From: Marco Costalba <mcostalba@gmail.com>
Date: Sat, 7 Nov 2009 18:45:13 +0000 (+0100)
Subject: Revert "IID in pv also when TT move depth is too small"
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=5e112f16daeec7f03a322cbd292bdbabf3246a48

Revert "IID in pv also when TT move depth is too small"

After almost 900 games we are at -2 ELO

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
---

diff --git a/src/search.cpp b/src/search.cpp
index 3cd54b00..15609966 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1103,11 +1103,8 @@ namespace {
     tte = TT.retrieve(pos.get_key());
     ttMove = (tte ? tte->move() : MOVE_NONE);
 
-    // Go with internal iterative deepening if we don't have a TT move or
-    // if search depth is more then 4*OnePly higher then TT move depth.
-    if (   UseIIDAtPVNodes
-        && depth >= 5*OnePly
-        &&(!ttMove || depth > tte->depth() + 4*OnePly))
+    // Go with internal iterative deepening if we don't have a TT move
+    if (UseIIDAtPVNodes && ttMove == MOVE_NONE && depth >= 5*OnePly)
     {
         search_pv(pos, ss, alpha, beta, depth-2*OnePly, ply, threadID);
         ttMove = ss[ply].pv[ply];