src/gromacs/gmxlib/nonbonded/nb_kernel_sse2_double/nb_kernel_ElecNone_VdwLJ_GeomP1P1_sse2_double.cpp

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2012,2013,2014,2015,2017,2018, 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  *
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  35 /*
  36  * Note: this file was generated by the GROMACS sse2_double kernel generator.
  37  */
  38 #include "gmxpre.h"
  39
  40 #include "config.h"
  41
  42 #include <math.h>
  43
  44 #include "../nb_kernel.h"
  45 #include "gromacs/gmxlib/nrnb.h"
  46
  47 #include "kernelutil_x86_sse2_double.h"
  48
  49 /*
  50  * Gromacs nonbonded kernel:   nb_kernel_ElecNone_VdwLJ_GeomP1P1_VF_sse2_double
  51  * Electrostatics interaction: None
  52  * VdW interaction:            LennardJones
  53  * Geometry:                   Particle-Particle
  54  * Calculate force/pot:        PotentialAndForce
  55  */
  56 void
  57 nb_kernel_ElecNone_VdwLJ_GeomP1P1_VF_sse2_double
  58                     (t_nblist                    * gmx_restrict       nlist,
  59                      rvec                        * gmx_restrict          xx,
  60                      rvec                        * gmx_restrict          ff,
  61                      struct t_forcerec           * gmx_restrict          fr,
  62                      t_mdatoms                   * gmx_restrict     mdatoms,
  63                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
  64                      t_nrnb                      * gmx_restrict        nrnb)
  65 {
  66     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
  67      * just 0 for non-waters.
  68      * Suffixes A,B refer to j loop unrolling done with SSE double precision, e.g. for the two different
  69      * jnr indices corresponding to data put in the four positions in the SIMD register.
  70      */
  71     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
  72     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
  73     int              jnrA,jnrB;
  74     int              j_coord_offsetA,j_coord_offsetB;
  75     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  76     real             rcutoff_scalar;
  77     real             *shiftvec,*fshift,*x,*f;
  78     __m128d          tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
  79     int              vdwioffset0;
  80     __m128d          ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  81     int              vdwjidx0A,vdwjidx0B;
  82     __m128d          jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  83     __m128d          dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
  84     int              nvdwtype;
  85     __m128d          rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
  86     int              *vdwtype;
  87     real             *vdwparam;
  88     __m128d          one_sixth   = _mm_set1_pd(1.0/6.0);
  89     __m128d          one_twelfth = _mm_set1_pd(1.0/12.0);
  90     __m128d          dummy_mask,cutoff_mask;
  91     __m128d          signbit   = gmx_mm_castsi128_pd( _mm_set_epi32(0x80000000,0x00000000,0x80000000,0x00000000) );
  92     __m128d          one     = _mm_set1_pd(1.0);
  93     __m128d          two     = _mm_set1_pd(2.0);
  94     x                = xx[0];
  95     f                = ff[0];
  96
  97     nri              = nlist->nri;
  98     iinr             = nlist->iinr;
  99     jindex           = nlist->jindex;
 100     jjnr             = nlist->jjnr;
 101     shiftidx         = nlist->shift;
 102     gid              = nlist->gid;
 103     shiftvec         = fr->shift_vec[0];
 104     fshift           = fr->fshift[0];
 105     nvdwtype         = fr->ntype;
 106     vdwparam         = fr->nbfp;
 107     vdwtype          = mdatoms->typeA;
 108
 109     /* Avoid stupid compiler warnings */
 110     jnrA = jnrB = 0;
 111     j_coord_offsetA = 0;
 112     j_coord_offsetB = 0;
 113
 114     outeriter        = 0;
 115     inneriter        = 0;
 116
 117     /* Start outer loop over neighborlists */
 118     for(iidx=0; iidx<nri; iidx++)
 119     {
 120         /* Load shift vector for this list */
 121         i_shift_offset   = DIM*shiftidx[iidx];
 122
 123         /* Load limits for loop over neighbors */
