599c0040fac552320afef49d81ab60ab04089751
[alexxy/gromacs.git] / src / gromacs / gmxlib / nonbonded / nb_kernel_sse2_single / nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_sse2_single.c
1 /*
2  * This file is part of the GROMACS molecular simulation package.
3  *
4  * Copyright (c) 2012,2013,2014, by the GROMACS development team, led by
5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
6  * and including many others, as listed in the AUTHORS file in the
7  * top-level source directory and at http://www.gromacs.org.
8  *
9  * GROMACS is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public License
11  * as published by the Free Software Foundation; either version 2.1
12  * of the License, or (at your option) any later version.
13  *
14  * GROMACS is distributed in the hope that it will be useful,
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17  * Lesser General Public License for more details.
18  *
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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_VdwLJEwSh_GeomP1P1_VF_sse2_single
52  * Electrostatics interaction: Ewald
53  * VdW interaction:            LJEwald
54  * Geometry:                   Particle-Particle
55  * Calculate force/pot:        PotentialAndForce
56  */
57 void
58 nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_VF_sse2_single
59                     (t_nblist                    * gmx_restrict       nlist,
60                      rvec                        * gmx_restrict          xx,
61                      rvec                        * gmx_restrict          ff,
62                      t_forcerec                  * gmx_restrict          fr,
63                      t_mdatoms                   * gmx_restrict     mdatoms,
64                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
65                      t_nrnb                      * gmx_restrict        nrnb)
66 {
67     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or 
68      * just 0 for non-waters.
69      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
70      * jnr indices corresponding to data put in the four positions in the SIMD register.
71      */
72     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
73     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
74     int              jnrA,jnrB,jnrC,jnrD;
75     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
76     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
77     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
78     real             rcutoff_scalar;
79     real             *shiftvec,*fshift,*x,*f;
80     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
81     real             scratch[4*DIM];
82     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
83     int              vdwioffset0;
84     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
85     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
86     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
87     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
88     __m128           velec,felec,velecsum,facel,crf,krf,krf2;
89     real             *charge;
90     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     __m128i          ewitab;
102     __m128           ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace,ewtabF,ewtabFn,ewtabD,ewtabV;
103     real             *ewtab;
104     __m128           dummy_mask,cutoff_mask;
105     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
106     __m128           one     = _mm_set1_ps(1.0);
107     __m128           two     = _mm_set1_ps(2.0);
108     x                = xx[0];
109     f                = ff[0];
110
111     nri              = nlist->nri;
112     iinr             = nlist->iinr;
113     jindex           = nlist->jindex;
114     jjnr             = nlist->jjnr;
115     shiftidx         = nlist->shift;
116     gid              = nlist->gid;
117     shiftvec         = fr->shift_vec[0];
118     fshift           = fr->fshift[0];
119     facel            = _mm_set1_ps(fr->epsfac);
120     charge           = mdatoms->chargeA;
121     nvdwtype         = fr->ntype;
122     vdwparam         = fr->nbfp;
123     vdwtype          = mdatoms->typeA;
124     vdwgridparam     = fr->ljpme_c6grid;
125     sh_lj_ewald      = _mm_set1_ps(fr->ic->sh_lj_ewald);
126     ewclj            = _mm_set1_ps(fr->ewaldcoeff_lj);
127     ewclj2           = _mm_mul_ps(minus_one,_mm_mul_ps(ewclj,ewclj));
128
