2 files changed, 12 insertions, 2 deletions
diff --git a/common/nextpnr.cc b/common/nextpnr.cc
index ce2cef63..d2b887de 100644
--- a/common/nextpnr.cc
+++ b/common/nextpnr.cc
@@ -28,7 +28,15 @@ void IdString::initialize()
 {
     database_str_to_idx = new std::unordered_map<std::string, int>;
     database_idx_to_str = new std::vector<const std::string*>;
-    auto insert_rc = database_str_to_idx->insert({std::string(), 0});
+    initialize_add("", 0);
+    initialize_chip();
+}
+
+void IdString::initialize_add(const char *s, int idx)
+{
+    assert(database_str_to_idx->count(s) == 0);
+    assert(database_idx_to_str->size() == idx);
+    auto insert_rc = database_str_to_idx->insert({s, idx});
     database_idx_to_str->push_back(&insert_rc.first->first);
 }
 
diff --git a/common/nextpnr.h b/common/nextpnr.h
index dad6239f..fc14299d 100644
--- a/common/nextpnr.h
+++ b/common/nextpnr.h
@@ -48,7 +48,9 @@ struct IdString
     static std::unordered_map<std::string, int> *database_str_to_idx;
     static std::vector<const std::string*> *database_idx_to_str;
 
-    void initialize();
+    static void initialize();
+    static void initialize_chip();
+    static void initialize_add(const char *s, int idx);
 
     IdString() {}