src/gromacs/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecEwSw_VdwLJSw_GeomW3P1_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 "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_ElecEwSw_VdwLJSw_GeomW3P1_VF_c
  49  * Electrostatics interaction: Ewald
  50  * VdW interaction:            LennardJones
  51  * Geometry:                   Water3-Particle
  52  * Calculate force/pot:        PotentialAndForce
  53  */
  54 void
  55 nb_kernel_ElecEwSw_VdwLJSw_GeomW3P1_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              vdwjidx0;
  77     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  78     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
  79     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
  80     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
  81     real             velec,felec,velecsum,facel,crf,krf,krf2;
  82     real             *charge;
  83     int              nvdwtype;
  84     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
  85     int              *vdwtype;
  86     real             *vdwparam;
  87     int              ewitab;
  88     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
  89     real             *ewtab;
  90     real             rswitch,swV3,swV4,swV5,swF2,swF3,swF4,d,d2,sw,dsw;
  91
  92     x                = xx[0];
  93     f                = ff[0];
  94
  95     nri              = nlist->nri;
  96     iinr             = nlist->iinr;
  97     jindex           = nlist->jindex;
  98     jjnr             = nlist->jjnr;
  99     shiftidx         = nlist->shift;
 100     gid              = nlist->gid;
 101     shiftvec         = fr->shift_vec[0];
 102     fshift           = fr->fshift[0];
 103     facel            = fr->epsfac;
 104     charge           = mdatoms->chargeA;
 105     nvdwtype         = fr->ntype;
 106     vdwparam         = fr->nbfp;
 107     vdwtype          = mdatoms->typeA;
 108
 109     sh_ewald         = fr->ic->sh_ewald;
 110     ewtab            = fr->ic->tabq_coul_FDV0;
 111     ewtabscale       = fr->ic->tabq_scale;
 112     ewtabhalfspace   = 0.5/ewtabscale;
 113
 114     /* Setup water-specific parameters */
 115     inr              = nlist->iinr[0];
 116     iq0              = facel*charge[inr+0];
 117     iq1              = facel*charge[inr+1];
 118     iq2              = facel*charge[inr+2];
 119     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 120
 121     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 122     rcutoff          = fr->rcoulomb;
 123     rcutoff2         = rcutoff*rcutoff;
 124
 125     rswitch          = fr->rcoulomb_switch;
 126     /* Setup switch parameters */
 127     d                = rcutoff-rswitch;
 128     swV3             = -10.0/(d*d*d);
 129     swV4             =  15.0/(d*d*d*d);
 130     swV5             =  -6.0/(d*d*d*d*d);
 131     swF2             = -30.0/(d*d*d);
 132     swF3             =  60.0/(d*d*d*d);
 133     swF4             = -30.0/(d*d*d*d*d);
 134
 135     outeriter        = 0;
 136     inneriter        = 0;
 137
 138     /* Start outer loop over neighborlists */
 139     for(iidx=0; iidx<nri; iidx++)
 140     {
 141         /* Load shift vector for this list */
 142         i_shift_offset   = DIM*shiftidx[iidx];
 143         shX              = shiftvec[i_shift_offset+XX];
 144         shY              = shiftvec[i_shift_offset+YY];
 145         shZ              = shiftvec[i_shift_offset+ZZ];
 146
 147         /* Load limits for loop over neighbors */
 148         j_index_start    = jindex[iidx];
 149         j_index_end      = jindex[iidx+1];
 150
 151         /* Get outer coordinate index */
 152         inr              = iinr[iidx];
 153         i_coord_offset   = DIM*inr;
 154
 155         /* Load i particle coords and add shift vector */
 156         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 157         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 158         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 159         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 160         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 161         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 162         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 163         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 164         iz2              = shZ + x[i_coord_offset+DIM*2+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
 176         /* Reset potential sums */
 177         velecsum         = 0.0;
 178         vvdwsum          = 0.0;
 179
 180         /* Start inner kernel loop */
 181         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 182         {
 183             /* Get j neighbor index, and coordinate index */
 184             jnr              = jjnr[jidx];
 185             j_coord_offset   = DIM*jnr;
 186
 187             /* load j atom coordinates */
 188             jx0              = x[j_coord_offset+DIM*0+XX];
 189             jy0              = x[j_coord_offset+DIM*0+YY];
 190             jz0              = x[j_coord_offset+DIM*0+ZZ];
 191
 192             /* Calculate displacement vector */
