X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=87067ea56f644187cf52bf4c4adce75900da9d78;hp=ccc66d5ba79c6779177ad5d6ec672a7d318be5a1;hb=3184852bdce27e387852f4e250c3c5b502706cb3;hpb=fbb53524efd94c4b227c72c725c628a4aa5f9f72 diff --git a/src/position.cpp b/src/position.cpp index ccc66d5b..87067ea5 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) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -19,15 +19,15 @@ #include #include -#include +#include // For std::memset, std::memcmp #include #include #include "bitcount.h" +#include "misc.h" #include "movegen.h" #include "position.h" #include "psqtab.h" -#include "rkiss.h" #include "thread.h" #include "tt.h" #include "uci.h" @@ -47,7 +47,7 @@ namespace Zobrist { Key exclusion; } -Key Position::exclusion_key() const { return st->key ^ Zobrist::exclusion;} +Key Position::exclusion_key() const { return st->key ^ Zobrist::exclusion; } namespace { @@ -123,7 +123,7 @@ std::ostream& operator<<(std::ostream& os, const Position& pos) { << std::setfill('0') << std::setw(16) << pos.st->key << std::dec << "\nCheckers: "; for (Bitboard b = pos.checkers(); b; ) - os << UCI::format_square(pop_lsb(&b)) << " "; + os << UCI::square(pop_lsb(&b)) << " "; return os; } @@ -137,15 +137,15 @@ std::ostream& operator<<(std::ostream& os, const Position& pos) { void Position::init() { - RKISS rk; + PRNG rng(1070372); for (Color c = WHITE; c <= BLACK; ++c) for (PieceType pt = PAWN; pt <= KING; ++pt) for (Square s = SQ_A1; s <= SQ_H8; ++s) - Zobrist::psq[c][pt][s] = rk.rand(); + Zobrist::psq[c][pt][s] = rng.rand(); for (File f = FILE_A; f <= FILE_H; ++f) - Zobrist::enpassant[f] = rk.rand(); + Zobrist::enpassant[f] = rng.rand(); for (int cr = NO_CASTLING; cr <= ANY_CASTLING; ++cr) { @@ -153,12 +153,12 @@ void Position::init() { while (b) { Key k = Zobrist::castling[1ULL << pop_lsb(&b)]; - Zobrist::castling[cr] ^= k ? k : rk.rand(); + Zobrist::castling[cr] ^= k ? k : rng.rand(); } } - Zobrist::side = rk.rand(); - Zobrist::exclusion = rk.rand(); + Zobrist::side = rng.rand(); + Zobrist::exclusion = rng.rand(); for (PieceType pt = PAWN; pt <= KING; ++pt) { @@ -176,9 +176,8 @@ void Position::init() { } -/// Position::operator=() creates a copy of 'pos'. We want the new born Position -/// object to not depend on any external data so we detach state pointer from -/// the source one. +/// Position::operator=() creates a copy of 'pos' but detaching the state pointer +/// from the source to be self-consistent and not depending on any external data. Position& Position::operator=(const Position& pos) { @@ -382,7 +381,7 @@ void Position::set_state(StateInfo* si) const { if (sideToMove == BLACK) si->key ^= Zobrist::side; - si->key ^= Zobrist::castling[st->castlingRights]; + si->key ^= Zobrist::castling[si->castlingRights]; for (Bitboard b = pieces(PAWN); b; ) { @@ -444,7 +443,7 @@ const string Position::fen() const { if (!can_castle(WHITE) && !can_castle(BLACK)) ss << '-'; - ss << (ep_square() == SQ_NONE ? " - " : " " + UCI::format_square(ep_square()) + " ") + ss << (ep_square() == SQ_NONE ? " - " : " " + UCI::square(ep_square()) + " ") << st->rule50 << " " << 1 + (gamePly - (sideToMove == BLACK)) / 2; return ss.str(); @@ -642,7 +641,7 @@ bool Position::gives_check(Move m, const CheckInfo& ci) const { return true; // Is there a discovered check? - if ( unlikely(ci.dcCandidates) + if ( ci.dcCandidates && (ci.dcCandidates & from) && !aligned(from, to, ci.ksq)) return true; @@ -694,25 +693,21 @@ void Position::do_move(Move m, StateInfo& newSt) { do_move(m, newSt, ci, gives_check(m, ci)); } -void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveIsCheck) { +void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool givesCheck) { assert(is_ok(m)); assert(&newSt != st); ++nodes; - Key k = st->key; + Key k = st->key ^ Zobrist::side; // Copy some fields of