Use Color-From-To history stats to help sort moves

[stockfish] / src / movepick.h

diff --git a/src/movepick.h b/src/movepick.h
index b488313a446833db0b5a8a2d1e8a3fa495964252..8028d487f3f5803418f22f12b4b5dbf116cc947f 100644 (file)
--- a/src/movepick.h
+++ b/src/movepick.h
@@ -2,6 +2,7 @@
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
   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
@@ -36,45 +37,55 @@
 /// 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>
+template<typename T, bool CM = false>
 struct Stats {
 
-  static const Value Max = Value(1<<28);
+  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) {
+  void update(Piece pc, Square to, Move m) { table[pc][to] = m; }
 
-    if (m != table[pc][to])
-        table[pc][to] = m;
-  }
-
-  void updateH(Piece pc, Square to, Value v) {
+  void update(Piece pc, Square to, Value v) {
 
-    if (abs(int(v)) >= 324) 
+    if (abs(int(v)) >= 324)
         return;
-    table[pc][to] -= table[pc][to] * abs(int(v)) / 324;
-    table[pc][to] += int(v) * 32;
-  }
 
-  void updateCMH(Piece pc, Square to, Value v) {
-
-    if (abs(int(v)) >= 324) 
-        return;
-    table[pc][to] -= table[pc][to] * abs(int(v)) / 512;
-    table[pc][to] += int(v) * 64;
+    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<Value> HistoryStats;
-typedef Stats<Move> MovesStats;
-typedef Stats<HistoryStats> CounterMovesHistoryStats;
+typedef Stats<Move> MoveStats;
+typedef Stats<Value, false> HistoryStats;
+typedef Stats<Value,  true> CounterMoveStats;
+typedef Stats<CounterMoveStats> CounterMoveHistoryStats;
 
+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
@@ -88,11 +99,11 @@ public:
   MovePicker(const MovePicker&) = delete;
   MovePicker& operator=(const MovePicker&) = delete;
 
-  MovePicker(const Position&, Move, Depth, const HistoryStats&, const CounterMovesHistoryStats&, Square);
-  MovePicker(const Position&, Move, const HistoryStats&, const CounterMovesHistoryStats&, Value);
-  MovePicker(const Position&, Move, Depth, const HistoryStats&, const CounterMovesHistoryStats&, Move, Search::Stack*);
+  MovePicker(const Position&, Move, Value);
+  MovePicker(const Position&, Move, Depth, Square);
+  MovePicker(const Position&, Move, Depth, Search::Stack*);
 
-  template<bool SpNode> Move next_move();
+  Move next_move();
 
 private:
   template<GenType> void score();
@@ -101,9 +112,7 @@ private:
   ExtMove* end() { return endMoves; }
 
   const Position& pos;
-  const HistoryStats& history;
-  const CounterMovesHistoryStats& counterMovesHistory;
-  Search::Stack* ss;
+  const Search::Stack* ss;
   Move countermove;
   Depth depth;
   Move ttMove;
@@ -111,7 +120,7 @@ private:
   Square recaptureSquare;
   Value threshold;
   int stage;
-  ExtMove *endQuiets, *endBadCaptures = moves + MAX_MOVES - 1;
+  ExtMove* endBadCaptures = moves + MAX_MOVES - 1;
   ExtMove moves[MAX_MOVES], *cur = moves, *endMoves = moves;
 };