src/gromacs/gmxlib/nonbonded/nb_kernel_sse2_single/nb_kernel_ElecGB_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
  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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  17  * Lesser General Public License for more details.
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  34  */
  35 /*
  36  * Note: this file was generated by the GROMACS sse2_single kernel generator.
  37  */
  38 #include "config.h"
  39
  40 #include <math.h>
  41
  42 #include "../nb_kernel.h"
  43 #include "gromacs/legacyheaders/types/simple.h"
  44 #include "gromacs/math/vec.h"
  45 #include "gromacs/legacyheaders/nrnb.h"
  46
  47 #include "gromacs/simd/math_x86_sse2_single.h"
  48 #include "kernelutil_x86_sse2_single.h"
  49
  50 /*
  51  * Gromacs nonbonded kernel:   nb_kernel_ElecGB_VdwNone_GeomP1P1_VF_sse2_single
  52  * Electrostatics interaction: GeneralizedBorn
  53  * VdW interaction:            None
  54  * Geometry:                   Particle-Particle
  55  * Calculate force/pot:        PotentialAndForce
  56  */
  57 void
  58 nb_kernel_ElecGB_VdwNone_GeomP1P1_VF_sse2_single
  59                     (t_nblist                    * gmx_restrict       nlist,
  60                      rvec                        * gmx_restrict          xx,
  61                      rvec                        * gmx_restrict          ff,
  62                      t_forcerec                  * gmx_restrict          fr,
  63                      t_mdatoms                   * gmx_restrict     mdatoms,
  64                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
  65                      t_nrnb                      * gmx_restrict        nrnb)
  66 {
  67     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
  68      * just 0 for non-waters.
  69      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
  70      * jnr indices corresponding to data put in the four positions in the SIMD register.
  71      */
  72     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
  73     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
  74     int              jnrA,jnrB,jnrC,jnrD;
  75     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
  76     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
  77     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  78     real             rcutoff_scalar;
  79     real             *shiftvec,*fshift,*x,*f;
  80     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
  81     real             scratch[4*DIM];
  82     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
  83     int              vdwioffset0;
  84     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  85     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
  86     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  87     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
  88     __m128           velec,felec,velecsum,facel,crf,krf,krf2;
  89     real             *charge;
  90     __m128i          gbitab;
  91     __m128           vgb,fgb,vgbsum,dvdasum,gbscale,gbtabscale,isaprod,gbqqfactor,gbinvepsdiff,gbeps,dvdatmp;
  92     __m128           minushalf = _mm_set1_ps(-0.5);
  93     real             *invsqrta,*dvda,*gbtab;
  94     __m128i          vfitab;
  95     __m128i          ifour       = _mm_set1_epi32(4);
  96     __m128           rt,vfeps,vftabscale,Y,F,G,H,Heps,Fp,VV,FF;
  97     real             *vftab;
  98     __m128           dummy_mask,cutoff_mask;
  99     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
 100     __m128           one     = _mm_set1_ps(1.0);
 101     __m128           two     = _mm_set1_ps(2.0);
 102     x                = xx[0];
 103     f                = ff[0];
 104
 105     nri              = nlist->nri;
 106     iinr             = nlist->iinr;
 107     jindex           = nlist->jindex;
 108     jjnr             = nlist->jjnr;
 109     shiftidx         = nlist->shift;
 110     gid              = nlist->gid;
 111     shiftvec         = fr->shift_vec[0];
 112     fshift           = fr->fshift[0];
 113     facel            = _mm_set1_ps(fr->epsfac);
 114     charge           = mdatoms->chargeA;
 115
 116     invsqrta         = fr->invsqrta;
 117     dvda             = fr->dvda;
 118     gbtabscale       = _mm_set1_ps(fr->gbtab.scale);
