Key-value caching
Browse files- modeling_nort5.py +209 -97
modeling_nort5.py
CHANGED
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@@ -1,19 +1,17 @@
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from __future__ import absolute_import, division, print_function, unicode_literals
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import math
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from typing import List, Optional, Tuple, Union
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import torch
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import torch.nn as nn
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import torch.nn.functional as F
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from
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from torch.utils import checkpoint
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from configuration_nort5 import NorT5Config
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from transformers.modeling_utils import PreTrainedModel
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from transformers.activations import gelu_new
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from transformers.modeling_outputs import (
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Seq2SeqModelOutput, Seq2SeqLMOutput, BaseModelOutput
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)
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@@ -58,18 +56,37 @@ class Decoder(nn.Module):
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layer.mlp.mlp[1].weight.data *= math.sqrt(1.0 / (2.0 * (1 + i)))
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layer.mlp.mlp[-2].weight.data *= math.sqrt(1.0 / (2.0 * (1 + i)))
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self_relative_embedding = self.self_relative_embedding()
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cross_relative_embedding = self.cross_relative_embedding()
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torch.
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class MaskClassifier(nn.Module):
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@@ -95,11 +112,11 @@ class MaskClassifier(nn.Module):
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class EncoderLayer(nn.Module):
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def __init__(self, config):
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super().__init__()
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self.attention = Attention(config)
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self.mlp = FeedForward(config)
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def forward(self, x, padding_mask, relative_embedding):
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attention_output, attention_probs = self.attention(x, x, padding_mask, relative_embedding)
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x = x + attention_output
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x = x + self.mlp(x)
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return x, attention_probs
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@@ -108,15 +125,26 @@ class EncoderLayer(nn.Module):
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class DecoderLayer(nn.Module):
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def __init__(self, config):
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super().__init__()
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self.self_attention = Attention(config)
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self.cross_attention = Attention(config)
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self.mlp = FeedForward(config)
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def forward(self, x, autoreg_mask, encoder_output, encoder_padding_mask, self_relative_embedding, cross_relative_embedding):
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x = x + self.mlp(x)
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class GeGLU(nn.Module):
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@staticmethod
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def forward(self, x, mask, dim):
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self.dim = dim
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x = torch.softmax(x, self.dim)
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self.save_for_backward(x)
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return x
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@staticmethod
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def backward(self, grad_output):
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output, = self.saved_tensors
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return
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class Attention(nn.Module):
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def __init__(self, config):
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super().__init__()
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self.config = config
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if config.hidden_size % config.num_attention_heads != 0:
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raise ValueError(f"The hidden size {config.hidden_size} is not a multiple of the number of attention heads {config.num_attention_heads}")
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@@ -186,9 +217,9 @@ class Attention(nn.Module):
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self.pre_layer_norm = nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=False)
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self.post_layer_norm = nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=True)
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position_indices = torch.arange(
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- torch.arange(
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position_indices = self.make_log_bucket_position(position_indices, config.position_bucket_size,
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position_indices = config.position_bucket_size - 1 + position_indices
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self.register_buffer("position_indices", position_indices, persistent=True)
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@@ -215,59 +246,67 @@ class Attention(nn.Module):
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self.in_proj_v.bias.data.zero_()
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self.out_proj.bias.data.zero_()
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def
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key_len, batch_size, _ = kv.size()
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query_len, _, _ = q.size()
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if self.
