src/gromacs/gmxlib/nonbonded/nb_kernel_avx_256_double/nb_kernel_ElecGB_VdwNone_GeomP1P1_avx_256_double.c

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2012,2013,2014, by the GROMACS development team, led by
   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
   6  * and including many others, as listed in the AUTHORS file in the
   7  * top-level source directory and at http://www.gromacs.org.
   8  *
   9  * GROMACS is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1
  12  * of the License, or (at your option) any later version.
  13  *
  14  * GROMACS is distributed in the hope that it will be useful,
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  35 /*
  36  * Note: this file was generated by the GROMACS avx_256_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/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_double.h"
  50 #include "kernelutil_x86_avx_256_double.h"
  51
  52 /*
  53  * Gromacs nonbonded kernel:   nb_kernel_ElecGB_VdwNone_GeomP1P1_VF_avx_256_double
  54  * Electrostatics interaction: GeneralizedBorn
  55  * VdW interaction:            None
  56  * Geometry:                   Particle-Particle
  57  * Calculate force/pot:        PotentialAndForce
  58  */
  59 void
  60 nb_kernel_ElecGB_VdwNone_GeomP1P1_VF_avx_256_double
  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 AVX, 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              jnrlistE,jnrlistF,jnrlistG,jnrlistH;
  79     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
  80     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  81     real             rcutoff_scalar;
  82     real             *shiftvec,*fshift,*x,*f;
  83     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
  84     real             scratch[4*DIM];
  85     __m256d          tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
  86     real *           vdwioffsetptr0;
  87     __m256d          ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  88     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
  89     __m256d          jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  90     __m256d          dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
  91     __m256d          velec,felec,velecsum,facel,crf,krf,krf2;
  92     real             *charge;
  93     __m128i          gbitab;
  94     __m256d          vgb,fgb,vgbsum,dvdasum,gbscale,gbtabscale,isaprod,gbqqfactor,gbinvepsdiff,gbeps,dvdatmp;
  95     __m256d          minushalf = _mm256_set1_pd(-0.5);
  96     real             *invsqrta,*dvda,*gbtab;
  97     __m128i          vfitab;
  98     __m128i          ifour       = _mm_set1_epi32(4);
  99     __m256d          rt,vfeps,vftabscale,Y,F,G,H,Heps,Fp,VV,FF;
 100     real             *vftab;
 101     __m256d          dummy_mask,cutoff_mask;
 102     __m128           tmpmask0,tmpmask1;
 103     __m256d          signbit = _mm256_castsi256_pd( _mm256_set1_epi32(0x80000000) );
 104     __m256d          one     = _mm256_set1_pd(1.0);
 105     __m256d          two     = _mm256_set1_pd(2.0);
 106     x                = xx[0];
 107     f                = ff[0];
 108
 109     nri              = nlist->nri;
 110     iinr             = nlist->iinr;
 111     jindex           = nlist->jindex;
 112     jjnr             = nlist->jjnr;
 113     shiftidx         = nlist->shift;
 114     gid              = nlist->gid;
 115     shiftvec         = fr->shift_vec[0];
 116     fshift           = fr->fshift[0];
 117     facel            = _mm256_set1_pd(fr->epsfac);
 118     charge           = mdatoms->chargeA;
 119
 120     invsqrta         = fr->invsqrta;
 121     dvda             = fr->dvda;
 122     gbtabscale       = _mm256_set1_pd(fr->gbtab.scale);
 123     gbtab            = fr->gbtab.data;
 124     gbinvepsdiff     = _mm256_set1_pd((1.0/fr->epsilon_r) - (1.0/fr->gb_epsilon_solvent));
 125
 126     /* Avoid stupid compiler warnings */
 127     jnrA = jnrB = jnrC = jnrD = 0;
 128     j_coord_offsetA = 0;
 129     j_coord_offsetB = 0;
 130     j_coord_offsetC = 0;
 131     j_coord_offsetD = 0;
 132
 133     outeriter        = 0;
