along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-
-////
-//// Includes
-////
-
-#include <algorithm>
#include <cassert>
#include <cstring>
#include <fstream>
-#include <map>
#include <iostream>
#include <sstream>
#include "bitcount.h"
#include "movegen.h"
-#include "movepick.h"
#include "position.h"
#include "psqtab.h"
#include "rkiss.h"
-#include "san.h"
+#include "thread.h"
#include "tt.h"
#include "ucioption.h"
using std::cout;
using std::endl;
-
-////
-//// Position's static data definitions
-////
-
Key Position::zobrist[2][8][64];
Key Position::zobEp[64];
Key Position::zobCastle[16];
Score Position::PieceSquareTable[16][64];
// Material values arrays, indexed by Piece
-const Value Position::PieceValueMidgame[17] = {
+const Value PieceValueMidgame[17] = {
VALUE_ZERO,
PawnValueMidgame, KnightValueMidgame, BishopValueMidgame,
RookValueMidgame, QueenValueMidgame, VALUE_ZERO,
RookValueMidgame, QueenValueMidgame
};
-const Value Position::PieceValueEndgame[17] = {
+const Value PieceValueEndgame[17] = {
VALUE_ZERO,
PawnValueEndgame, KnightValueEndgame, BishopValueEndgame,
RookValueEndgame, QueenValueEndgame, VALUE_ZERO,
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);
- bool isZero(char c) { return c == '0'; }
-
- struct PieceLetters : public std::map<char, Piece> {
-
- 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;
- }
-
- char from_piece(Piece p) const {
-
- std::map<char, Piece>::const_iterator it;
- for (it = begin(); it != end(); ++it)
- if (it->second == p)
- return it->first;
-
- assert(false);
- return 0;
- }
- };
-
- PieceLetters pieceLetters;
+ // To convert a Piece to and from a FEN char
+ const string PieceToChar(".PNBRQK pnbrqk ");
}
Color us = pos.side_to_move();
Color them = opposite_color(us);
+ Square ksq = pos.king_square(them);
- ksq = pos.king_square(them);
dcCandidates = pos.discovered_check_candidates(us);
+ pinned = pos.pinned_pieces(us);
- checkSq[PAWN] = pos.attacks_from<PAWN>(ksq, them);
+ checkSq[PAWN]
= pos.attacks_from<PAWN>(ksq, them);
checkSq[KNIGHT] = pos.attacks_from<KNIGHT>(ksq);
checkSq[BISHOP] = pos.attacks_from<BISHOP>(ksq);
- checkSq[ROOK] = pos.attacks_from<ROOK>(ksq);
- checkSq[QUEEN] = checkSq[BISHOP] | checkSq[ROOK];
- checkSq[KING] = EmptyBoardBB;
+ checkSq[ROOK] = pos.attacks_from<ROOK>(ksq);
+ checkSq[QUEEN] = checkSq[BISHOP] | checkSq[ROOK];
+ checkSq[KING] = EmptyBoardBB;
}
nodes = 0;
}
-Position::Position(const string& fen, int th) {
+Position::Position(const string& fen, bool isChess960, int th) {
- from_fen(fen);
+ from_fen(fen, isChess960);
threadID = th;
}
/// 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 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.