 193             dx00             = ix0 - jx0;
 194             dy00             = iy0 - jy0;
 195             dz00             = iz0 - jz0;
 196             dx10             = ix1 - jx0;
 197             dy10             = iy1 - jy0;
 198             dz10             = iz1 - jz0;
 199             dx20             = ix2 - jx0;
 200             dy20             = iy2 - jy0;
 201             dz20             = iz2 - jz0;
 202
 203             /* Calculate squared distance and things based on it */
 204             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 205             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 206             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 207
 208             rinv00           = gmx_invsqrt(rsq00);
 209             rinv10           = gmx_invsqrt(rsq10);
 210             rinv20           = gmx_invsqrt(rsq20);
 211
 212             rinvsq00         = rinv00*rinv00;
 213             rinvsq10         = rinv10*rinv10;
 214             rinvsq20         = rinv20*rinv20;
 215
 216             /* Load parameters for j particles */
 217             jq0              = charge[jnr+0];
 218             vdwjidx0         = 2*vdwtype[jnr+0];
 219
 220             /**************************
 221              * CALCULATE INTERACTIONS *
 222              **************************/
 223
 224             if (rsq00<rcutoff2)
 225             {
 226
 227             r00              = rsq00*rinv00;
 228
 229             qq00             = iq0*jq0;
 230             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 231             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 232
 233             /* EWALD ELECTROSTATICS */
 234
 235             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 236             ewrt             = r00*ewtabscale;
 237             ewitab           = ewrt;
 238             eweps            = ewrt-ewitab;
 239             ewitab           = 4*ewitab;
 240             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 241             velec            = qq00*(rinv00-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 242             felec            = qq00*rinv00*(rinvsq00-felec);
 243
 244             /* LENNARD-JONES DISPERSION/REPULSION */
 245
 246             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 247             vvdw6            = c6_00*rinvsix;
 248             vvdw12           = c12_00*rinvsix*rinvsix;
 249             vvdw             = vvdw12*(1.0/12.0) - vvdw6*(1.0/6.0);
 250             fvdw             = (vvdw12-vvdw6)*rinvsq00;
 251
 252             d                = r00-rswitch;
 253             d                = (d>0.0) ? d : 0.0;
 254             d2               = d*d;
 255             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
 256
 257             dsw              = d2*(swF2+d*(swF3+d*swF4));
 258
 259             /* Evaluate switch function */
 260             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
 261             felec            = felec*sw - rinv00*velec*dsw;
 262             fvdw             = fvdw*sw - rinv00*vvdw*dsw;
 263             velec           *= sw;
 264             vvdw            *= sw;
 265
 266             /* Update potential sums from outer loop */
 267             velecsum        += velec;
 268             vvdwsum         += vvdw;
 269
 270             fscal            = felec+fvdw;
 271
 272             /* Calculate temporary vectorial force */
 273             tx               = fscal*dx00;
 274             ty               = fscal*dy00;
 275             tz               = fscal*dz00;
 276
 277             /* Update vectorial force */
 278             fix0            += tx;
 279             fiy0            += ty;
 280             fiz0            += tz;
 281             f[j_coord_offset+DIM*0+XX] -= tx;
 282             f[j_coord_offset+DIM*0+YY] -= ty;
 283             f[j_coord_offset+DIM*0+ZZ] -= tz;
 284
 285             }
 286
 287             /**************************
 288              * CALCULATE INTERACTIONS *
 289              **************************/
 290
 291             if (rsq10<rcutoff2)
 292             {
 293
 294             r10              = rsq10*rinv10;
 295
 296             qq10             = iq1*jq0;
 297
 298             /* EWALD ELECTROSTATICS */
 299
 300             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 301             ewrt             = r10*ewtabscale;
 302             ewitab           = ewrt;
 303             eweps            = ewrt-ewitab;
 304             ewitab           = 4*ewitab;
 305             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 306             velec            = qq10*(rinv10-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 307             felec            = qq10*rinv10*(rinvsq10-felec);
 308
 309             d                = r10-rswitch;
 310             d                = (d>0.0) ? d : 0.0;
 311             d2               = d*d;
 312             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
 313
 314             dsw              = d2*(swF2+d*(swF3+d*swF4));
 315
