stable-diffusion.cpp/src/tokenizers/gemma_tokenizer.cpp
2026-04-29 01:11:15 +08:00

192 lines
5.3 KiB
C++

#include "gemma_tokenizer.h"
#include "ggml.h"
#include "json.hpp"
#include "util.h"
#include "vocab/vocab.h"
std::string GemmaTokenizer::normalize(const std::string& text) const {
std::string normalized = text;
size_t pos = 0;
while ((pos = normalized.find(' ', pos)) != std::string::npos) {
normalized.replace(pos, 1, "\xE2\x96\x81");
pos += 3;
}
return normalized;
}
void GemmaTokenizer::load_from_merges(const std::string& merges_utf8_str, const std::string& vocab_utf8_str) {
nlohmann::json vocab;
try {
vocab = nlohmann::json::parse(vocab_utf8_str);
} catch (const nlohmann::json::parse_error&) {
GGML_ABORT("invalid vocab json str");
}
for (const auto& [key, value] : vocab.items()) {
std::u32string token = utf8_to_utf32(key);
int i = value;
encoder[token] = i;
decoder[i] = token;
}
encoder_len = static_cast<int>(vocab.size());
LOG_DEBUG("vocab size: %d", encoder_len);
std::vector<std::u32string> merges = split_utf32(merges_utf8_str);
std::vector<std::pair<std::u32string, std::u32string>> merge_pairs;
for (const auto& merge : merges) {
size_t space_pos = merge.find(' ');
merge_pairs.emplace_back(merge.substr(0, space_pos), merge.substr(space_pos + 1));
}
LOG_DEBUG("merges size %zu", merge_pairs.size());
int rank = 0;
for (const auto& merge : merge_pairs) {
bpe_ranks[merge] = rank++;
}
bpe_len = rank;
}
GemmaTokenizer::GemmaTokenizer(const std::string& merges_utf8_str, const std::string& vocab_utf8_str) {
byte_level_bpe = false;
byte_fallback = true;
add_bos_token = true;
pad_left = true;
PAD_TOKEN = "<pad>";
EOS_TOKEN = "<eos>";
BOS_TOKEN = "<bos>";
UNK_TOKEN = "<unk>";
PAD_TOKEN_ID = 0;
EOS_TOKEN_ID = 1;
BOS_TOKEN_ID = 2;
UNK_TOKEN_ID = 3;
std::vector<std::string> special_tokens_before_merge = {
PAD_TOKEN,
EOS_TOKEN,
BOS_TOKEN,
UNK_TOKEN,
"<mask>",
"[multimodal]",
};
for (int i = 0; i <= 98; i++) {
special_tokens_before_merge.push_back("<unused" + std::to_string(i) + ">");
}
special_tokens_before_merge.push_back("<start_of_turn>");
special_tokens_before_merge.push_back("<end_of_turn>");
for (int i = 1; i <= 31; i++) {
special_tokens_before_merge.push_back(std::string(i, '\n'));
}
for (int i = 2; i <= 31; i++) {
std::string whitespace_token;
for (int j = 0; j < i; j++) {
whitespace_token += "\xE2\x96\x81";
}
special_tokens_before_merge.push_back(whitespace_token);
}
std::vector<std::string> html_tokens = {
"<table>",
"<caption>",
"<thead>",
"<tbody>",
"<tfoot>",
"<tr>",
"<th>",
"<td>",
"</table>",
"</caption>",
"</thead>",
"</tbody>",
"</tfoot>",
"</tr>",
"</th>",
"</td>",
"<h1>",
"<h2>",
"<h3>",
"<h4>",
"<h5>",
"<h6>",
"<blockquote>",
"</h1>",
"</h2>",
"</h3>",
"</h4>",
"</h5>",
"</h6>",
"</blockquote>",
"<strong>",
"<em>",
"<b>",
"<i>",
"<u>",
"<s>",
"<sub>",
"<sup>",
"<code>",
"</strong>",
"</em>",
"</b>",
"</i>",
"</u>",
"</s>",
"</sub>",
"</sup>",
"</code>",
"<a>",
"<html>",
"<body>",
"<img>",
"<span>",
"<bbox>",
"<ul>",
"<li>",
"<div>",
"<iframe>",
"<footer>",
"</a>",
"</html>",
"</body>",
"</img>",
"</span>",
"</bbox>",
"</ul>",
"</li>",
"</div>",
"</iframe>",
"</footer>",
};
special_tokens_before_merge.insert(special_tokens_before_merge.end(),
html_tokens.begin(),
html_tokens.end());
for (int i = 0; i <= 0xFF; i++) {
char hex_buf[16];
snprintf(hex_buf, sizeof(hex_buf), "<0x%02X>", i);
special_tokens_before_merge.push_back(hex_buf);
}
std::vector<std::string> special_tokens_after_merge = {
"<start_of_image>",
"<end_of_image>",
};
for (int i = 1; i <= 31; i++) {
special_tokens_after_merge.insert(special_tokens_after_merge.begin() + i - 1,
std::string(i, '\t'));
}
for (int i = 99; i <= 6241; i++) {
special_tokens_after_merge.push_back("<unused" + std::to_string(i) + ">");
}
special_tokens_after_merge.push_back("<image_soft_token>");
special_tokens = special_tokens_before_merge;
special_tokens.insert(special_tokens.end(),
special_tokens_after_merge.begin(),
special_tokens_after_merge.end());
if (merges_utf8_str.size() > 0 && vocab_utf8_str.size() > 0) {
load_from_merges(merges_utf8_str, vocab_utf8_str);
} else {
load_from_merges(load_gemma_merges(), load_gemma_vocab_json());
}
}