diff --git a/src/evaluate.h b/src/evaluate.h index 6eafdd539f9..5a105870c54 100644 --- a/src/evaluate.h +++ b/src/evaluate.h @@ -39,7 +39,7 @@ extern std::string currentEvalFileName[2]; // for the build process (profile-build and fishtest) to work. Do not change the // name of the macro, as it is used in the Makefile. #define EvalFileDefaultNameBig "nn-0000000000a0.nnue" -#define EvalFileDefaultNameSmall "nn-ecb35f70ff2a.nnue" +#define EvalFileDefaultNameSmall "nn-9067e33176e8.nnue" namespace NNUE { diff --git a/src/search.cpp b/src/search.cpp index b0eb1eb8a26..132e70cd4bf 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -47,32 +47,6 @@ namespace Stockfish { -int -a1=125, a2=43, a3=1487, a4=976, a5=808, a6=291, a7=350, a8=1200, a9=361, a10=361, a11=1182, -b1=10, b2=15335, b3=110, b4=121, b5=14, b6=1449, b7=1449, -c1=474, c2=270, c3=174, c4=9, c5=321, c6=29462, c7=17257, c8=24, c9=281, c10=152, c11=14, c12=8, c13=168, c14=70, -d1=416, d2=7, d3=239, d4=291, d5=185, d6=6, d7=3645, d8=7836, d9=13, d10=62, d11=123, d12=77, d13=127, d14=26, -e1=24, e2=64, e3=57, e4=18, e5=11, e6=15, e7=19, e8=9, e9=4194, e10=4000, e11=7, e12=3848, e13=14200, -f1=50, f2=2, f3=2, f4=12, f5=13828, f6=11369, f7=6, f8=657, f9=10, -g1=200, g2=90, g3=168, g4=168; - -TUNE(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, - b1); -TUNE(SetRange(1, 30000), b2); -TUNE(b3, b4, b5, b6, b7, - c1, c2, c3, c4); -TUNE(SetRange(1, 600), c5); -TUNE(c6, c7, c8, c9); -TUNE(SetRange(1, 300), c10); -TUNE(c11, c12, c13, c14, - d1, d2, d3, d4, d5, d6, d7); -TUNE(SetRange(1, 15000), d8); -TUNE(d9, d10, d11, d12, d13, d14, - e1, e2, e3, e4, e5, e6, e7, e8, e9, e10, e11, e12); -TUNE(SetRange(1, 30000), e13); -TUNE(f1, f2, f3, f4, f5, f6, f7, f8, f9, - g1, g2, g3, g4); - namespace Search { LimitsType Limits; @@ -103,7 +77,7 @@ enum NodeType { // Futility margin Value futility_margin(Depth d, bool noTtCutNode, bool improving) { - return Value((a1 - a2 * noTtCutNode) * (d - improving)); + return Value((116 - 44 * noTtCutNode) * (d - improving)); } // Reductions lookup table initialized at startup @@ -111,8 +85,8 @@ int Reductions[MAX_MOVES]; // [depth or moveNumber] Depth reduction(bool i, Depth d, int mn, Value delta, Value rootDelta) { int reductionScale = Reductions[d] * Reductions[mn]; - return (reductionScale + a3 - int(delta) * a4 / int(rootDelta)) / 1024 - + (!i && reductionScale > a5); + return (reductionScale + 1346 - int(delta) * 896 / int(rootDelta)) / 1024 + + (!i && reductionScale > 880); } constexpr int futility_move_count(bool improving, Depth depth) { @@ -120,10 +94,10 @@ constexpr int futility_move_count(bool improving, Depth depth) { } // History and stats update bonus, based on depth -int stat_bonus(Depth d) { return std::min(a6 * d - a7, a8); } +int stat_bonus(Depth d) { return std::min(268 * d - 352, 1153); } // History and stats update malus, based on depth -int stat_malus(Depth d) { return std::min(a9 * d - a10, a11); } +int stat_malus(Depth d) { return std::min(400 * d - 354, 1201); } // Add a small random component to draw evaluations to avoid 3-fold blindness Value value_draw(const Thread* thisThread) { @@ -393,12 +367,12 @@ void Thread::search() { // Reset aspiration window starting size Value avg = rootMoves[pvIdx].averageScore; - delta = Value(b1) + int(avg) * avg / b2; + delta = Value(9) + int(avg) * avg / 14847; 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] = b3 * avg / (std::abs(avg) + b4); + optimism[us] = 121 * avg / (std::abs(avg) + 109); optimism[~us] = -optimism[us]; // Start with a small aspiration window and, in the case of a fail @@ -772,7 +746,7 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo // 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(-b5 * int((ss - 1)->staticEval + ss->staticEval), -b6, b7); + int bonus = std::clamp(-13 * int((ss - 1)->staticEval + ss->staticEval), -1555, 1452); thisThread->mainHistory[~us][from_to((ss - 1)->currentMove)] << bonus; if (type_of(pos.piece_on(prevSq)) != PAWN && type_of((ss - 1)->currentMove) != PROMOTION) thisThread->pawnHistory[pawn_structure(pos)][pos.piece_on(prevSq)][prevSq] << bonus / 4; @@ -791,7 +765,7 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo // 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 - c1 - (c2 - c3 * ((ss + 1)->cutoffCnt > 3)) * depth * depth) + if (eval < alpha - 472 - (284 - 165 * ((ss + 1)->cutoffCnt > 3)) * depth * depth) { value = qsearch(pos, ss, alpha - 1, alpha); if (value < alpha) @@ -800,24 +774,24 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo // Step 8. Futility pruning: child node (~40 Elo) // The depth condition is important for mate finding. - if (!ss->ttPv && depth < c4 + if (!ss->ttPv && depth < 9 && eval - futility_margin(depth, cutNode && !ss->ttHit, improving) - - (ss - 1)->statScore / c5 + - (ss - 1)->statScore / 337 >= beta - && eval >= beta && eval < c6 // smaller than TB wins + && eval >= beta && eval < 29008 // smaller than TB wins && (!ttMove || ttCapture)) return (eval + beta) / 2; // Step 9. Null move search with verification search (~35 Elo) - if (!PvNode && (ss - 1)->currentMove != MOVE_NULL && (ss - 1)->statScore < c7 && eval >= beta - && eval >= ss->staticEval && ss->staticEval >= beta - c8 * depth + c9 && !excludedMove + if (!PvNode && (ss - 1)->currentMove != MOVE_NULL && (ss - 1)->statScore < 17496 && eval >= beta + && eval >= ss->staticEval && ss->staticEval >= beta - 23 * depth + 304 && !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) / c10, 6) + depth / 3 + 4; + Depth R = std::min(int(eval - beta) / 144, 6) + depth / 3 + 4; ss->currentMove = MOVE_NULL; ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0]; @@ -831,7 +805,7 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo // Do not return unproven mate or TB scores if (nullValue >= beta && nullValue < VALUE_TB_WIN_IN_MAX_PLY) { - if (thisThread->nmpMinPly || depth < c11) + if (thisThread->nmpMinPly || depth < 15) return nullValue; assert(!thisThread->nmpMinPly); // Recursive verification is not allowed @@ -861,10 +835,10 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo return qsearch(pos, ss, alpha, beta); // For cutNodes without a ttMove, we decrease depth by 2 if depth is high enough. - if (cutNode && depth >= c12 && !ttMove) + if (cutNode && depth >= 8 && !ttMove) depth -= 2; - probCutBeta = beta + c13 - c14 * improving; + probCutBeta = beta + 163 - 67 * improving; // Step 11. ProbCut (~10 Elo) // If we have a good enough capture (or queen promotion) and a reduced search returns a value @@ -922,7 +896,7 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo moves_loop: // When in check, search starts here // Step 12. A small Probcut idea, when we are in check (~4 Elo) - probCutBeta = beta + d1; + probCutBeta = beta + 425; if (ss->inCheck && !PvNode && ttCapture && (tte->bound() & BOUND_LOWER) && tte->depth() >= depth - 4 && ttValue >= probCutBeta && abs(ttValue) < VALUE_TB_WIN_IN_MAX_PLY && abs(beta) < VALUE_TB_WIN_IN_MAX_PLY) @@ -1005,18 +979,18 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo if (capture || givesCheck) { // Futility pruning for captures (~2 Elo) - if (!givesCheck && lmrDepth < d2 && !ss->inCheck) + if (!givesCheck && lmrDepth < 7 && !ss->inCheck) { Piece capturedPiece = pos.piece_on(to_sq(move)); int futilityEval = - ss->staticEval + d3 + d4 * lmrDepth + PieceValue[capturedPiece] + ss->staticEval + 238 + 305 * lmrDepth + PieceValue[capturedPiece] + captureHistory[movedPiece][to_sq(move)][type_of(capturedPiece)] / 7; if (futilityEval < alpha) continue; } // SEE based pruning for captures and checks (~11 Elo) - if (!pos.see_ge(move, Value(-d5) * depth)) + if (!pos.see_ge(move, Value(-187) * depth)) continue; } else @@ -1027,25 +1001,25 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo + thisThread->pawnHistory[pawn_structure(pos)][movedPiece][to_sq(move)]; // Continuation history based pruning (~2 Elo) - if (lmrDepth < d6 && history < -d7 * depth) + if (lmrDepth < 6 && history < -3752 * depth) continue; history += 2 * thisThread->mainHistory[us][from_to(move)]; - lmrDepth += history / d8; + lmrDepth += history / 7838; lmrDepth = std::max(lmrDepth, -1); // Futility pruning: parent node (~13 Elo) - if (!ss->inCheck && lmrDepth < d9 - && ss->staticEval + (bestValue < ss->staticEval - d10 ? d11 : d12) - + d13 * lmrDepth + if (!ss->inCheck && lmrDepth < 14 + && ss->staticEval + (bestValue < ss->staticEval - 57 ? 124 : 71) + + 118 * lmrDepth <= alpha) continue; lmrDepth = std::max(lmrDepth, 0); // Prune moves with negative SEE (~4 Elo) - if (!pos.see_ge(move, Value(-d14 * lmrDepth * lmrDepth))) + if (!pos.see_ge(move, Value(-26 * lmrDepth * lmrDepth))) continue; } } @@ -1065,11 +1039,11 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo // 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 > e1) + 2 * (PvNode && tte->is_pv()) + && depth >= 4 - (thisThread->completedDepth > 27) + 2 * (PvNode && tte->is_pv()) && abs(ttValue) < VALUE_TB_WIN_IN_MAX_PLY && (tte->bound() & BOUND_LOWER) && tte->depth() >= depth - 3) { - Value singularBeta = ttValue - (e2 + e3 * (ss->ttPv && !PvNode)) * depth / 64; + Value singularBeta = ttValue - (66 + 58 * (ss->ttPv && !PvNode)) * depth / 64; Depth singularDepth = newDepth / 2; ss->excludedMove = move; @@ -1083,10 +1057,10 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo singularQuietLMR = !ttCapture; // Avoid search explosion by limiting the number of double extensions - if (!PvNode && value < singularBeta - e4 && ss->doubleExtensions <= e5) + if (!PvNode && value < singularBeta - 17 && ss->doubleExtensions <= 11) { extension = 2; - depth += depth < e6; + depth += depth < 15; } } @@ -1110,7 +1084,7 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo // If we are on a cutNode but the ttMove is not assumed to fail high over current beta (~1 Elo) else if (cutNode) - extension = depth < e7 ? -2 : -1; + extension = depth < 19 ? -2 : -1; // If the ttMove is assumed to fail low over the value of the reduced search (~1 Elo) else if (ttValue <= value) @@ -1118,18 +1092,18 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo } // Check extensions (~1 Elo) - else if (givesCheck && depth > e8) + else if (givesCheck && depth > 10) extension = 1; // Quiet ttMove extensions (~1 Elo) else if (PvNode && move == ttMove && move == ss->killers[0] - && (*contHist[0])[movedPiece][to_sq(move)] >= e9) + && (*contHist[0])[movedPiece][to_sq(move)] >= 4325) extension = 1; // Recapture extensions (~1 Elo) else if (PvNode && move == ttMove && to_sq(move) == prevSq && captureHistory[movedPiece][to_sq(move)][type_of(pos.piece_on(to_sq(move)))] - > e10) + > 4146) extension = 1; } @@ -1153,7 +1127,7 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo r -= cutNode && tte->depth() >= depth ? 