diff --git a/src/cost.c b/src/cost.c
index 5fd8136..5643ed8 100644
--- a/src/cost.c
+++ b/src/cost.c
@@ -48,6 +48,27 @@
  * A lower value (closer to 0) is a more feasible attack.
  */
 int
+computeAttackCost (const System sys)
+{
+  // Use nice heuristic cf. work of Gijs Hollestelle. Hand-picked parameters.
+  int cost;
+
+  cost = 0;
+
+  //cost += get_semitrace_length ();
+
+  cost += 10 * selfInitiators (sys);
+  cost += 7 * selfResponders (sys);
+  cost += 10 * sys->num_regular_runs;
+  cost += 3 * countInitiators (sys);
+  cost += 2 * countBindingsDone ();
+  cost += 1 * sys->num_intruder_runs;
+
+  return cost;
+}
+
+//! Compute attack cost in different pruning contexts.
+int
 attackCost (const System sys)
 {
   if (switches.prune == 0)
@@ -72,21 +93,7 @@ attackCost (const System sys)
     }
   if (switches.prune == 2)
     {
-      // Use nice heuristic cf. work of Gijs Hollestelle. Hand-picked parameters.
-      int cost;
-
-      cost = 0;
-
-      //cost += get_semitrace_length ();
-
-      cost += 10 * selfInitiators (sys);
-      cost += 7 * selfResponders (sys);
-      cost += 10 * sys->num_regular_runs;
-      cost += 3 * countInitiators (sys);
-      cost += 2 * countBindingsDone ();
-      cost += 1 * sys->num_intruder_runs;
-
-      return cost;
+      return computeAttackCost (sys);
     }
   error ("Unknown pruning method (cost function not found)");
   return 0;
diff --git a/src/cost.h b/src/cost.h
index 3c66292..371fb1e 100644
--- a/src/cost.h
+++ b/src/cost.h
@@ -20,6 +20,7 @@
 #ifndef COST
 #define COST
 
+int computeAttackCost (const System sys);
 int attackCost (const System sys);
 
 #endif
diff --git a/src/dotout.c b/src/dotout.c
index 6de3fca..9bbca2d 100644
--- a/src/dotout.c
+++ b/src/dotout.c
@@ -28,6 +28,7 @@
 #include "debug.h"
 #include "error.h"
 #include "specialterm.h"
+#include "cost.h"
 
 extern Protocol INTRUDER;	// Pointers, to be set by the Init of arachne.c
 extern Role I_M;		// Same here.
@@ -1658,6 +1659,8 @@ dotSemiState (const System mysys)
   termPrintRemap (sys->current_claim->rolename);
   eprintf (", claim type ");
   termPrintRemap (sys->current_claim->type);
+  // For debugging:
+  eprintf (", cost %i", computeAttackCost (sys));
   eprintf ("\";\n");
 
   // Needed for the bindings later on: create graph