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Author: amin1377

libs/librrgraph/src/io/rr_graph_reader.cpp

@@ -87,6 +87,10 @@ void load_rr_file(RRGraphBuilder* rr_graph_builder,
         rr_graph_builder->set_tileable(true);
     }
 
+    // If Cap'n Proto is enabled, a unique ID is assigned to the schema used to serialize the RR graph.
+    // This ID is used to verify that the schema used to serialize the RR graph matches the
+    // schema being used to deserialize it.
+    // If Cap'n Proto is not enabled, the schema ID is 0 and no schema ID check is performed.
     unsigned long schema_file_id = 0;
 #ifdef VTR_ENABLE_CAPNPROTO
     ::capnp::Schema schema = ::capnp::Schema::from<ucap::RrGraph>();

libs/librrgraph/src/io/rr_graph_uxsdcxx_serializer.h

@@ -1730,8 +1730,11 @@ class RrGraphSerializer final : public uxsd::RrGraphBase<RrGraphContextTypes> {
      *   </xs:complexType>
      */
     inline void set_rr_graph_schema_file_id(unsigned long schema_file_id, void*& /*ctx*/) final {
-        // Only check if the schema file ID is not 0. If it is 0, it means capnproto is not enabled.
-        // Thus, we cannot check the schema file ID mismatch.
+        // Only check if schema_file_id_ (set when initializing the class) is not 0.
+        // If it is 0, it means Cap'n Proto is not enabled, so we cannot check for a schema file ID mismatch.
+        // This function is only called when the RR graph file being read contains a schema file ID.
+        // If it does not, this function is not called, and the RR graph can be read without performing
+        // the schema file ID check.
         if (schema_file_id_ != 0) {
             if (schema_file_id != schema_file_id_) {
                 report_error(

libs/librrgraph/src/io/rr_graph_writer.cpp

@@ -41,6 +41,10 @@ void write_rr_graph(RRGraphBuilder* rr_graph_builder,
                     const int route_verbosity,
                     bool is_flat) {
 
+    // If Cap'n Proto is enabled, a unique ID is assigned to the schema used to serialize the RR graph.
+    // This ID is used to verify that the schema used to serialize the RR graph matches the
+    // schema being used to deserialize it.
+    // If Cap'n Proto is not enabled, the schema ID is 0 and no schema ID check is performed.
     unsigned long schema_file_id = 0;
 #ifdef VTR_ENABLE_CAPNPROTO
     ::capnp::Schema schema = ::capnp::Schema::from<ucap::RrGraph>();