src/gromacs/gmxlib/nonbonded/nb_kernel_sse2_single/nb_kernel_ElecEwSh_VdwLJSh_GeomW3P1_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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  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 "types/simple.h"
  44 #include "gromacs/math/vec.h"
  45 #include "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_ElecEwSh_VdwLJSh_GeomW3P1_VF_sse2_single
  52  * Electrostatics interaction: Ewald
  53  * VdW interaction:            LennardJones
  54  * Geometry:                   Water3-Particle
  55  * Calculate force/pot:        PotentialAndForce
  56  */
  57 void
  58 nb_kernel_ElecEwSh_VdwLJSh_GeomW3P1_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              vdwioffset1;
  86     __m128           ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
  87     int              vdwioffset2;
  88     __m128           ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
  89     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
  90     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  91     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
  92     __m128           dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10;
  93     __m128           dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20;
  94     __m128           velec,felec,velecsum,facel,crf,krf,krf2;
  95     real             *charge;
  96     int              nvdwtype;
  97     __m128           rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
  98     int              *vdwtype;
  99     real             *vdwparam;
 100     __m128           one_sixth   = _mm_set1_ps(1.0/6.0);
 101     __m128           one_twelfth = _mm_set1_ps(1.0/12.0);
 102     __m128i          ewitab;
 103     __m128           ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace,ewtabF,ewtabFn,ewtabD,ewtabV;
 104     real             *ewtab;
 105     __m128           dummy_mask,cutoff_mask;
 106     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
 107     __m128           one     = _mm_set1_ps(1.0);
 108     __m128           two     = _mm_set1_ps(2.0);
 109     x                = xx[0];
 110     f                = ff[0];
 111
 112     nri              = nlist->nri;
 113     iinr             = nlist->iinr;
 114     jindex           = nlist->jindex;
 115     jjnr             = nlist->jjnr;
 116     shiftidx         = nlist->shift;
 117     gid              = nlist->gid;
 118     shiftvec         = fr->shift_vec[0];
 119     fshift           = fr->fshift[0];
 120     facel            = _mm_set1_ps(fr->epsfac);
 121     charge           = mdatoms->chargeA;
 122     nvdwtype         = fr->ntype;
 123     vdwparam         = fr->nbfp;
 124     vdwtype          = mdatoms->typeA;
 125
 126     sh_ewald         = _mm_set1_ps(fr->ic->sh_ewald);
 127     ewtab            = fr->ic->tabq_coul_FDV0;
 128     ewtabscale       = _mm_set1_ps(fr->ic->tabq_scale);
 129     ewtabhalfspace   = _mm_set1_ps(0.5/fr->ic->tabq_scale);
 130
 131     /* Setup water-specific parameters */
 132     inr              = nlist->iinr[0];
 133     iq0              = _mm_mul_ps(facel,_mm_set1_ps(charge[inr+0]));
 134     iq1              = _mm_mul_ps(facel,_mm_set1_ps(charge[inr+1]));
 135     iq2              = _mm_mul_ps(facel,_mm_set1_ps(charge[inr+2]));
 136     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 137
 138     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 139     rcutoff_scalar   = fr->rcoulomb;
 140     rcutoff          = _mm_set1_ps(rcutoff_scalar);
 141     rcutoff2         = _mm_mul_ps(rcutoff,rcutoff);
 142
 143     sh_vdw_invrcut6  = _mm_set1_ps(fr->ic->sh_invrc6);
 144     rvdw             = _mm_set1_ps(fr->rvdw);
 145
 146     /* Avoid stupid compiler warnings */
 147     jnrA = jnrB = jnrC = jnrD = 0;
 148     j_coord_offsetA = 0;
 149     j_coord_offsetB = 0;
 150     j_coord_offsetC = 0;
 151     j_coord_offsetD = 0;
 152
 153     outeriter        = 0;
 154     inneriter        = 0;
 155
 156     for(iidx=0;iidx<4*DIM;iidx++)
 157     {
 158         scratch[iidx] = 0.0;
 159     }
 160
 161     /* Start outer loop over neighborlists */
 162     for(iidx=0; iidx<nri; iidx++)
 163     {
 164         /* Load shift vector for this list */
 165         i_shift_offset   = DIM*shiftidx[iidx];
 166
 167         /* Load limits for loop over neighbors */
 168         j_index_start    = jindex[iidx];
 169         j_index_end      = jindex[iidx+1];
 170
 171         /* Get outer coordinate index */
 172         inr              = iinr[iidx];
 173         i_coord_offset   = DIM*inr;
 174
 175         /* Load i particle coords and add shift vector */
 176         gmx_mm_load_shift_and_3rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,
 177                                                  &ix0,&iy0,&iz0,&ix1,&iy1,&iz1,&ix2,&iy2,&iz2);
 178
 179         fix0             = _mm_setzero_ps();
 180         fiy0             = _mm_setzero_ps();
 181         fiz0             = _mm_setzero_ps();
 182         fix1             = _mm_setzero_ps();
 183         fiy1             = _mm_setzero_ps();
 184         fiz1             = _mm_setzero_ps();
 185         fix2             = _mm_setzero_ps();
 186         fiy2             = _mm_setzero_ps();
 187         fiz2             = _mm_setzero_ps();
 188
 189         /* Reset potential sums */
 190         velecsum         = _mm_setzero_ps();
 191         vvdwsum          = _mm_setzero_ps();
 192
 193         /* Start inner kernel loop */
 194         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
 195         {
 196
 197             /* Get j neighbor index, and coordinate index */
 198             jnrA             = jjnr[jidx];
 199             jnrB             = jjnr[jidx+1];
 200             jnrC             = jjnr[jidx+2];
 201             jnrD             = jjnr[jidx+3];
 202             j_coord_offsetA  = DIM*jnrA;
 203             j_coord_offsetB  = DIM*jnrB;
 204             j_coord_offsetC  = DIM*jnrC;
 205             j_coord_offsetD  = DIM*jnrD;
 206
 207             /* load j atom coordinates */
 208             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 209                                               x+j_coord_offsetC,x+j_coord_offsetD,
 210                                               &jx0,&jy0,&jz0);
 211
 212             /* Calculate displacement vector */
 213             dx00             = _mm_sub_ps(ix0,jx0);
 214             dy00             = _mm_sub_ps(iy0,jy0);
 215             dz00             = _mm_sub_ps(iz0,jz0);
 216             dx10             = _mm_sub_ps(ix1,jx0);
 217             dy10             = _mm_sub_ps(iy1,jy0);
 218             dz10             = _mm_sub_ps(iz1,jz0);
 219             dx20             = _mm_sub_ps(ix2,jx0);
 220             dy20             = _mm_sub_ps(iy2,jy0);
 221             dz20             = _mm_sub_ps(iz2,jz0);
 222
 223             /* Calculate squared distance and things based on it */
 224             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 225             rsq10            = gmx_mm_calc_rsq_ps(dx10,dy10,dz10);
 226             rsq20            = gmx_mm_calc_rsq_ps(dx20,dy20,dz20);
 227
 228             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 229             rinv10           = gmx_mm_invsqrt_ps(rsq10);
 230             rinv20           = gmx_mm_invsqrt_ps(rsq20);
 231
 232             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
 233             rinvsq10         = _mm_mul_ps(rinv10,rinv10);
 234             rinvsq20         = _mm_mul_ps(rinv20,rinv20);
 235
 236             /* Load parameters for j particles */
