X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=65ed9b73ffb0886e8e049a329587021c1965e466;hp=4650b1579bf0e11dafd78722151ab5d54f0370d5;hb=6328135264d3b13a2cef3f0c835a27192cae0f40;hpb=3d5b2c8a5104888ec4d1ec44c171e29809e836a6 diff --git a/src/search.cpp b/src/search.cpp index 4650b157..65ed9b73 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -192,7 +192,7 @@ namespace { void Search::init() { for (int i = 1; i < MAX_MOVES; ++i) - Reductions[i] = int((22.0 + 2 * std::log(Threads.size())) * std::log(i)); + Reductions[i] = int((22.0 + 2 * std::log(Threads.size())) * std::log(i + 0.25 * std::log(i))); } @@ -417,7 +417,7 @@ void Thread::search() { // Start with a small aspiration window and, in the case of a fail // high/low, re-search with a bigger window until we don't fail // high/low anymore. - int failedHighCnt = 0; + failedHighCnt = 0; while (true) { Depth adjustedDepth = std::max(1, rootDepth - failedHighCnt - searchAgainCounter); @@ -565,6 +565,7 @@ namespace { constexpr bool PvNode = NT == PV; const bool rootNode = PvNode && ss->ply == 0; + const Depth maxNextDepth = rootNode ? depth : depth + 1; // Check if we have an upcoming move which draws by repetition, or // if the opponent had an alternative move earlier to this position. @@ -829,7 +830,7 @@ namespace { assert(eval - beta >= 0); // Null move dynamic reduction based on depth and value - Depth R = (817 + 71 * depth) / 213 + std::min(int(eval - beta) / 192, 3); + Depth R = (982 + 85 * depth) / 256 + std::min(int(eval - beta) / 192, 3); ss->currentMove = MOVE_NULL; ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0]; @@ -1049,15 +1050,6 @@ moves_loop: // When in check, search starts from here && captureHistory[movedPiece][to_sq(move)][type_of(pos.piece_on(to_sq(move)))] < 0) continue; - // Futility pruning for captures - if ( !givesCheck - && lmrDepth < 6 - && !(PvNode && abs(bestValue) < 2) - && !ss->inCheck - && ss->staticEval + 169 + 244 * lmrDepth - + PieceValue[MG][type_of(pos.piece_on(to_sq(move)))] <= alpha) - continue; - // See based pruning if (!pos.see_ge(move, Value(-221) * depth)) // (~25 Elo) continue; @@ -1186,6 +1178,9 @@ moves_loop: // When in check, search starts from here if (ttCapture) r++; + // Increase reduction at root if failing high + r += rootNode ? thisThread->failedHighCnt * thisThread->failedHighCnt * moveCount / 512 : 0; + // Increase reduction for cut nodes (~10 Elo) if (cutNode) r += 2; @@ -1265,7 +1260,8 @@ moves_loop: // When in check, search starts from here (ss+1)->pv = pv; (ss+1)->pv[0] = MOVE_NONE; - value = -search(pos, ss+1, -beta, -alpha, newDepth, false); + value = -search(pos, ss+1, -beta, -alpha, + std::min(maxNextDepth, newDepth), false); } // Step 18. Undo move