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position_indices = self.make_log_bucket_position(position_indices, self.config.position_bucket_size, 512)
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position_indices = self.config.position_bucket_size - 1 + position_indices
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self.register_buffer("position_indices", position_indices.to(q.device), persistent=True)
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kv = self.pre_layer_norm(kv)
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q = self.pre_layer_norm(q)
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query = self.in_proj_q(q) # shape: [T, B, D]
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key = self.in_proj_k(kv) # shape: [T, B, D]
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value = self.in_proj_v(kv) # shape: [T, B, D]
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query_pos = self.in_proj_q(self.dropout(relative_embedding)) # shape: [2T-1, 2D]
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query_pos = F.embedding(self.position_indices[:query_len, :key_len], query_pos) # shape: [T, T, 2D]
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query_pos = query_pos.view(query_len, key_len, self.num_heads, self.head_size)
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key_pos = self.in_proj_k(self.dropout(relative_embedding)) # shape: [2T-1, 2D]
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key_pos = F.embedding(self.position_indices[:query_len, :key_len], key_pos) # shape: [T, T, 2D]
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key_pos = key_pos.view(query_len, key_len, self.num_heads, self.head_size)
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query = query.reshape(query_len, batch_size * self.num_heads, self.head_size).transpose(0, 1)
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key = key.reshape(key_len, batch_size * self.num_heads, self.head_size).transpose(0, 1)
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value = value.view(key_len, batch_size * self.num_heads, self.head_size).transpose(0, 1)
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attention_scores = torch.bmm(query, key.transpose(1, 2) * self.scale)
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attention_scores = attention_scores.view(batch_size, self.num_heads, query_len, key_len)
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attention_scores.add_(
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attention_scores.add_(
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def compute_output(self, attention_probs, value):
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attention_probs = self.dropout(attention_probs)
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context = torch.bmm(attention_probs.flatten(0, 1), value) # shape: [B*H, Q, D]
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context = context.transpose(0, 1).reshape(context.size(1), -1, self.hidden_size) # shape: [Q, B, H*D]
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context = self.out_proj(context)
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context = self.post_layer_norm(context)
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context = self.dropout(context)
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return context
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attention_scores, value = self.compute_attention_scores(q, kv, relative_embedding)
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attention_probs = MaskedSoftmax.apply(attention_scores, attention_mask, -1)
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return self.compute_output(attention_probs, value), attention_probs.detach()
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class WordEmbedding(nn.Module):
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@@ -348,8 +387,8 @@ class NorT5Model(NorT5PreTrainedModel):
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return self.get_encoder_output
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def get_decoder(self):
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return self.
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def set_decoder_special_tokens(self, target_id):
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target_id.masked_fill_(target_id == self.cls_token_id, self.bos_token_id)
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target_id.masked_fill_(target_id == self.sep_token_id, self.eos_token_id)
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@@ -359,12 +398,13 @@ class NorT5Model(NorT5PreTrainedModel):
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shifted_input_ids = input_ids.new_zeros(input_ids.shape)
