RR Graph / Architecture Pin Side Consistency Check

libs/libarchfpga/src/switchblock_types.h

@@ -18,7 +18,8 @@ enum e_directionality {
 /**
  * @brief At the intersection of routing channels, left, right, top and bottom specify the x- and y-directed channels
  * while above and under specify the switch block wires one a layer above or below the current one. above and below
- * are only used for multi-layer FPGAs. 
+ * are only used for multi-layer FPGAs. Note that the order of 2D sides is important, as it corresponds to the bit 
+ * order in t_rr_node_data::dir_side_.sides.
  */
 enum e_side : unsigned char {
     TOP = 0,

libs/librrgraph/src/base/check_rr_graph.cpp

@@ -473,6 +473,8 @@ void check_rr_node(const RRGraphView& rr_graph,
 
     e_pin_type class_type = e_pin_type::OPEN;
     int class_num_pins = -1;
+    std::vector<e_side> rr_graph_sides;
+    std::vector<e_side> arch_side_vec;
     switch (rr_type) {
         case e_rr_type::SOURCE:
         case e_rr_type::SINK:
@@ -511,6 +513,19 @@ void check_rr_node(const RRGraphView& rr_graph,
                 VPR_FATAL_ERROR(VPR_ERROR_ROUTE,
                                 "in check_rr_node: inode %d (type %d) has a capacity of %d.\n", inode, rr_type, capacity);
             }
+            rr_graph_sides = rr_graph.node_sides(rr_node);
+            std::tie(std::ignore, std::ignore, arch_side_vec) = get_pin_coordinates(type, ptc_num, std::vector<e_side>(TOTAL_2D_SIDES.begin(), TOTAL_2D_SIDES.end()));
+            // sides in the architecture are a superset of the sides for a pin in RR Graph. We iterate over the sides stored
+            // in the RR Graph to ensure that all of them also exist in the architecture.   
+            for (size_t i = 0; i < rr_graph_sides.size(); i++) {
+                if (std::find(arch_side_vec.begin(), arch_side_vec.end(), rr_graph_sides[i]) == arch_side_vec.end()) {
+                    VPR_FATAL_ERROR(VPR_ERROR_ROUTE,
+                                "in check_rr_node: inode %d (type %d) has a different side '%s' in the RR graph and the architecture.\n", 
+                                inode, 
+                                rr_type, 
+                                TOTAL_2D_SIDE_STRINGS[rr_graph_sides[i]]);
+                }
+            }
             break;
 
         case e_rr_type::CHANX:

libs/librrgraph/src/base/rr_graph_storage.cpp

@@ -631,6 +631,17 @@ const std::string& t_rr_graph_storage::node_direction_string(RRNodeId id) const
     return CONST_DIRECTION_STRING[int_direction];
 }
 
+
+const std::vector<e_side> t_rr_graph_storage::node_sides(RRNodeId id) const {
+    std::vector<e_side> sides;
+    for (const e_side& side : TOTAL_2D_SIDES) {
+        if (is_node_on_specific_side(id, side)) {
+            sides.push_back(side);
+        }
+    }
+    return sides;
+}
+
 const char* t_rr_graph_storage::node_side_string(RRNodeId id) const {
     for (const e_side& side : TOTAL_2D_SIDES) {
         if (is_node_on_specific_side(id, side)) {
@@ -807,7 +818,7 @@ void t_rr_graph_storage::set_node_direction(RRNodeId id, Direction new_direction
 
 void t_rr_graph_storage::add_node_side(RRNodeId id, e_side new_side) {
     if (node_type(id) != e_rr_type::IPIN && node_type(id) != e_rr_type::OPIN) {
-        VTR_LOG_ERROR("Attempted to set RR node 'side' for non-channel type '%s'", node_type_string(id));
+        VTR_LOG_ERROR("Attempted to set RR node 'side' for non-pin type '%s'", node_type_string(id));
     }
     std::bitset<NUM_2D_SIDES> side_bits = node_storage_[id].dir_side_.sides;
     side_bits[size_t(new_side)] = true;

libs/librrgraph/src/base/rr_graph_storage.h

@@ -220,6 +220,9 @@ class t_rr_graph_storage {
             id, side);
     }
 
+    /** @brief Get the sides where the node locates on. */
+    const std::vector<e_side> node_sides(RRNodeId id) const;
+
     /* FIXME: This function should be DEPRECATED!
      * Developers can easily use the following codes with more flexibility
      *

libs/librrgraph/src/base/rr_graph_view.h

@@ -432,6 +432,11 @@ class RRGraphView {
         return node_storage_.is_node_on_specific_side(node, side);
     }
 
+    /** @brief Get the sides where the node locates on. */
+    inline const std::vector<e_side> node_sides(RRNodeId node) const {
+        return node_storage_.node_sides(node);
+    }
+
     /** @brief Return a string representing the side of a routing resource node. 
      */
     inline const char* node_side_string(RRNodeId node) const {

vpr/src/util/vpr_utils.cpp

@@ -1679,6 +1679,9 @@ RRNodeId get_pin_rr_node_id(const RRSpatialLookup& rr_spatial_lookup,
     std::tie(x_offset, y_offset, pin_sides) = get_pin_coordinates(physical_tile, pin_physical_num, std::vector<e_side>(TOTAL_2D_SIDES.begin(), TOTAL_2D_SIDES.end()));
     VTR_ASSERT(!x_offset.empty());
     RRNodeId node_id = RRNodeId::INVALID();
+    // Pin sides from get_pin_coordinates are those specified in the architecture. However, when
+    // adding pins to the RR Graph, not all sides may be included (depending on the block’s location).
+    // Therefore, we iterate over all sides to find a valid node id.
     for (int coord_idx = 0; coord_idx < (int)pin_sides.size(); coord_idx++) {
         node_id = rr_spatial_lookup.find_node(root_loc.layer_num,
                                               root_loc.x + x_offset[coord_idx],