 119     gbtab            = fr->gbtab.data;
 120     gbinvepsdiff     = _mm_set1_ps((1.0/fr->epsilon_r) - (1.0/fr->gb_epsilon_solvent));
 121
 122     /* Avoid stupid compiler warnings */
 123     jnrA = jnrB = jnrC = jnrD = 0;
 124     j_coord_offsetA = 0;
 125     j_coord_offsetB = 0;
 126     j_coord_offsetC = 0;
 127     j_coord_offsetD = 0;
 128
 129     outeriter        = 0;
 130     inneriter        = 0;
 131
 132     for(iidx=0;iidx<4*DIM;iidx++)
 133     {
 134         scratch[iidx] = 0.0;
 135     }
 136
 137     /* Start outer loop over neighborlists */
 138     for(iidx=0; iidx<nri; iidx++)
 139     {
 140         /* Load shift vector for this list */
 141         i_shift_offset   = DIM*shiftidx[iidx];
 142
 143         /* Load limits for loop over neighbors */
 144         j_index_start    = jindex[iidx];
 145         j_index_end      = jindex[iidx+1];
 146
 147         /* Get outer coordinate index */
 148         inr              = iinr[iidx];
 149         i_coord_offset   = DIM*inr;
 150
 151         /* Load i particle coords and add shift vector */
 152         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 153
 154         fix0             = _mm_setzero_ps();
 155         fiy0             = _mm_setzero_ps();
 156         fiz0             = _mm_setzero_ps();
 157
 158         /* Load parameters for i particles */
 159         iq0              = _mm_mul_ps(facel,_mm_load1_ps(charge+inr+0));
 160         isai0            = _mm_load1_ps(invsqrta+inr+0);
 161
 162         /* Reset potential sums */
 163         velecsum         = _mm_setzero_ps();
 164         vgbsum           = _mm_setzero_ps();
 165         dvdasum          = _mm_setzero_ps();
 166
 167         /* Start inner kernel loop */
 168         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
 169         {
 170
 171             /* Get j neighbor index, and coordinate index */
 172             jnrA             = jjnr[jidx];
 173             jnrB             = jjnr[jidx+1];
 174             jnrC             = jjnr[jidx+2];
 175             jnrD             = jjnr[jidx+3];
 176             j_coord_offsetA  = DIM*jnrA;
 177             j_coord_offsetB  = DIM*jnrB;
 178             j_coord_offsetC  = DIM*jnrC;
 179             j_coord_offsetD  = DIM*jnrD;
 180
 181             /* load j atom coordinates */
 182             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 183                                               x+j_coord_offsetC,x+j_coord_offsetD,
 184                                               &jx0,&jy0,&jz0);
 185
 186             /* Calculate displacement vector */
 187             dx00             = _mm_sub_ps(ix0,jx0);
 188             dy00             = _mm_sub_ps(iy0,jy0);
 189             dz00             = _mm_sub_ps(iz0,jz0);
 190
 191             /* Calculate squared distance and things based on it */
 192             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 193
 194             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 195
 196             /* Load parameters for j particles */
 197             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 198                                                               charge+jnrC+0,charge+jnrD+0);
 199             isaj0            = gmx_mm_load_4real_swizzle_ps(invsqrta+jnrA+0,invsqrta+jnrB+0,
 200                                                               invsqrta+jnrC+0,invsqrta+jnrD+0);
 201
 202             /**************************
 203              * CALCULATE INTERACTIONS *
 204              **************************/
 205
 206             r00              = _mm_mul_ps(rsq00,rinv00);
 207
 208             /* Compute parameters for interactions between i and j atoms */
 209             qq00             = _mm_mul_ps(iq0,jq0);
 210
 211             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
 212             isaprod          = _mm_mul_ps(isai0,isaj0);
 213             gbqqfactor       = _mm_xor_ps(signbit,_mm_mul_ps(qq00,_mm_mul_ps(isaprod,gbinvepsdiff)));
 214             gbscale          = _mm_mul_ps(isaprod,gbtabscale);
 215
 216             /* Calculate generalized born table index - this is a separate table from the normal one,
 217              * but we use the same procedure by multiplying r with scale and truncating to integer.
