From a12dc6cc1fdf754fd061780548d57fa89d92f59d Mon Sep 17 00:00:00 2001 From: FauziAkram Date: Sun, 10 May 2026 11:49:00 +0200 Subject: [PATCH] VVLTC parameter's tune MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Passed 1st VVLTC test with STC-bounds: LLR: 2.95 (-2.94,2.94) <0.00,2.00> Total: 78172 W: 20207 L: 19894 D: 38071 Ptnml(0-2): 2, 6871, 25032, 7174, 7 https://tests.stockfishchess.org/tests/view/69fa262f3a3c3e525bb2b5e7 Passed 2nd VVLTC test with LTC-bounds: LLR: 2.95 (-2.94,2.94) <0.50,2.50> Total: 44360 W: 11624 L: 11322 D: 21414 Ptnml(0-2): 0, 3931, 14022, 4221, 6 https://tests.stockfishchess.org/tests/view/69f8b30d3a3c3e525bb2b3d9 STC estimate test: Elo: -1.50 ± 1.5 (95%) LOS: 2.3% Total: 55742 W: 14169 L: 14409 D: 27164 Ptnml(0-2): 143, 6697, 14452, 6415, 164 nElo: -2.95 ± 2.9 (95%) PairsRatio: 0.96 https://tests.stockfishchess.org/tests/view/69fef06c9392f0c317213dca closes https://github.com/official-stockfish/Stockfish/pull/6807 Bench: 2619968 --- src/search.cpp | 220 +++++++++++++++++++++++++------------------------ 1 file changed, 111 insertions(+), 109 deletions(-) diff --git a/src/search.cpp b/src/search.cpp index 9e075a21c..088319104 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -90,11 +90,13 @@ int correction_value(const Worker& w, const Position& pos, const Stack* const ss const int wnpcv = shared.nonpawn_correction_entry(pos)[us].nonPawnWhite; const int bnpcv = shared.nonpawn_correction_entry(pos)[us].nonPawnBlack; const int cntcv = - m.is_ok() ? (*(ss - 2)->continuationCorrectionHistory)[pos.piece_on(m.to_sq())][m.to_sq()] - + (*(ss - 4)->continuationCorrectionHistory)[pos.piece_on(m.to_sq())][m.to_sq()] - : 8; + m.is_ok() + ? 8363 + * ((*(ss - 2)->continuationCorrectionHistory)[pos.piece_on(m.to_sq())][m.to_sq()] + + (*(ss - 4)->continuationCorrectionHistory)[pos.piece_on(m.to_sq())][m.to_sq()]) + : 64549; - return 12153 * pcv + 8620 * micv + 12355 * (wnpcv + bnpcv) + 7982 * cntcv; + return 13345 * pcv + 9280 * micv + 11840 * (wnpcv + bnpcv) + cntcv; } // Add correctionHistory value to raw staticEval and guarantee evaluation @@ -110,11 +112,11 @@ void update_correction_history(const Position& pos, const Move m = (ss - 1)->currentMove; const Color us = pos.side_to_move(); - constexpr int nonPawnWeight = 187; + constexpr int nonPawnWeight = 186; auto& shared = workerThread.sharedHistory; shared.pawn_correction_entry(pos)[us].pawn << bonus; - shared.minor_piece_correction_entry(pos)[us].minor << bonus * 153 / 128; + shared.minor_piece_correction_entry(pos)[us].minor << bonus * 152 / 128; shared.nonpawn_correction_entry(pos)[us].nonPawnWhite << bonus * nonPawnWeight / 128; shared.nonpawn_correction_entry(pos)[us].nonPawnBlack << bonus * nonPawnWeight / 128; @@ -122,8 +124,8 @@ void update_correction_history(const Position& pos, { const Square to = m.to_sq(); const Piece pc = pos.piece_on(to); - (*(ss - 2)->continuationCorrectionHistory)[pc][to] << bonus * 126 / 128; - (*(ss - 4)->continuationCorrectionHistory)[pc][to] << bonus * 63 / 128; + (*(ss - 2)->continuationCorrectionHistory)[pc][to] << bonus * 136 / 128; + (*(ss - 4)->continuationCorrectionHistory)[pc][to] << bonus * 68 / 128; } } @@ -145,9 +147,9 @@ void update_all_stats(const Position& pos, Move ttMove); bool is_shuffling(Move move, Stack* const ss, const Position& pos) { - if (pos.capture_stage(move) || pos.rule50_count() < 11) + if (pos.capture_stage(move) || pos.rule50_count() < 