#include "types.h"
+namespace Bitboards {
+
+extern void init();
+extern void print(Bitboard b);
+
+}
+
+CACHE_LINE_ALIGNMENT
+
extern Bitboard RMasks[64];
extern Bitboard RMagics[64];
extern Bitboard* RAttacks[64];
-extern int RShifts[64];
+extern unsigned RShifts[64];
extern Bitboard BMasks[64];
extern Bitboard BMagics[64];
extern Bitboard* BAttacks[64];
-extern int BShifts[64];
+extern unsigned BShifts[64];
extern Bitboard SquareBB[64];
extern Bitboard FileBB[8];
extern Bitboard PseudoAttacks[6][64];
-/// Functions for testing whether a given bit is set in a bitboard, and for
-/// setting and clearing bits.
+/// Overloads of bitwise operators between a Bitboard and a Square for testing
+/// whether a given bit is set in a bitboard, and for setting and clearing bits.
-inline Bitboard bit_is_set(Bitboard b, Square s) {
+inline Bitboard operator&(Bitboard b, Square s) {
return b & SquareBB[s];
}
-inline void set_bit(Bitboard* b, Square s) {
- *b |= SquareBB[s];
+inline Bitboard& operator|=(Bitboard& b, Square s) {
+ return b |= SquareBB[s];
}
-inline void xor_bit(Bitboard* b, Square s) {
- *b ^= SquareBB[s];
+inline Bitboard& operator^=(Bitboard& b, Square s) {
+ return b ^= SquareBB[s];
}
-
-/// Functions used to update a bitboard after a move. This is faster
-/// then calling a sequence of clear_bit() + set_bit()
-
-inline Bitboard make_move_bb(Square from, Square to) {
- return SquareBB[from] | SquareBB[to];
+inline Bitboard operator|(Bitboard b, Square s) {
+ return b | SquareBB[s];
}
-inline void do_move_bb(Bitboard* b, Bitboard move_bb) {
- *b ^= move_bb;
+inline Bitboard operator^(Bitboard b, Square s) {
+ return b ^ SquareBB[s];
}
}
-/// Functions for computing sliding attack bitboards. rook_attacks_bb(),
-/// bishop_attacks_bb() and queen_attacks_bb() all take a square and a
-/// bitboard of occupied squares as input, and return a bitboard representing
-/// all squares attacked by a rook, bishop or queen on the given square.
+/// Functions for computing sliding attack bitboards. Function attacks_bb() takes
+/// 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) {
-#if defined(IS_64BIT)
+ Bitboard* const Masks = Pt == ROOK ? RMasks : BMasks;
+ Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics;
+ unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts;
-FORCE_INLINE unsigned r_index(Square s, Bitboard occ) {
- return unsigned(((occ & RMasks[s]) * RMagics[s]) >> RShifts[s]);
-}
+ if (Is64Bit)
+ return unsigned(((occ & Masks[s]) * Magics[s]) >> Shifts[s]);
-FORCE_INLINE unsigned b_index(Square s, Bitboard occ) {
- return unsigned(((occ & BMasks[s]) * BMagics[s]) >> BShifts[s]);
+ unsigned lo = unsigned(occ) & unsigned(Masks[s]);
+ unsigned hi = unsigned(occ >> 32) & unsigned(Masks[s] >> 32);
+ return (lo * unsigned(Magics[s]) ^ hi * unsigned(Magics[s] >> 32)) >> Shifts[s];
}
-#else // if !defined(IS_64BIT)
-
-FORCE_INLINE unsigned r_index(Square s, Bitboard occ) {
- Bitboard b = occ & RMasks[s];
- return unsigned(int(b) * int(RMagics[s]) ^ int(b >> 32) * int(RMagics[s] >> 32)) >> RShifts[s];
-}
-
-FORCE_INLINE unsigned b_index(Square s, Bitboard occ) {
- Bitboard b = occ & BMasks[s];
- return unsigned(int(b) * int(BMagics[s]) ^ int(b >> 32) * int(BMagics[s] >> 32)) >> BShifts[s];
-}
-
-#endif
-
-inline Bitboard rook_attacks_bb(Square s, Bitboard occ) {
- return RAttacks[s][r_index(s, occ)];
-}
-
-inline Bitboard bishop_attacks_bb(Square s, Bitboard occ) {
- return BAttacks[s][b_index(s, occ)];
+template<PieceType Pt>
+inline Bitboard attacks_bb(Square s, Bitboard occ) {
+ Bitboard** const Attacks = Pt == ROOK ? RAttacks : BAttacks;
+ return Attacks[s][magic_index<Pt>(s, occ)];
}
/// the same color of the given square.
inline Bitboard same_color_squares(Square s) {
- return bit_is_set(0xAA55AA55AA55AA55ULL, s) ? 0xAA55AA55AA55AA55ULL
- : ~0xAA55AA55AA55AA55ULL;
+ return Bitboard(0xAA55AA55AA55AA55ULL) & s ? 0xAA55AA55AA55AA55ULL
+ : ~0xAA55AA55AA55AA55ULL;
+}
+
+
+/// single_bit() returns true if in the 'b' bitboard is set a single bit (or if
+/// b == 0).
+
+inline bool single_bit(Bitboard b) {
+ return !(b & (b - 1));
}
#if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
FORCE_INLINE Square first_1(Bitboard b) {
- unsigned long index;
- _BitScanForward64(&index, b);
- return (Square) index;
+ unsigned long index;
+ _BitScanForward64(&index, b);
+ return (Square) index;
+}
+
+FORCE_INLINE Square last_1(Bitboard b) {
+ unsigned long index;
+ _BitScanReverse64(&index, b);
+ return (Square) index;
}
#else
__asm__("bsfq %1, %0": "=r"(dummy): "rm"(b) );
return (Square) dummy;
}
+
+FORCE_INLINE Square last_1(Bitboard b) {
+ Bitboard dummy;
+ __asm__("bsrq %1, %0": "=r"(dummy): "rm"(b) );
+ return (Square) dummy;
+}
#endif
FORCE_INLINE Square pop_1st_bit(Bitboard* b) {
#else // if !defined(USE_BSFQ)
extern Square first_1(Bitboard b);
+extern Square last_1(Bitboard b);
extern Square pop_1st_bit(Bitboard* b);
#endif
-
-extern void print_bitboard(Bitboard b);
-extern void bitboards_init();
-
#endif // !defined(BITBOARD_H_INCLUDED)