X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fhistory.h;h=7899c842ae99b54fc0b4552639631c317413b4df;hb=0049d3f337b6f3a66a0;hp=f2559499279dc22b0c652ab3198de6736ffcf643;hpb=d3600c39a745179ed6b094b305d0645e83a1ee86;p=stockfish
diff --git a/src/history.h b/src/history.h
index f2559499..7899c842 100644
--- a/src/history.h
+++ b/src/history.h
@@ -1,77 +1,72 @@
/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008 Marco Costalba
+ 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
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
-
+
Stockfish is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
-
+
You should have received a copy of the GNU General Public License
along with this program. If not, see .
*/
-
#if !defined(HISTORY_H_INCLUDED)
#define HISTORY_H_INCLUDED
-////
-//// Includes
-////
+#include
+#include
-#include "depth.h"
-#include "move.h"
-#include "piece.h"
+#include "types.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.
+/// 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
+/// entries are stored according only to moving piece and destination square,
+/// in particular two moves with different origin but same destination and
+/// same piece will be considered identical.
class History {
public:
- History();
void clear();
- void success(Piece p, Move m, Depth d);
- void failure(Piece p, Move m);
- int move_ordering_score(Piece p, Move m) const;
- bool ok_to_prune(Piece p, Move m, Depth d) const;
+ 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 successCount[16][64];
- int failureCount[16][64];
+ 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.
-///
-/// Note that HistoryMax should probably be changed whenever the constant
-/// OnePly in depth.h is changed. This is somewhat annoying. Perhaps it
-/// would be better to scale down the history table at regular intervals?
+inline void History::add(Piece p, Square to, Value bonus) {
+ if (abs(history[p][to] + bonus) < MaxValue) history[p][to] += bonus;
+}
-const int HistoryMax = 50000;
+inline Value History::gain(Piece p, Square to) const {
+ 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)