chore: import upstream snapshot with attribution

This commit is contained in:
wehub-resource-sync
2026-07-13 13:24:13 +08:00
commit 1037506f2e
6050 changed files with 1731598 additions and 0 deletions
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# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.
from .models import linformer_roberta # noqa
@@ -0,0 +1,134 @@
# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.
"""
Linformer: Self-Attention with Linear Complexity
"""
import logging
from fairseq.models import register_model, register_model_architecture
from fairseq.models.roberta import RobertaEncoder, RobertaModel
from ..modules.linformer_sentence_encoder import LinformerSentenceEncoder
logger = logging.getLogger(__name__)
@register_model("linformer_roberta")
class LinformerModel(RobertaModel):
@staticmethod
def add_args(parser):
RobertaModel.add_args(parser)
# add args for Linformer
parser.add_argument(
"--compressed", type=int, help="compressed ratio of sequence length"
)
parser.add_argument(
"--shared-kv-compressed",
type=int,
help="share compressed matrix between k and v, in each layer",
)
parser.add_argument(
"--shared-layer-kv-compressed",
type=int,
help="share compressed matrix between k and v and across all layers",
)
parser.add_argument(
"--freeze-compress",
type=int,
help="freeze the parameters in compressed layer",
)
@classmethod
def build_model(cls, args, task):
"""Build a new model instance."""
# make sure all arguments are present
base_architecture(args)
if not hasattr(args, "max_positions"):
args.max_positions = args.tokens_per_sample
encoder = LinformerEncoder(args, task.source_dictionary)
return cls(args, encoder)
class LinformerEncoder(RobertaEncoder):
"""Linformer encoder."""
def __init__(self, args, dictionary):
super().__init__(args, dictionary)
self.sentence_encoder = LinformerSentenceEncoder(
padding_idx=dictionary.pad(),
vocab_size=len(dictionary),
num_encoder_layers=args.encoder_layers,
embedding_dim=args.encoder_embed_dim,
ffn_embedding_dim=args.encoder_ffn_embed_dim,
num_attention_heads=args.encoder_attention_heads,
dropout=args.dropout,
attention_dropout=args.attention_dropout,
activation_dropout=args.activation_dropout,
layerdrop=args.encoder_layerdrop,
max_seq_len=args.max_positions,
num_segments=0,
encoder_normalize_before=True,
apply_bert_init=True,
activation_fn=args.activation_fn,
q_noise=args.quant_noise_pq,
qn_block_size=args.quant_noise_pq_block_size,
compressed=args.compressed,
shared_kv_compressed=args.shared_kv_compressed,
shared_layer_kv_compressed=args.shared_layer_kv_compressed,
freeze_compress=args.freeze_compress,
)
@register_model_architecture("linformer_roberta", "linformer_roberta")
def base_architecture(args):
args.encoder_layers = getattr(args, "encoder_layers", 12)
args.encoder_embed_dim = getattr(args, "encoder_embed_dim", 768)
args.encoder_ffn_embed_dim = getattr(args, "encoder_ffn_embed_dim", 3072)
args.encoder_attention_heads = getattr(args, "encoder_attention_heads", 12)
args.activation_fn = getattr(args, "activation_fn", "gelu")
args.pooler_activation_fn = getattr(args, "pooler_activation_fn", "tanh")
args.dropout = getattr(args, "dropout", 0.1)
args.attention_dropout = getattr(args, "attention_dropout", 0.1)
args.activation_dropout = getattr(args, "activation_dropout", 0.0)
args.pooler_dropout = getattr(args, "pooler_dropout", 0.0)
args.encoder_layers_to_keep = getattr(args, "encoder_layers_to_keep", None)
args.encoder_layerdrop = getattr(args, "encoder_layerdrop", 0.0)
args.compressed = getattr(args, "compressed", 4)
args.shared_kv_compressed = getattr(args, "shared_kv_compressed", 0)
args.shared_layer_kv_compressed = getattr(args, "shared_layer_kv_compressed", 0)
args.freeze_compress = getattr(args, "freeze_compress", 0)
@register_model_architecture("linformer_roberta", "linformer_roberta_base")
def linformer_roberta_base_architecture(args):
base_architecture(args)
@register_model_architecture("linformer_roberta", "linformer_roberta_large")
def linformer_roberta_large_architecture(args):
args.encoder_layers = getattr(args, "encoder_layers", 24)
args.encoder_embed_dim = getattr(args, "encoder_embed_dim", 1024)
args.encoder_ffn_embed_dim = getattr(args, "encoder_ffn_embed_dim", 4096)
args.encoder_attention_heads = getattr(args, "encoder_attention_heads", 16)
args.activation_fn = getattr(args, "activation_fn", "gelu")
args.pooler_activation_fn = getattr(args, "pooler_activation_fn", "tanh")
args.dropout = getattr(args, "dropout", 0.1)
args.attention_dropout = getattr(args, "attention_dropout", 0.1)
args.activation_dropout = getattr(args, "activation_dropout", 0.0)
args.pooler_dropout = getattr(args, "pooler_dropout", 0.0)
args.compressed = getattr(args, "compressed", 4)
args.shared_kv_compressed = getattr(args, "shared_kv_compressed", 0)
args.shared_layer_kv_compressed = getattr(args, "shared_layer_kv_compressed", 0)
@@ -0,0 +1,169 @@
# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.
