along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <algorithm>
#include <cassert>
#include <cstring>
#include <iomanip>
-#include <iostream>
#include <sstream>
-#include <algorithm>
#include "bitcount.h"
#include "movegen.h"
#include "tt.h"
using std::string;
-using std::cout;
-using std::endl;
static const string PieceToChar(" PNBRQK pnbrqk");
Color them = ~pos.side_to_move();
ksq = pos.king_square(them);
- pinned = pos.pinned_pieces();
+ pinned = pos.pinned_pieces(pos.side_to_move());
dcCandidates = pos.discovered_check_candidates();
checkSq[PAWN] = pos.attacks_from<PAWN>(ksq, them);
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++)
+ 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<Key>();
- for (File f = FILE_A; f <= FILE_H; f++)
+ for (File f = FILE_A; f <= FILE_H; ++f)
Zobrist::enpassant[f] = rk.rand<Key>();
- for (int cr = CASTLES_NONE; cr <= ALL_CASTLES; cr++)
+ for (int cr = CASTLES_NONE; cr <= ALL_CASTLES; ++cr)
{
Bitboard b = cr;
while (b)
Zobrist::side = rk.rand<Key>();
Zobrist::exclusion = rk.rand<Key>();
- for (PieceType pt = PAWN; pt <= KING; pt++)
+ for (PieceType pt = PAWN; pt <= KING; ++pt)
{
PieceValue[MG][make_piece(BLACK, pt)] = PieceValue[MG][pt];
PieceValue[EG][make_piece(BLACK, pt)] = PieceValue[EG][pt];
Score v = make_score(PieceValue[MG][pt], PieceValue[EG][pt]);
- for (Square s = SQ_A1; s <= SQ_H8; s++)
+ for (Square s = SQ_A1; s <= SQ_H8; ++s)
{
psq[WHITE][pt][ s] = (v + PSQT[pt][s]);
psq[BLACK][pt][~s] = -(v + PSQT[pt][s]);
else if ((p = PieceToChar.find(token)) != string::npos)
{
put_piece(sq, color_of(Piece(p)), type_of(Piece(p)));
- sq++;
+ ++sq;
}
}
token = char(toupper(token));
if (token == 'K')
- for (rsq = relative_square(c, SQ_H1); type_of(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); type_of(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 = File(token - 'A') | relative_rank(c, RANK_1);
Square kto = relative_square(c, cs == KING_SIDE ? SQ_G1 : SQ_C1);
Square rto = relative_square(c, cs == KING_SIDE ? SQ_F1 : SQ_D1);
- for (Square s = std::min(rfrom, rto); s <= std::max(rfrom, rto); s++)
+ for (Square s = std::min(rfrom, rto); s <= std::max(rfrom, rto); ++s)
if (s != kfrom && s != rfrom)
castlePath[c][cs] |= s;
- for (Square s = std::min(kfrom, kto); s <= std::max(kfrom, kto); s++)
+ for (Square s = std::min(kfrom, kto); s <= std::max(kfrom, kto); ++s)
if (s != kfrom && s != rfrom)
castlePath[c][cs] |= s;
}
std::ostringstream ss;
- for (Rank rank = RANK_8; rank >= RANK_1; rank--)
+ for (Rank rank = RANK_8; rank >= RANK_1; --rank)
{
- for (File file = FILE_A; file <= FILE_H; file++)
+ for (File file = FILE_A; file <= FILE_H; ++file)
{
Square sq = file | rank;
- if (is_empty(sq))
+ if (empty(sq))
{
int emptyCnt = 1;
- for ( ; file < FILE_H && is_empty(sq++); file++)
- emptyCnt++;
+ for ( ; file < FILE_H && empty(++sq); ++file)
+ ++emptyCnt;
ss << emptyCnt;
}
/// pieces, according to the call parameters. Pinned pieces protect our king,
/// discovery check pieces attack the enemy king.
