src/gromacs/gmxlib/nonbonded/nb_kernel_avx_256_single/nb_kernel_ElecRF_VdwNone_GeomP1P1_avx_256_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
  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 avx_256_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_avx_256_single.h"
  50 #include "kernelutil_x86_avx_256_single.h"
  51
  52 /*
  53  * Gromacs nonbonded kernel:   nb_kernel_ElecRF_VdwNone_GeomP1P1_VF_avx_256_single
  54  * Electrostatics interaction: ReactionField
  55  * VdW interaction:            None
  56  * Geometry:                   Particle-Particle
  57  * Calculate force/pot:        PotentialAndForce
  58  */
  59 void
  60 nb_kernel_ElecRF_VdwNone_GeomP1P1_VF_avx_256_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,E,F,G,H refer to j loop unrolling done with AVX, e.g. for the eight 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              jnrE,jnrF,jnrG,jnrH;
  78     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
  79     int              jnrlistE,jnrlistF,jnrlistG,jnrlistH;
  80     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
  81     int              j_coord_offsetE,j_coord_offsetF,j_coord_offsetG,j_coord_offsetH;
  82     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  83     real             rcutoff_scalar;
  84     real             *shiftvec,*fshift,*x,*f;
  85     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD,*fjptrE,*fjptrF,*fjptrG,*fjptrH;
  86     real             scratch[4*DIM];
  87     __m256           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
  88     real *           vdwioffsetptr0;
  89     __m256           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  90     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D,vdwjidx0E,vdwjidx0F,vdwjidx0G,vdwjidx0H;
  91     __m256           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  92     __m256           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
  93     __m256           velec,felec,velecsum,facel,crf,krf,krf2;
  94     real             *charge;
  95     __m256           dummy_mask,cutoff_mask;
  96     __m256           signbit = _mm256_castsi256_ps( _mm256_set1_epi32(0x80000000) );
  97     __m256           one     = _mm256_set1_ps(1.0);
  98     __m256           two     = _mm256_set1_ps(2.0);
  99     x                = xx[0];
 100     f                = ff[0];
 101
 102     nri              = nlist->nri;
 103     iinr             = nlist->iinr;
 104     jindex           = nlist->jindex;
 105     jjnr             = nlist->jjnr;
 106     shiftidx         = nlist->shift;
 107     gid              = nlist->gid;
 108     shiftvec         = fr->shift_vec[0];
 109     fshift           = fr->fshift[0];
 110     facel            = _mm256_set1_ps(fr->epsfac);
 111     charge           = mdatoms->chargeA;
 112     krf              = _mm256_set1_ps(fr->ic->k_rf);
 113     krf2             = _mm256_set1_ps(fr->ic->k_rf*2.0);
 114     crf              = _mm256_set1_ps(fr->ic->c_rf);
 115
 116     /* Avoid stupid compiler warnings */
 117     jnrA = jnrB = jnrC = jnrD = jnrE = jnrF = jnrG = jnrH = 0;
 118     j_coord_offsetA = 0;
 119     j_coord_offsetB = 0;
 120     j_coord_offsetC = 0;
 121     j_coord_offsetD = 0;
 122     j_coord_offsetE = 0;
 123     j_coord_offsetF = 0;
 124     j_coord_offsetG = 0;
 125     j_coord_offsetH = 0;
 126
 127     outeriter        = 0;
 128     inneriter        = 0;
 129
 130     for(iidx=0;iidx<4*DIM;iidx++)
 131     {
 132         scratch[iidx] = 0.0;
 133     }
 134
 135     /* Start outer loop over neighborlists */
 136     for(iidx=0; iidx<nri; iidx++)
 137     {
 138         /* Load shift vector for this list */
 139         i_shift_offset   = DIM*shiftidx[iidx];
 140
 141         /* Load limits for loop over neighbors */
 142         j_index_start    = jindex[iidx];
 143         j_index_end      = jindex[iidx+1];
 144
 145         /* Get outer coordinate index */
 146         inr              = iinr[iidx];
 147         i_coord_offset   = DIM*inr;
 148
 149         /* Load i particle coords and add shift vector */
 150         gmx_mm256_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 151
