droidfish/DroidFish/jni/rtb/moveGen.cpp

345 lines
13 KiB
C++

/*
Texel - A UCI chess engine.
Copyright (C) 2012-2014 Peter Österlund, peterosterlund2@gmail.com
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* moveGen.cpp
*
* Created on: Feb 25, 2012
* Author: petero
*/
#include "moveGen.hpp"
template void MoveGen::pseudoLegalMoves<true>(const Position& pos, MoveList& moveList);
template void MoveGen::pseudoLegalMoves<false>(const Position& pos, MoveList& moveList);
template <bool wtm>
void
MoveGen::pseudoLegalMoves(const Position& pos, MoveList& moveList) {
typedef ColorTraits<wtm> MyColor;
const U64 occupied = pos.occupiedBB();
// Queen moves
U64 squares = pos.pieceTypeBB(MyColor::QUEEN);
while (squares != 0) {
int sq = BitBoard::numberOfTrailingZeros(squares);
U64 m = (BitBoard::rookAttacks(sq, occupied) | BitBoard::bishopAttacks(sq, occupied)) & ~pos.colorBB(wtm);
addMovesByMask(moveList, sq, m);
squares &= squares-1;
}
// Rook moves
squares = pos.pieceTypeBB(MyColor::ROOK);
while (squares != 0) {
int sq = BitBoard::numberOfTrailingZeros(squares);
U64 m = BitBoard::rookAttacks(sq, occupied) & ~pos.colorBB(wtm);
addMovesByMask(moveList, sq, m);
squares &= squares-1;
}
// Bishop moves
squares = pos.pieceTypeBB(MyColor::BISHOP);
while (squares != 0) {
int sq = BitBoard::numberOfTrailingZeros(squares);
U64 m = BitBoard::bishopAttacks(sq, occupied) & ~pos.colorBB(wtm);
addMovesByMask(moveList, sq, m);
squares &= squares-1;
}
// King moves
{
int sq = pos.getKingSq(wtm);
U64 m = BitBoard::kingAttacks[sq] & ~pos.colorBB(wtm);
addMovesByMask(moveList, sq, m);
const int k0 = wtm ? 4 : 60;
if (sq == k0) {
const U64 OO_SQ = wtm ? 0x60ULL : 0x6000000000000000ULL;
const U64 OOO_SQ = wtm ? 0xEULL : 0xE00000000000000ULL;
const int hCastle = wtm ? Position::H1_CASTLE : Position::H8_CASTLE;
const int aCastle = wtm ? Position::A1_CASTLE : Position::A8_CASTLE;
if (((pos.getCastleMask() & (1 << hCastle)) != 0) &&
((OO_SQ & occupied) == 0) &&
(pos.getPiece(k0 + 3) == MyColor::ROOK) &&
!sqAttacked(pos, k0) &&
!sqAttacked(pos, k0 + 1)) {
moveList.addMove(k0, k0 + 2, Piece::EMPTY);
}
if (((pos.getCastleMask() & (1 << aCastle)) != 0) &&
((OOO_SQ & occupied) == 0) &&
(pos.getPiece(k0 - 4) == MyColor::ROOK) &&
!sqAttacked(pos, k0) &&
!sqAttacked(pos, k0 - 1)) {
moveList.addMove(k0, k0 - 2, Piece::EMPTY);
}
}
}
// Knight moves
U64 knights = pos.pieceTypeBB(MyColor::KNIGHT);
while (knights != 0) {
int sq = BitBoard::numberOfTrailingZeros(knights);
U64 m = BitBoard::knightAttacks[sq] & ~pos.colorBB(wtm);
addMovesByMask(moveList, sq, m);
knights &= knights-1;
}
// Pawn moves
const U64 pawns = pos.pieceTypeBB(MyColor::PAWN);
const int epSquare = pos.getEpSquare();
const U64 epMask = (epSquare >= 0) ? (1ULL << epSquare) : 0ULL;
