Parameters Tweak

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index d2358ea2e1c2d9ccf1507947d87d9d85192e5e33..749de792dd63c6589b5d8924a7d914991d622fb5 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -72,7 +72,7 @@ namespace {
 
   Depth reduction(bool i, Depth d, int mn, Value delta, Value rootDelta) {
     int r = Reductions[d] * Reductions[mn];
-    return (r + 1449 - int(delta) * 1032 / int(rootDelta)) / 1024 + (!i && r > 941);
+    return (r + 1449 - int(delta) * 1001 / int(rootDelta)) / 1024 + (!i && r > 941);
   }
 
   constexpr int futility_move_count(bool improving, Depth depth) {
@@ -82,7 +82,7 @@ namespace {
 
   // History and stats update bonus, based on depth
   int stat_bonus(Depth d) {
-    return std::min(340 * d - 470, 1855);
+    return std::min(341 * d - 470, 1855);
   }
 
   // Add a small random component to draw evaluations to avoid 3-fold blindness
@@ -290,9 +290,16 @@ void Thread::search() {
 
   bestValue = delta = alpha = -VALUE_INFINITE;
   beta = VALUE_INFINITE;
+  optimism[us] = optimism[~us] = VALUE_ZERO;
 
   if (mainThread)
   {
+
+      int rootComplexity;
+      Eval::evaluate(rootPos, &rootComplexity);
+
+      mainThread->complexity = std::min(1.03 + (rootComplexity - 241) / 1552.0, 1.45);
+
       if (mainThread->bestPreviousScore == VALUE_INFINITE)
           for (int i = 0; i < 4; ++i)
               mainThread->iterValue[i] = VALUE_ZERO;
@@ -311,10 +318,6 @@ void Thread::search() {
 
   multiPV = std::min(multiPV, rootMoves.size());
 
-  complexityAverage.set(153, 1);
-
-  optimism[us] = optimism[~us] = VALUE_ZERO;
-
   int searchAgainCounter = 0;
 
   // Iterative deepening loop until requested to stop or the target depth is reached
@@ -472,10 +475,8 @@ void Thread::search() {
           timeReduction = lastBestMoveDepth + 8 < completedDepth ? 1.57 : 0.65;
           double reduction = (1.4 + mainThread->previousTimeReduction) / (2.08 * timeReduction);
           double bestMoveInstability = 1 + 1.8 * totBestMoveChanges / Threads.size();
-          int complexity = mainThread->complexityAverage.value();
-          double complexPosition = std::min(1.03 + (complexity - 241) / 1552.0, 1.45);
 
-          double totalTime = Time.optimum() * fallingEval * reduction * bestMoveInstability * complexPosition;
+          double totalTime = Time.optimum() * fallingEval * reduction * bestMoveInstability * mainThread->complexity;
 
           // Cap used time in case of a single legal move for a better viewer experience in tournaments
           // yielding correct scores and sufficiently fast moves.
@@ -755,8 +756,6 @@ namespace {
         tte->save(posKey, VALUE_NONE, ss->ttPv, BOUND_NONE, DEPTH_NONE, MOVE_NONE, eval);
     }
 
-    thisThread->complexityAverage.update(complexity);
-
     // Use static evaluation difference to improve quiet move ordering (~4 Elo)
     if (is_ok((ss-1)->currentMove) && !(ss-1)->inCheck && !priorCapture)
     {
@@ -896,11 +895,11 @@ namespace {
         Eval::NNUE::hint_common_parent_position(pos);
     }
 
-    // Step 11. If the position is not in TT, decrease depth by 3.
+    // Step 11. If the position is not in TT, decrease depth by 2 (or by 4 if the TT entry for the current position was hit and the stored depth is greater than or equal to the current depth).
     // Use qsearch if depth is equal or below zero (~9 Elo)
     if (    PvNode
         && !ttMove)
-        depth -= 3;
+        depth -= 2 + 2 * (ss->ttHit &&  tte->depth() >= depth);
 
     if (depth <= 0)
         return qsearch<PV>(pos, ss, alpha, beta);
@@ -1005,7 +1004,6 @@ moves_loop: // When in check, search starts here
           {
               // Futility pruning for captures (~2 Elo)
               if (   !givesCheck
-                  && !PvNode
                   && lmrDepth < 6
                   && !ss->inCheck
                   && ss->staticEval + 182 + 230 * lmrDepth + PieceValue[EG][pos.piece_on(to_sq(move))]
@@ -1058,9 +1056,8 @@ moves_loop: // When in check, search starts here
 
               lmrDepth = std::max(lmrDepth, 0);
 
-              Bitboard occupied;
               // Prune moves with negative SEE (~4 Elo)
-              if (!pos.see_ge(move, occupied, Value(-24 * lmrDepth * lmrDepth - 15 * lmrDepth)))
+              if (!pos.see_ge(move, Value(-24 * lmrDepth * lmrDepth - 16 * lmrDepth)))
                   continue;
           }
       }
@@ -1183,11 +1180,6 @@ moves_loop: // When in check, search starts here
       if (singularQuietLMR)
           r--;
 
-      // Decrease reduction if we move a threatened piece (~1 Elo)
-      if (   depth > 9
-          && (mp.threatenedPieces & from_sq(move)))
-          r--;
-
       // Increase reduction if next ply has a lot of fail high (~5 Elo)
       if ((ss+1)->cutoffCnt > 3)
           r++;
@@ -1201,10 +1193,10 @@ moves_loop: // When in check, search starts here
                      + (*contHist[0])[movedPiece][to_sq(move)]
                      + (*contHist[1])[movedPiece][to_sq(move)]
                      + (*contHist[3])[movedPiece][to_sq(move)]
-                     - 4182;
+                     - 4082;
 
       // Decrease/increase reduction for moves with a good/bad history (~25 Elo)
-      r -= ss->statScore / (11791 + 3992 * (depth > 6 && depth < 19));
+      r -= ss->statScore / (11079 + 4626 * (depth > 6 && depth < 19));
 
       // Step 17. Late moves reduction / extension (LMR, ~117 Elo)
       // We use various heuristics for the sons of a node after the first son has
@@ -1545,7 +1537,6 @@ moves_loop: // When in check, search starts here
                                       prevSq);
 
     int quietCheckEvasions = 0;
-    Bitboard occupied;
 
     // Step 5. Loop through all pseudo-legal moves until no moves remain
     // or a beta cutoff occurs.
@@ -1582,7 +1573,7 @@ moves_loop: // When in check, search starts here
               continue;
           }
 
-          if (futilityBase <= alpha && !pos.see_ge(move, occupied, VALUE_ZERO + 1))
+          if (futilityBase <= alpha && !pos.see_ge(move, VALUE_ZERO + 1))
           {
               bestValue = std::max(bestValue, futilityBase);
               continue;
@@ -1601,7 +1592,7 @@ moves_loop: // When in check, search starts here
           continue;
 
       // Do not search moves with bad enough SEE values (~5 Elo)
-      if (!pos.see_ge(move, occupied, Value(-110)))
+      if (!pos.see_ge(move, Value(-110)))
           continue;
     }