Martijn van Beers
Rename library directory
64ac833
from __future__ import absolute_import
import torch
from torch import nn
import torch.nn.functional as F
import math
from transformers import BertConfig
from transformers.modeling_outputs import BaseModelOutputWithPooling, BaseModelOutput
from BERT_explainability.modules.layers_ours import *
from transformers import (
BertPreTrainedModel,
PreTrainedModel,
)
ACT2FN = {
"relu": ReLU,
"tanh": Tanh,
"gelu": GELU,
}
def get_activation(activation_string):
if activation_string in ACT2FN:
return ACT2FN[activation_string]
else:
raise KeyError("function {} not found in ACT2FN mapping {}".format(activation_string, list(ACT2FN.keys())))
def compute_rollout_attention(all_layer_matrices, start_layer=0):
# adding residual consideration
num_tokens = all_layer_matrices[0].shape[1]
batch_size = all_layer_matrices[0].shape[0]
eye = torch.eye(num_tokens).expand(batch_size, num_tokens, num_tokens).to(all_layer_matrices[0].device)
all_layer_matrices = [all_layer_matrices[i] + eye for i in range(len(all_layer_matrices))]
all_layer_matrices = [all_layer_matrices[i] / all_layer_matrices[i].sum(dim=-1, keepdim=True)
for i in range(len(all_layer_matrices))]
joint_attention = all_layer_matrices[start_layer]
for i in range(start_layer+1, len(all_layer_matrices)):
joint_attention = all_layer_matrices[i].bmm(joint_attention)
return joint_attention
class BertEmbeddings(nn.Module):
"""Construct the embeddings from word, position and token_type embeddings."""
def __init__(self, config):
super().__init__()
self.word_embeddings = nn.Embedding(config.vocab_size, config.hidden_size, padding_idx=config.pad_token_id)
self.position_embeddings = nn.Embedding(config.max_position_embeddings, config.hidden_size)
self.token_type_embeddings = nn.Embedding(config.type_vocab_size, config.hidden_size)
# self.LayerNorm is not snake-cased to stick with TensorFlow model variable name and be able to load
# any TensorFlow checkpoint file
self.LayerNorm = LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.dropout = Dropout(config.hidden_dropout_prob)
# position_ids (1, len position emb) is contiguous in memory and exported when serialized
self.register_buffer("position_ids", torch.arange(config.max_position_embeddings).expand((1, -1)))
self.add1 = Add()
self.add2 = Add()
def forward(self, input_ids=None, token_type_ids=None, position_ids=None, inputs_embeds=None):
if input_ids is not None:
input_shape = input_ids.size()
else:
input_shape = inputs_embeds.size()[:-1]
seq_length = input_shape[1]
if position_ids is None:
position_ids = self.position_ids[:, :seq_length]
if token_type_ids is None:
token_type_ids = torch.zeros(input_shape, dtype=torch.long, device=self.position_ids.device)
if inputs_embeds is None:
inputs_embeds = self.word_embeddings(input_ids)
position_embeddings = self.position_embeddings(position_ids)
token_type_embeddings = self.token_type_embeddings(token_type_ids)
# embeddings = inputs_embeds + position_embeddings + token_type_embeddings
embeddings = self.add1([token_type_embeddings, position_embeddings])
embeddings = self.add2([embeddings, inputs_embeds])
embeddings = self.LayerNorm(embeddings)
embeddings = self.dropout(embeddings)
return embeddings
def relprop(self, cam, **kwargs):
cam = self.dropout.relprop(cam, **kwargs)
cam = self.LayerNorm.relprop(cam, **kwargs)
# [inputs_embeds, position_embeddings, token_type_embeddings]
(cam) = self.add2.relprop(cam, **kwargs)
return cam
class BertEncoder(nn.Module):
