#include <cassert>
#include <cstring>
-#include <fstream>
#include <iostream>
#include <sstream>
#include <algorithm>
using std::endl;
Key Position::zobrist[2][8][64];
-Key Position::zobEp[64];
+Key Position::zobEp[8];
Key Position::zobCastle[16];
Key Position::zobSideToMove;
Key Position::zobExclusion;
CheckInfo::CheckInfo(const Position& pos) {
- Color them = flip(pos.side_to_move());
- Square ksq = pos.king_square(them);
+ Color them = ~pos.side_to_move();
+ ksq = pos.king_square(them);
pinned = pos.pinned_pieces();
dcCandidates = pos.discovered_check_candidates();
// 1. Piece placement
while ((fen >> token) && !isspace(token))
{
- if (token == '/')
- sq -= Square(16); // Jump back of 2 rows
+ if (isdigit(token))
+ sq += Square(token - '0'); // Advance the given number of files
- else if (isdigit(token))
- sq += Square(token - '0'); // Skip the given number of files
+ else if (token == '/')
+ sq = make_square(FILE_A, rank_of(sq) - Rank(2));
else if ((p = PieceToChar.find(token)) != string::npos)
{
{
Square rsq;
Color c = islower(token) ? BLACK : WHITE;
- Piece rook = make_piece(c, ROOK);
token = char(toupper(token));
if (token == 'K')
- for (rsq = relative_square(c, SQ_H1); piece_on(rsq) != rook; rsq--) {}
+ for (rsq = relative_square(c, SQ_H1); type_of(piece_on(rsq)) != ROOK; rsq--) {}
else if (token == 'Q')
- for (rsq = relative_square(c, SQ_A1); piece_on(rsq) != rook; rsq++) {}
+ for (rsq = relative_square(c, SQ_A1); type_of(piece_on(rsq)) != ROOK; rsq++) {}
else if (token >= 'A' && token <= 'H')
rsq = make_square(File(token - 'A'), relative_rank(c, RANK_1));
else
continue;
- set_castle_right(king_square(c), rsq);
+ set_castle_right(c, rsq);
}
// 4. En passant square. Ignore if no pawn capture is possible
st->value = compute_value();
st->npMaterial[WHITE] = compute_non_pawn_material(WHITE);
st->npMaterial[BLACK] = compute_non_pawn_material(BLACK);
- st->checkersBB = attackers_to(king_square(sideToMove)) & pieces(flip(sideToMove));
+ st->checkersBB = attackers_to(king_square(sideToMove)) & pieces(~sideToMove);
chess960 = isChess960;
assert(pos_is_ok());
/// Position::set_castle_right() is an helper function used to set castling
-/// rights given the corresponding king and rook starting squares.
+/// rights given the corresponding color and the rook starting square.
-void Position::set_castle_right(Square ksq, Square rsq) {
+void Position::set_castle_right(Color c, Square rsq) {
- int f = (rsq < ksq ? WHITE_OOO : WHITE_OO) << color_of(piece_on(ksq));
+ int f = (rsq < king_square(c) ? WHITE_OOO : WHITE_OO) << c;
st->castleRights |= f;
- castleRightsMask[ksq] ^= f;
- castleRightsMask[rsq] ^= f;
+ castleRightsMask[king_square(c)] |= f;
+ castleRightsMask[rsq] |= f;
castleRookSquare[f] = rsq;
}
// Pinned pieces protect our king, dicovery checks attack the enemy king
Bitboard b, result = 0;
- Bitboard pinners = pieces(FindPinned ? flip(sideToMove) : sideToMove);
- Square ksq = king_square(FindPinned ? sideToMove : flip(sideToMove));
+ Bitboard pinners = pieces(FindPinned ? ~sideToMove : sideToMove);
+ Square ksq = king_square(FindPinned ? sideToMove : ~sideToMove);
// Pinners are sliders, that give check when candidate pinned is removed
- pinners &= (pieces(ROOK, QUEEN) & RookPseudoAttacks[ksq])