 134     inneriter        = 0;
 135
 136     for(iidx=0;iidx<4*DIM;iidx++)
 137     {
 138         scratch[iidx] = 0.0;
 139     }
 140
 141     /* Start outer loop over neighborlists */
 142     for(iidx=0; iidx<nri; iidx++)
 143     {
 144         /* Load shift vector for this list */
 145         i_shift_offset   = DIM*shiftidx[iidx];
 146
 147         /* Load limits for loop over neighbors */
 148         j_index_start    = jindex[iidx];
 149         j_index_end      = jindex[iidx+1];
 150
 151         /* Get outer coordinate index */
 152         inr              = iinr[iidx];
 153         i_coord_offset   = DIM*inr;
 154
 155         /* Load i particle coords and add shift vector */
 156         gmx_mm256_load_shift_and_1rvec_broadcast_pd(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 157
 158         fix0             = _mm256_setzero_pd();
 159         fiy0             = _mm256_setzero_pd();
 160         fiz0             = _mm256_setzero_pd();
 161
 162         /* Load parameters for i particles */
 163         iq0              = _mm256_mul_pd(facel,_mm256_set1_pd(charge[inr+0]));
 164         isai0            = _mm256_set1_pd(invsqrta[inr+0]);
 165
 166         /* Reset potential sums */
 167         velecsum         = _mm256_setzero_pd();
 168         vgbsum           = _mm256_setzero_pd();
 169         dvdasum          = _mm256_setzero_pd();
 170
 171         /* Start inner kernel loop */
 172         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
 173         {
 174
 175             /* Get j neighbor index, and coordinate index */
 176             jnrA             = jjnr[jidx];
 177             jnrB             = jjnr[jidx+1];
 178             jnrC             = jjnr[jidx+2];
 179             jnrD             = jjnr[jidx+3];
 180             j_coord_offsetA  = DIM*jnrA;
 181             j_coord_offsetB  = DIM*jnrB;
 182             j_coord_offsetC  = DIM*jnrC;
 183             j_coord_offsetD  = DIM*jnrD;
 184
 185             /* load j atom coordinates */
 186             gmx_mm256_load_1rvec_4ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
 187                                                  x+j_coord_offsetC,x+j_coord_offsetD,
 188                                                  &jx0,&jy0,&jz0);
 189
 190             /* Calculate displacement vector */
 191             dx00             = _mm256_sub_pd(ix0,jx0);
 192             dy00             = _mm256_sub_pd(iy0,jy0);
 193             dz00             = _mm256_sub_pd(iz0,jz0);
 194
 195             /* Calculate squared distance and things based on it */
 196             rsq00            = gmx_mm256_calc_rsq_pd(dx00,dy00,dz00);
 197
 198             rinv00           = gmx_mm256_invsqrt_pd(rsq00);
 199
 200             /* Load parameters for j particles */
 201             jq0              = gmx_mm256_load_4real_swizzle_pd(charge+jnrA+0,charge+jnrB+0,
 202                                                                  charge+jnrC+0,charge+jnrD+0);
 203             isaj0            = gmx_mm256_load_4real_swizzle_pd(invsqrta+jnrA+0,invsqrta+jnrB+0,
 204                                                                  invsqrta+jnrC+0,invsqrta+jnrD+0);
 205
 206             /**************************
 207              * CALCULATE INTERACTIONS *
 208              **************************/
 209
 210             r00              = _mm256_mul_pd(rsq00,rinv00);
 211
 212             /* Compute parameters for interactions between i and j atoms */
 213             qq00             = _mm256_mul_pd(iq0,jq0);
 214
 215             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
 216             isaprod          = _mm256_mul_pd(isai0,isaj0);
 217             gbqqfactor       = _mm256_xor_pd(signbit,_mm256_mul_pd(qq00,_mm256_mul_pd(isaprod,gbinvepsdiff)));
 218             gbscale          = _mm256_mul_pd(isaprod,gbtabscale);
 219
 220             /* Calculate generalized born table index - this is a separate table from the normal one,
 221              * but we use the same procedure by multiplying r with scale and truncating to integer.
