src/gromacs/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecEwSh_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_ElecEwSh_VdwLJSh_GeomW4P1_VF_c
  51  * Electrostatics interaction: Ewald
  52  * VdW interaction:            LennardJones
  53  * Geometry:                   Water4-Particle
  54  * Calculate force/pot:        PotentialAndForce
  55  */
  56 void
  57 nb_kernel_ElecEwSh_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     int              ewitab;
  93     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
  94     real             *ewtab;
  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     nvdwtype         = fr->ntype;
 110     vdwparam         = fr->nbfp;
 111     vdwtype          = mdatoms->typeA;
 112
 113     sh_ewald         = fr->ic->sh_ewald;
 114     ewtab            = fr->ic->tabq_coul_FDV0;
 115     ewtabscale       = fr->ic->tabq_scale;
 116     ewtabhalfspace   = 0.5/ewtabscale;
 117
 118     /* Setup water-specific parameters */
 119     inr              = nlist->iinr[0];
 120     iq1              = facel*charge[inr+1];
 121     iq2              = facel*charge[inr+2];
 122     iq3              = facel*charge[inr+3];
 123     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 124
 125     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 126     rcutoff          = fr->rcoulomb;
 127     rcutoff2         = rcutoff*rcutoff;
 128
 129     sh_vdw_invrcut6  = fr->ic->sh_invrc6;
 130     rvdw             = fr->rvdw;
 131
 132     outeriter        = 0;
 133     inneriter        = 0;
 134
 135     /* Start outer loop over neighborlists */
 136     for(iidx=0; iidx<nri; iidx++)
 137     {
 138         /* Load shift vector for this list */
 139         i_shift_offset   = DIM*shiftidx[iidx];
 140         shX              = shiftvec[i_shift_offset+XX];
 141         shY              = shiftvec[i_shift_offset+YY];
 142         shZ              = shiftvec[i_shift_offset+ZZ];
 143
 144         /* Load limits for loop over neighbors */
 145         j_index_start    = jindex[iidx];
 146         j_index_end      = jindex[iidx+1];
 147
 148         /* Get outer coordinate index */
 149         inr              = iinr[iidx];
 150         i_coord_offset   = DIM*inr;
 151
 152         /* Load i particle coords and add shift vector */
 153         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 154         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 155         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 156         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 157         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 158         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 159         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 160         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 161         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 162         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 163         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 164         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 165
 166         fix0             = 0.0;
 167         fiy0             = 0.0;
 168         fiz0             = 0.0;
 169         fix1             = 0.0;
 170         fiy1             = 0.0;
 171         fiz1             = 0.0;
 172         fix2             = 0.0;
 173         fiy2             = 0.0;
 174         fiz2             = 0.0;
 175         fix3             = 0.0;
 176         fiy3             = 0.0;
 177         fiz3             = 0.0;
 178
 179         /* Reset potential sums */
 180         velecsum         = 0.0;
 181         vvdwsum          = 0.0;
 182
 183         /* Start inner kernel loop */
 184         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 185         {
 186             /* Get j neighbor index, and coordinate index */
 187             jnr              = jjnr[jidx];
 188             j_coord_offset   = DIM*jnr;
 189
 190             /* load j atom coordinates */
 191             jx0              = x[j_coord_offset+DIM*0+XX];
 192             jy0              = x[j_coord_offset+DIM*0+YY];
 193             jz0              = x[j_coord_offset+DIM*0+ZZ];
 194
 195             /* Calculate displacement vector */
 196             dx00             = ix0 - jx0;
 197             dy00             = iy0 - jy0;
 198             dz00             = iz0 - jz0;
 199             dx10             = ix1 - jx0;
 200             dy10             = iy1 - jy0;
 201             dz10             = iz1 - jz0;
 202             dx20             = ix2 - jx0;
 203             dy20             = iy2 - jy0;
 204             dz20             = iz2 - jz0;
 205             dx30             = ix3 - jx0;
 206             dy30             = iy3 - jy0;
 207             dz30             = iz3 - jz0;
