Remove all unnecessary HAVE_CONFIG_H
[alexxy/gromacs.git] / src / gromacs / gmxlib / nonbonded / nb_kernel_c / nb_kernel_ElecEwSw_VdwBhamSw_GeomW4W4_c.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 c 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 /*
48  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSw_VdwBhamSw_GeomW4W4_VF_c
49  * Electrostatics interaction: Ewald
50  * VdW interaction:            Buckingham
51  * Geometry:                   Water4-Water4
52  * Calculate force/pot:        PotentialAndForce
53  */
54 void
55 nb_kernel_ElecEwSw_VdwBhamSw_GeomW4W4_VF_c
56                     (t_nblist                    * gmx_restrict       nlist,
57                      rvec                        * gmx_restrict          xx,
58                      rvec                        * gmx_restrict          ff,
59                      t_forcerec                  * gmx_restrict          fr,
60                      t_mdatoms                   * gmx_restrict     mdatoms,
61                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
62                      t_nrnb                      * gmx_restrict        nrnb)
63 {
64     int              i_shift_offset,i_coord_offset,j_coord_offset;
65     int              j_index_start,j_index_end;
66     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
67     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
68     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
69     real             *shiftvec,*fshift,*x,*f;
70     int              vdwioffset0;
71     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
72     int              vdwioffset1;
73     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
74     int              vdwioffset2;
75     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
76     int              vdwioffset3;
77     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
78     int              vdwjidx0;
79     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
80     int              vdwjidx1;
81     real             jx1,jy1,jz1,fjx1,fjy1,fjz1,jq1,isaj1;
82     int              vdwjidx2;
83     real             jx2,jy2,jz2,fjx2,fjy2,fjz2,jq2,isaj2;
84     int              vdwjidx3;
85     real             jx3,jy3,jz3,fjx3,fjy3,fjz3,jq3,isaj3;
86     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
87     real             dx11,dy11,dz11,rsq11,rinv11,rinvsq11,r11,qq11,c6_11,c12_11,cexp1_11,cexp2_11;
88     real             dx12,dy12,dz12,rsq12,rinv12,rinvsq12,r12,qq12,c6_12,c12_12,cexp1_12,cexp2_12;
89     real             dx13,dy13,dz13,rsq13,rinv13,rinvsq13,r13,qq13,c6_13,c12_13,cexp1_13,cexp2_13;
90     real             dx21,dy21,dz21,rsq21,rinv21,rinvsq21,r21,qq21,c6_21,c12_21,cexp1_21,cexp2_21;
91     real             dx22,dy22,dz22,rsq22,rinv22,rinvsq22,r22,qq22,c6_22,c12_22,cexp1_22,cexp2_22;
92     real             dx23,dy23,dz23,rsq23,rinv23,rinvsq23,r23,qq23,c6_23,c12_23,cexp1_23,cexp2_23;
93     real             dx31,dy31,dz31,rsq31,rinv31,rinvsq31,r31,qq31,c6_31,c12_31,cexp1_31,cexp2_31;
94     real             dx32,dy32,dz32,rsq32,rinv32,rinvsq32,r32,qq32,c6_32,c12_32,cexp1_32,cexp2_32;
95     real             dx33,dy33,dz33,rsq33,rinv33,rinvsq33,r33,qq33,c6_33,c12_33,cexp1_33,cexp2_33;
96     real             velec,felec,velecsum,facel,crf,krf,krf2;
97     real             *charge;
98     int              nvdwtype;
99     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
100     int              *vdwtype;
101     real             *vdwparam;
102     int              ewitab;
103     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
104     real             *ewtab;
105     real             rswitch,swV3,swV4,swV5,swF2,swF3,swF4,d,d2,sw,dsw;
106
107     x                = xx[0];
108     f                = ff[0];
109
110     nri              = nlist->nri;
111     iinr             = nlist->iinr;
112     jindex           = nlist->jindex;
113     jjnr             = nlist->jjnr;
114     shiftidx         = nlist->shift;
115     gid              = nlist->gid;
116     shiftvec         = fr->shift_vec[0];
117     fshift           = fr->fshift[0];
118     facel            = fr->epsfac;
119     charge           = mdatoms->chargeA;
120     nvdwtype         = fr->ntype;
121     vdwparam         = fr->nbfp;
122     vdwtype          = mdatoms->typeA;
123
124     sh_ewald         = fr->ic->sh_ewald;
125     ewtab            = fr->ic->tabq_coul_FDV0;
126     ewtabscale       = fr->ic->tabq_scale;
127     ewtabhalfspace   = 0.5/ewtabscale;
128
129     /* Setup water-specific parameters */
130     inr              = nlist->iinr[0];
131     iq1              = facel*charge[inr+1];
132     iq2              = facel*charge[inr+2];
133     iq3              = facel*charge[inr+3];
134     vdwioffset0      = 3*nvdwtype*vdwtype[inr+0];
135
136     jq1              = charge[inr+1];
137     jq2              = charge[inr+2];
138     jq3              = charge[inr+3];
139     vdwjidx0         = 3*vdwtype[inr+0];
140     c6_00            = vdwparam[vdwioffset0+vdwjidx0];
141     cexp1_00         = vdwparam[vdwioffset0+vdwjidx0+1];
142     cexp2_00         = vdwparam[vdwioffset0+vdwjidx0+2];
143     qq11             = iq1*jq1;
144     qq12             = iq1*jq2;
145     qq13             = iq1*jq3;
146     qq21             = iq2*jq1;
147     qq22             = iq2*jq2;
148     qq23             = iq2*jq3;
149     qq31             = iq3*jq1;
150     qq32             = iq3*jq2;
151     qq33             = iq3*jq3;
152
153     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
154     rcutoff          = fr->rcoulomb;
155     rcutoff2         = rcutoff*rcutoff;
156
157     rswitch          = fr->rcoulomb_switch;
158     /* Setup switch parameters */
159     d                = rcutoff-rswitch;
160     swV3             = -10.0/(d*d*d);
161     swV4             =  15.0/(d*d*d*d);
162     swV5             =  -6.0/(d*d*d*d*d);
163     swF2             = -30.0/(d*d*d);
164     swF3             =  60.0/(d*d*d*d);
165     swF4             = -30.0/(d*d*d*d*d);
166
167     outeriter        = 0;
168     inneriter        = 0;
169
170     /* Start outer loop over neighborlists */
171     for(iidx=0; iidx<nri; iidx++)
172     {
173         /* Load shift vector for this list */
174         i_shift_offset   = DIM*shiftidx[iidx];
175         shX              = shiftvec[i_shift_offset+XX];
176         shY              = shiftvec[i_shift_offset+YY];
177         shZ              = shiftvec[i_shift_offset+ZZ];
178
179         /* Load limits for loop over neighbors */
180         j_index_start    = jindex[iidx];
181         j_index_end      = jindex[iidx+1];
182
183         /* Get outer coordinate index */
184         inr              = iinr[iidx];
185         i_coord_offset   = DIM*inr;
186
187         /* Load i particle coords and add shift vector */
188         ix0              = shX + x[i_coord_offset+DIM*0+XX];
189         iy0              = shY + x[i_coord_offset+DIM*0+YY];
190         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
191         ix1              = shX + x[i_coord_offset+DIM*1+XX];
192         iy1              = shY + x[i_coord_offset+DIM*1+YY];
193         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
194         ix2              = shX + x[i_coord_offset+DIM*2+XX];
195         iy2              = shY + x[i_coord_offset+DIM*2+YY];
196         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
197         ix3              = shX + x[i_coord_offset+DIM*3+XX];
198         iy3              = shY + x[i_coord_offset+DIM*3+YY];
199         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
200
201         fix0             = 0.0;
202         fiy0             = 0.0;
203         fiz0             = 0.0;
204         fix1             = 0.0;
205         fiy1             = 0.0;
206         fiz1             = 0.0;
207         fix2             = 0.0;
208         fiy2             = 0.0;
209         fiz2             = 0.0;
210         fix3             = 0.0;
211         fiy3             = 0.0;
212         fiz3             = 0.0;
213
214         /* Reset potential sums */
215         velecsum         = 0.0;
216         vvdwsum          = 0.0;
217
218         /* Start inner kernel loop */
219         for(jidx=j_index_start; jidx<j_index_end; jidx++)
220         {
221             /* Get j neighbor index, and coordinate index */
222             jnr              = jjnr[jidx];