 222              */
 223             rt               = _mm256_mul_pd(r00,gbscale);
 224             gbitab           = _mm256_cvttpd_epi32(rt);
 225             gbeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
 226             gbitab           = _mm_slli_epi32(gbitab,2);
 227             Y                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,0) );
 228             F                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,1) );
 229             G                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,2) );
 230             H                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,3) );
 231             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
 232             Heps             = _mm256_mul_pd(gbeps,H);
 233             Fp               = _mm256_add_pd(F,_mm256_mul_pd(gbeps,_mm256_add_pd(G,Heps)));
 234             VV               = _mm256_add_pd(Y,_mm256_mul_pd(gbeps,Fp));
 235             vgb              = _mm256_mul_pd(gbqqfactor,VV);
 236
 237             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(gbeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
 238             fgb              = _mm256_mul_pd(gbqqfactor,_mm256_mul_pd(FF,gbscale));
 239             dvdatmp          = _mm256_mul_pd(minushalf,_mm256_add_pd(vgb,_mm256_mul_pd(fgb,r00)));
 240             dvdasum          = _mm256_add_pd(dvdasum,dvdatmp);
 241             fjptrA           = dvda+jnrA;
 242             fjptrB           = dvda+jnrB;
 243             fjptrC           = dvda+jnrC;
 244             fjptrD           = dvda+jnrD;
 245             gmx_mm256_increment_4real_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,
 246                                                  _mm256_mul_pd(dvdatmp,_mm256_mul_pd(isaj0,isaj0)));
 247             velec            = _mm256_mul_pd(qq00,rinv00);
 248             felec            = _mm256_mul_pd(_mm256_sub_pd(_mm256_mul_pd(velec,rinv00),fgb),rinv00);
 249
 250             /* Update potential sum for this i atom from the interaction with this j atom. */
 251             velecsum         = _mm256_add_pd(velecsum,velec);
 252             vgbsum           = _mm256_add_pd(vgbsum,vgb);
 253
 254             fscal            = felec;
 255
 256             /* Calculate temporary vectorial force */
 257             tx               = _mm256_mul_pd(fscal,dx00);
 258             ty               = _mm256_mul_pd(fscal,dy00);
 259             tz               = _mm256_mul_pd(fscal,dz00);
 260
 261             /* Update vectorial force */
 262             fix0             = _mm256_add_pd(fix0,tx);
 263             fiy0             = _mm256_add_pd(fiy0,ty);
 264             fiz0             = _mm256_add_pd(fiz0,tz);
 265
 266             fjptrA             = f+j_coord_offsetA;
 267             fjptrB             = f+j_coord_offsetB;
 268             fjptrC             = f+j_coord_offsetC;
 269             fjptrD             = f+j_coord_offsetD;
 270             gmx_mm256_decrement_1rvec_4ptr_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 271
 272             /* Inner loop uses 57 flops */
 273         }
 274
 275         if(jidx<j_index_end)
 276         {
 277
 278             /* Get j neighbor index, and coordinate index */
 279             jnrlistA         = jjnr[jidx];
 280             jnrlistB         = jjnr[jidx+1];
 281             jnrlistC         = jjnr[jidx+2];
 282             jnrlistD         = jjnr[jidx+3];
 283             /* Sign of each element will be negative for non-real atoms.
 284              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
 285              * so use it as val = _mm_andnot_pd(mask,val) to clear dummy entries.
 286              */
 287             tmpmask0 = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
 288
 289             tmpmask1 = _mm_permute_ps(tmpmask0,_GMX_MM_PERMUTE(3,3,2,2));
 290             tmpmask0 = _mm_permute_ps(tmpmask0,_GMX_MM_PERMUTE(1,1,0,0));
 291             dummy_mask = _mm256_castps_pd(gmx_mm256_set_m128(tmpmask1,tmpmask0));
 292
 293             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
 294             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
 295             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
 296             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
 297             j_coord_offsetA  = DIM*jnrA;
 298             j_coord_offsetB  = DIM*jnrB;
 299             j_coord_offsetC  = DIM*jnrC;
 300             j_coord_offsetD  = DIM*jnrD;
 301
 302             /* load j atom coordinates */
 303             gmx_mm256_load_1rvec_4ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
 304                                                  x+j_coord_offsetC,x+j_coord_offsetD,
 305                                                  &jx0,&jy0,&jz0);
 306
 307             /* Calculate displacement vector */
 308             dx00             = _mm256_sub_pd(ix0,jx0);
 309             dy00             = _mm256_sub_pd(iy0,jy0);
 310             dz00             = _mm256_sub_pd(iz0,jz0);
 311
 312             /* Calculate squared distance and things based on it */
 313             rsq00            = gmx_mm256_calc_rsq_pd(dx00,dy00,dz00);
 314
 315             rinv00           = gmx_mm256_invsqrt_pd(rsq00);
 316
 317             /* Load parameters for j particles */
 318             jq0              = gmx_mm256_load_4real_swizzle_pd(charge+jnrA+0,charge+jnrB+0,
 319                                                                  charge+jnrC+0,charge+jnrD+0);
 320             isaj0            = gmx_mm256_load_4real_swizzle_pd(invsqrta+jnrA+0,invsqrta+jnrB+0,
 321                                                                  invsqrta+jnrC+0,invsqrta+jnrD+0);
 322
 323             /**************************
 324              * CALCULATE INTERACTIONS *
 325              **************************/
 326
 327             r00              = _mm256_mul_pd(rsq00,rinv00);
 328             r00              = _mm256_andnot_pd(dummy_mask,r00);
 329
 330             /* Compute parameters for interactions between i and j atoms */
 331             qq00             = _mm256_mul_pd(iq0,jq0);
 332
 333             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
 334             isaprod          = _mm256_mul_pd(isai0,isaj0);
 335             gbqqfactor       = _mm256_xor_pd(signbit,_mm256_mul_pd(qq00,_mm256_mul_pd(isaprod,gbinvepsdiff)));
 336             gbscale          = _mm256_mul_pd(isaprod,gbtabscale);
 337
 338             /* Calculate generalized born table index - this is a separate table from the normal one,
 339              * but we use the same procedure by multiplying r with scale and truncating to integer.
