Reformat previous patch

No functional change.

src/movepick.cpp

@@ -70,8 +70,8 @@ namespace {
 /// search captures, promotions and some checks) and about how important good
 /// move ordering is at the current node.
 
-MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h,
+MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h, const Refutations& r,
-                       Search::Stack* s, Move refutationMove, Value beta) : pos(p), Hist(h), depth(d) {
+                       Search::Stack* s, Value beta) : pos(p), Hist(h), depth(d) {
 
   assert(d > DEPTH_ZERO);
 
@@ -89,7 +89,8 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h,
 
       killers[0].move = ss->killers[0];
       killers[1].move = ss->killers[1];
-      killers[2].move = refutationMove;
+      Square prevSq = to_sq((ss-1)->currentMove);
+      killers[2].move = r[pos.piece_on(prevSq)][prevSq];
 
       // Consider sligtly negative captures as good if at low depth and far from beta
       if (ss && ss->staticEval < beta - PawnValueMg && d < 3 * ONE_PLY)

src/movepick.h

@@ -30,21 +30,23 @@
 
 
 /// The Stats struct stores moves statistics. According to the template parameter
-/// the class can store both History and Gains type statistics. History records
+/// the class can store History, Gains and Refutations statistics. 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. Entries are stored according only to moving piece and
+/// for pruning decisions. Refutations store the move that refute a previous one.
-/// destination square, in particular two moves with different origin but same
+/// Entries are stored according only to moving piece and destination square, in
-/// destination and same piece will be considered identical.
+/// particular two moves with different origin but same destination and same piece
-template<bool Gain>
+/// will be considered identical.
+template<bool Gain, typename T>
 struct Stats {
 
   static const Value Max = Value(2000);
 
-  const Value* operator[](Piece p) const { return &table[p][0]; }
+  const T* operator[](Piece p) const { return &table[p][0]; }
   void clear() { memset(table, 0, sizeof(table)); }
 
+  void update(Piece p, Square to, Move m) { table[p][to] = m; }
   void update(Piece p, Square to, Value v) {
 
     if (Gain)
@@ -55,23 +57,13 @@ struct Stats {
   }
 
 private:
-  Value table[PIECE_NB][SQUARE_NB];
+  T table[PIECE_NB][SQUARE_NB];
 };
 
-typedef Stats<false> History;
+typedef Stats<true, Value> Gains;
-typedef Stats<true> Gains;
+typedef Stats<false, Value> History;
+typedef Stats<false, Move> Refutations;
 
-// FIXME: Document me
-struct RefutationTable {
-
-  void clear() { memset(table, 0, sizeof(table)); }
-  void update(Piece p, Square to, Move m) { table[p][to] = m; }
-  Move get(Piece p, Square to) const { return table[p][to]; }
-
-private:
-  Move table[PIECE_NB][SQUARE_NB]; // Mapping: "move A" -> "move B which refutes move A"
-
-};
 
 /// 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
@@ -85,7 +77,7 @@ class MovePicker {
   MovePicker& operator=(const MovePicker&); // Silence a warning under MSVC
 
 public:
-  MovePicker(const Position&, Move, Depth, const History&, Search::Stack*, Move, Value);
+  MovePicker(const Position&, Move, Depth, const History&, const Refutations&, Search::Stack*, Value);
   MovePicker(const Position&, Move, Depth, const History&, Square);
   MovePicker(const Position&, Move, const History&, PieceType);
   template<bool SpNode> Move next_move();

src/search.cpp

@@ -88,7 +88,7 @@ namespace {
   Value DrawValue[COLOR_NB];
   History Hist;
   Gains Gain;
-  RefutationTable Refutation;
+  Refutations Refutation;
 
   template <NodeType NT>
   Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth);
@@ -766,12 +766,7 @@ namespace {
 
 split_point_start: // At split points actual search starts from here
 
-    Move prevMove = (ss-1)->currentMove;
+    MovePicker mp(pos, ttMove, depth, Hist, Refutation, ss, PvNode ? -VALUE_INFINITE : beta);
-    Square prevSq = to_sq(prevMove);
-    Piece  prevP  = pos.piece_on(prevSq);
-    Move refutationMove = Refutation.get(prevP, prevSq); 
-
-    MovePicker mp(pos, ttMove, depth, Hist, ss, refutationMove, PvNode ? -VALUE_INFINITE : beta);
     CheckInfo ci(pos);
     value = bestValue; // Workaround a bogus 'uninitialized' warning under gcc
     singularExtensionNode =   !RootNode
@@ -1097,7 +1092,8 @@ split_point_start: // At split points actual search starts from here
             // Increase history value of the cut-off move
             Value bonus = Value(int(depth) * int(depth));
             Hist.update(pos.piece_moved(bestMove), to_sq(bestMove), bonus);
-            Refutation.update(prevP, prevSq, bestMove);
+            Square prevSq = to_sq((ss-1)->currentMove);
+            Refutation.update(pos.piece_on(prevSq), prevSq, bestMove);
 
             // Decrease history of all the other played non-capture moves
             for (int i = 0; i < playedMoveCount - 1; i++)