src/gromacs/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecRF_VdwCSTab_GeomW4P1_c.c

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2012,2013, by the GROMACS development team, led by
   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
   6  * and including many others, as listed in the AUTHORS file in the
   7  * top-level source directory and at http://www.gromacs.org.
   8  *
   9  * GROMACS is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1
  12  * of the License, or (at your option) any later version.
  13  *
  14  * GROMACS is distributed in the hope that it will be useful,
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  17  * Lesser General Public License for more details.
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  34  */
  35 /*
  36  * Note: this file was generated by the GROMACS 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 "vec.h"
  47 #include "nrnb.h"
  48
  49 /*
  50  * Gromacs nonbonded kernel:   nb_kernel_ElecRF_VdwCSTab_GeomW4P1_VF_c
  51  * Electrostatics interaction: ReactionField
  52  * VdW interaction:            CubicSplineTable
  53  * Geometry:                   Water4-Particle
  54  * Calculate force/pot:        PotentialAndForce
  55  */
  56 void
  57 nb_kernel_ElecRF_VdwCSTab_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     int              vfitab;
  93     real             rt,vfeps,vftabscale,Y,F,Geps,Heps2,Fp,VV,FF;
  94     real             *vftab;
  95
  96     x                = xx[0];
  97     f                = ff[0];
  98
  99     nri              = nlist->nri;
 100     iinr             = nlist->iinr;
 101     jindex           = nlist->jindex;
 102     jjnr             = nlist->jjnr;
 103     shiftidx         = nlist->shift;
 104     gid              = nlist->gid;
 105     shiftvec         = fr->shift_vec[0];
 106     fshift           = fr->fshift[0];
 107     facel            = fr->epsfac;
 108     charge           = mdatoms->chargeA;
 109     krf              = fr->ic->k_rf;
 110     krf2             = krf*2.0;
 111     crf              = fr->ic->c_rf;
 112     nvdwtype         = fr->ntype;
 113     vdwparam         = fr->nbfp;
 114     vdwtype          = mdatoms->typeA;
 115
 116     vftab            = kernel_data->table_vdw->data;
 117     vftabscale       = kernel_data->table_vdw->scale;
 118
 119     /* Setup water-specific parameters */
 120     inr              = nlist->iinr[0];
 121     iq1              = facel*charge[inr+1];
 122     iq2              = facel*charge[inr+2];
 123     iq3              = facel*charge[inr+3];
 124     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 125
 126     outeriter        = 0;
 127     inneriter        = 0;
 128
 129     /* Start outer loop over neighborlists */
 130     for(iidx=0; iidx<nri; iidx++)
 131     {
 132         /* Load shift vector for this list */
 133         i_shift_offset   = DIM*shiftidx[iidx];
 134         shX              = shiftvec[i_shift_offset+XX];
 135         shY              = shiftvec[i_shift_offset+YY];
 136         shZ              = shiftvec[i_shift_offset+ZZ];
 137
 138         /* Load limits for loop over neighbors */
 139         j_index_start    = jindex[iidx];
 140         j_index_end      = jindex[iidx+1];
 141
 142         /* Get outer coordinate index */
 143         inr              = iinr[iidx];
 144         i_coord_offset   = DIM*inr;
 145
 146         /* Load i particle coords and add shift vector */
 147         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 148         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 149         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 150         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 151         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 152         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 153         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 154         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 155         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 156         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 157         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 158         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 159
 160         fix0             = 0.0;
 161         fiy0             = 0.0;
 162         fiz0             = 0.0;
 163         fix1             = 0.0;
 164         fiy1             = 0.0;
 165         fiz1             = 0.0;
 166         fix2             = 0.0;
 167         fiy2             = 0.0;
 168         fiz2             = 0.0;
 169         fix3             = 0.0;
 170         fiy3             = 0.0;
 171         fiz3             = 0.0;
 172
 173         /* Reset potential sums */
 174         velecsum         = 0.0;