 218              */
 219             rt               = _mm_mul_ps(r00,gbscale);
 220             gbitab           = _mm_cvttps_epi32(rt);
 221             gbeps            = _mm_sub_ps(rt,_mm_cvtepi32_ps(gbitab));
 222             gbitab           = _mm_slli_epi32(gbitab,2);
 223
 224             Y                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,0) );
 225             F                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,1) );
 226             G                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,2) );
 227             H                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,3) );
 228             _MM_TRANSPOSE4_PS(Y,F,G,H);
 229             Heps             = _mm_mul_ps(gbeps,H);
 230             Fp               = _mm_add_ps(F,_mm_mul_ps(gbeps,_mm_add_ps(G,Heps)));
 231             VV               = _mm_add_ps(Y,_mm_mul_ps(gbeps,Fp));
 232             vgb              = _mm_mul_ps(gbqqfactor,VV);
 233
 234             FF               = _mm_add_ps(Fp,_mm_mul_ps(gbeps,_mm_add_ps(G,_mm_add_ps(Heps,Heps))));
 235             fgb              = _mm_mul_ps(gbqqfactor,_mm_mul_ps(FF,gbscale));
 236             dvdatmp          = _mm_mul_ps(minushalf,_mm_add_ps(vgb,_mm_mul_ps(fgb,r00)));
 237             dvdasum          = _mm_add_ps(dvdasum,dvdatmp);
 238             fjptrA           = dvda+jnrA;
 239             fjptrB           = dvda+jnrB;
 240             fjptrC           = dvda+jnrC;
 241             fjptrD           = dvda+jnrD;
 242             gmx_mm_increment_4real_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,_mm_mul_ps(dvdatmp,_mm_mul_ps(isaj0,isaj0)));
 243             velec            = _mm_mul_ps(qq00,rinv00);
 244             felec            = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(velec,rinv00),fgb),rinv00);
 245
 246             /* Update potential sum for this i atom from the interaction with this j atom. */
 247             velecsum         = _mm_add_ps(velecsum,velec);
 248             vgbsum           = _mm_add_ps(vgbsum,vgb);
 249
 250             fscal            = felec;
 251
 252             /* Calculate temporary vectorial force */
 253             tx               = _mm_mul_ps(fscal,dx00);
 254             ty               = _mm_mul_ps(fscal,dy00);
 255             tz               = _mm_mul_ps(fscal,dz00);
 256
 257             /* Update vectorial force */
 258             fix0             = _mm_add_ps(fix0,tx);
 259             fiy0             = _mm_add_ps(fiy0,ty);
 260             fiz0             = _mm_add_ps(fiz0,tz);
 261
 262             fjptrA             = f+j_coord_offsetA;
 263             fjptrB             = f+j_coord_offsetB;
 264             fjptrC             = f+j_coord_offsetC;
 265             fjptrD             = f+j_coord_offsetD;
 266             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 267
 268             /* Inner loop uses 58 flops */
 269         }
 270
 271         if(jidx<j_index_end)
 272         {
 273
 274             /* Get j neighbor index, and coordinate index */
 275             jnrlistA         = jjnr[jidx];
 276             jnrlistB         = jjnr[jidx+1];
 277             jnrlistC         = jjnr[jidx+2];
 278             jnrlistD         = jjnr[jidx+3];
 279             /* Sign of each element will be negative for non-real atoms.
 280              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
 281              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
 282              */
 283             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
 284             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
 285             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
 286             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
 287             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
 288             j_coord_offsetA  = DIM*jnrA;
 289             j_coord_offsetB  = DIM*jnrB;
 290             j_coord_offsetC  = DIM*jnrC;
 291             j_coord_offsetD  = DIM*jnrD;
 292
 293             /* load j atom coordinates */
 294             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 295                                               x+j_coord_offsetC,x+j_coord_offsetD,
 296                                               &jx0,&jy0,&jz0);
 297
 298             /* Calculate displacement vector */
 299             dx00             = _mm_sub_ps(ix0,jx0);
 300             dy00             = _mm_sub_ps(iy0,jy0);
 301             dz00             = _mm_sub_ps(iz0,jz0);
 302
 303             /* Calculate squared distance and things based on it */
 304             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 305
 306             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 307
 308             /* Load parameters for j particles */
 309             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 310                                                               charge+jnrC+0,charge+jnrD+0);
 311             isaj0            = gmx_mm_load_4real_swizzle_ps(invsqrta+jnrA+0,invsqrta+jnrB+0,
 312                                                               invsqrta+jnrC+0,invsqrta+jnrD+0);
 313
 314             /**************************
 315              * CALCULATE INTERACTIONS *
 316              **************************/
 317
 318             r00              = _mm_mul_ps(rsq00,rinv00);
 319             r00              = _mm_andnot_ps(dummy_mask,r00);
 320
 321             /* Compute parameters for interactions between i and j atoms */
 322             qq00             = _mm_mul_ps(iq0,jq0);
 323
 324             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
 325             isaprod          = _mm_mul_ps(isai0,isaj0);
 326             gbqqfactor       = _mm_xor_ps(signbit,_mm_mul_ps(qq00,_mm_mul_ps(isaprod,gbinvepsdiff)));
 327             gbscale          = _mm_mul_ps(isaprod,gbtabscale);
 328
 329             /* Calculate generalized born table index - this is a separate table from the normal one,
 330              * but we use the same procedure by multiplying r with scale and truncating to integer.