import math
import torch.nn as nn
from fairseq.modules import TransformerSentenceEncoder
from .linformer_sentence_encoder_layer import LinformerSentenceEncoderLayer
class LinformerSentenceEncoder(TransformerSentenceEncoder):
"""
Implementation for a Bi-directional Linformer based Sentence Encoder used
in BERT/XLM style pre-trained models.
This first computes the token embedding using the token embedding matrix,
position embeddings (if specified) and segment embeddings
(if specified). After applying the specified number of
LinformerEncoderLayers, it outputs all the internal states of the
encoder as well as the final representation associated with the first
token (usually CLS token).
Input:
- tokens: B x T matrix representing sentences
- segment_labels: B x T matrix representing segment label for tokens
Output:
- a tuple of the following:
- a list of internal model states used to compute the
predictions where each tensor has shape T x B x C
- sentence representation associated with first input token
in format B x C.
"""
def __init__(
self,
padding_idx: int,
vocab_size: int,
num_encoder_layers: int = 6,
embedding_dim: int = 768,
ffn_embedding_dim: int = 3072,
num_attention_heads: int = 8,
dropout: float = 0.1,
attention_dropout: float = 0.1,
activation_dropout: float = 0.1,
layerdrop: float = 0.0,
max_seq_len: int = 256,
num_segments: int = 2,
use_position_embeddings: bool = True,
offset_positions_by_padding: bool = True,
encoder_normalize_before: bool = False,
apply_bert_init: bool = False,
activation_fn: str = "relu",
learned_pos_embedding: bool = True,
embed_scale: float = None,
freeze_embeddings: bool = False,
n_trans_layers_to_freeze: int = 0,
export: bool = False,
traceable: bool = False,
q_noise: float = 0.0,
qn_block_size: int = 8,
compressed: int = 4,
shared_kv_compressed: int = 0,
shared_layer_kv_compressed: int = 0,
freeze_compress: int = 0,
) -> None:
# Initialize linformer parameters
self.compressed = compressed
self.shared_kv_compressed = shared_kv_compressed
self.shared_layer_kv_compressed = shared_layer_kv_compressed
self.compress_layer = None
self.freeze_compress = freeze_compress
super().__init__(
padding_idx=padding_idx,
vocab_size=vocab_size,
num_encoder_layers=num_encoder_layers,
embedding_dim=embedding_dim,
ffn_embedding_dim=ffn_embedding_dim,
num_attention_heads=num_attention_heads,
dropout=dropout,
attention_dropout=attention_dropout,
activation_dropout=activation_dropout,
layerdrop=layerdrop,
max_seq_len=max_seq_len,
num_segments=num_segments,
use_position_embeddings=use_position_embeddings,
offset_positions_by_padding=offset_positions_by_padding,
encoder_normalize_before=encoder_normalize_before,
apply_bert_init=apply_bert_init,
activation_fn=activation_fn,
learned_pos_embedding=learned_pos_embedding,
embed_scale=embed_scale,
freeze_embeddings=freeze_embeddings,
n_trans_layers_to_freeze=n_trans_layers_to_freeze,
export=export,
traceable=traceable,
q_noise=q_noise,
qn_block_size=qn_block_size,
)
def build_transformer_sentence_encoder_layer(
self,
embedding_dim,
ffn_embedding_dim,
num_attention_heads,
dropout,
attention_dropout,
activation_dropout,
activation_fn,
export,
q_noise,
qn_block_size,
):
if self.shared_layer_kv_compressed == 1:
compress_layer = nn.Linear(
self.max_seq_len, self.max_seq_len // self.compressed
)