223             j_coord_offset   = DIM*jnr;
224
225             /* load j atom coordinates */
226             jx0              = x[j_coord_offset+DIM*0+XX];
227             jy0              = x[j_coord_offset+DIM*0+YY];
228             jz0              = x[j_coord_offset+DIM*0+ZZ];
229             jx1              = x[j_coord_offset+DIM*1+XX];
230             jy1              = x[j_coord_offset+DIM*1+YY];
231             jz1              = x[j_coord_offset+DIM*1+ZZ];
232             jx2              = x[j_coord_offset+DIM*2+XX];
233             jy2              = x[j_coord_offset+DIM*2+YY];
234             jz2              = x[j_coord_offset+DIM*2+ZZ];
235             jx3              = x[j_coord_offset+DIM*3+XX];
236             jy3              = x[j_coord_offset+DIM*3+YY];
237             jz3              = x[j_coord_offset+DIM*3+ZZ];
238
239             /* Calculate displacement vector */
240             dx00             = ix0 - jx0;
241             dy00             = iy0 - jy0;
242             dz00             = iz0 - jz0;
243             dx11             = ix1 - jx1;
244             dy11             = iy1 - jy1;
245             dz11             = iz1 - jz1;
246             dx12             = ix1 - jx2;
247             dy12             = iy1 - jy2;
248             dz12             = iz1 - jz2;
249             dx13             = ix1 - jx3;
250             dy13             = iy1 - jy3;
251             dz13             = iz1 - jz3;
252             dx21             = ix2 - jx1;
253             dy21             = iy2 - jy1;
254             dz21             = iz2 - jz1;
255             dx22             = ix2 - jx2;
256             dy22             = iy2 - jy2;
257             dz22             = iz2 - jz2;
258             dx23             = ix2 - jx3;
259             dy23             = iy2 - jy3;
260             dz23             = iz2 - jz3;
261             dx31             = ix3 - jx1;
262             dy31             = iy3 - jy1;
263             dz31             = iz3 - jz1;
264             dx32             = ix3 - jx2;
265             dy32             = iy3 - jy2;
266             dz32             = iz3 - jz2;
267             dx33             = ix3 - jx3;
268             dy33             = iy3 - jy3;
269             dz33             = iz3 - jz3;
270
271             /* Calculate squared distance and things based on it */
272             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
273             rsq11            = dx11*dx11+dy11*dy11+dz11*dz11;
274             rsq12            = dx12*dx12+dy12*dy12+dz12*dz12;
275             rsq13            = dx13*dx13+dy13*dy13+dz13*dz13;
276             rsq21            = dx21*dx21+dy21*dy21+dz21*dz21;
277             rsq22            = dx22*dx22+dy22*dy22+dz22*dz22;
278             rsq23            = dx23*dx23+dy23*dy23+dz23*dz23;
279             rsq31            = dx31*dx31+dy31*dy31+dz31*dz31;
280             rsq32            = dx32*dx32+dy32*dy32+dz32*dz32;
281             rsq33            = dx33*dx33+dy33*dy33+dz33*dz33;
282
283             rinv00           = gmx_invsqrt(rsq00);
284             rinv11           = gmx_invsqrt(rsq11);
285             rinv12           = gmx_invsqrt(rsq12);
286             rinv13           = gmx_invsqrt(rsq13);
287             rinv21           = gmx_invsqrt(rsq21);
288             rinv22           = gmx_invsqrt(rsq22);
289             rinv23           = gmx_invsqrt(rsq23);
290             rinv31           = gmx_invsqrt(rsq31);
291             rinv32           = gmx_invsqrt(rsq32);
292             rinv33           = gmx_invsqrt(rsq33);
293
294             rinvsq00         = rinv00*rinv00;
295             rinvsq11         = rinv11*rinv11;
296             rinvsq12         = rinv12*rinv12;
297             rinvsq13         = rinv13*rinv13;
298             rinvsq21         = rinv21*rinv21;
299             rinvsq22         = rinv22*rinv22;
300             rinvsq23         = rinv23*rinv23;
301             rinvsq31         = rinv31*rinv31;
302             rinvsq32         = rinv32*rinv32;
303             rinvsq33         = rinv33*rinv33;
304
305             /**************************
306              * CALCULATE INTERACTIONS *
307              **************************/
308
309             if (rsq00<rcutoff2)
310             {
311
312             r00              = rsq00*rinv00;
313
314             /* BUCKINGHAM DISPERSION/REPULSION */
315             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
316             vvdw6            = c6_00*rinvsix;
317             br               = cexp2_00*r00;
318             vvdwexp          = cexp1_00*exp(-br);
319             vvdw             = vvdwexp - vvdw6*(1.0/6.0);
320             fvdw             = (br*vvdwexp-vvdw6)*rinvsq00;
321
322             d                = r00-rswitch;
323             d                = (d>0.0) ? d : 0.0;
324             d2               = d*d;
325             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
326
327             dsw              = d2*(swF2+d*(swF3+d*swF4));
328
329             /* Evaluate switch function */
330             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
331             fvdw             = fvdw*sw - rinv00*vvdw*dsw;
332             vvdw            *= sw;
333
334             /* Update potential sums from outer loop */
335             vvdwsum         += vvdw;
336
337             fscal            = fvdw;
338
339             /* Calculate temporary vectorial force */
340             tx               = fscal*dx00;
341             ty               = fscal*dy00;
342             tz               = fscal*dz00;
343
344             /* Update vectorial force */
345             fix0            += tx;
346             fiy0            += ty;
347             fiz0            += tz;
348             f[j_coord_offset+DIM*0+XX] -= tx;
349             f[j_coord_offset+DIM*0+YY] -= ty;
350             f[j_coord_offset+DIM*0+ZZ] -= tz;
351
352             }
353
354             /**************************
355              * CALCULATE INTERACTIONS *
356              **************************/
357
358             if (rsq11<rcutoff2)
359             {
360
361             r11              = rsq11*rinv11;
362
363             /* EWALD ELECTROSTATICS */
364
365             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
366             ewrt             = r11*ewtabscale;
367             ewitab           = ewrt;
368             eweps            = ewrt-ewitab;
369             ewitab           = 4*ewitab;
370             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
371             velec            = qq11*(rinv11-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
372             felec            = qq11*rinv11*(rinvsq11-felec);
373
374             d                = r11-rswitch;
375             d                = (d>0.0) ? d : 0.0;
376             d2               = d*d;
377             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
378
379             dsw              = d2*(swF2+d*(swF3+d*swF4));
380
381             /* Evaluate switch function */
382             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
383             felec            = felec*sw - rinv11*velec*dsw;
384             velec           *= sw;
385
386             /* Update potential sums from outer loop */
387             velecsum        += velec;
388
389             fscal            = felec;
390
391             /* Calculate temporary vectorial force */
392             tx               = fscal*dx11;
393             ty               = fscal*dy11;
394             tz               = fscal*dz11;
395
396             /* Update vectorial force */
397             fix1            += tx;
398             fiy1            += ty;
399             fiz1            += tz;
400             f[j_coord_offset+DIM*1+XX] -= tx;
401             f[j_coord_offset+DIM*1+YY] -= ty;
402             f[j_coord_offset+DIM*1+ZZ] -= tz;
403
404             }
405
406             /**************************
407              * CALCULATE INTERACTIONS *
408              **************************/
409
410             if (rsq12<rcutoff2)
411             {
412
413             r12              = rsq12*rinv12;
414
415             /* EWALD ELECTROSTATICS */
416
417             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
418             ewrt             = r12*ewtabscale;
419             ewitab           = ewrt;
420             eweps            = ewrt-ewitab;