+ 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
*/
char token;
+ int hmc, fmn;
+ size_t p;
+ Square sq = SQ_A8;
std::istringstream ss(fen);
- Rank rank = RANK_8;
- File file = FILE_A;
clear();
+ ss >> std::noskipws;
// 1. Piece placement field
- while (ss.get(token) && token != ' ')
+ while ((ss >> token) && !isspace(token))
{
- if (isdigit(token))
+ if ((p = PieceToChar.find(token)) != string::npos)
{
- file += File(token - '0'); // Skip the given number of files
- continue;
+ put_piece(Piece(p), sq);
+ sq++;
}
+ else if (isdigit(token))
+ sq += Square(token - '0'); // Skip the given number of files
else if (token == '/')
- {
- file = FILE_A;
- rank--;
- continue;
- }
-
- if (pieceLetters.find(token) == pieceLetters.end())
+ sq -= SQ_A3; // Jump back of 2 rows
+ else
goto incorrect_fen;
-
- put_piece(pieceLetters[token], make_square(file, rank));
- file++;
}
// 2. Active color
- if (!ss.get(token) || (token != 'w' && token != 'b'))
+ if (!(ss >> token) || (token != 'w' && token != 'b'))
goto incorrect_fen;
sideToMove = (token == 'w' ? WHITE : BLACK);
- if (!ss.get(token) || token != ' ')
+ if (!(ss >> token) || !isspace(token))
goto incorrect_fen;
// 3. Castling availability
- while (ss.get(token) && token != ' ')
- {
- if (token == '-')
- continue;
-
+ while ((ss >> token) && !isspace(token))
if (!set_castling_rights(token))
goto incorrect_fen;
- }
- // 4. En passant square -- ignore if no capture is possible
+ // 4. En passant square
char col, row;
- if ( (ss.get(col) && (col >= 'a' && col <= 'h'))
- && (ss.get(row) && (row == '3' || row == '6')))
+ if ( ((ss >> col) && (col >= 'a' && col <= 'h'))
+ && ((ss >> row) && (row == '3' || row == '6')))
{
- Square fenEpSquare = make_square(file_from_char(col), rank_from_char(row));
- Color them = opposite_color(sideToMove);
+ st->epSquare = make_square(File(col - 'a') + FILE_A, Rank(row - '1') + RANK_1);
- if (attacks_from<PAWN>(fenEpSquare, them) & pieces(PAWN, sideToMove))
- st->epSquare = fenEpSquare;
+ // Ignore if no capture is possible
+ Color them = opposite_color(sideToMove);
+ if (!(attacks_from<PAWN>(st->epSquare, them) & pieces(PAWN, sideToMove)))
+ st->epSquare = SQ_NONE;
}
- // 5-6. Halfmove clock and fullmove number are not parsed
+ // 5. Halfmove clock
+ if (ss >> std::skipws >> hmc)
+ st->rule50 = hmc;
+
+ // 6. Fullmove number
+ if (ss >> fmn)
+ startPosPlyCounter = (fmn - 1) * 2 + int(sideToMove == BLACK);
// Various initialisations
castleRightsMask[make_square(initialKFile, RANK_1)] ^= WHITE_OO | WHITE_OOO;
castleRightsMask[make_square(initialQRFile, RANK_1)] ^= WHITE_OOO;
castleRightsMask[make_square(initialQRFile, RANK_8)] ^= BLACK_OOO;
- isChess960 = initialKFile != FILE_E
- || initialQRFile != FILE_A
- || initialKRFile != FILE_H;
-
+ chess960 = isChess960;
find_checkers();
st->key = compute_key();
for (Square sq = sqH; sq >= sqA; sq--)
if (piece_on(sq) == rook)
{
- do_allow_oo(c);
+ set_castle_kingside(c);
initialKRFile = square_file(sq);
break;
}
for (Square sq = sqA; sq <= sqH; sq++)
if (piece_on(sq) == rook)
{
- do_allow_ooo(c);
+ set_castle_queenside(c);
initialQRFile = square_file(sq);
break;
}
File rookFile = File(token - 'A') + FILE_A;
if (rookFile < initialKFile)
{
- do_allow_ooo(c);
+ set_castle_queenside(c);
initialQRFile = rookFile;
}
else
{
- do_allow_oo(c);
+ set_castle_kingside(c);
initialKRFile = rookFile;
}
}
- else return false;
+ else
+ return token == '-';
return true;
}
string fen;
Square sq;
- char emptyCnt = '0';
+ char emptyCnt;
- for (Rank rank = RANK_8; rank >= RANK_1; rank--)
+ for (Rank rank = RANK_8; rank >= RANK_1; rank--, fen += '/')
{
+ emptyCnt = '0';
+
for (File file = FILE_A; file <= FILE_H; file++)
{
sq = make_square(file, rank);
if (square_is_occupied(sq))
{
- fen += emptyCnt;
- fen += pieceLetters.from_piece(piece_on(sq));
- emptyCnt = '0';
+ if (emptyCnt != '0')
+ {
+ fen += emptyCnt;
+ emptyCnt = '0';
+ }
+ fen += PieceToChar[piece_on(sq)];
