New voting formula for threads

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index c48865c637210aa7c41defa21877d936884889ae..02f40199938810008ac2618bdd94e0ed15353861 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -254,7 +254,7 @@ void MainThread::search() {
       && !Skill(Options["Skill Level"]).enabled()
       &&  rootMoves[0].pv[0] != MOVE_NONE)
   {
-      std::map<Move, int> votes;
+      std::map<Move, int64_t> votes;
       Value minScore = this->rootMoves[0].score;
 
       // Find out minimum score and reset votes for moves which can be voted
@@ -265,12 +265,13 @@ void MainThread::search() {
       }
 
       // Vote according to score and depth
+      auto square = [](int64_t x) { return x * x; };
       for (Thread* th : Threads)
-          votes[th->rootMoves[0].pv[0]] +=  int(th->rootMoves[0].score - minScore)
-                                          + int(th->completedDepth);
+          votes[th->rootMoves[0].pv[0]] += 200 + (square(th->rootMoves[0].score - minScore + 1)
+                                                  * int64_t(th->completedDepth));
 
       // Select best thread
-      int bestVote = votes[this->rootMoves[0].pv[0]];
+      int64_t bestVote = votes[this->rootMoves[0].pv[0]];
       for (Thread* th : Threads)
       {
           if (votes[th->rootMoves[0].pv[0]] > bestVote)
@@ -303,6 +304,7 @@ void MainThread::search() {
 void Thread::search() {
 
   Stack stack[MAX_PLY+7], *ss = stack+4; // To reference from (ss-4) to (ss+2)
+  Move  pv[MAX_PLY+1];
   Value bestValue, alpha, beta, delta;
   Move  lastBestMove = MOVE_NONE;
   Depth lastBestMoveDepth = DEPTH_ZERO;
@@ -314,6 +316,7 @@ void Thread::search() {
   std::memset(ss-4, 0, 7 * sizeof(Stack));
   for (int i = 4; i > 0; i--)
      (ss-i)->continuationHistory = &this->continuationHistory[NO_PIECE][0]; // Use as sentinel
+  ss->pv = pv;
 
   bestValue = delta = alpha = -VALUE_INFINITE;
   beta = VALUE_INFINITE;
@@ -756,8 +759,9 @@ namespace {
     }
 
     // Step 7. Razoring (~2 Elo)
-    if (   depth < 2 * ONE_PLY
-        && eval <= alpha - RazorMargin)
+    if (   !rootNode // The required rootNode PV handling is not available in qsearch
+        &&  depth < 2 * ONE_PLY
+        &&  eval <= alpha - RazorMargin)
         return qsearch<NT>(pos, ss, alpha, beta);
 
     improving =   ss->staticEval >= (ss-2)->staticEval
@@ -960,7 +964,7 @@ moves_loop: // When in check, search starts from here
       {
           if (   !captureOrPromotion
               && !givesCheck
-              && (!pos.advanced_pawn_push(move) || pos.non_pawn_material() >= Value(5000)))
+              && !pos.advanced_pawn_push(move))
           {
               // Move count based pruning (~30 Elo)
               if (moveCountPruning)