421             ewitab           = 4*ewitab;
422             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
423             velec            = qq12*(rinv12-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
424             felec            = qq12*rinv12*(rinvsq12-felec);
425
426             d                = r12-rswitch;
427             d                = (d>0.0) ? d : 0.0;
428             d2               = d*d;
429             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
430
431             dsw              = d2*(swF2+d*(swF3+d*swF4));
432
433             /* Evaluate switch function */
434             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
435             felec            = felec*sw - rinv12*velec*dsw;
436             velec           *= sw;
437
438             /* Update potential sums from outer loop */
439             velecsum        += velec;
440
441             fscal            = felec;
442
443             /* Calculate temporary vectorial force */
444             tx               = fscal*dx12;
445             ty               = fscal*dy12;
446             tz               = fscal*dz12;
447
448             /* Update vectorial force */
449             fix1            += tx;
450             fiy1            += ty;
451             fiz1            += tz;
452             f[j_coord_offset+DIM*2+XX] -= tx;
453             f[j_coord_offset+DIM*2+YY] -= ty;
454             f[j_coord_offset+DIM*2+ZZ] -= tz;
455
456             }
457
458             /**************************
459              * CALCULATE INTERACTIONS *
460              **************************/
461
462             if (rsq13<rcutoff2)
463             {
464
465             r13              = rsq13*rinv13;
466
467             /* EWALD ELECTROSTATICS */
468
469             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
470             ewrt             = r13*ewtabscale;
471             ewitab           = ewrt;
472             eweps            = ewrt-ewitab;
473             ewitab           = 4*ewitab;
474             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
475             velec            = qq13*(rinv13-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
476             felec            = qq13*rinv13*(rinvsq13-felec);
477
478             d                = r13-rswitch;
479             d                = (d>0.0) ? d : 0.0;
480             d2               = d*d;
481             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
482
483             dsw              = d2*(swF2+d*(swF3+d*swF4));
484
485             /* Evaluate switch function */
486             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
487             felec            = felec*sw - rinv13*velec*dsw;
488             velec           *= sw;
489
490             /* Update potential sums from outer loop */
491             velecsum        += velec;
492
493             fscal            = felec;
494
495             /* Calculate temporary vectorial force */
496             tx               = fscal*dx13;
497             ty               = fscal*dy13;
498             tz               = fscal*dz13;
499
500             /* Update vectorial force */
501             fix1            += tx;
502             fiy1            += ty;
503             fiz1            += tz;
504             f[j_coord_offset+DIM*3+XX] -= tx;
505             f[j_coord_offset+DIM*3+YY] -= ty;
506             f[j_coord_offset+DIM*3+ZZ] -= tz;
507
508             }
509
510             /**************************
511              * CALCULATE INTERACTIONS *
512              **************************/
513
514             if (rsq21<rcutoff2)
515             {
516
517             r21              = rsq21*rinv21;
518
519             /* EWALD ELECTROSTATICS */
520
521             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
522             ewrt             = r21*ewtabscale;
523             ewitab           = ewrt;
524             eweps            = ewrt-ewitab;
525             ewitab           = 4*ewitab;
526             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
527             velec            = qq21*(rinv21-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
528             felec            = qq21*rinv21*(rinvsq21-felec);
529
530             d                = r21-rswitch;
531             d                = (d>0.0) ? d : 0.0;
532             d2               = d*d;
533             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
534
535             dsw              = d2*(swF2+d*(swF3+d*swF4));
536
537             /* Evaluate switch function */
538             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
539             felec            = felec*sw - rinv21*velec*dsw;
540             velec           *= sw;
541
542             /* Update potential sums from outer loop */
543             velecsum        += velec;
544
545             fscal            = felec;
546
547             /* Calculate temporary vectorial force */
548             tx               = fscal*dx21;
549             ty               = fscal*dy21;
550             tz               = fscal*dz21;
551
552             /* Update vectorial force */
553             fix2            += tx;
554             fiy2            += ty;
555             fiz2            += tz;
556             f[j_coord_offset+DIM*1+XX] -= tx;
557             f[j_coord_offset+DIM*1+YY] -= ty;
558             f[j_coord_offset+DIM*1+ZZ] -= tz;
559
560             }
561
562             /**************************
563              * CALCULATE INTERACTIONS *
564              **************************/
565
566             if (rsq22<rcutoff2)
567             {
568
569             r22              = rsq22*rinv22;
570
571             /* EWALD ELECTROSTATICS */
572
573             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
574             ewrt             = r22*ewtabscale;
575             ewitab           = ewrt;
576             eweps            = ewrt-ewitab;
577             ewitab           = 4*ewitab;
578             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
579             velec            = qq22*(rinv22-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
580             felec            = qq22*rinv22*(rinvsq22-felec);
581
582             d                = r22-rswitch;
583             d                = (d>0.0) ? d : 0.0;
584             d2               = d*d;
585             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
586
587             dsw              = d2*(swF2+d*(swF3+d*swF4));
588
589             /* Evaluate switch function */
590             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
591             felec            = felec*sw - rinv22*velec*dsw;
592             velec           *= sw;
593
594             /* Update potential sums from outer loop */
595             velecsum        += velec;
596
597             fscal            = felec;
598
599             /* Calculate temporary vectorial force */
600             tx               = fscal*dx22;
601             ty               = fscal*dy22;
602             tz               = fscal*dz22;
603
604             /* Update vectorial force */
605             fix2            += tx;
606             fiy2            += ty;
607             fiz2            += tz;
608             f[j_coord_offset+DIM*2+XX] -= tx;
609             f[j_coord_offset+DIM*2+YY] -= ty;
610             f[j_coord_offset+DIM*2+ZZ] -= tz;
611
612             }
613
614             /**************************
615              * CALCULATE INTERACTIONS *
616              **************************/
617
618             if (rsq23<rcutoff2)
619             {
620
621             r23              = rsq23*rinv23;
622
623             /* EWALD ELECTROSTATICS */
624
625             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
626             ewrt             = r23*ewtabscale;
627             ewitab           = ewrt;
628             eweps            = ewrt-ewitab;
629             ewitab           = 4*ewitab;
630             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
631             velec            = qq23*(rinv23-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
632             felec            = qq23*rinv23*(rinvsq23-felec);
633
634             d                = r23-rswitch;
635             d                = (d>0.0) ? d : 0.0;
636             d2               = d*d;
