X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=8ba5b41af8be9cf182a02650dc9457d7fa515239;hp=ab34673463c57286d7ec4047a46755d6fc24701e;hb=d3608c4e79a29110f4c4a369d7207c6dd8e01f34;hpb=7bad50773a65c45b0b3f88eca7eddc6aa0f7f174 diff --git a/src/search.cpp b/src/search.cpp index ab346734..8ba5b41a 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -86,8 +86,9 @@ namespace { TimeManager TimeMgr; int BestMoveChanges; Value DrawValue[COLOR_NB]; - History Hist; - Gains Gain; + HistoryStats History; + GainsStats Gains; + CountermovesStats Countermoves; template Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth); @@ -145,7 +146,7 @@ void Search::init() { // Init futility move count array for (d = 0; d < 32; d++) - FutilityMoveCounts[d] = int(3.001 + 0.25 * pow(double(d), 2.0)); + FutilityMoveCounts[d] = int(3.001 + 0.3 * pow(double(d), 1.8)); } @@ -162,11 +163,11 @@ size_t Search::perft(Position& pos, Depth depth) { size_t cnt = 0; CheckInfo ci(pos); - for (MoveList ml(pos); !ml.end(); ++ml) + for (MoveList it(pos); *it; ++it) { - pos.do_move(ml.move(), st, ci, pos.move_gives_check(ml.move(), ci)); + pos.do_move(*it, st, ci, pos.move_gives_check(*it, ci)); cnt += perft(pos, depth - ONE_PLY); - pos.undo_move(ml.move()); + pos.undo_move(*it); } return cnt; @@ -264,6 +265,10 @@ void Search::think() { finalize: + // When search is stopped this info is not printed + sync_cout << "info nodes " << RootPos.nodes_searched() + << " time " << Time::now() - SearchTime + 1 << sync_endl; + // When we reach max depth we arrive here even without Signals.stop is raised, // but if we are pondering or in infinite search, according to UCI protocol, // we shouldn't print the best move before the GUI sends a "stop" or "ponderhit" @@ -299,8 +304,9 @@ namespace { bestValue = delta = -VALUE_INFINITE; ss->currentMove = MOVE_NULL; // Hack to skip update gains TT.new_search(); - Hist.clear(); - Gain.clear(); + History.clear(); + Gains.clear(); + Countermoves.clear(); PVSize = Options["MultiPV"]; Skill skill(Options["Skill Level"]); @@ -523,6 +529,7 @@ namespace { bestValue = -VALUE_INFINITE; ss->currentMove = threatMove = (ss+1)->excludedMove = bestMove = MOVE_NONE; ss->ply = (ss-1)->ply + 1; + ss->futilityMoveCount = 0; (ss+1)->skipNullMove = false; (ss+1)->reduction = DEPTH_ZERO; (ss+2)->killers[0] = (ss+2)->killers[1] = MOVE_NONE; @@ -533,7 +540,7 @@ namespace { if (!RootNode) { // Step 2. Check for aborted search and immediate draw - if (Signals.stop || pos.is_draw() || ss->ply > MAX_PLY) + if (Signals.stop || pos.is_draw() || ss->ply > MAX_PLY) return DrawValue[pos.side_to_move()]; // Step 3. Mate distance pruning. Even if we mate at the next move our score @@ -616,7 +623,7 @@ namespace { && type_of(move) == NORMAL) { Square to = to_sq(move); - Gain.update(pos.piece_on(to), to, -(ss-1)->staticEval - ss->staticEval); + Gains.update(pos.piece_on(to), to, -(ss-1)->staticEval - ss->staticEval); } // Step 6. Razoring (is omitted in PV nodes) @@ -643,10 +650,11 @@ namespace { && !ss->skipNullMove && depth < 4 * ONE_PLY && !inCheck - && eval - FutilityMargins[depth][0] >= beta + && eval - futility_margin(depth, (ss-1)->futilityMoveCount) >= beta && abs(beta) < VALUE_MATE_IN_MAX_PLY + && abs(eval) < VALUE_KNOWN_WIN && pos.non_pawn_material(pos.side_to_move())) - return eval - FutilityMargins[depth][0]; + return eval - futility_margin(depth, (ss-1)->futilityMoveCount); // Step 8. Null move search with verification search (is omitted in PV nodes) if ( !PvNode @@ -679,7 +687,7 @@ namespace { if (nullValue >= VALUE_MATE_IN_MAX_PLY) nullValue = beta; - if (depth < 6 * ONE_PLY) + if (depth < 12 * ONE_PLY) return nullValue; // Do verification search at high depths @@ -726,7 +734,7 @@ namespace { assert((ss-1)->currentMove != MOVE_NONE); assert((ss-1)->currentMove != MOVE_NULL); - MovePicker mp(pos, ttMove, Hist, pos.captured_piece_type()); + MovePicker mp(pos, ttMove, History, pos.captured_piece_type()); CheckInfo ci(pos); while ((move = mp.next_move()) != MOVE_NONE) @@ -758,7 +766,11 @@ namespace { split_point_start: // At split points actual search starts from here - MovePicker mp(pos, ttMove, depth, Hist, ss, PvNode ? -VALUE_INFINITE : beta); + Square prevMoveSq = to_sq((ss-1)->currentMove); + Move