Compile nonbonded kernels as C++
[alexxy/gromacs.git] / src / gromacs / gmxlib / nonbonded / nb_kernel_sse2_single / nb_kernel_ElecNone_VdwLJ_GeomP1P1_sse2_single.cpp
1 /*
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35 /*
36  * Note: this file was generated by the GROMACS sse2_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/gmxlib/nrnb.h"
46
47 #include "kernelutil_x86_sse2_single.h"
48
49 /*
50  * Gromacs nonbonded kernel:   nb_kernel_ElecNone_VdwLJ_GeomP1P1_VF_sse2_single
51  * Electrostatics interaction: None
52  * VdW interaction:            LennardJones
53  * Geometry:                   Particle-Particle
54  * Calculate force/pot:        PotentialAndForce
55  */
56 void
57 nb_kernel_ElecNone_VdwLJ_GeomP1P1_VF_sse2_single
58                     (t_nblist                    * gmx_restrict       nlist,
59                      rvec                        * gmx_restrict          xx,
60                      rvec                        * gmx_restrict          ff,
61                      struct t_forcerec           * gmx_restrict          fr,
62                      t_mdatoms                   * gmx_restrict     mdatoms,
63                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
64                      t_nrnb                      * gmx_restrict        nrnb)
65 {
66     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or 
67      * just 0 for non-waters.
68      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
69      * jnr indices corresponding to data put in the four positions in the SIMD register.
70      */
71     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
72     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
73     int              jnrA,jnrB,jnrC,jnrD;
74     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
75     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
76     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
77     real             rcutoff_scalar;
78     real             *shiftvec,*fshift,*x,*f;
79     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
80     real             scratch[4*DIM];
81     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
82     int              vdwioffset0;
83     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
84     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
85     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
86     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
87     int              nvdwtype;
88     __m128           rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
89     int              *vdwtype;
90     real             *vdwparam;
91     __m128           one_sixth   = _mm_set1_ps(1.0/6.0);
92     __m128           one_twelfth = _mm_set1_ps(1.0/12.0);
93     __m128           dummy_mask,cutoff_mask;
94     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
95     __m128           one     = _mm_set1_ps(1.0);
96     __m128           two     = _mm_set1_ps(2.0);
97     x                = xx[0];
98     f                = ff[0];
99
100     nri              = nlist->nri;
101     iinr             = nlist->iinr;
102     jindex           = nlist->jindex;
103     jjnr             = nlist->jjnr;
104     shiftidx         = nlist->shift;
105     gid              = nlist->gid;
106     shiftvec         = fr->shift_vec[0];
107     fshift           = fr->fshift[0];
108     nvdwtype         = fr->ntype;
109     vdwparam         = fr->nbfp;
110     vdwtype          = mdatoms->typeA;
111
112     /* Avoid stupid compiler warnings */
113     jnrA = jnrB = jnrC = jnrD = 0;
114     j_coord_offsetA = 0;
115     j_coord_offsetB = 0;
116     j_coord_offsetC = 0;
117     j_coord_offsetD = 0;
118
119     outeriter        = 0;
120     inneriter        = 0;
121
122     for(iidx=0;iidx<4*DIM;iidx++)
123     {
124         scratch[iidx] = 0.0;
125     }  
126
127     /* Start outer loop over neighborlists */
128     for(iidx=0; iidx<nri; iidx++)
129     {
130         /* Load shift vector for this list */
131         i_shift_offset   = DIM*shiftidx[iidx];
132
133         /* Load limits for loop over neighbors */
134         j_index_start    = jindex[iidx];
135         j_index_end      = jindex[iidx+1];
136
137         /* Get outer coordinate index */
138         inr              = iinr[iidx];
139         i_coord_offset   = DIM*inr;
140
141         /* Load i particle coords and add shift vector */
142         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