if (wtm) {
U64 m = (pawns << 8) & ~occupied;
addPawnMovesByMask<wtm>(moveList, m, -8, true);
m = ((m & BitBoard::maskRow3) << 8) & ~occupied;
addPawnDoubleMovesByMask(moveList, m, -16);
m = (pawns << 7) & BitBoard::maskAToGFiles & (pos.colorBB(!wtm) | epMask);
addPawnMovesByMask<wtm>(moveList, m, -7, true);
m = (pawns << 9) & BitBoard::maskBToHFiles & (pos.colorBB(!wtm) | epMask);
addPawnMovesByMask<wtm>(moveList, m, -9, true);
} else {
U64 m = (pawns >> 8) & ~occupied;
addPawnMovesByMask<wtm>(moveList, m, 8, true);
m = ((m & BitBoard::maskRow6) >> 8) & ~occupied;
addPawnDoubleMovesByMask(moveList, m, 16);
m = (pawns >> 9) & BitBoard::maskAToGFiles & (pos.colorBB(!wtm) | epMask);
addPawnMovesByMask<wtm>(moveList, m, 9, true);
m = (pawns >> 7) & BitBoard::maskBToHFiles & (pos.colorBB(!wtm) | epMask);
addPawnMovesByMask<wtm>(moveList, m, 7, true);
}
}
template void MoveGen::checkEvasions<true>(const Position& pos, MoveList& moveList);
template void MoveGen::checkEvasions<false>(const Position& pos, MoveList& moveList);
template <bool wtm>
void
MoveGen::checkEvasions(const Position& pos, MoveList& moveList) {
typedef ColorTraits<wtm> MyColor;
typedef ColorTraits<!wtm> OtherColor;
const U64 occupied = pos.occupiedBB();
const int kingSq = pos.getKingSq(wtm);
U64 kingThreats = pos.pieceTypeBB(OtherColor::KNIGHT) & BitBoard::knightAttacks[kingSq];
U64 rookPieces = pos.pieceTypeBB(OtherColor::ROOK, OtherColor::QUEEN);
if (rookPieces != 0)
kingThreats |= rookPieces & BitBoard::rookAttacks(kingSq, occupied);
U64 bishPieces = pos.pieceTypeBB(OtherColor::BISHOP, OtherColor::QUEEN);
if (bishPieces != 0)
kingThreats |= bishPieces & BitBoard::bishopAttacks(kingSq, occupied);
const U64 myPawnAttacks = wtm ? BitBoard::wPawnAttacks[kingSq] : BitBoard::bPawnAttacks[kingSq];
kingThreats |= pos.pieceTypeBB(OtherColor::PAWN) & myPawnAttacks;
U64 validTargets = 0;
if ((kingThreats != 0) && ((kingThreats & (kingThreats-1)) == 0)) { // Exactly one attacking piece
int threatSq = BitBoard::numberOfTrailingZeros(kingThreats);
validTargets = kingThreats | BitBoard::squaresBetween[kingSq][threatSq];
}
validTargets |= pos.pieceTypeBB(OtherColor::KING);
// Queen moves
U64 squares = pos.pieceTypeBB(MyColor::QUEEN);
while (squares != 0) {
int sq = BitBoard::numberOfTrailingZeros(squares);
U64 m = (BitBoard::rookAttacks(sq, occupied) | BitBoard::bishopAttacks(sq, occupied)) &
~pos.colorBB(wtm) & validTargets;
addMovesByMask(moveList, sq, m);
squares &= squares-1;
}
// Rook moves
squares = pos.pieceTypeBB(MyColor::ROOK);
while (squares != 0) {
int sq = BitBoard::numberOfTrailingZeros(squares);
U64 m = BitBoard::rookAttacks(sq, occupied) & ~pos.colorBB(wtm) & validTargets;
addMovesByMask(moveList, sq, m);
squares &= squares-1;
}
// Bishop moves
