X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.cpp;h=c4eaa902e292e64cdea5858f4f9ae3318f07ec92;hp=5c8338c0c19ab96d08f55879015d8f422002985c;hb=917944e9c5324cc9659e630570e1852270b22bd4;hpb=30c2e3828a5ea143e6190680dcd8e9d93fd17840 diff --git a/src/movepick.cpp b/src/movepick.cpp index 5c8338c0..c4eaa902 100644 --- a/src/movepick.cpp +++ b/src/movepick.cpp @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -25,7 +25,7 @@ namespace { - enum Sequencer { + enum Stages { MAIN_SEARCH, CAPTURES_S1, KILLERS_S1, QUIETS_1_S1, QUIETS_2_S1, BAD_CAPTURES_S1, EVASION, EVASIONS_S2, QSEARCH_0, CAPTURES_S3, QUIET_CHECKS_S3, @@ -36,9 +36,9 @@ namespace { }; // Our insertion sort, guaranteed to be stable, as is needed - void insertion_sort(MoveStack* begin, MoveStack* end) + void insertion_sort(ExtMove* begin, ExtMove* end) { - MoveStack tmp, *p, *q; + ExtMove tmp, *p, *q; for (p = begin + 1; p < end; ++p) { @@ -51,12 +51,12 @@ namespace { // Unary predicate used by std::partition to split positive scores from remaining // ones so to sort separately the two sets, and with the second sort delayed. - inline bool has_positive_score(const MoveStack& ms) { return ms.score > 0; } + inline bool has_positive_score(const ExtMove& ms) { return ms.score > 0; } // Picks and moves to the front the best move in the range [begin, end), // it is faster than sorting all the moves in advance when moves are few, as // normally are the possible captures. - inline MoveStack* pick_best(MoveStack* begin, MoveStack* end) + inline ExtMove* pick_best(ExtMove* begin, ExtMove* end) { std::swap(*begin, *std::max_element(begin, end)); return begin; @@ -70,89 +70,85 @@ namespace { /// search captures, promotions and some checks) and about how important good /// move ordering is at the current node. -MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h, - Search::Stack* s, Value beta) : pos(p), Hist(h), depth(d) { +MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& h, + Move* cm, Search::Stack* s) : pos(p), history(h), depth(d) { assert(d > DEPTH_ZERO); - captureThreshold = 0; cur = end = moves; endBadCaptures = moves + MAX_MOVES - 1; + countermoves = cm; ss = s; if (p.checkers()) - phase = EVASION; + stage = EVASION; else - { - phase = MAIN_SEARCH; - - killers[0].move = ss->killers[0]; - killers[1].move = ss->killers[1]; - - // Consider sligtly negative captures as good if at low depth and far from beta - if (ss && ss->staticEval < beta - PawnValueMg && d < 3 * ONE_PLY) - captureThreshold = -PawnValueMg; + stage = MAIN_SEARCH; - // Consider negative captures as good if still enough to reach beta - else if (ss && ss->staticEval > beta) - captureThreshold = beta - ss->staticEval; - } - - ttMove = (ttm && pos.is_pseudo_legal(ttm) ? ttm : MOVE_NONE); + ttMove = (ttm && pos.pseudo_legal(ttm) ? ttm : MOVE_NONE); end += (ttMove != MOVE_NONE); } -MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h, - Square sq) : pos(p), Hist(h), cur(moves), end(moves) { +MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& h, + Square sq) : pos(p), history(h), cur(moves), end(moves) { assert(d <= DEPTH_ZERO); if (p.checkers()) - phase = EVASION; + stage = EVASION; else if (d > DEPTH_QS_NO_CHECKS) - phase = QSEARCH_0; + stage = QSEARCH_0; else if (d > DEPTH_QS_RECAPTURES) { - phase = QSEARCH_1; + stage = QSEARCH_1; // Skip TT move if is not a capture or a promotion, this avoids qsearch // tree explosion due to a possible perpetual check or similar rare cases // when TT table is full. - if (ttm && !pos.is_capture_or_promotion(ttm)) + if (ttm && !pos.capture_or_promotion(ttm)) ttm = MOVE_NONE; } else { - phase = RECAPTURE; + stage = RECAPTURE; recaptureSquare = sq; ttm = MOVE_NONE; } - ttMove = (ttm && pos.is_pseudo_legal(ttm) ? ttm : MOVE_NONE); + ttMove = (ttm && pos.pseudo_legal(ttm) ? ttm : MOVE_NONE); end += (ttMove != MOVE_NONE); } -MovePicker::MovePicker(const Position& p, Move ttm, const History& h, PieceType pt) - : pos(p), Hist(h), cur(moves), end(moves) { +MovePicker::MovePicker(const Position& p, Move ttm, const HistoryStats& h, PieceType pt) + : pos(p), history(h), cur(moves), end(moves) { assert(!pos.checkers()); - phase = PROBCUT; + stage = PROBCUT; // In ProbCut we generate only captures better than parent's captured piece captureThreshold = PieceValue[MG][pt]; - ttMove = (ttm && pos.is_pseudo_legal(ttm) ? ttm : MOVE_NONE); + ttMove = (ttm && pos.pseudo_legal(ttm) ? ttm : MOVE_NONE); - if (ttMove && (!pos.is_capture(ttMove) || pos.see(ttMove) <= captureThreshold)) + if (ttMove && (!pos.capture(ttMove) || pos.see(ttMove) <= captureThreshold)) ttMove = MOVE_NONE; end += (ttMove != MOVE_NONE); } +/// quiet_moves() returns a pointer to the beginning of moves array. It +/// is used to access already tried quiet moves when updating history. + +const ExtMove* MovePicker::quiet_moves() const { + return stage == KILLERS_S1 ? killers + : stage == QUIETS_1_S1 || stage == QUIETS_2_S1 ? moves : NULL; +} + + /// score() assign a numerical move ordering score to each move in a move list. /// The moves with highest scores will be picked first. template<> @@ -172,11 +168,11 @@ void MovePicker::score() { // some SEE calls in case we get a cutoff (idea from Pablo Vazquez). Move m; - for (MoveStack* it = moves; it != end; ++it) + for (ExtMove* it = moves; it != end; ++it) { m = it->move; it->score = PieceValue[MG][pos.piece_on(to_sq(m))] - - type_of(pos.piece_moved(m)); + - type_of(pos.moved_piece(m)); if (type_of(m) == PROMOTION) it->score += PieceValue[MG][promotion_type(m)] - PieceValue[MG][PAWN]; @@ -191,10 +187,10 @@ void MovePicker::score() { Move m; - for (MoveStack* it = moves; it != end; ++it) + for (ExtMove* it = moves; it != end; ++it) { m = it->move; - it->score = Hist[pos.piece_moved(m)][to_sq(m)]; + it->score = history[pos.moved_piece(m)][to_sq(m)]; } } @@ -206,17 +202,17 @@ void MovePicker::score() { Move m; int seeScore; - for (MoveStack* it = moves; it != end; ++it) + for (ExtMove* it = moves; it != end; ++it) { m = it->move; if ((seeScore = pos.see_sign(m)) < 0) - it->score = seeScore - History::Max; // At the bottom + it->score = seeScore - HistoryStats::Max; // At the bottom - else if (pos.is_capture(m)) + else if (pos.capture(m)) it->score = PieceValue[MG][pos.piece_on(to_sq(m))] - - type_of(pos.piece_moved(m)) + History::Max; + - type_of(pos.moved_piece(m)) + HistoryStats::Max; else - it->score = Hist[pos.piece_moved(m)][to_sq(m)]; + it->score = history[pos.moved_piece(m)][to_sq(m)]; } } @@ -228,7 +224,7 @@ void MovePicker::generate_next() { cur = moves; - switch (++phase) { + switch (++stage) { case CAPTURES_S1: case CAPTURES_S3: case CAPTURES_S4: case CAPTURES_S5: case CAPTURES_S6: end = generate(pos, moves); @@ -238,6 +234,19 @@ void MovePicker::generate_next() { case KILLERS_S1: cur = killers; end = cur + 2; + + killers[0].move = ss->killers[0]; + killers[1].move = ss->killers[1]; + killers[2].move = killers[3].move = MOVE_NONE; + + // Be sure countermoves are different from killers + for (int i = 0; i < 2; ++i) + if (countermoves[i] != cur->move && countermoves[i] != (cur+1)->move) + (end++)->move = countermoves[i]; + + if (countermoves[1] && countermoves[1] == countermoves[0]) // Due to SMP races + killers[3].move = MOVE_NONE; + return; case QUIETS_1_S1: @@ -271,7 +280,7 @@ void MovePicker::generate_next() { return; case EVASION: case QSEARCH_0: case QSEARCH_1: case PROBCUT: case RECAPTURE: - phase = STOP; + stage = STOP; case STOP: end = cur + 1; // Avoid another next_phase() call return; @@ -296,19 +305,17 @@ Move MovePicker::next_move() { while (cur == end) generate_next(); - switch (phase) { + switch (stage) { case MAIN_SEARCH: case EVASION: case QSEARCH_0: case QSEARCH_1: case PROBCUT: - cur++; + ++cur; return ttMove; case CAPTURES_S1: move = pick_best(cur++, end)->move; if (move != ttMove) { - assert(captureThreshold <= 0); // Otherwise we cannot use see_sign() - - if (pos.see_sign(move) >= captureThreshold) + if (pos.see_sign(move) >= 0) return move; // Losing capture, move it to the tail of the array @@ -319,9 +326,9 @@ Move MovePicker::next_move() { case KILLERS_S1: move = (cur++)->move; if ( move != MOVE_NONE - && pos.is_pseudo_legal(move) + && pos.pseudo_legal(move) && move != ttMove - && !pos.is_capture(move)) + && !pos.capture(move)) return move; break; @@ -329,7 +336,9 @@ Move MovePicker::next_move() { move = (cur++)->move; if ( move != ttMove && move != killers[0].move - && move != killers[1].move) + && move != killers[1].move + && move != killers[2].move + && move != killers[3].move) return move; break; @@ -374,4 +383,4 @@ Move MovePicker::next_move() { /// from the split point's shared MovePicker object. This function is not thread /// safe so must be lock protected by the caller. template<> -Move MovePicker::next_move() { return ss->sp->movePicker->next_move(); } +Move MovePicker::next_move() { return ss->splitPoint->movePicker->next_move(); }