143         
144         fix0             = _mm_setzero_ps();
145         fiy0             = _mm_setzero_ps();
146         fiz0             = _mm_setzero_ps();
147
148         /* Load parameters for i particles */
149         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
150
151         /* Reset potential sums */
152         vvdwsum          = _mm_setzero_ps();
153
154         /* Start inner kernel loop */
155         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
156         {
157
158             /* Get j neighbor index, and coordinate index */
159             jnrA             = jjnr[jidx];
160             jnrB             = jjnr[jidx+1];
161             jnrC             = jjnr[jidx+2];
162             jnrD             = jjnr[jidx+3];
163             j_coord_offsetA  = DIM*jnrA;
164             j_coord_offsetB  = DIM*jnrB;
165             j_coord_offsetC  = DIM*jnrC;
166             j_coord_offsetD  = DIM*jnrD;
167
168             /* load j atom coordinates */
169             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
170                                               x+j_coord_offsetC,x+j_coord_offsetD,
171                                               &jx0,&jy0,&jz0);
172
173             /* Calculate displacement vector */
174             dx00             = _mm_sub_ps(ix0,jx0);
175             dy00             = _mm_sub_ps(iy0,jy0);
176             dz00             = _mm_sub_ps(iz0,jz0);
177
178             /* Calculate squared distance and things based on it */
179             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
180
181             rinvsq00         = sse2_inv_f(rsq00);
182
183             /* Load parameters for j particles */
184             vdwjidx0A        = 2*vdwtype[jnrA+0];
185             vdwjidx0B        = 2*vdwtype[jnrB+0];
186             vdwjidx0C        = 2*vdwtype[jnrC+0];
187             vdwjidx0D        = 2*vdwtype[jnrD+0];
188
189             /**************************
190              * CALCULATE INTERACTIONS *
191              **************************/
192
193             /* Compute parameters for interactions between i and j atoms */
194             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
195                                          vdwparam+vdwioffset0+vdwjidx0B,
196                                          vdwparam+vdwioffset0+vdwjidx0C,
197                                          vdwparam+vdwioffset0+vdwjidx0D,
198                                          &c6_00,&c12_00);
199
200             /* LENNARD-JONES DISPERSION/REPULSION */
201
202             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
203             vvdw6            = _mm_mul_ps(c6_00,rinvsix);
204             vvdw12           = _mm_mul_ps(c12_00,_mm_mul_ps(rinvsix,rinvsix));
205             vvdw             = _mm_sub_ps( _mm_mul_ps(vvdw12,one_twelfth) , _mm_mul_ps(vvdw6,one_sixth) );
206             fvdw             = _mm_mul_ps(_mm_sub_ps(vvdw12,vvdw6),rinvsq00);
207
208             /* Update potential sum for this i atom from the interaction with this j atom. */
209             vvdwsum          = _mm_add_ps(vvdwsum,vvdw);
210
211             fscal            = fvdw;
212
213             /* Calculate temporary vectorial force */
214             tx               = _mm_mul_ps(fscal,dx00);
215             ty               = _mm_mul_ps(fscal,dy00);
216             tz               = _mm_mul_ps(fscal,dz00);
217
218             /* Update vectorial force */
219             fix0             = _mm_add_ps(fix0,tx);
220             fiy0             = _mm_add_ps(fiy0,ty);
221             fiz0             = _mm_add_ps(fiz0,tz);
222
223             fjptrA             = f+j_coord_offsetA;
224             fjptrB             = f+j_coord_offsetB;
225             fjptrC             = f+j_coord_offsetC;
226             fjptrD             = f+j_coord_offsetD;
227             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
228             
229             /* Inner loop uses 32 flops */
230         }
231
232         if(jidx<j_index_end)
233         {
234
235             /* Get j neighbor index, and coordinate index */
236             jnrlistA         = jjnr[jidx];
237             jnrlistB         = jjnr[jidx+1];
238             jnrlistC         = jjnr[jidx+2];
239             jnrlistD         = jjnr[jidx+3];
240             /* Sign of each element will be negative for non-real atoms.