} else
emptyCnt++;
}
- fen += emptyCnt;
- fen += '/';
- emptyCnt = '0';
+
+ if (emptyCnt != '0')
+ fen += emptyCnt;
}
- fen.erase(std::remove_if(fen.begin(), fen.end(), isZero), fen.end());
- fen.erase(--fen.end());
fen += (sideToMove == WHITE ? " w " : " b ");
if (st->castleRights != CASTLES_NONE)
{
if (can_castle_kingside(WHITE))
- fen += isChess960 ? char(toupper(file_to_char(initialKRFile))) : 'K';
+ fen += chess960 ? char(toupper(file_to_char(initialKRFile))) : 'K';
if (can_castle_queenside(WHITE))
- fen += isChess960 ? char(toupper(file_to_char(initialQRFile))) : 'Q';
+ fen += chess960 ? char(toupper(file_to_char(initialQRFile))) : 'Q';
if (can_castle_kingside(BLACK))
- fen += isChess960 ? file_to_char(initialKRFile) : 'k';
+ fen += chess960 ? file_to_char(initialKRFile) : 'k';
if (can_castle_queenside(BLACK))
- fen += isChess960 ? file_to_char(initialQRFile) : 'q';
+ fen += chess960 ? file_to_char(initialQRFile) : 'q';
} else
fen += '-';
void Position::print(Move move) const {
const char* dottedLine = "\n+---+---+---+---+---+---+---+---+\n";
- static bool requestPending = false;
-
- // Check for reentrancy, as example when called from inside
- // MovePicker that is used also here in move_to_san()
- if (requestPending)
- return;
-
- requestPending = true;
if (move)
{
for (File file = FILE_A; file <= FILE_H; file++)
{
Square sq = make_square(file, rank);
- char c = (color_of_piece_on(sq) == BLACK ? '=' : ' ');
Piece piece = piece_on(sq);
if (piece == PIECE_NONE && square_color(sq) == DARK)
piece = PIECE_NONE_DARK_SQ;
- cout << c << pieceLetters.from_piece(piece) << c << '|';
+ char c = (color_of_piece_on(sq) == BLACK ? '=' : ' ');
+ cout << c << PieceToChar[piece] << c << '|';
}
}
cout << dottedLine << "Fen is: " << to_fen() << "\nKey is: " << st->key << endl;
- requestPending = false;
}
| (attacks_from<KING>(s) & pieces(KING));
}
+Bitboard Position::attackers_to(Square s, Bitboard occ) const {
+
+ return (attacks_from<PAWN>(s, BLACK) & pieces(PAWN, WHITE))
+ | (attacks_from<PAWN>(s, WHITE) & pieces(PAWN, BLACK))
+ | (attacks_from<KNIGHT>(s) & pieces(KNIGHT))
+ | (rook_attacks_bb(s, occ) & pieces(ROOK, QUEEN))
+ | (bishop_attacks_bb(s, occ) & pieces(BISHOP, QUEEN))
+ | (attacks_from<KING>(s) & pieces(KING));
+}
+
/// Position::attacks_from() computes a bitboard of all attacks
/// of a given piece put in a given square.
case WB: case BB: return attacks_from<BISHOP>(s);
case WR: case BR: return attacks_from<ROOK>(s);
case WQ: case BQ: return attacks_from<QUEEN>(s);
- default: return StepAttackBB[p][s];
+ default: return StepAttacksBB[p][s];
}
}
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 StepAttackBB[p][s];
+ default: return StepAttacksBB[p][s];
}
}
assert(move_is_ok(m));
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();
+ Square from = move_from(m);
+
+ assert(color_of_piece_on(from) == us);
+ assert(piece_on(king_square(us)) == make_piece(us, KING));
// 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(from) == make_piece(us, PAWN));
+ assert(piece_on(capsq) == make_piece(them, PAWN));
assert(piece_on(to) == PIECE_NONE);
clear_bit(&b, from);
&& !(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)) == piece_of_color_and_type(us, KING));
-
// If the moving piece is a king, check whether the destination
- // square is attacked by the opponent.
+ // square is attacked by the opponent. Castling moves are checked
+ // for legality during move generation.
if (type_of_piece_on(from) == KING)
- return !(attackers_to(move_to(m)) & pieces_of_color(opposite_color(us)));
+ return move_is_castle(m) || !(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.
}
-/// Position::pl_move_is_evasion() tests whether a pseudo-legal move is a legal evasion
+/// Position::move_is_pl_slow() takes a position and a move and tests whether
+/// the move is pseudo legal. This version is not very fast and should be used
+/// only in non time-critical paths.
