Update copyright statements and change license to LGPL
[alexxy/gromacs.git] / src / gmxlib / nonbonded / nb_kernel_sse2_single / nb_kernel_ElecGB_VdwNone_GeomP1P1_sse2_single.c
1 /*
2  * This file is part of the GROMACS molecular simulation package.
3  *
4  * Copyright (c) 2012, by the GROMACS development team, led by
5  * David van der Spoel, Berk Hess, Erik Lindahl, and including many
6  * others, as listed in the AUTHORS file in the top-level source
7  * 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.
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34  */
35 /*
36  * Note: this file was generated by the GROMACS sse2_single kernel generator.
37  */
38 #ifdef HAVE_CONFIG_H
39 #include <config.h>
40 #endif
41
42 #include <math.h>
43
44 #include "../nb_kernel.h"
45 #include "types/simple.h"
46 #include "vec.h"
47 #include "nrnb.h"
48
49 #include "gmx_math_x86_sse2_single.h"
50 #include "kernelutil_x86_sse2_single.h"
51
52 /*
53  * Gromacs nonbonded kernel:   nb_kernel_ElecGB_VdwNone_GeomP1P1_VF_sse2_single
54  * Electrostatics interaction: GeneralizedBorn
55  * VdW interaction:            None
56  * Geometry:                   Particle-Particle
57  * Calculate force/pot:        PotentialAndForce
58  */
59 void
60 nb_kernel_ElecGB_VdwNone_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_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     __m128i          gbitab;
93     __m128           vgb,fgb,vgbsum,dvdasum,gbscale,gbtabscale,isaprod,gbqqfactor,gbinvepsdiff,gbeps,dvdatmp;
94     __m128           minushalf = _mm_set1_ps(-0.5);
95     real             *invsqrta,*dvda,*gbtab;
96     __m128i          vfitab;
97     __m128i          ifour       = _mm_set1_epi32(4);
98     __m128           rt,vfeps,vftabscale,Y,F,G,H,Heps,Fp,VV,FF;
99     real             *vftab;
100     __m128           dummy_mask,cutoff_mask;
101     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
102     __m128           one     = _mm_set1_ps(1.0);
103     __m128           two     = _mm_set1_ps(2.0);
104     x                = xx[0];
105     f                = ff[0];
106
107     nri              = nlist->nri;
108     iinr             = nlist->iinr;
109     jindex           = nlist->jindex;
110     jjnr             = nlist->jjnr;
111     shiftidx         = nlist->shift;
112     gid              = nlist->gid;
113     shiftvec         = fr->shift_vec[0];
114     fshift           = fr->fshift[0];
115     facel            = _mm_set1_ps(fr->epsfac);
116     charge           = mdatoms->chargeA;
117
118     invsqrta         = fr->invsqrta;
119     dvda             = fr->dvda;
120     gbtabscale       = _mm_set1_ps(fr->gbtab.scale);
121     gbtab            = fr->gbtab.data;
122     gbinvepsdiff     = _mm_set1_ps((1.0/fr->epsilon_r) - (1.0/fr->gb_epsilon_solvent));
123
124     /* Avoid stupid compiler warnings */
125     jnrA = jnrB = jnrC = jnrD = 0;
126     j_coord_offsetA = 0;
127     j_coord_offsetB = 0;
128     j_coord_offsetC = 0;
129     j_coord_offsetD = 0;
130
131     outeriter        = 0;
132     inneriter        = 0;
133
134     for(iidx=0;iidx<4*DIM;iidx++)
135     {
136         scratch[iidx] = 0.0;
137     }  
138
139     /* Start outer loop over neighborlists */
140     for(iidx=0; iidx<nri; iidx++)
141     {
142         /* Load shift vector for this list */
143         i_shift_offset   = DIM*shiftidx[iidx];
144
145         /* Load limits for loop over neighbors */
146         j_index_start    = jindex[iidx];
147         j_index_end      = jindex[iidx+1];
148
149         /* Get outer coordinate index */
150         inr              = iinr[iidx];
151         i_coord_offset   = DIM*inr;
152
153         /* Load i particle coords and add shift vector */
154         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
155         
156         fix0             = _mm_setzero_ps();
157         fiy0             = _mm_setzero_ps();
158         fiz0             = _mm_setzero_ps();
159
160         /* Load parameters for i particles */
161         iq0              = _mm_mul_ps(facel,_mm_load1_ps(charge+inr+0));
162         isai0            = _mm_load1_ps(invsqrta+inr+0);
163
164         /* Reset potential sums */
165         velecsum         = _mm_setzero_ps();
166         vgbsum           = _mm_setzero_ps();
167         dvdasum          = _mm_setzero_ps();