 316             /* Evaluate switch function */
 317             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
 318             felec            = felec*sw - rinv10*velec*dsw;
 319             velec           *= sw;
 320
 321             /* Update potential sums from outer loop */
 322             velecsum        += velec;
 323
 324             fscal            = felec;
 325
 326             /* Calculate temporary vectorial force */
 327             tx               = fscal*dx10;
 328             ty               = fscal*dy10;
 329             tz               = fscal*dz10;
 330
 331             /* Update vectorial force */
 332             fix1            += tx;
 333             fiy1            += ty;
 334             fiz1            += tz;
 335             f[j_coord_offset+DIM*0+XX] -= tx;
 336             f[j_coord_offset+DIM*0+YY] -= ty;
 337             f[j_coord_offset+DIM*0+ZZ] -= tz;
 338
 339             }
 340
 341             /**************************
 342              * CALCULATE INTERACTIONS *
 343              **************************/
 344
 345             if (rsq20<rcutoff2)
 346             {
 347
 348             r20              = rsq20*rinv20;
 349
 350             qq20             = iq2*jq0;
 351
 352             /* EWALD ELECTROSTATICS */
 353
 354             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 355             ewrt             = r20*ewtabscale;
 356             ewitab           = ewrt;
 357             eweps            = ewrt-ewitab;
 358             ewitab           = 4*ewitab;
 359             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 360             velec            = qq20*(rinv20-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 361             felec            = qq20*rinv20*(rinvsq20-felec);
 362
 363             d                = r20-rswitch;
 364             d                = (d>0.0) ? d : 0.0;
 365             d2               = d*d;
 366             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
 367
 368             dsw              = d2*(swF2+d*(swF3+d*swF4));
 369
 370             /* Evaluate switch function */
 371             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
 372             felec            = felec*sw - rinv20*velec*dsw;
 373             velec           *= sw;
 374
 375             /* Update potential sums from outer loop */
 376             velecsum        += velec;
 377
 378             fscal            = felec;
 379
 380             /* Calculate temporary vectorial force */
 381             tx               = fscal*dx20;
 382             ty               = fscal*dy20;
 383             tz               = fscal*dz20;
 384
 385             /* Update vectorial force */
 386             fix2            += tx;
 387             fiy2            += ty;
 388             fiz2            += tz;
 389             f[j_coord_offset+DIM*0+XX] -= tx;
 390             f[j_coord_offset+DIM*0+YY] -= ty;
 391             f[j_coord_offset+DIM*0+ZZ] -= tz;
 392
 393             }
 394
 395             /* Inner loop uses 193 flops */
 396         }
 397         /* End of innermost loop */
 398
 399         tx = ty = tz = 0;
 400         f[i_coord_offset+DIM*0+XX] += fix0;
 401         f[i_coord_offset+DIM*0+YY] += fiy0;
 402         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 403         tx                         += fix0;
 404         ty                         += fiy0;
 405         tz                         += fiz0;
 406         f[i_coord_offset+DIM*1+XX] += fix1;
 407         f[i_coord_offset+DIM*1+YY] += fiy1;
 408         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 409         tx                         += fix1;
 410         ty                         += fiy1;
 411         tz                         += fiz1;
 412         f[i_coord_offset+DIM*2+XX] += fix2;
 413         f[i_coord_offset+DIM*2+YY] += fiy2;
 414         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 415         tx                         += fix2;
 416         ty                         += fiy2;
 417         tz                         += fiz2;
 418         fshift[i_shift_offset+XX]  += tx;
 419         fshift[i_shift_offset+YY]  += ty;
 420         fshift[i_shift_offset+ZZ]  += tz;
 421
 422         ggid                        = gid[iidx];
 423         /* Update potential energies */
 424         kernel_data->energygrp_elec[ggid] += velecsum;
 425         kernel_data->energygrp_vdw[ggid] += vvdwsum;
 426
 427         /* Increment number of inner iterations */
 428         inneriter                  += j_index_end - j_index_start;
 429
 430         /* Outer loop uses 32 flops */
 431     }
 432
 433     /* Increment number of outer iterations */
 434     outeriter        += nri;
 435
 436     /* Update outer/inner flops */
 437
 438     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W3_VF,outeriter*32 + inneriter*193);
 439 }
 440 /*
 441  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSw_VdwLJSw_GeomW3P1_F_c
 442  * Electrostatics interaction: Ewald
 443  * VdW interaction:            LennardJones
 444  * Geometry:                   Water3-Particle