- | (pieces(BISHOP, QUEEN) & BishopPseudoAttacks[ksq]);
+ pinners &= (pieces(ROOK, QUEEN) & PseudoAttacks[ROOK][ksq])
+ | (pieces(BISHOP, QUEEN) & PseudoAttacks[BISHOP][ksq]);
while (pinners)
{
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_bb<ROOK>(s, occ) & pieces(ROOK, QUEEN))
+ | (attacks_bb<BISHOP>(s, occ) & pieces(BISHOP, QUEEN))
| (attacks_from<KING>(s) & pieces(KING));
}
switch (type_of(p))
{
- case BISHOP: return bishop_attacks_bb(s, occ);
- case ROOK : return rook_attacks_bb(s, occ);
- case QUEEN : return bishop_attacks_bb(s, occ) | rook_attacks_bb(s, occ);
+ case BISHOP: return attacks_bb<BISHOP>(s, occ);
+ case ROOK : return attacks_bb<ROOK>(s, occ);
+ case QUEEN : return attacks_bb<BISHOP>(s, occ) | attacks_bb<ROOK>(s, occ);
default : return StepAttacksBB[p][s];
}
}
assert(square_is_ok(s));
Bitboard occ, xray;
- Square from = move_from(m);
- Square to = move_to(m);
- Piece piece = piece_on(from);
+ Square from = from_sq(m);
+ Square to = to_sq(m);
+ Piece piece = piece_moved(m);
assert(!square_is_empty(from));
// Update occupancy as if the piece is moving
occ = occupied_squares();
- do_move_bb(&occ, make_move_bb(from, to));
+ occ ^= from;
+ occ ^= to;
// The piece moved in 'to' attacks the square 's' ?
- if (bit_is_set(attacks_from(piece, to, occ), s))
+ if (attacks_from(piece, to, occ) & s)
return true;
// Scan for possible X-ray attackers behind the moved piece
- xray = (rook_attacks_bb(s, occ) & pieces(ROOK, QUEEN, color_of(piece)))
- |(bishop_attacks_bb(s, occ) & pieces(BISHOP, QUEEN, color_of(piece)));
+ xray = (attacks_bb<ROOK>(s, occ) & pieces(ROOK, QUEEN, color_of(piece)))
+ |(attacks_bb<BISHOP>(s, occ) & pieces(BISHOP, QUEEN, color_of(piece)));
// Verify attackers are triggered by our move and not already existing
return xray && (xray ^ (xray & attacks_from<QUEEN>(s)));
assert(is_ok(m));
assert(pinned == pinned_pieces());
- Color us = side_to_move();
- Square from = move_from(m);
+ Color us = sideToMove;
+ Square from = from_sq(m);
- assert(color_of(piece_on(from)) == us);
+ assert(color_of(piece_moved(m)) == us);
assert(piece_on(king_square(us)) == make_piece(us, KING));
// En passant captures are a tricky special case. Because they are rather
// the move is made.
if (is_enpassant(m))
{
- Color them = flip(us);
- Square to = move_to(m);
+ Color them = ~us;
+ Square to = to_sq(m);
Square capsq = to + pawn_push(them);
Square ksq = king_square(us);
Bitboard b = occupied_squares();
assert(to == ep_square());
- assert(piece_on(from) == make_piece(us, PAWN));
+ assert(piece_moved(m) == make_piece(us, PAWN));
assert(piece_on(capsq) == make_piece(them, PAWN));
assert(piece_on(to) == NO_PIECE);
- clear_bit(&b, from);
- clear_bit(&b, capsq);
- set_bit(&b, to);
+ b ^= from;
+ b ^= capsq;
+ b |= to;
- return !(rook_attacks_bb(ksq, b) & pieces(ROOK, QUEEN, them))
- && !(bishop_attacks_bb(ksq, b) & pieces(BISHOP, QUEEN, them));
+ return !(attacks_bb<ROOK>(ksq, b) & pieces(ROOK, QUEEN, them))
+ && !(attacks_bb<BISHOP>(ksq, b) & pieces(BISHOP, QUEEN, them));
}
// If the moving piece is a king, check whether the destination
// square is attacked by the opponent. Castling moves are checked
// for legality during move generation.
