
 343             fscal            = felec;
 344
 345             /* Calculate temporary vectorial force */
 346             tx               = fscal*dx30;
 347             ty               = fscal*dy30;
 348             tz               = fscal*dz30;
 349
 350             /* Update vectorial force */
 351             fix3            += tx;
 352             fiy3            += ty;
 353             fiz3            += tz;
 354             f[j_coord_offset+DIM*0+XX] -= tx;
 355             f[j_coord_offset+DIM*0+YY] -= ty;
 356             f[j_coord_offset+DIM*0+ZZ] -= tz;
 357
 358             }
 359
 360             /* Inner loop uses 133 flops */
 361         }
 362         /* End of innermost loop */
 363
 364         tx = ty = tz = 0;
 365         f[i_coord_offset+DIM*0+XX] += fix0;
 366         f[i_coord_offset+DIM*0+YY] += fiy0;
 367         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 368         tx                         += fix0;
 369         ty                         += fiy0;
 370         tz                         += fiz0;
 371         f[i_coord_offset+DIM*1+XX] += fix1;
 372         f[i_coord_offset+DIM*1+YY] += fiy1;
 373         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 374         tx                         += fix1;
 375         ty                         += fiy1;
 376         tz                         += fiz1;
 377         f[i_coord_offset+DIM*2+XX] += fix2;
 378         f[i_coord_offset+DIM*2+YY] += fiy2;
 379         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 380         tx                         += fix2;
 381         ty                         += fiy2;
 382         tz                         += fiz2;
 383         f[i_coord_offset+DIM*3+XX] += fix3;
 384         f[i_coord_offset+DIM*3+YY] += fiy3;
 385         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 386         tx                         += fix3;
 387         ty                         += fiy3;
 388         tz                         += fiz3;
 389         fshift[i_shift_offset+XX]  += tx;
 390         fshift[i_shift_offset+YY]  += ty;
 391         fshift[i_shift_offset+ZZ]  += tz;
 392
 393         ggid                        = gid[iidx];
 394         /* Update potential energies */
 395         kernel_data->energygrp_elec[ggid] += velecsum;
 396         kernel_data->energygrp_vdw[ggid] += vvdwsum;
 397
 398         /* Increment number of inner iterations */
 399         inneriter                  += j_index_end - j_index_start;
 400
 401         /* Outer loop uses 41 flops */
 402     }
 403
 404     /* Increment number of outer iterations */
 405     outeriter        += nri;
 406
 407     /* Update outer/inner flops */
 408
 409     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_VF,outeriter*41 + inneriter*133);
 410 }
 411 /*
 412  * Gromacs nonbonded kernel:   nb_kernel_ElecRFCut_VdwLJSh_GeomW4P1_F_c
 413  * Electrostatics interaction: ReactionField
 414  * VdW interaction:            LennardJones
 415  * Geometry:                   Water4-Particle
 416  * Calculate force/pot:        Force
 417  */
 418 void
 419 nb_kernel_ElecRFCut_VdwLJSh_GeomW4P1_F_c
 420                     (t_nblist                    * gmx_restrict       nlist,
 421                      rvec                        * gmx_restrict          xx,
 422                      rvec                        * gmx_restrict          ff,
 423                      t_forcerec                  * gmx_restrict          fr,
 424                      t_mdatoms                   * gmx_restrict     mdatoms,
 425                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 426                      t_nrnb                      * gmx_restrict        nrnb)
 427 {
 428     int              i_shift_offset,i_coord_offset,j_coord_offset;
 429     int              j_index_start,j_index_end;
 430     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 431     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 432     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 433     real             *shiftvec,*fshift,*x,*f;
 434     int              vdwioffset0;
 435     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 436     int              vdwioffset1;
 437     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 438     int              vdwioffset2;
 439     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 440     int              vdwioffset3;
 441     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
 442     int              vdwjidx0;
 443     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 444     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
 445     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
 446     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
 447     real             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
 448     real             velec,felec,velecsum,facel,crf,krf,krf2;
 449     real             *charge;
 450     int              nvdwtype;
 451     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
 452     int              *vdwtype;
 453     real             *vdwparam;
 454
 455     x                = xx[0];
 456     f                = ff[0];
 457
 458     nri              = nlist->nri;
 459     iinr             = nlist->iinr;
 460     jindex           = nlist->jindex;
 461     jjnr             = nlist->jjnr;
 462     shiftidx         = nlist->shift;
 463     gid              = nlist->gid;
 464     shiftvec         = fr->shift_vec[0];
 465     fshift           = fr->fshift[0];
