X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.h;h=41a83604e09e99b768360ebb66b382d7510918a8;hp=9459b8c2a389e9e2aec27e830ba078931b845df7;hb=ae6a4ebf1f44cb05e96f8f33342ec281b41b0cc0;hpb=834bd9edd79d11566ec3556945a858d2d84a726b diff --git a/src/movepick.h b/src/movepick.h index 9459b8c2..41a83604 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) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2015-2017 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 @@ -17,14 +18,83 @@ along with this program. If not, see . */ -#if !defined MOVEPICK_H_INCLUDED +#ifndef MOVEPICK_H_INCLUDED #define MOVEPICK_H_INCLUDED -#include "history.h" +#include + +#include "movegen.h" #include "position.h" -#include "search.h" #include "types.h" +/// StatBoards is a generic 2-dimensional array used to store various statistics +template +struct StatBoards : public std::array, Size1> { + + void fill(const T& v) { + T* p = &(*this)[0][0]; + std::fill(p, p + sizeof(*this) / sizeof(*p), v); + } +}; + +/// 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; + +/// 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) { + + const int D = 324; + auto& entry = (*this)[c][from_to(m)]; + + assert(abs(bonus) <= D); // Consistency check for below formula + assert([&]{ + int v = entry + bonus * 32 - entry * abs(bonus) / D; + return INT16_MIN < v && v < INT16_MAX; + }()); + + entry += bonus * 32 - entry * abs(bonus) / D; + + assert(abs(entry) <= 32 * D); + } +}; + +/// PieceToHistory is like ButterflyHistory, but is based on PieceToBoards +struct PieceToHistory : public PieceToBoards { + + void update(Piece pc, Square to, int bonus) { + + const int D = 936; + auto& entry = (*this)[pc][to]; + + assert(abs(bonus) <= D); // Consistency check for below formula + assert([&]{ + int v = entry + bonus * 32 - entry * abs(bonus) / D; + return INT16_MIN < v && v < INT16_MAX; + }()); + + entry += bonus * 32 - entry * abs(bonus) / D; + + assert(abs(entry) <= 32 * D); + } +}; + +/// 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 @@ -34,31 +104,29 @@ /// to get a cut-off first. class MovePicker { - - MovePicker& operator=(const MovePicker&); // Silence a warning under MSVC - public: - MovePicker(const Position&, Move, Depth, const History&, Search::Stack*, Value); - MovePicker(const Position&, Move, Depth, const History&, Square); - MovePicker(const Position&, Move, const History&, PieceType); - template Move next_move(); + MovePicker(const MovePicker&) = delete; + MovePicker& operator=(const MovePicker&) = delete; + MovePicker(const Position&, Move, Value); + MovePicker(const Position&, Move, Depth, const ButterflyHistory*, const PieceToHistory**, Square); + MovePicker(const Position&, Move, Depth, const ButterflyHistory*, const PieceToHistory**, Move, Move*); + Move next_move(bool skipQuiets = false); private: - void score_captures(); - void score_noncaptures(); - void score_evasions(); - void generate_next(); + template void score(); + ExtMove* begin() { return cur; } + ExtMove* end() { return endMoves; } const Position& pos; - const History& H; - Search::Stack* ss; - Depth depth; - Move ttMove; - MoveStack killers[2]; + const ButterflyHistory* mainHistory; + const PieceToHistory** contHistory; + Move ttMove, countermove, killers[2]; + ExtMove *cur, *endMoves, *endBadCaptures; + int stage; Square recaptureSquare; - int captureThreshold, phase; - MoveStack *cur, *end, *endQuiets, *endBadCaptures; - MoveStack moves[MAX_MOVES]; + Value threshold; + Depth depth; + ExtMove moves[MAX_MOVES]; }; -#endif // !defined(MOVEPICK_H_INCLUDED) +#endif // #ifndef MOVEPICK_H_INCLUDED