Merge release-5-0 into master
[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  *
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34  */
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/legacyheaders/types/simple.h"
46 #include "gromacs/math/vec.h"
47 #include "gromacs/legacyheaders/nrnb.h"
48
49 #include "gromacs/simd/math_x86_sse2_single.h"
50 #include "kernelutil_x86_sse2_single.h"
51
52 /*
53  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_VF_sse2_single
54  * Electrostatics interaction: Ewald
55  * VdW interaction:            LJEwald
56  * Geometry:                   Particle-Particle
57  * Calculate force/pot:        PotentialAndForce
58  */
59 void
60 nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_VF_sse2_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     __m128           velec,felec,velecsum,facel,crf,krf,krf2;
91     real             *charge;
92     int              nvdwtype;
93     __m128           rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
94     int              *vdwtype;
95     real             *vdwparam;
96     __m128           one_sixth   = _mm_set1_ps(1.0/6.0);
97     __m128           one_twelfth = _mm_set1_ps(1.0/12.0);
98     __m128           c6grid_00;
99     __m128           ewclj,ewclj2,ewclj6,ewcljrsq,poly,exponent,f6A,f6B,sh_lj_ewald;
100     real             *vdwgridparam;
101     __m128           one_half = _mm_set1_ps(0.5);
102     __m128           minus_one = _mm_set1_ps(-1.0);
103     __m128i          ewitab;
104     __m128           ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace,ewtabF,ewtabFn,ewtabD,ewtabV;
105     real             *ewtab;
106     __m128           dummy_mask,cutoff_mask;
107     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
108     __m128           one     = _mm_set1_ps(1.0);
109     __m128           two     = _mm_set1_ps(2.0);
110     x                = xx[0];
111     f                = ff[0];
112
113     nri              = nlist->nri;
114     iinr             = nlist->iinr;
115     jindex           = nlist->jindex;
116     jjnr             = nlist->jjnr;
117     shiftidx         = nlist->shift;
118     gid              = nlist->gid;
119     shiftvec         = fr->shift_vec[0];
120     fshift           = fr->fshift[0];
121     facel            = _mm_set1_ps(fr->epsfac);
122     charge           = mdatoms->chargeA;
123     nvdwtype         = fr->ntype;
124     vdwparam         = fr->nbfp;
125     vdwtype          = mdatoms->typeA;
126     vdwgridparam     = fr->ljpme_c6grid;
127     sh_lj_ewald      = _mm_set1_ps(fr->ic->sh_lj_ewald);
128     ewclj            = _mm_set1_ps(fr->ewaldcoeff_lj);
129     ewclj2           = _mm_mul_ps(minus_one,_mm_mul_ps(ewclj,ewclj));
130
131     sh_ewald         = _mm_set1_ps(fr->ic->sh_ewald);
132     ewtab            = fr->ic->tabq_coul_FDV0;
133     ewtabscale       = _mm_set1_ps(fr->ic->tabq_scale);
134     ewtabhalfspace   = _mm_set1_ps(0.5/fr->ic->tabq_scale);
135
136     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
137     rcutoff_scalar   = fr->rcoulomb;
138     rcutoff          = _mm_set1_ps(rcutoff_scalar);
139     rcutoff2         = _mm_mul_ps(rcutoff,rcutoff);
140
141     sh_vdw_invrcut6  = _mm_set1_ps(fr->ic->sh_invrc6);
142     rvdw             = _mm_set1_ps(fr->rvdw);
143
144     /* Avoid stupid compiler warnings */
145     jnrA = jnrB = jnrC = jnrD = 0;
146     j_coord_offsetA = 0;
147     j_coord_offsetB = 0;
148     j_coord_offsetC = 0;
149     j_coord_offsetD = 0;
150
151     outeriter        = 0;
152     inneriter        = 0;
153
154     for(iidx=0;iidx<4*DIM;iidx++)
155     {
156         scratch[iidx] = 0.0;
157     }  
158
159     /* Start outer loop over neighborlists */
160     for(iidx=0; iidx<nri; iidx++)
161     {
162         /* Load shift vector for this list */
163         i_shift_offset   = DIM*shiftidx[iidx];
164
165         /* Load limits for loop over neighbors */
166         j_index_start    = jindex[iidx];
167         j_index_end      = jindex[iidx+1];
168
169         /* Get outer coordinate index */
170         inr              = iinr[iidx];
171         i_coord_offset   = DIM*inr;
172
173         /* Load i particle coords and add shift vector */
174         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
175         
176         fix0             = _mm_setzero_ps();
177         fiy0             = _mm_setzero_ps();
178         fiz0             = _mm_setzero_ps();
179
180         /* Load parameters for i particles */
181         iq0              = _mm_mul_ps(facel,_mm_load1_ps(charge+inr+0));
182         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
183
184         /* Reset potential sums */
185         velecsum         = _mm_setzero_ps();
186         vvdwsum          = _mm_setzero_ps();
187
188         /* Start inner kernel loop */
189         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
190         {
191
192             /* Get j neighbor index, and coordinate index */
193             jnrA             = jjnr[jidx];
194             jnrB             = jjnr[jidx+1];
195             jnrC             = jjnr[jidx+2];
