src/gromacs/gmxlib/nonbonded/nb_kernel_sse4_1_single/nb_kernel_ElecNone_VdwLJEwSh_GeomP1P1_sse4_1_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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  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
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  34  */
  35 /*
  36  * Note: this file was generated by the GROMACS sse4_1_single kernel generator.
  37  */
  38 #include "gmxpre.h"
  39
  40 #include "config.h"
  41
  42 #include <math.h>
  43
  44 #include "../nb_kernel.h"
  45 #include "gromacs/legacyheaders/types/simple.h"
  46 #include "gromacs/math/vec.h"
  47 #include "gromacs/legacyheaders/nrnb.h"
  48
  49 #include "gromacs/simd/math_x86_sse4_1_single.h"
  50 #include "kernelutil_x86_sse4_1_single.h"
  51
  52 /*
  53  * Gromacs nonbonded kernel:   nb_kernel_ElecNone_VdwLJEwSh_GeomP1P1_VF_sse4_1_single
  54  * Electrostatics interaction: None
  55  * VdW interaction:            LJEwald
  56  * Geometry:                   Particle-Particle
  57  * Calculate force/pot:        PotentialAndForce
  58  */
  59 void
  60 nb_kernel_ElecNone_VdwLJEwSh_GeomP1P1_VF_sse4_1_single
  61                     (t_nblist                    * gmx_restrict       nlist,
  62                      rvec                        * gmx_restrict          xx,
  63                      rvec                        * gmx_restrict          ff,
  64                      t_forcerec                  * gmx_restrict          fr,
  65                      t_mdatoms                   * gmx_restrict     mdatoms,
  66                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
  67                      t_nrnb                      * gmx_restrict        nrnb)
  68 {
  69     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or
  70      * just 0 for non-waters.
  71      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
  72      * jnr indices corresponding to data put in the four positions in the SIMD register.
  73      */
  74     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
  75     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
  76     int              jnrA,jnrB,jnrC,jnrD;
  77     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
  78     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
  79     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  80     real             rcutoff_scalar;
  81     real             *shiftvec,*fshift,*x,*f;
  82     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
  83     real             scratch[4*DIM];
  84     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
  85     int              vdwioffset0;
  86     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  87     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
  88     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  89     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
  90     int              nvdwtype;
  91     __m128           rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
  92     int              *vdwtype;
  93     real             *vdwparam;
  94     __m128           one_sixth   = _mm_set1_ps(1.0/6.0);
  95     __m128           one_twelfth = _mm_set1_ps(1.0/12.0);
  96     __m128           c6grid_00;
  97     __m128           ewclj,ewclj2,ewclj6,ewcljrsq,poly,exponent,f6A,f6B,sh_lj_ewald;
  98     real             *vdwgridparam;
  99     __m128           one_half  = _mm_set1_ps(0.5);
 100     __m128           minus_one = _mm_set1_ps(-1.0);
 101     __m128           dummy_mask,cutoff_mask;
 102     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
 103     __m128           one     = _mm_set1_ps(1.0);
 104     __m128           two     = _mm_set1_ps(2.0);
 105     x                = xx[0];
 106     f                = ff[0];
 107
 108     nri              = nlist->nri;
 109     iinr             = nlist->iinr;
 110     jindex           = nlist->jindex;
 111     jjnr             = nlist->jjnr;
 112     shiftidx         = nlist->shift;
 113     gid              = nlist->gid;
 114     shiftvec         = fr->shift_vec[0];
 115     fshift           = fr->fshift[0];
 116     nvdwtype         = fr->ntype;
 117     vdwparam         = fr->nbfp;
 118     vdwtype          = mdatoms->typeA;
 119     vdwgridparam     = fr->ljpme_c6grid;
 120     sh_lj_ewald      = _mm_set1_ps(fr->ic->sh_lj_ewald);
 121     ewclj            = _mm_set1_ps(fr->ewaldcoeff_lj);
