X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fhistory.h;h=c5f72f22afb6fed41da0d5b6ad694fe2d17cabda;hp=ce87b7e137e03ba002636b5c47741a0df01db168;hb=e304db9d1ecf6a2318708483c90fadecf4fac4ee;hpb=d6fdd4f6d95a2a958a73484fb7505460b12af28e diff --git a/src/history.h b/src/history.h index ce87b7e1..c5f72f22 100644 --- a/src/history.h +++ b/src/history.h @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -17,23 +17,13 @@ along with this program. If not, see . */ - #if !defined(HISTORY_H_INCLUDED) #define HISTORY_H_INCLUDED -//// -//// Includes -//// - -#include "depth.h" -#include "move.h" -#include "piece.h" -#include "value.h" +#include +#include - -//// -//// Types -//// +#include "types.h" /// The History class stores statistics about how often different moves /// have been successful or unsuccessful during the current search. These @@ -45,46 +35,38 @@ class History { public: - History(); void clear(); - void success(Piece p, Square to, Depth d); - void failure(Piece p, Square to, Depth d); - int value(Piece p, Square to) const; - void set_gain(Piece p, Square to, Value delta); + Value value(Piece p, Square to) const; + void add(Piece p, Square to, Value bonus); Value gain(Piece p, Square to) const; + void update_gain(Piece p, Square to, Value g); + + static const Value MaxValue = Value(2000); private: - int history[16][64]; // [piece][square] - int maxStaticValueDelta[16][64]; // [piece][from_square][to_square] + Value history[PIECE_NB][SQUARE_NB]; + Value maxGains[PIECE_NB][SQUARE_NB]; }; +inline void History::clear() { + memset(history, 0, 16 * 64 * sizeof(Value)); + memset(maxGains, 0, 16 * 64 * sizeof(Value)); +} -//// -//// Constants and variables -//// - -/// HistoryMax controls how often the history counters will be scaled down: -/// When the history score for a move gets bigger than HistoryMax, all -/// entries in the table are divided by 2. It is difficult to guess what -/// the ideal value of this constant is. Scaling down the scores often has -/// the effect that parts of the search tree which have been searched -/// recently have a bigger importance for move ordering than the moves which -/// have been searched a long time ago. -/// Current policy is to set this as high as possible, but avoid overflow. - -const int HistoryMax = (1 << 28); - - -//// -//// Inline functions -//// - -inline int History::value(Piece p, Square to) const { +inline Value History::value(Piece p, Square to) const { return history[p][to]; } +inline void History::add(Piece p, Square to, Value bonus) { + if (abs(history[p][to] + bonus) < MaxValue) history[p][to] += bonus; +} + inline Value History::gain(Piece p, Square to) const { - return Value(maxStaticValueDelta[p][to]); + return maxGains[p][to]; +} + +inline void History::update_gain(Piece p, Square to, Value g) { + maxGains[p][to] = std::max(g, maxGains[p][to] - 1); } #endif // !defined(HISTORY_H_INCLUDED)