def __init__(self, config):
super().__init__()
self.config = config
self.layer = nn.ModuleList([BertLayer(config) for _ in range(config.num_hidden_layers)])
def forward(
self,
hidden_states,
attention_mask=None,
head_mask=None,
encoder_hidden_states=None,
encoder_attention_mask=None,
output_attentions=False,
output_hidden_states=False,
return_dict=False,
):
all_hidden_states = () if output_hidden_states else None
all_attentions = () if output_attentions else None
for i, layer_module in enumerate(self.layer):
if output_hidden_states:
all_hidden_states = all_hidden_states + (hidden_states,)
layer_head_mask = head_mask[i] if head_mask is not None else None
if getattr(self.config, "gradient_checkpointing", False):
def create_custom_forward(module):
def custom_forward(*inputs):
return module(*inputs, output_attentions)
return custom_forward
layer_outputs = torch.utils.checkpoint.checkpoint(
create_custom_forward(layer_module),
hidden_states,
attention_mask,
layer_head_mask,
)
else:
layer_outputs = layer_module(
hidden_states,
attention_mask,
layer_head_mask,
output_attentions,
)
hidden_states = layer_outputs[0]
if output_attentions:
all_attentions = all_attentions + (layer_outputs[1],)
if output_hidden_states:
all_hidden_states = all_hidden_states + (hidden_states,)
if not return_dict:
return tuple(v for v in [hidden_states, all_hidden_states, all_attentions] if v is not None)
return BaseModelOutput(
last_hidden_state=hidden_states, hidden_states=all_hidden_states, attentions=all_attentions
)
def relprop(self, cam, **kwargs):
# assuming output_hidden_states is False
for layer_module in reversed(self.layer):
cam = layer_module.relprop(cam, **kwargs)
return cam
# not adding relprop since this is only pooling at the end of the network, does not impact tokens importance
class BertPooler(nn.Module):
def __init__(self, config):
super().__init__()
self.dense = Linear(config.hidden_size, config.hidden_size)
self.activation = Tanh()
self.pool = IndexSelect()
def forward(self, hidden_states):
# We "pool" the model by simply taking the hidden state corresponding
# to the first token.
self._seq_size = hidden_states.shape[1]
# first_token_tensor = hidden_states[:, 0]
first_token_tensor = self.pool(hidden_states, 1, torch.tensor(0, device=hidden_states.device))
first_token_tensor = first_token_tensor.squeeze(1)
pooled_output = self.dense(first_token_tensor)
pooled_output = self.activation(pooled_output)
return pooled_output
def relprop(self, cam, **kwargs):
cam = self.activation.relprop(cam, **kwargs)
#print(cam.sum())
cam = self.dense.relprop(cam, **kwargs)
#print(cam.sum())
cam = cam.unsqueeze(1)
cam = self.pool.relprop(cam, **kwargs)
#print(cam.sum())
return cam
class BertAttention(nn.Module):
def __init__(self, config):
super().__init__()
self.self = BertSelfAttention(config)
self.output = BertSelfOutput(config)
self.pruned_heads = set()
self.clone = Clone()
def prune_heads(self, heads):
if len(heads) == 0:
return
heads, index = find_pruneable_heads_and_indices(
heads, self.self.num_attention_heads, self.self.attention_head_size, self.pruned_heads
)
# Prune linear layers
self.self.query = prune_linear_layer(self.self.query, index)
self.self.key = prune_linear_layer(self.self.key, index)
self.self.value = prune_linear_layer(self.self.value, index)
self.output.dense = prune_linear_layer(self.output.dense, index, dim=1)
# Update hyper params and store pruned heads
self.self.num_attention_heads = self.self.num_attention_heads - len(heads)