3 : 2; // Decrease reduction if opponent's move count is high (~1 Elo) - if ((ss - 1)->moveCount > e11) + if ((ss - 1)->moveCount > 7) r--; // Increase reduction for cut nodes (~3 Elo) @@ -1188,10 +1162,10 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo 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)] - e12; + + (*contHist[3])[movedPiece][to_sq(move)] - 3817; // Decrease/increase reduction for moves with a good/bad history (~25 Elo) - r -= ss->statScore / e13; + r -= ss->statScore / 14767; // Step 17. Late moves reduction / extension (LMR, ~117 Elo) // We use various heuristics for the sons of a node after the first son has @@ -1214,7 +1188,7 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo { // 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 + f1 + f2 * newDepth); // (~1 Elo) + const bool doDeeperSearch = value > (bestValue + 53 + 2 * newDepth); // (~1 Elo) const bool doShallowerSearch = value < bestValue + newDepth; // (~2 Elo) newDepth += doDeeperSearch - doShallowerSearch; @@ -1329,7 +1303,7 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo else { // Reduce other moves if we have found at least one score improvement (~2 Elo) - if (depth > f3 && depth < f4 && beta < f5 && value > -f6) + if (depth > 2 && depth < 12 && beta < 13782 && value > -11541) depth -= 2; assert(depth > 0); @@ -1368,8 +1342,8 @@ Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, boo // Bonus for prior countermove that caused the fail low else if (!priorCapture && prevSq != SQ_NONE) { - int bonus = (depth > f7) + (PvNode || cutNode) + (bestValue < alpha - f8) - + ((ss - 1)->moveCount > f9); + int bonus = (depth > 6) + (PvNode || cutNode) + (bestValue < alpha - 656) + + ((ss - 1)->moveCount > 10); update_continuation_histories(ss - 1, pos.piece_on(prevSq), prevSq, stat_bonus(depth) * bonus); thisThread->mainHistory[~us][from_to((ss - 1)->currentMove)] @@ -1501,7 +1475,7 @@ Value qsearch(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth) { if (bestValue > alpha) alpha = bestValue; - futilityBase = ss->staticEval + g1; + futilityBase = ss->staticEval + 182; } const PieceToHistory* contHist[] = {(ss - 1)->continuationHistory, @@ -1581,7 +1555,7 @@ Value qsearch(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth) { continue; // Do not search moves with bad enough SEE values (~5 Elo) - if (!pos.see_ge(move, Value(-g2))) + if (!pos.see_ge(move, Value(-77))) continue; } @@ -1717,7 +1691,7 @@ void update_all_stats(const Position& pos, if (!pos.capture_stage(bestMove)) { - int bestMoveBonus = bestValue > beta + g3 ? quietMoveBonus // larger bonus + int bestMoveBonus = bestValue > beta + 173 ? quietMoveBonus // larger bonus : stat_bonus(depth); // smaller bonus // Increase stats for the best move in case it was a quiet move @@ -1725,7 +1699,7 @@ void update_all_stats(const Position& pos, thisThread->pawnHistory[pawn_structure(pos)][moved_piece][to_sq(bestMove)] << quietMoveBonus; - int moveMalus = bestValue > beta + g4 ? quietMoveMalus // larger malus + int moveMalus = bestValue > beta + 165 ? quietMoveMalus // larger malus : stat_malus(depth); // smaller malus // Decrease stats for all non-best quiet moves