 208
 209             /* Calculate squared distance and things based on it */
 210             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 211             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 212             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 213             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 214
 215             rinv10           = gmx_invsqrt(rsq10);
 216             rinv20           = gmx_invsqrt(rsq20);
 217             rinv30           = gmx_invsqrt(rsq30);
 218
 219             rinvsq00         = 1.0/rsq00;
 220             rinvsq10         = rinv10*rinv10;
 221             rinvsq20         = rinv20*rinv20;
 222             rinvsq30         = rinv30*rinv30;
 223
 224             /* Load parameters for j particles */
 225             jq0              = charge[jnr+0];
 226             vdwjidx0         = 2*vdwtype[jnr+0];
 227
 228             /**************************
 229              * CALCULATE INTERACTIONS *
 230              **************************/
 231
 232             if (rsq00<rcutoff2)
 233             {
 234
 235             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 236             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 237
 238             /* LENNARD-JONES DISPERSION/REPULSION */
 239
 240             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 241             vvdw6            = c6_00*rinvsix;
 242             vvdw12           = c12_00*rinvsix*rinvsix;
 243             vvdw             = (vvdw12 - c12_00*sh_vdw_invrcut6*sh_vdw_invrcut6)*(1.0/12.0) - (vvdw6 - c6_00*sh_vdw_invrcut6)*(1.0/6.0);
 244             fvdw             = (vvdw12-vvdw6)*rinvsq00;
 245
 246             /* Update potential sums from outer loop */
 247             vvdwsum         += vvdw;
 248
 249             fscal            = fvdw;
 250
 251             /* Calculate temporary vectorial force */
 252             tx               = fscal*dx00;
 253             ty               = fscal*dy00;
 254             tz               = fscal*dz00;
 255
 256             /* Update vectorial force */
 257             fix0            += tx;
 258             fiy0            += ty;
 259             fiz0            += tz;
 260             f[j_coord_offset+DIM*0+XX] -= tx;
 261             f[j_coord_offset+DIM*0+YY] -= ty;
 262             f[j_coord_offset+DIM*0+ZZ] -= tz;
 263
 264             }
 265
 266             /**************************
 267              * CALCULATE INTERACTIONS *
 268              **************************/
 269
 270             if (rsq10<rcutoff2)
 271             {
 272
 273             r10              = rsq10*rinv10;
 274
 275             qq10             = iq1*jq0;
 276
 277             /* EWALD ELECTROSTATICS */
 278
 279             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 280             ewrt             = r10*ewtabscale;
 281             ewitab           = ewrt;
 282             eweps            = ewrt-ewitab;
 283             ewitab           = 4*ewitab;
 284             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 285             velec            = qq10*((rinv10-sh_ewald)-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 286             felec            = qq10*rinv10*(rinvsq10-felec);
 287
 288             /* Update potential sums from outer loop */
 289             velecsum        += velec;
 290
 291             fscal            = felec;
 292
 293             /* Calculate temporary vectorial force */
 294             tx               = fscal*dx10;
 295             ty               = fscal*dy10;
 296             tz               = fscal*dz10;
 297
 298             /* Update vectorial force */
 299             fix1            += tx;
 300             fiy1            += ty;
 301             fiz1            += tz;
 302             f[j_coord_offset+DIM*0+XX] -= tx;
 303             f[j_coord_offset+DIM*0+YY] -= ty;
 304             f[j_coord_offset+DIM*0+ZZ] -= tz;
 305
 306             }
 307
 308             /**************************
 309              * CALCULATE INTERACTIONS *
 310              **************************/
 311
 312             if (rsq20<rcutoff2)
 313             {
 314
 315             r20              = rsq20*rinv20;
 316
 317             qq20             = iq2*jq0;
 318
 319             /* EWALD ELECTROSTATICS */
 320
 321             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 322             ewrt             = r20*ewtabscale;
 323             ewitab           = ewrt;
 324             eweps            = ewrt-ewitab;
 325             ewitab           = 4*ewitab;
 326             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 327             velec            = qq20*((rinv20-sh_ewald)-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 328             felec            = qq20*rinv20*(rinvsq20-felec);