10) return false; - if (pos.state()->pliesFromNull <= 6 || ss->ply < 18) + if (pos.state()->pliesFromNull < 6 || ss->ply < 20) return false; return move.from_sq() == (ss - 2)->currentMove.to_sq() && (ss - 2)->currentMove.from_sq() == (ss - 4)->currentMove.to_sq(); @@ -315,11 +317,11 @@ bool Search::Worker::iterative_deepening() { int searchAgainCounter = 0; bool uciPvSent = false; - lowPlyHistory.fill(98); + lowPlyHistory.fill(100); for (Color c : {WHITE, BLACK}) for (int i = 0; i < UINT_16_HISTORY_SIZE; i++) - mainHistory[c][i] = mainHistory[c][i] * 820 / 1024; + mainHistory[c][i] = (mainHistory[c][i] + 5) * 789 / 1024; // Iterative deepening loop until requested to stop or the target depth is reached while (rootDepth + 1 < MAX_PLY && !threads.stop @@ -360,13 +362,13 @@ bool Search::Worker::iterative_deepening() { selDepth = 0; // Reset aspiration window starting size - delta = 5 + threadIdx % 8 + std::abs(rootMoves[pvIdx].meanSquaredScore) / 10208; + delta = 5 + threadIdx % 8 + std::abs(rootMoves[pvIdx].meanSquaredScore) / 10588; Value avg = rootMoves[pvIdx].averageScore; alpha = std::max(avg - delta, -VALUE_INFINITE); beta = std::min(avg + delta, VALUE_INFINITE); // Adjust optimism based on root move's averageScore - optimism[us] = 144 * avg / (std::abs(avg) + 91); + optimism[us] = 137 * avg / (std::abs(avg) + 81); optimism[~us] = -optimism[us]; // Start with a small aspiration window and, in the case of a fail @@ -423,7 +425,7 @@ bool Search::Worker::iterative_deepening() { else break; - delta += delta / 3; + delta += 44 * delta / 128; assert(alpha >= -VALUE_INFINITE && beta <= VALUE_INFINITE); } @@ -516,30 +518,30 @@ bool Search::Worker::iterative_deepening() { uint64_t nodesEffort = rootMoves[0].effort * 100000 / std::max(uint64_t(1), uint64_t(nodes)); - double fallingEval = (12.44 + 2.318 * (mainThread->bestPreviousAverageScore - bestValue) - + 0.95 * (mainThread->iterValue[iterIdx] - bestValue)) + double fallingEval = (11.87 + 2.21 * (mainThread->bestPreviousAverageScore - bestValue) + + 1.0 * (mainThread->iterValue[iterIdx] - bestValue)) / 100.0; - fallingEval = std::clamp(fallingEval, 0.581, 1.655); + fallingEval = std::clamp(fallingEval, 0.572, 1.708); // If the bestMove is stable over several iterations, reduce time accordingly timeReduction = std::clamp(interpolate(double(rootDepth - lastBestMoveDepth), 5.0, 18.0, 0.65, 1.55), 0.65, 1.55); - double reduction = (1.5 + mainThread->previousTimeReduction) / (2.255 * timeReduction); + double reduction = (1.48 + mainThread->previousTimeReduction) / (2.157 * timeReduction); - double bestMoveInstability = 1.088 + 2.315 * totBestMoveChanges / threads.size(); + double bestMoveInstability = 1.096 + 2.29 * totBestMoveChanges / threads.size(); double highBestMoveEffort = std::clamp( - interpolate(int64_t(nodesEffort), int64_t(78000), int64_t(94000), 0.96, 0.74), 0.74, - 0.96); + interpolate(int64_t(nodesEffort), int64_t(79219), int64_t(101822), 0.924, 0.71), 0.71, + 0.924); double totalTime = mainThread->tm.optimum() * fallingEval * reduction * bestMoveInstability * highBestMoveEffort; // Cap used time in case of a single legal move for a better viewer experience if (rootMoves.size() == 1) - totalTime = std::min(504.4, totalTime); + totalTime = std::min(561.7, totalTime); auto elapsedTime = elapsed(); @@ -616,27 +618,27 @@ void Search::Worker::undo_null_move(Position& pos) { pos.undo_null_move(); } // Reset