# intialize parameters for compressed layer
nn.init.xavier_uniform_(compress_layer.weight, gain=1 / math.sqrt(2))
if self.freeze_compress == 1:
compress_layer.weight.requires_grad = False
self.compress_layer = compress_layer
return LinformerSentenceEncoderLayer(
embedding_dim=embedding_dim,
ffn_embedding_dim=ffn_embedding_dim,
num_attention_heads=num_attention_heads,
dropout=dropout,
attention_dropout=attention_dropout,
activation_dropout=activation_dropout,
activation_fn=activation_fn,
export=export,
q_noise=q_noise,
qn_block_size=qn_block_size,
compressed=self.compressed,
max_seq_len=self.max_seq_len,
shared_kv_compressed=self.shared_kv_compressed,
shared_compress_layer=(
None if self.shared_layer_kv_compressed == 0 else self.compress_layer
),
freeze_compress=self.freeze_compress,
)
def upgrade_state_dict_named(self, state_dict, name):
prefix = name + "." if name != "" else ""
items_to_add = {}
keys_to_remove = []
# update key name for shared layer in new version of code
for k in state_dict.keys():
if k.startswith(prefix + "compress_layer"):
if self.shared_layer_kv_compressed:
for layer_idx in range(len(self.layers)):
new_k = prefix + "layers.{0}.shared_compress_layer.{1}".format(
layer_idx,
k[len(prefix + "compress_layer.") :],
)
items_to_add[new_k] = state_dict[k]
for k in keys_to_remove:
del state_dict[k]
for key, value in items_to_add.items():
state_dict[key] = value
@@ -0,0 +1,84 @@
# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.
from typing import Callable
from fairseq.modules import TransformerSentenceEncoderLayer
from .multihead_linear_attention import MultiheadLinearAttention
class LinformerSentenceEncoderLayer(TransformerSentenceEncoderLayer):
"""
Implements a Linformer Encoder Layer used in BERT/XLM style pre-trained
models.
"""
def __init__(
self,
embedding_dim: int = 768,
ffn_embedding_dim: int = 3072,
num_attention_heads: int = 8,
dropout: float = 0.1,
attention_dropout: float = 0.1,
activation_dropout: float = 0.1,
activation_fn: str = "relu",
export: bool = False,
q_noise: float = 0.0,
qn_block_size: int = 8,
init_fn: Callable = None,
compressed: int = 1,
max_seq_len: int = 256,
shared_kv_compressed: int = 0,
shared_compress_layer: any = None,
freeze_compress: int = 0,
) -> None:
# Initialize linformer parameters
self.compressed = compressed
self.max_seq_len = max_seq_len
self.shared_kv_compressed = shared_kv_compressed
self.freeze_compress = freeze_compress
def init_fn():
# This needs to be set after nn.Module.__init__ is called
self.shared_compress_layer = shared_compress_layer
super().__init__(
embedding_dim=embedding_dim,
ffn_embedding_dim=ffn_embedding_dim,
num_attention_heads=num_attention_heads,
dropout=dropout,
attention_dropout=attention_dropout,
activation_dropout=activation_dropout,
activation_fn=activation_fn,
export=export,
q_noise=q_noise,
qn_block_size=qn_block_size,
init_fn=init_fn,
)
def build_self_attention(
self,
embed_dim,
num_attention_heads,
dropout,
self_attention,
q_noise,
qn_block_size,
):
return MultiheadLinearAttention(
embed_dim,
num_attention_heads,
dropout=dropout,
self_attention=True,
q_noise=q_noise,
qn_block_size=qn_block_size,
compressed=self.compressed,
max_seq_len=self.max_seq_len,
shared_kv_compressed=self.shared_kv_compressed,
shared_compress_layer=self.shared_compress_layer,
freeze_compress=self.freeze_compress,
)
@@ -0,0 +1,481 @@
# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.
