/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include "types.h"
+CACHE_LINE_ALIGNMENT
+
+extern Bitboard RMasks[64];
+extern Bitboard RMagics[64];
+extern Bitboard* RAttacks[64];
+extern unsigned RShifts[64];
+
+extern Bitboard BMasks[64];
+extern Bitboard BMagics[64];
+extern Bitboard* BAttacks[64];
+extern unsigned BShifts[64];
+
+extern Bitboard SquareBB[64];
extern Bitboard FileBB[8];
-extern Bitboard NeighboringFilesBB[8];
-extern Bitboard ThisAndNeighboringFilesBB[8];
extern Bitboard RankBB[8];
+extern Bitboard AdjacentFilesBB[8];
+extern Bitboard ThisAndAdjacentFilesBB[8];
extern Bitboard InFrontBB[2][8];
-
-extern Bitboard SetMaskBB[65];
-extern Bitboard ClearMaskBB[65];
-
extern Bitboard StepAttacksBB[16][64];
extern Bitboard BetweenBB[64][64];
-
extern Bitboard SquaresInFrontMask[2][64];
extern Bitboard PassedPawnMask[2][64];
extern Bitboard AttackSpanMask[2][64];
-
-extern uint64_t RMagics[64];
-extern int RShifts[64];
-extern Bitboard RMasks[64];
-extern Bitboard* RAttacks[64];
-
-extern uint64_t BMagics[64];
-extern int BShifts[64];
-extern Bitboard BMasks[64];
-extern Bitboard* BAttacks[64];
-
-extern Bitboard BishopPseudoAttacks[64];
-extern Bitboard RookPseudoAttacks[64];
-extern Bitboard QueenPseudoAttacks[64];
-
-extern uint8_t BitCount8Bit[256];
+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) {
- return b & SetMaskBB[s];
+inline Bitboard operator&(Bitboard b, Square s) {
+ return b & SquareBB[s];
}
-inline void set_bit(Bitboard* b, Square s) {
- *b |= SetMaskBB[s];
+inline Bitboard& operator|=(Bitboard& b, Square s) {
+ return b |= SquareBB[s], b;
}
-inline void clear_bit(Bitboard* b, Square s) {
- *b &= ClearMaskBB[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 SetMaskBB[from] | SetMaskBB[to];
-}
-
-inline void do_move_bb(Bitboard* b, Bitboard move_bb) {
- *b ^= move_bb;
+inline Bitboard& operator^=(Bitboard& b, Square s) {
+ return b ^= SquareBB[s], b;
}
}
-/// neighboring_files_bb takes a file as input and returns a bitboard representing
-/// all squares on the neighboring files.
+/// adjacent_files_bb takes a file as input and returns a bitboard representing
+/// all squares on the adjacent files.
-inline Bitboard neighboring_files_bb(File f) {
- return NeighboringFilesBB[f];
+inline Bitboard adjacent_files_bb(File f) {
+ return AdjacentFilesBB[f];
}
-/// this_and_neighboring_files_bb takes a file as input and returns a bitboard
-/// representing all squares on the given and neighboring files.
+/// this_and_adjacent_files_bb takes a file as input and returns a bitboard
+/// representing all squares on the given and adjacent files.
-inline Bitboard this_and_neighboring_files_bb(File f) {
- return ThisAndNeighboringFilesBB[f];
+inline Bitboard this_and_adjacent_files_bb(File f) {
+ return ThisAndAdjacentFilesBB[f];
}
}
-/// 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.
-
-#if defined(IS_64BIT)
+/// 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) {
-FORCE_INLINE unsigned rook_index(Square s, Bitboard occ) {
- return unsigned(((occ & RMasks[s]) * RMagics[s]) >> RShifts[s]);
-}
+ Bitboard* const Masks = Pt == ROOK ? RMasks : BMasks;
+ Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics;
+ unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts;
-FORCE_INLINE unsigned bishop_index(Square s, Bitboard occ) {
- return unsigned(((occ & BMasks[s]) * BMagics[s]) >> BShifts[s]);
-}
-
-#else // if !defined(IS_64BIT)
-
-FORCE_INLINE unsigned rook_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 bishop_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][rook_index(s, occ)];
-}
+ if (Is64Bit)
+ return unsigned(((occ & Masks[s]) * Magics[s]) >> Shifts[s]);
-inline Bitboard bishop_attacks_bb(Square s, Bitboard occ) {
- return BAttacks[s][bishop_index(s, occ)];
+ 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];
}
-inline Bitboard queen_attacks_bb(Square s, Bitboard blockers) {
- return rook_attacks_bb(s, blockers) | bishop_attacks_bb(s, blockers);
+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)];
}
/// passed_pawn_mask takes a color and a square as input, and returns a
/// bitboard mask which can be used to test if a pawn of the given color on
/// the given square is a passed pawn. Definition of the table is:
-/// PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_neighboring_files_bb(s)
+/// PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_adjacent_files_bb(s)
inline Bitboard passed_pawn_mask(Color c, Square s) {
return PassedPawnMask[c][s];
/// attack_span_mask takes a color and a square as input, and returns a bitboard
/// representing all squares that can be attacked by a pawn of the given color
/// when it moves along its file starting from the given square. Definition is:
-/// AttackSpanMask[c][s] = in_front_bb(c, s) & neighboring_files_bb(s);
+/// AttackSpanMask[c][s] = in_front_bb(c, s) & adjacent_files_bb(s);
inline Bitboard attack_span_mask(Color c, Square s) {
return AttackSpanMask[c][s];
inline bool squares_aligned(Square s1, Square s2, Square s3) {
return (BetweenBB[s1][s2] | BetweenBB[s1][s3] | BetweenBB[s2][s3])
- & ( SetMaskBB[s1] | SetMaskBB[s2] | SetMaskBB[s3]);
+ & ( SquareBB[s1] | SquareBB[s2] | SquareBB[s3]);
}
/// 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;
}
projects / stockfish / blobdiff