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# --------------------------------------------------------
# WavLM: Large-Scale Self-Supervised Pre-training for Full Stack Speech Processing (https://arxiv.org/abs/2110.13900.pdf)
# Github source: https://github.com/microsoft/unilm/tree/master/wavlm
# Copyright (c) 2021 Microsoft
# Licensed under The MIT License [see LICENSE for details]
# Based on fairseq code bases
# https://github.com/pytorch/fairseq
# --------------------------------------------------------
import math
import warnings
from typing import Dict, Optional, Tuple
import torch
import torch.nn.functional as F
from torch import Tensor, nn
from torch.nn import Parameter
class TransposeLast(nn.Module):
def __init__(self, deconstruct_idx=None):
super().__init__()
self.deconstruct_idx = deconstruct_idx
def forward(self, x):
if self.deconstruct_idx is not None:
x = x[self.deconstruct_idx]
return x.transpose(-2, -1)
class Fp32LayerNorm(nn.LayerNorm):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
def forward(self, input):
output = F.layer_norm(
input.float(),
self.normalized_shape,
self.weight.float() if self.weight is not None else None,
self.bias.float() if self.bias is not None else None,
self.eps,
)
return output.type_as(input)
class Fp32GroupNorm(nn.GroupNorm):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
def forward(self, input):
output = F.group_norm(
input.float(),
self.num_groups,
self.weight.float() if self.weight is not None else None,
self.bias.float() if self.bias is not None else None,
self.eps,
)
return output.type_as(input)
class GradMultiply(torch.autograd.Function):
@staticmethod
def forward(ctx, x, scale):
ctx.scale = scale
res = x.new(x)
return res
@staticmethod
def backward(ctx, grad):
return grad * ctx.scale, None
class SamePad(nn.Module):
def __init__(self, kernel_size, causal=False):
super().__init__()
if causal:
self.remove = kernel_size - 1
else:
self.remove = 1 if kernel_size % 2 == 0 else 0
def forward(self, x):
if self.remove > 0:
x = x[:, :, : -self.remove]
return x
class Swish(nn.Module):
"""Swish function
"""
def __init__(self):
"""Construct an MultiHeadedAttention object."""
super(Swish, self).__init__()
self.act = torch.nn.Sigmoid()
def forward(self, x):
return x * self.act(x)
class GLU_Linear(nn.Module):
def __init__(self, input_dim, output_dim, glu_type="sigmoid", bias_in_glu=True):
super(GLU_Linear, self).__init__()
self.glu_type = glu_type
self.output_dim = output_dim
if glu_type == "sigmoid":
self.glu_act = torch.nn.Sigmoid()
elif glu_type == "swish":
self.glu_act = Swish()
elif glu_type == "relu":
self.glu_act = torch.nn.ReLU()
elif glu_type == "gelu":
self.glu_act = torch.nn.GELU()
if bias_in_glu:
self.linear = nn.Linear(input_dim, output_dim * 2, True)
else:
self.linear = nn.Linear(input_dim, output_dim * 2, False)
def forward(self, x):
# to be consistent with GLU_Linear, we assume the input always has the #channel (#dim) in the last dimension of the tensor, so need to switch the dimension first for 1D-Conv case
x = self.linear(x)
if self.glu_type == "bilinear":
x = (x[:, :, 0:self.output_dim] * x[:, :, self.output_dim:self.output_dim * 2])
else:
x = (x[:, :, 0:self.output_dim] * self.glu_act(x[:, :, self.output_dim:self.output_dim * 2]))
return x
def gelu_accurate(x):
if not hasattr(gelu_accurate, "_a"):
gelu_accurate._a = math.sqrt(2 / math.pi)
return (
0.5 * x * (1 + torch.tanh(gelu_accurate._a * (x + 0.044715 * torch.pow(x, 3))))
)
def gelu(x: torch.Tensor) -> torch.Tensor:
return torch.nn.functional.gelu(x.float()).type_as(x)
def get_activation_fn(activation: str):
"""Returns the activation function corresponding to `activation`"""
if activation == "relu":
return F.relu
elif activation == "gelu":
return gelu
elif activation == "gelu_fast":
warnings.warn(
"--activation-fn=gelu_fast has been renamed to gelu_accurate"
)
return gelu_accurate
elif activation == "gelu_accurate":
return gelu_accurate
elif activation == "tanh":
return torch.tanh
elif activation == "linear":
return lambda x: x
elif activation == "glu":
return lambda x: x
else:
raise RuntimeError("--activation-fn {} not supported".format(activation))
def init_bert_params(module):
"""
Initialize the weights specific to the BERT Model.
