src/gromacs/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecEwSh_VdwLJEwSh_GeomW4P1_c.c

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2012,2013,2014, by the GROMACS development team, led by
   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
   6  * and including many others, as listed in the AUTHORS file in the
   7  * top-level source directory and at http://www.gromacs.org.
   8  *
   9  * GROMACS is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1
  12  * of the License, or (at your option) any later version.
  13  *
  14  * GROMACS is distributed in the hope that it will be useful,
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  17  * Lesser General Public License for more details.
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  34  */
  35 /*
  36  * Note: this file was generated by the GROMACS c kernel generator.
  37  */
  38 #include "config.h"
  39
  40 #include <math.h>
  41
  42 #include "../nb_kernel.h"
  43 #include "types/simple.h"
  44 #include "gromacs/math/vec.h"
  45 #include "nrnb.h"
  46
  47 /*
  48  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSh_VdwLJEwSh_GeomW4P1_VF_c
  49  * Electrostatics interaction: Ewald
  50  * VdW interaction:            LJEwald
  51  * Geometry:                   Water4-Particle
  52  * Calculate force/pot:        PotentialAndForce
  53  */
  54 void
  55 nb_kernel_ElecEwSh_VdwLJEwSh_GeomW4P1_VF_c
  56                     (t_nblist                    * gmx_restrict       nlist,
  57                      rvec                        * gmx_restrict          xx,
  58                      rvec                        * gmx_restrict          ff,
  59                      t_forcerec                  * gmx_restrict          fr,
  60                      t_mdatoms                   * gmx_restrict     mdatoms,
  61                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
  62                      t_nrnb                      * gmx_restrict        nrnb)
  63 {
  64     int              i_shift_offset,i_coord_offset,j_coord_offset;
  65     int              j_index_start,j_index_end;
  66     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
  67     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
  68     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  69     real             *shiftvec,*fshift,*x,*f;
  70     int              vdwioffset0;
  71     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  72     int              vdwioffset1;
  73     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
  74     int              vdwioffset2;
  75     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
  76     int              vdwioffset3;
  77     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
  78     int              vdwjidx0;
  79     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  80     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
  81     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
  82     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
  83     real             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
  84     real             velec,felec,velecsum,facel,crf,krf,krf2;
  85     real             *charge;
  86     int              nvdwtype;
  87     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
  88     int              *vdwtype;
  89     real             *vdwparam;
  90     real             c6grid_00;
  91     real             c6grid_10;
  92     real             c6grid_20;
  93     real             c6grid_30;
  94     real             ewclj,ewclj2,ewclj6,ewcljrsq,poly,exponent,sh_lj_ewald;
  95     real             *vdwgridparam;
  96     int              ewitab;
  97     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
  98     real             *ewtab;
  99
 100     x                = xx[0];
 101     f                = ff[0];
 102
 103     nri              = nlist->nri;
 104     iinr             = nlist->iinr;
 105     jindex           = nlist->jindex;
 106     jjnr             = nlist->jjnr;
 107     shiftidx         = nlist->shift;
 108     gid              = nlist->gid;
 109     shiftvec         = fr->shift_vec[0];
 110     fshift           = fr->fshift[0];
 111     facel            = fr->epsfac;
 112     charge           = mdatoms->chargeA;
 113     nvdwtype         = fr->ntype;
 114     vdwparam         = fr->nbfp;
 115     vdwtype          = mdatoms->typeA;
 116     vdwgridparam     = fr->ljpme_c6grid;
 117     ewclj            = fr->ewaldcoeff_lj;
 118     sh_lj_ewald      = fr->ic->sh_lj_ewald;
 119     ewclj2           = ewclj*ewclj;
 120     ewclj6           = ewclj2*ewclj2*ewclj2;
 121
 122     sh_ewald         = fr->ic->sh_ewald;
 123     ewtab            = fr->ic->tabq_coul_FDV0;
 124     ewtabscale       = fr->ic->tabq_scale;
 125     ewtabhalfspace   = 0.5/ewtabscale;
 126
 127     /* Setup water-specific parameters */