 331              */
 332             rt               = _mm_mul_ps(r00,gbscale);
 333             gbitab           = _mm_cvttps_epi32(rt);
 334             gbeps            = _mm_sub_ps(rt,_mm_cvtepi32_ps(gbitab));
 335             gbitab           = _mm_slli_epi32(gbitab,2);
 336
 337             Y                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,0) );
 338             F                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,1) );
 339             G                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,2) );
 340             H                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,3) );
 341             _MM_TRANSPOSE4_PS(Y,F,G,H);
 342             Heps             = _mm_mul_ps(gbeps,H);
 343             Fp               = _mm_add_ps(F,_mm_mul_ps(gbeps,_mm_add_ps(G,Heps)));
 344             VV               = _mm_add_ps(Y,_mm_mul_ps(gbeps,Fp));
 345             vgb              = _mm_mul_ps(gbqqfactor,VV);
 346
 347             FF               = _mm_add_ps(Fp,_mm_mul_ps(gbeps,_mm_add_ps(G,_mm_add_ps(Heps,Heps))));
 348             fgb              = _mm_mul_ps(gbqqfactor,_mm_mul_ps(FF,gbscale));
 349             dvdatmp          = _mm_mul_ps(minushalf,_mm_add_ps(vgb,_mm_mul_ps(fgb,r00)));
 350             dvdatmp          = _mm_andnot_ps(dummy_mask,dvdatmp);
 351             dvdasum          = _mm_add_ps(dvdasum,dvdatmp);
 352             /* 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. */
 353             fjptrA             = (jnrlistA>=0) ? dvda+jnrA : scratch;
 354             fjptrB             = (jnrlistB>=0) ? dvda+jnrB : scratch;
 355             fjptrC             = (jnrlistC>=0) ? dvda+jnrC : scratch;
 356             fjptrD             = (jnrlistD>=0) ? dvda+jnrD : scratch;
 357             gmx_mm_increment_4real_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,_mm_mul_ps(dvdatmp,_mm_mul_ps(isaj0,isaj0)));
 358             velec            = _mm_mul_ps(qq00,rinv00);
 359             felec            = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(velec,rinv00),fgb),rinv00);
 360
 361             /* Update potential sum for this i atom from the interaction with this j atom. */
 362             velec            = _mm_andnot_ps(dummy_mask,velec);
 363             velecsum         = _mm_add_ps(velecsum,velec);
 364             vgb              = _mm_andnot_ps(dummy_mask,vgb);
 365             vgbsum           = _mm_add_ps(vgbsum,vgb);
 366
 367             fscal            = felec;
 368
 369             fscal            = _mm_andnot_ps(dummy_mask,fscal);
 370
 371             /* Calculate temporary vectorial force */
 372             tx               = _mm_mul_ps(fscal,dx00);
 373             ty               = _mm_mul_ps(fscal,dy00);
 374             tz               = _mm_mul_ps(fscal,dz00);
 375
 376             /* Update vectorial force */
 377             fix0             = _mm_add_ps(fix0,tx);
 378             fiy0             = _mm_add_ps(fiy0,ty);
 379             fiz0             = _mm_add_ps(fiz0,tz);
 380
 381             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
 382             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
 383             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
 384             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
 385             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 386
 387             /* Inner loop uses 59 flops */
 388         }
 389
 390         /* End of innermost loop */
 391
 392         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
 393                                               f+i_coord_offset,fshift+i_shift_offset);
 394
 395         ggid                        = gid[iidx];
 396         /* Update potential energies */
 397         gmx_mm_update_1pot_ps(velecsum,kernel_data->energygrp_elec+ggid);
 398         gmx_mm_update_1pot_ps(vgbsum,kernel_data->energygrp_polarization+ggid);
 399         dvdasum = _mm_mul_ps(dvdasum, _mm_mul_ps(isai0,isai0));
 400         gmx_mm_update_1pot_ps(dvdasum,dvda+inr);