self.self.all_head_size = self.self.attention_head_size * self.self.num_attention_heads
self.pruned_heads = self.pruned_heads.union(heads)
def forward(
self,
hidden_states,
attention_mask=None,
head_mask=None,
encoder_hidden_states=None,
encoder_attention_mask=None,
output_attentions=False,
):
h1, h2 = self.clone(hidden_states, 2)
self_outputs = self.self(
h1,
attention_mask,
head_mask,
encoder_hidden_states,
encoder_attention_mask,
output_attentions,
)
attention_output = self.output(self_outputs[0], h2)
outputs = (attention_output,) + self_outputs[1:] # add attentions if we output them
return outputs
def relprop(self, cam, **kwargs):
# assuming that we don't ouput the attentions (outputs = (attention_output,)), self_outputs=(context_layer,)
(cam1, cam2) = self.output.relprop(cam, **kwargs)
#print(cam1.sum(), cam2.sum(), (cam1 + cam2).sum())
cam1 = self.self.relprop(cam1, **kwargs)
#print(cam1.sum(), cam2.sum(), (cam1 + cam2).sum())
return self.clone.relprop((cam1, cam2), **kwargs)
class BertSelfAttention(nn.Module):
def __init__(self, config):
super().__init__()
if config.hidden_size % config.num_attention_heads != 0 and not hasattr(config, "embedding_size"):
raise ValueError(
"The hidden size (%d) is not a multiple of the number of attention "
"heads (%d)" % (config.hidden_size, config.num_attention_heads)
)
self.num_attention_heads = config.num_attention_heads
self.attention_head_size = int(config.hidden_size / config.num_attention_heads)
self.all_head_size = self.num_attention_heads * self.attention_head_size
self.query = Linear(config.hidden_size, self.all_head_size)
self.key = Linear(config.hidden_size, self.all_head_size)
self.value = Linear(config.hidden_size, self.all_head_size)
self.dropout = Dropout(config.attention_probs_dropout_prob)
self.matmul1 = MatMul()
self.matmul2 = MatMul()
self.softmax = Softmax(dim=-1)
self.add = Add()
self.mul = Mul()
self.head_mask = None
self.attention_mask = None
self.clone = Clone()
self.attn_cam = None
self.attn = None
self.attn_gradients = None
def get_attn(self):
return self.attn
def save_attn(self, attn):
self.attn = attn
def save_attn_cam(self, cam):
self.attn_cam = cam
def get_attn_cam(self):
return self.attn_cam
def save_attn_gradients(self, attn_gradients):
self.attn_gradients = attn_gradients
def get_attn_gradients(self):
return self.attn_gradients
def transpose_for_scores(self, x):
new_x_shape = x.size()[:-1] + (self.num_attention_heads, self.attention_head_size)
x = x.view(*new_x_shape)
return x.permute(0, 2, 1, 3)
def transpose_for_scores_relprop(self, x):
return x.permute(0, 2, 1, 3).flatten(2)
def forward(
self,
hidden_states,
attention_mask=None,
head_mask=None,
encoder_hidden_states=None,
encoder_attention_mask=None,
output_attentions=False,
):
self.head_mask = head_mask
self.attention_mask = attention_mask
h1, h2, h3 = self.clone(hidden_states, 3)
mixed_query_layer = self.query(h1)
# If this is instantiated as a cross-attention module, the keys
# and values come from an encoder; the attention mask needs to be
# such that the encoder's padding tokens are not attended to.
if encoder_hidden_states is not None:
mixed_key_layer = self.key(encoder_hidden_states)
mixed_value_layer = self.value(encoder_hidden_states)
attention_mask = encoder_attention_mask
else:
mixed_key_layer = self.key(h2)
mixed_value_layer = self.value(h3)
query_layer = self.transpose_for_scores(mixed_query_layer)
key_layer = self.transpose_for_scores(mixed_key_layer)
value_layer = self.transpose_for_scores(mixed_value_layer)
