#include "rkiss.h"
#include "thread.h"
#include "tt.h"
-#include "ucioption.h"
using std::string;
using std::cout;
CheckInfo::CheckInfo(const Position& pos) {
- Color us = pos.side_to_move();
- Color them = opposite_color(us);
+ Color them = opposite_color(pos.side_to_move());
Square ksq = pos.king_square(them);
- dcCandidates = pos.discovered_check_candidates(us);
- pinned = pos.pinned_pieces(us);
+ pinned = pos.pinned_pieces();
+ dcCandidates = pos.discovered_check_candidates();
checkSq[PAWN] = pos.attacks_from<PAWN>(ksq, them);
checkSq[KNIGHT] = pos.attacks_from<KNIGHT>(ksq);
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;
+
+ assert(is_ok());
}
Position::Position(const string& fen, bool isChess960, int th) {
}
-/// 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
-}
-
-
/// Position::from_fen() initializes the position object with the given 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).
}
// 5-6. Halfmove clock and fullmove number
- fen >> std::skipws >> st->rule50 >> fullMoves;
+ fen >> std::skipws >> st->rule50 >> startPosPly;
+
+ // Convert from fullmove starting from 1 to ply starting from 0,
+ // handle also common incorrect FEN with fullmove = 0.
+ startPosPly = Max(2 * (startPosPly - 1), 0) + int(sideToMove == BLACK);
// Various initialisations
chess960 = isChess960;
st->value = compute_value();
st->npMaterial[WHITE] = compute_non_pawn_material(WHITE);
st->npMaterial[BLACK] = compute_non_pawn_material(BLACK);
+
+ assert(is_ok());
}
fen << '-';
fen << (ep_square() == SQ_NONE ? " -" : " " + square_to_string(ep_square()))
- << " " << st->rule50 << " " << fullMoves;
+ << " " << st->rule50 << " " << 1 + (startPosPly - int(sideToMove == BLACK)) / 2;
return fen.str();
}
/// 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.
+/// king) pieces for the given color. Or, when template parameter FindPinned is
+/// false, the function return the pieces of the given color candidate for a
+/// discovery check against the enemy king.
template<bool FindPinned>
-Bitboard Position::hidden_checkers(Color c) const {
-
- Bitboard result = EmptyBoardBB;
- Bitboard pinners = pieces(FindPinned ? opposite_color(c) : c);
-
- // Pinned pieces protect our king, dicovery checks attack
- // the enemy king.
- Square ksq = king_square(FindPinned ? c : opposite_color(c));
+Bitboard Position::hidden_checkers() const {
- // Pinners are sliders, not checkers, that give check when candidate pinned is removed
- pinners &= (pieces(ROOK, QUEEN) & RookPseudoAttacks[ksq]) | (pieces(BISHOP, QUEEN) & BishopPseudoAttacks[ksq]);
+ // Pinned pieces protect our king, dicovery checks attack the enemy king
+ Bitboard b, result = EmptyBoardBB;
+ Bitboard pinners = pieces(FindPinned ? opposite_color(sideToMove) : sideToMove);
+ Square ksq = king_square(FindPinned ? sideToMove : opposite_color(sideToMove));
- if (FindPinned && pinners)
- pinners &= ~st->checkersBB;
+ // Pinners are sliders, that give check when candidate pinned is removed
+ pinners &= (pieces(ROOK, QUEEN) & RookPseudoAttacks[ksq])
+ | (pieces(BISHOP, QUEEN) & BishopPseudoAttacks[ksq]);
while (pinners)
{
- Square s = pop_1st_bit(&pinners);
- Bitboard b = squares_between(s, ksq) & occupied_squares();
+ b = squares_between(ksq, pop_1st_bit(&pinners)) & occupied_squares();
- assert(b);
-
- if ( !(b & (b - 1)) // Only one bit set?
- && (b & pieces(c))) // Is an our piece?
+ // Only one bit set and is an our piece?
+ if (b && !(b & (b - 1)) && (b & pieces(sideToMove)))
result |= b;
}
return result;
/// 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.
+/// king) pieces for the side to move.
-Bitboard Position::pinned_pieces(Color c) const {
+Bitboard Position::pinned_pieces() const {
- return hidden_checkers<true>(c);
+ return hidden_checkers<true>();
}
/// 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.
+/// pieces for the side to move which are candidates for giving a discovered
+/// check.