 152         fix0             = _mm256_setzero_ps();
 153         fiy0             = _mm256_setzero_ps();
 154         fiz0             = _mm256_setzero_ps();
 155
 156         /* Load parameters for i particles */
 157         iq0              = _mm256_mul_ps(facel,_mm256_set1_ps(charge[inr+0]));
 158
 159         /* Reset potential sums */
 160         velecsum         = _mm256_setzero_ps();
 161
 162         /* Start inner kernel loop */
 163         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+7]>=0; jidx+=8)
 164         {
 165
 166             /* Get j neighbor index, and coordinate index */
 167             jnrA             = jjnr[jidx];
 168             jnrB             = jjnr[jidx+1];
 169             jnrC             = jjnr[jidx+2];
 170             jnrD             = jjnr[jidx+3];
 171             jnrE             = jjnr[jidx+4];
 172             jnrF             = jjnr[jidx+5];
 173             jnrG             = jjnr[jidx+6];
 174             jnrH             = jjnr[jidx+7];
 175             j_coord_offsetA  = DIM*jnrA;
 176             j_coord_offsetB  = DIM*jnrB;
 177             j_coord_offsetC  = DIM*jnrC;
 178             j_coord_offsetD  = DIM*jnrD;
 179             j_coord_offsetE  = DIM*jnrE;
 180             j_coord_offsetF  = DIM*jnrF;
 181             j_coord_offsetG  = DIM*jnrG;
 182             j_coord_offsetH  = DIM*jnrH;
 183
 184             /* load j atom coordinates */
 185             gmx_mm256_load_1rvec_8ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 186                                                  x+j_coord_offsetC,x+j_coord_offsetD,
 187                                                  x+j_coord_offsetE,x+j_coord_offsetF,
 188                                                  x+j_coord_offsetG,x+j_coord_offsetH,
 189                                                  &jx0,&jy0,&jz0);
 190
 191             /* Calculate displacement vector */
 192             dx00             = _mm256_sub_ps(ix0,jx0);
 193             dy00             = _mm256_sub_ps(iy0,jy0);
 194             dz00             = _mm256_sub_ps(iz0,jz0);
 195
 196             /* Calculate squared distance and things based on it */
 197             rsq00            = gmx_mm256_calc_rsq_ps(dx00,dy00,dz00);
 198
 199             rinv00           = gmx_mm256_invsqrt_ps(rsq00);
 200
 201             rinvsq00         = _mm256_mul_ps(rinv00,rinv00);
 202
 203             /* Load parameters for j particles */
 204             jq0              = gmx_mm256_load_8real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 205                                                                  charge+jnrC+0,charge+jnrD+0,
 206                                                                  charge+jnrE+0,charge+jnrF+0,
 207                                                                  charge+jnrG+0,charge+jnrH+0);
 208
 209             /**************************
 210              * CALCULATE INTERACTIONS *
 211              **************************/
 212
 213             /* Compute parameters for interactions between i and j atoms */
 214             qq00             = _mm256_mul_ps(iq0,jq0);
 215
 216             /* REACTION-FIELD ELECTROSTATICS */
 217             velec            = _mm256_mul_ps(qq00,_mm256_sub_ps(_mm256_add_ps(rinv00,_mm256_mul_ps(krf,rsq00)),crf));
 218             felec            = _mm256_mul_ps(qq00,_mm256_sub_ps(_mm256_mul_ps(rinv00,rinvsq00),krf2));
 219
 220             /* Update potential sum for this i atom from the interaction with this j atom. */
 221             velecsum         = _mm256_add_ps(velecsum,velec);
 222
 223             fscal            = felec;
 224
 225             /* Calculate temporary vectorial force */
 226             tx               = _mm256_mul_ps(fscal,dx00);
 227             ty               = _mm256_mul_ps(fscal,dy00);
 228             tz               = _mm256_mul_ps(fscal,dz00);
 229
 230             /* Update vectorial force */
 231             fix0             = _mm256_add_ps(fix0,tx);
 232             fiy0             = _mm256_add_ps(fiy0,ty);
 233             fiz0             = _mm256_add_ps(fiz0,tz);
 234
