X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=5921ae0fd77a093c95b59e3c0c8f3a1b2d02bc04;hp=cd8a9e461083a63fd21531fb88cf6944f67db09b;hb=c71ae794df257e3d6f1e925b6d013434bb2f99ef;hpb=808a4fe817f79f472c92e7b9fb914a8be73ff1be diff --git a/src/search.cpp b/src/search.cpp index cd8a9e46..5921ae0f 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -40,6 +41,7 @@ using std::cout; using std::endl; +using std::string; namespace { @@ -50,86 +52,33 @@ namespace { enum NodeType { Root, PV, NonPV, SplitPointPV, SplitPointNonPV }; // RootMove struct is used for moves at the root of the tree. For each root - // move, we store two scores, a node count, and a PV (really a refutation + // move, we store a pv_score, a node count, and a PV (really a refutation // in the case of moves which fail low). Value pv_score is normally set at - // -VALUE_INFINITE for all non-pv moves, while non_pv_score is computed - // according to the order in which moves are returned by MovePicker. + // -VALUE_INFINITE for all non-pv moves. struct RootMove { - RootMove(); - RootMove(const RootMove& rm) { *this = rm; } - RootMove& operator=(const RootMove& rm); - // RootMove::operator<() is the comparison function used when // sorting the moves. A move m1 is considered to be better - // than a move m2 if it has an higher pv_score, or if it has - // equal pv_score but m1 has the higher non_pv_score. In this way - // we are guaranteed that PV moves are always sorted as first. - bool operator<(const RootMove& m) const { - return pv_score != m.pv_score ? pv_score < m.pv_score - : non_pv_score < m.non_pv_score; - } + // than a move m2 if it has an higher pv_score + bool operator<(const RootMove& m) const { return pv_score < m.pv_score; } void extract_pv_from_tt(Position& pos); void insert_pv_in_tt(Position& pos); - std::string pv_info_to_uci(Position& pos, int depth, int selDepth, - Value alpha, Value beta, int pvIdx); + int64_t nodes; Value pv_score; - Value non_pv_score; - Move pv[PLY_MAX_PLUS_2]; + std::vector pv; }; - // RootMoveList struct is just a vector of RootMove objects, - // with an handful of methods above the standard ones. + // RootMoveList struct is mainly a std::vector of RootMove objects struct RootMoveList : public std::vector { - typedef std::vector Base; - void init(Position& pos, Move searchMoves[]); - void sort() { insertion_sort(begin(), end()); } - void sort_multipv(int n) { insertion_sort(begin(), begin() + n); } + RootMove* find(const Move& m, int startIndex = 0); int bestMoveChanges; }; - // MovePickerExt template class extends MovePicker and allows to choose at compile - // time the proper moves source according to the type of node. In the default case - // we simply create and use a standard MovePicker object. - template struct MovePickerExt : public MovePicker { - - MovePickerExt(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value b) - : MovePicker(p, ttm, d, h, ss, b) {} - - RootMoveList::iterator rm; // Dummy, needed to compile - }; - - // In case of a SpNode we use split point's shared MovePicker object as moves source - template<> struct MovePickerExt : public MovePickerExt { - - MovePickerExt(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value b) - : MovePickerExt(p, ttm, d, h, ss, b), mp(ss->sp->mp) {} - - Move get_next_move() { return mp->get_next_move(); } - MovePicker* mp; - }; - - template<> struct MovePickerExt : public MovePickerExt { - - MovePickerExt(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value b) - : MovePickerExt(p, ttm, d, h, ss, b) {} - }; - - // In case of a Root node we use RootMoveList as moves source - template<> struct MovePickerExt : public MovePicker { - - MovePickerExt(const Position&, Move, Depth, const History&, SearchStack*, Value); - Move get_next_move(); - - RootMoveList::iterator rm; - bool firstCall; - }; - /// Constants @@ -209,7 +158,7 @@ namespace { RootMoveList Rml; // MultiPV mode - int MultiPV, UCIMultiPV; + int MultiPV, UCIMultiPV, MultiPVIteration; // Time management variables bool StopOnPonderhit, FirstRootMove, StopRequest, QuitRequest, AspirationFailLow; @@ -255,11 +204,39 @@ namespace { void do_skill_level(Move* best, Move* ponder); int current_search_time(int set = 0); - std::string value_to_uci(Value v); - std::string speed_to_uci(int64_t nodes); + string score_to_uci(Value v, Value alpha = -VALUE_INFINITE, Value beta = VALUE_INFINITE); + string speed_to_uci(int64_t nodes); + string pv_to_uci(const Move pv[], int pvNum, bool chess960); + string pretty_pv(Position& pos, int depth, Value score, int time, Move pv[]); + string depth_to_uci(Depth depth); void poll(const Position& pos); void wait_for_stop_or_ponderhit(); + // MovePickerExt template class extends MovePicker and allows to choose at compile + // time the proper moves source according to the type of node. In the default case + // we