168
169         /* Start inner kernel loop */
170         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
171         {
172
173             /* Get j neighbor index, and coordinate index */
174             jnrA             = jjnr[jidx];
175             jnrB             = jjnr[jidx+1];
176             jnrC             = jjnr[jidx+2];
177             jnrD             = jjnr[jidx+3];
178             j_coord_offsetA  = DIM*jnrA;
179             j_coord_offsetB  = DIM*jnrB;
180             j_coord_offsetC  = DIM*jnrC;
181             j_coord_offsetD  = DIM*jnrD;
182
183             /* load j atom coordinates */
184             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
185                                               x+j_coord_offsetC,x+j_coord_offsetD,
186                                               &jx0,&jy0,&jz0);
187
188             /* Calculate displacement vector */
189             dx00             = _mm_sub_ps(ix0,jx0);
190             dy00             = _mm_sub_ps(iy0,jy0);
191             dz00             = _mm_sub_ps(iz0,jz0);
192
193             /* Calculate squared distance and things based on it */
194             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
195
196             rinv00           = gmx_mm_invsqrt_ps(rsq00);
197
198             /* Load parameters for j particles */
199             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
200                                                               charge+jnrC+0,charge+jnrD+0);
201             isaj0            = gmx_mm_load_4real_swizzle_ps(invsqrta+jnrA+0,invsqrta+jnrB+0,
202                                                               invsqrta+jnrC+0,invsqrta+jnrD+0);
203
204             /**************************
205              * CALCULATE INTERACTIONS *
206              **************************/
207
208             r00              = _mm_mul_ps(rsq00,rinv00);
209
210             /* Compute parameters for interactions between i and j atoms */
211             qq00             = _mm_mul_ps(iq0,jq0);
212
213             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
214             isaprod          = _mm_mul_ps(isai0,isaj0);
215             gbqqfactor       = _mm_xor_ps(signbit,_mm_mul_ps(qq00,_mm_mul_ps(isaprod,gbinvepsdiff)));
216             gbscale          = _mm_mul_ps(isaprod,gbtabscale);
217
218             /* Calculate generalized born table index - this is a separate table from the normal one,
219              * but we use the same procedure by multiplying r with scale and truncating to integer.
220              */
221             rt               = _mm_mul_ps(r00,gbscale);
222             gbitab           = _mm_cvttps_epi32(rt);
223             gbeps            = _mm_sub_ps(rt,_mm_cvtepi32_ps(gbitab));
224             gbitab           = _mm_slli_epi32(gbitab,2);
225
226             Y                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,0) );
227             F                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,1) );
228             G                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,2) );
229             H                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,3) );
230             _MM_TRANSPOSE4_PS(Y,F,G,H);
231             Heps             = _mm_mul_ps(gbeps,H);
232             Fp               = _mm_add_ps(F,_mm_mul_ps(gbeps,_mm_add_ps(G,Heps)));
233             VV               = _mm_add_ps(Y,_mm_mul_ps(gbeps,Fp));
234             vgb              = _mm_mul_ps(gbqqfactor,VV);
235
236             FF               = _mm_add_ps(Fp,_mm_mul_ps(gbeps,_mm_add_ps(G,_mm_add_ps(Heps,Heps))));
237             fgb              = _mm_mul_ps(gbqqfactor,_mm_mul_ps(FF,gbscale));
238             dvdatmp          = _mm_mul_ps(minushalf,_mm_add_ps(vgb,_mm_mul_ps(fgb,r00)));
239             dvdasum          = _mm_add_ps(dvdasum,dvdatmp);
240             fjptrA           = dvda+jnrA;
241             fjptrB           = dvda+jnrB;
242             fjptrC           = dvda+jnrC;
243             fjptrD           = dvda+jnrD;
244             gmx_mm_increment_4real_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,_mm_mul_ps(dvdatmp,_mm_mul_ps(isaj0,isaj0)));
245             velec            = _mm_mul_ps(qq00,rinv00);
