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DroidFish: Updated stockfish to version 231015.

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This commit is contained in:
Peter Osterlund
2015-10-23 22:58:14 +02:00
parent e768c9408a
commit 0d72a21f27
39 changed files with 2118 additions and 2574 deletions
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366
DroidFish/jni/stockfish/position.cpp
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@@ -19,7 +19,7 @@
#include <algorithm>
#include <cassert>
#include <cstring> // For std::memset
#include <cstring> // For std::memset, std::memcmp
#include <iomanip>
#include <sstream>
@@ -27,7 +27,6 @@
#include "misc.h"
#include "movegen.h"
#include "position.h"
#include "psqtab.h"
#include "thread.h"
#include "tt.h"
#include "uci.h"
@@ -47,19 +46,18 @@ namespace Zobrist {
Key exclusion;
}
Key Position::exclusion_key() const { return st->key ^ Zobrist::exclusion;}
Key Position::exclusion_key() const { return st->key ^ Zobrist::exclusion; }
namespace {
const string PieceToChar(" PNBRQK pnbrqk");
Score psq[COLOR_NB][PIECE_TYPE_NB][SQUARE_NB];
// min_attacker() is a helper function used by see() to locate the least
// valuable attacker for the side to move, remove the attacker we just found
// from the bitboards and scan for new X-ray attacks behind it.
template<int Pt> FORCE_INLINE
PieceType min_attacker(const Bitboard* bb, const Square& to, const Bitboard& stmAttackers,
template<int Pt>
PieceType min_attacker(const Bitboard* bb, Square to, Bitboard stmAttackers,
Bitboard& occupied, Bitboard& attackers) {
Bitboard b = stmAttackers & bb[Pt];
@@ -78,8 +76,8 @@ PieceType min_attacker(const Bitboard* bb, const Square& to, const Bitboard& stm
return (PieceType)Pt;
}
template<> FORCE_INLINE
PieceType min_attacker<KING>(const Bitboard*, const Square&, const Bitboard&, Bitboard&, Bitboard&) {
template<>
PieceType min_attacker<KING>(const Bitboard*, Square, Bitboard, Bitboard&, Bitboard&) {
return KING; // No need to update bitboards: it is the last cycle
}
@@ -91,17 +89,17 @@ PieceType min_attacker<KING>(const Bitboard*, const Square&, const Bitboard&, Bi
CheckInfo::CheckInfo(const Position& pos) {
Color them = ~pos.side_to_move();
ksq = pos.king_square(them);
ksq = pos.square<KING>(them);
pinned = pos.pinned_pieces(pos.side_to_move());
dcCandidates = pos.discovered_check_candidates();
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] = 0;
checkSquares[PAWN] = pos.attacks_from<PAWN>(ksq, them);
checkSquares[KNIGHT] = pos.attacks_from<KNIGHT>(ksq);
checkSquares[BISHOP] = pos.attacks_from<BISHOP>(ksq);
checkSquares[ROOK] = pos.attacks_from<ROOK>(ksq);
checkSquares[QUEEN] = checkSquares[BISHOP] | checkSquares[ROOK];
checkSquares[KING] = 0;
}
@@ -130,10 +128,7 @@ std::ostream& operator<<(std::ostream& os, const Position& pos) {
/// Position::init() initializes at startup the various arrays used to compute
/// hash keys and the piece square tables. The latter is a two-step operation:
/// Firstly, the white halves of the tables are copied from PSQT[] tables.
/// Secondly, the black halves of the tables are initialized by flipping and
/// changing the sign of the white scores.
