src/gromacs/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecRFCut_VdwLJSh_GeomW4P1_c.c

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2012,2013,2014, by the GROMACS development team, led by
   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
   6  * and including many others, as listed in the AUTHORS file in the
   7  * top-level source directory and at http://www.gromacs.org.
   8  *
   9  * GROMACS is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1
  12  * of the License, or (at your option) any later version.
  13  *
  14  * GROMACS is distributed in the hope that it will be useful,
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  34  */
  35 /*
  36  * Note: this file was generated by the GROMACS c kernel generator.
  37  */
  38 #include "config.h"
  39
  40 #include <math.h>
  41
  42 #include "../nb_kernel.h"
  43 #include "gromacs/legacyheaders/types/simple.h"
  44 #include "gromacs/math/vec.h"
  45 #include "gromacs/legacyheaders/nrnb.h"
  46
  47 /*
  48  * Gromacs nonbonded kernel:   nb_kernel_ElecRFCut_VdwLJSh_GeomW4P1_VF_c
  49  * Electrostatics interaction: ReactionField
  50  * VdW interaction:            LennardJones
  51  * Geometry:                   Water4-Particle
  52  * Calculate force/pot:        PotentialAndForce
  53  */
  54 void
  55 nb_kernel_ElecRFCut_VdwLJSh_GeomW4P1_VF_c
  56                     (t_nblist                    * gmx_restrict       nlist,
  57                      rvec                        * gmx_restrict          xx,
  58                      rvec                        * gmx_restrict          ff,
  59                      t_forcerec                  * gmx_restrict          fr,
  60                      t_mdatoms                   * gmx_restrict     mdatoms,
  61                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
  62                      t_nrnb                      * gmx_restrict        nrnb)
  63 {
  64     int              i_shift_offset,i_coord_offset,j_coord_offset;
  65     int              j_index_start,j_index_end;
  66     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
  67     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
  68     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  69     real             *shiftvec,*fshift,*x,*f;
  70     int              vdwioffset0;
  71     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  72     int              vdwioffset1;
  73     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
  74     int              vdwioffset2;
  75     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
  76     int              vdwioffset3;
  77     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
  78     int              vdwjidx0;
  79     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  80     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
  81     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
  82     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
  83     real             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
  84     real             velec,felec,velecsum,facel,crf,krf,krf2;
  85     real             *charge;
  86     int              nvdwtype;
  87     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
  88     int              *vdwtype;
  89     real             *vdwparam;
  90
  91     x                = xx[0];
  92     f                = ff[0];
  93
  94     nri              = nlist->nri;
  95     iinr             = nlist->iinr;
  96     jindex           = nlist->jindex;
  97     jjnr             = nlist->jjnr;
  98     shiftidx         = nlist->shift;
  99     gid              = nlist->gid;
 100     shiftvec         = fr->shift_vec[0];
 101     fshift           = fr->fshift[0];
 102     facel            = fr->epsfac;
 103     charge           = mdatoms->chargeA;
 104     krf              = fr->ic->k_rf;
 105     krf2             = krf*2.0;
 106     crf              = fr->ic->c_rf;
 107     nvdwtype         = fr->ntype;
 108     vdwparam         = fr->nbfp;
 109     vdwtype          = mdatoms->typeA;
 110
 111     /* Setup water-specific parameters */
 112     inr              = nlist->iinr[0];
 113     iq1              = facel*charge[inr+1];
 114     iq2              = facel*charge[inr+2];
 115     iq3              = facel*charge[inr+3];
 116     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 117
 118     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 119     rcutoff          = fr->rcoulomb;
 120     rcutoff2         = rcutoff*rcutoff;
 121
 122     sh_vdw_invrcut6  = fr->ic->sh_invrc6;
 123     rvdw             = fr->rvdw;
 124
 125     outeriter        = 0;
 126     inneriter        = 0;
 127
 128     /* Start outer loop over neighborlists */
 129     for(iidx=0; iidx<nri; iidx++)
 130     {
 131         /* Load shift vector for this list */
 132         i_shift_offset   = DIM*shiftidx[iidx];
 133         shX              = shiftvec[i_shift_offset+XX];
