X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmovepick.h;h=a7cac4ba85ba64c03ceb29f64a0aa2eca7d5a939;hb=27ba611a3da37423a3502e49beeebe11c9a11d8e;hp=9e81e218247a165269a8d4ed44392352501d0886;hpb=14dbeb22dd04f0954322a58c26833506fb4532a9;p=stockfish
diff --git a/src/movepick.h b/src/movepick.h
index 9e81e218..a7cac4ba 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) 2008-2009 Marco Costalba
+ 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
@@ -17,71 +18,110 @@
along with this program. If not, see .
*/
-
-#if !defined MOVEPICK_H_INCLUDED
+#ifndef MOVEPICK_H_INCLUDED
#define MOVEPICK_H_INCLUDED
-////
-//// Includes
-////
+#include
-#include "depth.h"
-#include "history.h"
+#include "movegen.h"
#include "position.h"
+#include "types.h"
+/// StatBoards is a generic 2-dimensional array used to store various statistics
+template
+struct StatBoards : public std::array, Size1> {
-////
-//// Types
-////
+ void fill(const T& v) {
+ T* p = &(*this)[0][0];
+ std::fill(p, p + sizeof(*this) / sizeof(*p), v);
+ }
+};
-struct SearchStack;
+/// 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;
-/// 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.
+/// PieceToBoards are addressed by a move's [piece][to] information
+typedef StatBoards PieceToBoards;
-class MovePicker {
+/// 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 {
- MovePicker& operator=(const MovePicker&); // silence a warning under MSVC
+ void update(Color c, Move m, int v) {
-public:
- MovePicker(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss = NULL, Value beta = -VALUE_INFINITE);
- Move get_next_move();
- int number_of_evasions() const;
+ const int D = 324;
+ auto& entry = (*this)[c][from_to(m)];
-private:
- void score_captures();
- void score_noncaptures();
- void score_evasions_or_checks();
- void go_next_phase();
+ assert(abs(v) <= D); // Consistency check for below formula
- const Position& pos;
- const History& H;
- MoveStack ttMoves[2], killers[2];
- int badCaptureThreshold, phase;
- const uint8_t* phasePtr;
- MoveStack *curMove, *lastMove, *lastGoodNonCapture, *lastBadCapture;
- Bitboard pinned;
- MoveStack moves[256], badCaptures[64];
+ entry += v * 32 - entry * abs(v) / 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 v) {
+
+ const int D = 936;
+ auto& entry = (*this)[pc][to];
+
+ assert(abs(v) <= D); // Consistency check for below formula
+
+ entry += v * 32 - entry * abs(v) / D;
+
+ assert(abs(entry) <= 32 * D);
+ }
};
+/// CounterMoveStat stores counter moves indexed by [piece][to] of the previous
+/// move, see chessprogramming.wikispaces.com/Countermove+Heuristic
+typedef StatBoards CounterMoveStat;
+
+/// CounterMoveHistoryStat is like CounterMoveStat but instead of a move it
+/// stores a full history (based on PieceTo boards instead of ButterflyBoards).
+typedef StatBoards CounterMoveHistoryStat;
+
+
+/// 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.
+namespace Search { struct Stack; }
+
+class MovePicker {
+public:
+ MovePicker(const MovePicker&) = delete;
+ MovePicker& operator=(const MovePicker&) = delete;
+
+ MovePicker(const Position&, Move, Value);
+ MovePicker(const Position&, Move, Depth, Square);
+ MovePicker(const Position&, Move, Depth, Search::Stack*);
-////
-//// Inline functions
-////
+ Move next_move(bool skipQuiets = false);
-/// 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.
+private:
+ template void score();
+ ExtMove* begin() { return cur; }
+ ExtMove* end() { return endMoves; }
-inline int MovePicker::number_of_evasions() const {
- return int(lastMove - moves);
-}
+ const Position& pos;
+ const Search::Stack* ss;
+ Move killers[2];
+ Move countermove;
+ Depth depth;
+ Move ttMove;
+ Square recaptureSquare;
+ Value threshold;
+ int stage;
+ ExtMove *cur, *endMoves, *endBadCaptures;
+ ExtMove moves[MAX_MOVES];
+};
-#endif // !defined(MOVEPICK_H_INCLUDED)
+#endif // #ifndef MOVEPICK_H_INCLUDED