X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.cpp;h=b1fa91d0033d28b36e4fe7fe87f931de58adde0c;hp=539c486852ee278e0295deb7a53919a7fd634ac6;hb=2ca2c3f35b2e408fd97bdf7092f41e1e508eb7af;hpb=7b0a2f2a90b63d9e5e092786fbfb54cd8ad3d8e5 diff --git a/src/movepick.cpp b/src/movepick.cpp index 539c4868..b1fa91d0 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) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2015 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 @@ -49,10 +49,6 @@ namespace { } } - // Unary predicate used by std::partition to split positive scores from remaining - // ones so as to sort the two sets separately, with the second sort delayed. - inline bool has_positive_score(const ExtMove& ms) { return ms.score > 0; } - // Picks the best move in the range (begin, end) and moves it to the front. // It's faster than sorting all the moves in advance when there are few // moves e.g. possible captures. @@ -61,7 +57,7 @@ namespace { std::swap(*begin, *std::max_element(begin, end)); return begin; } -} +} // namespace /// Constructors of the MovePicker class. As arguments we pass information @@ -81,7 +77,7 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& followupmoves = fm; ss = s; - if (p.checkers()) + if (pos.checkers()) stage = EVASION; else @@ -92,30 +88,23 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& } MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& h, - Square sq) : pos(p), history(h), cur(moves), end(moves) { + Square s) : pos(p), history(h), cur(moves), end(moves) { assert(d <= DEPTH_ZERO); - if (p.checkers()) + if (pos.checkers()) stage = EVASION; else if (d > DEPTH_QS_NO_CHECKS) stage = QSEARCH_0; else if (d > DEPTH_QS_RECAPTURES) - { 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.capture_or_promotion(ttm)) - ttm = MOVE_NONE; - } else { stage = RECAPTURE; - recaptureSquare = sq; + recaptureSquare = s; ttm = MOVE_NONE; } @@ -142,8 +131,8 @@ MovePicker::MovePicker(const Position& p, Move ttm, const HistoryStats& h, Piece } -/// score() assign a numerical move ordering score to each move in a move list. -/// The moves with highest scores will be picked first. +/// score() assign a numerical value to each move in a move list. The moves with +/// highest values will be picked first. template<> void MovePicker::score() { // Winning and equal captures in the main search are ordered by MVV/LVA. @@ -164,14 +153,14 @@ void MovePicker::score() { for (ExtMove* it = moves; it != end; ++it) { m = it->move; - it->score = PieceValue[MG][pos.piece_on(to_sq(m))] - - type_of(pos.moved_piece(m)); + it->value = PieceValue[MG][pos.piece_on(to_sq(m))] + - Value(type_of(pos.moved_piece(m))); - if (type_of(m) == PROMOTION) - it->score += PieceValue[MG][promotion_type(m)] - PieceValue[MG][PAWN]; + if (type_of(m) == ENPASSANT) + it->value += PieceValue[MG][PAWN]; - else if (type_of(m) == ENPASSANT) - it->score += PieceValue[MG][PAWN]; + else if (type_of(m) == PROMOTION) + it->value += PieceValue[MG][promotion_type(m)] - PieceValue[MG][PAWN]; } } @@ -183,7 +172,7 @@ void MovePicker::score() { for (ExtMove* it = moves; it != end; ++it) { m = it->move; - it->score = history[pos.moved_piece(m)][to_sq(m)]; + it->value = history[pos.moved_piece(m)][to_sq(m)]; } } @@ -191,21 +180,21 @@ template<> void MovePicker::score() { // Try good captures ordered by MVV/LVA, then non-captures if destination square // is not under attack, ordered by history value, then bad-captures and quiet - // moves with a negative SEE. This last group is ordered by the SEE score. + // moves with a negative SEE. This last group is ordered by the SEE value. Move m; - Value seeScore; + Value see; for (ExtMove* it = moves; it != end; ++it) { m = it->move; - if ((seeScore = pos.see_sign(m)) < VALUE_ZERO) - it->score = seeScore - HistoryStats::Max; // At the bottom + if ((see = pos.see_sign(m)) < VALUE_ZERO) + it->value = see - HistoryStats::Max; // At the bottom else if (pos.capture(m)) - it->score = PieceValue[MG][pos.piece_on(to_sq(m))] - - type_of(pos.moved_piece(m)) + HistoryStats::Max; + it->value = PieceValue[MG][pos.piece_on(to_sq(m))] + - Value(type_of(pos.moved_piece(m))) + HistoryStats::Max; else - it->score = history[pos.moved_piece(m)][to_sq(m)]; + it->value = history[pos.moved_piece(m)][to_sq(m)]; } } @@ -254,7 +243,7 @@ void MovePicker::generate_next_stage() { case QUIETS_1_S1: endQuiets = end = generate(pos, moves); score(); - end = std::partition(cur, end, has_positive_score); + end = std::partition(cur, end, [](const ExtMove& m) { return m.value > VALUE_ZERO; }); insertion_sort(cur, end); return; @@ -283,6 +272,8 @@ void MovePicker::generate_next_stage() { case EVASION: case QSEARCH_0: case QSEARCH_1: case PROBCUT: case RECAPTURE: stage = STOP; + /* Fall through */ + case STOP: end = cur + 1; // Avoid another next_phase() call return; @@ -295,7 +286,7 @@ void MovePicker::generate_next_stage() { /// next_move() is the most important method of the MovePicker class. It returns /// a new pseudo legal move every time it is called, until there are no more moves -/// left. It picks the move with the biggest score from a list of generated moves +/// left. It picks the move with the biggest value from a list of generated moves /// taking care not to return the ttMove if it has already been searched. template<> Move MovePicker::next_move() { @@ -328,8 +319,8 @@ Move MovePicker::next_move() { case KILLERS_S1: move = (cur++)->move; if ( move != MOVE_NONE - && pos.pseudo_legal(move) && move != ttMove + && pos.pseudo_legal(move) && !pos.capture(move)) return move; break;