 134         shY              = shiftvec[i_shift_offset+YY];
 135         shZ              = shiftvec[i_shift_offset+ZZ];
 136
 137         /* Load limits for loop over neighbors */
 138         j_index_start    = jindex[iidx];
 139         j_index_end      = jindex[iidx+1];
 140
 141         /* Get outer coordinate index */
 142         inr              = iinr[iidx];
 143         i_coord_offset   = DIM*inr;
 144
 145         /* Load i particle coords and add shift vector */
 146         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 147         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 148         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 149         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 150         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 151         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 152         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 153         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 154         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 155         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 156         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 157         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 158
 159         fix0             = 0.0;
 160         fiy0             = 0.0;
 161         fiz0             = 0.0;
 162         fix1             = 0.0;
 163         fiy1             = 0.0;
 164         fiz1             = 0.0;
 165         fix2             = 0.0;
 166         fiy2             = 0.0;
 167         fiz2             = 0.0;
 168         fix3             = 0.0;
 169         fiy3             = 0.0;
 170         fiz3             = 0.0;
 171
 172         /* Reset potential sums */
 173         velecsum         = 0.0;
 174         vvdwsum          = 0.0;
 175
 176         /* Start inner kernel loop */
 177         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 178         {
 179             /* Get j neighbor index, and coordinate index */
 180             jnr              = jjnr[jidx];
 181             j_coord_offset   = DIM*jnr;
 182
 183             /* load j atom coordinates */
 184             jx0              = x[j_coord_offset+DIM*0+XX];
 185             jy0              = x[j_coord_offset+DIM*0+YY];
 186             jz0              = x[j_coord_offset+DIM*0+ZZ];
 187
 188             /* Calculate displacement vector */
 189             dx00             = ix0 - jx0;
 190             dy00             = iy0 - jy0;
 191             dz00             = iz0 - jz0;
 192             dx10             = ix1 - jx0;
 193             dy10             = iy1 - jy0;
 194             dz10             = iz1 - jz0;
 195             dx20             = ix2 - jx0;
 196             dy20             = iy2 - jy0;
 197             dz20             = iz2 - jz0;
 198             dx30             = ix3 - jx0;
 199             dy30             = iy3 - jy0;
 200             dz30             = iz3 - jz0;
 201
 202             /* Calculate squared distance and things based on it */
 203             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 204             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 205             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 206             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 207
 208             rinv10           = gmx_invsqrt(rsq10);
 209             rinv20           = gmx_invsqrt(rsq20);
 210             rinv30           = gmx_invsqrt(rsq30);
 211
 212             rinvsq00         = 1.0/rsq00;
 213             rinvsq10         = rinv10*rinv10;
 214             rinvsq20         = rinv20*rinv20;
 215             rinvsq30         = rinv30*rinv30;
 216
 217             /* Load parameters for j particles */
 218             jq0              = charge[jnr+0];
 219             vdwjidx0         = 2*vdwtype[jnr+0];
 220
 221             /**************************
 222              * CALCULATE INTERACTIONS *
 223              **************************/
 224
 225             if (rsq00<rcutoff2)
 226             {
 227
 228             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 229             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 230
 231             /* LENNARD-JONES DISPERSION/REPULSION */
 232
 233             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 234             vvdw6            = c6_00*rinvsix;
 235             vvdw12           = c12_00*rinvsix*rinvsix;
 236             vvdw             = (vvdw12 - c12_00*sh_vdw_invrcut6*sh_vdw_invrcut6)*(1.0/12.0) - (vvdw6 - c6_00*sh_vdw_invrcut6)*(1.0/6.0);
 237             fvdw             = (vvdw12-vvdw6)*rinvsq00;
 238
 239             /* Update potential sums from outer loop */
 240             vvdwsum         += vvdw;
 241
 242             fscal            = fvdw;
 243
 244             /* Calculate temporary vectorial force */
 245             tx               = fscal*dx00;