simply create and use a standard MovePicker object. + template struct MovePickerExt : public MovePicker { + + MovePickerExt(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value b) + : MovePicker(p, ttm, d, h, ss, b) {} + }; + + // In case of a SpNode we use split point's shared MovePicker object as moves source + template<> struct MovePickerExt : public MovePicker { + + MovePickerExt(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value b) + : MovePicker(p, ttm, d, h, ss, b), mp(ss->sp->mp) {} + + Move get_next_move() { return mp->get_next_move(); } + MovePicker* mp; + }; + + template<> struct MovePickerExt : public MovePickerExt { + + MovePickerExt(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value b) + : MovePickerExt(p, ttm, d, h, ss, b) {} + }; + // Overload operator<<() to make it easier to print moves in a coordinate // notation compatible with UCI protocol. std::ostream& operator<<(std::ostream& os, Move m) { @@ -299,7 +276,7 @@ namespace { if (moveIsCheck && pos.see_sign(m) >= 0) result += CheckExtension[PvNode]; - if (pos.type_of_piece_on(move_from(m)) == PAWN) + if (piece_type(pos.piece_on(move_from(m))) == PAWN) { Color c = pos.side_to_move(); if (relative_rank(c, move_to(m)) == RANK_7) @@ -315,9 +292,9 @@ namespace { } if ( captureOrPromotion - && pos.type_of_piece_on(move_to(m)) != PAWN + && piece_type(pos.piece_on(move_to(m))) != PAWN && ( pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) - - pos.midgame_value_of_piece_on(move_to(m)) == VALUE_ZERO) + - piece_value_midgame(pos.piece_on(move_to(m))) == VALUE_ZERO) && !move_is_special(m)) { result += PawnEndgameExtension[PvNode]; @@ -362,27 +339,24 @@ void init_search() { int64_t perft(Position& pos, Depth depth) { - MoveStack mlist[MAX_MOVES]; StateInfo st; - Move m; int64_t sum = 0; // Generate all legal moves - MoveStack* last = generate(pos, mlist); + MoveList ml(pos); // If we are at the last ply we don't need to do and undo // the moves, just to count them. if (depth <= ONE_PLY) - return int(last - mlist); + return ml.size(); // Loop through all legal moves CheckInfo ci(pos); - for (MoveStack* cur = mlist; cur != last; cur++) + for ( ; !ml.end(); ++ml) { - m = cur->move; - pos.do_move(m, st, ci, pos.move_gives_check(m, ci)); + pos.do_move(ml.move(), st, ci, pos.move_gives_check(ml.move(), ci)); sum += perft(pos, depth - ONE_PLY); - pos.undo_move(m); + pos.undo_move(ml.move()); } return sum; } @@ -404,6 +378,9 @@ bool think(Position& pos, const SearchLimits& limits, Move searchMoves[]) { Limits = limits; TimeMgr.init(Limits, pos.startpos_ply_counter()); + // Set output steram in normal or chess960 mode + cout << set960(pos.is_chess960()); + // Set best NodesBetweenPolls interval to avoid lagging under time pressure if (Limits.maxNodes) NodesBetweenPolls = Min(Limits.maxNodes, 30000); @@ -417,8 +394,8 @@ bool think(Position& pos, const SearchLimits& limits, Move searchMoves[]) { // Look for a book move if (Options["OwnBook"].value()) { - if (Options["Book File"].value() != book.name()) - book.open(Options["Book File"].value()); + if (Options["Book File"].value() != book.name()) + book.open(Options["Book File"].value()); Move bookMove = book.get_move(pos, Options["Best Book Move"].value()); if (bookMove != MOVE_NONE) @@ -463,7 +440,7 @@ 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()) { - std::string name = Options["Search Log Filename"].value(); + string name = Options["Search Log Filename"].value(); LogFile.open(name.c_str(), std::ios::out | std::ios::app); if (LogFile.is_open()) @@ -480,8 +457,6 @@ bool think(Position& pos, const SearchLimits& limits, Move searchMoves[]) { Move ponderMove = MOVE_NONE; Move bestMove = id_loop(pos, searchMoves, &ponderMove); - cout << "info" << speed_to_uci(pos.nodes_searched()) << endl; - // Write final search statistics and close log file if (LogFile.is_open()) { @@ -531,7 +506,7 @@ namespace { SearchStack ss[PLY_MAX_PLUS_2]; Value bestValues[PLY_MAX_PLUS_2]; int bestMoveChanges[PLY_MAX_PLUS_2]; - int depth, selDepth, aspirationDelta; + int depth, aspirationDelta; Value value, alpha, beta; Move bestMove, easyMove, skillBest, skillPonder; @@ -541,18 +516,17 @@ namespace { H.clear(); *ponderMove = bestMove = easyMove = skillBest = skillPonder = MOVE_NONE; depth = aspirationDelta = 0; - alpha = -VALUE_INFINITE, beta = VALUE_INFINITE; + value = alpha = -VALUE_INFINITE, beta = VALUE_INFINITE; ss->currentMove = MOVE_NULL; // Hack to skip update_gains() // Moves to search are verified and copied Rml.init(pos, searchMoves); // Handle special case of searching on a mate/stalemate position - if (Rml.size() == 0) + if (!Rml.size()) { - cout << "info depth 0 score " - << value_to_uci(pos.in_check() ? -VALUE_MATE : VALUE_DRAW) - << endl; + cout << "info" << depth_to_uci(DEPTH_ZERO) + << score_to_uci(pos.in_check() ? -VALUE_MATE : VALUE_DRAW, alpha, beta) << endl; return MOVE_NONE; } @@ -560,56 +534,100 @@ namespace { // Iterative deepening loop until requested to stop or target depth reached while (!StopRequest && ++depth <= PLY_MAX && (!Limits.maxDepth || depth <= Limits.maxDepth)) { + // Remember best moves and values from previous iteration + RootMoveList prevRml = Rml; + Rml.bestMoveChanges = 0; - cout << set960(pos.is_chess960()) << "info depth " << depth << endl; - // Calculate dynamic aspiration window based on previous iterations - if (MultiPV == 1 && depth >= 5 && abs(bestValues[depth - 1]) < VALUE_KNOWN_WIN) + // MultiPV iteration loop + for (MultiPVIteration = 0; MultiPVIteration < Min(MultiPV, (int)Rml.size()); MultiPVIteration++) { - int prevDelta1 = bestValues[depth - 1] - bestValues[depth - 2]; - int prevDelta2 = bestValues[depth - 2] - bestValues[depth - 3]; - - aspirationDelta = Min(Max(abs(prevDelta1) + abs(prevDelta2) / 2, 16), 24); - aspirationDelta = (aspirationDelta + 7) / 8 * 8; // Round to match grainSize - - alpha = Max(bestValues[depth - 1] - aspirationDelta, -VALUE_INFINITE); - beta = Min(bestValues[depth - 1] + aspirationDelta, VALUE_INFINITE); - } - - // 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() - value = search(pos, ss+1, alpha, beta, depth * ONE_PLY); - - // Write PV back to transposition table in case the relevant entries - // have been overwritten during the search. - for (int i = 0; i < Min(MultiPV, (int)Rml.size()); i++) - Rml[i].insert_pv_in_tt(pos); + // Calculate dynamic aspiration window based on previous iterations + if (depth >= 5 && abs(prevRml[MultiPVIteration].pv_score) < VALUE_KNOWN_WIN) + { + int prevDelta1 = bestValues[depth - 1] - bestValues[depth - 2]; + int prevDelta2 = bestValues[depth - 2] - bestValues[depth - 3]; - // Value cannot be trusted. Break out immediately! - if (StopRequest) - break; + aspirationDelta = Min(Max(abs(prevDelta1) + abs(prevDelta2) / 2, 16), 24); + aspirationDelta = (aspirationDelta + 7) / 8 * 8; // Round to match grainSize - // 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); - aspirationDelta += aspirationDelta / 2; + alpha = Max(prevRml[MultiPVIteration].pv_score - aspirationDelta, -VALUE_INFINITE); + beta = Min(prevRml[MultiPVIteration].pv_score + aspirationDelta, VALUE_INFINITE); } - else if (value <= alpha) + else { - AspirationFailLow = true; - StopOnPonderhit = false; - - alpha = Max(alpha - aspirationDelta, -VALUE_INFINITE); - aspirationDelta += aspirationDelta / 2; + alpha = -VALUE_INFINITE; + beta = VALUE_INFINITE; } - else - break; - } while (abs(value) < VALUE_KNOWN_WIN); + // 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() + 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); + + // Write PV back to transposition table in case the relevant entries + // have been overwritten during the search. + for (int i = 0; i <= MultiPVIteration; i++) + Rml[i].insert_pv_in_tt(pos); + + // Value cannot be trusted. Break out immediately! + 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 ((value > alpha && value < beta) || current_search_time() > 2000) + for (int i = 0; i < Min(UCIMultiPV, (int)Rml.size()); i++) + { + bool updated = (i <= MultiPVIteration); + + if (depth == 1 && !updated) + continue; + + const RootMoveList& rml = (updated ? Rml : prevRml); + + cout << "info" + << depth_to_uci((updated ? depth : depth - 1) * ONE_PLY) + << (i == MultiPVIteration ? score_to_uci(rml[i].pv_score, alpha, beta) + : score_to_uci(rml[i].pv_score)) + << 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. + if (value >= beta) + { + beta = Min(beta + aspirationDelta, VALUE_INFINITE); + aspirationDelta += aspirationDelta / 2; + } + else if (value <= alpha) + { + AspirationFailLow = true; + StopOnPonderhit = false; + + alpha = Max(alpha - aspirationDelta, -VALUE_INFINITE); + aspirationDelta += aspirationDelta / 2; + } + else + break; + + } while (abs(value) < VALUE_KNOWN_WIN); + } // Collect info about search result bestMove = Rml[0].pv[0]; @@ -621,18 +639,8 @@ namespace { if (SkillLevelEnabled && depth == 1 + SkillLevel) do_skill_level(&skillBest, &skillPonder); - // Retrieve max searched depth among threads - selDepth = 0; - for (int i = 0; i < Threads.size(); i++) - if (Threads[i].maxPly > selDepth) - selDepth = Threads[i].maxPly; - - // Send PV line to GUI and to log file - for (int i = 0; i < Min(UCIMultiPV, (int)Rml.size()); i++) - cout << Rml[i].pv_info_to_uci(pos, depth, selDepth, alpha, beta, i) << endl; - if (LogFile.is_open()) - LogFile << pretty_pv(pos, depth, value, current_search_time(), Rml[0].pv) << endl; + LogFile << 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 if (depth == 1 && (Rml.size() == 1 || Rml[0].pv_score > Rml[1].pv_score + EasyMoveMargin)) @@ -643,12 +651,6 @@ namespace { // Check for some early stop condition if (!StopRequest && Limits.useTimeManagement()) { - // Stop search early when the last two iterations returned a mate score - if ( depth >= 5 - && abs(bestValues[depth]) >= VALUE_MATE_IN_PLY_MAX - && abs(bestValues[depth - 1]) >= VALUE_MATE_IN_PLY_MAX) - StopRequest = true; - // 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. @@ -717,7 +719,6 @@ namespace { StateInfo st; const TTEntry *tte; Key posKey; - Bitboard pinned; Move ttMove, move, excludedMove, threatMove; Depth ext, newDepth; ValueType vt; @@ -737,7 +738,14 @@ namespace { if (PvNode && thread.maxPly < ss->ply) thread.maxPly = ss->ply; - if (SpNode) + // Step 1. Initialize node and poll. Polling can abort search + if (!SpNode) + { + ss->currentMove = ss->bestMove = threatMove = (ss+1)->excludedMove = MOVE_NONE; + (ss+1)->skipNullMove = false; (ss+1)->reduction = DEPTH_ZERO; + (ss+2)->killers[0] = (ss+2)->killers[1] = MOVE_NONE; + } + else { sp = ss->sp; tte = NULL; @@ -746,11 +754,6 @@ namespace { goto split_point_start; } - // Step 1. Initialize node and poll. Polling can abort search - ss->currentMove = ss->bestMove = threatMove = (ss+1)->excludedMove = MOVE_NONE; - (ss+1)->skipNullMove = false; (ss+1)->reduction = DEPTH_ZERO; - (ss+2)->killers[0] = (ss+2)->killers[1] = MOVE_NONE; - if (pos.thread() == 0 && ++NodesSincePoll > NodesBetweenPolls) { NodesSincePoll = 0; @@ -764,25 +767,28 @@ namespace { return VALUE_DRAW; // Step 3. Mate distance pruning - alpha = Max(value_mated_in(ss->ply), alpha); - beta = Min(value_mate_in(ss->ply+1), beta); - if (alpha >= beta) - return alpha; + if (!RootNode) + { + alpha = Max(value_mated_in(ss->ply), alpha); + beta = Min(value_mate_in(ss->ply+1), beta); + if (alpha >= beta) + return alpha; + } // Step 4. Transposition table lookup // We don't want the score of a partial search to overwrite a previous full search // TT value, so we use a different position key in case of an excluded move. excludedMove = ss->excludedMove; posKey = excludedMove ? pos.get_exclusion_key() : pos.get_key(); - tte = TT.probe(posKey); ttMove = 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 - // smooth experience in analysis mode. - if (tte && (PvNode ? tte->depth() >= depth && tte->type() == VALUE_TYPE_EXACT - : ok_to_use_TT(tte, depth, beta, ss->ply))) + // smooth experience in analysis mode. We don't probe at Root nodes otherwise + // we should also update RootMoveList to avoid bogus output. + if (!RootNode && tte && (PvNode ? tte->depth() >= depth && tte->type() == VALUE_TYPE_EXACT + : ok_to_use_TT(tte, depth, beta, ss->ply))) { TT.refresh(tte); ss->bestMove = ttMove; // Can be MOVE_NONE @@ -914,13 +920,13 @@ namespace { assert(rdepth >= ONE_PLY); - MovePicker mp(pos, ttMove, H, Position::see_value(pos.captured_piece_type())); - pinned = pos.pinned_pieces(pos.side_to_move()); + MovePicker mp(pos, ttMove, H, pos.captured_piece_type()); + CheckInfo ci(pos); while ((move = mp.get_next_move()) != MOVE_NONE) - if (pos.pl_move_is_legal(move, pinned)) + if (pos.pl_move_is_legal(move, ci.pinned)) { - pos.do_move(move, st); + pos.do_move(move, st, ci, pos.move_gives_check(move, ci)); value = -search(pos, ss+1, -rbeta, -rbeta+1, rdepth); pos.undo_move(move); if (value >= rbeta) @@ -946,9 +952,8 @@ namespace { split_point_start: // At split points actual search starts from here // Initialize a MovePicker object for the current position - MovePickerExt mp(pos, ttMove, depth, H, ss, PvNode ? -VALUE_INFINITE : beta); + MovePickerExt mp(pos, RootNode ? Rml[MultiPVIteration].pv[0] : ttMove, depth, H, ss, PvNode ? -VALUE_INFINITE : beta); CheckInfo ci(pos); - pinned = pos.pinned_pieces(pos.side_to_move()); ss->bestMove = MOVE_NONE; futilityBase = ss->eval + ss->evalMargin; singularExtensionNode = !RootNode @@ -975,8 +980,14 @@ split_point_start: // At split points actual search starts from here if (move == excludedMove) continue; - // At PV and SpNode nodes we want the moves to be legal - if ((PvNode || SpNode) && !pos.pl_move_is_legal(move, pinned)) + // 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. + if (RootNode && !Rml.find(move, MultiPVIteration)) + continue; + + // At PV and SpNode nodes we want all moves to be legal since the beginning + if ((PvNode || SpNode) && !pos.pl_move_is_legal(move, ci.pinned)) continue; if (SpNode) @@ -1003,15 +1014,16 @@ split_point_start: // At split points actual search starts from here cout << "info" << speed_to_uci(pos.nodes_searched()) << endl; } + // For long searches send current move info to GUI if (current_search_time() > 2000) - cout << "info currmove " << move - << " currmovenumber " << moveCount << endl; + cout << "info" << depth_to_uci(depth) + << " currmove " << move << " currmovenumber " << moveCount + MultiPVIteration << 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 ? 