Merge remote-tracking branch 'upstream/master' into HEAD

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 9bba563a7796ba7ac0f5191e1c804a9f8998bbf9..fef1b518160abf00e7e6e4ac14a7e656d2ed4046 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -152,7 +152,7 @@ namespace {
 void Search::init() {
 
   for (int i = 1; i < MAX_MOVES; ++i)
-      Reductions[i] = int(21.3 * std::log(i + 0.25 * std::log(i)));
+      Reductions[i] = int(21.9 * std::log(i));
 }
 
 
@@ -312,19 +312,7 @@ void Thread::search() {
   multiPV = std::min(multiPV, rootMoves.size());
   ttHitAverage = TtHitAverageWindow * TtHitAverageResolution / 2;
 
-  int ct = int(Options["Contempt"]) * PawnValueEg / 100; // From centipawns
-
-  // In analysis mode, adjust contempt in accordance with user preference
-  if (Limits.infinite || Options["UCI_AnalyseMode"])
-      ct =  Options["Analysis Contempt"] == "Off"  ? 0
-          : Options["Analysis Contempt"] == "Both" ? ct
-          : Options["Analysis Contempt"] == "White" && us == BLACK ? -ct
-          : Options["Analysis Contempt"] == "Black" && us == WHITE ? -ct
-          : ct;
-
-  // Evaluation score is from the white point of view
-  contempt = (us == WHITE ?  make_score(ct, ct / 2)
-                          : -make_score(ct, ct / 2));
+  trend = SCORE_ZERO;
 
   int searchAgainCounter = 0;
 
@@ -370,11 +358,11 @@ void Thread::search() {
               alpha = std::max(prev - delta,-VALUE_INFINITE);
               beta  = std::min(prev + delta, VALUE_INFINITE);
 
-              // Adjust contempt based on root move's previousScore (dynamic contempt)
-              int dct = ct + (113 - ct / 2) * prev / (abs(prev) + 147);
+              // Adjust trend based on root move's previousScore (dynamic contempt)
+              int tr = 113 * prev / (abs(prev) + 147);
 
-              contempt = (us == WHITE ?  make_score(dct, dct / 2)
-                                      : -make_score(dct, dct / 2));
+              trend = (us == WHITE ?  make_score(tr, tr / 2)
+                                   : -make_score(tr, tr / 2));
           }
 
           // Start with a small aspiration window and, in the case of a fail
@@ -772,6 +760,7 @@ namespace {
             ss->staticEval = eval = -(ss-1)->staticEval;
 
         // Save static evaluation into transposition table
+        if(!excludedMove)
         tte->save(posKey, VALUE_NONE, ss->ttPv, BOUND_NONE, DEPTH_NONE, MOVE_NONE, eval);
     }
 
@@ -792,7 +781,6 @@ namespace {
 
     // Step 7. Futility pruning: child node (~50 Elo)
     if (   !PvNode
-        &&  depth < 9
         &&  eval - futility_margin(depth, improving) >= beta
         &&  eval < VALUE_KNOWN_WIN) // Do not return unproven wins
         return eval;
@@ -1034,8 +1022,7 @@ moves_loop: // When in check, search starts from here
                   continue;
 
               // Futility pruning: parent node (~5 Elo)
-              if (   lmrDepth < 7
-                  && !ss->inCheck
+              if (   !ss->inCheck
                   && ss->staticEval + 174 + 157 * lmrDepth <= alpha
                   &&  (*contHist[0])[movedPiece][to_sq(move)]
                     + (*contHist[1])[movedPiece][to_sq(move)]
@@ -1169,8 +1156,8 @@ moves_loop: // When in check, search starts from here
               r--;
 
           // Increase reduction for cut nodes (~3 Elo)
-          if (cutNode)
-              r += 1 + !captureOrPromotion;
+          if (cutNode && move != ss->killers[0])
+              r += 2;
 
           if (!captureOrPromotion)
           {