241              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
242              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
243              */
244             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
245             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
246             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
247             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
248             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
249             j_coord_offsetA  = DIM*jnrA;
250             j_coord_offsetB  = DIM*jnrB;
251             j_coord_offsetC  = DIM*jnrC;
252             j_coord_offsetD  = DIM*jnrD;
253
254             /* load j atom coordinates */
255             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
256                                               x+j_coord_offsetC,x+j_coord_offsetD,
257                                               &jx0,&jy0,&jz0);
258
259             /* Calculate displacement vector */
260             dx00             = _mm_sub_ps(ix0,jx0);
261             dy00             = _mm_sub_ps(iy0,jy0);
262             dz00             = _mm_sub_ps(iz0,jz0);
263
264             /* Calculate squared distance and things based on it */
265             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
266
267             rinvsq00         = sse2_inv_f(rsq00);
268
269             /* Load parameters for j particles */
270             vdwjidx0A        = 2*vdwtype[jnrA+0];
271             vdwjidx0B        = 2*vdwtype[jnrB+0];
272             vdwjidx0C        = 2*vdwtype[jnrC+0];
273             vdwjidx0D        = 2*vdwtype[jnrD+0];
274
275             /**************************
276              * CALCULATE INTERACTIONS *
277              **************************/
278
279             /* Compute parameters for interactions between i and j atoms */
280             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
281                                          vdwparam+vdwioffset0+vdwjidx0B,
282                                          vdwparam+vdwioffset0+vdwjidx0C,
283                                          vdwparam+vdwioffset0+vdwjidx0D,
284                                          &c6_00,&c12_00);
285
286             /* LENNARD-JONES DISPERSION/REPULSION */
287
288             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
289             vvdw6            = _mm_mul_ps(c6_00,rinvsix);
290             vvdw12           = _mm_mul_ps(c12_00,_mm_mul_ps(rinvsix,rinvsix));
291             vvdw             = _mm_sub_ps( _mm_mul_ps(vvdw12,one_twelfth) , _mm_mul_ps(vvdw6,one_sixth) );
292             fvdw             = _mm_mul_ps(_mm_sub_ps(vvdw12,vvdw6),rinvsq00);
293
294             /* Update potential sum for this i atom from the interaction with this j atom. */
295             vvdw             = _mm_andnot_ps(dummy_mask,vvdw);
296             vvdwsum          = _mm_add_ps(vvdwsum,vvdw);
297
298             fscal            = fvdw;
299
300             fscal            = _mm_andnot_ps(dummy_mask,fscal);
301
302             /* Calculate temporary vectorial force */
303             tx               = _mm_mul_ps(fscal,dx00);
304             ty               = _mm_mul_ps(fscal,dy00);
305             tz               = _mm_mul_ps(fscal,dz00);
306
307             /* Update vectorial force */
308             fix0             = _mm_add_ps(fix0,tx);
309             fiy0             = _mm_add_ps(fiy0,ty);
310             fiz0             = _mm_add_ps(fiz0,tz);
311
312             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
313             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
314             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
315             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
316             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
317             
318             /* Inner loop uses 32 flops */
319         }
320
321         /* End of innermost loop */
322
323         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
324                                               f+i_coord_offset,fshift+i_shift_offset);
325
326         ggid                        = gid[iidx];
327         /* Update potential energies */
328         gmx_mm_update_1pot_ps(vvdwsum,kernel_data->energygrp_vdw+ggid);
329
330         /* Increment number of inner iterations */
331         inneriter                  += j_index_end - j_index_start;
332
333         /* Outer loop uses 7 flops */
334     }
335
336     /* Increment number of outer iterations */
337     outeriter        += nri;
338
339     /* Update outer/inner flops */
340
341     inc_nrnb(nrnb,eNR_NBKERNEL_VDW_VF,outeriter*7 + inneriter*32);
342 }
343 /*
344  * Gromacs nonbonded kernel:   nb_kernel_ElecNone_VdwLJ_GeomP1P1_F_sse2_single
345  * Electrostatics interaction: None
346  * VdW interaction:            LennardJones
347  * Geometry:                   Particle-Particle
348  * Calculate force/pot:        Force
349  */
350 void
351 nb_kernel_ElecNone_VdwLJ_GeomP1P1_F_sse2_single
352                     (t_nblist                    * gmx_restrict       nlist,
353                      rvec                        * gmx_restrict          xx,
354                      rvec                        * gmx_restrict          ff,
355                      struct t_forcerec           * gmx_restrict          fr,
356                      t_mdatoms                   * gmx_restrict     mdatoms,
357                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
358                      t_nrnb                      * gmx_restrict        nrnb)
359 {
360     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or 
361      * just 0 for non-waters.
362      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
363      * jnr indices corresponding to data put in the four positions in the SIMD register.
