X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.h;h=423a6a1805e34a233844024940bd8d66839fb74b;hp=7d6651bb5da07c8c1bd87b9c6b26e7cb86384732;hb=946fa4762539307dcdcb30d08f13d627864e9bcf;hpb=53051eefc741586f72ccbf9a765592c4ca6030bd

diff --git a/src/movepick.h b/src/movepick.h
index 7d6651bb..423a6a18 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) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2015 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
@@ -17,38 +17,57 @@
   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 <algorithm> // For std::max
+
+#include "movegen.h"
 #include "position.h"
 #include "search.h"
 #include "types.h"
 
 
-/// The History class stores statistics about how often different moves
-/// have been successful or unsuccessful during the current search. These
-/// statistics are used for reduction and move ordering decisions. History
-/// entries are stored according only to moving piece and destination square,
-/// in particular two moves with different origin but same destination and
-/// same piece will be considered identical.
+/// 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
+/// using only the moving piece and destination square, hence two moves with
+/// different origin but same destination and piece will be considered identical.
+template<bool Gain, typename T>
+struct Stats {
 
-class History {
-public:
+  static const Value Max = Value(250);
+
+  const T* operator[](Piece pc) const { return table[pc]; }
+  T* operator[](Piece pc) { return table[pc]; }
+
+  void update(Piece pc, Square to, Move m) {
 
-  static const Value Max = Value(2000);
+    if (m != table[pc][to])
+        table[pc][to] = m;
+  }
 
-  const Value* operator[](Piece p) const { return &history[p][0]; }
-  Value gain(Piece p, Square to) const { return gains[p][to]; }
+  void update(Piece pc, Square to, Value v) {
 
-  void clear();
-  void update(Piece p, Square to, Value bonus);
-  void update_gain(Piece p, Square to, Value gain);
+    if (Gain)
+        table[pc][to] = std::max(v, table[pc][to] - 1);
+
+    else if (abs(table[pc][to] + v) < Max)
+        table[pc][to] +=  v;
+  }
 
 private:
-  Value history[PIECE_NB][SQUARE_NB];
-  Value gains[PIECE_NB][SQUARE_NB];
+  T table[PIECE_NB][SQUARE_NB];
 };
 
+typedef Stats< true, Value> GainsStats;
+typedef Stats<false, Value> HistoryStats;
+typedef Stats<false, Move> MovesStats;
+typedef Stats<false, HistoryStats> CounterMovesHistoryStats;
+
 
 /// 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
@@ -58,31 +77,35 @@ private:
 /// to get a cut-off first.
 
 class MovePicker {
+public:
+  MovePicker(const MovePicker&) = delete;
+  MovePicker& operator=(const MovePicker&) = delete;
 
-  MovePicker& operator=(const MovePicker&); // Silence a warning under MSVC
+  MovePicker(const Position&, Move, Depth, const HistoryStats&, const CounterMovesHistoryStats&, Square);
+  MovePicker(const Position&, Move, const HistoryStats&, const CounterMovesHistoryStats&, PieceType);
+  MovePicker(const Position&, Move, Depth, const HistoryStats&, const CounterMovesHistoryStats&, Move, Search::Stack*);
 
-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<bool SpNode> Move next_move();
 
 private:
-  void score_captures();
-  void score_noncaptures();
-  void score_evasions();
-  void generate_next();
+  template<GenType> void score();
+  void generate_next_stage();
+  ExtMove* begin() { return moves; }
+  ExtMove* end() { return endMoves; }
 
   const Position& pos;
-  const History& H;
+  const HistoryStats& history;
+  const CounterMovesHistoryStats& counterMovesHistory;
   Search::Stack* ss;
+  Move countermove;
   Depth depth;
   Move ttMove;
-  MoveStack killers[2];
+  ExtMove killers[3];
   Square recaptureSquare;
-  int captureThreshold, phase;
-  MoveStack *cur, *end, *endQuiets, *endBadCaptures;
-  MoveStack moves[MAX_MOVES];
+  Value captureThreshold;
+  int stage;
+  ExtMove *endQuiets, *endBadCaptures;
+  ExtMove moves[MAX_MOVES], *cur = moves, *endMoves = moves;
 };
 
-#endif // !defined(MOVEPICK_H_INCLUDED)
+#endif // #ifndef MOVEPICK_H_INCLUDED