X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=1fe723aec461e20a303582484349b9696ca9c552;hp=cc0f42e9c9ac1b004938a29968b554001e75c9f6;hb=6738b65be97af10e4b5b783dc8ad21ae0faf36a8;hpb=243fa483d7b329ad8512c86eb152cca7a0982674 diff --git a/src/position.cpp b/src/position.cpp index cc0f42e9..abe7fde3 100644 --- a/src/position.cpp +++ b/src/position.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 Marco Costalba + Copyright (C) 2008-2010 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 @@ -17,56 +17,142 @@ along with this program. If not, see . */ - -//// -//// Includes -//// - #include #include #include +#include #include +#include -#include "mersenne.h" +#include "bitcount.h" #include "movegen.h" -#include "movepick.h" #include "position.h" #include "psqtab.h" -#include "san.h" +#include "rkiss.h" +#include "tt.h" #include "ucioption.h" - -//// -//// Variables -//// - -extern SearchStack EmptySearchStack; - -int Position::castleRightsMask[64]; +using std::string; +using std::cout; +using std::endl; Key Position::zobrist[2][8][64]; Key Position::zobEp[64]; Key Position::zobCastle[16]; -Key Position::zobMaterial[2][8][16]; Key Position::zobSideToMove; +Key Position::zobExclusion; + +Score Position::PieceSquareTable[16][64]; + +// Material values arrays, indexed by Piece +const Value Position::PieceValueMidgame[17] = { + VALUE_ZERO, + PawnValueMidgame, KnightValueMidgame, BishopValueMidgame, + RookValueMidgame, QueenValueMidgame, VALUE_ZERO, + VALUE_ZERO, VALUE_ZERO, + PawnValueMidgame, KnightValueMidgame, BishopValueMidgame, + RookValueMidgame, QueenValueMidgame +}; + +const Value Position::PieceValueEndgame[17] = { + VALUE_ZERO, + PawnValueEndgame, KnightValueEndgame, BishopValueEndgame, + RookValueEndgame, QueenValueEndgame, VALUE_ZERO, + VALUE_ZERO, VALUE_ZERO, + PawnValueEndgame, KnightValueEndgame, BishopValueEndgame, + RookValueEndgame, QueenValueEndgame +}; + +// Material values array used by SEE, indexed by PieceType +const Value Position::seeValues[] = { + VALUE_ZERO, + PawnValueMidgame, KnightValueMidgame, BishopValueMidgame, + RookValueMidgame, QueenValueMidgame, QueenValueMidgame*10 +}; + + +namespace { + + // Bonus for having the side to move (modified by Joona Kiiski) + const Score TempoValue = make_score(48, 22); + + struct PieceLetters : public std::map { + + PieceLetters() { + + operator[]('K') = WK; operator[]('k') = BK; + operator[]('Q') = WQ; operator[]('q') = BQ; + operator[]('R') = WR; operator[]('r') = BR; + operator[]('B') = WB; operator[]('b') = BB; + operator[]('N') = WN; operator[]('n') = BN; + operator[]('P') = WP; operator[]('p') = BP; + operator[](' ') = PIECE_NONE; + operator[]('.') = PIECE_NONE_DARK_SQ; + } -Value Position::MgPieceSquareTable[16][64]; -Value Position::EgPieceSquareTable[16][64]; + char from_piece(Piece p) const { -static bool RequestPending = false; + std::map::const_iterator it; + for (it = begin(); it != end(); ++it) + if (it->second == p) + return it->first; -//// -//// Functions -//// + assert(false); + return 0; + } + }; + + PieceLetters pieceLetters; +} -/// Constructors -Position::Position(const Position& pos) { - copy(pos); +/// CheckInfo c'tor + +CheckInfo::CheckInfo(const Position& pos) { + + Color us = pos.side_to_move(); + Color them = opposite_color(us); + + ksq = pos.king_square(them); + dcCandidates = pos.discovered_check_candidates(us); + + checkSq[PAWN] = pos.attacks_from(ksq, them); + checkSq[KNIGHT] = pos.attacks_from(ksq); + checkSq[BISHOP] = pos.attacks_from(ksq); + checkSq[ROOK] = pos.attacks_from(ksq); + checkSq[QUEEN] = checkSq[BISHOP] | checkSq[ROOK]; + checkSq[KING] = EmptyBoardBB; +} + + +/// Position c'tors. Here we always create a copy of the original position +/// or the FEN string, we want the new born Position object do not depend +/// on any external data so we detach state pointer from the source one. + +Position::Position(const Position& pos, int th) { + + memcpy(this, &pos, sizeof(Position)); + detach(); // Always detach() in copy c'tor to avoid surprises + threadID = th; + nodes = 0; +} + +Position::Position(const string& fen, bool isChess960, int th) { + + from_fen(fen, isChess960); + threadID = th; } -Position::Position(const std::string& fen) { - from_fen(fen); + +/// Position::detach() copies the content of the current state and castling +/// masks inside the position itself. This is needed when the st pointee could +/// become stale, as example because the caller is about to going out of scope. + +void Position::detach() { + + startState = *st; + st = &startState; + st->previous = NULL; // as a safe guard } @@ -74,334 +160,362 @@ Position::Position(const std::string& fen) { /// string. This function is not very robust - make sure that input FENs are /// correct (this is assumed to be the responsibility of the GUI). -void Position::from_fen(const std::string& fen) { +void Position::from_fen(const string& fen, bool isChess960) { +/* + A FEN string defines a particular position using only the ASCII character set. + + A FEN string contains six fields. The separator between fields is a space. The fields are: + + 1) Piece placement (from white's perspective). Each rank is described, starting with rank 8 and ending + with rank 1; within each rank, the contents of each square are described from file A through file H. + Following the Standard Algebraic Notation (SAN), each piece is identified by a single letter taken + from the standard English names. White pieces are designated using upper-case letters ("PNBRQK") + while Black take lowercase ("pnbrqk"). Blank squares are noted using digits 1 through 8 (the number + of blank squares), and "/" separate ranks. + + 2) Active color. "w" means white moves next, "b" means black. - static const std::string pieceLetters = "KQRBNPkqrbnp"; - static const Piece pieces[] = { WK, WQ, WR, WB, WN, WP, BK, BQ, BR, BB, BN, BP }; + 3) Castling availability. If neither side can castle, this is "-". Otherwise, this has one or more + letters: "K" (White can castle kingside), "Q" (White can castle queenside), "k" (Black can castle + kingside), and/or "q" (Black can castle queenside). + + 4) En passant target square in algebraic notation. If there's no en passant target square, this is "-". + If a pawn has just made a 2-square move, this is the position "behind" the pawn. This is recorded + regardless of whether there is a pawn in position to make an en passant capture. + + 5) Halfmove clock: This is the number of halfmoves since the last pawn advance or capture. This is used + to determine if a draw can be claimed under the fifty-move rule. + + 6) Fullmove number: The number of the full move. It starts at 1, and is incremented after Black's move. +*/ + + char token; + int hmc, fmn; + std::istringstream ss(fen); + Square sq = SQ_A8; clear(); - // Board - Rank rank = RANK_8; - File file = FILE_A; - size_t i = 0; - for ( ; fen[i] != ' '; i++) + // 1. Piece placement field + while (ss.get(token) && token != ' ') { - if (isdigit(fen[i])) + if (pieceLetters.find(token) != pieceLetters.end()) { - // Skip the given number of files - file += (fen[i] - '1' + 1); - continue; + put_piece(pieceLetters[token], sq); + sq++; } - else if (fen[i] == '/') - { - file = FILE_A; - rank--; - continue; - } - size_t idx = pieceLetters.find(fen[i]); - if (idx == std::string::npos) - { - std::cout << "Error in FEN at character " << i << std::endl; - return; - } - Square square = make_square(file, rank); - put_piece(pieces[idx], square); - file++; + else if (isdigit(token)) + sq += Square(token - '0'); // Skip the given number of files + else if (token == '/') + sq -= SQ_A3; // Jump back of 2 rows + else + goto incorrect_fen; } - // Side to move - i++; - if (fen[i] != 'w' && fen[i] != 'b') - { - std::cout << "Error in FEN at character " << i << std::endl; - return; - } - sideToMove = (fen[i] == 'w' ? WHITE : BLACK); + // 2. Active color + if (!ss.get(token) || (token != 'w' && token != 'b')) + goto incorrect_fen; - // Castling rights - i++; - if (fen[i] != ' ') + sideToMove = (token == 'w' ? WHITE : BLACK); + + if (!ss.get(token) || token != ' ') + goto incorrect_fen; + + // 3. Castling availability + while (ss.get(token) && token != ' ') + if (!set_castling_rights(token)) + goto incorrect_fen; + + // 4. En passant square + char col, row; + if ( (ss.get(col) && (col >= 'a' && col <= 'h')) + && (ss.get(row) && (row == '3' || row == '6'))) { - std::cout << "Error in FEN at character " << i << std::endl; - return; - } + st->epSquare = make_square(file_from_char(col), rank_from_char(row)); - i++; - while(strchr("KQkqabcdefghABCDEFGH-", fen[i])) { - if (fen[i] == '-') - { - i++; - break; - } - else if(fen[i] == 'K') allow_oo(WHITE); - else if(fen[i] == 'Q') allow_ooo(WHITE); - else if(fen[i] == 'k') allow_oo(BLACK); - else if(fen[i] == 'q') allow_ooo(BLACK); - else if(fen[i] >= 'A' && fen[i] <= 'H') { - File rookFile, kingFile = FILE_NONE; - for(Square square = SQ_B1; square <= SQ_G1; square++) - if(piece_on(square) == WK) - kingFile = square_file(square); - if(kingFile == FILE_NONE) { - std::cout << "Error in FEN at character " << i << std::endl; - return; - } - initialKFile = kingFile; - rookFile = File(fen[i] - 'A') + FILE_A; - if(rookFile < initialKFile) { - allow_ooo(WHITE); - initialQRFile = rookFile; - } - else { - allow_oo(WHITE); - initialKRFile = rookFile; - } - } - else if(fen[i] >= 'a' && fen[i] <= 'h') { - File rookFile, kingFile = FILE_NONE; - for(Square square = SQ_B8; square <= SQ_G8; square++) - if(piece_on(square) == BK) - kingFile = square_file(square); - if(kingFile == FILE_NONE) { - std::cout << "Error in FEN at character " << i << std::endl; - return; - } - initialKFile = kingFile; - rookFile = File(fen[i] - 'a') + FILE_A; - if(rookFile < initialKFile) { - allow_ooo(BLACK); - initialQRFile = rookFile; - } - else { - allow_oo(BLACK); - initialKRFile = rookFile; - } - } - else { - std::cout << "Error in FEN at character " << i << std::endl; - return; - } - i++; + // Ignore if no capture is possible + Color them = opposite_color(sideToMove); + if (!(attacks_from(st->epSquare, them) & pieces(PAWN, sideToMove))) + st->epSquare = SQ_NONE; } - // Skip blanks - while (fen[i] == ' ') - i++; - - // En passant square - if ( i < fen.length() - 2 - && (fen[i] >= 'a' && fen[i] <= 'h') - && (fen[i+1] == '3' || fen[i+1] == '6')) - st->epSquare = square_from_string(fen.substr(i, 2)); + // 5. Halfmove clock + if (ss >> hmc) + st->rule50 = hmc; - // Various initialisation - for (Square sq = SQ_A1; sq <= SQ_H8; sq++) - castleRightsMask[sq] = ALL_CASTLES; + // 6. Fullmove number + if (ss >> fmn) + startPosPlyCounter = (fmn - 1) * 2 + int(sideToMove == BLACK); - castleRightsMask[make_square(initialKFile, RANK_1)] ^= (WHITE_OO|WHITE_OOO); - castleRightsMask[make_square(initialKFile, RANK_8)] ^= (BLACK_OO|BLACK_OOO); + // Various initialisations + castleRightsMask[make_square(initialKFile, RANK_1)] ^= WHITE_OO | WHITE_OOO; + castleRightsMask[make_square(initialKFile, RANK_8)] ^= BLACK_OO | BLACK_OOO; castleRightsMask[make_square(initialKRFile, RANK_1)] ^= WHITE_OO; castleRightsMask[make_square(initialKRFile, RANK_8)] ^= BLACK_OO; castleRightsMask[make_square(initialQRFile, RANK_1)] ^= WHITE_OOO; castleRightsMask[make_square(initialQRFile, RANK_8)] ^= BLACK_OOO; + chess960 = isChess960; find_checkers(); - find_pinned(); st->key = compute_key(); st->pawnKey = compute_pawn_key(); st->materialKey = compute_material_key(); - st->mgValue = compute_value(); - st->egValue = compute_value(); - npMaterial[WHITE] = compute_non_pawn_material(WHITE); - npMaterial[BLACK] = compute_non_pawn_material(BLACK); + st->value = compute_value(); + st->npMaterial[WHITE] = compute_non_pawn_material(WHITE); + st->npMaterial[BLACK] = compute_non_pawn_material(BLACK); + return; + +incorrect_fen: + cout << "Error in FEN string: " << fen << endl; } -/// Position::to_fen() converts the position object to a FEN string. This is -/// probably only useful for debugging. +/// Position::set_castling_rights() sets castling parameters castling avaiability. +/// This function is compatible with 3 standards: Normal FEN