Prioritize checks in movepicker

[stockfish] / src / movepick.cpp

diff --git a/src/movepick.cpp b/src/movepick.cpp
index b0166c6e962b55a169f75ce6f6abbee65b4e029b..636f4ba7987a90113c409bf0df35961a88574769 100644 (file)
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -106,7 +106,7 @@ void MovePicker::score() {
 
   static_assert(Type == CAPTURES || Type == QUIETS || Type == EVASIONS, "Wrong type");
 
-  Bitboard threatened, threatenedByPawn, threatenedByMinor, threatenedByRook;
+  [[maybe_unused]] Bitboard threatened, threatenedByPawn, threatenedByMinor, threatenedByRook;
   if constexpr (Type == QUIETS)
   {
       Color us = pos.side_to_move();
@@ -122,14 +122,6 @@ void MovePicker::score() {
                   | (pos.pieces(us, ROOK)  & threatenedByMinor)
                   | (pos.pieces(us, KNIGHT, BISHOP) & threatenedByPawn);
   }
-  else
-  {
-      // Silence unused variable warnings
-      (void) threatened;
-      (void) threatenedByPawn;
-      (void) threatenedByMinor;
-      (void) threatenedByRook;
-  }
 
   for (auto& m : *this)
       if constexpr (Type == CAPTURES)
@@ -137,7 +129,7 @@ void MovePicker::score() {
                    +     (*captureHistory)[pos.moved_piece(m)][to_sq(m)][type_of(pos.piece_on(to_sq(m)))];
 
       else if constexpr (Type == QUIETS)
-          m.value =      (*mainHistory)[pos.side_to_move()][from_to(m)]
+          m.value =  2 * (*mainHistory)[pos.side_to_move()][from_to(m)]
                    + 2 * (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)]
                    +     (*continuationHistory[1])[pos.moved_piece(m)][to_sq(m)]
                    +     (*continuationHistory[3])[pos.moved_piece(m)][to_sq(m)]
@@ -147,15 +139,15 @@ void MovePicker::score() {
                           : type_of(pos.moved_piece(m)) == ROOK  && !(to_sq(m) & threatenedByMinor) ? 25000
                           :                                         !(to_sq(m) & threatenedByPawn)  ? 15000
                           :                                                                           0)
-                          :                                                                           0);
-
+                          :                                                                           0)
+                   +     bool(pos.check_squares(type_of(pos.moved_piece(m))) & to_sq(m)) * 16384;
       else // Type == EVASIONS
       {
           if (pos.capture(m))
               m.value =  PieceValue[MG][pos.piece_on(to_sq(m))]
                        - Value(type_of(pos.moved_piece(m)));
           else
-              m.value =      (*mainHistory)[pos.side_to_move()][from_to(m)]
+              m.value =  2 * (*mainHistory)[pos.side_to_move()][from_to(m)]
                        + 2 * (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)]
                        - (1 << 28);
       }