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# coding=utf-8
# Copyright 2022 The OpenBMB Team and The HuggingFace Inc. team. 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.
""" PyTorch CPMAnt"""
import math
from typing import List, Optional, Tuple, Union
import torch
import torch.nn.functional as F
import torch.utils.checkpoint
from torch import nn
from torch.nn import CrossEntropyLoss
from ...activations import ACT2FN
from ...modeling_outputs import BaseModelOutputWithPast, CausalLMOutputWithPast
from ...modeling_utils import PreTrainedModel
from ...utils import add_code_sample_docstrings, add_start_docstrings, add_start_docstrings_to_model_forward, logging
from .configuration_cpmant import CpmAntConfig
logger = logging.get_logger(__name__)
_CHECKPOINT_FOR_DOC = "openbmb/cpm-ant-10b"
_CONFIG_FOR_DOC = "CpmAntConfig"
CPMANT_PRETRAINED_MODEL_ARCHIVE_LIST = [
"openbmb/cpm-ant-10b",
# See all CPMAnt models at https://huggingface.co/models?filter=cpmant
]
class CpmAntLayerNorm(nn.Module):
"""
We use Root Mean Square (RMS) Layer Normalization, please see https://arxiv.org/abs/1910.07467 for details."
"""
def __init__(self, config: CpmAntConfig):
super().__init__()
self.eps = config.eps
self.dim_norm = config.hidden_size
self.weight = nn.Parameter(torch.empty(config.hidden_size))
def forward(self, hidden_states: torch.Tensor):
"""
Args:
hidden_states (`torch.Tensor` of shape `(batch, seq_len, dim_in)`)
"""
if hidden_states.size(-1) != self.dim_norm:
raise AssertionError("hidden_states.size(-1) != self.dim_norm")
old_dtype = hidden_states.dtype
variance = hidden_states.to(torch.float32).pow(2).mean(dim=-1, keepdim=True)
hidden_states = (hidden_states * torch.rsqrt(variance + self.eps)).to(old_dtype) * self.weight
return hidden_states
class CpmAntAttention(nn.Module):
def __init__(self, config: CpmAntConfig):
super().__init__()
self.dim_model = config.hidden_size
self.num_heads = config.num_attention_heads
self.dim_head = config.dim_head
self.project_q = nn.Linear(self.dim_model, self.num_heads * self.dim_head, bias=False)
self.project_k = nn.Linear(self.dim_model, self.num_heads * self.dim_head, bias=False)
self.project_v = nn.Linear(self.dim_model, self.num_heads * self.dim_head, bias=False)
self.attention_out = nn.Linear(self.num_heads * self.dim_head, self.dim_model, bias=False)
self.softmax = torch.nn.Softmax(dim=-1)
if config.dropout_p is not None:
self.dropout = torch.nn.Dropout(p=config.dropout_p)
else:
self.dropout = None
def forward(
self,
hidden_q: torch.Tensor,
hidden_kv: torch.Tensor,
attention_mask: torch.BoolTensor,
position_bias: torch.Tensor,
output_attentions: Optional[bool] = False,
past_key_values: Optional[Tuple[torch.Tensor, torch.Tensor]] = None,
use_cache: Optional[bool] = None,
):
"""
Args:
hidden_q (`torch.Tensor`):
Input of transformer block(self-attention block). It can be the raw embedding of a batch of sequences.
hidden_kv (`torch.Tensor` of shape `(batch, len_k, dim_model)`)):
Tensor *key_value* and *query* of shape `(batch, len_k, dim_model)`
attention_mask (`torch.Tensor` of shape `(batch, len_seq, len_seq)`):
Avoid invalid areas to participate in the calculation of self-attention.
position_bias (`torch.Tensor` of shape `(batch, len_seq, len_seq)`):
Provide positional information to self-attention block.
output_attentions (`bool`, *optional*):
Whether or not to return the attentions tensors of all attention layers.
past_key_values (`Tuple[torch.Tensor, torch.Tensor]`, *optional*):
Cached past key and value projection states.
use_cache (`bool`, *optional*):
If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding
(see `past_key_values`).