-bool Position::pl_move_is_evasion(Move m, Bitboard pinned) const
-{
- assert(is_check());
+bool Position::move_is_pl_slow(const Move m) const {
- Color us = side_to_move();
+ MoveStack mlist[MAX_MOVES];
+ MoveStack *cur, *last;
+
+ last = in_check() ? generate<MV_EVASION>(*this, mlist)
+ : generate<MV_NON_EVASION>(*this, mlist);
+
+ for (cur = mlist; cur != last; cur++)
+ if (cur->move == m)
+ return true;
+
+ return false;
+}
+
+
+/// Fast version of Position::move_is_pl() that takes a position a move and a
+/// bitboard of pinned pieces as input, and tests whether the move is pseudo legal.
+
+bool Position::move_is_pl(const Move m) const {
+
+ assert(is_ok());
+
+ Color us = sideToMove;
+ Color them = opposite_color(sideToMove);
Square from = move_from(m);
Square to = move_to(m);
+ Piece pc = piece_on(from);
- // 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);
+ // Use a slower but simpler function for uncommon cases
+ if (move_is_special(m))
+ return move_is_pl_slow(m);
- Bitboard target = checkers();
- Square checksq = pop_1st_bit(&target);
+ // Is not a promotion, so promotion piece must be empty
+ if (promotion_piece_type(m) - 2 != PIECE_TYPE_NONE)
+ return false;
- if (target) // double check ?
+ // If the from square is not occupied by a piece belonging to the side to
+ // move, the move is obviously not legal.
+ if (pc == PIECE_NONE || color_of_piece(pc) != us)
return false;
- // 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);
-}
+ // The destination square cannot be occupied by a friendly piece
+ if (color_of_piece_on(to) == us)
+ return false;
+
+ // Handle the special case of a pawn move
+ if (type_of_piece(pc) == PAWN)
+ {
+ // Move direction must be compatible with pawn color
+ int direction = to - from;
+ if ((us == WHITE) != (direction > 0))
+ return false;
+
+ // We have already handled promotion moves, so destination
+ // cannot be on the 8/1th rank.
+ if (square_rank(to) == RANK_8 || square_rank(to) == RANK_1)
+ return false;
+
+ // Proceed according to the square delta between the origin and
+ // destination squares.
+ switch (direction)
+ {
+ case DELTA_NW:
+ case DELTA_NE:
+ case DELTA_SW:
+ case DELTA_SE:
+ // Capture. The destination square must be occupied by an enemy
+ // piece (en passant captures was handled earlier).
+ if (color_of_piece_on(to) != them)
+ return false;
+
+ // From and to files must be one file apart, avoids a7h5
+ if (abs(square_file(from) - square_file(to)) != 1)
+ return false;
+ break;
+
+ case DELTA_N:
+ case DELTA_S:
+ // Pawn push. The destination square must be empty.
+ if (!square_is_empty(to))
+ return false;
+ break;
+
+ case DELTA_NN:
+ // Double white pawn push. The destination square must be on the fourth
+ // rank, and both the destination square and the square between the
+ // source and destination squares must be empty.
+ if ( square_rank(to) != RANK_4
+ || !square_is_empty(to)
+ || !square_is_empty(from + DELTA_N))
+ return false;
+ break;
+
+ case DELTA_SS:
+ // Double black pawn push. The destination square must be on the fifth
+ // rank, and both the destination square and the square between the
+ // source and destination squares must be empty.
+ if ( square_rank(to) != RANK_5
+ || !square_is_empty(to)
+ || !square_is_empty(from + DELTA_S))
+ return false;
+ break;
+ default:
+ return false;
+ }
+ }
+ else if (!bit_is_set(attacks_from(pc, from), to))
+ return false;
+
+ if (in_check())
+ {
+ // In case of king moves under check we have to remove king so to catch
+ // as invalid moves like b1a1 when opposite queen is on c1.