196             jnrD             = jjnr[jidx+3];
197             j_coord_offsetA  = DIM*jnrA;
198             j_coord_offsetB  = DIM*jnrB;
199             j_coord_offsetC  = DIM*jnrC;
200             j_coord_offsetD  = DIM*jnrD;
201
202             /* load j atom coordinates */
203             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
204                                               x+j_coord_offsetC,x+j_coord_offsetD,
205                                               &jx0,&jy0,&jz0);
206
207             /* Calculate displacement vector */
208             dx00             = _mm_sub_ps(ix0,jx0);
209             dy00             = _mm_sub_ps(iy0,jy0);
210             dz00             = _mm_sub_ps(iz0,jz0);
211
212             /* Calculate squared distance and things based on it */
213             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
214
215             rinv00           = gmx_mm_invsqrt_ps(rsq00);
216
217             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
218
219             /* Load parameters for j particles */
220             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
221                                                               charge+jnrC+0,charge+jnrD+0);
222             vdwjidx0A        = 2*vdwtype[jnrA+0];
223             vdwjidx0B        = 2*vdwtype[jnrB+0];
224             vdwjidx0C        = 2*vdwtype[jnrC+0];
225             vdwjidx0D        = 2*vdwtype[jnrD+0];
226
227             /**************************
228              * CALCULATE INTERACTIONS *
229              **************************/
230
231             if (gmx_mm_any_lt(rsq00,rcutoff2))
232             {
233
234             r00              = _mm_mul_ps(rsq00,rinv00);
235
236             /* Compute parameters for interactions between i and j atoms */
237             qq00             = _mm_mul_ps(iq0,jq0);
238             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
239                                          vdwparam+vdwioffset0+vdwjidx0B,
240                                          vdwparam+vdwioffset0+vdwjidx0C,
241                                          vdwparam+vdwioffset0+vdwjidx0D,
242                                          &c6_00,&c12_00);
243             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
244                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
245                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
246                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
247
248             /* EWALD ELECTROSTATICS */
249
250             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
251             ewrt             = _mm_mul_ps(r00,ewtabscale);
252             ewitab           = _mm_cvttps_epi32(ewrt);
253             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
254             ewitab           = _mm_slli_epi32(ewitab,2);
255             ewtabF           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,0) );
256             ewtabD           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,1) );
257             ewtabV           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,2) );
258             ewtabFn          = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,3) );
259             _MM_TRANSPOSE4_PS(ewtabF,ewtabD,ewtabV,ewtabFn);
260             felec            = _mm_add_ps(ewtabF,_mm_mul_ps(eweps,ewtabD));
261             velec            = _mm_sub_ps(ewtabV,_mm_mul_ps(_mm_mul_ps(ewtabhalfspace,eweps),_mm_add_ps(ewtabF,felec)));
262             velec            = _mm_mul_ps(qq00,_mm_sub_ps(_mm_sub_ps(rinv00,sh_ewald),velec));
263             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
264
265             /* Analytical LJ-PME */
266             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
267             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
268             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
269             exponent         = gmx_simd_exp_r(ewcljrsq);
270             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
271             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
272             /* vvdw6 = [C6 - C6grid * (1-poly)]/r6 */
273             vvdw6            = _mm_mul_ps(_mm_sub_ps(c6_00,_mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly))),rinvsix);
274             vvdw12           = _mm_mul_ps(c12_00,_mm_mul_ps(rinvsix,rinvsix));
275             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) ,
276                                           _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));
277             /* fvdw = vvdw12/r - (vvdw6/r + (C6grid * exponent * beta^6)/r) */
278             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);
279
280             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
281
282             /* Update potential sum for this i atom from the interaction with this j atom. */
283             velec            = _mm_and_ps(velec,cutoff_mask);
284             velecsum         = _mm_add_ps(velecsum,velec);
285             vvdw             = _mm_and_ps(vvdw,cutoff_mask);