histories, usually before a new game void Search::Worker::clear() { - mainHistory.fill(0); - captureHistory.fill(-678); + mainHistory.fill(-5); + captureHistory.fill(-699); // Each thread is responsible for clearing their part of shared history - sharedHistory.correctionHistory.clear_range(0, numaThreadIdx, numaTotal); - sharedHistory.pawnHistory.clear_range(-1238, numaThreadIdx, numaTotal); + sharedHistory.correctionHistory.clear_range(-6, numaThreadIdx, numaTotal); + sharedHistory.pawnHistory.clear_range(-1262, numaThreadIdx, numaTotal); ttMoveHistory = 0; for (auto& to : continuationCorrectionHistory) for (auto& h : to) - h.fill(6); + h.fill(5); for (bool inCheck : {false, true}) for (StatsType c : {NoCaptures, Captures}) for (auto& to : continuationHistory[inCheck][c]) for (auto& h : to) - h.fill(-523); + h.fill(-552); for (size_t i = 1; i < reductions.size(); ++i) - reductions[i] = int(2763 / 128.0 * std::log(i)); + reductions[i] = int(2834 / 128.0 * std::log(i)); refreshTable.clear(network[numaAccessToken]); } @@ -789,14 +791,14 @@ Value Search::Worker::search( // Hindsight adjustment of reductions based on static evaluation difference. if (priorReduction >= 3 && !opponentWorsening) depth++; - if (priorReduction >= 2 && depth >= 2 && ss->staticEval + (ss - 1)->staticEval > 195) + if (priorReduction >= 2 && depth >= 2 && ss->staticEval + (ss - 1)->staticEval > 173) depth--; // At non-PV nodes we check for an early TT cutoff if (!PvNode && !excludedMove && ttData.depth > depth - (ttData.value <= beta) && is_valid(ttData.value) // Can happen when !ttHit or when access race in probe() && (ttData.bound & (ttData.value >= beta ? BOUND_LOWER : BOUND_UPPER)) - && (cutNode == (ttData.value >= beta) || depth > 5)) + && (cutNode == (ttData.value >= beta) || depth > 4)) { // If ttMove is quiet, update move sorting heuristics on TT hit if (ttData.move && ttData.value >= beta) @@ -804,11 +806,11 @@ Value Search::Worker::search( // Bonus for a quiet ttMove that fails high if (!ttCapture) update_quiet_histories(pos, ss, *this, ttData.move, - std::min(119 * depth - 74, 855)); + std::min(114 * depth - 73, 797)); // Extra penalty for early quiet moves of the previous ply if (prevSq != SQ_NONE && (ss - 1)->moveCount < 4 && !priorCapture) - update_continuation_histories(ss - 1, pos.piece_on(prevSq), prevSq, -2014); + update_continuation_histories(ss - 1, pos.piece_on(prevSq), prevSq, -2187); } // Partial workaround for the graph history interaction problem @@ -895,38 +897,38 @@ Value Search::Worker::search( // Use static evaluation difference to improve quiet move ordering if (((ss - 1)->currentMove).is_ok() && !(ss - 1)->inCheck && !priorCapture) { - int evalDiff = std::clamp(-int((ss - 1)->staticEval + ss->staticEval), -214, 171) + 60; + int evalDiff = std::clamp(-int((ss - 1)->staticEval + ss->staticEval), -183, 180) + 62; mainHistory[~us][((ss - 1)->currentMove).raw()] << evalDiff * 10; if (!ttHit && type_of(pos.piece_on(prevSq)) != PAWN && ((ss - 1)->currentMove).type_of() != PROMOTION) - sharedHistory.pawn_entry(pos)[pos.piece_on(prevSq)][prevSq] << evalDiff * 12; + sharedHistory.pawn_entry(pos)[pos.piece_on(prevSq)][prevSq] << evalDiff * 13; } // Step 7. Razoring // If eval is really low, skip search entirely and return the qsearch value. // For PvNodes, we must have a guard against mates being returned. - if (!PvNode && eval < alpha - 502 - 306 * depth * depth) + if (!PvNode && eval < alpha - 465 - 300 * depth * depth) return qsearch(pos, ss, alpha, beta); // Step 8. Futility pruning: child node // The depth condition is important for mate finding. - if (!ss->ttPv && depth < 15 && eval >= beta && (!ttData.move || ttCapture) && !is_loss(beta) + if (!ss->ttPv && depth < 17 && eval >= beta && (!ttData.move || ttCapture) && !is_loss(beta) && !is_win(eval)) { - Value futilityMult = interpolate(std::min(int(depth), 10), 1, 10, 40, 76); - futilityMult -= 21 * !ss->ttHit; + Value futilityMult = interpolate(std::min(int(depth), 10), 1, 10, 40, 80); + futilityMult -= 20 * !ss->ttHit; Value futilityMargin = futilityMult * depth - - (2686 * improving + 362 * opponentWorsening) * futilityMult / 1024 - + std::abs(correctionValue) / 180600; + - (2934 * improving + 343 * opponentWorsening) * futilityMult / 1024 + + std::abs(correctionValue) / 182069; if (eval - futilityMargin >= beta) - return (2 * beta + eval) / 3; + return (716 * beta + 308 * eval) / 1024; } // Step 9. Null move search with verification search - if (cutNode && ss->staticEval >= beta - 16 * depth - 53 * improving + 378 && !excludedMove + if (cutNode && ss->staticEval >= beta - 14 * depth - 45 * improving + 374 && !excludedMove && pos.non_pawn_material(us) && ss->ply >= nmpMinPly && !is_loss(beta)) { assert((ss - 1)->currentMove != Move::null()); @@ -971,7 +973,7 @@ Value Search::Worker::search( // Step 11. ProbCut // If we have a good enough capture (or queen promotion) and a reduced search // returns a value much above beta, we can (almost) safely prune the previous move. - probCutBeta = beta + 224 - 61 * improving; + probCutBeta = beta + 214 - 59 * improving; if (depth >= 3 && !is_decisive(beta) // If value from transposition table is lower than probCutBeta, don't attempt @@ -1019,7 +1021,7 @@ Value Search::Worker::search( moves_loop: // When in check, search starts here // Step 12. A small Probcut idea - probCutBeta = beta + 416; + probCutBeta = beta + 428; if ((ttData.bound & BOUND_LOWER) && ttData.depth >= depth - 4 && ttData.value >= probCutBeta && !is_decisive(beta) && is_valid(ttData.value) && !is_decisive(ttData.value)) return probCutBeta; @@ -1080,7 +1082,7 @@ moves_loop: // When in check, search starts here // Increase reduction for ttPv nodes (*Scaler) // Larger values scale well if (ss->ttPv) - r += 1013; + r += 1006; // Step 14. Pruning at shallow depths. // Depth conditions are important for mate finding. @@ -1101,7 +1103,7 @@ moves_loop: // When in check, search starts here // Futility pruning for captures if (!givesCheck && lmrDepth < 7) { - Value futilityValue = ss->staticEval + 218 + 223 * lmrDepth + Value futilityValue = ss->staticEval + 231 + 232 * lmrDepth + PieceValue[capturedPiece] + 131 * captHist / 1024; if (futilityValue <= alpha) @@ -1110,7 +1112,7 @@ moves_loop: // When in check, search starts here // SEE based pruning for captures and checks // Avoid pruning sacrifices of our last piece for stalemate - int margin = std::max(167 * depth + captHist * 34 / 1024, 0); + int margin = std::max(175 * depth + captHist * 34 / 1024, 0); if ((alpha >= VALUE_DRAW || pos.non_pawn_material(us) != PieceValue[movedPiece]) && !pos.see_ge(move, -margin)) continue; @@ -1123,21 +1125,21 @@ moves_loop: // When in check, search starts here + sharedHistory.pawn_entry(pos)[movedPiece][move.to_sq()]; // Continuation history based pruning - if (history < -4097 * depth) + if (history < -4313 * depth) continue; - history += 71 * mainHistory[us][move.raw()] / 32; + history += 64 * mainHistory[us][move.raw()] / 32; // (*Scaler): Generally, lower divisors scale well lmrDepth += history / lmrDivisor[dIndex]; - Value futilityValue = ss->staticEval + 42 + 151 * !bestMove + 120 * lmrDepth - + 86 * (ss->staticEval > alpha); + Value futilityValue = ss->staticEval + 40 + 138 * !bestMove + 117 * lmrDepth + + 90 * (ss->staticEval > alpha); // Futility pruning: parent node // (*Scaler): Generally, more frequent futility pruning // scales well - if (!ss->inCheck && lmrDepth < 13 && futilityValue <= alpha) + if (!ss->inCheck && lmrDepth < 12 && futilityValue <= alpha) { if (bestValue <= futilityValue && !is_decisive(bestValue) && !is_win(futilityValue)) @@ -1167,7 +1169,7 @@ moves_loop: // When in check, search starts here && is_valid(ttData.value) && !is_decisive(ttData.value) && (ttData.bound & BOUND_LOWER) && ttData.depth >= depth - 3 && !is_shuffling(move, ss, pos)) { - Value singularBeta = ttData.value - (60 + 66 * (ss->ttPv && !PvNode)) * depth / 55; + Value singularBeta = ttData.value - (60 + 70 * (ss->ttPv && !PvNode)) * depth / 59; Depth singularDepth = newDepth / 2; ss->excludedMove = move; @@ -1176,10 +1178,10 @@ moves_loop: // When in check, search starts here if (value < singularBeta) { - int corrValAdj = std::abs(correctionValue) / 210590; - int doubleMargin = -4 + 212 * PvNode - 182 * !ttCapture - corrValAdj - - 906 * ttMoveHistory / 116517 - (ss->ply > rootDepth) * 44; - int tripleMargin = 73 + 320 * PvNode - 218 * !ttCapture + 92 * ss->ttPv - corrValAdj + int corrValAdj = std::abs(correctionValue) / 194822; + int doubleMargin = -3 + 201 * PvNode - 157 * !ttCapture - corrValAdj + - 1081 * ttMoveHistory / 117824 - (ss->ply > rootDepth) * 41; + int tripleMargin = 72 + 306 * PvNode - 188 * !ttCapture + 84 * ss->ttPv - corrValAdj - (ss->ply > rootDepth) * 45; extension = @@ -1196,7 +1198,7 @@ moves_loop: // When in check, search starts here // subtree by returning a softbound. else if (value >= beta && !is_decisive(value)) { - ttMoveHistory << -424 - 107 * depth; + ttMoveHistory << -442 - 108 * depth; return value; } @@ -1227,31 +1229,31 @@ moves_loop: // When in check, search starts here // Decrease reduction for PvNodes (*Scaler) if (ss->ttPv) - r -= 2617 + PvNode * 912 + (ttData.value > alpha) * 934 - + (ttData.depth >= depth) * (988 + cutNode * 889); + r -= 2766 + PvNode * 1017 + (ttData.value > alpha) * 838 + + (ttData.depth >= depth) * (923 + cutNode * 955); - r += 691; // Base reduction offset to compensate for other tweaks - r -= moveCount * 65; - r -= std::abs(correctionValue) / 25600; + r += 714; // Base reduction offset to compensate for other tweaks + r -= moveCount * 62; + r -= std::abs(correctionValue) / 26131; // Increase reduction for cut nodes if (cutNode) - r += 3274 + 1006 * !ttData.move; + r += 3995 + 1059 * !ttData.move; // Increase reduction if ttMove is a capture if (ttCapture) - r += 1054; + r += 1039; // Increase reduction if next ply has a lot of fail high if ((ss + 1)->cutoffCnt > 1) - r += 251 + 1124 * ((ss + 1)->cutoffCnt > 2) + 1042 * allNode; + r += 236 + 1079 * ((ss + 1)->cutoffCnt > 2) + 1143 * allNode; // For first picked move (ttMove) reduce reduction else if (move == ttData.move) r = std::max(-10, r - 2016 + 150 * cutNode); if (capture) - ss->statScore = 863 * int(PieceValue[pos.captured_piece()]) / 128 + ss->statScore = 809 * int(PieceValue[pos.captured_piece()]) / 128 + captureHistory[movedPiece][move.to_sq()][type_of(pos.captured_piece())]; else ss->statScore = 2 * mainHistory[us][move.raw()] @@ -1259,11 +1261,11 @@ moves_loop: // When in check, search starts here + (*contHist[1])[movedPiece][move.to_sq()]; // Decrease/increase reduction for moves with a good/bad history - r -= ss->statScore * 428 / 4096; + r -= ss->statScore * 445 / 4096; // Scale up reductions for expected ALL nodes if (allNode) - r += r * 273 / (256 * depth + 260); + r += r * 272 / (256 * depth + 285); // Step 17. Late moves reduction / extension (LMR) if (depth >= 2 && moveCount > 1) @@ -1285,7 +1287,7 @@ moves_loop: // When in check, search starts here { // Adjust full-depth search based on LMR results - if the result was // good enough search deeper, if it was bad enough search shallower. - const bool doDeeperSearch = d < newDepth && value > bestValue + 48; + const bool doDeeperSearch = d < newDepth && value > bestValue + 52; const bool doShallowerSearch = value < bestValue + 9; newDepth += doDeeperSearch - doShallowerSearch; @@ -1294,7 +1296,7 @@ moves_loop: // When in check, search starts here value = -search(pos, ss + 1, -(alpha + 1), -alpha, newDepth, !cutNode); // Post LMR continuation history updates - update_continuation_histories(ss, movedPiece, move.to_sq(), 1426); + update_continuation_histories(ss, movedPiece, move.to_sq(), 1415); } } @@ -1303,11 +1305,11 @@ moves_loop: // When in check, search starts here { // Increase reduction if ttMove is not present if (!ttData.move) - r += 1057; + r += 1085; // Note that if expected reduction is high, we reduce search depth here value = -search(pos, ss + 1, -(alpha + 1), -alpha, - newDepth - (r > 4628) - (r > 5772 && newDepth > 2), !cutNode); + newDepth - (r > 5039) - (r > 5223 && newDepth > 2), !cutNode); } // For PV nodes only, do a full PV search on the first move or after a fail high, @@ -1415,7 +1417,7 @@ moves_loop: // When in check, search starts here } // Reduce other moves if we have found at least one score improvement - if (depth > 2 && depth < 14 && !is_decisive(value)) + if (depth > 2 && depth < 13 && !is_decisive(value)) depth -= 2; assert(depth > 0); @@ -1455,31 +1457,31 @@ moves_loop: // When in check, search starts here update_all_stats(pos, ss, *this, bestMove, prevSq, quietsSearched, capturesSearched, depth, ttData.move); if (!PvNode) - ttMoveHistory << (bestMove == ttData.move ? 805 : -787); + ttMoveHistory << (bestMove == ttData.move ? 792 : -779); } // Bonus for prior quiet countermove that caused the fail low else if (!priorCapture && prevSq != SQ_NONE) { - int bonusScale = -232; - bonusScale -= (ss - 1)->statScore / 108; - bonusScale += std::min(59 * depth, 454); - bonusScale += 169 * ((ss - 1)->moveCount > 8); - bonusScale += 145 * (!ss->inCheck && bestValue <= ss->staticEval - 110); - bonusScale += 154 * (!(ss - 1)->inCheck && bestValue <= -(ss - 1)->staticEval - 73); + int bonusScale = -245; + bonusScale -= (ss - 1)->statScore / 98; + bonusScale += std::min(59 * depth, 430); + bonusScale += 191 * ((ss - 1)->moveCount > 8); + bonusScale += 143 * (!ss->inCheck && bestValue <= ss->staticEval - 103); + bonusScale += 151 * (!