364      */
365     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
366     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
367     int              jnrA,jnrB,jnrC,jnrD;
368     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
369     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
370     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
371     real             rcutoff_scalar;
372     real             *shiftvec,*fshift,*x,*f;
373     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
374     real             scratch[4*DIM];
375     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
376     int              vdwioffset0;
377     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
378     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
379     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
380     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
381     int              nvdwtype;
382     __m128           rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
383     int              *vdwtype;
384     real             *vdwparam;
385     __m128           one_sixth   = _mm_set1_ps(1.0/6.0);
386     __m128           one_twelfth = _mm_set1_ps(1.0/12.0);
387     __m128           dummy_mask,cutoff_mask;
388     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
389     __m128           one     = _mm_set1_ps(1.0);
390     __m128           two     = _mm_set1_ps(2.0);
391     x                = xx[0];
392     f                = ff[0];
393
394     nri              = nlist->nri;
395     iinr             = nlist->iinr;
396     jindex           = nlist->jindex;
397     jjnr             = nlist->jjnr;
398     shiftidx         = nlist->shift;
399     gid              = nlist->gid;
400     shiftvec         = fr->shift_vec[0];
401     fshift           = fr->fshift[0];
402     nvdwtype         = fr->ntype;
403     vdwparam         = fr->nbfp;
404     vdwtype          = mdatoms->typeA;
405
406     /* Avoid stupid compiler warnings */
407     jnrA = jnrB = jnrC = jnrD = 0;
408     j_coord_offsetA = 0;
409     j_coord_offsetB = 0;
410     j_coord_offsetC = 0;
411     j_coord_offsetD = 0;
412
413     outeriter        = 0;
414     inneriter        = 0;
415
416     for(iidx=0;iidx<4*DIM;iidx++)
417     {
418         scratch[iidx] = 0.0;
419     }  
420
421     /* Start outer loop over neighborlists */
422     for(iidx=0; iidx<nri; iidx++)
423     {
424         /* Load shift vector for this list */
425         i_shift_offset   = DIM*shiftidx[iidx];
426
427         /* Load limits for loop over neighbors */
428         j_index_start    = jindex[iidx];
429         j_index_end      = jindex[iidx+1];
430
431         /* Get outer coordinate index */
432         inr              = iinr[iidx];
433         i_coord_offset   = DIM*inr;
434
435         /* Load i particle coords and add shift vector */
436         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
437         
438         fix0             = _mm_setzero_ps();
439         fiy0             = _mm_setzero_ps();
440         fiz0             = _mm_setzero_ps();
441
442         /* Load parameters for i particles */
443         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
444
445         /* Start inner kernel loop */
446         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
447         {
448
449             /* Get j neighbor index, and coordinate index */
450             jnrA             = jjnr[jidx];
451             jnrB             = jjnr[jidx+1];
452             jnrC             = jjnr[jidx+2];
453             jnrD             = jjnr[jidx+3];
454             j_coord_offsetA  = DIM*jnrA;
455             j_coord_offsetB  = DIM*jnrB;
456             j_coord_offsetC  = DIM*jnrC;
457             j_coord_offsetD  = DIM*jnrD;
458
459             /* load j atom coordinates */
460             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
461                                               x+j_coord_offsetC,x+j_coord_offsetD,
462                                               &jx0,&jy0,&jz0);
463
464             /* Calculate displacement vector */
465             dx00             = _mm_sub_ps(ix0,jx0);
466             dy00             = _mm_sub_ps(iy0,jy0);
467             dz00             = _mm_sub_ps(iz0,jz0);
468
469             /* Calculate squared distance and things based on it */
470             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
471
472             rinvsq00         = sse2_inv_f(rsq00);
473
474             /* Load parameters for j particles */
475             vdwjidx0A        = 2*vdwtype[jnrA+0];
476             vdwjidx0B        = 2*vdwtype[jnrB+0];
477             vdwjidx0C        = 2*vdwtype[jnrC+0];
478             vdwjidx0D        = 2*vdwtype[jnrD+0];
479
480             /**************************
481              * CALCULATE INTERACTIONS *
482              **************************/
483
484             /* Compute parameters for interactions between i and j atoms */
485             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
486                                          vdwparam+vdwioffset0+vdwjidx0B,
487                                          vdwparam+vdwioffset0+vdwjidx0C,
488                                          vdwparam+vdwioffset0+vdwjidx0D,
489                                          &c6_00,&c12_00);
490
491             /* LENNARD-JONES DISPERSION/REPULSION */
492
493             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
494             fvdw             = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(c12_00,rinvsix),c6_00),_mm_mul_ps(rinvsix,rinvsq00));
495
496             fscal            = fvdw;
497
498             /* Calculate temporary vectorial force */
499             tx               = _mm_mul_ps(fscal,dx00);
500             ty               = _mm_mul_ps(fscal,dy00);
501             tz               = _mm_mul_ps(fscal,dz00);
502
503             /* Update vectorial force */
504             fix0             = _mm_add_ps(fix0,tx);
505             fiy0             = _mm_add_ps(fiy0,ty);
506             fiz0             = _mm_add_ps(fiz0,tz);
507
508             fjptrA             = f+j_coord_offsetA;
509             fjptrB             = f+j_coord_offsetB;
510             fjptrC             = f+j_coord_offsetC;
511             fjptrD             = f+j_coord_offsetD;
512             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
513             
514             /* Inner loop uses 27 flops */
515         }
516
517         if(jidx<j_index_end)
518         {
519
520             /* Get j neighbor index, and coordinate index */
521             jnrlistA         = jjnr[jidx];
522             jnrlistB         = jjnr[jidx+1];
523             jnrlistC         = jjnr[jidx+2];
524             jnrlistD         = jjnr[jidx+3];
525             /* Sign of each element will be negative for non-real atoms.
