Files
llama.cpp/common/reasoning-budget.h
Piotr Wilkin (ilintar) acb7c79069 common/parser: handle reasoning budget (#20297)
* v1

* Finished!

* Handlie cli

* Reasoning sampler

* Apply suggestions from code review

Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>

* Less explosive terminology :)

* Add utf-8 case and tests

* common : migrate reasoning budget sampler to common

* cont : clean up

* cont : expose state and allow passing as initial state

* cont : remove unused imports

* cont : update state machine doc string

---------

Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>
Co-authored-by: Alde Rojas <hello@alde.dev>
2026-03-11 10:26:12 +01:00

42 lines
1.8 KiB
C++

#pragma once
#include "llama.h"
#include <cstdint>
#include <vector>
enum common_reasoning_budget_state {
REASONING_BUDGET_IDLE, // waiting for start sequence
REASONING_BUDGET_COUNTING, // counting down tokens
REASONING_BUDGET_FORCING, // forcing budget message + end sequence
REASONING_BUDGET_WAITING_UTF8, // budget exhausted, waiting for UTF-8 completion
REASONING_BUDGET_DONE, // passthrough forever
};
// Creates a reasoning budget sampler that limits token generation inside a
// reasoning block (e.g. between <think> and </think>).
//
// State machine: IDLE -> COUNTING -> WAITING_UTF8 -> FORCING -> DONE
// IDLE: passthrough, watching for start_tokens sequence
// COUNTING: counting down remaining tokens, watching for natural end_tokens
// WAITING_UTF8: budget exhausted, allowing tokens to complete a UTF-8 sequence
// FORCING: forces forced_tokens token-by-token (all other logits -> -inf)
// DONE: passthrough forever
//
// Parameters:
// vocab - vocabulary (used for UTF-8 boundary detection; can be nullptr)
// start_tokens - token sequence that activates counting
// end_tokens - token sequence for natural deactivation
// forced_tokens - token sequence forced when budget expires
// budget - max tokens allowed in the reasoning block
// initial_state - initial state of the sampler (e.g. IDLE or COUNTING)
// note: COUNTING with budget <= 0 is promoted to FORCING
//
struct llama_sampler * common_reasoning_budget_init(
const struct llama_vocab * vocab,
const std::vector<llama_token> & start_tokens,
const std::vector<llama_token> & end_tokens,
const std::vector<llama_token> & forced_tokens,
int32_t budget,
common_reasoning_budget_state initial_state);