diff --git a/src/search.cpp b/src/search.cpp index 2b95043fd37..54990ce6f03 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -59,9 +59,9 @@ static constexpr double EvalLevel[10] = {0.981, 0.956, 0.895, 0.949, 0.913, // Futility margin Value futility_margin(Depth d, bool noTtCutNode, bool improving, bool oppWorsening) { - Value futilityMult = 131 - 48 * noTtCutNode; - Value improvingDeduction = 2 * improving * futilityMult; - Value worseningDeduction = 330 * oppWorsening * futilityMult / 1024; + Value futilityMult = 127 - 48 * noTtCutNode; + Value improvingDeduction = 65 * improving * futilityMult / 32; + Value worseningDeduction = 334 * oppWorsening * futilityMult / 1024; return futilityMult * d - improvingDeduction - worseningDeduction; } @@ -73,15 +73,15 @@ constexpr int futility_move_count(bool improving, Depth depth) { // Add correctionHistory value to raw staticEval and guarantee evaluation does not hit the tablebase range Value to_corrected_static_eval(Value v, const Worker& w, const Position& pos) { auto cv = w.correctionHistory[pos.side_to_move()][pawn_structure_index(pos)]; - v += cv * std::abs(cv) / 7179; + v += cv * std::abs(cv) / 6047; return std::clamp(v, VALUE_TB_LOSS_IN_MAX_PLY + 1, VALUE_TB_WIN_IN_MAX_PLY - 1); } // History and stats update bonus, based on depth -int stat_bonus(Depth d) { return std::clamp(200 * d - 280, 16, 1495); } +int stat_bonus(Depth d) { return std::clamp(187 * d - 288, 17, 1548); } // History and stats update malus, based on depth -int stat_malus(Depth d) { return (d < 4 ? 586 * d - 284 : 1639); } +int stat_malus(Depth d) { return (d < 4 ? 630 * d - 281 : 1741); } // Add a small random component to draw evaluations to avoid 3-fold blindness Value value_draw(size_t nodes) { return VALUE_DRAW - 1 + Value(nodes & 0x2); } @@ -311,12 +311,12 @@ void Search::Worker::iterative_deepening() { // Reset aspiration window starting size Value avg = rootMoves[pvIdx].averageScore; - delta = 10 + avg * avg / 9474; + delta = 10 + avg * avg / 9828; alpha = std::max(avg - delta, -VALUE_INFINITE); beta = std::min(avg + delta, VALUE_INFINITE); // Adjust optimism based on root move's averageScore (~4 Elo) - optimism[us] = 117 * avg / (std::abs(avg) + 88); + optimism[us] = 116 * avg / (std::abs(avg) + 84); optimism[~us] = -optimism[us]; // Start with a small aspiration window and, in the case of a fail @@ -503,10 +503,10 @@ void Search::Worker::clear() { for (StatsType c : {NoCaptures, Captures}) for (auto& to : continuationHistory[inCheck][c]) for (auto& h : to) - h->fill(-62); + h->fill(-60); for (size_t i = 1; i < reductions.size(); ++i) - reductions[i] = int((21.19 + std::log(size_t(options["Threads"])) / 2) * std::log(i)); + reductions[i] = int((21.69 + std::log(size_t(options["Threads"])) / 2) * std::log(i)); refreshTable.clear(networks); } @@ -739,7 +739,7 @@ Value Search::Worker::search( // Use static evaluation difference to improve quiet move ordering (~9 Elo) if (((ss - 1)->currentMove).is_ok() && !(ss - 1)->inCheck && !priorCapture) { - int bonus = std::clamp(-12 * int((ss - 1)->staticEval + ss->staticEval), -1749, 1584); + int bonus = std::clamp(-11 * int((ss - 1)->staticEval + ss->staticEval), -1729, 1517); bonus = bonus > 0 ? 2 * bonus : bonus / 2; thisThread->mainHistory[~us][((ss - 1)->currentMove).from_to()] << bonus; if (type_of(pos.piece_on(prevSq)) != PAWN && ((ss - 1)->currentMove).type_of() != PROMOTION) @@ -762,7 +762,7 @@ Value Search::Worker::search( // If eval is really low check with qsearch if it can exceed alpha, if it can't, // return a fail low. // Adjust razor margin according to cutoffCnt. (~1 Elo) - if (eval < alpha - 473 - (308 - 138 * ((ss + 1)->cutoffCnt > 3)) * depth * depth) + if (eval < alpha - 474 - (326 - 139 * ((ss + 1)->cutoffCnt > 3)) * depth * depth) { value = qsearch(pos, ss, alpha - 1, alpha); if (value < alpha) @@ -773,21 +773,21 @@ Value Search::Worker::search( // The depth condition is important for mate finding. if (!ss->ttPv && depth < 11 && eval - futility_margin(depth, cutNode && !ss->ttHit, improving, opponentWorsening) - - (ss - 1)->statScore / 258 + - (ss - 1)->statScore / 252 >= beta && eval >= beta && eval < VALUE_TB_WIN_IN_MAX_PLY && (!ttMove || ttCapture)) return beta > VALUE_TB_LOSS_IN_MAX_PLY ? (eval + beta) / 2 : eval; // Step 9. Null move search with verification search (~35 Elo) - if (!PvNode && (ss - 1)->currentMove != Move::null() && (ss - 1)->statScore < 16079 - && eval >= beta && ss->staticEval >= beta - 21 * depth + 324 && !excludedMove + if (!PvNode && (ss - 1)->currentMove != Move::null() && (ss - 1)->statScore < 15246 + && eval >= beta && ss->staticEval >= beta - 21 * depth + 366 && !excludedMove && pos.non_pawn_material(us) && ss->ply >= thisThread->nmpMinPly && beta > VALUE_TB_LOSS_IN_MAX_PLY) { assert(eval - beta >= 0); // Null move dynamic reduction based on depth and eval - Depth R = std::min(int(eval - beta) / 144, 6) + depth / 3 + 5; + Depth R = std::min(int(eval - beta) / 152, 6) + depth / 3 + 5; ss->currentMove = Move::null(); ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0]; @@ -835,7 +835,7 @@ Value Search::Worker::search( // Step 11. ProbCut (~10 Elo) // 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 + 177 - 65 * improving; + probCutBeta = beta + 176 - 65 * improving; if ( !PvNode && depth > 3 && std::abs(beta) < VALUE_TB_WIN_IN_MAX_PLY @@ -891,7 +891,7 @@ Value Search::Worker::search( moves_loop: // When in check, search starts here // Step 12. A small Probcut idea, when we are in check (~4 Elo) - probCutBeta = beta + 428; + probCutBeta = beta + 440; if (ss->inCheck && !PvNode && ttCapture && (tte->bound() & BOUND_LOWER) && tte->depth() >= depth - 4 && ttValue >= probCutBeta && std::abs(ttValue) < VALUE_TB_WIN_IN_MAX_PLY && std::abs(beta) < VALUE_TB_WIN_IN_MAX_PLY) @@ -975,15 +975,15 @@ Value Search::Worker::search( // Futility pruning for captures (~2 Elo) if (!givesCheck && lmrDepth < 7 && !ss->inCheck) { - Value futilityValue = ss->staticEval + 305 + 272 * lmrDepth + Value futilityValue = ss->staticEval + 276 + 256 * lmrDepth + PieceValue[capturedPiece] + captHist / 7; if (futilityValue <= alpha) continue; } // SEE based pruning for captures and checks (~11 Elo) - int seeHist = std::clamp(captHist / 32, -185 * depth, 182 * depth); - if (!pos.see_ge(move, -176 * depth - seeHist)) + int seeHist = std::clamp(captHist / 32, -177 * depth, 175 * depth); + if (!pos.see_ge(move, -183 * depth - seeHist)) continue; } else @@ -994,18 +994,18 @@ Value Search::Worker::search( + thisThread->pawnHistory[pawn_structure_index(pos)][movedPiece][move.to_sq()]; // Continuation history based pruning (~2 Elo) - if (lmrDepth < 6 && history < -4360 * depth) + if (lmrDepth < 6 && history < -4076 * depth) continue; history += 2 * thisThread->mainHistory[us][move.from_to()]; - lmrDepth += history / 4507; + lmrDepth += history / 4401; Value futilityValue = - ss->staticEval + (bestValue < ss->staticEval - 54 ? 142 : 55) + 132 * lmrDepth; + ss->staticEval + (bestValue < ss->staticEval - 53 ? 151 : 57) + 140 * lmrDepth; // Futility pruning: parent node (~13 Elo) - if (!ss->inCheck && lmrDepth < 11 && futilityValue <= alpha) + if (!ss->inCheck && lmrDepth < 10 && futilityValue <= alpha) { if (bestValue <= futilityValue && std::abs(bestValue) < VALUE_TB_WIN_IN_MAX_PLY && futilityValue < VALUE_TB_WIN_IN_MAX_PLY) @@ -1016,7 +1016,7 @@ Value Search::Worker::search( lmrDepth = std::max(lmrDepth, 0); // Prune moves with negative SEE (~4 Elo) - if (!pos.see_ge(move, -27 * lmrDepth * lmrDepth)) + if (!pos.see_ge(move, -26 * lmrDepth * lmrDepth)) continue; } } @@ -1036,11 +1036,11 @@ Value Search::Worker::search( // so changing them requires tests at these types of time controls. // Recursive singular search is avoided. if (!rootNode && move == ttMove && !excludedMove - && depth >= 4 - (thisThread->completedDepth > 33) + ss->ttPv + && depth >= 4 - (thisThread->completedDepth > 35) + ss->ttPv && std::abs(ttValue) < VALUE_TB_WIN_IN_MAX_PLY && (tte->bound() & BOUND_LOWER) && tte->depth() >= depth - 3) { - Value singularBeta = ttValue - (59 + 49 * (ss->ttPv && !PvNode)) * depth / 64; + Value singularBeta = ttValue - (57 + 50 * (ss->ttPv && !PvNode)) * depth / 64; Depth singularDepth = newDepth / 2; ss->excludedMove = move; @@ -1050,14 +1050,14 @@ Value Search::Worker::search( if (value < singularBeta) { - int doubleMargin = 285 * PvNode - 228 * !ttCapture; + int doubleMargin = 298 * PvNode - 209 * !ttCapture; int tripleMargin = - 121 + 238 * PvNode - 259 * !ttCapture + 117 * (ss->ttPv || !ttCapture); + 117 + 252 * PvNode - 270 * !ttCapture + 111 * (ss->ttPv || !ttCapture); extension = 1 + (value < singularBeta - doubleMargin) + (value < singularBeta - tripleMargin); - depth += ((!PvNode) && (depth < 14)); + depth += ((!PvNode) && (depth < 15)); } // Multi-cut pruning @@ -1092,7 +1092,7 @@ Value Search::Worker::search( else if (PvNode && move == ttMove && move.to_sq() == prevSq && thisThread->captureHistory[movedPiece][move.to_sq()] [type_of(pos.piece_on(move.to_sq()))] - > 4041) + > 3748) extension = 1; } @@ -1143,10 +1143,10 @@ Value Search::Worker::search( ss->statScore = 2 * thisThread->mainHistory[us][move.from_to()] + (*contHist[0])[movedPiece][move.to_sq()] - + (*contHist[1])[movedPiece][move.to_sq()] - 5313; + + (*contHist[1])[movedPiece][move.to_sq()] - 5266; // Decrease/increase reduction for moves with a good/bad history (~8 Elo) - r -= ss->statScore / (16145 - std::min(depth, 15) * 102); + r -= ss->statScore / (14519 - std::min(depth, 15) * 103); // Step 17. Late moves reduction / extension (LMR, ~117 Elo) if (depth >= 2 && moveCount > 1 + rootNode) @@ -1165,7 +1165,7 @@ Value Search::Worker::search( { // 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 = value > (bestValue + 41 + 2 * newDepth); // (~1 Elo) + const bool doDeeperSearch = value > (bestValue + 40 + 2 * newDepth); // (~1 Elo) const bool doShallowerSearch = value < bestValue + newDepth; // (~2 Elo) newDepth += doDeeperSearch - doShallowerSearch; @@ -1326,9 +1326,9 @@ Value Search::Worker::search( // Bonus for prior countermove that caused the fail low else if (!priorCapture && prevSq != SQ_NONE) { - int bonus = (depth > 4) + (depth > 5) + (PvNode || cutNode) + ((ss - 1)->statScore < -14323) - + ((ss - 1)->moveCount > 10) + (!ss->inCheck && bestValue <= ss->staticEval - 120) - + (!(ss - 1)->inCheck && bestValue <= -(ss - 1)->staticEval - 76); + int bonus = (depth > 4) + (depth > 5) + (PvNode || cutNode) + ((ss - 1)->statScore < -13241) + + ((ss - 1)->moveCount > 10) + (!ss->inCheck && bestValue <= ss->staticEval - 127) + + (!(ss - 1)->inCheck && bestValue <= -(ss - 1)->staticEval - 74); update_continuation_histories(ss - 1, pos.piece_on(prevSq), prevSq, stat_bonus(depth) * bonus); thisThread->mainHistory[~us][((ss - 1)->currentMove).from_to()] @@ -1494,7 +1494,7 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta, if (bestValue > alpha) alpha = bestValue; - futilityBase = ss->staticEval + 259; + futilityBase = ss->staticEval + 264; } const PieceToHistory* contHist[] = {(ss - 1)->continuationHistory, @@ -1566,11 +1566,11 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta, + (*contHist[1])[pos.moved_piece(move)][move.to_sq()] + thisThread->pawnHistory[pawn_structure_index(pos)][pos.moved_piece(move)] [move.to_sq()] - <= 4057) + <= 4348) continue; // Do not search moves with bad enough SEE values (~5 Elo) - if (!pos.see_ge(move, -68)) + if (!pos.see_ge(move, -63)) continue; } @@ -1636,7 +1636,7 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta, Depth Search::Worker::reduction(bool i, Depth d, int mn, int delta) { int reductionScale = reductions[d] * reductions[mn]; - return (reductionScale + 1284 - delta * 755 / rootDelta) / 1024 + (!i && reductionScale > 1133); + return (reductionScale + 1147 - delta * 755 / rootDelta) / 1024 + (!i && reductionScale > 1125); } // elapsed() returns the time elapsed since the search started. If the