if (type_of(piece_on(from)) == KING)
- return is_castle(m) || !(attackers_to(move_to(m)) & pieces(flip(us)));
+ return is_castle(m) || !(attackers_to(to_sq(m)) & pieces(~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 !pinned
- || !bit_is_set(pinned, from)
- || squares_aligned(from, move_to(m), king_square(us));
+ || !(pinned & from)
+ || squares_aligned(from, to_sq(m), king_square(us));
}
bool Position::is_pseudo_legal(const Move m) const {
Color us = sideToMove;
- Color them = flip(sideToMove);
- Square from = move_from(m);
- Square to = move_to(m);
- Piece pc = piece_on(from);
+ Color them = ~sideToMove;
+ Square from = from_sq(m);
+ Square to = to_sq(m);
+ Piece pc = piece_moved(m);
// Use a slower but simpler function for uncommon cases
if (is_special(m))
return false;
}
}
- else if (!bit_is_set(attacks_from(pc, from), to))
+ else if (!(attacks_from(pc, from) & to))
return false;
// Evasions generator already takes care to avoid some kind of illegal moves
{
// 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)
+ if (type_of(pc) == KING)
{
Bitboard b = occupied_squares();
- clear_bit(&b, from);
- if (attackers_to(move_to(m), b) & pieces(flip(us)))
+ b ^= from;
+ if (attackers_to(to, b) & pieces(~us))
return false;
}
else
// 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)))
+ if (!(target & to))
return false;
}
}
assert(is_ok(m));
assert(ci.dcCandidates == discovered_check_candidates());
- assert(color_of(piece_on(move_from(m))) == side_to_move());
+ assert(color_of(piece_moved(m)) == sideToMove);
- Square from = move_from(m);
- Square to = move_to(m);
+ Square from = from_sq(m);
+ Square to = to_sq(m);
PieceType pt = type_of(piece_on(from));
// Direct check ?
- if (bit_is_set(ci.checkSq[pt], to))
+ if (ci.checkSq[pt] & to)
return true;
// Discovery check ?
- if (ci.dcCandidates && bit_is_set(ci.dcCandidates, from))
+ if (ci.dcCandidates && (ci.dcCandidates & from))
{
// For pawn and king moves we need to verify also direction
if ( (pt != PAWN && pt != KING)
- || !squares_aligned(from, to, king_square(flip(side_to_move()))))
+ || !squares_aligned(from, to, king_square(~sideToMove)))
return true;
}
if (!is_special(m))
return false;
- Color us = side_to_move();
+ Color us = sideToMove;
Bitboard b = occupied_squares();
- Square ksq = king_square(flip(us));
+ Square ksq = king_square(~us);
// Promotion with check ?
if (is_promotion(m))
{
- clear_bit(&b, from);
- return bit_is_set(attacks_from(Piece(promotion_piece_type(m)), to, b), ksq);
+ b ^= from;
+ return attacks_from(Piece(promotion_piece_type(m)), to, b) & ksq;
}
// En passant capture with check ? We have already handled the case
if (is_enpassant(m))
{
Square capsq = make_square(file_of(to), rank_of(from));
- clear_bit(&b, from);
- clear_bit(&b, capsq);
- set_bit(&b, to);
- return (rook_attacks_bb(ksq, b) & pieces(ROOK, QUEEN, us))
- ||(bishop_attacks_bb(ksq, b) & pieces(BISHOP, QUEEN, us));
+ b ^= from;
+ b ^= capsq;
+ b |= to;
+ return (attacks_bb<ROOK>(ksq, b) & pieces(ROOK, QUEEN, us))
+ ||(attacks_bb<BISHOP>(ksq, b) & pieces(BISHOP, QUEEN, us));
}
// Castling with check ?
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);
+ b ^= kfrom;
+ b ^= rfrom;
+ b |= rto;
+ b |= kto;
+ return attacks_bb<ROOK>(rto, b) & ksq;
}
return false;
k ^= zobSideToMove;
// Increment the 50 moves rule draw counter. Resetting it to zero in the
- // case of non-reversible moves is taken care of later.