 124         j_index_start    = jindex[iidx];
 125         j_index_end      = jindex[iidx+1];
 126
 127         /* Get outer coordinate index */
 128         inr              = iinr[iidx];
 129         i_coord_offset   = DIM*inr;
 130
 131         /* Load i particle coords and add shift vector */
 132         gmx_mm_load_shift_and_1rvec_broadcast_pd(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 133
 134         fix0             = _mm_setzero_pd();
 135         fiy0             = _mm_setzero_pd();
 136         fiz0             = _mm_setzero_pd();
 137
 138         /* Load parameters for i particles */
 139         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 140
 141         /* Reset potential sums */
 142         vvdwsum          = _mm_setzero_pd();
 143
 144         /* Start inner kernel loop */
 145         for(jidx=j_index_start; jidx<j_index_end-1; jidx+=2)
 146         {
 147
 148             /* Get j neighbor index, and coordinate index */
 149             jnrA             = jjnr[jidx];
 150             jnrB             = jjnr[jidx+1];
 151             j_coord_offsetA  = DIM*jnrA;
 152             j_coord_offsetB  = DIM*jnrB;
 153
 154             /* load j atom coordinates */
 155             gmx_mm_load_1rvec_2ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
 156                                               &jx0,&jy0,&jz0);
 157
 158             /* Calculate displacement vector */
 159             dx00             = _mm_sub_pd(ix0,jx0);
 160             dy00             = _mm_sub_pd(iy0,jy0);
 161             dz00             = _mm_sub_pd(iz0,jz0);
 162
 163             /* Calculate squared distance and things based on it */
 164             rsq00            = gmx_mm_calc_rsq_pd(dx00,dy00,dz00);
 165
 166             rinvsq00         = sse2_inv_d(rsq00);
 167
 168             /* Load parameters for j particles */
 169             vdwjidx0A        = 2*vdwtype[jnrA+0];
 170             vdwjidx0B        = 2*vdwtype[jnrB+0];
 171
 172             /**************************
 173              * CALCULATE INTERACTIONS *
 174              **************************/
 175
 176             /* Compute parameters for interactions between i and j atoms */
 177             gmx_mm_load_2pair_swizzle_pd(vdwparam+vdwioffset0+vdwjidx0A,
 178                                          vdwparam+vdwioffset0+vdwjidx0B,&c6_00,&c12_00);
 179
 180             /* LENNARD-JONES DISPERSION/REPULSION */
 181
 182             rinvsix          = _mm_mul_pd(_mm_mul_pd(rinvsq00,rinvsq00),rinvsq00);
 183             vvdw6            = _mm_mul_pd(c6_00,rinvsix);
 184             vvdw12           = _mm_mul_pd(c12_00,_mm_mul_pd(rinvsix,rinvsix));
 185             vvdw             = _mm_sub_pd( _mm_mul_pd(vvdw12,one_twelfth) , _mm_mul_pd(vvdw6,one_sixth) );
 186             fvdw             = _mm_mul_pd(_mm_sub_pd(vvdw12,vvdw6),rinvsq00);
 187
 188             /* Update potential sum for this i atom from the interaction with this j atom. */
 189             vvdwsum          = _mm_add_pd(vvdwsum,vvdw);
 190
 191             fscal            = fvdw;
 192
 193             /* Calculate temporary vectorial force */
 194             tx               = _mm_mul_pd(fscal,dx00);
 195             ty               = _mm_mul_pd(fscal,dy00);
 196             tz               = _mm_mul_pd(fscal,dz00);
 197
 198             /* Update vectorial force */
 199             fix0             = _mm_add_pd(fix0,tx);
 200             fiy0             = _mm_add_pd(fiy0,ty);
 201             fiz0             = _mm_add_pd(fiz0,tz);
 202
 203             gmx_mm_decrement_1rvec_2ptr_swizzle_pd(f+j_coord_offsetA,f+j_coord_offsetB,tx,ty,tz);
 204
 205             /* Inner loop uses 32 flops */
 206         }
 207
 208         if(jidx<j_index_end)
 209         {
 210
 211             jnrA             = jjnr[jidx];
 212             j_coord_offsetA  = DIM*jnrA;
 213
 214             /* load j atom coordinates */
 215             gmx_mm_load_1rvec_1ptr_swizzle_pd(x+j_coord_offsetA,
 216                                               &jx0,&jy0,&jz0);
 217
 218             /* Calculate displacement vector */
 219             dx00             = _mm_sub_pd(ix0,jx0);
 220             dy00             = _mm_sub_pd(iy0,jy0);
