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# This file was automatically generated from src/transformers/models/roberta/modular_roberta.py.
# Do NOT edit this file manually as any edits will be overwritten by the generation of
# the file from the modular. If any change should be done, please apply the change to the
# modular_roberta.py file directly. One of our CI enforces this.
# 🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨
# Copyright 2018 The Google AI Language Team Authors and The HuggingFace Inc. team.
# Copyright (c) 2018, NVIDIA CORPORATION. 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.
from collections.abc import Callable
import torch
import torch.nn as nn
from torch.nn import BCEWithLogitsLoss, CrossEntropyLoss, MSELoss
from ... import initialization as init
from ...activations import ACT2FN, gelu
from ...cache_utils import Cache, DynamicCache, EncoderDecoderCache
from ...generation import GenerationMixin
from ...masking_utils import create_bidirectional_mask, create_causal_mask
from ...modeling_layers import GradientCheckpointingLayer
from ...modeling_outputs import (
BaseModelOutputWithPastAndCrossAttentions,
BaseModelOutputWithPoolingAndCrossAttentions,
CausalLMOutputWithCrossAttentions,
MaskedLMOutput,
MultipleChoiceModelOutput,
QuestionAnsweringModelOutput,
SequenceClassifierOutput,
TokenClassifierOutput,
)
from ...modeling_utils import ALL_ATTENTION_FUNCTIONS, PreTrainedModel
from ...processing_utils import Unpack
from ...pytorch_utils import apply_chunking_to_forward
from ...utils import TransformersKwargs, auto_docstring, logging
from ...utils.generic import can_return_tuple, check_model_inputs
from .configuration_roberta import RobertaConfig
logger = logging.get_logger(__name__)
class RobertaEmbeddings(nn.Module):
"""Construct the embeddings from word, position and token_type embeddings."""
def __init__(self, config):
super().__init__()
self.word_embeddings = nn.Embedding(config.vocab_size, config.hidden_size, padding_idx=config.pad_token_id)
self.token_type_embeddings = nn.Embedding(config.type_vocab_size, config.hidden_size)
self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.dropout = nn.Dropout(config.hidden_dropout_prob)
# position_ids (1, len position emb) is contiguous in memory and exported when serialized
self.register_buffer(
"position_ids", torch.arange(config.max_position_embeddings).expand((1, -1)), persistent=False
)
self.register_buffer(
"token_type_ids", torch.zeros(self.position_ids.size(), dtype=torch.long), persistent=False
)
self.padding_idx = config.pad_token_id
self.position_embeddings = nn.Embedding(
config.max_position_embeddings, config.hidden_size, padding_idx=self.padding_idx
)
def forward(
self,
input_ids: torch.LongTensor | None = None,
token_type_ids: torch.LongTensor | None = None,
position_ids: torch.LongTensor | None = None,
inputs_embeds: torch.FloatTensor | None = None,
past_key_values_length: int = 0,
) -> torch.Tensor:
if position_ids is None:
if input_ids is not None:
# Create the position ids from the input token ids. Any padded tokens remain padded.
position_ids = self.create_position_ids_from_input_ids(
input_ids, self.padding_idx, past_key_values_length
)
else:
position_ids = self.create_position_ids_from_inputs_embeds(inputs_embeds, self.padding_idx)
if input_ids is not None:
input_shape = input_ids.size()
else:
input_shape = inputs_embeds.size()[:-1]
batch_size, seq_length = input_shape
# Setting the token_type_ids to the registered buffer in constructor where it is all zeros, which usually occurs
# when its auto-generated, registered buffer helps users when tracing the model without passing token_type_ids, solves
# issue #5664
if token_type_ids is None:
if hasattr(self, "token_type_ids"):
# NOTE: We assume either pos ids to have bsz == 1 (broadcastable) or bsz == effective bsz (input_shape[0])
buffered_token_type_ids = self.token_type_ids.expand(position_ids.shape[0], -1)
buffered_token_type_ids = torch.gather(buffered_token_type_ids, dim=1, index=position_ids)
token_type_ids = buffered_token_type_ids.expand(batch_size, seq_length)
else:
token_type_ids = torch.zeros(input_shape, dtype=torch.long, device=self.position_ids.device)
if inputs_embeds is None:
inputs_embeds = self.word_embeddings(input_ids)
token_type_embeddings = self.token_type_embeddings(token_type_ids)
embeddings = inputs_embeds + token_type_embeddings
position_embeddings = self.position_embeddings(position_ids)
embeddings = embeddings + position_embeddings
embeddings = self.LayerNorm(embeddings)
embeddings = self.dropout(embeddings)
return embeddings
@staticmethod
def create_position_ids_from_inputs_embeds(inputs_embeds, padding_idx):
"""
We are provided embeddings directly. We cannot infer which are padded so just generate sequential position ids.
Args:
inputs_embeds: torch.Tensor
Returns: torch.Tensor
"""
input_shape = inputs_embeds.size()[:-1]
sequence_length = input_shape[1]
position_ids = torch.arange(
padding_idx + 1, sequence_length + padding_idx + 1, dtype=torch.long, device=inputs_embeds.device
)
return position_ids.unsqueeze(0).expand(input_shape)
@staticmethod
def create_position_ids_from_input_ids(input_ids, padding_idx, past_key_values_length=0):
"""
Replace non-padding symbols with their position numbers. Position numbers begin at padding_idx+1. Padding symbols
are ignored. This is modified from fairseq's `utils.make_positions`.