637             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
638
639             dsw              = d2*(swF2+d*(swF3+d*swF4));
640
641             /* Evaluate switch function */
642             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
643             felec            = felec*sw - rinv23*velec*dsw;
644             velec           *= sw;
645
646             /* Update potential sums from outer loop */
647             velecsum        += velec;
648
649             fscal            = felec;
650
651             /* Calculate temporary vectorial force */
652             tx               = fscal*dx23;
653             ty               = fscal*dy23;
654             tz               = fscal*dz23;
655
656             /* Update vectorial force */
657             fix2            += tx;
658             fiy2            += ty;
659             fiz2            += tz;
660             f[j_coord_offset+DIM*3+XX] -= tx;
661             f[j_coord_offset+DIM*3+YY] -= ty;
662             f[j_coord_offset+DIM*3+ZZ] -= tz;
663
664             }
665
666             /**************************
667              * CALCULATE INTERACTIONS *
668              **************************/
669
670             if (rsq31<rcutoff2)
671             {
672
673             r31              = rsq31*rinv31;
674
675             /* EWALD ELECTROSTATICS */
676
677             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
678             ewrt             = r31*ewtabscale;
679             ewitab           = ewrt;
680             eweps            = ewrt-ewitab;
681             ewitab           = 4*ewitab;
682             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
683             velec            = qq31*(rinv31-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
684             felec            = qq31*rinv31*(rinvsq31-felec);
685
686             d                = r31-rswitch;
687             d                = (d>0.0) ? d : 0.0;
688             d2               = d*d;
689             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
690
691             dsw              = d2*(swF2+d*(swF3+d*swF4));
692
693             /* Evaluate switch function */
694             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
695             felec            = felec*sw - rinv31*velec*dsw;
696             velec           *= sw;
697
698             /* Update potential sums from outer loop */
699             velecsum        += velec;
700
701             fscal            = felec;
702
703             /* Calculate temporary vectorial force */
704             tx               = fscal*dx31;
705             ty               = fscal*dy31;
706             tz               = fscal*dz31;
707
708             /* Update vectorial force */
709             fix3            += tx;
710             fiy3            += ty;
711             fiz3            += tz;
712             f[j_coord_offset+DIM*1+XX] -= tx;
713             f[j_coord_offset+DIM*1+YY] -= ty;
714             f[j_coord_offset+DIM*1+ZZ] -= tz;
715
716             }
717
718             /**************************
719              * CALCULATE INTERACTIONS *
720              **************************/
721
722             if (rsq32<rcutoff2)
723             {
724
725             r32              = rsq32*rinv32;
726
727             /* EWALD ELECTROSTATICS */
728
729             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
730             ewrt             = r32*ewtabscale;
731             ewitab           = ewrt;
732             eweps            = ewrt-ewitab;
733             ewitab           = 4*ewitab;
734             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
735             velec            = qq32*(rinv32-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
736             felec            = qq32*rinv32*(rinvsq32-felec);
737
738             d                = r32-rswitch;
739             d                = (d>0.0) ? d : 0.0;
740             d2               = d*d;
741             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
742
743             dsw              = d2*(swF2+d*(swF3+d*swF4));
744
745             /* Evaluate switch function */
746             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
747             felec            = felec*sw - rinv32*velec*dsw;
748             velec           *= sw;
749
750             /* Update potential sums from outer loop */
751             velecsum        += velec;
752
753             fscal            = felec;
754
755             /* Calculate temporary vectorial force */
756             tx               = fscal*dx32;
757             ty               = fscal*dy32;
758             tz               = fscal*dz32;
759
760             /* Update vectorial force */
761             fix3            += tx;
762             fiy3            += ty;
763             fiz3            += tz;
764             f[j_coord_offset+DIM*2+XX] -= tx;
765             f[j_coord_offset+DIM*2+YY] -= ty;
766             f[j_coord_offset+DIM*2+ZZ] -= tz;
767
768             }
769
770             /**************************
771              * CALCULATE INTERACTIONS *
772              **************************/
773
774             if (rsq33<rcutoff2)
775             {
776
777             r33              = rsq33*rinv33;
778
779             /* EWALD ELECTROSTATICS */
780
781             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
782             ewrt             = r33*ewtabscale;
783             ewitab           = ewrt;
784             eweps            = ewrt-ewitab;
785             ewitab           = 4*ewitab;
786             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
787             velec            = qq33*(rinv33-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
788             felec            = qq33*rinv33*(rinvsq33-felec);
789
790             d                = r33-rswitch;
791             d                = (d>0.0) ? d : 0.0;
792             d2               = d*d;
793             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
794
795             dsw              = d2*(swF2+d*(swF3+d*swF4));
796
797             /* Evaluate switch function */
798             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
799             felec            = felec*sw - rinv33*velec*dsw;
800             velec           *= sw;
801
802             /* Update potential sums from outer loop */
803             velecsum        += velec;
804
805             fscal            = felec;
806
807             /* Calculate temporary vectorial force */
808             tx               = fscal*dx33;
809             ty               = fscal*dy33;
810             tz               = fscal*dz33;
811
812             /* Update vectorial force */
813             fix3            += tx;
814             fiy3            += ty;
815             fiz3            += tz;
816             f[j_coord_offset+DIM*3+XX] -= tx;
817             f[j_coord_offset+DIM*3+YY] -= ty;
818             f[j_coord_offset+DIM*3+ZZ] -= tz;
819
820             }
821
822             /* Inner loop uses 601 flops */
823         }
824         /* End of innermost loop */
825
826         tx = ty = tz = 0;
827         f[i_coord_offset+DIM*0+XX] += fix0;
828         f[i_coord_offset+DIM*0+YY] += fiy0;
829         f[i_coord_offset+DIM*0+ZZ] += fiz0;
830         tx                         += fix0;
831         ty                         += fiy0;
832         tz                         += fiz0;
833         f[i_coord_offset+DIM*1+XX] += fix1;
834         f[i_coord_offset+DIM*1+YY] += fiy1;
835         f[i_coord_offset+DIM*1+ZZ] += fiz1;
836         tx                         += fix1;
837         ty                         += fiy1;
838         tz                         += fiz1;
839         f[i_coord_offset+DIM*2+XX] += fix2;
840         f[i_coord_offset+DIM*2+YY] += fiy2;
841         f[i_coord_offset+DIM*2+ZZ] += fiz2;
842         tx                         += fix2;
843         ty                         += fiy2;
844         tz                         += fiz2;
845         f[i_coord_offset+DIM*3+XX] += fix3;
846         f[i_coord_offset+DIM*3+YY] += fiy3;
847         f[i_coord_offset+DIM*3+ZZ] += fiz3;
848         tx                         += fix3;
849         ty                         += fiy3;
850         tz                         += fiz3;
851         fshift[i_shift_offset+XX]  += tx;
852         fshift[i_shift_offset+YY]  += ty;
853         fshift[i_shift_offset+ZZ]  += tz;