"""
batch_size = hidden_q.size(0)
len_q = hidden_q.size(1)
len_k = hidden_kv.size(1)
query = self.project_q(hidden_q)
key = self.project_k(hidden_kv)
value = self.project_v(hidden_kv)
query = query.view(batch_size, len_q, self.num_heads, self.dim_head).permute(0, 2, 1, 3)
key = key.view(batch_size, len_k, self.num_heads, self.dim_head).permute(0, 2, 1, 3)
value = value.view(batch_size, len_k, self.num_heads, self.dim_head).permute(0, 2, 1, 3)
if past_key_values is not None:
key = torch.cat([past_key_values[0], key], dim=-2)
value = torch.cat([past_key_values[1], value], dim=-2)
len_k = key.size(-2)
# (batch_size, num_heads, len_q, dim_head) @ (batch_size, num_heads, dim_head, len_k) -> (batch_size, num_heads, len_q, len_k)
score = torch.matmul(query, key.transpose(-1, -2)) / math.sqrt(self.dim_head)
score = score + position_bias
score = torch.masked_fill(
score,
attention_mask.view(batch_size, 1, len_q, len_k) == torch.tensor(False),
torch.scalar_tensor(float("-inf"), device=score.device, dtype=score.dtype),
)
score = self.softmax(score)
score = torch.masked_fill(
score,
attention_mask.view(batch_size, 1, len_q, len_k) == torch.tensor(False),
torch.scalar_tensor(0, device=score.device, dtype=score.dtype),
)
if output_attentions:
attn_weights = score
else:
attn_weights = None
if self.dropout is not None:
score = self.dropout(score)
# (batch_size, num_heads, len_q, len_k) @ (batch_size, num_heads, len_k, dim_head) -> (batch_size, num_heads, len_q, dim_head)
score = torch.matmul(score, value)
score = score.view(batch_size, self.num_heads, len_q, self.dim_head).permute(0, 2, 1, 3)
score = score.contiguous().view(batch_size, len_q, self.num_heads * self.dim_head)
score = self.attention_out(score)
past_key_values = None
if use_cache:
past_key_values = (key, value)
return score, attn_weights, past_key_values
class CpmAntSelfAttentionBlock(nn.Module):
def __init__(self, config: CpmAntConfig):
super().__init__()
self.layernorm_before_attention = CpmAntLayerNorm(config)
self.self_attention = CpmAntAttention(config)
if config.dropout_p:
self.dropout = torch.nn.Dropout(config.dropout_p)
else:
self.dropout = None
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: torch.Tensor,
position_bias: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = False,
past_key_values: Optional[Tuple[torch.Tensor, torch.Tensor]] = None,
use_cache: Optional[bool] = None,
):
"""
Args:
hidden_states (`torch.Tensor` of shape `(batch, len_seq, dim_model)`):
Input of transformer block(self-attention block). It can be the raw embedding of a batch of sequences.
attention_mask (`torch.Tensor` of shape `(batch, len_seq, len_seq)`):
Avoid invalid areas to participate in the calculation of self-attention.
position_bias (`torch.Tensor` of shape `(batch, len_seq, len_seq)`):
Provide positional information to self-attention block.
output_attentions (`bool`, *optional*):
Whether or not to return the attentions tensors of all attention layers.
past_key_values (`Tuple(torch.FloatTensor)`, *optional*):
Cached past key and value projection states.
use_cache (`bool`, *optional*):
If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding
(see `past_key_values`).