 340              */
 341             rt               = _mm256_mul_pd(r00,gbscale);
 342             gbitab           = _mm256_cvttpd_epi32(rt);
 343             gbeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
 344             gbitab           = _mm_slli_epi32(gbitab,2);
 345             Y                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,0) );
 346             F                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,1) );
 347             G                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,2) );
 348             H                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,3) );
 349             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
 350             Heps             = _mm256_mul_pd(gbeps,H);
 351             Fp               = _mm256_add_pd(F,_mm256_mul_pd(gbeps,_mm256_add_pd(G,Heps)));
 352             VV               = _mm256_add_pd(Y,_mm256_mul_pd(gbeps,Fp));
 353             vgb              = _mm256_mul_pd(gbqqfactor,VV);
 354
 355             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(gbeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
 356             fgb              = _mm256_mul_pd(gbqqfactor,_mm256_mul_pd(FF,gbscale));
 357             dvdatmp          = _mm256_mul_pd(minushalf,_mm256_add_pd(vgb,_mm256_mul_pd(fgb,r00)));
 358             dvdatmp          = _mm256_andnot_pd(dummy_mask,dvdatmp);
 359             dvdasum          = _mm256_add_pd(dvdasum,dvdatmp);
 360             /* The pointers to scratch make sure that this code with compilers that take gmx_restrict seriously (e.g. icc 13) really can't screw things up. */
 361             fjptrA             = (jnrlistA>=0) ? dvda+jnrA : scratch;
 362             fjptrB             = (jnrlistB>=0) ? dvda+jnrB : scratch;
 363             fjptrC             = (jnrlistC>=0) ? dvda+jnrC : scratch;
 364             fjptrD             = (jnrlistD>=0) ? dvda+jnrD : scratch;
 365             gmx_mm256_increment_4real_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,
 366                                                  _mm256_mul_pd(dvdatmp,_mm256_mul_pd(isaj0,isaj0)));
 367             velec            = _mm256_mul_pd(qq00,rinv00);
 368             felec            = _mm256_mul_pd(_mm256_sub_pd(_mm256_mul_pd(velec,rinv00),fgb),rinv00);
 369
 370             /* Update potential sum for this i atom from the interaction with this j atom. */
 371             velec            = _mm256_andnot_pd(dummy_mask,velec);
 372             velecsum         = _mm256_add_pd(velecsum,velec);
 373             vgb              = _mm256_andnot_pd(dummy_mask,vgb);
 374             vgbsum           = _mm256_add_pd(vgbsum,vgb);
 375
 376             fscal            = felec;
 377
 378             fscal            = _mm256_andnot_pd(dummy_mask,fscal);
 379
 380             /* Calculate temporary vectorial force */
 381             tx               = _mm256_mul_pd(fscal,dx00);
 382             ty               = _mm256_mul_pd(fscal,dy00);
 383             tz               = _mm256_mul_pd(fscal,dz00);
 384
 385             /* Update vectorial force */
 386             fix0             = _mm256_add_pd(fix0,tx);
 387             fiy0             = _mm256_add_pd(fiy0,ty);
 388             fiz0             = _mm256_add_pd(fiz0,tz);
 389
 390             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
 391             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
 392             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
 393             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
 394             gmx_mm256_decrement_1rvec_4ptr_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 395
 396             /* Inner loop uses 58 flops */
 397         }
 398
 399         /* End of innermost loop */
 400
 401         gmx_mm256_update_iforce_1atom_swizzle_pd(fix0,fiy0,fiz0,
 402                                                  f+i_coord_offset,fshift+i_shift_offset);
 403
 404         ggid                        = gid[iidx];
 405         /* Update potential energies */
 406         gmx_mm256_update_1pot_pd(velecsum,kernel_data->energygrp_elec+ggid);
 407         gmx_mm256_update_1pot_pd(vgbsum,kernel_data->energygrp_polarization+ggid);
 408         dvdasum = _mm256_mul_pd(dvdasum, _mm256_mul_pd(isai0,isai0));
 409         gmx_mm256_update_1pot_pd(dvdasum,dvda+inr);
 410
 411         /* Increment number of inner iterations */
 412         inneriter                  += j_index_end - j_index_start;
 413
 414         /* Outer loop uses 9 flops */
 415     }
 416
 417     /* Increment number of outer iterations */
 418     outeriter        += nri;
 419
 420     /* Update outer/inner flops */
 421
 422     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VF,outeriter*9 + inneriter*58);
 423 }
 424 /*
 425  * Gromacs nonbonded kernel:   nb_kernel_ElecGB_VdwNone_GeomP1P1_F_avx_256_double
 426  * Electrostatics interaction: GeneralizedBorn
 427  * VdW interaction:            None
 428  * Geometry:                   Particle-Particle
 429  * Calculate force/pot:        Force
 430  */
 431 void
 432 nb_kernel_ElecGB_VdwNone_GeomP1P1_F_avx_256_double
 433                     (t_nblist                    * gmx_restrict       nlist,
 434                      rvec                        * gmx_restrict          xx,
 435                      rvec                        * gmx_restrict          ff,
 436                      t_forcerec                  * gmx_restrict          fr,
 437                      t_mdatoms                   * gmx_restrict     mdatoms,
 438                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 439                      t_nrnb                      * gmx_restrict        nrnb)
 440 {
 441     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
 442      * just 0 for non-waters.
