Halve king eval margin

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 8bbd0bff161b3917f6fae299f6f21fe7ff65d2af..207892f4dea1fce081a588dcbab770b8c3aab18e 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -767,7 +767,7 @@ Value do_evaluate(const Position& pos, Value& margin) {
         // be very big, and so capturing a single attacking piece can therefore
         // result in a score change far bigger than the value of the captured piece.
         score -= KingDanger[Us == Search::RootColor][attackUnits];
-        margins[Us] += mg_value(KingDanger[Us == Search::RootColor][attackUnits]);
+        margins[Us] += mg_value(KingDanger[Us == Search::RootColor][attackUnits]) / 2;
     }
 
     if (Trace)
@@ -823,7 +823,7 @@ Value do_evaluate(const Position& pos, Value& margin) {
                 // If there is an enemy rook or queen attacking the pawn from behind,
                 // add all X-ray attacks by the rook or queen. Otherwise consider only
                 // the squares in the pawn's path attacked or occupied by the enemy.
-                if (   (forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN)) // Unlikely
+                if (    unlikely(forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN))
                     && (forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN) & pos.attacks_from<ROOK>(s)))
                     unsafeSquares = squaresToQueen;
                 else