 246             ty               = fscal*dy00;
 247             tz               = fscal*dz00;
 248
 249             /* Update vectorial force */
 250             fix0            += tx;
 251             fiy0            += ty;
 252             fiz0            += tz;
 253             f[j_coord_offset+DIM*0+XX] -= tx;
 254             f[j_coord_offset+DIM*0+YY] -= ty;
 255             f[j_coord_offset+DIM*0+ZZ] -= tz;
 256
 257             }
 258
 259             /**************************
 260              * CALCULATE INTERACTIONS *
 261              **************************/
 262
 263             if (rsq10<rcutoff2)
 264             {
 265
 266             qq10             = iq1*jq0;
 267
 268             /* REACTION-FIELD ELECTROSTATICS */
 269             velec            = qq10*(rinv10+krf*rsq10-crf);
 270             felec            = qq10*(rinv10*rinvsq10-krf2);
 271
 272             /* Update potential sums from outer loop */
 273             velecsum        += velec;
 274
 275             fscal            = felec;
 276
 277             /* Calculate temporary vectorial force */
 278             tx               = fscal*dx10;
 279             ty               = fscal*dy10;
 280             tz               = fscal*dz10;
 281
 282             /* Update vectorial force */
 283             fix1            += tx;
 284             fiy1            += ty;
 285             fiz1            += tz;
 286             f[j_coord_offset+DIM*0+XX] -= tx;
 287             f[j_coord_offset+DIM*0+YY] -= ty;
 288             f[j_coord_offset+DIM*0+ZZ] -= tz;
 289
 290             }
 291
 292             /**************************
 293              * CALCULATE INTERACTIONS *
 294              **************************/
 295
 296             if (rsq20<rcutoff2)
 297             {
 298
 299             qq20             = iq2*jq0;
 300
 301             /* REACTION-FIELD ELECTROSTATICS */
 302             velec            = qq20*(rinv20+krf*rsq20-crf);
 303             felec            = qq20*(rinv20*rinvsq20-krf2);
 304
 305             /* Update potential sums from outer loop */
 306             velecsum        += velec;
 307
 308             fscal            = felec;
 309
 310             /* Calculate temporary vectorial force */
 311             tx               = fscal*dx20;
 312             ty               = fscal*dy20;
 313             tz               = fscal*dz20;
 314
 315             /* Update vectorial force */
 316             fix2            += tx;
 317             fiy2            += ty;
 318             fiz2            += tz;
 319             f[j_coord_offset+DIM*0+XX] -= tx;
 320             f[j_coord_offset+DIM*0+YY] -= ty;
 321             f[j_coord_offset+DIM*0+ZZ] -= tz;
 322
 323             }
 324
 325             /**************************
 326              * CALCULATE INTERACTIONS *
 327              **************************/
 328
 329             if (rsq30<rcutoff2)
 330             {
 331
 332             qq30             = iq3*jq0;
 333
 334             /* REACTION-FIELD ELECTROSTATICS */
 335             velec            = qq30*(rinv30+krf*rsq30-crf);
 336             felec            = qq30*(rinv30*rinvsq30-krf2);
 337
 338             /* Update potential sums from outer loop */
 339             velecsum        += velec;
 340
 341             fscal            = felec;
 342
 343             /* Calculate temporary vectorial force */
 344             tx               = fscal*dx30;
 345             ty               = fscal*dy30;
 346             tz               = fscal*dz30;
 347
 348             /* Update vectorial force */
 349             fix3            += tx;
 350             fiy3            += ty;
 351             fiz3            += tz;
 352             f[j_coord_offset+DIM*0+XX] -= tx;
 353             f[j_coord_offset+DIM*0+YY] -= ty;
 354             f[j_coord_offset+DIM*0+ZZ] -= tz;
 355
 356             }
 357
 358             /* Inner loop uses 133 flops */
 359         }
 360         /* End of innermost loop */
 361
 362         tx = ty = tz = 0;
 363         f[i_coord_offset+DIM*0+XX] += fix0;
 364         f[i_coord_offset+DIM*0+YY] += fiy0;
 365         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 366         tx                         += fix0;
 367         ty                         += fiy0;
 368         tz                         += fiz0;
 369         f[i_coord_offset+DIM*1+XX] += fix1;
 370         f[i_coord_offset+DIM*1+YY] += fiy1;
 371         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 372         tx                         += fix1;
 373         ty                         += fiy1;
 374         tz                         += fiz1;
 375         f[i_coord_offset+DIM*2+XX] += fix2;
 376         f[i_coord_offset+DIM*2+YY] += fiy2;
 377         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 378         tx                         += fix2;
 379         ty                         += fiy2;
 380         tz                         += fiz2;