Args:
x: torch.Tensor x:
Returns: torch.Tensor
"""
# The series of casts and type-conversions here are carefully balanced to both work with ONNX export and XLA.
mask = input_ids.ne(padding_idx).int()
incremental_indices = (torch.cumsum(mask, dim=1).type_as(mask) + past_key_values_length) * mask
return incremental_indices.long() + padding_idx
def eager_attention_forward(
module: nn.Module,
query: torch.Tensor,
key: torch.Tensor,
value: torch.Tensor,
attention_mask: torch.Tensor | None,
scaling: float | None = None,
dropout: float = 0.0,
**kwargs: Unpack[TransformersKwargs],
):
if scaling is None:
scaling = query.size(-1) ** -0.5
# Take the dot product between "query" and "key" to get the raw attention scores.
attn_weights = torch.matmul(query, key.transpose(2, 3)) * scaling
if attention_mask is not None:
attention_mask = attention_mask[:, :, :, : key.shape[-2]]
attn_weights = attn_weights + attention_mask
attn_weights = nn.functional.softmax(attn_weights, dim=-1)
attn_weights = nn.functional.dropout(attn_weights, p=dropout, training=module.training)
attn_output = torch.matmul(attn_weights, value)
attn_output = attn_output.transpose(1, 2).contiguous()
return attn_output, attn_weights
class RobertaSelfAttention(nn.Module):
def __init__(self, config, is_causal=False, layer_idx=None):
super().__init__()
if config.hidden_size % config.num_attention_heads != 0 and not hasattr(config, "embedding_size"):
raise ValueError(
f"The hidden size ({config.hidden_size}) is not a multiple of the number of attention "
f"heads ({config.num_attention_heads})"
)
self.config = config
self.num_attention_heads = config.num_attention_heads
self.attention_head_size = int(config.hidden_size / config.num_attention_heads)
self.all_head_size = self.num_attention_heads * self.attention_head_size
self.scaling = self.attention_head_size**-0.5
self.query = nn.Linear(config.hidden_size, self.all_head_size)
self.key = nn.Linear(config.hidden_size, self.all_head_size)
self.value = nn.Linear(config.hidden_size, self.all_head_size)
self.dropout = nn.Dropout(config.attention_probs_dropout_prob)
self.is_decoder = config.is_decoder
self.is_causal = is_causal
self.layer_idx = layer_idx
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: torch.FloatTensor | None = None,
past_key_values: Cache | None = None,
cache_position: torch.Tensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor]:
input_shape = hidden_states.shape[:-1]
hidden_shape = (*input_shape, -1, self.attention_head_size)
# get all proj
query_layer = self.query(hidden_states).view(*hidden_shape).transpose(1, 2)
key_layer = self.key(hidden_states).view(*hidden_shape).transpose(1, 2)
value_layer = self.value(hidden_states).view(*hidden_shape).transpose(1, 2)
if past_key_values is not None:
# decoder-only roberta can have a simple dynamic cache for example
current_past_key_values = past_key_values
if isinstance(past_key_values, EncoderDecoderCache):
current_past_key_values = past_key_values.self_attention_cache
# save all key/value_layer to cache to be re-used for fast auto-regressive generation
key_layer, value_layer = current_past_key_values.update(
key_layer,
value_layer,
self.layer_idx,
{"cache_position": cache_position},
)
attention_interface: Callable = ALL_ATTENTION_FUNCTIONS.get_interface(
self.config._attn_implementation, eager_attention_forward
)
attn_output, attn_weights = attention_interface(
self,
query_layer,
key_layer,
value_layer,
attention_mask,
dropout=0.0 if not self.training else self.dropout.p,
scaling=self.scaling,
**kwargs,
)
attn_output = attn_output.reshape(*input_shape, -1).contiguous()
return attn_output, attn_weights
class RobertaCrossAttention(nn.Module):
def __init__(self, config, is_causal=False, layer_idx=None):
super().__init__()
if config.hidden_size % config.num_attention_heads != 0 and not hasattr(config, "embedding_size"):
raise ValueError(
f"The hidden size ({config.hidden_size}) is not a multiple of the number of attention "
f"heads ({config.num_attention_heads})"
)
self.config = config
self.num_attention_heads = config.num_attention_heads
self.attention_head_size = int(config.hidden_size / config.num_attention_heads)
self.all_head_size = self.num_attention_heads * self.attention_head_size
self.scaling = self.attention_head_size**-0.5
self.query = nn.Linear(config.hidden_size, self.all_head_size)
self.key = nn.Linear(config.hidden_size, self.all_head_size)
self.value = nn.Linear(config.hidden_size, self.all_head_size)
self.dropout = nn.Dropout(config.attention_probs_dropout_prob)
self.is_causal = is_causal
self.layer_idx = layer_idx
def forward(
self,
hidden_states: torch.Tensor,
encoder_hidden_states: torch.FloatTensor | None = None,
attention_mask: torch.FloatTensor | None = None,
past_key_values: EncoderDecoderCache | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor]:
# determine input shapes
bsz, tgt_len = hidden_states.shape[:-1]
src_len = encoder_hidden_states.shape[1]
q_input_shape = (bsz, tgt_len, -1, self.attention_head_size)
kv_input_shape = (bsz, src_len, -1, self.attention_head_size)
# get query proj
query_layer = self.query(hidden_states).view(*q_input_shape).transpose(1, 2)
is_updated = past_key_values.is_updated.get(self.layer_idx) if past_key_values is not None else False
if past_key_values is not None and is_updated:
# reuse k,v, cross_attentions
key_layer = past_key_values.cross_attention_cache.layers[self.layer_idx].keys
value_layer = past_key_values.cross_attention_cache.layers[self.layer_idx].values
else:
key_layer = self.key(encoder_hidden_states).view(*kv_input_shape).transpose(1, 2)
value_layer = self.value(encoder_hidden_states).view(*kv_input_shape).transpose(1, 2)
