mp_load_name(): Optimize for outer scope where locals == globals.

py/runtime.c

@@ -93,13 +93,15 @@ mp_obj_t mp_load_const_bytes(qstr qstr) {
 
 mp_obj_t mp_load_name(qstr qstr) {
     // logic: search locals, globals, builtins
-    DEBUG_OP_printf("load name %s\n", qstr_str(qstr));
-    mp_map_elem_t *elem = mp_map_lookup(map_locals, MP_OBJ_NEW_QSTR(qstr), MP_MAP_LOOKUP);
-    if (elem != NULL) {
-        return elem->value;
-    } else {
-        return mp_load_global(qstr);
+    DEBUG_OP_printf("load name %s\n", map_locals, qstr_str(qstr));
+    // If we're at the outer scope (locals == globals), dispatch to load_global right away
+    if (map_locals != map_globals) {
+        mp_map_elem_t *elem = mp_map_lookup(map_locals, MP_OBJ_NEW_QSTR(qstr), MP_MAP_LOOKUP);
+        if (elem != NULL) {
+            return elem->value;
+        }
     }
+    return mp_load_global(qstr);
 }
 
 mp_obj_t mp_load_global(qstr qstr) {