Fix TSP when order locations are set (#503)

This PR fixes uninitialized depot pred/succ when order locations are
set.
There was also an issue when computing the distance cost with the
exclusive scan for the order location case. We are now using the correct
number of nodes for both cases.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Refactor**
* Simplified internal route copying mechanism by removing explicit
parameters.
* Adjusted sliding TSP local search algorithm to consider a different
set of orders during optimization.
  * Modified memory allocation strategy for routing computations.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: hlinsen

cpp/src/routing/local_search/sliding_tsp.cu

@@ -275,7 +275,7 @@ __global__ void execute_sliding_moves_tsp(
   s_route.copy_from(route);
   __syncthreads();
 
-  s_route.copy_to_tsp_route(sol.problem.order_info.depot_included);
+  s_route.copy_to_tsp_route();
 
   __shared__ i_t sh_overlaps;
 
@@ -471,7 +471,7 @@ void compute_cumulative_distances(solution_t<i_t, f_t, REQUEST>& sol,
                                 n_temp_storage_bytes,
                                 distances_ptr,
                                 distances_ptr,
-                                n_nodes + 1,
+                                n_nodes + 2,
                                 sol.sol_handle->get_stream());
 
   if (n_temp_storage_bytes > 0) {
@@ -484,7 +484,7 @@ void compute_cumulative_distances(solution_t<i_t, f_t, REQUEST>& sol,
                                 temp_storage_bytes,
                                 distances_ptr,
                                 distances_ptr,
-                                n_nodes + 1,
+                                n_nodes + 2,
                                 sol.sol_handle->get_stream());
 }
 
@@ -504,7 +504,7 @@ bool local_search_t<i_t, f_t, REQUEST>::perform_sliding_tsp(
   sol.compute_max_active();
   moved_regions_.resize(sol.get_n_routes() * sol.get_max_active_nodes_for_all_routes(),
                         sol.sol_handle->get_stream());
-  auto n_nodes              = sol.get_num_orders();
+  auto n_nodes              = sol.problem_ptr->order_info.get_num_depot_excluded_orders();
   size_t temp_storage_bytes = 0;
   resize_temp_storage<i_t, f_t, REQUEST>(sol, move_candidates, n_nodes, temp_storage_bytes);
 

cpp/src/routing/route/route.cuh

@@ -245,10 +245,11 @@ class route_t {
       return get_node(*n_nodes).time_dim.forward_feasible(this->vehicle_info());
     }
 
-    DI void copy_to_tsp_route(bool depot_included)
+    DI void copy_to_tsp_route()
     {
       dimensions.requests.tsp_requests.start = get_node(0).node_info();
       dimensions.requests.tsp_requests.end   = get_node(*n_nodes).node_info();
+
       for (i_t tid = threadIdx.x; tid < *n_nodes; tid += blockDim.x) {
         if (get_node(tid).node_info().is_depot()) { continue; }
         dimensions.requests.tsp_requests.pred[get_node(tid).node_info().node()] =
@@ -257,10 +258,10 @@ class route_t {
           get_node(tid + 1).node_info();
       }
 
-      if (depot_included) {
-        dimensions.requests.tsp_requests.pred[0] = get_node(*n_nodes - 1).node_info();
-        dimensions.requests.tsp_requests.succ[0] = get_node(1).node_info();
-      }
+      dimensions.requests.tsp_requests.pred[dimensions.requests.tsp_requests.end.node()] =
+        get_node(*n_nodes - 1).node_info();
+      dimensions.requests.tsp_requests.succ[dimensions.requests.tsp_requests.start.node()] =
+        get_node(1).node_info();
     }
 
     // insert a single node to the route