"""
outputs = self.layernorm_before_attention(hidden_states)
outputs = self.self_attention(
outputs, outputs, attention_mask, position_bias, output_attentions, past_key_values, use_cache
)
outputs, attn_weights, current_key_value = outputs
if self.dropout is not None:
outputs = self.dropout(outputs)
hidden_states = hidden_states + outputs
return hidden_states, attn_weights, current_key_value
class CpmAntDenseGatedACT(nn.Module):
def __init__(self, config: CpmAntConfig):
super().__init__()
self.w_0 = nn.Linear(config.hidden_size, config.dim_ff, bias=False)
self.w_1 = nn.Linear(config.hidden_size, config.dim_ff, bias=False)
self.act = torch.nn.GELU()
def forward(self, hidden_states: torch.Tensor):
"""Transform an input tensor from one feature space to another via a nonlinear operation
Args:
hidden_states (`torch.Tensor` of shape `(batch, seq_len, dim_in)`)
"""
gate_score = self.act(self.w_0(hidden_states))
hidden_states = self.w_1(hidden_states)
hidden_states = gate_score * hidden_states
return hidden_states
class CpmAntFeedForward(nn.Module):
def __init__(self, config: CpmAntConfig):
super().__init__()
self.w_in = CpmAntDenseGatedACT(config)
if config.dropout_p is not None:
self.dropout = torch.nn.Dropout(config.dropout_p)
else:
self.dropout = None
self.w_out = nn.Linear(config.dim_ff, config.hidden_size, bias=False)
def forward(self, hidden_states: torch.Tensor):
"""
Args:
hidden_states (`torch.Tensor` of shape `(batch, seq_len, dim_in)`)
"""
hidden_states = self.w_in(hidden_states)
if self.dropout is not None:
hidden_states = self.dropout(hidden_states)
hidden_states = self.w_out(hidden_states)
return hidden_states
class CpmAntFFNBlock(nn.Module):
def __init__(self, config: CpmAntConfig):
super().__init__()
self.layernorm_before_ffn = CpmAntLayerNorm(config)
self.ffn = CpmAntFeedForward(config)
if config.dropout_p:
self.dropout = torch.nn.Dropout(config.dropout_p)
else:
self.dropout = None
def forward(
self,
hidden_states: torch.Tensor,
):
"""
Args:
hidden_states (`torch.Tensor` of shape `(batch, len_seq, dim_model)`):
Hidden states before feed forward layer.
"""
ln_outputs = self.layernorm_before_ffn(hidden_states)
outputs = self.ffn(ln_outputs)
if self.dropout is not None:
outputs = self.dropout(outputs)
hidden_states = hidden_states + outputs
return hidden_states
class CpmAntTransformerBlock(nn.Module):
def __init__(self, config: CpmAntConfig):
super().__init__()
self.self_att = CpmAntSelfAttentionBlock(config)
self.ffn = CpmAntFFNBlock(config)
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: torch.Tensor,
position_bias: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = False,
past_key_values: Optional[Tuple[torch.Tensor, torch.Tensor]] = None,
use_cache: Optional[bool] = None,
):
"""
Args:
hidden_states (`torch.Tensor`):
Input to the layer of shape `(batch, seq_len, dim_model)`
attention_mask (`torch.Tensor`):
Avoid invalid areas to participate in the calculation of shape `(batch, seq_len, seq_len)`
position_bias (`torch.Tensor`):
Provides position information to attention mechanism of shape `(num_heads, seq_len, seq_len)`
output_attentions (`bool`, *optional*):
Whether or not to return the attentions tensors of all attention layers.
past_key_values (`Tuple[torch.Tensor, torch.Tensor])`, *optional*):
Cached past key and value projection states
use_cache (`bool`, *optional*):
If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding
(see `past_key_values`).
