src/gromacs/gmxlib/nonbonded/nb_kernel_sse2_single/nb_kernel_ElecCoul_VdwNone_GeomP1P1_sse2_single.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
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  11  * as published by the Free Software Foundation; either version 2.1
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  35 /*
  36  * Note: this file was generated by the GROMACS sse2_single 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/legacyheaders/types/simple.h"
  46 #include "gromacs/math/vec.h"
  47 #include "gromacs/legacyheaders/nrnb.h"
  48
  49 #include "gromacs/simd/math_x86_sse2_single.h"
  50 #include "kernelutil_x86_sse2_single.h"
  51
  52 /*
  53  * Gromacs nonbonded kernel:   nb_kernel_ElecCoul_VdwNone_GeomP1P1_VF_sse2_single
  54  * Electrostatics interaction: Coulomb
  55  * VdW interaction:            None
  56  * Geometry:                   Particle-Particle
  57  * Calculate force/pot:        PotentialAndForce
  58  */
  59 void
  60 nb_kernel_ElecCoul_VdwNone_GeomP1P1_VF_sse2_single
  61                     (t_nblist                    * gmx_restrict       nlist,
  62                      rvec                        * gmx_restrict          xx,
  63                      rvec                        * gmx_restrict          ff,
  64                      t_forcerec                  * gmx_restrict          fr,
  65                      t_mdatoms                   * gmx_restrict     mdatoms,
  66                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
  67                      t_nrnb                      * gmx_restrict        nrnb)
  68 {
  69     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
  70      * just 0 for non-waters.
  71      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
  72      * jnr indices corresponding to data put in the four positions in the SIMD register.
  73      */
  74     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
  75     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
  76     int              jnrA,jnrB,jnrC,jnrD;
  77     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
  78     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
  79     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  80     real             rcutoff_scalar;
  81     real             *shiftvec,*fshift,*x,*f;
  82     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
  83     real             scratch[4*DIM];
  84     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
  85     int              vdwioffset0;
  86     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  87     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
  88     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  89     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
  90     __m128           velec,felec,velecsum,facel,crf,krf,krf2;
  91     real             *charge;
  92     __m128           dummy_mask,cutoff_mask;
  93     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
  94     __m128           one     = _mm_set1_ps(1.0);
  95     __m128           two     = _mm_set1_ps(2.0);
  96     x                = xx[0];
  97     f                = ff[0];
  98
  99     nri              = nlist->nri;
 100     iinr             = nlist->iinr;
 101     jindex           = nlist->jindex;
 102     jjnr             = nlist->jjnr;
 103     shiftidx         = nlist->shift;
 104     gid              = nlist->gid;
 105     shiftvec         = fr->shift_vec[0];
 106     fshift           = fr->fshift[0];
 107     facel            = _mm_set1_ps(fr->epsfac);
 108     charge           = mdatoms->chargeA;
 109
 110     /* Avoid stupid compiler warnings */
 111     jnrA = jnrB = jnrC = jnrD = 0;
 112     j_coord_offsetA = 0;
 113     j_coord_offsetB = 0;
 114     j_coord_offsetC = 0;
 115     j_coord_offsetD = 0;
 116
 117     outeriter        = 0;
 118     inneriter        = 0;
 119
 120     for(iidx=0;iidx<4*DIM;iidx++)
 121     {
 122         scratch[iidx] = 0.0;
 123     }
 124
 125     /* Start outer loop over neighborlists */
 126     for(iidx=0; iidx<nri; iidx++)
 127     {
 128         /* Load shift vector for this list */
 129         i_shift_offset   = DIM*shiftidx[iidx];
 130
 131         /* Load limits for loop over neighbors */