 443      * Suffixes A,B,C,D refer to j loop unrolling done with AVX, e.g. for the four different
 444      * jnr indices corresponding to data put in the four positions in the SIMD register.
 445      */
 446     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
 447     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
 448     int              jnrA,jnrB,jnrC,jnrD;
 449     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
 450     int              jnrlistE,jnrlistF,jnrlistG,jnrlistH;
 451     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
 452     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 453     real             rcutoff_scalar;
 454     real             *shiftvec,*fshift,*x,*f;
 455     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
 456     real             scratch[4*DIM];
 457     __m256d          tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
 458     real *           vdwioffsetptr0;
 459     __m256d          ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 460     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
 461     __m256d          jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 462     __m256d          dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
 463     __m256d          velec,felec,velecsum,facel,crf,krf,krf2;
 464     real             *charge;
 465     __m128i          gbitab;
 466     __m256d          vgb,fgb,vgbsum,dvdasum,gbscale,gbtabscale,isaprod,gbqqfactor,gbinvepsdiff,gbeps,dvdatmp;
 467     __m256d          minushalf = _mm256_set1_pd(-0.5);
 468     real             *invsqrta,*dvda,*gbtab;
 469     __m128i          vfitab;
 470     __m128i          ifour       = _mm_set1_epi32(4);
 471     __m256d          rt,vfeps,vftabscale,Y,F,G,H,Heps,Fp,VV,FF;
 472     real             *vftab;
 473     __m256d          dummy_mask,cutoff_mask;
 474     __m128           tmpmask0,tmpmask1;
 475     __m256d          signbit = _mm256_castsi256_pd( _mm256_set1_epi32(0x80000000) );
 476     __m256d          one     = _mm256_set1_pd(1.0);
 477     __m256d          two     = _mm256_set1_pd(2.0);
 478     x                = xx[0];
 479     f                = ff[0];
 480
 481     nri              = nlist->nri;
 482     iinr             = nlist->iinr;
 483     jindex           = nlist->jindex;
 484     jjnr             = nlist->jjnr;
 485     shiftidx         = nlist->shift;
 486     gid              = nlist->gid;
 487     shiftvec         = fr->shift_vec[0];
 488     fshift           = fr->fshift[0];
 489     facel            = _mm256_set1_pd(fr->epsfac);
 490     charge           = mdatoms->chargeA;
 491
 492     invsqrta         = fr->invsqrta;
 493     dvda             = fr->dvda;
 494     gbtabscale       = _mm256_set1_pd(fr->gbtab.scale);
 495     gbtab            = fr->gbtab.data;
 496     gbinvepsdiff     = _mm256_set1_pd((1.0/fr->epsilon_r) - (1.0/fr->gb_epsilon_solvent));
 497
 498     /* Avoid stupid compiler warnings */
 499     jnrA = jnrB = jnrC = jnrD = 0;
 500     j_coord_offsetA = 0;
 501     j_coord_offsetB = 0;
 502     j_coord_offsetC = 0;
 503     j_coord_offsetD = 0;
 504
 505     outeriter        = 0;
 506     inneriter        = 0;
 507
 508     for(iidx=0;iidx<4*DIM;iidx++)
 509     {
 510         scratch[iidx] = 0.0;
 511     }
 512
 513     /* Start outer loop over neighborlists */
 514     for(iidx=0; iidx<nri; iidx++)
 515     {
 516         /* Load shift vector for this list */
 517         i_shift_offset   = DIM*shiftidx[iidx];
 518
 519         /* Load limits for loop over neighbors */