 221             dz00             = _mm_sub_pd(iz0,jz0);
 222
 223             /* Calculate squared distance and things based on it */
 224             rsq00            = gmx_mm_calc_rsq_pd(dx00,dy00,dz00);
 225
 226             rinvsq00         = sse2_inv_d(rsq00);
 227
 228             /* Load parameters for j particles */
 229             vdwjidx0A        = 2*vdwtype[jnrA+0];
 230
 231             /**************************
 232              * CALCULATE INTERACTIONS *
 233              **************************/
 234
 235             /* Compute parameters for interactions between i and j atoms */
 236             gmx_mm_load_1pair_swizzle_pd(vdwparam+vdwioffset0+vdwjidx0A,&c6_00,&c12_00);
 237
 238             /* LENNARD-JONES DISPERSION/REPULSION */
 239
 240             rinvsix          = _mm_mul_pd(_mm_mul_pd(rinvsq00,rinvsq00),rinvsq00);
 241             vvdw6            = _mm_mul_pd(c6_00,rinvsix);
 242             vvdw12           = _mm_mul_pd(c12_00,_mm_mul_pd(rinvsix,rinvsix));
 243             vvdw             = _mm_sub_pd( _mm_mul_pd(vvdw12,one_twelfth) , _mm_mul_pd(vvdw6,one_sixth) );
 244             fvdw             = _mm_mul_pd(_mm_sub_pd(vvdw12,vvdw6),rinvsq00);
 245
 246             /* Update potential sum for this i atom from the interaction with this j atom. */
 247             vvdw             = _mm_unpacklo_pd(vvdw,_mm_setzero_pd());
 248             vvdwsum          = _mm_add_pd(vvdwsum,vvdw);
 249
 250             fscal            = fvdw;
 251
 252             fscal            = _mm_unpacklo_pd(fscal,_mm_setzero_pd());
 253
 254             /* Calculate temporary vectorial force */
 255             tx               = _mm_mul_pd(fscal,dx00);
 256             ty               = _mm_mul_pd(fscal,dy00);
 257             tz               = _mm_mul_pd(fscal,dz00);
 258
 259             /* Update vectorial force */
 260             fix0             = _mm_add_pd(fix0,tx);
 261             fiy0             = _mm_add_pd(fiy0,ty);
 262             fiz0             = _mm_add_pd(fiz0,tz);
 263
 264             gmx_mm_decrement_1rvec_1ptr_swizzle_pd(f+j_coord_offsetA,tx,ty,tz);
 265
 266             /* Inner loop uses 32 flops */
 267         }
 268
 269         /* End of innermost loop */
 270
 271         gmx_mm_update_iforce_1atom_swizzle_pd(fix0,fiy0,fiz0,
 272                                               f+i_coord_offset,fshift+i_shift_offset);
 273
 274         ggid                        = gid[iidx];
 275         /* Update potential energies */
 276         gmx_mm_update_1pot_pd(vvdwsum,kernel_data->energygrp_vdw+ggid);
 277
 278         /* Increment number of inner iterations */
 279         inneriter                  += j_index_end - j_index_start;
 280
 281         /* Outer loop uses 7 flops */
 282     }
 283
 284     /* Increment number of outer iterations */
 285     outeriter        += nri;
 286
 287     /* Update outer/inner flops */
 288
 289     inc_nrnb(nrnb,eNR_NBKERNEL_VDW_VF,outeriter*7 + inneriter*32);
 290 }
 291 /*
 292  * Gromacs nonbonded kernel:   nb_kernel_ElecNone_VdwLJ_GeomP1P1_F_sse2_double
 293  * Electrostatics interaction: None
 294  * VdW interaction:            LennardJones
 295  * Geometry:                   Particle-Particle
 296  * Calculate force/pot:        Force
 297  */
 298 void
 299 nb_kernel_ElecNone_VdwLJ_GeomP1P1_F_sse2_double
 300                     (t_nblist                    * gmx_restrict       nlist,
 301                      rvec                        * gmx_restrict          xx,
 302                      rvec                        * gmx_restrict          ff,
 303                      struct t_forcerec           * gmx_restrict          fr,
 304                      t_mdatoms                   * gmx_restrict     mdatoms,
 305                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 306                      t_nrnb                      * gmx_restrict        nrnb)
 307 {
 308     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
 309      * just 0 for non-waters.
 310      * Suffixes A,B refer to j loop unrolling done with SSE double precision, e.g. for the two different
 311      * jnr indices corresponding to data put in the four positions in the SIMD register.
