File size: 9,187 Bytes
e0b11c9
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
d75dc6d
 
e0b11c9
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
acd6966
e0b11c9
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
d75dc6d
 
 
 
 
e0b11c9
 
 
 
d75dc6d
e0b11c9
 
d75dc6d
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239

import torch.nn as nn
import torch
import numpy as np
import torch.nn.functional as F

from lm_steer.utils import set_seed
from .model_utils import find_max_subspans


punctuations = [
    '!', '"', '$', '%', '&', "'", '(', ')', '*', '+', ',', '-', '.',
    # '/', '#',
    ':', ';', '<', '=', '>', '?', '@',
    '[', '\\', ']', '^', '_', '`',
    '{', '|', '}', '~',
    '¨', '©', 'ª', '«', '¬', '®', '¯', '°', '±', '²', '³', '´', 'µ', '¶', '·',
    '¸', '¹', 'º', '»', '¼', '½', '¾',
    '\n', ' ',
]


class LMSteerBase(nn.Module):
    def evidence_words(self, prompt, comparing_steer_values,
                       truncation_length=1024, max_segments=4, max_length=10):
        if isinstance(comparing_steer_values, list):
            comparing_steer_values = \
                torch.Tensor(comparing_steer_values).to(self.device)
        if (comparing_steer_values[0] - comparing_steer_values[1]).abs().sum()\
                <= 0.2:
            return [(prompt, None)]
        tokenized = self.tokenizer(
            prompt, return_tensors="pt",
            max_length=truncation_length, truncation=True)
        input_ids = torch.LongTensor(tokenized["input_ids"]).to(self.device)
        input_ids = input_ids.expand(2, -1)
        attention_mask = torch.LongTensor(tokenized["attention_mask"]).to(
            self.device)
        attention_mask = attention_mask.expand(2, -1)
        self.steer.set_value(comparing_steer_values)
        with torch.no_grad():
            output = self.model(
                input_ids=input_ids,
                attention_mask=attention_mask,
                labels=input_ids)
        length = input_ids.shape[1]
        loss_token = F.cross_entropy(
            output.logits[:, :-1].reshape((2)*(length-1), -1),
            input_ids[:, 1:].reshape(-1),
            reduction="none"
        )
        loss_token = loss_token.reshape(2, length - 1)

        token_evidence = (- loss_token[0] + loss_token[1])
        tokens = input_ids[0]
        evidence_segments = find_max_subspans(
            token_evidence.cpu().numpy().tolist(), max_segments, max_length)[0]
        evidence_segments = [
            (_seg[0]+1, _seg[1]+1) for _seg in evidence_segments]
        start = 0
        output = []
        if len(evidence_segments) > 0:
            for _segment in evidence_segments:
                if _segment[0] > start:
                    output.append((
                        self.tokenizer.decode(tokens[start: _segment[0]]),
                        None
                    ))
                output.append((
                    self.tokenizer.decode(tokens[_segment[0]: _segment[1]]),
                    "evidence"
                ))
                start = _segment[1]
            length = tokens.shape[-1]
            if _segment[1] < length:
                output.append((
                    self.tokenizer.decode(tokens[_segment[1]: length]),
                    None
                ))
        else:
            output = [(prompt, None)]

        return output, token_evidence.tolist()

    def steer_analysis(self, prompt, steer_dim, min_value=-3, max_value=3,
                       bins=7):
        tokenized = self.tokenizer(prompt)
        input_ids = torch.LongTensor(tokenized["input_ids"]).to(self.device)
        input_ids = input_ids.expand(bins + 1, -1)
        attention_mask = torch.LongTensor(tokenized["attention_mask"]).to(
            self.device)
        attention_mask = attention_mask.expand(bins + 1, -1)
        steer_values = torch.zeros(bins+1, self.num_steers).to(self.device)
        for bin_i in range(bins):
            steer_values[bin_i, steer_dim] = (
                min_value + (max_value - min_value) / (bins - 1) * bin_i
            )
        self.steer.set_value(steer_values)
        with torch.no_grad():
            output = self.model(
                input_ids=input_ids,
                attention_mask=attention_mask,
                labels=input_ids)
        length = input_ids.shape[1]
        loss_token = F.cross_entropy(
            output.logits[:, :-1].reshape((bins+1)*(length-1), -1),
            input_ids[:, 1:].reshape(-1),
            reduction="none"
        )
        loss_token = loss_token.reshape(bins + 1, length - 1)
        loss = loss_token.mean(-1)[:-1]
        dist = ((- loss + loss.mean()) * 10).softmax(0)
        dist_list = list(zip(
            [
                min_value + (max_value - min_value) / (bins - 1) * bin_i
                for bin_i in range(bins)
            ],
            dist.tolist(),
        ))
        best_guess = loss.argmin(0)
        best_guess_value = min_value + \
            (max_value - min_value) / (bins - 1) * best_guess.item()