526              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
527              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
528              */
529             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
530             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
531             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
532             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
533             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
534             j_coord_offsetA  = DIM*jnrA;
535             j_coord_offsetB  = DIM*jnrB;
536             j_coord_offsetC  = DIM*jnrC;
537             j_coord_offsetD  = DIM*jnrD;
538
539             /* load j atom coordinates */
540             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
541                                               x+j_coord_offsetC,x+j_coord_offsetD,
542                                               &jx0,&jy0,&jz0);
543
544             /* Calculate displacement vector */
545             dx00             = _mm_sub_ps(ix0,jx0);
546             dy00             = _mm_sub_ps(iy0,jy0);
547             dz00             = _mm_sub_ps(iz0,jz0);
548
549             /* Calculate squared distance and things based on it */
550             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
551
552             rinvsq00         = sse2_inv_f(rsq00);
553
554             /* Load parameters for j particles */
555             vdwjidx0A        = 2*vdwtype[jnrA+0];
556             vdwjidx0B        = 2*vdwtype[jnrB+0];
557             vdwjidx0C        = 2*vdwtype[jnrC+0];
558             vdwjidx0D        = 2*vdwtype[jnrD+0];
559
560             /**************************
561              * CALCULATE INTERACTIONS *
562              **************************/
563
564             /* Compute parameters for interactions between i and j atoms */
565             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
566                                          vdwparam+vdwioffset0+vdwjidx0B,
567                                          vdwparam+vdwioffset0+vdwjidx0C,
568                                          vdwparam+vdwioffset0+vdwjidx0D,
569                                          &c6_00,&c12_00);
570
571             /* LENNARD-JONES DISPERSION/REPULSION */
572
573             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
574             fvdw             = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(c12_00,rinvsix),c6_00),_mm_mul_ps(rinvsix,rinvsq00));
575
576             fscal            = fvdw;
577
578             fscal            = _mm_andnot_ps(dummy_mask,fscal);
579
580             /* Calculate temporary vectorial force */
581             tx               = _mm_mul_ps(fscal,dx00);
582             ty               = _mm_mul_ps(fscal,dy00);
583             tz               = _mm_mul_ps(fscal,dz00);
584
585             /* Update vectorial force */
586             fix0             = _mm_add_ps(fix0,tx);
587             fiy0             = _mm_add_ps(fiy0,ty);
588             fiz0             = _mm_add_ps(fiz0,tz);
589
590             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
591             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
592             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
593             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
594             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
595             
596             /* Inner loop uses 27 flops */
597         }
598
599         /* End of innermost loop */
600
601         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
602                                               f+i_coord_offset,fshift+i_shift_offset);
603
604         /* Increment number of inner iterations */
605         inneriter                  += j_index_end - j_index_start;
606
607         /* Outer loop uses 6 flops */
608     }
609
610     /* Increment number of outer iterations */
611     outeriter        += nri;
612
613     /* Update outer/inner flops */
614
615     inc_nrnb(nrnb,eNR_NBKERNEL_VDW_F,outeriter*6 + inneriter*27);
616 }