129     sh_ewald         = _mm_set1_ps(fr->ic->sh_ewald);
130     ewtab            = fr->ic->tabq_coul_FDV0;
131     ewtabscale       = _mm_set1_ps(fr->ic->tabq_scale);
132     ewtabhalfspace   = _mm_set1_ps(0.5/fr->ic->tabq_scale);
133
134     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
135     rcutoff_scalar   = fr->rcoulomb;
136     rcutoff          = _mm_set1_ps(rcutoff_scalar);
137     rcutoff2         = _mm_mul_ps(rcutoff,rcutoff);
138
139     sh_vdw_invrcut6  = _mm_set1_ps(fr->ic->sh_invrc6);
140     rvdw             = _mm_set1_ps(fr->rvdw);
141
142     /* Avoid stupid compiler warnings */
143     jnrA = jnrB = jnrC = jnrD = 0;
144     j_coord_offsetA = 0;
145     j_coord_offsetB = 0;
146     j_coord_offsetC = 0;
147     j_coord_offsetD = 0;
148
149     outeriter        = 0;
150     inneriter        = 0;
151
152     for(iidx=0;iidx<4*DIM;iidx++)
153     {
154         scratch[iidx] = 0.0;
155     }  
156
157     /* Start outer loop over neighborlists */
158     for(iidx=0; iidx<nri; iidx++)
159     {
160         /* Load shift vector for this list */
161         i_shift_offset   = DIM*shiftidx[iidx];
162
163         /* Load limits for loop over neighbors */
164         j_index_start    = jindex[iidx];
165         j_index_end      = jindex[iidx+1];
166
167         /* Get outer coordinate index */
168         inr              = iinr[iidx];
169         i_coord_offset   = DIM*inr;
170
171         /* Load i particle coords and add shift vector */
172         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
173         
174         fix0             = _mm_setzero_ps();
175         fiy0             = _mm_setzero_ps();
176         fiz0             = _mm_setzero_ps();
177
178         /* Load parameters for i particles */
179         iq0              = _mm_mul_ps(facel,_mm_load1_ps(charge+inr+0));
180         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
181
182         /* Reset potential sums */
183         velecsum         = _mm_setzero_ps();
184         vvdwsum          = _mm_setzero_ps();
185
186         /* Start inner kernel loop */
187         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
188         {
189
190             /* Get j neighbor index, and coordinate index */
191             jnrA             = jjnr[jidx];
192             jnrB             = jjnr[jidx+1];
193             jnrC             = jjnr[jidx+2];
194             jnrD             = jjnr[jidx+3];
195             j_coord_offsetA  = DIM*jnrA;
196             j_coord_offsetB  = DIM*jnrB;
197             j_coord_offsetC  = DIM*jnrC;
198             j_coord_offsetD  = DIM*jnrD;
199
200             /* load j atom coordinates */
201             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
202                                               x+j_coord_offsetC,x+j_coord_offsetD,
203                                               &jx0,&jy0,&jz0);
204
205             /* Calculate displacement vector */
206             dx00             = _mm_sub_ps(ix0,jx0);
207             dy00             = _mm_sub_ps(iy0,jy0);
208             dz00             = _mm_sub_ps(iz0,jz0);
209
210             /* Calculate squared distance and things based on it */
211             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
212
213             rinv00           = gmx_mm_invsqrt_ps(rsq00);
214
215             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
216
217             /* Load parameters for j particles */
218             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
219                                                               charge+jnrC+0,charge+jnrD+0);
220             vdwjidx0A        = 2*vdwtype[jnrA+0];
221             vdwjidx0B        = 2*vdwtype[jnrB+0];
222             vdwjidx0C        = 2*vdwtype[jnrC+0];
223             vdwjidx0D        = 2*vdwtype[jnrD+0];
224
225             /**************************
226              * CALCULATE INTERACTIONS *
227              **************************/
228
229             if (gmx_mm_any_lt(rsq00,rcutoff2))
230             {
231
232             r00              = _mm_mul_ps(rsq00,rinv00);
233
234             /* Compute parameters for interactions between i and j atoms */
235             qq00             = _mm_mul_ps(iq0,jq0);
236             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
237                                          vdwparam+vdwioffset0+vdwjidx0B,
238                                          vdwparam+vdwioffset0+vdwjidx0C,