 128     inr              = nlist->iinr[0];
 129     iq1              = facel*charge[inr+1];
 130     iq2              = facel*charge[inr+2];
 131     iq3              = facel*charge[inr+3];
 132     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 133
 134     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 135     rcutoff          = fr->rcoulomb;
 136     rcutoff2         = rcutoff*rcutoff;
 137
 138     sh_vdw_invrcut6  = fr->ic->sh_invrc6;
 139     rvdw             = fr->rvdw;
 140
 141     outeriter        = 0;
 142     inneriter        = 0;
 143
 144     /* Start outer loop over neighborlists */
 145     for(iidx=0; iidx<nri; iidx++)
 146     {
 147         /* Load shift vector for this list */
 148         i_shift_offset   = DIM*shiftidx[iidx];
 149         shX              = shiftvec[i_shift_offset+XX];
 150         shY              = shiftvec[i_shift_offset+YY];
 151         shZ              = shiftvec[i_shift_offset+ZZ];
 152
 153         /* Load limits for loop over neighbors */
 154         j_index_start    = jindex[iidx];
 155         j_index_end      = jindex[iidx+1];
 156
 157         /* Get outer coordinate index */
 158         inr              = iinr[iidx];
 159         i_coord_offset   = DIM*inr;
 160
 161         /* Load i particle coords and add shift vector */
 162         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 163         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 164         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 165         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 166         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 167         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 168         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 169         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 170         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 171         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 172         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 173         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 174
 175         fix0             = 0.0;
 176         fiy0             = 0.0;
 177         fiz0             = 0.0;
 178         fix1             = 0.0;
 179         fiy1             = 0.0;
 180         fiz1             = 0.0;
 181         fix2             = 0.0;
 182         fiy2             = 0.0;
 183         fiz2             = 0.0;
 184         fix3             = 0.0;
 185         fiy3             = 0.0;
 186         fiz3             = 0.0;
 187
 188         /* Reset potential sums */
 189         velecsum         = 0.0;
 190         vvdwsum          = 0.0;
 191
 192         /* Start inner kernel loop */
 193         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 194         {
 195             /* Get j neighbor index, and coordinate index */
 196             jnr              = jjnr[jidx];
 197             j_coord_offset   = DIM*jnr;
 198
 199             /* load j atom coordinates */
 200             jx0              = x[j_coord_offset+DIM*0+XX];
 201             jy0              = x[j_coord_offset+DIM*0+YY];
 202             jz0              = x[j_coord_offset+DIM*0+ZZ];
 203
 204             /* Calculate displacement vector */
 205             dx00             = ix0 - jx0;
 206             dy00             = iy0 - jy0;
 207             dz00             = iz0 - jz0;
 208             dx10             = ix1 - jx0;
 209             dy10             = iy1 - jy0;
 210             dz10             = iz1 - jz0;
 211             dx20             = ix2 - jx0;
 212             dy20             = iy2 - jy0;
 213             dz20             = iz2 - jz0;
 214             dx30             = ix3 - jx0;
 215             dy30             = iy3 - jy0;
 216             dz30             = iz3 - jz0;
 217
 218             /* Calculate squared distance and things based on it */
 219             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 220             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 221             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 222             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 223
 224             rinv00           = gmx_invsqrt(rsq00);
 225             rinv10           = gmx_invsqrt(rsq10);
 226             rinv20           = gmx_invsqrt(rsq20);
 227             rinv30           = gmx_invsqrt(rsq30);
 228
 229             rinvsq00         = rinv00*rinv00;
 230             rinvsq10         = rinv10*rinv10;
 231             rinvsq20         = rinv20*rinv20;
 232             rinvsq30         = rinv30*rinv30;
 233
 234             /* Load parameters for j particles */
 235             jq0              = charge[jnr+0];
 236             vdwjidx0         = 2*vdwtype[jnr+0];
 237
 238             /**************************
 239              * CALCULATE INTERACTIONS *
 240              **************************/