 175         vvdwsum          = 0.0;
 176
 177         /* Start inner kernel loop */
 178         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 179         {
 180             /* Get j neighbor index, and coordinate index */
 181             jnr              = jjnr[jidx];
 182             j_coord_offset   = DIM*jnr;
 183
 184             /* load j atom coordinates */
 185             jx0              = x[j_coord_offset+DIM*0+XX];
 186             jy0              = x[j_coord_offset+DIM*0+YY];
 187             jz0              = x[j_coord_offset+DIM*0+ZZ];
 188
 189             /* Calculate displacement vector */
 190             dx00             = ix0 - jx0;
 191             dy00             = iy0 - jy0;
 192             dz00             = iz0 - jz0;
 193             dx10             = ix1 - jx0;
 194             dy10             = iy1 - jy0;
 195             dz10             = iz1 - jz0;
 196             dx20             = ix2 - jx0;
 197             dy20             = iy2 - jy0;
 198             dz20             = iz2 - jz0;
 199             dx30             = ix3 - jx0;
 200             dy30             = iy3 - jy0;
 201             dz30             = iz3 - jz0;
 202
 203             /* Calculate squared distance and things based on it */
 204             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 205             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 206             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 207             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 208
 209             rinv00           = gmx_invsqrt(rsq00);
 210             rinv10           = gmx_invsqrt(rsq10);
 211             rinv20           = gmx_invsqrt(rsq20);
 212             rinv30           = gmx_invsqrt(rsq30);
 213
 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         = 2*vdwtype[jnr+0];
 221
 222             /**************************
 223              * CALCULATE INTERACTIONS *
 224              **************************/
 225
 226             r00              = rsq00*rinv00;
 227
 228             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 229             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 230
 231             /* Calculate table index by multiplying r with table scale and truncate to integer */
 232             rt               = r00*vftabscale;
 233             vfitab           = rt;
 234             vfeps            = rt-vfitab;
 235             vfitab           = 2*4*vfitab;
 236
 237             /* CUBIC SPLINE TABLE DISPERSION */
 238             vfitab          += 0;
 239             Y                = vftab[vfitab];
 240             F                = vftab[vfitab+1];
 241             Geps             = vfeps*vftab[vfitab+2];
 242             Heps2            = vfeps*vfeps*vftab[vfitab+3];
 243             Fp               = F+Geps+Heps2;
 244             VV               = Y+vfeps*Fp;
 245             vvdw6            = c6_00*VV;
 246             FF               = Fp+Geps+2.0*Heps2;
 247             fvdw6            = c6_00*FF;
 248
 249             /* CUBIC SPLINE TABLE REPULSION */
 250             Y                = vftab[vfitab+4];
 251             F                = vftab[vfitab+5];
 252             Geps             = vfeps*vftab[vfitab+6];
 253             Heps2            = vfeps*vfeps*vftab[vfitab+7];
 254             Fp               = F+Geps+Heps2;
 255             VV               = Y+vfeps*Fp;
 256             vvdw12           = c12_00*VV;
 257             FF               = Fp+Geps+2.0*Heps2;
 258             fvdw12           = c12_00*FF;
 259             vvdw             = vvdw12+vvdw6;
 260             fvdw             = -(fvdw6+fvdw12)*vftabscale*rinv00;
 261
 262             /* Update potential sums from outer loop */
 263             vvdwsum         += vvdw;
 264
 265             fscal            = fvdw;
 266
 267             /* Calculate temporary vectorial force */
 268             tx               = fscal*dx00;
 269             ty               = fscal*dy00;
 270             tz               = fscal*dz00;
 271
 272             /* Update vectorial force */
 273             fix0            += tx;
 274             fiy0            += ty;
 275             fiz0            += tz;
 276             f[j_coord_offset+DIM*0+XX] -= tx;
 277             f[j_coord_offset+DIM*0+YY] -= ty;
 278             f[j_coord_offset+DIM*0+ZZ] -= tz;
 279
 280             /**************************
 281              * CALCULATE INTERACTIONS *
 282              **************************/
 283
 284             qq10             = iq1*jq0;
 285
 286             /* REACTION-FIELD ELECTROSTATICS */
 287             velec            = qq10*(rinv10+krf*rsq10-crf);
 288             felec            = qq10*(rinv10*rinvsq10-krf2);
 289