239                                          vdwparam+vdwioffset0+vdwjidx0D,
240                                          &c6_00,&c12_00);
241             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
242                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
243                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
244                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
245
246             /* EWALD ELECTROSTATICS */
247
248             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
249             ewrt             = _mm_mul_ps(r00,ewtabscale);
250             ewitab           = _mm_cvttps_epi32(ewrt);
251             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
252             ewitab           = _mm_slli_epi32(ewitab,2);
253             ewtabF           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,0) );
254             ewtabD           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,1) );
255             ewtabV           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,2) );
256             ewtabFn          = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,3) );
257             _MM_TRANSPOSE4_PS(ewtabF,ewtabD,ewtabV,ewtabFn);
258             felec            = _mm_add_ps(ewtabF,_mm_mul_ps(eweps,ewtabD));
259             velec            = _mm_sub_ps(ewtabV,_mm_mul_ps(_mm_mul_ps(ewtabhalfspace,eweps),_mm_add_ps(ewtabF,felec)));
260             velec            = _mm_mul_ps(qq00,_mm_sub_ps(_mm_sub_ps(rinv00,sh_ewald),velec));
261             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
262
263             /* Analytical LJ-PME */
264             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
265             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
266             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
267             exponent         = gmx_simd_exp_r(ewcljrsq);
268             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
269             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
270             /* vvdw6 = [C6 - C6grid * (1-poly)]/r6 */
271             vvdw6            = _mm_mul_ps(_mm_sub_ps(c6_00,_mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly))),rinvsix);
272             vvdw12           = _mm_mul_ps(c12_00,_mm_mul_ps(rinvsix,rinvsix));
273             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) ,
274                                           _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));
275             /* fvdw = vvdw12/r - (vvdw6/r + (C6grid * exponent * beta^6)/r) */
276             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);
277
278             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
279
280             /* Update potential sum for this i atom from the interaction with this j atom. */
281             velec            = _mm_and_ps(velec,cutoff_mask);
282             velecsum         = _mm_add_ps(velecsum,velec);
283             vvdw             = _mm_and_ps(vvdw,cutoff_mask);
284             vvdwsum          = _mm_add_ps(vvdwsum,vvdw);
285
286             fscal            = _mm_add_ps(felec,fvdw);
287
288             fscal            = _mm_and_ps(fscal,cutoff_mask);
289
290             /* Calculate temporary vectorial force */
291             tx               = _mm_mul_ps(fscal,dx00);
292             ty               = _mm_mul_ps(fscal,dy00);
293             tz               = _mm_mul_ps(fscal,dz00);
294
295             /* Update vectorial force */
296             fix0             = _mm_add_ps(fix0,tx);
297             fiy0             = _mm_add_ps(fiy0,ty);
298             fiz0             = _mm_add_ps(fiz0,tz);
299
300             fjptrA             = f+j_coord_offsetA;
301             fjptrB             = f+j_coord_offsetB;
302             fjptrC             = f+j_coord_offsetC;
303             fjptrD             = f+j_coord_offsetD;
304             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
305             
306             }
307
308             /* Inner loop uses 82 flops */
309         }
310
311         if(jidx<j_index_end)
312         {
313
314             /* Get j neighbor index, and coordinate index */
315             jnrlistA         = jjnr[jidx];
316             jnrlistB         = jjnr[jidx+1];
317             jnrlistC         = jjnr[jidx+2];
318             jnrlistD         = jjnr[jidx+3];
319             /* Sign of each element will be negative for non-real atoms.