 241
 242             if (rsq00<rcutoff2)
 243             {
 244
 245             r00              = rsq00*rinv00;
 246
 247             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 248             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 249             c6grid_00        = vdwgridparam[vdwioffset0+vdwjidx0];
 250
 251             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 252             ewcljrsq         = ewclj2*rsq00;
 253             exponent         = exp(-ewcljrsq);
 254             poly             = exponent*(1.0 + ewcljrsq + ewcljrsq*ewcljrsq*0.5);
 255             vvdw6            = (c6_00-c6grid_00*(1.0-poly))*rinvsix;
 256             vvdw12           = c12_00*rinvsix*rinvsix;
 257             vvdw             = (vvdw12 - c12_00*sh_vdw_invrcut6*sh_vdw_invrcut6)*(1.0/12.0) - (vvdw6 - c6_00*sh_vdw_invrcut6 - c6grid_00*sh_lj_ewald)*(1.0/6.0);
 258             fvdw             = (vvdw12 - vvdw6 - c6grid_00*(1.0/6.0)*exponent*ewclj6)*rinvsq00;
 259
 260             /* Update potential sums from outer loop */
 261             vvdwsum         += vvdw;
 262
 263             fscal            = fvdw;
 264
 265             /* Calculate temporary vectorial force */
 266             tx               = fscal*dx00;
 267             ty               = fscal*dy00;
 268             tz               = fscal*dz00;
 269
 270             /* Update vectorial force */
 271             fix0            += tx;
 272             fiy0            += ty;
 273             fiz0            += tz;
 274             f[j_coord_offset+DIM*0+XX] -= tx;
 275             f[j_coord_offset+DIM*0+YY] -= ty;
 276             f[j_coord_offset+DIM*0+ZZ] -= tz;
 277
 278             }
 279
 280             /**************************
 281              * CALCULATE INTERACTIONS *
 282              **************************/
 283
 284             if (rsq10<rcutoff2)
 285             {
 286
 287             r10              = rsq10*rinv10;
 288
 289             qq10             = iq1*jq0;
 290
 291             /* EWALD ELECTROSTATICS */
 292
 293             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 294             ewrt             = r10*ewtabscale;
 295             ewitab           = ewrt;
 296             eweps            = ewrt-ewitab;
 297             ewitab           = 4*ewitab;
 298             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 299             velec            = qq10*((rinv10-sh_ewald)-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 300             felec            = qq10*rinv10*(rinvsq10-felec);
 301
 302             /* Update potential sums from outer loop */
 303             velecsum        += velec;
 304
 305             fscal            = felec;
 306
 307             /* Calculate temporary vectorial force */
 308             tx               = fscal*dx10;
 309             ty               = fscal*dy10;
 310             tz               = fscal*dz10;
 311
 312             /* Update vectorial force */
 313             fix1            += tx;
 314             fiy1            += ty;
 315             fiz1            += tz;
 316             f[j_coord_offset+DIM*0+XX] -= tx;
 317             f[j_coord_offset+DIM*0+YY] -= ty;
 318             f[j_coord_offset+DIM*0+ZZ] -= tz;
 319
 320             }
 321
 322             /**************************
 323              * CALCULATE INTERACTIONS *
 324              **************************/
 325
 326             if (rsq20<rcutoff2)
 327             {
 328
 329             r20              = rsq20*rinv20;
 330
 331             qq20             = iq2*jq0;
 332
 333             /* EWALD ELECTROSTATICS */
 334
 335             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 336             ewrt             = r20*ewtabscale;
 337             ewitab           = ewrt;
 338             eweps            = ewrt-ewitab;
 339             ewitab           = 4*ewitab;
 340             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 341             velec            = qq20*((rinv20-sh_ewald)-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 342             felec            = qq20*rinv20*(rinvsq20-felec);
 343
 344             /* Update potential sums from outer loop */
 345             velecsum        += velec;
 346
 347             fscal            = felec;
 348
 349             /* Calculate temporary vectorial force */
 350             tx               = fscal*dx20;
 351             ty               = fscal*dy20;
 352             tz               = fscal*dz20;
 353
 354             /* Update vectorial force */
 355             fix2            += tx;
 356             fiy2            += ty;
 357             fiz2            += tz;
 358             f[j_coord_offset+DIM*0+XX] -= tx;
 359             f[j_coord_offset+DIM*0+YY] -= ty;
 360             f[j_coord_offset+DIM*0+ZZ] -= tz;
 361
 362             }
 363
 364             /**************************
