[core] Raise warning on using prepare_model_for_int8_training (#483)

* raise warning on using older method

* Update src/peft/utils/other.py

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* quality

---------

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

src/peft/__init__.py

@@ -52,6 +52,7 @@
     bloom_model_postprocess_past_key_value,
     get_peft_model_state_dict,
     prepare_model_for_int8_training,
+    prepare_model_for_kbit_training,
     set_peft_model_state_dict,
     shift_tokens_right,
 )

src/peft/utils/__init__.py

@@ -27,6 +27,7 @@
     _set_trainable,
     bloom_model_postprocess_past_key_value,
     prepare_model_for_int8_training,
+    prepare_model_for_kbit_training,
     shift_tokens_right,
     transpose,
     _get_submodules,

src/peft/utils/other.py

@@ -14,6 +14,7 @@
 # limitations under the License.
 
 import copy
+import warnings
 
 import torch
 
@@ -32,7 +33,7 @@ def bloom_model_postprocess_past_key_value(past_key_values):
     return tuple(zip(keys, values))
 
 
-def prepare_model_for_int8_training(model, use_gradient_checkpointing=True):
+def prepare_model_for_kbit_training(model, use_gradient_checkpointing=True):
     r"""
     This method wraps the entire protocol for preparing a model before running a training. This includes:
         1- Cast the layernorm in fp32 2- making output embedding layer require grads 3- Add the upcasting of the lm
@@ -70,6 +71,15 @@ def make_inputs_require_grad(module, input, output):
     return model
 
 
+# For backward compatibility
+def prepare_model_for_int8_training(*args, **kwargs):
+    warnings.warn(
+        "prepare_model_for_int8_training is deprecated and will be removed in a future version. Use prepare_model_for_kbit_training instead.",
+        FutureWarning,
+    )
+    return prepare_model_for_kbit_training(*args, **kwargs)
+
+
 # copied from transformers.models.bart.modeling_bart
 def shift_tokens_right(input_ids: torch.Tensor, pad_token_id: int, decoder_start_token_id: int):
     """