if past_key_values is not None:
# save all states to the cache
key_layer, value_layer = past_key_values.cross_attention_cache.update(
key_layer, value_layer, self.layer_idx
)
# set flag that curr layer for cross-attn is already updated so we can re-use in subsequent calls
past_key_values.is_updated[self.layer_idx] = True
attention_interface: Callable = ALL_ATTENTION_FUNCTIONS.get_interface(
self.config._attn_implementation, eager_attention_forward
)
attn_output, attn_weights = attention_interface(
self,
query_layer,
key_layer,
value_layer,
attention_mask,
dropout=0.0 if not self.training else self.dropout.p,
scaling=self.scaling,
**kwargs,
)
attn_output = attn_output.reshape(bsz, tgt_len, -1).contiguous()
return attn_output, attn_weights
class RobertaSelfOutput(nn.Module):
def __init__(self, config):
super().__init__()
self.dense = nn.Linear(config.hidden_size, config.hidden_size)
self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.dropout = nn.Dropout(config.hidden_dropout_prob)
def forward(self, hidden_states: torch.Tensor, input_tensor: torch.Tensor) -> torch.Tensor:
hidden_states = self.dense(hidden_states)
hidden_states = self.dropout(hidden_states)
hidden_states = self.LayerNorm(hidden_states + input_tensor)
return hidden_states
class RobertaAttention(nn.Module):
def __init__(self, config, is_causal=False, layer_idx=None, is_cross_attention=False):
super().__init__()
self.is_cross_attention = is_cross_attention
attention_class = RobertaCrossAttention if is_cross_attention else RobertaSelfAttention
self.self = attention_class(config, is_causal=is_causal, layer_idx=layer_idx)
self.output = RobertaSelfOutput(config)
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: torch.FloatTensor | None = None,
encoder_hidden_states: torch.FloatTensor | None = None,
encoder_attention_mask: torch.FloatTensor | None = None,
past_key_values: Cache | None = None,
cache_position: torch.Tensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor]:
attention_mask = attention_mask if not self.is_cross_attention else encoder_attention_mask
attention_output, attn_weights = self.self(
hidden_states,
encoder_hidden_states=encoder_hidden_states,
attention_mask=attention_mask,
past_key_values=past_key_values,
cache_position=cache_position,
**kwargs,
)
attention_output = self.output(attention_output, hidden_states)
return attention_output, attn_weights
class RobertaIntermediate(nn.Module):
def __init__(self, config):
super().__init__()
self.dense = nn.Linear(config.hidden_size, config.intermediate_size)
if isinstance(config.hidden_act, str):
self.intermediate_act_fn = ACT2FN[config.hidden_act]
else:
self.intermediate_act_fn = config.hidden_act
def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
hidden_states = self.dense(hidden_states)
hidden_states = self.intermediate_act_fn(hidden_states)
return hidden_states
class RobertaOutput(nn.Module):
def __init__(self, config):
super().__init__()
self.dense = nn.Linear(config.intermediate_size, config.hidden_size)
self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.dropout = nn.Dropout(config.hidden_dropout_prob)
def forward(self, hidden_states: torch.Tensor, input_tensor: torch.Tensor) -> torch.Tensor:
hidden_states = self.dense(hidden_states)
hidden_states = self.dropout(hidden_states)
hidden_states = self.LayerNorm(hidden_states + input_tensor)
return hidden_states
class RobertaLayer(GradientCheckpointingLayer):
def __init__(self, config, layer_idx=None):
super().__init__()
self.chunk_size_feed_forward = config.chunk_size_feed_forward
self.seq_len_dim = 1
self.attention = RobertaAttention(config, is_causal=config.is_decoder, layer_idx=layer_idx)
self.is_decoder = config.is_decoder
self.add_cross_attention = config.add_cross_attention
if self.add_cross_attention:
if not self.is_decoder:
raise ValueError(f"{self} should be used as a decoder model if cross attention is added")
self.crossattention = RobertaAttention(
config,
is_causal=False,
layer_idx=layer_idx,
is_cross_attention=True,
)
self.intermediate = RobertaIntermediate(config)
self.output = RobertaOutput(config)
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: torch.FloatTensor | None = None,
encoder_hidden_states: torch.FloatTensor | None = None,
encoder_attention_mask: torch.FloatTensor | None = None,
past_key_values: Cache | None = None,
cache_position: torch.Tensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor]:
self_attention_output, _ = self.attention(
hidden_states,
attention_mask,
past_key_values=past_key_values,
cache_position=cache_position,
**kwargs,
)
attention_output = self_attention_output
if self.is_decoder and encoder_hidden_states is not None:
if not hasattr(self, "crossattention"):
raise ValueError(
f"If `encoder_hidden_states` are passed, {self} has to be instantiated with cross-attention layers"
" by setting `config.add_cross_attention=True`"
)
cross_attention_output, _ = self.crossattention(
self_attention_output,
None, # attention_mask
encoder_hidden_states,
encoder_attention_mask,
past_key_values=past_key_values,
**kwargs,
)
attention_output = cross_attention_output
layer_output = apply_chunking_to_forward(
self.feed_forward_chunk, self.chunk_size_feed_forward, self.seq_len_dim, attention_output
)
return layer_output
def feed_forward_chunk(self, attention_output):
intermediate_output = self.intermediate(attention_output)
layer_output = self.output(intermediate_output, attention_output)
return layer_output
@auto_docstring
class RobertaPreTrainedModel(PreTrainedModel):
config_class = RobertaConfig
base_model_prefix = "roberta"
supports_gradient_checkpointing = True
