src/gromacs/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecEwSh_VdwNone_GeomP1P1_c.c

   1 /*
   2  * Note: this file was generated by the Gromacs c kernel generator.
   3  *
   4  *                This source code is part of
   5  *
   6  *                 G   R   O   M   A   C   S
   7  *
   8  * Copyright (c) 2001-2012, The GROMACS Development Team
   9  *
  10  * Gromacs is a library for molecular simulation and trajectory analysis,
  11  * written by Erik Lindahl, David van der Spoel, Berk Hess, and others - for
  12  * a full list of developers and information, check out http://www.gromacs.org
  13  *
  14  * This program is free software; you can redistribute it and/or modify it under
  15  * the terms of the GNU Lesser General Public License as published by the Free
  16  * Software Foundation; either version 2 of the License, or (at your option) any
  17  * later version.
  18  *
  19  * To help fund GROMACS development, we humbly ask that you cite
  20  * the papers people have written on it - you can find them on the website.
  21  */
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <math.h>
  27
  28 #include "../nb_kernel.h"
  29 #include "types/simple.h"
  30 #include "vec.h"
  31 #include "nrnb.h"
  32
  33 /*
  34  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSh_VdwNone_GeomP1P1_VF_c
  35  * Electrostatics interaction: Ewald
  36  * VdW interaction:            None
  37  * Geometry:                   Particle-Particle
  38  * Calculate force/pot:        PotentialAndForce
  39  */
  40 void
  41 nb_kernel_ElecEwSh_VdwNone_GeomP1P1_VF_c
  42                     (t_nblist * gmx_restrict                nlist,
  43                      rvec * gmx_restrict                    xx,
  44                      rvec * gmx_restrict                    ff,
  45                      t_forcerec * gmx_restrict              fr,
  46                      t_mdatoms * gmx_restrict               mdatoms,
  47                      nb_kernel_data_t * gmx_restrict        kernel_data,
  48                      t_nrnb * gmx_restrict                  nrnb)
  49 {
  50     int              i_shift_offset,i_coord_offset,j_coord_offset;
  51     int              j_index_start,j_index_end;
  52     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
  53     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
  54     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  55     real             *shiftvec,*fshift,*x,*f;
  56     int              vdwioffset0;
  57     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  58     int              vdwjidx0;
  59     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  60     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
  61     real             velec,felec,velecsum,facel,crf,krf,krf2;
  62     real             *charge;
  63     int              ewitab;
  64     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
  65     real             *ewtab;
  66
  67     x                = xx[0];
  68     f                = ff[0];
  69
  70     nri              = nlist->nri;
  71     iinr             = nlist->iinr;
  72     jindex           = nlist->jindex;
  73     jjnr             = nlist->jjnr;
  74     shiftidx         = nlist->shift;
  75     gid              = nlist->gid;
  76     shiftvec         = fr->shift_vec[0];
  77     fshift           = fr->fshift[0];
  78     facel            = fr->epsfac;
  79     charge           = mdatoms->chargeA;
  80
  81     sh_ewald         = fr->ic->sh_ewald;
  82     ewtab            = fr->ic->tabq_coul_FDV0;
  83     ewtabscale       = fr->ic->tabq_scale;
  84     ewtabhalfspace   = 0.5/ewtabscale;
  85
  86     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
  87     rcutoff          = fr->rcoulomb;
  88     rcutoff2         = rcutoff*rcutoff;
  89
  90     outeriter        = 0;
  91     inneriter        = 0;
  92
  93     /* Start outer loop over neighborlists */
  94     for(iidx=0; iidx<nri; iidx++)
  95     {
  96         /* Load shift vector for this list */
  97         i_shift_offset   = DIM*shiftidx[iidx];
  98         shX              = shiftvec[i_shift_offset+XX];
  99         shY              = shiftvec[i_shift_offset+YY];
 100         shZ              = shiftvec[i_shift_offset+ZZ];
 101
 102         /* Load limits for loop over neighbors */
 103         j_index_start    = jindex[iidx];
 104         j_index_end      = jindex[iidx+1];
 105
 106         /* Get outer coordinate index */
 107         inr              = iinr[iidx];
 108         i_coord_offset   = DIM*inr;
 109
 110         /* Load i particle coords and add shift vector */
 111         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 112         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 113         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 114
 115         fix0             = 0.0;
 116         fiy0             = 0.0;
 117         fiz0             = 0.0;
 118
 119         /* Load parameters for i particles */
 120         iq0              = facel*charge[inr+0];
 121
 122         /* Reset potential sums */
 123         velecsum         = 0.0;
 124
 125         /* Start inner kernel loop */
 126         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 127         {
 128             /* Get j neighbor index, and coordinate index */
 129             jnr              = jjnr[jidx];
 130             j_coord_offset   = DIM*jnr;