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shifted_input_ids[..., 1:] = input_ids[..., :-1].clone()
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shifted_input_ids[..., 0] = self.bos_token_id
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return shifted_input_ids
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def get_encoder_output(
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self,
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input_ids:
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attention_mask: Optional[torch.Tensor] = None,
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output_hidden_states: Optional[bool] = None,
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output_attentions: Optional[bool] = None,
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]
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if not return_dict:
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return
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return BaseModelOutput(
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last_hidden_state=last_layer,
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hidden_states=contextualized_embeddings,
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attentions=attention_probs
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)
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def get_decoder_output(
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self,
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):
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batch_size, seq_length, _ = encoder_output.shape
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device = target_ids.device
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attention_mask = ~attention_mask.bool()
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attention_mask = attention_mask.unsqueeze(1).unsqueeze(2)
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self.embedding(target_ids.t()),
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encoder_output.transpose(0, 1),
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attention_mask
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def forward(
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self,
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attention_mask: Optional[torch.FloatTensor] = None,
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decoder_input_ids: Optional[torch.LongTensor] = None,
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decoder_attention_mask: Optional[torch.BoolTensor] = None,
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):
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return_dict = return_dict if return_dict is not None else self.config.use_return_dict
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decoder_input_ids = self.set_decoder_special_tokens(decoder_input_ids)
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encoder_outputs
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if not return_dict:
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return
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return Seq2SeqModelOutput(
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last_hidden_state=decoder_outputs,
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past_key_values=
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decoder_hidden_states=
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decoder_attentions=
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cross_attentions=
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encoder_last_hidden_state=encoder_outputs,
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encoder_hidden_states=
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encoder_attentions=
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)
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output_hidden_states: Optional[bool] = None,
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return_dict: Optional[bool] = None,
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):
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use_cache = False
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return_dict = return_dict if return_dict is not None else self.config.use_return_dict
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if encoder_outputs is None:
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encoder_outputs = self.get_encoder_output(
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if labels is not None:
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labels = self.set_decoder_special_tokens(labels)