246             felec            = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(velec,rinv00),fgb),rinv00);
247
248             /* Update potential sum for this i atom from the interaction with this j atom. */
249             velecsum         = _mm_add_ps(velecsum,velec);
250             vgbsum           = _mm_add_ps(vgbsum,vgb);
251
252             fscal            = felec;
253
254             /* Calculate temporary vectorial force */
255             tx               = _mm_mul_ps(fscal,dx00);
256             ty               = _mm_mul_ps(fscal,dy00);
257             tz               = _mm_mul_ps(fscal,dz00);
258
259             /* Update vectorial force */
260             fix0             = _mm_add_ps(fix0,tx);
261             fiy0             = _mm_add_ps(fiy0,ty);
262             fiz0             = _mm_add_ps(fiz0,tz);
263
264             fjptrA             = f+j_coord_offsetA;
265             fjptrB             = f+j_coord_offsetB;
266             fjptrC             = f+j_coord_offsetC;
267             fjptrD             = f+j_coord_offsetD;
268             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
269             
270             /* Inner loop uses 58 flops */
271         }
272
273         if(jidx<j_index_end)
274         {
275
276             /* Get j neighbor index, and coordinate index */
277             jnrlistA         = jjnr[jidx];
278             jnrlistB         = jjnr[jidx+1];
279             jnrlistC         = jjnr[jidx+2];
280             jnrlistD         = jjnr[jidx+3];
281             /* Sign of each element will be negative for non-real atoms.
282              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
283              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
284              */
285             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
286             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
287             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
288             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
289             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
290             j_coord_offsetA  = DIM*jnrA;
291             j_coord_offsetB  = DIM*jnrB;
292             j_coord_offsetC  = DIM*jnrC;
293             j_coord_offsetD  = DIM*jnrD;
294
295             /* load j atom coordinates */
296             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
297                                               x+j_coord_offsetC,x+j_coord_offsetD,
298                                               &jx0,&jy0,&jz0);
299
300             /* Calculate displacement vector */
301             dx00             = _mm_sub_ps(ix0,jx0);
302             dy00             = _mm_sub_ps(iy0,jy0);
303             dz00             = _mm_sub_ps(iz0,jz0);
304
305             /* Calculate squared distance and things based on it */
306             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
307
308             rinv00           = gmx_mm_invsqrt_ps(rsq00);
309
310             /* Load parameters for j particles */
311             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
312                                                               charge+jnrC+0,charge+jnrD+0);
313             isaj0            = gmx_mm_load_4real_swizzle_ps(invsqrta+jnrA+0,invsqrta+jnrB+0,
314                                                               invsqrta+jnrC+0,invsqrta+jnrD+0);
315
316             /**************************
317              * CALCULATE INTERACTIONS *
318              **************************/
319
320             r00              = _mm_mul_ps(rsq00,rinv00);
321             r00              = _mm_andnot_ps(dummy_mask,r00);
322
323             /* Compute parameters for interactions between i and j atoms */
324             qq00             = _mm_mul_ps(iq0,jq0);
325
326             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
327             isaprod          = _mm_mul_ps(isai0,isaj0);
328             gbqqfactor       = _mm_xor_ps(signbit,_mm_mul_ps(qq00,_mm_mul_ps(isaprod,gbinvepsdiff)));
329             gbscale          = _mm_mul_ps(isaprod,gbtabscale);
330
331             /* Calculate generalized born table index - this is a separate table from the normal one,
332              * but we use the same procedure by multiplying r with scale and truncating to integer.
