X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fhistory.h;h=47543d54db7ad2995791246a763e843c5bf79464;hp=fdc77ada3b4e4eac9117ef0a77167308b929aee4;hb=877b468e3e8a3b7f7482266007237c6974f7f282;hpb=9fc602bae74b8e09bd45ace3b42a8ce84d56b23c diff --git a/src/history.h b/src/history.h index fdc77ada..47543d54 100644 --- a/src/history.h +++ b/src/history.h @@ -17,13 +17,10 @@ along with this program. If not, see . */ - #if !defined(HISTORY_H_INCLUDED) #define HISTORY_H_INCLUDED -//// -//// Includes -//// +#include #include "depth.h" #include "move.h" @@ -31,10 +28,6 @@ #include "value.h" -//// -//// Types -//// - /// The History class stores statistics about how often different moves /// have been successful or unsuccessful during the current search. These /// statistics are used for reduction and move ordering decisions. History @@ -45,33 +38,39 @@ class History { public: - History(); + History() { clear(); } void clear(); - void success(Piece p, Square to, Depth d); - void failure(Piece p, Square to, Depth d); - int move_ordering_score(Piece p, Square to) const; - void set_gain(Piece p, Square to, Value delta); + int value(Piece p, Square to) const; + void update(Piece p, Square to, Value delta); Value gain(Piece p, Square to) const; + void update_gain(Piece p, Square to, Value delta); + + static const int MaxValue = (1 << 29); // To avoid an overflow private: - int history[16][64]; // [piece][square] - int maxStaticValueDelta[16][64]; // [piece][from_square][to_square] + Value history[16][64]; // [piece][to_square] + Value maxGains[16][64]; // [piece][to_square] }; +inline void History::clear() { + memset(history, 0, 16 * 64 * sizeof(int)); + memset(maxGains, 0, 16 * 64 * sizeof(int)); +} -//// -//// Constants and variables -//// +inline int History::value(Piece p, Square to) const { + return history[p][to]; +} -/// 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. +inline void History::update(Piece p, Square to, Value bonus) { + if (abs(history[p][to]) < MaxValue) history[p][to] += bonus; +} -const int HistoryMax = 50000 * OnePly; +inline Value History::gain(Piece p, Square to) const { + return maxGains[p][to]; +} +inline void History::update_gain(Piece p, Square to, Value gain) { + maxGains[p][to] = (gain >= maxGains[p][to] ? gain : maxGains[p][to] - 1); +} #endif // !defined(HISTORY_H_INCLUDED)