X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fhistory.h;h=c265777b42a6c4d0bcf60485aae9d80a64625f43;hb=0fcda095df1caa860e8e3f3a714d5545ec9dc122;hp=ddab6cd09f442b57e139d3e2e146c35711c75cc8;hpb=78246035499e277a7099b73bb96ac1e115643d61;p=stockfish
diff --git a/src/history.h b/src/history.h
index ddab6cd0..c265777b 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) 2008-2009 Marco Costalba
+ Copyright (C) 2008-2010 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
@@ -17,22 +17,11 @@
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"
-
-
-////
-//// Types
-////
+#include
+#include "types.h"
/// The History class stores statistics about how often different moves
/// have been successful or unsuccessful during the current search. These
@@ -44,30 +33,38 @@
class History {
public:
- History();
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;
+ Value value(Piece p, Square to) const;
+ void update(Piece p, Square to, Value bonus);
+ Value gain(Piece p, Square to) const;
+ void update_gain(Piece p, Square to, Value gain);
+
+ static const Value MaxValue = Value(1 << 29); // To avoid an overflow
private:
- int history[16][64]; // [piece][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(Value));
+ memset(maxGains, 0, 16 * 64 * sizeof(Value));
+}
-////
-//// Constants and variables
-////
+inline Value 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] + bonus) < 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] = Max(gain, maxGains[p][to] - 1);
+}
#endif // !defined(HISTORY_H_INCLUDED)