[VisionEncoderDecoder] Add gradient checkpointing (#18697)

* add first generation tutorial

* VisionEnocderDecoder gradient checkpointing

* remove generation

* add tests

tests/models/speech_encoder_decoder/test_modeling_speech_encoder_decoder.py

@@ -396,6 +396,28 @@ class EncoderDecoderMixin:
         input_ids_dict = self.prepare_config_and_inputs()
         self.check_encoder_decoder_model_generate(**input_ids_dict)
 
+    def test_training_gradient_checkpointing(self):
+        inputs_dict = self.prepare_config_and_inputs()
+        encoder_model, decoder_model = self.get_encoder_decoder_model(
+            inputs_dict["config"], inputs_dict["decoder_config"]
+        )
+
+        model = SpeechEncoderDecoderModel(encoder=encoder_model, decoder=decoder_model)
+        model.train()
+        model.gradient_checkpointing_enable()
+        model.config.decoder_start_token_id = 0
+        model.config.pad_token_id = 0
+
+        model_inputs = {
+            "attention_mask": inputs_dict["attention_mask"],
+            "labels": inputs_dict["labels"],
+            "decoder_input_ids": inputs_dict["decoder_input_ids"],
+        }
+        inputs = inputs_dict["input_features"] if "input_features" in inputs_dict else inputs_dict["input_values"]
+
+        loss = model(inputs, **model_inputs).loss
+        loss.backward()
+
     @slow
     def test_real_model_save_load_from_pretrained(self):
         model_2, inputs = self.get_pretrained_model_and_inputs()
@@ -590,6 +612,7 @@ class Wav2Vec2Speech2Text2(EncoderDecoderMixin, unittest.TestCase):
             "decoder_config": decoder_config,
             "decoder_input_ids": decoder_input_ids,
             "decoder_attention_mask": decoder_attention_mask,
+            "labels": decoder_input_ids,
         }
 
     # there are no published pretrained Speech2Text2ForCausalLM for now