 131
 132             /* load j atom coordinates */
 133             jx0              = x[j_coord_offset+DIM*0+XX];
 134             jy0              = x[j_coord_offset+DIM*0+YY];
 135             jz0              = x[j_coord_offset+DIM*0+ZZ];
 136
 137             /* Calculate displacement vector */
 138             dx00             = ix0 - jx0;
 139             dy00             = iy0 - jy0;
 140             dz00             = iz0 - jz0;
 141
 142             /* Calculate squared distance and things based on it */
 143             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 144
 145             rinv00           = gmx_invsqrt(rsq00);
 146
 147             rinvsq00         = rinv00*rinv00;
 148
 149             /* Load parameters for j particles */
 150             jq0              = charge[jnr+0];
 151
 152             /**************************
 153              * CALCULATE INTERACTIONS *
 154              **************************/
 155
 156             if (rsq00<rcutoff2)
 157             {
 158
 159             r00              = rsq00*rinv00;
 160
 161             qq00             = iq0*jq0;
 162
 163             /* EWALD ELECTROSTATICS */
 164
 165             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 166             ewrt             = r00*ewtabscale;
 167             ewitab           = ewrt;
 168             eweps            = ewrt-ewitab;
 169             ewitab           = 4*ewitab;
 170             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
 171             velec            = qq00*((rinv00-sh_ewald)-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
 172             felec            = qq00*rinv00*(rinvsq00-felec);
 173
 174             /* Update potential sums from outer loop */
 175             velecsum        += velec;
 176
 177             fscal            = felec;
 178
 179             /* Calculate temporary vectorial force */
 180             tx               = fscal*dx00;
 181             ty               = fscal*dy00;
 182             tz               = fscal*dz00;
 183
 184             /* Update vectorial force */
 185             fix0            += tx;
 186             fiy0            += ty;
 187             fiz0            += tz;
 188             f[j_coord_offset+DIM*0+XX] -= tx;
 189             f[j_coord_offset+DIM*0+YY] -= ty;
 190             f[j_coord_offset+DIM*0+ZZ] -= tz;
 191
 192             }
 193
 194             /* Inner loop uses 42 flops */
 195         }
 196         /* End of innermost loop */
 197
 198         tx = ty = tz = 0;
 199         f[i_coord_offset+DIM*0+XX] += fix0;
 200         f[i_coord_offset+DIM*0+YY] += fiy0;
 201         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 202         tx                         += fix0;
 203         ty                         += fiy0;
 204         tz                         += fiz0;
 205         fshift[i_shift_offset+XX]  += tx;
 206         fshift[i_shift_offset+YY]  += ty;
 207         fshift[i_shift_offset+ZZ]  += tz;
 208
 209         ggid                        = gid[iidx];
 210         /* Update potential energies */
 211         kernel_data->energygrp_elec[ggid] += velecsum;
 212
 213         /* Increment number of inner iterations */
 214         inneriter                  += j_index_end - j_index_start;
 215
 216         /* Outer loop uses 14 flops */
 217     }
 218
 219     /* Increment number of outer iterations */
 220     outeriter        += nri;
 221
 222     /* Update outer/inner flops */
 223
 224     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VF,outeriter*14 + inneriter*42);
 225 }
 226 /*
 227  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSh_VdwNone_GeomP1P1_F_c
 228  * Electrostatics interaction: Ewald
 229  * VdW interaction:            None
 230  * Geometry:                   Particle-Particle
 231  * Calculate force/pot:        Force
 232  */
 233 void
 234 nb_kernel_ElecEwSh_VdwNone_GeomP1P1_F_c
 235                     (t_nblist * gmx_restrict                nlist,
 236                      rvec * gmx_restrict                    xx,
 237                      rvec * gmx_restrict                    ff,
 238                      t_forcerec * gmx_restrict              fr,
 239                      t_mdatoms * gmx_restrict               mdatoms,
 240                      nb_kernel_data_t * gmx_restrict        kernel_data,
 241                      t_nrnb * gmx_restrict                  nrnb)
 242 {
 243     int              i_shift_offset,i_coord_offset,j_coord_offset;
 244     int              j_index_start,j_index_end;
 245     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 246     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 247     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 248     real             *shiftvec,*fshift,*x,*f;
 249     int              vdwioffset0;
 250     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 251     int              vdwjidx0;
 252     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 253     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
 254     real             velec,felec,velecsum,facel,crf,krf,krf2;
 255     real             *charge;
 256     int              ewitab;
 257     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
 258     real             *ewtab;
 259
 260     x                = xx[0];
 261     f                = ff[0];
 262
 263     nri              = nlist->nri;