_supports_flash_attn = True
_supports_sdpa = True
_supports_flex_attn = True
_supports_attention_backend = True
_can_record_outputs = {
"hidden_states": RobertaLayer,
"attentions": RobertaSelfAttention,
"cross_attentions": RobertaCrossAttention,
}
@torch.no_grad()
def _init_weights(self, module):
"""Initialize the weights"""
super()._init_weights(module)
if isinstance(module, RobertaLMHead):
init.zeros_(module.bias)
elif isinstance(module, RobertaEmbeddings):
init.copy_(module.position_ids, torch.arange(module.position_ids.shape[-1]).expand((1, -1)))
init.zeros_(module.token_type_ids)
class RobertaEncoder(nn.Module):
def __init__(self, config):
super().__init__()
self.config = config
self.layer = nn.ModuleList([RobertaLayer(config, layer_idx=i) for i in range(config.num_hidden_layers)])
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: torch.FloatTensor | None = None,
encoder_hidden_states: torch.FloatTensor | None = None,
encoder_attention_mask: torch.FloatTensor | None = None,
past_key_values: Cache | None = None,
use_cache: bool | None = None,
cache_position: torch.Tensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor] | BaseModelOutputWithPastAndCrossAttentions:
for i, layer_module in enumerate(self.layer):
hidden_states = layer_module(
hidden_states,
attention_mask,
encoder_hidden_states, # as a positional argument for gradient checkpointing
encoder_attention_mask=encoder_attention_mask,
past_key_values=past_key_values,
cache_position=cache_position,
**kwargs,
)
return BaseModelOutputWithPastAndCrossAttentions(
last_hidden_state=hidden_states,
past_key_values=past_key_values if use_cache else None,
)
class RobertaPooler(nn.Module):
def __init__(self, config):
super().__init__()
self.dense = nn.Linear(config.hidden_size, config.hidden_size)
self.activation = nn.Tanh()
def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
# We "pool" the model by simply taking the hidden state corresponding
# to the first token.
first_token_tensor = hidden_states[:, 0]
pooled_output = self.dense(first_token_tensor)
pooled_output = self.activation(pooled_output)
return pooled_output
@auto_docstring(
custom_intro="""
The model can behave as an encoder (with only self-attention) as well as a decoder, in which case a layer of
cross-attention is added between the self-attention layers, following the architecture described in [Attention is
all you need](https://huggingface.co/papers/1706.03762) by Ashish Vaswani, Noam Shazeer, Niki Parmar, Jakob Uszkoreit,
Llion Jones, Aidan N. Gomez, Lukasz Kaiser and Illia Polosukhin.
To behave as an decoder the model needs to be initialized with the `is_decoder` argument of the configuration set
to `True`. To be used in a Seq2Seq model, the model needs to initialized with both `is_decoder` argument and
`add_cross_attention` set to `True`; an `encoder_hidden_states` is then expected as an input to the forward pass.
"""
)
class RobertaModel(RobertaPreTrainedModel):
_no_split_modules = ["RobertaEmbeddings", "RobertaLayer"]
def __init__(self, config, add_pooling_layer=True):
r"""
add_pooling_layer (bool, *optional*, defaults to `True`):
Whether to add a pooling layer
"""
super().__init__(config)
self.config = config
self.gradient_checkpointing = False
self.embeddings = RobertaEmbeddings(config)
self.encoder = RobertaEncoder(config)
self.pooler = RobertaPooler(config) if add_pooling_layer else None
# Initialize weights and apply final processing
self.post_init()
def get_input_embeddings(self):
return self.embeddings.word_embeddings
def set_input_embeddings(self, value):
self.embeddings.word_embeddings = value
@check_model_inputs
@auto_docstring
def forward(
self,
input_ids: torch.Tensor | None = None,
attention_mask: torch.Tensor | None = None,
token_type_ids: torch.Tensor | None = None,
position_ids: torch.Tensor | None = None,
inputs_embeds: torch.Tensor | None = None,
encoder_hidden_states: torch.Tensor | None = None,
encoder_attention_mask: torch.Tensor | None = None,
past_key_values: Cache | None = None,
use_cache: bool | None = None,
cache_position: torch.Tensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor] | BaseModelOutputWithPoolingAndCrossAttentions:
if self.config.is_decoder:
use_cache = use_cache if use_cache is not None else self.config.use_cache
else:
use_cache = False
if use_cache and past_key_values is None:
past_key_values = (
EncoderDecoderCache(DynamicCache(config=self.config), DynamicCache(config=self.config))
if encoder_hidden_states is not None or self.config.is_encoder_decoder
else DynamicCache(config=self.config)
)
if (input_ids is None) ^ (inputs_embeds is not None):
raise ValueError("You must specify exactly one of input_ids or inputs_embeds")
if input_ids is not None:
device = input_ids.device
seq_length = input_ids.shape[1]
else:
device = inputs_embeds.device
seq_length = inputs_embeds.shape[1]
past_key_values_length = past_key_values.get_seq_length() if past_key_values is not None else 0
if cache_position is None:
cache_position = torch.arange(past_key_values_length, past_key_values_length + seq_length, device=device)
embedding_output = self.embeddings(
input_ids=input_ids,
position_ids=position_ids,
token_type_ids=token_type_ids,
inputs_embeds=inputs_embeds,
past_key_values_length=past_key_values_length,
)
attention_mask, encoder_attention_mask = self._create_attention_masks(
attention_mask=attention_mask,
encoder_attention_mask=encoder_attention_mask,
embedding_output=embedding_output,
encoder_hidden_states=encoder_hidden_states,
cache_position=cache_position,
past_key_values=past_key_values,
)
encoder_outputs = self.encoder(
embedding_output,
attention_mask=attention_mask,