 365              * CALCULATE INTERACTIONS *
 366              **************************/
 367
 368             if (rsq30<rcutoff2)
 369             {
 370
 371             r30              = rsq30*rinv30;
 372
 373             qq30             = iq3*jq0;
 374
 375             /* EWALD ELECTROSTATICS */
 376
 377             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 378             ewrt             = r30*ewtabscale;
 379             ewitab           = ewrt;
 380             eweps            = ewrt-ewitab;
 381             ewitab           = 4*ewitab;
 382             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 383             velec            = qq30*((rinv30-sh_ewald)-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 384             felec            = qq30*rinv30*(rinvsq30-felec);
 385
 386             /* Update potential sums from outer loop */
 387             velecsum        += velec;
 388
 389             fscal            = felec;
 390
 391             /* Calculate temporary vectorial force */
 392             tx               = fscal*dx30;
 393             ty               = fscal*dy30;
 394             tz               = fscal*dz30;
 395
 396             /* Update vectorial force */
 397             fix3            += tx;
 398             fiy3            += ty;
 399             fiz3            += tz;
 400             f[j_coord_offset+DIM*0+XX] -= tx;
 401             f[j_coord_offset+DIM*0+YY] -= ty;
 402             f[j_coord_offset+DIM*0+ZZ] -= tz;
 403
 404             }
 405
 406             /* Inner loop uses 181 flops */
 407         }
 408         /* End of innermost loop */
 409
 410         tx = ty = tz = 0;
 411         f[i_coord_offset+DIM*0+XX] += fix0;
 412         f[i_coord_offset+DIM*0+YY] += fiy0;
 413         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 414         tx                         += fix0;
 415         ty                         += fiy0;
 416         tz                         += fiz0;
 417         f[i_coord_offset+DIM*1+XX] += fix1;
 418         f[i_coord_offset+DIM*1+YY] += fiy1;
 419         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 420         tx                         += fix1;
 421         ty                         += fiy1;
 422         tz                         += fiz1;
 423         f[i_coord_offset+DIM*2+XX] += fix2;
 424         f[i_coord_offset+DIM*2+YY] += fiy2;
 425         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 426         tx                         += fix2;
 427         ty                         += fiy2;
 428         tz                         += fiz2;
 429         f[i_coord_offset+DIM*3+XX] += fix3;
 430         f[i_coord_offset+DIM*3+YY] += fiy3;
 431         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 432         tx                         += fix3;
 433         ty                         += fiy3;
 434         tz                         += fiz3;
 435         fshift[i_shift_offset+XX]  += tx;
 436         fshift[i_shift_offset+YY]  += ty;
 437         fshift[i_shift_offset+ZZ]  += tz;
 438
 439         ggid                        = gid[iidx];
 440         /* Update potential energies */
 441         kernel_data->energygrp_elec[ggid] += velecsum;
 442         kernel_data->energygrp_vdw[ggid] += vvdwsum;
 443
 444         /* Increment number of inner iterations */
 445         inneriter                  += j_index_end - j_index_start;
 446
 447         /* Outer loop uses 41 flops */
 448     }
 449
 450     /* Increment number of outer iterations */
 451     outeriter        += nri;
 452
 453     /* Update outer/inner flops */
 454
 455     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_VF,outeriter*41 + inneriter*181);
 456 }
 457 /*
 458  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSh_VdwLJEwSh_GeomW4P1_F_c
 459  * Electrostatics interaction: Ewald
 460  * VdW interaction:            LJEwald
 461  * Geometry:                   Water4-Particle
 462  * Calculate force/pot:        Force
 463  */
 464 void
 465 nb_kernel_ElecEwSh_VdwLJEwSh_GeomW4P1_F_c
 466                     (t_nblist                    * gmx_restrict       nlist,
 467                      rvec                        * gmx_restrict          xx,
 468                      rvec                        * gmx_restrict          ff,
 469                      t_forcerec                  * gmx_restrict          fr,
 470                      t_mdatoms                   * gmx_restrict     mdatoms,
 471                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 472                      t_nrnb                      * gmx_restrict        nrnb)
 473 {
 474     int              i_shift_offset,i_coord_offset,j_coord_offset;
 475     int              j_index_start,j_index_end;
 476     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 477     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 478     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 479     real             *shiftvec,*fshift,*x,*f;
