X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fsearch.cpp;h=1b98627e9bf1749e6e5ebb04370fdd09539c0016;hb=3835f49aa10af094642d94b1765183c8bffd561b;hp=95a516d70e9a58a5bf3592cadf7826b417af2519;hpb=3346ccc9d965e13689ff4af12b2ea2433651890a;p=stockfish diff --git a/src/search.cpp b/src/search.cpp index 95a516d7..1b98627e 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -124,39 +124,19 @@ namespace { // 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; + : non_pv_score < m.non_pv_score; } - void set_pv(const Move newPv[]); + + void extract_pv_from_tt(Position& pos); + void insert_pv_in_tt(Position& pos); + std::string pv_info_to_uci(const Position& pos, Value alpha, Value beta, int pvLine = 0); int64_t nodes; - Value pv_score, non_pv_score; - Move move, pv[PLY_MAX_PLUS_2]; + Value pv_score; + Value non_pv_score; + Move pv[PLY_MAX_PLUS_2]; }; - RootMove::RootMove() : nodes(0) { - - pv_score = non_pv_score = -VALUE_INFINITE; - move = pv[0] = MOVE_NONE; - } - - RootMove& RootMove::operator=(const RootMove& rm) { - - pv_score = rm.pv_score; non_pv_score = rm.non_pv_score; - nodes = rm.nodes; move = rm.move; - set_pv(rm.pv); // Skip costly full pv[] copy - return *this; - } - - void RootMove::set_pv(const Move newPv[]) { - - Move* p = pv; - - while (*newPv != MOVE_NONE) - *p++ = *newPv++; - - *p = MOVE_NONE; - } - // RootMoveList struct is essentially a std::vector<> of RootMove objects, // with an handful of methods above the standard ones. @@ -295,8 +275,8 @@ namespace { /// Local functions - Value id_loop(Position& pos, Move searchMoves[]); - Value root_search(Position& pos, SearchStack* ss, Move* pv, RootMoveList& rml, Value* alphaPtr, Value* betaPtr); + Move id_loop(Position& pos, Move searchMoves[], Move* ponderMove); + Value root_search(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, RootMoveList& rml); template Value search(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, int ply); @@ -333,9 +313,6 @@ namespace { void ponderhit(); void wait_for_stop_or_ponderhit(); void init_ss_array(SearchStack* ss, int size); - void print_pv_info(const Position& pos, Move pv[], Value alpha, Value beta, Value value); - void insert_pv_in_tt(const Position& pos, Move pv[]); - void extract_pv_from_tt(const Position& pos, Move bestMove, Move pv[]); #if !defined(_MSC_VER) void* init_thread(void* threadID); @@ -514,7 +491,32 @@ bool think(Position& pos, bool infinite, bool ponder, int time[], int increment[ << " moves to go: " << movesToGo << endl; // We're ready to start thinking. Call the iterative deepening loop function - id_loop(pos, searchMoves); + Move ponderMove = MOVE_NONE; + Move bestMove = id_loop(pos, searchMoves, &ponderMove); + + // Print final search statistics + cout << "info nodes " << pos.nodes_searched() + << " nps " << nps(pos) + << " time " << current_search_time() << endl; + + if (UseLogFile) + { + if (dbg_show_mean) + dbg_print_mean(LogFile); + + if (dbg_show_hit_rate) + dbg_print_hit_rate(LogFile); + + LogFile << "\nNodes: " << pos.nodes_searched() + << "\nNodes/second: " << nps(pos) + << "\nBest move: " << move_to_san(pos, bestMove); + + StateInfo st; + pos.do_move(bestMove, st); + LogFile << "\nPonder move: " + << move_to_san(pos, ponderMove) // Works also with MOVE_NONE + << endl; + } if (UseLogFile) LogFile.close(); @@ -522,6 +524,14 @@ bool think(Position& pos, bool infinite, bool ponder, int time[], int increment[ // This makes