 235             fjptrA             = f+j_coord_offsetA;
 236             fjptrB             = f+j_coord_offsetB;
 237             fjptrC             = f+j_coord_offsetC;
 238             fjptrD             = f+j_coord_offsetD;
 239             fjptrE             = f+j_coord_offsetE;
 240             fjptrF             = f+j_coord_offsetF;
 241             fjptrG             = f+j_coord_offsetG;
 242             fjptrH             = f+j_coord_offsetH;
 243             gmx_mm256_decrement_1rvec_8ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,fjptrE,fjptrF,fjptrG,fjptrH,tx,ty,tz);
 244
 245             /* Inner loop uses 32 flops */
 246         }
 247
 248         if(jidx<j_index_end)
 249         {
 250
 251             /* Get j neighbor index, and coordinate index */
 252             jnrlistA         = jjnr[jidx];
 253             jnrlistB         = jjnr[jidx+1];
 254             jnrlistC         = jjnr[jidx+2];
 255             jnrlistD         = jjnr[jidx+3];
 256             jnrlistE         = jjnr[jidx+4];
 257             jnrlistF         = jjnr[jidx+5];
 258             jnrlistG         = jjnr[jidx+6];
 259             jnrlistH         = jjnr[jidx+7];
 260             /* Sign of each element will be negative for non-real atoms.
 261              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
 262              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
 263              */
 264             dummy_mask = gmx_mm256_set_m128(gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx+4)),_mm_setzero_si128())),
 265                                             gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128())));
 266
 267             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
 268             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
 269             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
 270             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
 271             jnrE       = (jnrlistE>=0) ? jnrlistE : 0;
 272             jnrF       = (jnrlistF>=0) ? jnrlistF : 0;
 273             jnrG       = (jnrlistG>=0) ? jnrlistG : 0;
 274             jnrH       = (jnrlistH>=0) ? jnrlistH : 0;
 275             j_coord_offsetA  = DIM*jnrA;
 276             j_coord_offsetB  = DIM*jnrB;
 277             j_coord_offsetC  = DIM*jnrC;
 278             j_coord_offsetD  = DIM*jnrD;
 279             j_coord_offsetE  = DIM*jnrE;
 280             j_coord_offsetF  = DIM*jnrF;
 281             j_coord_offsetG  = DIM*jnrG;
 282             j_coord_offsetH  = DIM*jnrH;
 283
 284             /* load j atom coordinates */
 285             gmx_mm256_load_1rvec_8ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 286                                                  x+j_coord_offsetC,x+j_coord_offsetD,
 287                                                  x+j_coord_offsetE,x+j_coord_offsetF,
 288                                                  x+j_coord_offsetG,x+j_coord_offsetH,
 289                                                  &jx0,&jy0,&jz0);
 290
 291             /* Calculate displacement vector */
 292             dx00             = _mm256_sub_ps(ix0,jx0);
 293             dy00             = _mm256_sub_ps(iy0,jy0);
 294             dz00             = _mm256_sub_ps(iz0,jz0);
 295
 296             /* Calculate squared distance and things based on it */
 297             rsq00            = gmx_mm256_calc_rsq_ps(dx00,dy00,dz00);
 298
 299             rinv00           = gmx_mm256_invsqrt_ps(rsq00);
 300
 301             rinvsq00         = _mm256_mul_ps(rinv00,rinv00);
 302
 303             /* Load parameters for j particles */
 304             jq0              = gmx_mm256_load_8real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 305                                                                  charge+jnrC+0,charge+jnrD+0,
 306                                                                  charge+jnrE+0,charge+jnrF+0,
 307                                                                  charge+jnrG+0,charge+jnrH+0);
 308
 309             /**************************
 310              * CALCULATE INTERACTIONS *
 311              **************************/
 312
