Simplify Overload condition

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 9d98a63b6cd15afb6badaf708423c9dd5881e471..2fb0e55a9d47b08ed61fa7319aca386200140390 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -337,9 +337,8 @@ namespace {
             else if (bb &= b & ~pos.pieces(Us))
                 score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & bb)];
 
-            // Bonus when behind a pawn
-            if (    relative_rank(Us, s) < RANK_5
-                && (pos.pieces(PAWN) & (s + pawn_push(Us))))
+            // Knight and Bishop bonus for being right behind a pawn
+            if (shift<Down>(pos.pieces(PAWN)) & s)
                 score += MinorBehindPawn;
 
             // Penalty if the piece is far from the king
@@ -561,9 +560,9 @@ namespace {
 
         score += Hanging * popcount(weak & ~attackedBy[Them][ALL_PIECES]);
 
-        // Bonus for overload (non-pawn enemies attacked and defended exactly once)
+        // Bonus for overload (non-pawn enemies attacked once or more and defended exactly once)
         b =  nonPawnEnemies
-           & attackedBy[Us][ALL_PIECES]   & ~attackedBy2[Us]
+           & attackedBy[Us][ALL_PIECES]
            & attackedBy[Them][ALL_PIECES] & ~attackedBy2[Them];
         score += Overload * popcount(b);
     }