File size: 3,567 Bytes
0c7479d
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
import torch
import einops

import ldm.modules.encoders.modules
import ldm.modules.attention

from transformers import logging
from ldm.modules.attention import default


def disable_verbosity():
    logging.set_verbosity_error()
    print('logging improved.')
    return


def enable_sliced_attention():
    ldm.modules.attention.CrossAttention.forward = _hacked_sliced_attentin_forward
    print('Enabled sliced_attention.')
    return


def hack_everything(clip_skip=0):
    disable_verbosity()
    ldm.modules.encoders.modules.FrozenCLIPEmbedder.forward = _hacked_clip_forward
    ldm.modules.encoders.modules.FrozenCLIPEmbedder.clip_skip = clip_skip
    print('Enabled clip hacks.')
    return


# Written by Lvmin
def _hacked_clip_forward(self, text):
    PAD = self.tokenizer.pad_token_id
    EOS = self.tokenizer.eos_token_id
    BOS = self.tokenizer.bos_token_id

    def tokenize(t):
        return self.tokenizer(t, truncation=False, add_special_tokens=False)["input_ids"]

    def transformer_encode(t):
        if self.clip_skip > 1:
            rt = self.transformer(input_ids=t, output_hidden_states=True)
            return self.transformer.text_model.final_layer_norm(rt.hidden_states[-self.clip_skip])
        else:
            return self.transformer(input_ids=t, output_hidden_states=False).last_hidden_state

    def split(x):
        return x[75 * 0: 75 * 1], x[75 * 1: 75 * 2], x[75 * 2: 75 * 3]

    def pad(x, p, i):
        return x[:i] if len(x) >= i else x + [p] * (i - len(x))

    raw_tokens_list = tokenize(text)
    tokens_list = []

    for raw_tokens in raw_tokens_list:
        raw_tokens_123 = split(raw_tokens)
        raw_tokens_123 = [[BOS] + raw_tokens_i + [EOS] for raw_tokens_i in raw_tokens_123]
        raw_tokens_123 = [pad(raw_tokens_i, PAD, 77) for raw_tokens_i in raw_tokens_123]
        tokens_list.append(raw_tokens_123)

    tokens_list = torch.IntTensor(tokens_list).to(self.device)

    feed = einops.rearrange(tokens_list, 'b f i -> (b f) i')
    y = transformer_encode(feed)
    z = einops.rearrange(y, '(b f) i c -> b (f i) c', f=3)

    return z


# Stolen from https://github.com/basujindal/stable-diffusion/blob/main/optimizedSD/splitAttention.py
def _hacked_sliced_attentin_forward(self, x, context=None, mask=None):
    h = self.heads

    q = self.to_q(x)
    context = default(context, x)
    k = self.to_k(context)
    v = self.to_v(context)
    del context, x

    q, k, v = map(lambda t: einops.rearrange(t, 'b n (h d) -> (b h) n d', h=h), (q, k, v))

    limit = k.shape[0]
    att_step = 1
    q_chunks = list(torch.tensor_split(q, limit // att_step, dim=0))
    k_chunks = list(torch.tensor_split(k, limit // att_step, dim=0))
    v_chunks = list(torch.tensor_split(v, limit // att_step, dim=0))

    q_chunks.reverse()
    k_chunks.reverse()
    v_chunks.reverse()
    sim = torch.zeros(q.shape[0], q.shape[1], v.shape[2], device=q.device)
    del k, q, v
    for i in range(0, limit, att_step):
        q_buffer = q_chunks.pop()
        k_buffer = k_chunks.pop()
        v_buffer = v_chunks.pop()
        sim_buffer = torch.einsum('b i d, b j d -> b i j', q_buffer, k_buffer) * self.scale

        del k_buffer, q_buffer
        # attention, what we cannot get enough of, by chunks

        sim_buffer = sim_buffer.softmax(dim=-1)

        sim_buffer = torch.einsum('b i j, b j d -> b i d', sim_buffer, v_buffer)
        del v_buffer
        sim[i:i + att_step, :, :] = sim_buffer

        del sim_buffer
    sim = einops.rearrange(sim, '(b h) n d -> b n (h d)', h=h)
    return self.to_out(sim)