 122     ewclj2           = _mm_mul_ps(minus_one,_mm_mul_ps(ewclj,ewclj));
 123
 124     rcutoff_scalar   = fr->rvdw;
 125     rcutoff          = _mm_set1_ps(rcutoff_scalar);
 126     rcutoff2         = _mm_mul_ps(rcutoff,rcutoff);
 127
 128     sh_vdw_invrcut6  = _mm_set1_ps(fr->ic->sh_invrc6);
 129     rvdw             = _mm_set1_ps(fr->rvdw);
 130
 131     /* Avoid stupid compiler warnings */
 132     jnrA = jnrB = jnrC = jnrD = 0;
 133     j_coord_offsetA = 0;
 134     j_coord_offsetB = 0;
 135     j_coord_offsetC = 0;
 136     j_coord_offsetD = 0;
 137
 138     outeriter        = 0;
 139     inneriter        = 0;
 140
 141     for(iidx=0;iidx<4*DIM;iidx++)
 142     {
 143         scratch[iidx] = 0.0;
 144     }
 145
 146     /* Start outer loop over neighborlists */
 147     for(iidx=0; iidx<nri; iidx++)
 148     {
 149         /* Load shift vector for this list */
 150         i_shift_offset   = DIM*shiftidx[iidx];
 151
 152         /* Load limits for loop over neighbors */
 153         j_index_start    = jindex[iidx];
 154         j_index_end      = jindex[iidx+1];
 155
 156         /* Get outer coordinate index */
 157         inr              = iinr[iidx];
 158         i_coord_offset   = DIM*inr;
 159
 160         /* Load i particle coords and add shift vector */
 161         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 162
 163         fix0             = _mm_setzero_ps();
 164         fiy0             = _mm_setzero_ps();
 165         fiz0             = _mm_setzero_ps();
 166
 167         /* Load parameters for i particles */
 168         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 169
 170         /* Reset potential sums */
 171         vvdwsum          = _mm_setzero_ps();
 172
 173         /* Start inner kernel loop */
 174         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
 175         {
 176
 177             /* Get j neighbor index, and coordinate index */
 178             jnrA             = jjnr[jidx];
 179             jnrB             = jjnr[jidx+1];
 180             jnrC             = jjnr[jidx+2];
 181             jnrD             = jjnr[jidx+3];
 182             j_coord_offsetA  = DIM*jnrA;
 183             j_coord_offsetB  = DIM*jnrB;
 184             j_coord_offsetC  = DIM*jnrC;
 185             j_coord_offsetD  = DIM*jnrD;
 186
 187             /* load j atom coordinates */
 188             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 189                                               x+j_coord_offsetC,x+j_coord_offsetD,
 190                                               &jx0,&jy0,&jz0);
 191
 192             /* Calculate displacement vector */
 193             dx00             = _mm_sub_ps(ix0,jx0);
 194             dy00             = _mm_sub_ps(iy0,jy0);
 195             dz00             = _mm_sub_ps(iz0,jz0);
 196
 197             /* Calculate squared distance and things based on it */
 198             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 199
 200             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 201
 202             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
 203
 204             /* Load parameters for j particles */
 205             vdwjidx0A        = 2*vdwtype[jnrA+0];
 206             vdwjidx0B        = 2*vdwtype[jnrB+0];
 207             vdwjidx0C        = 2*vdwtype[jnrC+0];
 208             vdwjidx0D        = 2*vdwtype[jnrD+0];
 209
 210             /**************************
 211              * CALCULATE INTERACTIONS *
 212              **************************/
 213
 214             if (gmx_mm_any_lt(rsq00,rcutoff2))
 215             {
 216
 217             r00              = _mm_mul_ps(rsq00,rinv00);
 218
 219             /* Compute parameters for interactions between i and j atoms */
 220             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
 221                                          vdwparam+vdwioffset0+vdwjidx0B,
 222                                          vdwparam+vdwioffset0+vdwjidx0C,
 223                                          vdwparam+vdwioffset0+vdwjidx0D,
 224                                          &c6_00,&c12_00);
 225
 226             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
 227                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
 228                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
 229                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
 230
 231             /* Analytical LJ-PME */