320              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
321              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
322              */
323             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
324             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
325             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
326             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
327             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
328             j_coord_offsetA  = DIM*jnrA;
329             j_coord_offsetB  = DIM*jnrB;
330             j_coord_offsetC  = DIM*jnrC;
331             j_coord_offsetD  = DIM*jnrD;
332
333             /* load j atom coordinates */
334             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
335                                               x+j_coord_offsetC,x+j_coord_offsetD,
336                                               &jx0,&jy0,&jz0);
337
338             /* Calculate displacement vector */
339             dx00             = _mm_sub_ps(ix0,jx0);
340             dy00             = _mm_sub_ps(iy0,jy0);
341             dz00             = _mm_sub_ps(iz0,jz0);
342
343             /* Calculate squared distance and things based on it */
344             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
345
346             rinv00           = gmx_mm_invsqrt_ps(rsq00);
347
348             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
349
350             /* Load parameters for j particles */
351             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
352                                                               charge+jnrC+0,charge+jnrD+0);
353             vdwjidx0A        = 2*vdwtype[jnrA+0];
354             vdwjidx0B        = 2*vdwtype[jnrB+0];
355             vdwjidx0C        = 2*vdwtype[jnrC+0];
356             vdwjidx0D        = 2*vdwtype[jnrD+0];
357
358             /**************************
359              * CALCULATE INTERACTIONS *
360              **************************/
361
362             if (gmx_mm_any_lt(rsq00,rcutoff2))
363             {
364
365             r00              = _mm_mul_ps(rsq00,rinv00);
366             r00              = _mm_andnot_ps(dummy_mask,r00);
367
368             /* Compute parameters for interactions between i and j atoms */
369             qq00             = _mm_mul_ps(iq0,jq0);
370             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
371                                          vdwparam+vdwioffset0+vdwjidx0B,
372                                          vdwparam+vdwioffset0+vdwjidx0C,
373                                          vdwparam+vdwioffset0+vdwjidx0D,
374                                          &c6_00,&c12_00);
375             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
376                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
377                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
378                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
379
380             /* EWALD ELECTROSTATICS */
381
382             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
383             ewrt             = _mm_mul_ps(r00,ewtabscale);
384             ewitab           = _mm_cvttps_epi32(ewrt);
385             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
386             ewitab           = _mm_slli_epi32(ewitab,2);
387             ewtabF           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,0) );
388             ewtabD           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,1) );
389             ewtabV           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,2) );
390             ewtabFn          = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,3) );
391             _MM_TRANSPOSE4_PS(ewtabF,ewtabD,ewtabV,ewtabFn);
392             felec            = _mm_add_ps(ewtabF,_mm_mul_ps(eweps,ewtabD));
393             velec            = _mm_sub_ps(ewtabV,_mm_mul_ps(_mm_mul_ps(ewtabhalfspace,eweps),_mm_add_ps(ewtabF,felec)));
394             velec            = _mm_mul_ps(qq00,_mm_sub_ps(_mm_sub_ps(rinv00,sh_ewald),velec));
395             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
396
397             /* Analytical LJ-PME */
398             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
399             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
400             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
401             exponent         = gmx_simd_exp_r(ewcljrsq);
402             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
403             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
404             /* vvdw6 = [C6 - C6grid * (1-poly)]/r6 */
405             vvdw6            = _mm_mul_ps(_mm_sub_ps(c6_00,_mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly))),rinvsix);
406             vvdw12           = _mm_mul_ps(c12_00,_mm_mul_ps(rinvsix,rinvsix));