 520         j_index_start    = jindex[iidx];
 521         j_index_end      = jindex[iidx+1];
 522
 523         /* Get outer coordinate index */
 524         inr              = iinr[iidx];
 525         i_coord_offset   = DIM*inr;
 526
 527         /* Load i particle coords and add shift vector */
 528         gmx_mm256_load_shift_and_1rvec_broadcast_pd(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 529
 530         fix0             = _mm256_setzero_pd();
 531         fiy0             = _mm256_setzero_pd();
 532         fiz0             = _mm256_setzero_pd();
 533
 534         /* Load parameters for i particles */
 535         iq0              = _mm256_mul_pd(facel,_mm256_set1_pd(charge[inr+0]));
 536         isai0            = _mm256_set1_pd(invsqrta[inr+0]);
 537
 538         dvdasum          = _mm256_setzero_pd();
 539
 540         /* Start inner kernel loop */
 541         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
 542         {
 543
 544             /* Get j neighbor index, and coordinate index */
 545             jnrA             = jjnr[jidx];
 546             jnrB             = jjnr[jidx+1];
 547             jnrC             = jjnr[jidx+2];
 548             jnrD             = jjnr[jidx+3];
 549             j_coord_offsetA  = DIM*jnrA;
 550             j_coord_offsetB  = DIM*jnrB;
 551             j_coord_offsetC  = DIM*jnrC;
 552             j_coord_offsetD  = DIM*jnrD;
 553
 554             /* load j atom coordinates */
 555             gmx_mm256_load_1rvec_4ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
 556                                                  x+j_coord_offsetC,x+j_coord_offsetD,
 557                                                  &jx0,&jy0,&jz0);
 558
 559             /* Calculate displacement vector */
 560             dx00             = _mm256_sub_pd(ix0,jx0);
 561             dy00             = _mm256_sub_pd(iy0,jy0);
 562             dz00             = _mm256_sub_pd(iz0,jz0);
 563
 564             /* Calculate squared distance and things based on it */
 565             rsq00            = gmx_mm256_calc_rsq_pd(dx00,dy00,dz00);
 566
 567             rinv00           = gmx_mm256_invsqrt_pd(rsq00);
 568
 569             /* Load parameters for j particles */
 570             jq0              = gmx_mm256_load_4real_swizzle_pd(charge+jnrA+0,charge+jnrB+0,
 571                                                                  charge+jnrC+0,charge+jnrD+0);
 572             isaj0            = gmx_mm256_load_4real_swizzle_pd(invsqrta+jnrA+0,invsqrta+jnrB+0,
 573                                                                  invsqrta+jnrC+0,invsqrta+jnrD+0);
 574
 575             /**************************
 576              * CALCULATE INTERACTIONS *
 577              **************************/
 578
 579             r00              = _mm256_mul_pd(rsq00,rinv00);
 580
 581             /* Compute parameters for interactions between i and j atoms */
 582             qq00             = _mm256_mul_pd(iq0,jq0);
 583
 584             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
 585             isaprod          = _mm256_mul_pd(isai0,isaj0);
 586             gbqqfactor       = _mm256_xor_pd(signbit,_mm256_mul_pd(qq00,_mm256_mul_pd(isaprod,gbinvepsdiff)));
 587             gbscale          = _mm256_mul_pd(isaprod,gbtabscale);
 588
 589             /* Calculate generalized born table index - this is a separate table from the normal one,
 590              * but we use the same procedure by multiplying r with scale and truncating to integer.