 232             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
 233             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
 234             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
 235             exponent         = gmx_simd_exp_r(ewcljrsq);
 236             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
 237             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
 238             /* vvdw6 = [C6 - C6grid * (1-poly)]/r6 */
 239             vvdw6            = _mm_mul_ps(_mm_sub_ps(c6_00,_mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly))),rinvsix);
 240             vvdw12           = _mm_mul_ps(c12_00,_mm_mul_ps(rinvsix,rinvsix));
 241             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),
 242                                _mm_mul_ps( _mm_sub_ps(vvdw6,_mm_add_ps(_mm_mul_ps(c6_00,sh_vdw_invrcut6),_mm_mul_ps(c6grid_00,sh_lj_ewald))),one_sixth));
 243             /* fvdw = vvdw12/r - (vvdw6/r + (C6grid * exponent * beta^6)/r) */
 244             fvdw             = _mm_mul_ps(_mm_sub_ps(vvdw12,_mm_sub_ps(vvdw6,_mm_mul_ps(_mm_mul_ps(c6grid_00,one_sixth),_mm_mul_ps(exponent,ewclj6)))),rinvsq00);
 245
 246             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
 247
 248             /* Update potential sum for this i atom from the interaction with this j atom. */
 249             vvdw             = _mm_and_ps(vvdw,cutoff_mask);
 250             vvdwsum          = _mm_add_ps(vvdwsum,vvdw);
 251
 252             fscal            = fvdw;
 253
 254             fscal            = _mm_and_ps(fscal,cutoff_mask);
 255
 256             /* Calculate temporary vectorial force */
 257             tx               = _mm_mul_ps(fscal,dx00);
 258             ty               = _mm_mul_ps(fscal,dy00);
 259             tz               = _mm_mul_ps(fscal,dz00);
 260
 261             /* Update vectorial force */
 262             fix0             = _mm_add_ps(fix0,tx);
 263             fiy0             = _mm_add_ps(fiy0,ty);
 264             fiz0             = _mm_add_ps(fiz0,tz);
 265
 266             fjptrA             = f+j_coord_offsetA;
 267             fjptrB             = f+j_coord_offsetB;
 268             fjptrC             = f+j_coord_offsetC;
 269             fjptrD             = f+j_coord_offsetD;
 270             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 271
 272             }
 273
 274             /* Inner loop uses 62 flops */
 275         }
 276
 277         if(jidx<j_index_end)
 278         {
 279
 280             /* Get j neighbor index, and coordinate index */
 281             jnrlistA         = jjnr[jidx];
 282             jnrlistB         = jjnr[jidx+1];
 283             jnrlistC         = jjnr[jidx+2];
 284             jnrlistD         = jjnr[jidx+3];
 285             /* Sign of each element will be negative for non-real atoms.
 286              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
 287              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
 288              */
 289             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
 290             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
 291             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
 292             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
 293             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
 294             j_coord_offsetA  = DIM*jnrA;
 295             j_coord_offsetB  = DIM*jnrB;
 296             j_coord_offsetC  = DIM*jnrC;
 297             j_coord_offsetD  = DIM*jnrD;
 298
 299             /* load j atom coordinates */
 300             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 301                                               x+j_coord_offsetC,x+j_coord_offsetD,
 302                                               &jx0,&jy0,&jz0);
 303
 304             /* Calculate displacement vector */
 305             dx00             = _mm_sub_ps(ix0,jx0);
 306             dy00             = _mm_sub_ps(iy0,jy0);
 307             dz00             = _mm_sub_ps(iz0,jz0);
 308
 309             /* Calculate squared distance and things based on it */
 310             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 311
 312             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 313
 314             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
 315
 316             /* Load parameters for j particles */
 317             vdwjidx0A        = 2*vdwtype[jnrA+0];