countermoves[] = { Countermoves[pos.piece_on(prevMoveSq)][prevMoveSq].first, + Countermoves[pos.piece_on(prevMoveSq)][prevMoveSq].second }; + + MovePicker mp(pos, ttMove, depth, History, countermoves, ss, PvNode ? -VALUE_INFINITE : beta); CheckInfo ci(pos); value = bestValue; // Workaround a bogus 'uninitialized' warning under gcc singularExtensionNode = !RootNode @@ -857,7 +869,7 @@ split_point_start: // At split points actual search starts from here && !captureOrPromotion && !inCheck && !dangerous - && move != ttMove + /* && move != ttMove Already implicit in the next condition */ && bestValue > VALUE_MATED_IN_MAX_PLY) { // Move count based pruning @@ -876,7 +888,7 @@ split_point_start: // At split points actual search starts from here // but fixing this made program slightly weaker. Depth predictedDepth = newDepth - reduction(depth, moveCount); futilityValue = ss->staticEval + ss->evalMargin + futility_margin(predictedDepth, moveCount) - + Gain[pos.piece_moved(move)][to_sq(move)]; + + Gains[pos.piece_moved(move)][to_sq(move)]; if (futilityValue < beta) { @@ -900,7 +912,13 @@ split_point_start: // At split points actual search starts from here continue; } + + // We have not pruned the move that will be searched, but remember how + // far in the move list we are to be more aggressive in the child node. + ss->futilityMoveCount = moveCount; } + else + ss->futilityMoveCount = 0; // Check for legality only before to do the move if (!RootNode && !SpNode && !pos.pl_move_is_legal(move, ci.pinned)) @@ -928,6 +946,9 @@ split_point_start: // At split points actual search starts from here && move != ss->killers[1]) { ss->reduction = reduction(depth, moveCount); + if (move == countermoves[0] || move == countermoves[1]) + ss->reduction = std::max(DEPTH_ZERO, ss->reduction-ONE_PLY); + Depth d = std::max(newDepth - ss->reduction, ONE_PLY); if (SpNode) alpha = splitPoint->alpha; @@ -1077,13 +1098,15 @@ split_point_start: // At split points actual search starts from here // Increase history value of the cut-off move Value bonus = Value(int(depth) * int(depth)); - Hist.update(pos.piece_moved(bestMove), to_sq(bestMove), bonus); + History.update(pos.piece_moved(bestMove), to_sq(bestMove), bonus); + if (is_ok((ss-1)->currentMove)) + Countermoves.update(pos.piece_on(prevMoveSq), prevMoveSq, bestMove); // Decrease history of all the other played non-capture moves for (int i = 0; i < playedMoveCount - 1; i++) { Move m = movesSearched[i]; - Hist.update(pos.piece_moved(m), to_sq(m), -bonus); + History.update(pos.piece_moved(m), to_sq(m), -bonus); } } } @@ -1129,7 +1152,7 @@ split_point_start: // At split points actual search starts from here ss->ply = (ss-1)->ply + 1; // Check for an instant draw or maximum ply reached - if (pos.is_draw() || ss->ply > MAX_PLY) + if (pos.is_draw() || ss->ply > MAX_PLY) return DrawValue[pos.side_to_move()]; // Decide whether or not to include checks, this fixes also the type of @@ -1196,7 +1219,7 @@ split_point_start: // At split points actual search starts from here // to search the moves. Because the depth is <= 0 here, only captures, // queen promotions and checks (only if depth >= DEPTH_QS_CHECKS) will // be generated. - MovePicker mp(pos, ttMove, depth, Hist, to_sq((ss-1)->currentMove)); + MovePicker mp(pos, ttMove, depth, History, to_sq((ss-1)->currentMove)); CheckInfo ci(pos); // Loop through the moves until no moves remain or a beta cutoff occurs @@ -1225,10 +1248,11 @@ split_point_start: // At split points actual search starts from here continue; } - // Prune moves with negative or equal SEE + // Prune moves with negative or equal SEE and also moves with positive + // SEE where capturing piece loses a tempo and SEE < beta - futilityBase. if ( futilityBase < beta && depth < DEPTH_ZERO - && pos.see_asymm(move, beta - futilityBase) <= 0) + && pos.see(move, beta - futilityBase) <= 0) { bestValue = std::max(bestValue, futilityBase); continue; @@ -1578,7 +1602,7 @@ void RootMove::extract_pv_from_tt(Position& pos) { && pos.is_pseudo_legal(m = tte->move()) // Local copy, TT could change && pos.pl_move_is_legal(m, pos.pinned_pieces()) && ply < MAX_PLY - && (!pos.is_draw() || ply < 2)); + && (!pos.is_draw() || ply < 2)); pv.push_back(MOVE_NONE); // Must be zero-terminating