all the threads to go to sleep ThreadsMgr.set_active_threads(1); + // If we are pondering or in infinite search, we shouldn't print the + // best move before we are told to do so. + if (!AbortSearch && (PonderSearch || InfiniteSearch)) + wait_for_stop_or_ponderhit(); + + // Could be both MOVE_NONE when searching on a stalemate position + cout << "bestmove " << bestMove << " ponder " << ponderMove << endl; + return !Quit; } @@ -533,48 +543,43 @@ namespace { // been consumed, the user stops the search, or the maximum search depth is // reached. - Value id_loop(Position& pos, Move searchMoves[]) { + Move id_loop(Position& pos, Move searchMoves[], Move* ponderMove) { SearchStack ss[PLY_MAX_PLUS_2]; - Move pv[PLY_MAX_PLUS_2]; + Depth depth; Move EasyMove = MOVE_NONE; Value value, alpha = -VALUE_INFINITE, beta = VALUE_INFINITE; - // Moves to search are verified, copied, scored and sorted + // Moves to search are verified, scored and sorted RootMoveList rml(pos, searchMoves); // Handle special case of searching on a mate/stale position if (rml.size() == 0) { - if (PonderSearch) - wait_for_stop_or_ponderhit(); + Value s = (pos.is_check() ? -VALUE_MATE : VALUE_DRAW); - return pos.is_check() ? -VALUE_MATE : VALUE_DRAW; - } + cout << "info depth " << 1 + << " score " << value_to_uci(s) << endl; - // Print RootMoveList startup scoring to the standard output, - // so to output information also for iteration 1. - cout << set960(pos.is_chess960()) // Is enough to set once at the beginning - << "info depth " << 1 - << "\ninfo depth " << 1 - << " score " << value_to_uci(rml[0].pv_score) - << " time " << current_search_time() - << " nodes " << pos.nodes_searched() - << " nps " << nps(pos) - << " pv " << rml[0].move << "\n"; + return MOVE_NONE; + } // Initialize TT.new_search(); H.clear(); init_ss_array(ss, PLY_MAX_PLUS_2); - pv[0] = pv[1] = MOVE_NONE; ValueByIteration[1] = rml[0].pv_score; Iteration = 1; + // Send initial RootMoveList scoring (iteration 1) + cout << set960(pos.is_chess960()) // Is enough to set once at the beginning + << "info depth " << Iteration + << "\n" << rml[0].pv_info_to_uci(pos, alpha, beta) << endl; + // Is one move significantly better than others after initial scoring ? if ( rml.size() == 1 || rml[0].pv_score > rml[1].pv_score + EasyMoveMargin) - EasyMove = rml[0].move; + EasyMove = rml[0].pv[0]; // Iterative deepening loop while (Iteration < PLY_MAX) @@ -598,12 +603,10 @@ namespace { beta = Min(ValueByIteration[Iteration - 1] + AspirationDelta, VALUE_INFINITE); } - // Search to the current depth, rml is updated and sorted, alpha and beta could change - value = root_search(pos, ss, pv, rml, &alpha, &beta); + depth = (Iteration - 2) * ONE_PLY + InitialDepth; - // Write PV to transposition table, in case the relevant entries have - // been overwritten during the search. - insert_pv_in_tt(pos, pv); + // Search to the current depth, rml is updated and sorted + value = root_search(pos, ss, alpha, beta, depth, rml); if (AbortSearch) break; // Value cannot be trusted. Break out immediately! @@ -612,7 +615,7 @@ namespace { ValueByIteration[Iteration] = value; // Drop the easy move if differs from the new best move - if (pv[0] != EasyMove) + if (rml[0].pv[0] != EasyMove) EasyMove = MOVE_NONE; if (UseTimeManagement) @@ -633,7 +636,7 @@ namespace { // Stop search early if one move seems to be much better than the others if ( Iteration >= 8 - && EasyMove == pv[0] + && EasyMove == rml[0].pv[0] && ( ( rml[0].nodes > (pos.nodes_searched() * 85) / 100 && current_search_time() > TimeMgr.available_time() / 16) ||( rml[0].nodes > (pos.nodes_searched() * 98) / 100 @@ -664,75 +667,29 @@ namespace { break; } - // If we are pondering or in infinite search, we shouldn't print the - // best move before we are told to do so. - if (!AbortSearch && (PonderSearch || InfiniteSearch)) - wait_for_stop_or_ponderhit(); - else - // Print final search statistics - cout << "info nodes " << pos.nodes_searched() - << " nps " << nps(pos) - << " time " << current_search_time() << endl; - - // Print the best move and the ponder move to the standard output - if (pv[0] == MOVE_NONE || MultiPV > 1) - { - pv[0] = rml[0].move; - pv[1] = MOVE_NONE; - } - - assert(pv[0] != MOVE_NONE); - - cout << "bestmove " << pv[0]; - - if (pv[1] != MOVE_NONE) - cout << " ponder " << pv[1]; - - cout << endl; - - if (UseLogFile) - { - if (dbg_show_mean) - dbg_print_mean(LogFile); - - if (dbg_show_hit_rate) - dbg_print_hit_rate(LogFile); - - LogFile << "\nNodes: " << pos.nodes_searched() - << "\nNodes/second: " << nps(pos) - << "\nBest move: " << move_to_san(pos, pv[0]); - - StateInfo st; - pos.do_move(pv[0], st); - LogFile << "\nPonder move: " - << move_to_san(pos, pv[1]) // Works also with MOVE_NONE - << endl; - } - return rml[0].pv_score; + *ponderMove = rml[0].pv[1]; + return rml[0].pv[0]; } // root_search() is the function which searches the root node. It is - // similar to search_pv except that it uses a different move ordering - // scheme, prints some information to the standard output and handles - // the fail low/high loops. - - Value root_search(Position& pos, SearchStack* ss, Move* pv, RootMoveList& rml, Value* alphaPtr, Value* betaPtr) { + // similar to search_pv except that it prints some information to the + // standard output and handles the fail low/high loops. + Value root_search(Position& pos, SearchStack* ss, Value alpha, + Value beta, Depth depth, RootMoveList& rml) { StateInfo st; CheckInfo ci(pos); int64_t nodes; Move move; - Depth depth, ext, newDepth; - Value value, alpha, beta; + Depth ext, newDepth; + Value value, oldAlpha; bool isCheck, moveIsCheck, captureOrPromotion, dangerous; int researchCountFH, researchCountFL; researchCountFH = researchCountFL = 0; - alpha = *alphaPtr; - beta = *betaPtr; + oldAlpha = alpha; isCheck = pos.is_check(); - depth = (Iteration - 2) * ONE_PLY + InitialDepth; // Step 1. Initialize node (polling is omitted at root) ss->currentMove = ss->bestMove = MOVE_NONE; @@ -771,7 +728,7 @@ namespace { // Pick the next root move, and print the move and the move number to // the standard output. - move = ss->currentMove = rml[i].move; + move = ss->currentMove = rml[i].pv[0]; if (current_search_time() >= 1000) cout << "info currmove " << move @@ -853,16 +810,15 @@ namespace { // We are failing high and going to do a research. It's important to update // the score before research in case we run out of time while researching. - rml[i].pv_score = value; ss->bestMove = move; - extract_pv_from_tt(pos, move, pv); - rml[i].set_pv(pv); + rml[i].pv_score = value; + rml[i].extract_pv_from_tt(pos); - // Print information to the standard output - print_pv_info(pos, pv, alpha, beta, value); + // Inform GUI that PV has changed + cout << rml[i].pv_info_to_uci(pos, alpha, beta) << endl; // Prepare for a research after a fail high, each time