 480     int              vdwioffset0;
 481     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 482     int              vdwioffset1;
 483     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 484     int              vdwioffset2;
 485     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 486     int              vdwioffset3;
 487     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
 488     int              vdwjidx0;
 489     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 490     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
 491     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
 492     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
 493     real             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
 494     real             velec,felec,velecsum,facel,crf,krf,krf2;
 495     real             *charge;
 496     int              nvdwtype;
 497     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
 498     int              *vdwtype;
 499     real             *vdwparam;
 500     real             c6grid_00;
 501     real             c6grid_10;
 502     real             c6grid_20;
 503     real             c6grid_30;
 504     real             ewclj,ewclj2,ewclj6,ewcljrsq,poly,exponent,sh_lj_ewald;
 505     real             *vdwgridparam;
 506     int              ewitab;
 507     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
 508     real             *ewtab;
 509
 510     x                = xx[0];
 511     f                = ff[0];
 512
 513     nri              = nlist->nri;
 514     iinr             = nlist->iinr;
 515     jindex           = nlist->jindex;
 516     jjnr             = nlist->jjnr;
 517     shiftidx         = nlist->shift;
 518     gid              = nlist->gid;
 519     shiftvec         = fr->shift_vec[0];
 520     fshift           = fr->fshift[0];
 521     facel            = fr->epsfac;
 522     charge           = mdatoms->chargeA;
 523     nvdwtype         = fr->ntype;
 524     vdwparam         = fr->nbfp;
 525     vdwtype          = mdatoms->typeA;
 526     vdwgridparam     = fr->ljpme_c6grid;
 527     ewclj            = fr->ewaldcoeff_lj;
 528     sh_lj_ewald      = fr->ic->sh_lj_ewald;
 529     ewclj2           = ewclj*ewclj;
 530     ewclj6           = ewclj2*ewclj2*ewclj2;
 531
 532     sh_ewald         = fr->ic->sh_ewald;
 533     ewtab            = fr->ic->tabq_coul_F;
 534     ewtabscale       = fr->ic->tabq_scale;
 535     ewtabhalfspace   = 0.5/ewtabscale;
 536
 537     /* Setup water-specific parameters */
 538     inr              = nlist->iinr[0];
 539     iq1              = facel*charge[inr+1];
 540     iq2              = facel*charge[inr+2];
 541     iq3              = facel*charge[inr+3];
 542     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 543
 544     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 545     rcutoff          = fr->rcoulomb;
 546     rcutoff2         = rcutoff*rcutoff;
 547
 548     sh_vdw_invrcut6  = fr->ic->sh_invrc6;
 549     rvdw             = fr->rvdw;
 550
 551     outeriter        = 0;
 552     inneriter        = 0;
 553
 554     /* Start outer loop over neighborlists */
 555     for(iidx=0; iidx<nri; iidx++)
 556     {
 557         /* Load shift vector for this list */
 558         i_shift_offset   = DIM*shiftidx[iidx];
 559         shX              = shiftvec[i_shift_offset+XX];
 560         shY              = shiftvec[i_shift_offset+YY];
 561         shZ              = shiftvec[i_shift_offset+ZZ];
 562
 563         /* Load limits for loop over neighbors */
 564         j_index_start    = jindex[iidx];
 565         j_index_end      = jindex[iidx+1];
 566
 567         /* Get outer coordinate index */
 568         inr              = iinr[iidx];
 569         i_coord_offset   = DIM*inr;
 570
 571         /* Load i particle coords and add shift vector */
 572         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 573         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 574         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 575         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 576         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 577         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 578         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 579         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 580         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 581         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 582         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 583         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 584
 585         fix0             = 0.0;
 586         fiy0             = 0.0;
 587         fiz0             = 0.0;
 588         fix1             = 0.0;
