X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=d073b7da31a2e14056bee54e2c4d45dbfd8b0ba7;hp=3b5cae4541eecec487b02bb3cb72c7233492e453;hb=b50921fd5c3e1753adecfea77557ad1afece7641;hpb=8ee0842c81ba41482d3373d4174bfed53b1bc9fc diff --git a/src/search.cpp b/src/search.cpp index 3b5cae45..d073b7da 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -199,7 +199,7 @@ namespace { Depth ThreatDepth; // heavy SMP read access // Last seconds noise filtering (LSN) - const bool UseLSNFiltering = false; + const bool UseLSNFiltering = true; const int LSNTime = 4000; // In milliseconds const Value LSNValue = value_from_centipawns(200); bool loseOnTime = false; @@ -288,7 +288,6 @@ namespace { bool ok_to_do_nullmove(const Position& pos); 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, Move movesSearched[], int moveCount); void update_killers(Move m, SearchStack& ss); @@ -308,7 +307,9 @@ namespace { bool thread_is_available(int slave, int master); bool idle_thread_exists(int master); bool split(const Position& pos, SearchStack* ss, int ply, - Value *alpha, Value *beta, Value *bestValue, Depth depth, int *moves, + Value *alpha, Value *beta, Value *bestValue, + const Value futilityValue, const Value approximateValue, + Depth depth, int *moves, MovePicker *mp, Bitboard dcCandidates, int master, bool pvNode); void wake_sleeping_threads(); @@ -866,9 +867,9 @@ namespace { << " currmovenumber " << i + 1 << std::endl; // Decide search depth for this move - bool moveIsCapture = pos.move_is_capture(move); + bool captureOrPromotion = pos.move_is_capture_or_promotion(move); bool dangerous; - ext = extension(pos, move, true, moveIsCapture, pos.move_is_check(move), false, false, &dangerous); + ext = extension(pos, move, true, captureOrPromotion, pos.move_is_check(move), false, false, &dangerous); newDepth = (Iteration - 2) * OnePly + ext + InitialDepth; // Make the move, and search it @@ -895,8 +896,7 @@ namespace { if ( newDepth >= 3*OnePly && i >= MultiPV + LMRPVMoves && !dangerous - && !moveIsCapture - && !move_is_promotion(move) + && !captureOrPromotion && !move_is_castle(move)) { ss[0].reduction = OnePly; @@ -1048,7 +1048,7 @@ namespace { EvalInfo ei; if (ply >= PLY_MAX - 1) - return evaluate(pos, ei, threadID); + return pos.is_check() ? quick_evaluate(pos) : evaluate(pos, ei, threadID); // Mate distance pruning Value oldAlpha = alpha; @@ -1091,13 +1091,13 @@ namespace { bool singleReply = (isCheck && mp.number_of_evasions() == 1); bool moveIsCheck = pos.move_is_check(move, dcCandidates); - bool moveIsCapture = pos.move_is_capture(move); + bool captureOrPromotion = pos.move_is_capture_or_promotion(move); movesSearched[moveCount++] = ss[ply].currentMove = move; // Decide the new search depth bool dangerous; - Depth ext = extension(pos, move, true, moveIsCapture, moveIsCheck, singleReply, mateThreat, &dangerous); + Depth ext = extension(pos, move, true, captureOrPromotion, moveIsCheck, singleReply, mateThreat, &dangerous); Depth newDepth = depth - OnePly + ext; // Make and search the move @@ -1113,8 +1113,7 @@ namespace { if ( depth >= 3*OnePly && moveCount >= LMRPVMoves && !dangerous - && !moveIsCapture - && !move_is_promotion(move) + && !captureOrPromotion && !move_is_castle(move) && !move_is_killer(move, ss[ply])) { @@ -1176,7 +1175,7 @@ namespace { && idle_thread_exists(threadID) && !AbortSearch && !thread_should_stop(threadID) - && split(pos, ss, ply, &alpha, &beta, &bestValue, depth, + && split(pos, ss, ply, &alpha, &beta, &bestValue, VALUE_NONE, VALUE_NONE, depth, &moveCount, &mp, dcCandidates, threadID, true)) break; } @@ -1198,7 +1197,7 @@ namespace { { BetaCounter.add(pos.side_to_move(), depth, threadID); Move m = ss[ply].pv[ply]; - if (ok_to_history(pos, m)) // Only non capture moves are considered + if (!pos.move_is_capture_or_promotion(m)) { update_history(pos, m, depth, movesSearched, moveCount); update_killers(m, ss[ply]); @@ -1238,7 +1237,7 @@ namespace { EvalInfo ei; if (ply >= PLY_MAX - 1) - return evaluate(pos, ei, threadID); + return pos.is_check() ? quick_evaluate(pos) : evaluate(pos, ei, threadID); // Mate distance pruning if (value_mated_in(ply) >= beta) @@ -1352,24 +1351,24 @@ namespace { bool singleReply = (isCheck && mp.number_of_evasions() == 1); bool moveIsCheck = pos.move_is_check(move, dcCandidates); - bool moveIsCapture = pos.move_is_capture(move); + bool captureOrPromotion = pos.move_is_capture_or_promotion(move); movesSearched[moveCount++] = ss[ply].currentMove = move; // Decide the new search depth bool dangerous; - Depth ext = extension(pos, move, false, moveIsCapture, moveIsCheck, singleReply, mateThreat, &dangerous); + Depth ext = extension(pos, move, false, captureOrPromotion, moveIsCheck, singleReply, mateThreat, &dangerous); Depth newDepth = depth - OnePly + ext; // Futility pruning if ( useFutilityPruning && !dangerous - && !moveIsCapture - && !move_is_promotion(move)) + && !captureOrPromotion) { // History pruning. See ok_to_prune() definition if ( moveCount >= 2 + int(depth) - && ok_to_prune(pos, move, ss[ply].threatMove, depth)) + && ok_to_prune(pos, move, ss[ply].threatMove, depth) + && bestValue > value_mated_in(PLY_MAX)) continue; // Value based pruning @@ -1397,8 +1396,7 @@ namespace { if ( depth >= 3*OnePly && moveCount >= LMRNonPVMoves && !dangerous - && !moveIsCapture - && !move_is_promotion(move) + && !captureOrPromotion && !move_is_castle(move) && !move_is_killer(move, ss[ply])) { @@ -1436,7 +1434,7 @@ namespace { && idle_thread_exists(threadID) && !AbortSearch && !thread_should_stop(threadID) - && split(pos, ss, ply, &beta, &beta, &bestValue, depth, &moveCount, + && split(pos, ss, ply, &beta, &beta, &bestValue, futilityValue, approximateEval, depth, &moveCount, &mp, dcCandidates, threadID, false)) break; } @@ -1457,7 +1455,7 @@ namespace { { BetaCounter.add(pos.side_to_move(), depth, threadID); Move m = ss[ply].pv[ply]; - if (ok_to_history(pos, m)) // Only non capture moves are considered + if (!pos.move_is_capture_or_promotion(m)) { update_history(pos, m, depth, movesSearched, moveCount); update_killers(m, ss[ply]); @@ -1529,8 +1527,8 @@ namespace { else staticValue = evaluate(pos, ei, threadID); - if (ply == PLY_MAX - 1) - return evaluate(pos, ei, threadID); + if (ply >= PLY_MAX - 1) + return pos.is_check() ? quick_evaluate(pos) : evaluate(pos, ei, threadID); // Initialize "stand pat score", and return it immediately if it is // at least beta. @@ -1593,6 +1591,7 @@ namespace { // Don't search captures and checks with negative SEE values if ( !isCheck + && move != ttMove && !move_is_promotion(move) && pos.see_sign(move) < 0) continue; @@ -1619,7 +1618,7 @@ namespace { // All legal moves have been searched. A special case: If we're in check // and no legal moves were found, it is checkmate. - if (pos.is_check() && moveCount == 0) // Mate! + if (!moveCount && pos.is_check()) // Mate! return value_mated_in(ply); assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE); @@ -1640,7 +1639,7 @@ namespace { } // Update killers only for good check moves - if (alpha >= beta && ok_to_history(pos, m)) // Only non capture moves are considered + if (alpha >= beta && !pos.move_is_capture_or_promotion(m)) update_killers(m, ss[ply]); return bestValue; @@ -1675,7 +1674,7 @@ namespace { assert(move_is_ok(move)); bool moveIsCheck = pos.move_is_check(move, sp->dcCandidates); - bool moveIsCapture = pos.move_is_capture(move); + bool captureOrPromotion = pos.move_is_capture_or_promotion(move); lock_grab(&(sp->lock)); int moveCount = ++sp->moves; @@ -1685,17 +1684,43 @@ namespace { // Decide the new search depth. bool dangerous; - Depth ext = extension(pos, move, false, moveIsCapture, moveIsCheck, false, false, &dangerous); + Depth ext = extension(pos, move, false, captureOrPromotion, moveIsCheck, false, false, &dangerous); Depth newDepth = sp->depth - OnePly + ext; // Prune? if ( useFutilityPruning && !dangerous - && !moveIsCapture - && !move_is_promotion(move) - && moveCount >= 2 + int(sp->depth) - && ok_to_prune(pos, move, ss[sp->ply].threatMove, sp->depth)) - continue; + && !captureOrPromotion) + { + // History pruning. See ok_to_prune() definition + if ( moveCount >= 2 + int(sp->depth) + && ok_to_prune(pos, move, ss[sp->ply].threatMove, sp->depth) + && sp->bestValue > value_mated_in(PLY_MAX)) + continue; + + // Value based pruning + if (sp->approximateEval < sp->beta) + { + if (sp->futilityValue == VALUE_NONE) + { + EvalInfo ei; + sp->futilityValue = evaluate(pos, ei, threadID) + + FutilityMargins[int(sp->depth) - 2]; + } + + if (sp->futilityValue < sp->beta) + { + if (sp->futilityValue > sp->bestValue) // Less then 1% of cases + { + lock_grab(&(sp->lock)); + if (sp->futilityValue > sp->bestValue) + sp->bestValue = sp->futilityValue; + lock_release(&(sp->lock)); + } + continue; + } + } + } // Make and search the move. StateInfo st; @@ -1705,8 +1730,7 @@ namespace { // if the move fails high will be re-searched at full depth. if ( !dangerous && moveCount >= LMRNonPVMoves - && !moveIsCapture - && !move_is_promotion(move) + && !captureOrPromotion && !move_is_castle(move) && !move_is_killer(move, ss[sp->ply])) { @@ -1729,21 +1753,24 @@ namespace { break; // New best move? - lock_grab(&(sp->lock)); - if (value > sp->bestValue && !thread_should_stop(threadID)) + if (value > sp->bestValue) // Less then 2% of cases { - sp->bestValue = value; - if (sp->bestValue >= sp->beta) + lock_grab(&(sp->lock)); + if (value > sp->bestValue && !thread_should_stop(threadID)) { - sp_update_pv(sp->parentSstack, ss, sp->ply); - for (int i = 0; i < ActiveThreads; i++) - if (i != threadID && (i == sp->master || sp->slaves[i])) - Threads[i].stop = true; + sp->bestValue = value; + if (sp->bestValue >= sp->beta) + { + sp_update_pv(sp->parentSstack, ss, sp->ply); + for (int i = 0; i < ActiveThreads; i++) + if (i != threadID && (i == sp->master || sp->slaves[i])) + Threads[i].stop = true; - sp->finished = true; - } + sp->finished = true; + } + } + lock_release(&(sp->lock)); } - lock_release(&(sp->lock)); } lock_grab(&(sp->lock)); @@ -1785,7 +1812,7 @@ namespace { && (move = sp->mp->get_next_move(sp->lock)) != MOVE_NONE) { bool moveIsCheck = pos.move_is_check(move, sp->dcCandidates); - bool