 381         f[i_coord_offset+DIM*3+XX] += fix3;
 382         f[i_coord_offset+DIM*3+YY] += fiy3;
 383         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 384         tx                         += fix3;
 385         ty                         += fiy3;
 386         tz                         += fiz3;
 387         fshift[i_shift_offset+XX]  += tx;
 388         fshift[i_shift_offset+YY]  += ty;
 389         fshift[i_shift_offset+ZZ]  += tz;
 390
 391         ggid                        = gid[iidx];
 392         /* Update potential energies */
 393         kernel_data->energygrp_elec[ggid] += velecsum;
 394         kernel_data->energygrp_vdw[ggid] += vvdwsum;
 395
 396         /* Increment number of inner iterations */
 397         inneriter                  += j_index_end - j_index_start;
 398
 399         /* Outer loop uses 41 flops */
 400     }
 401
 402     /* Increment number of outer iterations */
 403     outeriter        += nri;
 404
 405     /* Update outer/inner flops */
 406
 407     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_VF,outeriter*41 + inneriter*133);
 408 }
 409 /*
 410  * Gromacs nonbonded kernel:   nb_kernel_ElecRFCut_VdwLJSh_GeomW4P1_F_c
 411  * Electrostatics interaction: ReactionField
 412  * VdW interaction:            LennardJones
 413  * Geometry:                   Water4-Particle
 414  * Calculate force/pot:        Force
 415  */
 416 void
 417 nb_kernel_ElecRFCut_VdwLJSh_GeomW4P1_F_c
 418                     (t_nblist                    * gmx_restrict       nlist,
 419                      rvec                        * gmx_restrict          xx,
 420                      rvec                        * gmx_restrict          ff,
 421                      t_forcerec                  * gmx_restrict          fr,
 422                      t_mdatoms                   * gmx_restrict     mdatoms,
 423                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 424                      t_nrnb                      * gmx_restrict        nrnb)
 425 {
 426     int              i_shift_offset,i_coord_offset,j_coord_offset;
 427     int              j_index_start,j_index_end;
 428     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 429     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 430     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 431     real             *shiftvec,*fshift,*x,*f;
 432     int              vdwioffset0;
 433     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 434     int              vdwioffset1;
 435     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 436     int              vdwioffset2;
 437     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 438     int              vdwioffset3;
 439     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
 440     int              vdwjidx0;
 441     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 442     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
 443     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
 444     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
 445     real             dx30,dy30,dz30,rsq30,rinv30,rinvsq30,r30,qq30,c6_30,c12_30,cexp1_30,cexp2_30;
 446     real             velec,felec,velecsum,facel,crf,krf,krf2;
 447     real             *charge;
 448     int              nvdwtype;
 449     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
 450     int              *vdwtype;
 451     real             *vdwparam;
 452
 453     x                = xx[0];
 454     f                = ff[0];
 455
 456     nri              = nlist->nri;
 457     iinr             = nlist->iinr;
 458     jindex           = nlist->jindex;
 459     jjnr             = nlist->jjnr;
 460     shiftidx         = nlist->shift;
 461     gid              = nlist->gid;
 462     shiftvec         = fr->shift_vec[0];
 463     fshift           = fr->fshift[0];
 464     facel            = fr->epsfac;
 465     charge           = mdatoms->chargeA;
 466     krf              = fr->ic->k_rf;
 467     krf2             = krf*2.0;
 468     crf              = fr->ic->c_rf;
 469     nvdwtype         = fr->ntype;
 470     vdwparam         = fr->nbfp;
 471     vdwtype          = mdatoms->typeA;
 472
 473     /* Setup water-specific parameters */
 474     inr              = nlist->iinr[0];
 475     iq1              = facel*charge[inr+1];
 476     iq2              = facel*charge[inr+2];
 477     iq3              = facel*charge[inr+3];
 478     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 479
 480     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 481     rcutoff          = fr->rcoulomb;
 482     rcutoff2         = rcutoff*rcutoff;
 483
 484     sh_vdw_invrcut6  = fr->ic->sh_invrc6;
 485     rvdw             = fr->rvdw;
 486
 487     outeriter        = 0;
 488     inneriter        = 0;
 489
 490     /* Start outer loop over neighborlists */
 491     for(iidx=0; iidx<nri; iidx++)
 492     {
 493         /* Load shift vector for this list */