+ if (type_of_piece_on(from) == KING)
+ {
+ Bitboard b = occupied_squares();
+ clear_bit(&b, from);
+ if (attackers_to(move_to(m), b) & pieces_of_color(opposite_color(us)))
+ return false;
+ }
+ else
+ {
+ Bitboard target = checkers();
+ Square checksq = pop_1st_bit(&target);
-/// Position::move_is_check() tests whether a pseudo-legal move is a check
+ if (target) // double check ? In this case a king move is required
+ return false;
-bool Position::move_is_check(Move m) const {
+ // Our move must be a blocking evasion or a capture of the checking piece
+ target = squares_between(checksq, king_square(us)) | checkers();
+ if (!bit_is_set(target, move_to(m)))
+ return false;
+ }
+ }
- return move_is_check(m, CheckInfo(*this));
+ return true;
}
-bool Position::move_is_check(Move m, const CheckInfo& ci) const {
+
+/// Position::move_gives_check() tests whether a pseudo-legal move is a check
+
+bool Position::move_gives_check(Move m, const CheckInfo& ci) const {
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) == piece_of_color_and_type(opposite_color(side_to_move()), KING));
Square from = move_from(m);
Square to = move_to(m);
{
// For pawn and king moves we need to verify also direction
if ( (pt != PAWN && pt != KING)
- || !squares_aligned(from, to, ci.ksq))
+ || !squares_aligned(from, to, king_square(opposite_color(side_to_move()))))
return true;
}
Color us = side_to_move();
Bitboard b = occupied_squares();
+ Square ksq = king_square(opposite_color(us));
// Promotion with check ?
if (move_is_promotion(m))
{
clear_bit(&b, from);
- switch (move_promotion_piece(m))
+ switch (promotion_piece_type(m))
{
case KNIGHT:
- return bit_is_set(attacks_from<KNIGHT>(to), ci.ksq);
+ return bit_is_set(attacks_from<KNIGHT>(to), ksq);
case BISHOP:
- return bit_is_set(bishop_attacks_bb(to, b), ci.ksq);
+ return bit_is_set(bishop_attacks_bb(to, b), ksq);
case ROOK:
- return bit_is_set(rook_attacks_bb(to, b), ci.ksq);
+ return bit_is_set(rook_attacks_bb(to, b), ksq);
case QUEEN:
- return bit_is_set(queen_attacks_bb(to, b), ci.ksq);
+ return bit_is_set(queen_attacks_bb(to, b), ksq);
default:
assert(false);
}
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));
+ return (rook_attacks_bb(ksq, b) & pieces(ROOK, QUEEN, us))
+ ||(bishop_attacks_bb(ksq, b) & pieces(BISHOP, QUEEN, us));
}
// Castling with check ?
clear_bit(&b, rfrom);
set_bit(&b, rto);
set_bit(&b, kto);
- return bit_is_set(rook_attacks_bb(rto, b), ci.ksq);
+ return bit_is_set(rook_attacks_bb(rto, b), ksq);
}
return false;
}
+/// 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.
+
+void Position::do_setup_move(Move m) {
+
+ StateInfo newSt;
+
+ do_move(m, 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;
+
+ // Update the number of plies played from the starting position
+ startPosPlyCounter++;
+
+ // Our StateInfo newSt is about going out of scope so copy
+ // its content 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.
-/// Pseudo-legal moves should be filtered out before this function is called.
+/// to a StateInfo object. The move is assumed to be legal. Pseudo-legal
+/// moves should be filtered out before this function is called.
void Position::do_move(Move m, StateInfo& newSt) {
CheckInfo ci(*this);
- do_move(m, newSt, ci, move_is_check(m, ci));
+ do_move(m, newSt, ci, move_gives_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;
Value npMaterial[2];
};
- if (&newSt != st)
- memcpy(&newSt, st, sizeof(ReducedStateInfo));
+ memcpy(&newSt, st, sizeof(ReducedStateInfo));
newSt.previous = st;
st = &newSt;
assert(color_of_piece_on(from) == us);
assert(color_of_piece_on(to) == them || square_is_empty(to));
- assert(!(ep || pm) || piece == piece_of_color_and_type(us, PAWN));
+ assert(!(ep || pm) || piece == make_piece(us, PAWN));
assert(!pm || relative_rank(us, to) == RANK_8);
if (capture)
st->epSquare = SQ_NONE;
}
- // Update castle rights, try to shortcut a common case
- int cm = castleRightsMask[from] & castleRightsMask[to];
- if (cm != ALL_CASTLES && ((cm & st->castleRights) != st->castleRights))
+ // Update castle rights if needed
+ if ( st->castleRights != CASTLES_NONE
+ && (castleRightsMask[from] & castleRightsMask[to]) != ALL_CASTLES)
{
key ^= zobCastle[st->castleRights];
- st->castleRights &= castleRightsMask[from];
- st->castleRights &= castleRightsMask[to];
+ st->castleRights &= castleRightsMask[from] & castleRightsMask[to];
key ^= zobCastle[st->castleRights];
}
// Update pawn hash key and prefetch in L1/L2 cache
st->pawnKey ^= zobrist[us][PAWN][from] ^ zobrist[us][PAWN][to];
- prefetchPawn(st->pawnKey, threadID);
// Set en passant square, only if moved pawn can be captured
if ((to ^ from) == 16)
if (pm) // promotion ?