-Bitboard Position::hidden_checkers(Square ksq, Color c) const {
+Bitboard Position::hidden_checkers(Square ksq, Color c, Color toMove) const {
Bitboard b, pinners, result = 0;
b = between_bb(ksq, pop_lsb(&pinners)) & pieces();
if (!more_than_one(b))
- result |= b & pieces(sideToMove);
+ result |= b & pieces(toMove);
}
return result;
}
}
-/// Position::attacks_from() computes a bitboard of all attacks of a given piece
-/// put in a given square. Slider attacks use occ bitboard as occupancy.
-
-Bitboard Position::attacks_from(Piece p, Square s, Bitboard occ) {
-
- assert(is_ok(s));
-
- switch (type_of(p))
- {
- 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];
- }
-}
-
-
-/// Position::pl_move_is_legal() tests whether a pseudo-legal move is legal
+/// Position::legal() tests whether a pseudo-legal move is legal
-bool Position::pl_move_is_legal(Move m, Bitboard pinned) const {
+bool Position::legal(Move m, Bitboard pinned) const {
assert(is_ok(m));
- assert(pinned == pinned_pieces());
+ assert(pinned == pinned_pieces(sideToMove));
Color us = sideToMove;
Square from = from_sq(m);
- assert(color_of(piece_moved(m)) == us);
+ assert(color_of(moved_piece(m)) == us);
assert(piece_on(king_square(us)) == make_piece(us, KING));
// En passant captures are a tricky special case. Because they are rather
Bitboard b = (pieces() ^ from ^ capsq) | to;
assert(to == ep_square());
- assert(piece_moved(m) == make_piece(us, PAWN));
+ assert(moved_piece(m) == make_piece(us, PAWN));
assert(piece_on(capsq) == make_piece(them, PAWN));
assert(piece_on(to) == NO_PIECE);
// is moving along the ray towards or away from the king.
return !pinned
|| !(pinned & from)
- || squares_aligned(from, to_sq(m), king_square(us));
+ || aligned(from, to_sq(m), king_square(us));
}
-/// Position::is_pseudo_legal() takes a random move and tests whether the move
-/// is pseudo legal. It is used to validate moves from TT that can be corrupted
+/// Position::pseudo_legal() takes a random move and tests whether the move is
+/// pseudo legal. It is used to validate moves from TT that can be corrupted
/// due to SMP concurrent access or hash position key aliasing.
-bool Position::is_pseudo_legal(const Move m) const {
+bool Position::pseudo_legal(const Move m) const {
Color us = sideToMove;
Square from = from_sq(m);
Square to = to_sq(m);
- Piece pc = piece_moved(m);
+ Piece pc = moved_piece(m);
// Use a slower but simpler function for uncommon cases
if (type_of(m) != NORMAL)
case DELTA_N:
case DELTA_S:
// Pawn push. The destination square must be empty.
- if (!is_empty(to))
+ if (!empty(to))
return false;
break;
// rank, and both the destination square and the square between the
// source and destination squares must be empty.
if ( rank_of(to) != RANK_4
- || !is_empty(to)
- || !is_empty(from + DELTA_N))
+ || !empty(to)
+ || !empty(from + DELTA_N))
return false;
break;
// rank, and both the destination square and the square between the
// source and destination squares must be empty.
if ( rank_of(to) != RANK_5
- || !is_empty(to)
- || !is_empty(from + DELTA_S))
+ || !empty(to)
+ || !empty(from + DELTA_S))
return false;
break;
/// Position::move_gives_check() tests whether a pseudo-legal move gives a check
-bool Position::move_gives_check(Move m, const CheckInfo& ci) const {
+bool Position::gives_check(Move m, const CheckInfo& ci) const {
assert(is_ok(m));
assert(ci.dcCandidates == discovered_check_candidates());
- assert(color_of(piece_moved(m)) == sideToMove);
+ assert(color_of(moved_piece(m)) == sideToMove);
Square from = from_sq(m);
Square to = to_sq(m);
if (ci.checkSq[pt] & to)
return true;
- // Discovery check ?
- if (unlikely(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(~sideToMove)))
- return true;
- }
+ // Discovered check ?
