X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.h;h=37027ace23153d1dff36b88446df58d5b4be495d;hp=c7b1ddaf58be40533e6e170b8ca6ef1e047b4801;hb=4ede49cd850392f28bc9da9537c111d2c3f0b297;hpb=940c53c366c3993a024efe458fc0fb4fffd3ad70 diff --git a/src/movepick.h b/src/movepick.h index c7b1ddaf..37027ace 100644 --- a/src/movepick.h +++ b/src/movepick.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 Marco Costalba + Copyright (C) 2008-2013 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 @@ -17,103 +17,94 @@ along with this program. If not, see . */ - #if !defined MOVEPICK_H_INCLUDED #define MOVEPICK_H_INCLUDED -//// -//// Includes -//// +#include // For std::max +#include // For std::memset -#include "depth.h" -#include "lock.h" +#include "movegen.h" #include "position.h" +#include "search.h" +#include "types.h" -//// -//// Types -//// +/// The Stats struct stores moves statistics. According to the template parameter +/// the class can store History, Gains and Countermoves. History records how often +/// different moves have been successful or unsuccessful during the current search +/// and is used for reduction and move ordering decisions. Gains records the move's +/// best evaluation gain from one ply to the next and is used for pruning decisions. +/// Countermoves store the move that refute a previous one. Entries are stored +/// according only to moving piece and destination square, hence two moves with +/// different origin but same destination and piece will be considered identical. +template +struct Stats { -/// 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 -/// 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 -/// attempts to return the moves which are most likely to be strongest first. + static const Value Max = Value(2000); -class MovePicker { + const T* operator[](Piece p) const { return table[p]; } + void clear() { std::memset(table, 0, sizeof(table)); } -public: + void update(Piece p, Square to, Move m) { - enum MovegenPhase { - PH_TT_MOVE, // Transposition table move - PH_MATE_KILLER, // Mate killer from the current ply - PH_GOOD_CAPTURES, // Queen promotions and captures with SEE values >= 0 - PH_BAD_CAPTURES, // Queen promotions and captures with SEE values < 0 - PH_KILLER_1, // Killer move 1 from the current ply (not used yet). - PH_KILLER_2, // Killer move 2 from the current ply (not used yet). - PH_NONCAPTURES, // Non-captures and underpromotions - PH_EVASIONS, // Check evasions - PH_QCAPTURES, // Captures in quiescence search - PH_QCHECKS, // Checks in quiescence search - PH_STOP - }; - - MovePicker(const Position& p, bool pvnode, Move ttm, Move mk, Move k1, Move k2, Depth d); - Move get_next_move(); - Move get_next_move(Lock &lock); - int number_of_moves() const; - int current_move_score() const; - MovegenPhase current_move_type() const; - Bitboard discovered_check_candidates() const; - - static void init_phase_table(); + if (m == table[p][to].first) + return; -private: - void score_captures(); - void score_noncaptures(); - void score_evasions(); - void score_qcaptures(); - Move pick_move_from_list(); - int find_best_index(); - int MovePicker::find_best_index(Bitboard* squares, int values[]); + table[p][to].second = table[p][to].first; + table[p][to].first = m; + } - const Position& pos; - Move ttMove, mateKiller, killer1, killer2; - Bitboard pinned, dc; - MoveStack moves[256], badCaptures[64]; - Bitboard capSquares; - int capSqValues[64]; - bool pvNode; - Depth depth; - int phaseIndex; - int numOfMoves, numOfBadCaptures; - int movesPicked, badCapturesPicked; - bool finished; + void update(Piece p, Square to, Value v) { + + if (Gain) + table[p][to] = std::max(v, table[p][to] - 1); + + else if (abs(table[p][to] + v) < Max) + table[p][to] += v; + } + +private: + T table[PIECE_NB][SQUARE_NB]; }; +typedef Stats< true, Value> GainsStats; +typedef Stats HistoryStats; +typedef Stats > CountermovesStats; -//// -//// Inline functions -//// -/// MovePicker::number_of_moves() simply returns the numOfMoves member -/// variable. 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. +/// MovePicker class is used to pick one pseudo legal move at a time from the +/// current position. The most important method is next_move(), which returns a +/// new pseudo legal move each time it is called, until there are no moves left, +/// when MOVE_NONE is returned. In order to improve the efficiency of the alpha +/// beta algorithm, MovePicker attempts to return the moves which are most likely +/// to get a cut-off first. -inline int MovePicker::number_of_moves() const { +class MovePicker { - return numOfMoves; -} + MovePicker& operator=(const MovePicker&); // Silence a warning under MSVC -/// MovePicker::discovered_check_candidates() returns a bitboard containing -/// all pieces which can possibly give discovered check. This bitboard is -/// computed by the constructor function. +public: + MovePicker(const Position&, Move, Depth, const HistoryStats&, Square); + MovePicker(const Position&, Move, const HistoryStats&, PieceType); + MovePicker(const Position&, Move, Depth, const HistoryStats&, Move*, Search::Stack*, Value); -inline Bitboard MovePicker::discovered_check_candidates() const { - return dc; -} + template Move next_move(); + +private: + template void score(); + void generate_next(); + + const Position& pos; + const HistoryStats& history; + Search::Stack* ss; + Move* countermoves; + Depth depth; + Move ttMove; + MoveStack killers[4]; + Square recaptureSquare; + int captureThreshold, phase; + MoveStack *cur, *end, *endQuiets, *endBadCaptures; + MoveStack moves[MAX_MOVES]; +}; #endif // !defined(MOVEPICK_H_INCLUDED)