{
- PieceType promotion = move_promotion_piece(m);
+ PieceType promotion = promotion_piece_type(m);
assert(promotion >= KNIGHT && promotion <= QUEEN);
// Insert promoted piece instead of pawn
clear_bit(&(byTypeBB[PAWN]), to);
set_bit(&(byTypeBB[promotion]), to);
- board[to] = piece_of_color_and_type(us, promotion);
+ board[to] = make_piece(us, promotion);
// Update piece counts
pieceCount[us][promotion]++;
}
}
+ // Prefetch pawn and material hash tables
+ Threads[threadID].pawnTable.prefetch(st->pawnKey);
+ Threads[threadID].materialTable.prefetch(st->materialKey);
+
// Update incremental scores
st->value += pst_delta(piece, from, to);
if (ci.dcCandidates && bit_is_set(ci.dcCandidates, from))
{
if (pt != ROOK)
- st->checkersBB |= (attacks_from<ROOK>(ci.ksq) & pieces(ROOK, QUEEN, us));
+ st->checkersBB |= (attacks_from<ROOK>(king_square(them)) & pieces(ROOK, QUEEN, us));
if (pt != BISHOP)
- st->checkersBB |= (attacks_from<BISHOP>(ci.ksq) & pieces(BISHOP, QUEEN, us));
+ st->checkersBB |= (attacks_from<BISHOP>(king_square(them)) & pieces(BISHOP, QUEEN, us));
}
}
}
assert(to == st->epSquare);
assert(relative_rank(opposite_color(them), to) == RANK_6);
assert(piece_on(to) == PIECE_NONE);
- assert(piece_on(capsq) == piece_of_color_and_type(them, PAWN));
+ assert(piece_on(capsq) == make_piece(them, PAWN));
board[capsq] = PIECE_NONE;
}
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));
+ assert(piece_on(kfrom) == make_piece(us, KING));
+ assert(piece_on(rfrom) == make_piece(us, ROOK));
// Find destination squares for king and rook
if (rfrom > kfrom) // O-O
set_bit(&(byTypeBB[0]), rto); // HACK: byTypeBB[0] == occupied squares
// Update board array
- Piece king = piece_of_color_and_type(us, KING);
- Piece rook = piece_of_color_and_type(us, ROOK);
+ Piece king = make_piece(us, KING);
+ Piece rook = make_piece(us, ROOK);
board[kfrom] = board[rfrom] = PIECE_NONE;
board[kto] = king;
board[rto] = rook;
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) == piece_of_color_and_type(us, PAWN));
+ assert(!ep || piece_on(to) == make_piece(us, PAWN));
if (pm) // promotion ?
{
- PieceType promotion = move_promotion_piece(m);
+ PieceType promotion = promotion_piece_type(m);
pt = PAWN;
assert(promotion >= KNIGHT && promotion <= QUEEN);
- assert(piece_on(to) == piece_of_color_and_type(us, promotion));
+ assert(piece_on(to) == make_piece(us, promotion));
// Replace promoted piece with a pawn
clear_bit(&(byTypeBB[promotion]), to);
do_move_bb(&(byTypeBB[pt]), move_bb);
do_move_bb(&(byTypeBB[0]), move_bb); // HACK: byTypeBB[0] == occupied squares
- board[from] = piece_of_color_and_type(us, pt);
+ board[from] = make_piece(us, pt);
board[to] = PIECE_NONE;
// Update piece list
set_bit(&(byTypeBB[st->capturedType]), capsq);
set_bit(&(byTypeBB[0]), capsq);
- board[capsq] = piece_of_color_and_type(them, st->capturedType);
+ board[capsq] = make_piece(them, st->capturedType);
// Update piece count
pieceCount[them][st->capturedType]++;
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:
clear_bit(&(byColorBB[us]), kto);
// Update board
board[rto] = board[kto] = PIECE_NONE;
- board[rfrom] = piece_of_color_and_type(us, ROOK);
- board[kfrom] = piece_of_color_and_type(us, KING);
+ board[rfrom] = make_piece(us, ROOK);
+ board[kfrom] = make_piece(us, KING);
// Update piece lists
pieceList[us][KING][index[kto]] = kfrom;
void Position::do_null_move(StateInfo& backupSt) {
assert(is_ok());
- assert(!is_check());
+ assert(!in_check());
// Back up the information necessary to undo the null move to the supplied
// StateInfo object.
void Position::undo_null_move() {
assert(is_ok());
- assert(!is_check());
+ assert(!in_check());
// Restore information from the our backup StateInfo object
StateInfo* backupSt = st->previous;
/// move, and one which takes a 'from' and a 'to' square. The function does
/// not yet understand promotions captures.
