X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=08b2c00686cd21de07c440a7e616dcc155dd0e22;hp=70bd1eab463968717a38c9262a65409baada9a09;hb=3701a8e57ded0876bd34ba1bc1afafc631ee059b;hpb=36c0ab3a5056268e22b7215981bf085c01bf635d diff --git a/src/search.cpp b/src/search.cpp index 70bd1eab..08b2c006 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -189,9 +189,6 @@ namespace { // Remaining depth: 1 ply 1.5 ply 2 ply 2.5 ply 3 ply 3.5 ply const Value RazorApprMargins[6] = { Value(0x520), Value(0x300), Value(0x300), Value(0x300), Value(0x300), Value(0x300) }; - // The main transposition table - TranspositionTable TT; - /// Variables initialized by UCI options @@ -202,10 +199,10 @@ namespace { Depth ThreatDepth; // heavy SMP read access // Last seconds noise filtering (LSN) - bool UseLSNFiltering; - bool looseOnTime = false; - int LSNTime; // In milliseconds - Value LSNValue; + const bool UseLSNFiltering = true; + const int LSNTime = 4000; // In milliseconds + const Value LSNValue = value_from_centipawns(200); + bool loseOnTime = false; // Extensions. Array index 0 is used at non-PV nodes, index 1 at PV nodes. // There is heavy SMP read access on these arrays @@ -226,8 +223,7 @@ namespace { // Time managment variables int SearchStartTime; int MaxNodes, MaxDepth; - int MaxSearchTime, AbsoluteMaxSearchTime, ExtraSearchTime; - Move EasyMove; + int MaxSearchTime, AbsoluteMaxSearchTime, ExtraSearchTime, ExactMaxTime; int RootMoveNumber; bool InfiniteSearch; bool PonderSearch; @@ -237,8 +233,6 @@ namespace { bool FailHigh; bool FailLow; bool Problem; - bool PonderingEnabled; - int ExactMaxTime; // Show current line? bool ShowCurrentLine; @@ -271,6 +265,9 @@ namespace { int NodesSincePoll; int NodesBetweenPolls = 30000; + // History table + History H; + /// Functions @@ -289,10 +286,10 @@ namespace { bool move_is_killer(Move m, const SearchStack& ss); Depth extension(const Position& pos, Move m, bool pvNode, bool capture, bool check, bool singleReply, bool mateThreat, bool* dangerous); bool ok_to_do_nullmove(const Position& pos); - bool ok_to_prune(const Position& pos, Move m, Move threat, Depth d, const History& H); + bool ok_to_prune(const Position& pos, Move m, Move threat, Depth d); bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply); bool ok_to_history(const Position& pos, Move m); - void update_history(const Position& pos, Move m, Depth depth, History& H, Move movesSearched[], int moveCount); + void update_history(const Position& pos, Move m, Depth depth, Move movesSearched[], int moveCount); void update_killers(Move m, SearchStack& ss); bool fail_high_ply_1(); @@ -354,7 +351,6 @@ bool think(const Position& pos, bool infinite, bool ponder, int side_to_move, // Initialize global search variables Idle = false; SearchStartTime = get_system_time(); - EasyMove = MOVE_NONE; for (int i = 0; i < THREAD_MAX; i++) { Threads[i].nodes = 0ULL; @@ -374,9 +370,12 @@ bool think(const Position& pos, bool infinite, bool ponder, int side_to_move, // Read UCI option values TT.set_size(get_option_value_int("Hash")); if (button_was_pressed("Clear Hash")) + { TT.clear(); + loseOnTime = false; // reset at the beginning of a new game + } - PonderingEnabled = get_option_value_bool("Ponder"); + bool PonderingEnabled = get_option_value_bool("Ponder"); MultiPV = get_option_value_int("MultiPV"); CheckExtension[1] = Depth(get_option_value_int("Check Extension (PV nodes)")); @@ -407,15 +406,12 @@ bool think(const Position& pos, bool infinite, bool ponder, int side_to_move, if (UseLogFile) LogFile.open(get_option_value_string("Search Log Filename").c_str(), std::ios::out | std::ios::app); - UseLSNFiltering = get_option_value_bool("LSN filtering"); - LSNTime = get_option_value_int("LSN Time Margin (sec)") * 1000; - LSNValue = value_from_centipawns(get_option_value_int("LSN Value Margin")); - MinimumSplitDepth = get_option_value_int("Minimum Split Depth") * OnePly; MaxThreadsPerSplitPoint = get_option_value_int("Maximum Number of Threads per Split Point"); read_weights(pos.side_to_move()); + // Set the number of active threads int newActiveThreads = get_option_value_int("Threads"); if (newActiveThreads != ActiveThreads) { @@ -476,7 +472,6 @@ bool think(const Position& pos, bool infinite, bool ponder, int side_to_move, else NodesBetweenPolls = 30000; - // Write information to search log file if (UseLogFile) LogFile << "Searching: " << pos.to_fen() << std::endl @@ -488,17 +483,19 @@ bool think(const Position& pos, bool infinite, bool ponder, int side_to_move, // We're ready to start thinking. Call the iterative deepening loop function - if (!looseOnTime) + // + // FIXME we really need to cleanup all this LSN ugliness + if (!loseOnTime) { Value v = id_loop(pos, searchMoves); - looseOnTime = ( UseLSNFiltering - && myTime < LSNTime - && myIncrement == 0 - && v < -LSNValue); + loseOnTime = ( UseLSNFiltering + && myTime < LSNTime + && myIncrement == 0 + && v < -LSNValue); } else { - looseOnTime = false; // reset for next match + loseOnTime = false; // reset for next match while (SearchStartTime + myTime + 1000 > get_system_time()) ; // wait here id_loop(pos, searchMoves); // to fail gracefully @@ -627,11 +624,18 @@ namespace { // searchMoves are verified, copied, scored and sorted RootMoveList rml(p, searchMoves); + // Print RootMoveList c'tor startup scoring to the standard output, + // so that we print information also for iteration 1. + std::cout << "info depth " << 1 << "\ninfo depth " << 1 + << " score " << value_to_string(rml.get_move_score(0)) + << " time " << current_search_time() + << " nodes " << nodes_searched() + << " nps " << nps() + << " pv " << rml.get_move(0) << "\n"; + // Initialize TT.new_search(); - for (int i = 0; i < THREAD_MAX; i++) - Threads[i].H.clear(); - + H.clear(); for (int i = 0; i < 3; i++) { ss[i].init(i); @@ -640,7 +644,7 @@ namespace { IterationInfo[1] = IterationInfoType(rml.get_move_score(0), rml.get_move_score(0)); Iteration = 1; - EasyMove = rml.scan_for_easy_move(); + Move EasyMove = rml.scan_for_easy_move(); // Iterative deepening loop while (Iteration < PLY_MAX) @@ -860,8 +864,9 @@ namespace { << " currmovenumber " << i + 1 << std::endl; // Decide search depth for this move + bool moveIsCapture = pos.move_is_capture(move); bool dangerous; - ext = extension(pos, move, true, pos.move_is_capture(move), pos.move_is_check(move), false, false, &dangerous); + ext = extension(pos, move, true, moveIsCapture, pos.move_is_check(move), false, false, &dangerous); newDepth = (Iteration - 2) * OnePly + ext + InitialDepth; // Make the move, and search it @@ -885,15 +890,30 @@ namespace { } else { - value = -search(pos, ss, -alpha, newDepth, 1, true, 0); + if ( newDepth >= 3*OnePly + && i >= MultiPV + LMRPVMoves + && !dangerous + && !moveIsCapture + && !move_is_promotion(move) + && !move_is_castle(move)) + { + ss[0].reduction = OnePly; + value = -search(pos, ss, -alpha, newDepth-OnePly, 1, true, 0); + } else + value = alpha + 1; // Just to trigger next condition + if (value > alpha) { - // Fail high! Set the boolean variable FailHigh to true, and - // re-search the move with a big window. The variable FailHigh is - // used for time managment: We try to avoid aborting the search - // prematurely during a fail high research. - FailHigh = true; - value = -search_pv(pos, ss, -beta, -alpha, newDepth, 1, 0); + value = -search(pos, ss, -alpha, newDepth, 1, true, 0); + if (value > alpha) + { + // Fail high! Set the boolean variable FailHigh to true, and + // re-search the move with a big window. The variable FailHigh is + // used for time managment: We try to avoid aborting the search + // prematurely during a fail high research. + FailHigh = true; + value = -search_pv(pos, ss, -beta, -alpha, newDepth, 1, 0); + } } } @@ -927,6 +947,7 @@ namespace { // Update PV rml.set_move_score(i, value); update_pv(ss, 0); + TT.extract_pv(pos, ss[0].pv); rml.set_move_pv(i, ss[0].pv); if (MultiPV == 1) @@ -940,6 +961,8 @@ namespace { // Print search information to the standard output std::cout << "info depth " << Iteration << " score " << value_to_string(value) + << ((value >= beta)? + " lowerbound" : ((value <= alpha)? " upperbound" : "")) << " time " << current_search_time() << " nodes " << nodes_searched() << " nps " << nps() @@ -1043,16 +1066,16 @@ namespace { // Initialize a MovePicker object for the current position, and prepare // to search all moves - MovePicker mp = MovePicker(pos, ttMove, depth, Threads[threadID].H, &ss[ply]); - Move move, movesSearched[256]; int moveCount = 0; Value value, bestValue = -VALUE_INFINITE; - Bitboard dcCandidates = mp.discovered_check_candidates(); Color us = pos.side_to_move(); bool isCheck = pos.is_check(); bool mateThreat = pos.has_mate_threat(opposite_color(us)); + MovePicker mp = MovePicker(pos, ttMove, depth, H, &ss[ply]); + Bitboard dcCandidates = mp.discovered_check_candidates(); + // Loop through all legal moves until no moves remain or a beta cutoff // occurs. while ( alpha < beta @@ -1061,7 +1084,7 @@ namespace { { assert(move_is_ok(move)); - bool singleReply = (isCheck && mp.number_of_moves() == 1); + bool singleReply = (isCheck && mp.number_of_evasions() == 1); bool moveIsCheck = pos.move_is_check(move, dcCandidates); bool moveIsCapture = pos.move_is_capture(move); @@ -1082,7 +1105,7 @@ namespace { { // Try to reduce non-pv search depth by one ply if move seems not problematic, // if the move fails high will be re-searched at full depth. - if ( depth >= 2*OnePly + if ( depth >= 3*OnePly && moveCount >= LMRPVMoves && !dangerous && !moveIsCapture @@ -1172,7 +1195,7 @@ namespace { Move m = ss[ply].pv[ply]; if (ok_to_history(pos, m)) // Only non capture moves are considered { - update_history(pos, m, depth, Threads[threadID].H, movesSearched, moveCount); + update_history(pos, m, depth, movesSearched, moveCount); update_killers(m, ss[ply]); } TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, depth, m); @@ -1251,11 +1274,7 @@ namespace { pos.undo_null_move(); - if (value_is_mate(nullValue)) - { - /* Do not return unproven mates */ - } - else if (nullValue >= beta) + if (nullValue >= beta) { if (depth < 6 * OnePly) return beta; @@ -1304,7 +1323,7 @@ namespace { // Initialize a MovePicker object for the current position, and prepare // to search all moves. - MovePicker mp = MovePicker(pos, ttMove, depth, Threads[threadID].H, &ss[ply]); + MovePicker mp = MovePicker(pos, ttMove, depth, H, &ss[ply]); Move move, movesSearched[256]; int moveCount = 0; @@ -1314,6 +1333,10 @@ namespace { bool useFutilityPruning = depth < SelectiveDepth && !isCheck; + // Avoid calling evaluate() if we already have the score in TT + if (tte && (tte->type() & VALUE_TYPE_EVAL)) + futilityValue = value_from_tt(tte->value(), ply) + FutilityMargins[int(depth) - 2]; + // Loop through all legal moves until no moves remain or a beta cutoff // occurs. while ( bestValue < beta @@ -1322,7 +1345,7 @@ namespace { { assert(move_is_ok(move)); - bool singleReply = (isCheck && mp.number_of_moves() == 1); + bool singleReply = (isCheck && mp.number_of_evasions() == 1); bool moveIsCheck = pos.move_is_check(move, dcCandidates); bool moveIsCapture = pos.move_is_capture(move); @@ -1341,7 +1364,7 @@ namespace { { // History pruning. See ok_to_prune() definition if ( moveCount >= 2 + int(depth) - && ok_to_prune(pos, move, ss[ply].threatMove, depth, Threads[threadID].H)) + && ok_to_prune(pos, move, ss[ply].threatMove, depth)) continue; // Value based pruning @@ -1366,7 +1389,7 @@ namespace { // Try to reduce non-pv search depth by one ply if move