#include "bitcount.h"
#include "movegen.h"
+#include "notation.h"
#include "position.h"
#include "psqtab.h"
#include "rkiss.h"
using std::cout;
using std::endl;
-Key Position::zobrist[2][8][64];
-Key Position::zobEp[8];
-Key Position::zobCastle[16];
-Key Position::zobSideToMove;
-Key Position::zobExclusion;
-
-Score Position::pieceSquareTable[16][64];
+// To convert a Piece to and from a FEN char
+static const string PieceToChar(" PNBRQK pnbrqk");
// Material values arrays, indexed by Piece
const Value PieceValueMidgame[17] = {
RookValueEndgame, QueenValueEndgame
};
-// To convert a Piece to and from a FEN char
-static const string PieceToChar(" PNBRQK pnbrqk");
+CACHE_LINE_ALIGNMENT
+
+Score pieceSquareTable[16][64];
+
+namespace Zobrist {
+
+Key psq[2][8][64]; // [color][pieceType][square]/[piece count]
+Key enpassant[8]; // [file]
+Key castle[16]; // [castleRight]
+Key side;
+Key exclusion;
+
+/// init() 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 PSQT[] tables. Second, the black
+/// halves of the tables are initialized by flipping and changing the sign of
+/// the white scores.
+
+void init() {
+
+ RKISS rk;
+
+ for (Color c = WHITE; c <= BLACK; c++)
+ for (PieceType pt = PAWN; pt <= KING; pt++)
+ for (Square s = SQ_A1; s <= SQ_H8; s++)
+ psq[c][pt][s] = rk.rand<Key>();
+
+ for (File f = FILE_A; f <= FILE_H; f++)
+ enpassant[f] = rk.rand<Key>();
+
+ for (int cr = CASTLES_NONE; cr <= ALL_CASTLES; cr++)
+ {
+ Bitboard b = cr;
+ while (b)
+ {
+ Key k = castle[1ULL << pop_lsb(&b)];
+ castle[cr] ^= k ? k : rk.rand<Key>();
+ }
+ }
+
+ side = rk.rand<Key>();
+ exclusion = rk.rand<Key>();
+
+ for (PieceType pt = PAWN; pt <= KING; pt++)
+ {
+ Score v = make_score(PieceValueMidgame[pt], PieceValueEndgame[pt]);
+
+ for (Square s = SQ_A1; s <= SQ_H8; s++)
+ {
+ pieceSquareTable[make_piece(WHITE, pt)][ s] = (v + PSQT[pt][s]);
+ pieceSquareTable[make_piece(BLACK, pt)][~s] = -(v + PSQT[pt][s]);
+ }
+ }
+}
+
+} // namespace Zobrist
/// CheckInfo c'tor
/// object do not depend on any external data so we detach state pointer from
/// the source one.
-void Position::operator=(const Position& pos) {
+Position& Position::operator=(const Position& pos) {
memcpy(this, &pos, sizeof(Position));
startState = *st;
nodes = 0;
assert(pos_is_ok());
+
+ return *this;
}
while (pinners)
{
- b = between_bb(ksq, pop_1st_bit(&pinners)) & pieces();
+ b = between_bb(ksq, pop_lsb(&pinners)) & pieces();
if (b && !more_than_one(b) && (b & pieces(sideToMove)))
result |= b;
if (type_of(pc) != KING)
{
Bitboard b = checkers();
- Square checksq = pop_1st_bit(&b);
+ Square checksq = pop_lsb(&b);
if (b) // double check ? In this case a king move is required
return false;
st = &newSt;
// Update side to move
- k ^= zobSideToMove;
+ k ^= Zobrist::side;
// Increment the 50 moves rule draw counter. Resetting it to zero in the
// case of a capture or a pawn move is taken care of later.
board[capsq] = NO_PIECE;
}
- st->pawnKey ^= zobrist[them][PAWN][capsq];
+ st->pawnKey ^= Zobrist::psq[them][PAWN][capsq];
}
else
st->npMaterial[them] -= PieceValueMidgame[capture];
pieceList[them][capture][pieceCount[them][capture]] = SQ_NONE;
// Update hash keys
- k ^= zobrist[them][capture][capsq];
- st->materialKey ^= zobrist[them][capture][pieceCount[them][capture]];
+ k ^= Zobrist::psq[them][capture][capsq];
+ st->materialKey ^= Zobrist::psq[them][capture][pieceCount[them][capture]];
// Update incremental scores
st->psqScore -= pieceSquareTable[make_piece(them, capture)][capsq];
}
// Update hash key
- k ^= zobrist[us][pt][from] ^ zobrist[us][pt][to];
+ k ^= Zobrist::psq[us][pt][from] ^ Zobrist::psq[us][pt][to];
// Reset en passant square
if (st->epSquare != SQ_NONE)
{
- k ^= zobEp[file_of(st->epSquare)];
+ k ^= Zobrist::enpassant[file_of(st->epSquare)];
st->epSquare = SQ_NONE;
}
if (st->castleRights && (castleRightsMask[from] | castleRightsMask[to]))
{
int cr = castleRightsMask[from] | castleRightsMask[to];
- k ^= zobCastle[st->castleRights & cr];
+ k ^= Zobrist::castle[st->castleRights & cr];
st->castleRights &= ~cr;
}
&& (attacks_from<PAWN>(from + pawn_push(us), us) & pieces(them, PAWN)))
{
st->epSquare = Square((from + to) / 2);
- k ^= zobEp[file_of(st->epSquare)];