 445  * Calculate force/pot:        Force
 446  */
 447 void
 448 nb_kernel_ElecEwSw_VdwLJSw_GeomW3P1_F_c
 449                     (t_nblist                    * gmx_restrict       nlist,
 450                      rvec                        * gmx_restrict          xx,
 451                      rvec                        * gmx_restrict          ff,
 452                      t_forcerec                  * gmx_restrict          fr,
 453                      t_mdatoms                   * gmx_restrict     mdatoms,
 454                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 455                      t_nrnb                      * gmx_restrict        nrnb)
 456 {
 457     int              i_shift_offset,i_coord_offset,j_coord_offset;
 458     int              j_index_start,j_index_end;
 459     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 460     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 461     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 462     real             *shiftvec,*fshift,*x,*f;
 463     int              vdwioffset0;
 464     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 465     int              vdwioffset1;
 466     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 467     int              vdwioffset2;
 468     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 469     int              vdwjidx0;
 470     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 471     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
 472     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
 473     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
 474     real             velec,felec,velecsum,facel,crf,krf,krf2;
 475     real             *charge;
 476     int              nvdwtype;
 477     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
 478     int              *vdwtype;
 479     real             *vdwparam;
 480     int              ewitab;
 481     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
 482     real             *ewtab;
 483     real             rswitch,swV3,swV4,swV5,swF2,swF3,swF4,d,d2,sw,dsw;
 484
 485     x                = xx[0];
 486     f                = ff[0];
 487
 488     nri              = nlist->nri;
 489     iinr             = nlist->iinr;
 490     jindex           = nlist->jindex;
 491     jjnr             = nlist->jjnr;
 492     shiftidx         = nlist->shift;
 493     gid              = nlist->gid;
 494     shiftvec         = fr->shift_vec[0];
 495     fshift           = fr->fshift[0];
 496     facel            = fr->epsfac;
 497     charge           = mdatoms->chargeA;
 498     nvdwtype         = fr->ntype;
 499     vdwparam         = fr->nbfp;
 500     vdwtype          = mdatoms->typeA;
 501
 502     sh_ewald         = fr->ic->sh_ewald;
 503     ewtab            = fr->ic->tabq_coul_FDV0;
 504     ewtabscale       = fr->ic->tabq_scale;
 505     ewtabhalfspace   = 0.5/ewtabscale;
 506
 507     /* Setup water-specific parameters */
 508     inr              = nlist->iinr[0];
 509     iq0              = facel*charge[inr+0];
 510     iq1              = facel*charge[inr+1];
 511     iq2              = facel*charge[inr+2];
 512     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 513
 514     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 515     rcutoff          = fr->rcoulomb;
 516     rcutoff2         = rcutoff*rcutoff;
 517
 518     rswitch          = fr->rcoulomb_switch;
 519     /* Setup switch parameters */
 520     d                = rcutoff-rswitch;
 521     swV3             = -10.0/(d*d*d);
 522     swV4             =  15.0/(d*d*d*d);
 523     swV5             =  -6.0/(d*d*d*d*d);
 524     swF2             = -30.0/(d*d*d);
 525     swF3             =  60.0/(d*d*d*d);
 526     swF4             = -30.0/(d*d*d*d*d);
 527
 528     outeriter        = 0;
 529     inneriter        = 0;
 530
 531     /* Start outer loop over neighborlists */
 532     for(iidx=0; iidx<nri; iidx++)
 533     {
 534         /* Load shift vector for this list */
 535         i_shift_offset   = DIM*shiftidx[iidx];
 536         shX              = shiftvec[i_shift_offset+XX];
 537         shY              = shiftvec[i_shift_offset+YY];
 538         shZ              = shiftvec[i_shift_offset+ZZ];
 539
 540         /* Load limits for loop over neighbors */
 541         j_index_start    = jindex[iidx];
 542         j_index_end      = jindex[iidx+1];
 543
 544         /* Get outer coordinate index */
 545         inr              = iinr[iidx];
 546         i_coord_offset   = DIM*inr;
 547
 548         /* Load i particle coords and add shift vector */
 549         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 550         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 551         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 552         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 553         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 554         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 555         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 556         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 557         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 558
