const Bitboard Rank7BB = Rank1BB << (8 * 6);
const Bitboard Rank8BB = Rank1BB << (8 * 7);
-extern Bitboard RMasks[SQUARE_NB];
-extern Bitboard RMagics[SQUARE_NB];
-extern Bitboard* RAttacks[SQUARE_NB];
-extern unsigned RShifts[SQUARE_NB];
+extern Bitboard RookMasks[SQUARE_NB];
+extern Bitboard RookMagics[SQUARE_NB];
+extern Bitboard* RookAttacks[SQUARE_NB];
+extern unsigned RookShifts[SQUARE_NB];
-extern Bitboard BMasks[SQUARE_NB];
-extern Bitboard BMagics[SQUARE_NB];
-extern Bitboard* BAttacks[SQUARE_NB];
-extern unsigned BShifts[SQUARE_NB];
+extern Bitboard BishopMasks[SQUARE_NB];
+extern Bitboard BishopMagics[SQUARE_NB];
+extern Bitboard* BishopAttacks[SQUARE_NB];
+extern unsigned BishopShifts[SQUARE_NB];
extern Bitboard SquareBB[SQUARE_NB];
extern Bitboard FileBB[FILE_NB];
/// a square and a bitboard of occupied squares as input, and returns a bitboard
/// representing all squares attacked by Pt (bishop or rook) on the given square.
template<PieceType Pt>
-FORCE_INLINE unsigned magic_index(Square s, Bitboard occ) {
+FORCE_INLINE unsigned magic_index(Square s, Bitboard occupied) {
- Bitboard* const Masks = Pt == ROOK ? RMasks : BMasks;
- Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics;
- unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts;
+ Bitboard* const Masks = Pt == ROOK ? RookMasks : BishopMasks;
+ Bitboard* const Magics = Pt == ROOK ? RookMagics : BishopMagics;
+ unsigned* const Shifts = Pt == ROOK ? RookShifts : BishopShifts;
if (HasPext)
- return unsigned(_pext_u64(occ, Masks[s]));
+ return unsigned(_pext_u64(occupied, Masks[s]));
if (Is64Bit)
- return unsigned(((occ & Masks[s]) * Magics[s]) >> Shifts[s]);
+ return unsigned(((occupied & Masks[s]) * Magics[s]) >> Shifts[s]);
- unsigned lo = unsigned(occ) & unsigned(Masks[s]);
- unsigned hi = unsigned(occ >> 32) & unsigned(Masks[s] >> 32);
+ unsigned lo = unsigned(occupied) & unsigned(Masks[s]);
+ unsigned hi = unsigned(occupied >> 32) & unsigned(Masks[s] >> 32);
return (lo * unsigned(Magics[s]) ^ hi * unsigned(Magics[s] >> 32)) >> Shifts[s];
}
template<PieceType Pt>
-inline Bitboard attacks_bb(Square s, Bitboard occ) {
- return (Pt == ROOK ? RAttacks : BAttacks)[s][magic_index<Pt>(s, occ)];
+inline Bitboard attacks_bb(Square s, Bitboard occupied) {
+ return (Pt == ROOK ? RookAttacks : BishopAttacks)[s][magic_index<Pt>(s, occupied)];
}
-inline Bitboard attacks_bb(Piece pc, Square s, Bitboard occ) {
+inline Bitboard attacks_bb(Piece pc, Square s, Bitboard occupied) {
switch (type_of(pc))
{
- 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);
+ case BISHOP: return attacks_bb<BISHOP>(s, occupied);
+ case ROOK : return attacks_bb<ROOK>(s, occupied);
+ case QUEEN : return attacks_bb<BISHOP>(s, occupied) | attacks_bb<ROOK>(s, occupied);
default : return StepAttacksBB[pc][s];
}
}