encoder_hidden_states=encoder_hidden_states,
encoder_attention_mask=encoder_attention_mask,
past_key_values=past_key_values,
use_cache=use_cache,
cache_position=cache_position,
position_ids=position_ids,
**kwargs,
)
sequence_output = encoder_outputs.last_hidden_state
pooled_output = self.pooler(sequence_output) if self.pooler is not None else None
return BaseModelOutputWithPoolingAndCrossAttentions(
last_hidden_state=sequence_output,
pooler_output=pooled_output,
past_key_values=encoder_outputs.past_key_values,
)
def _create_attention_masks(
self,
attention_mask,
encoder_attention_mask,
embedding_output,
encoder_hidden_states,
cache_position,
past_key_values,
):
if self.config.is_decoder:
attention_mask = create_causal_mask(
config=self.config,
input_embeds=embedding_output,
attention_mask=attention_mask,
cache_position=cache_position,
past_key_values=past_key_values,
)
else:
attention_mask = create_bidirectional_mask(
config=self.config,
input_embeds=embedding_output,
attention_mask=attention_mask,
)
if encoder_attention_mask is not None:
encoder_attention_mask = create_bidirectional_mask(
config=self.config,
input_embeds=embedding_output,
attention_mask=encoder_attention_mask,
encoder_hidden_states=encoder_hidden_states,
)
return attention_mask, encoder_attention_mask
@auto_docstring(
custom_intro="""
RoBERTa Model with a `language modeling` head on top for CLM fine-tuning.
"""
)
class RobertaForCausalLM(RobertaPreTrainedModel, GenerationMixin):
_tied_weights_keys = {
"lm_head.decoder.weight": "roberta.embeddings.word_embeddings.weight",
"lm_head.decoder.bias": "lm_head.bias",
}
def __init__(self, config):
super().__init__(config)
if not config.is_decoder:
logger.warning("If you want to use `RobertaLMHeadModel` as a standalone, add `is_decoder=True.`")
self.roberta = RobertaModel(config, add_pooling_layer=False)
self.lm_head = RobertaLMHead(config)
# Initialize weights and apply final processing
self.post_init()
def get_output_embeddings(self):
return self.lm_head.decoder
def set_output_embeddings(self, new_embeddings):
self.lm_head.decoder = new_embeddings
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: torch.LongTensor | None = None,
attention_mask: torch.FloatTensor | None = None,
token_type_ids: torch.LongTensor | None = None,
position_ids: torch.LongTensor | None = None,
inputs_embeds: torch.FloatTensor | None = None,
encoder_hidden_states: torch.FloatTensor | None = None,
encoder_attention_mask: torch.FloatTensor | None = None,
labels: torch.LongTensor | None = None,
past_key_values: tuple[tuple[torch.FloatTensor]] | None = None,
use_cache: bool | None = None,
cache_position: torch.Tensor | None = None,
logits_to_keep: int | torch.Tensor = 0,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor] | CausalLMOutputWithCrossAttentions:
r"""
token_type_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
Segment token indices to indicate first and second portions of the inputs. Indices are selected in `[0,1]`:
- 0 corresponds to a *sentence A* token,
- 1 corresponds to a *sentence B* token.
This parameter can only be used when the model is initialized with `type_vocab_size` parameter with value
>= 2. All the value in this tensor should be always < type_vocab_size.
[What are token type IDs?](../glossary#token-type-ids)
labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
Labels for computing the left-to-right language modeling loss (next word prediction). Indices should be in
`[-100, 0, ..., config.vocab_size]` (see `input_ids` docstring) Tokens with indices set to `-100` are
ignored (masked), the loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`
Example:
```python
>>> from transformers import AutoTokenizer, RobertaForCausalLM, AutoConfig
>>> import torch
>>> tokenizer = AutoTokenizer.from_pretrained("FacebookAI/roberta-base")
>>> config = AutoConfig.from_pretrained("FacebookAI/roberta-base")
>>> config.is_decoder = True
>>> model = RobertaForCausalLM.from_pretrained("FacebookAI/roberta-base", config=config)
>>> inputs = tokenizer("Hello, my dog is cute", return_tensors="pt")
>>> outputs = model(**inputs)
>>> prediction_logits = outputs.logits
```"""
if labels is not None:
use_cache = False
outputs: BaseModelOutputWithPoolingAndCrossAttentions = self.roberta(
input_ids,
attention_mask=attention_mask,
token_type_ids=token_type_ids,
position_ids=position_ids,
inputs_embeds=inputs_embeds,
encoder_hidden_states=encoder_hidden_states,
encoder_attention_mask=encoder_attention_mask,
past_key_values=past_key_values,
use_cache=use_cache,
cache_position=cache_position,
return_dict=True,
**kwargs,
)
hidden_states = outputs.last_hidden_state
# Only compute necessary logits, and do not upcast them to float if we are not computing the loss
slice_indices = slice(-logits_to_keep, None) if isinstance(logits_to_keep, int) else logits_to_keep
logits = self.lm_head(hidden_states[:, slice_indices, :])
loss = None
if labels is not None:
loss = self.loss_function(logits=logits, labels=labels, vocab_size=self.config.vocab_size, **kwargs)
return CausalLMOutputWithCrossAttentions(
loss=loss,
logits=logits,
past_key_values=outputs.past_key_values,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
cross_attentions=outputs.cross_attentions,
)
@auto_docstring
class RobertaForMaskedLM(RobertaPreTrainedModel):
_tied_weights_keys = {
"lm_head.decoder.weight": "roberta.embeddings.word_embeddings.weight",
"lm_head.decoder.bias": "lm_head.bias",
}
def __init__(self, config):
super().__init__(config)
if config.is_decoder:
logger.warning(
"If you want to use `RobertaForMaskedLM` make sure `config.is_decoder=False` for "
"bi-directional self-attention."