286             vvdwsum          = _mm_add_ps(vvdwsum,vvdw);
287
288             fscal            = _mm_add_ps(felec,fvdw);
289
290             fscal            = _mm_and_ps(fscal,cutoff_mask);
291
292             /* Calculate temporary vectorial force */
293             tx               = _mm_mul_ps(fscal,dx00);
294             ty               = _mm_mul_ps(fscal,dy00);
295             tz               = _mm_mul_ps(fscal,dz00);
296
297             /* Update vectorial force */
298             fix0             = _mm_add_ps(fix0,tx);
299             fiy0             = _mm_add_ps(fiy0,ty);
300             fiz0             = _mm_add_ps(fiz0,tz);
301
302             fjptrA             = f+j_coord_offsetA;
303             fjptrB             = f+j_coord_offsetB;
304             fjptrC             = f+j_coord_offsetC;
305             fjptrD             = f+j_coord_offsetD;
306             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
307             
308             }
309
310             /* Inner loop uses 82 flops */
311         }
312
313         if(jidx<j_index_end)
314         {
315
316             /* Get j neighbor index, and coordinate index */
317             jnrlistA         = jjnr[jidx];
318             jnrlistB         = jjnr[jidx+1];
319             jnrlistC         = jjnr[jidx+2];
320             jnrlistD         = jjnr[jidx+3];
321             /* Sign of each element will be negative for non-real atoms.
322              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
323              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
324              */
325             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
326             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
327             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
328             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
329             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
330             j_coord_offsetA  = DIM*jnrA;
331             j_coord_offsetB  = DIM*jnrB;
332             j_coord_offsetC  = DIM*jnrC;
333             j_coord_offsetD  = DIM*jnrD;
334
335             /* load j atom coordinates */
336             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
337                                               x+j_coord_offsetC,x+j_coord_offsetD,
338                                               &jx0,&jy0,&jz0);
339
340             /* Calculate displacement vector */
341             dx00             = _mm_sub_ps(ix0,jx0);
342             dy00             = _mm_sub_ps(iy0,jy0);
343             dz00             = _mm_sub_ps(iz0,jz0);
344
345             /* Calculate squared distance and things based on it */
346             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
347
348             rinv00           = gmx_mm_invsqrt_ps(rsq00);
349
350             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
351
352             /* Load parameters for j particles */
353             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
354                                                               charge+jnrC+0,charge+jnrD+0);
355             vdwjidx0A        = 2*vdwtype[jnrA+0];
356             vdwjidx0B        = 2*vdwtype[jnrB+0];
357             vdwjidx0C        = 2*vdwtype[jnrC+0];
358             vdwjidx0D        = 2*vdwtype[jnrD+0];
359
360             /**************************
361              * CALCULATE INTERACTIONS *
362              **************************/
363
364             if (gmx_mm_any_lt(rsq00,rcutoff2))
365             {
366
367             r00              = _mm_mul_ps(rsq00,rinv00);
368             r00              = _mm_andnot_ps(dummy_mask,r00);
369
370             /* Compute parameters for interactions between i and j atoms */
371             qq00             = _mm_mul_ps(iq0,jq0);
372             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
373                                          vdwparam+vdwioffset0+vdwjidx0B,
374                                          vdwparam+vdwioffset0+vdwjidx0C,
375                                          vdwparam+vdwioffset0+vdwjidx0D,
376                                          &c6_00,&c12_00);
377             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
378                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
379                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
380                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
381
382             /* EWALD ELECTROSTATICS */
383
384             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
385             ewrt             = _mm_mul_ps(r00,ewtabscale);
386             ewitab           = _mm_cvttps_epi32(ewrt);
387             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
388             ewitab           = _mm_slli_epi32(ewitab,2);
389             ewtabF           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,0) );
390             ewtabD           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,1) );
391             ewtabV           = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,2) );