 589         fiy1             = 0.0;
 590         fiz1             = 0.0;
 591         fix2             = 0.0;
 592         fiy2             = 0.0;
 593         fiz2             = 0.0;
 594         fix3             = 0.0;
 595         fiy3             = 0.0;
 596         fiz3             = 0.0;
 597
 598         /* Start inner kernel loop */
 599         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 600         {
 601             /* Get j neighbor index, and coordinate index */
 602             jnr              = jjnr[jidx];
 603             j_coord_offset   = DIM*jnr;
 604
 605             /* load j atom coordinates */
 606             jx0              = x[j_coord_offset+DIM*0+XX];
 607             jy0              = x[j_coord_offset+DIM*0+YY];
 608             jz0              = x[j_coord_offset+DIM*0+ZZ];
 609
 610             /* Calculate displacement vector */
 611             dx00             = ix0 - jx0;
 612             dy00             = iy0 - jy0;
 613             dz00             = iz0 - jz0;
 614             dx10             = ix1 - jx0;
 615             dy10             = iy1 - jy0;
 616             dz10             = iz1 - jz0;
 617             dx20             = ix2 - jx0;
 618             dy20             = iy2 - jy0;
 619             dz20             = iz2 - jz0;
 620             dx30             = ix3 - jx0;
 621             dy30             = iy3 - jy0;
 622             dz30             = iz3 - jz0;
 623
 624             /* Calculate squared distance and things based on it */
 625             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 626             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 627             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 628             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 629
 630             rinv00           = gmx_invsqrt(rsq00);
 631             rinv10           = gmx_invsqrt(rsq10);
 632             rinv20           = gmx_invsqrt(rsq20);
 633             rinv30           = gmx_invsqrt(rsq30);
 634
 635             rinvsq00         = rinv00*rinv00;
 636             rinvsq10         = rinv10*rinv10;
 637             rinvsq20         = rinv20*rinv20;
 638             rinvsq30         = rinv30*rinv30;
 639
 640             /* Load parameters for j particles */
 641             jq0              = charge[jnr+0];
 642             vdwjidx0         = 2*vdwtype[jnr+0];
 643
 644             /**************************
 645              * CALCULATE INTERACTIONS *
 646              **************************/
 647
 648             if (rsq00<rcutoff2)
 649             {
 650
 651             r00              = rsq00*rinv00;
 652
 653             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 654             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 655             c6grid_00        = vdwgridparam[vdwioffset0+vdwjidx0];
 656
 657             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 658             ewcljrsq         = ewclj2*rsq00;
 659             exponent         = exp(-ewcljrsq);
 660             poly             = exponent*(1.0 + ewcljrsq + ewcljrsq*ewcljrsq*0.5);
 661             fvdw             = (((c12_00*rinvsix - c6_00 + c6grid_00*(1.0-poly))*rinvsix) - c6grid_00*(1.0/6.0)*exponent*ewclj6)*rinvsq00;
 662
 663             fscal            = fvdw;
 664
 665             /* Calculate temporary vectorial force */
 666             tx               = fscal*dx00;
 667             ty               = fscal*dy00;
 668             tz               = fscal*dz00;
 669
 670             /* Update vectorial force */
 671             fix0            += tx;
 672             fiy0            += ty;
 673             fiz0            += tz;
 674             f[j_coord_offset+DIM*0+XX] -= tx;
 675             f[j_coord_offset+DIM*0+YY] -= ty;
 676             f[j_coord_offset+DIM*0+ZZ] -= tz;
 677
 678             }
 679
 680             /**************************
 681              * CALCULATE INTERACTIONS *
 682              **************************/
 683
 684             if (rsq10<rcutoff2)
 685             {
 686
 687             r10              = rsq10*rinv10;
 688
 689             qq10             = iq1*jq0;
 690
 691             /* EWALD ELECTROSTATICS */
 692
 693             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 694             ewrt             = r10*ewtabscale;
 695             ewitab           = ewrt;
 696             eweps            = ewrt-ewitab;
 697             felec            = (1.0-eweps)*ewtab[ewitab]+eweps*ewtab[ewitab+1];
 698             felec            = qq10*rinv10*(rinvsq10-felec);
 699
 700             fscal            = felec;
 701
 702             /* Calculate temporary vectorial force */
 703             tx               = fscal*dx10;
 704             ty               = fscal*dy10;
 705             tz               = fscal*dz10;
 706
 707             /* Update vectorial force */