 132         j_index_start    = jindex[iidx];
 133         j_index_end      = jindex[iidx+1];
 134
 135         /* Get outer coordinate index */
 136         inr              = iinr[iidx];
 137         i_coord_offset   = DIM*inr;
 138
 139         /* Load i particle coords and add shift vector */
 140         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 141
 142         fix0             = _mm_setzero_ps();
 143         fiy0             = _mm_setzero_ps();
 144         fiz0             = _mm_setzero_ps();
 145
 146         /* Load parameters for i particles */
 147         iq0              = _mm_mul_ps(facel,_mm_load1_ps(charge+inr+0));
 148
 149         /* Reset potential sums */
 150         velecsum         = _mm_setzero_ps();
 151
 152         /* Start inner kernel loop */
 153         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
 154         {
 155
 156             /* Get j neighbor index, and coordinate index */
 157             jnrA             = jjnr[jidx];
 158             jnrB             = jjnr[jidx+1];
 159             jnrC             = jjnr[jidx+2];
 160             jnrD             = jjnr[jidx+3];
 161             j_coord_offsetA  = DIM*jnrA;
 162             j_coord_offsetB  = DIM*jnrB;
 163             j_coord_offsetC  = DIM*jnrC;
 164             j_coord_offsetD  = DIM*jnrD;
 165
 166             /* load j atom coordinates */
 167             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 168                                               x+j_coord_offsetC,x+j_coord_offsetD,
 169                                               &jx0,&jy0,&jz0);
 170
 171             /* Calculate displacement vector */
 172             dx00             = _mm_sub_ps(ix0,jx0);
 173             dy00             = _mm_sub_ps(iy0,jy0);
 174             dz00             = _mm_sub_ps(iz0,jz0);
 175
 176             /* Calculate squared distance and things based on it */
 177             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 178
 179             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 180
 181             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
 182
 183             /* Load parameters for j particles */
 184             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 185                                                               charge+jnrC+0,charge+jnrD+0);
 186
 187             /**************************
 188              * CALCULATE INTERACTIONS *
 189              **************************/
 190
 191             /* Compute parameters for interactions between i and j atoms */
 192             qq00             = _mm_mul_ps(iq0,jq0);
 193
 194             /* COULOMB ELECTROSTATICS */
 195             velec            = _mm_mul_ps(qq00,rinv00);
 196             felec            = _mm_mul_ps(velec,rinvsq00);
 197
 198             /* Update potential sum for this i atom from the interaction with this j atom. */
 199             velecsum         = _mm_add_ps(velecsum,velec);
 200
 201             fscal            = felec;
 202
 203             /* Calculate temporary vectorial force */
 204             tx               = _mm_mul_ps(fscal,dx00);
 205             ty               = _mm_mul_ps(fscal,dy00);
 206             tz               = _mm_mul_ps(fscal,dz00);
 207
 208             /* Update vectorial force */
 209             fix0             = _mm_add_ps(fix0,tx);
 210             fiy0             = _mm_add_ps(fiy0,ty);
 211             fiz0             = _mm_add_ps(fiz0,tz);
 212
 213             fjptrA             = f+j_coord_offsetA;
 214             fjptrB             = f+j_coord_offsetB;
 215             fjptrC             = f+j_coord_offsetC;
 216             fjptrD             = f+j_coord_offsetD;
 217             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 218
 219             /* Inner loop uses 28 flops */
 220         }
 221
 222         if(jidx<j_index_end)
 223         {
 224
 225             /* Get j neighbor index, and coordinate index */
 226             jnrlistA         = jjnr[jidx];
 227             jnrlistB         = jjnr[jidx+1];
 228             jnrlistC         = jjnr[jidx+2];
 229             jnrlistD         = jjnr[jidx+3];
 230             /* Sign of each element will be negative for non-real atoms.