standard, Shredder-FEN +/// that uses the letters of the columns on which the rooks began the game instead +/// of KQkq and also X-FEN standard that, in case of Chess960, if an inner Rook is +/// associated with the castling right, the traditional castling tag will be replaced +/// by the file letter of the involved rook as for the Shredder-FEN. -const std::string Position::to_fen() const { +bool Position::set_castling_rights(char token) { - static const std::string pieceLetters = " PNBRQK pnbrqk"; - std::string fen; - int skip; + Color c = token >= 'a' ? BLACK : WHITE; + Square sqA = (c == WHITE ? SQ_A1 : SQ_A8); + Square sqH = (c == WHITE ? SQ_H1 : SQ_H8); + Piece rook = (c == WHITE ? WR : BR); - for (Rank rank = RANK_8; rank >= RANK_1; rank--) + initialKFile = square_file(king_square(c)); + token = char(toupper(token)); + + if (token == 'K') + { + for (Square sq = sqH; sq >= sqA; sq--) + if (piece_on(sq) == rook) + { + do_allow_oo(c); + initialKRFile = square_file(sq); + break; + } + } + else if (token == 'Q') + { + for (Square sq = sqA; sq <= sqH; sq++) + if (piece_on(sq) == rook) + { + do_allow_ooo(c); + initialQRFile = square_file(sq); + break; + } + } + else if (token >= 'A' && token <= 'H') + { + File rookFile = File(token - 'A') + FILE_A; + if (rookFile < initialKFile) + { + do_allow_ooo(c); + initialQRFile = rookFile; + } + else + { + do_allow_oo(c); + initialKRFile = rookFile; + } + } + else + return token == '-'; + + return true; +} + + +/// Position::to_fen() returns a FEN representation of the position. In case +/// of Chess960 the Shredder-FEN notation is used. Mainly a debugging function. + +const string Position::to_fen() const { + + string fen; + Square sq; + char emptyCnt = '0'; + + for (Rank rank = RANK_8; rank >= RANK_1; rank--, fen += '/') { - skip = 0; for (File file = FILE_A; file <= FILE_H; file++) { - Square sq = make_square(file, rank); - if (!square_is_occupied(sq)) - { skip++; - continue; - } - if (skip > 0) + sq = make_square(file, rank); + + if (square_is_occupied(sq)) { - fen += (char)skip + '0'; - skip = 0; - } - fen += pieceLetters[piece_on(sq)]; + if (emptyCnt != '0') + { + fen += emptyCnt; + emptyCnt = '0'; + } + fen += pieceLetters.from_piece(piece_on(sq)); + } else + emptyCnt++; } - if (skip > 0) - fen += (char)skip + '0'; - fen += (rank > RANK_1 ? '/' : ' '); + if (emptyCnt != '0') + { + fen += emptyCnt; + emptyCnt = '0'; + } } - fen += (sideToMove == WHITE ? "w " : "b "); - if (st->castleRights != NO_CASTLES) + + fen += (sideToMove == WHITE ? " w " : " b "); + + if (st->castleRights != CASTLES_NONE) { - if (can_castle_kingside(WHITE)) fen += 'K'; - if (can_castle_queenside(WHITE)) fen += 'Q'; - if (can_castle_kingside(BLACK)) fen += 'k'; - if (can_castle_queenside(BLACK)) fen += 'q'; - } else - fen += '-'; + if (can_castle_kingside(WHITE)) + fen += chess960 ? char(toupper(file_to_char(initialKRFile))) : 'K'; - fen += ' '; - if (ep_square() != SQ_NONE) - fen += square_to_string(ep_square()); - else + if (can_castle_queenside(WHITE)) + fen += chess960 ? char(toupper(file_to_char(initialQRFile))) : 'Q'; + + if (can_castle_kingside(BLACK)) + fen += chess960 ? file_to_char(initialKRFile) : 'k'; + + if (can_castle_queenside(BLACK)) + fen += chess960 ? file_to_char(initialQRFile) : 'q'; + } else fen += '-'; + fen += (ep_square() == SQ_NONE ? " -" : " " + square_to_string(ep_square())); return fen; } /// Position::print() prints an ASCII representation of the position to -/// the standard output. If a move is given then also the san is print. - -void Position::print(Move m) const { +/// the standard output. If a move is given then also the san is printed. - static const std::string pieceLetters = " PNBRQK PNBRQK ."; +void Position::print(Move move) const { - // Check for reentrancy, as example when called from inside - // MovePicker that is used also here in move_to_san() - if (RequestPending) - return; + const char* dottedLine = "\n+---+---+---+---+---+---+---+---+\n"; - RequestPending = true; - - std::cout << std::endl; - if (m != MOVE_NONE) + if (move) { - std::string col = (color_of_piece_on(move_from(m)) == BLACK ? ".." : ""); - std::cout << "Move is: " << col << move_to_san(*this, m) << std::endl; + Position p(*this, thread()); + string dd = (color_of_piece_on(move_from(move)) == BLACK ? ".." : ""); + cout << "\nMove is: " << dd << move_to_san(p, move); } + for (Rank rank = RANK_8; rank >= RANK_1; rank--) { - std::cout << "+---+---+---+---+---+---+---+---+" << std::endl; + cout << dottedLine << '|'; for (File file = FILE_A; file <= FILE_H; file++) { Square sq = make_square(file, rank); Piece piece = piece_on(sq); - if (piece == EMPTY && square_color(sq) == WHITE) - piece = NO_PIECE; - char col = (color_of_piece_on(sq) == BLACK ? '=' : ' '); - std::cout << '|' << col << pieceLetters[piece] << col; + if (piece == PIECE_NONE && square_color(sq) == DARK) + piece = PIECE_NONE_DARK_SQ; + + char c = (color_of_piece_on(sq) == BLACK ? '=' : ' '); + cout << c << pieceLetters.from_piece(piece) << c << '|'; } - std::cout << '|' << std::endl; } - std::cout << "+---+---+---+---+---+---+---+---+" << std::endl - << "Fen is: " << to_fen() << std::endl - << "Key is: " << st->key << std::endl; - - RequestPending = false; + cout << dottedLine << "Fen is: " << to_fen() << "\nKey is: " << st->key << endl; } -/// Position::copy() creates a copy of the input position. - -void Position::copy(const Position &pos) { +/// Position:hidden_checkers<>() returns a bitboard of all pinned (against the +/// king) pieces for the given color and for the given pinner type. Or, when +/// template parameter FindPinned is false, the pieces of the given color +/// candidate for a discovery check against the enemy king. +/// Bitboard checkersBB must be already updated when looking for pinners. - memcpy(this, &pos, sizeof(Position)); -} +template +Bitboard Position::hidden_checkers(Color c) const { + Bitboard result = EmptyBoardBB; + Bitboard pinners = pieces_of_color(FindPinned ? opposite_color(c) : c); -/// Position:hidden_checks<>() returns a bitboard of all pinned (against the -/// king) pieces for the given color and for the given pinner type. Or, when -/// template parameter FindPinned is false, the pinned pieces of opposite color -/// that are, indeed, the pieces candidate for a discovery check. -/// Note that checkersBB bitboard must be already updated. -template -Bitboard Position::hidden_checks(Color c, Square ksq, Bitboard& pinners) const { + // Pinned pieces protect our king, dicovery checks attack + // the enemy king. + Square ksq = king_square(FindPinned ? c : opposite_color(c)); - Square s; - Bitboard sliders, result = EmptyBoardBB; + // Pinners are sliders, not checkers, that give check when candidate pinned is removed + pinners &= (pieces(ROOK, QUEEN) & RookPseudoAttacks[ksq]) | (pieces(BISHOP, QUEEN) & BishopPseudoAttacks[ksq]); - if (Piece == ROOK) // Resolved at compile time - sliders = rooks_and_queens(FindPinned ? opposite_color(c) : c) & RookPseudoAttacks[ksq]; - else - sliders = bishops_and_queens(FindPinned ? opposite_color(c) : c) & BishopPseudoAttacks[ksq]; + if (FindPinned && pinners) + pinners &= ~st->checkersBB; - if (sliders && (!FindPinned || (sliders & ~st->checkersBB))) + while (pinners) { - // King blockers are candidate pinned pieces - Bitboard candidate_pinned = piece_attacks(ksq) & pieces_of_color(c); + Square s = pop_1st_bit(&pinners); + Bitboard b = squares_between(s, ksq) & occupied_squares(); - // Pinners are sliders, not checkers, that give check when - // candidate pinned are removed. - pinners = (FindPinned ? sliders & ~st->checkersBB : sliders); + assert(b); - if (Piece == ROOK) - pinners &= rook_attacks_bb(ksq, occupied_squares() ^ candidate_pinned); - else - pinners &= bishop_attacks_bb(ksq, occupied_squares() ^ candidate_pinned); - - // Finally for each pinner find the corresponding pinned piece (if same color of king) - // or discovery checker (if opposite color) among the candidates. - Bitboard p = pinners; - while (p) - { - s = pop_1st_bit(&p); - result |= (squares_between(s, ksq) & candidate_pinned); - } + if ( !(b & (b - 1)) // Only one bit set? + && (b & pieces_of_color(c))) // Is an our piece? + result |= b; } - else - pinners = EmptyBoardBB; - return result; } -/// Position::attacks_to() computes a bitboard containing all pieces which -/// attacks a given square. There are two versions of this function: One -/// which finds attackers of both colors, and one which only finds the -/// attackers for one side. +/// Position:pinned_pieces() returns a bitboard of all pinned (against the +/// king) pieces for the given color. Note that checkersBB bitboard must +/// be already updated. + +Bitboard Position::pinned_pieces(Color c) const { + + return hidden_checkers(c); +} + + +/// Position:discovered_check_candidates() returns a bitboard containing all +/// pieces for the given side which are candidates for giving a discovered +/// check. Contrary to pinned_pieces() here there is no need of checkersBB +/// to be already updated. + +Bitboard Position::discovered_check_candidates(Color c) const { + + return hidden_checkers(c); +} + +/// Position::attackers_to() computes a bitboard containing all pieces which +/// attacks a given square. -Bitboard Position::attacks_to(Square s) const { +Bitboard Position::attackers_to(Square s) const { - return (pawn_attacks(BLACK, s) & pawns(WHITE)) - | (pawn_attacks(WHITE, s) & pawns(BLACK)) - | (piece_attacks(s) & pieces_of_type(KNIGHT)) - | (piece_attacks(s) & rooks_and_queens()) - | (piece_attacks(s) & bishops_and_queens()) - | (piece_attacks(s) & pieces_of_type(KING)); + return (attacks_from(s, BLACK) & pieces(PAWN, WHITE)) + | (attacks_from(s, WHITE) & pieces(PAWN, BLACK)) + | (attacks_from(s) & pieces(KNIGHT)) + | (attacks_from(s) & pieces(ROOK, QUEEN)) + | (attacks_from(s) & pieces(BISHOP, QUEEN)) + | (attacks_from(s) & pieces(KING)); } -/// Position::piece_attacks_square() tests whether the piece on square f -/// attacks square t. +/// Position::attacks_from() computes a bitboard of all attacks +/// of a given piece put in a given square. + +Bitboard Position::attacks_from(Piece p, Square s) const { -bool Position::piece_attacks_square(Piece p, Square f, Square t) const { + assert(square_is_ok(s)); + + switch (p) + { + case WB: case BB: return attacks_from(s); + case WR: case BR: return attacks_from(s); + case WQ: case BQ: return attacks_from(s); + default: return StepAttacksBB[p][s]; + } +} - assert(square_is_ok(f)); - assert(square_is_ok(t)); +Bitboard Position::attacks_from(Piece p, Square s, Bitboard occ) { + + assert(square_is_ok(s)); switch (p) { - case WP: return pawn_attacks_square(WHITE, f, t); - case BP: return pawn_attacks_square(BLACK, f, t); - case WN: case BN: return piece_attacks_square(f, t); - case WB: case BB: return piece_attacks_square(f, t); - case WR: case BR: return piece_attacks_square(f, t); - case WQ: case BQ: return piece_attacks_square(f, t); - case WK: case BK: return piece_attacks_square(f, t); - default: break; + case WB: case BB: return bishop_attacks_bb(s, occ); + case WR: case BR: return rook_attacks_bb(s, occ); + case WQ: case BQ: return bishop_attacks_bb(s, occ) | rook_attacks_bb(s, occ); + default: return StepAttacksBB[p][s]; } - return false; } @@ -413,288 +527,244 @@ bool Position::move_attacks_square(Move m, Square s) const { assert(move_is_ok(m)); assert(square_is_ok(s)); + Bitboard occ, xray; Square f = move_from(m), t = move_to(m); assert(square_is_occupied(f)); - if (piece_attacks_square(piece_on(f), t, s)) + if (bit_is_set(attacks_from(piece_on(f), t), s)) return true; // Move the piece and scan for X-ray attacks behind it - Bitboard occ = occupied_squares(); - Color us = color_of_piece_on(f); - clear_bit(&occ, f); - set_bit(&occ, t); - Bitboard xray = ( (rook_attacks_bb(s, occ) & rooks_and_queens()) - |(bishop_attacks_bb(s, occ) & bishops_and_queens())) & pieces_of_color(us); + occ = occupied_squares(); + do_move_bb(&occ, make_move_bb(f, t)); + xray = ( (rook_attacks_bb(s, occ) & pieces(ROOK, QUEEN)) + |(bishop_attacks_bb(s, occ) & pieces(BISHOP, QUEEN))) + & pieces_of_color(color_of_piece_on(f)); // If