 329
 330             /* Update potential sums from outer loop */
 331             velecsum        += velec;
 332
 333             fscal            = felec;
 334
 335             /* Calculate temporary vectorial force */
 336             tx               = fscal*dx20;
 337             ty               = fscal*dy20;
 338             tz               = fscal*dz20;
 339
 340             /* Update vectorial force */
 341             fix2            += tx;
 342             fiy2            += ty;
 343             fiz2            += tz;
 344             f[j_coord_offset+DIM*0+XX] -= tx;
 345             f[j_coord_offset+DIM*0+YY] -= ty;
 346             f[j_coord_offset+DIM*0+ZZ] -= tz;
 347
 348             }
 349
 350             /**************************
 351              * CALCULATE INTERACTIONS *
 352              **************************/
 353
 354             if (rsq30<rcutoff2)
 355             {
 356
 357             r30              = rsq30*rinv30;
 358
 359             qq30             = iq3*jq0;
 360
 361             /* EWALD ELECTROSTATICS */
 362
 363             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 364             ewrt             = r30*ewtabscale;
 365             ewitab           = ewrt;
 366             eweps            = ewrt-ewitab;
 367             ewitab           = 4*ewitab;
 368             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 369             velec            = qq30*((rinv30-sh_ewald)-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 370             felec            = qq30*rinv30*(rinvsq30-felec);
 371
 372             /* Update potential sums from outer loop */
 373             velecsum        += velec;
 374
 375             fscal            = felec;
 376
 377             /* Calculate temporary vectorial force */
 378             tx               = fscal*dx30;
 379             ty               = fscal*dy30;
 380             tz               = fscal*dz30;
 381
 382             /* Update vectorial force */
 383             fix3            += tx;
 384             fiy3            += ty;
 385             fiz3            += tz;
 386             f[j_coord_offset+DIM*0+XX] -= tx;
 387             f[j_coord_offset+DIM*0+YY] -= ty;
 388             f[j_coord_offset+DIM*0+ZZ] -= tz;
 389
 390             }
 391
 392             /* Inner loop uses 163 flops */
 393         }
 394         /* End of innermost loop */
 395
 396         tx = ty = tz = 0;
 397         f[i_coord_offset+DIM*0+XX] += fix0;
 398         f[i_coord_offset+DIM*0+YY] += fiy0;
 399         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 400         tx                         += fix0;
 401         ty                         += fiy0;
 402         tz                         += fiz0;
 403         f[i_coord_offset+DIM*1+XX] += fix1;
 404         f[i_coord_offset+DIM*1+YY] += fiy1;
 405         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 406         tx                         += fix1;
 407         ty                         += fiy1;
 408         tz                         += fiz1;
 409         f[i_coord_offset+DIM*2+XX] += fix2;
 410         f[i_coord_offset+DIM*2+YY] += fiy2;
 411         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 412         tx                         += fix2;
 413         ty                         += fiy2;
 414         tz                         += fiz2;
 415         f[i_coord_offset+DIM*3+XX] += fix3;
 416         f[i_coord_offset+DIM*3+YY] += fiy3;
 417         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 418         tx                         += fix3;
 419         ty                         += fiy3;
 420         tz                         += fiz3;
 421         fshift[i_shift_offset+XX]  += tx;
 422         fshift[i_shift_offset+YY]  += ty;
 423         fshift[i_shift_offset+ZZ]  += tz;
 424
 425         ggid                        = gid[iidx];
 426         /* Update potential energies */
 427         kernel_data->energygrp_elec[ggid] += velecsum;
 428         kernel_data->energygrp_vdw[ggid] += vvdwsum;
 429
 430         /* Increment number of inner iterations */
 431         inneriter                  += j_index_end - j_index_start;
 432
 433         /* Outer loop uses 41 flops */
 434     }
 435
 436     /* Increment number of outer iterations */
 437     outeriter        += nri;
 438
 439     /* Update outer/inner flops */
 440
 441     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_VF,outeriter*41 + inneriter*163);
 442 }
 443 /*
 444  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSh_VdwLJSh_GeomW4P1_F_c
 445  * Electrostatics interaction: Ewald
 446  * VdW interaction:            LennardJones
 447  * Geometry:                   Water4-Particle
 448  * Calculate force/pot:        Force
 449  */
 450 void