407             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) ,
408                                           _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));
409             /* fvdw = vvdw12/r - (vvdw6/r + (C6grid * exponent * beta^6)/r) */
410             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);
411
412             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
413
414             /* Update potential sum for this i atom from the interaction with this j atom. */
415             velec            = _mm_and_ps(velec,cutoff_mask);
416             velec            = _mm_andnot_ps(dummy_mask,velec);
417             velecsum         = _mm_add_ps(velecsum,velec);
418             vvdw             = _mm_and_ps(vvdw,cutoff_mask);
419             vvdw             = _mm_andnot_ps(dummy_mask,vvdw);
420             vvdwsum          = _mm_add_ps(vvdwsum,vvdw);
421
422             fscal            = _mm_add_ps(felec,fvdw);
423
424             fscal            = _mm_and_ps(fscal,cutoff_mask);
425
426             fscal            = _mm_andnot_ps(dummy_mask,fscal);
427
428             /* Calculate temporary vectorial force */
429             tx               = _mm_mul_ps(fscal,dx00);
430             ty               = _mm_mul_ps(fscal,dy00);
431             tz               = _mm_mul_ps(fscal,dz00);
432
433             /* Update vectorial force */
434             fix0             = _mm_add_ps(fix0,tx);
435             fiy0             = _mm_add_ps(fiy0,ty);
436             fiz0             = _mm_add_ps(fiz0,tz);
437
438             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
439             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
440             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
441             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
442             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
443             
444             }
445
446             /* Inner loop uses 83 flops */
447         }
448
449         /* End of innermost loop */
450
451         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
452                                               f+i_coord_offset,fshift+i_shift_offset);
453
454         ggid                        = gid[iidx];
455         /* Update potential energies */
456         gmx_mm_update_1pot_ps(velecsum,kernel_data->energygrp_elec+ggid);
457         gmx_mm_update_1pot_ps(vvdwsum,kernel_data->energygrp_vdw+ggid);
458
459         /* Increment number of inner iterations */
460         inneriter                  += j_index_end - j_index_start;
461
462         /* Outer loop uses 9 flops */
463     }
464
465     /* Increment number of outer iterations */
466     outeriter        += nri;
467
468     /* Update outer/inner flops */
469
470     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_VF,outeriter*9 + inneriter*83);
471 }
472 /*
473  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_F_sse2_single
474  * Electrostatics interaction: Ewald
475  * VdW interaction:            LJEwald
476  * Geometry:                   Particle-Particle
477  * Calculate force/pot:        Force
478  */
479 void
480 nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_F_sse2_single
481                     (t_nblist                    * gmx_restrict       nlist,
482                      rvec                        * gmx_restrict          xx,
483                      rvec                        * gmx_restrict          ff,
484                      t_forcerec                  * gmx_restrict          fr,
485                      t_mdatoms                   * gmx_restrict     mdatoms,
486                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
487                      t_nrnb                      * gmx_restrict        nrnb)
488 {
489     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or 
490      * just 0 for non-waters.
491      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
492      * jnr indices corresponding to data put in the four positions in the SIMD register.
493      */
494     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
495     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
496     int              jnrA,jnrB,jnrC,jnrD;
497     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
498     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
499     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
500     real             rcutoff_scalar;
501     real             *shiftvec,*fshift,*x,*f;
502     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
503     real             scratch[4*DIM];
504     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
505     int              vdwioffset0;
506     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
507     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
508     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