333              */
334             rt               = _mm_mul_ps(r00,gbscale);
335             gbitab           = _mm_cvttps_epi32(rt);
336             gbeps            = _mm_sub_ps(rt,_mm_cvtepi32_ps(gbitab));
337             gbitab           = _mm_slli_epi32(gbitab,2);
338
339             Y                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,0) );
340             F                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,1) );
341             G                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,2) );
342             H                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,3) );
343             _MM_TRANSPOSE4_PS(Y,F,G,H);
344             Heps             = _mm_mul_ps(gbeps,H);
345             Fp               = _mm_add_ps(F,_mm_mul_ps(gbeps,_mm_add_ps(G,Heps)));
346             VV               = _mm_add_ps(Y,_mm_mul_ps(gbeps,Fp));
347             vgb              = _mm_mul_ps(gbqqfactor,VV);
348
349             FF               = _mm_add_ps(Fp,_mm_mul_ps(gbeps,_mm_add_ps(G,_mm_add_ps(Heps,Heps))));
350             fgb              = _mm_mul_ps(gbqqfactor,_mm_mul_ps(FF,gbscale));
351             dvdatmp          = _mm_mul_ps(minushalf,_mm_add_ps(vgb,_mm_mul_ps(fgb,r00)));
352             dvdasum          = _mm_add_ps(dvdasum,dvdatmp);
353             /* The pointers to scratch make sure that this code with compilers that take gmx_restrict seriously (e.g. icc 13) really can't screw things up. */
354             fjptrA             = (jnrlistA>=0) ? dvda+jnrA : scratch;
355             fjptrB             = (jnrlistB>=0) ? dvda+jnrB : scratch;
356             fjptrC             = (jnrlistC>=0) ? dvda+jnrC : scratch;
357             fjptrD             = (jnrlistD>=0) ? dvda+jnrD : scratch;
358             gmx_mm_increment_4real_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,_mm_mul_ps(dvdatmp,_mm_mul_ps(isaj0,isaj0)));
359             velec            = _mm_mul_ps(qq00,rinv00);
360             felec            = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(velec,rinv00),fgb),rinv00);
361
362             /* Update potential sum for this i atom from the interaction with this j atom. */
363             velec            = _mm_andnot_ps(dummy_mask,velec);
364             velecsum         = _mm_add_ps(velecsum,velec);
365             vgb              = _mm_andnot_ps(dummy_mask,vgb);
366             vgbsum           = _mm_add_ps(vgbsum,vgb);
367
368             fscal            = felec;
369
370             fscal            = _mm_andnot_ps(dummy_mask,fscal);
371
372             /* Calculate temporary vectorial force */
373             tx               = _mm_mul_ps(fscal,dx00);
374             ty               = _mm_mul_ps(fscal,dy00);
375             tz               = _mm_mul_ps(fscal,dz00);
376
377             /* Update vectorial force */
378             fix0             = _mm_add_ps(fix0,tx);
379             fiy0             = _mm_add_ps(fiy0,ty);
380             fiz0             = _mm_add_ps(fiz0,tz);
381
382             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
383             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
384             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
385             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
386             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
387             
388             /* Inner loop uses 59 flops */
389         }
390
391         /* End of innermost loop */
392
393         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
394                                               f+i_coord_offset,fshift+i_shift_offset);
395
396         ggid                        = gid[iidx];
397         /* Update potential energies */
398         gmx_mm_update_1pot_ps(velecsum,kernel_data->energygrp_elec+ggid);
399         gmx_mm_update_1pot_ps(vgbsum,kernel_data->energygrp_polarization+ggid);
400         dvdasum = _mm_mul_ps(dvdasum, _mm_mul_ps(isai0,isai0));
401         gmx_mm_update_1pot_ps(dvdasum,dvda+inr);
402
403         /* Increment number of inner iterations */
404         inneriter                  += j_index_end - j_index_start;
405
406         /* Outer loop uses 9 flops */
407     }
408
409     /* Increment number of outer iterations */
410     outeriter        += nri;
411
412     /* Update outer/inner flops */
413
414     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VF,outeriter*9 + inneriter*59);
415 }
416 /*
417  * Gromacs nonbonded kernel:   nb_kernel_ElecGB_VdwNone_GeomP1P1_F_sse2_single
418  * Electrostatics interaction: GeneralizedBorn
419  * VdW interaction:            None
420  * Geometry:                   Particle-Particle
421  * Calculate force/pot:        Force
422  */
423 void
424 nb_kernel_ElecGB_VdwNone_GeomP1P1_F_sse2_single
425                     (t_nblist * gmx_restrict                nlist,
426                      rvec * gmx_restrict                    xx,
427                      rvec * gmx_restrict                    ff,
428                      t_forcerec * gmx_restrict              fr,
429                      t_mdatoms * gmx_restrict               mdatoms,
430                      nb_kernel_data_t * gmx_restrict        kernel_data,
431                      t_nrnb * gmx_restrict                  nrnb)
432 {
433     /* Suffixes 0,1,2,3 refer to particle indices for waters in the inner or outer loop, or 
434      * just 0 for non-waters.