)
self.roberta = RobertaModel(config, add_pooling_layer=False)
self.lm_head = RobertaLMHead(config)
# Initialize weights and apply final processing
self.post_init()
def get_output_embeddings(self):
return self.lm_head.decoder
def set_output_embeddings(self, new_embeddings):
self.lm_head.decoder = new_embeddings
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: torch.LongTensor | None = None,
attention_mask: torch.FloatTensor | None = None,
token_type_ids: torch.LongTensor | None = None,
position_ids: torch.LongTensor | None = None,
inputs_embeds: torch.FloatTensor | None = None,
encoder_hidden_states: torch.FloatTensor | None = None,
encoder_attention_mask: torch.FloatTensor | None = None,
labels: torch.LongTensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor] | MaskedLMOutput:
r"""
token_type_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
Segment token indices to indicate first and second portions of the inputs. Indices are selected in `[0,1]`:
- 0 corresponds to a *sentence A* token,
- 1 corresponds to a *sentence B* token.
This parameter can only be used when the model is initialized with `type_vocab_size` parameter with value
>= 2. All the value in this tensor should be always < type_vocab_size.
[What are token type IDs?](../glossary#token-type-ids)
labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
Labels for computing the masked language modeling loss. Indices should be in `[-100, 0, ...,
config.vocab_size]` (see `input_ids` docstring) Tokens with indices set to `-100` are ignored (masked), the
loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`
"""
outputs = self.roberta(
input_ids,
attention_mask=attention_mask,
token_type_ids=token_type_ids,
position_ids=position_ids,
inputs_embeds=inputs_embeds,
encoder_hidden_states=encoder_hidden_states,
encoder_attention_mask=encoder_attention_mask,
return_dict=True,
**kwargs,
)
sequence_output = outputs[0]
prediction_scores = self.lm_head(sequence_output)
masked_lm_loss = None
if labels is not None:
# move labels to correct device
labels = labels.to(prediction_scores.device)
loss_fct = CrossEntropyLoss()
masked_lm_loss = loss_fct(prediction_scores.view(-1, self.config.vocab_size), labels.view(-1))
return MaskedLMOutput(
loss=masked_lm_loss,
logits=prediction_scores,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
class RobertaLMHead(nn.Module):
"""Roberta Head for masked language modeling."""
def __init__(self, config):
super().__init__()
self.dense = nn.Linear(config.hidden_size, config.hidden_size)
self.layer_norm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.decoder = nn.Linear(config.hidden_size, config.vocab_size)
self.bias = nn.Parameter(torch.zeros(config.vocab_size))
def forward(self, features, **kwargs):
x = self.dense(features)
x = gelu(x)
x = self.layer_norm(x)
# project back to size of vocabulary with bias
x = self.decoder(x)
return x
@auto_docstring(
custom_intro="""
RoBERTa Model transformer with a sequence classification/regression head on top (a linear layer on top of the
pooled output) e.g. for GLUE tasks.
"""
)
class RobertaForSequenceClassification(RobertaPreTrainedModel):
def __init__(self, config):
super().__init__(config)
self.num_labels = config.num_labels
self.config = config
self.roberta = RobertaModel(config, add_pooling_layer=False)
self.classifier = RobertaClassificationHead(config)
# Initialize weights and apply final processing
self.post_init()
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: torch.LongTensor | None = None,
attention_mask: torch.FloatTensor | None = None,
token_type_ids: torch.LongTensor | None = None,
position_ids: torch.LongTensor | None = None,
inputs_embeds: torch.FloatTensor | None = None,
labels: torch.LongTensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor] | SequenceClassifierOutput:
r"""
token_type_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
Segment token indices to indicate first and second portions of the inputs. Indices are selected in `[0,1]`:
- 0 corresponds to a *sentence A* token,
- 1 corresponds to a *sentence B* token.
This parameter can only be used when the model is initialized with `type_vocab_size` parameter with value
>= 2. All the value in this tensor should be always < type_vocab_size.
[What are token type IDs?](../glossary#token-type-ids)
labels (`torch.LongTensor` of shape `(batch_size,)`, *optional*):
Labels for computing the sequence classification/regression loss. Indices should be in `[0, ...,
config.num_labels - 1]`. If `config.num_labels == 1` a regression loss is computed (Mean-Square loss), If
`config.num_labels > 1` a classification loss is computed (Cross-Entropy).