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elif decoder_input_ids is not None:
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decoder_input_ids = self.set_decoder_special_tokens(decoder_input_ids)
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decoder_outputs = self.get_decoder_output(
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loss = None
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if labels is not None:
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loss = loss_fct(lm_logits.flatten(0, 1), labels.flatten())
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if not return_dict:
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output = (lm_logits,) + encoder_outputs
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return ((loss,) + output) if loss is not None else output
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return Seq2SeqLMOutput(
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loss=loss,
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logits=lm_logits,
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encoder_last_hidden_state=encoder_outputs.last_hidden_state,
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encoder_hidden_states=encoder_outputs.hidden_states,
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encoder_attentions=encoder_outputs.attentions,
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encoder_outputs=None,
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**kwargs,
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):
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return {
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"decoder_input_ids": input_ids,
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"past_key_values": past_key_values,
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reordered_layer_past_states = ()
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for layer_past_state in layer_past_states:
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# need to set correct `past` for each of the four key / value states
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)
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assert reordered_layer_past_states[0].shape == layer_past_states[0].shape
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assert len(reordered_layer_past_states) == len(layer_past_states)
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return_dict = return_dict if return_dict is not None else self.config.use_return_dict
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return self.get_encoder_output(
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import math
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from typing import List, Optional, Tuple, Union
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import torch
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import torch.nn as nn
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import torch.nn.functional as F
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from transformers.pytorch_utils import softmax_backward_data
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from torch.utils import checkpoint
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from configuration_nort5 import NorT5Config
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from transformers.modeling_utils import PreTrainedModel
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from transformers.activations import gelu_new
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from transformers.modeling_outputs import (
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Seq2SeqModelOutput, Seq2SeqLMOutput, BaseModelOutput, BaseModelOutputWithPastAndCrossAttentions
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)
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layer.mlp.mlp[1].weight.data *= math.sqrt(1.0 / (2.0 * (1 + i)))
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layer.mlp.mlp[-2].weight.data *= math.sqrt(1.0 / (2.0 * (1 + i)))
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self.activation_checkpointing = activation_checkpointing
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def forward(self, x, encoder_output, encoder_padding_mask, past_key_values=None):
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self_relative_embedding = self.self_relative_embedding()
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cross_relative_embedding = self.cross_relative_embedding()
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if past_key_values is not None:
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autoreg_mask = torch.triu(
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torch.full((x.size(0), x.size(0)), True, device=x.device),
