From: Marco Costalba <mcostalba@gmail.com>
Date: Tue, 10 Dec 2013 06:05:06 +0000 (+0100)
Subject: Sync history and counter moves updating
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=b96079f86be295312859c67a1669283832067674

Sync history and counter moves updating

Change updating rule after a TT hit to match
the same one at the end of the search.

Small change in functionality, but we want to
have uniform rules in the code.

bench: 7767864
---

diff --git a/src/search.cpp b/src/search.cpp
index 5205126a..cf791334 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -573,10 +573,13 @@ namespace {
         if (    ttValue >= beta
             &&  ttMove
             && !pos.capture_or_promotion(ttMove)
-            &&  ttMove != ss->killers[0])
+            && !inCheck)
         {
-            ss->killers[1] = ss->killers[0];
-            ss->killers[0] = ttMove;
+            if (ss->killers[0] != ttMove)
+            {
+                ss->killers[1] = ss->killers[0];
+                ss->killers[0] = ttMove;
+            }
 
             Value bonus = Value(int(depth) * int(depth));
             History.update(pos.moved_piece(ttMove), to_sq(ttMove), bonus);