File size: 9,740 Bytes
f520676
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
from pathlib import Path

import torch
import torch.nn.functional as F
from torch import version as torch_version

from modules import shared
from modules.logging_colors import logger
from modules.models import clear_torch_cache
from modules.text_generation import get_max_prompt_length

try:
    from exllama.generator import ExLlamaGenerator
    from exllama.model import ExLlama, ExLlamaCache, ExLlamaConfig
    from exllama.tokenizer import ExLlamaTokenizer
except:
    logger.warning('exllama module failed to import. Will attempt to import from repositories/.')
    try:
        from modules.relative_imports import RelativeImport

        with RelativeImport("repositories/exllama"):
            from generator import ExLlamaGenerator
            from model import ExLlama, ExLlamaCache, ExLlamaConfig
            from tokenizer import ExLlamaTokenizer
    except:
        logger.error(
            "Could not find repositories/exllama. Please ensure that exllama"
            " (https://github.com/turboderp/exllama) is cloned inside repositories/ and is up to date."
        )
        raise


class ExllamaModel:
    def __init__(self):
        pass

    @classmethod
    def from_pretrained(self, path_to_model):

        path_to_model = Path(f'{shared.args.model_dir}') / Path(path_to_model)
        tokenizer_model_path = path_to_model / "tokenizer.model"
        model_config_path = path_to_model / "config.json"

        # Find the model checkpoint
        model_path = None
        for ext in ['.safetensors', '.pt', '.bin']:
            found = list(path_to_model.glob(f"*{ext}"))
            if len(found) > 0:
                if len(found) > 1:
                    logger.warning(f'More than one {ext} model has been found. The last one will be selected. It could be wrong.')

                model_path = found[-1]
                break

        config = ExLlamaConfig(str(model_config_path))
        config.model_path = str(model_path)
        config.max_seq_len = shared.args.max_seq_len
        config.compress_pos_emb = shared.args.compress_pos_emb
        if shared.args.gpu_split:
            config.set_auto_map(shared.args.gpu_split)
            config.gpu_peer_fix = True

        if shared.args.alpha_value > 1 and shared.args.rope_freq_base == 0:
            config.alpha_value = shared.args.alpha_value
            config.calculate_rotary_embedding_base()
        elif shared.args.rope_freq_base > 0:
            config.rotary_embedding_base = shared.args.rope_freq_base

        if torch_version.hip:
            config.rmsnorm_no_half2 = True
            config.rope_no_half2 = True
            config.matmul_no_half2 = True
            config.silu_no_half2 = True

        model = ExLlama(config)
        tokenizer = ExLlamaTokenizer(str(tokenizer_model_path))
        cache = ExLlamaCache(model)
        generator = ExLlamaGenerator(model, tokenizer, cache)

        result = self()
        result.config = config
        result.model = model
        result.cache = cache
        result.tokenizer = tokenizer
        result.generator = generator
        return result, result

    def encode(self, string, **kwargs):
        return self.tokenizer.encode(string, max_seq_len=self.model.config.max_seq_len, add_bos=True)

    def decode(self, ids, **kwargs):
        if isinstance(ids, list):
            ids = torch.tensor([ids])
        elif isinstance(ids, torch.Tensor) and ids.numel() == 1:
            ids = ids.view(1, -1)

        return self.tokenizer.decode(ids)[0]

    def get_logits(self, token_ids, **kwargs):
        self.cache.current_seq_len = 0
        if token_ids.shape[-1] > 1:
            self.model.forward(token_ids[:, :-1], self.cache, input_mask=None, preprocess_only=True)

        return self.model.forward(token_ids[:, -1:], self.cache, **kwargs).float().cpu()

    def generate_with_streaming(self, prompt, state):

        # The cache batch size must be 2 for CFG and 1 otherwise
        if state['guidance_scale'] == 1:
            if self.cache.batch_size == 2:
                del self.cache
                clear_torch_cache()
                self.cache = ExLlamaCache(self.model)
                self.generator = ExLlamaGenerator(self.model, self.tokenizer, self.cache)
        else:
            if self.cache.batch_size == 1:
                del self.cache
                clear_torch_cache()
                self.cache = ExLlamaCache(self.model, batch_size=2)
                self.generator = ExLlamaGenerator(self.model, self.tokenizer, self.cache)