435      * Suffixes A,B,C,D refer to j loop unrolling done with SSE, e.g. for the four different
436      * jnr indices corresponding to data put in the four positions in the SIMD register.
437      */
438     int              i_shift_offset,i_coord_offset,outeriter,inneriter;
439     int              j_index_start,j_index_end,jidx,nri,inr,ggid,iidx;
440     int              jnrA,jnrB,jnrC,jnrD;
441     int              jnrlistA,jnrlistB,jnrlistC,jnrlistD;
442     int              j_coord_offsetA,j_coord_offsetB,j_coord_offsetC,j_coord_offsetD;
443     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
444     real             rcutoff_scalar;
445     real             *shiftvec,*fshift,*x,*f;
446     real             *fjptrA,*fjptrB,*fjptrC,*fjptrD;
447     real             scratch[4*DIM];
448     __m128           tx,ty,tz,fscal,rcutoff,rcutoff2,jidxall;
449     int              vdwioffset0;
450     __m128           ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
451     int              vdwjidx0A,vdwjidx0B,vdwjidx0C,vdwjidx0D;
452     __m128           jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
453     __m128           dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00;
454     __m128           velec,felec,velecsum,facel,crf,krf,krf2;
455     real             *charge;
456     __m128i          gbitab;
457     __m128           vgb,fgb,vgbsum,dvdasum,gbscale,gbtabscale,isaprod,gbqqfactor,gbinvepsdiff,gbeps,dvdatmp;
458     __m128           minushalf = _mm_set1_ps(-0.5);
459     real             *invsqrta,*dvda,*gbtab;
460     __m128i          vfitab;
461     __m128i          ifour       = _mm_set1_epi32(4);
462     __m128           rt,vfeps,vftabscale,Y,F,G,H,Heps,Fp,VV,FF;
463     real             *vftab;
464     __m128           dummy_mask,cutoff_mask;
465     __m128           signbit = _mm_castsi128_ps( _mm_set1_epi32(0x80000000) );
466     __m128           one     = _mm_set1_ps(1.0);
467     __m128           two     = _mm_set1_ps(2.0);
468     x                = xx[0];
469     f                = ff[0];
470
471     nri              = nlist->nri;
472     iinr             = nlist->iinr;
473     jindex           = nlist->jindex;
474     jjnr             = nlist->jjnr;
475     shiftidx         = nlist->shift;
476     gid              = nlist->gid;
477     shiftvec         = fr->shift_vec[0];
478     fshift           = fr->fshift[0];
479     facel            = _mm_set1_ps(fr->epsfac);
480     charge           = mdatoms->chargeA;
481
482     invsqrta         = fr->invsqrta;
483     dvda             = fr->dvda;
484     gbtabscale       = _mm_set1_ps(fr->gbtab.scale);
485     gbtab            = fr->gbtab.data;
486     gbinvepsdiff     = _mm_set1_ps((1.0/fr->epsilon_r) - (1.0/fr->gb_epsilon_solvent));
487
488     /* Avoid stupid compiler warnings */
489     jnrA = jnrB = jnrC = jnrD = 0;
490     j_coord_offsetA = 0;
491     j_coord_offsetB = 0;
492     j_coord_offsetC = 0;
493     j_coord_offsetD = 0;
494
495     outeriter        = 0;
496     inneriter        = 0;
497
498     for(iidx=0;iidx<4*DIM;iidx++)
499     {
500         scratch[iidx] = 0.0;
501     }  
502
503     /* Start outer loop over neighborlists */
504     for(iidx=0; iidx<nri; iidx++)
505     {
506         /* Load shift vector for this list */
507         i_shift_offset   = DIM*shiftidx[iidx];
508
509         /* Load limits for loop over neighbors */
510         j_index_start    = jindex[iidx];
511         j_index_end      = jindex[iidx+1];
512
513         /* Get outer coordinate index */
514         inr              = iinr[iidx];
515         i_coord_offset   = DIM*inr;
516
517         /* Load i particle coords and add shift vector */
518         gmx_mm_load_shift_and_1rvec_broadcast_ps(shiftvec+i_shift_offset,x+i_coord_offset,&ix0,&iy0,&iz0);
519         
520         fix0             = _mm_setzero_ps();
521         fiy0             = _mm_setzero_ps();
522         fiz0             = _mm_setzero_ps();
523
524         /* Load parameters for i particles */
525         iq0              = _mm_mul_ps(facel,_mm_load1_ps(charge+inr+0));
526         isai0            = _mm_load1_ps(invsqrta+inr+0);
527
528         dvdasum          = _mm_setzero_ps();
529
530         /* Start inner kernel loop */
