fix default parameter in avg_pool

frontend/guard_tracker.py

@@ -269,15 +269,15 @@ def record_function(self,
         pargs, pkwargs = self.as_node_args_kwargs(args, kwargs)
         if func == torch.nn.functional.avg_pool2d:
             # avg_pool2d only supports integer or tuple(with two int values) as inputs
-            if isinstance(pargs[1], tuple):
+            if len(pargs) >= 2 and isinstance(pargs[1], tuple):
                 for i in pargs[1]:
                     if isinstance(i, torch.fx.Node):
                         raise ValueError("cannot convert tensor in avg_pool2d")
-            if isinstance(args[1], tuple):
+            if len(args) >= 2 and isinstance(args[1], tuple):
                 for i in args[1]:
                     if torch.is_tensor(i):
                         raise ValueError("cannot convert tensor in avg_pool2d")
-            elif torch.is_tensor(args[1]):
+            elif len(args) >= 2 and torch.is_tensor(args[1]):
                 raise ValueError("cannot convert tensor in avg_pool2d")
         if func in fx_graph_inplace_functions:
             scalar = None