 318             vdwjidx0B        = 2*vdwtype[jnrB+0];
 319             vdwjidx0C        = 2*vdwtype[jnrC+0];
 320             vdwjidx0D        = 2*vdwtype[jnrD+0];
 321
 322             /**************************
 323              * CALCULATE INTERACTIONS *
 324              **************************/
 325
 326             if (gmx_mm_any_lt(rsq00,rcutoff2))
 327             {
 328
 329             r00              = _mm_mul_ps(rsq00,rinv00);
 330             r00              = _mm_andnot_ps(dummy_mask,r00);
 331
 332             /* Compute parameters for interactions between i and j atoms */
 333             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
 334                                          vdwparam+vdwioffset0+vdwjidx0B,
 335                                          vdwparam+vdwioffset0+vdwjidx0C,
 336                                          vdwparam+vdwioffset0+vdwjidx0D,
 337                                          &c6_00,&c12_00);
 338
 339             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
 340                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
 341                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
 342                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
 343
 344             /* Analytical LJ-PME */
 345             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
 346             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
 347             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
 348             exponent         = gmx_simd_exp_r(ewcljrsq);
 349             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
 350             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
 351             /* vvdw6 = [C6 - C6grid * (1-poly)]/r6 */
 352             vvdw6            = _mm_mul_ps(_mm_sub_ps(c6_00,_mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly))),rinvsix);
 353             vvdw12           = _mm_mul_ps(c12_00,_mm_mul_ps(rinvsix,rinvsix));
 354             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),
 355                                _mm_mul_ps( _mm_sub_ps(vvdw6,_mm_add_ps(_mm_mul_ps(c6_00,sh_vdw_invrcut6),_mm_mul_ps(c6grid_00,sh_lj_ewald))),one_sixth));
 356             /* fvdw = vvdw12/r - (vvdw6/r + (C6grid * exponent * beta^6)/r) */
 357             fvdw             = _mm_mul_ps(_mm_sub_ps(vvdw12,_mm_sub_ps(vvdw6,_mm_mul_ps(_mm_mul_ps(c6grid_00,one_sixth),_mm_mul_ps(exponent,ewclj6)))),rinvsq00);
 358
 359             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
 360
 361             /* Update potential sum for this i atom from the interaction with this j atom. */
 362             vvdw             = _mm_and_ps(vvdw,cutoff_mask);
 363             vvdw             = _mm_andnot_ps(dummy_mask,vvdw);
 364             vvdwsum          = _mm_add_ps(vvdwsum,vvdw);
 365
 366             fscal            = fvdw;
 367
 368             fscal            = _mm_and_ps(fscal,cutoff_mask);
 369
 370             fscal            = _mm_andnot_ps(dummy_mask,fscal);
 371
 372             /* Calculate temporary vectorial force */
 373             tx               = _mm_mul_ps(fscal,dx00);
 374             ty               = _mm_mul_ps(fscal,dy00);
 375             tz               = _mm_mul_ps(fscal,dz00);
 376
 377             /* Update vectorial force */
 378             fix0             = _mm_add_ps(fix0,tx);
 379             fiy0             = _mm_add_ps(fiy0,ty);
 380             fiz0             = _mm_add_ps(fiz0,tz);
 381
 382             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
 383             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
 384             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
 385             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
 386             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 387
 388             }
 389
 390             /* Inner loop uses 63 flops */
 391         }
 392
 393         /* End of innermost loop */
 394
 395         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
 396                                               f+i_coord_offset,fshift+i_shift_offset);
 397
 398         ggid                        = gid[iidx];
 399         /* Update potential energies */
 400         gmx_mm_update_1pot_ps(vvdwsum,kernel_data->energygrp_vdw+ggid);
 401
 402         /* Increment number of inner iterations */