This overrides the default initializations depending on the specified arguments.
1. If normal_init_linear_weights is set then weights of linear
layer will be initialized using the normal distribution and
bais will be set to the specified value.
2. If normal_init_embed_weights is set then weights of embedding
layer will be initialized using the normal distribution.
3. If normal_init_proj_weights is set then weights of
in_project_weight for MultiHeadAttention initialized using
the normal distribution (to be validated).
"""
def normal_(data):
# with FSDP, module params will be on CUDA, so we cast them back to CPU
# so that the RNG is consistent with and without FSDP
data.copy_(
data.cpu().normal_(mean=0.0, std=0.02).to(data.device)
)
if isinstance(module, nn.Linear):
normal_(module.weight.data)
if module.bias is not None:
module.bias.data.zero_()
if isinstance(module, nn.Embedding):
normal_(module.weight.data)
if module.padding_idx is not None:
module.weight.data[module.padding_idx].zero_()
if isinstance(module, MultiheadAttention):
normal_(module.q_proj.weight.data)
normal_(module.k_proj.weight.data)
normal_(module.v_proj.weight.data)
def quant_noise(module, p, block_size):
"""
Wraps modules and applies quantization noise to the weights for
subsequent quantization with Iterative Product Quantization as
described in "Training with Quantization Noise for Extreme Model Compression"
Args:
- module: nn.Module
- p: amount of Quantization Noise
- block_size: size of the blocks for subsequent quantization with iPQ
Remarks:
- Module weights must have the right sizes wrt the block size
- Only Linear, Embedding and Conv2d modules are supported for the moment
- For more detail on how to quantize by blocks with convolutional weights,
see "And the Bit Goes Down: Revisiting the Quantization of Neural Networks"
- We implement the simplest form of noise here as stated in the paper
which consists in randomly dropping blocks
"""
# if no quantization noise, don't register hook
if p <= 0:
return module
# supported modules
assert isinstance(module, (nn.Linear, nn.Embedding, nn.Conv2d))
# test whether module.weight has the right sizes wrt block_size
is_conv = module.weight.ndim == 4
# 2D matrix
if not is_conv:
assert (
module.weight.size(1) % block_size == 0
), "Input features must be a multiple of block sizes"
# 4D matrix
else:
# 1x1 convolutions
if module.kernel_size == (1, 1):
assert (
module.in_channels % block_size == 0
), "Input channels must be a multiple of block sizes"
# regular convolutions
else:
k = module.kernel_size[0] * module.kernel_size[1]
assert k % block_size == 0, "Kernel size must be a multiple of block size"
def _forward_pre_hook(mod, input):
# no noise for evaluation
if mod.training:
if not is_conv:
# gather weight and sizes
weight = mod.weight
in_features = weight.size(1)
out_features = weight.size(0)
# split weight matrix into blocks and randomly drop selected blocks
mask = torch.zeros(
in_features // block_size * out_features, device=weight.device
)
mask.bernoulli_(p)
mask = mask.repeat_interleave(block_size, -1).view(-1, in_features)
else:
# gather weight and sizes
weight = mod.weight
in_channels = mod.in_channels
out_channels = mod.out_channels
# split weight matrix into blocks and randomly drop selected blocks
if mod.kernel_size == (1, 1):
mask = torch.zeros(
int(in_channels // block_size * out_channels),
device=weight.device,
)
mask.bernoulli_(p)
mask = mask.repeat_interleave(block_size, -1).view(-1, in_channels)
else:
mask = torch.zeros(
weight.size(0), weight.size(1), device=weight.device
)
mask.bernoulli_(p)
mask = (
mask.unsqueeze(2)
.unsqueeze(3)
.repeat(1, 1, mod.kernel_size[0], mod.kernel_size[1])
)
# scale weights and apply mask
mask = mask.to(
torch.bool
) # x.bool() is not currently supported in TorchScript
s = 1 / (1 - p)
mod.weight.data = s * weight.masked_fill(mask, 0)
module.register_forward_pre_hook(_forward_pre_hook)
return module
class MultiheadAttention(nn.Module):
"""Multi-headed attention.