 312      */
 313     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
 314     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
 315     int              jnrA,jnrB;
 316     int              j_coord_offsetA,j_coord_offsetB;
 317     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 318     real             rcutoff_scalar;
 319     real             *shiftvec,*fshift,*x,*f;
 320     __m128d          tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
 321     int              vdwioffset0;
 322     __m128d          ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 323     int              vdwjidx0A,vdwjidx0B;
 324     __m128d          jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 325     __m128d          dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
 326     int              nvdwtype;
 327     __m128d          rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
 328     int              *vdwtype;
 329     real             *vdwparam;
 330     __m128d          one_sixth   = _mm_set1_pd(1.0/6.0);
 331     __m128d          one_twelfth = _mm_set1_pd(1.0/12.0);
 332     __m128d          dummy_mask,cutoff_mask;
 333     __m128d          signbit   = gmx_mm_castsi128_pd( _mm_set_epi32(0x80000000,0x00000000,0x80000000,0x00000000) );
 334     __m128d          one     = _mm_set1_pd(1.0);
 335     __m128d          two     = _mm_set1_pd(2.0);
 336     x                = xx[0];
 337     f                = ff[0];
 338
 339     nri              = nlist->nri;
 340     iinr             = nlist->iinr;
 341     jindex           = nlist->jindex;
 342     jjnr             = nlist->jjnr;
 343     shiftidx         = nlist->shift;
 344     gid              = nlist->gid;
 345     shiftvec         = fr->shift_vec[0];
 346     fshift           = fr->fshift[0];
 347     nvdwtype         = fr->ntype;
 348     vdwparam         = fr->nbfp;
 349     vdwtype          = mdatoms->typeA;
 350
 351     /* Avoid stupid compiler warnings */
 352     jnrA = jnrB = 0;
 353     j_coord_offsetA = 0;
 354     j_coord_offsetB = 0;
 355
 356     outeriter        = 0;
 357     inneriter        = 0;
 358
 359     /* Start outer loop over neighborlists */
 360     for(iidx=0; iidx<nri; iidx++)
 361     {
 362         /* Load shift vector for this list */
 363         i_shift_offset   = DIM*shiftidx[iidx];
 364
 365         /* Load limits for loop over neighbors */
 366         j_index_start    = jindex[iidx];
 367         j_index_end      = jindex[iidx+1];
 368
 369         /* Get outer coordinate index */
 370         inr              = iinr[iidx];
 371         i_coord_offset   = DIM*inr;
 372
 373         /* Load i particle coords and add shift vector */
 374         gmx_mm_load_shift_and_1rvec_broadcast_pd(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 375
 376         fix0             = _mm_setzero_pd();
 377         fiy0             = _mm_setzero_pd();
 378         fiz0             = _mm_setzero_pd();
 379
 380         /* Load parameters for i particles */
 381         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 382
 383         /* Start inner kernel loop */
 384         for(jidx=j_index_start; jidx<j_index_end-1; jidx+=2)
 385         {
 386
 387             /* Get j neighbor index, and coordinate index */
 388             jnrA             = jjnr[jidx];
 389             jnrB             = jjnr[jidx+1];
 390             j_coord_offsetA  = DIM*jnrA;
 391             j_coord_offsetB  = DIM*jnrB;
 392
 393             /* load j atom coordinates */
 394             gmx_mm_load_1rvec_2ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
 395                                               &jx0,&jy0,&jz0);
 396
 397             /* Calculate displacement vector */
 398             dx00             = _mm_sub_pd(ix0,jx0);
 399             dy00             = _mm_sub_pd(iy0,jy0);
 400             dz00             = _mm_sub_pd(iz0,jz0);
 401
 402             /* Calculate squared distance and things based on it */
 403             rsq00            = gmx_mm_calc_rsq_pd(dx00,dy00,dz00);
 404
 405             rinvsq00         = sse2_inv_d(rsq00);
 406
 407             /* Load parameters for j particles */
 408             vdwjidx0A        = 2*vdwtype[jnrA+0];
 409             vdwjidx0B        = 2*vdwtype[jnrB+0];