/// hash keys.
void Position::init() {
@@ -149,6 +144,7 @@ void Position::init() {
for (int cr = NO_CASTLING; cr <= ANY_CASTLING; ++cr)
{
Zobrist::castling[cr] = 0;
Bitboard b = cr;
while (b)
{
@@ -159,20 +155,6 @@ void Position::init() {
Zobrist::side = rng.rand<Key>();
Zobrist::exclusion = rng.rand<Key>();
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)
{
psq[WHITE][pt][ s] = (v + PSQT[pt][s]);
psq[BLACK][pt][~s] = -(v + PSQT[pt][s]);
}
}
}
@@ -182,7 +164,7 @@ void Position::init() {
Position& Position::operator=(const Position& pos) {
std::memcpy(this, &pos, sizeof(Position));
startState = *st;
std::memcpy(&startState, st, sizeof(StateInfo));
st = &startState;
nodes = 0;
@@ -265,7 +247,7 @@ void Position::set(const string& fenStr, bool isChess960, Thread* th) {
else if ((idx = PieceToChar.find(token)) != string::npos)
{
put_piece(sq, color_of(Piece(idx)), type_of(Piece(idx)));
put_piece(color_of(Piece(idx)), type_of(Piece(idx)), sq);
++sq;
}
}
@@ -284,14 +266,15 @@ void Position::set(const string& fenStr, bool isChess960, Thread* th) {
{
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); type_of(piece_on(rsq)) != ROOK; --rsq) {}
for (rsq = relative_square(c, SQ_H1); 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); piece_on(rsq) != rook; ++rsq) {}
else if (token >= 'A' && token <= 'H')
rsq = make_square(File(token - 'A'), relative_rank(c, RANK_1));
@@ -332,7 +315,7 @@ void Position::set(const string& fenStr, bool isChess960, Thread* th) {
void Position::set_castling_right(Color c, Square rfrom) {
Square kfrom = king_square(c);
Square kfrom = square<KING>(c);
CastlingSide cs = kfrom < rfrom ? KING_SIDE : QUEEN_SIDE;
CastlingRight cr = (c | cs);
@@ -365,23 +348,23 @@ void Position::set_state(StateInfo* si) const {
si->nonPawnMaterial[WHITE] = si->nonPawnMaterial[BLACK] = VALUE_ZERO;
si->psq = SCORE_ZERO;
si->checkersBB = attackers_to(king_square(sideToMove)) & pieces(~sideToMove);
si->checkersBB = attackers_to(square<KING>(sideToMove)) & pieces(~sideToMove);
for (Bitboard b = pieces(); b; )
{
Square s = pop_lsb(&b);
Piece pc = piece_on(s);
si->key ^= Zobrist::psq[color_of(pc)][type_of(pc)][s];
si->psq += psq[color_of(pc)][type_of(pc)][s];
si->psq += PSQT::psq[color_of(pc)][type_of(pc)][s];
}
if (ep_square() != SQ_NONE)
si->key ^= Zobrist::enpassant[file_of(ep_square())];
if (si->epSquare != SQ_NONE)
si->key ^= Zobrist::enpassant[file_of(si->epSquare)];
if (sideToMove == BLACK)
si->key ^= Zobrist::side;
si->key ^= Zobrist::castling[st->castlingRights];
si->key ^= Zobrist::castling[si->castlingRights];
for (Bitboard b = pieces(PAWN); b; )
{
@@ -473,7 +456,7 @@ Phase Position::game_phase() const {
Bitboard Position::check_blockers(Color c, Color kingColor) const {
Bitboard b, pinners, result = 0;
Square ksq = king_square(kingColor);
Square ksq = square<KING>(kingColor);
// Pinners are sliders that give check when a pinned piece is removed
pinners = ( (pieces( ROOK, QUEEN) & PseudoAttacks[ROOK ][ksq])
@@ -498,7 +481,7 @@ Bitboard Position::attackers_to(Square s, Bitboard occupied) const {
return (attacks_from<PAWN>(s, BLACK) & pieces(WHITE, PAWN))
| (attacks_from<PAWN>(s, WHITE) & pieces(BLACK, PAWN))
| (attacks_from<KNIGHT>(s) & pieces(KNIGHT))
| (attacks_bb<ROOK>(s, occupied) & pieces(ROOK, QUEEN))
| (attacks_bb<ROOK >(s, occupied) & pieces(ROOK, QUEEN))
| (attacks_bb<BISHOP>(s, occupied) & pieces(BISHOP, QUEEN))
| (attacks_from<KING>(s) & pieces(KING));
}
@@ -515,14 +498,14 @@ bool Position::legal(Move m, Bitboard pinned) const {
Square from = from_sq(m);
assert(color_of(moved_piece(m)) == us);
assert(piece_on(king_square(us)) == make_piece(us, KING));
assert(piece_on(square<KING>(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 (type_of(m) == ENPASSANT)
{
Square ksq = king_square(us);
Square ksq = square<KING>(us);
Square to = to_sq(m);
Square capsq = to - pawn_push(us);
Bitboard occupied = (pieces() ^ from ^ capsq) | to;
@@ -546,7 +529,7 @@ bool Position::legal(Move m, Bitboard pinned) const {
// is moving along the ray towards or away from the king.