+ if ( unlikely(ci.dcCandidates)
+ && (ci.dcCandidates & from)
+ && !aligned(from, to, king_square(~sideToMove)))
+ return true;
// Can we skip the ugly special cases ?
if (type_of(m) == NORMAL)
switch (type_of(m))
{
case PROMOTION:
- return attacks_from(Piece(promotion_type(m)), to, pieces() ^ from) & ksq;
+ return attacks_bb(Piece(promotion_type(m)), to, pieces() ^ from) & ksq;
// En passant capture with check ? We have already handled the case
// of direct checks and ordinary discovered check, the only case we
void Position::do_move(Move m, StateInfo& newSt) {
CheckInfo ci(*this);
- do_move(m, newSt, ci, move_gives_check(m, ci));
+ do_move(m, newSt, ci, gives_check(m, ci));
}
void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveIsCheck) {
assert(is_ok(m));
assert(&newSt != st);
- nodes++;
+ ++nodes;
Key k = st->key;
// Copy some fields of old state to our new StateInfo object except the ones
// Increment ply counters.In particular rule50 will be later reset it to zero
// in case of a capture or a pawn move.
- gamePly++;
- st->rule50++;
- st->pliesFromNull++;
+ ++gamePly;
+ ++st->rule50;
+ ++st->pliesFromNull;
Color us = sideToMove;
Color them = ~us;
Square to = to_sq(m);
Piece pc = piece_on(from);
PieceType pt = type_of(pc);
- PieceType capture = type_of(m) == ENPASSANT ? PAWN : type_of(piece_on(to));
+ 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) == CASTLE);
- assert(capture != KING);
+ assert(captured != KING);
if (type_of(m) == CASTLE)
{
Square rfrom = to; // Castle is encoded as "king captures friendly rook"
Square rto = relative_square(us, kingSide ? SQ_F1 : SQ_D1);
to = relative_square(us, kingSide ? SQ_G1 : SQ_C1);
- capture = NO_PIECE_TYPE;
+ captured = NO_PIECE_TYPE;
do_castle(from, to, rfrom, rto);
k ^= Zobrist::psq[us][ROOK][rfrom] ^ Zobrist::psq[us][ROOK][rto];
}
- if (capture)
+ if (captured)
{
Square capsq = to;
// If the captured piece is a pawn, update pawn hash key, otherwise
// update non-pawn material.
- if (capture == PAWN)
+ if (captured == PAWN)
{
if (type_of(m) == ENPASSANT)
{
st->pawnKey ^= Zobrist::psq[them][PAWN][capsq];
}
else
- st->npMaterial[them] -= PieceValue[MG][capture];
+ st->npMaterial[them] -= PieceValue[MG][captured];
// Update board and piece lists
- remove_piece(capsq, them, capture);
+ remove_piece(capsq, them, captured);
// Update material hash key and prefetch access to materialTable
- k ^= Zobrist::psq[them][capture][capsq];
- st->materialKey ^= Zobrist::psq[them][capture][pieceCount[them][capture]];
+ k ^= Zobrist::psq[them][captured][capsq];
+ st->materialKey ^= Zobrist::psq[them][captured][pieceCount[them][captured]];
prefetch((char*)thisThread->materialTable[st->materialKey]);
// Update incremental scores
- st->psq -= psq[them][capture][capsq];
+ st->psq -= psq[them][captured][capsq];
// Reset rule 50 counter
st->rule50 = 0;
st->psq += psq[us][pt][to] - psq[us][pt][from];
// Set capture piece
- st->capturedType = capture;
+ st->capturedType = captured;
// Update the key with the final value
st->key = k;
Square from = from_sq(m);
Square to = to_sq(m);
PieceType pt = type_of(piece_on(to));
- PieceType capture = st->capturedType;
+ PieceType captured = st->capturedType;
- assert(is_empty(from) || type_of(m) == CASTLE);
- assert(capture != KING);
+ assert(empty(from) || type_of(m) == CASTLE);
+ assert(captured != KING);
if (type_of(m) == PROMOTION)