 231              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
 232              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
 233              */
 234             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
 235             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
 236             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
 237             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
 238             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
 239             j_coord_offsetA  = DIM*jnrA;
 240             j_coord_offsetB  = DIM*jnrB;
 241             j_coord_offsetC  = DIM*jnrC;
 242             j_coord_offsetD  = DIM*jnrD;
 243
 244             /* load j atom coordinates */
 245             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 246                                               x+j_coord_offsetC,x+j_coord_offsetD,
 247                                               &jx0,&jy0,&jz0);
 248
 249             /* Calculate displacement vector */
 250             dx00             = _mm_sub_ps(ix0,jx0);
 251             dy00             = _mm_sub_ps(iy0,jy0);
 252             dz00             = _mm_sub_ps(iz0,jz0);
 253
 254             /* Calculate squared distance and things based on it */
 255             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 256
 257             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 258
 259             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
 260
 261             /* Load parameters for j particles */
 262             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 263                                                               charge+jnrC+0,charge+jnrD+0);
 264
 265             /**************************
 266              * CALCULATE INTERACTIONS *
 267              **************************/
 268
 269             /* Compute parameters for interactions between i and j atoms */
 270             qq00             = _mm_mul_ps(iq0,jq0);
 271
 272             /* COULOMB ELECTROSTATICS */
 273             velec            = _mm_mul_ps(qq00,rinv00);
 274             felec            = _mm_mul_ps(velec,rinvsq00);
 275
 276             /* Update potential sum for this i atom from the interaction with this j atom. */
 277             velec            = _mm_andnot_ps(dummy_mask,velec);
 278             velecsum         = _mm_add_ps(velecsum,velec);
 279
 280             fscal            = felec;
 281
 282             fscal            = _mm_andnot_ps(dummy_mask,fscal);
 283
 284             /* Calculate temporary vectorial force */
 285             tx               = _mm_mul_ps(fscal,dx00);
 286             ty               = _mm_mul_ps(fscal,dy00);
 287             tz               = _mm_mul_ps(fscal,dz00);
 288
 289             /* Update vectorial force */
 290             fix0             = _mm_add_ps(fix0,tx);
 291             fiy0             = _mm_add_ps(fiy0,ty);
 292             fiz0             = _mm_add_ps(fiz0,tz);
 293
 294             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
 295             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
 296             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
 297             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
 298             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 299
 300             /* Inner loop uses 28 flops */
 301         }
 302
 303         /* End of innermost loop */
 304
 305         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
 306                                               f+i_coord_offset,fshift+i_shift_offset);
 307
 308         ggid                        = gid[iidx];
 309         /* Update potential energies */
 310         gmx_mm_update_1pot_ps(velecsum,kernel_data->energygrp_elec+ggid);
 311
 312         /* Increment number of inner iterations */
 313         inneriter                  += j_index_end - j_index_start;
 314
 315         /* Outer loop uses 8 flops */
 316     }
 317
 318     /* Increment number of outer iterations */
 319     outeriter        += nri;
 320
 321     /* Update outer/inner flops */
 322
 323     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VF,outeriter*8 + inneriter*28);
 324 }
 325 /*
 326  * Gromacs nonbonded kernel:   nb_kernel_ElecCoul_VdwNone_GeomP1P1_F_sse2_single
 327  * Electrostatics interaction: Coulomb
 328  * VdW interaction:            None
 329  * Geometry:                   Particle-Particle
 330  * Calculate force/pot:        Force
 331  */
 332 void
 333 nb_kernel_ElecCoul_VdwNone_GeomP1P1_F_sse2_single
 334                     (t_nblist                    * gmx_restrict       nlist,
 335                      rvec                        * gmx_restrict          xx,
 336                      rvec                        * gmx_restrict          ff,
 337                      t_forcerec                  * gmx_restrict          fr,
 338                      t_mdatoms                   * gmx_restrict     mdatoms,
 339                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 340                      t_nrnb                      * gmx_restrict        nrnb)
 341 {
 342     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
 343      * just 0 for non-waters.
 344      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
 345      * jnr indices corresponding to data put in the four positions in the SIMD register.