return !pinned
|| !(pinned & from)
|| aligned(from, to_sq(m), king_square(us));
|| aligned(from, to_sq(m), square<KING>(us));
}
@@ -566,7 +549,7 @@ bool Position::pseudo_legal(const Move m) const {
return MoveList<LEGAL>(*this).contains(m);
// Is not a promotion, so promotion piece must be empty
if (promotion_type(m) - 2 != NO_PIECE_TYPE)
if (promotion_type(m) - KNIGHT != NO_PIECE_TYPE)
return false;
// If the 'from' square is not occupied by a piece belonging to the side to
@@ -587,9 +570,7 @@ bool Position::pseudo_legal(const Move m) const {
return false;
if ( !(attacks_from<PAWN>(from, us) & pieces(~us) & to) // Not a capture
&& !((from + pawn_push(us) == to) && empty(to)) // Not a single push
&& !( (from + 2 * pawn_push(us) == to) // Not a double push
&& (rank_of(from) == relative_rank(us, RANK_2))
&& empty(to)
@@ -611,7 +592,7 @@ bool Position::pseudo_legal(const Move m) const {
return false;
// Our move must be a blocking evasion or a capture of the checking piece
if (!((between_bb(lsb(checkers()), king_square(us)) | checkers()) & to))
if (!((between_bb(lsb(checkers()), square<KING>(us)) | checkers()) & to))
return false;
}
// In case of king moves under check we have to remove king so as to catch
@@ -634,10 +615,9 @@ bool Position::gives_check(Move m, const CheckInfo& ci) const {
Square from = from_sq(m);
Square to = to_sq(m);
PieceType pt = type_of(piece_on(from));
// Is there a direct check?
if (ci.checkSq[pt] & to)
if (ci.checkSquares[type_of(piece_on(from))] & to)
return true;
// Is there a discovered check?
@@ -687,31 +667,21 @@ bool Position::gives_check(Move m, const CheckInfo& ci) const {
/// 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, gives_check(m, ci));
}
void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveIsCheck) {
void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) {
assert(is_ok(m));
assert(&newSt != st);
++nodes;
Key k = st->key;
Key k = st->key ^ Zobrist::side;
// Copy some fields of the old state to our new StateInfo object except the
// ones which are going to be recalculated from scratch anyway and then switch
// our state pointer to point to the new (ready to be updated) state.
std::memcpy(&newSt, st, StateCopySize64 * sizeof(uint64_t));
std::memcpy(&newSt, st, offsetof(StateInfo, key));
newSt.previous = st;
st = &newSt;
// Update side to move
k ^= Zobrist::side;
// Increment ply counters. In particular, rule50 will be reset to zero later on
// in case of a capture or a pawn move.