"""
outputs = self.roberta(
input_ids,
attention_mask=attention_mask,
token_type_ids=token_type_ids,
position_ids=position_ids,
inputs_embeds=inputs_embeds,
return_dict=True,
**kwargs,
)
sequence_output = outputs[0]
logits = self.classifier(sequence_output)
loss = None
if labels is not None:
# move labels to correct device
labels = labels.to(logits.device)
if self.config.problem_type is None:
if self.num_labels == 1:
self.config.problem_type = "regression"
elif self.num_labels > 1 and (labels.dtype == torch.long or labels.dtype == torch.int):
self.config.problem_type = "single_label_classification"
else:
self.config.problem_type = "multi_label_classification"
if self.config.problem_type == "regression":
loss_fct = MSELoss()
if self.num_labels == 1:
loss = loss_fct(logits.squeeze(), labels.squeeze())
else:
loss = loss_fct(logits, labels)
elif self.config.problem_type == "single_label_classification":
loss_fct = CrossEntropyLoss()
loss = loss_fct(logits.view(-1, self.num_labels), labels.view(-1))
elif self.config.problem_type == "multi_label_classification":
loss_fct = BCEWithLogitsLoss()
loss = loss_fct(logits, labels)
return SequenceClassifierOutput(
loss=loss,
logits=logits,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
@auto_docstring
class RobertaForMultipleChoice(RobertaPreTrainedModel):
def __init__(self, config):
super().__init__(config)
self.roberta = RobertaModel(config)
self.dropout = nn.Dropout(config.hidden_dropout_prob)
self.classifier = nn.Linear(config.hidden_size, 1)
# Initialize weights and apply final processing
self.post_init()
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: torch.LongTensor | None = None,
token_type_ids: torch.LongTensor | None = None,
attention_mask: torch.FloatTensor | None = None,
labels: torch.LongTensor | None = None,
position_ids: torch.LongTensor | None = None,
inputs_embeds: torch.FloatTensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor] | MultipleChoiceModelOutput:
r"""
input_ids (`torch.LongTensor` of shape `(batch_size, num_choices, sequence_length)`):
Indices of input sequence tokens in the vocabulary.
Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and
[`PreTrainedTokenizer.__call__`] for details.
[What are input IDs?](../glossary#input-ids)
token_type_ids (`torch.LongTensor` of shape `(batch_size, num_choices, sequence_length)`, *optional*):
Segment token indices to indicate first and second portions of the inputs. Indices are selected in `[0,1]`:
- 0 corresponds to a *sentence A* token,
- 1 corresponds to a *sentence B* token.
This parameter can only be used when the model is initialized with `type_vocab_size` parameter with value
>= 2. All the value in this tensor should be always < type_vocab_size.
[What are token type IDs?](../glossary#token-type-ids)
labels (`torch.LongTensor` of shape `(batch_size,)`, *optional*):
Labels for computing the multiple choice classification loss. Indices should be in `[0, ...,
num_choices-1]` where `num_choices` is the size of the second dimension of the input tensors. (See
`input_ids` above)
position_ids (`torch.LongTensor` of shape `(batch_size, num_choices, sequence_length)`, *optional*):
Indices of positions of each input sequence tokens in the position embeddings. Selected in the range `[0,
config.max_position_embeddings - 1]`.
[What are position IDs?](../glossary#position-ids)
inputs_embeds (`torch.FloatTensor` of shape `(batch_size, num_choices, sequence_length, hidden_size)`, *optional*):
Optionally, instead of passing `input_ids` you can choose to directly pass an embedded representation. This
is useful if you want more control over how to convert `input_ids` indices into associated vectors than the
model's internal embedding lookup matrix.
"""
num_choices = input_ids.shape[1] if input_ids is not None else inputs_embeds.shape[1]
flat_input_ids = input_ids.view(-1, input_ids.size(-1)) if input_ids is not None else None
flat_position_ids = position_ids.view(-1, position_ids.size(-1)) if position_ids is not None else None
flat_token_type_ids = token_type_ids.view(-1, token_type_ids.size(-1)) if token_type_ids is not None else None
flat_attention_mask = attention_mask.view(-1, attention_mask.size(-1)) if attention_mask is not None else None
flat_inputs_embeds = (
inputs_embeds.view(-1, inputs_embeds.size(-2), inputs_embeds.size(-1))
if inputs_embeds is not None
else None
)
outputs = self.roberta(
flat_input_ids,
position_ids=flat_position_ids,
token_type_ids=flat_token_type_ids,
attention_mask=flat_attention_mask,
inputs_embeds=flat_inputs_embeds,
return_dict=True,
**kwargs,
)
pooled_output = outputs[1]
pooled_output = self.dropout(pooled_output)
logits = self.classifier(pooled_output)
reshaped_logits = logits.view(-1, num_choices)
loss = None
if labels is not None:
# move labels to correct device
labels = labels.to(reshaped_logits.device)
loss_fct = CrossEntropyLoss()
loss = loss_fct(reshaped_logits, labels)
return MultipleChoiceModelOutput(
loss=loss,
logits=reshaped_logits,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
@auto_docstring
class RobertaForTokenClassification(RobertaPreTrainedModel):
def __init__(self, config):
super().__init__(config)
self.num_labels = config.num_labels
self.roberta = RobertaModel(config, add_pooling_layer=False)
classifier_dropout = (
config.classifier_dropout if config.classifier_dropout is not None else config.hidden_dropout_prob
)
self.dropout = nn.Dropout(classifier_dropout)
self.classifier = nn.Linear(config.hidden_size, config.num_labels)
# Initialize weights and apply final processing
self.post_init()
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: torch.LongTensor | None = None,
attention_mask: torch.FloatTensor | None = None,
token_type_ids: torch.LongTensor | None = None,
position_ids: torch.LongTensor | None = None,
inputs_embeds: torch.FloatTensor | None = None,
labels: torch.LongTensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor] | TokenClassifierOutput:
r"""
token_type_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
Segment token indices to indicate first and second portions of the inputs. Indices are selected in `[0,1]`:
- 0 corresponds to a *sentence A* token,
- 1 corresponds to a *sentence B* token.