531         for(jidx=j_index_start; jidx<j_index_end && jjnr[jidx+3]>=0; jidx+=4)
532         {
533
534             /* Get j neighbor index, and coordinate index */
535             jnrA             = jjnr[jidx];
536             jnrB             = jjnr[jidx+1];
537             jnrC             = jjnr[jidx+2];
538             jnrD             = jjnr[jidx+3];
539             j_coord_offsetA  = DIM*jnrA;
540             j_coord_offsetB  = DIM*jnrB;
541             j_coord_offsetC  = DIM*jnrC;
542             j_coord_offsetD  = DIM*jnrD;
543
544             /* load j atom coordinates */
545             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
546                                               x+j_coord_offsetC,x+j_coord_offsetD,
547                                               &jx0,&jy0,&jz0);
548
549             /* Calculate displacement vector */
550             dx00             = _mm_sub_ps(ix0,jx0);
551             dy00             = _mm_sub_ps(iy0,jy0);
552             dz00             = _mm_sub_ps(iz0,jz0);
553
554             /* Calculate squared distance and things based on it */
555             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
556
557             rinv00           = gmx_mm_invsqrt_ps(rsq00);
558
559             /* Load parameters for j particles */
560             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
561                                                               charge+jnrC+0,charge+jnrD+0);
562             isaj0            = gmx_mm_load_4real_swizzle_ps(invsqrta+jnrA+0,invsqrta+jnrB+0,
563                                                               invsqrta+jnrC+0,invsqrta+jnrD+0);
564
565             /**************************
566              * CALCULATE INTERACTIONS *
567              **************************/
568
569             r00              = _mm_mul_ps(rsq00,rinv00);
570
571             /* Compute parameters for interactions between i and j atoms */
572             qq00             = _mm_mul_ps(iq0,jq0);
573
574             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
575             isaprod          = _mm_mul_ps(isai0,isaj0);
576             gbqqfactor       = _mm_xor_ps(signbit,_mm_mul_ps(qq00,_mm_mul_ps(isaprod,gbinvepsdiff)));
577             gbscale          = _mm_mul_ps(isaprod,gbtabscale);
578
579             /* Calculate generalized born table index - this is a separate table from the normal one,
580              * but we use the same procedure by multiplying r with scale and truncating to integer.
581              */
582             rt               = _mm_mul_ps(r00,gbscale);
583             gbitab           = _mm_cvttps_epi32(rt);
584             gbeps            = _mm_sub_ps(rt,_mm_cvtepi32_ps(gbitab));
585             gbitab           = _mm_slli_epi32(gbitab,2);
586
587             Y                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,0) );
588             F                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,1) );
589             G                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,2) );
590             H                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,3) );
591             _MM_TRANSPOSE4_PS(Y,F,G,H);
592             Heps             = _mm_mul_ps(gbeps,H);
593             Fp               = _mm_add_ps(F,_mm_mul_ps(gbeps,_mm_add_ps(G,Heps)));
594             VV               = _mm_add_ps(Y,_mm_mul_ps(gbeps,Fp));
595             vgb              = _mm_mul_ps(gbqqfactor,VV);
596
597             FF               = _mm_add_ps(Fp,_mm_mul_ps(gbeps,_mm_add_ps(G,_mm_add_ps(Heps,Heps))));
598             fgb              = _mm_mul_ps(gbqqfactor,_mm_mul_ps(FF,gbscale));
599             dvdatmp          = _mm_mul_ps(minushalf,_mm_add_ps(vgb,_mm_mul_ps(fgb,r00)));
600             dvdasum          = _mm_add_ps(dvdasum,dvdatmp);
601             fjptrA           = dvda+jnrA;
602             fjptrB           = dvda+jnrB;
603             fjptrC           = dvda+jnrC;
604             fjptrD           = dvda+jnrD;
605             gmx_mm_increment_4real_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,_mm_mul_ps(dvdatmp,_mm_mul_ps(isaj0,isaj0)));
606             velec            = _mm_mul_ps(qq00,rinv00);