+ k ^= Zobrist::enpassant[file_of(st->epSquare)];
}
if (type_of(m) == PROMOTION)
pieceList[us][promotion][index[to]] = to;
// Update hash keys
- k ^= zobrist[us][PAWN][to] ^ zobrist[us][promotion][to];
- st->pawnKey ^= zobrist[us][PAWN][to];
- st->materialKey ^= zobrist[us][promotion][pieceCount[us][promotion]++]
- ^ zobrist[us][PAWN][pieceCount[us][PAWN]];
+ k ^= Zobrist::psq[us][PAWN][to] ^ Zobrist::psq[us][promotion][to];
+ st->pawnKey ^= Zobrist::psq[us][PAWN][to];
+ st->materialKey ^= Zobrist::psq[us][promotion][pieceCount[us][promotion]++]
+ ^ Zobrist::psq[us][PAWN][pieceCount[us][PAWN]];
// Update incremental score
st->psqScore += pieceSquareTable[make_piece(us, promotion)][to]
}
// Update pawn hash key
- st->pawnKey ^= zobrist[us][PAWN][from] ^ zobrist[us][PAWN][to];
+ st->pawnKey ^= Zobrist::psq[us][PAWN][from] ^ Zobrist::psq[us][PAWN][to];
// Reset rule 50 draw counter
st->rule50 = 0;
st->psqScore += psq_delta(rook, rfrom, rto);
// Update hash key
- st->key ^= zobrist[us][KING][kfrom] ^ zobrist[us][KING][kto];
- st->key ^= zobrist[us][ROOK][rfrom] ^ zobrist[us][ROOK][rto];
+ st->key ^= Zobrist::psq[us][KING][kfrom] ^ Zobrist::psq[us][KING][kto];
+ st->key ^= Zobrist::psq[us][ROOK][rfrom] ^ Zobrist::psq[us][ROOK][rto];
// Clear en passant square
if (st->epSquare != SQ_NONE)
{
- st->key ^= zobEp[file_of(st->epSquare)];
+ st->key ^= Zobrist::enpassant[file_of(st->epSquare)];
st->epSquare = SQ_NONE;
}
// Update castling rights
- st->key ^= zobCastle[st->castleRights & castleRightsMask[kfrom]];
+ st->key ^= Zobrist::castle[st->castleRights & castleRightsMask[kfrom]];
st->castleRights &= ~castleRightsMask[kfrom];
// Update checkers BB
if (Do)
{
if (st->epSquare != SQ_NONE)
- st->key ^= zobEp[file_of(st->epSquare)];
+ st->key ^= Zobrist::enpassant[file_of(st->epSquare)];
- st->key ^= zobSideToMove;
+ st->key ^= Zobrist::side;
prefetch((char*)TT.first_entry(st->key));
st->epSquare = SQ_NONE;
Key Position::compute_key() const {
- Key k = zobCastle[st->castleRights];
+ Key k = Zobrist::castle[st->castleRights];
for (Bitboard b = pieces(); b; )
{
- Square s = pop_1st_bit(&b);
- k ^= zobrist[color_of(piece_on(s))][type_of(piece_on(s))][s];
+ Square s = pop_lsb(&b);
+ k ^= Zobrist::psq[color_of(piece_on(s))][type_of(piece_on(s))][s];
}
if (ep_square() != SQ_NONE)
- k ^= zobEp[file_of(ep_square())];
+ k ^= Zobrist::enpassant[file_of(ep_square())];
if (sideToMove == BLACK)
- k ^= zobSideToMove;
+ k ^= Zobrist::side;
return k;
}
for (Bitboard b = pieces(PAWN); b; )
{
- Square s = pop_1st_bit(&b);
- k ^= zobrist[color_of(piece_on(s))][PAWN][s];
+ Square s = pop_lsb(&b);
+ k ^= Zobrist::psq[color_of(piece_on(s))][PAWN][s];
}
return k;
for (Color c = WHITE; c <= BLACK; c++)
for (PieceType pt = PAWN; pt <= QUEEN; pt++)
for (int cnt = 0; cnt < piece_count(c, pt); cnt++)
- k ^= zobrist[c][pt][cnt];
+ k ^= Zobrist::psq[c][pt][cnt];
return k;
}
for (Bitboard b = pieces(); b; )
{
- Square s = pop_1st_bit(&b);
+ Square s = pop_lsb(&b);
score += pieceSquareTable[piece_on(s)][s];
}
template bool Position::is_draw<true>() const;
-/// 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 PSQT[] tables. Second, the black halves of the tables are
-/// initialized by flipping and changing the sign of the white scores.
-
-void Position::init() {
-
- RKISS rk;
-
- 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 (File f = FILE_A; f <= FILE_H; f++)
- zobEp[f] = rk.rand<Key>();
-
- for (int cr = CASTLES_NONE; cr <= ALL_CASTLES; cr++)
- {
- Bitboard b = cr;
- while (b)
- {
- Key k = zobCastle[1ULL << pop_1st_bit(&b)];
- zobCastle[cr] ^= k ? k : rk.rand<Key>();
- }
- }
-
- zobSideToMove = rk.rand<Key>();
- zobExclusion = rk.rand<Key>();
-
- for (PieceType pt = PAWN; pt <= KING; pt++)
- {
- Score v = make_score(PieceValueMidgame[pt], PieceValueEndgame[pt]);
-
- for (Square s = SQ_A1; s <= SQ_H8; s++)
- {
- pieceSquareTable[make_piece(WHITE, pt)][ s] = (v + PSQT[pt][s]);
- pieceSquareTable[make_piece(BLACK, pt)][~s] = -(v + PSQT[pt][s]);
- }
- }
-}
-
-
/// Position::flip() flips position with the white and black sides reversed. This
/// is only useful for debugging especially for finding evaluation symmetry bugs.