X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fsearch.cpp;h=a41ea4fd269ed6b5ad97159f30ac8e82a7ef16c0;hb=472e726bff0d0e496dc8359cc071726a76317a72;hp=5cb9750c3235a72d6c33fc99943c379c85ac4380;hpb=29b5ad5deaf323f43019443b322090caec13f847;p=stockfish diff --git a/src/search.cpp b/src/search.cpp index 5cb9750c..a41ea4fd 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -63,7 +63,7 @@ namespace { // Futility margin Value futility_margin(Depth d, bool improving) { - return Value(158 * (d - improving)); + return Value(154 * (d - improving)); } // Reductions lookup table, initialized at startup @@ -71,7 +71,7 @@ namespace { Depth reduction(bool i, Depth d, int mn, Value delta, Value rootDelta) { int r = Reductions[d] * Reductions[mn]; - return (r + 1460 - int(delta) * 1024 / int(rootDelta)) / 1024 + (!i && r > 937); + return (r + 1449 - int(delta) * 1032 / int(rootDelta)) / 1024 + (!i && r > 941); } constexpr int futility_move_count(bool improving, Depth depth) { @@ -81,7 +81,7 @@ namespace { // History and stats update bonus, based on depth int stat_bonus(Depth d) { - return std::min(350 * d - 400, 1650); + return std::min(340 * d - 470, 1855); } // Add a small random component to draw evaluations to avoid 3-fold blindness @@ -161,7 +161,7 @@ namespace { void Search::init() { for (int i = 1; i < MAX_MOVES; ++i) - Reductions[i] = int((20.26 + std::log(Threads.size()) / 2) * std::log(i)); + Reductions[i] = int((19.47 + std::log(Threads.size()) / 2) * std::log(i)); } @@ -354,12 +354,12 @@ void Thread::search() { if (rootDepth >= 4) { Value prev = rootMoves[pvIdx].averageScore; - delta = Value(10) + int(prev) * prev / 15400; + delta = Value(10) + int(prev) * prev / 16502; alpha = std::max(prev - delta,-VALUE_INFINITE); beta = std::min(prev + delta, VALUE_INFINITE); // Adjust optimism based on root move's previousScore - int opt = 116 * prev / (std::abs(prev) + 170); + int opt = 120 * prev / (std::abs(prev) + 161); optimism[ us] = Value(opt); optimism[~us] = -optimism[us]; } @@ -462,16 +462,16 @@ void Thread::search() { && !Threads.stop && !mainThread->stopOnPonderhit) { - double fallingEval = (71 + 12 * (mainThread->bestPreviousAverageScore - bestValue) - + 6 * (mainThread->iterValue[iterIdx] - bestValue)) / 656.7; + double fallingEval = (69 + 13 * (mainThread->bestPreviousAverageScore - bestValue) + + 6 * (mainThread->iterValue[iterIdx] - bestValue)) / 619.6; fallingEval = std::clamp(fallingEval, 0.5, 1.5); // If the bestMove is stable over several iterations, reduce time accordingly - timeReduction = lastBestMoveDepth + 9 < completedDepth ? 1.37 : 0.65; - double reduction = (1.4 + mainThread->previousTimeReduction) / (2.15 * timeReduction); - double bestMoveInstability = 1 + 1.7 * totBestMoveChanges / Threads.size(); + 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(1.0 + (complexity - 261) / 1738.7, 1.5); + double complexPosition = std::min(1.03 + (complexity - 241) / 1552.0, 1.45); double totalTime = Time.optimum() * fallingEval * reduction * bestMoveInstability * complexPosition; @@ -491,7 +491,7 @@ void Thread::search() { Threads.stop = true; } else if ( !mainThread->ponder - && Time.elapsed() > totalTime * 0.53) + && Time.elapsed() > totalTime * 0.50) Threads.increaseDepth = false; else Threads.increaseDepth = true; @@ -760,7 +760,7 @@ namespace { // Use static evaluation difference to improve quiet move ordering (~4 Elo) if (is_ok((ss-1)->currentMove) && !(ss-1)->inCheck && !priorCapture) { - int bonus = std::clamp(-19 * int((ss-1)->staticEval + ss->staticEval), -1940, 1940); + int bonus = std::clamp(-19 * int((ss-1)->staticEval + ss->staticEval), -1920, 1920); thisThread->mainHistory[~us][from_to((ss-1)->currentMove)] << bonus; } @@ -770,13 +770,13 @@ namespace { // margin and the improving flag are used in various pruning heuristics. improvement = (ss-2)->staticEval != VALUE_NONE ? ss->staticEval - (ss-2)->staticEval : (ss-4)->staticEval != VALUE_NONE ? ss->staticEval - (ss-4)->staticEval - : 172; + : 156; improving = improvement > 0; // Step 7. Razoring (~1 Elo). // If eval is really low check with qsearch if it can exceed alpha, if it can't, // return a fail