X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=fa7052d0dc0c2605201a17bd283742541e1c3c59;hp=588f76f3e6b789c6d8d500c56aba12eaf61718c7;hb=c295599e4ad481f677b14cb0be14174b61ebff81;hpb=9645e8e4e76aebc4b3099b20846c14e18768cab4 diff --git a/src/search.cpp b/src/search.cpp index 588f76f3..fa7052d0 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -38,6 +38,7 @@ #include "lock.h" #include "san.h" #include "search.h" +#include "timeman.h" #include "thread.h" #include "tt.h" #include "ucioption.h" @@ -250,10 +251,10 @@ namespace { int MultiPV; // Time managment variables - int SearchStartTime, MaxNodes, MaxDepth, MaxSearchTime; - int AbsoluteMaxSearchTime, ExtraSearchTime, ExactMaxTime; + int SearchStartTime, MaxNodes, MaxDepth, ExactMaxTime; bool UseTimeManagement, InfiniteSearch, PonderSearch, StopOnPonderhit; bool FirstRootMove, AbortSearch, Quit, AspirationFailLow; + TimeManager TimeMgr; // Log file bool UseLogFile; @@ -400,7 +401,6 @@ bool think(const Position& pos, bool infinite, bool ponder, int time[], int incr // Initialize global search variables StopOnPonderhit = AbortSearch = Quit = AspirationFailLow = false; - MaxSearchTime = AbsoluteMaxSearchTime = ExtraSearchTime = 0; NodesSincePoll = 0; TM.resetNodeCounters(); SearchStartTime = get_system_time(); @@ -472,40 +472,7 @@ bool think(const Position& pos, bool infinite, bool ponder, int time[], int incr int myTime = time[pos.side_to_move()]; int myIncrement = increment[pos.side_to_move()]; if (UseTimeManagement) - { - if (!movesToGo) // Sudden death time control - { - if (myIncrement) - { - MaxSearchTime = myTime / 30 + myIncrement; - AbsoluteMaxSearchTime = Max(myTime / 4, myIncrement - 100); - } - else // Blitz game without increment - { - MaxSearchTime = myTime / 30; - AbsoluteMaxSearchTime = myTime / 8; - } - } - else // (x moves) / (y minutes) - { - if (movesToGo == 1) - { - MaxSearchTime = myTime / 2; - AbsoluteMaxSearchTime = (myTime > 3000)? (myTime - 500) : ((myTime * 3) / 4); - } - else - { - MaxSearchTime = myTime / Min(movesToGo, 20); - AbsoluteMaxSearchTime = Min((4 * myTime) / movesToGo, myTime / 3); - } - } - - if (get_option_value_bool("Ponder")) - { - MaxSearchTime += MaxSearchTime / 4; - MaxSearchTime = Min(MaxSearchTime, AbsoluteMaxSearchTime); - } - } + TimeMgr.update(myTime, myIncrement, movesToGo, pos.startpos_ply_counter()); // Set best NodesBetweenPolls interval to avoid lagging under // heavy time pressure. @@ -649,20 +616,20 @@ namespace { if ( Iteration >= 8 && EasyMove == pv[0] && ( ( rml.get_move_cumulative_nodes(0) > (nodes * 85) / 100 - && current_search_time() > MaxSearchTime / 16) + && current_search_time() > TimeMgr.optimumSearchTime / 16) ||( rml.get_move_cumulative_nodes(0) > (nodes * 98) / 100 - && current_search_time() > MaxSearchTime / 32))) + && current_search_time() > TimeMgr.optimumSearchTime / 32))) stopSearch = true; // Add some extra time if the best move has changed during the last two iterations if (Iteration > 5 && Iteration <= 50) - ExtraSearchTime = BestMoveChangesByIteration[Iteration] * (MaxSearchTime / 2) - + BestMoveChangesByIteration[Iteration-1] * (MaxSearchTime / 3); + TimeMgr.best_move_changes(BestMoveChangesByIteration[Iteration], + BestMoveChangesByIteration[Iteration-1]); // Stop search if most of MaxSearchTime is consumed at the end of the // iteration. We probably don't have enough time to search the first // move at the next iteration anyway. - if (current_search_time() > ((MaxSearchTime + ExtraSearchTime) * 80) / 128) + if (current_search_time() > (TimeMgr.available_time() * 80) / 128) stopSearch = true; if (stopSearch) @@ -1002,7 +969,7 @@ namespace { Move movesSearched[256]; EvalInfo ei; StateInfo st; - const TTEntry* tte; + const TTEntry *tte, *ttx; Key posKey; Move ttMove, move, excludedMove, threatMove; Depth ext, newDepth; @@ -1062,32 +1029,31 @@ namespace { // Refresh tte entry to avoid aging TT.store(posKey, tte->value(), tte->type(), tte->depth(), ttMove, tte->static_value(), tte->king_danger()); - ss->currentMove = ttMove; // Can be MOVE_NONE + ss->bestMove = ttMove; // Can be MOVE_NONE return value_from_tt(tte->value(), ply); } - // Step 5. Evaluate the position statically - // At PV nodes we do this only to update gain statistics + // Step 5. Evaluate the position statically and + // update gain statistics of parent move. isCheck = pos.is_check(); - if (!isCheck) + if (isCheck) + ss->eval = VALUE_NONE; + else if (tte) { - if (tte) - { - assert(tte->static_value() != VALUE_NONE); - ss->eval = tte->static_value(); - ei.kingDanger[pos.side_to_move()] = tte->king_danger(); - } - else - { - ss->eval = evaluate(pos, ei); - TT.store(posKey, VALUE_NONE, VALUE_TYPE_NONE, DEPTH_NONE, MOVE_NONE, ss->eval, ei.kingDanger[pos.side_to_move()]); - } + assert(tte->static_value() != VALUE_NONE); - refinedValue = refine_eval(tte, ss->eval, ply); // Enhance accuracy with TT value if possible - update_gains(pos, (ss-1)->currentMove, (ss-1)->eval, ss->eval); + ss->eval = tte->static_value(); + ei.kingDanger[pos.side_to_move()] = tte->king_danger(); + refinedValue = refine_eval(tte, ss->eval, ply); } else - ss->eval = VALUE_NONE; + { + refinedValue = ss->eval = evaluate(pos, ei); + TT.store(posKey, VALUE_NONE, VALUE_TYPE_NONE, DEPTH_NONE, MOVE_NONE, ss->eval, ei.kingDanger[pos.side_to_move()]); + } + + // Save gain for the parent non-capture move + update_gains(pos, (ss-1)->currentMove, (ss-1)->eval, ss->eval); // Step 6. Razoring (is omitted in PV nodes) if ( !PvNode @@ -1113,8 +1079,8 @@ namespace { if ( !PvNode && !ss->skipNullMove && depth < RazorDepth - && refinedValue >= beta + futility_margin(depth, 0) && !isCheck + && refinedValue >= beta + futility_margin(depth, 0) && !value_is_mate(beta) && pos.non_pawn_material(pos.side_to_move())) return refinedValue - futility_margin(depth, 0); @@ -1126,8 +1092,8 @@ namespace { if ( !PvNode && !ss->skipNullMove && depth > OnePly - && refinedValue >= beta - (depth >= 4 * OnePly ? NullMoveMargin : 0) && !isCheck + && refinedValue >= beta - (depth >= 4 * OnePly ? NullMoveMargin : 0) && !value_is_mate(beta) && pos.non_pawn_material(pos.side_to_move())) { @@ -1176,7 +1142,7 @@ namespace { if (nullValue == value_mated_in(ply + 2)) mateThreat = true; - threatMove = (ss+1)->currentMove; + threatMove = (ss+1)->bestMove; if ( depth < ThreatDepth && (ss-1)->reduction && connected_moves(pos, (ss-1)->currentMove, threatMove)) @@ -1206,24 +1172,15 @@ namespace { // Initialize a MovePicker object for the current position MovePicker mp = MovePicker(pos, ttMove, depth, H, ss, (PvNode ? -VALUE_INFINITE : beta)); CheckInfo ci(pos); + ss->bestMove = MOVE_NONE; singleEvasion = isCheck && mp.number_of_evasions() == 1; singularExtensionNode = depth >= SingularExtensionDepth[PvNode] - && tte && tte->move() + && tte + && tte->move() && !excludedMove // Do not allow recursive singular extension search && is_lower_bound(tte->type()) && tte->depth() >= depth - 3 * OnePly; - // Avoid to do an expensive singular extension search on nodes where - // such search had already failed in the past. - if ( !PvNode - && singularExtensionNode - && depth < SingularExtensionDepth[PvNode] + 5 * OnePly) - { - TTEntry* ttx = TT.retrieve(pos.get_exclusion_key()); - if (ttx && is_lower_bound(ttx->type())) - singularExtensionNode = false; - } - // Step 10. Loop through moves // Loop through all legal moves until no moves remain or a beta cutoff occurs while ( bestValue < beta @@ -1249,9 +1206,22 @@ namespace { && move == tte->move() && ext < OnePly) { + // Avoid to do an expensive singular extension search on nodes where + // such search have already been done in the past, so assume the last + // singular extension search result is still valid. + if ( !PvNode + && depth < SingularExtensionDepth[PvNode] + 5 * OnePly + && (ttx = TT.retrieve(pos.get_exclusion_key())) != NULL) + { + if (is_upper_bound(ttx->type())) + ext = OnePly; + + singularExtensionNode = false; + } + Value ttValue = value_from_tt(tte->value(), ply); - if (abs(ttValue) < VALUE_KNOWN_WIN) + if (singularExtensionNode && abs(ttValue) < VALUE_KNOWN_WIN) { Value b = ttValue - SingularExtensionMargin; ss->excludedMove = move; @@ -1259,6 +1229,7 @@ namespace { Value v = search(pos, ss, b - 1, b, depth / 2, ply); ss->skipNullMove = false; ss->excludedMove = MOVE_NONE; + ss->bestMove = MOVE_NONE; if (v < b) ext = OnePly; } @@ -1368,7 +1339,7 @@ namespace { bestValue = value; if (value > alpha) { - if (PvNode && value < beta) // This guarantees that always: alpha < beta + if (PvNode && value < beta) // We want always alpha < beta alpha = value; if (value == value_mate_in(ply + 1)) @@ -1395,7 +1366,7 @@ namespace { // no legal moves, it must be mate or stalemate. // If one move was excluded return fail low score. if (!moveCount) - return excludedMove ? oldAlpha : (isCheck ? value_mated_in(ply) : VALUE_DRAW); + return excludedMove ? oldAlpha : isCheck ? value_mated_in(ply) : VALUE_DRAW; // Step 20. Update tables // If the search is not aborted, update the transposition table, @@ -1403,9 +1374,9 @@ namespace { if (AbortSearch || TM.thread_should_stop(threadID)) return bestValue; - ValueType f = (bestValue <= oldAlpha ? VALUE_TYPE_UPPER : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT); + ValueType vt = (bestValue <= oldAlpha ? VALUE_TYPE_UPPER : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT); move = (bestValue <= oldAlpha ? MOVE_NONE : ss->bestMove); - TT.store(posKey, value_to_tt(bestValue, ply), f, depth, move, ss->eval, ei.kingDanger[pos.side_to_move()]); + TT.store(posKey, value_to_tt(bestValue, ply), vt, depth, move, ss->eval, ei.kingDanger[pos.side_to_move()]); // Update killers and history only for non capture moves that fails high if (bestValue >= beta) @@ -1460,7 +1431,7 @@ namespace { if (!PvNode && tte && ok_to_use_TT(tte, depth, beta, ply)) { - ss->currentMove = ttMove; // Can be MOVE_NONE + ss->bestMove = ttMove; // Can be MOVE_NONE return value_from_tt(tte->value(), ply); } @@ -1478,6 +1449,7 @@ namespace { if (tte) { assert(tte->static_value() != VALUE_NONE); + ei.kingDanger[pos.side_to_move()] = tte->king_danger(); bestValue = tte->static_value(); } @@ -1587,8 +1559,8 @@ namespace { // Update transposition table Depth d = (depth == Depth(0) ? Depth(0) : Depth(-1)); - ValueType f = (bestValue <= oldAlpha ? VALUE_TYPE_UPPER : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT); - TT.store(pos.get_key(), value_to_tt(bestValue, ply), f, d, ss->bestMove, ss->eval, ei.kingDanger[pos.side_to_move()]); + ValueType vt = (bestValue <= oldAlpha ? VALUE_TYPE_UPPER : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT); + TT.store(pos.get_key(), value_to_tt(bestValue, ply), vt, d, ss->bestMove, ss->eval, ei.kingDanger[pos.side_to_move()]); // Update killers only for checking moves that fails high if ( bestValue >= beta @@ -2007,8 +1979,7 @@ namespace { Value refine_eval(const TTEntry* tte, Value defaultEval, int ply) { - if (!tte) - return defaultEval; + assert(tte); Value v = value_from_tt(tte->value(), ply); @@ -2064,8 +2035,7 @@ namespace { && before != VALUE_NONE && after != VALUE_NONE && pos.captured_piece() == NO_PIECE_TYPE - && !move_is_castle(m) - && !move_is_promotion(m)) + && !move_is_special(m)) H.set_gain(pos.piece_on(move_to(m)), move_to(m), -(before + after)); } @@ -2165,9 +2135,9 @@ namespace { bool stillAtFirstMove = FirstRootMove && !AspirationFailLow - && t > MaxSearchTime + ExtraSearchTime; + && t > TimeMgr.available_time(); - bool noMoreTime = t > AbsoluteMaxSearchTime + bool noMoreTime = t > TimeMgr.maximumSearchTime || stillAtFirstMove; if ( (Iteration >= 3 && UseTimeManagement && noMoreTime) @@ -2188,9 +2158,9 @@ namespace { bool stillAtFirstMove = FirstRootMove && !AspirationFailLow - && t > MaxSearchTime + ExtraSearchTime; + && t > TimeMgr.available_time(); - bool noMoreTime = t > AbsoluteMaxSearchTime + bool noMoreTime = t > TimeMgr.maximumSearchTime || stillAtFirstMove; if (Iteration >= 3 && UseTimeManagement && (noMoreTime || StopOnPonderhit))