cngf-pf

commit 76e6b4ac97282ee09d512c61cda430007884b345
parent a715c6d8412ec46c3df15b56f94a8331d4717870
Author: Anders Damsgaard <anders@adamsgaard.dk>
Date:   Wed, 14 Jan 2026 21:16:46 +0100

perf(arrays): add early exit for max when threshold exceeded

Diffstat:
M
arrays.c
 | 
19
+++++++++++++++++++
M
arrays.h
 | 
1
+
M
simulation.c
 | 
4
++--

3 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/arrays.c b/arrays.c
@@ -174,6 +174,25 @@ max(const double *a, const int n)
 	return maxval;
 }
 
+/* Return maximum value in array, with early exit if threshold exceeded */
+double
+max_with_threshold(const double *a, const int n, const double threshold)
+{
+	int i;
+	double maxval;
+
+	check_magnitude(__func__, 1, n);
+	maxval = -INFINITY;
+	for (i = 0; i < n; ++i) {
+		if (a[i] > maxval)
+			maxval = a[i];
+		if (maxval > threshold)
+			return maxval;
+	}
+
+	return maxval;
+}
+
 /* Return smallest value in array `a` with size `n` */
 double
 min(const double *a, const int n)
diff --git a/arrays.h b/arrays.h
@@ -27,6 +27,7 @@ double * initval(const double value, const int n);
 double * empty(const int n);
 
 double max(const double *a, const int n);
+double max_with_threshold(const double *a, const int n, const double threshold);
 double min(const double *a, const int n);
 
 void print_array(const double *a, const int n);
diff --git a/simulation.c b/simulation.c
@@ -719,7 +719,7 @@ implicit_1d_sor_poisson_solver(struct simulation *sim,
 			                                  sim->dz,
 			                                  sim->xi,
 			                                  omega);
-		r_norm_max = max(sim->g_r_norm, sim->nz);
+		r_norm_max = max_with_threshold(sim->g_r_norm, sim->nz, rel_tol);
 
 		if (r_norm_max <= rel_tol) {
 			set_bc_dirichlet(sim->g_ghost, sim->nz, -1, 0.0);
@@ -887,7 +887,7 @@ coupled_shear_solver(struct simulation *sim,
 			if (sim->transient) {
 				for (i = 0; i < sim->nz; ++i)
 					sim->g_r_norm[i] = fabs(residual(sim->phi_dot[i], sim->old_val[i]));
-				r_norm_max = max(sim->g_r_norm, sim->nz);
+				r_norm_max = max_with_threshold(sim->g_r_norm, sim->nz, rel_tol);
 				if (r_norm_max <= rel_tol && coupled_iter > 0)
 					break;
 				if (coupled_iter++ >= max_iter) {