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import torch |
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import torch.nn.functional as F |
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import torch.utils.checkpoint as checkpoint |
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from torch import Tensor, nn |
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from torchvision.ops.boxes import nms |
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from transformers import BertConfig, BertModel, BertPreTrainedModel |
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from transformers.modeling_outputs import BaseModelOutputWithPoolingAndCrossAttentions |
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class BertModelWarper(nn.Module): |
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def __init__(self, bert_model): |
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super().__init__() |
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self.config = bert_model.config |
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self.embeddings = bert_model.embeddings |
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self.encoder = bert_model.encoder |
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self.pooler = bert_model.pooler |
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self.get_extended_attention_mask = bert_model.get_extended_attention_mask |
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self.invert_attention_mask = bert_model.invert_attention_mask |
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self.get_head_mask = bert_model.get_head_mask |
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def forward( |
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self, |
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input_ids=None, |
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attention_mask=None, |
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token_type_ids=None, |
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position_ids=None, |
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head_mask=None, |
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inputs_embeds=None, |
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encoder_hidden_states=None, |
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encoder_attention_mask=None, |
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past_key_values=None, |
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use_cache=None, |
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output_attentions=None, |
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output_hidden_states=None, |
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return_dict=None, |
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): |
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r""" |
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encoder_hidden_states (:obj:`torch.FloatTensor` of shape :obj:`(batch_size, sequence_length, hidden_size)`, `optional`): |
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Sequence of hidden-states at the output of the last layer of the encoder. Used in the cross-attention if |
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the model is configured as a decoder. |
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encoder_attention_mask (:obj:`torch.FloatTensor` of shape :obj:`(batch_size, sequence_length)`, `optional`): |
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Mask to avoid performing attention on the padding token indices of the encoder input. This mask is used in |
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the cross-attention if the model is configured as a decoder. Mask values selected in ``[0, 1]``: |
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- 1 for tokens that are **not masked**, |
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- 0 for tokens that are **masked**. |
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past_key_values (:obj:`tuple(tuple(torch.FloatTensor))` of length :obj:`config.n_layers` with each tuple having 4 tensors of shape :obj:`(batch_size, num_heads, sequence_length - 1, embed_size_per_head)`): |
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Contains precomputed key and value hidden states of the attention blocks. Can be used to speed up decoding. |
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If :obj:`past_key_values` are used, the user can optionally input only the last :obj:`decoder_input_ids` |
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(those that don't have their past key value states given to this model) of shape :obj:`(batch_size, 1)` |
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instead of all :obj:`decoder_input_ids` of shape :obj:`(batch_size, sequence_length)`. |
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use_cache (:obj:`bool`, `optional`): |
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If set to :obj:`True`, :obj:`past_key_values` key value states are returned and can be used to speed up |
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decoding (see :obj:`past_key_values`). |
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""" |
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output_attentions = ( |
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output_attentions if output_attentions is not None else self.config.output_attentions |
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) |
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output_hidden_states = ( |
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output_hidden_states |
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if output_hidden_states is not None |
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else self.config.output_hidden_states |
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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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if self.config.is_decoder: |
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use_cache = use_cache if use_cache is not None else self.config.use_cache |
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else: |
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use_cache = False |
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if input_ids is not None and inputs_embeds is not None: |
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raise ValueError("You cannot specify both input_ids and inputs_embeds at the same time") |
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elif input_ids is not None: |
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input_shape = input_ids.size() |
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batch_size, seq_length = input_shape |
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elif inputs_embeds is not None: |
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input_shape = inputs_embeds.size()[:-1] |
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batch_size, seq_length = input_shape |
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else: |
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raise ValueError("You have to specify either input_ids or inputs_embeds") |
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device = input_ids.device if input_ids is not None else inputs_embeds.device |
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past_key_values_length = ( |
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past_key_values[0][0].shape[2] if past_key_values is not None else 0 |
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) |
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if attention_mask is None: |
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attention_mask = torch.ones( |
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((batch_size, seq_length + past_key_values_length)), device=device |
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) |
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if token_type_ids is None: |
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token_type_ids = torch.zeros(input_shape, dtype=torch.long, device=device) |
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extended_attention_mask: torch.Tensor = self.get_extended_attention_mask( |
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attention_mask, input_shape, device |
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) |
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if self.config.is_decoder and encoder_hidden_states is not None: |
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encoder_batch_size, encoder_sequence_length, _ = encoder_hidden_states.size() |
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encoder_hidden_shape = (encoder_batch_size, encoder_sequence_length) |
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if encoder_attention_mask is None: |
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encoder_attention_mask = torch.ones(encoder_hidden_shape, device=device) |
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encoder_extended_attention_mask = self.invert_attention_mask(encoder_attention_mask) |
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else: |
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encoder_extended_attention_mask = None |
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head_mask = self.get_head_mask(head_mask, self.config.num_hidden_layers) |
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embedding_output = self.embeddings( |
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input_ids=input_ids, |
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position_ids=position_ids, |