++gamePly;
@@ -722,23 +692,22 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
Color them = ~us;
Square from = from_sq(m);
Square to = to_sq(m);
Piece pc = piece_on(from);
PieceType pt = type_of(pc);
PieceType pt = type_of(piece_on(from));
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) == CASTLING);
assert(color_of(piece_on(from)) == us);
assert(piece_on(to) == NO_PIECE || color_of(piece_on(to)) == (type_of(m) != CASTLING ? them : us));
assert(captured != KING);
if (type_of(m) == CASTLING)
{
assert(pc == make_piece(us, KING));
assert(pt == KING);
Square rfrom, rto;
do_castling<true>(from, to, rfrom, rto);
do_castling<true>(us, from, to, rfrom, rto);
captured = NO_PIECE_TYPE;
st->psq += psq[us][ROOK][rto] - psq[us][ROOK][rfrom];
st->psq += PSQT::psq[us][ROOK][rto] - PSQT::psq[us][ROOK][rfrom];
k ^= Zobrist::psq[us][ROOK][rfrom] ^ Zobrist::psq[us][ROOK][rto];
}
@@ -752,7 +721,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
{
if (type_of(m) == ENPASSANT)
{
capsq += pawn_push(them);
capsq -= pawn_push(us);
assert(pt == PAWN);
assert(to == st->epSquare);
@@ -760,7 +729,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
assert(piece_on(to) == NO_PIECE);
assert(piece_on(capsq) == make_piece(them, PAWN));
board[capsq] = NO_PIECE;
board[capsq] = NO_PIECE; // Not done by remove_piece()
}
st->pawnKey ^= Zobrist::psq[them][PAWN][capsq];
@@ -769,15 +738,15 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
st->nonPawnMaterial[them] -= PieceValue[MG][captured];
// Update board and piece lists
remove_piece(capsq, them, captured);
remove_piece(them, captured, capsq);
// Update material hash key and prefetch access to materialTable
k ^= Zobrist::psq[them][captured][capsq];
st->materialKey ^= Zobrist::psq[them][captured][pieceCount[them][captured]];
prefetch((char*)thisThread->materialTable[st->materialKey]);
prefetch(thisThread->materialTable[st->materialKey]);
// Update incremental scores
st->psq -= psq[them][captured][capsq];
st->psq -= PSQT::psq[them][captured][capsq];
// Reset rule 50 counter
st->rule50 = 0;
@@ -803,16 +772,16 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
// Move the piece. The tricky Chess960 castling is handled earlier
if (type_of(m) != CASTLING)
move_piece(from, to, us, pt);
move_piece(us, pt, from, to);
// If the moving piece is a pawn do some special extra work
if (pt == PAWN)
{
// Set en-passant square if the moved pawn can be captured
if ( (int(to) ^ int(from)) == 16
&& (attacks_from<PAWN>(from + pawn_push(us), us) & pieces(them, PAWN)))
&& (attacks_from<PAWN>(to - pawn_push(us), us) & pieces(them, PAWN)))
{
st->epSquare = Square((from + to) / 2);
st->epSquare = (from + to) / 2;
k ^= Zobrist::enpassant[file_of(st->epSquare)];
}
@@ -823,8 +792,8 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
assert(relative_rank(us, to) == RANK_8);
assert(promotion >= KNIGHT && promotion <= QUEEN);
remove_piece(to, us, PAWN);
put_piece(to, us, promotion);
remove_piece(us, PAWN, to);
put_piece(us, promotion, to);
// Update hash keys