392             ewtabFn          = _mm_load_ps( ewtab + gmx_mm_extract_epi32(ewitab,3) );
393             _MM_TRANSPOSE4_PS(ewtabF,ewtabD,ewtabV,ewtabFn);
394             felec            = _mm_add_ps(ewtabF,_mm_mul_ps(eweps,ewtabD));
395             velec            = _mm_sub_ps(ewtabV,_mm_mul_ps(_mm_mul_ps(ewtabhalfspace,eweps),_mm_add_ps(ewtabF,felec)));
396             velec            = _mm_mul_ps(qq00,_mm_sub_ps(_mm_sub_ps(rinv00,sh_ewald),velec));
397             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
398
399             /* Analytical LJ-PME */
400             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
401             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
402             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
403             exponent         = gmx_simd_exp_r(ewcljrsq);
404             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
405             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
406             /* vvdw6 = [C6 - C6grid * (1-poly)]/r6 */
407             vvdw6            = _mm_mul_ps(_mm_sub_ps(c6_00,_mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly))),rinvsix);
408             vvdw12           = _mm_mul_ps(c12_00,_mm_mul_ps(rinvsix,rinvsix));
409             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) ,
410                                           _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));
411             /* fvdw = vvdw12/r - (vvdw6/r + (C6grid * exponent * beta^6)/r) */
412             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);
413
414             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
415
416             /* Update potential sum for this i atom from the interaction with this j atom. */
417             velec            = _mm_and_ps(velec,cutoff_mask);
418             velec            = _mm_andnot_ps(dummy_mask,velec);
419             velecsum         = _mm_add_ps(velecsum,velec);
420             vvdw             = _mm_and_ps(vvdw,cutoff_mask);
421             vvdw             = _mm_andnot_ps(dummy_mask,vvdw);
422             vvdwsum          = _mm_add_ps(vvdwsum,vvdw);
423
424             fscal            = _mm_add_ps(felec,fvdw);
425
426             fscal            = _mm_and_ps(fscal,cutoff_mask);
427
428             fscal            = _mm_andnot_ps(dummy_mask,fscal);
429
430             /* Calculate temporary vectorial force */
431             tx               = _mm_mul_ps(fscal,dx00);
432             ty               = _mm_mul_ps(fscal,dy00);
433             tz               = _mm_mul_ps(fscal,dz00);
434
435             /* Update vectorial force */
436             fix0             = _mm_add_ps(fix0,tx);
437             fiy0             = _mm_add_ps(fiy0,ty);
438             fiz0             = _mm_add_ps(fiz0,tz);
439
440             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
441             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
442             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
443             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
444             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
445             
446             }
447
448             /* Inner loop uses 83 flops */
449         }
450
451         /* End of innermost loop */
452
453         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
454                                               f+i_coord_offset,fshift+i_shift_offset);
455
456         ggid                        = gid[iidx];
457         /* Update potential energies */
458         gmx_mm_update_1pot_ps(velecsum,kernel_data->energygrp_elec+ggid);
459         gmx_mm_update_1pot_ps(vvdwsum,kernel_data->energygrp_vdw+ggid);
460
461         /* Increment number of inner iterations */
462         inneriter                  += j_index_end - j_index_start;
463
464         /* Outer loop uses 9 flops */
465     }
466
467     /* Increment number of outer iterations */
468     outeriter        += nri;
469
470     /* Update outer/inner flops */
471
472     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_VF,outeriter*9 + inneriter*83);
473 }
474 /*
475  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_F_sse2_single
476  * Electrostatics interaction: Ewald
477  * VdW interaction:            LJEwald
478  * Geometry:                   Particle-Particle
479  * Calculate force/pot:        Force
480  */
481 void
482 nb_kernel_ElecEwSh_VdwLJEwSh_GeomP1P1_F_sse2_single
483                     (t_nblist                    * gmx_restrict       nlist,
484                      rvec                        * gmx_restrict          xx,
485                      rvec                        * gmx_restrict          ff,
486                      t_forcerec                  * gmx_restrict          fr,
487                      t_mdatoms                   * gmx_restrict     mdatoms,
488                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
489                      t_nrnb                      * gmx_restrict        nrnb)
490 {
491     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or 
492      * just 0 for non-waters.
