X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fsearch.cpp;h=e57131eb7bf0330eba5ab434c24fdbe36344d538;hb=66820a2668a7892a0eb49bedc0ed2c3b4baa74a7;hp=866444a8388e29236d50ec4a609a59f11f45df74;hpb=368f976fb6fc9096d7f19b0443fb4d1af40eec14;p=stockfish

diff --git a/src/search.cpp b/src/search.cpp
index 866444a8..e57131eb 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -70,9 +70,9 @@ namespace {
   // Reductions lookup table, initialized at startup
   int Reductions[MAX_MOVES]; // [depth or moveNumber]
 
-  template <bool PvNode> Depth reduction(bool i, Depth d, int mn) {
+  Depth reduction(bool i, Depth d, int mn) {
     int r = Reductions[d / ONE_PLY] * Reductions[mn] / 1024;
-    return ((r + 512) / 1024 + (!i && r > 1024) - PvNode) * ONE_PLY;
+    return ((r + 512) / 1024 + (!i && r > 1024)) * ONE_PLY;
   }
 
   constexpr int futility_move_count(bool improving, int depth) {
@@ -241,10 +241,8 @@ void MainThread::search() {
 
       // Vote according to score and depth
       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]];
@@ -855,6 +853,7 @@ moves_loop: // When in check, search starts from here
     value = bestValue; // Workaround a bogus 'uninitialized' warning under gcc
     moveCountPruning = false;
     ttCapture = ttMove && pos.capture_or_promotion(ttMove);
+    int singularExtensionLMRmultiplier = 0;
 
     // Step 12. Loop through all pseudo-legal moves until no moves remain
     // or a beta cutoff occurs.
@@ -911,7 +910,12 @@ moves_loop: // When in check, search starts from here
           ss->excludedMove = MOVE_NONE;
 
           if (value < singularBeta)
+              {
               extension = ONE_PLY;
+              singularExtensionLMRmultiplier++;
+              if (value < singularBeta - std::min(3 * depth / ONE_PLY, 39))
+              	  singularExtensionLMRmultiplier++;
+              }
 
           // Multi-cut pruning
           // Our ttMove is assumed to fail high, and now we failed high also on a reduced
@@ -964,7 +968,7 @@ moves_loop: // When in check, search starts from here
                   continue;
 
               // Reduced depth of the next LMR search
-              int lmrDepth = std::max(newDepth - reduction<PvNode>(improving, depth, moveCount), DEPTH_ZERO);
+              int lmrDepth = std::max(newDepth - reduction(improving, depth, moveCount), DEPTH_ZERO);
               lmrDepth /= ONE_PLY;
 
               // Countermoves based pruning (~20 Elo)
@@ -1012,15 +1016,17 @@ moves_loop: // When in check, search starts from here
               || moveCountPruning
               || ss->staticEval + PieceValue[EG][pos.captured_piece()] <= alpha))
       {
-          Depth r = reduction<PvNode>(improving, depth, moveCount);
+          Depth r = reduction(improving, depth, moveCount);
 
           // Decrease reduction if position is or has been on the PV
           if (ttPv)
-              r -= ONE_PLY;
+              r -= 2 * ONE_PLY;
 
           // Decrease reduction if opponent's move count is high (~10 Elo)
           if ((ss-1)->moveCount > 15)
               r -= ONE_PLY;
+          // Decrease reduction if move has been singularly extended
+          r -= singularExtensionLMRmultiplier * ONE_PLY;
 
           if (!captureOrPromotion)
           {