+ // case of a capture or a pawn move is taken care of later.
st->rule50++;
st->pliesFromNull++;
return;
}
- Color us = side_to_move();
- Color them = flip(us);
- Square from = move_from(m);
- Square to = move_to(m);
+ Color us = sideToMove;
+ Color them = ~us;
+ Square from = from_sq(m);
+ Square to = to_sq(m);
Piece piece = piece_on(from);
PieceType pt = type_of(piece);
PieceType capture = is_enpassant(m) ? PAWN : type_of(piece_on(to));
st->npMaterial[them] -= PieceValueMidgame[capture];
// Remove the captured piece
- clear_bit(&byColorBB[them], capsq);
- clear_bit(&byTypeBB[capture], capsq);
- clear_bit(&occupied, capsq);
+ byColorBB[them] ^= capsq;
+ byTypeBB[capture] ^= capsq;
+ occupied ^= capsq;
// Update piece list, move the last piece at index[capsq] position and
// shrink the list.
// Reset en passant square
if (st->epSquare != SQ_NONE)
{
- k ^= zobEp[st->epSquare];
+ k ^= zobEp[file_of(st->epSquare)];
st->epSquare = SQ_NONE;
}
// Update castle rights if needed
- if ( st->castleRights != CASTLES_NONE
- && (castleRightsMask[from] & castleRightsMask[to]) != ALL_CASTLES)
+ if (st->castleRights && (castleRightsMask[from] | castleRightsMask[to]))
{
- k ^= zobCastle[st->castleRights];
- st->castleRights &= castleRightsMask[from] & castleRightsMask[to];
- k ^= zobCastle[st->castleRights];
+ int cr = castleRightsMask[from] | castleRightsMask[to];
+ k ^= zobCastle[st->castleRights & cr];
+ st->castleRights &= ~cr;
}
// Prefetch TT access as soon as we know key is updated
prefetch((char*)TT.first_entry(k));
// 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(&occupied, move_bb);
+ Bitboard from_to_bb = SquareBB[from] | SquareBB[to];
+ byColorBB[us] ^= from_to_bb;
+ byTypeBB[pt] ^= from_to_bb;
+ occupied ^= from_to_bb;
board[to] = board[from];
board[from] = NO_PIECE;
&& (attacks_from<PAWN>(from + pawn_push(us), us) & pieces(PAWN, them)))
{
st->epSquare = Square((from + to) / 2);
- k ^= zobEp[st->epSquare];
+ k ^= zobEp[file_of(st->epSquare)];
}
if (is_promotion(m))
assert(promotion >= KNIGHT && promotion <= QUEEN);
// Replace the pawn with the promoted piece
- clear_bit(&byTypeBB[PAWN], to);
- set_bit(&byTypeBB[promotion], to);
+ byTypeBB[PAWN] ^= to;
+ byTypeBB[promotion] |= to;
board[to] = make_piece(us, promotion);
// Update piece lists, move the last pawn at index[to] position
else
{
// Direct checks
- if (bit_is_set(ci.checkSq[pt], to))
- st->checkersBB = SetMaskBB[to];
+ if (ci.checkSq[pt] & to)
+ st->checkersBB |= to;
// Discovery checks
- if (ci.dcCandidates && bit_is_set(ci.dcCandidates, from))
+ if (ci.dcCandidates && (ci.dcCandidates & from))
{
if (pt != ROOK)
st->checkersBB |= attacks_from<ROOK>(king_square(them)) & pieces(ROOK, QUEEN, us);
}
// Finish
- sideToMove = flip(sideToMove);
+ sideToMove = ~sideToMove;
st->value += (sideToMove == WHITE ? TempoValue : -TempoValue);
assert(pos_is_ok());
assert(is_ok(m));
- sideToMove = flip(sideToMove);
+ sideToMove = ~sideToMove;
if (is_castle(m))
{
return;
}
- Color us = side_to_move();
- Color them = flip(us);
- Square from = move_from(m);
- Square to = move_to(m);
+ Color us = sideToMove;
+ Color them = ~us;
+ Square from = from_sq(m);
+ Square to = to_sq(m);
Piece piece = piece_on(to);
PieceType pt = type_of(piece);
PieceType capture = st->capturedType;
assert(promotion >= KNIGHT && promotion <= QUEEN);
// Replace the promoted piece with the pawn
- clear_bit(&byTypeBB[promotion], to);
- set_bit(&byTypeBB[PAWN], to);
+ byTypeBB[promotion] ^= to;
+ byTypeBB[PAWN] |= to;
board[to] = make_piece(us, PAWN);