854
855         ggid                        = gid[iidx];
856         /* Update potential energies */
857         kernel_data->energygrp_elec[ggid] += velecsum;
858         kernel_data->energygrp_vdw[ggid] += vvdwsum;
859
860         /* Increment number of inner iterations */
861         inneriter                  += j_index_end - j_index_start;
862
863         /* Outer loop uses 41 flops */
864     }
865
866     /* Increment number of outer iterations */
867     outeriter        += nri;
868
869     /* Update outer/inner flops */
870
871     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4W4_VF,outeriter*41 + inneriter*601);
872 }
873 /*
874  * Gromacs nonbonded kernel:   nb_kernel_ElecEwSw_VdwBhamSw_GeomW4W4_F_c
875  * Electrostatics interaction: Ewald
876  * VdW interaction:            Buckingham
877  * Geometry:                   Water4-Water4
878  * Calculate force/pot:        Force
879  */
880 void
881 nb_kernel_ElecEwSw_VdwBhamSw_GeomW4W4_F_c
882                     (t_nblist                    * gmx_restrict       nlist,
883                      rvec                        * gmx_restrict          xx,
884                      rvec                        * gmx_restrict          ff,
885                      t_forcerec                  * gmx_restrict          fr,
886                      t_mdatoms                   * gmx_restrict     mdatoms,
887                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
888                      t_nrnb                      * gmx_restrict        nrnb)
889 {
890     int              i_shift_offset,i_coord_offset,j_coord_offset;
891     int              j_index_start,j_index_end;
892     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
893     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
894     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
895     real             *shiftvec,*fshift,*x,*f;
896     int              vdwioffset0;
897     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
898     int              vdwioffset1;
899     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
900     int              vdwioffset2;
901     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
902     int              vdwioffset3;
903     real             ix3,iy3,iz3,fix3,fiy3,fiz3,iq3,isai3;
904     int              vdwjidx0;
905     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
906     int              vdwjidx1;
907     real             jx1,jy1,jz1,fjx1,fjy1,fjz1,jq1,isaj1;
908     int              vdwjidx2;
909     real             jx2,jy2,jz2,fjx2,fjy2,fjz2,jq2,isaj2;
910     int              vdwjidx3;
911     real             jx3,jy3,jz3,fjx3,fjy3,fjz3,jq3,isaj3;
912     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
913     real             dx11,dy11,dz11,rsq11,rinv11,rinvsq11,r11,qq11,c6_11,c12_11,cexp1_11,cexp2_11;
914     real             dx12,dy12,dz12,rsq12,rinv12,rinvsq12,r12,qq12,c6_12,c12_12,cexp1_12,cexp2_12;
915     real             dx13,dy13,dz13,rsq13,rinv13,rinvsq13,r13,qq13,c6_13,c12_13,cexp1_13,cexp2_13;
916     real             dx21,dy21,dz21,rsq21,rinv21,rinvsq21,r21,qq21,c6_21,c12_21,cexp1_21,cexp2_21;
917     real             dx22,dy22,dz22,rsq22,rinv22,rinvsq22,r22,qq22,c6_22,c12_22,cexp1_22,cexp2_22;
918     real             dx23,dy23,dz23,rsq23,rinv23,rinvsq23,r23,qq23,c6_23,c12_23,cexp1_23,cexp2_23;
919     real             dx31,dy31,dz31,rsq31,rinv31,rinvsq31,r31,qq31,c6_31,c12_31,cexp1_31,cexp2_31;
920     real             dx32,dy32,dz32,rsq32,rinv32,rinvsq32,r32,qq32,c6_32,c12_32,cexp1_32,cexp2_32;
921     real             dx33,dy33,dz33,rsq33,rinv33,rinvsq33,r33,qq33,c6_33,c12_33,cexp1_33,cexp2_33;
922     real             velec,felec,velecsum,facel,crf,krf,krf2;
923     real             *charge;
924     int              nvdwtype;
925     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
926     int              *vdwtype;
927     real             *vdwparam;
928     int              ewitab;
929     real             ewtabscale,eweps,sh_ewald,ewrt,ewtabhalfspace;
930     real             *ewtab;
931     real             rswitch,swV3,swV4,swV5,swF2,swF3,swF4,d,d2,sw,dsw;
932
933     x                = xx[0];
934     f                = ff[0];
935
936     nri              = nlist->nri;
937     iinr             = nlist->iinr;
938     jindex           = nlist->jindex;
939     jjnr             = nlist->jjnr;
940     shiftidx         = nlist->shift;
941     gid              = nlist->gid;
942     shiftvec         = fr->shift_vec[0];
943     fshift           = fr->fshift[0];
944     facel            = fr->epsfac;
945     charge           = mdatoms->chargeA;
946     nvdwtype         = fr->ntype;
947     vdwparam         = fr->nbfp;
948     vdwtype          = mdatoms->typeA;
949
950     sh_ewald         = fr->ic->sh_ewald;
951     ewtab            = fr->ic->tabq_coul_FDV0;
952     ewtabscale       = fr->ic->tabq_scale;
953     ewtabhalfspace   = 0.5/ewtabscale;
954
955     /* Setup water-specific parameters */
956     inr              = nlist->iinr[0];
957     iq1              = facel*charge[inr+1];
958     iq2              = facel*charge[inr+2];
959     iq3              = facel*charge[inr+3];
960     vdwioffset0      = 3*nvdwtype*vdwtype[inr+0];
961
962     jq1              = charge[inr+1];
963     jq2              = charge[inr+2];
964     jq3              = charge[inr+3];
965     vdwjidx0         = 3*vdwtype[inr+0];
966     c6_00            = vdwparam[vdwioffset0+vdwjidx0];
967     cexp1_00         = vdwparam[vdwioffset0+vdwjidx0+1];
968     cexp2_00         = vdwparam[vdwioffset0+vdwjidx0+2];
969     qq11             = iq1*jq1;
970     qq12             = iq1*jq2;
971     qq13             = iq1*jq3;
972     qq21             = iq2*jq1;
973     qq22             = iq2*jq2;
974     qq23             = iq2*jq3;
975     qq31             = iq3*jq1;
976     qq32             = iq3*jq2;
977     qq33             = iq3*jq3;
978
979     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
980     rcutoff          = fr->rcoulomb;
981     rcutoff2         = rcutoff*rcutoff;
982
983     rswitch          = fr->rcoulomb_switch;
984     /* Setup switch parameters */
985     d                = rcutoff-rswitch;
986     swV3             = -10.0/(d*d*d);
987     swV4             =  15.0/(d*d*d*d);
988     swV5             =  -6.0/(d*d*d*d*d);
989     swF2             = -30.0/(d*d*d);
990     swF3             =  60.0/(d*d*d*d);
991     swF4             = -30.0/(d*d*d*d*d);
992
993     outeriter        = 0;
994     inneriter        = 0;
995
996     /* Start outer loop over neighborlists */
997     for(iidx=0; iidx<nri; iidx++)
998     {
999         /* Load shift vector for this list */
1000         i_shift_offset   = DIM*shiftidx[iidx];
1001         shX              = shiftvec[i_shift_offset+XX];
1002         shY              = shiftvec[i_shift_offset+YY];
1003         shZ              = shiftvec[i_shift_offset+ZZ];
1004
1005         /* Load limits for loop over neighbors */
1006         j_index_start    = jindex[iidx];
1007         j_index_end      = jindex[iidx+1];
1008
1009         /* Get outer coordinate index */
1010         inr              = iinr[iidx];
1011         i_coord_offset   = DIM*inr;
1012
1013         /* Load i particle coords and add shift vector */
1014         ix0              = shX + x[i_coord_offset+DIM*0+XX];
1015         iy0              = shY + x[i_coord_offset+DIM*0+YY];
1016         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
1017         ix1              = shX + x[i_coord_offset+DIM*1+XX];
1018         iy1              = shY + x[i_coord_offset+DIM*1+YY];
1019         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
1020         ix2              = shX + x[i_coord_offset+DIM*2+XX];
1021         iy2              = shY + x[i_coord_offset+DIM*2+YY];
1022         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
1023         ix3              = shX + x[i_coord_offset+DIM*3+XX];
1024         iy3              = shY + x[i_coord_offset+DIM*3+YY];
1025         iz3              = shZ + x[i_coord_offset+DIM*3+ZZ];
1026
1027         fix0             = 0.0;
1028         fiy0             = 0.0;
1029         fiz0             = 0.0;
1030         fix1             = 0.0;
1031         fiy1             = 0.0;
1032         fiz1             = 0.0;
1033         fix2             = 0.0;
1034         fiy2             = 0.0;
1035         fiz2             = 0.0;