 313             /* Compute parameters for interactions between i and j atoms */
 314             qq00             = _mm256_mul_ps(iq0,jq0);
 315
 316             /* REACTION-FIELD ELECTROSTATICS */
 317             velec            = _mm256_mul_ps(qq00,_mm256_sub_ps(_mm256_add_ps(rinv00,_mm256_mul_ps(krf,rsq00)),crf));
 318             felec            = _mm256_mul_ps(qq00,_mm256_sub_ps(_mm256_mul_ps(rinv00,rinvsq00),krf2));
 319
 320             /* Update potential sum for this i atom from the interaction with this j atom. */
 321             velec            = _mm256_andnot_ps(dummy_mask,velec);
 322             velecsum         = _mm256_add_ps(velecsum,velec);
 323
 324             fscal            = felec;
 325
 326             fscal            = _mm256_andnot_ps(dummy_mask,fscal);
 327
 328             /* Calculate temporary vectorial force */
 329             tx               = _mm256_mul_ps(fscal,dx00);
 330             ty               = _mm256_mul_ps(fscal,dy00);
 331             tz               = _mm256_mul_ps(fscal,dz00);
 332
 333             /* Update vectorial force */
 334             fix0             = _mm256_add_ps(fix0,tx);
 335             fiy0             = _mm256_add_ps(fiy0,ty);
 336             fiz0             = _mm256_add_ps(fiz0,tz);
 337
 338             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
 339             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
 340             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
 341             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
 342             fjptrE             = (jnrlistE>=0) ? f+j_coord_offsetE : scratch;
 343             fjptrF             = (jnrlistF>=0) ? f+j_coord_offsetF : scratch;
 344             fjptrG             = (jnrlistG>=0) ? f+j_coord_offsetG : scratch;
 345             fjptrH             = (jnrlistH>=0) ? f+j_coord_offsetH : scratch;
 346             gmx_mm256_decrement_1rvec_8ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,fjptrE,fjptrF,fjptrG,fjptrH,tx,ty,tz);
 347
 348             /* Inner loop uses 32 flops */
 349         }
 350
 351         /* End of innermost loop */
 352
 353         gmx_mm256_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
 354                                                  f+i_coord_offset,fshift+i_shift_offset);
 355
 356         ggid                        = gid[iidx];
 357         /* Update potential energies */
 358         gmx_mm256_update_1pot_ps(velecsum,kernel_data->energygrp_elec+ggid);
 359
 360         /* Increment number of inner iterations */
 361         inneriter                  += j_index_end - j_index_start;
 362
 363         /* Outer loop uses 8 flops */
 364     }
 365
 366     /* Increment number of outer iterations */
 367     outeriter        += nri;
 368
 369     /* Update outer/inner flops */
 370
 371     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VF,outeriter*8 + inneriter*32);
 372 }
 373 /*
 374  * Gromacs nonbonded kernel:   nb_kernel_ElecRF_VdwNone_GeomP1P1_F_avx_256_single
 375  * Electrostatics interaction: ReactionField
 376  * VdW interaction:            None
 377  * Geometry:                   Particle-Particle
 378  * Calculate force/pot:        Force
 379  */
 380 void
 381 nb_kernel_ElecRF_VdwNone_GeomP1P1_F_avx_256_single
 382                     (t_nblist                    * gmx_restrict       nlist,
 383                      rvec                        * gmx_restrict          xx,
 384                      rvec                        * gmx_restrict          ff,
 385                      t_forcerec                  * gmx_restrict          fr,
 386                      t_mdatoms                   * gmx_restrict     mdatoms,
 387                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 388                      t_nrnb                      * gmx_restrict        nrnb)
 389 {
 390     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
 391      * just 0 for non-waters.
 392      * Suffixes A,B,C,D,E,F,G,H refer to j loop unrolling done with AVX, e.g. for the eight different
 393      * jnr indices corresponding to data put in the four positions in the SIMD register.
