Simplified select best thread (#958)

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 3387091363212dc40b0d88c17e210cdd44d5db8b..a9fc1c6d4c80b41aec8c20c4b6b2e7c070760050 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -153,11 +153,11 @@ namespace {
     {1, 0, 0, 0, 0, 1, 1 ,1},
   };
 
+  const size_t HalfDensitySize = std::extent<decltype(HalfDensity)>::value;
+
   Value bonus(Depth depth)   { int d = depth / ONE_PLY ; return  Value(d * d + 2 * d - 2); }
   Value penalty(Depth depth) { int d = depth / ONE_PLY ; return -Value(d * d + 4 * d + 1); }
 
-  const size_t HalfDensitySize = std::extent<decltype(HalfDensity)>::value;
-
   EasyMoveManager EasyMove;
   Value DrawValue[COLOR_NB];
 
@@ -312,9 +312,13 @@ 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 (scoreDiff > 0 && depthDiff >= 0)
               bestThread = th;
+      }
   }
 
   previousScore = bestThread->rootMoves[0].score;