 591              */
 592             rt               = _mm256_mul_pd(r00,gbscale);
 593             gbitab           = _mm256_cvttpd_epi32(rt);
 594             gbeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
 595             gbitab           = _mm_slli_epi32(gbitab,2);
 596             Y                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,0) );
 597             F                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,1) );
 598             G                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,2) );
 599             H                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,3) );
 600             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
 601             Heps             = _mm256_mul_pd(gbeps,H);
 602             Fp               = _mm256_add_pd(F,_mm256_mul_pd(gbeps,_mm256_add_pd(G,Heps)));
 603             VV               = _mm256_add_pd(Y,_mm256_mul_pd(gbeps,Fp));
 604             vgb              = _mm256_mul_pd(gbqqfactor,VV);
 605
 606             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(gbeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
 607             fgb              = _mm256_mul_pd(gbqqfactor,_mm256_mul_pd(FF,gbscale));
 608             dvdatmp          = _mm256_mul_pd(minushalf,_mm256_add_pd(vgb,_mm256_mul_pd(fgb,r00)));
 609             dvdasum          = _mm256_add_pd(dvdasum,dvdatmp);
 610             fjptrA           = dvda+jnrA;
 611             fjptrB           = dvda+jnrB;
 612             fjptrC           = dvda+jnrC;
 613             fjptrD           = dvda+jnrD;
 614             gmx_mm256_increment_4real_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,
 615                                                  _mm256_mul_pd(dvdatmp,_mm256_mul_pd(isaj0,isaj0)));
 616             velec            = _mm256_mul_pd(qq00,rinv00);
 617             felec            = _mm256_mul_pd(_mm256_sub_pd(_mm256_mul_pd(velec,rinv00),fgb),rinv00);
 618
 619             fscal            = felec;
 620
 621             /* Calculate temporary vectorial force */
 622             tx               = _mm256_mul_pd(fscal,dx00);
 623             ty               = _mm256_mul_pd(fscal,dy00);
 624             tz               = _mm256_mul_pd(fscal,dz00);
 625
 626             /* Update vectorial force */
 627             fix0             = _mm256_add_pd(fix0,tx);
 628             fiy0             = _mm256_add_pd(fiy0,ty);
 629             fiz0             = _mm256_add_pd(fiz0,tz);
 630
 631             fjptrA             = f+j_coord_offsetA;
 632             fjptrB             = f+j_coord_offsetB;
 633             fjptrC             = f+j_coord_offsetC;
 634             fjptrD             = f+j_coord_offsetD;
 635             gmx_mm256_decrement_1rvec_4ptr_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 636
 637             /* Inner loop uses 55 flops */
 638         }
 639
 640         if(jidx<j_index_end)
 641         {
 642
 643             /* Get j neighbor index, and coordinate index */
 644             jnrlistA         = jjnr[jidx];
 645             jnrlistB         = jjnr[jidx+1];
 646             jnrlistC         = jjnr[jidx+2];
 647             jnrlistD         = jjnr[jidx+3];
 648             /* Sign of each element will be negative for non-real atoms.
 649              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
 650              * so use it as val = _mm_andnot_pd(mask,val) to clear dummy entries.
 651              */
 652             tmpmask0 = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
 653
 654             tmpmask1 = _mm_permute_ps(tmpmask0,_GMX_MM_PERMUTE(3,3,2,2));
 655             tmpmask0 = _mm_permute_ps(tmpmask0,_GMX_MM_PERMUTE(1,1,0,0));
 656             dummy_mask = _mm256_castps_pd(gmx_mm256_set_m128(tmpmask1,tmpmask0));
 657
 658             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
 659             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
 660             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
 661             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
 662             j_coord_offsetA  = DIM*jnrA;
 663             j_coord_offsetB  = DIM*jnrB;
 664             j_coord_offsetC  = DIM*jnrC;
 665             j_coord_offsetD  = DIM*jnrD;
 666
 667             /* load j atom coordinates */
 668             gmx_mm256_load_1rvec_4ptr_swizzle_pd(x+j_coord_offsetA,x+j_coord_offsetB,
 669                                                  x+j_coord_offsetC,x+j_coord_offsetD,
 670                                                  &jx0,&jy0,&jz0);
 671
 672             /* Calculate displacement vector */
 673             dx00             = _mm256_sub_pd(ix0,jx0);
 674             dy00             = _mm256_sub_pd(iy0,jy0);
 675             dz00             = _mm256_sub_pd(iz0,jz0);
 676
 677             /* Calculate squared distance and things based on it */
 678             rsq00            = gmx_mm256_calc_rsq_pd(dx00,dy00,dz00);
 679
 680             rinv00           = gmx_mm256_invsqrt_pd(rsq00);
 681
 682             /* Load parameters for j particles */
 683             jq0              = gmx_mm256_load_4real_swizzle_pd(charge+jnrA+0,charge+jnrB+0,
 684                                                                  charge+jnrC+0,charge+jnrD+0);
 685             isaj0            = gmx_mm256_load_4real_swizzle_pd(invsqrta+jnrA+0,invsqrta+jnrB+0,
 686                                                                  invsqrta+jnrC+0,invsqrta+jnrD+0);
 687
 688             /**************************
 689              * CALCULATE INTERACTIONS *
 690              **************************/
 691
 692             r00              = _mm256_mul_pd(rsq00,rinv00);
 693             r00              = _mm256_andnot_pd(dummy_mask,r00);
 694
 695             /* Compute parameters for interactions between i and j atoms */
 696             qq00             = _mm256_mul_pd(iq0,jq0);
 697
 698             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
 699             isaprod          = _mm256_mul_pd(isai0,isaj0);
 700             gbqqfactor       = _mm256_xor_pd(signbit,_mm256_mul_pd(qq00,_mm256_mul_pd(isaprod,gbinvepsdiff)));
 701             gbscale          = _mm256_mul_pd(isaprod,gbtabscale);
 702
 703             /* Calculate generalized born table index - this is a separate table from the normal one,
 704              * but we use the same procedure by multiplying r with scale and truncating to integer.