 401
 402         /* Increment number of inner iterations */
 403         inneriter                  += j_index_end - j_index_start;
 404
 405         /* Outer loop uses 9 flops */
 406     }
 407
 408     /* Increment number of outer iterations */
 409     outeriter        += nri;
 410
 411     /* Update outer/inner flops */
 412
 413     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VF,outeriter*9 + inneriter*59);
 414 }
 415 /*
 416  * Gromacs nonbonded kernel:   nb_kernel_ElecGB_VdwNone_GeomP1P1_F_sse2_single
 417  * Electrostatics interaction: GeneralizedBorn
 418  * VdW interaction:            None
 419  * Geometry:                   Particle-Particle
 420  * Calculate force/pot:        Force
 421  */
 422 void
 423 nb_kernel_ElecGB_VdwNone_GeomP1P1_F_sse2_single
 424                     (t_nblist                    * gmx_restrict       nlist,
 425                      rvec                        * gmx_restrict          xx,
 426                      rvec                        * gmx_restrict          ff,
 427                      t_forcerec                  * gmx_restrict          fr,
 428                      t_mdatoms                   * gmx_restrict     mdatoms,
 429                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 430                      t_nrnb                      * gmx_restrict        nrnb)
 431 {
 432     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
 433      * just 0 for non-waters.
 434      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
 435      * jnr indices corresponding to data put in the four positions in the SIMD register.
 436      */
 437     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
 438     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
 439     int              jnrA,jnrB,jnrC,jnrD;
 440     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
 441     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
 442     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 443     real             rcutoff_scalar;
 444     real             *shiftvec,*fshift,*x,*f;
 445     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
 446     real             scratch[4*DIM];
 447     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
 448     int              vdwioffset0;
 449     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 450     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
 451     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 452     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
 453     __m128           velec,felec,velecsum,facel,crf,krf,krf2;
 454     real             *charge;
 455     __m128i          gbitab;
 456     __m128           vgb,fgb,vgbsum,dvdasum,gbscale,gbtabscale,isaprod,gbqqfactor,gbinvepsdiff,gbeps,dvdatmp;
 457     __m128           minushalf = _mm_set1_ps(-0.5);
 458     real             *invsqrta,*dvda,*gbtab;
 459     __m128i          vfitab;
 460     __m128i          ifour       = _mm_set1_epi32(4);
 461     __m128           rt,vfeps,vftabscale,Y,F,G,H,Heps,Fp,VV,FF;
 462     real             *vftab;
 463     __m128           dummy_mask,cutoff_mask;
 464     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
 465     __m128           one     = _mm_set1_ps(1.0);
 466     __m128           two     = _mm_set1_ps(2.0);
 467     x                = xx[0];
 468     f                = ff[0];
 469
 470     nri              = nlist->nri;
 471     iinr             = nlist->iinr;
 472     jindex           = nlist->jindex;
 473     jjnr             = nlist->jjnr;
 474     shiftidx         = nlist->shift;
 475     gid              = nlist->gid;
 476     shiftvec         = fr->shift_vec[0];
 477     fshift           = fr->fshift[0];
 478     facel            = _mm_set1_ps(fr->epsfac);
 479     charge           = mdatoms->chargeA;
 480
 481     invsqrta         = fr->invsqrta;
 482     dvda             = fr->dvda;
 483     gbtabscale       = _mm_set1_ps(fr->gbtab.scale);
 484     gbtab            = fr->gbtab.data;
 485     gbinvepsdiff     = _mm_set1_ps((1.0/fr->epsilon_r) - (1.0/fr->gb_epsilon_solvent));
