diff --git a/src/search.cpp b/src/search.cpp index 8db295f1..48694cb2 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -1147,7 +1147,14 @@ moves_loop: // When in check, search starts here // Check extensions else if ( givesCheck && depth > 6 - && abs(ss->staticEval) > Value(100)) + && abs(ss->staticEval) > 100) + extension = 1; + + // Quiet ttMove extensions + else if ( PvNode + && move == ttMove + && move == ss->killers[0] + && (*contHist[0])[movedPiece][to_sq(move)] >= 10000) extension = 1; // Add extension to new depth @@ -1223,11 +1230,10 @@ moves_loop: // When in check, search starts here // Decrease/increase reduction for moves with a good/bad history (~30 Elo) r -= ss->statScore / 14721; - // In general we want to cap the LMR depth search at newDepth. But if - // reductions are really negative and movecount is low, we allow this move - // to be searched deeper than the first move in specific cases (note that - // this may lead to hidden double extensions if newDepth got it own extension - // before). + // In general we want to cap the LMR depth search at newDepth. But if reductions + // are really negative and movecount is low, we allow this move to be searched + // deeper than the first move (this may lead to hidden double extensions if + // newDepth got its own extension before). int deeper = r >= -1 ? 0 : noLMRExtension ? 0 : moveCount <= 5 ? 1