we have attacks we need to verify that are caused by our move // and are not already existent ones. - return xray && (xray ^ (xray & piece_attacks(s))); + return xray && (xray ^ (xray & attacks_from(s))); } /// Position::find_checkers() computes the checkersBB bitboard, which /// contains a nonzero bit for each checking piece (0, 1 or 2). It -/// currently works by calling Position::attacks_to, which is probably +/// currently works by calling Position::attackers_to, which is probably /// inefficient. Consider rewriting this function to use the last move /// played, like in non-bitboard versions of Glaurung. void Position::find_checkers() { Color us = side_to_move(); - st->checkersBB = attacks_to(king_square(us), opposite_color(us)); -} - - -/// Position:find_pinned() computes the pinned, pinners and dcCandidates -/// bitboards for both colors. Bitboard checkersBB must be already updated. - -void Position::find_pinned() { - - Bitboard p1, p2; - Square ksq; - - for (Color c = WHITE; c <= BLACK; c++) - { - ksq = king_square(c); - st->pinned[c] = hidden_checks(c, ksq, p1) | hidden_checks(c, ksq, p2); - st->pinners[c] = p1 | p2; - ksq = king_square(opposite_color(c)); - st->dcCandidates[c] = hidden_checks(c, ksq, p1) | hidden_checks(c, ksq, p2); - } + st->checkersBB = attackers_to(king_square(us)) & pieces_of_color(opposite_color(us)); } /// Position::pl_move_is_legal() tests whether a pseudo-legal move is legal -bool Position::pl_move_is_legal(Move m) const { +bool Position::pl_move_is_legal(Move m, Bitboard pinned) const { assert(is_ok()); assert(move_is_ok(m)); - - // If we're in check, all pseudo-legal moves are legal, because our - // check evasion generator only generates true legal moves. - if (is_check()) - return true; + assert(pinned == pinned_pieces(side_to_move())); // Castling moves are checked for legality during move generation. if (move_is_castle(m)) return true; - Color us = side_to_move(); - Color them = opposite_color(us); - Square from = move_from(m); - Square ksq = king_square(us); - - assert(color_of_piece_on(from) == us); - assert(piece_on(ksq) == piece_of_color_and_type(us, KING)); - - // En passant captures are a tricky special case. Because they are + // En passant captures are a tricky special case. Because they are // rather uncommon, we do it simply by testing whether the king is attacked // after the move is made if (move_is_ep(m)) { + Color us = side_to_move(); + Color them = opposite_color(us); + Square from = move_from(m); Square to = move_to(m); Square capsq = make_square(square_file(to), square_rank(from)); + Square ksq = king_square(us); Bitboard b = occupied_squares(); assert(to == ep_square()); - assert(piece_on(from) == piece_of_color_and_type(us, PAWN)); - assert(piece_on(capsq) == piece_of_color_and_type(them, PAWN)); - assert(piece_on(to) == EMPTY); + assert(piece_on(from) == make_piece(us, PAWN)); + assert(piece_on(capsq) == make_piece(them, PAWN)); + assert(piece_on(to) == PIECE_NONE); clear_bit(&b, from); clear_bit(&b, capsq); set_bit(&b, to); - return !(rook_attacks_bb(ksq, b) & rooks_and_queens(them)) - && !(bishop_attacks_bb(ksq, b) & bishops_and_queens(them)); + return !(rook_attacks_bb(ksq, b) & pieces(ROOK, QUEEN, them)) + && !(bishop_attacks_bb(ksq, b) & pieces(BISHOP, QUEEN, them)); } + Color us = side_to_move(); + Square from = move_from(m); + + assert(color_of_piece_on(from) == us); + assert(piece_on(king_square(us)) == make_piece(us, KING)); + // If the moving piece is a king, check whether the destination // square is attacked by the opponent. - if (from == ksq) - return !(square_is_attacked(move_to(m), them)); + if (type_of_piece_on(from) == KING) + return !(attackers_to(move_to(m)) & pieces_of_color(opposite_color(us))); // A non-king move is legal if and only if it is not pinned or it // is moving along the ray towards or away from the king. - return ( !bit_is_set(pinned_pieces(us), from) - || (direction_between_squares(from, ksq) == direction_between_squares(move_to(m), ksq))); + return !pinned + || !bit_is_set(pinned, from) + || squares_aligned(from, move_to(m), king_square(us)); } -/// Position::move_is_check() tests whether a pseudo-legal move is a check +/// Position::pl_move_is_evasion() tests whether a pseudo-legal move is a legal evasion -bool Position::move_is_check(Move m) const { - - assert(is_ok()); - assert(move_is_ok(m)); +bool Position::pl_move_is_evasion(Move m, Bitboard pinned) const +{ + assert(is_check()); Color us = side_to_move(); - Color them = opposite_color(us); Square from = move_from(m); Square to = move_to(m); - Square ksq = king_square(them); - Bitboard dcCandidates = discovered_check_candidates(us); - assert(color_of_piece_on(from) == us); - assert(piece_on(ksq) == piece_of_color_and_type(them, KING)); - - // Proceed according to the type of the moving piece - switch (type_of_piece_on(from)) - { - case PAWN: + // King moves and en-passant captures are verified in pl_move_is_legal() + if (type_of_piece_on(from) == KING || move_is_ep(m)) + return pl_move_is_legal(m, pinned); - if (bit_is_set(pawn_attacks(them, ksq), to)) // Normal check? - return true; + Bitboard target = checkers(); + Square checksq = pop_1st_bit(&target); - if ( bit_is_set(dcCandidates, from) // Discovered check? - && (direction_between_squares(from, ksq) != direction_between_squares(to, ksq))) - return true; + if (target) // double check ? + return false; - if (move_promotion(m)) // Promotion with check? - { - Bitboard b = occupied_squares(); - clear_bit(&b, from); + // Our move must be a blocking evasion or a capture of the checking piece + target = squares_between(checksq, king_square(us)) | checkers(); + return bit_is_set(target, to) && pl_move_is_legal(m, pinned); +} - switch (move_promotion(m)) - { - case KNIGHT: - return bit_is_set(piece_attacks(to), ksq); - case BISHOP: - return bit_is_set(bishop_attacks_bb(to, b), ksq); - case ROOK: - return bit_is_set(rook_attacks_bb(to, b), ksq); - case QUEEN: - return bit_is_set(queen_attacks_bb(to, b), ksq); - default: - assert(false); - } - } - // En passant capture with check? We have already handled the case - // of direct checks and ordinary discovered check, the only case we - // need to handle is the unusual case of a discovered check through the - // captured pawn. - else if (move_is_ep(m)) - { - Square capsq = make_square(square_file(to), square_rank(from)); - Bitboard b = occupied_squares(); - clear_bit(&b, from); - clear_bit(&b, capsq); - set_bit(&b, to); - return (rook_attacks_bb(ksq, b) & rooks_and_queens(us)) - ||(bishop_attacks_bb(ksq, b) & bishops_and_queens(us)); - } - return false; - case KNIGHT: - return bit_is_set(dcCandidates, from) // Discovered check? - || bit_is_set(piece_attacks(ksq), to); // Normal check? +/// Position::move_is_check() tests whether a pseudo-legal move is a check - case BISHOP: - return bit_is_set(dcCandidates, from) // Discovered check? - || bit_is_set(piece_attacks(ksq), to); // Normal check? +bool Position::move_is_check(Move m) const { - case ROOK: - return bit_is_set(dcCandidates, from) // Discovered check? - || bit_is_set(piece_attacks(ksq), to); // Normal check? + return move_is_check(m, CheckInfo(*this)); +} - case QUEEN: - // Discovered checks are impossible! - assert(!bit_is_set(dcCandidates, from)); - return bit_is_set(piece_attacks(ksq), to); // Normal check? +bool Position::move_is_check(Move m, const CheckInfo& ci) const { - case KING: - // Discovered check? - if ( bit_is_set(dcCandidates, from) - && (direction_between_squares(from, ksq) != direction_between_squares(to, ksq))) - return true; + assert(is_ok()); + assert(move_is_ok(m)); + assert(ci.dcCandidates == discovered_check_candidates(side_to_move())); + assert(color_of_piece_on(move_from(m)) == side_to_move()); + assert(piece_on(ci.ksq) == make_piece(opposite_color(side_to_move()), KING)); - // Castling with check? - if (move_is_castle(m)) - { - Square kfrom, kto, rfrom, rto; - Bitboard b = occupied_squares(); - kfrom = from; - rfrom = to; + Square from = move_from(m); + Square to = move_to(m); + PieceType pt = type_of_piece_on(from); - if (rfrom > kfrom) - { - kto = relative_square(us, SQ_G1); - rto = relative_square(us, SQ_F1); - } else { - kto = relative_square(us, SQ_C1); - rto = relative_square(us, SQ_D1); - } - clear_bit(&b, kfrom); - clear_bit(&b, rfrom); - set_bit(&b, rto); - set_bit(&b, kto); - return bit_is_set(rook_attacks_bb(rto, b), ksq); - } - return false; + // Direct check ? + if (bit_is_set(ci.checkSq[pt], to)) + return true; - default: // NO_PIECE_TYPE - break; + // Discovery check ? + if (ci.dcCandidates && bit_is_set(ci.dcCandidates, from)) + { + // For pawn and king moves we need to verify also direction + if ( (pt != PAWN && pt != KING) + || !squares_aligned(from, to, ci.ksq)) + return true; } - assert(false); - return false; -} + // Can we skip the ugly special cases ? + if (!move_is_special(m)) + return false; -/// Position::move_is_capture() tests whether a move from the current -/// position is a capture. Move must not be MOVE_NONE. + Color us = side_to_move(); + Bitboard b = occupied_squares(); -bool Position::move_is_capture(Move m) const { + // Promotion with check ? + if (move_is_promotion(m)) + { + clear_bit(&b, from); - assert(m != MOVE_NONE); + switch (move_promotion_piece(m)) + { + case KNIGHT: + return bit_is_set(attacks_from(to), ci.ksq); + case BISHOP: + return bit_is_set(bishop_attacks_bb(to, b), ci.ksq); + case ROOK: + return bit_is_set(rook_attacks_bb(to, b), ci.ksq); + case QUEEN: + return bit_is_set(queen_attacks_bb(to, b), ci.ksq); + default: + assert(false); + } + } - return ( !square_is_empty(move_to(m)) - && (color_of_piece_on(move_to(m)) != color_of_piece_on(move_from(m))) - ) - || move_is_ep(m); -} + // En passant capture with check ? We have already handled the case + // of direct checks and ordinary discovered check, the only case we + // need to handle is the unusual case of a discovered check through + // the captured pawn. + if (move_is_ep(m)) + { + Square capsq = make_square(square_file(to), square_rank(from)); + clear_bit(&b, from); + clear_bit(&b, capsq); + set_bit(&b, to); + return (rook_attacks_bb(ci.ksq, b) & pieces(ROOK, QUEEN, us)) + ||(bishop_attacks_bb(ci.ksq, b) & pieces(BISHOP, QUEEN, us)); + } + // Castling with check ? + if (move_is_castle(m)) + { + Square kfrom, kto, rfrom, rto; + kfrom = from; + rfrom = to; -/// Position::update_checkers() is a private method to udpate chekers info + if (rfrom > kfrom) + { + kto = relative_square(us, SQ_G1); + rto = relative_square(us, SQ_F1); + } else { + kto = relative_square(us, SQ_C1); + rto = relative_square(us, SQ_D1); + } + clear_bit(&b, kfrom); + clear_bit(&b, rfrom); + set_bit(&b, rto); + set_bit(&b, kto); + return bit_is_set(rook_attacks_bb(rto, b), ci.ksq); + } -template -inline void Position::update_checkers(Bitboard* pCheckersBB, Square ksq, Square from, - Square to, Bitboard dcCandidates) { + return false; +} - if (Piece != KING && bit_is_set(piece_attacks(ksq), to)) - set_bit(pCheckersBB, to); - if (Piece != QUEEN && bit_is_set(dcCandidates, from)) - { - if (Piece != ROOK) - (*pCheckersBB) |= (piece_attacks(ksq) & rooks_and_queens(side_to_move())); +/// Position::do_setup_move() makes a permanent move on the board. +/// It should be used when setting up a position on board. +/// You can't undo the move. - if (Piece != BISHOP) - (*pCheckersBB) |= (piece_attacks(ksq) & bishops_and_queens(side_to_move())); - } -} +void Position::do_setup_move(Move m) { + StateInfo newSt; -/// Position::init_new_state() copies from the current state the fields -/// that will be updated incrementally, skips the fields, like bitboards -/// that will be recalculated form scratch anyway. + do_move(m, newSt); -void Position::init_new_state(StateInfo& newSt) { + // Reset "game ply" in case we made a non-reversible move. + // "game ply" is used for repetition detection. + if (st->rule50 == 0) + st->gamePly = 0; - newSt.key = st->key; - newSt.pawnKey = st->pawnKey; - newSt.materialKey = st->materialKey; - newSt.castleRights = st->castleRights; - newSt.rule50 = st->rule50; - newSt.epSquare = st->epSquare; - newSt.mgValue = st->mgValue; - newSt.egValue = st->egValue; - newSt.capture = NO_PIECE_TYPE; - newSt.previous = st; -} + // Update the number of plies played from the starting position + startPosPlyCounter++; + // Our StateInfo newSt is about going out of scope so copy + // its content inside pos before it disappears. + detach(); +} /// Position::do_move() makes a move, and saves all information necessary /// to a StateInfo object. The move is assumed to be legal. @@ -702,134 +772,211 @@ void Position::init_new_state(StateInfo& newSt) { void Position::do_move(Move m, StateInfo& newSt) { + CheckInfo ci(*this); + do_move(m, newSt, ci, move_is_check(m, ci)); +} + +void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveIsCheck) { + assert(is_ok()); assert(move_is_ok(m)); + assert(&newSt != st); + + nodes++; + Key key = st->key; + + // Copy some fields of old state to our new StateInfo object except the + // ones which are recalculated from scratch anyway, then switch our state + // pointer to point to the new, ready to be updated, state. + struct ReducedStateInfo { + Key pawnKey, materialKey; + int castleRights, rule50, gamePly, pliesFromNull; + Square epSquare; + Score value; + Value npMaterial[2]; + }; - // Get now the current (before to move) dc candidates that we will use - // in update_checkers(). - Bitboard oldDcCandidates = discovered_check_candidates(side_to_move()); + memcpy(&newSt, st, sizeof(ReducedStateInfo)); - // Copy some fields of old state to our new StateInfo object (except the - // captured piece, which is taken care of later) and switch state pointer - // to point to the new, ready to be updated, state. - init_new_state(newSt); + newSt.previous = st; st = &newSt; // Save the current key to the history[] array, in order to be able to // detect repetition draws. - history[gamePly] = st->key; + history[st->gamePly++] = key; + + // Update side to move + key ^= zobSideToMove; // Increment the 50 moves rule draw counter. Resetting it to zero in the // case of non-reversible moves is taken care of later. st->rule50++; + st->pliesFromNull++; if (move_is_castle(m)) + { + st->key = key; do_castle_move(m); - else if (move_promotion(m)) - do_promotion_move(m); - else if (move_is_ep(m)) - do_ep_move(m); - else + return; + } + + Color us = side_to_move(); + Color them = opposite_color(us); + Square from = move_from(m); + Square to = move_to(m); + bool ep = move_is_ep(m); + bool pm = move_is_promotion(m); + + Piece piece = piece_on(from); + PieceType pt = type_of_piece(piece); + PieceType capture = ep ? PAWN : type_of_piece_on(to); + + assert(color_of_piece_on(from) == us); + assert(color_of_piece_on(to) == them || square_is_empty(to)); + assert(!(ep || pm) || piece == make_piece(us, PAWN)); + assert(!pm || relative_rank(us, to) == RANK_8); + + if (capture) + do_capture_move(key, capture, them, to, ep); + + // Update hash key + key ^= zobrist[us][pt][from] ^ zobrist[us][pt][to]; + + // Reset en passant square + if (st->epSquare != SQ_NONE) { - Color us = side_to_move(); - Color them = opposite_color(us); - Square from = move_from(m); - Square to = move_to(m); + key ^= zobEp[st->epSquare]; + st->epSquare = SQ_NONE; + } - assert(color_of_piece_on(from) == us); - assert(color_of_piece_on(to) == them || piece_on(to) == EMPTY); + // Update castle rights, try to shortcut a common case + int cm = castleRightsMask[from] & castleRightsMask[to]; + if (cm != ALL_CASTLES && ((cm & st->castleRights) != st->castleRights)) + { + key ^= zobCastle[st->castleRights]; + st->castleRights &= castleRightsMask[from]; + st->castleRights &= castleRightsMask[to]; + key ^= zobCastle[st->castleRights]; + } - PieceType piece = type_of_piece_on(from); + // Prefetch TT access as soon as we know key is updated + prefetch((char*)TT.first_entry(key)); - st->capture = type_of_piece_on(to); + // Move the piece + Bitboard move_bb = make_move_bb(from, to); + do_move_bb(&(byColorBB[us]), move_bb); + do_move_bb(&(byTypeBB[pt]), move_bb); + do_move_bb(&(byTypeBB[0]), move_bb); // HACK: byTypeBB[0] == occupied squares - if (st->capture) - do_capture_move(m, st->capture, them, to); + board[to] = board[from]; + board[from] = PIECE_NONE; - // Move the piece - clear_bit(&(byColorBB[us]), from); - clear_bit(&(byTypeBB[piece]), from); - clear_bit(&(byTypeBB[0]), from); // HACK: byTypeBB[0] == occupied squares - set_bit(&(byColorBB[us]), to); - set_bit(&(byTypeBB[piece]), to); - set_bit(&(byTypeBB[0]), to); // HACK: byTypeBB[0] == occupied squares - board[to] = board[from]; - board[from] = EMPTY; + // Update piece lists, note that index[from] is not updated and + // becomes stale. This works as long as index[] is accessed just + // by known occupied squares. + index[to] = index[from]; + pieceList[us][pt][index[to]] = to; - // Update hash key - st->key ^= zobrist[us][piece][from] ^ zobrist[us][piece][to]; + // If the moving piece was a pawn do some special extra work + if (pt == PAWN) + { + // Reset rule 50 draw counter + st->rule50 = 0; - // Update incremental scores - st->mgValue -= pst(us, piece, from); - st->mgValue += pst(us, piece, to); - st->egValue -= pst(us, piece, from); - st->egValue += pst(us, piece, to); + // Update pawn hash key and prefetch in L1/L2 cache + st->pawnKey ^= zobrist[us][PAWN][from] ^ zobrist[us][PAWN][to]; - // If the moving piece was a king, update the king square - if (piece == KING) - kingSquare[us] = to; + // Set en passant square, only if moved pawn can be captured + if ((to ^ from) == 16) + { + if (attacks_from(from + (us == WHITE ? DELTA_N : DELTA_S), us) & pieces(PAWN, them)) + { + st->epSquare = Square((int(from) + int(to)) / 2); + key ^= zobEp[st->epSquare]; + } + } - // Reset en passant square - if (st->epSquare != SQ_NONE) - { - st->key ^= zobEp[st->epSquare]; - st->epSquare = SQ_NONE; - } + if (pm) // promotion ? + { + PieceType promotion = move_promotion_piece(m); - // If the moving piece was a pawn do some special extra work - if (piece == PAWN) - { - // Reset rule 50 draw counter - st->rule50 = 0; + assert(promotion >= KNIGHT && promotion <= QUEEN); - // Update pawn hash key - st->pawnKey ^= zobrist[us][PAWN][from] ^ zobrist[us][PAWN][to]; + // Insert promoted piece instead of pawn + clear_bit(&(byTypeBB[PAWN]), to); + set_bit(&(byTypeBB[promotion]), to); + board[to] = make_piece(us, promotion); - // Set en passant square, only if moved pawn can be captured - if (abs(int(to) - int(from)) == 16) - { - if ( (us == WHITE && (pawn_attacks(WHITE, from + DELTA_N) & pawns(BLACK))) - || (us == BLACK && (pawn_attacks(BLACK, from + DELTA_S) & pawns(WHITE)))) - { - st->epSquare = Square((int(from) + int(to)) / 2); - st->key ^= zobEp[st->epSquare]; - } - } - } + // Update piece counts + pieceCount[us][promotion]++; + pieceCount[us][PAWN]--; - // Update piece lists - pieceList[us][piece][index[from]] = to; - index[to] = index[from]; + // Update material key + st->materialKey ^= zobrist[us][PAWN][pieceCount[us][PAWN]]; + st->materialKey ^= zobrist[us][promotion][pieceCount[us][promotion]-1]; - // Update castle rights - st->key ^= zobCastle[st->castleRights]; - st->castleRights &= castleRightsMask[from]; - st->castleRights &= castleRightsMask[to]; - st->key ^= zobCastle[st->castleRights]; + // Update piece lists, move the last pawn at index[to] position + // and shrink the list. Add a new promotion piece to the list. + Square lastPawnSquare = pieceList[us][PAWN][pieceCount[us][PAWN]]; + index[lastPawnSquare] = index[to]; + pieceList[us][PAWN][index[lastPawnSquare]] = lastPawnSquare; + pieceList[us][PAWN][pieceCount[us][PAWN]] = SQ_NONE; + index[to] = pieceCount[us][promotion] - 1; + pieceList[us][promotion][index[to]] = to; - // Update checkers bitboard, piece must be already moved - st->checkersBB = EmptyBoardBB; - Square ksq = king_square(them); - switch (piece) - { - case PAWN: update_checkers(&st->checkersBB, ksq, from, to, oldDcCandidates); break; - case KNIGHT: update_checkers(&st->checkersBB, ksq, from, to, oldDcCandidates); break; - case BISHOP: update_checkers(&st->checkersBB, ksq, from, to, oldDcCandidates); break; - case ROOK: update_checkers(&st->checkersBB, ksq, from, to, oldDcCandidates); break; - case QUEEN: update_checkers(&st->checkersBB, ksq, from, to, oldDcCandidates); break; - case KING: update_checkers(&st->checkersBB, ksq, from, to, oldDcCandidates); break; - default: assert(false); break; - } + // Partially revert hash keys update + key ^= zobrist[us][PAWN][to] ^ zobrist[us][promotion][to]; + st->pawnKey ^= zobrist[us][PAWN][to]; + + // Partially revert and update incremental scores + st->value -= pst(us, PAWN, to); + st->value += pst(us, promotion, to); + + // Update material + st->npMaterial[us] += PieceValueMidgame[promotion]; + } + } + + // Prefetch pawn and material hash tables + prefetchTables(st->pawnKey, st->materialKey, threadID); + + // Update incremental scores + st->value += pst_delta(piece, from, to); + + // Set capture piece + st->capturedType = capture; + + // Update the key with the final value + st->key = key; + + // Update checkers bitboard, piece must be already moved + st->checkersBB = EmptyBoardBB; + + if (moveIsCheck) + { + if (ep | pm) + st->checkersBB = attackers_to(king_square(them)) & pieces_of_color(us); + else + { + // Direct checks + if (bit_is_set(ci.checkSq[pt], to)) + st->checkersBB = SetMaskBB[to]; + + // Discovery checks + if (ci.dcCandidates && bit_is_set(ci.dcCandidates, from)) + { + if (pt != ROOK) + st->checkersBB |= (attacks_from(ci.ksq) & pieces(ROOK, QUEEN, us)); + + if (pt != BISHOP) + st->checkersBB |= (attacks_from(ci.ksq) & pieces(BISHOP, QUEEN, us)); + } + } } // Finish - find_pinned(); - st->key ^= zobSideToMove; sideToMove = opposite_color(sideToMove); - gamePly++; - - st->mgValue += (sideToMove == WHITE)? TempoValueMidgame : -TempoValueMidgame; - st->egValue += (sideToMove == WHITE)? TempoValueEndgame : -TempoValueEndgame; + st->value += (sideToMove == WHITE ? TempoValue : -TempoValue); assert(is_ok()); } @@ -838,40 +985,60 @@ void Position::do_move(Move m, StateInfo& newSt) { /// Position::do_capture_move() is a private method used to update captured /// piece info. It is called from the main Position::do_move function. -void Position::do_capture_move(Move m, PieceType capture, Color them, Square to) { +void Position::do_capture_move(Key& key, PieceType capture, Color them, Square to, bool ep) { assert(capture != KING); - // Remove captured piece - clear_bit(&(byColorBB[them]), to); - clear_bit(&(byTypeBB[capture]), to); - - // Update hash key - st->key ^= zobrist[them][capture][to]; + Square capsq = to; - // If the captured piece was a pawn, update pawn hash key + // If the captured piece was a pawn, update pawn hash key, + // otherwise update non-pawn material. if (capture == PAWN) - st->pawnKey ^= zobrist[them][PAWN][to]; + { + if (ep) // en passant ? + { + capsq = (them == BLACK)? (to - DELTA_N) : (to - DELTA_S); - // Update incremental scores - st->mgValue -= pst(them, capture, to); - st->egValue -= pst(them, capture, to); + assert(to == st->epSquare); + assert(relative_rank(opposite_color(them), to) == RANK_6); + assert(piece_on(to) == PIECE_NONE); + assert(piece_on(capsq) == make_piece(them, PAWN)); + + board[capsq] = PIECE_NONE; + } + st->pawnKey ^= zobrist[them][PAWN][capsq]; + } + else + st->npMaterial[them] -= PieceValueMidgame[capture]; - assert(!move_promotion(m) || capture != PAWN); + // Remove captured piece + clear_bit(&(byColorBB[them]), capsq); + clear_bit(&(byTypeBB[capture]), capsq); + clear_bit(&(byTypeBB[0]), capsq); - // Update material - if (capture != PAWN) - npMaterial[them] -= piece_value_midgame(capture); + // Update hash key + key ^= zobrist[them][capture][capsq]; - // Update material hash key - st->materialKey ^= zobMaterial[them][capture][pieceCount[them][capture]]; + // Update incremental scores + st->value -= pst(them, capture, capsq); // Update piece count pieceCount[them][capture]--; - // Update piece list - pieceList[them][capture][index[to]] = pieceList[them][capture][pieceCount[them][capture]]; - index[pieceList[them][capture][index[to]]] = index[to]; + // Update material hash key + st->materialKey ^= zobrist[them][capture][pieceCount[them][capture]]; + + // Update piece list, move the last piece at index[capsq] position + // + // WARNING: This is a not perfectly revresible operation. When we + // will reinsert the captured piece in undo_move() we will put it + // at the end of the list and not in its original place, it means + // index[] and pieceList[] are not guaranteed to be invariant to a + // do_move() + undo_move() sequence. + Square lastPieceSquare = pieceList[them][capture][pieceCount[them][capture]]; + index[lastPieceSquare] = index[capsq]; + pieceList[them][capture][index[lastPieceSquare]] = lastPieceSquare; + pieceList[them][capture][pieceCount[them][capture]] = SQ_NONE; // Reset rule 50 counter st->rule50 = 0; @@ -885,265 +1052,94 @@ void Position::do_capture_move(Move m, PieceType capture, Color them, Square to) void Position::do_castle_move(Move m) { - assert(is_ok()); assert(move_is_ok(m)); assert(move_is_castle(m)); Color us = side_to_move(); Color them = opposite_color(us); + // Reset capture field + st->capturedType = PIECE_TYPE_NONE; + // Find source squares for king and rook Square kfrom = move_from(m); Square rfrom = move_to(m); // HACK: See comment at beginning of function Square kto, rto; - assert(piece_on(kfrom) == piece_of_color_and_type(us, KING)); - assert(piece_on(rfrom) == piece_of_color_and_type(us, ROOK)); - - // Find destination squares for king and rook - if (rfrom > kfrom) // O-O - { - kto = relative_square(us, SQ_G1); - rto = relative_square(us, SQ_F1); - } else { // O-O-O - kto = relative_square(us, SQ_C1); - rto = relative_square(us, SQ_D1); - } - - // Remove pieces from source squares - clear_bit(&(byColorBB[us]), kfrom); - clear_bit(&(byTypeBB[KING]), kfrom); - clear_bit(&(byTypeBB[0]), kfrom); // HACK: byTypeBB[0] == occupied squares - clear_bit(&(byColorBB[us]), rfrom); - clear_bit(&(byTypeBB[ROOK]), rfrom); - clear_bit(&(byTypeBB[0]), rfrom); // HACK: byTypeBB[0] == occupied squares - - // Put pieces on destination squares - set_bit(&(byColorBB[us]), kto); - set_bit(&(byTypeBB[KING]), kto); - set_bit(&(byTypeBB[0]), kto); // HACK: byTypeBB[0] == occupied squares - set_bit(&(byColorBB[us]), rto); - set_bit(&(byTypeBB[ROOK]), rto); - set_bit(&(byTypeBB[0]), rto); // HACK: byTypeBB[0] == occupied squares - - // Update board array - board[kfrom] = board[rfrom] = EMPTY; - board[kto] = piece_of_color_and_type(us, KING); - board[rto] = piece_of_color_and_type(us, ROOK); - - // Update king square - kingSquare[us] = kto; + assert(piece_on(kfrom) == make_piece(us, KING)); + assert(piece_on(rfrom) == make_piece(us, ROOK)); - // Update piece lists - pieceList[us][KING][index[kfrom]] = kto; - pieceList[us][ROOK][index[rfrom]] = rto; - int tmp = index[rfrom]; - index[kto] = index[kfrom]; - index[rto] = tmp; - - // Update incremental scores - st->mgValue -= pst(us, KING, kfrom); - st->mgValue += pst(us, KING, kto); - st->egValue -= pst(us, KING, kfrom); - st->egValue += pst(us, KING, kto); - st->mgValue -= pst(us, ROOK, rfrom); - st->mgValue += pst(us, ROOK, rto); - st->egValue -= pst(us, ROOK, rfrom); - st->egValue += pst(us, ROOK, rto); - - // Update hash key - st->key ^= zobrist[us][KING][kfrom] ^ zobrist[us][KING][kto]; - st->key ^= zobrist[us][ROOK][rfrom] ^ zobrist[us][ROOK][rto]; - - // Clear en passant square - if (st->epSquare != SQ_NONE) - { - st->key ^= zobEp[st->epSquare]; - st->epSquare = SQ_NONE; - } - - // Update castling rights - st->key ^= zobCastle[st->castleRights]; - st->castleRights &= castleRightsMask[kfrom]; - st->key ^= zobCastle[st->castleRights]; - - // Reset rule 50 counter - st->rule50 = 0; - - // Update checkers BB - st->checkersBB = attacks_to(king_square(them), us); -} - - -/// Position::do_promotion_move() is a private method used to make a promotion -/// move. It is called from the main Position::do_move function. - -void Position::do_promotion_move(Move m) { - - Color us, them; - Square from, to; - PieceType promotion; - - assert(is_ok()); - assert(move_is_ok(m)); - assert(move_promotion(m)); - - us = side_to_move(); - them = opposite_color(us); - from = move_from(m); - to = move_to(m); - - assert(relative_rank(us, to) == RANK_8); - assert(piece_on(from) == piece_of_color_and_type(us, PAWN)); - assert(color_of_piece_on(to) == them || square_is_empty(to)); - - st->capture = type_of_piece_on(to); - - if (st->capture) - do_capture_move(m, st->capture, them, to); - - // Remove pawn - clear_bit(&(byColorBB[us]), from); - clear_bit(&(byTypeBB[PAWN]), from); - clear_bit(&(byTypeBB[0]), from); // HACK: byTypeBB[0] == occupied squares - board[from] = EMPTY; - - // Insert promoted piece - promotion = move_promotion(m); - assert(promotion >= KNIGHT && promotion <= QUEEN); - set_bit(&(byColorBB[us]), to); - set_bit(&(byTypeBB[promotion]), to); - set_bit(&(byTypeBB[0]), to); // HACK: byTypeBB[0] == occupied squares - board[to] = piece_of_color_and_type(us, promotion); - - // Update hash key - st->key ^= zobrist[us][PAWN][from] ^ zobrist[us][promotion][to]; + // Find destination squares for king and rook + if (rfrom > kfrom) // O-O + { + kto = relative_square(us, SQ_G1); + rto = relative_square(us, SQ_F1); + } else { // O-O-O + kto = relative_square(us, SQ_C1); + rto = relative_square(us, SQ_D1); + } - // Update pawn hash key - st->pawnKey ^= zobrist[us][PAWN][from]; + // Remove pieces from source squares: + clear_bit(&(byColorBB[us]), kfrom); + clear_bit(&(byTypeBB[KING]), kfrom); + clear_bit(&(byTypeBB[0]), kfrom); // HACK: byTypeBB[0] == occupied squares + clear_bit(&(byColorBB[us]), rfrom); + clear_bit(&(byTypeBB[ROOK]), rfrom); + clear_bit(&(byTypeBB[0]), rfrom); // HACK: byTypeBB[0] == occupied squares - // Update material key - st->materialKey ^= zobMaterial[us][PAWN][pieceCount[us][PAWN]]; - st->materialKey ^= zobMaterial[us][promotion][pieceCount[us][promotion]+1]; + // Put pieces on destination squares: + set_bit(&(byColorBB[us]), kto); + set_bit(&(byTypeBB[KING]), kto); + set_bit(&(byTypeBB[0]), kto); // HACK: byTypeBB[0] == occupied squares + set_bit(&(byColorBB[us]), rto); + set_bit(&(byTypeBB[ROOK]), rto); + set_bit(&(byTypeBB[0]), rto); // HACK: byTypeBB[0] == occupied squares - // Update piece counts - pieceCount[us][PAWN]--; - pieceCount[us][promotion]++; + // Update board array + Piece king = make_piece(us, KING); + Piece rook = make_piece(us, ROOK); + board[kfrom] = board[rfrom] = PIECE_NONE; + board[kto] = king; + board[rto] = rook; // Update piece lists - pieceList[us][PAWN][index[from]] = pieceList[us][PAWN][pieceCount[us][PAWN]]; - index[pieceList[us][PAWN][index[from]]] = index[from]; - pieceList[us][promotion][pieceCount[us][promotion] - 1] = to; - index[to] = pieceCount[us][promotion] - 1; + pieceList[us][KING][index[kfrom]] = kto; + pieceList[us][ROOK][index[rfrom]] = rto; + int tmp = index[rfrom]; // In Chess960 could be rto == kfrom + index[kto] = index[kfrom]; + index[rto] = tmp; // Update incremental scores - st->mgValue -= pst(us, PAWN, from); - st->mgValue += pst(us, promotion, to); - st->egValue -= pst(us, PAWN, from); - st->egValue += pst(us, promotion, to); + st->value += pst_delta(king, kfrom, kto); + st->value += pst_delta(rook, rfrom, rto); - // Update material - npMaterial[us] += piece_value_midgame(promotion); + // Update hash key + st->key ^= zobrist[us][KING][kfrom] ^ zobrist[us][KING][kto]; + st->key ^= zobrist[us][ROOK][rfrom] ^ zobrist[us][ROOK][rto]; - // Clear the en passant square + // Clear en passant square if (st->epSquare != SQ_NONE) { st->key ^= zobEp[st->epSquare]; st->epSquare = SQ_NONE; } - // Update castle rights + // Update castling rights st->key ^= zobCastle[st->castleRights]; - st->castleRights &= castleRightsMask[to]; + st->castleRights &= castleRightsMask[kfrom]; st->key ^= zobCastle[st->castleRights]; // Reset rule 50 counter st->rule50 = 0; // Update checkers BB - st->checkersBB = attacks_to(king_square(them), us); -} - - -/// Position::do_ep_move() is a private method used to make an en passant -/// capture. It is called from the main Position::do_move function. - -void Position::do_ep_move(Move m) { + st->checkersBB = attackers_to(king_square(them)) & pieces_of_color(us); - Color us, them; - Square from, to, capsq; + // Finish + sideToMove = opposite_color(sideToMove); + st->value += (sideToMove == WHITE ? TempoValue : -TempoValue); assert(is_ok()); - assert(move_is_ok(m)); - assert(move_is_ep(m)); - - us = side_to_move(); - them = opposite_color(us); - from = move_from(m); - to = move_to(m); - capsq = (us == WHITE)? (to - DELTA_N) : (to - DELTA_S); - - assert(to == st->epSquare); - assert(relative_rank(us, to) == RANK_6); - assert(piece_on(to) == EMPTY); - assert(piece_on(from) == piece_of_color_and_type(us, PAWN)); - assert(piece_on(capsq) == piece_of_color_and_type(them, PAWN)); - - // Remove captured piece - clear_bit(&(byColorBB[them]), capsq); - clear_bit(&(byTypeBB[PAWN]), capsq); - clear_bit(&(byTypeBB[0]), capsq); // HACK: byTypeBB[0] == occupied squares - board[capsq] = EMPTY; - - // Remove moving piece from source square - clear_bit(&(byColorBB[us]), from); - clear_bit(&(byTypeBB[PAWN]), from); - clear_bit(&(byTypeBB[0]), from); // HACK: byTypeBB[0] == occupied squares - - // Put moving piece on destination square - set_bit(&(byColorBB[us]), to); - set_bit(&(byTypeBB[PAWN]), to); - set_bit(&(byTypeBB[0]), to); // HACK: byTypeBB[0] == occupied squares - board[to] = board[from]; - board[from] = EMPTY; - - // Update material hash key - st->materialKey ^= zobMaterial[them][PAWN][pieceCount[them][PAWN]]; - - // Update piece count - pieceCount[them][PAWN]--; - - // Update piece list - pieceList[us][PAWN][index[from]] = to; - index[to] = index[from]; - pieceList[them][PAWN][index[capsq]] = pieceList[them][PAWN][pieceCount[them][PAWN]]; - index[pieceList[them][PAWN][index[capsq]]] = index[capsq]; - - // Update hash key - st->key ^= zobrist[us][PAWN][from] ^ zobrist[us][PAWN][to]; - st->key ^= zobrist[them][PAWN][capsq]; - st->key ^= zobEp[st->epSquare]; - - // Update pawn hash key - st->pawnKey ^= zobrist[us][PAWN][from] ^ zobrist[us][PAWN][to]; - st->pawnKey ^= zobrist[them][PAWN][capsq]; - - // Update incremental scores - st->mgValue -= pst(them, PAWN, capsq); - st->mgValue -= pst(us, PAWN, from); - st->mgValue += pst(us, PAWN, to); - st->egValue -= pst(them, PAWN, capsq); - st->egValue -= pst(us, PAWN, from); - st->egValue += pst(us, PAWN, to); - - // Reset en passant square - st->epSquare = SQ_NONE; - - // Reset rule 50 counter - st->rule50 = 0; - - // Update checkers BB - st->checkersBB = attacks_to(king_square(them), us); } @@ -1155,74 +1151,94 @@ void Position::undo_move(Move m) { assert(is_ok()); assert(move_is_ok(m)); - gamePly--; sideToMove = opposite_color(sideToMove); if (move_is_castle(m)) + { undo_castle_move(m); - else if (move_promotion(m)) - undo_promotion_move(m); - else if (move_is_ep(m)) - undo_ep_move(m); - else + return; + } + + Color us = side_to_move(); + Color them = opposite_color(us); + Square from = move_from(m); + Square to = move_to(m); + bool ep = move_is_ep(m); + bool pm = move_is_promotion(m); + + PieceType pt = type_of_piece_on(to); + + assert(square_is_empty(from)); + assert(color_of_piece_on(to) == us); + assert(!pm || relative_rank(us, to) == RANK_8); + assert(!ep || to == st->previous->epSquare); + assert(!ep || relative_rank(us, to) == RANK_6); + assert(!ep || piece_on(to) == make_piece(us, PAWN)); + + if (pm) // promotion ? { - Color us, them; - Square from, to; - PieceType piece; - - us = side_to_move(); - them = opposite_color(us); - from = move_from(m); - to = move_to(m); - - assert(piece_on(from) == EMPTY); - assert(color_of_piece_on(to) == us); - - // Put the piece back at the source square - piece = type_of_piece_on(to); - set_bit(&(byColorBB[us]), from); - set_bit(&(byTypeBB[piece]), from); - set_bit(&(byTypeBB[0]), from); // HACK: byTypeBB[0] == occupied squares - board[from] = piece_of_color_and_type(us, piece); - - // Clear the destination square - clear_bit(&(byColorBB[us]), to); - clear_bit(&(byTypeBB[piece]), to); - clear_bit(&(byTypeBB[0]), to); // HACK: byTypeBB[0] == occupied squares - - // If the moving piece was a king, update the king square - if (piece == KING) - kingSquare[us] = from; - - // Update piece list - pieceList[us][piece][index[to]] = from; - index[from] = index[to]; - - if (st->capture) - { - assert(st->capture != KING); + PieceType promotion = move_promotion_piece(m); + pt = PAWN; + + assert(promotion >= KNIGHT && promotion <= QUEEN); + assert(piece_on(to) == make_piece(us, promotion)); + + // Replace promoted piece with a pawn + clear_bit(&(byTypeBB[promotion]), to); + set_bit(&(byTypeBB[PAWN]), to); + + // Update piece counts + pieceCount[us][promotion]--; + pieceCount[us][PAWN]++; + + // Update piece list replacing promotion piece with a pawn + Square lastPromotionSquare = pieceList[us][promotion][pieceCount[us][promotion]]; + index[lastPromotionSquare] = index[to]; + pieceList[us][promotion][index[lastPromotionSquare]] = lastPromotionSquare; + pieceList[us][promotion][pieceCount[us][promotion]] = SQ_NONE; + index[to] = pieceCount[us][PAWN] - 1; + pieceList[us][PAWN][index[to]] = to; + } - // Replace the captured piece - set_bit(&(byColorBB[them]), to); - set_bit(&(byTypeBB[st->capture]), to); - set_bit(&(byTypeBB[0]), to); - board[to] = piece_of_color_and_type(them, st->capture); + // Put the piece back at the source square + Bitboard move_bb = make_move_bb(to, from); + do_move_bb(&(byColorBB[us]), move_bb); + do_move_bb(&(byTypeBB[pt]), move_bb); + do_move_bb(&(byTypeBB[0]), move_bb); // HACK: byTypeBB[0] == occupied squares - // Update material - if (st->capture != PAWN) - npMaterial[them] += piece_value_midgame(st->capture); + board[from] = make_piece(us, pt); + board[to] = PIECE_NONE; + + // Update piece list + index[from] = index[to]; + pieceList[us][pt][index[from]] = from; + + if (st->capturedType) + { + Square capsq = to; + + if (ep) + capsq = (us == WHITE)? (to - DELTA_N) : (to - DELTA_S); + + assert(st->capturedType != KING); + assert(!ep || square_is_empty(capsq)); + + // Restore the captured piece + set_bit(&(byColorBB[them]), capsq); + set_bit(&(byTypeBB[st->capturedType]), capsq); + set_bit(&(byTypeBB[0]), capsq); - // Update piece list - pieceList[them][st->capture][pieceCount[them][st->capture]] = to; - index[to] = pieceCount[them][st->capture]; + board[capsq] = make_piece(them, st->capturedType); - // Update piece count - pieceCount[them][st->capture]++; - } else - board[to] = EMPTY; + // Update piece count + pieceCount[them][st->capturedType]++; + + // Update piece list, add a new captured piece in capsq square + index[capsq] = pieceCount[them][st->capturedType] - 1; + pieceList[them][st->capturedType][index[capsq]] = capsq; } - // Finally point out state pointer back to the previous state + // Finally point our state pointer back to the previous state st = st->previous; assert(is_ok()); @@ -1259,10 +1275,10 @@ void Position::undo_castle_move(Move m) { rto = relative_square(us, SQ_D1); } - assert(piece_on(kto) == piece_of_color_and_type(us, KING)); - assert(piece_on(rto) == piece_of_color_and_type(us, ROOK)); + assert(piece_on(kto) == make_piece(us, KING)); + assert(piece_on(rto) == make_piece(us, ROOK)); - // Remove pieces from destination squares + // Remove pieces from destination squares: clear_bit(&(byColorBB[us]), kto); clear_bit(&(byTypeBB[KING]), kto); clear_bit(&(byTypeBB[0]), kto); // HACK: byTypeBB[0] == occupied squares @@ -1270,7 +1286,7 @@ void Position::undo_castle_move(Move m) { clear_bit(&(byTypeBB[ROOK]), rto); clear_bit(&(byTypeBB[0]), rto); // HACK: byTypeBB[0] == occupied squares - // Put pieces on source squares + // Put pieces on source squares: set_bit(&(byColorBB[us]), kfrom); set_bit(&(byTypeBB[KING]), kfrom); set_bit(&(byTypeBB[0]), kfrom); // HACK: byTypeBB[0] == occupied squares @@ -1279,186 +1295,59 @@ void Position::undo_castle_move(Move m) { set_bit(&(byTypeBB[0]), rfrom); // HACK: byTypeBB[0] == occupied squares // Update board - board[rto] = board[kto] = EMPTY; - board[rfrom] = piece_of_color_and_type(us, ROOK); - board[kfrom] = piece_of_color_and_type(us, KING); - - // Update king square - kingSquare[us] = kfrom; + board[rto] = board[kto] = PIECE_NONE; + board[rfrom] = make_piece(us, ROOK); + board[kfrom] = make_piece(us, KING); // Update piece lists pieceList[us][KING][index[kto]] = kfrom; pieceList[us][ROOK][index[rto]] = rfrom; - int tmp = index[rto]; // Necessary because we may have rto == kfrom in FRC. + int tmp = index[rto]; // In Chess960 could be rto == kfrom index[kfrom] = index[kto]; index[rfrom] = tmp; -} - - -/// Position::undo_promotion_move() is a private method used to unmake a -/// promotion move. It is called from the main Position::do_move -/// function. - -void Position::undo_promotion_move(Move m) { - - Color us, them; - Square from, to; - PieceType promotion; - - assert(move_is_ok(m)); - assert(move_promotion(m)); - - // When we have arrived here, some work has already been done by - // Position::undo_move. In particular, the side to move has been switched, - // so the code below is correct. - us = side_to_move(); - them = opposite_color(us); - from = move_from(m); - to = move_to(m); - - assert(relative_rank(us, to) == RANK_8); - assert(piece_on(from) == EMPTY); - - // Remove promoted piece - promotion = move_promotion(m); - assert(piece_on(to)==piece_of_color_and_type(us, promotion)); - assert(promotion >= KNIGHT && promotion <= QUEEN); - clear_bit(&(byColorBB[us]), to); - clear_bit(&(byTypeBB[promotion]), to); - clear_bit(&(byTypeBB[0]), to); // HACK: byTypeBB[0] == occupied squares - - // Insert pawn at source square - set_bit(&(byColorBB[us]), from); - set_bit(&(byTypeBB[PAWN]), from); - set_bit(&(byTypeBB[0]), from); // HACK: byTypeBB[0] == occupied squares - board[from] = piece_of_color_and_type(us, PAWN); - - // Update material - npMaterial[us] -= piece_value_midgame(promotion); - - // Update piece list - pieceList[us][PAWN][pieceCount[us][PAWN]] = from; - index[from] = pieceCount[us][PAWN]; - pieceList[us][promotion][index[to]] = - pieceList[us][promotion][pieceCount[us][promotion] - 1]; - index[pieceList[us][promotion][index[to]]] = index[to]; - // Update piece counts - pieceCount[us][promotion]--; - pieceCount[us][PAWN]++; - - if (st->capture) - { - assert(st->capture != KING); - - // Insert captured piece: - set_bit(&(byColorBB[them]), to); - set_bit(&(byTypeBB[st->capture]), to); - set_bit(&(byTypeBB[0]), to); // HACK: byTypeBB[0] == occupied squares - board[to] = piece_of_color_and_type(them, st->capture); - - // Update material. Because the move is a promotion move, we know - // that the captured piece cannot be a pawn. - assert(st->capture != PAWN); - npMaterial[them] += piece_value_midgame(st->capture); - - // Update piece list - pieceList[them][st->capture][pieceCount[them][st->capture]] = to; - index[to] = pieceCount[them][st->capture]; - - // Update piece count - pieceCount[them][st->capture]++; - } else - board[to] = EMPTY; -} - - -/// Position::undo_ep_move() is a private method used to unmake an en passant -/// capture. It is called from the main Position::undo_move function. - -void Position::undo_ep_move(Move m) { - - assert(move_is_ok(m)); - assert(move_is_ep(m)); - - // When we have arrived here, some work has already been done by - // Position::undo_move. In particular, the side to move has been switched, - // so the code below is correct. - Color us = side_to_move(); - Color them = opposite_color(us); - Square from = move_from(m); - Square to = move_to(m); - Square capsq = (us == WHITE)? (to - DELTA_N) : (to - DELTA_S); - - assert(to == st->previous->epSquare); - assert(relative_rank(us, to) == RANK_6); - assert(piece_on(to) == piece_of_color_and_type(us, PAWN)); - assert(piece_on(from) == EMPTY); - assert(piece_on(capsq) == EMPTY); - - // Replace captured piece - set_bit(&(byColorBB[them]), capsq); - set_bit(&(byTypeBB[PAWN]), capsq); - set_bit(&(byTypeBB[0]), capsq); - board[capsq] = piece_of_color_and_type(them, PAWN); - - // Remove moving piece from destination square - clear_bit(&(byColorBB[us]), to); - clear_bit(&(byTypeBB[PAWN]), to); - clear_bit(&(byTypeBB[0]), to); - board[to] = EMPTY; - - // Replace moving piece at source square - set_bit(&(byColorBB[us]), from); - set_bit(&(byTypeBB[PAWN]), from); - set_bit(&(byTypeBB[0]), from); - board[from] = piece_of_color_and_type(us, PAWN); - - // Update piece list: - pieceList[us][PAWN][index[to]] = from; - index[from] = index[to]; - pieceList[them][PAWN][pieceCount[them][PAWN]] = capsq; - index[capsq] = pieceCount[them][PAWN]; + // Finally point our state pointer back to the previous state + st = st->previous; - // Update piece count: - pieceCount[them][PAWN]++; + assert(is_ok()); } /// Position::do_null_move makes() a "null move": It switches the side to move /// and updates the hash key without executing any move on the board. -void Position::do_null_move(StateInfo& newSt) { +void Position::do_null_move(StateInfo& backupSt) { assert(is_ok()); assert(!is_check()); // Back up the information necessary to undo the null move to the supplied - // StateInfo object. In the case of a null move, the only thing we need to - // remember is the last move made and the en passant square. - newSt.lastMove = st->lastMove; - newSt.epSquare = st->epSquare; - newSt.previous = st->previous; - st->previous = &newSt; + // StateInfo object. + // Note that differently from normal case here backupSt is actually used as + // a backup storage not as a new state to be used. + backupSt.key = st->key; + backupSt.epSquare = st->epSquare; + backupSt.value = st->value; + backupSt.previous = st->previous; + backupSt.pliesFromNull = st->pliesFromNull; + st->previous = &backupSt; // Save the current key to the history[] array, in order to be able to // detect repetition draws. - history[gamePly] = st->key; + history[st->gamePly++] = st->key; // Update the necessary information - sideToMove = opposite_color(sideToMove); if (st->epSquare != SQ_NONE) st->key ^= zobEp[st->epSquare]; - st->epSquare = SQ_NONE; - st->rule50++; - gamePly++; st->key ^= zobSideToMove; + prefetch((char*)TT.first_entry(st->key)); - st->mgValue += (sideToMove == WHITE)? TempoValueMidgame : -TempoValueMidgame; - st->egValue += (sideToMove == WHITE)? TempoValueEndgame : -TempoValueEndgame; - - assert(is_ok()); + sideToMove = opposite_color(sideToMove); + st->epSquare = SQ_NONE; + st->rule50++; + st->pliesFromNull = 0; + st->value += (sideToMove == WHITE) ? TempoValue : -TempoValue; } @@ -1469,119 +1358,95 @@ void Position::undo_null_move() { assert(is_ok()); assert(!is_check()); - // Restore information from the our StateInfo object - st->lastMove = st->previous->lastMove; - st->epSquare = st->previous->epSquare; - st->previous = st->previous->previous; - - if (st->epSquare != SQ_NONE) - st->key ^= zobEp[st->epSquare]; + // Restore information from the our backup StateInfo object + StateInfo* backupSt = st->previous; + st->key = backupSt->key; + st->epSquare = backupSt->epSquare; + st->value = backupSt->value; + st->previous = backupSt->previous; + st->pliesFromNull = backupSt->pliesFromNull; // Update the necessary information sideToMove = opposite_color(sideToMove); st->rule50--; - gamePly--; - st->key ^= zobSideToMove; - - st->mgValue += (sideToMove == WHITE)? TempoValueMidgame : -TempoValueMidgame; - st->egValue += (sideToMove == WHITE)? TempoValueEndgame : -TempoValueEndgame; - - assert(is_ok()); + st->gamePly--; } /// Position::see() is a static exchange evaluator: It tries to estimate the -/// material gain or loss resulting from a move. There are three versions of +/// material gain or loss resulting from a move. There are three versions of /// this function: One which takes a destination square as input, one takes a /// move, and one which takes a 'from' and a 'to' square. The function does /// not yet understand promotions captures. -int Position::see(Square to) const { +int Position::see(Move m) const { - assert(square_is_ok(to)); - return see(SQ_NONE, to); + assert(move_is_ok(m)); + return