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diagonal=1
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)
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else:
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autoreg_mask = None
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# initialize past_key_values with `None` if past does not exist
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if past_key_values is None:
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past_key_values = [None] * len(self.layers)
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hidden_states, self_attention_probs, cross_attention_probs, key_value_states = [x], [], [], []
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for layer, past_key_value in zip(self.layers, past_key_values):
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if self.activation_checkpointing:
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| 80 |
+
hidden_state, self_attention_p, cross_attention_p, key_value_state = checkpoint.checkpoint(layer, hidden_states[-1], autoreg_mask, encoder_output, encoder_padding_mask, self_relative_embedding, cross_relative_embedding, past_key_value=None)
|
| 81 |
+
else:
|
| 82 |
+
hidden_state, self_attention_p, cross_attention_p, key_value_state = layer(hidden_states[-1], autoreg_mask, encoder_output, encoder_padding_mask, self_relative_embedding, cross_relative_embedding, past_key_value=past_key_value)
|
| 83 |
+
|
| 84 |
+
hidden_states.append(hidden_state)
|
| 85 |
+
self_attention_probs.append(self_attention_p)
|
| 86 |
+
cross_attention_probs.append(cross_attention_p)
|
| 87 |
+
key_value_states.append(key_value_state)
|
| 88 |
+
|
| 89 |
+
return hidden_states, self_attention_probs, cross_attention_probs, key_value_states
|
| 90 |
|
| 91 |
|
| 92 |
class MaskClassifier(nn.Module):
|
|
|
|
| 112 |
class EncoderLayer(nn.Module):
|
| 113 |
def __init__(self, config):
|
| 114 |
super().__init__()
|
| 115 |
+
self.attention = Attention(config, is_cross_attention=False)
|
| 116 |
self.mlp = FeedForward(config)
|
| 117 |
|
| 118 |
def forward(self, x, padding_mask, relative_embedding):
|
| 119 |
+
attention_output, attention_probs, _ = self.attention(x, x, padding_mask, relative_embedding)
|
| 120 |
x = x + attention_output
|
| 121 |
x = x + self.mlp(x)
|
| 122 |
return x, attention_probs
|
|
|
|
| 125 |
class DecoderLayer(nn.Module):
|
| 126 |
def __init__(self, config):
|
| 127 |
super().__init__()
|
| 128 |
+
self.self_attention = Attention(config, is_cross_attention=False)
|
| 129 |
+
self.cross_attention = Attention(config, is_cross_attention=True)
|
| 130 |
self.mlp = FeedForward(config)
|
| 131 |
|
| 132 |
+
def forward(self, x, autoreg_mask, encoder_output, encoder_padding_mask, self_relative_embedding, cross_relative_embedding, past_key_value=None):
|
| 133 |
+
query_offset = 0
|
| 134 |
+
if past_key_value is not None:
|
| 135 |
+
self_attn_past_key_value = past_key_value[:2]
|
| 136 |
+
cross_attn_past_key_value = past_key_value[2:]
|
| 137 |
+
query_offset = self_attn_past_key_value[0].size(1)
|
| 138 |
+
else:
|
| 139 |
+
self_attn_past_key_value, cross_attn_past_key_value = None, None
|
| 140 |
+
|
| 141 |
+
x_, self_attention_probs, self_key_value_state = self.self_attention(x, x, autoreg_mask, self_relative_embedding, past_key_value=self_attn_past_key_value, query_offset=query_offset)
|
| 142 |
+
x = x + x_
|
| 143 |
+
x_, cross_attention_probs, cross_key_value_state = self.cross_attention(x, encoder_output, encoder_padding_mask, cross_relative_embedding, past_key_value=cross_attn_past_key_value, query_offset=query_offset)
|
| 144 |
+
x = x + x_
|
| 145 |
x = x + self.mlp(x)
|
| 146 |
+
|
| 147 |
+
return x, self_attention_probs, cross_attention_probs, self_key_value_state + cross_key_value_state
|
| 148 |
|
| 149 |
|
| 150 |
class GeGLU(nn.Module):
|
|
|
|
| 180 |
@staticmethod
|
| 181 |
def forward(self, x, mask, dim):
|
| 182 |
self.dim = dim
|
| 183 |
+
if mask is not None:
|
| 184 |
+
x.masked_fill_(mask, float('-inf'))
|
| 185 |
x = torch.softmax(x, self.dim)
|
| 186 |
+
if mask is not None:
|
| 187 |
+
x.masked_fill_(mask, 0.0)
|
| 188 |
self.save_for_backward(x)
|
| 189 |
return x
|
| 190 |
|
| 191 |
@staticmethod
|
| 192 |
def backward(self, grad_output):
|
| 193 |
output, = self.saved_tensors
|
| 194 |
+
input_grad = softmax_backward_data(self, grad_output, output, self.dim, output)
|
| 195 |
+
return input_grad, None, None
|
| 196 |
|
| 197 |
|
| 198 |
class Attention(nn.Module):
|
| 199 |
+
def __init__(self, config, is_cross_attention=False):
|
| 200 |
super().__init__()
|
| 201 |
|
| 202 |
self.config = config
|
| 203 |
+
self.is_cross_attention = is_cross_attention
|
| 204 |
|
| 205 |
if config.hidden_size % config.num_attention_heads != 0:
|
| 206 |
raise ValueError(f"The hidden size {config.hidden_size} is not a multiple of the number of attention heads {config.num_attention_heads}")
|
|
|
|
| 217 |
self.pre_layer_norm = nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=False)
|
| 218 |
self.post_layer_norm = nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=True)
|
| 219 |
|
| 220 |
+
position_indices = torch.arange(512, dtype=torch.long).unsqueeze(1) \
|
| 221 |
+
- torch.arange(512, dtype=torch.long).unsqueeze(0)
|
| 222 |
+
position_indices = self.make_log_bucket_position(position_indices, config.position_bucket_size, 512)
|
| 223 |
position_indices = config.position_bucket_size - 1 + position_indices
|
| 224 |
self.register_buffer("position_indices", position_indices, persistent=True)
|
| 225 |
|
|
|
|
| 246 |
self.in_proj_v.bias.data.zero_()
|
| 247 |
self.out_proj.bias.data.zero_()
|
| 248 |
|
| 249 |
+
def forward(self, q, kv, attention_mask, relative_embedding, past_key_value=None, query_offset=0):
|
| 250 |
key_len, batch_size, _ = kv.size()
|
| 251 |
query_len, _, _ = q.size()
|
| 252 |
|
| 253 |
+
if not self.is_cross_attention or past_key_value is None or past_key_value[0].size(1) != kv.size(0):
|
| 254 |
+
kv = self.pre_layer_norm(kv)
|
| 255 |
+
key = self.in_proj_k(kv) # shape: [T, B, D]
|
| 256 |
+
value = self.in_proj_v(kv) # shape: [T, B, D]
|
| 257 |
+
key = key.reshape(key_len, batch_size * self.num_heads, self.head_size).transpose(0, 1) # shape: [BxH, T, D]
|
| 258 |
+
value = value.view(key_len, batch_size * self.num_heads, self.head_size).transpose(0, 1) # shape: [BxH, T, D]
|
| 259 |
+
|
| 260 |
+
if past_key_value is not None:
|
| 261 |
+
if not self.is_cross_attention:
|
| 262 |
+
key = torch.cat([past_key_value[0], key], dim=1)
|
| 263 |
+
value = torch.cat([past_key_value[1], value], dim=1)
|
| 264 |
+
key_len = key.size(1)
|
| 265 |
+
elif past_key_value[0].size(1) == kv.size(0):
|
| 266 |
+
key = past_key_value[0]
|
| 267 |
+
value = past_key_value[1]
|
| 268 |
+
|
| 269 |
+
if self.position_indices.size(0) < max(query_len, key_len):
|
| 270 |
+
position_indices = torch.arange(max(query_len, key_len), dtype=torch.long).unsqueeze(1) \
|
| 271 |
+
- torch.arange(max(query_len, key_len), dtype=torch.long).unsqueeze(0)
|
| 272 |
position_indices = self.make_log_bucket_position(position_indices, self.config.position_bucket_size, 512)
|
| 273 |
position_indices = self.config.position_bucket_size - 1 + position_indices
|
| 274 |
self.register_buffer("position_indices", position_indices.to(q.device), persistent=True)
|
| 275 |
|
|
|
|
| 276 |
q = self.pre_layer_norm(q)
|
|
|
|
| 277 |
query = self.in_proj_q(q) # shape: [T, B, D]
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 278 |
query = query.reshape(query_len, batch_size * self.num_heads, self.head_size).transpose(0, 1)
|
|
|
|
|
|
|
| 279 |
|
| 280 |
attention_scores = torch.bmm(query, key.transpose(1, 2) * self.scale)
|
| 281 |
+
|
| 282 |
+
query_pos = self.in_proj_q(self.dropout(relative_embedding)) # shape: [2T-1, D]
|
| 283 |
+
query_pos = query_pos.view(-1, self.num_heads, self.head_size) # shape: [2T-1, H, D]
|
| 284 |
+
key_pos = self.in_proj_k(self.dropout(relative_embedding)) # shape: [2T-1, D]
|
| 285 |
+
key_pos = key_pos.view(-1, self.num_heads, self.head_size) # shape: [2T-1, H, D]
|
| 286 |
+
|
| 287 |
+
query_ = query.view(batch_size, self.num_heads, query_len, self.head_size)
|
| 288 |
+
key_ = key.view(batch_size, self.num_heads, key_len, self.head_size)
|
| 289 |
+
|
| 290 |
+
attention_c_p = torch.einsum("bhqd,khd->bhqk", query_, key_pos.squeeze(1) * self.scale)
|
| 291 |
+
attention_p_c = torch.einsum("bhkd,qhd->bhqk", key_ * self.scale, query_pos.squeeze(1))
|
| 292 |
+
position_indices = self.position_indices[query_offset:query_offset+query_len, :key_len].expand(batch_size, self.num_heads, -1, -1)
|
| 293 |
+
attention_c_p = attention_c_p.gather(3, position_indices)
|
| 294 |
+
attention_p_c = attention_p_c.gather(2, position_indices)
|
| 295 |
+
|
| 296 |
attention_scores = attention_scores.view(batch_size, self.num_heads, query_len, key_len)
|
| 297 |
+
attention_scores.add_(attention_c_p)
|
| 298 |
+
attention_scores.add_(attention_p_c)
|
| 299 |
|
| 300 |
+
attention_probs = MaskedSoftmax.apply(attention_scores, attention_mask, -1)
|
| 301 |
|
|
|
|
| 302 |
attention_probs = self.dropout(attention_probs)
|
| 303 |
context = torch.bmm(attention_probs.flatten(0, 1), value) # shape: [B*H, Q, D]
|
| 304 |
context = context.transpose(0, 1).reshape(context.size(1), -1, self.hidden_size) # shape: [Q, B, H*D]
|
| 305 |
context = self.out_proj(context)
|
| 306 |
context = self.post_layer_norm(context)
|
| 307 |
context = self.dropout(context)
|
|
|
|
| 308 |
|
| 309 |
+