 394      */
 395     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
 396     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
 397     int              jnrA,jnrB,jnrC,jnrD;
 398     int              jnrE,jnrF,jnrG,jnrH;
 399     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
 400     int              jnrlistE,jnrlistF,jnrlistG,jnrlistH;
 401     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
 402     int              j_coord_offsetE,j_coord_offsetF,j_coord_offsetG,j_coord_offsetH;
 403     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 404     real             rcutoff_scalar;
 405     real             *shiftvec,*fshift,*x,*f;
 406     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD,*fjptrE,*fjptrF,*fjptrG,*fjptrH;
 407     real             scratch[4*DIM];
 408     __m256           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
 409     real *           vdwioffsetptr0;
 410     __m256           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 411     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D,vdwjidx0E,vdwjidx0F,vdwjidx0G,vdwjidx0H;
 412     __m256           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 413     __m256           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
 414     __m256           velec,felec,velecsum,facel,crf,krf,krf2;
 415     real             *charge;
 416     __m256           dummy_mask,cutoff_mask;
 417     __m256           signbit = _mm256_castsi256_ps( _mm256_set1_epi32(0x80000000) );
 418     __m256           one     = _mm256_set1_ps(1.0);
 419     __m256           two     = _mm256_set1_ps(2.0);
 420     x                = xx[0];
 421     f                = ff[0];
 422
 423     nri              = nlist->nri;
 424     iinr             = nlist->iinr;
 425     jindex           = nlist->jindex;
 426     jjnr             = nlist->jjnr;
 427     shiftidx         = nlist->shift;
 428     gid              = nlist->gid;
 429     shiftvec         = fr->shift_vec[0];
 430     fshift           = fr->fshift[0];
 431     facel            = _mm256_set1_ps(fr->epsfac);
 432     charge           = mdatoms->chargeA;
 433     krf              = _mm256_set1_ps(fr->ic->k_rf);
 434     krf2             = _mm256_set1_ps(fr->ic->k_rf*2.0);
 435     crf              = _mm256_set1_ps(fr->ic->c_rf);
 436
 437     /* Avoid stupid compiler warnings */
 438     jnrA = jnrB = jnrC = jnrD = jnrE = jnrF = jnrG = jnrH = 0;
 439     j_coord_offsetA = 0;
 440     j_coord_offsetB = 0;
 441     j_coord_offsetC = 0;
 442     j_coord_offsetD = 0;
 443     j_coord_offsetE = 0;
 444     j_coord_offsetF = 0;
 445     j_coord_offsetG = 0;
 446     j_coord_offsetH = 0;
 447
 448     outeriter        = 0;
 449     inneriter        = 0;
 450
 451     for(iidx=0;iidx<4*DIM;iidx++)
 452     {
 453         scratch[iidx] = 0.0;
 454     }
 455
 456     /* Start outer loop over neighborlists */
 457     for(iidx=0; iidx<nri; iidx++)
 458     {
 459         /* Load shift vector for this list */
 460         i_shift_offset   = DIM*shiftidx[iidx];
 461
 462         /* Load limits for loop over neighbors */
 463         j_index_start    = jindex[iidx];
 464         j_index_end      = jindex[iidx+1];
 465
 466         /* Get outer coordinate index */
 467         inr              = iinr[iidx];
 468         i_coord_offset   = DIM*inr;
 469
 470         /* Load i particle coords and add shift vector */
 471         gmx_mm256_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 472
 473         fix0             = _mm256_setzero_ps();
 474         fiy0             = _mm256_setzero_ps();
 475         fiz0             = _mm256_setzero_ps();
 476
 477         /* Load parameters for i particles */
 478         iq0              = _mm256_mul_ps(facel,_mm256_set1_ps(charge[inr+0]));
 479
 480         /* Start inner kernel loop */
 481         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+7]>=0; jidx+=8)
 482         {
 483
 484             /* Get j neighbor index, and coordinate index */
 485             jnrA             = jjnr[jidx];
 486             jnrB             = jjnr[jidx+1];
 487             jnrC             = jjnr[jidx+2];
 488             jnrD             = jjnr[jidx+3];
 489             jnrE             = jjnr[jidx+4];
