Files
FastDeploy/fastdeploy/model_executor/models/paddleformers/causallm.py
T
jackyYang6 988e0bc338 [Feature] Add PaddleFormers fallback backend (#5999)
* feat(paddleformers): add dense text model fallback backend

* docs(paddleformers): add user guide and fix code review issues

* add fallback unit test

* precommit format

* fix pre-commit

* fix: address code review feedback

* docs: add PaddleFormers backend documentation (EN) and simplify installation

---------

Co-authored-by: Jiang-Jia-Jun <163579578+Jiang-Jia-Jun@users.noreply.github.com>
Co-authored-by: YuBaoku <49938469+EmmonsCurse@users.noreply.github.com>
2026-01-19 21:50:50 +08:00

72 lines
2.4 KiB
Python

"""
# Copyright (c) 2025 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
"""Causal LM Mixin for PaddleFormers models.
This mixin provides lm_head and compute_logits functionality.
The forward() method is implemented in PaddleFormersModelBase.
"""
from typing import TYPE_CHECKING
import paddle
from fastdeploy.model_executor.layers.lm_head import ParallelLMHead
if TYPE_CHECKING:
from fastdeploy.config import FDConfig
class CausalLMMixin:
"""Mixin class that provides causal LM functionality for PaddleFormers models.
This mixin only handles:
- lm_head initialization
- compute_logits (hidden_states -> logits)
The forward() method is inherited from PaddleFormersModelBase which computes
input_ids -> hidden_states.
This is a private mixin class and should NOT be instantiated directly.
Use PaddleFormersForCausalLM instead.
"""
def __init__(self, fd_config: "FDConfig", **kwargs):
super().__init__(fd_config, **kwargs)
self.ori_vocab_size = fd_config.model_config.ori_vocab_size
self.tie_word_embeddings = fd_config.model_config.tie_word_embeddings
with_bias = getattr(self.text_config, "use_bias", False) or getattr(self.text_config, "bias", False)
self.lm_head = ParallelLMHead(
fd_config=fd_config,
embedding_dim=self.text_config.hidden_size,
num_embeddings=self.text_config.vocab_size,
prefix="lm_head",
with_bias=with_bias,
)
def compute_logits(self, hidden_state, **kwargs):
"""Compute logits from hidden states using lm_head."""
logits = self.lm_head(hidden_state)
logits = logits.astype(paddle.float32)
logits[:, self.ori_vocab_size :] = -float("inf")
return logits
def set_state_dict(self, state_dict):
self.load_weights(state_dict.items())