k ^= Zobrist::psq[us][PAWN][to] ^ Zobrist::psq[us][promotion][to];
@@ -833,7 +802,7 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
^ Zobrist::psq[us][PAWN][pieceCount[us][PAWN]];
// Update incremental score
st->psq += psq[us][promotion][to] - psq[us][PAWN][to];
st->psq += PSQT::psq[us][promotion][to] - PSQT::psq[us][PAWN][to];
// Update material
st->nonPawnMaterial[us] += PieceValue[MG][promotion];
@@ -841,14 +810,14 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
// Update pawn hash key and prefetch access to pawnsTable
st->pawnKey ^= Zobrist::psq[us][PAWN][from] ^ Zobrist::psq[us][PAWN][to];
prefetch((char*)thisThread->pawnsTable[st->pawnKey]);
prefetch(thisThread->pawnsTable[st->pawnKey]);
// Reset rule 50 draw counter
st->rule50 = 0;
}
// Update incremental scores
st->psq += psq[us][pt][to] - psq[us][pt][from];
st->psq += PSQT::psq[us][pt][to] - PSQT::psq[us][pt][from];
// Set capture piece
st->capturedType = captured;
@@ -856,30 +825,8 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
// Update the key with the final value
st->key = k;
// Update checkers bitboard: piece must be already moved due to attacks_from()
st->checkersBB = 0;
if (moveIsCheck)
{
if (type_of(m) != NORMAL)
st->checkersBB = attackers_to(king_square(them)) & pieces(us);
else
{
// Direct checks
if (ci.checkSq[pt] & to)
st->checkersBB |= to;
// Discovered checks
if (ci.dcCandidates && (ci.dcCandidates & from))
{
if (pt != ROOK)
st->checkersBB |= attacks_from<ROOK>(king_square(them)) & pieces(us, QUEEN, ROOK);
if (pt != BISHOP)
st->checkersBB |= attacks_from<BISHOP>(king_square(them)) & pieces(us, QUEEN, BISHOP);
}
}
}
// Calculate checkers bitboard (if move gives check)
st->checkersBB = givesCheck ? attackers_to(square<KING>(them)) & pieces(us) : 0;
sideToMove = ~sideToMove;
@@ -906,23 +853,23 @@ void Position::undo_move(Move m) {
if (type_of(m) == PROMOTION)
{
assert(pt == promotion_type(m));
assert(relative_rank(us, to) == RANK_8);
assert(promotion_type(m) >= KNIGHT && promotion_type(m) <= QUEEN);
assert(pt == promotion_type(m));
assert(pt >= KNIGHT && pt <= QUEEN);
remove_piece(to, us, promotion_type(m));
put_piece(to, us, PAWN);
remove_piece(us, pt, to);
put_piece(us, PAWN, to);
pt = PAWN;
}
if (type_of(m) == CASTLING)
{
Square rfrom, rto;
do_castling<false>(from, to, rfrom, rto);
do_castling<false>(us, from, to, rfrom, rto);
}
else
{
move_piece(to, from, us, pt); // Put the piece back at the source square
move_piece(us, pt, to, from); // Put the piece back at the source square
if (st->capturedType)
{
@@ -936,9 +883,10 @@ void Position::undo_move(Move m) {
assert(to == st->previous->epSquare);
assert(relative_rank(us, to) == RANK_6);
assert(piece_on(capsq) == NO_PIECE);
assert(st->capturedType == PAWN);
}
put_piece(capsq, ~us, st->capturedType); // Restore the captured piece
put_piece(~us, st->capturedType, capsq); // Restore the captured piece
}
}
@@ -953,19 +901,19 @@ void Position::undo_move(Move m) {
/// Position::do_castling() is a helper used to do/undo a castling move. This
/// is a bit tricky, especially in Chess960.