509     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
510     __m128           velec,felec,velecsum,facel,crf,krf,krf2;
511     real             *charge;
512     int              nvdwtype;
513     __m128           rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
514     int              *vdwtype;
515     real             *vdwparam;
516     __m128           one_sixth   = _mm_set1_ps(1.0/6.0);
517     __m128           one_twelfth = _mm_set1_ps(1.0/12.0);
518     __m128           c6grid_00;
519     __m128           ewclj,ewclj2,ewclj6,ewcljrsq,poly,exponent,f6A,f6B,sh_lj_ewald;
520     real             *vdwgridparam;
521     __m128           one_half = _mm_set1_ps(0.5);
522     __m128           minus_one = _mm_set1_ps(-1.0);
523     __m128i          ewitab;
524     __m128           ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace,ewtabF,ewtabFn,ewtabD,ewtabV;
525     real             *ewtab;
526     __m128           dummy_mask,cutoff_mask;
527     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
528     __m128           one     = _mm_set1_ps(1.0);
529     __m128           two     = _mm_set1_ps(2.0);
530     x                = xx[0];
531     f                = ff[0];
532
533     nri              = nlist->nri;
534     iinr             = nlist->iinr;
535     jindex           = nlist->jindex;
536     jjnr             = nlist->jjnr;
537     shiftidx         = nlist->shift;
538     gid              = nlist->gid;
539     shiftvec         = fr->shift_vec[0];
540     fshift           = fr->fshift[0];
541     facel            = _mm_set1_ps(fr->epsfac);
542     charge           = mdatoms->chargeA;
543     nvdwtype         = fr->ntype;
544     vdwparam         = fr->nbfp;
545     vdwtype          = mdatoms->typeA;
546     vdwgridparam     = fr->ljpme_c6grid;
547     sh_lj_ewald      = _mm_set1_ps(fr->ic->sh_lj_ewald);
548     ewclj            = _mm_set1_ps(fr->ewaldcoeff_lj);
549     ewclj2           = _mm_mul_ps(minus_one,_mm_mul_ps(ewclj,ewclj));
550
551     sh_ewald         = _mm_set1_ps(fr->ic->sh_ewald);
552     ewtab            = fr->ic->tabq_coul_F;
553     ewtabscale       = _mm_set1_ps(fr->ic->tabq_scale);
554     ewtabhalfspace   = _mm_set1_ps(0.5/fr->ic->tabq_scale);
555
556     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
557     rcutoff_scalar   = fr->rcoulomb;
558     rcutoff          = _mm_set1_ps(rcutoff_scalar);
559     rcutoff2         = _mm_mul_ps(rcutoff,rcutoff);
560
561     sh_vdw_invrcut6  = _mm_set1_ps(fr->ic->sh_invrc6);
562     rvdw             = _mm_set1_ps(fr->rvdw);
563
564     /* Avoid stupid compiler warnings */
565     jnrA = jnrB = jnrC = jnrD = 0;
566     j_coord_offsetA = 0;
567     j_coord_offsetB = 0;
568     j_coord_offsetC = 0;
569     j_coord_offsetD = 0;
570
571     outeriter        = 0;
572     inneriter        = 0;
573
574     for(iidx=0;iidx<4*DIM;iidx++)
575     {
576         scratch[iidx] = 0.0;
577     }  
578
579     /* Start outer loop over neighborlists */
580     for(iidx=0; iidx<nri; iidx++)
581     {
582         /* Load shift vector for this list */
583         i_shift_offset   = DIM*shiftidx[iidx];
584
585         /* Load limits for loop over neighbors */
586         j_index_start    = jindex[iidx];
587         j_index_end      = jindex[iidx+1];
588
589         /* Get outer coordinate index */
590         inr              = iinr[iidx];
591         i_coord_offset   = DIM*inr;
592
593         /* Load i particle coords and add shift vector */
594         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
595         
596         fix0             = _mm_setzero_ps();
597         fiy0             = _mm_setzero_ps();
598         fiz0             = _mm_setzero_ps();
599
600         /* Load parameters for i particles */
601         iq0              = _mm_mul_ps(facel,_mm_load1_ps(charge+inr+0));
602         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
603
604         /* Start inner kernel loop */
605         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
606         {
607
608             /* Get j neighbor index, and coordinate index */
609             jnrA             = jjnr[jidx];
610             jnrB             = jjnr[jidx+1];
611             jnrC             = jjnr[jidx+2];
612             jnrD             = jjnr[jidx+3];
613             j_coord_offsetA  = DIM*jnrA;
614             j_coord_offsetB  = DIM*jnrB;
615             j_coord_offsetC  = DIM*jnrC;
616             j_coord_offsetD  = DIM*jnrD;
617
618             /* load j atom coordinates */
619             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
620                                               x+j_coord_offsetC,x+j_coord_offsetD,
621                                               &jx0,&jy0,&jz0);
622
623             /* Calculate displacement vector */
624             dx00             = _mm_sub_ps(ix0,jx0);
625             dy00             = _mm_sub_ps(iy0,jy0);
626             dz00             = _mm_sub_ps(iz0,jz0);
627