 237             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 238                                                               charge+jnrC+0,charge+jnrD+0);
 239             vdwjidx0A        = 2*vdwtype[jnrA+0];
 240             vdwjidx0B        = 2*vdwtype[jnrB+0];
 241             vdwjidx0C        = 2*vdwtype[jnrC+0];
 242             vdwjidx0D        = 2*vdwtype[jnrD+0];
 243
 244             fjx0             = _mm_setzero_ps();
 245             fjy0             = _mm_setzero_ps();
 246             fjz0             = _mm_setzero_ps();
 247
 248             /**************************
 249              * CALCULATE INTERACTIONS *
 250              **************************/
 251
 252             if (gmx_mm_any_lt(rsq00,rcutoff2))
 253             {
 254
 255             r00              = _mm_mul_ps(rsq00,rinv00);
 256
 257             /* Compute parameters for interactions between i and j atoms */
 258             qq00             = _mm_mul_ps(iq0,jq0);
 259             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
 260                                          vdwparam+vdwioffset0+vdwjidx0B,
 261                                          vdwparam+vdwioffset0+vdwjidx0C,
 262                                          vdwparam+vdwioffset0+vdwjidx0D,
 263                                          &c6_00,&c12_00);
 264
 265             /* EWALD ELECTROSTATICS */
 266
 267             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 268             ewrt             = _mm_mul_ps(r00,ewtabscale);
 269             ewitab           = _mm_cvttps_epi32(ewrt);
 270             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
 271             ewitab           = _mm_slli_epi32(ewitab,2);
 272             ewtabF           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,0) );
 273             ewtabD           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,1) );
 274             ewtabV           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,2) );
 275             ewtabFn          = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,3) );
 276             _MM_TRANSPOSE4_PS(ewtabF,ewtabD,ewtabV,ewtabFn);
 277             felec            = _mm_add_ps(ewtabF,_mm_mul_ps(eweps,ewtabD));
 278             velec            = _mm_sub_ps(ewtabV,_mm_mul_ps(_mm_mul_ps(ewtabhalfspace,eweps),_mm_add_ps(ewtabF,felec)));
 279             velec            = _mm_mul_ps(qq00,_mm_sub_ps(_mm_sub_ps(rinv00,sh_ewald),velec));
 280             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
 281
 282             /* LENNARD-JONES DISPERSION/REPULSION */
 283
 284             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
 285             vvdw6            = _mm_mul_ps(c6_00,rinvsix);
 286             vvdw12           = _mm_mul_ps(c12_00,_mm_mul_ps(rinvsix,rinvsix));
 287             vvdw             = _mm_sub_ps(_mm_mul_ps( _mm_sub_ps(vvdw12 , _mm_mul_ps(c12_00,_mm_mul_ps(sh_vdw_invrcut6,sh_vdw_invrcut6))), one_twelfth) ,
 288                                           _mm_mul_ps( _mm_sub_ps(vvdw6,_mm_mul_ps(c6_00,sh_vdw_invrcut6)),one_sixth));
 289             fvdw             = _mm_mul_ps(_mm_sub_ps(vvdw12,vvdw6),rinvsq00);
 290
 291             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
 292
 293             /* Update potential sum for this i atom from the interaction with this j atom. */
 294             velec            = _mm_and_ps(velec,cutoff_mask);
 295             velecsum         = _mm_add_ps(velecsum,velec);
 296             vvdw             = _mm_and_ps(vvdw,cutoff_mask);
 297             vvdwsum          = _mm_add_ps(vvdwsum,vvdw);
 298
 299             fscal            = _mm_add_ps(felec,fvdw);
 300
 301             fscal            = _mm_and_ps(fscal,cutoff_mask);
 302
 303             /* Calculate temporary vectorial force */
 304             tx               = _mm_mul_ps(fscal,dx00);
 305             ty               = _mm_mul_ps(fscal,dy00);
 306             tz               = _mm_mul_ps(fscal,dz00);
 307
 308             /* Update vectorial force */
 309             fix0             = _mm_add_ps(fix0,tx);
 310             fiy0             = _mm_add_ps(fiy0,ty);
 311             fiz0             = _mm_add_ps(fiz0,tz);
 312
 313             fjx0             = _mm_add_ps(fjx0,tx);
 314             fjy0             = _mm_add_ps(fjy0,ty);
 315             fjz0             = _mm_add_ps(fjz0,tz);
 316
 317             }
 318
 319             /**************************
 320              * CALCULATE INTERACTIONS *
 321              **************************/
 322
 323             if (gmx_mm_any_lt(rsq10,rcutoff2))
 324             {
 325
 326             r10              = _mm_mul_ps(rsq10,rinv10);
 327
 328             /* Compute parameters for interactions between i and j atoms */
 329             qq10             = _mm_mul_ps(iq1,jq0);
 330
 331             /* EWALD ELECTROSTATICS */
 332
 333             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 334             ewrt             = _mm_mul_ps(r10,ewtabscale);
 335             ewitab           = _mm_cvttps_epi32(ewrt);
 336             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
 337             ewitab           = _mm_slli_epi32(ewitab,2);
 338             ewtabF           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,0) );
 339             ewtabD           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,1) );
 340             ewtabV           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,2) );
 341             ewtabFn          = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,3) );
 342             _MM_TRANSPOSE4_PS(ewtabF,ewtabD,ewtabV,ewtabFn);
 343             felec            = _mm_add_ps(ewtabF,_mm_mul_ps(eweps,ewtabD));
 344             velec            = _mm_sub_ps(ewtabV,_mm_mul_ps(_mm_mul_ps(ewtabhalfspace,eweps),_mm_add_ps(ewtabF,felec)));
 345             velec            = _mm_mul_ps(qq10,_mm_sub_ps(_mm_sub_ps(rinv10,sh_ewald),velec));
 346             felec            = _mm_mul_ps(_mm_mul_ps(qq10,rinv10),_mm_sub_ps(rinvsq10,felec));
 347
 348             cutoff_mask      = _mm_cmplt_ps(rsq10,rcutoff2);
 349
 350             /* Update potential sum for this i atom from the interaction with this j atom. */
 351             velec            = _mm_and_ps(velec,cutoff_mask);
 352             velecsum         = _mm_add_ps(velecsum,velec);
 353
 354             fscal            = felec;
 355
 356             fscal            = _mm_and_ps(fscal,cutoff_mask);
 357
 358             /* Calculate temporary vectorial force */
 359             tx               = _mm_mul_ps(fscal,dx10);
 360             ty               = _mm_mul_ps(fscal,dy10);
 361             tz               = _mm_mul_ps(fscal,dz10);
 362
 363             /* Update vectorial force */
 364             fix1             = _mm_add_ps(fix1,tx);
 365             fiy1             = _mm_add_ps(fiy1,ty);
 366             fiz1             = _mm_add_ps(fiz1,tz);
 367
 368             fjx0             = _mm_add_ps(fjx0,tx);
 369             fjy0             = _mm_add_ps(fjy0,ty);
 370             fjz0             = _mm_add_ps(fjz0,tz);
 371
 372             }
 373
 374             /**************************
 375              * CALCULATE INTERACTIONS *
 376              **************************/
 377
 378             if (gmx_mm_any_lt(rsq20,rcutoff2))
 379             {
 380
 381             r20              = _mm_mul_ps(rsq20,rinv20);
 382
 383             /* Compute parameters for interactions between i and j atoms */
 384             qq20             = _mm_mul_ps(iq2,jq0);
 385
 386             /* EWALD ELECTROSTATICS */