"""
hidden_states = self.self_att(
hidden_states,
attention_mask=attention_mask,
position_bias=position_bias,
output_attentions=output_attentions,
past_key_values=past_key_values,
use_cache=use_cache,
)
hidden_states, attn_weights, current_key_value = hidden_states
hidden_states = self.ffn(hidden_states)
return hidden_states, attn_weights, current_key_value
class CpmAntEncoder(nn.Module):
def __init__(self, config: CpmAntConfig):
super().__init__()
self.num_layers = config.num_hidden_layers
self.layers = nn.ModuleList([CpmAntTransformerBlock(config) for ith in range(self.num_layers)])
self.output_layernorm = CpmAntLayerNorm(config)
def forward(
self,
hidden_states: torch.Tensor,
attention_mask: torch.Tensor,
position_bias: torch.Tensor,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
past_key_values: Optional[Tuple[torch.Tensor, torch.Tensor]] = None,
use_cache: Optional[bool] = None,
):
"""
Args:
hidden_states (`torch.Tensor`):
Input to the layer of shape `(batch, seq_len, dim_model)`
attention_mask (`torch.Tensor`):
Avoid invalid areas to participate in the calculation of shape `(batch, seq_len, seq_len)`
position_bias (`torch.Tensor`):
Provides position information to attention mechanism of shape `(num_heads, seq_len, seq_len)`
output_attentions (`bool`, *optional*):
Whether or not to return the attentions tensors of all attention layers.
output_hidden_states (`bool`, *optional*):
Whether or not to return the hidden states of all layers.
past_key_values (`Tuple[torch.Tensor, torch.Tensor])`, *optional*):
Cached past key and value projection states
use_cache (`bool`, *optional*):
If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding
(see `past_key_values`).
"""
all_hidden_states = () if output_hidden_states else None
all_self_attns = () if output_attentions else None
current_key_values = () if use_cache else None
for i, layer in enumerate(self.layers):
if output_hidden_states:
all_hidden_states += (hidden_states,)
layer_outputs = layer(
hidden_states,
attention_mask,
position_bias,
output_attentions=output_attentions,
past_key_values=past_key_values[i] if past_key_values else None,
use_cache=use_cache,
)
hidden_states, attn_weights, current_key_value = layer_outputs
if output_attentions:
all_self_attns += (attn_weights,)
if current_key_value is not None:
current_key_values = current_key_values + (current_key_value,)
hidden_states = self.output_layernorm(hidden_states)
if output_hidden_states:
all_hidden_states += (hidden_states,)
return hidden_states, current_key_values, all_hidden_states, all_self_attns
# Copied from transformers.models.bert.modeling_bert.BertIntermediate with Bert->CPMAnt
class CpmAntIntermediate(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 CpmAntSegmentPositionEmbedding(nn.Module):
def __init__(self, config: CpmAntConfig):
super().__init__()
self.num_heads = config.num_attention_heads
self.num_buckets = config.position_bias_num_buckets
self.max_distance = config.position_bias_max_distance
self.num_segments = config.segment_types
self.relative_attention_bias = nn.Parameter(
torch.empty(
config.segment_types * config.segment_types + config.position_bias_num_buckets,
config.num_attention_heads,
)
)
def forward(
self,
key_pos: torch.Tensor,
query_pos: torch.Tensor,
key_segment: torch.Tensor,
query_segment: torch.Tensor,
):
with torch.no_grad():
batch = key_pos.size(0)
keylen = key_pos.size(1)
querylen = query_pos.size(1)
if key_pos.size(0) != query_pos.size(0):
raise AssertionError(
f"key_pos.size(0) should be equal to query_pos.size(0), but got {key_pos.size(0)} and {query_pos.size(0)}!"
)
if keylen != key_segment.size(1) or querylen != query_segment.size(1):
raise AssertionError(
f"keylen should be equal to key_segment.size(1), but got {keylen} and {key_segment.size(1)}!"
)
if querylen != query_segment.size(1):
raise AssertionError(
f"querylen should be equal to query_segment.size(1), but got {querylen} and {query_segment.szie(1)}!"