with a wider window - *betaPtr = beta = Min(beta + AspirationDelta * (1 << researchCountFH), VALUE_INFINITE); + beta = Min(beta + AspirationDelta * (1 << researchCountFH), VALUE_INFINITE); researchCountFH++; } // End of fail high loop @@ -889,62 +845,50 @@ namespace { // PV move or new best move! // Update PV - rml[i].pv_score = value; ss->bestMove = move; - extract_pv_from_tt(pos, move, pv); - rml[i].set_pv(pv); + rml[i].pv_score = value; + rml[i].extract_pv_from_tt(pos); - if (MultiPV == 1) - { - // We record how often the best move has been changed in each - // iteration. This information is used for time managment: When - // the best move changes frequently, we allocate some more time. - if (i > 0) - BestMoveChangesByIteration[Iteration]++; + // We record how often the best move has been changed in each + // iteration. This information is used for time managment: When + // the best move changes frequently, we allocate some more time. + if (MultiPV == 1 && i > 0) + BestMoveChangesByIteration[Iteration]++; + + // Inform GUI that PV has changed, in case of multi-pv UCI protocol + // requires we send all the PV lines properly sorted. + rml.sort_multipv(i); - // Print information to the standard output - print_pv_info(pos, pv, alpha, beta, value); + for (int j = 0; j < Min(MultiPV, (int)rml.size()); j++) + cout << rml[j].pv_info_to_uci(pos, alpha, beta, j) << endl; + // Update alpha. In multi-pv we don't use aspiration window + if (MultiPV == 1) + { // Raise alpha to setup proper non-pv search upper bound if (value > alpha) alpha = value; } - else // MultiPV > 1 - { - rml.sort_multipv(i); - for (int j = 0; j < Min(MultiPV, (int)rml.size()); j++) - { - cout << "info multipv " << j + 1 - << " score " << value_to_uci(rml[j].pv_score) - << " depth " << (j <= i ? Iteration : Iteration - 1) - << " time " << current_search_time() - << " nodes " << pos.nodes_searched() - << " nps " << nps(pos) - << " pv "; - - for (int k = 0; rml[j].pv[k] != MOVE_NONE && k < PLY_MAX; k++) - cout << rml[j].pv[k] << " "; - - cout << endl; - } + else // Set alpha equal to minimum score among the PV lines alpha = rml[Min(i, MultiPV - 1)].pv_score; - } + } // PV move or new best move - assert(alpha >= *alphaPtr); + assert(alpha >= oldAlpha); - AspirationFailLow = (alpha == *alphaPtr); + AspirationFailLow = (alpha == oldAlpha); if (AspirationFailLow && StopOnPonderhit) StopOnPonderhit = false; - } + + } // Root moves loop // Can we exit fail low loop ? if (AbortSearch || !AspirationFailLow) break; // Prepare for a research after a fail low, each time with a wider window - *alphaPtr = alpha = Max(alpha - AspirationDelta * (1 << researchCountFL), -VALUE_INFINITE); + oldAlpha = alpha = Max(alpha - AspirationDelta * (1 << researchCountFL), -VALUE_INFINITE); researchCountFL++; } // Fail low loop @@ -952,6 +896,11 @@ namespace { // Sort the moves before to return rml.sort(); + // Write PV lines to transposition table, in case the relevant entries + // have been overwritten during the search. + for (int i = 0; i < MultiPV; i++) + rml[i].insert_pv_in_tt(pos); + return alpha; } @@ -1982,14 +1931,19 @@ 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 protocol + // value_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) { std::stringstream s; if (abs(v) < VALUE_MATE - PLY_MAX * ONE_PLY) - s << "cp " << int(v) * 100 / int(PawnValueMidgame); // Scale to pawn = 100 + s << "cp " << int(v) * 100 / int(PawnValueMidgame); // Scale to centipawns else s << "mate " << (v > 0 ? (VALUE_MATE - v + 1) / 2 : -(VALUE_MATE + v) / 2 ); @@ -2146,88 +2100,6 @@ split_point_start: // At split points actual search starts from here } - // print_pv_info() prints to standard output and eventually to log file information on - // the current PV line. It is called at each iteration or after a new pv is found. - - void print_pv_info(const Position& pos, Move pv[], Value alpha, Value beta, Value value) { - - cout << "info depth " << Iteration - << " score " << value_to_uci(value) - << (value >= beta ? " lowerbound" : value <= alpha ? " upperbound" : "") - << " time " << current_search_time() - << " nodes " << pos.nodes_searched() - << " nps " << nps(pos) - << " pv "; - - for (Move* m = pv; *m != MOVE_NONE; m++) - cout << *m << " "; - - cout << endl; - - if (UseLogFile) - { - ValueType t = value >= beta ? VALUE_TYPE_LOWER : - value <= alpha ? VALUE_TYPE_UPPER : VALUE_TYPE_EXACT; - - LogFile << pretty_pv(pos, current_search_time(), Iteration, value, t, pv) << endl; - } - } - - - // insert_pv_in_tt() is called at the end of a search iteration, and inserts - // the PV back into the TT. This makes sure the old PV moves are searched - // first, even if the old TT entries have been overwritten. - - void insert_pv_in_tt(const Position& pos, Move pv[]) { - - StateInfo st; - TTEntry* tte; - Position p(pos, pos.thread()); - Value v, m = VALUE_NONE; - - for (int i = 0; pv[i] != MOVE_NONE; i++) - { - tte = TT.retrieve(p.get_key()); - if (!tte || tte->move() != pv[i]) - { - v = (p.is_check() ? VALUE_NONE : evaluate(p, m)); - TT.store(p.get_key(), VALUE_NONE, VALUE_TYPE_NONE, DEPTH_NONE, pv[i], v, m); - } - p.do_move(pv[i], st); - } - } - - - // 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 - // long PV to print that is important for position analysis. - - void extract_pv_from_tt(const Position& pos, Move bestMove, Move pv[]) { - - StateInfo st; - TTEntry* tte; - Position p(pos, pos.thread()); - int ply = 0; - - assert(bestMove != MOVE_NONE); - - pv[ply] = bestMove; - p.do_move(pv[ply++], st); - - while ( (tte = TT.retrieve(p.get_key())) != NULL - && tte->move() != MOVE_NONE - && move_is_legal(p, tte->move()) - && ply < PLY_MAX - && (!p.is_draw() || ply < 2)) - { - pv[ply] = tte->move(); - p.do_move(pv[ply++], st); - } - pv[ply] = MOVE_NONE; - } - - // init_thread() is the function which is called when a new thread is // launched. It simply calls the idle_loop() function with the supplied // threadID. There are two versions of this function; one for POSIX @@ -2655,16 +2527,126 @@ split_point_start: // At split points actual search starts from here } - /// The RootMoveList class + /// 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; + } + + // 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 + // long PV to print that is important for position analysis. + + void RootMove::extract_pv_from_tt(Position& pos) { + + StateInfo state[PLY_MAX_PLUS_2], *st = state; + TTEntry* tte; + int ply = 1; + + assert(pv[0] != MOVE_NONE && move_is_legal(pos, pv[0])); + + pos.do_move(pv[0], *st++); + + while ( (tte = TT.retrieve(pos.get_key())) != NULL + && tte->move() != MOVE_NONE + && move_is_legal(pos, tte->move()) + && ply < PLY_MAX + && (!pos.is_draw() || ply < 2)) + { + pv[ply] = tte->move(); + pos.do_move(pv[ply++], *st++); + } + pv[ply] = MOVE_NONE; + + do pos.undo_move(pv[--ply]); while (ply); + } + + // insert_pv_in_tt() is called at the end of a search iteration, and inserts + // the PV back into the TT. This makes sure the old PV moves are searched + // first, even if the old TT entries have been overwritten. + + void RootMove::insert_pv_in_tt(Position& pos) { + + StateInfo state[PLY_MAX_PLUS_2], *st = state; + TTEntry* tte; + Key k; + Value v, m = VALUE_NONE; + int ply = 0; + + assert(pv[0] != MOVE_NONE && move_is_legal(pos, pv[0])); + + do { + k = pos.get_key(); + tte = TT.retrieve(k); + + // Don't overwrite exsisting correct entries + if (!tte || tte->move() != pv[ply]) + { + v = (pos.is_check() ? VALUE_NONE : evaluate(pos, m)); + TT.store(k, VALUE_NONE, VALUE_TYPE_NONE, DEPTH_NONE, pv[ply], v, m); + } + pos.do_move(pv[ply], *st++); + + } while (pv[++ply] != MOVE_NONE); + + 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 and eventually writes the info + // to a log file. It is called at each iteration or after a new pv is found. + + std::string RootMove::pv_info_to_uci(const Position& pos, Value alpha, Value beta, int pvLine) { + + std::stringstream s; + + s << "info depth " << Iteration // FIXME + << " multipv " << pvLine + 1 + << " score " << value_to_uci(pv_score) + << (pv_score >= beta ? " lowerbound" : pv_score <= alpha ? " upperbound" : "") + << " time " << current_search_time() + << " nodes " << pos.nodes_searched() + << " nps " << nps(pos) + << " pv "; + + for (Move* m = pv; *m != MOVE_NONE; m++) + s << *m << " "; + + if (UseLogFile && pvLine == 0) + { + ValueType t = pv_score >= beta ? VALUE_TYPE_LOWER : + pv_score <= alpha ? VALUE_TYPE_UPPER : VALUE_TYPE_EXACT; + + LogFile << pretty_pv(pos, current_search_time(), Iteration, pv_score, t, pv) << endl; + } + return s.str(); + } - // RootMoveList c'tor RootMoveList::RootMoveList(Position& pos, Move searchMoves[]) { SearchStack ss[PLY_MAX_PLUS_2]; MoveStack mlist[MOVES_MAX]; StateInfo st; - bool includeAllMoves = (searchMoves[0] == MOVE_NONE); + Move* sm; // Initialize search stack init_ss_array(ss, PLY_MAX_PLUS_2); @@ -2673,25 +2655,26 @@ split_point_start: // At split points actual search starts from here // Generate all legal moves MoveStack* last = generate_moves(pos, mlist); - // Add each move to the moves[] array + // Add each move to the RootMoveList's vector for (MoveStack* cur = mlist; cur != last; cur++) { - bool includeMove = includeAllMoves; - - for (int k = 0; !includeMove && searchMoves[k] != MOVE_NONE; k++) - includeMove = (searchMoves[k] == cur->move); + // If we have a searchMoves[] list then verify cur->move + // is in the list before to add it. + for (sm = searchMoves; *sm && *sm != cur->move; sm++) {} - if (!includeMove) + if (searchMoves[0] && *sm != cur->move) continue; // Find a quick score for the move and add to the list + pos.do_move(cur->move, st); + RootMove rm; - rm.move = ss[0].currentMove = rm.pv[0] = cur->move; + rm.pv[0] = ss[0].currentMove = cur->move; rm.pv[1] = MOVE_NONE; - pos.do_move(cur->move, st); rm.pv_score = -qsearch(pos, ss+1, -VALUE_INFINITE, VALUE_INFINITE, DEPTH_ZERO, 1); - pos.undo_move(cur->move); push_back(rm); + + pos.undo_move(cur->move); } sort(); } @@ -2709,7 +2692,7 @@ split_point_start: // At split points actual search starts from here while ((move = mp.get_next_move()) != MOVE_NONE) for (Base::iterator it = begin(); it != end(); ++it) - if (it->move == move) + if (it->pv[0] == move) { it->non_pv_score = score--; break;