-Bitboard Position::discovered_check_candidates(Color c) const {
+Bitboard Position::discovered_check_candidates() const {
- return hidden_checkers<false>(c);
+ return hidden_checkers<false>();
}
/// Position::attackers_to() computes a bitboard containing all pieces which
bool Position::pl_move_is_legal(Move m, Bitboard pinned) const {
- assert(is_ok());
assert(move_is_ok(m));
- assert(pinned == pinned_pieces(side_to_move()));
+ assert(pinned == pinned_pieces());
Color us = side_to_move();
Square from = move_from(m);
{
Color them = opposite_color(us);
Square to = move_to(m);
- Square capsq = to + Square(us == WHITE ? -8 : 8);
+ Square capsq = to + pawn_push(them);
Square ksq = king_square(us);
Bitboard b = occupied_squares();
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);
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(ci.dcCandidates == discovered_check_candidates());
assert(piece_color(piece_on(move_from(m))) == side_to_move());
Square from = move_from(m);
}
-/// 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;
-
- // Update the number of full moves after black's move
- if (sideToMove == BLACK)
- fullMoves++;
-
- 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;
-
- // 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.
void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveIsCheck) {
- assert(is_ok());
assert(move_is_ok(m));
assert(&newSt != st);
// 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];
+ int castleRights, rule50, pliesFromNull;
+ Score value;
+ Square epSquare;
};
memcpy(&newSt, st, sizeof(ReducedStateInfo));
newSt.previous = st;
st = &newSt;
- // Save the current key to the history[] array, in order to be able to
- // detect repetition draws.
- history[st->gamePly++] = key;
-
// Update side to move
key ^= zobSideToMove;
// Set en passant square, only if moved pawn can be captured
if ((to ^ from) == 16)
{
- if (attacks_from<PAWN>(from + (us == WHITE ? DELTA_N : DELTA_S), us) & pieces(PAWN, them))
+ if (attacks_from<PAWN>(from + pawn_push(us), us) & pieces(PAWN, them))
{
st->epSquare = Square((int(from) + int(to)) / 2);
key ^= zobEp[st->epSquare];
{
if (ep) // en passant ?
{
- capsq = (them == BLACK)? (to - DELTA_N) : (to - DELTA_S);
+ capsq = to + pawn_push(them);
assert(to == st->epSquare);
assert(relative_rank(opposite_color(them), to) == RANK_6);
void Position::undo_move(Move m) {
- assert(is_ok());
assert(move_is_ok(m));
sideToMove = opposite_color(sideToMove);
Square capsq = to;
if (ep)
- capsq = (us == WHITE)? (to - DELTA_N) : (to - DELTA_S);
+ capsq = to - pawn_push(us);
assert(st->capturedType != KING);
assert(!ep || square_is_empty(capsq));
void Position::do_null_move(StateInfo& backupSt) {
- assert(is_ok());
assert(!in_check());
// Back up the information necessary to undo the null move to the supplied
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[st->gamePly++] = st->key;
-
// Update the necessary information
if (st->epSquare != SQ_NONE)
st->key ^= zobEp[st->epSquare];
st->rule50++;
st->pliesFromNull = 0;
st->value += (sideToMove == WHITE) ? TempoValue : -TempoValue;
+
+ assert(is_ok());
}
void Position::undo_null_move() {
- assert(is_ok());
assert(!in_check());
// Restore information from the our backup StateInfo object
// Update the necessary information
sideToMove = opposite_color(sideToMove);
st->rule50--;
- st->gamePly--;
+
+ assert(is_ok());
}
// Handle en passant moves
if (st->epSquare == to && piece_type(piece_on(from)) == PAWN)
{
- Square capQq = (side_to_move() == WHITE ? to - DELTA_N : to - DELTA_S);
+ Square capQq = to - pawn_push(side_to_move());
assert(capturedType == PIECE_TYPE_NONE);
assert(piece_type(piece_on(capQq)) == PAWN);
castleRightsMask[sq] = ALL_CASTLES;
}
sideToMove = WHITE;
- fullMoves = 1;
nodes = 0;
}
// Draw by repetition?
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;
+ {
+ int i = 4, e = Min(st->rule50, st->pliesFromNull);
+
+ if (i <= e)
+ {
+ StateInfo* stp = st->previous->previous;
+
+ do {
+ stp = stp->previous->previous;
+
+ if (stp->key == st->key)
+ return true;
+
+ i +=2;
+
+ } while (i <= e);
+ }
+ }
return false;
}
void Position::flip() {
- assert(is_ok());
-
// Make a copy of current position before to start changing
const Position pos(*this, threadID);
projects / stockfish / blobdiff