 387
 388             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 389             ewrt             = _mm_mul_ps(r20,ewtabscale);
 390             ewitab           = _mm_cvttps_epi32(ewrt);
 391             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
 392             ewitab           = _mm_slli_epi32(ewitab,2);
 393             ewtabF           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,0) );
 394             ewtabD           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,1) );
 395             ewtabV           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,2) );
 396             ewtabFn          = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,3) );
 397             _MM_TRANSPOSE4_PS(ewtabF,ewtabD,ewtabV,ewtabFn);
 398             felec            = _mm_add_ps(ewtabF,_mm_mul_ps(eweps,ewtabD));
 399             velec            = _mm_sub_ps(ewtabV,_mm_mul_ps(_mm_mul_ps(ewtabhalfspace,eweps),_mm_add_ps(ewtabF,felec)));
 400             velec            = _mm_mul_ps(qq20,_mm_sub_ps(_mm_sub_ps(rinv20,sh_ewald),velec));
 401             felec            = _mm_mul_ps(_mm_mul_ps(qq20,rinv20),_mm_sub_ps(rinvsq20,felec));
 402
 403             cutoff_mask      = _mm_cmplt_ps(rsq20,rcutoff2);
 404
 405             /* Update potential sum for this i atom from the interaction with this j atom. */
 406             velec            = _mm_and_ps(velec,cutoff_mask);
 407             velecsum         = _mm_add_ps(velecsum,velec);
 408
 409             fscal            = felec;
 410
 411             fscal            = _mm_and_ps(fscal,cutoff_mask);
 412
 413             /* Calculate temporary vectorial force */
 414             tx               = _mm_mul_ps(fscal,dx20);
 415             ty               = _mm_mul_ps(fscal,dy20);
 416             tz               = _mm_mul_ps(fscal,dz20);
 417
 418             /* Update vectorial force */
 419             fix2             = _mm_add_ps(fix2,tx);
 420             fiy2             = _mm_add_ps(fiy2,ty);
 421             fiz2             = _mm_add_ps(fiz2,tz);
 422
 423             fjx0             = _mm_add_ps(fjx0,tx);
 424             fjy0             = _mm_add_ps(fjy0,ty);
 425             fjz0             = _mm_add_ps(fjz0,tz);
 426
 427             }
 428
 429             fjptrA             = f+j_coord_offsetA;
 430             fjptrB             = f+j_coord_offsetB;
 431             fjptrC             = f+j_coord_offsetC;
 432             fjptrD             = f+j_coord_offsetD;
 433
 434             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,fjx0,fjy0,fjz0);
 435
 436             /* Inner loop uses 156 flops */
 437         }
 438
 439         if(jidx<j_index_end)
 440         {
 441
 442             /* Get j neighbor index, and coordinate index */
 443             jnrlistA         = jjnr[jidx];
 444             jnrlistB         = jjnr[jidx+1];
 445             jnrlistC         = jjnr[jidx+2];
 446             jnrlistD         = jjnr[jidx+3];
 447             /* Sign of each element will be negative for non-real atoms.
 448              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
 449              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
 450              */
 451             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
 452             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
 453             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
 454             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
 455             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
 456             j_coord_offsetA  = DIM*jnrA;
 457             j_coord_offsetB  = DIM*jnrB;
 458             j_coord_offsetC  = DIM*jnrC;
 459             j_coord_offsetD  = DIM*jnrD;
 460
 461             /* load j atom coordinates */
 462             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 463                                               x+j_coord_offsetC,x+j_coord_offsetD,
 464                                               &jx0,&jy0,&jz0);
 465
 466             /* Calculate displacement vector */
 467             dx00             = _mm_sub_ps(ix0,jx0);
 468             dy00             = _mm_sub_ps(iy0,jy0);
 469             dz00             = _mm_sub_ps(iz0,jz0);
 470             dx10             = _mm_sub_ps(ix1,jx0);
 471             dy10             = _mm_sub_ps(iy1,jy0);
 472             dz10             = _mm_sub_ps(iz1,jz0);
 473             dx20             = _mm_sub_ps(ix2,jx0);
 474             dy20             = _mm_sub_ps(iy2,jy0);
 475             dz20             = _mm_sub_ps(iz2,jz0);
 476
 477             /* Calculate squared distance and things based on it */
 478             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 479             rsq10            = gmx_mm_calc_rsq_ps(dx10,dy10,dz10);
 480             rsq20            = gmx_mm_calc_rsq_ps(dx20,dy20,dz20);
 481
 482             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 483             rinv10           = gmx_mm_invsqrt_ps(rsq10);
 484             rinv20           = gmx_mm_invsqrt_ps(rsq20);
 485
 486             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
 487             rinvsq10         = _mm_mul_ps(rinv10,rinv10);
 488             rinvsq20         = _mm_mul_ps(rinv20,rinv20);
 489
 490             /* Load parameters for j particles */
 491             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 492                                                               charge+jnrC+0,charge+jnrD+0);
 493             vdwjidx0A        = 2*vdwtype[jnrA+0];
 494             vdwjidx0B        = 2*vdwtype[jnrB+0];
 495             vdwjidx0C        = 2*vdwtype[jnrC+0];
 496             vdwjidx0D        = 2*vdwtype[jnrD+0];
 497
 498             fjx0             = _mm_setzero_ps();
 499             fjy0             = _mm_setzero_ps();
 500             fjz0             = _mm_setzero_ps();
 501
 502             /**************************
 503              * CALCULATE INTERACTIONS *
 504              **************************/
 505
 506             if (gmx_mm_any_lt(rsq00,rcutoff2))
 507             {
 508
 509             r00              = _mm_mul_ps(rsq00,rinv00);
 510             r00              = _mm_andnot_ps(dummy_mask,r00);
 511
 512             /* Compute parameters for interactions between i and j atoms */
 513             qq00             = _mm_mul_ps(iq0,jq0);
 514             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
 515                                          vdwparam+vdwioffset0+vdwjidx0B,
 516                                          vdwparam+vdwioffset0+vdwjidx0C,
 517                                          vdwparam+vdwioffset0+vdwjidx0D,
 518                                          &c6_00,&c12_00);
 519
 520             /* EWALD ELECTROSTATICS */
 521
 522             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 523             ewrt             = _mm_mul_ps(r00,ewtabscale);
 524             ewitab           = _mm_cvttps_epi32(ewrt);
 525             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
 526             ewitab           = _mm_slli_epi32(ewitab,2);
 527             ewtabF           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,0) );
 528             ewtabD           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,1) );
 529             ewtabV           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,2) );
 530             ewtabFn          = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,3) );
 531             _MM_TRANSPOSE4_PS(ewtabF,ewtabD,ewtabV,ewtabFn);