628             /* Calculate squared distance and things based on it */
629             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
630
631             rinv00           = gmx_mm_invsqrt_ps(rsq00);
632
633             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
634
635             /* Load parameters for j particles */
636             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
637                                                               charge+jnrC+0,charge+jnrD+0);
638             vdwjidx0A        = 2*vdwtype[jnrA+0];
639             vdwjidx0B        = 2*vdwtype[jnrB+0];
640             vdwjidx0C        = 2*vdwtype[jnrC+0];
641             vdwjidx0D        = 2*vdwtype[jnrD+0];
642
643             /**************************
644              * CALCULATE INTERACTIONS *
645              **************************/
646
647             if (gmx_mm_any_lt(rsq00,rcutoff2))
648             {
649
650             r00              = _mm_mul_ps(rsq00,rinv00);
651
652             /* Compute parameters for interactions between i and j atoms */
653             qq00             = _mm_mul_ps(iq0,jq0);
654             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
655                                          vdwparam+vdwioffset0+vdwjidx0B,
656                                          vdwparam+vdwioffset0+vdwjidx0C,
657                                          vdwparam+vdwioffset0+vdwjidx0D,
658                                          &c6_00,&c12_00);
659             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
660                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
661                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
662                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
663
664             /* EWALD ELECTROSTATICS */
665
666             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
667             ewrt             = _mm_mul_ps(r00,ewtabscale);
668             ewitab           = _mm_cvttps_epi32(ewrt);
669             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
670             gmx_mm_load_4pair_swizzle_ps(ewtab+gmx_mm_extract_epi32(ewitab,0),ewtab+gmx_mm_extract_epi32(ewitab,1),
671                                          ewtab+gmx_mm_extract_epi32(ewitab,2),ewtab+gmx_mm_extract_epi32(ewitab,3),
672                                          &ewtabF,&ewtabFn);
673             felec            = _mm_add_ps(_mm_mul_ps( _mm_sub_ps(one,eweps),ewtabF),_mm_mul_ps(eweps,ewtabFn));
674             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
675
676             /* Analytical LJ-PME */
677             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
678             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
679             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
680             exponent         = gmx_simd_exp_r(ewcljrsq);
681             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
682             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
683             /* f6A = 6 * C6grid * (1 - poly) */
684             f6A              = _mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly));
685             /* f6B = C6grid * exponent * beta^6 */
686             f6B              = _mm_mul_ps(_mm_mul_ps(c6grid_00,one_sixth),_mm_mul_ps(exponent,ewclj6));
687             /* fvdw = 12*C12/r13 - ((6*C6 - f6A)/r6 + f6B)/r */
688             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);
689
690             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
691
692             fscal            = _mm_add_ps(felec,fvdw);
693
694             fscal            = _mm_and_ps(fscal,cutoff_mask);
695
696             /* Calculate temporary vectorial force */
697             tx               = _mm_mul_ps(fscal,dx00);
698             ty               = _mm_mul_ps(fscal,dy00);
699             tz               = _mm_mul_ps(fscal,dz00);
700
701             /* Update vectorial force */
702             fix0             = _mm_add_ps(fix0,tx);
703             fiy0             = _mm_add_ps(fiy0,ty);
704             fiz0             = _mm_add_ps(fiz0,tz);
705
706             fjptrA             = f+j_coord_offsetA;
707             fjptrB             = f+j_coord_offsetB;
708             fjptrC             = f+j_coord_offsetC;
709             fjptrD             = f+j_coord_offsetD;
710             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
711             
712             }
713
714             /* Inner loop uses 62 flops */
715         }
716
717         if(jidx<j_index_end)
718         {
719
720             /* Get j neighbor index, and coordinate index */
721             jnrlistA         = jjnr[jidx];
722             jnrlistB         = jjnr[jidx+1];
723             jnrlistC         = jjnr[jidx+2];
724             jnrlistD         = jjnr[jidx+3];
725             /* Sign of each element will be negative for non-real atoms.
