text: /* ----------------------------------------------------------------------
     LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
     http://lammps.sandia.gov, Sandia National Laboratories
     Steve Plimpton, sjplimp@sandia.gov
  
     This software is distributed under the GNU General Public License.
  
     See the README file in the top-level LAMMPS directory.
  ------------------------------------------------------------------------- */
  
  /* ----------------------------------------------------------------------
     Contributing author: Stefan Paquay (Eindhoven University of Technology)
     Most code borrowed from pair_morse_omp.cpp
  ------------------------------------------------------------------------- */
  
  #include <math.h>
  #include "pair_morse_smooth_linear_omp.h"
  #include "atom.h"
  #include "comm.h"
  #include "force.h"
  #include "neighbor.h"
  #include "neigh_list.h"
  
  #include "suffix.h"
  using namespace LAMMPS_NS;
  
  
  /* ---------------------------------------------------------------------- */
  
  PairMorseSmoothLinearOMP::PairMorseSmoothLinearOMP(LAMMPS *lmp) :
    PairMorseSmoothLinear(lmp), ThrOMP(lmp, THR_PAIR)
  {
    suffix_flag |= Suffix::OMP;
    respa_enable = 0;
  }
  
  
  
  /* ---------------------------------------------------------------------- */
  
  void PairMorseSmoothLinearOMP::compute(int eflag, int vflag)
  {
    if (eflag || vflag) {
      ev_setup(eflag,vflag);
    } else evflag = vflag_fdotr = 0;
  
    const int nall = atom->nlocal + atom->nghost;
    const int nthreads = comm->nthreads;
    const int inum = list->inum;
  
  #if defined(_OPENMP)
  #pragma omp parallel default(none) shared(eflag,vflag)
  #endif
    {
      int ifrom, ito, tid;
  
      loop_setup_thr(ifrom, ito, tid, inum, nthreads);
      ThrData *thr = fix->get_thr(tid);
      thr->timer(Timer::START);
      ev_setup_thr(eflag, vflag, nall, eatom, vatom, thr);
  
      if (evflag) {
        if (eflag) {
          if (force->newton_pair) eval<1,1,1>(ifrom, ito, thr);
          else eval<1,1,0>(ifrom, ito, thr);
        } else {
          if (force->newton_pair) eval<1,0,1>(ifrom, ito, thr);
          else eval<1,0,0>(ifrom, ito, thr);
        }
      } else {
        if (force->newton_pair) eval<0,0,1>(ifrom, ito, thr);
        else eval<0,0,0>(ifrom, ito, thr);
      }
  
      thr->timer(Timer::PAIR);
      reduce_thr(this, eflag, vflag, thr);
    } // end of omp parallel region
  }
  
  
  
  template <int EVFLAG, int EFLAG, int NEWTON_PAIR>
  void PairMorseSmoothLinearOMP::eval(int iifrom, int iito, ThrData * const thr)
  {
    int i,j,ii,jj,jnum,itype,jtype;
    double xtmp,ytmp,ztmp,delx,dely,delz,evdwl,fpair,fpartial;
    double rsq,r,dr,dexp,factor_lj;
    int *ilist,*jlist,*numneigh,**firstneigh;
  
    evdwl = 0.0;
  
    const dbl3_t * _noalias const x = (dbl3_t *) atom->x[0];
    dbl3_t * _noalias const f = (dbl3_t *) thr->get_f()[0];
    const int * _noalias const type = atom->type;
    const int nlocal = atom->nlocal;
    const double * _noalias const special_lj = force->special_lj;
    double fxtmp,fytmp,fztmp;
  
    ilist = list->ilist;
    numneigh = list->numneigh;
    firstneigh = list->firstneigh;
  
    // loop over neighbors of my atoms
  
    for (ii = iifrom; ii < iito; ++ii) {
  
      i = ilist[ii];
      xtmp = x[i].x;
      ytmp = x[i].y;
      ztmp = x[i].z;
      itype = type[i];
      jlist = firstneigh[i];
      jnum = numneigh[i];
      fxtmp=fytmp=fztmp=0.0;
  
      for (jj = 0; jj < jnum; jj++) {
        j = jlist[jj];
        factor_lj = special_lj[sbmask(j)];
        j &= NEIGHMASK;
  
        delx = xtmp - x[j].x;
        dely = ytmp - x[j].y;
        delz = ztmp - x[j].z;
        rsq = delx*delx + dely*dely + delz*delz;
        jtype = type[j];
  
        if (rsq < cutsq[itype][jtype]) {
          r = sqrt(rsq);
          dr = r - r0[itype][jtype];
          dexp = exp(-alpha[itype][jtype] * dr);
  
          fpartial = morse1[itype][jtype] * (dexp*dexp - dexp) / r;
          fpair = factor_lj * ( fpartial - der_at_cutoff[itype][jtype] / r);
  
          fxtmp += delx*fpair;
          fytmp += dely*fpair;
          fztmp += delz*fpair;
          if (NEWTON_PAIR || j < nlocal) {
            f[j].x -= delx*fpair;
            f[j].y -= dely*fpair;
            f[j].z -= delz*fpair;
          }
  
          if (EFLAG) {
            evdwl = d0[itype][jtype] * (dexp*dexp - 2.0*dexp) -
  	          offset[itype][jtype];
            evdwl += ( r - cut[itype][jtype] ) * der_at_cutoff[itype][jtype];
            evdwl *= factor_lj;
          }
  
          if (EVFLAG) ev_tally_thr(this,i,j,nlocal,NEWTON_PAIR,
                                   evdwl,0.0,fpair,delx,dely,delz,thr);
        }
      }
      f[i].x += fxtmp;
      f[i].y += fytmp;
      f[i].z += fztmp;
    }
  }
  
  /* ---------------------------------------------------------------------- */
  
  double PairMorseSmoothLinearOMP::memory_usage()
  {
    double bytes = memory_usage_thr();
    bytes += PairMorseSmoothLinear::memory_usage();
  
    return bytes;
  }
  