)
key_pos = key_pos.view(batch, -1, keylen)
query_pos = query_pos.view(batch, querylen, -1)
key_segment = key_segment.view(batch, -1, keylen)
query_segment = query_segment.view(batch, querylen, -1)
relative_position_bucket = self._segment_relative_position_bucket(query_segment, key_segment)
relative_position_bucket = relative_position_bucket + self.num_buckets
# (batch, len_q, len_k)
absolute_position_bucket = self._position_bucket(
torch.arange(keylen, dtype=torch.int32, device=relative_position_bucket.device)[None, :]
- torch.arange(querylen, dtype=torch.int32, device=relative_position_bucket.device)[:, None],
num_buckets=self.num_buckets,
max_distance=self.max_distance,
)
relative_position_bucket = torch.where(
(key_segment == query_segment),
absolute_position_bucket[None, :, :],
relative_position_bucket,
)
# (batch, len_q, len_k, num_heads)
embeds = F.embedding(relative_position_bucket, self.relative_attention_bias)
# (batch, num_heads, len_q, len_k)
embeds = embeds.permute(0, 3, 1, 2).contiguous()
return embeds
def _segment_relative_position_bucket(self, query_segment, key_segment):
return query_segment * self.num_segments + key_segment
def _position_bucket(self, relative_position, num_buckets=32, max_distance=128):
relative_buckets = 0
# always bidirectional in CPMAnt
num_buckets //= 2
relative_buckets = (relative_position > 0).to(torch.int32) * num_buckets
relative_position = torch.abs(relative_position)
max_exact = num_buckets // 2
is_small = relative_position < max_exact
relative_postion_if_large = max_exact + (
torch.log(relative_position.float() / max_exact)
/ math.log(max_distance / max_exact)
* (num_buckets - max_exact)
).to(torch.int32)
relative_postion_if_large = torch.min(
relative_postion_if_large,
torch.full_like(relative_postion_if_large, num_buckets - 1),
)
relative_buckets += torch.where(is_small, relative_position.to(torch.int32), relative_postion_if_large)
return relative_buckets
# Copied from transformers.models.bert.modeling_bert.BertOutput with Bert->CPMAnt
class CpmAntOutput(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 CpmAntPreTrainedModel(PreTrainedModel):
"""
An abstract class to handle weights initialization and a simple interface for downloading and loading pretrained
models.
"""
config_class = CpmAntConfig
base_model_prefix = "cpmant"
supports_gradient_checkpointing = True
def _init_weights(self, module):
"""Initialize the weights"""
if isinstance(module, nn.Linear):
module.weight.data.normal_(mean=0.0, std=self.config.init_std)
if module.bias is not None:
module.bias.data.zero_()
elif isinstance(module, nn.Embedding):
module.weight.data.normal_(mean=0.0, std=self.config.init_std)
if module.padding_idx is not None:
module.weight.data[module.padding_idx].zero_()
elif isinstance(module, nn.LayerNorm):
module.bias.data.zero_()
module.weight.data.fill_(1.0)
elif isinstance(module, CpmAntLayerNorm):
module.weight.data.fill_(1.0)
elif isinstance(module, CpmAntSegmentPositionEmbedding):
module.relative_attention_bias.data.normal_(mean=0.0, std=self.config.init_std)
def _set_gradient_checkpointing(self, module, value=False):
if isinstance(module, CpmAntEncoder):
module.gradient_checkpointing = value
CPMANT_START_DOCSTRING = r"""
This model is a PyTorch [torch.nn.Module](https://pytorch.org/docs/stable/nn.html#torch.nn.Module) sub-class. Use
it as a regular PyTorch Module and refer to the PyTorch documentation for all matter related to general usage and
behavior.
Parameters
config ([`~CpmAntConfig`]): Model configuration class with all the parameters of the
Initializing with a config file does not load the weights associated with the model, only the
configuration. Check out the [`~PreTrainedModel.from_pretrained`] method to load the model weights.
