fix bug of fp16 (#38838)

python/paddle/fluid/dygraph/layers.py

@@ -1279,8 +1279,36 @@ class Layer(object):
     def _obtain_parameters_buffers(self,
                                    destination=None,
                                    include_sublayers=True,
-                                   structured_name_prefix="",
-                                   include_non_persistable_buffer=False):
+                                   structured_name_prefix=""):
+        """
+        The difference from state_dict() is that state_dict_hook will not be called, 
+        but the original types of parameters and buffers will be maintained.
+        """
+        if destination is None:
+            destination = collections.OrderedDict()
+        for name, data in self._parameters.items():
+            if data is not None:
+                destination[structured_name_prefix + name] = data
+        for name, buffer in self._buffers.items():
+            if buffer is not None and name not in self._non_persistable_buffer_names_set:
+                destination[structured_name_prefix + name] = buffer
+
+        if include_sublayers:
+            for layer_name, layer_item in self._sub_layers.items():
+                if layer_item is not None:
+                    destination_temp = destination.copy()
+                    destination_temp.update(
+                        layer_item._obtain_parameters_buffers(
+                            destination_temp, include_sublayers,
+                            structured_name_prefix + layer_name + "."))
+                    destination = destination_temp
+        return destination
+
+    def _state_dict_impl(self,
+                         destination=None,
+                         include_sublayers=True,
+                         structured_name_prefix="",
+                         include_non_persistable_buffer=False):
         """
         Get all parameters and persistable buffers of current layer and its sub-layers. And set them into a dict
 
@@ -1313,16 +1341,6 @@ class Layer(object):
                             structured_name_prefix + layer_name + ".",
                             include_non_persistable_buffer))
                     destination = destination_temp
-        return destination
-
-    def _state_dict_impl(self,
-                         destination=None,
-                         include_sublayers=True,
-                         structured_name_prefix="",
-                         include_non_persistable_buffer=False):
-        destination = self._obtain_parameters_buffers(
-            destination, include_sublayers, structured_name_prefix,
-            include_non_persistable_buffer)
         for state_dict_hook in self._state_dict_hooks.values():
             hook_result = state_dict_hook(destination)
             if hook_result is not None: