diff options
Diffstat (limited to 'llama.cpp')
| -rw-r--r-- | llama.cpp | 117 |
1 files changed, 117 insertions, 0 deletions
@@ -12508,6 +12508,123 @@ int32_t llama_token_to_piece(const struct llama_model * model, llama_token token return 0; } +// trim whitespace from the beginning and end of a string +static std::string trim(const std::string & str) { + size_t start = 0; + size_t end = str.size(); + while (start < end && isspace(str[start])) { + start += 1; + } + while (end > start && isspace(str[end - 1])) { + end -= 1; + } + return str.substr(start, end - start); +} + +// Simple version of "llama_apply_chat_template" that only works with strings +// This function uses heuristic checks to determine commonly used template. It is not a jinja parser. +static int32_t llama_chat_apply_template_internal( + const std::string & tmpl, + const std::vector<const llama_chat_message *> & chat, + std::string & dest, bool add_ass) { + // Taken from the research: https://github.com/ggerganov/llama.cpp/issues/5527 + std::stringstream ss; + if (tmpl.find("<|im_start|>") != std::string::npos) { + // chatml template + for (auto message : chat) { + ss << "<|im_start|>" << message->role << "\n" << message->content << "<|im_end|>\n"; + } + if (add_ass) { + ss << "<|im_start|>assistant\n"; + } + } else if (tmpl.find("[INST]") != std::string::npos) { + // llama2 template and its variants + // [variant] support system message + bool support_system_message = tmpl.find("<<SYS>>") != std::string::npos; + // [variant] space before + after response + bool space_around_response = tmpl.find("' ' + eos_token") != std::string::npos; + // [variant] add BOS inside history + bool add_bos_inside_history = tmpl.find("bos_token + '[INST]") != std::string::npos; + // [variant] trim spaces from the input message + bool strip_message = tmpl.find("content.strip()") != std::string::npos; + // construct the prompt + bool is_inside_turn = true; // skip BOS at the beginning + ss << "[INST] "; + for (auto message : chat) { + std::string content = strip_message ? trim(message->content) : message->content; + std::string role(message->role); + if (!is_inside_turn) { + is_inside_turn = true; + ss << (add_bos_inside_history ? "<s>[INST] " : "[INST] "); + } + if (role == "system") { + if (support_system_message) { + ss << "<<SYS>>\n" << content << "\n<</SYS>>\n\n"; + } else { + // if the model does not support system message, we still include it in the first message, but without <<SYS>> + ss << content << "\n"; + } + } else if (role == "user") { + ss << content << " [/INST]"; + } else { + ss << (space_around_response ? " " : "") << content << (space_around_response ? " " : "") << "</s>"; + is_inside_turn = false; + } + } + // llama2 templates seem to not care about "add_generation_prompt" + } else if (tmpl.find("<|user|>") != std::string::npos) { + // zephyr template + for (auto message : chat) { + ss << "<|" << message->role << "|>" << "\n" << message->content << "<|endoftext|>\n"; + } + if (add_ass) { + ss << "<|assistant|>\n"; + } + } else { + // template not supported + return -1; + } + dest = ss.str(); + return dest.size(); +} + +LLAMA_API int32_t llama_chat_apply_template( + const struct llama_model * model, + const char * tmpl, + const struct llama_chat_message * chat, + size_t n_msg, + bool add_ass, + char * buf, + int32_t length) { + std::string curr_tmpl(tmpl == nullptr ? "" : tmpl); + if (tmpl == nullptr) { + GGML_ASSERT(model != nullptr); + // load template from model + std::vector<char> model_template(2048, 0); // longest known template is about 1200 bytes + std::string template_key = "tokenizer.chat_template"; + int32_t res = llama_model_meta_val_str(model, template_key.c_str(), model_template.data(), curr_tmpl.size()); + if (res < 0) { + // worst case: there is no information about template, we will use chatml by default + curr_tmpl = "<|im_start|>"; // see llama_chat_apply_template_internal + } else { + curr_tmpl = std::string(model_template.data(), model_template.size()); + } + } + // format the chat to string + std::vector<const llama_chat_message *> chat_vec; + chat_vec.resize(n_msg); + for (size_t i = 0; i < n_msg; i++) { + chat_vec[i] = &chat[i]; + } + std::string formatted_chat; + int32_t res = llama_chat_apply_template_internal(curr_tmpl, chat_vec, formatted_chat, add_ass); + if (res < 0) { + return res; + } + strncpy(buf, formatted_chat.c_str(), length); + return res; +} + struct llama_timings llama_get_timings(struct llama_context * ctx) { struct llama_timings result = { /*.t_start_ms =*/ 1e-3 * ctx->t_start_us, |