- // Increase reduction if ttMove is a capture (~3 Elo)
- if (ttCapture)
- r++;
-
- // Decrease reduction at PvNodes if bestvalue
- // is vastly different from static evaluation
- if (PvNode && !ss->inCheck && abs(ss->staticEval - bestValue) > 250)
- r--;
-
- // Decrease reduction for PvNodes based on depth
- if (PvNode)
- r -= 1 + 15 / ( 3 + depth );
-
- ss->statScore = thisThread->mainHistory[us][from_to(move)]
- + (*contHist[0])[movedPiece][to_sq(move)]
- + (*contHist[1])[movedPiece][to_sq(move)]
- + (*contHist[3])[movedPiece][to_sq(move)]
- - 4334;
-
- // Decrease/increase reduction for moves with a good/bad history (~30 Elo)
- r -= ss->statScore / 15914;
-
- // 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).
- int deeper = r >= -1 ? 0
- : moveCount <= 4 ? 2
- : PvNode && depth > 4 ? 1
- : cutNode && moveCount <= 8 ? 1
- : 0;
+ value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, d, true);