X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=756b2d5769fb6f44b854cad829f9e1b1242746ef;hp=7876f9314ad93e56242c569e0f79a26e0c7a5498;hb=ae5d2c38e1b9f6a990c29d31a37d6555d197f939;hpb=4f3804f3f39e573a24ece662cbf79fe30368ff1e

diff --git a/src/search.cpp b/src/search.cpp
index 7876f931..756b2d57 100644
--- 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;
@@ -653,9 +656,11 @@ namespace {
                 if (!pos.capture_or_promotion(ttMove))
                     update_quiet_stats(pos, ss, ttMove, nullptr, 0, stat_bonus(depth));
 
-                // Extra penalty for a quiet TT move in previous ply when it gets refuted
-                if ((ss-1)->moveCount == 1 && !pos.captured_piece())
-                    update_continuation_histories(ss-1, pos.piece_on(prevSq), prevSq, -stat_bonus(depth + ONE_PLY));
+                // Extra penalty for a quiet TT or main killer move in previous ply when it gets refuted
+                if (   (ss-1)->moveCount == 1
+                    || ((ss-1)->currentMove == (ss-1)->killers[0] && (ss-1)->killers[0]))
+                    if (!pos.captured_piece())
+                        update_continuation_histories(ss-1, pos.piece_on(prevSq), prevSq, -stat_bonus(depth + ONE_PLY));
             }
             // Penalty for a quiet ttMove that fails low
             else if (!pos.capture_or_promotion(ttMove))
@@ -756,8 +761,9 @@ 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