template<bool Do>
void Position::do_castling(Square from, Square& to, Square& rfrom, Square& rto) {
void Position::do_castling(Color us, Square from, Square& to, Square& rfrom, Square& rto) {
bool kingSide = to > from;
rfrom = to; // Castling is encoded as "king captures friendly rook"
rto = relative_square(sideToMove, kingSide ? SQ_F1 : SQ_D1);
to = relative_square(sideToMove, kingSide ? SQ_G1 : SQ_C1);
rto = relative_square(us, kingSide ? SQ_F1 : SQ_D1);
to = relative_square(us, kingSide ? SQ_G1 : SQ_C1);
// Remove both pieces first since squares could overlap in Chess960
remove_piece(Do ? from : to, sideToMove, KING);
remove_piece(Do ? rfrom : rto, sideToMove, ROOK);
remove_piece(us, KING, Do ? from : to);
remove_piece(us, ROOK, Do ? rfrom : rto);
board[Do ? from : to] = board[Do ? rfrom : rto] = NO_PIECE; // Since remove_piece doesn't do it for us
put_piece(Do ? to : from, sideToMove, KING);
put_piece(Do ? rto : rfrom, sideToMove, ROOK);
put_piece(us, KING, Do ? to : from);
put_piece(us, ROOK, Do ? rto : rfrom);
}
@@ -975,9 +923,9 @@ void Position::do_castling(Square from, Square& to, Square& rfrom, Square& rto)
void Position::do_null_move(StateInfo& newSt) {
assert(!checkers());
assert(&newSt != st);
std::memcpy(&newSt, st, sizeof(StateInfo)); // Fully copy here
std::memcpy(&newSt, st, sizeof(StateInfo));
newSt.previous = st;
st = &newSt;
@@ -988,7 +936,7 @@ void Position::do_null_move(StateInfo& newSt) {
}
st->key ^= Zobrist::side;
prefetch((char*)TT.first_entry(st->key));
prefetch(TT.first_entry(st->key));
++st->rule50;
st->pliesFromNull = 0;
@@ -1060,8 +1008,8 @@ Value Position::see(Move m) const {
stm = color_of(piece_on(from));
occupied = pieces() ^ from;
// Castling moves are implemented as king capturing the rook so cannot be
// handled correctly. Simply return 0 that is always the correct value
// Castling moves are implemented as king capturing the rook so cannot
// be handled correctly. Simply return VALUE_ZERO that is always correct
// unless in the rare case the rook ends up under attack.
if (type_of(m) == CASTLING)
return VALUE_ZERO;
@@ -1098,21 +1046,11 @@ Value Position::see(Move m) const {
// Locate and remove the next least valuable attacker
captured = min_attacker<PAWN>(byTypeBB, to, stmAttackers, occupied, attackers);
// Stop before processing a king capture
if (captured == KING)
{
if (stmAttackers == attackers)
++slIndex;
break;
}
stm = ~stm;
stmAttackers = attackers & pieces(stm);
++slIndex;
} while (stmAttackers);
} while (stmAttackers && (captured != KING || (--slIndex, false))); // Stop before a king capture
// 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.
@@ -1123,8 +1061,8 @@ Value Position::see(Move m) const {
}
/// Position::is_draw() tests whether the position is drawn by material, 50 moves
/// rule or repetition. It does not detect stalemates.
/// Position::is_draw() tests whether the position is drawn by 50-move rule
/// or by repetition. It does not detect stalemates.
bool Position::is_draw() const {
@@ -1147,10 +1085,6 @@ bool Position::is_draw() const {
/// Position::flip() flips position with the white and black sides reversed. This
/// is only useful for debugging e.g. for finding evaluation symmetry bugs.
static char toggle_case(char c) {
return char(islower(c) ? toupper(c) : tolower(c));
}
void Position::flip() {
string f, token;
@@ -1168,7 +1102,8 @@ void Position::flip() {
ss >> token; // Castling availability
f += token + " ";
std::transform(f.begin(), f.end(), f.begin(), toggle_case);
std::transform(f.begin(), f.end(), f.begin(),
[](char c) { return char(islower(c) ? toupper(c) : tolower(c)); });
ss >> token; // En passant square
f += (token == "-" ? token : token.replace(1, 1, token[1] == '3' ? "6" : "3"));
@@ -1185,96 +1120,77 @@ void Position::flip() {
/// Position::pos_is_ok() performs some consistency checks for the position object.
/// This is meant to be helpful when debugging.
bool Position::pos_is_ok(int* step) const {
bool Position::pos_is_ok(int* failedStep) const {
// Which parts of the position should be verified?
const bool all = false;
const bool Fast = true; // Quick (default) or full check?