return context, attention_probs.detach(), (key.detach(), value.detach())
|
|
|
|
|
|
|
|
|
|
| 310 |
|
| 311 |
|
| 312 |
class WordEmbedding(nn.Module):
|
|
|
|
| 387 |
return self.get_encoder_output
|
| 388 |
|
| 389 |
def get_decoder(self):
|
| 390 |
+
return self.get_decoder_output
|
| 391 |
+
|
| 392 |
def set_decoder_special_tokens(self, target_id):
|
| 393 |
target_id.masked_fill_(target_id == self.cls_token_id, self.bos_token_id)
|
| 394 |
target_id.masked_fill_(target_id == self.sep_token_id, self.eos_token_id)
|
|
|
|
| 398 |
shifted_input_ids = input_ids.new_zeros(input_ids.shape)
|
| 399 |
shifted_input_ids[..., 1:] = input_ids[..., :-1].clone()
|
| 400 |
shifted_input_ids[..., 0] = self.bos_token_id
|
| 401 |
+
shifted_input_ids.masked_fill_(shifted_input_ids == -100, self.pad_token_id)
|
| 402 |
|
| 403 |
return shifted_input_ids
|
| 404 |
|
| 405 |
def get_encoder_output(
|
| 406 |
self,
|
| 407 |
+
input_ids: torch.Tensor = None,
|
| 408 |
attention_mask: Optional[torch.Tensor] = None,
|
| 409 |
output_hidden_states: Optional[bool] = None,
|
| 410 |
output_attentions: Optional[bool] = None,
|
|
|
|
| 434 |
]
|
| 435 |
|
| 436 |
if not return_dict:
|
| 437 |
+
return (
|
| 438 |
+
last_layer,
|
| 439 |
+
*([contextualized_embeddings] if output_hidden_states else []),
|
| 440 |
+
*([attention_probs] if output_attentions else [])
|
| 441 |
+
)
|
| 442 |
+
|
| 443 |
return BaseModelOutput(
|
| 444 |
last_hidden_state=last_layer,
|
| 445 |
+
hidden_states=contextualized_embeddings if output_hidden_states else None,
|
| 446 |
+
attentions=attention_probs if output_attentions else None
|
| 447 |
)
|
| 448 |
|
| 449 |
def get_decoder_output(
|
| 450 |
+
self,
|
| 451 |
+
target_ids: torch.Tensor = None,
|
| 452 |
+
encoder_output: torch.Tensor = None,
|
| 453 |
+
attention_mask: Optional[torch.Tensor] = None,
|
| 454 |
+
past_key_values: Optional[Tuple[Tuple[torch.FloatTensor]]] = None,
|
| 455 |
+
use_cache: Optional[bool] = None,
|
| 456 |
+
output_hidden_states: Optional[bool] = None,
|
| 457 |
+
output_attentions: Optional[bool] = None,
|
| 458 |
+
return_dict = False
|
| 459 |
):
|
| 460 |
batch_size, seq_length, _ = encoder_output.shape
|
| 461 |
device = target_ids.device
|
|
|
|
| 466 |
attention_mask = ~attention_mask.bool()
|
| 467 |
attention_mask = attention_mask.unsqueeze(1).unsqueeze(2)
|
| 468 |
|
| 469 |
+
hidden_states, self_attention_p, cross_attention_p, key_value_states = self.decoder(
|
| 470 |
self.embedding(target_ids.t()),
|
| 471 |
encoder_output.transpose(0, 1),
|
| 472 |
+
attention_mask,
|
| 473 |
+
past_key_values
|
| 474 |
+
)
|
| 475 |
+
|
| 476 |
+
hidden_states = [e.transpose(0, 1) for e in hidden_states]
|
| 477 |
+
last_layer = hidden_states[-1]
|
| 478 |
+
hidden_states = [hidden_states[0]] + [
|
| 479 |
+
hidden_states[i] - hidden_states[i - 1]
|
| 480 |
+
for i in range(1, len(hidden_states))
|
| 481 |
+
]
|
| 482 |
+
|
| 483 |
+
if not return_dict:
|
| 484 |
+
return (
|
| 485 |
+
last_layer,
|
| 486 |
+
*([key_value_states] if use_cache else []),
|
| 487 |
+
*([hidden_states] if output_hidden_states else []),
|
| 488 |
+
*([self_attention_p] if output_attentions else []),
|
| 489 |
+
*([cross_attention_p] if output_attentions else []),
|
| 490 |
+
)
|
| 491 |
+
|
| 492 |
+
return BaseModelOutputWithPastAndCrossAttentions(
|
| 493 |
+
last_hidden_state=last_layer,
|
| 494 |
+
past_key_values=key_value_states if use_cache else None,
|
| 495 |
+
hidden_states=hidden_states if output_hidden_states else None,
|
| 496 |
+
attentions=self_attention_p if output_attentions else None,
|
| 497 |
+
cross_attentions=cross_attention_p if output_attentions else None
|
| 498 |
+
)
|
| 499 |
+
|
| 500 |
|
| 501 |
def forward(
|
| 502 |
self,
|
|
|
|
| 504 |
attention_mask: Optional[torch.FloatTensor] = None,
|
| 505 |
decoder_input_ids: Optional[torch.LongTensor] = None,
|
| 506 |
decoder_attention_mask: Optional[torch.BoolTensor] = None,
|
| 507 |
+
encoder_outputs: Optional[Tuple[Tuple[torch.FloatTensor]]] = None,
|
| 508 |
+
past_key_values: Optional[Tuple[Tuple[torch.FloatTensor]]] = None,
|
| 509 |
+
use_cache: Optional[bool] = None,
|
| 510 |
+
output_attentions: Optional[bool] = None,
|
| 511 |
+
output_hidden_states: Optional[bool] = None,
|
| 512 |
+
return_dict: Optional[bool] = None
|
| 513 |
):
|
| 514 |
|
| 515 |
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
|
| 516 |
|
| 517 |
decoder_input_ids = self.set_decoder_special_tokens(decoder_input_ids)
|
| 518 |
|
| 519 |
+
if encoder_outputs is None:
|
| 520 |
+
encoder_outputs = self.get_encoder_output(
|
| 521 |
+
input_ids, attention_mask, output_hidden_states, output_attentions, return_dict
|
| 522 |
+
)
|
| 523 |
+
elif return_dict and not isinstance(encoder_outputs, BaseModelOutput):
|