squares = pos.pieceTypeBB(MyColor::BISHOP);
while (squares != 0) {
int sq = BitBoard::numberOfTrailingZeros(squares);
U64 m = BitBoard::bishopAttacks(sq, occupied) & ~pos.colorBB(wtm) & validTargets;
addMovesByMask(moveList, sq, m);
squares &= squares-1;
}
// King moves
{
int sq = pos.getKingSq(wtm);
U64 m = BitBoard::kingAttacks[sq] & ~pos.colorBB(wtm);
addMovesByMask(moveList, sq, m);
}
// Knight moves
U64 knights = pos.pieceTypeBB(MyColor::KNIGHT);
while (knights != 0) {
int sq = BitBoard::numberOfTrailingZeros(knights);
U64 m = BitBoard::knightAttacks[sq] & ~pos.colorBB(wtm) & validTargets;
addMovesByMask(moveList, sq, m);
knights &= knights-1;
}
// Pawn moves
const U64 pawns = pos.pieceTypeBB(MyColor::PAWN);
const int epSquare = pos.getEpSquare();
const U64 epMask = (epSquare >= 0) ? (1ULL << epSquare) : 0ULL;
if (wtm) {
U64 m = (pawns << 8) & ~occupied;
addPawnMovesByMask<wtm>(moveList, m & validTargets, -8, true);
m = ((m & BitBoard::maskRow3) << 8) & ~occupied;
addPawnDoubleMovesByMask(moveList, m & validTargets, -16);
m = (pawns << 7) & BitBoard::maskAToGFiles & ((pos.colorBB(!wtm) & validTargets) | epMask);
addPawnMovesByMask<wtm>(moveList, m, -7, true);
m = (pawns << 9) & BitBoard::maskBToHFiles & ((pos.colorBB(!wtm) & validTargets) | epMask);
addPawnMovesByMask<wtm>(moveList, m, -9, true);
} else {
U64 m = (pawns >> 8) & ~occupied;
addPawnMovesByMask<wtm>(moveList, m & validTargets, 8, true);
m = ((m & BitBoard::maskRow6) >> 8) & ~occupied;
addPawnDoubleMovesByMask(moveList, m & validTargets, 16);
m = (pawns >> 9) & BitBoard::maskAToGFiles & ((pos.colorBB(!wtm) & validTargets) | epMask);
addPawnMovesByMask<wtm>(moveList, m, 9, true);
m = (pawns >> 7) & BitBoard::maskBToHFiles & ((pos.colorBB(!wtm) & validTargets) | epMask);
addPawnMovesByMask<wtm>(moveList, m, 7, true);
}
}
template void MoveGen::pseudoLegalCaptures<true>(const Position& pos, MoveList& moveList);
template void MoveGen::pseudoLegalCaptures<false>(const Position& pos, MoveList& moveList);
template <bool wtm>
void
MoveGen::pseudoLegalCaptures(const Position& pos, MoveList& moveList) {
typedef ColorTraits<wtm> MyColor;
const U64 occupied = pos.occupiedBB();
// Queen moves
U64 squares = pos.pieceTypeBB(MyColor::QUEEN);
while (squares != 0) {
int sq = BitBoard::numberOfTrailingZeros(squares);
U64 m = (BitBoard::rookAttacks(sq, occupied) | BitBoard::bishopAttacks(sq, occupied)) & pos.colorBB(!wtm);
addMovesByMask(moveList, sq, m);
squares &= squares-1;
}
// Rook moves
squares = pos.pieceTypeBB(MyColor::ROOK);
while (squares != 0) {
int sq = BitBoard::numberOfTrailingZeros(squares);
U64 m = BitBoard::rookAttacks(sq, occupied) & pos.colorBB(!wtm);
addMovesByMask(moveList, sq, m);
squares &= squares-1;
}
// Bishop moves