 290             /* Update potential sums from outer loop */
 291             velecsum        += velec;
 292
 293             fscal            = felec;
 294
 295             /* Calculate temporary vectorial force */
 296             tx               = fscal*dx10;
 297             ty               = fscal*dy10;
 298             tz               = fscal*dz10;
 299
 300             /* Update vectorial force */
 301             fix1            += tx;
 302             fiy1            += ty;
 303             fiz1            += 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             /**************************
 309              * CALCULATE INTERACTIONS *
 310              **************************/
 311
 312             qq20             = iq2*jq0;
 313
 314             /* REACTION-FIELD ELECTROSTATICS */
 315             velec            = qq20*(rinv20+krf*rsq20-crf);
 316             felec            = qq20*(rinv20*rinvsq20-krf2);
 317
 318             /* Update potential sums from outer loop */
 319             velecsum        += velec;
 320
 321             fscal            = felec;
 322
 323             /* Calculate temporary vectorial force */
 324             tx               = fscal*dx20;
 325             ty               = fscal*dy20;
 326             tz               = fscal*dz20;
 327
 328             /* Update vectorial force */
 329             fix2            += tx;
 330             fiy2            += ty;
 331             fiz2            += tz;
 332             f[j_coord_offset+DIM*0+XX] -= tx;
 333             f[j_coord_offset+DIM*0+YY] -= ty;
 334             f[j_coord_offset+DIM*0+ZZ] -= tz;
 335
 336             /**************************
 337              * CALCULATE INTERACTIONS *
 338              **************************/
 339
 340             qq30             = iq3*jq0;
 341
 342             /* REACTION-FIELD ELECTROSTATICS */
 343             velec            = qq30*(rinv30+krf*rsq30-crf);
 344             felec            = qq30*(rinv30*rinvsq30-krf2);
 345
 346             /* Update potential sums from outer loop */
 347             velecsum        += velec;
 348
 349             fscal            = felec;
 350
 351             /* Calculate temporary vectorial force */
 352             tx               = fscal*dx30;
 353             ty               = fscal*dy30;
 354             tz               = fscal*dz30;
 355
 356             /* Update vectorial force */
 357             fix3            += tx;
 358             fiy3            += ty;
 359             fiz3            += tz;
 360             f[j_coord_offset+DIM*0+XX] -= tx;
 361             f[j_coord_offset+DIM*0+YY] -= ty;
 362             f[j_coord_offset+DIM*0+ZZ] -= tz;
 363
 364             /* Inner loop uses 151 flops */
 365         }
 366         /* End of innermost loop */
 367
 368         tx = ty = tz = 0;
 369         f[i_coord_offset+DIM*0+XX] += fix0;
 370         f[i_coord_offset+DIM*0+YY] += fiy0;
 371         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 372         tx                         += fix0;
 373         ty                         += fiy0;
 374         tz                         += fiz0;
 375         f[i_coord_offset+DIM*1+XX] += fix1;
 376         f[i_coord_offset+DIM*1+YY] += fiy1;
 377         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 378         tx                         += fix1;
 379         ty                         += fiy1;
 380         tz                         += fiz1;
 381         f[i_coord_offset+DIM*2+XX] += fix2;
 382         f[i_coord_offset+DIM*2+YY] += fiy2;
 383         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 384         tx                         += fix2;
 385         ty                         += fiy2;
 386         tz                         += fiz2;
 387         f[i_coord_offset+DIM*3+XX] += fix3;
 388         f[i_coord_offset+DIM*3+YY] += fiy3;
 389         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 390         tx                         += fix3;
 391         ty                         += fiy3;
 392         tz                         += fiz3;
 393         fshift[i_shift_offset+XX]  += tx;
 394         fshift[i_shift_offset+YY]  += ty;
 395         fshift[i_shift_offset+ZZ]  += tz;
 396
 397         ggid                        = gid[iidx];
 398         /* Update potential energies */
 399         kernel_data->energygrp_elec[ggid] += velecsum;
 400         kernel_data->energygrp_vdw[ggid] += vvdwsum;
 401
 402         /* Increment number of inner iterations */
 403         inneriter                  += j_index_end - j_index_start;
 404
 405         /* Outer loop uses 41 flops */
 406     }
 407
 408     /* Increment number of outer iterations */
 409     outeriter        += nri;
 410
 411     /* Update outer/inner flops */
 412
