X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.h;h=8028d487f3f5803418f22f12b4b5dbf116cc947f;hp=ad76085bd86bbf08fae48ea02044a92a16e85dfb;hb=b3525fa9ea88e230a38d72351826cbc16c282938;hpb=9ba7f701ead00fd4a59841d457d15a15d3b84378

diff --git a/src/movepick.h b/src/movepick.h
index ad76085b..8028d487 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) 2015-2016 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
@@ -17,46 +18,110 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#if !defined MOVEPICK_H_INCLUDED
+#ifndef MOVEPICK_H_INCLUDED
 #define MOVEPICK_H_INCLUDED
 
-#include "depth.h"
-#include "history.h"
+#include <algorithm> // For std::max
+#include <cstring>   // For std::memset
+
+#include "movegen.h"
 #include "position.h"
+#include "search.h"
+#include "types.h"
 
-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
-/// 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.
+/// The Stats struct stores moves statistics. According to the template parameter
+/// the class can store History 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.
+/// Countermoves store the move that refute a previous one. Entries are stored
+/// using only the moving piece and destination square, hence two moves with
+/// different origin but same destination and piece will be considered identical.
+template<typename T, bool CM = false>
+struct Stats {
 
-class MovePicker {
+  static const Value Max = Value(1 << 28);
+
+  const T* operator[](Piece pc) const { return table[pc]; }
+  T* operator[](Piece pc) { return table[pc]; }
+  void clear() { std::memset(table, 0, sizeof(table)); }
+
+  void update(Piece pc, Square to, Move m) { table[pc][to] = m; }
+
+  void update(Piece pc, Square to, Value v) {
+
+    if (abs(int(v)) >= 324)
+        return;
+
+    table[pc][to] -= table[pc][to] * abs(int(v)) / (CM ? 936 : 324);
+    table[pc][to] += int(v) * 32;
+  }
+
+private:
+  T table[PIECE_NB][SQUARE_NB];
+};
+
+typedef Stats<Move> MoveStats;
+typedef Stats<Value, false> HistoryStats;
+typedef Stats<Value,  true> CounterMoveStats;
+typedef Stats<CounterMoveStats> CounterMoveHistoryStats;
 
-  MovePicker& operator=(const MovePicker&); // silence a warning under MSVC
+struct FromToStats {
 
+    Value get(Color c, Move m) const { return table[c][from_sq(m)][to_sq(m)]; }
+    void clear() { std::memset(table, 0, sizeof(table)); }
+
+    void update(Color c, Move m, Value v)
+    {
+        if (abs(int(v)) >= 324)
+            return;
+
+        Square f = from_sq(m);
+        Square t = to_sq(m);
+
+        table[c][f][t] -= table[c][f][t] * abs(int(v)) / 324;
+        table[c][f][t] += int(v) * 32;
+    }
+
+private:
+    Value table[COLOR_NB][SQUARE_NB][SQUARE_NB];
+};
+
+/// 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& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value beta);
-  MovePicker(const Position& p, Move ttm, Depth d, const History& h);
-  Move get_next_move();
+  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*);
+
+  Move next_move();
 
 private:
-  void score_captures();
-  void score_noncaptures();
-  void score_evasions();
-  void go_next_phase();
+  template<GenType> void score();
+  void generate_next_stage();
+  ExtMove* begin() { return moves; }
+  ExtMove* end() { return endMoves; }
 
   const Position& pos;
-  const History& H;
-  Bitboard pinned;
-  MoveStack ttMoves[2], killers[2];
-  int badCaptureThreshold, phase;
-  const uint8_t* phasePtr;
-  MoveStack *curMove, *lastMove, *lastGoodNonCapture, *badCaptures;
-  MoveStack moves[MOVES_MAX];
+  const Search::Stack* ss;
+  Move countermove;
+  Depth depth;
+  Move ttMove;
+  ExtMove killers[3];
+  Square recaptureSquare;
+  Value threshold;
+  int stage;
+  ExtMove* endBadCaptures = moves + MAX_MOVES - 1;
+  ExtMove moves[MAX_MOVES], *cur = moves, *endMoves = moves;
 };
 
-#endif // !defined(MOVEPICK_H_INCLUDED)
+#endif // #ifndef MOVEPICK_H_INCLUDED