| 524 |
+
encoder_outputs = BaseModelOutput(
|
| 525 |
+
last_hidden_state=encoder_outputs[0],
|
| 526 |
+
hidden_states=encoder_outputs[1] if len(encoder_outputs) > 1 else None,
|
| 527 |
+
attentions=encoder_outputs[2] if len(encoder_outputs) > 2 else None,
|
| 528 |
+
)
|
| 529 |
+
|
| 530 |
+
decoder_outputs = self.get_decoder_output(
|
| 531 |
+
decoder_input_ids, encoder_outputs[0], attention_mask, past_key_values, use_cache, output_hidden_states, output_attentions, return_dict
|
| 532 |
+
)
|
| 533 |
|
| 534 |
if not return_dict:
|
| 535 |
+
return decoder_outputs + encoder_outputs
|
| 536 |
+
|
| 537 |
return Seq2SeqModelOutput(
|
| 538 |
+
last_hidden_state=decoder_outputs.last_hidden_state,
|
| 539 |
+
past_key_values=decoder_outputs.past_key_values,
|
| 540 |
+
decoder_hidden_states=decoder_outputs.hidden_states,
|
| 541 |
+
decoder_attentions=decoder_outputs.attentions,
|
| 542 |
+
cross_attentions=decoder_outputs.cross_attentions,
|
| 543 |
+
encoder_last_hidden_state=encoder_outputs.last_hidden_state,
|
| 544 |
+
encoder_hidden_states=encoder_outputs.hidden_states,
|
| 545 |
+
encoder_attentions=encoder_outputs.attentions,
|
| 546 |
)
|
| 547 |
|
| 548 |
|
|
|
|
| 570 |
output_hidden_states: Optional[bool] = None,
|
| 571 |
return_dict: Optional[bool] = None,
|
| 572 |
):
|
| 573 |
+
use_cache = use_cache if use_cache is not None else self.config.use_cache
|
|
|
|
| 574 |
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
|
| 575 |
|
| 576 |
if encoder_outputs is None:
|
| 577 |
+
encoder_outputs = self.get_encoder_output(
|
| 578 |
+
input_ids, attention_mask, output_hidden_states, output_attentions, return_dict
|
| 579 |
+
)
|
| 580 |
+
elif return_dict and not isinstance(encoder_outputs, BaseModelOutput):
|
| 581 |
+
encoder_outputs = BaseModelOutput(
|
| 582 |
+
last_hidden_state=encoder_outputs[0],
|
| 583 |
+
hidden_states=encoder_outputs[1] if len(encoder_outputs) > 1 else None,
|
| 584 |
+
attentions=encoder_outputs[2] if len(encoder_outputs) > 2 else None,
|
| 585 |
+
)
|
| 586 |
|
| 587 |
if labels is not None:
|
| 588 |
labels = self.set_decoder_special_tokens(labels)
|
|
|
|
| 592 |
elif decoder_input_ids is not None:
|
| 593 |
decoder_input_ids = self.set_decoder_special_tokens(decoder_input_ids)
|
| 594 |
|
| 595 |
+
decoder_outputs = self.get_decoder_output(
|
| 596 |
+
decoder_input_ids, encoder_outputs[0], attention_mask, past_key_values, use_cache, output_hidden_states, output_attentions, return_dict
|
| 597 |
+
)
|
| 598 |
+
lm_logits = self.classifier(decoder_outputs[0])
|
| 599 |
|
| 600 |
loss = None
|
| 601 |
if labels is not None:
|
| 602 |
+
labels.masked_fill_(labels == self.pad_token_id, -100)
|
| 603 |
+
loss_fct = nn.CrossEntropyLoss(ignore_index=-100)
|
| 604 |
loss = loss_fct(lm_logits.flatten(0, 1), labels.flatten())
|
| 605 |
|
| 606 |
if not return_dict:
|
| 607 |
+
output = (lm_logits,) + decoder_outputs[1:] + encoder_outputs
|
| 608 |
return ((loss,) + output) if loss is not None else output
|
| 609 |
|
| 610 |
return Seq2SeqLMOutput(
|
| 611 |
loss=loss,
|
| 612 |
logits=lm_logits,
|
| 613 |
+
past_key_values=decoder_outputs.past_key_values,
|
| 614 |
+
decoder_hidden_states=decoder_outputs.hidden_states,
|
| 615 |
+
decoder_attentions=decoder_outputs.attentions,
|
| 616 |
+
cross_attentions=decoder_outputs.cross_attentions,
|
| 617 |
encoder_last_hidden_state=encoder_outputs.last_hidden_state,
|
| 618 |
encoder_hidden_states=encoder_outputs.hidden_states,
|
| 619 |
encoder_attentions=encoder_outputs.attentions,
|
|
|
|
| 631 |
encoder_outputs=None,
|
| 632 |
**kwargs,
|
| 633 |
):
|
| 634 |
+
if past_key_values is not None:
|
| 635 |
+
input_ids = input_ids[:, -1:]
|
| 636 |
+
|
| 637 |
return {
|
| 638 |
"decoder_input_ids": input_ids,
|
| 639 |
"past_key_values": past_key_values,
|
|
|
|
| 662 |
reordered_layer_past_states = ()
|
| 663 |
for layer_past_state in layer_past_states:
|
| 664 |
# need to set correct `past` for each of the four key / value states
|
| 665 |
+
layer_past_state = layer_past_state.unflatten(0, (-1, self.config.num_attention_heads))
|
| 666 |
+
layer_past_state = layer_past_state.index_select(0, beam_idx.to(layer_past_state.device))
|
| 667 |
+
layer_past_state = layer_past_state.flatten(0, 1)
|
| 668 |
+
reordered_layer_past_states = reordered_layer_past_states + (layer_past_state,)
|
| 669 |
|
| 670 |
assert reordered_layer_past_states[0].shape == layer_past_states[0].shape
|
| 671 |
assert len(reordered_layer_past_states) == len(layer_past_states)
|
|
|
|
| 688 |
):
|
| 689 |
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
|
| 690 |
|
| 691 |
+
return self.get_encoder_output(
|
| 692 |
+
input_ids, attention_mask, output_hidden_states, output_attentions, return_dict=return_dict
|
| 693 |
+
)
|