low. - if (eval < alpha - 394 - 255 * depth * depth) + if (eval < alpha - 426 - 252 * depth * depth) { value = qsearch(pos, ss, alpha - 1, alpha); if (value < alpha) @@ -786,19 +786,19 @@ namespace { // Step 8. Futility pruning: child node (~40 Elo). // The depth condition is important for mate finding. if ( !ss->ttPv - && depth < 8 - && eval - futility_margin(depth, improving) - (ss-1)->statScore / 304 >= beta + && depth < 9 + && eval - futility_margin(depth, improving) - (ss-1)->statScore / 280 >= beta && eval >= beta - && eval < 28580) // larger than VALUE_KNOWN_WIN, but smaller than TB wins + && eval < 25128) // larger than VALUE_KNOWN_WIN, but smaller than TB wins return eval; // Step 9. Null move search with verification search (~35 Elo) if ( !PvNode && (ss-1)->currentMove != MOVE_NULL - && (ss-1)->statScore < 18200 + && (ss-1)->statScore < 18755 && eval >= beta && eval >= ss->staticEval - && ss->staticEval >= beta - 20 * depth - improvement / 14 + 235 + complexity / 24 + && ss->staticEval >= beta - 19 * depth - improvement / 13 + 253 + complexity / 25 && !excludedMove && pos.non_pawn_material(us) && (ss->ply >= thisThread->nmpMinPly || us != thisThread->nmpColor)) @@ -806,7 +806,7 @@ namespace { assert(eval - beta >= 0); // Null move dynamic reduction based on depth, eval and complexity of position - Depth R = std::min(int(eval - beta) / 165, 6) + depth / 3 + 4 - (complexity > 800); + Depth R = std::min(int(eval - beta) / 168, 6) + depth / 3 + 4 - (complexity > 825); ss->currentMove = MOVE_NULL; ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0]; @@ -842,7 +842,7 @@ namespace { } } - probCutBeta = beta + 180 - 54 * improving; + probCutBeta = beta + 186 - 54 * improving; // Step 10. ProbCut (~10 Elo) // If we have a good enough capture and a reduced search returns a value @@ -904,14 +904,14 @@ namespace { return qsearch(pos, ss, alpha, beta); if ( cutNode - && depth >= 9 + && depth >= 7 && !ttMove) depth -= 2; moves_loop: // When in check, search starts here // Step 12. A small Probcut idea, when we are in check (~4 Elo) - probCutBeta = beta + 402; + probCutBeta = beta + 391; if ( ss->inCheck && !PvNode && depth >= 2 @@ -1006,14 +1006,14 @@ moves_loop: // When in check, search starts here // Futility pruning for captures (~2 Elo) if ( !givesCheck && !PvNode - && lmrDepth < 7 + && lmrDepth < 6 && !ss->inCheck - && ss->staticEval + 185 + 203 * lmrDepth + PieceValue[EG][pos.piece_on(to_sq(move))] - + captureHistory[movedPiece][to_sq(move)][type_of(pos.piece_on(to_sq(move)))] / 6 < alpha) + && ss->staticEval + 182 + 230 * lmrDepth + PieceValue[EG][pos.piece_on(to_sq(move))] + + captureHistory[movedPiece][to_sq(move)][type_of(pos.piece_on(to_sq(move)))] / 7 < alpha) continue; // SEE based pruning (~11 Elo) - if (!pos.see_ge(move, Value(-220) * depth)) + if (!pos.see_ge(move, Value(-206) * depth)) continue; } else @@ -1024,24 +1024,24 @@ moves_loop: // When in check, search starts here // Continuation history based pruning (~2 Elo) if ( lmrDepth < 5 - && history < -4180 * (depth - 1)) + && history < -4405 * (depth - 1)) continue; history += 2 * thisThread->mainHistory[us][from_to(move)]; - lmrDepth += history / 7208; + lmrDepth += history / 7278; lmrDepth = std::max(lmrDepth, -2); // Futility pruning: parent node (~13 Elo) if ( !ss->inCheck && lmrDepth < 13 - && ss->staticEval + 103 + 136 * lmrDepth <= alpha) + && ss->staticEval + 103 + 138 * lmrDepth <= alpha) continue; lmrDepth = std::max(lmrDepth, 0); // Prune moves with negative SEE (~4 Elo) - if (!pos.see_ge(move, Value(-25 * lmrDepth * lmrDepth - 16 * lmrDepth))) + if (!pos.see_ge(move, Value(-24 * lmrDepth * lmrDepth - 15 * lmrDepth))) continue; } } @@ -1056,7 +1056,7 @@ moves_loop: // When in check, search starts here // a reduced search on all the other moves but the ttMove and if the // result is lower than ttValue minus a margin, then we will extend the ttMove. if ( !rootNode - && depth >= 4 - (thisThread->completedDepth > 22) + 2 * (PvNode && tte->is_pv()) + && depth >= 4 - (thisThread->completedDepth > 21) + 2 * (PvNode && tte->is_pv()) && move == ttMove && !excludedMove // Avoid recursive singular search /* && ttValue != VALUE_NONE Already implicit in the next condition */ @@ -1064,7 +1064,7 @@ moves_loop: // When in check, search starts here && (tte->bound() & BOUND_LOWER) && tte->depth() >= depth - 3) { - Value singularBeta = ttValue - (3 + (ss->ttPv && !PvNode)) * depth; + Value singularBeta = ttValue - (2 + (ss->ttPv && !PvNode)) * depth; Depth singularDepth = (depth - 1) / 2; ss->excludedMove = move; @@ -1083,7 +1083,7 @@ moves_loop: // When in check, search starts here && ss->doubleExtensions <= 10) { extension = 2; - depth += depth < 12; + depth += depth < 13; } } @@ -1106,15 +1106,15 @@ moves_loop: // When in check, search starts here // Check extensions (~1 Elo) else if ( givesCheck - && depth > 9 - && abs(ss->staticEval) > 78) + && depth > 10 + && abs(ss->staticEval) > 88) extension = 1; // Quiet ttMove extensions (~1 Elo) else if ( PvNode && move == ttMove && move == ss->killers[0] - && (*contHist[0])[movedPiece][to_sq(move)] >= 5600) + && (*contHist[0])[movedPiece][to_sq(move)] >= 5705) extension = 1; } @@ -1155,7 +1155,7 @@ moves_loop: // When in check, search starts here // Decrease reduction for PvNodes based on depth if (PvNode) - r -= 1 + 11 / (3 + depth); + r -= 1 + 12 / (3 + depth); // Decrease reduction if ttMove has been singularly extended (~1 Elo) if (singularQuietLMR) @@ -1172,17 +1172,17 @@ moves_loop: // When in check, search starts here // Decrease reduction if move is a killer and we have a good history if (move == ss->killers[0] - && (*contHist[0])[movedPiece][to_sq(move)] >= 3600) + && (*contHist[0])[movedPiece][to_sq(move)] >= 3722) r--; ss->statScore = 2 * thisThread->mainHistory[us][from_to(move)] + (*contHist[0])[movedPiece][to_sq(move)] + (*contHist[1])[movedPiece][to_sq(move)] + (*contHist[3])[movedPiece][to_sq(move)] - - 4467; + - 4182; // Decrease/increase reduction for moves with a good/bad history (~30 Elo) - r -= ss->statScore / (12800 + 4410 * (depth > 7 && depth < 19)); + r -= ss->statScore / (11791 + 3992 * (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 @@ -1206,8 +1206,8 @@ moves_loop: // When in check, search starts here { // Adjust full depth search based on LMR results - if result // was good enough search deeper, if it was bad enough search shallower - const bool doDeeperSearch = value > (alpha + 66 + 11 * (newDepth - d)); - const bool doEvenDeeperSearch = value > alpha + 582 && ss->doubleExtensions <= 5; + const bool doDeeperSearch = value > (alpha + 58 + 12 * (newDepth - d)); + const bool doEvenDeeperSearch = value > alpha + 588 && ss->doubleExtensions <= 5; const bool doShallowerSearch = value < bestValue + newDepth; ss->doubleExtensions = ss->doubleExtensions + doEvenDeeperSearch; @@ -1318,8 +1318,8 @@ moves_loop: // When in check, search starts here // Reduce other moves if we have found at least one score improvement if ( depth > 1 && depth < 6 - && beta < VALUE_KNOWN_WIN - && alpha > -VALUE_KNOWN_WIN) + && beta < 10534 + && alpha > -10534) depth -= 1; assert(depth > 0); @@ -1374,7 +1374,7 @@ moves_loop: // When in check, search starts here else if (!priorCapture) { // Extra bonuses for PV/Cut nodes or bad fail lows - int bonus = (depth > 4) + (PvNode || cutNode) + (bestValue < alpha - 88 * depth); + int bonus = (depth > 5) + (PvNode || cutNode) + (bestValue < alpha - 97 * depth); update_continuation_histories(ss-1, pos.piece_on(prevSq), prevSq, stat_bonus(depth) * bonus); } @@ -1502,7 +1502,7 @@ moves_loop: // When in check, search starts here if (PvNode && bestValue > alpha) alpha = bestValue; - futilityBase = bestValue + 158; + futilityBase = bestValue + 168; } const PieceToHistory* contHist[] = { (ss-1)->continuationHistory, (ss-2)->continuationHistory, @@ -1575,7 +1575,7 @@ 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, Value(-108))) + if (!pos.see_ge(move, Value(-110))) continue; } @@ -1708,7 +1708,7 @@ moves_loop: // When in check, search starts here if (!pos.capture(bestMove)) { - int bonus2 = bestValue > beta + 146 ? bonus1 // larger bonus + int bonus2 = bestValue > beta + 153 ? bonus1 // larger bonus : stat_bonus(depth); // smaller bonus // Increase stats for the best move in case it was a quiet move