 403         inneriter                  += j_index_end - j_index_start;
 404
 405         /* Outer loop uses 7 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_VDW_VF,outeriter*7 + inneriter*63);
 414 }
 415 /*
 416  * Gromacs nonbonded kernel:   nb_kernel_ElecNone_VdwLJEwSh_GeomP1P1_F_sse4_1_single
 417  * Electrostatics interaction: None
 418  * VdW interaction:            LJEwald
 419  * Geometry:                   Particle-Particle
 420  * Calculate force/pot:        Force
 421  */
 422 void
 423 nb_kernel_ElecNone_VdwLJEwSh_GeomP1P1_F_sse4_1_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     int              nvdwtype;
 454     __m128           rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
 455     int              *vdwtype;
 456     real             *vdwparam;
 457     __m128           one_sixth   = _mm_set1_ps(1.0/6.0);
 458     __m128           one_twelfth = _mm_set1_ps(1.0/12.0);
 459     __m128           c6grid_00;
 460     __m128           ewclj,ewclj2,ewclj6,ewcljrsq,poly,exponent,f6A,f6B,sh_lj_ewald;
 461     real             *vdwgridparam;
 462     __m128           one_half  = _mm_set1_ps(0.5);
 463     __m128           minus_one = _mm_set1_ps(-1.0);
 464     __m128           dummy_mask,cutoff_mask;
 465     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
 466     __m128           one     = _mm_set1_ps(1.0);
 467     __m128           two     = _mm_set1_ps(2.0);
 468     x                = xx[0];
 469     f                = ff[0];
 470
 471     nri              = nlist->nri;
 472     iinr             = nlist->iinr;
 473     jindex           = nlist->jindex;
 474     jjnr             = nlist->jjnr;
 475     shiftidx         = nlist->shift;
 476     gid              = nlist->gid;
 477     shiftvec         = fr->shift_vec[0];
 478     fshift           = fr->fshift[0];
 479     nvdwtype         = fr->ntype;
 480     vdwparam         = fr->nbfp;
 481     vdwtype          = mdatoms->typeA;
 482     vdwgridparam     = fr->ljpme_c6grid;
 483     sh_lj_ewald      = _mm_set1_ps(fr->ic->sh_lj_ewald);
 484     ewclj            = _mm_set1_ps(fr->ewaldcoeff_lj);
 485     ewclj2           = _mm_mul_ps(minus_one,_mm_mul_ps(ewclj,ewclj));
 486
 487     rcutoff_scalar   = fr->rvdw;
 488     rcutoff          = _mm_set1_ps(rcutoff_scalar);
 489     rcutoff2         = _mm_mul_ps(rcutoff,rcutoff);
 490
 491     sh_vdw_invrcut6  = _mm_set1_ps(fr->ic->sh_invrc6);
 492     rvdw             = _mm_set1_ps(fr->rvdw);
 493
 494     /* Avoid stupid compiler warnings */
 495     jnrA = jnrB = jnrC = jnrD = 0;
 496     j_coord_offsetA = 0;
 497     j_coord_offsetB = 0;
 498     j_coord_offsetC = 0;
 499     j_coord_offsetD = 0;
 500
 501     outeriter        = 0;
 502     inneriter        = 0;
 503
 504     for(iidx=0;iidx<4*DIM;iidx++)
 505     {
 506         scratch[iidx] = 0.0;
 507     }
 508
 509     /* Start outer loop over neighborlists */
 510     for(iidx=0; iidx<nri; iidx++)
 511     {
 512         /* Load shift vector for this list */
 513         i_shift_offset   = DIM*shiftidx[iidx];
 514
 515         /* Load limits for loop over neighbors */
 516         j_index_start    = jindex[iidx];
 517         j_index_end      = jindex[iidx+1];
 518
 519         /* Get outer coordinate index */
 520         inr              = iinr[iidx];
 521         i_coord_offset   = DIM*inr;
 522
 523         /* Load i particle coords and add shift vector */
 524         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
 525
 526         fix0             = _mm_setzero_ps();
 527         fiy0             = _mm_setzero_ps();
 528         fiz0             = _mm_setzero_ps();
 529
 530         /* Load parameters for i particles */
 531         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
 532
 533         /* Start inner kernel loop */
 534         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
 535         {
 536
 537             /* Get j neighbor index, and coordinate index */
 538             jnrA             = jjnr[jidx];
 539             jnrB             = jjnr[jidx+1];
 540             jnrC             = jjnr[jidx+2];
 541             jnrD             = jjnr[jidx+3];
 542             j_coord_offsetA  = DIM*jnrA;
 543             j_coord_offsetB  = DIM*jnrB;
 544             j_coord_offsetC  = DIM*jnrC;
 545             j_coord_offsetD  = DIM*jnrD;
 546
 547             /* load j atom coordinates */
