Score and Select Best Thread in same loop (#2125)

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index f021f8ff5eb183517a9391bd6cff6faee74d571c..f1136e3e5b423cfaed45bae25fbc591c341690a7 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -149,7 +149,7 @@ namespace {
 void Search::init() {
 
   for (int i = 1; i < MAX_MOVES; ++i)
-      Reductions[i] = int(1024 * std::log(i) / std::sqrt(1.95));
+     Reductions[i] = int(733.3 * std::log(i));
 }
 
 
@@ -239,21 +239,19 @@ void MainThread::search() {
       for (Thread* th: Threads)
           minScore = std::min(minScore, th->rootMoves[0].score);
 
-      // Vote according to score and depth
+      // Vote according to score and depth, and select the best thread
+      int64_t bestVote = 0;
       for (Thread* th : Threads)
       {
-          int64_t s = th->rootMoves[0].score - minScore + 1;
-          votes[th->rootMoves[0].pv[0]] += 200 + s * s * int(th->completedDepth);
-      }
+          votes[th->rootMoves[0].pv[0]] +=
+               (th->rootMoves[0].score - minScore + 14) * int(th->completedDepth);
 
-      // Select best thread
-      auto bestVote = votes[this->rootMoves[0].pv[0]];
-      for (Thread* th : Threads)
           if (votes[th->rootMoves[0].pv[0]] > bestVote)
           {
               bestVote = votes[th->rootMoves[0].pv[0]];
               bestThread = th;
           }
+      }
   }
 
   previousScore = bestThread->rootMoves[0].score;
@@ -406,17 +404,14 @@ void Thread::search() {
                   beta = (alpha + beta) / 2;
                   alpha = std::max(bestValue - delta, -VALUE_INFINITE);
 
+                  failedHighCnt = 0;
                   if (mainThread)
-                  {
-                      failedHighCnt = 0;
                       mainThread->stopOnPonderhit = false;
-                  }
               }
               else if (bestValue >= beta)
               {
                   beta = std::min(bestValue + delta, VALUE_INFINITE);
-                  if (mainThread)
-                      ++failedHighCnt;
+                  ++failedHighCnt;
               }
               else
                   break;