See "Attention Is All You Need" 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,
has_relative_attention_bias=False,
num_buckets=32,
max_distance=128,
gru_rel_pos=False,
rescale_init=False,
):
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_module = nn.Dropout(dropout)
self.has_relative_attention_bias = has_relative_attention_bias
self.num_buckets = num_buckets
self.max_distance = max_distance
if self.has_relative_attention_bias:
self.relative_attention_bias = nn.Embedding(num_buckets, num_heads)
self.head_dim = embed_dim // num_heads
self.q_head_dim = self.head_dim
self.k_head_dim = self.head_dim
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"
)
k_bias = True
if rescale_init:
k_bias = False
k_embed_dim = embed_dim
q_embed_dim = embed_dim
self.k_proj = quant_noise(
nn.Linear(self.kdim, k_embed_dim, bias=k_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, q_embed_dim, bias=bias), q_noise, qn_block_size
)
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.gru_rel_pos = gru_rel_pos
if self.gru_rel_pos:
self.grep_linear = nn.Linear(self.q_head_dim, 8)
self.grep_a = nn.Parameter(torch.ones(1, num_heads, 1, 1))
self.reset_parameters()
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))
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)
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)
if self.has_relative_attention_bias:
nn.init.xavier_normal_(self.relative_attention_bias.weight)
def _relative_positions_bucket(self, relative_positions, bidirectional=True):
num_buckets = self.num_buckets
max_distance = self.max_distance
relative_buckets = 0
if bidirectional:
num_buckets = num_buckets // 2
relative_buckets += (relative_positions > 0).to(torch.long) * num_buckets
relative_positions = torch.abs(relative_positions)
else:
relative_positions = -torch.min(relative_positions, torch.zeros_like(relative_positions))
max_exact = num_buckets // 2
is_small = relative_positions < max_exact
relative_postion_if_large = max_exact + (
torch.log(relative_positions.float() / max_exact)
/ math.log(max_distance / max_exact)
* (num_buckets - max_exact)
).to(torch.long)
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_positions, relative_postion_if_large)
return relative_buckets
def compute_bias(self, query_length, key_length):
context_position = torch.arange(query_length, dtype=torch.long)[:, None]
memory_position = torch.arange(key_length, dtype=torch.long)[None, :]
relative_position = memory_position - context_position
relative_position_bucket = self._relative_positions_bucket(
relative_position,
bidirectional=True
)
relative_position_bucket = relative_position_bucket.to(self.relative_attention_bias.weight.device)
values = self.relative_attention_bias(relative_position_bucket)
values = values.permute([2, 0, 1])
return values
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,
position_bias: Optional[Tensor] = None
) -> Tuple[Tensor, Optional[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
is_tpu = query.device.type == "xla"
tgt_len, bsz, embed_dim = query.size()
src_len = tgt_len
assert embed_dim == self.embed_dim
assert list(query.size()) == [tgt_len, bsz, embed_dim]
if key is not None:
src_len, key_bsz, _ = key.size()
if not torch.jit.is_scripting():
assert key_bsz == bsz
assert value is not None
assert src_len, bsz == value.shape[:2]
if self.has_relative_attention_bias and position_bias is None:
position_bias = self.compute_bias(tgt_len, src_len)
position_bias = position_bias.unsqueeze(0).repeat(bsz, 1, 1, 1).view(bsz * self.num_heads, tgt_len, src_len)