1036         fix3             = 0.0;
1037         fiy3             = 0.0;
1038         fiz3             = 0.0;
1039
1040         /* Start inner kernel loop */
1041         for(jidx=j_index_start; jidx<j_index_end; jidx++)
1042         {
1043             /* Get j neighbor index, and coordinate index */
1044             jnr              = jjnr[jidx];
1045             j_coord_offset   = DIM*jnr;
1046
1047             /* load j atom coordinates */
1048             jx0              = x[j_coord_offset+DIM*0+XX];
1049             jy0              = x[j_coord_offset+DIM*0+YY];
1050             jz0              = x[j_coord_offset+DIM*0+ZZ];
1051             jx1              = x[j_coord_offset+DIM*1+XX];
1052             jy1              = x[j_coord_offset+DIM*1+YY];
1053             jz1              = x[j_coord_offset+DIM*1+ZZ];
1054             jx2              = x[j_coord_offset+DIM*2+XX];
1055             jy2              = x[j_coord_offset+DIM*2+YY];
1056             jz2              = x[j_coord_offset+DIM*2+ZZ];
1057             jx3              = x[j_coord_offset+DIM*3+XX];
1058             jy3              = x[j_coord_offset+DIM*3+YY];
1059             jz3              = x[j_coord_offset+DIM*3+ZZ];
1060
1061             /* Calculate displacement vector */
1062             dx00             = ix0 - jx0;
1063             dy00             = iy0 - jy0;
1064             dz00             = iz0 - jz0;
1065             dx11             = ix1 - jx1;
1066             dy11             = iy1 - jy1;
1067             dz11             = iz1 - jz1;
1068             dx12             = ix1 - jx2;
1069             dy12             = iy1 - jy2;
1070             dz12             = iz1 - jz2;
1071             dx13             = ix1 - jx3;
1072             dy13             = iy1 - jy3;
1073             dz13             = iz1 - jz3;
1074             dx21             = ix2 - jx1;
1075             dy21             = iy2 - jy1;
1076             dz21             = iz2 - jz1;
1077             dx22             = ix2 - jx2;
1078             dy22             = iy2 - jy2;
1079             dz22             = iz2 - jz2;
1080             dx23             = ix2 - jx3;
1081             dy23             = iy2 - jy3;
1082             dz23             = iz2 - jz3;
1083             dx31             = ix3 - jx1;
1084             dy31             = iy3 - jy1;
1085             dz31             = iz3 - jz1;
1086             dx32             = ix3 - jx2;
1087             dy32             = iy3 - jy2;
1088             dz32             = iz3 - jz2;
1089             dx33             = ix3 - jx3;
1090             dy33             = iy3 - jy3;
1091             dz33             = iz3 - jz3;
1092
1093             /* Calculate squared distance and things based on it */
1094             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
1095             rsq11            = dx11*dx11+dy11*dy11+dz11*dz11;
1096             rsq12            = dx12*dx12+dy12*dy12+dz12*dz12;
1097             rsq13            = dx13*dx13+dy13*dy13+dz13*dz13;
1098             rsq21            = dx21*dx21+dy21*dy21+dz21*dz21;
1099             rsq22            = dx22*dx22+dy22*dy22+dz22*dz22;
1100             rsq23            = dx23*dx23+dy23*dy23+dz23*dz23;
1101             rsq31            = dx31*dx31+dy31*dy31+dz31*dz31;
1102             rsq32            = dx32*dx32+dy32*dy32+dz32*dz32;
1103             rsq33            = dx33*dx33+dy33*dy33+dz33*dz33;
1104
1105             rinv00           = gmx_invsqrt(rsq00);
1106             rinv11           = gmx_invsqrt(rsq11);
1107             rinv12           = gmx_invsqrt(rsq12);
1108             rinv13           = gmx_invsqrt(rsq13);
1109             rinv21           = gmx_invsqrt(rsq21);
1110             rinv22           = gmx_invsqrt(rsq22);
1111             rinv23           = gmx_invsqrt(rsq23);
1112             rinv31           = gmx_invsqrt(rsq31);
1113             rinv32           = gmx_invsqrt(rsq32);
1114             rinv33           = gmx_invsqrt(rsq33);
1115
1116             rinvsq00         = rinv00*rinv00;
1117             rinvsq11         = rinv11*rinv11;
1118             rinvsq12         = rinv12*rinv12;
1119             rinvsq13         = rinv13*rinv13;
1120             rinvsq21         = rinv21*rinv21;
1121             rinvsq22         = rinv22*rinv22;
1122             rinvsq23         = rinv23*rinv23;
1123             rinvsq31         = rinv31*rinv31;
1124             rinvsq32         = rinv32*rinv32;
1125             rinvsq33         = rinv33*rinv33;
1126
1127             /**************************
1128              * CALCULATE INTERACTIONS *
1129              **************************/
1130
1131             if (rsq00<rcutoff2)
1132             {
1133
1134             r00              = rsq00*rinv00;
1135
1136             /* BUCKINGHAM DISPERSION/REPULSION */
1137             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
1138             vvdw6            = c6_00*rinvsix;
1139             br               = cexp2_00*r00;
1140             vvdwexp          = cexp1_00*exp(-br);
1141             vvdw             = vvdwexp - vvdw6*(1.0/6.0);
1142             fvdw             = (br*vvdwexp-vvdw6)*rinvsq00;
1143
1144             d                = r00-rswitch;
1145             d                = (d>0.0) ? d : 0.0;
1146             d2               = d*d;
1147             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
1148
1149             dsw              = d2*(swF2+d*(swF3+d*swF4));
1150
1151             /* Evaluate switch function */
1152             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
1153             fvdw             = fvdw*sw - rinv00*vvdw*dsw;
1154
1155             fscal            = fvdw;
1156
1157             /* Calculate temporary vectorial force */
1158             tx               = fscal*dx00;
1159             ty               = fscal*dy00;
1160             tz               = fscal*dz00;
1161
1162             /* Update vectorial force */
1163             fix0            += tx;
1164             fiy0            += ty;
1165             fiz0            += tz;
1166             f[j_coord_offset+DIM*0+XX] -= tx;
1167             f[j_coord_offset+DIM*0+YY] -= ty;
1168             f[j_coord_offset+DIM*0+ZZ] -= tz;
1169
1170             }
1171
1172             /**************************
1173              * CALCULATE INTERACTIONS *
1174              **************************/
1175
1176             if (rsq11<rcutoff2)
1177             {
1178
1179             r11              = rsq11*rinv11;
1180
1181             /* EWALD ELECTROSTATICS */
1182
1183             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1184             ewrt             = r11*ewtabscale;
1185             ewitab           = ewrt;
1186             eweps            = ewrt-ewitab;
1187             ewitab           = 4*ewitab;
1188             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
1189             velec            = qq11*(rinv11-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
1190             felec            = qq11*rinv11*(rinvsq11-felec);
1191
1192             d                = r11-rswitch;
1193             d                = (d>0.0) ? d : 0.0;
1194             d2               = d*d;
1195             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
1196
1197             dsw              = d2*(swF2+d*(swF3+d*swF4));
1198
1199             /* Evaluate switch function */
1200             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
1201             felec            = felec*sw - rinv11*velec*dsw;
1202
1203             fscal            = felec;
1204
1205             /* Calculate temporary vectorial force */
1206             tx               = fscal*dx11;
1207             ty               = fscal*dy11;
1208             tz               = fscal*dz11;
1209
1210             /* Update vectorial force */
1211             fix1            += tx;
1212             fiy1            += ty;
1213             fiz1            += tz;
1214             f[j_coord_offset+DIM*1+XX] -= tx;
1215             f[j_coord_offset+DIM*1+YY] -= ty;
1216             f[j_coord_offset+DIM*1+ZZ] -= tz;
1217
1218             }
1219
1220             /**************************
1221              * CALCULATE INTERACTIONS *
1222              **************************/
1223
1224             if (rsq12<rcutoff2)
1225             {
1226
1227             r12              = rsq12*rinv12;