 486
 487     /* Avoid stupid compiler warnings */
 488     jnrA = jnrB = jnrC = jnrD = 0;
 489     j_coord_offsetA = 0;
 490     j_coord_offsetB = 0;
 491     j_coord_offsetC = 0;
 492     j_coord_offsetD = 0;
 493
 494     outeriter        = 0;
 495     inneriter        = 0;
 496
 497     for(iidx=0;iidx<4*DIM;iidx++)
 498     {
 499         scratch[iidx] = 0.0;
 500     }
 501
 502     /* Start outer loop over neighborlists */
 503     for(iidx=0; iidx<nri; iidx++)
 504     {
 505         /* Load shift vector for this list */
 506         i_shift_offset   = DIM*shiftidx[iidx];
 507
 508         /* Load limits for loop over neighbors */
 509         j_index_start    = jindex[iidx];
 510         j_index_end      = jindex[iidx+1];
 511
 512         /* Get outer coordinate index */
 513         inr              = iinr[iidx];
 514         i_coord_offset   = DIM*inr;
 515
 516         /* Load i particle coords and add shift vector */
 517         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 518
 519         fix0             = _mm_setzero_ps();
 520         fiy0             = _mm_setzero_ps();
 521         fiz0             = _mm_setzero_ps();
 522
 523         /* Load parameters for i particles */
 524         iq0              = _mm_mul_ps(facel,_mm_load1_ps(charge+inr+0));
 525         isai0            = _mm_load1_ps(invsqrta+inr+0);
 526
 527         dvdasum          = _mm_setzero_ps();
 528
 529         /* Start inner kernel loop */
 530         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
 531         {
 532
 533             /* Get j neighbor index, and coordinate index */
 534             jnrA             = jjnr[jidx];
 535             jnrB             = jjnr[jidx+1];
 536             jnrC             = jjnr[jidx+2];
 537             jnrD             = jjnr[jidx+3];
 538             j_coord_offsetA  = DIM*jnrA;
 539             j_coord_offsetB  = DIM*jnrB;
 540             j_coord_offsetC  = DIM*jnrC;
 541             j_coord_offsetD  = DIM*jnrD;
 542
 543             /* load j atom coordinates */
 544             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 545                                               x+j_coord_offsetC,x+j_coord_offsetD,
 546                                               &jx0,&jy0,&jz0);
 547
 548             /* Calculate displacement vector */
 549             dx00             = _mm_sub_ps(ix0,jx0);
 550             dy00             = _mm_sub_ps(iy0,jy0);
 551             dz00             = _mm_sub_ps(iz0,jz0);
 552
 553             /* Calculate squared distance and things based on it */
 554             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 555
 556             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 557
 558             /* Load parameters for j particles */
 559             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 560                                                               charge+jnrC+0,charge+jnrD+0);
 561             isaj0            = gmx_mm_load_4real_swizzle_ps(invsqrta+jnrA+0,invsqrta+jnrB+0,
 562                                                               invsqrta+jnrC+0,invsqrta+jnrD+0);
 563
 564             /**************************
 565              * CALCULATE INTERACTIONS *
 566              **************************/
 567
 568             r00              = _mm_mul_ps(rsq00,rinv00);
 569
 570             /* Compute parameters for interactions between i and j atoms */
 571             qq00             = _mm_mul_ps(iq0,jq0);
 572
 573             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
 574             isaprod          = _mm_mul_ps(isai0,isaj0);
 575             gbqqfactor       = _mm_xor_ps(signbit,_mm_mul_ps(qq00,_mm_mul_ps(isaprod,gbinvepsdiff)));
 576             gbscale          = _mm_mul_ps(isaprod,gbtabscale);
 577
 578             /* Calculate generalized born table index - this is a separate table from the normal one,
 579              * but we use the same procedure by multiplying r with scale and truncating to integer.