if (
not is_tpu # don't use PyTorch version on TPUs
and incremental_state is None
and not static_kv
# A workaround for quantization to work. Otherwise JIT compilation
# treats bias in linear module as method.
and not torch.jit.is_scripting()
and self.q_head_dim == self.head_dim
):
assert key is not None and value is not None
assert attn_mask is None
attn_mask_rel_pos = None
if position_bias is not None:
attn_mask_rel_pos = position_bias
if self.gru_rel_pos:
query_layer = query.transpose(0, 1)
new_x_shape = query_layer.size()[:-1] + (self.num_heads, -1)
query_layer = query_layer.view(*new_x_shape)
query_layer = query_layer.permute(0, 2, 1, 3)
_B, _H, _L, __ = query_layer.size()
gate_a, gate_b = torch.sigmoid(self.grep_linear(query_layer).view(
_B, _H, _L, 2, 4).sum(-1, keepdim=False)).chunk(2, dim=-1)
gate_a_1 = gate_a * (gate_b * self.grep_a - 1.0) + 2.0
attn_mask_rel_pos = gate_a_1.view(bsz * self.num_heads, -1, 1) * position_bias
attn_mask_rel_pos = attn_mask_rel_pos.view((-1, tgt_len, tgt_len))
k_proj_bias = self.k_proj.bias
if k_proj_bias is None:
k_proj_bias = torch.zeros_like(self.q_proj.bias)
x, attn = F.multi_head_attention_forward(
query,
key,
value,
self.embed_dim,
self.num_heads,
torch.empty([0]),
torch.cat((self.q_proj.bias, self.k_proj.bias, self.v_proj.bias)),
self.bias_k,
self.bias_v,
self.add_zero_attn,
self.dropout_module.p,
self.out_proj.weight,
self.out_proj.bias,
self.training,
# self.training or self.dropout_module.apply_during_inference,
key_padding_mask,
need_weights,
attn_mask_rel_pos,
use_separate_proj_weight=True,
q_proj_weight=self.q_proj.weight,
k_proj_weight=self.k_proj.weight,
v_proj_weight=self.v_proj.weight,
)
return x, attn, position_bias
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 = self.k_proj(query)
v = self.v_proj(query)
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.q_head_dim)
.transpose(0, 1)
)
if k is not None:
k = (
k.contiguous()
.view(-1, bsz * self.num_heads, self.k_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)
src_len = k.size(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 = MultiheadAttention._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
assert k.size(1) == src_len
# This is part of a workaround to get around fork/join parallelism
# not supporting Optional types.
if key_padding_mask is not None and key_padding_mask.dim() == 0:
key_padding_mask = None
if key_padding_mask is not None:
assert key_padding_mask.size(0) == bsz
assert key_padding_mask.size(1) == src_len
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
)
if key_padding_mask is not None:
key_padding_mask = torch.cat(
[
key_padding_mask,
torch.zeros(key_padding_mask.size(0), 1).type_as(
key_padding_mask
),
],
dim=1,
)
attn_weights = torch.bmm(q, k.transpose(1, 2))
attn_weights = self.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)
attn_weights += attn_mask
if key_padding_mask is not None:
# don't attend to padding symbols
attn_weights = attn_weights.view(bsz, self.num_heads, tgt_len, src_len)
if not is_tpu:
attn_weights = attn_weights.masked_fill(
key_padding_mask.unsqueeze(1).unsqueeze(2).to(torch.bool),
float("-inf"),
)
else:
attn_weights = attn_weights.transpose(0, 2)
attn_weights = attn_weights.masked_fill(key_padding_mask, float("-inf"))
attn_weights = attn_weights.transpose(0, 2)
attn_weights = attn_weights.view(bsz * self.num_heads, tgt_len, src_len)
if before_softmax:
return attn_weights, v, position_bias
if position_bias is not None:
if self.gru_rel_pos == 1:
query_layer = q.view(bsz, self.num_heads, tgt_len, self.q_head_dim)
_B, _H, _L, __ = query_layer.size()
gate_a, gate_b = torch.sigmoid(self.grep_linear(query_layer).view(
_B, _H, _L, 2, 4).sum(-1, keepdim=False)).chunk(2, dim=-1)
gate_a_1 = gate_a * (gate_b * self.grep_a - 1.0) + 2.0
position_bias = gate_a_1.view(bsz * self.num_heads, -1, 1) * position_bias
position_bias = position_bias.view(attn_weights.size())
attn_weights = attn_weights + position_bias
attn_weights_float = F.softmax(
attn_weights, dim=-1
)
attn_weights = attn_weights_float.type_as(attn_weights)
attn_probs = self.dropout_module(attn_weights)
assert v is not None
attn = torch.bmm(attn_probs, v)
assert list(attn.size()) == [bsz * self.num_heads, tgt_len, self.head_dim]
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, position_bias
@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:
if src_len > prev_key_padding_mask.size(1):
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
)
else:
new_key_padding_mask = prev_key_padding_mask.float()
elif key_padding_mask is not None:
if src_len > key_padding_mask.size(1):
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 = key_padding_mask.float()
else:
new_key_padding_mask = prev_key_padding_mask
return new_key_padding_mask
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(self, attn_weights, tgt_len: int, src_len: int, bsz: int):
return attn_weights
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