see(move_from(m), move_to(m)); } -int Position::see(Move m) const { +int Position::see_sign(Move m) const { assert(move_is_ok(m)); - return see(move_from(m), move_to(m)); + + Square from = move_from(m); + Square to = move_to(m); + + // Early return if SEE cannot be negative because captured piece value + // is not less then capturing one. Note that king moves always return + // here because king midgame value is set to 0. + if (midgame_value_of_piece_on(to) >= midgame_value_of_piece_on(from)) + return 1; + + return see(from, to); } int Position::see(Square from, Square to) const { - // Material values - static const int seeValues[18] = { - 0, PawnValueMidgame, KnightValueMidgame, BishopValueMidgame, - RookValueMidgame, QueenValueMidgame, QueenValueMidgame*10, 0, - 0, PawnValueMidgame, KnightValueMidgame, BishopValueMidgame, - RookValueMidgame, QueenValueMidgame, QueenValueMidgame*10, 0, - 0, 0 - }; - - Bitboard attackers, occ, b; + Bitboard occupied, attackers, stmAttackers, b; + int swapList[32], slIndex = 1; + PieceType capturedType, pt; + Color stm; - assert(square_is_ok(from) || from == SQ_NONE); + assert(square_is_ok(from)); assert(square_is_ok(to)); - // Initialize colors - Color us = (from != SQ_NONE ? color_of_piece_on(from) : opposite_color(color_of_piece_on(to))); - Color them = opposite_color(us); + capturedType = type_of_piece_on(to); - // Initialize pieces - Piece piece = piece_on(from); - Piece capture = piece_on(to); + // King cannot be recaptured + if (capturedType == KING) + return seeValues[capturedType]; - // Find all attackers to the destination square, with the moving piece - // removed, but possibly an X-ray attacker added behind it. - occ = occupied_squares(); + occupied = occupied_squares(); // Handle en passant moves if (st->epSquare == to && type_of_piece_on(from) == PAWN) { - assert(capture == EMPTY); - - Square capQq = (side_to_move() == WHITE)? (to - DELTA_N) : (to - DELTA_S); - capture = piece_on(capQq); + Square capQq = (side_to_move() == WHITE ? to - DELTA_N : to - DELTA_S); + assert(capturedType == PIECE_TYPE_NONE); assert(type_of_piece_on(capQq) == PAWN); // Remove the captured pawn - clear_bit(&occ, capQq); + clear_bit(&occupied, capQq); + capturedType = PAWN; } - while (true) - { - clear_bit(&occ, from); - attackers = (rook_attacks_bb(to, occ) & rooks_and_queens()) - | (bishop_attacks_bb(to, occ) & bishops_and_queens()) - | (piece_attacks(to) & knights()) - | (piece_attacks(to) & kings()) - | (pawn_attacks(WHITE, to) & pawns(BLACK)) - | (pawn_attacks(BLACK, to) & pawns(WHITE)); - - if (from != SQ_NONE) - break; - - // If we don't have any attacker we are finished - if ((attackers & pieces_of_color(us)) == EmptyBoardBB) - return 0; - - // Locate the least valuable attacker to the destination square - // and use it to initialize from square. - PieceType pt; - for (pt = PAWN; !(attackers & pieces_of_color_and_type(us, pt)); pt++) - assert(pt < KING); - - from = first_1(attackers & pieces_of_color_and_type(us, pt)); - piece = piece_on(from); - } + // Find all attackers to the destination square, with the moving piece + // removed, but possibly an X-ray attacker added behind it. + clear_bit(&occupied, from); + attackers = (rook_attacks_bb(to, occupied) & pieces(ROOK, QUEEN)) + | (bishop_attacks_bb(to, occupied)& pieces(BISHOP, QUEEN)) + | (attacks_from(to) & pieces(KNIGHT)) + | (attacks_from(to) & pieces(KING)) + | (attacks_from(to, WHITE) & pieces(PAWN, BLACK)) + | (attacks_from(to, BLACK) & pieces(PAWN, WHITE)); // If the opponent has no attackers we are finished - if ((attackers & pieces_of_color(them)) == EmptyBoardBB) - return seeValues[capture]; - - attackers &= occ; // Remove the moving piece + stm = opposite_color(color_of_piece_on(from)); + stmAttackers = attackers & pieces_of_color(stm); + if (!stmAttackers) + return seeValues[capturedType]; // The destination square is defended, which makes things rather more // difficult to compute. We proceed by building up a "swap list" containing @@ -1589,52 +1454,49 @@ int Position::see(Square from, Square to) const { // destination square, where the sides alternately capture, and always // capture with the least valuable piece. After each capture, we look for // new X-ray attacks from behind the capturing piece. - int lastCapturingPieceValue = seeValues[piece]; - int swapList[32], n = 1; - Color c = them; - PieceType pt; - - swapList[0] = seeValues[capture]; + swapList[0] = seeValues[capturedType]; + capturedType = type_of_piece_on(from); do { - // Locate the least valuable attacker for the side to move. The loop + // Locate the least valuable attacker for the side to move. The loop // below looks like it is potentially infinite, but it isn't. We know // that the side to move still has at least one attacker left. - for (pt = PAWN; !(attackers & pieces_of_color_and_type(c, pt)); pt++) + for (pt = PAWN; !(stmAttackers & pieces(pt)); pt++) assert(pt < KING); - // Remove the attacker we just found from the 'attackers' bitboard, + // Remove the attacker we just found from the 'occupied' bitboard, // and scan for new X-ray attacks behind the attacker. - b = attackers & pieces_of_color_and_type(c, pt); - occ ^= (b & -b); - attackers |= (rook_attacks_bb(to, occ) & rooks_and_queens()) - | (bishop_attacks_bb(to, occ) & bishops_and_queens()); + b = stmAttackers & pieces(pt); + occupied ^= (b & (~b + 1)); + attackers |= (rook_attacks_bb(to, occupied) & pieces(ROOK, QUEEN)) + | (bishop_attacks_bb(to, occupied) & pieces(BISHOP, QUEEN)); - attackers &= occ; + attackers &= occupied; // Cut out pieces we've already done // Add the new entry to the swap list - assert(n < 32); - swapList[n] = -swapList[n - 1] + lastCapturingPieceValue; - n++; - - // Remember the value of the capturing piece, and change the side to move - // before beginning the next iteration - lastCapturingPieceValue = seeValues[pt]; - c = opposite_color(c); - - // Stop after a king capture - if (pt == KING && (attackers & pieces_of_color(c))) + assert(slIndex < 32); + swapList[slIndex] = -swapList[slIndex - 1] + seeValues[capturedType]; + slIndex++; + + // Remember the value of the capturing piece, and change the side to + // move before beginning the next iteration. + capturedType = pt; + stm = opposite_color(stm); + stmAttackers = attackers & pieces_of_color(stm); + + // Stop before processing a king capture + if (capturedType == KING && stmAttackers) { - assert(n < 32); - swapList[n++] = 100; + assert(slIndex < 32); + swapList[slIndex++] = QueenValueMidgame*10; break; } - } while (attackers & pieces_of_color(c)); + } while (stmAttackers); // Having built the swap list, we negamax through it to find the best - // achievable score from the point of view of the side to move - while (--n) - swapList[n-1] = Min(-swapList[n], swapList[n-1]); + // achievable score from the point of view of the side to move. + while (--slIndex) + swapList[slIndex-1] = Min(-swapList[slIndex], swapList[slIndex-1]); return swapList[0]; } @@ -1648,43 +1510,33 @@ void Position::clear() { st = &startState; memset(st, 0, sizeof(StateInfo)); st->epSquare = SQ_NONE; + startPosPlyCounter = 0; + nodes = 0; - memset(index, 0, sizeof(int) * 64); - memset(byColorBB, 0, sizeof(Bitboard) * 2); + memset(byColorBB, 0, sizeof(Bitboard) * 2); + memset(byTypeBB, 0, sizeof(Bitboard) * 8); + memset(pieceCount, 0, sizeof(int) * 2 * 8); + memset(index, 0, sizeof(int) * 64); for (int i = 0; i < 64; i++) - board[i] = EMPTY; + board[i] = PIECE_NONE; - for (int i = 0; i < 7; i++) - { - byTypeBB[i] = EmptyBoardBB; - pieceCount[0][i] = pieceCount[1][i] = 0; - for (int j = 0; j < 8; j++) + for (int i = 0; i < 8; i++) + for (int j = 0; j < 16; j++) pieceList[0][i][j] = pieceList[1][i][j] = SQ_NONE; - } + + for (Square sq = SQ_A1; sq <= SQ_H8; sq++) + castleRightsMask[sq] = ALL_CASTLES; sideToMove = WHITE; - gamePly = 0; initialKFile = FILE_E; initialKRFile = FILE_H; initialQRFile = FILE_A; } -/// Position::reset_game_ply() simply sets gamePly to 0. It is used from the -/// UCI interface code, whenever a non-reversible move is made in a -/// 'position fen moves m1 m2 ...' command. This makes it possible -/// for the program to handle games of arbitrary length, as long as the GUI -/// handles draws by the 50 move rule correctly. - -void Position::reset_game_ply() { - - gamePly = 0; -} - - /// Position::put_piece() puts a piece on the given square of the board, -/// updating the board array, bitboards, and piece counts. +/// updating the board array, pieces list, bitboards, and piece counts. void Position::put_piece(Piece p, Square s) { @@ -1692,35 +1544,12 @@ void Position::put_piece(Piece p, Square s) { PieceType pt = type_of_piece(p); board[s] = p; - index[s] = pieceCount[c][pt]; + index[s] = pieceCount[c][pt]++; pieceList[c][pt][index[s]] = s; set_bit(&(byTypeBB[pt]), s); set_bit(&(byColorBB[c]), s); - set_bit(&byTypeBB[0], s); // HACK: byTypeBB[0] contains all occupied squares. - - pieceCount[c][pt]++; - - if (pt == KING) - kingSquare[c] = s; -} - - -/// Position::allow_oo() gives the given side the right to castle kingside. -/// Used when setting castling rights during parsing of FEN strings. - -void Position::allow_oo(Color c) { - - st->castleRights |= (1 + int(c)); -} - - -/// Position::allow_ooo() gives the given side the right to castle queenside. -/// Used when setting castling rights during parsing of FEN strings. - -void Position::allow_ooo(Color c) { - - st->castleRights |= (4 + 4*int(c)); + set_bit(&(byTypeBB[0]), s); // HACK: byTypeBB[0] contains all occupied squares. } @@ -1731,7 +1560,7 @@ void Position::allow_ooo(Color c) { Key Position::compute_key() const { - Key result = Key(0ULL); + Key result = zobCastle[st->castleRights]; for (Square s = SQ_A1; s <= SQ_H8; s++) if (square_is_occupied(s)) @@ -1740,7 +1569,6 @@ Key Position::compute_key() const { if (ep_square() != SQ_NONE) result ^= zobEp[ep_square()]; - result ^= zobCastle[st->castleRights]; if (side_to_move() == BLACK) result ^= zobSideToMove; @@ -1756,18 +1584,14 @@ Key Position::compute_key() const { Key Position::compute_pawn_key() const { - Key result = Key(0ULL); Bitboard b; - Square s; + Key result = 0; for (Color c = WHITE; c <= BLACK; c++) { - b = pawns(c); - while(b) - { - s = pop_1st_bit(&b); - result ^= zobrist[c][PAWN][s]; - } + b = pieces(PAWN, c); + while (b) + result ^= zobrist[c][PAWN][pop_1st_bit(&b)]; } return result; } @@ -1781,13 +1605,15 @@ Key Position::compute_pawn_key() const { Key Position::compute_material_key() const { - Key result = Key(0ULL); + int count; + Key result = 0; + for (Color c = WHITE; c <= BLACK; c++) for (PieceType pt = PAWN; pt <= QUEEN; pt++) { - int count = piece_count(c, pt); - for (int i = 0; i <= count; i++) - result ^= zobMaterial[c][pt][i]; + count = piece_count(c, pt); + for (int i = 0; i < count; i++) + result ^= zobrist[c][pt][i]; } return result; } @@ -1797,67 +1623,37 @@ Key Position::compute_material_key() const { /// game and the endgame. These functions are used to initialize the incremental /// scores when a new position is set up, and to verify that the scores are correctly /// updated by do_move and undo_move when the program is running in debug mode. -template -Value Position::compute_value() const { +Score Position::compute_value() const { - Value result = Value(0); Bitboard b; - Square s; + Score result = SCORE_ZERO; for (Color c = WHITE; c <= BLACK; c++) for (PieceType pt = PAWN; pt <= KING; pt++) { - b = pieces_of_color_and_type(c, pt); - while(b) - { - s = pop_1st_bit(&b); - assert(piece_on(s) == piece_of_color_and_type(c, pt)); - result += pst(c, pt, s); - } + b = pieces(pt, c); + while (b) + result += pst(c, pt, pop_1st_bit(&b)); } - const Value TempoValue = (Phase == MidGame ? TempoValueMidgame : TempoValueEndgame); - result += (side_to_move() == WHITE)? TempoValue / 2 : -TempoValue / 2; + result += (side_to_move() == WHITE ? TempoValue / 2 : -TempoValue / 2); return result; } /// Position::compute_non_pawn_material() computes the total non-pawn middle -/// game material score for the given side. Material scores are updated +/// game material