[FEA] PP prepare_inputs add autocast (#10502) (#11043)

Author: umiswing

paddlenlp/trainer/trainer.py

@@ -2568,7 +2568,8 @@ def training_pipeline_step(self, model: nn.Layer, inputs: Dict[str, Union[paddle
         # for v in self._pp_data_buffer[0].values():
         #     assert isinstance(v, paddle.Tensor), f"Only support tensor as pipeline mode input, got type {type(v)}"
 
-        inputs = model._prepare_pipeline_inputs_func(self._pp_data_buffer)
+        with self.autocast_smart_context_manager():
+            inputs = model._prepare_pipeline_inputs_func(self._pp_data_buffer)
         self._pp_data_buffer = []
 
         model.train()