// Update piece lists, move the last promoted piece at index[to] position
}
// 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(&occupied, move_bb);
+ Bitboard from_to_bb = SquareBB[from] | SquareBB[to];
+ byColorBB[us] ^= from_to_bb;
+ byTypeBB[pt] ^= from_to_bb;
+ occupied ^= from_to_bb;
board[from] = board[to];
board[to] = NO_PIECE;
}
// Restore the captured piece
- set_bit(&byColorBB[them], capsq);
- set_bit(&byTypeBB[capture], capsq);
- set_bit(&occupied, capsq);
+ byColorBB[them] |= capsq;
+ byTypeBB[capture] |= capsq;
+ occupied |= capsq;
board[capsq] = make_piece(them, capture);
Square kto, kfrom, rfrom, rto, kAfter, rAfter;
- Color us = side_to_move();
- Square kBefore = move_from(m);
- Square rBefore = move_to(m);
+ Color us = sideToMove;
+ Square kBefore = from_sq(m);
+ Square rBefore = to_sq(m);
// Find after-castle squares for king and rook
if (rBefore > kBefore) // O-O
assert(piece_on(rfrom) == make_piece(us, ROOK));
// Remove pieces from source squares
- clear_bit(&byColorBB[us], kfrom);
- clear_bit(&byTypeBB[KING], kfrom);
- clear_bit(&occupied, kfrom);
- clear_bit(&byColorBB[us], rfrom);
- clear_bit(&byTypeBB[ROOK], rfrom);
- clear_bit(&occupied, rfrom);
+ byColorBB[us] ^= kfrom;
+ byTypeBB[KING] ^= kfrom;
+ occupied ^= kfrom;
+ byColorBB[us] ^= rfrom;
+ byTypeBB[ROOK] ^= rfrom;
+ occupied ^= rfrom;
// Put pieces on destination squares
- set_bit(&byColorBB[us], kto);
- set_bit(&byTypeBB[KING], kto);
- set_bit(&occupied, kto);
- set_bit(&byColorBB[us], rto);
- set_bit(&byTypeBB[ROOK], rto);
- set_bit(&occupied, rto);
+ byColorBB[us] |= kto;
+ byTypeBB[KING] |= kto;
+ occupied |= kto;
+ byColorBB[us] |= rto;
+ byTypeBB[ROOK] |= rto;
+ occupied |= rto;
// Update board
Piece king = make_piece(us, KING);
// Clear en passant square
if (st->epSquare != SQ_NONE)
{
- st->key ^= zobEp[st->epSquare];
+ st->key ^= zobEp[file_of(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;
+ st->key ^= zobCastle[st->castleRights & castleRightsMask[kfrom]];
+ st->castleRights &= ~castleRightsMask[kfrom];
// Update checkers BB
- st->checkersBB = attackers_to(king_square(flip(us))) & pieces(us);
+ st->checkersBB = attackers_to(king_square(~us)) & pieces(us);
// Finish
- sideToMove = flip(sideToMove);
+ sideToMove = ~sideToMove;
st->value += (sideToMove == WHITE ? TempoValue : -TempoValue);
}
else
dst->rule50 = src->rule50;
dst->pliesFromNull = src->pliesFromNull;
- sideToMove = flip(sideToMove);
+ sideToMove = ~sideToMove;
if (Do)
{
if (st->epSquare != SQ_NONE)
- st->key ^= zobEp[st->epSquare];
+ st->key ^= zobEp[file_of(st->epSquare)];
st->key ^= zobSideToMove;
prefetch((char*)TT.first_entry(st->key));
assert(is_ok(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 (PieceValueMidgame[piece_on(to)] >= PieceValueMidgame[piece_on(from)])
+ if (PieceValueMidgame[piece_on(to_sq(m))] >= PieceValueMidgame[piece_moved(m)])
return 1;
return see(m);
if (is_castle(m))
return 0;
- from = move_from(m);
- to = move_to(m);
+ from = from_sq(m);
+ to = to_sq(m);
capturedType = type_of(piece_on(to));
occ = occupied_squares();
// Handle en passant moves
if (is_enpassant(m))
{
- Square capQq = to - pawn_push(side_to_move());
+ Square capQq = to - pawn_push(sideToMove);
- assert(capturedType == NO_PIECE_TYPE);
+ assert(!capturedType);
assert(type_of(piece_on(capQq)) == PAWN);
// Remove the captured pawn
- clear_bit(&occ, capQq);
+ occ ^= capQq;
capturedType = PAWN;
}
// Find all attackers to the destination square, with the moving piece
// removed, but possibly an X-ray attacker added behind it.