726              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
727              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
728              */
729             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
730             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
731             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
732             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
733             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
734             j_coord_offsetA  = DIM*jnrA;
735             j_coord_offsetB  = DIM*jnrB;
736             j_coord_offsetC  = DIM*jnrC;
737             j_coord_offsetD  = DIM*jnrD;
738
739             /* load j atom coordinates */
740             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
741                                               x+j_coord_offsetC,x+j_coord_offsetD,
742                                               &jx0,&jy0,&jz0);
743
744             /* Calculate displacement vector */
745             dx00             = _mm_sub_ps(ix0,jx0);
746             dy00             = _mm_sub_ps(iy0,jy0);
747             dz00             = _mm_sub_ps(iz0,jz0);
748
749             /* Calculate squared distance and things based on it */
750             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
751
752             rinv00           = gmx_mm_invsqrt_ps(rsq00);
753
754             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
755
756             /* Load parameters for j particles */
757             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
758                                                               charge+jnrC+0,charge+jnrD+0);
759             vdwjidx0A        = 2*vdwtype[jnrA+0];
760             vdwjidx0B        = 2*vdwtype[jnrB+0];
761             vdwjidx0C        = 2*vdwtype[jnrC+0];
762             vdwjidx0D        = 2*vdwtype[jnrD+0];
763
764             /**************************
765              * CALCULATE INTERACTIONS *
766              **************************/
767
768             if (gmx_mm_any_lt(rsq00,rcutoff2))
769             {
770
771             r00              = _mm_mul_ps(rsq00,rinv00);
772             r00              = _mm_andnot_ps(dummy_mask,r00);
773
774             /* Compute parameters for interactions between i and j atoms */
775             qq00             = _mm_mul_ps(iq0,jq0);
776             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
777                                          vdwparam+vdwioffset0+vdwjidx0B,
778                                          vdwparam+vdwioffset0+vdwjidx0C,
779                                          vdwparam+vdwioffset0+vdwjidx0D,
780                                          &c6_00,&c12_00);
781             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
782                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
783                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
784                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
785
786             /* EWALD ELECTROSTATICS */
787
788             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
789             ewrt             = _mm_mul_ps(r00,ewtabscale);
790             ewitab           = _mm_cvttps_epi32(ewrt);
791             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
792             gmx_mm_load_4pair_swizzle_ps(ewtab+gmx_mm_extract_epi32(ewitab,0),ewtab+gmx_mm_extract_epi32(ewitab,1),
793                                          ewtab+gmx_mm_extract_epi32(ewitab,2),ewtab+gmx_mm_extract_epi32(ewitab,3),
794                                          &ewtabF,&ewtabFn);
795             felec            = _mm_add_ps(_mm_mul_ps( _mm_sub_ps(one,eweps),ewtabF),_mm_mul_ps(eweps,ewtabFn));
796             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
797
798             /* Analytical LJ-PME */
799             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
800             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
801             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
802             exponent         = gmx_simd_exp_r(ewcljrsq);
803             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
804             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
805             /* f6A = 6 * C6grid * (1 - poly) */
806             f6A              = _mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly));
807             /* f6B = C6grid * exponent * beta^6 */
808             f6B              = _mm_mul_ps(_mm_mul_ps(c6grid_00,one_sixth),_mm_mul_ps(exponent,ewclj6));
809             /* fvdw = 12*C12/r13 - ((6*C6 - f6A)/r6 + f6B)/r */
810             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);
811
812             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
813
814             fscal            = _mm_add_ps(felec,fvdw);
815
816             fscal            = _mm_and_ps(fscal,cutoff_mask);
817
818             fscal            = _mm_andnot_ps(dummy_mask,fscal);
819
820             /* Calculate temporary vectorial force */
821             tx               = _mm_mul_ps(fscal,dx00);
822             ty               = _mm_mul_ps(fscal,dy00);
823             tz               = _mm_mul_ps(fscal,dz00);
824
825             /* Update vectorial force */
826             fix0             = _mm_add_ps(fix0,tx);
827             fiy0             = _mm_add_ps(fiy0,ty);
828             fiz0             = _mm_add_ps(fiz0,tz);
829
830             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
831             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
832             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
833             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
834             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
835             
836             }
837
838             /* Inner loop uses 63 flops */
839         }
840
841         /* End of innermost loop */
842
843         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
844                                               f+i_coord_offset,fshift+i_shift_offset);
845
846         /* Increment number of inner iterations */
847         inneriter                  += j_index_end - j_index_start;
848
849         /* Outer loop uses 7 flops */
850     }
851
852     /* Increment number of outer iterations */
853     outeriter        += nri;
854
855     /* Update outer/inner flops */
856
857     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_F,outeriter*7 + inneriter*63);
858 }