"""
CPMANT_INPUTS_DOCSTRING = r"""
Args:
input_ids (`torch.Tensor` of shape `(batch_size, seq_len)`):
Indices of input sequence tokens in the vocabulary.
Indices can be obtained using [`CPMAntTokenizer`]. See [`PreTrainedTokenizer.encode`] and
[`PreTrainedTokenizer.__call__`] for details.
[What are input IDs?](../glossary#input-ids)
past_key_values (`tuple(tuple(torch.FloatTensor))`, *optional*, returned when `use_cache=True` is passed or when `config.use_cache=True`):
Contains pre-computed hidden-states (key and values in the self-attention blocks and in the cross-attention
blocks) that can be used (see `past_key_values` input) to speed up sequential decoding.
use_cache (`bool`, *optional*):
If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding (see
`past_key_values`).
output_attentions (`bool`, *optional*):
Whether or not to return the attentions tensors of all attention layers.
output_hidden_states (`bool`, *optional*):
Whether or not to return the hidden states of all layers.
return_dict (`bool`, *optional*):
Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple.
"""
@add_start_docstrings(
"The bare CPMAnt Model outputting raw hidden-states without any specific head on top.",
CPMANT_START_DOCSTRING,
)
class CpmAntModel(CpmAntPreTrainedModel):
def __init__(self, config: CpmAntConfig):
super().__init__(config)
self.encoder = CpmAntEncoder(config)
self.segment_embedding = nn.Embedding(config.segment_types, config.hidden_size)
self.input_embedding = nn.Embedding(
config.vocab_size + config.prompt_types * config.prompt_length, config.hidden_size
)
self.position_bias = CpmAntSegmentPositionEmbedding(config)
self.prompt_length = config.prompt_length
self.vocab_size = config.vocab_size
self.post_init()
def get_input_embeddings(self):
return self.input_embedding
def set_input_embeddings(self, embeddings, **kwargs):
self.input_embedding = embeddings
def _prepare_attention_mask(self, input_ids, span, context, length):
batch = input_ids.size(0)
seqlen = input_ids.size(1)
device = input_ids.device
directional_mask_2d = torch.arange(seqlen, device=device) <= torch.arange(seqlen, device=device).view(-1, 1)
attention_mask = context[:, None, :] | (
context[:, :, None].logical_not() & directional_mask_2d.view(1, seqlen, seqlen)
)
attention_mask = attention_mask & (span[:, None, :] == span[:, :, None])
# mask for left padding
mask_1d = (
torch.tensor(list(range(seqlen - self.prompt_length))[::-1], device=device)[None, :].repeat(batch, 1)
< length[:, None]
)
mask_1d = torch.cat((torch.ones(batch, self.prompt_length, device=device).bool(), mask_1d), dim=1)
attention_mask = mask_1d.view(batch, seqlen, 1) & mask_1d.view(batch, 1, seqlen) & attention_mask
return attention_mask
@add_start_docstrings_to_model_forward(CPMANT_INPUTS_DOCSTRING)
@add_code_sample_docstrings(
checkpoint=_CHECKPOINT_FOR_DOC,
output_type=BaseModelOutputWithPast,
config_class=_CONFIG_FOR_DOC,
)
def forward(
self,
input_ids: Optional[torch.Tensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
past_key_values: Optional[Tuple[Tuple[torch.Tensor]]] = None,
use_cache: Optional[bool] = None,
return_dict: Optional[bool] = None,
**kwargs,
) -> Union[Tuple[torch.Tensor], BaseModelOutputWithPast]:
output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
output_hidden_states = (
output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
)
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
use_cache = use_cache if use_cache is not None else self.config.use_cache
# add prompts ahead
if input_ids.dtype != torch.int32:
input_ids = input_ids.to(torch.int32)
dtype, device = input_ids.dtype, input_ids.device
segment = torch.where(input_ids != 0, 2, 0).to(dtype=dtype, device=device)