seems not problematic, // if the move fails high will be re-searched at full depth. - if ( depth >= 2*OnePly + if ( depth >= 3*OnePly && moveCount >= LMRNonPVMoves && !dangerous && !moveIsCapture @@ -1431,7 +1454,7 @@ namespace { Move m = ss[ply].pv[ply]; if (ok_to_history(pos, m)) // Only non capture moves are considered { - update_history(pos, m, depth, Threads[threadID].H, movesSearched, moveCount); + update_history(pos, m, depth, movesSearched, moveCount); update_killers(m, ss[ply]); } TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, depth, m); @@ -1491,10 +1514,9 @@ namespace { if (isCheck) staticValue = -VALUE_INFINITE; - else if (tte && tte->type() == VALUE_TYPE_EVAL) + else if (tte && (tte->type() & VALUE_TYPE_EVAL)) { // Use the cached evaluation score if possible - assert(tte->value() == evaluate(pos, ei, threadID)); assert(ei.futilityMargin == Value(0)); staticValue = tte->value(); @@ -1513,7 +1535,7 @@ namespace { { // Store the score to avoid a future costly evaluation() call if (!isCheck && !tte && ei.futilityMargin == 0) - TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_EVAL, Depth(-127*OnePly), MOVE_NONE); + TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_EV_LO, Depth(-127*OnePly), MOVE_NONE); return bestValue; } @@ -1524,7 +1546,7 @@ namespace { // Initialize a MovePicker object for the current position, and prepare // to search the moves. Because the depth is <= 0 here, only captures, // queen promotions and checks (only if depth == 0) will be generated. - MovePicker mp = MovePicker(pos, ttMove, depth, Threads[threadID].H); + MovePicker mp = MovePicker(pos, ttMove, depth, H); Move move; int moveCount = 0; Bitboard dcCandidates = mp.discovered_check_candidates(); @@ -1567,9 +1589,7 @@ namespace { // Don't search captures and checks with negative SEE values if ( !isCheck && !move_is_promotion(move) - && (pos.midgame_value_of_piece_on(move_from(move)) > - pos.midgame_value_of_piece_on(move_to(move))) - && pos.see(move) < 0) + && pos.see_sign(move) < 0) continue; // Make and search the move. @@ -1603,9 +1623,13 @@ namespace { Move m = ss[ply].pv[ply]; if (!pvNode) { + // If bestValue isn't changed it means it is still the static evaluation of + // the node, so keep this info to avoid a future costly evaluation() call. + ValueType type = (bestValue == staticValue && !ei.futilityMargin ? VALUE_TYPE_EV_UP : VALUE_TYPE_UPPER); Depth d = (depth == Depth(0) ? Depth(0) : Depth(-1)); + if (bestValue < beta) - TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_UPPER, d, MOVE_NONE); + TT.store(pos.get_key(), value_to_tt(bestValue, ply), type, d, MOVE_NONE); else TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, d, m); } @@ -1665,7 +1689,7 @@ namespace { && !moveIsCapture && !move_is_promotion(move) && moveCount >= 2 + int(sp->depth) - && ok_to_prune(pos, move, ss[sp->ply].threatMove, sp->depth, Threads[threadID].H)) + && ok_to_prune(pos, move, ss[sp->ply].threatMove, sp->depth)) continue; // Make and search the move. @@ -1921,15 +1945,15 @@ namespace { bool includeAllMoves = (searchMoves[0] == MOVE_NONE); // Generate all legal moves - int lm_count = generate_legal_moves(pos, mlist); + MoveStack* last = generate_moves(pos, mlist); // Add each move to the moves[] array - for (int i = 0; i < lm_count; i++) + for (MoveStack* cur = mlist; cur != last; cur++) { bool includeMove = includeAllMoves; for (int k = 0; !includeMove && searchMoves[k] != MOVE_NONE; k++) - includeMove = (searchMoves[k] == mlist[i].move); + includeMove = (searchMoves[k] == cur->move); if (!includeMove) continue; @@ -1938,7 +1962,7 @@ namespace { StateInfo st; SearchStack ss[PLY_MAX_PLUS_2]; - moves[count].move = mlist[i].move; + moves[count].move = cur->move; pos.do_move(moves[count].move, st); moves[count].score = -qsearch(pos, ss, -VALUE_INFINITE, VALUE_INFINITE, Depth(0), 