{
Square rfrom = to; // Castle is encoded as "king captures friendly rook"
Square rto = relative_square(us, kingSide ? SQ_F1 : SQ_D1);
to = relative_square(us, kingSide ? SQ_G1 : SQ_C1);
- capture = NO_PIECE_TYPE;
+ captured = NO_PIECE_TYPE;
pt = KING;
do_castle(to, from, rto, rfrom);
}
else
move_piece(to, from, us, pt); // Put the piece back at the source square
- if (capture)
+ if (captured)
{
Square capsq = to;
assert(piece_on(capsq) == NO_PIECE);
}
- put_piece(capsq, them, capture); // Restore the captured piece
+ put_piece(capsq, them, captured); // Restore the captured piece
}
// Finally point our state pointer back to the previous state
st = st->previous;
- gamePly--;
+ --gamePly;
assert(pos_is_ok());
}
st->key ^= Zobrist::side;
prefetch((char*)TT.first_entry(st->key));
- st->rule50++;
+ ++st->rule50;
st->pliesFromNull = 0;
sideToMove = ~sideToMove;
// 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 (PieceValue[MG][piece_moved(m)] <= PieceValue[MG][piece_on(to_sq(m))])
+ if (PieceValue[MG][moved_piece(m)] <= PieceValue[MG][piece_on(to_sq(m))])
return 1;
return see(m);
from = from_sq(m);
to = to_sq(m);
- swapList[0] = PieceValue[MG][type_of(piece_on(to))];
+ swapList[0] = PieceValue[MG][piece_on(to)];
stm = color_of(piece_on(from));
occupied = pieces() ^ from;
// Add the new entry to the swap list
swapList[slIndex] = -swapList[slIndex - 1] + PieceValue[MG][captured];
- slIndex++;
+ ++slIndex;
// Locate and remove the next least valuable attacker
captured = min_attacker<PAWN>(byTypeBB, to, stmAttackers, occupied, attackers);
// 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.
while (--slIndex)
- swapList[slIndex-1] = std::min(-swapList[slIndex], swapList[slIndex-1]);
+ swapList[slIndex - 1] = std::min(-swapList[slIndex], swapList[slIndex - 1]);
return swapList[0];
}
startState.epSquare = SQ_NONE;
st = &startState;
- 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 (int i = 0; i < PIECE_TYPE_NB; ++i)
+ for (int j = 0; j < 16; ++j)
+ pieceList[WHITE][i][j] = pieceList[BLACK][i][j] = SQ_NONE;
}
Key k = 0;
- for (Color c = WHITE; c <= BLACK; c++)
- for (PieceType pt = PAWN; pt <= QUEEN; pt++)
- for (int cnt = 0; cnt < pieceCount[c][pt]; cnt++)
+ for (Color c = WHITE; c <= BLACK; ++c)
+ for (PieceType pt = PAWN; pt <= QUEEN; ++pt)
+ for (int cnt = 0; cnt < pieceCount[c][pt]; ++cnt)
k ^= Zobrist::psq[c][pt][cnt];
return k;
/// game and the endgame. These functions are used to initialize the incremental
/// scores when a new position is set up, and to verify that the scores are correctly
/// updated by do_move and undo_move when the program is running in debug mode.
+
Score Position::compute_psq_score() const {
Score score = SCORE_ZERO;
Value value = VALUE_ZERO;
- for (PieceType pt = KNIGHT; pt <= QUEEN; pt++)
+ for (PieceType pt = KNIGHT; pt <= QUEEN; ++pt)
value += pieceCount[c][pt] * PieceValue[MG][pt];
return value;
if (st->rule50 > 99 && (!checkers() || MoveList<LEGAL>(*this).size()))
return true;
- // Draw by repetition?
int i = 4, e = std::min(st->rule50, st->pliesFromNull);
if (i <= e)
stp = stp->previous->previous;
if (stp->key == st->key)
- return true;
+ return true; // Draw after first repetition
i += 2;
/// Position::flip() flips position with the white and black sides reversed. This
/// is only useful for debugging especially for finding evaluation symmetry bugs.