 413     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_VF,outeriter*41 + inneriter*151);
 414 }
 415 /*
 416  * Gromacs nonbonded kernel:   nb_kernel_ElecRF_VdwCSTab_GeomW4P1_F_c
 417  * Electrostatics interaction: ReactionField
 418  * VdW interaction:            CubicSplineTable
 419  * Geometry:                   Water4-Particle
 420  * Calculate force/pot:        Force
 421  */
 422 void
 423 nb_kernel_ElecRF_VdwCSTab_GeomW4P1_F_c
 424                     (t_nblist                    * gmx_restrict       nlist,
 425                      rvec                        * gmx_restrict          xx,
 426                      rvec                        * gmx_restrict          ff,
 427                      t_forcerec                  * gmx_restrict          fr,
 428                      t_mdatoms                   * gmx_restrict     mdatoms,
 429                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 430                      t_nrnb                      * gmx_restrict        nrnb)
 431 {
 432     int              i_shift_offset,i_coord_offset,j_coord_offset;
 433     int              j_index_start,j_index_end;
 434     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 435     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 436     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 437     real             *shiftvec,*fshift,*x,*f;
 438     int              vdwioffset0;
 439     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 440     int              vdwioffset1;
 441     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 442     int              vdwioffset2;
 443     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 444     int              vdwioffset3;
 445     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
 446     int              vdwjidx0;
 447     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 448     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
 449     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
 450     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
 451     real             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
 452     real             velec,felec,velecsum,facel,crf,krf,krf2;
 453     real             *charge;
 454     int              nvdwtype;
 455     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
 456     int              *vdwtype;
 457     real             *vdwparam;
 458     int              vfitab;
 459     real             rt,vfeps,vftabscale,Y,F,Geps,Heps2,Fp,VV,FF;
 460     real             *vftab;
 461
 462     x                = xx[0];
 463     f                = ff[0];
 464
 465     nri              = nlist->nri;
 466     iinr             = nlist->iinr;
 467     jindex           = nlist->jindex;
 468     jjnr             = nlist->jjnr;
 469     shiftidx         = nlist->shift;
 470     gid              = nlist->gid;
 471     shiftvec         = fr->shift_vec[0];
 472     fshift           = fr->fshift[0];
 473     facel            = fr->epsfac;
 474     charge           = mdatoms->chargeA;
 475     krf              = fr->ic->k_rf;
 476     krf2             = krf*2.0;
 477     crf              = fr->ic->c_rf;
 478     nvdwtype         = fr->ntype;
 479     vdwparam         = fr->nbfp;
 480     vdwtype          = mdatoms->typeA;
 481
 482     vftab            = kernel_data->table_vdw->data;
 483     vftabscale       = kernel_data->table_vdw->scale;
 484
 485     /* Setup water-specific parameters */
 486     inr              = nlist->iinr[0];
 487     iq1              = facel*charge[inr+1];
 488     iq2              = facel*charge[inr+2];
 489     iq3              = facel*charge[inr+3];
 490     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 491
 492     outeriter        = 0;
 493     inneriter        = 0;
 494
 495     /* Start outer loop over neighborlists */
 496     for(iidx=0; iidx<nri; iidx++)
 497     {
 498         /* Load shift vector for this list */
 499         i_shift_offset   = DIM*shiftidx[iidx];
 500         shX              = shiftvec[i_shift_offset+XX];
 501         shY              = shiftvec[i_shift_offset+YY];
 502         shZ              = shiftvec[i_shift_offset+ZZ];
 503
 504         /* Load limits for loop over neighbors */
 505         j_index_start    = jindex[iidx];
 506         j_index_end      = jindex[iidx+1];
 507
 508         /* Get outer coordinate index */
 509         inr              = iinr[iidx];
 510         i_coord_offset   = DIM*inr;
 511
 512         /* Load i particle coords and add shift vector */