 466     facel            = fr->epsfac;
 467     charge           = mdatoms->chargeA;
 468     krf              = fr->ic->k_rf;
 469     krf2             = krf*2.0;
 470     crf              = fr->ic->c_rf;
 471     nvdwtype         = fr->ntype;
 472     vdwparam         = fr->nbfp;
 473     vdwtype          = mdatoms->typeA;
 474
 475     /* Setup water-specific parameters */
 476     inr              = nlist->iinr[0];
 477     iq1              = facel*charge[inr+1];
 478     iq2              = facel*charge[inr+2];
 479     iq3              = facel*charge[inr+3];
 480     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 481
 482     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 483     rcutoff          = fr->rcoulomb;
 484     rcutoff2         = rcutoff*rcutoff;
 485
 486     sh_vdw_invrcut6  = fr->ic->sh_invrc6;
 487     rvdw             = fr->rvdw;
 488
 489     outeriter        = 0;
 490     inneriter        = 0;
 491
 492     /* Start outer loop over neighborlists */
 493     for(iidx=0; iidx<nri; iidx++)
 494     {
 495         /* Load shift vector for this list */
 496         i_shift_offset   = DIM*shiftidx[iidx];
 497         shX              = shiftvec[i_shift_offset+XX];
 498         shY              = shiftvec[i_shift_offset+YY];
 499         shZ              = shiftvec[i_shift_offset+ZZ];
 500
 501         /* Load limits for loop over neighbors */
 502         j_index_start    = jindex[iidx];
 503         j_index_end      = jindex[iidx+1];
 504
 505         /* Get outer coordinate index */
 506         inr              = iinr[iidx];
 507         i_coord_offset   = DIM*inr;
 508
 509         /* Load i particle coords and add shift vector */
 510         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 511         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 512         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 513         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 514         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 515         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 516         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 517         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 518         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 519         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 520         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 521         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 522
 523         fix0             = 0.0;
 524         fiy0             = 0.0;
 525         fiz0             = 0.0;
 526         fix1             = 0.0;
 527         fiy1             = 0.0;
 528         fiz1             = 0.0;
 529         fix2             = 0.0;
 530         fiy2             = 0.0;
 531         fiz2             = 0.0;
 532         fix3             = 0.0;
 533         fiy3             = 0.0;
 534         fiz3             = 0.0;
 535
 536         /* Start inner kernel loop */
 537         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 538         {
 539             /* Get j neighbor index, and coordinate index */
 540             jnr              = jjnr[jidx];
 541             j_coord_offset   = DIM*jnr;
 542
 543             /* load j atom coordinates */
 544             jx0              = x[j_coord_offset+DIM*0+XX];
 545             jy0              = x[j_coord_offset+DIM*0+YY];
 546             jz0              = x[j_coord_offset+DIM*0+ZZ];
 547
 548             /* Calculate displacement vector */
 549             dx00             = ix0 - jx0;
 550             dy00             = iy0 - jy0;
 551             dz00             = iz0 - jz0;
 552             dx10             = ix1 - jx0;
 553             dy10             = iy1 - jy0;
 554             dz10             = iz1 - jz0;
 555             dx20             = ix2 - jx0;
 556             dy20             = iy2 - jy0;
 557             dz20             = iz2 - jz0;
 558             dx30             = ix3 - jx0;
 559             dy30             = iy3 - jy0;
 560             dz30             = iz3 - jz0;
 561
 562             /* Calculate squared distance and things based on it */
 563             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 564             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 565             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 566             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 567
 568             rinv10           = gmx_invsqrt(rsq10);
 569             rinv20           = gmx_invsqrt(rsq20);
 570             rinv30           = gmx_invsqrt(rsq30);
 571
 572             rinvsq00         = 1.0/rsq00;
 573             rinvsq10         = rinv10*rinv10;
 574             rinvsq20         = rinv20*rinv20;
 575             rinvsq30         = rinv30*rinv30;
 576
 577             /* Load parameters for j particles */
 578             jq0              = charge[jnr+0];
 579             vdwjidx0         = 2*vdwtype[jnr+0];
 580
 581             /**************************
 582              * CALCULATE INTERACTIONS *
 583              **************************/
 584
 585             if (rsq00<rcutoff2)
 586             {
 587
 588             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 589             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 590
 591             /* LENNARD-JONES DISPERSION/REPULSION */
 592
 593             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 594             fvdw             = (c12_00*rinvsix-c6_00)*rinvsix*rinvsq00;