-int Position::see(Move m) const {
-
- assert(move_is_ok(m));
- return see(move_from(m), move_to(m));
-}
-
int Position::see_sign(Move m) const {
assert(move_is_ok(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))
+ if (piece_value_midgame(piece_on(to)) >= piece_value_midgame(piece_on(from)))
return 1;
- return see(from, to);
+ return see(m);
}
-int Position::see(Square from, Square to) const {
+int Position::see(Move m) const {
+ Square from, to;
Bitboard occupied, attackers, stmAttackers, b;
int swapList[32], slIndex = 1;
PieceType capturedType, pt;
Color stm;
- assert(square_is_ok(from));
- assert(square_is_ok(to));
-
- capturedType = type_of_piece_on(to);
+ assert(move_is_ok(m));
- // King cannot be recaptured
- if (capturedType == KING)
- return seeValues[capturedType];
+ // As castle moves are implemented as capturing the rook, they have
+ // SEE == RookValueMidgame most of the times (unless the rook is under
+ // attack).
+ if (move_is_castle(m))
+ return 0;
+ from = move_from(m);
+ to = move_to(m);
+ capturedType = type_of_piece_on(to);
occupied = occupied_squares();
// Handle en passant moves
// 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<KNIGHT>(to) & pieces(KNIGHT))
- | (attacks_from<KING>(to) & pieces(KING))
- | (attacks_from<PAWN>(to, WHITE) & pieces(PAWN, BLACK))
- | (attacks_from<PAWN>(to, BLACK) & pieces(PAWN, WHITE));
+ attackers = attackers_to(to, occupied);
// If the opponent has no attackers we are finished
stm = opposite_color(color_of_piece_on(from));
stmAttackers = attackers & pieces_of_color(stm);
if (!stmAttackers)
- return seeValues[capturedType];
+ return PieceValueMidgame[capturedType];
// The destination square is defended, which makes things rather more
// difficult to compute. We proceed by building up a "swap list" containing
// 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.
- swapList[0] = seeValues[capturedType];
+ swapList[0] = PieceValueMidgame[capturedType];
capturedType = type_of_piece_on(from);
do {
// Add the new entry to the swap list
assert(slIndex < 32);
- swapList[slIndex] = -swapList[slIndex - 1] + seeValues[capturedType];
+ swapList[slIndex] = -swapList[slIndex - 1] + PieceValueMidgame[capturedType];
slIndex++;
// Remember the value of the capturing piece, and change the side to
}
-/// 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 <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() {
-
- st->gamePly = 0;
-}
-
-void Position::inc_startpos_ply_counter() {
-
- startPosPlyCounter++;
-}
-
/// Position::put_piece() puts a piece on the given square of the board,
/// updating the board array, pieces list, bitboards, and piece counts.
/// Position::is_draw() tests whether the position is drawn by material,
/// repetition, or the 50 moves rule. It does not detect stalemates, this
/// must be done by the search.
-
+template<bool SkipRepetition>
bool Position::is_draw() const {
// Draw by material?
return true;
// Draw by the 50 moves rule?
- if (st->rule50 > 99 && (st->rule50 > 100 || !is_mate()))
+ if (st->rule50 > 99 && !is_mate())
return true;
// Draw by repetition?
- 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;
+ if (!SkipRepetition)
+ 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;
}
+// Explicit template instantiations
+template bool Position::is_draw<false>() const;
+template bool Position::is_draw<true>() const;
+
/// Position::is_mate() returns true or false depending on whether the
/// side to move is checkmated.
bool Position::is_mate() const {
- MoveStack moves[MOVES_MAX];
- return is_check() && generate_moves(*this, moves) == moves;
-}
-
-
-/// Position::has_mate_threat() tests whether the side to move is under
-/// a threat of being mated in one from the current position.