 532             felec            = _mm_add_ps(ewtabF,_mm_mul_ps(eweps,ewtabD));
 533             velec            = _mm_sub_ps(ewtabV,_mm_mul_ps(_mm_mul_ps(ewtabhalfspace,eweps),_mm_add_ps(ewtabF,felec)));
 534             velec            = _mm_mul_ps(qq00,_mm_sub_ps(_mm_sub_ps(rinv00,sh_ewald),velec));
 535             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
 536
 537             /* LENNARD-JONES DISPERSION/REPULSION */
 538
 539             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
 540             vvdw6            = _mm_mul_ps(c6_00,rinvsix);
 541             vvdw12           = _mm_mul_ps(c12_00,_mm_mul_ps(rinvsix,rinvsix));
 542             vvdw             = _mm_sub_ps(_mm_mul_ps( _mm_sub_ps(vvdw12 , _mm_mul_ps(c12_00,_mm_mul_ps(sh_vdw_invrcut6,sh_vdw_invrcut6))), one_twelfth) ,
 543                                           _mm_mul_ps( _mm_sub_ps(vvdw6,_mm_mul_ps(c6_00,sh_vdw_invrcut6)),one_sixth));
 544             fvdw             = _mm_mul_ps(_mm_sub_ps(vvdw12,vvdw6),rinvsq00);
 545
 546             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
 547
 548             /* Update potential sum for this i atom from the interaction with this j atom. */
 549             velec            = _mm_and_ps(velec,cutoff_mask);
 550             velec            = _mm_andnot_ps(dummy_mask,velec);
 551             velecsum         = _mm_add_ps(velecsum,velec);
 552             vvdw             = _mm_and_ps(vvdw,cutoff_mask);
 553             vvdw             = _mm_andnot_ps(dummy_mask,vvdw);
 554             vvdwsum          = _mm_add_ps(vvdwsum,vvdw);
 555
 556             fscal            = _mm_add_ps(felec,fvdw);
 557
 558             fscal            = _mm_and_ps(fscal,cutoff_mask);
 559
 560             fscal            = _mm_andnot_ps(dummy_mask,fscal);
 561
 562             /* Calculate temporary vectorial force */
 563             tx               = _mm_mul_ps(fscal,dx00);
 564             ty               = _mm_mul_ps(fscal,dy00);
 565             tz               = _mm_mul_ps(fscal,dz00);
 566
 567             /* Update vectorial force */
 568             fix0             = _mm_add_ps(fix0,tx);
 569             fiy0             = _mm_add_ps(fiy0,ty);
 570             fiz0             = _mm_add_ps(fiz0,tz);
 571
 572             fjx0             = _mm_add_ps(fjx0,tx);
 573             fjy0             = _mm_add_ps(fjy0,ty);
 574             fjz0             = _mm_add_ps(fjz0,tz);
 575
 576             }
 577
 578             /**************************
 579              * CALCULATE INTERACTIONS *
 580              **************************/
 581
 582             if (gmx_mm_any_lt(rsq10,rcutoff2))
 583             {
 584
 585             r10              = _mm_mul_ps(rsq10,rinv10);
 586             r10              = _mm_andnot_ps(dummy_mask,r10);
 587
 588             /* Compute parameters for interactions between i and j atoms */
 589             qq10             = _mm_mul_ps(iq1,jq0);
 590
 591             /* EWALD ELECTROSTATICS */
 592
 593             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 594             ewrt             = _mm_mul_ps(r10,ewtabscale);
 595             ewitab           = _mm_cvttps_epi32(ewrt);
 596             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
 597             ewitab           = _mm_slli_epi32(ewitab,2);
 598             ewtabF           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,0) );
 599             ewtabD           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,1) );
 600             ewtabV           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,2) );
 601             ewtabFn          = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,3) );
 602             _MM_TRANSPOSE4_PS(ewtabF,ewtabD,ewtabV,ewtabFn);
 603             felec            = _mm_add_ps(ewtabF,_mm_mul_ps(eweps,ewtabD));
 604             velec            = _mm_sub_ps(ewtabV,_mm_mul_ps(_mm_mul_ps(ewtabhalfspace,eweps),_mm_add_ps(ewtabF,felec)));
 605             velec            = _mm_mul_ps(qq10,_mm_sub_ps(_mm_sub_ps(rinv10,sh_ewald),velec));
 606             felec            = _mm_mul_ps(_mm_mul_ps(qq10,rinv10),_mm_sub_ps(rinvsq10,felec));
 607
 608             cutoff_mask      = _mm_cmplt_ps(rsq10,rcutoff2);
 609
 610             /* Update potential sum for this i atom from the interaction with this j atom. */
 611             velec            = _mm_and_ps(velec,cutoff_mask);
 612             velec            = _mm_andnot_ps(dummy_mask,velec);
 613             velecsum         = _mm_add_ps(velecsum,velec);
 614
 615             fscal            = felec;
 616
 617             fscal            = _mm_and_ps(fscal,cutoff_mask);
 618
 619             fscal            = _mm_andnot_ps(dummy_mask,fscal);
 620
 621             /* Calculate temporary vectorial force */
 622             tx               = _mm_mul_ps(fscal,dx10);
 623             ty               = _mm_mul_ps(fscal,dy10);
 624             tz               = _mm_mul_ps(fscal,dz10);
 625
 626             /* Update vectorial force */
 627             fix1             = _mm_add_ps(fix1,tx);
 628             fiy1             = _mm_add_ps(fiy1,ty);
 629             fiz1             = _mm_add_ps(fiz1,tz);
 630
 631             fjx0             = _mm_add_ps(fjx0,tx);
 632             fjy0             = _mm_add_ps(fjy0,ty);
 633             fjz0             = _mm_add_ps(fjz0,tz);
 634
 635             }
 636
 637             /**************************
 638              * CALCULATE INTERACTIONS *
 639              **************************/
 640
 641             if (gmx_mm_any_lt(rsq20,rcutoff2))
 642             {
 643
 644             r20              = _mm_mul_ps(rsq20,rinv20);
 645             r20              = _mm_andnot_ps(dummy_mask,r20);
 646
 647             /* Compute parameters for interactions between i and j atoms */
 648             qq20             = _mm_mul_ps(iq2,jq0);
 649
 650             /* EWALD ELECTROSTATICS */
 651
 652             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 653             ewrt             = _mm_mul_ps(r20,ewtabscale);
 654             ewitab           = _mm_cvttps_epi32(ewrt);
 655             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
 656             ewitab           = _mm_slli_epi32(ewitab,2);
 657             ewtabF           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,0) );
 658             ewtabD           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,1) );
 659             ewtabV           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,2) );
 660             ewtabFn          = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,3) );
 661             _MM_TRANSPOSE4_PS(ewtabF,ewtabD,ewtabV,ewtabFn);
 662             felec            = _mm_add_ps(ewtabF,_mm_mul_ps(eweps,ewtabD));
 663             velec            = _mm_sub_ps(ewtabV,_mm_mul_ps(_mm_mul_ps(ewtabhalfspace,eweps),_mm_add_ps(ewtabF,felec)));
 664             velec            = _mm_mul_ps(qq20,_mm_sub_ps(_mm_sub_ps(rinv20,sh_ewald),velec));
 665             felec            = _mm_mul_ps(_mm_mul_ps(qq20,rinv20),_mm_sub_ps(rinvsq20,felec));
 666
 667             cutoff_mask      = _mm_cmplt_ps(rsq20,rcutoff2);
 668
 669             /* Update potential sum for this i atom from the interaction with this j atom. */
 670             velec            = _mm_and_ps(velec,cutoff_mask);
 671             velec            = _mm_andnot_ps(dummy_mask,velec);
 672             velecsum         = _mm_add_ps(velecsum,velec);
 673
 674             fscal            = felec;
 675
 676             fscal            = _mm_and_ps(fscal,cutoff_mask);
 677
