From: Joona Kiiski <joona.kiiski@gmail.com>
Date: Tue, 8 Dec 2009 17:19:13 +0000 (+0200)
Subject: Re-enable TT.insert_pv()
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=b056e5d40ab4e90530df53bb110bd74a41a8df07;p=fairystockfish.git

Re-enable TT.insert_pv()

This time make sure that valuable TTentries are not overwritten.

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

diff --git a/src/search.cpp b/src/search.cpp
index 7bacb89..96a945e 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -743,7 +743,7 @@ namespace {
 
         // Write PV to transposition table, in case the relevant entries have
         // been overwritten during the search.
-        //TT.insert_pv(p, ss[0].pv);
+        TT.insert_pv(p, ss[0].pv);
 
         if (AbortSearch)
             break; // Value cannot be trusted. Break out immediately!
diff --git a/src/tt.cpp b/src/tt.cpp
index 55aad11..a8aa1b6 100644
--- a/src/tt.cpp
+++ b/src/tt.cpp
@@ -208,7 +208,9 @@ void TranspositionTable::insert_pv(const Position& pos, Move pv[]) {
 
   for (int i = 0; pv[i] != MOVE_NONE; i++)
   {
-      store(p.get_key(), VALUE_NONE, VALUE_TYPE_NONE, Depth(-127*OnePly), pv[i]);
+      TTEntry *tte = retrieve(p.get_key());
+      if (!tte || tte->move() != pv[i])
+          store(p.get_key(), VALUE_NONE, VALUE_TYPE_NONE, Depth(-127*OnePly), pv[i]);
       p.do_move(pv[i], st);
   }
 }