+static char toggle_case(char c) {
+ return char(islower(c) ? toupper(c) : tolower(c));
+}
+
void Position::flip() {
- const Position pos(*this);
+ string f, token;
+ std::stringstream ss(fen());
- clear();
+ for (Rank rank = RANK_8; rank >= RANK_1; --rank) // Piece placement
+ {
+ std::getline(ss, token, rank > RANK_1 ? '/' : ' ');
+ f.insert(0, token + (f.empty() ? " " : "/"));
+ }
- sideToMove = ~pos.side_to_move();
- thisThread = pos.this_thread();
- nodes = pos.nodes_searched();
- chess960 = pos.is_chess960();
- gamePly = pos.game_ply();
+ ss >> token; // Active color
+ f += (token == "w" ? "B " : "W "); // Will be lowercased later
- for (Square s = SQ_A1; s <= SQ_H8; s++)
- if (!pos.is_empty(s))
- {
- Piece p = Piece(pos.piece_on(s) ^ 8);
- put_piece(~s, color_of(p), type_of(p));
- }
+ ss >> token; // Castling availability
+ f += token + " ";
- if (pos.can_castle(WHITE_OO))
- set_castle_right(BLACK, ~pos.castle_rook_square(WHITE, KING_SIDE));
- if (pos.can_castle(WHITE_OOO))
- set_castle_right(BLACK, ~pos.castle_rook_square(WHITE, QUEEN_SIDE));
- if (pos.can_castle(BLACK_OO))
- set_castle_right(WHITE, ~pos.castle_rook_square(BLACK, KING_SIDE));
- if (pos.can_castle(BLACK_OOO))
- set_castle_right(WHITE, ~pos.castle_rook_square(BLACK, QUEEN_SIDE));
+ std::transform(f.begin(), f.end(), f.begin(), toggle_case);
- if (pos.st->epSquare != SQ_NONE)
- st->epSquare = ~pos.st->epSquare;
+ ss >> token; // En passant square
+ f += (token == "-" ? token : token.replace(1, 1, token[1] == '3' ? "6" : "3"));
- st->checkersBB = attackers_to(king_square(sideToMove)) & pieces(~sideToMove);
+ std::getline(ss, token); // Half and full moves
+ f += token;
- st->key = compute_key();
- st->pawnKey = compute_pawn_key();
- st->materialKey = compute_material_key();
- st->psq = compute_psq_score();
- st->npMaterial[WHITE] = compute_non_pawn_material(WHITE);
- st->npMaterial[BLACK] = compute_non_pawn_material(BLACK);
+ set(f, is_chess960(), this_thread());
assert(pos_is_ok());
}
{
int kingCount[COLOR_NB] = {};
- for (Square s = SQ_A1; s <= SQ_H8; s++)
+ for (Square s = SQ_A1; s <= SQ_H8; ++s)
if (type_of(piece_on(s)) == KING)
- kingCount[color_of(piece_on(s))]++;
+ ++kingCount[color_of(piece_on(s))];
if (kingCount[0] != 1 || kingCount[1] != 1)
return false;
return false;
// Separate piece type bitboards must have empty intersections
- for (PieceType p1 = PAWN; p1 <= KING; p1++)
- for (PieceType p2 = PAWN; p2 <= KING; p2++)
+ for (PieceType p1 = PAWN; p1 <= KING; ++p1)
+ for (PieceType p2 = PAWN; p2 <= KING; ++p2)
if (p1 != p2 && (pieces(p1) & pieces(p2)))
return false;
}
return false;
if ((*step)++, debugPieceCounts)
- for (Color c = WHITE; c <= BLACK; c++)
- for (PieceType pt = PAWN; pt <= KING; pt++)
+ for (Color c = WHITE; c <= BLACK; ++c)
+ for (PieceType pt = PAWN; pt <= KING; ++pt)
if (pieceCount[c][pt] != popcount<Full>(pieces(c, pt)))
return false;
if ((*step)++, debugPieceList)
- for (Color c = WHITE; c <= BLACK; c++)
- for (PieceType pt = PAWN; pt <= KING; pt++)
- for (int i = 0; i < pieceCount[c][pt]; i++)
+ 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)
return false;
if ((*step)++, debugCastleSquares)
- for (Color c = WHITE; c <= BLACK; c++)
+ for (Color c = WHITE; c <= BLACK; ++c)
for (CastlingSide s = KING_SIDE; s <= QUEEN_SIDE; s = CastlingSide(s + 1))
{
CastleRight cr = make_castle_right(c, s);
projects / stockfish / blobdiff