/*
- Glaurung, a UCI chess playing engine.
- Copyright (C) 2004-2008 Tord Romstad
+ 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
- Glaurung is free software: you can redistribute it and/or modify
+ 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.
-
- Glaurung is distributed in the hope that it will be useful,
+
+ 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 <http://www.gnu.org/licenses/>.
*/
////
#include "depth.h"
-#include "lock.h"
+#include "history.h"
#include "position.h"
//// Types
////
+struct SearchStack;
+
/// MovePicker is a class which is used to pick one legal move at a time from
-/// the current position. It is initialized with a Position object and a few
-/// moves we have reason to believe are good. The most important method is
+/// the current position. It is initialized with a Position object and a few
+/// moves we have reason to believe are good. The most important method is
/// MovePicker::pick_next_move(), which returns a new legal move each time it
/// is called, until there are no legal moves left, when MOVE_NONE is returned.
/// In order to improve the efficiency of the alpha beta algorithm, MovePicker
class MovePicker {
+ MovePicker& operator=(const MovePicker&); // silence a warning under MSVC
+
public:
- MovePicker(Position &p, bool pvnode, Move ttm, Move mk, Move k1, Move k2,
- Depth dpth);
+ MovePicker(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss = NULL, Value beta = -VALUE_INFINITE);
Move get_next_move();
- Move get_next_move(Lock &lock);
- int number_of_moves() const;
- int current_move_score() const;
- Bitboard discovered_check_candidates();
-
- static void init_phase_table();
+ int number_of_evasions() const;
private:
void score_captures();
void score_noncaptures();
- void score_evasions();
- void score_qcaptures();
- Move pick_move_from_list();
-
- Position *pos;
- Move ttMove, mateKiller, killer1, killer2;
- Bitboard pinned, dc;
+ void score_evasions_or_checks();
+ void go_next_phase();
+
+ const Position& pos;
+ const History& H;
+ Bitboard pinned;
+ MoveStack ttMoves[2], killers[2];
+ int badCaptureThreshold, phase;
+ const uint8_t* phasePtr;
+ MoveStack *curMove, *lastMove, *lastGoodNonCapture, *lastBadCapture;
MoveStack moves[256], badCaptures[64];
- bool pvNode;
- Depth depth;
- int phaseIndex;
- int numOfMoves, numOfBadCaptures;
- int movesPicked, badCapturesPicked;
- bool finished;
};
//// Inline functions
////
-/// MovePicker::discovered_check_candidates() returns a bitboard containing
-/// all pieces which can possibly give discovered check. This bitboard is
-/// computed by the constructor function.
+/// MovePicker::number_of_evasions() simply returns the number of moves in
+/// evasions phase. It is intended to be used in positions where the side to
+/// move is in check, for detecting checkmates or situations where there is
+/// only a single reply to check.
+/// WARNING: It works as long as PH_EVASIONS is the _only_ phase for evasions.
-inline Bitboard MovePicker::discovered_check_candidates() {
- return dc;
+inline int MovePicker::number_of_evasions() const {
+ return int(lastMove - moves);
}
#endif // !defined(MOVEPICK_H_INCLUDED)