- clear_bit(&occ, from);
+ occ ^= from;
attackers = attackers_to(to, occ);
// If the opponent has no attackers we are finished
- stm = flip(color_of(piece_on(from)));
+ stm = ~color_of(piece_on(from));
stmAttackers = attackers & pieces(stm);
if (!stmAttackers)
return PieceValueMidgame[capturedType];
// and scan for new X-ray attacks behind the attacker.
b = stmAttackers & pieces(pt);
occ ^= (b & (~b + 1));
- attackers |= (rook_attacks_bb(to, occ) & pieces(ROOK, QUEEN))
- | (bishop_attacks_bb(to, occ) & pieces(BISHOP, QUEEN));
+ attackers |= (attacks_bb<ROOK>(to, occ) & pieces(ROOK, QUEEN))
+ | (attacks_bb<BISHOP>(to, occ) & pieces(BISHOP, QUEEN));
attackers &= occ; // Cut out pieces we've already done
// Remember the value of the capturing piece, and change the side to
// move before beginning the next iteration.
capturedType = pt;
- stm = flip(stm);
+ stm = ~stm;
stmAttackers = attackers & pieces(stm);
// Stop before processing a king capture
void Position::clear() {
+ memset(this, 0, sizeof(Position));
+ startState.epSquare = SQ_NONE;
st = &startState;
- memset(st, 0, sizeof(StateInfo));
- st->epSquare = SQ_NONE;
-
- 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 < 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++)
- {
board[sq] = NO_PIECE;
- castleRightsMask[sq] = ALL_CASTLES;
- }
- sideToMove = WHITE;
- nodes = 0;
- occupied = 0;
}
index[s] = pieceCount[c][pt]++;
pieceList[c][pt][index[s]] = s;
- set_bit(&byTypeBB[pt], s);
- set_bit(&byColorBB[c], s);
- set_bit(&occupied, s);
+ byTypeBB[pt] |= s;
+ byColorBB[c] |= s;
+ occupied |= s;
}
result ^= zobrist[color_of(piece_on(s))][type_of(piece_on(s))][s];
if (ep_square() != SQ_NONE)
- result ^= zobEp[ep_square()];
+ result ^= zobEp[file_of(ep_square())];
- if (side_to_move() == BLACK)
+ if (sideToMove == BLACK)
result ^= zobSideToMove;
return result;
result += pst(make_piece(c, pt), pop_1st_bit(&b));
}
- result += (side_to_move() == WHITE ? TempoValue / 2 : -TempoValue / 2);
+ result += (sideToMove == WHITE ? TempoValue / 2 : -TempoValue / 2);
return result;
}
return true;
// Draw by the 50 moves rule?
- if (st->rule50 > 99 && !is_mate())
+ if (st->rule50 > 99 && (!in_check() || MoveList<MV_LEGAL>(*this).size()))
return true;
// Draw by repetition?
