Do not consider discovered checks in king safety

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 479deb9fe084bcdb0b50184ac1ab43004bf374f2..e44bcdcc64aa942f0bb6206f87dad3543f809631 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -761,12 +761,6 @@ namespace {
         if (b)
             attackUnits += KnightCheckBonus * count_1s_max_15<HasPopCnt>(b);
 
-        // Analyse enemy's discovered checks (only for non-pawns right now,
-        // consider adding pawns later).
-        b = pos.discovered_check_candidates(Them) & ~pos.pieces(PAWN);
-        if (b)
-            attackUnits += DiscoveredCheckBonus * count_1s_max_15<HasPopCnt>(b) * (sente ? 2 : 1);
-
         // To index KingDangerTable[] attackUnits must be in [0, 99] range
         attackUnits = Min(99, Max(0, attackUnits));
 
@@ -799,7 +793,7 @@ namespace {
         assert(pos.pawn_is_passed(Us, s));
 
         int r = int(relative_rank(Us, s) - RANK_2);
-        int tr = Max(0, r * (r - 1));
+        int tr = r * (r - 1);
 
         // Base bonus based on rank
         Value mbonus = Value(20 * tr);