length = (segment != 0).sum(-1).to(dtype=dtype, device=device)
input_ids = torch.cat(
(
torch.arange(
self.prompt_length * 2 + self.vocab_size,
self.prompt_length * 3 + self.vocab_size,
dtype=dtype,
device=device,
).repeat(input_ids.size(0), 1),
input_ids,
),
dim=1,
)
batch, seq_length = input_ids.size()
segment = torch.cat((torch.zeros(batch, self.prompt_length, dtype=dtype, device=device), segment), dim=1)
context = torch.full((batch, seq_length), 1, dtype=dtype, device=device)
position = torch.arange(seq_length, dtype=dtype, device=device).repeat(batch, 1)
span = torch.full((batch, seq_length), 0, dtype=dtype, device=device)
if past_key_values is None:
past_length = 0
past_key_values = tuple([None] * self.encoder.num_layers)
input_ids = input_ids.contiguous()
hidden_states = self.input_embedding(input_ids)
segment_states = self.segment_embedding(segment)
hidden_states = hidden_states + segment_states
else:
past_length = past_key_values[0][0].size(-2)
segment_states = self.segment_embedding(segment)
hidden_states = self.input_embedding(input_ids) + segment_states[:, -1:, :]
attention_mask = self._prepare_attention_mask(input_ids, span, context, length)
position_bias = self.position_bias(position, position, segment, segment)
attention_mask = attention_mask[:, past_length:, :]
position_bias = position_bias[:, :, past_length:, :]
hidden_states = hidden_states[:, past_length:, :]
hidden_states, present_key_values, all_hidden_states, all_attentions = self.encoder(
hidden_states,
attention_mask,
position_bias,
output_attentions,
output_hidden_states,
past_key_values,
use_cache,
)
if past_length == 0:
hidden_states = hidden_states[:, self.prompt_length :, :]
# drop the prompt
if all_attentions is not None:
new_attentions = ()
for attention in all_attentions:
new_attentions += (attention[:, :, self.prompt_length :, self.prompt_length :],)
all_attentions = new_attentions
if all_hidden_states is not None:
new_hidden_states = ()
for hidden_state in all_hidden_states:
new_hidden_states += (hidden_state[:, self.prompt_length :, :],)
all_hidden_states = new_hidden_states
if not return_dict:
return tuple(
v for v in [hidden_states, present_key_values, all_hidden_states, all_attentions] if v is not None
)
return BaseModelOutputWithPast(
last_hidden_state=hidden_states,
past_key_values=present_key_values,
hidden_states=all_hidden_states,
attentions=all_attentions,
)
@add_start_docstrings(
"""
The CPMAnt Model with a language modeling head on top (linear layer with weights tied to the input embeddings).
""",
CPMANT_START_DOCSTRING,
)
class CpmAntForCausalLM(CpmAntPreTrainedModel):
_tied_weights_keys = ["lm_head.weight"]
def __init__(self, config: CpmAntConfig):
super().__init__(config)
self.cpmant = CpmAntModel(config)
# lm_head.weight is tied to cpmant.input_embedding.weight
self.lm_head = nn.Linear(
config.hidden_size, config.vocab_size + config.prompt_types * config.prompt_length, bias=False
)
self.post_init()
@add_start_docstrings_to_model_forward(CPMANT_INPUTS_DOCSTRING)
@add_code_sample_docstrings(
checkpoint=_CHECKPOINT_FOR_DOC,
output_type=CausalLMOutputWithPast,
config_class=_CONFIG_FOR_DOC,
)
def forward(
self,
input_ids: Optional[torch.Tensor] = None,
past_key_values: Optional[List[Tuple[torch.Tensor, torch.Tensor]]] = None,
use_cache: Optional[bool] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
labels: Optional[torch.Tensor] = None,
return_dict: Optional[bool] = None,
attention_mask: Optional[torch.Tensor] = None, # dummy parameter for text-generation pipeline
**kwargs,
) -> Union[Tuple, CausalLMOutputWithPast]:
r"""
Args:
input_ids (`torch.Tensor` of shape `(batch_size, seq_len)`):
Indices of input sequence tokens in the vocabulary.