 678             fscal            = _mm_andnot_ps(dummy_mask,fscal);
 679
 680             /* Calculate temporary vectorial force */
 681             tx               = _mm_mul_ps(fscal,dx20);
 682             ty               = _mm_mul_ps(fscal,dy20);
 683             tz               = _mm_mul_ps(fscal,dz20);
 684
 685             /* Update vectorial force */
 686             fix2             = _mm_add_ps(fix2,tx);
 687             fiy2             = _mm_add_ps(fiy2,ty);
 688             fiz2             = _mm_add_ps(fiz2,tz);
 689
 690             fjx0             = _mm_add_ps(fjx0,tx);
 691             fjy0             = _mm_add_ps(fjy0,ty);
 692             fjz0             = _mm_add_ps(fjz0,tz);
 693
 694             }
 695
 696             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
 697             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
 698             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
 699             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
 700
 701             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,fjx0,fjy0,fjz0);
 702
 703             /* Inner loop uses 159 flops */
 704         }
 705
 706         /* End of innermost loop */
 707
 708         gmx_mm_update_iforce_3atom_swizzle_ps(fix0,fiy0,fiz0,fix1,fiy1,fiz1,fix2,fiy2,fiz2,
 709                                               f+i_coord_offset,fshift+i_shift_offset);
 710
 711         ggid                        = gid[iidx];
 712         /* Update potential energies */
 713         gmx_mm_update_1pot_ps(velecsum,kernel_data->energygrp_elec+ggid);
 714         gmx_mm_update_1pot_ps(vvdwsum,kernel_data->energygrp_vdw+ggid);
 715
 716         /* Increment number of inner iterations */
 717         inneriter                  += j_index_end - j_index_start;
 718
 719         /* Outer loop uses 20 flops */
 720     }
 721
 722     /* Increment number of outer iterations */
 723     outeriter        += nri;
 724
 725     /* Update outer/inner flops */
 726
 727     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W3_VF,outeriter*20 + inneriter*159);
 728 }
 729 /*
 730  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSh_VdwLJSh_GeomW3P1_F_sse2_single
 731  * Electrostatics interaction: Ewald
 732  * VdW interaction:            LennardJones
 733  * Geometry:                   Water3-Particle
 734  * Calculate force/pot:        Force
 735  */
 736 void
 737 nb_kernel_ElecEwSh_VdwLJSh_GeomW3P1_F_sse2_single
 738                     (t_nblist                    * gmx_restrict       nlist,
 739                      rvec                        * gmx_restrict          xx,
 740                      rvec                        * gmx_restrict          ff,
 741                      t_forcerec                  * gmx_restrict          fr,
 742                      t_mdatoms                   * gmx_restrict     mdatoms,
 743                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 744                      t_nrnb                      * gmx_restrict        nrnb)
 745 {
 746     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
 747      * just 0 for non-waters.
 748      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
 749      * jnr indices corresponding to data put in the four positions in the SIMD register.
 750      */
 751     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
 752     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
 753     int              jnrA,jnrB,jnrC,jnrD;
 754     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
 755     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
 756     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 757     real             rcutoff_scalar;
 758     real             *shiftvec,*fshift,*x,*f;
 759     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
 760     real             scratch[4*DIM];
 761     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
 762     int              vdwioffset0;
 763     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 764     int              vdwioffset1;
 765     __m128           ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 766     int              vdwioffset2;
 767     __m128           ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 768     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
 769     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 770     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
 771     __m128           dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10;
 772     __m128           dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20;
 773     __m128           velec,felec,velecsum,facel,crf,krf,krf2;
 774     real             *charge;
 775     int              nvdwtype;
 776     __m128           rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
 777     int              *vdwtype;
 778     real             *vdwparam;
 779     __m128           one_sixth   = _mm_set1_ps(1.0/6.0);
 780     __m128           one_twelfth = _mm_set1_ps(1.0/12.0);
 781     __m128i          ewitab;
 782     __m128           ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace,ewtabF,ewtabFn,ewtabD,ewtabV;
 783     real             *ewtab;
 784     __m128           dummy_mask,cutoff_mask;
 785     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
 786     __m128           one     = _mm_set1_ps(1.0);
 787     __m128           two     = _mm_set1_ps(2.0);
 788     x                = xx[0];
 789     f                = ff[0];
 790
 791     nri              = nlist->nri;
 792     iinr             = nlist->iinr;
 793     jindex           = nlist->jindex;
 794     jjnr             = nlist->jjnr;
 795     shiftidx         = nlist->shift;
 796     gid              = nlist->gid;
 797     shiftvec         = fr->shift_vec[0];
 798     fshift           = fr->fshift[0];
 799     facel            = _mm_set1_ps(fr->epsfac);
 800     charge           = mdatoms->chargeA;
 801     nvdwtype         = fr->ntype;
 802     vdwparam         = fr->nbfp;
 803     vdwtype          = mdatoms->typeA;
 804
 805     sh_ewald         = _mm_set1_ps(fr->ic->sh_ewald);
 806     ewtab            = fr->ic->tabq_coul_F;
 807     ewtabscale       = _mm_set1_ps(fr->ic->tabq_scale);
 808     ewtabhalfspace   = _mm_set1_ps(0.5/fr->ic->tabq_scale);
 809
 810     /* Setup water-specific parameters */
 811     inr              = nlist->iinr[0];
 812     iq0              = _mm_mul_ps(facel,_mm_set1_ps(charge[inr+0]));
 813     iq1              = _mm_mul_ps(facel,_mm_set1_ps(charge[inr+1]));
 814     iq2              = _mm_mul_ps(facel,_mm_set1_ps(charge[inr+2]));
 815     vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 816
 817     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 818     rcutoff_scalar   = fr->rcoulomb;
 819     rcutoff          = _mm_set1_ps(rcutoff_scalar);
 820     rcutoff2         = _mm_mul_ps(rcutoff,rcutoff);
 821
 822     sh_vdw_invrcut6  = _mm_set1_ps(fr->ic->sh_invrc6);
 823     rvdw             = _mm_set1_ps(fr->rvdw);
 824
 825     /* Avoid stupid compiler warnings */
 826     jnrA = jnrB = jnrC = jnrD = 0;
 827     j_coord_offsetA = 0;
 828     j_coord_offsetB = 0;
 829     j_coord_offsetC = 0;
 830     j_coord_offsetD = 0;
 831
 832     outeriter        = 0;
 833     inneriter        = 0;
 834
 835     for(iidx=0;iidx<4*DIM;iidx++)
 836     {
 837         scratch[iidx] = 0.0;
 838     }
 839
 840     /* Start outer loop over neighborlists */
 841     for(iidx=0; iidx<nri; iidx++)
 842     {
 843         /* Load shift vector for this list */
 844         i_shift_offset   = DIM*shiftidx[iidx];
 845
 846         /* Load limits for loop over neighbors */