moveIsCapture = pos.move_is_capture(move); + bool captureOrPromotion = pos.move_is_capture_or_promotion(move); assert(move_is_ok(move)); @@ -1797,7 +1824,7 @@ namespace { // Decide the new search depth. bool dangerous; - Depth ext = extension(pos, move, true, moveIsCapture, moveIsCheck, false, false, &dangerous); + Depth ext = extension(pos, move, true, captureOrPromotion, moveIsCheck, false, false, &dangerous); Depth newDepth = sp->depth - OnePly + ext; // Make and search the move. @@ -1808,8 +1835,7 @@ namespace { // if the move fails high will be re-searched at full depth. if ( !dangerous && moveCount >= LMRPVMoves - && !moveIsCapture - && !move_is_promotion(move) + && !captureOrPromotion && !move_is_castle(move) && !move_is_killer(move, ss[sp->ply])) { @@ -2234,8 +2260,8 @@ namespace { // extended, as example because the corresponding UCI option is set to zero, // the move is marked as 'dangerous' so, at least, we avoid to prune it. - Depth extension(const Position& pos, Move m, bool pvNode, bool capture, bool check, - bool singleReply, bool mateThreat, bool* dangerous) { + Depth extension(const Position& pos, Move m, bool pvNode, bool captureOrPromotion, + bool check, bool singleReply, bool mateThreat, bool* dangerous) { assert(m != MOVE_NONE); @@ -2269,7 +2295,7 @@ namespace { } } - if ( capture + if ( captureOrPromotion && pos.type_of_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(0)) @@ -2281,7 +2307,7 @@ namespace { } if ( pvNode - && capture + && captureOrPromotion && pos.type_of_piece_on(move_to(m)) != PAWN && pos.see_sign(m) >= 0) { @@ -2315,9 +2341,8 @@ namespace { assert(move_is_ok(m)); assert(threat == MOVE_NONE || move_is_ok(threat)); - assert(!move_is_promotion(m)); assert(!pos.move_is_check(m)); - assert(!pos.move_is_capture(m)); + assert(!pos.move_is_capture_or_promotion(m)); assert(!pos.move_is_passed_pawn_push(m)); assert(d >= OnePly); @@ -2379,15 +2404,6 @@ namespace { } - // ok_to_history() returns true if a move m can be stored - // in history. Should be a non capturing move nor a promotion. - - bool ok_to_history(const Position& pos, Move m) { - - return !pos.move_is_capture(m) && !move_is_promotion(m); - } - - // update_history() registers a good move that produced a beta-cutoff // in history and marks as failures all the other moves of that ply. @@ -2399,7 +2415,7 @@ namespace { for (int i = 0; i < moveCount - 1; i++) { assert(m != movesSearched[i]); - if (ok_to_history(pos, movesSearched[i])) + if (!pos.move_is_capture_or_promotion(movesSearched[i])) H.failure(pos.piece_on(move_from(movesSearched[i])), move_to(movesSearched[i])); } } @@ -2755,7 +2771,8 @@ namespace { // splitPoint->cpus becomes 0), split() returns true. bool split(const Position& p, SearchStack* sstck, int ply, - Value* alpha, Value* beta, Value* bestValue, Depth depth, int* moves, + Value* alpha, Value* beta, Value* bestValue, const Value futilityValue, + const Value approximateEval, Depth depth, int* moves, MovePicker* mp, Bitboard dcCandidates, int master, bool pvNode) { assert(p.is_ok()); @@ -2795,6 +2812,8 @@ namespace { splitPoint->pvNode = pvNode; splitPoint->dcCandidates = dcCandidates; splitPoint->bestValue = *bestValue; + splitPoint->futilityValue = futilityValue; + splitPoint->approximateEval = approximateEval; splitPoint->master = master; splitPoint->mp = mp; splitPoint->moves = *moves;