607             felec            = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(velec,rinv00),fgb),rinv00);
608
609             fscal            = felec;
610
611             /* Calculate temporary vectorial force */
612             tx               = _mm_mul_ps(fscal,dx00);
613             ty               = _mm_mul_ps(fscal,dy00);
614             tz               = _mm_mul_ps(fscal,dz00);
615
616             /* Update vectorial force */
617             fix0             = _mm_add_ps(fix0,tx);
618             fiy0             = _mm_add_ps(fiy0,ty);
619             fiz0             = _mm_add_ps(fiz0,tz);
620
621             fjptrA             = f+j_coord_offsetA;
622             fjptrB             = f+j_coord_offsetB;
623             fjptrC             = f+j_coord_offsetC;
624             fjptrD             = f+j_coord_offsetD;
625             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
626             
627             /* Inner loop uses 56 flops */
628         }
629
630         if(jidx<j_index_end)
631         {
632
633             /* Get j neighbor index, and coordinate index */
634             jnrlistA         = jjnr[jidx];
635             jnrlistB         = jjnr[jidx+1];
636             jnrlistC         = jjnr[jidx+2];
637             jnrlistD         = jjnr[jidx+3];
638             /* Sign of each element will be negative for non-real atoms.
639              * This mask will be 0xFFFFFFFF for dummy entries and 0x0 for real ones,
640              * so use it as val = _mm_andnot_ps(mask,val) to clear dummy entries.
641              */
642             dummy_mask = gmx_mm_castsi128_ps(_mm_cmplt_epi32(_mm_loadu_si128((const __m128i *)(jjnr+jidx)),_mm_setzero_si128()));
643             jnrA       = (jnrlistA>=0) ? jnrlistA : 0;
644             jnrB       = (jnrlistB>=0) ? jnrlistB : 0;
645             jnrC       = (jnrlistC>=0) ? jnrlistC : 0;
646             jnrD       = (jnrlistD>=0) ? jnrlistD : 0;
647             j_coord_offsetA  = DIM*jnrA;
648             j_coord_offsetB  = DIM*jnrB;
649             j_coord_offsetC  = DIM*jnrC;
650             j_coord_offsetD  = DIM*jnrD;
651
652             /* load j atom coordinates */
653             gmx_mm_load_1rvec_4ptr_swizzle_ps(x+j_coord_offsetA,x+j_coord_offsetB,
654                                               x+j_coord_offsetC,x+j_coord_offsetD,
655                                               &jx0,&jy0,&jz0);
656
657             /* Calculate displacement vector */
658             dx00             = _mm_sub_ps(ix0,jx0);
659             dy00             = _mm_sub_ps(iy0,jy0);
660             dz00             = _mm_sub_ps(iz0,jz0);
661
662             /* Calculate squared distance and things based on it */
663             rsq00            = gmx_mm_calc_rsq_ps(dx00,dy00,dz00);
664
665             rinv00           = gmx_mm_invsqrt_ps(rsq00);
666
667             /* Load parameters for j particles */
668             jq0              = gmx_mm_load_4real_swizzle_ps(charge+jnrA+0,charge+jnrB+0,
669                                                               charge+jnrC+0,charge+jnrD+0);
670             isaj0            = gmx_mm_load_4real_swizzle_ps(invsqrta+jnrA+0,invsqrta+jnrB+0,
671                                                               invsqrta+jnrC+0,invsqrta+jnrD+0);
672
673             /**************************
674              * CALCULATE INTERACTIONS *
675              **************************/
676
677             r00              = _mm_mul_ps(rsq00,rinv00);
678             r00              = _mm_andnot_ps(dummy_mask,r00);
679
680             /* Compute parameters for interactions between i and j atoms */
681             qq00             = _mm_mul_ps(iq0,jq0);
682
683             /* GENERALIZED BORN AND COULOMB ELECTROSTATICS */
684             isaprod          = _mm_mul_ps(isai0,isaj0);
685             gbqqfactor       = _mm_xor_ps(signbit,_mm_mul_ps(qq00,_mm_mul_ps(isaprod,gbinvepsdiff)));
686             gbscale          = _mm_mul_ps(isaprod,gbtabscale);
687
688             /* Calculate generalized born table index - this is a separate table from the normal one,
689              * but we use the same procedure by multiplying r with scale and truncating to integer.