This parameter can only be used when the model is initialized with `type_vocab_size` parameter with value
>= 2. All the value in this tensor should be always < type_vocab_size.
[What are token type IDs?](../glossary#token-type-ids)
labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
Labels for computing the token classification loss. Indices should be in `[0, ..., config.num_labels - 1]`.
"""
outputs = self.roberta(
input_ids,
attention_mask=attention_mask,
token_type_ids=token_type_ids,
position_ids=position_ids,
inputs_embeds=inputs_embeds,
return_dict=True,
**kwargs,
)
sequence_output = outputs[0]
sequence_output = self.dropout(sequence_output)
logits = self.classifier(sequence_output)
loss = None
if labels is not None:
# move labels to correct device
labels = labels.to(logits.device)
loss_fct = CrossEntropyLoss()
loss = loss_fct(logits.view(-1, self.num_labels), labels.view(-1))
return TokenClassifierOutput(
loss=loss,
logits=logits,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
class RobertaClassificationHead(nn.Module):
"""Head for sentence-level classification tasks."""
def __init__(self, config):
super().__init__()
self.dense = nn.Linear(config.hidden_size, config.hidden_size)
classifier_dropout = (
config.classifier_dropout if config.classifier_dropout is not None else config.hidden_dropout_prob
)
self.dropout = nn.Dropout(classifier_dropout)
self.out_proj = nn.Linear(config.hidden_size, config.num_labels)
def forward(self, features, **kwargs):
x = features[:, 0, :] # take <s> token (equiv. to [CLS])
x = self.dropout(x)
x = self.dense(x)
x = torch.tanh(x)
x = self.dropout(x)
x = self.out_proj(x)
return x
@auto_docstring
class RobertaForQuestionAnswering(RobertaPreTrainedModel):
def __init__(self, config):
super().__init__(config)
self.num_labels = config.num_labels
self.roberta = RobertaModel(config, add_pooling_layer=False)
self.qa_outputs = nn.Linear(config.hidden_size, config.num_labels)
# Initialize weights and apply final processing
self.post_init()
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: torch.LongTensor | None = None,
attention_mask: torch.FloatTensor | None = None,
token_type_ids: torch.LongTensor | None = None,
position_ids: torch.LongTensor | None = None,
inputs_embeds: torch.FloatTensor | None = None,
start_positions: torch.LongTensor | None = None,
end_positions: torch.LongTensor | None = None,
**kwargs: Unpack[TransformersKwargs],
) -> tuple[torch.Tensor] | QuestionAnsweringModelOutput:
r"""
token_type_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
Segment token indices to indicate first and second portions of the inputs. Indices are selected in `[0,1]`:
- 0 corresponds to a *sentence A* token,
- 1 corresponds to a *sentence B* token.
This parameter can only be used when the model is initialized with `type_vocab_size` parameter with value
>= 2. All the value in this tensor should be always < type_vocab_size.
[What are token type IDs?](../glossary#token-type-ids)
"""
outputs = self.roberta(
input_ids,
attention_mask=attention_mask,
token_type_ids=token_type_ids,
position_ids=position_ids,
inputs_embeds=inputs_embeds,
return_dict=True,
**kwargs,
)
sequence_output = outputs[0]
logits = self.qa_outputs(sequence_output)
start_logits, end_logits = logits.split(1, dim=-1)
start_logits = start_logits.squeeze(-1).contiguous()
end_logits = end_logits.squeeze(-1).contiguous()
total_loss = None
if start_positions is not None and end_positions is not None:
# If we are on multi-GPU, split add a dimension
if len(start_positions.size()) > 1:
start_positions = start_positions.squeeze(-1)
if len(end_positions.size()) > 1:
end_positions = end_positions.squeeze(-1)
# sometimes the start/end positions are outside our model inputs, we ignore these terms
ignored_index = start_logits.size(1)
start_positions = start_positions.clamp(0, ignored_index)
end_positions = end_positions.clamp(0, ignored_index)
loss_fct = CrossEntropyLoss(ignore_index=ignored_index)
start_loss = loss_fct(start_logits, start_positions)
end_loss = loss_fct(end_logits, end_positions)
total_loss = (start_loss + end_loss) / 2
return QuestionAnsweringModelOutput(
loss=total_loss,
start_logits=start_logits,
end_logits=end_logits,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
__all__ = [
"RobertaForCausalLM",
"RobertaForMaskedLM",
"RobertaForMultipleChoice",
"RobertaForQuestionAnswering",
"RobertaForSequenceClassification",
"RobertaForTokenClassification",
"RobertaModel",
"RobertaPreTrainedModel",
]