493      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
494      * jnr indices corresponding to data put in the four positions in the SIMD register.
495      */
496     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
497     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
498     int              jnrA,jnrB,jnrC,jnrD;
499     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
500     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
501     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
502     real             rcutoff_scalar;
503     real             *shiftvec,*fshift,*x,*f;
504     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
505     real             scratch[4*DIM];
506     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
507     int              vdwioffset0;
508     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
509     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
510     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
511     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
512     __m128           velec,felec,velecsum,facel,crf,krf,krf2;
513     real             *charge;
514     int              nvdwtype;
515     __m128           rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,sh_vdw_invrcut6;
516     int              *vdwtype;
517     real             *vdwparam;
518     __m128           one_sixth   = _mm_set1_ps(1.0/6.0);
519     __m128           one_twelfth = _mm_set1_ps(1.0/12.0);
520     __m128           c6grid_00;
521     __m128           ewclj,ewclj2,ewclj6,ewcljrsq,poly,exponent,f6A,f6B,sh_lj_ewald;
522     real             *vdwgridparam;
523     __m128           one_half = _mm_set1_ps(0.5);
524     __m128           minus_one = _mm_set1_ps(-1.0);
525     __m128i          ewitab;
526     __m128           ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace,ewtabF,ewtabFn,ewtabD,ewtabV;
527     real             *ewtab;
528     __m128           dummy_mask,cutoff_mask;
529     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
530     __m128           one     = _mm_set1_ps(1.0);
531     __m128           two     = _mm_set1_ps(2.0);
532     x                = xx[0];
533     f                = ff[0];
534
535     nri              = nlist->nri;
536     iinr             = nlist->iinr;
537     jindex           = nlist->jindex;
538     jjnr             = nlist->jjnr;
539     shiftidx         = nlist->shift;
540     gid              = nlist->gid;
541     shiftvec         = fr->shift_vec[0];
542     fshift           = fr->fshift[0];
543     facel            = _mm_set1_ps(fr->epsfac);
544     charge           = mdatoms->chargeA;
545     nvdwtype         = fr->ntype;
546     vdwparam         = fr->nbfp;
547     vdwtype          = mdatoms->typeA;
548     vdwgridparam     = fr->ljpme_c6grid;
549     sh_lj_ewald      = _mm_set1_ps(fr->ic->sh_lj_ewald);
550     ewclj            = _mm_set1_ps(fr->ewaldcoeff_lj);
551     ewclj2           = _mm_mul_ps(minus_one,_mm_mul_ps(ewclj,ewclj));
552
553     sh_ewald         = _mm_set1_ps(fr->ic->sh_ewald);
554     ewtab            = fr->ic->tabq_coul_F;
555     ewtabscale       = _mm_set1_ps(fr->ic->tabq_scale);
556     ewtabhalfspace   = _mm_set1_ps(0.5/fr->ic->tabq_scale);
557
558     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
559     rcutoff_scalar   = fr->rcoulomb;
560     rcutoff          = _mm_set1_ps(rcutoff_scalar);
561     rcutoff2         = _mm_mul_ps(rcutoff,rcutoff);
562
563     sh_vdw_invrcut6  = _mm_set1_ps(fr->ic->sh_invrc6);
564     rvdw             = _mm_set1_ps(fr->rvdw);
565
566     /* Avoid stupid compiler warnings */
567     jnrA = jnrB = jnrC = jnrD = 0;
568     j_coord_offsetA = 0;
569     j_coord_offsetB = 0;
570     j_coord_offsetC = 0;
571     j_coord_offsetD = 0;
572
573     outeriter        = 0;
574     inneriter        = 0;
575
576     for(iidx=0;iidx<4*DIM;iidx++)
577     {
578         scratch[iidx] = 0.0;
579     }  
580
581     /* Start outer loop over neighborlists */
582     for(iidx=0; iidx<nri; iidx++)
583     {
584         /* Load shift vector for this list */
585         i_shift_offset   = DIM*shiftidx[iidx];
586
587         /* Load limits for loop over neighbors */
588         j_index_start    = jindex[iidx];
589         j_index_end      = jindex[iidx+1];
590
591         /* Get outer coordinate index */
592         inr              = iinr[iidx];
593         i_coord_offset   = DIM*inr;
594