        token_evidence = (- loss_token[best_guess] + loss_token[-1]) * 10
        token_evidence = [0] + token_evidence.tolist()
        # tokens = self.tokenizer.convert_ids_to_tokens(input_ids[0])

        word_evidence_list = []
        start = 0
        n_tokens = len(input_ids[0])
        for token_i in range(1, n_tokens+1):
            span = self.tokenizer.decode(input_ids[0][start: token_i])
            for _punc in punctuations:
                if token_i == n_tokens or _punc in span:
                    new_span = self.tokenizer.decode(
                        input_ids[0][start: token_i-1]).strip()
                    if len(new_span) <= 1:
                        break
                    word_evidence_list.append((
                        new_span,
                        np.array(token_evidence[start: token_i-1]).mean()
                    ))
                    start = token_i - 1
                    break

        # token_evidence_list = list(zip(tokens, token_evidence))
        return best_guess_value, dist_list, word_evidence_list

    def generate(self, prompt, steer_values, min_length=20, max_length=100,
                 seed=None, num_beams=1, num_beam_groups=1, do_sample=True,
                 temperature=1, top_p=1):
        '''
        prompt: a string
        steer_values
        min_length: minimum generation length
        max_length: maximum generation length
        seed: seed for generation. None if not specified.
        '''
        if seed is not None:
            set_seed(seed)
        steer_values = torch.Tensor(steer_values).to(
            self.device)
        self.steer.set_value(steer_values[None])
        with torch.no_grad():
            inputs = self.tokenizer(
                prompt, return_tensors="pt").to(self.device)
            text = self.model.generate(
                **inputs,
                num_beams=num_beams, num_beam_groups=num_beam_groups,
                do_sample=do_sample, temperature=temperature, top_p=top_p,
                min_length=min_length, max_length=max_length,
                pad_token_id=self.tokenizer.pad_token_id,
            )
            text = self.tokenizer.decode(text[0], skip_special_tokens=True)

        return text

    def generate_low_resource(
        self, prompt, steer_values, min_length=20, max_length=100,
        seed=None, num_beams=1, num_beam_groups=1, do_sample=True,
        temperature=1, top_p=1
    ):
        '''
        prompt: a string
        steer_values
        min_length: minimum generation length
        max_length: maximum generation length
        seed: seed for generation. None if not specified.
        '''
        if seed is not None:
            set_seed(seed)
        steer_values = torch.Tensor(steer_values).to(
            self.device)
        fp16 = torch.float16
        steer_values = steer_values.to(fp16)
        self.steer.projector1.data = self.steer.projector1.to(fp16)
        self.steer.projector2.data = self.steer.projector2.to(fp16)
        self.steer.set_value(steer_values[None])
        with torch.no_grad():
            input_ids = self.tokenizer(
                prompt, return_tensors="pt").input_ids.to(self.device)
            gen_tokens = self.model.generate(
                input_ids,
                num_beams=num_beams, num_beam_groups=num_beam_groups,
                do_sample=do_sample, temperature=temperature, top_p=top_p,
                min_length=min_length, max_length=max_length,
                pad_token_id=self.tokenizer.pad_token_id)
            text = self.tokenizer.batch_decode(gen_tokens)[0]

        # recovering
        fp32 = torch.float32
        self.steer.projector1.data = self.steer.projector1.to(fp32)
        self.steer.projector2.data = self.steer.projector2.to(fp32)
        return text

    def state_dict(self):
        return self.steer.state_dict()

    def load_state_dict(self, state_dict):
        self.steer.load_state_dict(state_dict)

    def parameters(self):
        return self.steer.parameters()

    def to_device(self, device):
        self.model.to(device)
        self.device = device

    def regularization_term(self):
        return self.steer.regularization_term()

    def forward(self, input_ids, attention_mask, steer_values):
        self.steer.set_value(steer_values)
        output = self.model(
            input_ids=input_ids,
            attention_mask=attention_mask,
            labels=input_ids)
        return output