 494         i_shift_offset   = DIM*shiftidx[iidx];
 495         shX              = shiftvec[i_shift_offset+XX];
 496         shY              = shiftvec[i_shift_offset+YY];
 497         shZ              = shiftvec[i_shift_offset+ZZ];
 498
 499         /* Load limits for loop over neighbors */
 500         j_index_start    = jindex[iidx];
 501         j_index_end      = jindex[iidx+1];
 502
 503         /* Get outer coordinate index */
 504         inr              = iinr[iidx];
 505         i_coord_offset   = DIM*inr;
 506
 507         /* Load i particle coords and add shift vector */
 508         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 509         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 510         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 511         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 512         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 513         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 514         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 515         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 516         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 517         ix3              = shX + x[i_coord_offset+DIM*3+XX];
 518         iy3              = shY + x[i_coord_offset+DIM*3+YY];
 519         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
 520
 521         fix0             = 0.0;
 522         fiy0             = 0.0;
 523         fiz0             = 0.0;
 524         fix1             = 0.0;
 525         fiy1             = 0.0;
 526         fiz1             = 0.0;
 527         fix2             = 0.0;
 528         fiy2             = 0.0;
 529         fiz2             = 0.0;
 530         fix3             = 0.0;
 531         fiy3             = 0.0;
 532         fiz3             = 0.0;
 533
 534         /* Start inner kernel loop */
 535         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 536         {
 537             /* Get j neighbor index, and coordinate index */
 538             jnr              = jjnr[jidx];
 539             j_coord_offset   = DIM*jnr;
 540
 541             /* load j atom coordinates */
 542             jx0              = x[j_coord_offset+DIM*0+XX];
 543             jy0              = x[j_coord_offset+DIM*0+YY];
 544             jz0              = x[j_coord_offset+DIM*0+ZZ];
 545
 546             /* Calculate displacement vector */
 547             dx00             = ix0 - jx0;
 548             dy00             = iy0 - jy0;
 549             dz00             = iz0 - jz0;
 550             dx10             = ix1 - jx0;
 551             dy10             = iy1 - jy0;
 552             dz10             = iz1 - jz0;
 553             dx20             = ix2 - jx0;
 554             dy20             = iy2 - jy0;
 555             dz20             = iz2 - jz0;
 556             dx30             = ix3 - jx0;
 557             dy30             = iy3 - jy0;
 558             dz30             = iz3 - jz0;
 559
 560             /* Calculate squared distance and things based on it */
 561             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 562             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 563             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 564             rsq30            = dx30*dx30+dy30*dy30+dz30*dz30;
 565
 566             rinv10           = gmx_invsqrt(rsq10);
 567             rinv20           = gmx_invsqrt(rsq20);
 568             rinv30           = gmx_invsqrt(rsq30);
 569
 570             rinvsq00         = 1.0/rsq00;
 571             rinvsq10         = rinv10*rinv10;
 572             rinvsq20         = rinv20*rinv20;
 573             rinvsq30         = rinv30*rinv30;
 574
 575             /* Load parameters for j particles */
 576             jq0              = charge[jnr+0];
 577             vdwjidx0         = 2*vdwtype[jnr+0];
 578
 579             /**************************
 580              * CALCULATE INTERACTIONS *
 581              **************************/
 582
 583             if (rsq00<rcutoff2)
 584             {
 585
 586             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 587             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 588
 589             /* LENNARD-JONES DISPERSION/REPULSION */
 590
 591             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 592             fvdw             = (c12_00*rinvsix-c6_00)*rinvsix*rinvsq00;
 593
 594             fscal            = fvdw;
 595
 596             /* Calculate temporary vectorial force */
 597             tx               = fscal*dx00;
 598             ty               = fscal*dy00;
 599             tz               = fscal*dz00;
 600
 601             /* Update vectorial force */
 602             fix0            += tx;
 603             fiy0            += ty;
 604             fiz0            += tz;
 605             f[j_coord_offset+DIM*0+XX] -= tx;
 606             f[j_coord_offset+DIM*0+YY] -= ty;