595         /* Load i particle coords and add shift vector */
596         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
597         
598         fix0             = _mm_setzero_ps();
599         fiy0             = _mm_setzero_ps();
600         fiz0             = _mm_setzero_ps();
601
602         /* Load parameters for i particles */
603         iq0              = _mm_mul_ps(facel,_mm_load1_ps(charge+inr+0));
604         vdwioffset0      = 2*nvdwtype*vdwtype[inr+0];
605
606         /* Start inner kernel loop */
607         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
608         {
609
610             /* Get j neighbor index, and coordinate index */
611             jnrA             = jjnr[jidx];
612             jnrB             = jjnr[jidx+1];
613             jnrC             = jjnr[jidx+2];
614             jnrD             = jjnr[jidx+3];
615             j_coord_offsetA  = DIM*jnrA;
616             j_coord_offsetB  = DIM*jnrB;
617             j_coord_offsetC  = DIM*jnrC;
618             j_coord_offsetD  = DIM*jnrD;
619
620             /* load j atom coordinates */
621             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
622                                               x+j_coord_offsetC,x+j_coord_offsetD,
623                                               &jx0,&jy0,&jz0);
624
625             /* Calculate displacement vector */
626             dx00             = _mm_sub_ps(ix0,jx0);
627             dy00             = _mm_sub_ps(iy0,jy0);
628             dz00             = _mm_sub_ps(iz0,jz0);
629
630             /* Calculate squared distance and things based on it */
631             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
632
633             rinv00           = gmx_mm_invsqrt_ps(rsq00);
634
635             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
636
637             /* Load parameters for j particles */
638             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
639                                                               charge+jnrC+0,charge+jnrD+0);
640             vdwjidx0A        = 2*vdwtype[jnrA+0];
641             vdwjidx0B        = 2*vdwtype[jnrB+0];
642             vdwjidx0C        = 2*vdwtype[jnrC+0];
643             vdwjidx0D        = 2*vdwtype[jnrD+0];
644
645             /**************************
646              * CALCULATE INTERACTIONS *
647              **************************/
648
649             if (gmx_mm_any_lt(rsq00,rcutoff2))
650             {
651
652             r00              = _mm_mul_ps(rsq00,rinv00);
653
654             /* Compute parameters for interactions between i and j atoms */
655             qq00             = _mm_mul_ps(iq0,jq0);
656             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
657                                          vdwparam+vdwioffset0+vdwjidx0B,
658                                          vdwparam+vdwioffset0+vdwjidx0C,
659                                          vdwparam+vdwioffset0+vdwjidx0D,
660                                          &c6_00,&c12_00);
661             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
662                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
663                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
664                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
665
666             /* EWALD ELECTROSTATICS */
667
668             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
669             ewrt             = _mm_mul_ps(r00,ewtabscale);
670             ewitab           = _mm_cvttps_epi32(ewrt);
671             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
672             gmx_mm_load_4pair_swizzle_ps(ewtab+gmx_mm_extract_epi32(ewitab,0),ewtab+gmx_mm_extract_epi32(ewitab,1),
673                                          ewtab+gmx_mm_extract_epi32(ewitab,2),ewtab+gmx_mm_extract_epi32(ewitab,3),
674                                          &ewtabF,&ewtabFn);
675             felec            = _mm_add_ps(_mm_mul_ps( _mm_sub_ps(one,eweps),ewtabF),_mm_mul_ps(eweps,ewtabFn));
676             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
677
678             /* Analytical LJ-PME */
679             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
680             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
681             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
682             exponent         = gmx_simd_exp_r(ewcljrsq);
