X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.h;h=0aba61d027c42b63be40581212c55f89ec1b0d94;hp=d0ced0474ffd901e6b34275acf520147001fe506;hb=b508f9561cc2302c129efe8d60f201ff03ee72c8;hpb=8647fbd6ed11c60282e84e4b486a7e8258c88483 diff --git a/src/movepick.h b/src/movepick.h index d0ced047..0aba61d0 100644 --- a/src/movepick.h +++ b/src/movepick.h @@ -1,7 +1,8 @@ /* 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 + Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2015-2018 Marco Costalba, Joona Kiiski, Gary Linscott, 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 @@ -17,49 +18,134 @@ along with this program. If not, see . */ -#if !defined MOVEPICK_H_INCLUDED +#ifndef MOVEPICK_H_INCLUDED #define MOVEPICK_H_INCLUDED -#include "history.h" -#include "move.h" +#include +#include + +#include "movegen.h" #include "position.h" #include "types.h" -struct SearchStack; +/// StatBoards is a generic 2-dimensional array used to store various statistics +template +struct StatBoards : public std::array, Size1> { -/// MovePicker is a class which is used to pick one pseudo 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::get_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. + void fill(const T& v) { + T* p = &(*this)[0][0]; + std::fill(p, p + sizeof(*this) / sizeof(*p), v); + } -class MovePicker { + void update(T& entry, int bonus, const int D) { + + assert(abs(bonus) <= D); // Ensure range is [-32 * D, 32 * D] + assert(abs(32 * D) < (std::numeric_limits::max)()); // Ensure we don't overflow + + entry += bonus * 32 - entry * abs(bonus) / D; + + assert(abs(entry) <= 32 * D); + } +}; + +/// StatCubes is a generic 3-dimensional array used to store various statistics +template +struct StatCubes : public std::array, Size2>, Size1> { + + void fill(const T& v) { + T* p = &(*this)[0][0][0]; + std::fill(p, p + sizeof(*this) / sizeof(*p), v); + } + + void update(T& entry, int bonus, const int D, const int W) { + + assert(abs(bonus) <= D); // Ensure range is [-W * D, W * D] + assert(abs(W * D) < (std::numeric_limits::max)()); // Ensure we don't overflow + + entry += bonus * W - entry * abs(bonus) / D; + + assert(abs(entry) <= W * D); + } +}; + +/// ButterflyBoards are 2 tables (one for each color) indexed by the move's from +/// and to squares, see chessprogramming.wikispaces.com/Butterfly+Boards +typedef StatBoards ButterflyBoards; + +/// PieceToBoards are addressed by a move's [piece][to] information +typedef StatBoards PieceToBoards; - MovePicker& operator=(const MovePicker&); // Silence a warning under MSVC +/// CapturePieceToBoards are addressed by a move's [piece][to][captured piece type] information +typedef StatCubes CapturePieceToBoards; +/// ButterflyHistory records how often quiet moves have been successful or +/// unsuccessful during the current search, and is used for reduction and move +/// ordering decisions. It uses ButterflyBoards as backing store. +struct ButterflyHistory : public ButterflyBoards { + + void update(Color c, Move m, int bonus) { + StatBoards::update((*this)[c][from_to(m)], bonus, 324); + } +}; + +/// PieceToHistory is like ButterflyHistory, but is based on PieceToBoards +struct PieceToHistory : public PieceToBoards { + + void update(Piece pc, Square to, int bonus) { + StatBoards::update((*this)[pc][to], bonus, 936); + } +}; + +/// CapturePieceToHistory is like PieceToHistory, but is based on CapturePieceToBoards +struct CapturePieceToHistory : public CapturePieceToBoards { + + void update(Piece pc, Square to, PieceType captured, int bonus) { + StatCubes::update((*this)[pc][to][captured], bonus, 324, 2); + } +}; + +/// CounterMoveHistory stores counter moves indexed by [piece][to] of the previous +/// move, see chessprogramming.wikispaces.com/Countermove+Heuristic +typedef StatBoards CounterMoveHistory; + +/// ContinuationHistory is the history of a given pair of moves, usually the +/// current one given a previous one. History table is based on PieceToBoards +/// instead of ButterflyBoards. +typedef StatBoards ContinuationHistory; + + +/// 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. + +class MovePicker { public: - MovePicker(const Position&, Move, Depth, const History&, SearchStack*, Value); - MovePicker(const Position&, Move, Depth, const History&); - MovePicker(const Position&, Move, const History&, int parentCapture); - Move get_next_move(); + MovePicker(const MovePicker&) = delete; + MovePicker& operator=(const MovePicker&) = delete; + MovePicker(const Position&, Move, Value, const CapturePieceToHistory*); + MovePicker(const Position&, Move, Depth, const ButterflyHistory*, const CapturePieceToHistory*, Square); + MovePicker(const Position&, Move, Depth, const ButterflyHistory*, const CapturePieceToHistory*, const PieceToHistory**, Move, Move*); + Move next_move(bool skipQuiets = false); private: - void score_captures(); - void score_noncaptures(); - void score_evasions(); - void go_next_phase(); + template void score(); + ExtMove* begin() { return cur; } + ExtMove* end() { return endMoves; } const Position& pos; - const History& H; + const ButterflyHistory* mainHistory; + const CapturePieceToHistory* captureHistory; + const PieceToHistory** contHistory; + Move ttMove, countermove, killers[2]; + ExtMove *cur, *endMoves, *endBadCaptures; + int stage; + Square recaptureSquare; + Value threshold; Depth depth; - Move ttMove; - MoveStack killers[2]; - int captureThreshold, phase; - const uint8_t* phasePtr; - MoveStack *curMove, *lastMove, *lastNonCapture, *badCaptures; - MoveStack moves[MAX_MOVES]; + ExtMove moves[MAX_MOVES]; }; -#endif // !defined(MOVEPICK_H_INCLUDED) +#endif // #ifndef MOVEPICK_H_INCLUDED