 346      */
 347     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
 348     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
 349     int              jnrA,jnrB,jnrC,jnrD;
 350     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
 351     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
 352     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 353     real             rcutoff_scalar;
 354     real             *shiftvec,*fshift,*x,*f;
 355     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
 356     real             scratch[4*DIM];
 357     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
 358     int              vdwioffset0;
 359     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 360     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
 361     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 362     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
 363     __m128           velec,felec,velecsum,facel,crf,krf,krf2;
 364     real             *charge;
 365     __m128           dummy_mask,cutoff_mask;
 366     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
 367     __m128           one     = _mm_set1_ps(1.0);
 368     __m128           two     = _mm_set1_ps(2.0);
 369     x                = xx[0];
 370     f                = ff[0];
 371
 372     nri              = nlist->nri;
 373     iinr             = nlist->iinr;
 374     jindex           = nlist->jindex;
 375     jjnr             = nlist->jjnr;
 376     shiftidx         = nlist->shift;
 377     gid              = nlist->gid;
 378     shiftvec         = fr->shift_vec[0];
 379     fshift           = fr->fshift[0];
 380     facel            = _mm_set1_ps(fr->epsfac);
 381     charge           = mdatoms->chargeA;
 382
 383     /* Avoid stupid compiler warnings */
 384     jnrA = jnrB = jnrC = jnrD = 0;
 385     j_coord_offsetA = 0;
 386     j_coord_offsetB = 0;
 387     j_coord_offsetC = 0;
 388     j_coord_offsetD = 0;
 389
 390     outeriter        = 0;
 391     inneriter        = 0;
 392
 393     for(iidx=0;iidx<4*DIM;iidx++)
 394     {
 395         scratch[iidx] = 0.0;
 396     }
 397
 398     /* Start outer loop over neighborlists */
 399     for(iidx=0; iidx<nri; iidx++)
 400     {
 401         /* Load shift vector for this list */
 402         i_shift_offset   = DIM*shiftidx[iidx];
 403
 404         /* Load limits for loop over neighbors */
 405         j_index_start    = jindex[iidx];
 406         j_index_end      = jindex[iidx+1];
 407
 408         /* Get outer coordinate index */
 409         inr              = iinr[iidx];
 410         i_coord_offset   = DIM*inr;
 411
 412         /* Load i particle coords and add shift vector */
 413         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 414
 415         fix0             = _mm_setzero_ps();
 416         fiy0             = _mm_setzero_ps();
 417         fiz0             = _mm_setzero_ps();
 418
 419         /* Load parameters for i particles */
 420         iq0              = _mm_mul_ps(facel,_mm_load1_ps(charge+inr+0));
 421
 422         /* Start inner kernel loop */
 423         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
 424         {
 425
 426             /* Get j neighbor index, and coordinate index */
 427             jnrA             = jjnr[jidx];
 428             jnrB             = jjnr[jidx+1];
 429             jnrC             = jjnr[jidx+2];
 430             jnrD             = jjnr[jidx+3];
 431             j_coord_offsetA  = DIM*jnrA;
 432             j_coord_offsetB  = DIM*jnrB;
 433             j_coord_offsetC  = DIM*jnrC;
 434             j_coord_offsetD  = DIM*jnrD;
 435
 436             /* load j atom coordinates */
 437             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 438                                               x+j_coord_offsetC,x+j_coord_offsetD,
 439                                               &jx0,&jy0,&jz0);
 440
 441             /* Calculate displacement vector */
 442             dx00             = _mm_sub_ps(ix0,jx0);
 443             dy00             = _mm_sub_ps(iy0,jy0);
 444             dz00             = _mm_sub_ps(iz0,jz0);
 445
 446             /* Calculate squared distance and things based on it */
 447             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 448
 449             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 450
 451             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
 452
 453             /* Load parameters for j particles */
 454             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 455                                                               charge+jnrC+0,charge+jnrD+0);
 456
 457             /**************************
 458              * CALCULATE INTERACTIONS *
 459              **************************/
 460
 461             /* Compute parameters for interactions between i and j atoms */
 462             qq00             = _mm_mul_ps(iq0,jq0);
 463
 464             /* COULOMB ELECTROSTATICS */
 465             velec            = _mm_mul_ps(qq00,rinv00);
 466             felec            = _mm_mul_ps(velec,rinvsq00);
 467