 410
 411             /**************************
 412              * CALCULATE INTERACTIONS *
 413              **************************/
 414
 415             /* Compute parameters for interactions between i and j atoms */
 416             gmx_mm_load_2pair_swizzle_pd(vdwparam+vdwioffset0+vdwjidx0A,
 417                                          vdwparam+vdwioffset0+vdwjidx0B,&c6_00,&c12_00);
 418
 419             /* LENNARD-JONES DISPERSION/REPULSION */
 420
 421             rinvsix          = _mm_mul_pd(_mm_mul_pd(rinvsq00,rinvsq00),rinvsq00);
 422             fvdw             = _mm_mul_pd(_mm_sub_pd(_mm_mul_pd(c12_00,rinvsix),c6_00),_mm_mul_pd(rinvsix,rinvsq00));
 423
 424             fscal            = fvdw;
 425
 426             /* Calculate temporary vectorial force */
 427             tx               = _mm_mul_pd(fscal,dx00);
 428             ty               = _mm_mul_pd(fscal,dy00);
 429             tz               = _mm_mul_pd(fscal,dz00);
 430
 431             /* Update vectorial force */
 432             fix0             = _mm_add_pd(fix0,tx);
 433             fiy0             = _mm_add_pd(fiy0,ty);
 434             fiz0             = _mm_add_pd(fiz0,tz);
 435
 436             gmx_mm_decrement_1rvec_2ptr_swizzle_pd(f+j_coord_offsetA,f+j_coord_offsetB,tx,ty,tz);
 437
 438             /* Inner loop uses 27 flops */
 439         }
 440
 441         if(jidx<j_index_end)
 442         {
 443
 444             jnrA             = jjnr[jidx];
 445             j_coord_offsetA  = DIM*jnrA;
 446
 447             /* load j atom coordinates */
 448             gmx_mm_load_1rvec_1ptr_swizzle_pd(x+j_coord_offsetA,
 449                                               &jx0,&jy0,&jz0);
 450
 451             /* Calculate displacement vector */
 452             dx00             = _mm_sub_pd(ix0,jx0);
 453             dy00             = _mm_sub_pd(iy0,jy0);
 454             dz00             = _mm_sub_pd(iz0,jz0);
 455
 456             /* Calculate squared distance and things based on it */
 457             rsq00            = gmx_mm_calc_rsq_pd(dx00,dy00,dz00);
 458
 459             rinvsq00         = sse2_inv_d(rsq00);
 460
 461             /* Load parameters for j particles */
 462             vdwjidx0A        = 2*vdwtype[jnrA+0];
 463
 464             /**************************
 465              * CALCULATE INTERACTIONS *
 466              **************************/
 467
 468             /* Compute parameters for interactions between i and j atoms */
 469             gmx_mm_load_1pair_swizzle_pd(vdwparam+vdwioffset0+vdwjidx0A,&c6_00,&c12_00);
 470
 471             /* LENNARD-JONES DISPERSION/REPULSION */
 472
 473             rinvsix          = _mm_mul_pd(_mm_mul_pd(rinvsq00,rinvsq00),rinvsq00);
 474             fvdw             = _mm_mul_pd(_mm_sub_pd(_mm_mul_pd(c12_00,rinvsix),c6_00),_mm_mul_pd(rinvsix,rinvsq00));
 475
 476             fscal            = fvdw;
 477
 478             fscal            = _mm_unpacklo_pd(fscal,_mm_setzero_pd());
 479
 480             /* Calculate temporary vectorial force */
 481             tx               = _mm_mul_pd(fscal,dx00);
 482             ty               = _mm_mul_pd(fscal,dy00);
 483             tz               = _mm_mul_pd(fscal,dz00);
 484
 485             /* Update vectorial force */
 486             fix0             = _mm_add_pd(fix0,tx);
 487             fiy0             = _mm_add_pd(fiy0,ty);
 488             fiz0             = _mm_add_pd(fiz0,tz);
 489
 490             gmx_mm_decrement_1rvec_1ptr_swizzle_pd(f+j_coord_offsetA,tx,ty,tz);
 491
 492             /* Inner loop uses 27 flops */
 493         }
 494
 495         /* End of innermost loop */
 496
 497         gmx_mm_update_iforce_1atom_swizzle_pd(fix0,fiy0,fiz0,
 498                                               f+i_coord_offset,fshift+i_shift_offset);
 499
 500         /* Increment number of inner iterations */
 501         inneriter                  += j_index_end - j_index_start;
 502
 503         /* Outer loop uses 6 flops */
 504     }
 505
 506     /* Increment number of outer iterations */
 507     outeriter        += nri;
 508
 509     /* Update outer/inner flops */
 510
 511     inc_nrnb(nrnb,eNR_NBKERNEL_VDW_F,outeriter*6 + inneriter*27);
 512 }