 451 nb_kernel_ElecEwSh_VdwLJSh_GeomW4P1_F_c
 452                     (t_nblist                    * gmx_restrict       nlist,
 453                      rvec                        * gmx_restrict          xx,
 454                      rvec                        * gmx_restrict          ff,
 455                      t_forcerec                  * gmx_restrict          fr,
 456                      t_mdatoms                   * gmx_restrict     mdatoms,
 457                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 458                      t_nrnb                      * gmx_restrict        nrnb)
 459 {
 460     int              i_shift_offset,i_coord_offset,j_coord_offset;
 461     int              j_index_start,j_index_end;
 462     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 463     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 464     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 465     real             *shiftvec,*fshift,*x,*f;
 466     int              vdwioffset0;
 467     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 468     int              vdwioffset1;
 469     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 470     int              vdwioffset2;
 471     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 472     int              vdwioffset3;
 473     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
 474     int              vdwjidx0;
 475     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 476     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
 477     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
 478     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
 479     real             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
 480     real             velec,felec,velecsum,facel,crf,krf,krf2;
 481     real             *charge;
 482     int              nvdwtype;
 483     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
 484     int              *vdwtype;
 485     real             *vdwparam;
 486     int              ewitab;
 487     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
 488     real             *ewtab;
 489
 490     x                = xx[0];
 491     f                = ff[0];
 492
 493     nri              = nlist->nri;
 494     iinr             = nlist->iinr;
 495     jindex           = nlist->jindex;
 496     jjnr             = nlist->jjnr;
 497     shiftidx         = nlist->shift;
 498     gid              = nlist->gid;
 499     shiftvec         = fr->shift_vec[0];
 500     fshift           = fr->fshift[0];
 501     facel            = fr->epsfac;
 502     charge           = mdatoms->chargeA;
 503     nvdwtype         = fr->ntype;
 504     vdwparam         = fr->nbfp;
 505     vdwtype          = mdatoms->typeA;
 506
 507     sh_ewald         = fr->ic->sh_ewald;
 508     ewtab            = fr->ic->tabq_coul_F;
 509     ewtabscale       = fr->ic->tabq_scale;
 510     ewtabhalfspace   = 0.5/ewtabscale;
 511
 512     /* Setup water-specific parameters */
 513     inr              = nlist->iinr[0];
 514     iq1              = facel*charge[inr+1];
 515     iq2              = facel*charge[inr+2];
 516     iq3              = facel*charge[inr+3];
 517     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 518
 519     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 520     rcutoff          = fr->rcoulomb;
 521     rcutoff2         = rcutoff*rcutoff;
 522
 523     sh_vdw_invrcut6  = fr->ic->sh_invrc6;
 524     rvdw             = fr->rvdw;
 525
 526     outeriter        = 0;
 527     inneriter        = 0;
 528
 529     /* Start outer loop over neighborlists */
 530     for(iidx=0; iidx<nri; iidx++)
 531     {
 532         /* Load shift vector for this list */
 533         i_shift_offset   = DIM*shiftidx[iidx];
 534         shX              = shiftvec[i_shift_offset+XX];
 535         shY              = shiftvec[i_shift_offset+YY];
 536         shZ              = shiftvec[i_shift_offset+ZZ];
 537
 538         /* Load limits for loop over neighbors */
 539         j_index_start    = jindex[iidx];
 540         j_index_end      = jindex[iidx+1];
 541
 542         /* Get outer coordinate index */
 543         inr              = iinr[iidx];
 544         i_coord_offset   = DIM*inr;
 545
 546         /* Load i particle coords and add shift vector */
 547         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 548         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 549         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 550         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 551         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 552         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 553         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 554         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 555         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 556         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 557         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 558         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 559