1, 0); pos.undo_move(moves[count].move); @@ -2109,7 +2133,9 @@ namespace { // the second move is assumed to be a move from the current position. bool connected_moves(const Position& pos, Move m1, Move m2) { + Square f1, t1, f2, t2; + Piece p; assert(move_is_ok(m1)); assert(move_is_ok(m2)); @@ -2135,31 +2161,32 @@ namespace { return true; // Case 4: The destination square for m2 is attacked by the moving piece in m1 - if (pos.piece_attacks_square(pos.piece_on(t1), t1, t2)) + p = pos.piece_on(t1); + if (bit_is_set(pos.attacks_from(p, t1), t2)) return true; // Case 5: Discovered check, checking piece is the piece moved in m1 - if ( piece_is_slider(pos.piece_on(t1)) + if ( piece_is_slider(p) && bit_is_set(squares_between(t1, pos.king_square(pos.side_to_move())), f2) - && !bit_is_set(squares_between(t2, pos.king_square(pos.side_to_move())), t2)) + && !bit_is_set(squares_between(t1, pos.king_square(pos.side_to_move())), t2)) { Bitboard occ = pos.occupied_squares(); Color us = pos.side_to_move(); Square ksq = pos.king_square(us); clear_bit(&occ, f2); - if (pos.type_of_piece_on(t1) == BISHOP) + if (type_of_piece(p) == BISHOP) { if (bit_is_set(bishop_attacks_bb(ksq, occ), t1)) return true; } - else if (pos.type_of_piece_on(t1) == ROOK) + else if (type_of_piece(p) == ROOK) { if (bit_is_set(rook_attacks_bb(ksq, occ), t1)) return true; } else { - assert(pos.type_of_piece_on(t1) == QUEEN); + assert(type_of_piece(p) == QUEEN); if (bit_is_set(queen_attacks_bb(ksq, occ), t1)) return true; } @@ -2207,25 +2234,29 @@ namespace { assert(m != MOVE_NONE); Depth result = Depth(0); - *dangerous = check || singleReply || mateThreat; + *dangerous = check | singleReply | mateThreat; - if (check) - result += CheckExtension[pvNode]; + if (*dangerous) + { + if (check) + result += CheckExtension[pvNode]; - if (singleReply) - result += SingleReplyExtension[pvNode]; + if (singleReply) + result += SingleReplyExtension[pvNode]; - if (mateThreat) - result += MateThreatExtension[pvNode]; + if (mateThreat) + result += MateThreatExtension[pvNode]; + } if (pos.type_of_piece_on(move_from(m)) == PAWN) { - if (pos.move_is_pawn_push_to_7th(m)) + Color c = pos.side_to_move(); + if (relative_rank(c, move_to(m)) == RANK_7) { result += PawnPushTo7thExtension[pvNode]; *dangerous = true; } - if (pos.move_is_passed_pawn_push(m)) + if (pos.pawn_is_passed(c, move_to(m))) { result += PassedPawnExtension[pvNode]; *dangerous = true; @@ -2246,7 +2277,7 @@ namespace { if ( pvNode && capture && pos.type_of_piece_on(move_to(m)) != PAWN - && pos.see(m) >= 0) + && pos.see_sign(m) >= 0) { result += OnePly/2; *dangerous = true; @@ -2274,7 +2305,7 @@ namespace { // non-tactical moves late in the move list close to the leaves are // candidates for pruning. - bool ok_to_prune(const Position& pos, Move m, Move threat, Depth d, const History& H) { + bool ok_to_prune(const Position& pos, Move m, Move threat, Depth d) { assert(move_is_ok(m)); assert(threat == MOVE_NONE || move_is_ok(threat)); @@ -2319,7 +2350,7 @@ namespace { && threat != MOVE_NONE && piece_is_slider(pos.piece_on(tfrom)) && bit_is_set(squares_between(tfrom, tto), mto) - && pos.see(m) >= 0) + && pos.see_sign(m) >= 0) return false; return true; @@ -2354,7 +2385,7 @@ namespace { // update_history() registers a good move that produced a beta-cutoff // in history and marks as failures all the other moves of that ply. - void update_history(const Position& pos, Move m, Depth depth, History& H, + void update_history(const Position& pos, Move m, Depth depth, Move movesSearched[], int moveCount) { H.success(pos.piece_on(move_from(m)), move_to(m), depth); @@ -2382,6 +2413,7 @@ namespace { ss.killers[0] = m; } + // fail_high_ply_1() checks if some thread is currently resolving a fail // high at ply 1 at the node below the first root node. This information // is used for time managment.