# Take the dot product between "query" and "key" to get the raw attention scores.
attention_scores = self.matmul1([query_layer, key_layer.transpose(-1, -2)])
attention_scores = attention_scores / math.sqrt(self.attention_head_size)
if attention_mask is not None:
# Apply the attention mask is (precomputed for all layers in BertModel forward() function)
attention_scores = self.add([attention_scores, attention_mask])
# Normalize the attention scores to probabilities.
attention_probs = self.softmax(attention_scores)
self.save_attn(attention_probs)
attention_probs.register_hook(self.save_attn_gradients)
# This is actually dropping out entire tokens to attend to, which might
# seem a bit unusual, but is taken from the original Transformer paper.
attention_probs = self.dropout(attention_probs)
# Mask heads if we want to
if head_mask is not None:
attention_probs = attention_probs * head_mask
context_layer = self.matmul2([attention_probs, value_layer])
context_layer = context_layer.permute(0, 2, 1, 3).contiguous()
new_context_layer_shape = context_layer.size()[:-2] + (self.all_head_size,)
context_layer = context_layer.view(*new_context_layer_shape)
outputs = (context_layer, attention_probs) if output_attentions else (context_layer,)
return outputs
def relprop(self, cam, **kwargs):
# Assume output_attentions == False
cam = self.transpose_for_scores(cam)
# [attention_probs, value_layer]
(cam1, cam2) = self.matmul2.relprop(cam, **kwargs)
cam1 /= 2
cam2 /= 2
if self.head_mask is not None:
# [attention_probs, head_mask]
(cam1, _)= self.mul.relprop(cam1, **kwargs)
self.save_attn_cam(cam1)
cam1 = self.dropout.relprop(cam1, **kwargs)
cam1 = self.softmax.relprop(cam1, **kwargs)
if self.attention_mask is not None:
# [attention_scores, attention_mask]
(cam1, _) = self.add.relprop(cam1, **kwargs)
# [query_layer, key_layer.transpose(-1, -2)]
(cam1_1, cam1_2) = self.matmul1.relprop(cam1, **kwargs)
cam1_1 /= 2
cam1_2 /= 2
# query
cam1_1 = self.transpose_for_scores_relprop(cam1_1)
cam1_1 = self.query.relprop(cam1_1, **kwargs)
# key
cam1_2 = self.transpose_for_scores_relprop(cam1_2.transpose(-1, -2))
cam1_2 = self.key.relprop(cam1_2, **kwargs)
# value
cam2 = self.transpose_for_scores_relprop(cam2)
cam2 = self.value.relprop(cam2, **kwargs)
cam = self.clone.relprop((cam1_1, cam1_2, cam2), **kwargs)
return cam
class BertSelfOutput(nn.Module):
def __init__(self, config):
super().__init__()
self.dense = Linear(config.hidden_size, config.hidden_size)
self.LayerNorm = LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.dropout = Dropout(config.hidden_dropout_prob)
self.add = Add()
def forward(self, hidden_states, input_tensor):
hidden_states = self.dense(hidden_states)
hidden_states = self.dropout(hidden_states)
add = self.add([hidden_states, input_tensor])
hidden_states = self.LayerNorm(add)
return hidden_states
def relprop(self, cam, **kwargs):
cam = self.LayerNorm.relprop(cam, **kwargs)
# [hidden_states, input_tensor]
(cam1, cam2) = self.add.relprop(cam, **kwargs)
cam1 = self.dropout.relprop(cam1, **kwargs)
cam1 = self.dense.relprop(cam1, **kwargs)
return (cam1, cam2)
class BertIntermediate(nn.Module):
def __init__(self, config):
super().__init__()
self.dense = Linear(config.hidden_size, config.intermediate_size)
if isinstance(config.hidden_act, str):
self.intermediate_act_fn = ACT2FN[config.hidden_act]()
else:
self.intermediate_act_fn = config.hidden_act
def forward(self, hidden_states):
hidden_states = self.dense(hidden_states)
hidden_states = self.intermediate_act_fn(hidden_states)
return hidden_states