1000 : MultiPV : 1)); + isPvMove = (PvNode && moveCount <= ((RootNode && depth <= ONE_PLY) ? MAX_MOVES : 1)); givesCheck = pos.move_gives_check(move, ci); - captureOrPromotion = pos.move_is_capture(move) || move_is_promotion(move); + captureOrPromotion = pos.move_is_capture_or_promotion(move); // Step 12. Decide the new search depth ext = extension(pos, move, captureOrPromotion, givesCheck, &dangerous); @@ -1023,7 +1035,7 @@ split_point_start: // At split points actual search starts from here // a margin then we extend ttMove. if ( singularExtensionNode && move == ttMove - && pos.pl_move_is_legal(move, pinned) + && pos.pl_move_is_legal(move, ci.pinned) && ext < ONE_PLY) { Value ttValue = value_from_tt(tte->value(), ss->ply); @@ -1098,54 +1110,46 @@ split_point_start: // At split points actual search starts from here } // Check for legality only before to do the move - if (!pos.pl_move_is_legal(move, pinned)) + if (!pos.pl_move_is_legal(move, ci.pinned)) { moveCount--; continue; } ss->currentMove = move; + if (!SpNode && !captureOrPromotion) + movesSearched[playedMoveCount++] = move; // Step 14. Make the move pos.do_move(move, st, ci, givesCheck); - if (!SpNode && !captureOrPromotion) - movesSearched[playedMoveCount++] = move; - // Step extra. pv search (only in PV nodes) // The first move in list is the expected PV if (isPvMove) - { - // Aspiration window is disabled in multi-pv case - if (RootNode && MultiPV > 1) - alpha = -VALUE_INFINITE; - value = newDepth < ONE_PLY ? -qsearch(pos, ss+1, -beta, -alpha, DEPTH_ZERO) : - search(pos, ss+1, -beta, -alpha, newDepth); - } else { // Step 15. Reduced depth search // If the move fails high will be re-searched at full depth. bool doFullDepthSearch = true; - alpha = SpNode ? sp->alpha : alpha; if ( depth > 3 * ONE_PLY && !captureOrPromotion && !dangerous && !move_is_castle(move) && ss->killers[0] != move - && ss->killers[1] != move) + && ss->killers[1] != move + && (ss->reduction = reduction(depth, moveCount)) != DEPTH_ZERO) { - ss->reduction = reduction(depth, moveCount); - if (ss->reduction) - { - Depth d = newDepth - ss->reduction; - value = d < ONE_PLY ? -qsearch(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO) - : - search(pos, ss+1, -(alpha+1), -alpha, d); - doFullDepthSearch = (value > alpha); - } - ss->reduction = DEPTH_ZERO; // Restore original reduction + Depth d = newDepth - ss->reduction; + alpha = SpNode ? sp->alpha : alpha; + + value = d < ONE_PLY ? -qsearch(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO) + : - search(pos, ss+1, -(alpha+1), -alpha, d); + + ss->reduction = DEPTH_ZERO; + doFullDepthSearch = (value > alpha); } // Step 16. Full depth search @@ -1177,29 +1181,23 @@ split_point_start: // At split points actual search starts from here alpha = sp->alpha; } - if (value > bestValue && !(SpNode && thread.cutoff_occurred())) + if (value > bestValue) { bestValue = value; + ss->bestMove = move; - if (SpNode) - sp->bestValue = value; + if ( !RootNode + && PvNode + && value > alpha + && value < beta) // We want always alpha < beta + alpha = value; - if (!RootNode && value > alpha) + if (SpNode && !thread.cutoff_occurred()) { - if (PvNode && value < beta) // We want always alpha < beta - { - alpha = value; - - if (SpNode) - sp->alpha = value; - } - else if (SpNode) - sp->is_betaCutoff = true; - - ss->bestMove = move; - - if (SpNode) - sp->ss->bestMove = move; + sp->bestValue = value; + sp->ss->bestMove = move; + sp->alpha = alpha; + sp->is_betaCutoff = (value >= beta); } } @@ -1214,15 +1212,15 @@ split_point_start: // At split points actual search starts from here break; // Remember searched nodes counts for this move - mp.rm->nodes += pos.nodes_searched() - nodes; + RootMove* rm = Rml.find(move); + rm->nodes += pos.nodes_searched() - nodes; // PV move or new best move ? if (isPvMove || value > alpha) { // Update PV - ss->bestMove = move; - mp.rm->pv_score = value; - mp.rm->extract_pv_from_tt(pos); + rm->pv_score = value; + rm->extract_pv_from_tt(pos); // We record how often the best move has been changed in each // iteration. This information is used for time management: When @@ -1230,17 +1228,15 @@ split_point_start: // At split points actual search starts from here if (!isPvMove && MultiPV == 1) Rml.bestMoveChanges++; - Rml.sort_multipv(moveCount); - - // Update alpha. In multi-pv we don't use aspiration window, so - // set alpha equal to minimum score among the PV lines. - if (MultiPV > 1) - alpha = Rml[Min(moveCount, MultiPV) - 1].pv_score; // FIXME why moveCount? - else if (value > alpha) + // Update alpha. + if (value > alpha) alpha = value; } else - mp.rm->pv_score = -VALUE_INFINITE; + // All other moves but the PV are set to the lowest value, this + // is not a problem when sorting becuase sort is stable and move + // position in the list is preserved, just the PV is pushed up. + rm->pv_score = -VALUE_INFINITE; } // RootNode @@ -1276,8 +1272,7 @@ 