 580              */
 581             rt               = _mm_mul_ps(r00,gbscale);
 582             gbitab           = _mm_cvttps_epi32(rt);
 583             gbeps            = _mm_sub_ps(rt,_mm_cvtepi32_ps(gbitab));
 584             gbitab           = _mm_slli_epi32(gbitab,2);
 585
 586             Y                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,0) );
 587             F                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,1) );
 588             G                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,2) );
 589             H                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,3) );
 590             _MM_TRANSPOSE4_PS(Y,F,G,H);
 591             Heps             = _mm_mul_ps(gbeps,H);
 592             Fp               = _mm_add_ps(F,_mm_mul_ps(gbeps,_mm_add_ps(G,Heps)));
 593             VV               = _mm_add_ps(Y,_mm_mul_ps(gbeps,Fp));
 594             vgb              = _mm_mul_ps(gbqqfactor,VV);
 595
 596             FF               = _mm_add_ps(Fp,_mm_mul_ps(gbeps,_mm_add_ps(G,_mm_add_ps(Heps,Heps))));
 597             fgb              = _mm_mul_ps(gbqqfactor,_mm_mul_ps(FF,gbscale));
 598             dvdatmp          = _mm_mul_ps(minushalf,_mm_add_ps(vgb,_mm_mul_ps(fgb,r00)));
 599             dvdasum          = _mm_add_ps(dvdasum,dvdatmp);
 600             fjptrA           = dvda+jnrA;
 601             fjptrB           = dvda+jnrB;
 602             fjptrC           = dvda+jnrC;
 603             fjptrD           = dvda+jnrD;
 604             gmx_mm_increment_4real_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,_mm_mul_ps(dvdatmp,_mm_mul_ps(isaj0,isaj0)));
 605             velec            = _mm_mul_ps(qq00,rinv00);
 606             felec            = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(velec,rinv00),fgb),rinv00);
 607
 608             fscal            = felec;
 609
 610             /* Calculate temporary vectorial force */
 611             tx               = _mm_mul_ps(fscal,dx00);
 612             ty               = _mm_mul_ps(fscal,dy00);
 613             tz               = _mm_mul_ps(fscal,dz00);
 614
 615             /* Update vectorial force */
 616             fix0             = _mm_add_ps(fix0,tx);
 617             fiy0             = _mm_add_ps(fiy0,ty);
 618             fiz0             = _mm_add_ps(fiz0,tz);
 619
 620             fjptrA             = f+j_coord_offsetA;
 621             fjptrB             = f+j_coord_offsetB;
 622             fjptrC             = f+j_coord_offsetC;
 623             fjptrD             = f+j_coord_offsetD;
 624             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 625
 626             /* Inner loop uses 56 flops */
 627         }
 628
 629         if(jidx<j_index_end)
 630         {
 631
 632             /* Get j neighbor index, and coordinate index */
 633             jnrlistA         = jjnr[jidx];
 634             jnrlistB         = jjnr[jidx+1];
 635             jnrlistC         = jjnr[jidx+2];
 636             jnrlistD         = jjnr[jidx+3];
 637             /* Sign of each element will be negative for non-real atoms.
 638              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
 639              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
 640              */
 641             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
 642             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
 643             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
 644             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
 645             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
 646             j_coord_offsetA  = DIM*jnrA;
 647             j_coord_offsetB  = DIM*jnrB;
 648             j_coord_offsetC  = DIM*jnrC;
 649             j_coord_offsetD  = DIM*jnrD;
 650
 651             /* load j atom coordinates */
 652             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 653                                               x+j_coord_offsetC,x+j_coord_offsetD,
 654                                               &jx0,&jy0,&jz0);
 655
 656             /* Calculate displacement vector */
 657             dx00             = _mm_sub_ps(ix0,jx0);
 658             dy00             = _mm_sub_ps(iy0,jy0);
 659             dz00             = _mm_sub_ps(iz0,jz0);
 660
 661             /* Calculate squared distance and things based on it */
 662             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 663
 664             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 665
 666             /* Load parameters for j particles */
 667             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 668                                                               charge+jnrC+0,charge+jnrD+0);
 669             isaj0            = gmx_mm_load_4real_swizzle_ps(invsqrta+jnrA+0,invsqrta+jnrB+0,
 670                                                               invsqrta+jnrC+0,invsqrta+jnrD+0);
 671
 672             /**************************
 673              * CALCULATE INTERACTIONS *
 674              **************************/
 675
 676             r00              = _mm_mul_ps(rsq00,rinv00);
 677             r00              = _mm_andnot_ps(dummy_mask,r00);
 678
 679             /* Compute parameters for interactions between i and j atoms */
 680             qq00             = _mm_mul_ps(iq0,jq0);
 681
 682             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
 683             isaprod          = _mm_mul_ps(isai0,isaj0);
 684             gbqqfactor       = _mm_xor_ps(signbit,_mm_mul_ps(qq00,_mm_mul_ps(isaprod,gbinvepsdiff)));
 685             gbscale          = _mm_mul_ps(isaprod,gbtabscale);
 686
 687             /* Calculate generalized born table index - this is a separate table from the normal one,
 688              * but we use the same procedure by multiplying r with scale and truncating to integer.