 548             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 549                                               x+j_coord_offsetC,x+j_coord_offsetD,
 550                                               &jx0,&jy0,&jz0);
 551
 552             /* Calculate displacement vector */
 553             dx00             = _mm_sub_ps(ix0,jx0);
 554             dy00             = _mm_sub_ps(iy0,jy0);
 555             dz00             = _mm_sub_ps(iz0,jz0);
 556
 557             /* Calculate squared distance and things based on it */
 558             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 559
 560             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 561
 562             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
 563
 564             /* Load parameters for j particles */
 565             vdwjidx0A        = 2*vdwtype[jnrA+0];
 566             vdwjidx0B        = 2*vdwtype[jnrB+0];
 567             vdwjidx0C        = 2*vdwtype[jnrC+0];
 568             vdwjidx0D        = 2*vdwtype[jnrD+0];
 569
 570             /**************************
 571              * CALCULATE INTERACTIONS *
 572              **************************/
 573
 574             if (gmx_mm_any_lt(rsq00,rcutoff2))
 575             {
 576
 577             r00              = _mm_mul_ps(rsq00,rinv00);
 578
 579             /* Compute parameters for interactions between i and j atoms */
 580             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
 581                                          vdwparam+vdwioffset0+vdwjidx0B,
 582                                          vdwparam+vdwioffset0+vdwjidx0C,
 583                                          vdwparam+vdwioffset0+vdwjidx0D,
 584                                          &c6_00,&c12_00);
 585
 586             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
 587                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
 588                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
 589                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
 590
 591             /* Analytical LJ-PME */
 592             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
 593             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
 594             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
 595             exponent         = gmx_simd_exp_r(ewcljrsq);
 596             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
 597             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
 598             /* f6A = 6 * C6grid * (1 - poly) */
 599             f6A              = _mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly));
 600             /* f6B = C6grid * exponent * beta^6 */
 601             f6B              = _mm_mul_ps(_mm_mul_ps(c6grid_00,one_sixth),_mm_mul_ps(exponent,ewclj6));
 602             /* fvdw = 12*C12/r13 - ((6*C6 - f6A)/r6 + f6B)/r */
 603             fvdw              = _mm_mul_ps(_mm_add_ps(_mm_mul_ps(_mm_sub_ps(_mm_mul_ps(c12_00,rinvsix),_mm_sub_ps(c6_00,f6A)),rinvsix),f6B),rinvsq00);
 604
 605             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
 606
 607             fscal            = fvdw;
 608
 609             fscal            = _mm_and_ps(fscal,cutoff_mask);
 610
 611             /* Calculate temporary vectorial force */
 612             tx               = _mm_mul_ps(fscal,dx00);
 613             ty               = _mm_mul_ps(fscal,dy00);
 614             tz               = _mm_mul_ps(fscal,dz00);
 615
 616             /* Update vectorial force */
 617             fix0             = _mm_add_ps(fix0,tx);
 618             fiy0             = _mm_add_ps(fiy0,ty);
 619             fiz0             = _mm_add_ps(fiz0,tz);
 620
 621             fjptrA             = f+j_coord_offsetA;
 622             fjptrB             = f+j_coord_offsetB;
 623             fjptrC             = f+j_coord_offsetC;
 624             fjptrD             = f+j_coord_offsetD;
 625             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 626
 627             }
 628
 629             /* Inner loop uses 49 flops */
 630         }
 631
 632         if(jidx<j_index_end)
 633         {
 634
 635             /* Get j neighbor index, and coordinate index */
 636             jnrlistA         = jjnr[jidx];
 637             jnrlistB         = jjnr[jidx+1];
 638             jnrlistC         = jjnr[jidx+2];
 639             jnrlistD         = jjnr[jidx+3];
 640             /* Sign of each element will be negative for non-real atoms.