 607             f[j_coord_offset+DIM*0+ZZ] -= tz;
 608
 609             }
 610
 611             /**************************
 612              * CALCULATE INTERACTIONS *
 613              **************************/
 614
 615             if (rsq10<rcutoff2)
 616             {
 617
 618             qq10             = iq1*jq0;
 619
 620             /* REACTION-FIELD ELECTROSTATICS */
 621             felec            = qq10*(rinv10*rinvsq10-krf2);
 622
 623             fscal            = felec;
 624
 625             /* Calculate temporary vectorial force */
 626             tx               = fscal*dx10;
 627             ty               = fscal*dy10;
 628             tz               = fscal*dz10;
 629
 630             /* Update vectorial force */
 631             fix1            += tx;
 632             fiy1            += ty;
 633             fiz1            += tz;
 634             f[j_coord_offset+DIM*0+XX] -= tx;
 635             f[j_coord_offset+DIM*0+YY] -= ty;
 636             f[j_coord_offset+DIM*0+ZZ] -= tz;
 637
 638             }
 639
 640             /**************************
 641              * CALCULATE INTERACTIONS *
 642              **************************/
 643
 644             if (rsq20<rcutoff2)
 645             {
 646
 647             qq20             = iq2*jq0;
 648
 649             /* REACTION-FIELD ELECTROSTATICS */
 650             felec            = qq20*(rinv20*rinvsq20-krf2);
 651
 652             fscal            = felec;
 653
 654             /* Calculate temporary vectorial force */
 655             tx               = fscal*dx20;
 656             ty               = fscal*dy20;
 657             tz               = fscal*dz20;
 658
 659             /* Update vectorial force */
 660             fix2            += tx;
 661             fiy2            += ty;
 662             fiz2            += tz;
 663             f[j_coord_offset+DIM*0+XX] -= tx;
 664             f[j_coord_offset+DIM*0+YY] -= ty;
 665             f[j_coord_offset+DIM*0+ZZ] -= tz;
 666
 667             }
 668
 669             /**************************
 670              * CALCULATE INTERACTIONS *
 671              **************************/
 672
 673             if (rsq30<rcutoff2)
 674             {
 675
 676             qq30             = iq3*jq0;
 677
 678             /* REACTION-FIELD ELECTROSTATICS */
 679             felec            = qq30*(rinv30*rinvsq30-krf2);
 680
 681             fscal            = felec;
 682
 683             /* Calculate temporary vectorial force */
 684             tx               = fscal*dx30;
 685             ty               = fscal*dy30;
 686             tz               = fscal*dz30;
 687
 688             /* Update vectorial force */
 689             fix3            += tx;
 690             fiy3            += ty;
 691             fiz3            += tz;
 692             f[j_coord_offset+DIM*0+XX] -= tx;
 693             f[j_coord_offset+DIM*0+YY] -= ty;
 694             f[j_coord_offset+DIM*0+ZZ] -= tz;
 695
 696             }
 697
 698             /* Inner loop uses 108 flops */
 699         }
 700         /* End of innermost loop */
 701
 702         tx = ty = tz = 0;
 703         f[i_coord_offset+DIM*0+XX] += fix0;
 704         f[i_coord_offset+DIM*0+YY] += fiy0;
 705         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 706         tx                         += fix0;
 707         ty                         += fiy0;
 708         tz                         += fiz0;
 709         f[i_coord_offset+DIM*1+XX] += fix1;
 710         f[i_coord_offset+DIM*1+YY] += fiy1;
 711         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 712         tx                         += fix1;
 713         ty                         += fiy1;
 714         tz                         += fiz1;
 715         f[i_coord_offset+DIM*2+XX] += fix2;
 716         f[i_coord_offset+DIM*2+YY] += fiy2;
 717         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 718         tx                         += fix2;
 719         ty                         += fiy2;
 720         tz                         += fiz2;
 721         f[i_coord_offset+DIM*3+XX] += fix3;
 722         f[i_coord_offset+DIM*3+YY] += fiy3;
 723         f[i_coord_offset+DIM*3+ZZ] += fiz3;
 724         tx                         += fix3;
 725         ty                         += fiy3;
 726         tz                         += fiz3;
 727         fshift[i_shift_offset+XX]  += tx;
 728         fshift[i_shift_offset+YY]  += ty;
 729         fshift[i_shift_offset+ZZ]  += tz;
 730
 731         /* Increment number of inner iterations */
 732         inneriter                  += j_index_end - j_index_start;
 733
 734         /* Outer loop uses 39 flops */
 735     }
 736
 737     /* Increment number of outer iterations */
 738     outeriter        += nri;
 739
 740     /* Update outer/inner flops */
 741
 742     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4_F,outeriter*39 + inneriter*108);
 743 }