import math
from typing import Dict, Optional, Tuple
import torch
import torch.nn.functional as F
from fairseq import utils
from fairseq.incremental_decoding_utils import with_incremental_state
from fairseq.modules.quant_noise import quant_noise
from torch import Tensor, nn
from torch.nn import Parameter
@with_incremental_state
class MultiheadLinearAttention(nn.Module):
"""Multi-headed linformer attention.
Projects the key and values down to the compressed dimension, before computing self-attention.
See "Linformer: Self-Attention with Linear Complexity" for more details.
"""
def __init__(
self,
embed_dim,
num_heads,
kdim=None,
vdim=None,
dropout=0.0,
bias=True,
add_bias_kv=False,
add_zero_attn=False,
self_attention=False,
encoder_decoder_attention=False,
q_noise=0.0,
qn_block_size=8,
compressed=1,
max_seq_len=256,
shared_kv_compressed=0,
shared_compress_layer=None,
freeze_compress=0,
):
super().__init__()
self.embed_dim = embed_dim
self.kdim = kdim if kdim is not None else embed_dim
self.vdim = vdim if vdim is not None else embed_dim
self.qkv_same_dim = self.kdim == embed_dim and self.vdim == embed_dim
self.num_heads = num_heads
self.dropout = dropout
self.head_dim = embed_dim // num_heads
assert (
self.head_dim * num_heads == self.embed_dim
), "embed_dim must be divisible by num_heads"
self.scaling = self.head_dim ** -0.5
self.self_attention = self_attention
self.encoder_decoder_attention = encoder_decoder_attention
assert not self.self_attention or self.qkv_same_dim, (
"Self-attention requires query, key and " "value to be of the same size"
)
self.k_proj = quant_noise(
nn.Linear(self.kdim, embed_dim, bias=bias), q_noise, qn_block_size
)
self.v_proj = quant_noise(
nn.Linear(self.vdim, embed_dim, bias=bias), q_noise, qn_block_size
)
self.q_proj = quant_noise(
nn.Linear(embed_dim, embed_dim, bias=bias), q_noise, qn_block_size
)
# used for compress sequence to subsequence
if shared_compress_layer is None:
self.compress_seq_len = max_seq_len // compressed
self.compress_k = nn.Linear(max_seq_len, self.compress_seq_len, bias=False)
if shared_kv_compressed == 0:
self.compress_v = nn.Linear(
max_seq_len, self.compress_seq_len, bias=False
)
self.layerwise_sharing = False
else:
self.compress_k = shared_compress_layer
if shared_kv_compressed == 0:
self.compress_v = shared_compress_layer
self.layerwise_sharing = True
self.shared_kv_compressed = shared_kv_compressed
self.out_proj = quant_noise(
nn.Linear(embed_dim, embed_dim, bias=bias), q_noise, qn_block_size
)
if add_bias_kv:
self.bias_k = Parameter(torch.Tensor(1, 1, embed_dim))
self.bias_v = Parameter(torch.Tensor(1, 1, embed_dim))
else:
self.bias_k = self.bias_v = None
self.add_zero_attn = add_zero_attn
self.reset_parameters()
if freeze_compress == 1:
self.compress_k.weight.requires_grad = False
if shared_kv_compressed == 0:
self.compress_v.weight.requires_grad = False
self.onnx_trace = False
def prepare_for_onnx_export_(self):
self.onnx_trace = True
def reset_parameters(self):
if self.qkv_same_dim:
# Empirically observed the convergence to be much better with
# the scaled initialization
nn.init.xavier_uniform_(self.k_proj.weight, gain=1 / math.sqrt(2))
nn.init.xavier_uniform_(self.v_proj.weight, gain=1 / math.sqrt(2))
nn.init.xavier_uniform_(self.q_proj.weight, gain=1 / math.sqrt(2))
if (
not self.layerwise_sharing
): # otherwise, we already initialize the parameters
nn.init.xavier_uniform_(self.compress_k.weight, gain=1 / math.sqrt(2))
if self.shared_kv_compressed == 0:
nn.init.xavier_uniform_(