690              */
691             rt               = _mm_mul_ps(r00,gbscale);
692             gbitab           = _mm_cvttps_epi32(rt);
693             gbeps            = _mm_sub_ps(rt,_mm_cvtepi32_ps(gbitab));
694             gbitab           = _mm_slli_epi32(gbitab,2);
695
696             Y                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,0) );
697             F                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,1) );
698             G                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,2) );
699             H                = _mm_load_ps( gbtab + gmx_mm_extract_epi32(gbitab,3) );
700             _MM_TRANSPOSE4_PS(Y,F,G,H);
701             Heps             = _mm_mul_ps(gbeps,H);
702             Fp               = _mm_add_ps(F,_mm_mul_ps(gbeps,_mm_add_ps(G,Heps)));
703             VV               = _mm_add_ps(Y,_mm_mul_ps(gbeps,Fp));
704             vgb              = _mm_mul_ps(gbqqfactor,VV);
705
706             FF               = _mm_add_ps(Fp,_mm_mul_ps(gbeps,_mm_add_ps(G,_mm_add_ps(Heps,Heps))));
707             fgb              = _mm_mul_ps(gbqqfactor,_mm_mul_ps(FF,gbscale));
708             dvdatmp          = _mm_mul_ps(minushalf,_mm_add_ps(vgb,_mm_mul_ps(fgb,r00)));
709             dvdasum          = _mm_add_ps(dvdasum,dvdatmp);
710             /* The pointers to scratch make sure that this code with compilers that take gmx_restrict seriously (e.g. icc 13) really can't screw things up. */
711             fjptrA             = (jnrlistA>=0) ? dvda+jnrA : scratch;
712             fjptrB             = (jnrlistB>=0) ? dvda+jnrB : scratch;
713             fjptrC             = (jnrlistC>=0) ? dvda+jnrC : scratch;
714             fjptrD             = (jnrlistD>=0) ? dvda+jnrD : scratch;
715             gmx_mm_increment_4real_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,_mm_mul_ps(dvdatmp,_mm_mul_ps(isaj0,isaj0)));
716             velec            = _mm_mul_ps(qq00,rinv00);
717             felec            = _mm_mul_ps(_mm_sub_ps(_mm_mul_ps(velec,rinv00),fgb),rinv00);
718
719             fscal            = felec;
720
721             fscal            = _mm_andnot_ps(dummy_mask,fscal);
722
723             /* Calculate temporary vectorial force */
724             tx               = _mm_mul_ps(fscal,dx00);
725             ty               = _mm_mul_ps(fscal,dy00);
726             tz               = _mm_mul_ps(fscal,dz00);
727
728             /* Update vectorial force */
729             fix0             = _mm_add_ps(fix0,tx);
730             fiy0             = _mm_add_ps(fiy0,ty);
731             fiz0             = _mm_add_ps(fiz0,tz);
732
733             fjptrA             = (jnrlistA>=0) ? f+j_coord_offsetA : scratch;
734             fjptrB             = (jnrlistB>=0) ? f+j_coord_offsetB : scratch;
735             fjptrC             = (jnrlistC>=0) ? f+j_coord_offsetC : scratch;
736             fjptrD             = (jnrlistD>=0) ? f+j_coord_offsetD : scratch;
737             gmx_mm_decrement_1rvec_4ptr_swizzle_ps(fjptrA,fjptrB,fjptrC,fjptrD,tx,ty,tz);
738             
739             /* Inner loop uses 57 flops */
740         }
741
742         /* End of innermost loop */
743
744         gmx_mm_update_iforce_1atom_swizzle_ps(fix0,fiy0,fiz0,
745                                               f+i_coord_offset,fshift+i_shift_offset);
746
747         dvdasum = _mm_mul_ps(dvdasum, _mm_mul_ps(isai0,isai0));
748         gmx_mm_update_1pot_ps(dvdasum,dvda+inr);
749
750         /* Increment number of inner iterations */
751         inneriter                  += j_index_end - j_index_start;
752
753         /* Outer loop uses 7 flops */
754     }
755
756     /* Increment number of outer iterations */
757     outeriter        += nri;
758
759     /* Update outer/inner flops */
760
761     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_F,outeriter*7 + inneriter*57);
762 }