Indices can be obtained using [`CPMAntTokenizer`]. See [`PreTrainedTokenizer.encode`] and
[`PreTrainedTokenizer.__call__`] for details.
[What are input IDs?](../glossary#input-ids)
past_key_values (`tuple(tuple(torch.FloatTensor))`, *optional*, returned when `use_cache=True` is passed or when `config.use_cache=True`):
Contains pre-computed hidden-states (key and values in the self-attention blocks and in the
cross-attention blocks) that can be used (see `past_key_values` input) to speed up sequential decoding.
use_cache (`bool`, *optional*):
If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding
(see `past_key_values`).
output_attentions (`bool`, *optional*):
Whether or not to return the attentions tensors of all attention layers.
output_hidden_states (`bool`, *optional*):
Whether or not to return the hidden states of all layers.
labels (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
Labels for computing the masked language modeling loss.
return_dict (`bool`, *optional*):
Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple.
attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
CPMAnt will process attention mask automatically, this parameter is a dummy parameter for
text-generation pipeline.
Example:
Text Generation with CpmAntForCausalLM.
```python
>>> from transformers import CPMAntTokenizer, CpmAntForCausalLM
>>> texts = "今天天气不错,"
>>> model = CpmAntForCausalLM.from_pretrained("openbmb/cpm-ant-10b")
>>> tokenizer = CPMAntTokenizer.from_pretrained("openbmb/cpm-ant-10b")
>>> input_ids = tokenizer(texts, return_tensors="pt")
>>> outputs = model.generate(**input_ids)
>>> output_texts = tokenizer.batch_decode(outputs)
>>> print(output_texts)
['今天天气不错,阳光明媚,我和妈妈一起去超市买东西。\n在超市里,我看到了一个很好玩的玩具,它的名字叫“机器人”。它有一个圆圆的脑袋,两只圆圆的眼睛,还有一个圆圆的']
```
"""
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
model_output = self.cpmant(
input_ids, output_attentions, output_hidden_states, past_key_values, use_cache, return_dict
)
hidden_states = model_output.last_hidden_state if return_dict else model_output[0]
logits = self.lm_head(hidden_states)
loss = None
if labels is not None:
loss_func = CrossEntropyLoss()
loss = loss_func(logits.view(-1, logits.size(-1)), labels.view(-1))
if not return_dict:
output = (logits,) + model_output[1:]
return ((loss,) + output) if loss is not None else output
return CausalLMOutputWithPast(
loss=loss,
logits=logits,
past_key_values=model_output.past_key_values,
hidden_states=model_output.hidden_states,
attentions=model_output.attentions,
)
def get_input_embeddings(self):
return self.cpmant.input_embedding
def set_input_embeddings(self, embeddings):
self.cpmant.input_embedding = embeddings
def get_output_embeddings(self):
return self.lm_head
def set_output_embeddings(self, new_embeddings):
self.lm_head = new_embeddings
def prepare_inputs_for_generation(self, input_ids, **kwargs):
input_ids = input_ids.int()
# save the memory usage of dummy attention mask
if "attention_mask" in kwargs:
kwargs["attention_mask"] = torch.zeros(1, 1)
return {
"input_ids": input_ids,
"use_cache": kwargs["use_cache"],
"past_key_values": kwargs.get("past_key_values", None),
}
def _reorder_cache(self, past_key_values, beam_idx):
past_key_values = [list(each) if each is not None else each for each in past_key_values]
for key_value_layer in past_key_values:
key_value_layer[0] = key_value_layer[0][beam_idx]
key_value_layer[1] = key_value_layer[1][beam_idx]
return past_key_values