 513         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 514         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 515         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 516         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 517         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 518         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 519         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 520         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 521         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 522         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 523         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 524         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 525
 526         fix0             = 0.0;
 527         fiy0             = 0.0;
 528         fiz0             = 0.0;
 529         fix1             = 0.0;
 530         fiy1             = 0.0;
 531         fiz1             = 0.0;
 532         fix2             = 0.0;
 533         fiy2             = 0.0;
 534         fiz2             = 0.0;
 535         fix3             = 0.0;
 536         fiy3             = 0.0;
 537         fiz3             = 0.0;
 538
 539         /* Start inner kernel loop */
 540         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 541         {
 542             /* Get j neighbor index, and coordinate index */
 543             jnr              = jjnr[jidx];
 544             j_coord_offset   = DIM*jnr;
 545
 546             /* load j atom coordinates */
 547             jx0              = x[j_coord_offset+DIM*0+XX];
 548             jy0              = x[j_coord_offset+DIM*0+YY];
 549             jz0              = x[j_coord_offset+DIM*0+ZZ];
 550
 551             /* Calculate displacement vector */
 552             dx00             = ix0 - jx0;
 553             dy00             = iy0 - jy0;
 554             dz00             = iz0 - jz0;
 555             dx10             = ix1 - jx0;
 556             dy10             = iy1 - jy0;
 557             dz10             = iz1 - jz0;
 558             dx20             = ix2 - jx0;
 559             dy20             = iy2 - jy0;
 560             dz20             = iz2 - jz0;
 561             dx30             = ix3 - jx0;
 562             dy30             = iy3 - jy0;
 563             dz30             = iz3 - jz0;
 564
 565             /* Calculate squared distance and things based on it */
 566             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 567             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 568             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 569             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 570
 571             rinv00           = gmx_invsqrt(rsq00);
 572             rinv10           = gmx_invsqrt(rsq10);
 573             rinv20           = gmx_invsqrt(rsq20);
 574             rinv30           = gmx_invsqrt(rsq30);
 575
 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         = 2*vdwtype[jnr+0];
 583
 584             /**************************
 585              * CALCULATE INTERACTIONS *
 586              **************************/
 587
 588             r00              = rsq00*rinv00;
 589
 590             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 591             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 592
 593             /* Calculate table index by multiplying r with table scale and truncate to integer */
 594             rt               = r00*vftabscale;
 595             vfitab           = rt;
 596             vfeps            = rt-vfitab;
 597             vfitab           = 2*4*vfitab;
 598
 599             /* CUBIC SPLINE TABLE DISPERSION */
 600             vfitab          += 0;
 601             F                = vftab[vfitab+1];
 602             Geps             = vfeps*vftab[vfitab+2];
 603             Heps2            = vfeps*vfeps*vftab[vfitab+3];
 604             Fp               = F+Geps+Heps2;
 605             FF               = Fp+Geps+2.0*Heps2;
 606             fvdw6            = c6_00*FF;
 607
 608             /* CUBIC SPLINE TABLE REPULSION */
 609             F                = vftab[vfitab+5];
 610             Geps             = vfeps*vftab[vfitab+6];
 611             Heps2            = vfeps*vfeps*vftab[vfitab+7];
 612             Fp               = F+Geps+Heps2;
 613             FF               = Fp+Geps+2.0*Heps2;
 614             fvdw12           = c12_00*FF;
 615             fvdw             = -(fvdw6+fvdw12)*vftabscale*rinv00;
 616
 617             fscal            = fvdw;
 618
 619             /* Calculate temporary vectorial force */
 620             tx               = fscal*dx00;
 621             ty               = fscal*dy00;
 622             tz               = fscal*dz00;
 623
 624             /* Update vectorial force */
 625             fix0            += tx;
 626             fiy0            += ty;
 627             fiz0            += tz;