 559         fix0             = 0.0;
 560         fiy0             = 0.0;
 561         fiz0             = 0.0;
 562         fix1             = 0.0;
 563         fiy1             = 0.0;
 564         fiz1             = 0.0;
 565         fix2             = 0.0;
 566         fiy2             = 0.0;
 567         fiz2             = 0.0;
 568
 569         /* Start inner kernel loop */
 570         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 571         {
 572             /* Get j neighbor index, and coordinate index */
 573             jnr              = jjnr[jidx];
 574             j_coord_offset   = DIM*jnr;
 575
 576             /* load j atom coordinates */
 577             jx0              = x[j_coord_offset+DIM*0+XX];
 578             jy0              = x[j_coord_offset+DIM*0+YY];
 579             jz0              = x[j_coord_offset+DIM*0+ZZ];
 580
 581             /* Calculate displacement vector */
 582             dx00             = ix0 - jx0;
 583             dy00             = iy0 - jy0;
 584             dz00             = iz0 - jz0;
 585             dx10             = ix1 - jx0;
 586             dy10             = iy1 - jy0;
 587             dz10             = iz1 - jz0;
 588             dx20             = ix2 - jx0;
 589             dy20             = iy2 - jy0;
 590             dz20             = iz2 - jz0;
 591
 592             /* Calculate squared distance and things based on it */
 593             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 594             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 595             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 596
 597             rinv00           = gmx_invsqrt(rsq00);
 598             rinv10           = gmx_invsqrt(rsq10);
 599             rinv20           = gmx_invsqrt(rsq20);
 600
 601             rinvsq00         = rinv00*rinv00;
 602             rinvsq10         = rinv10*rinv10;
 603             rinvsq20         = rinv20*rinv20;
 604
 605             /* Load parameters for j particles */
 606             jq0              = charge[jnr+0];
 607             vdwjidx0         = 2*vdwtype[jnr+0];
 608
 609             /**************************
 610              * CALCULATE INTERACTIONS *
 611              **************************/
 612
 613             if (rsq00<rcutoff2)
 614             {
 615
 616             r00              = rsq00*rinv00;
 617
 618             qq00             = iq0*jq0;
 619             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 620             c12_00           = vdwparam[vdwioffset0+vdwjidx0+1];
 621
 622             /* EWALD ELECTROSTATICS */
 623
 624             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 625             ewrt             = r00*ewtabscale;
 626             ewitab           = ewrt;
 627             eweps            = ewrt-ewitab;
 628             ewitab           = 4*ewitab;
 629             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 630             velec            = qq00*(rinv00-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 631             felec            = qq00*rinv00*(rinvsq00-felec);
 632
 633             /* LENNARD-JONES DISPERSION/REPULSION */
 634
 635             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 636             vvdw6            = c6_00*rinvsix;
 637             vvdw12           = c12_00*rinvsix*rinvsix;
 638             vvdw             = vvdw12*(1.0/12.0) - vvdw6*(1.0/6.0);
 639             fvdw             = (vvdw12-vvdw6)*rinvsq00;
 640
 641             d                = r00-rswitch;
 642             d                = (d>0.0) ? d : 0.0;
 643             d2               = d*d;
 644             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
 645
 646             dsw              = d2*(swF2+d*(swF3+d*swF4));
 647
 648             /* Evaluate switch function */
 649             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
 650             felec            = felec*sw - rinv00*velec*dsw;
 651             fvdw             = fvdw*sw - rinv00*vvdw*dsw;
 652
 653             fscal            = felec+fvdw;
 654
 655             /* Calculate temporary vectorial force */
 656             tx               = fscal*dx00;
 657             ty               = fscal*dy00;
 658             tz               = fscal*dz00;
 659
 660             /* Update vectorial force */
 661             fix0            += tx;
 662             fiy0            += ty;
 663             fiz0            += tz;
 664             f[j_coord_offset+DIM*0+XX] -= tx;
 665             f[j_coord_offset+DIM*0+YY] -= ty;
 666             f[j_coord_offset+DIM*0+ZZ] -= tz;
 667
 668             }
 669
 670             /**************************
 671              * CALCULATE INTERACTIONS *
 672              **************************/
 673
 674             if (rsq10<rcutoff2)
 675             {
 676
 677             r10              = rsq10*rinv10;
 678
 679             qq10             = iq1*jq0;
 680
 681             /* EWALD ELECTROSTATICS */
 682