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(move) - && !move_is_promotion(move)) + && !pos.move_is_capture_or_promotion(move)) { if (move != ss->killers[0]) { @@ -1391,7 +1386,6 @@ split_point_start: // At split points actual search starts from here // be generated. MovePicker mp(pos, ttMove, depth, H, move_to((ss-1)->currentMove)); CheckInfo ci(pos); - Bitboard pinned = pos.pinned_pieces(pos.side_to_move()); // Loop through the moves until no moves remain or a beta cutoff occurs while ( alpha < beta @@ -1411,7 +1405,7 @@ split_point_start: // At split points actual search starts from here && !pos.move_is_passed_pawn_push(move)) { futilityValue = futilityBase - + pos.endgame_value_of_piece_on(move_to(move)) + + piece_value_endgame(pos.piece_on(move_to(move))) + (move_is_ep(move) ? PawnValueEndgame : VALUE_ZERO); if (futilityValue < alpha) @@ -1448,8 +1442,7 @@ split_point_start: // At split points actual search starts from here && !inCheck && givesCheck && move != ttMove - && !pos.move_is_capture(move) - && !move_is_promotion(move) + && !pos.move_is_capture_or_promotion(move) && ss->eval + PawnValueMidgame / 4 < beta && !check_is_dangerous(pos, move, futilityBase, beta, &bestValue)) { @@ -1460,7 +1453,7 @@ split_point_start: // At split points actual search starts from here } // Check for legality only before to do the move - if (!pos.pl_move_is_legal(move, pinned)) + if (!pos.pl_move_is_legal(move, ci.pinned)) continue; // Update current move @@ -1524,23 +1517,23 @@ split_point_start: // At split points actual search starts from here newAtt = pos.attacks_from(pc, to, occ); // Rule 1. Checks which give opponent's king at most one escape square are dangerous - b = kingAtt & ~pos.pieces_of_color(them) & ~newAtt & ~(1ULL << to); + b = kingAtt & ~pos.pieces(them) & ~newAtt & ~(1ULL << to); if (!(b && (b & (b - 1)))) return true; // Rule 2. Queen contact check is very dangerous - if ( type_of_piece(pc) == QUEEN + if ( piece_type(pc) == QUEEN && bit_is_set(kingAtt, to)) return true; // Rule 3. Creating new double threats with checks - b = pos.pieces_of_color(them) & newAtt & ~oldAtt & ~(1ULL << ksq); + b = pos.pieces(them) & newAtt & ~oldAtt & ~(1ULL << ksq); while (b) { victimSq = pop_1st_bit(&b); - futilityValue = futilityBase + pos.endgame_value_of_piece_on(victimSq); + futilityValue = futilityBase + piece_value_endgame(pos.piece_on(victimSq)); // Note that here we generate illegal "double move"! if ( futilityValue >= beta @@ -1566,7 +1559,8 @@ split_point_start: // At split points actual search starts from here bool connected_moves(const Position& pos, Move m1, Move m2) { Square f1, t1, f2, t2; - Piece p; + Piece p1, p2; + Square ksq; assert(m1 && move_is_ok(m1)); assert(m2 && move_is_ok(m2)); @@ -1584,26 +1578,24 @@ split_point_start: // At split points actual search starts from here return true; // Case 3: Moving through the vacated square - if ( piece_is_slider(pos.piece_on(f2)) + p2 = pos.piece_on(f2); + if ( piece_is_slider(p2) && bit_is_set(squares_between(f2, t2), f1)) return true; // Case 4: The destination square for m2 is defended by the moving piece in m1 - p = pos.piece_on(t1); - if (bit_is_set(pos.attacks_from(p, t1), t2)) + p1 = pos.piece_on(t1); + if (bit_is_set(pos.attacks_from(p1, t1), t2)) return true; // Case 5: Discovered check, checking piece is the piece moved in m1 - if ( piece_is_slider(p) - && bit_is_set(squares_between(t1, pos.king_square(pos.side_to_move())), f2) - && !bit_is_set(squares_between(t1, pos.king_square(pos.side_to_move())), t2)) + ksq = pos.king_square(pos.side_to_move()); + if ( piece_is_slider(p1) + && bit_is_set(squares_between(t1, ksq), f2)) { - // discovered_check_candidates() works also if the Position's side to - // move is the opposite of the checking piece. - Color them = opposite_color(pos.side_to_move()); - Bitboard dcCandidates = pos.discovered_check_candidates(them); - - if (bit_is_set(dcCandidates, f2)) + Bitboard occ = pos.occupied_squares(); + clear_bit(&occ, f2); + if (bit_is_set(pos.attacks_from(p1, t1, occ), ksq)) return true; } return false; @@ -1648,8 +1640,7 @@ split_point_start: // At split points actual search starts from here assert(move_is_ok(m)); assert(threat && move_is_ok(threat)); - assert(!pos.move_gives_check(m)); - assert(!pos.move_is_capture(m) && !move_is_promotion(m)); + assert(!pos.move_is_capture_or_promotion(m)); assert(!pos.move_is_passed_pawn_push(m)); Square mfrom, mto, tfrom, tto; @@ -1666,8 +1657,8 @@ 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) - && ( pos.midgame_value_of_piece_on(tfrom) >= pos.midgame_value_of_piece_on(tto) - || pos.type_of_piece_on(tfrom) == KING) + && ( piece_value_midgame(pos.piece_on(tfrom)) >= piece_value_midgame(pos.piece_on(tto)) + || piece_type(pos.piece_on(tfrom)) == KING) && pos.move_attacks_square(m, tto)) return true; @@ -1764,21 +1755,23 @@ split_point_start: // At split points actual search starts from here } - // value_to_uci() converts a value to a string suitable for use with the UCI + // score_to_uci() converts a value to a string suitable for use with the UCI // protocol specifications: // // cp The score from the engine's point of view in centipawns. // mate Mate in y moves, not plies. If the engine is getting mated // use negative values for y. - std::string value_to_uci(Value v) { + string score_to_uci(Value v, Value alpha, Value beta) { std::stringstream s; if (abs(v) < VALUE_MATE - PLY_MAX * ONE_PLY) - s << "cp " << int(v) * 100 / int(PawnValueMidgame); // Scale to centipawns + s << " score cp " << int(v) * 100 / int(PawnValueMidgame); // Scale to centipawns else - s << "mate " << (v > 0 ? VALUE_MATE - v + 1 : -VALUE_MATE - v) / 2; + s << " score mate " << (v > 0 ? VALUE_MATE - v + 1 : -VALUE_MATE - v) / 2; + + s << (v >= beta ? " lowerbound" : v <= alpha ? " upperbound" : ""); return s.str(); } @@ -1787,18 +1780,134 @@ split_point_start: // At split points actual search starts from here // speed_to_uci() returns a string with time stats of current search suitable // to be sent to UCI gui. - std::string speed_to_uci(int64_t nodes) { + string speed_to_uci(int64_t nodes) { std::stringstream s; int t = current_search_time(); s << " nodes " << nodes - << " nps " << (t > 0 ? int(nodes * 1000 / t) : 0) + << " nps " << (t > 0 ? int(nodes * 1000 / t) : 0) << " time " << t; return s.str(); } + // pv_to_uci() returns a string with information on the current PV line + // formatted according to UCI specification. + + string pv_to_uci(const Move pv[], int pvNum, bool chess960) { + + std::stringstream s; + + s << " multipv " << pvNum << " pv " << set960(chess960); + + for ( ; *pv != MOVE_NONE; pv++) + s << *pv << " "; + + return s.str(); + } + + // depth_to_uci() returns a string with information on the current depth and + // seldepth formatted according to UCI specification. + + string depth_to_uci(Depth depth) { + + std::stringstream s; + + // Retrieve max searched depth among threads + int selDepth = 0; + for (int i = 0; i < Threads.size(); i++) + if (Threads[i].maxPly > selDepth) + selDepth = Threads[i].maxPly; + + s << " depth " << depth / ONE_PLY << " seldepth " << selDepth; + + return s.str(); + } + + string time_to_string(int millisecs) { + + const int MSecMinute = 1000 * 60; + const int MSecHour = 1000 * 60 * 60; + + int hours = millisecs / MSecHour; + int minutes = (millisecs % MSecHour) / MSecMinute; + int seconds = ((millisecs % MSecHour) % MSecMinute) / 1000; + + std::stringstream s; + + if (hours) + s << hours << ':'; + + s << std::setfill('0') << std::setw(2) << minutes << ':' << std::setw(2) << seconds; + return s.str(); + } + + string score_to_string(Value v) { + + std::stringstream s; + + if (v >= VALUE_MATE_IN_PLY_MAX) + s << "#" << (VALUE_MATE - v + 1) / 2; + else if (v <= VALUE_MATED_IN_PLY_MAX) + s << "-#" << (VALUE_MATE + v) / 2; + else + s << std::setprecision(2) << std::fixed << std::showpos << float(v) / PawnValueMidgame; + + return s.str(); + } + + // pretty_pv() creates a human-readable string from a position and a PV. + // It is used to write search information to the log file (which is created + // when the UCI parameter "Use Search Log" is "true"). + + string pretty_pv(Position& pos, int depth, Value value, int time, Move pv[]) { + + const int64_t K = 1000; + const int64_t M = 1000000; + const int startColumn = 28; + const size_t maxLength = 80 - startColumn; + + StateInfo state[PLY_MAX_PLUS_2], *st = state; + Move* m = pv; + string san; + std::stringstream s; + size_t length = 0; + + // First print depth, score, time and searched nodes... + s << set960(pos.is_chess960()) + << std::setw(2) << depth + << std::setw(8) << score_to_string(value) + << std::setw(8) << time_to_string(time); + + if (pos.nodes_searched() < M) + s << std::setw(8) << pos.nodes_searched() / 1 << " "; + else if (pos.nodes_searched() < K * M) + s << std::setw(7) << pos.nodes_searched() / K << "K "; + else + s << std::setw(7) << pos.nodes_searched() / M << "M "; + + // ...then print the full PV line in short algebraic notation + while (*m != MOVE_NONE) + { + san = move_to_san(pos, *m); + length += san.length() + 1; + + if (length > maxLength) + { + length = san.length() + 1; + s << "\n" + string(startColumn, ' '); + } + s << san << ' '; + + pos.do_move(*m++, *st++); + } + + // Restore original position before to leave + while (m != pv) pos.undo_move(*--m); + + return s.str(); + } // poll() performs two different functions: It polls for user input, and it // looks at the time consumed so far and decides if it's time to abort the @@ -1813,7 +1922,7 @@ split_point_start: // At split points actual search starts from here if (input_available()) { // We are line oriented, don't read