X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=e7933f762422af11fe541156e10206ec3562b2bc;hp=41992efbc55b5625649ecfe380e81775af703356;hb=4ad6a3496b4ab2234e1a2436116be827be2d3a20;hpb=0cfb30e5be9e66766b3b8e5870b5737b48b1b632 diff --git a/src/search.cpp b/src/search.cpp index 41992efb..e7933f76 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -79,16 +79,9 @@ namespace { Move pv[PLY_MAX_PLUS_2]; }; - // RootMoveList struct is just a vector of RootMove objects, - // with an handful of methods above the standard ones. + // RootMoveList struct is mainly a std::vector of RootMove objects struct RootMoveList : public std::vector { - - typedef std::vector Base; - void init(Position& pos, Move searchMoves[]); - void sort() { insertion_sort(begin(), end()); } - void sort_first(int n) { insertion_sort(begin(), begin() + n); } - int bestMoveChanges; }; @@ -733,7 +726,7 @@ namespace { if (PvNode && thread.maxPly < ss->ply) thread.maxPly = ss->ply; - // Step 1. Initialize node and poll. Polling can abort search + // Step 1. Initialize node. if (!SpNode) { ss->currentMove = ss->bestMove = threatMove = (ss+1)->excludedMove = MOVE_NONE; @@ -749,18 +742,6 @@ namespace { goto split_point_start; } - if (pos.thread() == 0 && ++NodesSincePoll > NodesBetweenPolls) - { - NodesSincePoll = 0; - poll(pos); - } - - // Step 2. Check for aborted search and immediate draw - if (( StopRequest - || pos.is_draw() - || ss->ply > PLY_MAX) && !RootNode) - return VALUE_DRAW; - // Step 3. Mate distance pruning if (!RootNode) { @@ -921,7 +902,12 @@ namespace { if (pos.pl_move_is_legal(move, ci.pinned)) { pos.do_move(move, st, ci, pos.move_gives_check(move, ci)); - value = -search(pos, ss+1, -rbeta, -rbeta+1, rdepth); + + if (pos.is_draw() || ss->ply + 1 > PLY_MAX) + value = VALUE_DRAW; + else + value = -search(pos, ss+1, -rbeta, -rbeta+1, rdepth); + pos.undo_move(move); if (value >= rbeta) return value; @@ -1111,6 +1097,22 @@ split_point_start: // At split points actual search starts from here // Step 14. Make the move pos.do_move(move, st, ci, givesCheck); + // Step XX. Poll. Check if search should be aborted. + if (pos.thread() == 0 && ++NodesSincePoll > NodesBetweenPolls) + { + NodesSincePoll = 0; + poll(pos); + } + + // Step XX. Check for aborted search and immediate draw + if ( StopRequest + || pos.is_draw() + || ss->ply + 1 > PLY_MAX) + { + value = VALUE_DRAW; + goto undo; + } + // Step extra. pv search (only in PV nodes) // The first move in list is the expected PV if (isPvMove) @@ -1157,6 +1159,7 @@ split_point_start: // At split points actual search starts from here } // Step 17. Undo move +undo: pos.undo_move(move); assert(value > -VALUE_INFINITE && value < VALUE_INFINITE); @@ -1219,7 +1222,7 @@ split_point_start: // At split points actual search starts from here // because all the values but the first are usually set to // -VALUE_INFINITE and we want to keep the same order for all // the moves but the new PV that goes to head. - Rml.sort_first(moveCount); + sort(Rml.begin(), Rml.begin() + moveCount); // Update alpha. In multi-pv we don't use aspiration window, so set // alpha equal to minimum score among the PV lines searched so far. @@ -1319,10 +1322,6 @@ split_point_start: // At split points actual search starts from here ss->bestMove = ss->currentMove = MOVE_NONE; ss->ply = (ss-1)->ply + 1; - // Check for an instant draw or maximum ply reached - if (pos.is_draw() || ss->ply > PLY_MAX) - return VALUE_DRAW; - // Decide whether or not to include checks, this fixes also the type of // TT entry depth that we are going to use. Note that in qsearch we use // only two types of depth in TT: DEPTH_QS_CHECKS or DEPTH_QS_NO_CHECKS. @@ -1457,7 +1456,12 @@ split_point_start: // At split points actual search starts from here // Make and search the move pos.do_move(move, st, ci, givesCheck); - value = -qsearch(pos, ss+1, -beta, -alpha, depth-ONE_PLY); + + if (pos.is_draw() || ss->ply+1 > PLY_MAX) + value = VALUE_DRAW; + else + value = -qsearch(pos, ss+1, -beta, -alpha, depth-ONE_PLY); + pos.undo_move(move); assert(value > -VALUE_INFINITE && value < VALUE_INFINITE); @@ -1555,7 +1559,8 @@ split_point_start: // At split points actual search starts from here bool connected_moves(const Position& pos, Move m1, Move m2) { Square f1, t1, f2, t2; - Piece p; + Piece p1, p2; + Square ksq; assert(m1 && move_is_ok(m1)); assert(m2 && move_is_ok(m2)); @@ -1573,26 +1578,24 @@ split_point_start: // At split points actual search starts from here return true; // Case 3: Moving through the vacated square - if ( piece_is_slider(pos.piece_on(f2)) + p2 = pos.piece_on(f2); + if ( piece_is_slider(p2) && bit_is_set(squares_between(f2, t2), f1)) return true; // Case 4: The destination square for m2 is defended by the moving piece in m1 - p = pos.piece_on(t1); - if (bit_is_set(pos.attacks_from(p, t1), t2)) + p1 = pos.piece_on(t1); + if (bit_is_set(pos.attacks_from(p1, t1), t2)) return true; // Case 5: Discovered check, checking piece is the piece moved in m1 - if ( piece_is_slider(p) - && bit_is_set(squares_between(t1, pos.king_square(pos.side_to_move())), f2) - && !bit_is_set(squares_between(t1, pos.king_square(pos.side_to_move())), t2)) + ksq = pos.king_square(pos.side_to_move()); + if ( piece_is_slider(p1) + && bit_is_set(squares_between(t1, ksq), f2)) { - // discovered_check_candidates() works also if the Position's side to - // move is the opposite of the checking piece. - Color them = opposite_color(pos.side_to_move()); - Bitboard dcCandidates = pos.discovered_check_candidates(them); - - if (bit_is_set(dcCandidates, f2)) + Bitboard occ = pos.occupied_squares(); + clear_bit(&occ, f2); + if (bit_is_set(pos.attacks_from(p1, t1, occ), ksq)) return true; } return false; @@ -2031,7 +2034,7 @@ split_point_start: // At split points actual search starts from here while ( (tte = TT.probe(pos.get_key())) != NULL && tte->move() != MOVE_NONE && pos.move_is_pl(tte->move()) - && pos.pl_move_is_legal(tte->move(), pos.pinned_pieces(pos.side_to_move())) + && pos.pl_move_is_legal(tte->move(), pos.pinned_pieces()) && ply < PLY_MAX && (!pos.is_draw() || ply < 2)) { @@ -2093,7 +2096,7 @@ split_point_start: // At split points actual search starts from here break; } - Rml.sort(); + sort(Rml.begin(), Rml.end()); } } // namespace