optimize twobody term by passing a const reference instead of a pointer (490b3402) · Commits · 郑智淋 / lammps

src/MANYBODY/pair_vashishta.cpp

+26 −25

Original line number	Diff line number	Diff line
		@@ -154,7 +154,7 @@ void PairVashishta::updateTables()
		double rsq = tabinnersq + idx*deltaR2;
		double fpair, eng;
		// call analytical version of two-body term function
		twobody(&params[ijparam], rsq, fpair, 1, eng, false);
		twobody(params[ijparam], rsq, fpair, 1, eng, false);
		forceTable[i][j][idx] = fpair;
		potentialTable[i][j][idx] = eng;
		}
		@@ -238,7 +238,7 @@ void PairVashishta::compute(int eflag, int vflag)
		if (x[j][2] == ztmp && x[j][1] == ytmp && x[j][0] < xtmp) continue;
		}

		twobody(&params[ijparam],rsq,fpair,eflag,evdwl, useTable);
		twobody(params[ijparam],rsq,fpair,eflag,evdwl, useTable);

		f[i][0] += delx*fpair;
		f[i][1] += dely*fpair;
		@@ -641,25 +641,26 @@ void PairVashishta::setup_params()

		/* ---------------------------------------------------------------------- */

		void PairVashishta::twobody(Param *param, double rsq, double &fforce,
		void PairVashishta::twobody(const Param &param, double rsq, double &fforce,
		int eflag, double &eng, bool tabulated)
		{
		if (tabulated) {
		if (rsq < tabinnersq) {
		sprintf(estr,"Pair distance < table inner cutoff: "
		"ijtype %d %d dist %g",param->ielement+1,param->jelement+1,sqrt(rsq));
		"ijtype %d %d dist %g",param.ielement+1,param.jelement+1,sqrt(rsq));
		error->one(FLERR,estr);
		}

		int tableIndex = (rsq - tabinnersq)*oneOverDeltaR2;
		double fraction = (rsq - tabinnersq)*oneOverDeltaR2 - tableIndex; // double - int will only keep the 0.xxxx part
		const int tableIndex = (rsq - tabinnersq)*oneOverDeltaR2;
		// double - int will only keep the 0.xxxx part
		const double fraction = (rsq - tabinnersq)*oneOverDeltaR2 - tableIndex;

		double force0 = forceTable[param->ielement][param->jelement][tableIndex];
		double force1 = forceTable[param->ielement][param->jelement][tableIndex+1];
		double force0 = forceTable[param.ielement][param.jelement][tableIndex];
		double force1 = forceTable[param.ielement][param.jelement][tableIndex+1];
		fforce = (1.0 - fraction)force0 + fractionforce1; // force is linearly interpolated between the two values
		if (evflag) {
		double energy0 = potentialTable[param->ielement][param->jelement][tableIndex];
		double energy1 = potentialTable[param->ielement][param->jelement][tableIndex+1];
		double energy0 = potentialTable[param.ielement][param.jelement][tableIndex];
		double energy1 = potentialTable[param.ielement][param.jelement][tableIndex+1];
		eng = (1.0 - fraction)energy0 + fractionenergy1;
		}
		} else {
		@@ -669,19 +670,19 @@ void PairVashishta::twobody(Param *param, double rsq, double &fforce,
		rinvsq = 1.0/rsq;
		r4inv = rinvsq*rinvsq;
		r6inv = rinvsq*r4inv;
		reta = pow(r,-param->eta);
		lam1r = r*param->lam1inv;
		lam4r = r*param->lam4inv;
		vc2 = param->zizj * exp(-lam1r)/r;
		vc3 = param->mbigd * r4inv*exp(-lam4r);

		fforce = (param->dvrc*r
		- (4.0vc3 + lam4rvc3+param->big6w*r6inv
		- param->hetareta - vc2 - lam1rvc2)
		reta = pow(r,-param.eta);
		lam1r = r*param.lam1inv;
		lam4r = r*param.lam4inv;
		vc2 = param.zizj * exp(-lam1r)/r;
		vc3 = param.mbigd * r4inv*exp(-lam4r);

		fforce = (param.dvrc*r
		- (4.0vc3 + lam4rvc3+param.big6w*r6inv
		- param.hetareta - vc2 - lam1rvc2)
		) * rinvsq;
		if (eflag) eng = param->bigh*reta
		+ vc2 - vc3 - param->bigw*r6inv
		- r*param->dvrc + param->c0;
		if (eflag) eng = param.bigh*reta
		+ vc2 - vc3 - param.bigw*r6inv
		- r*param.dvrc + param.c0;
		}
		}

src/MANYBODY/pair_vashishta.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -74,7 +74,7 @@ class PairVashishta : public Pair {
		void setup_params();
		void updateTables();
		void validateNeigh3Body();
		void twobody(Param *, double, double &, int, double &, bool tabulated = false);
		void twobody(const Param &, double, double &, int, double &, bool tabulated=false);
		void threebody(Param , Param , Param , double, double, double , double *,
		double , double , int, double &);
		};

src/USER-OMP/pair_vashishta_omp.cpp

+1 −1

Original line number	Diff line number	Diff line
		@@ -144,7 +144,7 @@ void PairVashishtaOMP::eval(int iifrom, int iito, ThrData * const thr)
		if (x[j].z == ztmp && x[j].y == ytmp && x[j].x < xtmp) continue;
		}

		twobody(&params[ijparam],rsq,fpair,EFLAG,evdwl,useTable);
		twobody(params[ijparam],rsq,fpair,EFLAG,evdwl,useTable);

		fxtmp += delx*fpair;
		fytmp += dely*fpair;

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