X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=da95877cf793f232a7b2f6c600fbb8895b612189;hp=0dccf934e82c2f823ed0f1b013589daf2ac6384a;hb=f2e78d9f841b53b8d512ad2687ff982cf841df58;hpb=13bc6ba2c69f326017dcc771d1e45a096e23e0c4 diff --git a/src/search.cpp b/src/search.cpp index 0dccf934..da95877c 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -20,7 +20,6 @@ #include #include #include -#include #include #include #include @@ -159,23 +158,19 @@ namespace { RootMoveList Rml; // MultiPV mode - int MultiPV, UCIMultiPV, MultiPVIteration; + int MultiPV, UCIMultiPV, MultiPVIdx; // Time management variables bool StopOnPonderhit, FirstRootMove, StopRequest, QuitRequest, AspirationFailLow; TimeManager TimeMgr; SearchLimits Limits; - // Log file - std::ofstream LogFile; - // Skill level adjustment int SkillLevel; bool SkillLevelEnabled; // Node counters, used only by thread[0] but try to keep in different cache // lines (64 bytes each) from the heavy multi-thread read accessed variables. - bool SendSearchedNodes; int NodesSincePoll; int NodesBetweenPolls = 30000; @@ -271,7 +266,7 @@ namespace { if (moveIsCheck && pos.see_sign(m) >= 0) result += CheckExtension[PvNode]; - if (piece_type(pos.piece_on(move_from(m))) == PAWN) + if (type_of(pos.piece_on(move_from(m))) == PAWN) { Color c = pos.side_to_move(); if (relative_rank(c, move_to(m)) == RANK_7) @@ -287,10 +282,10 @@ namespace { } if ( captureOrPromotion - && piece_type(pos.piece_on(move_to(m))) != PAWN + && type_of(pos.piece_on(move_to(m))) != PAWN && ( pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) - - piece_value_midgame(pos.piece_on(move_to(m))) == VALUE_ZERO) - && !move_is_special(m)) + - PieceValueMidgame[pos.piece_on(move_to(m))] == VALUE_ZERO) + && !is_special(m)) { result += PawnEndgameExtension[PvNode]; *dangerous = true; @@ -364,10 +359,10 @@ int64_t perft(Position& pos, Depth depth) { bool think(Position& pos, const SearchLimits& limits, Move searchMoves[]) { - static Book book; + static Book book; // Define static to initialize the PRNG only once // Initialize global search-related variables - StopOnPonderhit = StopRequest = QuitRequest = AspirationFailLow = SendSearchedNodes = false; + StopOnPonderhit = StopRequest = QuitRequest = AspirationFailLow = false; NodesSincePoll = 0; current_search_time(get_system_time()); Limits = limits; @@ -392,7 +387,7 @@ bool think(Position& pos, const SearchLimits& limits, Move searchMoves[]) { if (Options["Book File"].value() != book.name()) book.open(Options["Book File"].value()); - Move bookMove = book.get_move(pos, Options["Best Book Move"].value()); + Move bookMove = book.probe(pos, Options["Best Book Move"].value()); if (bookMove != MOVE_NONE) { if (Limits.ponder) @@ -410,8 +405,7 @@ bool think(Position& pos, const SearchLimits& limits, Move searchMoves[]) { read_evaluation_uci_options(pos.side_to_move()); Threads.read_uci_options(); - // If needed allocate pawn and material hash tables and adjust TT size - Threads.init_hash_tables(); + // Set a new TT size if changed TT.set_size(Options["Hash"].value()); if (Options["Clear Hash"].value()) @@ -435,17 +429,14 @@ bool think(Position& pos, const SearchLimits& limits, Move searchMoves[]) { // Write to log file and keep it open to be accessed during the search if (Options["Use Search Log"].value()) { - string name = Options["Search Log Filename"].value(); - LogFile.open(name.c_str(), std::ios::out | std::ios::app); - - if (LogFile.is_open()) - LogFile << "\nSearching: " << pos.to_fen() - << "\ninfinite: " << Limits.infinite - << " ponder: " << Limits.ponder - << " time: " << Limits.time - << " increment: " << Limits.increment - << " moves to go: " << Limits.movesToGo - << endl; + Log log(Options["Search Log Filename"].value()); + log << "\nSearching: " << pos.to_fen() + << "\ninfinite: " << Limits.infinite + << " ponder: " << Limits.ponder + << " time: " << Limits.time + << " increment: " << Limits.increment + << " moves to go: " << Limits.movesToGo + << endl; } // We're ready to start thinking. Call the iterative deepening loop function @@ -453,19 +444,19 @@ bool think(Position& pos, const SearchLimits& limits, Move searchMoves[]) { Move bestMove = id_loop(pos, searchMoves, &ponderMove); // Write final search statistics and close log file - if (LogFile.is_open()) + if (Options["Use Search Log"].value()) { int t = current_search_time(); - LogFile << "Nodes: " << pos.nodes_searched() - << "\nNodes/second: " << (t > 0 ? pos.nodes_searched() * 1000 / t : 0) - << "\nBest move: " << move_to_san(pos, bestMove); + Log log(Options["Search Log Filename"].value()); + log << "Nodes: " << pos.nodes_searched() + << "\nNodes/second: " << (t > 0 ? pos.nodes_searched() * 1000 / t : 0) + << "\nBest move: " << move_to_san(pos, bestMove); StateInfo st; pos.do_move(bestMove, st); - LogFile << "\nPonder move: " << move_to_san(pos, ponderMove) << endl; + log << "\nPonder move: " << move_to_san(pos, ponderMove) << endl; pos.undo_move(bestMove); // Return from think() with unchanged position - LogFile.close(); } // This makes all the threads to go to sleep @@ -529,18 +520,17 @@ namespace { // Iterative deepening loop until requested to stop or target depth reached while (!StopRequest && ++depth <= PLY_MAX && (!Limits.maxDepth || depth <= Limits.maxDepth)) { - // Save last iteration's scores, this needs to be done now, because in - // the following MultiPV loop Rml moves could be reordered. + // Save now last iteration's scores, before Rml moves are reordered for (size_t i = 0; i < Rml.size(); i++) Rml[i].prevScore = Rml[i].score; Rml.bestMoveChanges = 0; - // MultiPV iteration loop - for (MultiPVIteration = 0; MultiPVIteration < Min(MultiPV, (int)Rml.size()); MultiPVIteration++) + // MultiPV loop. We perform a full root search for each PV line + for (MultiPVIdx = 0; MultiPVIdx < Min(MultiPV, (int)Rml.size()); MultiPVIdx++) { // Calculate dynamic aspiration window based on previous iterations - if (depth >= 5 && abs(Rml[MultiPVIteration].prevScore) < VALUE_KNOWN_WIN) + if (depth >= 5 && abs(Rml[MultiPVIdx].prevScore) < VALUE_KNOWN_WIN) { int prevDelta1 = bestValues[depth - 1] - bestValues[depth - 2]; int prevDelta2 = bestValues[depth - 2] - bestValues[depth - 3]; @@ -548,8 +538,8 @@ namespace { aspirationDelta = Min(Max(abs(prevDelta1) + abs(prevDelta2) / 2, 16), 24); aspirationDelta = (aspirationDelta + 7) / 8 * 8; // Round to match grainSize - alpha = Max(Rml[MultiPVIteration].prevScore - aspirationDelta, -VALUE_INFINITE); - beta = Min(Rml[MultiPVIteration].prevScore + aspirationDelta, VALUE_INFINITE); + alpha = Max(Rml[MultiPVIdx].prevScore - aspirationDelta, -VALUE_INFINITE); + beta = Min(Rml[MultiPVIdx].prevScore + aspirationDelta, VALUE_INFINITE); } else { @@ -560,44 +550,61 @@ namespace { // Start with a small aspiration window and, in case of fail high/low, // research with bigger window until not failing high/low anymore. do { - // Search starting from ss+1 to allow calling update_gains() + // Search starts from ss+1 to allow referencing (ss-1). This is + // needed by update_gains() and ss copy when splitting at Root. value = search(pos, ss+1, alpha, beta, depth * ONE_PLY); - // It is critical that sorting is done with a stable algorithm - // because all the values but the first are usually set to - // -VALUE_INFINITE and we want to keep the same order for all - // the moves but the new PV that goes to head. - sort(Rml.begin() + MultiPVIteration, Rml.end()); - - // In case we have found an exact score reorder the PV moves - // before leaving the fail high/low loop, otherwise leave the - // last PV move in its position so to be searched again. - if (value > alpha && value < beta) - sort(Rml.begin(), Rml.begin() + MultiPVIteration); + // Bring to front the best move. It is critical that sorting is + // done with a stable algorithm because all the values but the first + // and eventually the new best one are set to -VALUE_INFINITE and + // we want to keep the same order for all the moves but the new + // PV that goes to the front. Note that in case of MultiPV search + // the already searched PV lines are preserved. + sort(Rml.begin() + MultiPVIdx, Rml.end()); + + // In case we have found an exact score and we are going to leave + // the fail high/low loop then reorder the PV moves, otherwise + // leave the last PV move in its position so to be searched again. + // Of course this is needed only in MultiPV search. + if (MultiPVIdx && value > alpha && value < beta) + sort(Rml.begin(), Rml.begin() + MultiPVIdx); // Write PV back to transposition table in case the relevant entries // have been overwritten during the search. - for (int i = 0; i <= MultiPVIteration; i++) + for (int i = 0; i <= MultiPVIdx; i++) Rml[i].insert_pv_in_tt(pos); - // Value cannot be trusted. Break out immediately! + // If search has been stopped exit the aspiration window loop, + // note that sorting and writing PV back to TT is safe becuase + // Rml is still valid, although refers to the previous iteration. if (StopRequest) break; // Send full PV info to GUI if we are going to leave the loop or - // if we have a fail high/low and we are deep in the search. + // if we have a fail high/low and we are deep in the search. UCI + // protocol requires to send all the PV lines also if are still + // to be searched and so refer to the previous search's score. if ((value > alpha && value < beta) || current_search_time() > 2000) - for (int i = 0; i < Min(UCIMultiPV, MultiPVIteration + 1); i++) + for (int i = 0; i < Min(UCIMultiPV, (int)Rml.size()); i++) + { + bool updated = (i <= MultiPVIdx); + + if (depth == 1 && !updated) + continue; + + Depth d = (updated ? depth : depth - 1) * ONE_PLY; + Value s = (updated ? Rml[i].score : Rml[i].prevScore); + cout << "info" - << depth_to_uci(depth * ONE_PLY) - << (i == MultiPVIteration ? score_to_uci(Rml[i].score, alpha, beta) : - score_to_uci(Rml[i].score)) + << depth_to_uci(d) + << (i == MultiPVIdx ? score_to_uci(s, alpha, beta) : score_to_uci(s)) << speed_to_uci(pos.nodes_searched()) << pv_to_uci(&Rml[i].pv[0], i + 1, pos.is_chess960()) << endl; + } - // In case of failing high/low increase aspiration window and research, - // otherwise exit the fail high/low loop. + // In case of failing high/low increase aspiration window and + // research, otherwise exit the fail high/low loop. if (value >= beta) { beta = Min(beta + aspirationDelta, VALUE_INFINITE); @@ -623,14 +630,17 @@ namespace { bestValues[depth] = value; bestMoveChanges[depth] = Rml.bestMoveChanges; - // Do we need to pick now the best and the ponder moves ? + // Skills: Do we need to pick now the best and the ponder moves ? if (SkillLevelEnabled && depth == 1 + SkillLevel) do_skill_level(&skillBest, &skillPonder); - if (LogFile.is_open()) - LogFile << pretty_pv(pos, depth, value, current_search_time(), &Rml[0].pv[0]) << endl; + if (Options["Use Search Log"].value()) + { + Log log(Options["Search Log Filename"].value()); + log << pretty_pv(pos, depth, value, current_search_time(), &Rml[0].pv[0]) << endl; + } - // Init easyMove after first iteration or drop if differs from the best move + // Init easyMove at first iteration or drop it if differs from the best move if (depth == 1 && (Rml.size() == 1 || Rml[0].score > Rml[1].score + EasyMoveMargin)) easyMove = bestMove; else if (bestMove != easyMove) @@ -639,9 +649,9 @@ namespace { // Check for some early stop condition if (!StopRequest && Limits.useTimeManagement()) { - // Stop search early if one move seems to be much better than the - // others or if there is only a single legal move. Also in the latter - // case we search up to some depth anyway to get a proper score. + // Easy move: Stop search early if one move seems to be much better + // than the others or if there is only a single legal move. Also in + // the latter case search to some depth anyway to get a proper score. if ( depth >= 7 && easyMove == bestMove && ( Rml.size() == 1 @@ -711,7 +721,7 @@ namespace { Depth ext, newDepth; ValueType vt; Value bestValue, value, oldAlpha; - Value refinedValue, nullValue, futilityBase, futilityValueScaled; // Non-PV specific + Value refinedValue, nullValue, futilityBase, futilityValue; bool isPvMove, inCheck, singularExtensionNode, givesCheck, captureOrPromotion, dangerous; int moveCount = 0, playedMoveCount = 0; Thread& thread = Threads[pos.thread()]; @@ -769,7 +779,7 @@ namespace { excludedMove = ss->excludedMove; posKey = excludedMove ? pos.get_exclusion_key() : pos.get_key(); tte = TT.probe(posKey); - ttMove = RootNode ? Rml[MultiPVIteration].pv[0] : tte ? tte->move() : MOVE_NONE; + ttMove = RootNode ? Rml[MultiPVIdx].pv[0] : tte ? tte->move() : MOVE_NONE; // At PV nodes we check for exact scores, while at non-PV nodes we check for // a fail high/low. Biggest advantage at probing at PV nodes is to have a @@ -779,8 +789,18 @@ namespace { : can_return_tt(tte, depth, beta, ss->ply))) { TT.refresh(tte); - ss->bestMove = ttMove; // Can be MOVE_NONE - return value_from_tt(tte->value(), ss->ply); + ss->bestMove = move = ttMove; // Can be MOVE_NONE + value = value_from_tt(tte->value(), ss->ply); + + if ( value >= beta + && move + && !pos.is_capture_or_promotion(move) + && move != ss->killers[0]) + { + ss->killers[1] = ss->killers[0]; + ss->killers[0] = move; + } + return value; } // Step 5. Evaluate the position statically and update parent's gain statistics @@ -963,15 +983,15 @@ split_point_start: // At split points actual search starts from here && (move = mp.get_next_move()) != MOVE_NONE && !thread.cutoff_occurred()) { - assert(move_is_ok(move)); + assert(is_ok(move)); if (move == excludedMove) continue; - // At root obey the "searchmoves" option and skip moves not listed in Root Move List. - // Also in MultiPV mode we skip moves which already have got an exact score - // in previous MultiPV Iteration. Finally any illegal move is skipped here. - if (RootNode && !Rml.find(move, MultiPVIteration)) + // At root obey the "searchmoves" option and skip moves not listed in Root + // Move List, as a consequence any illegal move is also skipped. In MultiPV + // mode we also skip PV moves which have been already searched. + if (RootNode && !Rml.find(move, MultiPVIdx)) continue; // At PV and SpNode nodes we want all moves to be legal since the beginning @@ -994,25 +1014,17 @@ split_point_start: // At split points actual search starts from here // Save the current node count before the move is searched nodes = pos.nodes_searched(); - // If it's time to send nodes info, do it here where we have the - // correct accumulated node counts searched by each thread. - if (!SpNode && SendSearchedNodes) - { - SendSearchedNodes = false; - cout << "info" << speed_to_uci(pos.nodes_searched()) << endl; - } - // For long searches send current move info to GUI if (pos.thread() == 0 && current_search_time() > 2000) cout << "info" << depth_to_uci(depth) << " currmove " << move - << " currmovenumber " << moveCount + MultiPVIteration << endl; + << " currmovenumber " << moveCount + MultiPVIdx << endl; } // At Root and at first iteration do a PV search on all the moves to score root moves isPvMove = (PvNode && moveCount <= (RootNode && depth <= ONE_PLY ? MAX_MOVES : 1)); givesCheck = pos.move_gives_check(move, ci); - captureOrPromotion = pos.move_is_capture_or_promotion(move); + captureOrPromotion = pos.is_capture_or_promotion(move); // Step 12. Decide the new search depth ext = extension(pos, move, captureOrPromotion, givesCheck, &dangerous); @@ -1052,7 +1064,7 @@ split_point_start: // At split points actual search starts from here && !inCheck && !dangerous && move != ttMove - && !move_is_castle(move)) + && !is_castle(move)) { // Move count based pruning if ( moveCount >= futility_move_count(depth) @@ -1069,19 +1081,19 @@ split_point_start: // At split points actual search starts from here // We illogically ignore reduction condition