 560         fix0             = 0.0;
 561         fiy0             = 0.0;
 562         fiz0             = 0.0;
 563         fix1             = 0.0;
 564         fiy1             = 0.0;
 565         fiz1             = 0.0;
 566         fix2             = 0.0;
 567         fiy2             = 0.0;
 568         fiz2             = 0.0;
 569         fix3             = 0.0;
 570         fiy3             = 0.0;
 571         fiz3             = 0.0;
 572
 573         /* Start inner kernel loop */
 574         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 575         {
 576             /* Get j neighbor index, and coordinate index */
 577             jnr              = jjnr[jidx];
 578             j_coord_offset   = DIM*jnr;
 579
 580             /* load j atom coordinates */
 581             jx0              = x[j_coord_offset+DIM*0+XX];
 582             jy0              = x[j_coord_offset+DIM*0+YY];
 583             jz0              = x[j_coord_offset+DIM*0+ZZ];
 584
 585             /* Calculate displacement vector */
 586             dx00             = ix0 - jx0;
 587             dy00             = iy0 - jy0;
 588             dz00             = iz0 - jz0;
 589             dx10             = ix1 - jx0;
 590             dy10             = iy1 - jy0;
 591             dz10             = iz1 - jz0;
 592             dx20             = ix2 - jx0;
 593             dy20             = iy2 - jy0;
 594             dz20             = iz2 - jz0;
 595             dx30             = ix3 - jx0;
 596             dy30             = iy3 - jy0;
 597             dz30             = iz3 - jz0;
 598
 599             /* Calculate squared distance and things based on it */
 600             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 601             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 602             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 603             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 604
 605             rinv10           = gmx_invsqrt(rsq10);
 606             rinv20           = gmx_invsqrt(rsq20);
 607             rinv30           = gmx_invsqrt(rsq30);
 608
 609             rinvsq00         = 1.0/rsq00;
 610             rinvsq10         = rinv10*rinv10;
 611             rinvsq20         = rinv20*rinv20;
 612             rinvsq30         = rinv30*rinv30;
 613
 614             /* Load parameters for j particles */
 615             jq0              = charge[jnr+0];
 616             vdwjidx0         = 2*vdwtype[jnr+0];
 617
 618             /**************************
 619              * CALCULATE INTERACTIONS *
 620              **************************/
 621
 622             if (rsq00<rcutoff2)
 623             {
 624
 625             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 626             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 627
 628             /* LENNARD-JONES DISPERSION/REPULSION */
 629
 630             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 631             fvdw             = (c12_00*rinvsix-c6_00)*rinvsix*rinvsq00;
 632
 633             fscal            = fvdw;
 634
 635             /* Calculate temporary vectorial force */
 636             tx               = fscal*dx00;
 637             ty               = fscal*dy00;
 638             tz               = fscal*dz00;
 639
 640             /* Update vectorial force */
 641             fix0            += tx;
 642             fiy0            += ty;
 643             fiz0            += 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 (rsq10<rcutoff2)
 655             {
 656
 657             r10              = rsq10*rinv10;
 658
 659             qq10             = iq1*jq0;
 660
 661             /* EWALD ELECTROSTATICS */
 662
 663             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 664             ewrt             = r10*ewtabscale;
 665             ewitab           = ewrt;
 666             eweps            = ewrt-ewitab;
 667             felec            = (1.0-eweps)*ewtab[ewitab]+eweps*ewtab[ewitab+1];
 668             felec            = qq10*rinv10*(rinvsq10-felec);
 669
 670             fscal            = felec;
 671
 672             /* Calculate temporary vectorial force */
 673             tx               = fscal*dx10;
 674             ty               = fscal*dy10;
 675             tz               = fscal*dz10;
 676
 677             /* Update vectorial force */
 678             fix1            += tx;
 679             fiy1            += ty;
 680             fiz1            += tz;
