Add `inputs_embeds` support for `.generate()` with BLOOM models (#21430)

Add accepting `.generate()` calls with `inputs_embeds` on BLOOM models

src/transformers/models/bloom/modeling_bloom.py

@@ -842,6 +842,7 @@ class BloomForCausalLM(BloomPreTrainedModel):
         input_ids: torch.LongTensor,
         past_key_values: Optional[torch.Tensor] = None,
         attention_mask: Optional[torch.Tensor] = None,
+        inputs_embeds: Optional[torch.Tensor] = None,
         **kwargs
     ) -> dict:
         # only last token for input_ids if past is not None
@@ -852,12 +853,20 @@ class BloomForCausalLM(BloomPreTrainedModel):
             if past_key_values[0][0].shape[0] == input_ids.shape[0]:
                 past_key_values = self._convert_to_bloom_cache(past_key_values)
 
-        return {
-            "input_ids": input_ids,
+        # if `inputs_embeds` are passed, we only want to use them in the 1st generation step
+        if inputs_embeds is not None and past_key_values is None:
+            model_inputs = {"inputs_embeds": inputs_embeds}
+        else:
+            model_inputs = {"input_ids": input_ids}
+
+        model_inputs.update(
+            {
                 "past_key_values": past_key_values,
                 "use_cache": kwargs.get("use_cache"),
                 "attention_mask": attention_mask,
             }
+        )
+        return model_inputs
 
     @add_start_docstrings_to_model_forward(BLOOM_INPUTS_DOCSTRING)
     @add_code_sample_docstrings(