 705              */
 706             rt               = _mm256_mul_pd(r00,gbscale);
 707             gbitab           = _mm256_cvttpd_epi32(rt);
 708             gbeps            = _mm256_sub_pd(rt,_mm256_round_pd(rt, _MM_FROUND_FLOOR));
 709             gbitab           = _mm_slli_epi32(gbitab,2);
 710             Y                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,0) );
 711             F                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,1) );
 712             G                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,2) );
 713             H                = _mm256_load_pd( gbtab + _mm_extract_epi32(gbitab,3) );
 714             GMX_MM256_FULLTRANSPOSE4_PD(Y,F,G,H);
 715             Heps             = _mm256_mul_pd(gbeps,H);
 716             Fp               = _mm256_add_pd(F,_mm256_mul_pd(gbeps,_mm256_add_pd(G,Heps)));
 717             VV               = _mm256_add_pd(Y,_mm256_mul_pd(gbeps,Fp));
 718             vgb              = _mm256_mul_pd(gbqqfactor,VV);
 719
 720             FF               = _mm256_add_pd(Fp,_mm256_mul_pd(gbeps,_mm256_add_pd(G,_mm256_add_pd(Heps,Heps))));
 721             fgb              = _mm256_mul_pd(gbqqfactor,_mm256_mul_pd(FF,gbscale));
 722             dvdatmp          = _mm256_mul_pd(minushalf,_mm256_add_pd(vgb,_mm256_mul_pd(fgb,r00)));
 723             dvdatmp          = _mm256_andnot_pd(dummy_mask,dvdatmp);
 724             dvdasum          = _mm256_add_pd(dvdasum,dvdatmp);
 725             /* The pointers to scratch make sure that this code with compilers that take gmx_restrict seriously (e.g. icc 13) really can't screw things up. */
 726             fjptrA             = (jnrlistA>=0) ? dvda+jnrA : scratch;
 727             fjptrB             = (jnrlistB>=0) ? dvda+jnrB : scratch;
 728             fjptrC             = (jnrlistC>=0) ? dvda+jnrC : scratch;
 729             fjptrD             = (jnrlistD>=0) ? dvda+jnrD : scratch;
 730             gmx_mm256_increment_4real_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,
 731                                                  _mm256_mul_pd(dvdatmp,_mm256_mul_pd(isaj0,isaj0)));
 732             velec            = _mm256_mul_pd(qq00,rinv00);
 733             felec            = _mm256_mul_pd(_mm256_sub_pd(_mm256_mul_pd(velec,rinv00),fgb),rinv00);
 734
 735             fscal            = felec;
 736
 737             fscal            = _mm256_andnot_pd(dummy_mask,fscal);
 738
 739             /* Calculate temporary vectorial force */
 740             tx               = _mm256_mul_pd(fscal,dx00);
 741             ty               = _mm256_mul_pd(fscal,dy00);
 742             tz               = _mm256_mul_pd(fscal,dz00);
 743
 744             /* Update vectorial force */
 745             fix0             = _mm256_add_pd(fix0,tx);
 746             fiy0             = _mm256_add_pd(fiy0,ty);
 747             fiz0             = _mm256_add_pd(fiz0,tz);
 748
 749             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
 750             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
 751             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
 752             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
 753             gmx_mm256_decrement_1rvec_4ptr_swizzle_pd(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 754
 755             /* Inner loop uses 56 flops */
 756         }
 757
 758         /* End of innermost loop */
 759
 760         gmx_mm256_update_iforce_1atom_swizzle_pd(fix0,fiy0,fiz0,
 761                                                  f+i_coord_offset,fshift+i_shift_offset);
 762
 763         dvdasum = _mm256_mul_pd(dvdasum, _mm256_mul_pd(isai0,isai0));
 764         gmx_mm256_update_1pot_pd(dvdasum,dvda+inr);
 765
 766         /* Increment number of inner iterations */
 767         inneriter                  += j_index_end - j_index_start;
 768
 769         /* Outer loop uses 7 flops */
 770     }
 771
 772     /* Increment number of outer iterations */
 773     outeriter        += nri;
 774
 775     /* Update outer/inner flops */
 776
 777     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_F,outeriter*7 + inneriter*56);
 778 }