diff --git a/common/route/router2.cc b/common/route/router2.cc
index 4bec4f31..7ae57f5a 100644
--- a/common/route/router2.cc
+++ b/common/route/router2.cc
@@ -95,16 +95,15 @@ struct Router2
         // Historical congestion cost
         int curr_cong = 0;
         float hist_cong_cost = 1.0;
-        // Wire is unavailable as locked to another arc
-        bool unavailable = false;
         // This wire has to be used for this net
         int reserved_net = -1;
+        static constexpr int RESERVED_UNAVAILABLE = -2;
         // The notional location of the wire, to guarantee thread safety
         int16_t x = 0, y = 0;
         // Visit data
         PipId pip_fwd, pip_bwd;
-        bool visited_fwd = false, visited_bwd = false;
-        float cost_fwd = 0.0, cost_bwd = 0.0;
+        static constexpr float NOT_VISITED = std::numeric_limits<float>::max();
+        float cost_fwd = NOT_VISITED, cost_bwd = NOT_VISITED;
     };
 
     struct PerResourceData
@@ -226,7 +225,7 @@ struct Router2
                     if (bound->wires.at(wire).strength == STRENGTH_PLACER) {
                         pwd.reserved_net = bound->udata;
                     } else if (bound->wires.at(wire).strength > STRENGTH_PLACER) {
-                        pwd.unavailable = true;
+                        pwd.reserved_net = PerWireData::RESERVED_UNAVAILABLE;
                     }
                 }
             }
@@ -577,7 +576,7 @@ struct Router2
         // and LUT
         if (iter_count > 7)
             return false; // heuristic to assume we've hit general routing
-        if (wire_data(wire).unavailable)
+        if (wire_data(wire).reserved_net == PerWireData::RESERVED_UNAVAILABLE)
             return true;
         if (wire_data(wire).reserved_net != -1 && wire_data(wire).reserved_net != net->udata)
             return true; // reserved for another net
@@ -721,10 +720,8 @@ struct Router2
         for (auto w : t.dirty_wires) {
             flat_wires[w].pip_fwd = PipId();
             flat_wires[w].pip_bwd = PipId();
-            flat_wires[w].visited_fwd = false;
-            flat_wires[w].visited_bwd = false;
-            flat_wires[w].cost_fwd = 0.0;
-            flat_wires[w].cost_bwd = 0.0;
+            flat_wires[w].cost_fwd = PerWireData::NOT_VISITED;
+            flat_wires[w].cost_bwd = PerWireData::NOT_VISITED;
         }
         t.dirty_wires.clear();
     }
@@ -758,29 +755,27 @@ struct Router2
     void set_visited_fwd(ThreadContext &t, int wire, PipId pip, float cost)
     {
         auto &wd = flat_wires.at(wire);
-        if (!wd.visited_fwd && !wd.visited_bwd)
+        if (wd.cost_fwd == PerWireData::NOT_VISITED && wd.cost_bwd == PerWireData::NOT_VISITED)
             t.dirty_wires.push_back(wire);
         wd.pip_fwd = pip;
-        wd.visited_fwd = true;
         wd.cost_fwd = cost;
     }
     void set_visited_bwd(ThreadContext &t, int wire, PipId pip, float cost)
     {
         auto &wd = flat_wires.at(wire);
-        if (!wd.visited_fwd && !wd.visited_bwd)
+        if (wd.cost_fwd == PerWireData::NOT_VISITED && wd.cost_bwd == PerWireData::NOT_VISITED)
             t.dirty_wires.push_back(wire);
         wd.pip_bwd = pip;
-        wd.visited_bwd = true;
         wd.cost_bwd = cost;
     }
 
     bool was_visited_fwd(int wire, float cost)
     {
-        return flat_wires.at(wire).visited_fwd && flat_wires.at(wire).cost_fwd <= cost;
+        return flat_wires.at(wire).cost_fwd != PerWireData::NOT_VISITED && flat_wires.at(wire).cost_fwd <= cost;
     }
     bool was_visited_bwd(int wire, float cost)
     {
-        return flat_wires.at(wire).visited_bwd && flat_wires.at(wire).cost_bwd <= cost;
+        return flat_wires.at(wire).cost_bwd != PerWireData::NOT_VISITED && flat_wires.at(wire).cost_bwd <= cost;
     }
 
     float get_arc_crit(NetInfo *net, store_index<PortRef> i)
@@ -934,7 +929,7 @@ struct Router2
                             continue;
                         }
                         auto &nwd = flat_wires.at(next_idx);
-                        if (nwd.unavailable)
+                        if (nwd.reserved_net == PerWireData::RESERVED_UNAVAILABLE)
                             continue;
                         // Reserved for another net
                         if (nwd.reserved_net != -1 && nwd.reserved_net != net->udata)
@@ -1011,7 +1006,7 @@ struct Router2
                             continue;
                         }
                         auto &nwd = flat_wires.at(next_idx);
-                        if (nwd.unavailable)
+                        if (nwd.reserved_net == PerWireData::RESERVED_UNAVAILABLE)
                             continue;
                         // Reserved for another net
                         if (nwd.reserved_net != -1 && nwd.reserved_net != net->udata)