 628             f[j_coord_offset+DIM*0+XX] -= tx;
 629             f[j_coord_offset+DIM*0+YY] -= ty;
 630             f[j_coord_offset+DIM*0+ZZ] -= tz;
 631
 632             /**************************
 633              * CALCULATE INTERACTIONS *
 634              **************************/
 635
 636             qq10             = iq1*jq0;
 637
 638             /* REACTION-FIELD ELECTROSTATICS */
 639             felec            = qq10*(rinv10*rinvsq10-krf2);
 640
 641             fscal            = felec;
 642
 643             /* Calculate temporary vectorial force */
 644             tx               = fscal*dx10;
 645             ty               = fscal*dy10;
 646             tz               = fscal*dz10;
 647
 648             /* Update vectorial force */
 649             fix1            += tx;
 650             fiy1            += ty;
 651             fiz1            += tz;
 652             f[j_coord_offset+DIM*0+XX] -= tx;
 653             f[j_coord_offset+DIM*0+YY] -= ty;
 654             f[j_coord_offset+DIM*0+ZZ] -= tz;
 655
 656             /**************************
 657              * CALCULATE INTERACTIONS *
 658              **************************/
 659
 660             qq20             = iq2*jq0;
 661
 662             /* REACTION-FIELD ELECTROSTATICS */
 663             felec            = qq20*(rinv20*rinvsq20-krf2);
 664
 665             fscal            = felec;
 666
 667             /* Calculate temporary vectorial force */
 668             tx               = fscal*dx20;
 669             ty               = fscal*dy20;
 670             tz               = fscal*dz20;
 671
 672             /* Update vectorial force */
 673             fix2            += tx;
 674             fiy2            += ty;
 675             fiz2            += tz;
 676             f[j_coord_offset+DIM*0+XX] -= tx;
 677             f[j_coord_offset+DIM*0+YY] -= ty;
 678             f[j_coord_offset+DIM*0+ZZ] -= tz;
 679
 680             /**************************
 681              * CALCULATE INTERACTIONS *
 682              **************************/
 683
 684             qq30             = iq3*jq0;
 685
 686             /* REACTION-FIELD ELECTROSTATICS */
 687             felec            = qq30*(rinv30*rinvsq30-krf2);
 688
 689             fscal            = felec;
 690
 691             /* Calculate temporary vectorial force */
 692             tx               = fscal*dx30;
 693             ty               = fscal*dy30;
 694             tz               = fscal*dz30;
 695
 696             /* Update vectorial force */
 697             fix3            += tx;
 698             fiy3            += ty;
 699             fiz3            += tz;
 700             f[j_coord_offset+DIM*0+XX] -= tx;
 701             f[j_coord_offset+DIM*0+YY] -= ty;
 702             f[j_coord_offset+DIM*0+ZZ] -= tz;
 703
 704             /* Inner loop uses 128 flops */
 705         }
 706         /* End of innermost loop */
 707
 708         tx = ty = tz = 0;
 709         f[i_coord_offset+DIM*0+XX] += fix0;
 710         f[i_coord_offset+DIM*0+YY] += fiy0;
 711         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 712         tx                         += fix0;
 713         ty                         += fiy0;
 714         tz                         += fiz0;
 715         f[i_coord_offset+DIM*1+XX] += fix1;
 716         f[i_coord_offset+DIM*1+YY] += fiy1;
 717         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 718         tx                         += fix1;
 719         ty                         += fiy1;
 720         tz                         += fiz1;
 721         f[i_coord_offset+DIM*2+XX] += fix2;
 722         f[i_coord_offset+DIM*2+YY] += fiy2;
 723         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 724         tx                         += fix2;
 725         ty                         += fiy2;
 726         tz                         += fiz2;
 727         f[i_coord_offset+DIM*3+XX] += fix3;
 728         f[i_coord_offset+DIM*3+YY] += fiy3;
 729         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 730         tx                         += fix3;
 731         ty                         += fiy3;
 732         tz                         += fiz3;
 733         fshift[i_shift_offset+XX]  += tx;
 734         fshift[i_shift_offset+YY]  += ty;
 735         fshift[i_shift_offset+ZZ]  += tz;
 736
 737         /* Increment number of inner iterations */
 738         inneriter                  += j_index_end - j_index_start;
 739
 740         /* Outer loop uses 39 flops */
 741     }
 742
 743     /* Increment number of outer iterations */
 744     outeriter        += nri;
 745
 746     /* Update outer/inner flops */
 747
 748     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_F,outeriter*39 + inneriter*128);
 749 }