Do not refresh TT in qsearch

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index cd874ff816156bfcfd036c65de3443a917325341..ec884b3c145afc20dbcdff887e056ba671552827 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -232,7 +232,7 @@ namespace {
   const Value EasyMoveMargin = Value(0x200);
 
   // Last seconds noise filtering (LSN)
-  const bool UseLSNFiltering = false;
+  const bool UseLSNFiltering = true;
   const int LSNTime = 4000; // In milliseconds
   const Value LSNValue = value_from_centipawns(200);
   bool loseOnTime = false;
@@ -387,7 +387,7 @@ bool think(const Position& pos, bool infinite, bool ponder, int side_to_move,
       if (get_option_value_string("Book File") != OpeningBook.file_name())
           OpeningBook.open(get_option_value_string("Book File"));
 
-      Move bookMove = OpeningBook.get_move(pos);
+      Move bookMove = OpeningBook.get_move(pos, get_option_value_bool("Best Book Move"));
       if (bookMove != MOVE_NONE)
       {
           if (PonderSearch)
@@ -560,7 +560,7 @@ void init_search() {
       for (int j = 0; j < 64; j++) // j == moveNumber
       {
           // FIXME: test using log instead of BSR
-          FutilityMarginsMatrix[i][j] = (i < 2 ? 0 : 112 * bitScanReverse32(i * i / 2)) - 8 * j;
+          FutilityMarginsMatrix[i][j] = (i < 2 ? 0 : 112 * bitScanReverse32(i * i / 2)) - 8 * j + 45;
       }
 
   // Init futility move count array
@@ -1301,6 +1301,9 @@ namespace {
 
     if (tte && ok_to_use_TT(tte, depth, beta, ply))
     {
+        // Refresh tte entry to avoid aging
+        TT.store(posKey, tte->value(), tte->type(), tte->depth(), ttMove);
+
         ss[ply].currentMove = ttMove; // Can be MOVE_NONE
         return value_from_tt(tte->value(), ply);
     }
@@ -1379,18 +1382,13 @@ namespace {
             if (nullValue >= value_mate_in(PLY_MAX))
                 nullValue = beta;
 
-            // Do zugzwang verification search for high depths, don't store in TT
-            // if search was stopped.
-            if (   (   depth < 6 * OnePly
-                    || search(pos, ss, beta, depth-5*OnePly, ply, false, threadID) >= beta)
-                && !AbortSearch
-                && !TM.thread_should_stop(threadID))
-            {
-                assert(value_to_tt(nullValue, ply) == nullValue);
+            if (depth < 6 * OnePly)
+                return nullValue;
 
-                TT.store(posKey, nullValue, VALUE_TYPE_NS_LO, depth, MOVE_NONE);
+            // Do zugzwang verification search
+            Value v = search(pos, ss, beta, depth-5*OnePly, ply, false, threadID);
+            if (v >= beta)
                 return nullValue;
-            }
         } else {
             // The null move failed low, which means that we may be faced with
             // some kind of threat. If the previous move was reduced, check if
@@ -1485,7 +1483,7 @@ namespace {
           // Value based pruning
           Depth predictedDepth = newDepth - nonpv_reduction(depth, moveCount); // We illogically ignore reduction condition depth >= 3*OnePly
           futilityValueScaled =  ss[ply].eval + futility_margin(predictedDepth, moveCount)
-                               + H.gain(pos.piece_on(move_from(move)), move_to(move)) + 45;
+                               + H.gain(pos.piece_on(move_from(move)), move_to(move));
 
           if (futilityValueScaled < beta)
           {
@@ -1712,7 +1710,7 @@ namespace {
 
       // Detect blocking evasions that are candidate to be pruned
       evasionPrunable =   isCheck
-                       && bestValue != -VALUE_INFINITE
+                       && bestValue > value_mated_in(PLY_MAX)
                        && !pos.move_is_capture(move)
                        && pos.type_of_piece_on(move_from(move)) != KING
                        && !pos.can_castle(pos.side_to_move());
@@ -1843,7 +1841,7 @@ namespace {
           // Value based pruning
           Depth predictedDepth = newDepth - nonpv_reduction(sp->depth, moveCount);
           futilityValueScaled =  ss[sp->ply].eval + futility_margin(predictedDepth, moveCount)
-                                     + H.gain(pos.piece_on(move_from(move)), move_to(move)) + 45;
+                               + H.gain(pos.piece_on(move_from(move)), move_to(move));
 
           if (futilityValueScaled < sp->beta)
           {
@@ -2769,7 +2767,7 @@ namespace {
         }
 
         // Wait until the thread has finished launching and is gone to sleep
-        while (threads[i].state != THREAD_SLEEPING);
+        while (threads[i].state != THREAD_SLEEPING) {}
     }
   }
 
@@ -2810,7 +2808,7 @@ namespace {
 
     SplitPoint* sp;
 
-    for (sp = threads[threadID].splitPoint; sp && !sp->stopRequest; sp = sp->parent);
+    for (sp = threads[threadID].splitPoint; sp && !sp->stopRequest; sp = sp->parent) {}
     return sp != NULL;
   }