squares = pos.pieceTypeBB(MyColor::BISHOP);
while (squares != 0) {
int sq = BitBoard::numberOfTrailingZeros(squares);
U64 m = BitBoard::bishopAttacks(sq, occupied) & pos.colorBB(!wtm);
addMovesByMask(moveList, sq, m);
squares &= squares-1;
}
// Knight moves
U64 knights = pos.pieceTypeBB(MyColor::KNIGHT);
while (knights != 0) {
int sq = BitBoard::numberOfTrailingZeros(knights);
U64 m = BitBoard::knightAttacks[sq] & pos.colorBB(!wtm);
addMovesByMask(moveList, sq, m);
knights &= knights-1;
}
// King moves
int sq = pos.getKingSq(wtm);
U64 m = BitBoard::kingAttacks[sq] & pos.colorBB(!wtm);
addMovesByMask(moveList, sq, m);
// Pawn moves
const U64 pawns = pos.pieceTypeBB(MyColor::PAWN);
const int epSquare = pos.getEpSquare();
const U64 epMask = (epSquare >= 0) ? (1ULL << epSquare) : 0ULL;
if (wtm) {
m = (pawns << 8) & ~occupied;
m &= BitBoard::maskRow8;
addPawnMovesByMask<wtm>(moveList, m, -8, false);
m = (pawns << 7) & BitBoard::maskAToGFiles & (pos.colorBB(!wtm) | epMask);
addPawnMovesByMask<wtm>(moveList, m, -7, false);
m = (pawns << 9) & BitBoard::maskBToHFiles & (pos.colorBB(!wtm) | epMask);
addPawnMovesByMask<wtm>(moveList, m, -9, false);
} else {
m = (pawns >> 8) & ~occupied;
m &= BitBoard::maskRow1;
addPawnMovesByMask<wtm>(moveList, m, 8, false);
m = (pawns >> 9) & BitBoard::maskAToGFiles & (pos.colorBB(!wtm) | epMask);
addPawnMovesByMask<wtm>(moveList, m, 9, false);
m = (pawns >> 7) & BitBoard::maskBToHFiles & (pos.colorBB(!wtm) | epMask);
addPawnMovesByMask<wtm>(moveList, m, 7, false);
}
}
bool
MoveGen::isLegal(Position& pos, const Move& m, bool isInCheck) {
UndoInfo ui;
int kSq = pos.getKingSq(pos.isWhiteMove());
const int epSquare = pos.getEpSquare();
if (isInCheck) {
if ((m.from() != kSq) && (m.to() != epSquare)) {
U64 occupied = pos.occupiedBB();
U64 toMask = 1ULL << m.to();
Piece::Type knight = pos.isWhiteMove() ? Piece::BKNIGHT : Piece::WKNIGHT;
if (((BitBoard::rookAttacks(kSq, occupied) & toMask) == 0) &&
((BitBoard::bishopAttacks(kSq, occupied) & toMask) == 0) &&
((BitBoard::knightAttacks[kSq] & pos.pieceTypeBB(knight) & toMask) == 0))
return false;
}
pos.makeMove(m, ui);
bool legal = !canTakeKing(pos);
pos.unMakeMove(m, ui);
return legal;
} else {
if (m.from() == kSq) {
U64 occupied = pos.occupiedBB() & ~(1ULL<<m.from());
return !MoveGen::sqAttacked(pos, m.to(), occupied);
} else {
if (m.to() != epSquare) {
U64 occupied = pos.occupiedBB();
U64 fromMask = 1ULL << m.from();
if (((BitBoard::rookAttacks(kSq, occupied) & fromMask) == 0) &&
((BitBoard::bishopAttacks(kSq, occupied) & fromMask) == 0))
return true;
else if (BitBoard::getDirection(kSq, m.from()) == BitBoard::getDirection(kSq, m.to()))
return true;
}
pos.makeMove(m, ui);
bool legal = !canTakeKing(pos);
pos.unMakeMove(m, ui);
return legal;
}
}
}