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 {
-
- return in_check() && !MoveList<MV_LEGAL>(*this).size();
-}
-
-
/// 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
for (Square s = SQ_A1; s <= SQ_H8; s++)
zobrist[c][pt][s] = rk.rand<Key>();
- for (Square s = SQ_A1; s <= SQ_H8; s++)
- zobEp[s] = rk.rand<Key>();
+ for (File f = FILE_A; f <= FILE_H; f++)
+ zobEp[f] = rk.rand<Key>();
- for (int i = 0; i < 16; i++)
- zobCastle[i] = rk.rand<Key>();
+ for (int cr = CASTLES_NONE; cr <= ALL_CASTLES; cr++)
+ {
+ Bitboard b = cr;
+ while (b)
+ {
+ Key k = zobCastle[1 << pop_1st_bit(&b)];
+ zobCastle[cr] ^= k ? k : rk.rand<Key>();
+ }
+ }
zobSideToMove = rk.rand<Key>();
zobExclusion = rk.rand<Key>();
for (Square s = SQ_A1; s <= SQ_H8; s++)
{
pieceSquareTable[p][s] = ps + PSQT[p][s];
- pieceSquareTable[p+8][flip(s)] = -pieceSquareTable[p][s];
+ pieceSquareTable[p+8][~s] = -pieceSquareTable[p][s];
}
}
}
// Board
for (Square s = SQ_A1; s <= SQ_H8; s++)
if (!pos.square_is_empty(s))
- put_piece(Piece(pos.piece_on(s) ^ 8), flip(s));
+ put_piece(Piece(pos.piece_on(s) ^ 8), ~s);
// Side to move
- sideToMove = flip(pos.side_to_move());
+ sideToMove = ~pos.side_to_move();
// Castling rights
if (pos.can_castle(WHITE_OO))
- set_castle_right(king_square(BLACK), flip(pos.castle_rook_square(WHITE_OO)));
+ set_castle_right(BLACK, ~pos.castle_rook_square(WHITE_OO));
if (pos.can_castle(WHITE_OOO))
- set_castle_right(king_square(BLACK), flip(pos.castle_rook_square(WHITE_OOO)));
+ set_castle_right(BLACK, ~pos.castle_rook_square(WHITE_OOO));
if (pos.can_castle(BLACK_OO))
- set_castle_right(king_square(WHITE), flip(pos.castle_rook_square(BLACK_OO)));
+ set_castle_right(WHITE, ~pos.castle_rook_square(BLACK_OO));
if (pos.can_castle(BLACK_OOO))
- set_castle_right(king_square(WHITE), flip(pos.castle_rook_square(BLACK_OOO)));
+ set_castle_right(WHITE, ~pos.castle_rook_square(BLACK_OOO));
// En passant square
if (pos.st->epSquare != SQ_NONE)
- st->epSquare = flip(pos.st->epSquare);
+ st->epSquare = ~pos.st->epSquare;
// Checkers
- st->checkersBB = attackers_to(king_square(sideToMove)) & pieces(flip(sideToMove));
+ st->checkersBB = attackers_to(king_square(sideToMove)) & pieces(~sideToMove);
// Hash keys
st->key = compute_key();
if (failedStep) *failedStep = 1;
// Side to move OK?
- if (side_to_move() != WHITE && side_to_move() != BLACK)
+ if (sideToMove != WHITE && sideToMove != BLACK)
return false;
// Are the king squares in the position correct?
if (failedStep) (*failedStep)++;
if (debugKingCapture)
{
- Color us = side_to_move();
- Color them = flip(us);
+ Color us = sideToMove;
+ Color them = ~us;
Square ksq = king_square(them);
if (attackers_to(ksq) & pieces(us))
return false;
// Is there more than 2 checkers?
if (failedStep) (*failedStep)++;
- if (debugCheckerCount && count_1s<CNT32>(st->checkersBB) > 2)
+ if (debugCheckerCount && popcount<Full>(st->checkersBB) > 2)
return false;
// Bitboards OK?
if (debugBitboards)
{
// The intersection of the white and black pieces must be empty
- if (!(pieces(WHITE) & pieces(BLACK)))
+ if (pieces(WHITE) & pieces(BLACK))
return false;
// The union of the white and black pieces must be equal to all
{
// The en passant square must be on rank 6, from the point of view of the
// side to move.
- if (relative_rank(side_to_move(), ep_square()) != RANK_6)
+ if (relative_rank(sideToMove, ep_square()) != RANK_6)
return false;
}
if (debugPieceCounts)
for (Color c = WHITE; c <= BLACK; c++)
for (PieceType pt = PAWN; pt <= KING; pt++)
- if (pieceCount[c][pt] != count_1s<CNT32>(pieces(pt, c)))
+ if (pieceCount[c][pt] != popcount<Full>(pieces(pt, c)))
return false;
if (failedStep) (*failedStep)++;
Piece rook = (f & (WHITE_OO | WHITE_OOO) ? W_ROOK : B_ROOK);
- if ( castleRightsMask[castleRookSquare[f]] != (ALL_CASTLES ^ f)
- || piece_on(castleRookSquare[f]) != rook)
+ if ( piece_on(castleRookSquare[f]) != rook
+ || castleRightsMask[castleRookSquare[f]] != f)
return false;
}