def relprop(self, cam, **kwargs):
cam = self.intermediate_act_fn.relprop(cam, **kwargs) # FIXME only ReLU
#print(cam.sum())
cam = self.dense.relprop(cam, **kwargs)
#print(cam.sum())
return cam
class BertOutput(nn.Module):
def __init__(self, config):
super().__init__()
self.dense = Linear(config.intermediate_size, config.hidden_size)
self.LayerNorm = LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
self.dropout = Dropout(config.hidden_dropout_prob)
self.add = Add()
def forward(self, hidden_states, input_tensor):
hidden_states = self.dense(hidden_states)
hidden_states = self.dropout(hidden_states)
add = self.add([hidden_states, input_tensor])
hidden_states = self.LayerNorm(add)
return hidden_states
def relprop(self, cam, **kwargs):
# print("in", cam.sum())
cam = self.LayerNorm.relprop(cam, **kwargs)
#print(cam.sum())
# [hidden_states, input_tensor]
(cam1, cam2)= self.add.relprop(cam, **kwargs)
# print("add", cam1.sum(), cam2.sum(), cam1.sum() + cam2.sum())
cam1 = self.dropout.relprop(cam1, **kwargs)
#print(cam1.sum())
cam1 = self.dense.relprop(cam1, **kwargs)
# print("dense", cam1.sum())
# print("out", cam1.sum() + cam2.sum(), cam1.sum(), cam2.sum())
return (cam1, cam2)
class BertLayer(nn.Module):
def __init__(self, config):
super().__init__()
self.attention = BertAttention(config)
self.intermediate = BertIntermediate(config)
self.output = BertOutput(config)
self.clone = Clone()
def forward(
self,
hidden_states,
attention_mask=None,
head_mask=None,
output_attentions=False,
):
self_attention_outputs = self.attention(
hidden_states,
attention_mask,
head_mask,
output_attentions=output_attentions,
)
attention_output = self_attention_outputs[0]
outputs = self_attention_outputs[1:] # add self attentions if we output attention weights
ao1, ao2 = self.clone(attention_output, 2)
intermediate_output = self.intermediate(ao1)
layer_output = self.output(intermediate_output, ao2)
outputs = (layer_output,) + outputs
return outputs
def relprop(self, cam, **kwargs):
(cam1, cam2) = self.output.relprop(cam, **kwargs)
# print("output", cam1.sum(), cam2.sum(), cam1.sum() + cam2.sum())
cam1 = self.intermediate.relprop(cam1, **kwargs)
# print("intermediate", cam1.sum())
cam = self.clone.relprop((cam1, cam2), **kwargs)
# print("clone", cam.sum())
cam = self.attention.relprop(cam, **kwargs)
# print("attention", cam.sum())
return cam
class BertModel(BertPreTrainedModel):
def __init__(self, config):
super().__init__(config)
self.config = config
self.embeddings = BertEmbeddings(config)
self.encoder = BertEncoder(config)
self.pooler = BertPooler(config)
self.init_weights()
def get_input_embeddings(self):
return self.embeddings.word_embeddings
def set_input_embeddings(self, value):
self.embeddings.word_embeddings = value
def forward(
self,
input_ids=None,
attention_mask=None,
token_type_ids=None,
position_ids=None,
head_mask=None,
inputs_embeds=None,
encoder_hidden_states=None,
encoder_attention_mask=None,
output_attentions=None,
output_hidden_states=None,
return_dict=None,
):
r"""
encoder_hidden_states (:obj:`torch.FloatTensor` of shape :obj:`(batch_size, sequence_length, hidden_size)`, `optional`):
Sequence of hidden-states at the output of the last layer of the encoder. Used in the cross-attention
if the model is configured as a decoder.
encoder_attention_mask (:obj:`torch.FloatTensor` of shape :obj:`(batch_size, sequence_length)`, `optional`):
Mask to avoid performing attention on the padding token indices of the encoder input. This mask
is used in the cross-attention if the model is configured as a decoder.
