X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fsearch.cpp;h=982f2a2cd279e26273476d955d75e2305857eef2;hb=4270aec55886f56d1d588ea329bb5a1c50998c19;hp=f35f6b6cf91293bb5b43c1d8ef58df75bf7f8211;hpb=204efb109bf125e1fdbc8dbb011c13a8e5aa9e8c;p=stockfish diff --git a/src/search.cpp b/src/search.cpp index f35f6b6c..982f2a2c 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -298,7 +298,6 @@ namespace { void update_history(const Position& pos, Move move, Depth depth, Move movesSearched[], int moveCount); void update_killers(Move m, Move killers[]); void update_gains(const Position& pos, Move move, Value before, Value after); - void qsearch_scoring(Position& pos, MoveStack* mlist, MoveStack* last); int current_search_time(); std::string value_to_uci(Value v); @@ -579,8 +578,15 @@ bool think(Position& pos, bool infinite, bool ponder, int time[], int increment[ if (!StopRequest && (Pondering || InfiniteSearch)) wait_for_stop_or_ponderhit(); - // Could be both MOVE_NONE when searching on a stalemate position - cout << "bestmove " << bestMove << " ponder " << ponderMove << endl; + // Could be MOVE_NONE when searching on a stalemate position + cout << "bestmove " << bestMove; + + // UCI protol is not clear on allowing sending an empty ponder move, instead + // it is clear that ponder move is optional. So skip it if empty. + if (ponderMove != MOVE_NONE) + cout << " ponder " << ponderMove; + + cout << endl; return !QuitRequest; } @@ -597,21 +603,21 @@ namespace { SearchStack ss[PLY_MAX_PLUS_2]; Value bestValues[PLY_MAX_PLUS_2]; int bestMoveChanges[PLY_MAX_PLUS_2]; - int depth, researchCountFL, researchCountFH, aspirationDelta; + int depth, aspirationDelta; Value value, alpha, beta; Move bestMove, easyMove; - // Moves to search are verified, scored and sorted - Rml.init(pos, searchMoves); - - // Initialize FIXME move before Rml.init() + // Initialize stuff before a new search + memset(ss, 0, 4 * sizeof(SearchStack)); TT.new_search(); H.clear(); - memset(ss, 0, 4 * sizeof(SearchStack)); *ponderMove = bestMove = easyMove = MOVE_NONE; depth = aspirationDelta = 0; - ss->currentMove = MOVE_NULL; // Hack to skip update_gains() 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) @@ -623,16 +629,11 @@ namespace { return MOVE_NONE; } - // 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].pv[0]; - // Iterative deepening loop while (++depth <= PLY_MAX && (!MaxDepth || depth <= MaxDepth) && !StopRequest) { - Rml.bestMoveChanges = researchCountFL = researchCountFH = 0; - cout << "info depth " << depth << endl; + 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) @@ -649,19 +650,14 @@ namespace { // Start with a small aspiration window and, in case of fail high/low, // research with bigger window until not failing high/low anymore. - while (true) - { + do { // Search starting from ss+1 to allow calling update_gains() value = search(pos, ss+1, alpha, beta, depth * ONE_PLY, 0); - // Send PV line to GUI and write to transposition table in case the - // relevant entries have been overwritten during the search. + // 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); - cout << set960(pos.is_chess960()) - << Rml[i].pv_info_to_uci(pos, depth, alpha, beta, i) << endl; - } // Value cannot be trusted. Break out immediately! if (StopRequest) @@ -673,31 +669,38 @@ namespace { // otherwise exit the fail high/low loop. if (value >= beta) { - beta = Min(beta + aspirationDelta * (1 << researchCountFH), VALUE_INFINITE); - researchCountFH++; + beta = Min(beta + aspirationDelta, VALUE_INFINITE); + aspirationDelta += aspirationDelta / 2; } else if (value <= alpha) { AspirationFailLow = true; StopOnPonderhit = false; - alpha = Max(alpha - aspirationDelta * (1 << researchCountFL), -VALUE_INFINITE); - researchCountFL++; + 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]; bestValues[depth] = value; bestMoveChanges[depth] = Rml.bestMoveChanges; + // Send PV line to GUI and to log file + for (int i = 0; i < Min(MultiPV, (int)Rml.size()); i++) + cout << Rml[i].pv_info_to_uci(pos, depth, alpha, beta, i) << endl; + if (UseLogFile) LogFile << pretty_pv(pos, depth, value, current_search_time(), Rml[0].pv) << endl; - // Drop the easy move if differs from the new best move - if (bestMove != easyMove) + // 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)) + easyMove = bestMove; + else if (bestMove != easyMove) easyMove = MOVE_NONE; if (UseTimeManagement && !StopRequest) @@ -1032,7 +1035,9 @@ split_point_start: // At split points actual search starts from here << " currmovenumber " << moveCount << endl; } - isPvMove = (PvNode && moveCount <= (Root ? MultiPV : 1)); + // At Root and at first iteration do a PV search on all the moves + // to score root moves. Otherwise only the first one is the PV. + isPvMove = (PvNode && moveCount <= (Root ? MultiPV + 1000 * (depth <= ONE_PLY) : 1)); moveIsCheck = pos.move_is_check(move, ci); captureOrPromotion = pos.move_is_capture_or_promotion(move); @@ -1501,26 +1506,6 @@ split_point_start: // At split points actual search starts from here } - // qsearch_scoring() scores each move of a list using a qsearch() evaluation, - // it is used in RootMoveList to get an initial scoring. - void qsearch_scoring(Position& pos, MoveStack* mlist, MoveStack* last) { - - SearchStack ss[PLY_MAX_PLUS_2]; - StateInfo st; - - memset(ss, 0, 4 * sizeof(SearchStack)); - ss[0].eval = ss[0].evalMargin = VALUE_NONE; - - for (MoveStack* cur = mlist; cur != last; cur++) - { - ss[0].currentMove = cur->move; - pos.do_move(cur->move, st); - cur->score = -qsearch(pos, ss+1, -VALUE_INFINITE, VALUE_INFINITE, DEPTH_ZERO, 1); - pos.undo_move(cur->move); - } - } - - // check_is_dangerous() tests if a checking move can be pruned in qsearch(). // bestValue is updated only when returning false because in that case move // will be pruned. @@ -2559,11 +2544,8 @@ split_point_start: // At split points actual search starts from here clear(); bestMoveChanges = 0; - // Generate all legal moves and score them + // Generate all legal moves and add them to RootMoveList MoveStack* last = generate(pos, mlist); - qsearch_scoring(pos, mlist, last); - - // Add each move to the RootMoveList's vector for (MoveStack* cur = mlist; cur != last; cur++) { // If we have a searchMoves[] list then verify cur->move @@ -2576,10 +2558,9 @@ split_point_start: // At split points actual search starts from here RootMove rm; rm.pv[0] = cur->move; rm.pv[1] = MOVE_NONE; - rm.pv_score = Value(cur->score); + rm.pv_score = -VALUE_INFINITE; push_back(rm); } - sort(); } } // namespace