 264     iinr             = nlist->iinr;
 265     jindex           = nlist->jindex;
 266     jjnr             = nlist->jjnr;
 267     shiftidx         = nlist->shift;
 268     gid              = nlist->gid;
 269     shiftvec         = fr->shift_vec[0];
 270     fshift           = fr->fshift[0];
 271     facel            = fr->epsfac;
 272     charge           = mdatoms->chargeA;
 273
 274     sh_ewald         = fr->ic->sh_ewald;
 275     ewtab            = fr->ic->tabq_coul_F;
 276     ewtabscale       = fr->ic->tabq_scale;
 277     ewtabhalfspace   = 0.5/ewtabscale;
 278
 279     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 280     rcutoff          = fr->rcoulomb;
 281     rcutoff2         = rcutoff*rcutoff;
 282
 283     outeriter        = 0;
 284     inneriter        = 0;
 285
 286     /* Start outer loop over neighborlists */
 287     for(iidx=0; iidx<nri; iidx++)
 288     {
 289         /* Load shift vector for this list */
 290         i_shift_offset   = DIM*shiftidx[iidx];
 291         shX              = shiftvec[i_shift_offset+XX];
 292         shY              = shiftvec[i_shift_offset+YY];
 293         shZ              = shiftvec[i_shift_offset+ZZ];
 294
 295         /* Load limits for loop over neighbors */
 296         j_index_start    = jindex[iidx];
 297         j_index_end      = jindex[iidx+1];
 298
 299         /* Get outer coordinate index */
 300         inr              = iinr[iidx];
 301         i_coord_offset   = DIM*inr;
 302
 303         /* Load i particle coords and add shift vector */
 304         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 305         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 306         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 307
 308         fix0             = 0.0;
 309         fiy0             = 0.0;
 310         fiz0             = 0.0;
 311
 312         /* Load parameters for i particles */
 313         iq0              = facel*charge[inr+0];
 314
 315         /* Start inner kernel loop */
 316         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 317         {
 318             /* Get j neighbor index, and coordinate index */
 319             jnr              = jjnr[jidx];
 320             j_coord_offset   = DIM*jnr;
 321
 322             /* load j atom coordinates */
 323             jx0              = x[j_coord_offset+DIM*0+XX];
 324             jy0              = x[j_coord_offset+DIM*0+YY];
 325             jz0              = x[j_coord_offset+DIM*0+ZZ];
 326
 327             /* Calculate displacement vector */
 328             dx00             = ix0 - jx0;
 329             dy00             = iy0 - jy0;
 330             dz00             = iz0 - jz0;
 331
 332             /* Calculate squared distance and things based on it */
 333             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 334
 335             rinv00           = gmx_invsqrt(rsq00);
 336
 337             rinvsq00         = rinv00*rinv00;
 338
 339             /* Load parameters for j particles */
 340             jq0              = charge[jnr+0];
 341
 342             /**************************
 343              * CALCULATE INTERACTIONS *
 344              **************************/
 345
 346             if (rsq00<rcutoff2)
 347             {
 348
 349             r00              = rsq00*rinv00;
 350
 351             qq00             = iq0*jq0;
 352
 353             /* EWALD ELECTROSTATICS */
 354
 355             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 356             ewrt             = r00*ewtabscale;
 357             ewitab           = ewrt;
 358             eweps            = ewrt-ewitab;
 359             felec            = (1.0-eweps)*ewtab[ewitab]+eweps*ewtab[ewitab+1];
 360             felec            = qq00*rinv00*(rinvsq00-felec);
 361
 362             fscal            = felec;
 363
 364             /* Calculate temporary vectorial force */
 365             tx               = fscal*dx00;
 366             ty               = fscal*dy00;
 367             tz               = fscal*dz00;
 368
 369             /* Update vectorial force */
 370             fix0            += tx;
 371             fiy0            += ty;
 372             fiz0            += tz;
 373             f[j_coord_offset+DIM*0+XX] -= tx;
 374             f[j_coord_offset+DIM*0+YY] -= ty;
 375             f[j_coord_offset+DIM*0+ZZ] -= tz;
 376
 377             }
 378
 379             /* Inner loop uses 34 flops */
 380         }
 381         /* End of innermost loop */
 382
 383         tx = ty = tz = 0;
 384         f[i_coord_offset+DIM*0+XX] += fix0;
 385         f[i_coord_offset+DIM*0+YY] += fiy0;
 386         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 387         tx                         += fix0;
 388         ty                         += fiy0;
 389         tz                         += fiz0;
 390         fshift[i_shift_offset+XX]  += tx;
 391         fshift[i_shift_offset+YY]  += ty;
 392         fshift[i_shift_offset+ZZ]  += tz;
 393
 394         /* Increment number of inner iterations */
 395         inneriter                  += j_index_end - j_index_start;
 396
 397         /* Outer loop uses 13 flops */
 398     }
 399
 400     /* Increment number of outer iterations */
 401     outeriter        += nri;
 402
 403     /* Update outer/inner flops */
 404
 405     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_F,outeriter*13 + inneriter*34);
 406 }