Tweak default values for ucioptions

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 29b7c5f3ebab93a78b832a23905a0e07af535800..a38bbff65a6eef38323da1a611cd56ff70e27ee1 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -38,6 +38,7 @@
 #include "lock.h"
 #include "san.h"
 #include "search.h"
+#include "timeman.h"
 #include "thread.h"
 #include "tt.h"
 #include "ucioption.h"
@@ -198,7 +199,7 @@ namespace {
   Depth PassedPawnExtension[2], PawnEndgameExtension[2], MateThreatExtension[2];
 
   // Minimum depth for use of singular extension
-  const Depth SingularExtensionDepth[2] = { 8 * OnePly /* non-PV */, 6 * OnePly /* PV */};
+  const Depth SingularExtensionDepth[2] = { 7 * OnePly /* non-PV */, 6 * OnePly /* PV */};
 
   // If the TT move is at least SingularExtensionMargin better then the
   // remaining ones we will extend it.
@@ -473,32 +474,7 @@ bool think(const Position& pos, bool infinite, bool ponder, int time[], int incr
   int myIncrement = increment[pos.side_to_move()];
   if (UseTimeManagement)
   {
-      if (!movesToGo) // Sudden death time control
-      {
-          if (myIncrement)
-          {
-              MaxSearchTime = myTime / 30 + myIncrement;
-              AbsoluteMaxSearchTime = Max(myTime / 4, myIncrement - 100);
-          }
-          else // Blitz game without increment
-          {
-              MaxSearchTime = myTime / 30;
-              AbsoluteMaxSearchTime = myTime / 8;
-          }
-      }
-      else // (x moves) / (y minutes)
-      {
-          if (movesToGo == 1)
-          {
-              MaxSearchTime = myTime / 2;
-              AbsoluteMaxSearchTime = (myTime > 3000)? (myTime - 500) : ((myTime * 3) / 4);
-          }
-          else
-          {
-              MaxSearchTime = myTime / Min(movesToGo, 20);
-              AbsoluteMaxSearchTime = Min((4 * myTime) / movesToGo, myTime / 3);
-          }
-      }
+      calc_search_times(myTime, myIncrement, movesToGo, pos.startpos_ply_counter(), MaxSearchTime, AbsoluteMaxSearchTime);
 
       if (get_option_value_bool("Ponder"))
       {
@@ -1062,7 +1038,7 @@ namespace {
         // Refresh tte entry to avoid aging
         TT.store(posKey, tte->value(), tte->type(), tte->depth(), ttMove, tte->static_value(), tte->king_danger());
 
-        ss->currentMove = ttMove; // Can be MOVE_NONE
+        ss->bestMove = ttMove; // Can be MOVE_NONE
         return value_from_tt(tte->value(), ply);
     }
 
@@ -1176,7 +1152,7 @@ namespace {
             if (nullValue == value_mated_in(ply + 2))
                 mateThreat = true;
 
-            threatMove = (ss+1)->currentMove;
+            threatMove = (ss+1)->bestMove;
             if (   depth < ThreatDepth
                 && (ss-1)->reduction
                 && connected_moves(pos, (ss-1)->currentMove, threatMove))
@@ -1213,6 +1189,17 @@ namespace {
                            && is_lower_bound(tte->type())
                            && tte->depth() >= depth - 3 * OnePly;
 
+    // Avoid to do an expensive singular extension search on nodes where
+    // such search had already failed in the past.
+    if (  !PvNode
+        && singularExtensionNode
+        && depth < SingularExtensionDepth[PvNode] + 5 * OnePly)
+    {
+        TTEntry* ttx = TT.retrieve(pos.get_exclusion_key());
+        if (ttx && is_lower_bound(ttx->type()))
+            singularExtensionNode = false;
+    }
+
     // Step 10. Loop through moves
     // Loop through all legal moves until no moves remain or a beta cutoff occurs
     while (   bestValue < beta
@@ -1449,7 +1436,7 @@ namespace {
 
     if (!PvNode && tte && ok_to_use_TT(tte, depth, beta, ply))
     {
-        ss->currentMove = ttMove; // Can be MOVE_NONE
+        ss->bestMove = ttMove; // Can be MOVE_NONE
         return value_from_tt(tte->value(), ply);
     }