 847         j_index_start    = jindex[iidx];
 848         j_index_end      = jindex[iidx+1];
 849
 850         /* Get outer coordinate index */
 851         inr              = iinr[iidx];
 852         i_coord_offset   = DIM*inr;
 853
 854         /* Load i particle coords and add shift vector */
 855         gmx_mm_load_shift_and_3rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,
 856                                                  &ix0,&iy0,&iz0,&ix1,&iy1,&iz1,&ix2,&iy2,&iz2);
 857
 858         fix0             = _mm_setzero_ps();
 859         fiy0             = _mm_setzero_ps();
 860         fiz0             = _mm_setzero_ps();
 861         fix1             = _mm_setzero_ps();
 862         fiy1             = _mm_setzero_ps();
 863         fiz1             = _mm_setzero_ps();
 864         fix2             = _mm_setzero_ps();
 865         fiy2             = _mm_setzero_ps();
 866         fiz2             = _mm_setzero_ps();
 867
 868         /* Start inner kernel loop */
 869         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
 870         {
 871
 872             /* Get j neighbor index, and coordinate index */
 873             jnrA             = jjnr[jidx];
 874             jnrB             = jjnr[jidx+1];
 875             jnrC             = jjnr[jidx+2];
 876             jnrD             = jjnr[jidx+3];
 877             j_coord_offsetA  = DIM*jnrA;
 878             j_coord_offsetB  = DIM*jnrB;
 879             j_coord_offsetC  = DIM*jnrC;
 880             j_coord_offsetD  = DIM*jnrD;
 881
 882             /* load j atom coordinates */
 883             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 884                                               x+j_coord_offsetC,x+j_coord_offsetD,
 885                                               &jx0,&jy0,&jz0);
 886
 887             /* Calculate displacement vector */
 888             dx00             = _mm_sub_ps(ix0,jx0);
 889             dy00             = _mm_sub_ps(iy0,jy0);
 890             dz00             = _mm_sub_ps(iz0,jz0);
 891             dx10             = _mm_sub_ps(ix1,jx0);
 892             dy10             = _mm_sub_ps(iy1,jy0);
 893             dz10             = _mm_sub_ps(iz1,jz0);
 894             dx20             = _mm_sub_ps(ix2,jx0);
 895             dy20             = _mm_sub_ps(iy2,jy0);
 896             dz20             = _mm_sub_ps(iz2,jz0);
 897
 898             /* Calculate squared distance and things based on it */
 899             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 900             rsq10            = gmx_mm_calc_rsq_ps(dx10,dy10,dz10);
 901             rsq20            = gmx_mm_calc_rsq_ps(dx20,dy20,dz20);
 902
 903             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 904             rinv10           = gmx_mm_invsqrt_ps(rsq10);
 905             rinv20           = gmx_mm_invsqrt_ps(rsq20);
 906
 907             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
 908             rinvsq10         = _mm_mul_ps(rinv10,rinv10);
 909             rinvsq20         = _mm_mul_ps(rinv20,rinv20);
 910
 911             /* Load parameters for j particles */
 912             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
 913                                                               charge+jnrC+0,charge+jnrD+0);
 914             vdwjidx0A        = 2*vdwtype[jnrA+0];
 915             vdwjidx0B        = 2*vdwtype[jnrB+0];
 916             vdwjidx0C        = 2*vdwtype[jnrC+0];
 917             vdwjidx0D        = 2*vdwtype[jnrD+0];
 918
 919             fjx0             = _mm_setzero_ps();
 920             fjy0             = _mm_setzero_ps();
 921             fjz0             = _mm_setzero_ps();
 922
 923             /**************************
 924              * CALCULATE INTERACTIONS *
 925              **************************/
 926
 927             if (gmx_mm_any_lt(rsq00,rcutoff2))
 928             {
 929
 930             r00              = _mm_mul_ps(rsq00,rinv00);
 931
 932             /* Compute parameters for interactions between i and j atoms */
 933             qq00             = _mm_mul_ps(iq0,jq0);
 934             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
 935                                          vdwparam+vdwioffset0+vdwjidx0B,
 936                                          vdwparam+vdwioffset0+vdwjidx0C,
 937                                          vdwparam+vdwioffset0+vdwjidx0D,
 938                                          &c6_00,&c12_00);
 939
 940             /* EWALD ELECTROSTATICS */
 941
 942             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 943             ewrt             = _mm_mul_ps(r00,ewtabscale);
 944             ewitab           = _mm_cvttps_epi32(ewrt);
 945             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
 946             gmx_mm_load_4pair_swizzle_ps(ewtab+gmx_mm_extract_epi32(ewitab,0),ewtab+gmx_mm_extract_epi32(ewitab,1),
 947                                          ewtab+gmx_mm_extract_epi32(ewitab,2),ewtab+gmx_mm_extract_epi32(ewitab,3),
 948                                          &ewtabF,&ewtabFn);
 949             felec            = _mm_add_ps(_mm_mul_ps( _mm_sub_ps(one,eweps),ewtabF),_mm_mul_ps(eweps,ewtabFn));
 950             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
 951
 952             /* LENNARD-JONES DISPERSION/REPULSION */
 953
 954             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
 955             fvdw             = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(c12_00,rinvsix),c6_00),_mm_mul_ps(rinvsix,rinvsq00));
 956
 957             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
 958
 959             fscal            = _mm_add_ps(felec,fvdw);
 960
 961             fscal            = _mm_and_ps(fscal,cutoff_mask);
 962
 963             /* Calculate temporary vectorial force */
 964             tx               = _mm_mul_ps(fscal,dx00);
 965             ty               = _mm_mul_ps(fscal,dy00);
 966             tz               = _mm_mul_ps(fscal,dz00);
 967
 968             /* Update vectorial force */
 969             fix0             = _mm_add_ps(fix0,tx);
 970             fiy0             = _mm_add_ps(fiy0,ty);
 971             fiz0             = _mm_add_ps(fiz0,tz);
 972
 973             fjx0             = _mm_add_ps(fjx0,tx);
 974             fjy0             = _mm_add_ps(fjy0,ty);
 975             fjz0             = _mm_add_ps(fjz0,tz);
 976
 977             }
 978
 979             /**************************
 980              * CALCULATE INTERACTIONS *
 981              **************************/
 982
 983             if (gmx_mm_any_lt(rsq10,rcutoff2))
 984             {
 985
 986             r10              = _mm_mul_ps(rsq10,rinv10);
 987
 988             /* Compute parameters for interactions between i and j atoms */
 989             qq10             = _mm_mul_ps(iq1,jq0);
 990
 991             /* EWALD ELECTROSTATICS */
 992
 993             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
 994             ewrt             = _mm_mul_ps(r10,ewtabscale);
 995             ewitab           = _mm_cvttps_epi32(ewrt);
 996             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
 997             gmx_mm_load_4pair_swizzle_ps(ewtab+gmx_mm_extract_epi32(ewitab,0),ewtab+gmx_mm_extract_epi32(ewitab,1),
 998                                          ewtab+gmx_mm_extract_epi32(ewitab,2),ewtab+gmx_mm_extract_epi32(ewitab,3),
 999                                          &ewtabF,&ewtabFn);
1000             felec            = _mm_add_ps(_mm_mul_ps( _mm_sub_ps(one,eweps),ewtabF),_mm_mul_ps(eweps,ewtabFn));
