Updates based on GitHub; wrapped #ifndef and updated calculating_routing_usage comment in .h file.

Author: alanbu1

vpr/src/route/route_util.cpp

@@ -29,12 +29,14 @@ vtr::Matrix<float> calculate_routing_usage(t_rr_type rr_type, bool is_flat, bool
 
     //Record number of used resources in each x/y channel
     for (RRNodeId rr_node : rr_nodes) {
-        if (!is_print) {
-            t_draw_state* draw_state = get_draw_state_vars();
-            int layer_num = rr_graph.node_layer(rr_node);
-            if (!draw_state->draw_layer_display[layer_num].visible)
-                continue; // don't count usage if layer is not visible
-        }
+        #ifndef NO_GRAPHICS
+            if (!is_print) {
+                t_draw_state* draw_state = get_draw_state_vars();
+                int layer_num = rr_graph.node_layer(rr_node);
+                if (!draw_state->draw_layer_display[layer_num].visible)
+                    continue; // don't count usage if layer is not visible
+            }
+        #endif
 
         if (rr_type == CHANX) {
             VTR_ASSERT(rr_graph.node_type(rr_node) == CHANX);

vpr/src/route/route_util.h

@@ -7,11 +7,13 @@
 vtr::Matrix<float> calculate_routing_avail(t_rr_type rr_type);
 
 /**
- * @brief Calculates routing usage over entire grid
- * Collects all in-use nodes and records number of used resources
- * in each x/y channel. Takes into consideration visible layers
- * for multi-layered architectures. Also takes into consideration
- * if it is being printed, if so, layer visibility is ignored.
+ * @brief: Calculates and returns the usage over the entire grid for the specified
+ * type of rr_node to the usage array. The usage is recorded at each (x,y) location.
+ *
+ * @param rr_type: Type of rr_node that we are calculating the usage of; can be CHANX or CHANY
+ * @param is_flat: Is the flat router being used or not?
+ * @param only_visible: If true, only record the usage of rr_nodes on layers that are visible according to the current
+ * drawing settings.
  */
 vtr::Matrix<float> calculate_routing_usage(t_rr_type rr_type, bool is_flat, bool is_print);
 float routing_util(float used, float avail);