1228
1229             /* EWALD ELECTROSTATICS */
1230
1231             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1232             ewrt             = r12*ewtabscale;
1233             ewitab           = ewrt;
1234             eweps            = ewrt-ewitab;
1235             ewitab           = 4*ewitab;
1236             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
1237             velec            = qq12*(rinv12-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
1238             felec            = qq12*rinv12*(rinvsq12-felec);
1239
1240             d                = r12-rswitch;
1241             d                = (d>0.0) ? d : 0.0;
1242             d2               = d*d;
1243             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
1244
1245             dsw              = d2*(swF2+d*(swF3+d*swF4));
1246
1247             /* Evaluate switch function */
1248             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
1249             felec            = felec*sw - rinv12*velec*dsw;
1250
1251             fscal            = felec;
1252
1253             /* Calculate temporary vectorial force */
1254             tx               = fscal*dx12;
1255             ty               = fscal*dy12;
1256             tz               = fscal*dz12;
1257
1258             /* Update vectorial force */
1259             fix1            += tx;
1260             fiy1            += ty;
1261             fiz1            += tz;
1262             f[j_coord_offset+DIM*2+XX] -= tx;
1263             f[j_coord_offset+DIM*2+YY] -= ty;
1264             f[j_coord_offset+DIM*2+ZZ] -= tz;
1265
1266             }
1267
1268             /**************************
1269              * CALCULATE INTERACTIONS *
1270              **************************/
1271
1272             if (rsq13<rcutoff2)
1273             {
1274
1275             r13              = rsq13*rinv13;
1276
1277             /* EWALD ELECTROSTATICS */
1278
1279             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1280             ewrt             = r13*ewtabscale;
1281             ewitab           = ewrt;
1282             eweps            = ewrt-ewitab;
1283             ewitab           = 4*ewitab;
1284             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
1285             velec            = qq13*(rinv13-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
1286             felec            = qq13*rinv13*(rinvsq13-felec);
1287
1288             d                = r13-rswitch;
1289             d                = (d>0.0) ? d : 0.0;
1290             d2               = d*d;
1291             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
1292
1293             dsw              = d2*(swF2+d*(swF3+d*swF4));
1294
1295             /* Evaluate switch function */
1296             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
1297             felec            = felec*sw - rinv13*velec*dsw;
1298
1299             fscal            = felec;
1300
1301             /* Calculate temporary vectorial force */
1302             tx               = fscal*dx13;
1303             ty               = fscal*dy13;
1304             tz               = fscal*dz13;
1305
1306             /* Update vectorial force */
1307             fix1            += tx;
1308             fiy1            += ty;
1309             fiz1            += tz;
1310             f[j_coord_offset+DIM*3+XX] -= tx;
1311             f[j_coord_offset+DIM*3+YY] -= ty;
1312             f[j_coord_offset+DIM*3+ZZ] -= tz;
1313
1314             }
1315
1316             /**************************
1317              * CALCULATE INTERACTIONS *
1318              **************************/
1319
1320             if (rsq21<rcutoff2)
1321             {
1322
1323             r21              = rsq21*rinv21;
1324
1325             /* EWALD ELECTROSTATICS */
1326
1327             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1328             ewrt             = r21*ewtabscale;
1329             ewitab           = ewrt;
1330             eweps            = ewrt-ewitab;
1331             ewitab           = 4*ewitab;
1332             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
1333             velec            = qq21*(rinv21-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
1334             felec            = qq21*rinv21*(rinvsq21-felec);
1335
1336             d                = r21-rswitch;
1337             d                = (d>0.0) ? d : 0.0;
1338             d2               = d*d;
1339             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
1340
1341             dsw              = d2*(swF2+d*(swF3+d*swF4));
1342
1343             /* Evaluate switch function */
1344             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
1345             felec            = felec*sw - rinv21*velec*dsw;
1346
1347             fscal            = felec;
1348
1349             /* Calculate temporary vectorial force */
1350             tx               = fscal*dx21;
1351             ty               = fscal*dy21;
1352             tz               = fscal*dz21;
1353
1354             /* Update vectorial force */
1355             fix2            += tx;
1356             fiy2            += ty;
1357             fiz2            += tz;
1358             f[j_coord_offset+DIM*1+XX] -= tx;
1359             f[j_coord_offset+DIM*1+YY] -= ty;
1360             f[j_coord_offset+DIM*1+ZZ] -= tz;
1361
1362             }
1363
1364             /**************************
1365              * CALCULATE INTERACTIONS *
1366              **************************/
1367
1368             if (rsq22<rcutoff2)
1369             {
1370
1371             r22              = rsq22*rinv22;
1372
1373             /* EWALD ELECTROSTATICS */
1374
1375             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1376             ewrt             = r22*ewtabscale;
1377             ewitab           = ewrt;
1378             eweps            = ewrt-ewitab;
1379             ewitab           = 4*ewitab;
1380             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
1381             velec            = qq22*(rinv22-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
1382             felec            = qq22*rinv22*(rinvsq22-felec);
1383
1384             d                = r22-rswitch;
1385             d                = (d>0.0) ? d : 0.0;
1386             d2               = d*d;
1387             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
1388
1389             dsw              = d2*(swF2+d*(swF3+d*swF4));
1390
1391             /* Evaluate switch function */
1392             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
1393             felec            = felec*sw - rinv22*velec*dsw;
1394
1395             fscal            = felec;
1396
1397             /* Calculate temporary vectorial force */
1398             tx               = fscal*dx22;
1399             ty               = fscal*dy22;
1400             tz               = fscal*dz22;
1401
1402             /* Update vectorial force */
1403             fix2            += tx;
1404             fiy2            += ty;
1405             fiz2            += tz;
1406             f[j_coord_offset+DIM*2+XX] -= tx;
1407             f[j_coord_offset+DIM*2+YY] -= ty;
1408             f[j_coord_offset+DIM*2+ZZ] -= tz;
1409
1410             }
1411
1412             /**************************
1413              * CALCULATE INTERACTIONS *
1414              **************************/
1415
1416             if (rsq23<rcutoff2)
1417             {
1418
1419             r23              = rsq23*rinv23;
1420
1421             /* EWALD ELECTROSTATICS */
1422
1423             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1424             ewrt             = r23*ewtabscale;
1425             ewitab           = ewrt;
1426             eweps            = ewrt-ewitab;
1427             ewitab           = 4*ewitab;
1428             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
1429             velec            = qq23*(rinv23-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
1430             felec            = qq23*rinv23*(rinvsq23-felec);
1431
1432             d                = r23-rswitch;
1433             d                = (d>0.0) ? d : 0.0;
1434             d2               = d*d;
1435             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
1436
1437             dsw              = d2*(swF2+d*(swF3+d*swF4));