        self.generator.settings.temperature = state['temperature']
        self.generator.settings.top_p = state['top_p']
        self.generator.settings.top_k = state['top_k']
        self.generator.settings.typical = state['typical_p']
        self.generator.settings.token_repetition_penalty_max = state['repetition_penalty']
        self.generator.settings.token_repetition_penalty_sustain = -1 if state['repetition_penalty_range'] <= 0 else state['repetition_penalty_range']
        if state['ban_eos_token']:
            self.generator.disallow_tokens([self.tokenizer.eos_token_id])
        else:
            self.generator.disallow_tokens(None)

        if state['custom_token_bans']:
            to_ban = [int(x) for x in state['custom_token_bans'].split(',')]
            if len(to_ban) > 0:
                self.generator.disallow_tokens(to_ban)

        # Case 1: no CFG
        if state['guidance_scale'] == 1:
            self.generator.end_beam_search()

            # Tokenizing the input
            ids = self.generator.tokenizer.encode(prompt, max_seq_len=self.model.config.max_seq_len)
            if state['add_bos_token']:
                ids = torch.cat(
                    [torch.tensor([[self.tokenizer.bos_token_id]]).to(ids.device),
                     ids], dim=1
                ).to(torch.int64)
            ids = ids[:, -get_max_prompt_length(state):]
            if state['auto_max_new_tokens']:
                max_new_tokens = state['truncation_length'] - ids.shape[-1]
            else:
                max_new_tokens = state['max_new_tokens']

            self.generator.gen_begin_reuse(ids)
            initial_len = self.generator.sequence[0].shape[0]
            has_leading_space = False

            for i in range(max_new_tokens):
                token = self.generator.gen_single_token()
                if i == 0 and self.generator.tokenizer.tokenizer.IdToPiece(int(token)).startswith('▁'):
                    has_leading_space = True

                decoded_text = self.generator.tokenizer.decode(self.generator.sequence[0][initial_len:])
                if has_leading_space:
                    decoded_text = ' ' + decoded_text

                # Check the partial unicode character
                if chr(0xfffd) in decoded_text:
                    is_last = i == max_new_tokens - 1
                    is_stopping = token.item() == self.generator.tokenizer.eos_token_id or shared.stop_everything
                    # If we are not at the end of the generation, we skip this token
                    if not (is_last or is_stopping):
                        continue

                if token.item() == self.generator.tokenizer.eos_token_id or shared.stop_everything:
                    break

                yield decoded_text

        # Case 2: CFG
        # Copied from https://github.com/turboderp/exllama/blob/master/example_cfg.py
        else:
            alpha = state['guidance_scale']
            prompts = [prompt, state['negative_prompt'] or '']

            ids, mask = self.tokenizer.encode(
                prompts,
                return_mask=True,
                max_seq_len=self.model.config.max_seq_len,
                add_bos=state['add_bos_token']
            )
            if state['auto_max_new_tokens']:
                max_new_tokens = state['truncation_length'] - ids[0].shape[-1]
            else:
                max_new_tokens = state['max_new_tokens']

            self.generator.gen_begin(ids, mask=mask)
            initial_len = self.generator.sequence[0].shape[0]
            has_leading_space = False

            for i in range(max_new_tokens):
                logits = self.model.forward(self.generator.sequence[:, -1:], self.cache, input_mask=mask)
                self.generator.apply_rep_penalty(logits)

                logits = F.log_softmax(logits, dim=-1)
                logits_mixed = alpha * logits[0] + (1 - alpha) * logits[1]

                token, _ = self.generator.sample_current(logits_mixed)
                if i == 0 and self.generator.tokenizer.tokenizer.IdToPiece(int(token)).startswith('▁'):
                    has_leading_space = True

                decoded_text = self.generator.tokenizer.decode(self.generator.sequence[0][initial_len:])
                if has_leading_space:
                    decoded_text = ' ' + decoded_text

                # Check the partial unicode character
                if chr(0xfffd) in decoded_text:
                    is_last = i == max_new_tokens - 1
                    is_stopping = token.item() == self.tokenizer.eos_token_id or shared.stop_everything
                    # If we are not at the end of the generation, we skip this token
                    if not (is_last or is_stopping):
                        continue

                yield decoded_text
                if token.item() == self.tokenizer.eos_token_id or shared.stop_everything:
                    break

                batch_token = token.repeat(2, 1)
                self.generator.gen_accept_token(batch_token)

    def generate(self, prompt, state):
        output = ''
        for output in self.generate_with_streaming(prompt, state):
            pass

        return output