 490             jnrF             = jjnr[jidx+5];
 491             jnrG             = jjnr[jidx+6];
 492             jnrH             = jjnr[jidx+7];
 493             j_coord_offsetA  = DIM*jnrA;
 494             j_coord_offsetB  = DIM*jnrB;
 495             j_coord_offsetC  = DIM*jnrC;
 496             j_coord_offsetD  = DIM*jnrD;
 497             j_coord_offsetE  = DIM*jnrE;
 498             j_coord_offsetF  = DIM*jnrF;
 499             j_coord_offsetG  = DIM*jnrG;
 500             j_coord_offsetH  = DIM*jnrH;
 501
 502             /* load j atom coordinates */
 503             gmx_mm256_load_1rvec_8ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 504                                                  x+j_coord_offsetC,x+j_coord_offsetD,
 505                                                  x+j_coord_offsetE,x+j_coord_offsetF,
 506                                                  x+j_coord_offsetG,x+j_coord_offsetH,
 507                                                  &jx0,&jy0,&jz0);
 508
 509             /* Calculate displacement vector */
 510             dx00             = _mm256_sub_ps(ix0,jx0);
 511             dy00             = _mm256_sub_ps(iy0,jy0);
 512             dz00             = _mm256_sub_ps(iz0,jz0);
 513
 514             /* Calculate squared distance and things based on it */
 515             rsq00            = gmx_mm256_calc_rsq_ps(dx00,dy00,dz00);
 516
 517             rinv00           = gmx_mm256_invsqrt_ps(rsq00);
 518
 519             rinvsq00         = _mm256_mul_ps(rinv00,rinv00);
 520
 521             /* Load parameters for j particles */
 522             jq0              = gmx_mm256_load_8real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 523                                                                  charge+jnrC+0,charge+jnrD+0,
 524                                                                  charge+jnrE+0,charge+jnrF+0,
 525                                                                  charge+jnrG+0,charge+jnrH+0);
 526
 527             /**************************
 528              * CALCULATE INTERACTIONS *
 529              **************************/
 530
 531             /* Compute parameters for interactions between i and j atoms */
 532             qq00             = _mm256_mul_ps(iq0,jq0);
 533
 534             /* REACTION-FIELD ELECTROSTATICS */
 535             felec            = _mm256_mul_ps(qq00,_mm256_sub_ps(_mm256_mul_ps(rinv00,rinvsq00),krf2));
 536
 537             fscal            = felec;
 538
 539             /* Calculate temporary vectorial force */
 540             tx               = _mm256_mul_ps(fscal,dx00);
 541             ty               = _mm256_mul_ps(fscal,dy00);
 542             tz               = _mm256_mul_ps(fscal,dz00);
 543
 544             /* Update vectorial force */
 545             fix0             = _mm256_add_ps(fix0,tx);
 546             fiy0             = _mm256_add_ps(fiy0,ty);
 547             fiz0             = _mm256_add_ps(fiz0,tz);
 548
 549             fjptrA             = f+j_coord_offsetA;
 550             fjptrB             = f+j_coord_offsetB;
 551             fjptrC             = f+j_coord_offsetC;
 552             fjptrD             = f+j_coord_offsetD;
 553             fjptrE             = f+j_coord_offsetE;
 554             fjptrF             = f+j_coord_offsetF;
 555             fjptrG             = f+j_coord_offsetG;
 556             fjptrH             = f+j_coord_offsetH;
 557             gmx_mm256_decrement_1rvec_8ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,fjptrE,fjptrF,fjptrG,fjptrH,tx,ty,tz);
 558
 559             /* Inner loop uses 27 flops */
 560         }
 561
 562         if(jidx<j_index_end)
 563         {
 564
 565             /* Get j neighbor index, and coordinate index */
 566             jnrlistA         = jjnr[jidx];
 567             jnrlistB         = jjnr[jidx+1];
 568             jnrlistC         = jjnr[jidx+2];
 569             jnrlistD         = jjnr[jidx+3];
 570             jnrlistE         = jjnr[jidx+4];
 571             jnrlistF         = jjnr[jidx+5];
 572             jnrlistG         = jjnr[jidx+6];
 573             jnrlistH         = jjnr[jidx+7];
 574             /* Sign of each element will be negative for non-real atoms.