 708             fix1            += tx;
 709             fiy1            += ty;
 710             fiz1            += tz;
 711             f[j_coord_offset+DIM*0+XX] -= tx;
 712             f[j_coord_offset+DIM*0+YY] -= ty;
 713             f[j_coord_offset+DIM*0+ZZ] -= tz;
 714
 715             }
 716
 717             /**************************
 718              * CALCULATE INTERACTIONS *
 719              **************************/
 720
 721             if (rsq20<rcutoff2)
 722             {
 723
 724             r20              = rsq20*rinv20;
 725
 726             qq20             = iq2*jq0;
 727
 728             /* EWALD ELECTROSTATICS */
 729
 730             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 731             ewrt             = r20*ewtabscale;
 732             ewitab           = ewrt;
 733             eweps            = ewrt-ewitab;
 734             felec            = (1.0-eweps)*ewtab[ewitab]+eweps*ewtab[ewitab+1];
 735             felec            = qq20*rinv20*(rinvsq20-felec);
 736
 737             fscal            = felec;
 738
 739             /* Calculate temporary vectorial force */
 740             tx               = fscal*dx20;
 741             ty               = fscal*dy20;
 742             tz               = fscal*dz20;
 743
 744             /* Update vectorial force */
 745             fix2            += tx;
 746             fiy2            += ty;
 747             fiz2            += tz;
 748             f[j_coord_offset+DIM*0+XX] -= tx;
 749             f[j_coord_offset+DIM*0+YY] -= ty;
 750             f[j_coord_offset+DIM*0+ZZ] -= tz;
 751
 752             }
 753
 754             /**************************
 755              * CALCULATE INTERACTIONS *
 756              **************************/
 757
 758             if (rsq30<rcutoff2)
 759             {
 760
 761             r30              = rsq30*rinv30;
 762
 763             qq30             = iq3*jq0;
 764
 765             /* EWALD ELECTROSTATICS */
 766
 767             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 768             ewrt             = r30*ewtabscale;
 769             ewitab           = ewrt;
 770             eweps            = ewrt-ewitab;
 771             felec            = (1.0-eweps)*ewtab[ewitab]+eweps*ewtab[ewitab+1];
 772             felec            = qq30*rinv30*(rinvsq30-felec);
 773
 774             fscal            = felec;
 775
 776             /* Calculate temporary vectorial force */
 777             tx               = fscal*dx30;
 778             ty               = fscal*dy30;
 779             tz               = fscal*dz30;
 780
 781             /* Update vectorial force */
 782             fix3            += tx;
 783             fiy3            += ty;
 784             fiz3            += tz;
 785             f[j_coord_offset+DIM*0+XX] -= tx;
 786             f[j_coord_offset+DIM*0+YY] -= ty;
 787             f[j_coord_offset+DIM*0+ZZ] -= tz;
 788
 789             }
 790
 791             /* Inner loop uses 146 flops */
 792         }
 793         /* End of innermost loop */
 794
 795         tx = ty = tz = 0;
 796         f[i_coord_offset+DIM*0+XX] += fix0;
 797         f[i_coord_offset+DIM*0+YY] += fiy0;
 798         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 799         tx                         += fix0;
 800         ty                         += fiy0;
 801         tz                         += fiz0;
 802         f[i_coord_offset+DIM*1+XX] += fix1;
 803         f[i_coord_offset+DIM*1+YY] += fiy1;
 804         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 805         tx                         += fix1;
 806         ty                         += fiy1;
 807         tz                         += fiz1;
 808         f[i_coord_offset+DIM*2+XX] += fix2;
 809         f[i_coord_offset+DIM*2+YY] += fiy2;
 810         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 811         tx                         += fix2;
 812         ty                         += fiy2;
 813         tz                         += fiz2;
 814         f[i_coord_offset+DIM*3+XX] += fix3;
 815         f[i_coord_offset+DIM*3+YY] += fiy3;
 816         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 817         tx                         += fix3;
 818         ty                         += fiy3;
 819         tz                         += fiz3;
 820         fshift[i_shift_offset+XX]  += tx;
 821         fshift[i_shift_offset+YY]  += ty;
 822         fshift[i_shift_offset+ZZ]  += tz;
 823
 824         /* Increment number of inner iterations */
 825         inneriter                  += j_index_end - j_index_start;
 826
 827         /* Outer loop uses 39 flops */
 828     }
 829
 830     /* Increment number of outer iterations */
 831     outeriter        += nri;
 832
 833     /* Update outer/inner flops */
 834
 835     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_F,outeriter*39 + inneriter*146);
 836 }