 689              */
 690             rt               = _mm_mul_ps(r00,gbscale);
 691             gbitab           = _mm_cvttps_epi32(rt);
 692             gbeps            = _mm_sub_ps(rt,_mm_cvtepi32_ps(gbitab));
 693             gbitab           = _mm_slli_epi32(gbitab,2);
 694
 695             Y                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,0) );
 696             F                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,1) );
 697             G                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,2) );
 698             H                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,3) );
 699             _MM_TRANSPOSE4_PS(Y,F,G,H);
 700             Heps             = _mm_mul_ps(gbeps,H);
 701             Fp               = _mm_add_ps(F,_mm_mul_ps(gbeps,_mm_add_ps(G,Heps)));
 702             VV               = _mm_add_ps(Y,_mm_mul_ps(gbeps,Fp));
 703             vgb              = _mm_mul_ps(gbqqfactor,VV);
 704
 705             FF               = _mm_add_ps(Fp,_mm_mul_ps(gbeps,_mm_add_ps(G,_mm_add_ps(Heps,Heps))));
 706             fgb              = _mm_mul_ps(gbqqfactor,_mm_mul_ps(FF,gbscale));
 707             dvdatmp          = _mm_mul_ps(minushalf,_mm_add_ps(vgb,_mm_mul_ps(fgb,r00)));
 708             dvdatmp          = _mm_andnot_ps(dummy_mask,dvdatmp);
 709             dvdasum          = _mm_add_ps(dvdasum,dvdatmp);
 710             /* 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. */
 711             fjptrA             = (jnrlistA>=0) ? dvda+jnrA : scratch;
 712             fjptrB             = (jnrlistB>=0) ? dvda+jnrB : scratch;
 713             fjptrC             = (jnrlistC>=0) ? dvda+jnrC : scratch;
 714             fjptrD             = (jnrlistD>=0) ? dvda+jnrD : scratch;
 715             gmx_mm_increment_4real_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,_mm_mul_ps(dvdatmp,_mm_mul_ps(isaj0,isaj0)));
 716             velec            = _mm_mul_ps(qq00,rinv00);
 717             felec            = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(velec,rinv00),fgb),rinv00);
 718
 719             fscal            = felec;
 720
 721             fscal            = _mm_andnot_ps(dummy_mask,fscal);
 722
 723             /* Calculate temporary vectorial force */
 724             tx               = _mm_mul_ps(fscal,dx00);
 725             ty               = _mm_mul_ps(fscal,dy00);
 726             tz               = _mm_mul_ps(fscal,dz00);
 727
 728             /* Update vectorial force */
 729             fix0             = _mm_add_ps(fix0,tx);
 730             fiy0             = _mm_add_ps(fiy0,ty);
 731             fiz0             = _mm_add_ps(fiz0,tz);
 732
 733             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
 734             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
 735             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
 736             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
 737             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 738
 739             /* Inner loop uses 57 flops */
 740         }
 741
 742         /* End of innermost loop */
 743
 744         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
 745                                               f+i_coord_offset,fshift+i_shift_offset);
 746
 747         dvdasum = _mm_mul_ps(dvdasum, _mm_mul_ps(isai0,isai0));
 748         gmx_mm_update_1pot_ps(dvdasum,dvda+inr);
 749
 750         /* Increment number of inner iterations */
 751         inneriter                  += j_index_end - j_index_start;
 752
 753         /* Outer loop uses 7 flops */
 754     }
 755
 756     /* Increment number of outer iterations */
 757     outeriter        += nri;
 758
 759     /* Update outer/inner flops */
 760
 761     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_F,outeriter*7 + inneriter*57);
 762 }