depth >= 3*ONE_PLY for predicted depth, // but fixing this made program slightly weaker. Depth predictedDepth = newDepth - reduction(depth, moveCount); - futilityValueScaled = futilityBase + futility_margin(predictedDepth, moveCount) - + H.gain(pos.piece_on(move_from(move)), move_to(move)); + futilityValue = futilityBase + futility_margin(predictedDepth, moveCount) + + H.gain(pos.piece_on(move_from(move)), move_to(move)); - if (futilityValueScaled < beta) + if (futilityValue < beta) { if (SpNode) { lock_grab(&(sp->lock)); - if (futilityValueScaled > sp->bestValue) - sp->bestValue = bestValue = futilityValueScaled; + if (futilityValue > sp->bestValue) + sp->bestValue = bestValue = futilityValue; } - else if (futilityValueScaled > bestValue) - bestValue = futilityValueScaled; + else if (futilityValue > bestValue) + bestValue = futilityValue; continue; } @@ -1126,7 +1138,7 @@ split_point_start: // At split points actual search starts from here if ( depth > 3 * ONE_PLY && !captureOrPromotion && !dangerous - && !move_is_castle(move) + && !is_castle(move) && ss->killers[0] != move && ss->killers[1] != move && (ss->reduction = reduction(depth, moveCount)) != DEPTH_ZERO) @@ -1170,17 +1182,12 @@ split_point_start: // At split points actual search starts from here alpha = sp->alpha; } - - if (RootNode) + // Finished searching the move. If StopRequest is true, the search + // was aborted because the user interrupted the search or because we + // ran out of time. In this case, the return value of the search cannot + // be trusted, and we don't update the best move and/or PV. + if (RootNode && !StopRequest) { - // Finished searching the move. If StopRequest is true, the search - // was aborted because the user interrupted the search or because we - // ran out of time. In this case, the return value of the search cannot - // be trusted, and we break out of the loop without updating the best - // move and/or PV. - if (StopRequest) - break; - // Remember searched nodes counts for this move RootMove* rm = Rml.find(move); rm->nodes += pos.nodes_searched() - nodes; @@ -1226,21 +1233,22 @@ split_point_start: // At split points actual search starts from here } // Step 19. Check for split - if ( !RootNode - && !SpNode + if ( !SpNode && depth >= Threads.min_split_depth() && bestValue < beta && Threads.available_slave_exists(pos.thread()) && !StopRequest && !thread.cutoff_occurred()) - Threads.split(pos, ss, &alpha, beta, &bestValue, depth, - threatMove, moveCount, &mp, PvNode); + bestValue = Threads.split(pos, ss, alpha, beta, bestValue, depth, + threatMove, moveCount, &mp, NT); } // Step 20. Check for mate and stalemate - // All legal moves have been searched and if there are - // no legal moves, it must be mate or stalemate. - // If one move was excluded return fail low score. + // All legal moves have been searched and if there are no legal moves, it + // must be mate or stalemate. Note that we can have a false positive in + // case of StopRequest or thread.cutoff_occurred() are set, but this is + // harmless because return value is discarded anyhow in the parent nodes. + // If we are in a singular extension search then return a fail low score. if (!SpNode && !moveCount) return excludedMove ? oldAlpha : inCheck ? value_mated_in(ss->ply) : VALUE_DRAW; @@ -1257,7 +1265,7 @@ split_point_start: // At split points actual search starts from here // Update killers and history only for non capture moves that fails high if ( bestValue >= beta - && !pos.move_is_capture_or_promotion(move)) + && !pos.is_capture_or_promotion(move)) { if (move != ss->killers[0]) { @@ -1303,6 +1311,7 @@ split_point_start: // At split points actual search starts from here bool inCheck, enoughMaterial, givesCheck, evasionPrunable; const TTEntry* tte; Depth ttDepth; + ValueType vt; Value oldAlpha = alpha; ss->bestMove = ss->currentMove = MOVE_NONE; @@ -1373,10 +1382,10 @@ split_point_start: // At split points actual search starts from