683             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
684             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
685             /* f6A = 6 * C6grid * (1 - poly) */
686             f6A              = _mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly));
687             /* f6B = C6grid * exponent * beta^6 */
688             f6B              = _mm_mul_ps(_mm_mul_ps(c6grid_00,one_sixth),_mm_mul_ps(exponent,ewclj6));
689             /* fvdw = 12*C12/r13 - ((6*C6 - f6A)/r6 + f6B)/r */
690             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);
691
692             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
693
694             fscal            = _mm_add_ps(felec,fvdw);
695
696             fscal            = _mm_and_ps(fscal,cutoff_mask);
697
698             /* Calculate temporary vectorial force */
699             tx               = _mm_mul_ps(fscal,dx00);
700             ty               = _mm_mul_ps(fscal,dy00);
701             tz               = _mm_mul_ps(fscal,dz00);
702
703             /* Update vectorial force */
704             fix0             = _mm_add_ps(fix0,tx);
705             fiy0             = _mm_add_ps(fiy0,ty);
706             fiz0             = _mm_add_ps(fiz0,tz);
707
708             fjptrA             = f+j_coord_offsetA;
709             fjptrB             = f+j_coord_offsetB;
710             fjptrC             = f+j_coord_offsetC;
711             fjptrD             = f+j_coord_offsetD;
712             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
713             
714             }
715
716             /* Inner loop uses 62 flops */
717         }
718
719         if(jidx<j_index_end)
720         {
721
722             /* Get j neighbor index, and coordinate index */
723             jnrlistA         = jjnr[jidx];
724             jnrlistB         = jjnr[jidx+1];
725             jnrlistC         = jjnr[jidx+2];
726             jnrlistD         = jjnr[jidx+3];
727             /* Sign of each element will be negative for non-real atoms.
728              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
729              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
730              */
731             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
732             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
733             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
734             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
735             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
736             j_coord_offsetA  = DIM*jnrA;
737             j_coord_offsetB  = DIM*jnrB;
738             j_coord_offsetC  = DIM*jnrC;
739             j_coord_offsetD  = DIM*jnrD;
740
741             /* load j atom coordinates */
742             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
743                                               x+j_coord_offsetC,x+j_coord_offsetD,
744                                               &jx0,&jy0,&jz0);
745
746             /* Calculate displacement vector */
747             dx00             = _mm_sub_ps(ix0,jx0);
748             dy00             = _mm_sub_ps(iy0,jy0);
749             dz00             = _mm_sub_ps(iz0,jz0);
750
751             /* Calculate squared distance and things based on it */
752             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
753
754             rinv00           = gmx_mm_invsqrt_ps(rsq00);
755
756             rinvsq00         = _mm_mul_ps(rinv00,rinv00);
757
758             /* Load parameters for j particles */
759             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
760                                                               charge+jnrC+0,charge+jnrD+0);
761             vdwjidx0A        = 2*vdwtype[jnrA+0];
762             vdwjidx0B        = 2*vdwtype[jnrB+0];
763             vdwjidx0C        = 2*vdwtype[jnrC+0];
764             vdwjidx0D        = 2*vdwtype[jnrD+0];
765
766             /**************************
767              * CALCULATE INTERACTIONS *
768              **************************/
769
770             if (gmx_mm_any_lt(rsq00,rcutoff2))
771             {
772
773             r00              = _mm_mul_ps(rsq00,rinv00);
774             r00              = _mm_andnot_ps(dummy_mask,r00);
775
776             /* Compute parameters for interactions between i and j atoms */
777             qq00             = _mm_mul_ps(iq0,jq0);