-
-bool Position::has_mate_threat() {
-
- MoveStack mlist[MOVES_MAX], *last, *cur;
- StateInfo st1, st2;
- bool mateFound = false;
-
- // If we are under check it's up to evasions to do the job
- if (is_check())
- return false;
-
- // First pass the move to our opponent doing a null move
- do_null_move(st1);
-
- // Then generate pseudo-legal moves that could give check
- last = generate_non_capture_checks(*this, mlist);
- last = generate_captures(*this, last);
-
- // Loop through the moves, and see if one of them gives mate
- Bitboard pinned = pinned_pieces(sideToMove);
- CheckInfo ci(*this);
- for (cur = mlist; cur != last && !mateFound; cur++)
- {
- Move move = cur->move;
- if ( !pl_move_is_legal(move, pinned)
- || !move_is_check(move, ci))
- continue;
-
- do_move(move, st2, ci, true);
-
- if (is_mate())
- mateFound = true;
-
- undo_move(move);
- }
-
- undo_null_move();
- return mateFound;
+ MoveStack moves[MAX_MOVES];
+ return in_check() && generate<MV_LEGAL>(*this, moves) == moves;
}
-/// Position::init_zobrist() is a static member function which initializes at
-/// startup the various arrays used to compute hash keys.
+/// Position::init() is a static member function which initializes at
+/// startup the various arrays used to compute hash keys and the piece
+/// square tables. The latter 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_zobrist() {
+void Position::init() {
- int i,j, k;
RKISS rk;
- for (i = 0; i < 2; i++) for (j = 0; j < 8; j++) for (k = 0; k < 64; k++)
- zobrist[i][j][k] = rk.rand<Key>();
+ for (Color c = WHITE; c <= BLACK; c++)
+ for (PieceType pt = PAWN; pt <= KING; pt++)
+ for (Square s = SQ_A1; s <= SQ_H8; s++)
+ zobrist[c][pt][s] = rk.rand<Key>();
- for (i = 0; i < 64; i++)
- zobEp[i] = rk.rand<Key>();
+ for (Square s = SQ_A1; s <= SQ_H8; s++)
+ zobEp[s] = rk.rand<Key>();
- for (i = 0; i < 16; i++)
+ for (int i = 0; i < 16; i++)
zobCastle[i] = rk.rand<Key>();
zobSideToMove = rk.rand<Key>();
zobExclusion = rk.rand<Key>();
-}
-
-
-/// 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. 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() {
for (Square s = SQ_A1; s <= SQ_H8; s++)
for (Piece p = WP; p <= WK; p++)
}
-/// Position::flipped_copy() makes a copy of the input position, but with
-/// the white and black sides reversed. This is only useful for debugging,
-/// especially for finding evaluation symmetry bugs.
+/// Position::flip() flips position with 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::flip() {
- assert(pos.is_ok());
+ assert(is_ok());
+
+ // Make a copy of current position before to start changing
+ const Position pos(*this, threadID);
clear();
threadID = pos.thread();
sideToMove = opposite_color(pos.side_to_move());
// Castling rights
- 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);
+ if (pos.can_castle_kingside(WHITE)) set_castle_kingside(BLACK);
+ if (pos.can_castle_queenside(WHITE)) set_castle_queenside(BLACK);
+ if (pos.can_castle_kingside(BLACK)) set_castle_kingside(WHITE);
+ if (pos.can_castle_queenside(BLACK)) set_castle_queenside(WHITE);
initialKFile = pos.initialKFile;
initialKRFile = pos.initialKRFile;
if (failedStep) *failedStep = 1;
// Side to move OK?
- if (!color_is_ok(side_to_move()))
+ if (side_to_move() != WHITE && side_to_move() != BLACK)
return false;
// Are the king squares in the position correct?
// Castle files OK?
if (failedStep) (*failedStep)++;
- if (!file_is_ok(initialKRFile))
+ if (!square_is_ok(make_square(initialKRFile, RANK_1)))
return false;
- if (!file_is_ok(initialQRFile))
+ if (!square_is_ok(make_square(initialQRFile, RANK_1)))
return false;
// Do both sides have exactly one king?
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++)
{
- 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)) != piece_of_color_and_type(c, ROOK))
+ 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)) != piece_of_color_and_type(c, ROOK))
+
+ 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))
projects / stockfish / blobdiff