 468             fscal            = felec;
 469
 470             /* Calculate temporary vectorial force */
 471             tx               = _mm_mul_ps(fscal,dx00);
 472             ty               = _mm_mul_ps(fscal,dy00);
 473             tz               = _mm_mul_ps(fscal,dz00);
 474
 475             /* Update vectorial force */
 476             fix0             = _mm_add_ps(fix0,tx);
 477             fiy0             = _mm_add_ps(fiy0,ty);
 478             fiz0             = _mm_add_ps(fiz0,tz);
 479
 480             fjptrA             = f+j_coord_offsetA;
 481             fjptrB             = f+j_coord_offsetB;
 482             fjptrC             = f+j_coord_offsetC;
 483             fjptrD             = f+j_coord_offsetD;
 484             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 485
 486             /* Inner loop uses 27 flops */
 487         }
 488
 489         if(jidx<j_index_end)
 490         {
 491
 492             /* Get j neighbor index, and coordinate index */
 493             jnrlistA         = jjnr[jidx];
 494             jnrlistB         = jjnr[jidx+1];
 495             jnrlistC         = jjnr[jidx+2];
 496             jnrlistD         = jjnr[jidx+3];
 497             /* Sign of each element will be negative for non-real atoms.
 498              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
 499              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
 500              */
 501             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
 502             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
 503             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
 504             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
 505             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
 506             j_coord_offsetA  = DIM*jnrA;
 507             j_coord_offsetB  = DIM*jnrB;
 508             j_coord_offsetC  = DIM*jnrC;
 509             j_coord_offsetD  = DIM*jnrD;
 510
 511             /* load j atom coordinates */
 512             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 513                                               x+j_coord_offsetC,x+j_coord_offsetD,
 514                                               &jx0,&jy0,&jz0);
 515
 516             /* Calculate displacement vector */
 517             dx00             = _mm_sub_ps(ix0,jx0);
 518             dy00             = _mm_sub_ps(iy0,jy0);
 519             dz00             = _mm_sub_ps(iz0,jz0);
 520
 521             /* Calculate squared distance and things based on it */
 522             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 523
 524             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 525
 526             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
 527
 528             /* Load parameters for j particles */
 529             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 530                                                               charge+jnrC+0,charge+jnrD+0);
 531
 532             /**************************
 533              * CALCULATE INTERACTIONS *
 534              **************************/
 535
 536             /* Compute parameters for interactions between i and j atoms */
 537             qq00             = _mm_mul_ps(iq0,jq0);
 538
 539             /* COULOMB ELECTROSTATICS */
 540             velec            = _mm_mul_ps(qq00,rinv00);
 541             felec            = _mm_mul_ps(velec,rinvsq00);
 542
 543             fscal            = felec;
 544
 545             fscal            = _mm_andnot_ps(dummy_mask,fscal);
 546
 547             /* Calculate temporary vectorial force */
 548             tx               = _mm_mul_ps(fscal,dx00);
 549             ty               = _mm_mul_ps(fscal,dy00);
 550             tz               = _mm_mul_ps(fscal,dz00);
 551
 552             /* Update vectorial force */
 553             fix0             = _mm_add_ps(fix0,tx);
 554             fiy0             = _mm_add_ps(fiy0,ty);
 555             fiz0             = _mm_add_ps(fiz0,tz);
 556
 557             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
 558             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
 559             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
 560             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
 561             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 562
 563             /* Inner loop uses 27 flops */
 564         }
 565
 566         /* End of innermost loop */
 567
 568         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
 569                                               f+i_coord_offset,fshift+i_shift_offset);
 570
 571         /* Increment number of inner iterations */
 572         inneriter                  += j_index_end - j_index_start;
 573
 574         /* Outer loop uses 7 flops */
 575     }
 576
 577     /* Increment number of outer iterations */
 578     outeriter        += nri;
 579
 580     /* Update outer/inner flops */
 581
 582     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_F,outeriter*7 + inneriter*27);
 583 }