the old state to our new StateInfo object except the // ones which are going to be recalculated from scratch anyway and then switch // our state pointer to point to the new (ready to be updated) state. - std::memcpy(&newSt, st, StateCopySize64 * sizeof(uint64_t)); - + std::memcpy(&newSt, st, offsetof(StateInfo, key)); newSt.previous = st; st = &newSt; - // Update side to move - k ^= Zobrist::side; - // Increment ply counters. In particular, rule50 will be reset to zero later on // in case of a capture or a pawn move. ++gamePly; @@ -723,17 +718,16 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI Color them = ~us; Square from = from_sq(m); Square to = to_sq(m); - Piece pc = piece_on(from); - PieceType pt = type_of(pc); + PieceType pt = type_of(piece_on(from)); PieceType captured = type_of(m) == ENPASSANT ? PAWN : type_of(piece_on(to)); - assert(color_of(pc) == us); - assert(piece_on(to) == NO_PIECE || color_of(piece_on(to)) == them || type_of(m) == CASTLING); + assert(color_of(piece_on(from)) == us); + assert(piece_on(to) == NO_PIECE || color_of(piece_on(to)) == (type_of(m) != CASTLING ? them : us)); assert(captured != KING); if (type_of(m) == CASTLING) { - assert(pc == make_piece(us, KING)); + assert(pt == KING); Square rfrom, rto; do_castling(from, to, rfrom, rto); @@ -753,7 +747,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI { if (type_of(m) == ENPASSANT) { - capsq += pawn_push(them); + capsq -= pawn_push(us); assert(pt == PAWN); assert(to == st->epSquare); @@ -761,7 +755,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI assert(piece_on(to) == NO_PIECE); assert(piece_on(capsq) == make_piece(them, PAWN)); - board[capsq] = NO_PIECE; + board[capsq] = NO_PIECE; // Not done by remove_piece() } st->pawnKey ^= Zobrist::psq[them][PAWN][capsq]; @@ -775,7 +769,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI // Update material hash key and prefetch access to materialTable k ^= Zobrist::psq[them][captured][capsq]; st->materialKey ^= Zobrist::psq[them][captured][pieceCount[them][captured]]; - prefetch((char*)thisThread->materialTable[st->materialKey]); + prefetch(thisThread->materialTable[st->materialKey]); // Update incremental scores st->psq -= psq[them][captured][capsq]; @@ -811,9 +805,9 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI { // Set en-passant square if the moved pawn can be captured if ( (int(to) ^ int(from)) == 16 - && (attacks_from(from + pawn_push(us), us) & pieces(them, PAWN))) + && (attacks_from(to - pawn_push(us), us) & pieces(them, PAWN))) { - st->epSquare = Square((from + to) / 2); + st->epSquare = (from + to) / 2; k ^= Zobrist::enpassant[file_of(st->epSquare)]; } @@ -842,7 +836,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI // Update pawn hash key and prefetch access to pawnsTable st->pawnKey ^= Zobrist::psq[us][PAWN][from] ^ Zobrist::psq[us][PAWN][to]; - prefetch((char*)thisThread->pawnsTable[st->pawnKey]); + prefetch(thisThread->pawnsTable[st->pawnKey]); // Reset rule 50 draw counter st->rule50 = 0; @@ -860,7 +854,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI // Update checkers bitboard: piece must be already moved due to attacks_from() st->checkersBB = 0; - if (moveIsCheck) + if (givesCheck) { if (type_of(m) != NORMAL) st->checkersBB = attackers_to(king_square(them)) & pieces(us); @@ -871,8 +865,10 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI st->checkersBB |= to; // Discovered checks - if (unlikely(ci.dcCandidates) && (ci.dcCandidates & from)) + if (ci.dcCandidates && (ci.dcCandidates & from)) { + assert(pt != QUEEN); + if (pt != ROOK) st->checkersBB |= attacks_from(king_square(them)) & pieces(us, QUEEN, ROOK); @@ -907,11 +903,11 @@ void Position::undo_move(Move m) { if (type_of(m) == PROMOTION) { - assert(pt == promotion_type(m)); assert(relative_rank(us, to) == RANK_8); - assert(promotion_type(m) >= KNIGHT && promotion_type(m) <= QUEEN); + assert(pt == promotion_type(m)); + assert(pt >= KNIGHT && pt <= QUEEN); - remove_piece(to, us, promotion_type(m)); + remove_piece(to, us, pt); put_piece(to, us, PAWN); pt = PAWN; } @@ -937,6 +933,7 @@ void Position::undo_move(Move m) { assert(to == st->previous->epSquare); assert(relative_rank(us, to) == RANK_6); assert(piece_on(capsq) == NO_PIECE); + assert(st->capturedType == PAWN); } put_piece(capsq, ~us, st->capturedType); // Restore the captured piece @@ -976,9 +973,9 @@ void Position::do_castling(Square from, Square& to, Square& rfrom, Square& rto) void Position::do_null_move(StateInfo& newSt) { assert(!checkers()); + assert(&newSt != st); - std::memcpy(&newSt, st, sizeof(StateInfo)); // Fully copy here - + std::memcpy(&newSt, st, sizeof(StateInfo)); newSt.previous = st; st = &newSt; @@ -989,7 +986,7 @@ void Position::do_null_move(StateInfo& newSt) { } st->key ^= Zobrist::side; - prefetch((char*)TT.first_entry(st->key)); + prefetch(TT.first_entry(st->key)); ++st->rule50; st->pliesFromNull = 0; @@ -1061,8 +1058,8 @@ Value Position::see(Move m) const { stm = color_of(piece_on(from)); occupied = pieces() ^ from; - // Castling moves are implemented as king capturing the rook so cannot be - // handled correctly. Simply return 0 that is always the correct value + // Castling moves are implemented as king capturing the rook so cannot + // be handled correctly. Simply return VALUE_ZERO that is always correct // unless in the rare case the rook ends up under attack. if (type_of(m) == CASTLING) return VALUE_ZERO; @@ -1099,21 +1096,11 @@ Value Position::see(Move m) const { // Locate and remove the next least valuable attacker captured = min_attacker(byTypeBB, to, stmAttackers, occupied, attackers); - - // Stop before processing a king capture - if (captured == KING) - { - if (stmAttackers == attackers) - ++slIndex; - - break; - } - stm = ~stm; stmAttackers = attackers & pieces(stm); ++slIndex; - } while (stmAttackers); + } while (stmAttackers && (captured != KING || (--slIndex, false))); // Stop before a king capture // 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. @@ -1148,10 +1135,6 @@ bool Position::is_draw() const { /// Position::flip() flips position with the white and black sides reversed. This /// is only useful for debugging e.g. for finding evaluation symmetry bugs. -static char toggle_case(char c) { - return char(islower(c) ? toupper(c) : tolower(c)); -} - void Position::flip() { string f, token; @@ -1169,7 +1152,8 @@ void Position::flip() { ss >> token; // Castling availability f += token + " "; - std::transform(f.begin(), f.end(), f.begin(), toggle_case); + std::transform(f.begin(), f.end(), f.begin(), + [](char c) { return char(islower(c) ? toupper(c) : tolower(c)); }); ss >> token; // En passant square f += (token == "-" ? token : token.replace(1, 1, token[1] == '3' ? "6" : "3")); @@ -1186,96 +1170,77 @@ void Position::flip() { /// Position::pos_is_ok() performs some consistency checks for the position object. /// This is meant to be helpful when debugging. -bool Position::pos_is_ok(int* step) const { +bool Position::pos_is_ok(int* failedStep) const { - // Which parts of the position should be verified? - const bool all = false; + const bool Fast = true; // Quick (default) or full check? - const bool testBitboards = all || false; - const bool testState = all || false; - const bool testKingCount = all || false; - const bool testKingCapture = all || false; - const bool testPieceCounts = all || false; - const bool testPieceList = all || false; - const bool testCastlingSquares = all || false; + enum { Default, King, Bitboards, State, Lists, Castling }; - if (step) - *step = 1; - - if ( (sideToMove != WHITE && sideToMove != BLACK) - || piece_on(king_square(WHITE)) != W_KING - || piece_on(king_square(BLACK)) != B_KING - || ( ep_square() != SQ_NONE - && relative_rank(sideToMove, ep_square()) != RANK_6)) - return false; - - if (step && ++*step, testBitboards) + for (int step = Default; step <= (Fast ? Default : Castling); step++) { - // The intersection of the white and black pieces must be empty - if (pieces(WHITE) & pieces(BLACK)) - return false; - - // The union of the white and black pieces must be equal to all - // occupied squares - if ((pieces(WHITE) | pieces(BLACK)) != pieces()) - return false; + if (failedStep) + *failedStep = step; + + if (step == Default) + if ( (sideToMove != WHITE && sideToMove != BLACK) + || piece_on(king_square(WHITE)) != W_KING + || piece_on(king_square(BLACK)) != B_KING + || ( ep_square() != SQ_NONE + && relative_rank(sideToMove, ep_square()) != RANK_6)) + return false; - // 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(p1) & pieces(p2))) - return false; - } + if (step == King) + if ( std::count(board, board + SQUARE_NB, W_KING) != 1 + || std::count(board, board + SQUARE_NB, B_KING) != 1 + || attackers_to(king_square(~sideToMove)) & pieces(sideToMove)) + return false; - if (step && ++*step, testState) - { - StateInfo si; - set_state(&si); - if ( st->key != si.key - || st->pawnKey != si.pawnKey - || st->materialKey != si.materialKey - || st->nonPawnMaterial[WHITE] != si.nonPawnMaterial[WHITE] - || st->nonPawnMaterial[BLACK] != si.nonPawnMaterial[BLACK] - || st->psq != si.psq - || st->checkersBB != si.checkersBB) - return false; - } + if (step == Bitboards) + { + if ( (pieces(WHITE) & pieces(BLACK)) + ||(pieces(WHITE) | pieces(BLACK)) != pieces()) + return false; - if (step && ++*step, testKingCount) - if ( std::count(board, board + SQUARE_NB, W_KING) != 1 - || std::count(board, board + SQUARE_NB, B_KING) != 1) - return false; + for (PieceType p1 = PAWN; p1 <= KING; ++p1) + for (PieceType p2 = PAWN; p2 <= KING; ++p2) + if (p1 != p2 && (pieces(p1) & pieces(p2))) + return false; + } - if (step && ++*step, testKingCapture) - if (attackers_to(king_square(~sideToMove)) & pieces(sideToMove)) - return false; + if (step == State) + { + StateInfo si = *st; + set_state(&si); + if (std::memcmp(&si, st, sizeof(StateInfo))) + return false; + } - if (step && ++*step, testPieceCounts) - for (Color c = WHITE; c <= BLACK; ++c) - for (PieceType pt = PAWN; pt <= KING; ++pt) - if (pieceCount[c][pt] != popcount(pieces(c, pt))) - return false; - - if (step && ++*step, testPieceList) - for (Color c = WHITE; c <= BLACK; ++c) - for (PieceType pt = PAWN; pt <= KING; ++pt) - for (int i = 0; i < pieceCount[c][pt]; ++i) - if ( board[pieceList[c][pt][i]] != make_piece(c, pt) - || index[pieceList[c][pt][i]] != i) + if (step == Lists) + for (Color c = WHITE; c <= BLACK; ++c) + for (PieceType pt = PAWN; pt <= KING; ++pt) + { + if (pieceCount[c][pt] != popcount(pieces(c, pt))) return false; - if (step && ++*step, testCastlingSquares) - for (Color c = WHITE; c <= BLACK; ++c) - for (CastlingSide s = KING_SIDE; s <= QUEEN_SIDE; s = CastlingSide(s + 1)) - { - if (!can_castle(c | s)) - continue; - - if ( (castlingRightsMask[king_square(c)] & (c | s)) != (c | s) - || piece_on(castlingRookSquare[c | s]) != make_piece(c, ROOK) - || castlingRightsMask[castlingRookSquare[c | s]] != (c | s)) - return false; - } + for (int i = 0; i < pieceCount[c][pt]; ++i) + if ( board[pieceList[c][pt][i]] != make_piece(c, pt) + || index[pieceList[c][pt][i]] != i) + return false; + } + + if (step == Castling) + for (Color c = WHITE; c <= BLACK; ++c) + for (CastlingSide s = KING_SIDE; s <= QUEEN_SIDE; s = CastlingSide(s + 1)) + { + if (!can_castle(c | s)) + continue; + + if ( piece_on(castlingRookSquare[c | s]) != make_piece(c, ROOK) + || castlingRightsMask[castlingRookSquare[c | s]] != (c | s) + ||(castlingRightsMask[king_square(c)] & (c | s)) != (c | s)) + return false; + } + } return true; }