 641              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
 642              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
 643              */
 644             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
 645             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
 646             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
 647             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
 648             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
 649             j_coord_offsetA  = DIM*jnrA;
 650             j_coord_offsetB  = DIM*jnrB;
 651             j_coord_offsetC  = DIM*jnrC;
 652             j_coord_offsetD  = DIM*jnrD;
 653
 654             /* load j atom coordinates */
 655             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
 656                                               x+j_coord_offsetC,x+j_coord_offsetD,
 657                                               &jx0,&jy0,&jz0);
 658
 659             /* Calculate displacement vector */
 660             dx00             = _mm_sub_ps(ix0,jx0);
 661             dy00             = _mm_sub_ps(iy0,jy0);
 662             dz00             = _mm_sub_ps(iz0,jz0);
 663
 664             /* Calculate squared distance and things based on it */
 665             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
 666
 667             rinv00           = gmx_mm_invsqrt_ps(rsq00);
 668
 669             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
 670
 671             /* Load parameters for j particles */
 672             vdwjidx0A        = 2*vdwtype[jnrA+0];
 673             vdwjidx0B        = 2*vdwtype[jnrB+0];
 674             vdwjidx0C        = 2*vdwtype[jnrC+0];
 675             vdwjidx0D        = 2*vdwtype[jnrD+0];
 676
 677             /**************************
 678              * CALCULATE INTERACTIONS *
 679              **************************/
 680
 681             if (gmx_mm_any_lt(rsq00,rcutoff2))
 682             {
 683
 684             r00              = _mm_mul_ps(rsq00,rinv00);
 685             r00              = _mm_andnot_ps(dummy_mask,r00);
 686
 687             /* Compute parameters for interactions between i and j atoms */
 688             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
 689                                          vdwparam+vdwioffset0+vdwjidx0B,
 690                                          vdwparam+vdwioffset0+vdwjidx0C,
 691                                          vdwparam+vdwioffset0+vdwjidx0D,
 692                                          &c6_00,&c12_00);
 693
 694             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
 695                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
 696                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
 697                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
 698
 699             /* Analytical LJ-PME */
 700             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
 701             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
 702             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
 703             exponent         = gmx_simd_exp_r(ewcljrsq);
 704             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
 705             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
 706             /* f6A = 6 * C6grid * (1 - poly) */
 707             f6A              = _mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly));
 708             /* f6B = C6grid * exponent * beta^6 */
 709             f6B              = _mm_mul_ps(_mm_mul_ps(c6grid_00,one_sixth),_mm_mul_ps(exponent,ewclj6));
 710             /* fvdw = 12*C12/r13 - ((6*C6 - f6A)/r6 + f6B)/r */
 711             fvdw              = _mm_mul_ps(_mm_add_ps(_mm_mul_ps(_mm_sub_ps(_mm_mul_ps(c12_00,rinvsix),_mm_sub_ps(c6_00,f6A)),rinvsix),f6B),rinvsq00);
 712
 713             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
 714
 715             fscal            = fvdw;
 716
 717             fscal            = _mm_and_ps(fscal,cutoff_mask);
 718
 719             fscal            = _mm_andnot_ps(dummy_mask,fscal);
 720
 721             /* Calculate temporary vectorial force */
 722             tx               = _mm_mul_ps(fscal,dx00);
 723             ty               = _mm_mul_ps(fscal,dy00);
 724             tz               = _mm_mul_ps(fscal,dz00);
 725
 726             /* Update vectorial force */
 727             fix0             = _mm_add_ps(fix0,tx);
 728             fiy0             = _mm_add_ps(fiy0,ty);
 729             fiz0             = _mm_add_ps(fiz0,tz);
 730
 731             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
 732             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
 733             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
 734             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
 735             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
 736
 737             }
 738
 739             /* Inner loop uses 50 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         /* Increment number of inner iterations */
 748         inneriter                  += j_index_end - j_index_start;
 749
 750         /* Outer loop uses 6 flops */
 751     }
 752
 753     /* Increment number of outer iterations */
 754     outeriter        += nri;
 755
 756     /* Update outer/inner flops */
 757
 758     inc_nrnb(nrnb,eNR_NBKERNEL_VDW_F,outeriter*6 + inneriter*50);
 759 }