778             gmx_mm_load_4pair_swizzle_ps(vdwparam+vdwioffset0+vdwjidx0A,
779                                          vdwparam+vdwioffset0+vdwjidx0B,
780                                          vdwparam+vdwioffset0+vdwjidx0C,
781                                          vdwparam+vdwioffset0+vdwjidx0D,
782                                          &c6_00,&c12_00);
783             c6grid_00       = gmx_mm_load_4real_swizzle_ps(vdwgridparam+vdwioffset0+vdwjidx0A,
784                                                                vdwgridparam+vdwioffset0+vdwjidx0B,
785                                                                vdwgridparam+vdwioffset0+vdwjidx0C,
786                                                                vdwgridparam+vdwioffset0+vdwjidx0D);
787
788             /* EWALD ELECTROSTATICS */
789
790             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
791             ewrt             = _mm_mul_ps(r00,ewtabscale);
792             ewitab           = _mm_cvttps_epi32(ewrt);
793             eweps            = _mm_sub_ps(ewrt,_mm_cvtepi32_ps(ewitab));
794             gmx_mm_load_4pair_swizzle_ps(ewtab+gmx_mm_extract_epi32(ewitab,0),ewtab+gmx_mm_extract_epi32(ewitab,1),
795                                          ewtab+gmx_mm_extract_epi32(ewitab,2),ewtab+gmx_mm_extract_epi32(ewitab,3),
796                                          &ewtabF,&ewtabFn);
797             felec            = _mm_add_ps(_mm_mul_ps( _mm_sub_ps(one,eweps),ewtabF),_mm_mul_ps(eweps,ewtabFn));
798             felec            = _mm_mul_ps(_mm_mul_ps(qq00,rinv00),_mm_sub_ps(rinvsq00,felec));
799
800             /* Analytical LJ-PME */
801             rinvsix          = _mm_mul_ps(_mm_mul_ps(rinvsq00,rinvsq00),rinvsq00);
802             ewcljrsq         = _mm_mul_ps(ewclj2,rsq00);
803             ewclj6           = _mm_mul_ps(ewclj2,_mm_mul_ps(ewclj2,ewclj2));
804             exponent         = gmx_simd_exp_r(ewcljrsq);
805             /* poly = exp(-(beta*r)^2) * (1 + (beta*r)^2 + (beta*r)^4 /2) */
806             poly             = _mm_mul_ps(exponent,_mm_add_ps(_mm_sub_ps(one,ewcljrsq),_mm_mul_ps(_mm_mul_ps(ewcljrsq,ewcljrsq),one_half)));
807             /* f6A = 6 * C6grid * (1 - poly) */
808             f6A              = _mm_mul_ps(c6grid_00,_mm_sub_ps(one,poly));
809             /* f6B = C6grid * exponent * beta^6 */
810             f6B              = _mm_mul_ps(_mm_mul_ps(c6grid_00,one_sixth),_mm_mul_ps(exponent,ewclj6));
811             /* fvdw = 12*C12/r13 - ((6*C6 - f6A)/r6 + f6B)/r */
812             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);
813
814             cutoff_mask      = _mm_cmplt_ps(rsq00,rcutoff2);
815
816             fscal            = _mm_add_ps(felec,fvdw);
817
818             fscal            = _mm_and_ps(fscal,cutoff_mask);
819
820             fscal            = _mm_andnot_ps(dummy_mask,fscal);
821
822             /* Calculate temporary vectorial force */
823             tx               = _mm_mul_ps(fscal,dx00);
824             ty               = _mm_mul_ps(fscal,dy00);
825             tz               = _mm_mul_ps(fscal,dz00);
826
827             /* Update vectorial force */
828             fix0             = _mm_add_ps(fix0,tx);
829             fiy0             = _mm_add_ps(fiy0,ty);
830             fiz0             = _mm_add_ps(fiz0,tz);
831
832             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
833             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
834             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
835             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
836             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
837             
838             }
839
840             /* Inner loop uses 63 flops */
841         }
842
843         /* End of innermost loop */
844
845         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
846                                               f+i_coord_offset,fshift+i_shift_offset);
847
848         /* Increment number of inner iterations */
849         inneriter                  += j_index_end - j_index_start;
850
851         /* Outer loop uses 7 flops */
852     }
853
854     /* Increment number of outer iterations */
855     outeriter        += nri;
856
857     /* Update outer/inner flops */
858
859     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_F,outeriter*7 + inneriter*63);
860 }