self.compress_v.weight, gain=1 / math.sqrt(2)
)
else:
nn.init.xavier_uniform_(self.k_proj.weight)
nn.init.xavier_uniform_(self.v_proj.weight)
nn.init.xavier_uniform_(self.q_proj.weight)
if (
not self.layerwise_sharing
): # otherwise, we already initialize the parameters
nn.init.xavier_uniform_(self.compress_k.weight)
if self.shared_kv_compressed == 0:
nn.init.xavier_uniform_(self.compress_v.weight)
nn.init.xavier_uniform_(self.out_proj.weight)
if self.out_proj.bias is not None:
nn.init.constant_(self.out_proj.bias, 0.0)
if self.bias_k is not None:
nn.init.xavier_normal_(self.bias_k)
if self.bias_v is not None:
nn.init.xavier_normal_(self.bias_v)
def forward(
self,
query,
key: Optional[Tensor],
value: Optional[Tensor],
key_padding_mask: Optional[Tensor] = None,
incremental_state: Optional[Dict[str, Dict[str, Optional[Tensor]]]] = None,
need_weights: bool = True,
static_kv: bool = False,
attn_mask: Optional[Tensor] = None,
before_softmax: bool = False,
need_head_weights: bool = False,
) -> Tuple[Tensor, Optional[Tensor]]:
"""Input shape: Time x Batch x Channel
Args:
key_padding_mask (ByteTensor, optional): mask to exclude
keys that are pads, of shape `(batch, src_len)`, where
padding elements are indicated by 1s.
need_weights (bool, optional): return the attention weights,
averaged over heads (default: False).
attn_mask (ByteTensor, optional): typically used to
implement causal attention, where the mask prevents the
attention from looking forward in time (default: None).
before_softmax (bool, optional): return the raw attention
weights and values before the attention softmax.
need_head_weights (bool, optional): return the attention
weights for each head. Implies *need_weights*. Default:
return the average attention weights over all heads.
"""
if need_head_weights:
need_weights = True
tgt_len, bsz, embed_dim = query.size()
assert embed_dim == self.embed_dim
assert list(query.size()) == [tgt_len, bsz, embed_dim]
if incremental_state is not None:
saved_state = self._get_input_buffer(incremental_state)
if saved_state is not None and "prev_key" in saved_state:
# previous time steps are cached - no need to recompute
# key and value if they are static
if static_kv:
assert self.encoder_decoder_attention and not self.self_attention
key = value = None
else:
saved_state = None
if self.self_attention:
q = self.q_proj(query)
k_input = query.permute(1, 2, 0).contiguous() # B * C * T
k_input = (
F.linear(k_input, self.compress_k.weight[:, 0:tgt_len])
.permute(2, 0, 1)
.contiguous()
)
k = self.k_proj(k_input)
v_input = query.permute(1, 2, 0).contiguous() # B * C * T
if self.shared_kv_compressed == 0:
v_input = (
F.linear(v_input, self.compress_v.weight[:, 0:tgt_len])
.permute(2, 0, 1)
.contiguous()
)
if self.shared_kv_compressed == 1: # use shared kv compressed linear layer
v_input = (
F.linear(v_input, self.compress_k.weight[:, 0:tgt_len])
.permute(2, 0, 1)
.contiguous()
)
v = self.v_proj(v_input)
elif self.encoder_decoder_attention:
# encoder-decoder attention
q = self.q_proj(query)
if key is None:
assert value is None
k = v = None
else:
k = self.k_proj(key)
v = self.v_proj(key)
else:
assert key is not None and value is not None
q = self.q_proj(query)
k = self.k_proj(key)
v = self.v_proj(value)
q *= self.scaling
if self.bias_k is not None:
assert self.bias_v is not None
k = torch.cat([k, self.bias_k.repeat(1, bsz, 1)])
v = torch.cat([v, self.bias_v.repeat(1, bsz, 1)])
if attn_mask is not None:
attn_mask = torch.cat(
[attn_mask, attn_mask.new_zeros(attn_mask.size(0), 1)], dim=1