Mask values selected in ``[0, 1]``:
``1`` for tokens that are NOT MASKED, ``0`` for MASKED tokens.
"""
output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
output_hidden_states = (
output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
)
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
if input_ids is not None and inputs_embeds is not None:
raise ValueError("You cannot specify both input_ids and inputs_embeds at the same time")
elif input_ids is not None:
input_shape = input_ids.size()
elif inputs_embeds is not None:
input_shape = inputs_embeds.size()[:-1]
else:
raise ValueError("You have to specify either input_ids or inputs_embeds")
device = input_ids.device if input_ids is not None else inputs_embeds.device
if attention_mask is None:
attention_mask = torch.ones(input_shape, device=device)
if token_type_ids is None:
token_type_ids = torch.zeros(input_shape, dtype=torch.long, device=device)
# We can provide a self-attention mask of dimensions [batch_size, from_seq_length, to_seq_length]
# ourselves in which case we just need to make it broadcastable to all heads.
extended_attention_mask: torch.Tensor = self.get_extended_attention_mask(attention_mask, input_shape, device)
# If a 2D or 3D attention mask is provided for the cross-attention
# we need to make broadcastable to [batch_size, num_heads, seq_length, seq_length]
if self.config.is_decoder and encoder_hidden_states is not None:
encoder_batch_size, encoder_sequence_length, _ = encoder_hidden_states.size()
encoder_hidden_shape = (encoder_batch_size, encoder_sequence_length)
if encoder_attention_mask is None:
encoder_attention_mask = torch.ones(encoder_hidden_shape, device=device)
encoder_extended_attention_mask = self.invert_attention_mask(encoder_attention_mask)
else:
encoder_extended_attention_mask = None
# Prepare head mask if needed
# 1.0 in head_mask indicate we keep the head
# attention_probs has shape bsz x n_heads x N x N
# input head_mask has shape [num_heads] or [num_hidden_layers x num_heads]
# and head_mask is converted to shape [num_hidden_layers x batch x num_heads x seq_length x seq_length]
head_mask = self.get_head_mask(head_mask, self.config.num_hidden_layers)
embedding_output = self.embeddings(
input_ids=input_ids, position_ids=position_ids, token_type_ids=token_type_ids, inputs_embeds=inputs_embeds
)
encoder_outputs = self.encoder(
embedding_output,
attention_mask=extended_attention_mask,
head_mask=head_mask,
encoder_hidden_states=encoder_hidden_states,
encoder_attention_mask=encoder_extended_attention_mask,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
)
sequence_output = encoder_outputs[0]
pooled_output = self.pooler(sequence_output)
if not return_dict:
return (sequence_output, pooled_output) + encoder_outputs[1:]
return BaseModelOutputWithPooling(
last_hidden_state=sequence_output,
pooler_output=pooled_output,
hidden_states=encoder_outputs.hidden_states,
attentions=encoder_outputs.attentions,
)
def relprop(self, cam, **kwargs):
cam = self.pooler.relprop(cam, **kwargs)
# print("111111111111",cam.sum())
cam = self.encoder.relprop(cam, **kwargs)
# print("222222222222222", cam.sum())
# print("conservation: ", cam.sum())
return cam
if __name__ == '__main__':
class Config:
def __init__(self, hidden_size, num_attention_heads, attention_probs_dropout_prob):
self.hidden_size = hidden_size
self.num_attention_heads = num_attention_heads
self.attention_probs_dropout_prob = attention_probs_dropout_prob
model = BertSelfAttention(Config(1024, 4, 0.1))
x = torch.rand(2, 20, 1024)
x.requires_grad_()
model.eval()
y = model.forward(x)
relprop = model.relprop(torch.rand(2, 20, 1024), (torch.rand(2, 20, 1024),))
print(relprop[1][0].shape)