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token_type_ids=token_type_ids, |
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inputs_embeds=inputs_embeds, |
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past_key_values_length=past_key_values_length, |
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) |
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encoder_outputs = self.encoder( |
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embedding_output, |
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attention_mask=extended_attention_mask, |
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head_mask=head_mask, |
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encoder_hidden_states=encoder_hidden_states, |
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encoder_attention_mask=encoder_extended_attention_mask, |
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past_key_values=past_key_values, |
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use_cache=use_cache, |
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output_attentions=output_attentions, |
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output_hidden_states=output_hidden_states, |
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return_dict=return_dict, |
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) |
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sequence_output = encoder_outputs[0] |
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pooled_output = self.pooler(sequence_output) if self.pooler is not None else None |
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if not return_dict: |
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return (sequence_output, pooled_output) + encoder_outputs[1:] |
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return BaseModelOutputWithPoolingAndCrossAttentions( |
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last_hidden_state=sequence_output, |
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pooler_output=pooled_output, |
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past_key_values=encoder_outputs.past_key_values, |
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hidden_states=encoder_outputs.hidden_states, |
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attentions=encoder_outputs.attentions, |
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cross_attentions=encoder_outputs.cross_attentions, |
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) |
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class TextEncoderShell(nn.Module): |
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def __init__(self, text_encoder): |
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super().__init__() |
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self.text_encoder = text_encoder |
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self.config = self.text_encoder.config |
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def forward(self, **kw): |
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return self.text_encoder(**kw) |
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def generate_masks_with_special_tokens(tokenized, special_tokens_list, tokenizer): |
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"""Generate attention mask between each pair of special tokens |
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Args: |
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input_ids (torch.Tensor): input ids. Shape: [bs, num_token] |
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special_tokens_mask (list): special tokens mask. |
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Returns: |
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torch.Tensor: attention mask between each special tokens. |
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""" |
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input_ids = tokenized["input_ids"] |
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bs, num_token = input_ids.shape |
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special_tokens_mask = torch.zeros((bs, num_token), device=input_ids.device).bool() |
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for special_token in special_tokens_list: |
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special_tokens_mask |= input_ids == special_token |
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idxs = torch.nonzero(special_tokens_mask) |
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attention_mask = ( |
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torch.eye(num_token, device=input_ids.device).bool().unsqueeze(0).repeat(bs, 1, 1) |
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) |
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position_ids = torch.zeros((bs, num_token), device=input_ids.device) |
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previous_col = 0 |
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for i in range(idxs.shape[0]): |
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row, col = idxs[i] |
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if (col == 0) or (col == num_token - 1): |
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attention_mask[row, col, col] = True |
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position_ids[row, col] = 0 |
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else: |
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attention_mask[row, previous_col + 1 : col + 1, previous_col + 1 : col + 1] = True |
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position_ids[row, previous_col + 1 : col + 1] = torch.arange( |
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0, col - previous_col, device=input_ids.device |
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) |
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previous_col = col |
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return attention_mask, position_ids.to(torch.long) |
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def generate_masks_with_special_tokens_and_transfer_map(tokenized, special_tokens_list, tokenizer): |
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"""Generate attention mask between each pair of special tokens |
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Args: |
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input_ids (torch.Tensor): input ids. Shape: [bs, num_token] |
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special_tokens_mask (list): special tokens mask. |
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Returns: |
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torch.Tensor: attention mask between each special tokens. |
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""" |
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input_ids = tokenized["input_ids"] |
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bs, num_token = input_ids.shape |
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special_tokens_mask = torch.zeros((bs, num_token), device=input_ids.device).bool() |
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for special_token in special_tokens_list: |
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special_tokens_mask |= input_ids == special_token |
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idxs = torch.nonzero(special_tokens_mask) |
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attention_mask = ( |
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torch.eye(num_token, device=input_ids.device).bool().unsqueeze(0).repeat(bs, 1, 1) |
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) |
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position_ids = torch.zeros((bs, num_token), device=input_ids.device) |
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cate_to_token_mask_list = [[] for _ in range(bs)] |
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previous_col = 0 |
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for i in range(idxs.shape[0]): |
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row, col = idxs[i] |
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if (col == 0) or (col == num_token - 1): |
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attention_mask[row, col, col] = True |
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position_ids[row, col] = 0 |
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else: |
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attention_mask[row, previous_col + 1 : col + 1, previous_col + 1 : col + 1] = True |
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position_ids[row, previous_col + 1 : col + 1] = torch.arange( |
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0, col - previous_col, device=input_ids.device |
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) |
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c2t_maski = torch.zeros((num_token), device=input_ids.device).bool() |
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c2t_maski[previous_col + 1 : col] = True |
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cate_to_token_mask_list[row].append(c2t_maski) |
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previous_col = col |
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cate_to_token_mask_list = [ |
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torch.stack(cate_to_token_mask_listi, dim=0) |
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for cate_to_token_mask_listi in cate_to_token_mask_list |
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] |
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return attention_mask, position_ids.to(torch.long), cate_to_token_mask_list |
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