Less aggressive razoring

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 72bf6e8191db420163a6b32b8aa4f941fd4adcd6..054ef45d5d05858ad1c6e97c624dcc224edb5241 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1003,9 +1003,8 @@ namespace {
       movesSearched[moveCount++] = ss[ply].currentMove = move;
 
       if (moveIsCapture)
-          ss[ply].currentMoveCaptureValue = pos.midgame_value_of_piece_on(move_to(move));
-      else if (move_is_ep(move))
-          ss[ply].currentMoveCaptureValue = PawnValueMidgame;
+          ss[ply].currentMoveCaptureValue =
+          move_is_ep(move)? PawnValueMidgame : pos.midgame_value_of_piece_on(move_to(move));
       else
           ss[ply].currentMoveCaptureValue = Value(0);
 
@@ -1237,13 +1236,12 @@ namespace {
         }
     }
     // Null move search not allowed, try razoring
-    else if (   !isCheck
-             && !value_is_mate(beta)
-             && (  (approximateEval < beta - RazorMargin && depth < RazorDepth)
-                 ||(approximateEval < beta - PawnValueMidgame && depth <= OnePly)))
+    else if (   !value_is_mate(beta)
+             && approximateEval < beta - RazorMargin
+             && depth < RazorDepth)
     {
         Value v = qsearch(pos, ss, beta-1, beta, Depth(0), ply, threadID);
-        if (v < beta)
+        if (v < beta - RazorMargin / 2)
             return v;
     }
 
@@ -1691,8 +1689,11 @@ namespace {
 
       assert(move_is_ok(move));
 
-      ss[sp->ply].currentMoveCaptureValue = move_is_ep(move)?
-        PawnValueMidgame : pos.midgame_value_of_piece_on(move_to(move));
+      if (moveIsCapture)
+          ss[sp->ply].currentMoveCaptureValue =
+          move_is_ep(move)? PawnValueMidgame : pos.midgame_value_of_piece_on(move_to(move));
+      else
+          ss[sp->ply].currentMoveCaptureValue = Value(0);
 
       lock_grab(&(sp->lock));
       int moveCount = ++sp->moves;
@@ -2168,6 +2169,8 @@ namespace {
   Depth extension(const Position &pos, Move m, bool pvNode, bool check,
                   bool singleReply, bool mateThreat, bool* dangerous) {
 
+    assert(m != MOVE_NONE);
+
     Depth result = Depth(0);
     *dangerous = check || singleReply || mateThreat;
 
@@ -2191,10 +2194,12 @@ namespace {
         *dangerous = true;
     }
 
-    if (   pos.midgame_value_of_piece_on(move_to(m)) >= RookValueMidgame
+    if (   pos.move_is_capture(m)
+        && pos.type_of_piece_on(move_to(m)) != PAWN
         && (  pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK)
             - pos.midgame_value_of_piece_on(move_to(m)) == Value(0))
-        && !move_promotion(m))
+        && !move_promotion(m)
+        && !move_is_ep(m))
     {
         result += PawnEndgameExtension[pvNode];
         *dangerous = true;
@@ -2260,7 +2265,7 @@ namespace {
     // value of the threatening piece, don't prune move which defend it.
     if (   !PruneDefendingMoves
         && threat != MOVE_NONE
-        && pos.type_of_piece_on(tto) != NO_PIECE_TYPE
+        && pos.move_is_capture(threat)
         && (   pos.midgame_value_of_piece_on(tfrom) >= pos.midgame_value_of_piece_on(tto)
             || pos.type_of_piece_on(tfrom) == KING)
         && pos.move_attacks_square(m, tto))