here CheckInfo ci(pos); // Loop through the moves until no moves remain or a beta cutoff occurs - while ( alpha < beta + while ( bestValue < beta && (move = mp.get_next_move()) != MOVE_NONE) { - assert(move_is_ok(move)); + assert(is_ok(move)); givesCheck = pos.move_gives_check(move, ci); @@ -1386,17 +1395,18 @@ split_point_start: // At split points actual search starts from here && !givesCheck && move != ttMove && enoughMaterial - && !move_is_promotion(move) - && !pos.move_is_passed_pawn_push(move)) + && !is_promotion(move) + && !pos.is_passed_pawn_push(move)) { futilityValue = futilityBase - + piece_value_endgame(pos.piece_on(move_to(move))) - + (move_is_ep(move) ? PawnValueEndgame : VALUE_ZERO); + + PieceValueEndgame[pos.piece_on(move_to(move))] + + (is_enpassant(move) ? PawnValueEndgame : VALUE_ZERO); - if (futilityValue < alpha) + if (futilityValue < beta) { if (futilityValue > bestValue) bestValue = futilityValue; + continue; } @@ -1411,14 +1421,14 @@ split_point_start: // At split points actual search starts from here evasionPrunable = !PvNode && inCheck && bestValue > VALUE_MATED_IN_PLY_MAX - && !pos.move_is_capture(move) + && !pos.is_capture(move) && !pos.can_castle(pos.side_to_move()); // Don't search moves with negative SEE values if ( !PvNode && (!inCheck || evasionPrunable) && move != ttMove - && !move_is_promotion(move) + && !is_promotion(move) && pos.see_sign(move) < 0) continue; @@ -1427,7 +1437,7 @@ split_point_start: // At split points actual search starts from here && !inCheck && givesCheck && move != ttMove - && !pos.move_is_capture_or_promotion(move) + && !pos.is_capture_or_promotion(move) && ss->eval + PawnValueMidgame / 4 < beta && !check_is_dangerous(pos, move, futilityBase, beta, &bestValue)) { @@ -1455,11 +1465,12 @@ split_point_start: // At split points actual search starts from here if (value > bestValue) { bestValue = value; - if (value > alpha) - { + ss->bestMove = move; + + if ( PvNode + && value > alpha + && value < beta) // We want always alpha < beta alpha = value; - ss->bestMove = move; - } } } @@ -1469,8 +1480,11 @@ split_point_start: // At split points actual search starts from here return value_mated_in(ss->ply); // Update transposition table - ValueType vt = (bestValue <= oldAlpha ? VALUE_TYPE_UPPER : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT); - TT.store(pos.get_key(), value_to_tt(bestValue, ss->ply), vt, ttDepth, ss->bestMove, ss->eval, evalMargin); + move = bestValue <= oldAlpha ? MOVE_NONE : ss->bestMove; + vt = bestValue <= oldAlpha ? VALUE_TYPE_UPPER + : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT; + + TT.store(pos.get_key(), value_to_tt(bestValue, ss->ply), vt, ttDepth, move, ss->eval, evalMargin); assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE); @@ -1492,7 +1506,7 @@ split_point_start: // At split points actual search starts from here from = move_from(move); to = move_to(move); - them = opposite_color(pos.side_to_move()); + them = flip(pos.side_to_move()); ksq = pos.king_square(them); kingAtt = pos.attacks_from(ksq); pc = pos.piece_on(from); @@ -1508,7 +1522,7 @@ split_point_start: // At split points actual search starts from here return true; // Rule 2. Queen contact check is very dangerous - if ( piece_type(pc) == QUEEN + if ( type_of(pc) == QUEEN && bit_is_set(kingAtt, to)) return true; @@ -1518,7 +1532,7 @@ split_point_start: // At split points actual search starts from here while (b) { victimSq = pop_1st_bit(&b); - futilityValue = futilityBase + piece_value_endgame(pos.piece_on(victimSq)); + futilityValue = futilityBase + PieceValueEndgame[pos.piece_on(victimSq)]; // Note that here we generate illegal "double move"! if ( futilityValue >= beta @@ -1547,8 +1561,8 @@ split_point_start: // At split points actual search starts from here Piece p1, p2; Square ksq; - assert(m1 && move_is_ok(m1)); - assert(m2 && move_is_ok(m2)); + assert(is_ok(m1)); + assert(is_ok(m2)); // Case 1: The moving piece is the same in