 595
 596             fscal            = fvdw;
 597
 598             /* Calculate temporary vectorial force */
 599             tx               = fscal*dx00;
 600             ty               = fscal*dy00;
 601             tz               = fscal*dz00;
 602
 603             /* Update vectorial force */
 604             fix0            += tx;
 605             fiy0            += ty;
 606             fiz0            += tz;
 607             f[j_coord_offset+DIM*0+XX] -= tx;
 608             f[j_coord_offset+DIM*0+YY] -= ty;
 609             f[j_coord_offset+DIM*0+ZZ] -= tz;
 610
 611             }
 612
 613             /**************************
 614              * CALCULATE INTERACTIONS *
 615              **************************/
 616
 617             if (rsq10<rcutoff2)
 618             {
 619
 620             qq10             = iq1*jq0;
 621
 622             /* REACTION-FIELD ELECTROSTATICS */
 623             felec            = qq10*(rinv10*rinvsq10-krf2);
 624
 625             fscal            = felec;
 626
 627             /* Calculate temporary vectorial force */
 628             tx               = fscal*dx10;
 629             ty               = fscal*dy10;
 630             tz               = fscal*dz10;
 631
 632             /* Update vectorial force */
 633             fix1            += tx;
 634             fiy1            += ty;
 635             fiz1            += tz;
 636             f[j_coord_offset+DIM*0+XX] -= tx;
 637             f[j_coord_offset+DIM*0+YY] -= ty;
 638             f[j_coord_offset+DIM*0+ZZ] -= tz;
 639
 640             }
 641
 642             /**************************
 643              * CALCULATE INTERACTIONS *
 644              **************************/
 645
 646             if (rsq20<rcutoff2)
 647             {
 648
 649             qq20             = iq2*jq0;
 650
 651             /* REACTION-FIELD ELECTROSTATICS */
 652             felec            = qq20*(rinv20*rinvsq20-krf2);
 653
 654             fscal            = felec;
 655
 656             /* Calculate temporary vectorial force */
 657             tx               = fscal*dx20;
 658             ty               = fscal*dy20;
 659             tz               = fscal*dz20;
 660
 661             /* Update vectorial force */
 662             fix2            += tx;
 663             fiy2            += ty;
 664             fiz2            += tz;
 665             f[j_coord_offset+DIM*0+XX] -= tx;
 666             f[j_coord_offset+DIM*0+YY] -= ty;
 667             f[j_coord_offset+DIM*0+ZZ] -= tz;
 668
 669             }
 670
 671             /**************************
 672              * CALCULATE INTERACTIONS *
 673              **************************/
 674
 675             if (rsq30<rcutoff2)
 676             {
 677
 678             qq30             = iq3*jq0;
 679
 680             /* REACTION-FIELD ELECTROSTATICS */
 681             felec            = qq30*(rinv30*rinvsq30-krf2);
 682
 683             fscal            = felec;
 684
 685             /* Calculate temporary vectorial force */
 686             tx               = fscal*dx30;
 687             ty               = fscal*dy30;
 688             tz               = fscal*dz30;
 689
 690             /* Update vectorial force */
 691             fix3            += tx;
 692             fiy3            += ty;
 693             fiz3            += tz;
 694             f[j_coord_offset+DIM*0+XX] -= tx;
 695             f[j_coord_offset+DIM*0+YY] -= ty;
 696             f[j_coord_offset+DIM*0+ZZ] -= tz;
 697
 698             }
 699
 700             /* Inner loop uses 108 flops */
 701         }
 702         /* End of innermost loop */
 703
 704         tx = ty = tz = 0;
 705         f[i_coord_offset+DIM*0+XX] += fix0;
 706         f[i_coord_offset+DIM*0+YY] += fiy0;
 707         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 708         tx                         += fix0;
 709         ty                         += fiy0;
 710         tz                         += fiz0;
 711         f[i_coord_offset+DIM*1+XX] += fix1;
 712         f[i_coord_offset+DIM*1+YY] += fiy1;
 713         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 714         tx                         += fix1;
 715         ty                         += fiy1;
 716         tz                         += fiz1;
 717         f[i_coord_offset+DIM*2+XX] += fix2;
 718         f[i_coord_offset+DIM*2+YY] += fiy2;
 719         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 720         tx                         += fix2;
 721         ty                         += fiy2;
 722         tz                         += fiz2;
 723         f[i_coord_offset+DIM*3+XX] += fix3;
 724         f[i_coord_offset+DIM*3+YY] += fiy3;
 725         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 726         tx                         += fix3;
 727         ty                         += fiy3;
 728         tz                         += fiz3;
 729         fshift[i_shift_offset+XX]  += tx;
 730         fshift[i_shift_offset+YY]  += ty;
 731         fshift[i_shift_offset+ZZ]  += tz;
 732
 733         /* Increment number of inner iterations */
 734         inneriter                  += j_index_end - j_index_start;
 735
 736         /* Outer loop uses 39 flops */
 737     }
 738
 739     /* Increment number of outer iterations */
 740     outeriter        += nri;
 741
 742     /* Update outer/inner flops */
 743
 744     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_F,outeriter*39 + inneriter*108);
 745 }