 681             f[j_coord_offset+DIM*0+XX] -= tx;
 682             f[j_coord_offset+DIM*0+YY] -= ty;
 683             f[j_coord_offset+DIM*0+ZZ] -= tz;
 684
 685             }
 686
 687             /**************************
 688              * CALCULATE INTERACTIONS *
 689              **************************/
 690
 691             if (rsq20<rcutoff2)
 692             {
 693
 694             r20              = rsq20*rinv20;
 695
 696             qq20             = iq2*jq0;
 697
 698             /* EWALD ELECTROSTATICS */
 699
 700             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 701             ewrt             = r20*ewtabscale;
 702             ewitab           = ewrt;
 703             eweps            = ewrt-ewitab;
 704             felec            = (1.0-eweps)*ewtab[ewitab]+eweps*ewtab[ewitab+1];
 705             felec            = qq20*rinv20*(rinvsq20-felec);
 706
 707             fscal            = felec;
 708
 709             /* Calculate temporary vectorial force */
 710             tx               = fscal*dx20;
 711             ty               = fscal*dy20;
 712             tz               = fscal*dz20;
 713
 714             /* Update vectorial force */
 715             fix2            += tx;
 716             fiy2            += ty;
 717             fiz2            += tz;
 718             f[j_coord_offset+DIM*0+XX] -= tx;
 719             f[j_coord_offset+DIM*0+YY] -= ty;
 720             f[j_coord_offset+DIM*0+ZZ] -= tz;
 721
 722             }
 723
 724             /**************************
 725              * CALCULATE INTERACTIONS *
 726              **************************/
 727
 728             if (rsq30<rcutoff2)
 729             {
 730
 731             r30              = rsq30*rinv30;
 732
 733             qq30             = iq3*jq0;
 734
 735             /* EWALD ELECTROSTATICS */
 736
 737             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 738             ewrt             = r30*ewtabscale;
 739             ewitab           = ewrt;
 740             eweps            = ewrt-ewitab;
 741             felec            = (1.0-eweps)*ewtab[ewitab]+eweps*ewtab[ewitab+1];
 742             felec            = qq30*rinv30*(rinvsq30-felec);
 743
 744             fscal            = felec;
 745
 746             /* Calculate temporary vectorial force */
 747             tx               = fscal*dx30;
 748             ty               = fscal*dy30;
 749             tz               = fscal*dz30;
 750
 751             /* Update vectorial force */
 752             fix3            += tx;
 753             fiy3            += ty;
 754             fiz3            += tz;
 755             f[j_coord_offset+DIM*0+XX] -= tx;
 756             f[j_coord_offset+DIM*0+YY] -= ty;
 757             f[j_coord_offset+DIM*0+ZZ] -= tz;
 758
 759             }
 760
 761             /* Inner loop uses 129 flops */
 762         }
 763         /* End of innermost loop */
 764
 765         tx = ty = tz = 0;
 766         f[i_coord_offset+DIM*0+XX] += fix0;
 767         f[i_coord_offset+DIM*0+YY] += fiy0;
 768         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 769         tx                         += fix0;
 770         ty                         += fiy0;
 771         tz                         += fiz0;
 772         f[i_coord_offset+DIM*1+XX] += fix1;
 773         f[i_coord_offset+DIM*1+YY] += fiy1;
 774         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 775         tx                         += fix1;
 776         ty                         += fiy1;
 777         tz                         += fiz1;
 778         f[i_coord_offset+DIM*2+XX] += fix2;
 779         f[i_coord_offset+DIM*2+YY] += fiy2;
 780         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 781         tx                         += fix2;
 782         ty                         += fiy2;
 783         tz                         += fiz2;
 784         f[i_coord_offset+DIM*3+XX] += fix3;
 785         f[i_coord_offset+DIM*3+YY] += fiy3;
 786         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 787         tx                         += fix3;
 788         ty                         += fiy3;
 789         tz                         += fiz3;
 790         fshift[i_shift_offset+XX]  += tx;
 791         fshift[i_shift_offset+YY]  += ty;
 792         fshift[i_shift_offset+ZZ]  += tz;
 793
 794         /* Increment number of inner iterations */
 795         inneriter                  += j_index_end - j_index_start;
 796
 797         /* Outer loop uses 39 flops */
 798     }
 799
 800     /* Increment number of outer iterations */
 801     outeriter        += nri;
 802
 803     /* Update outer/inner flops */
 804
 805     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_F,outeriter*39 + inneriter*129);
 806 }