 575              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
 576              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
 577              */
 578             dummy_mask = gmx_mm256_set_m128(gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx+4)),_mm_setzero_si128())),
 579                                             gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128())));
 580
 581             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
 582             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
 583             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
 584             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
 585             jnrE       = (jnrlistE>=0) ? jnrlistE : 0;
 586             jnrF       = (jnrlistF>=0) ? jnrlistF : 0;
 587             jnrG       = (jnrlistG>=0) ? jnrlistG : 0;
 588             jnrH       = (jnrlistH>=0) ? jnrlistH : 0;
 589             j_coord_offsetA  = DIM*jnrA;
 590             j_coord_offsetB  = DIM*jnrB;
 591             j_coord_offsetC  = DIM*jnrC;
 592             j_coord_offsetD  = DIM*jnrD;
 593             j_coord_offsetE  = DIM*jnrE;
 594             j_coord_offsetF  = DIM*jnrF;
 595             j_coord_offsetG  = DIM*jnrG;
 596             j_coord_offsetH  = DIM*jnrH;
 597
 598             /* load j atom coordinates */
 599             gmx_mm256_load_1rvec_8ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 600                                                  x+j_coord_offsetC,x+j_coord_offsetD,
 601                                                  x+j_coord_offsetE,x+j_coord_offsetF,
 602                                                  x+j_coord_offsetG,x+j_coord_offsetH,
 603                                                  &jx0,&jy0,&jz0);
 604
 605             /* Calculate displacement vector */
 606             dx00             = _mm256_sub_ps(ix0,jx0);
 607             dy00             = _mm256_sub_ps(iy0,jy0);
 608             dz00             = _mm256_sub_ps(iz0,jz0);
 609
 610             /* Calculate squared distance and things based on it */
 611             rsq00            = gmx_mm256_calc_rsq_ps(dx00,dy00,dz00);
 612
 613             rinv00           = gmx_mm256_invsqrt_ps(rsq00);
 614
 615             rinvsq00         = _mm256_mul_ps(rinv00,rinv00);
 616
 617             /* Load parameters for j particles */
 618             jq0              = gmx_mm256_load_8real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 619                                                                  charge+jnrC+0,charge+jnrD+0,
 620                                                                  charge+jnrE+0,charge+jnrF+0,
 621                                                                  charge+jnrG+0,charge+jnrH+0);
 622
 623             /**************************
 624              * CALCULATE INTERACTIONS *
 625              **************************/
 626
 627             /* Compute parameters for interactions between i and j atoms */
 628             qq00             = _mm256_mul_ps(iq0,jq0);
 629
 630             /* REACTION-FIELD ELECTROSTATICS */
 631             felec            = _mm256_mul_ps(qq00,_mm256_sub_ps(_mm256_mul_ps(rinv00,rinvsq00),krf2));
 632
 633             fscal            = felec;
 634
 635             fscal            = _mm256_andnot_ps(dummy_mask,fscal);
 636
 637             /* Calculate temporary vectorial force */
 638             tx               = _mm256_mul_ps(fscal,dx00);
 639             ty               = _mm256_mul_ps(fscal,dy00);
 640             tz               = _mm256_mul_ps(fscal,dz00);
 641
 642             /* Update vectorial force */
 643             fix0             = _mm256_add_ps(fix0,tx);
 644             fiy0             = _mm256_add_ps(fiy0,ty);
 645             fiz0             = _mm256_add_ps(fiz0,tz);
 646
 647             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
 648             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
 649             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
 650             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
 651             fjptrE             = (jnrlistE>=0) ? f+j_coord_offsetE : scratch;
 652             fjptrF             = (jnrlistF>=0) ? f+j_coord_offsetF : scratch;
 653             fjptrG             = (jnrlistG>=0) ? f+j_coord_offsetG : scratch;
 654             fjptrH             = (jnrlistH>=0) ? f+j_coord_offsetH : scratch;
 655             gmx_mm256_decrement_1rvec_8ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,fjptrE,fjptrF,fjptrG,fjptrH,tx,ty,tz);
 656
 657             /* Inner loop uses 27 flops */
 658         }
 659
 660         /* End of innermost loop */
 661
 662         gmx_mm256_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
 663                                                  f+i_coord_offset,fshift+i_shift_offset);
 664
 665         /* Increment number of inner iterations */
 666         inneriter                  += j_index_end - j_index_start;
 667
 668         /* Outer loop uses 7 flops */
 669     }
 670
 671     /* Increment number of outer iterations */
 672     outeriter        += nri;
 673
 674     /* Update outer/inner flops */
 675
 676     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_F,outeriter*7 + inneriter*27);
 677 }