(ss - 1)->inCheck && bestValue <= -(ss - 1)->staticEval - 78); bonusScale = std::max(bonusScale, 0); // scaledBonus ranges from 0 to roughly 2.3M, overflows happen for multipliers larger than 900 - const int scaledBonus = std::min(135 * depth - 80, 1400) * bonusScale; + const int scaledBonus = std::min(141 * depth - 82, 1472) * bonusScale; update_continuation_histories(ss - 1, pos.piece_on(prevSq), prevSq, - scaledBonus * 221 / 16384); + scaledBonus * 236 / 16384); - mainHistory[~us][((ss - 1)->currentMove).raw()] << scaledBonus * 235 / 32768; + mainHistory[~us][((ss - 1)->currentMove).raw()] << scaledBonus * 234 / 32768; if (type_of(pos.piece_on(prevSq)) != PAWN && ((ss - 1)->currentMove).type_of() != PROMOTION) - sharedHistory.pawn_entry(pos)[pos.piece_on(prevSq)][prevSq] << scaledBonus * 290 / 8192; + sharedHistory.pawn_entry(pos)[pos.piece_on(prevSq)][prevSq] << scaledBonus * 322 / 8192; } // Bonus for prior capture countermove that caused the fail low @@ -1487,7 +1489,7 @@ moves_loop: // When in check, search starts here { Piece capturedPiece = pos.captured_piece(); assert(capturedPiece != NO_PIECE); - captureHistory[pos.piece_on(prevSq)][prevSq][type_of(capturedPiece)] << 1018; + captureHistory[pos.piece_on(prevSq)][prevSq][type_of(capturedPiece)] << 901; } if (PvNode) @@ -1514,9 +1516,9 @@ moves_loop: // When in check, search starts here && (bestValue > ss->staticEval) == bool(bestMove)) { auto bonus = - std::clamp(int(bestValue - ss->staticEval) * depth * (bestMove ? 12 : 17) / 128, + std::clamp(int(bestValue - ss->staticEval) * depth * (bestMove ? 12 : 18) / 128, -CORRECTION_HISTORY_LIMIT / 4, CORRECTION_HISTORY_LIMIT / 4); - update_correction_history(pos, ss, *this, 1069 * bonus / 1024); + update_correction_history(pos, ss, *this, 1114 * bonus / 1024); } assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE); @@ -1628,7 +1630,7 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta) if (bestValue >= beta) { if (!is_decisive(bestValue)) - bestValue = (bestValue + beta) / 2; + bestValue = (467 * bestValue + 557 * beta) / 1024; if (!ss->ttHit) ttWriter.write(posKey, VALUE_NONE, false, BOUND_LOWER, DEPTH_UNSEARCHED, @@ -1639,7 +1641,7 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta) if (bestValue > alpha) alpha = bestValue; - futilityBase = ss->staticEval + 328; + futilityBase = ss->staticEval + 335; } const PieceToHistory* contHist[] = {(ss - 1)->continuationHistory}; @@ -1700,7 +1702,7 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta) continue; // Do not search moves with bad enough SEE values - if (!pos.see_ge(move, -73)) + if (!pos.see_ge(move, -74)) continue; } @@ -1752,7 +1754,7 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta) } if (!is_decisive(bestValue) && bestValue > beta) - bestValue = (bestValue + beta) / 2; + bestValue = (481 * bestValue + 543 * beta) / 1024; // Save gathered info in transposition table. The static evaluation // is saved as it was before adjustment by correction history. @@ -1767,7 +1769,7 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta) int Search::Worker::reduction(bool i, Depth d, int mn, int delta) const { int reductionScale = reductions[d] * reductions[mn]; - return reductionScale - delta * 585 / rootDelta + !i * reductionScale * 206 / 512 + 1133; + return reductionScale - delta * 617 / rootDelta + !i * reductionScale * 194 / 512 + 1027; } // elapsed() returns the time elapsed since the search started. If the @@ -1854,18 +1856,18 @@ void update_all_stats(const Position& pos, PieceType capturedPiece; int bonus = - std::min(128 * depth - 77, 1529) + 353 * (bestMove == ttMove) + (ss - 1)->statScore / 32; - int malus = std::min(882 * depth - 204, 2122); + std::min(134 * depth - 79, 1572) + 382 * (bestMove == ttMove) + (ss - 1)->statScore / 30; + int malus = std::min(1005 * depth - 205, 2218); if (!pos.capture_stage(bestMove)) { - update_quiet_histories(pos, ss, workerThread, bestMove, bonus * 806 / 1024); + update_quiet_histories(pos, ss, workerThread, bestMove, bonus * 824 / 1024); - int actualMalus = malus * 1113 / 1024; + int actualMalus = malus * 1136 / 1024; // Decrease stats for all non-best quiet moves for (Move move : quietsSearched) { - actualMalus = actualMalus * 977 / 1024; + actualMalus = actualMalus * 956 / 1024; update_quiet_histories(pos, ss, workerThread, move, -actualMalus); } } @@ -1873,20 +1875,20 @@ void update_all_stats(const Position& pos, { // Increase stats for the best move in case it was a capture move capturedPiece = type_of(pos.piece_on(bestMove.to_sq())); - captureHistory[movedPiece][bestMove.to_sq()][capturedPiece] << bonus * 1286 / 1024; + captureHistory[movedPiece][bestMove.to_sq()][capturedPiece] << bonus * 1366 / 1024; } // Extra penalty for a quiet early move that was not a TT move in // previous ply when it gets refuted. if (prevSq != SQ_NONE && ((ss - 1)->moveCount == 1 + (ss - 1)->ttHit) && !pos.captured_piece()) - update_continuation_histories(ss - 1, pos.piece_on(prevSq), prevSq, -malus * 616 / 1024); + update_continuation_histories(ss - 1, pos.piece_on(prevSq), prevSq, -malus * 683 / 1024); // Decrease stats for all non-best capture moves for (Move move : capturesSearched) { movedPiece = pos.moved_piece(move); capturedPiece = type_of(pos.piece_on(move.to_sq())); - captureHistory[movedPiece][move.to_sq()][capturedPiece] << -malus * 1559 / 1024; + captureHistory[movedPiece][move.to_sq()][capturedPiece] << -malus * 1518 / 1024; } } @@ -1895,10 +1897,10 @@ void update_all_stats(const Position& pos, // the current move and the moves played in previous plies. void update_continuation_histories(Stack* ss, Piece pc, Square to, int bonus) { static constexpr std::array conthist_bonuses = { - {{1, 1071}, {2, 753}, {3, 329}, {4, 539}, {5, 124}, {6, 434}}}; + {{1, 1040}, {2, 780}, {3, 300}, {4, 537}, {5, 129}, {6, 423}}}; // Multipliers for positive history consistency - constexpr int CMHCMultipliers[] = {96, 100, 100, 100, 115, 118, 129}; + constexpr int CMHCMultipliers[] = {96, 113, 101, 105, 127, 121, 126}; int positiveCount = 0; for (const auto [i, weight] : conthist_bonuses) @@ -1914,7 +1916,7 @@ void update_continuation_histories(Stack* ss, Piece pc, Square to, int bonus) { positiveCount++; int multiplier = CMHCMultipliers[positiveCount]; - historyEntry << (bonus * weight * multiplier / 131072) + 73 * (i < 2); + historyEntry << (bonus * weight * multiplier / 131072) + 71 * (i < 2); } } } @@ -1928,12 +1930,12 @@ void update_quiet_histories( workerThread.mainHistory[us][move.raw()] << bonus; // Untuned to prevent duplicate effort if (ss->ply < LOW_PLY_HISTORY_SIZE) - workerThread.lowPlyHistory[ss->ply][move.raw()] << bonus * 682 / 1024; + workerThread.lowPlyHistory[ss->ply][move.raw()] << bonus * 663 / 1024; - update_continuation_histories(ss, pos.moved_piece(move), move.to_sq(), bonus * 894 / 1024); + update_continuation_histories(ss, pos.moved_piece(move), move.to_sq(), bonus * 820 / 1024); workerThread.sharedHistory.pawn_entry(pos)[pos.moved_piece(move)][move.to_sq()] - << bonus * (bonus > 0 ? 974 : 543) / 1024; + << bonus * (bonus > -7 ? 1038 : 525) / 1024; } }