value for the given side. Material values are updated /// incrementally during the search, this function is only used while /// initializing a new Position object. Value Position::compute_non_pawn_material(Color c) const { - Value result = Value(0); - Square s; + Value result = VALUE_ZERO; for (PieceType pt = KNIGHT; pt <= QUEEN; pt++) - { - Bitboard b = pieces_of_color_and_type(c, pt); - while(b) - { - s = pop_1st_bit(&b); - assert(piece_on(s) == piece_of_color_and_type(c, pt)); - result += piece_value_midgame(pt); - } - } - return result; -} - - -/// Position::is_mate() returns true or false depending on whether the -/// side to move is checkmated. Note that this function is currently very -/// slow, and shouldn't be used frequently inside the search. + result += piece_count(c, pt) * PieceValueMidgame[pt]; -bool Position::is_mate() const { - - if (is_check()) - { - MovePicker mp = MovePicker(*this, false, MOVE_NONE, EmptySearchStack, Depth(0)); - return mp.get_next_move() == MOVE_NONE; - } - return false; + return result; } @@ -1868,122 +1664,70 @@ bool Position::is_mate() const { bool Position::is_draw() const { // Draw by material? - if ( !pawns() + if ( !pieces(PAWN) && (non_pawn_material(WHITE) + non_pawn_material(BLACK) <= BishopValueMidgame)) return true; // Draw by the 50 moves rule? - if (st->rule50 > 100 || (st->rule50 == 100 && !is_check())) + if (st->rule50 > 99 && !is_mate()) return true; // Draw by repetition? - for (int i = 2; i < Min(gamePly, st->rule50); i += 2) - if (history[gamePly - i] == st->key) + for (int i = 4, e = Min(Min(st->gamePly, st->rule50), st->pliesFromNull); i <= e; i += 2) + if (history[st->gamePly - i] == st->key) return true; return false; } -/// Position::has_mate_threat() tests whether a given color has a mate in one -/// from the current position. This function is quite slow, but it doesn't -/// matter, because it is currently only called from PV nodes, which are rare. - -bool Position::has_mate_threat(Color c) { - - StateInfo st1, st2; - Color stm = side_to_move(); - - // The following lines are useless and silly, but prevents gcc from - // emitting a stupid warning stating that u1.lastMove and u1.epSquare might - // be used uninitialized. - st1.lastMove = st->lastMove; - st1.epSquare = st->epSquare; - - if (is_check()) - return false; - - // If the input color is not equal to the side to move, do a null move - if (c != stm) - do_null_move(st1); - - MoveStack mlist[120]; - int count; - bool result = false; - - // Generate legal moves - count = generate_legal_moves(*this, mlist); - - // Loop through the moves, and see if one of them is mate - for (int i = 0; i < count; i++) - { - do_move(mlist[i].move, st2); - if (is_mate()) - result = true; - - undo_move(mlist[i].move); - } +/// Position::is_mate() returns true or false depending on whether the +/// side to move is checkmated. - // Undo null move, if necessary - if (c != stm) - undo_null_move(); +bool Position::is_mate() const { - return result; + MoveStack moves[MOVES_MAX]; + return is_check() && generate(*this, moves) == moves; } -/// Position::init_zobrist() is a static member function which initializes the -/// various arrays used to compute hash keys. +/// Position::init_zobrist() is a static member function which initializes at +/// startup the various arrays used to compute hash keys. void Position::init_zobrist() { - for (int i = 0; i < 2; i++) - for (int j = 0; j < 8; j++) - for (int k = 0; k < 64; k++) - zobrist[i][j][k] = Key(genrand_int64()); - - for (int i = 0; i < 64; i++) - zobEp[i] = Key(genrand_int64()); + int i,j, k; + RKISS rk; - for (int i = 0; i < 16; i++) - zobCastle[i] = genrand_int64(); + for (i = 0; i < 2; i++) for (j = 0; j < 8; j++) for (k = 0; k < 64; k++) + zobrist[i][j][k] = rk.rand(); - zobSideToMove = genrand_int64(); + for (i = 0; i < 64; i++) + zobEp[i] = rk.rand(); - for (int i = 0; i < 2; i++) - for (int j = 0; j < 8; j++) - for (int k = 0; k < 16; k++) - zobMaterial[i][j][k] = (k > 0)? Key(genrand_int64()) : Key(0LL); + for (i = 0; i < 16; i++) + zobCastle[i] = rk.rand(); - for (int i = 0; i < 16; i++) - zobMaterial[0][KING][i] = zobMaterial[1][KING][i] = Key(0ULL); + zobSideToMove = rk.rand(); + zobExclusion = rk.rand(); } /// Position::init_piece_square_tables() initializes the piece square tables. -/// This is a two-step operation: First, the white halves of the tables are -/// copied from the MgPST[][] and EgPST[][] arrays, with a small random number -/// added to each entry if the "Randomness" UCI parameter is non-zero. -/// Second, the black halves of the tables are initialized by mirroring -/// and changing the sign of the corresponding white scores. +/// This is a two-step operation: First, the white halves of the tables are +/// copied from the MgPST[][] and EgPST[][] arrays. Second, the black halves +/// of the tables are initialized by mirroring and changing the sign of the +/// corresponding white scores. void Position::init_piece_square_tables() { - int r = get_option_value_int("Randomness"), i; for (Square s = SQ_A1; s <= SQ_H8; s++) for (Piece p = WP; p <= WK; p++) - { - i = (r == 0)? 0 : (genrand_int32() % (r*2) - r); - MgPieceSquareTable[p][s] = Value(MgPST[p][s] + i); - EgPieceSquareTable[p][s] = Value(EgPST[p][s] + i); - } + PieceSquareTable[p][s] = make_score(MgPST[p][s], EgPST[p][s]); for (Square s = SQ_A1; s <= SQ_H8; s++) for (Piece p = BP; p <= BK; p++) - { - MgPieceSquareTable[p][s] = -MgPieceSquareTable[p-8][flip_square(s)]; - EgPieceSquareTable[p][s] = -EgPieceSquareTable[p-8][flip_square(s)]; - } + PieceSquareTable[p][s] = -PieceSquareTable[p-8][flip_square(s)]; } @@ -1991,33 +1735,31 @@ void Position::init_piece_square_tables() { /// the white and black sides reversed. This is only useful for debugging, /// especially for finding evaluation symmetry bugs. -void Position::flipped_copy(const Position &pos) { +void Position::flipped_copy(const Position& pos) { assert(pos.is_ok()); clear(); + threadID = pos.thread(); // Board for (Square s = SQ_A1; s <= SQ_H8; s++) if (!pos.square_is_empty(s)) - put_piece(Piece(int(pos.piece_on(s)) ^ 8), flip_square(s)); + put_piece(Piece(pos.piece_on(s) ^ 8), flip_square(s)); // Side to move sideToMove = opposite_color(pos.side_to_move()); // Castling rights - if (pos.can_castle_kingside(WHITE)) allow_oo(BLACK); - if (pos.can_castle_queenside(WHITE)) allow_ooo(BLACK); - if (pos.can_castle_kingside(BLACK)) allow_oo(WHITE); - if (pos.can_castle_queenside(BLACK)) allow_ooo(WHITE); + if (pos.can_castle_kingside(WHITE)) do_allow_oo(BLACK); + if (pos.can_castle_queenside(WHITE)) do_allow_ooo(BLACK); + if (pos.can_castle_kingside(BLACK)) do_allow_oo(WHITE); + if (pos.can_castle_queenside(BLACK)) do_allow_ooo(WHITE); initialKFile = pos.initialKFile; initialKRFile = pos.initialKRFile; initialQRFile = pos.initialQRFile; - for (Square sq = SQ_A1; sq <= SQ_H8; sq++) - castleRightsMask[sq] = ALL_CASTLES; - castleRightsMask[make_square(initialKFile, RANK_1)] ^= (WHITE_OO | WHITE_OOO); castleRightsMask[make_square(initialKFile, RANK_8)] ^= (BLACK_OO | BLACK_OOO); castleRightsMask[make_square(initialKRFile, RANK_1)] ^= WHITE_OO; @@ -2038,12 +1780,11 @@ void Position::flipped_copy(const Position &pos) { st->materialKey = compute_material_key(); // Incremental scores - st->mgValue = compute_value(); - st->egValue = compute_value(); + st->value = compute_value(); // Material - npMaterial[WHITE] = compute_non_pawn_material(WHITE); - npMaterial[BLACK] = compute_non_pawn_material(BLACK); + st->npMaterial[WHITE] = compute_non_pawn_material(WHITE); + st->npMaterial[BLACK] = compute_non_pawn_material(BLACK); assert(is_ok()); } @@ -2055,17 +1796,20 @@ void Position::flipped_copy(const Position &pos) { bool Position::is_ok(int* failedStep) const { // What features of the position should be verified? - static const bool debugBitboards = false; - static const bool debugKingCount = false; - static const bool debugKingCapture = false; - static const bool debugCheckerCount = false; - static const bool debugKey = false; - static const bool debugMaterialKey = false; - static const bool debugPawnKey = false; - static const bool debugIncrementalEval = false; - static const bool debugNonPawnMaterial = false; - static const bool debugPieceCounts = false; - static const bool debugPieceList = false; + const bool debugAll = false; + + const bool debugBitboards = debugAll || false; + const bool debugKingCount = debugAll || false; + const bool debugKingCapture = debugAll || false; + const bool debugCheckerCount = debugAll || false; + const bool debugKey = debugAll || false; + const bool debugMaterialKey = debugAll || false; + const bool debugPawnKey = debugAll || false; + const bool debugIncrementalEval = debugAll || false; + const bool debugNonPawnMaterial = debugAll || false; + const bool debugPieceCounts = debugAll || false; + const bool debugPieceList = debugAll || false; + const bool debugCastleSquares = debugAll || false; if (failedStep) *failedStep = 1; @@ -2110,13 +1854,13 @@ bool Position::is_ok(int* failedStep) const { Color us = side_to_move(); Color them = opposite_color(us); Square ksq = king_square(them); - if (square_is_attacked(ksq, us)) + if (attackers_to(ksq) & pieces_of_color(us)) return false; } // Is there more than 2 checkers? if (failedStep) (*failedStep)++; - if (debugCheckerCount && count_1s(st->checkersBB) > 2) + if (debugCheckerCount && count_1s(st->checkersBB) > 2) return false; // Bitboards OK? @@ -2135,7 +1879,7 @@ bool Position::is_ok(int* failedStep) const { // Separate piece type bitboards must have empty intersections for (PieceType p1 = PAWN; p1 <= KING; p1++) for (PieceType p2 = PAWN; p2 <= KING; p2++) - if (p1 != p2 && (pieces_of_type(p1) & pieces_of_type(p2))) + if (p1 != p2 && (pieces(p1) & pieces(p2))) return false; } @@ -2166,23 +1910,17 @@ bool Position::is_ok(int* failedStep) const { // Incremental eval OK? if (failedStep) (*failedStep)++; - if (debugIncrementalEval) - { - if (st->mgValue != compute_value()) - return false; - - if (st->egValue != compute_value()) - return false; - } + if (debugIncrementalEval && st->value != compute_value()) + return false; // Non-pawn material OK? if (failedStep) (*failedStep)++; if (debugNonPawnMaterial) { - if (npMaterial[WHITE] != compute_non_pawn_material(WHITE)) + if (st->npMaterial[WHITE] != compute_non_pawn_material(WHITE)) return false; - if (npMaterial[BLACK] != compute_non_pawn_material(BLACK)) + if (st->npMaterial[BLACK] != compute_non_pawn_material(BLACK)) return false; } @@ -2191,23 +1929,43 @@ bool Position::is_ok(int* failedStep) const { if (debugPieceCounts) for (Color c = WHITE; c <= BLACK; c++) for (PieceType pt = PAWN; pt <= KING; pt++) - if (pieceCount[c][pt] != count_1s(pieces_of_color_and_type(c, pt))) + if (pieceCount[c][pt] != count_1s(pieces(pt, c))) return false; if (failedStep) (*failedStep)++; if (debugPieceList) - { - for(Color c = WHITE; c <= BLACK; c++) - for(PieceType pt = PAWN; pt <= KING; pt++) - for(int i = 0; i < pieceCount[c][pt]; i++) + for (Color c = WHITE; c <= BLACK; c++) + for (PieceType pt = PAWN; pt <= KING; pt++) + for (int i = 0; i < pieceCount[c][pt]; i++) { - if (piece_on(piece_list(c, pt, i)) != piece_of_color_and_type(c, pt)) + if (piece_on(piece_list(c, pt, i)) != make_piece(c, pt)) return false; if (index[piece_list(c, pt, i)] != i) return false; } + + if (failedStep) (*failedStep)++; + if (debugCastleSquares) + { + for (Color c = WHITE; c <= BLACK; c++) + { + if (can_castle_kingside(c) && piece_on(initial_kr_square(c)) != make_piece(c, ROOK)) + return false; + + if (can_castle_queenside(c) && piece_on(initial_qr_square(c)) != make_piece(c, ROOK)) + return false; + } + if (castleRightsMask[initial_kr_square(WHITE)] != (ALL_CASTLES ^ WHITE_OO)) + return false; + if (castleRightsMask[initial_qr_square(WHITE)] != (ALL_CASTLES ^ WHITE_OOO)) + return false; + if (castleRightsMask[initial_kr_square(BLACK)] != (ALL_CASTLES ^ BLACK_OO)) + return false; + if (castleRightsMask[initial_qr_square(BLACK)] != (ALL_CASTLES ^ BLACK_OOO)) + return false; } + if (failedStep) *failedStep = 0; return true; }