X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=a46c44627d4b1677b1f4a0a11f13825d24e0e746;hp=a17a7506856bf82f36d5dbf47f3e55694e6fa22b;hb=6b16ebc82566a69b9336cca6aa7a19ab1824b85d;hpb=f72b7dc99af07c4f012ef229f9d3dcc490d6d69f

diff --git a/src/search.cpp b/src/search.cpp
index a17a7506..a46c4462 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -312,9 +312,14 @@ void MainThread::search() {
       &&  rootMoves[0].pv[0] != MOVE_NONE)
   {
       for (Thread* th : Threads)
-          if (   th->completedDepth > bestThread->completedDepth
-              && th->rootMoves[0].score > bestThread->rootMoves[0].score)
+      {
+          Depth depthDiff = th->completedDepth - bestThread->completedDepth;
+          Value scoreDiff = th->rootMoves[0].score - bestThread->rootMoves[0].score;
+
+          if (   (depthDiff > 0 && scoreDiff >= 0)
+              || (scoreDiff > 0 && depthDiff >= 0))
               bestThread = th;
+      }
   }
 
   previousScore = bestThread->rootMoves[0].score;
@@ -597,7 +602,7 @@ namespace {
     if (!rootNode)
     {
         // Step 2. Check for aborted search and immediate draw
-        if (Signals.stop.load(std::memory_order_relaxed) || pos.is_draw() || ss->ply >= MAX_PLY)
+        if (Signals.stop.load(std::memory_order_relaxed) || pos.is_draw(ss->ply) || ss->ply >= MAX_PLY)
             return ss->ply >= MAX_PLY && !inCheck ? evaluate(pos)
                                                   : DrawValue[pos.side_to_move()];
 
@@ -721,7 +726,7 @@ namespace {
         &&  eval + razor_margin[depth / ONE_PLY] <= alpha)
     {
         if (depth <= ONE_PLY)
-            return qsearch<NonPV, false>(pos, ss, alpha, beta);
+            return qsearch<NonPV, false>(pos, ss, alpha, alpha+1);
 
         Value ralpha = alpha - razor_margin[depth / ONE_PLY];
         Value v = qsearch<NonPV, false>(pos, ss, ralpha, ralpha+1);
@@ -1074,13 +1079,6 @@ moves_loop: // When in check search starts from here
 
           if (value > alpha)
           {
-              // If there is an easy move for this position, clear it if unstable
-              if (    PvNode
-                  &&  thisThread == Threads.main()
-                  &&  EasyMove.get(pos.key())
-                  && (move != EasyMove.get(pos.key()) || moveCount > 1))
-                  EasyMove.clear();
-
               bestMove = move;
 
               if (PvNode && !rootNode) // Update pv even in fail-high case
@@ -1180,7 +1178,7 @@ moves_loop: // When in check search starts from here
     ss->ply = (ss-1)->ply + 1;
 
     // Check for an instant draw or if the maximum ply has been reached
-    if (pos.is_draw() || ss->ply >= MAX_PLY)
+    if (pos.is_draw(ss->ply) || ss->ply >= MAX_PLY)
         return ss->ply >= MAX_PLY && !InCheck ? evaluate(pos)
                                               : DrawValue[pos.side_to_move()];