 683             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 684             ewrt             = r10*ewtabscale;
 685             ewitab           = ewrt;
 686             eweps            = ewrt-ewitab;
 687             ewitab           = 4*ewitab;
 688             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 689             velec            = qq10*(rinv10-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 690             felec            = qq10*rinv10*(rinvsq10-felec);
 691
 692             d                = r10-rswitch;
 693             d                = (d>0.0) ? d : 0.0;
 694             d2               = d*d;
 695             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
 696
 697             dsw              = d2*(swF2+d*(swF3+d*swF4));
 698
 699             /* Evaluate switch function */
 700             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
 701             felec            = felec*sw - rinv10*velec*dsw;
 702
 703             fscal            = felec;
 704
 705             /* Calculate temporary vectorial force */
 706             tx               = fscal*dx10;
 707             ty               = fscal*dy10;
 708             tz               = fscal*dz10;
 709
 710             /* Update vectorial force */
 711             fix1            += tx;
 712             fiy1            += ty;
 713             fiz1            += tz;
 714             f[j_coord_offset+DIM*0+XX] -= tx;
 715             f[j_coord_offset+DIM*0+YY] -= ty;
 716             f[j_coord_offset+DIM*0+ZZ] -= tz;
 717
 718             }
 719
 720             /**************************
 721              * CALCULATE INTERACTIONS *
 722              **************************/
 723
 724             if (rsq20<rcutoff2)
 725             {
 726
 727             r20              = rsq20*rinv20;
 728
 729             qq20             = iq2*jq0;
 730
 731             /* EWALD ELECTROSTATICS */
 732
 733             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 734             ewrt             = r20*ewtabscale;
 735             ewitab           = ewrt;
 736             eweps            = ewrt-ewitab;
 737             ewitab           = 4*ewitab;
 738             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 739             velec            = qq20*(rinv20-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 740             felec            = qq20*rinv20*(rinvsq20-felec);
 741
 742             d                = r20-rswitch;
 743             d                = (d>0.0) ? d : 0.0;
 744             d2               = d*d;
 745             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
 746
 747             dsw              = d2*(swF2+d*(swF3+d*swF4));
 748
 749             /* Evaluate switch function */
 750             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
 751             felec            = felec*sw - rinv20*velec*dsw;
 752
 753             fscal            = felec;
 754
 755             /* Calculate temporary vectorial force */
 756             tx               = fscal*dx20;
 757             ty               = fscal*dy20;
 758             tz               = fscal*dz20;
 759
 760             /* Update vectorial force */
 761             fix2            += tx;
 762             fiy2            += ty;
 763             fiz2            += tz;
 764             f[j_coord_offset+DIM*0+XX] -= tx;
 765             f[j_coord_offset+DIM*0+YY] -= ty;
 766             f[j_coord_offset+DIM*0+ZZ] -= tz;
 767
 768             }
 769
 770             /* Inner loop uses 185 flops */
 771         }
 772         /* End of innermost loop */
 773
 774         tx = ty = tz = 0;
 775         f[i_coord_offset+DIM*0+XX] += fix0;
 776         f[i_coord_offset+DIM*0+YY] += fiy0;
 777         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 778         tx                         += fix0;
 779         ty                         += fiy0;
 780         tz                         += fiz0;
 781         f[i_coord_offset+DIM*1+XX] += fix1;
 782         f[i_coord_offset+DIM*1+YY] += fiy1;
 783         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 784         tx                         += fix1;
 785         ty                         += fiy1;
 786         tz                         += fiz1;
 787         f[i_coord_offset+DIM*2+XX] += fix2;
 788         f[i_coord_offset+DIM*2+YY] += fiy2;
 789         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 790         tx                         += fix2;
 791         ty                         += fiy2;
 792         tz                         += fiz2;
 793         fshift[i_shift_offset+XX]  += tx;
 794         fshift[i_shift_offset+YY]  += ty;
 795         fshift[i_shift_offset+ZZ]  += tz;
 796
 797         /* Increment number of inner iterations */
 798         inneriter                  += j_index_end - j_index_start;
 799
 800         /* Outer loop uses 30 flops */
 801     }
 802
 803     /* Increment number of outer iterations */
 804     outeriter        += nri;
 805
 806     /* Update outer/inner flops */
 807
 808     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W3_F,outeriter*30 + inneriter*185);
 809 }