1438
1439             /* Evaluate switch function */
1440             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
1441             felec            = felec*sw - rinv23*velec*dsw;
1442
1443             fscal            = felec;
1444
1445             /* Calculate temporary vectorial force */
1446             tx               = fscal*dx23;
1447             ty               = fscal*dy23;
1448             tz               = fscal*dz23;
1449
1450             /* Update vectorial force */
1451             fix2            += tx;
1452             fiy2            += ty;
1453             fiz2            += tz;
1454             f[j_coord_offset+DIM*3+XX] -= tx;
1455             f[j_coord_offset+DIM*3+YY] -= ty;
1456             f[j_coord_offset+DIM*3+ZZ] -= tz;
1457
1458             }
1459
1460             /**************************
1461              * CALCULATE INTERACTIONS *
1462              **************************/
1463
1464             if (rsq31<rcutoff2)
1465             {
1466
1467             r31              = rsq31*rinv31;
1468
1469             /* EWALD ELECTROSTATICS */
1470
1471             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1472             ewrt             = r31*ewtabscale;
1473             ewitab           = ewrt;
1474             eweps            = ewrt-ewitab;
1475             ewitab           = 4*ewitab;
1476             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
1477             velec            = qq31*(rinv31-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
1478             felec            = qq31*rinv31*(rinvsq31-felec);
1479
1480             d                = r31-rswitch;
1481             d                = (d>0.0) ? d : 0.0;
1482             d2               = d*d;
1483             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
1484
1485             dsw              = d2*(swF2+d*(swF3+d*swF4));
1486
1487             /* Evaluate switch function */
1488             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
1489             felec            = felec*sw - rinv31*velec*dsw;
1490
1491             fscal            = felec;
1492
1493             /* Calculate temporary vectorial force */
1494             tx               = fscal*dx31;
1495             ty               = fscal*dy31;
1496             tz               = fscal*dz31;
1497
1498             /* Update vectorial force */
1499             fix3            += tx;
1500             fiy3            += ty;
1501             fiz3            += tz;
1502             f[j_coord_offset+DIM*1+XX] -= tx;
1503             f[j_coord_offset+DIM*1+YY] -= ty;
1504             f[j_coord_offset+DIM*1+ZZ] -= tz;
1505
1506             }
1507
1508             /**************************
1509              * CALCULATE INTERACTIONS *
1510              **************************/
1511
1512             if (rsq32<rcutoff2)
1513             {
1514
1515             r32              = rsq32*rinv32;
1516
1517             /* EWALD ELECTROSTATICS */
1518
1519             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1520             ewrt             = r32*ewtabscale;
1521             ewitab           = ewrt;
1522             eweps            = ewrt-ewitab;
1523             ewitab           = 4*ewitab;
1524             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
1525             velec            = qq32*(rinv32-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
1526             felec            = qq32*rinv32*(rinvsq32-felec);
1527
1528             d                = r32-rswitch;
1529             d                = (d>0.0) ? d : 0.0;
1530             d2               = d*d;
1531             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
1532
1533             dsw              = d2*(swF2+d*(swF3+d*swF4));
1534
1535             /* Evaluate switch function */
1536             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
1537             felec            = felec*sw - rinv32*velec*dsw;
1538
1539             fscal            = felec;
1540
1541             /* Calculate temporary vectorial force */
1542             tx               = fscal*dx32;
1543             ty               = fscal*dy32;
1544             tz               = fscal*dz32;
1545
1546             /* Update vectorial force */
1547             fix3            += tx;
1548             fiy3            += ty;
1549             fiz3            += tz;
1550             f[j_coord_offset+DIM*2+XX] -= tx;
1551             f[j_coord_offset+DIM*2+YY] -= ty;
1552             f[j_coord_offset+DIM*2+ZZ] -= tz;
1553
1554             }
1555
1556             /**************************
1557              * CALCULATE INTERACTIONS *
1558              **************************/
1559
1560             if (rsq33<rcutoff2)
1561             {
1562
1563             r33              = rsq33*rinv33;
1564
1565             /* EWALD ELECTROSTATICS */
1566
1567             /* Calculate Ewald table index by multiplying r with scale and truncate to integer */
1568             ewrt             = r33*ewtabscale;
1569             ewitab           = ewrt;
1570             eweps            = ewrt-ewitab;
1571             ewitab           = 4*ewitab;
1572             felec            = ewtab[ewitab]+eweps*ewtab[ewitab+1];
1573             velec            = qq33*(rinv33-(ewtab[ewitab+2]-ewtabhalfspace*eweps*(ewtab[ewitab]+felec)));
1574             felec            = qq33*rinv33*(rinvsq33-felec);
1575
1576             d                = r33-rswitch;
1577             d                = (d>0.0) ? d : 0.0;
1578             d2               = d*d;
1579             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
1580
1581             dsw              = d2*(swF2+d*(swF3+d*swF4));
1582
1583             /* Evaluate switch function */
1584             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
1585             felec            = felec*sw - rinv33*velec*dsw;
1586
1587             fscal            = felec;
1588
1589             /* Calculate temporary vectorial force */
1590             tx               = fscal*dx33;
1591             ty               = fscal*dy33;
1592             tz               = fscal*dz33;
1593
1594             /* Update vectorial force */
1595             fix3            += tx;
1596             fiy3            += ty;
1597             fiz3            += tz;
1598             f[j_coord_offset+DIM*3+XX] -= tx;
1599             f[j_coord_offset+DIM*3+YY] -= ty;
1600             f[j_coord_offset+DIM*3+ZZ] -= tz;
1601
1602             }
1603
1604             /* Inner loop uses 581 flops */
1605         }
1606         /* End of innermost loop */
1607
1608         tx = ty = tz = 0;
1609         f[i_coord_offset+DIM*0+XX] += fix0;
1610         f[i_coord_offset+DIM*0+YY] += fiy0;
1611         f[i_coord_offset+DIM*0+ZZ] += fiz0;
1612         tx                         += fix0;
1613         ty                         += fiy0;
1614         tz                         += fiz0;
1615         f[i_coord_offset+DIM*1+XX] += fix1;
1616         f[i_coord_offset+DIM*1+YY] += fiy1;
1617         f[i_coord_offset+DIM*1+ZZ] += fiz1;
1618         tx                         += fix1;
1619         ty                         += fiy1;
1620         tz                         += fiz1;
1621         f[i_coord_offset+DIM*2+XX] += fix2;
1622         f[i_coord_offset+DIM*2+YY] += fiy2;
1623         f[i_coord_offset+DIM*2+ZZ] += fiz2;
1624         tx                         += fix2;
1625         ty                         += fiy2;
1626         tz                         += fiz2;
1627         f[i_coord_offset+DIM*3+XX] += fix3;
1628         f[i_coord_offset+DIM*3+YY] += fiy3;
1629         f[i_coord_offset+DIM*3+ZZ] += fiz3;
1630         tx                         += fix3;
1631         ty                         += fiy3;
1632         tz                         += fiz3;
1633         fshift[i_shift_offset+XX]  += tx;
1634         fshift[i_shift_offset+YY]  += ty;
1635         fshift[i_shift_offset+ZZ]  += tz;
1636
1637         /* Increment number of inner iterations */
1638         inneriter                  += j_index_end - j_index_start;
1639
1640         /* Outer loop uses 39 flops */
1641     }
1642
1643     /* Increment number of outer iterations */
1644     outeriter        += nri;
1645
1646     /* Update outer/inner flops */
1647
1648     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W4W4_F,outeriter*39 + inneriter*581);
1649 }