single chars - std::string command; + string command; if (!std::getline(std::cin, command) || command == "quit") { @@ -1888,7 +1997,7 @@ split_point_start: // At split points actual search starts from here void wait_for_stop_or_ponderhit() { - std::string command; + string command; // Wait for a command from stdin while ( std::getline(std::cin, command) @@ -1945,54 +2054,40 @@ split_point_start: // At split points actual search starts from here /// RootMove and RootMoveList method's definitions - RootMove::RootMove() { - - nodes = 0; - pv_score = non_pv_score = -VALUE_INFINITE; - pv[0] = MOVE_NONE; - } - - RootMove& RootMove::operator=(const RootMove& rm) { - - const Move* src = rm.pv; - Move* dst = pv; - - // Avoid a costly full rm.pv[] copy - do *dst++ = *src; while (*src++ != MOVE_NONE); - - nodes = rm.nodes; - pv_score = rm.pv_score; - non_pv_score = rm.non_pv_score; - return *this; - } - void RootMoveList::init(Position& pos, Move searchMoves[]) { - MoveStack mlist[MAX_MOVES]; Move* sm; - - clear(); bestMoveChanges = 0; + clear(); // Generate all legal moves and add them to RootMoveList - MoveStack* last = generate(pos, mlist); - for (MoveStack* cur = mlist; cur != last; cur++) + for (MoveList ml(pos); !ml.end(); ++ml) { - // If we have a searchMoves[] list then verify cur->move + // If we have a searchMoves[] list then verify the move // is in the list before to add it. - for (sm = searchMoves; *sm && *sm != cur->move; sm++) {} + for (sm = searchMoves; *sm && *sm != ml.move(); sm++) {} - if (searchMoves[0] && *sm != cur->move) + if (sm != searchMoves && *sm != ml.move()) continue; RootMove rm; - rm.pv[0] = cur->move; - rm.pv[1] = MOVE_NONE; + rm.pv.push_back(ml.move()); + rm.pv.push_back(MOVE_NONE); rm.pv_score = -VALUE_INFINITE; + rm.nodes = 0; push_back(rm); } } + RootMove* RootMoveList::find(const Move& m, int startIndex) { + + for (size_t i = startIndex; i < size(); i++) + if ((*this)[i].pv[0] == m) + return &(*this)[i]; + + return NULL; + } + // extract_pv_from_tt() builds a PV by adding moves from the transposition table. // We consider also failing high nodes and not only VALUE_TYPE_EXACT nodes. This // allow to always have a ponder move even when we fail high at root and also a @@ -2003,22 +2098,26 @@ split_point_start: // At split points actual search starts from here StateInfo state[PLY_MAX_PLUS_2], *st = state; TTEntry* tte; int ply = 1; + Move m = pv[0]; - assert(pv[0] != MOVE_NONE && pos.move_is_pl(pv[0])); + assert(m != MOVE_NONE && pos.move_is_pl(m)); - pos.do_move(pv[0], *st++); + pv.clear(); + pv.push_back(m); + pos.do_move(m, *st++); while ( (tte = TT.probe(pos.get_key())) != NULL && tte->move() != MOVE_NONE && pos.move_is_pl(tte->move()) - && pos.pl_move_is_legal(tte->move(), pos.pinned_pieces(pos.side_to_move())) + && pos.pl_move_is_legal(tte->move(), pos.pinned_pieces()) && ply < PLY_MAX && (!pos.is_draw() || ply < 2)) { - pv[ply] = tte->move(); - pos.do_move(pv[ply++], *st++); + pv.push_back(tte->move()); + pos.do_move(tte->move(), *st++); + ply++; } - pv[ply] = MOVE_NONE; + pv.push_back(MOVE_NONE); do pos.undo_move(pv[--ply]); while (ply); } @@ -2053,61 +2152,6 @@ split_point_start: // At split points actual search starts from here do pos.undo_move(pv[--ply]); while (ply); } - - // pv_info_to_uci() returns a string with information on the current PV line - // formatted according to UCI specification. - - std::string RootMove::pv_info_to_uci(Position& pos, int depth, int selDepth, Value alpha, - Value beta, int pvIdx) { - std::stringstream s; - - s << "info depth " << depth - << " seldepth " << selDepth - << " multipv " << pvIdx + 1 - << " score " << value_to_uci(pv_score) - << (pv_score >= beta ? " lowerbound" : pv_score <= alpha ? " upperbound" : "") - << speed_to_uci(pos.nodes_searched()) - << " pv "; - - for (Move* m = pv; *m != MOVE_NONE; m++) - s << *m << " "; - - return s.str(); - } - - // Specializations for MovePickerExt in case of Root node - MovePickerExt::MovePickerExt(const Position& p, Move ttm, Depth d, - const History& h, SearchStack* ss, Value b) - : MovePicker(p, ttm, d, h, ss, b), firstCall(true) { - Move move; - Value score = VALUE_ZERO; - - // Score root moves using standard ordering used in main search, the moves - // are scored according to the order in which they are returned by MovePicker. - // This is the second order score that is used to compare the moves when - // the first orders pv_score of both moves are equal. - while ((move = MovePicker::get_next_move()) != MOVE_NONE) - for (rm = Rml.begin(); rm != Rml.end(); ++rm) - if (rm->pv[0] == move) - { - rm->non_pv_score = score--; - break; - } - - Rml.sort(); - rm = Rml.begin(); - } - - Move MovePickerExt::get_next_move() { - - if (!firstCall) - ++rm; - else - firstCall = false; - - return rm != Rml.end() ? rm->pv[0] : MOVE_NONE; - } - } // namespace