1001             felec            = _mm_mul_ps(_mm_mul_ps(qq10,rinv10),_mm_sub_ps(rinvsq10,felec));
1002
1003             cutoff_mask      = _mm_cmplt_ps(rsq10,rcutoff2);
1004
1005             fscal            = felec;
1006
1007             fscal            = _mm_and_ps(fscal,cutoff_mask);
1008
1009             /* Calculate temporary vectorial force */
1010             tx               = _mm_mul_ps(fscal,dx10);
1011             ty               = _mm_mul_ps(fscal,dy10);
1012             tz               = _mm_mul_ps(fscal,dz10);
1013
1014             /* Update vectorial force */
1015             fix1             = _mm_add_ps(fix1,tx);
1016             fiy1             = _mm_add_ps(fiy1,ty);
1017             fiz1             = _mm_add_ps(fiz1,tz);
1018
1019             fjx0             = _mm_add_ps(fjx0,tx);
1020             fjy0             = _mm_add_ps(fjy0,ty);
1021             fjz0             = _mm_add_ps(fjz0,tz);
1022
1023             }
1024
1025             /**************************
1026              * CALCULATE INTERACTIONS *
1027              **************************/
1028
1029             if (gmx_mm_any_lt(rsq20,rcutoff2))
1030             {
1031
1032             r20              = _mm_mul_ps(rsq20,rinv20);
1033
1034             /* Compute parameters for interactions between i and j atoms */
1035             qq20             = _mm_mul_ps(iq2,jq0);
1036
1037             /* EWALD ELECTROSTATICS */
1038
1039             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1040             ewrt             = _mm_mul_ps(r20,ewtabscale);
1041             ewitab           = _mm_cvttps_epi32(ewrt);
1042             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
1043             gmx_mm_load_4pair_swizzle_ps(ewtab+gmx_mm_extract_epi32(ewitab,0),ewtab+gmx_mm_extract_epi32(ewitab,1),
1044                                          ewtab+gmx_mm_extract_epi32(ewitab,2),ewtab+gmx_mm_extract_epi32(ewitab,3),
1045                                          &ewtabF,&ewtabFn);
1046             felec            = _mm_add_ps(_mm_mul_ps( _mm_sub_ps(one,eweps),ewtabF),_mm_mul_ps(eweps,ewtabFn));
1047             felec            = _mm_mul_ps(_mm_mul_ps(qq20,rinv20),_mm_sub_ps(rinvsq20,felec));
1048
1049             cutoff_mask      = _mm_cmplt_ps(rsq20,rcutoff2);
1050
1051             fscal            = felec;
1052
1053             fscal            = _mm_and_ps(fscal,cutoff_mask);
1054
1055             /* Calculate temporary vectorial force */
1056             tx               = _mm_mul_ps(fscal,dx20);
1057             ty               = _mm_mul_ps(fscal,dy20);
1058             tz               = _mm_mul_ps(fscal,dz20);
1059
1060             /* Update vectorial force */
1061             fix2             = _mm_add_ps(fix2,tx);
1062             fiy2             = _mm_add_ps(fiy2,ty);
1063             fiz2             = _mm_add_ps(fiz2,tz);
1064
1065             fjx0             = _mm_add_ps(fjx0,tx);
1066             fjy0             = _mm_add_ps(fjy0,ty);
1067             fjz0             = _mm_add_ps(fjz0,tz);
1068
1069             }
1070
1071             fjptrA             = f+j_coord_offsetA;
1072             fjptrB             = f+j_coord_offsetB;
1073             fjptrC             = f+j_coord_offsetC;
1074             fjptrD             = f+j_coord_offsetD;
1075
1076             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,fjx0,fjy0,fjz0);
1077
1078             /* Inner loop uses 124 flops */
1079         }
1080
1081         if(jidx<j_index_end)
1082         {
1083
1084             /* Get j neighbor index, and coordinate index */
1085             jnrlistA         = jjnr[jidx];
1086             jnrlistB         = jjnr[jidx+1];
1087             jnrlistC         = jjnr[jidx+2];
1088             jnrlistD         = jjnr[jidx+3];
1089             /* Sign of each element will be negative for non-real atoms.
1090              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
1091              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
1092              */
1093             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
1094             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
1095             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
1096             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
1097             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
1098             j_coord_offsetA  = DIM*jnrA;
1099             j_coord_offsetB  = DIM*jnrB;
1100             j_coord_offsetC  = DIM*jnrC;
1101             j_coord_offsetD  = DIM*jnrD;
1102
1103             /* load j atom coordinates */
1104             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
1105                                               x+j_coord_offsetC,x+j_coord_offsetD,
1106                                               &jx0,&jy0,&jz0);
1107
1108             /* Calculate displacement vector */
1109             dx00             = _mm_sub_ps(ix0,jx0);
1110             dy00             = _mm_sub_ps(iy0,jy0);
1111             dz00             = _mm_sub_ps(iz0,jz0);
1112             dx10             = _mm_sub_ps(ix1,jx0);
1113             dy10             = _mm_sub_ps(iy1,jy0);
1114             dz10             = _mm_sub_ps(iz1,jz0);
1115             dx20             = _mm_sub_ps(ix2,jx0);
1116             dy20             = _mm_sub_ps(iy2,jy0);
1117             dz20             = _mm_sub_ps(iz2,jz0);
1118
1119             /* Calculate squared distance and things based on it */
1120             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
1121             rsq10            = gmx_mm_calc_rsq_ps(dx10,dy10,dz10);
1122             rsq20            = gmx_mm_calc_rsq_ps(dx20,dy20,dz20);
1123
1124             rinv00           = gmx_mm_invsqrt_ps(rsq00);
1125             rinv10           = gmx_mm_invsqrt_ps(rsq10);
1126             rinv20           = gmx_mm_invsqrt_ps(rsq20);
1127
1128             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
1129             rinvsq10         = _mm_mul_ps(rinv10,rinv10);
1130             rinvsq20         = _mm_mul_ps(rinv20,rinv20);
1131
1132             /* Load parameters for j particles */
1133             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
1134                                                               charge+jnrC+0,charge+jnrD+0);
1135             vdwjidx0A        = 2*vdwtype[jnrA+0];
1136             vdwjidx0B        = 2*vdwtype[jnrB+0];
1137             vdwjidx0C        = 2*vdwtype[jnrC+0];
1138             vdwjidx0D        = 2*vdwtype[jnrD+0];
1139
1140             fjx0             = _mm_setzero_ps();
1141             fjy0             = _mm_setzero_ps();
1142             fjz0             = _mm_setzero_ps();
1143
1144             /**************************
1145              * CALCULATE INTERACTIONS *
1146              **************************/
1147
1148             if (gmx_mm_any_lt(rsq00,rcutoff2))
1149             {
1150
1151             r00              = _mm_mul_ps(rsq00,rinv00);
1152             r00              = _mm_andnot_ps(dummy_mask,r00);
1153
1154             /* Compute parameters for interactions between i and j atoms */
1155             qq00             = _mm_mul_ps(iq0,jq0);
1156             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
1157                                          vdwparam+vdwioffset0+vdwjidx0B,
1158                                          vdwparam+vdwioffset0+vdwjidx0C,
1159                                          vdwparam+vdwioffset0+vdwjidx0D,
1160                                          &c6_00,&c12_00);
1161
1162             /* EWALD ELECTROSTATICS */
1163