)
if key_padding_mask is not None:
key_padding_mask = torch.cat(
[
key_padding_mask,
key_padding_mask.new_zeros(key_padding_mask.size(0), 1),
],
dim=1,
)
q = (
q.contiguous()
.view(tgt_len, bsz * self.num_heads, self.head_dim)
.transpose(0, 1)
)
if k is not None:
k = (
k.contiguous()
.view(-1, bsz * self.num_heads, self.head_dim)
.transpose(0, 1)
)
if v is not None:
v = (
v.contiguous()
.view(-1, bsz * self.num_heads, self.head_dim)
.transpose(0, 1)
)
if saved_state is not None:
# saved states are stored with shape (bsz, num_heads, seq_len, head_dim)
if "prev_key" in saved_state:
_prev_key = saved_state["prev_key"]
assert _prev_key is not None
prev_key = _prev_key.view(bsz * self.num_heads, -1, self.head_dim)
if static_kv:
k = prev_key
else:
assert k is not None
k = torch.cat([prev_key, k], dim=1)
if "prev_value" in saved_state:
_prev_value = saved_state["prev_value"]
assert _prev_value is not None
prev_value = _prev_value.view(bsz * self.num_heads, -1, self.head_dim)
if static_kv:
v = prev_value
else:
assert v is not None
v = torch.cat([prev_value, v], dim=1)
prev_key_padding_mask: Optional[Tensor] = None
if "prev_key_padding_mask" in saved_state:
prev_key_padding_mask = saved_state["prev_key_padding_mask"]
assert k is not None and v is not None
key_padding_mask = MultiheadLinearAttention._append_prev_key_padding_mask(
key_padding_mask=key_padding_mask,
prev_key_padding_mask=prev_key_padding_mask,
batch_size=bsz,
src_len=k.size(1),
static_kv=static_kv,
)
saved_state["prev_key"] = k.view(bsz, self.num_heads, -1, self.head_dim)
saved_state["prev_value"] = v.view(bsz, self.num_heads, -1, self.head_dim)
saved_state["prev_key_padding_mask"] = key_padding_mask
# In this branch incremental_state is never None
assert incremental_state is not None
incremental_state = self._set_input_buffer(incremental_state, saved_state)
assert k is not None
src_len = k.size(1)
if self.add_zero_attn:
assert v is not None
src_len += 1
k = torch.cat([k, k.new_zeros((k.size(0), 1) + k.size()[2:])], dim=1)
v = torch.cat([v, v.new_zeros((v.size(0), 1) + v.size()[2:])], dim=1)
if attn_mask is not None:
attn_mask = torch.cat(
[attn_mask, attn_mask.new_zeros(attn_mask.size(0), 1)], dim=1
)
attn_weights = torch.bmm(q, k.transpose(1, 2))
attn_weights = MultiheadLinearAttention.apply_sparse_mask(
attn_weights, tgt_len, src_len, bsz
)
assert list(attn_weights.size()) == [bsz * self.num_heads, tgt_len, src_len]
if attn_mask is not None:
attn_mask = attn_mask.unsqueeze(0)
if self.onnx_trace:
attn_mask = attn_mask.repeat(attn_weights.size(0), 1, 1)
attn_weights += attn_mask
if before_softmax:
return attn_weights, v
attn_weights_float = utils.softmax(
attn_weights, dim=-1, onnx_trace=self.onnx_trace
)
attn_weights = attn_weights_float.type_as(attn_weights)
attn_probs = F.dropout(
attn_weights,
p=self.dropout,
training=self.training,
)
assert v is not None
attn = torch.bmm(attn_probs, v)
assert list(attn.size()) == [bsz * self.num_heads, tgt_len, self.head_dim]
if self.onnx_trace and attn.size(1) == 1:
# when ONNX tracing a single decoder step (sequence length == 1)
# the transpose is a no-op copy before view, thus unnecessary
attn = attn.contiguous().view(tgt_len, bsz, embed_dim)
else:
attn = attn.transpose(0, 1).contiguous().view(tgt_len, bsz, embed_dim)
attn = self.out_proj(attn)
attn_weights: Optional[Tensor] = None
if need_weights:
attn_weights = attn_weights_float.view(
bsz, self.num_heads, tgt_len, src_len
).transpose(1, 0)
if not need_head_weights:
# average attention weights over heads
attn_weights = attn_weights.mean(dim=0)
return attn, attn_weights
@staticmethod
def _append_prev_key_padding_mask(
key_padding_mask: Optional[Tensor],
prev_key_padding_mask: Optional[Tensor],
batch_size: int,
src_len: int,
static_kv: bool,
) -> Optional[Tensor]:
# saved key padding masks have shape (bsz, seq_len)
if prev_key_padding_mask is not None and static_kv:
new_key_padding_mask = prev_key_padding_mask
elif prev_key_padding_mask is not None and key_padding_mask is not None:
new_key_padding_mask = torch.cat(
[prev_key_padding_mask.float(), key_padding_mask.float()], dim=1
)
# During incremental decoding, as the padding token enters and
# leaves the frame, there will be a time when prev or current
# is None
elif prev_key_padding_mask is not None:
filler = torch.zeros(
(batch_size, src_len - prev_key_padding_mask.size(1)),
device=prev_key_padding_mask.device,
)
new_key_padding_mask = torch.cat(
[prev_key_padding_mask.float(), filler.float()], dim=1
)
elif key_padding_mask is not None:
filler = torch.zeros(
(batch_size, src_len - key_padding_mask.size(1)),
device=key_padding_mask.device,
)
new_key_padding_mask = torch.cat(
[filler.float(), key_padding_mask.float()], dim=1
)
else:
new_key_padding_mask = prev_key_padding_mask
return new_key_padding_mask
@torch.jit.export
def reorder_incremental_state(
self,
incremental_state: Dict[str, Dict[str, Optional[Tensor]]],
new_order: Tensor,
):
"""Reorder buffered internal state (for incremental generation)."""
input_buffer = self._get_input_buffer(incremental_state)
if input_buffer is not None:
for k in input_buffer.keys():
input_buffer_k = input_buffer[k]
if input_buffer_k is not None:
if self.encoder_decoder_attention and input_buffer_k.size(
0
) == new_order.size(0):
break
input_buffer[k] = input_buffer_k.index_select(0, new_order)
incremental_state = self._set_input_buffer(incremental_state, input_buffer)
return incremental_state
def _get_input_buffer(
self, incremental_state: Optional[Dict[str, Dict[str, Optional[Tensor]]]]
) -> Dict[str, Optional[Tensor]]:
result = self.get_incremental_state(incremental_state, "attn_state")
if result is not None:
return result
else:
empty_result: Dict[str, Optional[Tensor]] = {}
return empty_result
def _set_input_buffer(
self,
incremental_state: Dict[str, Dict[str, Optional[Tensor]]],
buffer: Dict[str, Optional[Tensor]],
):
return self.set_incremental_state(incremental_state, "attn_state", buffer)
def apply_sparse_mask(attn_weights, tgt_len: int, src_len: int, bsz: int):
return attn_weights
def upgrade_state_dict_named(self, state_dict, name):
prefix = name + "." if name != "" else ""
items_to_add = {}
keys_to_remove = []
for k in state_dict.keys():
if k.endswith(prefix + "in_proj_weight"):
# in_proj_weight used to be q + k + v with same dimensions
dim = int(state_dict[k].shape[0] / 3)
items_to_add[prefix + "q_proj.weight"] = state_dict[k][:dim]
items_to_add[prefix + "k_proj.weight"] = state_dict[k][dim : 2 * dim]
items_to_add[prefix + "v_proj.weight"] = state_dict[k][2 * dim :]
keys_to_remove.append(k)
k_bias = prefix + "in_proj_bias"
if k_bias in state_dict.keys():
dim = int(state_dict[k].shape[0] / 3)
items_to_add[prefix + "q_proj.bias"] = state_dict[k_bias][:dim]
items_to_add[prefix + "k_proj.bias"] = state_dict[k_bias][
dim : 2 * dim
]
items_to_add[prefix + "v_proj.bias"] = state_dict[k_bias][2 * dim :]
keys_to_remove.append(prefix + "in_proj_bias")
for k in keys_to_remove:
del state_dict[k]
for key, value in items_to_add.items():
state_dict[key] = value