Just blockSq, not forward file. Bench: 3377831 (#2240)

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index a52cdf0928ab5cdc72800eb4439464979cd57110..9a67a8e429024aa8f5453281c450aacbe322028d 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -605,7 +605,7 @@ namespace {
       return std::min(distance(pos.square<KING>(c), s), 5);
     };
 
-    Bitboard b, bb, squaresToQueen, defendedSquares, unsafeSquares;
+    Bitboard b, bb, squaresToQueen, unsafeSquares;
     Score score = SCORE_ZERO;
 
     b = pe->passed_pawns(Us);
@@ -622,7 +622,7 @@ namespace {
 
         if (r > RANK_3)
         {
-            int w = (r-2) * (r-2) + 2;
+            int w = 5 * r - 13;
             Square blockSq = s + Up;
 
             // Adjust bonus based on the king's proximity
@@ -636,14 +636,11 @@ namespace {
             // If the pawn is free to advance, then increase the bonus
             if (pos.empty(blockSq))
             {
-                defendedSquares = squaresToQueen = forward_file_bb(Us, s);
+                squaresToQueen = forward_file_bb(Us, s);
                 unsafeSquares = passed_pawn_span(Us, s);
 
                 bb = forward_file_bb(Them, s) & pos.pieces(ROOK, QUEEN);
 
-                if (!(pos.pieces(Us) & bb))
-                    defendedSquares &= attackedBy[Us][ALL_PIECES];
-
                 if (!(pos.pieces(Them) & bb))
                     unsafeSquares &= attackedBy[Them][ALL_PIECES] | pos.pieces(Them);
 
@@ -656,7 +653,7 @@ namespace {
                                                              0 ;
 
                 // Assign a larger bonus if the block square is defended
-                if (defendedSquares & blockSq)
+                if ((pos.pieces(Us) & bb) || (attackedBy[Us][ALL_PIECES] & blockSq))
                     k += 5;
 
                 bonus += make_score(k * w, k * w);
@@ -666,7 +663,7 @@ namespace {
         // Scale down bonus for candidate passers which need more than one
         // pawn push to become passed, or have a pawn in front of them.
         if (   !pos.pawn_passed(Us, s + Up)
-            || (pos.pieces(PAWN) & forward_file_bb(Us, s)))
+            || (pos.pieces(PAWN) & (s + Up)))
             bonus = bonus / 2;
 
         score += bonus + PassedFile[file_of(s)];