const bool testBitboards = all || false;
const bool testState = all || false;
const bool testKingCount = all || false;
const bool testKingCapture = all || false;
const bool testPieceCounts = all || false;
const bool testPieceList = all || false;
const bool testCastlingSquares = all || false;
enum { Default, King, Bitboards, State, Lists, Castling };
if (step)
*step = 1;
if ( (sideToMove != WHITE && sideToMove != BLACK)
|| piece_on(king_square(WHITE)) != W_KING
|| piece_on(king_square(BLACK)) != B_KING
|| ( ep_square() != SQ_NONE
&& relative_rank(sideToMove, ep_square()) != RANK_6))
return false;
if (step && ++*step, testBitboards)
for (int step = Default; step <= (Fast ? Default : Castling); step++)
{
// The intersection of the white and black pieces must be empty
if (pieces(WHITE) & pieces(BLACK))
return false;
if (failedStep)
*failedStep = step;
// The union of the white and black pieces must be equal to all
// occupied squares
if ((pieces(WHITE) | pieces(BLACK)) != pieces())
return false;
if (step == Default)
if ( (sideToMove != WHITE && sideToMove != BLACK)
|| piece_on(square<KING>(WHITE)) != W_KING
|| piece_on(square<KING>(BLACK)) != B_KING
|| ( ep_square() != SQ_NONE
&& relative_rank(sideToMove, ep_square()) != RANK_6))
return false;
// Separate piece type bitboards must have empty intersections
for (PieceType p1 = PAWN; p1 <= KING; ++p1)
for (PieceType p2 = PAWN; p2 <= KING; ++p2)
if (p1 != p2 && (pieces(p1) & pieces(p2)))
return false;
}
if (step == King)
if ( std::count(board, board + SQUARE_NB, W_KING) != 1
|| std::count(board, board + SQUARE_NB, B_KING) != 1
|| attackers_to(square<KING>(~sideToMove)) & pieces(sideToMove))
return false;
if (step && ++*step, testState)
{
StateInfo si;
set_state(&si);
if ( st->key != si.key
|| st->pawnKey != si.pawnKey
|| st->materialKey != si.materialKey
|| st->nonPawnMaterial[WHITE] != si.nonPawnMaterial[WHITE]
|| st->nonPawnMaterial[BLACK] != si.nonPawnMaterial[BLACK]
|| st->psq != si.psq
|| st->checkersBB != si.checkersBB)
return false;
}
if (step == Bitboards)
{
if ( (pieces(WHITE) & pieces(BLACK))
||(pieces(WHITE) | pieces(BLACK)) != pieces())
return false;
if (step && ++*step, testKingCount)
if ( std::count(board, board + SQUARE_NB, W_KING) != 1
|| std::count(board, board + SQUARE_NB, B_KING) != 1)
return false;
for (PieceType p1 = PAWN; p1 <= KING; ++p1)
for (PieceType p2 = PAWN; p2 <= KING; ++p2)
if (p1 != p2 && (pieces(p1) & pieces(p2)))
return false;
}
if (step && ++*step, testKingCapture)
if (attackers_to(king_square(~sideToMove)) & pieces(sideToMove))
return false;
if (step == State)
{
StateInfo si = *st;
set_state(&si);
if (std::memcmp(&si, st, sizeof(StateInfo)))
return false;
}
if (step && ++*step, testPieceCounts)
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 && ++*step, testPieceList)
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)
if (step == Lists)
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 && ++*step, testCastlingSquares)
for (Color c = WHITE; c <= BLACK; ++c)
for (CastlingSide s = KING_SIDE; s <= QUEEN_SIDE; s = CastlingSide(s + 1))
{
if (!can_castle(c | s))
continue;
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 ( (castlingRightsMask[king_square(c)] & (c | s)) != (c | s)
|| piece_on(castlingRookSquare[c | s]) != make_piece(c, ROOK)
|| castlingRightsMask[castlingRookSquare[c | s]] != (c | s))
return false;
}
if (step == Castling)
for (Color c = WHITE; c <= BLACK; ++c)
for (CastlingSide s = KING_SIDE; s <= QUEEN_SIDE; s = CastlingSide(s + 1))
{
if (!can_castle(c | s))
continue;
if ( piece_on(castlingRookSquare[c | s]) != make_piece(c, ROOK)
|| castlingRightsMask[castlingRookSquare[c | s]] != (c | s)
||(castlingRightsMask[square<KING>(c)] & (c | s)) != (c | s))
return false;
}
}
return true;
}