1164             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1165             ewrt             = _mm_mul_ps(r00,ewtabscale);
1166             ewitab           = _mm_cvttps_epi32(ewrt);
1167             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
1168             gmx_mm_load_4pair_swizzle_ps(ewtab+gmx_mm_extract_epi32(ewitab,0),ewtab+gmx_mm_extract_epi32(ewitab,1),
1169                                          ewtab+gmx_mm_extract_epi32(ewitab,2),ewtab+gmx_mm_extract_epi32(ewitab,3),
1170                                          &ewtabF,&ewtabFn);
1171             felec            = _mm_add_ps(_mm_mul_ps( _mm_sub_ps(one,eweps),ewtabF),_mm_mul_ps(eweps,ewtabFn));
1172             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
1173
1174             /* LENNARD-JONES DISPERSION/REPULSION */
1175
1176             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
1177             fvdw             = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(c12_00,rinvsix),c6_00),_mm_mul_ps(rinvsix,rinvsq00));
1178
1179             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
1180
1181             fscal            = _mm_add_ps(felec,fvdw);
1182
1183             fscal            = _mm_and_ps(fscal,cutoff_mask);
1184
1185             fscal            = _mm_andnot_ps(dummy_mask,fscal);
1186
1187             /* Calculate temporary vectorial force */
1188             tx               = _mm_mul_ps(fscal,dx00);
1189             ty               = _mm_mul_ps(fscal,dy00);
1190             tz               = _mm_mul_ps(fscal,dz00);
1191
1192             /* Update vectorial force */
1193             fix0             = _mm_add_ps(fix0,tx);
1194             fiy0             = _mm_add_ps(fiy0,ty);
1195             fiz0             = _mm_add_ps(fiz0,tz);
1196
1197             fjx0             = _mm_add_ps(fjx0,tx);
1198             fjy0             = _mm_add_ps(fjy0,ty);
1199             fjz0             = _mm_add_ps(fjz0,tz);
1200
1201             }
1202
1203             /**************************
1204              * CALCULATE INTERACTIONS *
1205              **************************/
1206
1207             if (gmx_mm_any_lt(rsq10,rcutoff2))
1208             {
1209
1210             r10              = _mm_mul_ps(rsq10,rinv10);
1211             r10              = _mm_andnot_ps(dummy_mask,r10);
1212
1213             /* Compute parameters for interactions between i and j atoms */
1214             qq10             = _mm_mul_ps(iq1,jq0);
1215
1216             /* EWALD ELECTROSTATICS */
1217
1218             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1219             ewrt             = _mm_mul_ps(r10,ewtabscale);
1220             ewitab           = _mm_cvttps_epi32(ewrt);
1221             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
1222             gmx_mm_load_4pair_swizzle_ps(ewtab+gmx_mm_extract_epi32(ewitab,0),ewtab+gmx_mm_extract_epi32(ewitab,1),
1223                                          ewtab+gmx_mm_extract_epi32(ewitab,2),ewtab+gmx_mm_extract_epi32(ewitab,3),
1224                                          &ewtabF,&ewtabFn);
1225             felec            = _mm_add_ps(_mm_mul_ps( _mm_sub_ps(one,eweps),ewtabF),_mm_mul_ps(eweps,ewtabFn));
1226             felec            = _mm_mul_ps(_mm_mul_ps(qq10,rinv10),_mm_sub_ps(rinvsq10,felec));
1227
1228             cutoff_mask      = _mm_cmplt_ps(rsq10,rcutoff2);
1229
1230             fscal            = felec;
1231
1232             fscal            = _mm_and_ps(fscal,cutoff_mask);
1233
1234             fscal            = _mm_andnot_ps(dummy_mask,fscal);
1235
1236             /* Calculate temporary vectorial force */
1237             tx               = _mm_mul_ps(fscal,dx10);
1238             ty               = _mm_mul_ps(fscal,dy10);
1239             tz               = _mm_mul_ps(fscal,dz10);
1240
1241             /* Update vectorial force */
1242             fix1             = _mm_add_ps(fix1,tx);
1243             fiy1             = _mm_add_ps(fiy1,ty);
1244             fiz1             = _mm_add_ps(fiz1,tz);
1245
1246             fjx0             = _mm_add_ps(fjx0,tx);
1247             fjy0             = _mm_add_ps(fjy0,ty);
1248             fjz0             = _mm_add_ps(fjz0,tz);
1249
1250             }
1251
1252             /**************************
1253              * CALCULATE INTERACTIONS *
1254              **************************/
1255
1256             if (gmx_mm_any_lt(rsq20,rcutoff2))
1257             {
1258
1259             r20              = _mm_mul_ps(rsq20,rinv20);
1260             r20              = _mm_andnot_ps(dummy_mask,r20);
1261
1262             /* Compute parameters for interactions between i and j atoms */
1263             qq20             = _mm_mul_ps(iq2,jq0);
1264
1265             /* EWALD ELECTROSTATICS */
1266
1267             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1268             ewrt             = _mm_mul_ps(r20,ewtabscale);
1269             ewitab           = _mm_cvttps_epi32(ewrt);
1270             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
1271             gmx_mm_load_4pair_swizzle_ps(ewtab+gmx_mm_extract_epi32(ewitab,0),ewtab+gmx_mm_extract_epi32(ewitab,1),
1272                                          ewtab+gmx_mm_extract_epi32(ewitab,2),ewtab+gmx_mm_extract_epi32(ewitab,3),
1273                                          &ewtabF,&ewtabFn);
1274             felec            = _mm_add_ps(_mm_mul_ps( _mm_sub_ps(one,eweps),ewtabF),_mm_mul_ps(eweps,ewtabFn));
1275             felec            = _mm_mul_ps(_mm_mul_ps(qq20,rinv20),_mm_sub_ps(rinvsq20,felec));
1276
1277             cutoff_mask      = _mm_cmplt_ps(rsq20,rcutoff2);
1278
1279             fscal            = felec;
1280
1281             fscal            = _mm_and_ps(fscal,cutoff_mask);
1282
1283             fscal            = _mm_andnot_ps(dummy_mask,fscal);
1284
1285             /* Calculate temporary vectorial force */
1286             tx               = _mm_mul_ps(fscal,dx20);
1287             ty               = _mm_mul_ps(fscal,dy20);
1288             tz               = _mm_mul_ps(fscal,dz20);
1289
1290             /* Update vectorial force */
1291             fix2             = _mm_add_ps(fix2,tx);
1292             fiy2             = _mm_add_ps(fiy2,ty);
1293             fiz2             = _mm_add_ps(fiz2,tz);
1294
1295             fjx0             = _mm_add_ps(fjx0,tx);
1296             fjy0             = _mm_add_ps(fjy0,ty);
1297             fjz0             = _mm_add_ps(fjz0,tz);
1298
1299             }
1300
1301             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
1302             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
1303             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
1304             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
1305
1306             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,fjx0,fjy0,fjz0);
1307
1308             /* Inner loop uses 127 flops */
1309         }
1310
1311         /* End of innermost loop */
1312
1313         gmx_mm_update_iforce_3atom_swizzle_ps(fix0,fiy0,fiz0,fix1,fiy1,fiz1,fix2,fiy2,fiz2,
1314                                               f+i_coord_offset,fshift+i_shift_offset);
1315
1316         /* Increment number of inner iterations */
1317         inneriter                  += j_index_end - j_index_start;
1318
1319         /* Outer loop uses 18 flops */
1320     }
1321
1322     /* Increment number of outer iterations */
1323     outeriter        += nri;
1324
1325     /* Update outer/inner flops */
1326
1327     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W3_F,outeriter*18 + inneriter*127);
1328 }