both moves f2 = move_from(m2); @@ -1623,10 +1637,10 @@ split_point_start: // At split points actual search starts from here bool connected_threat(const Position& pos, Move m, Move threat) { - assert(move_is_ok(m)); - assert(threat && move_is_ok(threat)); - assert(!pos.move_is_capture_or_promotion(m)); - assert(!pos.move_is_passed_pawn_push(m)); + assert(is_ok(m)); + assert(is_ok(threat)); + assert(!pos.is_capture_or_promotion(m)); + assert(!pos.is_passed_pawn_push(m)); Square mfrom, mto, tfrom, tto; @@ -1641,9 +1655,9 @@ split_point_start: // At split points actual search starts from here // Case 2: If the threatened piece has value less than or equal to the // value of the threatening piece, don't prune moves which defend it. - if ( pos.move_is_capture(threat) - && ( piece_value_midgame(pos.piece_on(tfrom)) >= piece_value_midgame(pos.piece_on(tto)) - || piece_type(pos.piece_on(tfrom)) == KING) + if ( pos.is_capture(threat) + && ( PieceValueMidgame[pos.piece_on(tfrom)] >= PieceValueMidgame[pos.piece_on(tto)] + || type_of(pos.piece_on(tfrom)) == KING) && pos.move_attacks_square(m, tto)) return true; @@ -1721,7 +1735,7 @@ split_point_start: // At split points actual search starts from here && before != VALUE_NONE && after != VALUE_NONE && pos.captured_piece_type() == PIECE_TYPE_NONE - && !move_is_special(m)) + && !is_special(m)) H.update_gain(pos.piece_on(move_to(m)), move_to(m), -(before + after)); } @@ -1950,9 +1964,6 @@ split_point_start: // At split points actual search starts from here dbg_print_mean(); dbg_print_hit_rate(); - - // Send info on searched nodes as soon as we return to root - SendSearchedNodes = true; } // Should we stop the search? @@ -2085,7 +2096,7 @@ split_point_start: // At split points actual search starts from here int ply = 1; Move m = pv[0]; - assert(m != MOVE_NONE && pos.move_is_pl(m)); + assert(m != MOVE_NONE && pos.is_pseudo_legal(m)); pv.clear(); pv.push_back(m); @@ -2093,7 +2104,7 @@ split_point_start: // At split points actual search starts from here while ( (tte = TT.probe(pos.get_key())) != NULL && tte->move() != MOVE_NONE - && pos.move_is_pl(tte->move()) + && pos.is_pseudo_legal(tte->move()) && pos.pl_move_is_legal(tte->move(), pos.pinned_pieces()) && ply < PLY_MAX && (!pos.is_draw() || ply < 2)) @@ -2119,7 +2130,7 @@ split_point_start: // At split points actual search starts from here Value v, m = VALUE_NONE; int ply = 0; - assert(pv[0] != MOVE_NONE && pos.move_is_pl(pv[0])); + assert(pv[0] != MOVE_NONE && pos.is_pseudo_legal(pv[0])); do { k = pos.get_key(); @@ -2140,110 +2151,104 @@ split_point_start: // At split points actual search starts from here } // namespace -// ThreadsManager::idle_loop() is where the threads are parked when they have no work -// to do. The parameter 'sp', if non-NULL, is a pointer to an active SplitPoint -// object for which the current thread is the master. +// Little helper used by idle_loop() to check that all the slave threads of a +// split point have finished searching. -void ThreadsManager::idle_loop(int threadID, SplitPoint* sp) { +static bool all_slaves_finished(SplitPoint* sp) { - assert(threadID >= 0 && threadID < MAX_THREADS); + for (int i = 0; i < Threads.size(); i++) + if (sp->is_slave[i]) + return false; + + return true; +} - int i; - bool allFinished; + +// Thread::idle_loop() is where the thread is parked when it has no work to do. +// The parameter 'sp', if non-NULL, is a pointer to an active SplitPoint object +// for which the thread is the master. + +void Thread::idle_loop(SplitPoint* sp) { while (true) { - // Slave threads can exit as soon as AllThreadsShouldExit raises, - // master should exit as last one. - if (allThreadsShouldExit) - { - assert(!sp); - threads[threadID].state = Thread::TERMINATED; - return; - } - - // If we are not thinking, wait for a condition to be signaled + // If we are not searching, wait for a condition to be signaled // instead of wasting CPU time polling for work. - while ( threadID >= activeThreads - || threads[threadID].state == Thread::INITIALIZING - || (useSleepingThreads && threads[threadID].state == Thread::AVAILABLE)) + while ( do_sleep + || do_terminate + || (Threads.use_sleeping_threads() && !is_searching)) { - assert(!sp || useSleepingThreads); - assert(threadID != 0 || useSleepingThreads); + assert((!sp && threadID) || Threads.use_sleeping_threads()); - if (threads[threadID].state == Thread::INITIALIZING) - threads[threadID].state = Thread::AVAILABLE; + // Slave thread should exit as soon as do_terminate flag raises + if (do_terminate) + { + assert(!sp); + return; + } // Grab the lock to avoid races with Thread::wake_up() - lock_grab(&threads[threadID].sleepLock); - - // If we are master and all slaves have finished do not go to sleep - for (i = 0; sp && i < activeThreads && !sp->is_slave[i]; i++) {} - allFinished = (i == activeThreads); + lock_grab(&sleepLock); - if (allFinished || allThreadsShouldExit) + // If we are master and all slaves have finished don't go to sleep + if (sp && all_slaves_finished(sp)) { - lock_release(&threads[threadID].sleepLock); + lock_release(&sleepLock); break; } - // Do sleep here after retesting sleep conditions - if (threadID >= activeThreads || threads[threadID].state == Thread::AVAILABLE) - cond_wait(&threads[threadID].sleepCond, &threads[threadID].sleepLock); + // Do sleep after retesting sleep conditions under lock protection, in + // particular we need to avoid a deadlock in case a master thread has, + // in the meanwhile, allocated us and sent the wake_up() call before we + // had the chance to grab the lock. + if (do_sleep || !is_searching) + cond_wait(&sleepCond, &sleepLock); - lock_release(&threads[threadID].sleepLock); + lock_release(&sleepLock); } // If this thread has been assigned work, launch a search - if (threads[threadID].state == Thread::WORKISWAITING) + if (is_searching) { - assert(!allThreadsShouldExit); - - threads[threadID].state = Thread::SEARCHING; + assert(!do_terminate); // Copy split point position and search stack and call search() - // with SplitPoint template parameter set to true. SearchStack ss[PLY_MAX_PLUS_2]; - SplitPoint* tsp = threads[threadID].splitPoint; + SplitPoint* tsp = splitPoint; Position pos(*tsp->pos, threadID); memcpy(ss, tsp->ss - 1, 4 * sizeof(SearchStack)); (ss+1)->sp = tsp; - if (tsp->pvNode) + if (tsp->nodeType == Root) + search(pos, ss+1, tsp->alpha, tsp->beta, tsp->depth); + else if (tsp->nodeType == PV) search(pos, ss+1, tsp->alpha, tsp->beta, tsp->depth); - else + else if (tsp->nodeType == NonPV) search(pos, ss+1, tsp->alpha, tsp->beta, tsp->depth); + else + assert(false); - assert(threads[threadID].state == Thread::SEARCHING); + assert(is_searching); - threads[threadID].state = Thread::AVAILABLE; + is_searching = false; // Wake up master thread so to allow it to return from the idle loop in // case we are the last slave of the split point. - if ( useSleepingThreads + if ( Threads.use_sleeping_threads() && threadID != tsp->master - && threads[tsp->master].state == Thread::AVAILABLE) - threads[tsp->master].wake_up(); + && !Threads[tsp->master].is_searching) + Threads[tsp->master].wake_up(); } // If this thread is the master of a split point and all slaves have // finished their work at this split point, return from the idle loop. - for (i = 0; sp && i < activeThreads && !sp->is_slave[i]; i++) {} - allFinished = (i == activeThreads); - - if (allFinished) + if (sp && all_slaves_finished(sp)) { - // Because sp->slaves[] is reset under lock protection, + // Because sp->is_slave[] is reset under lock protection, // be sure sp->lock has been released before to return. lock_grab(&(sp->lock)); lock_release(&(sp->lock)); - - // In helpful master concept a master can help only a sub-tree, and - // because here is all finished is not possible master is booked. - assert(threads[threadID].state == Thread::AVAILABLE); - - threads[threadID].state = Thread::SEARCHING; return; } }