/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008 Marco Costalba
+ Copyright (C) 2008-2009 Marco Costalba
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#if !defined(BITBOARD_H_INCLUDED)
#define BITBOARD_H_INCLUDED
-
-////
-//// Defines
-////
-
-// Comment following define if you prefer manually adjust
-// platform macros defined below
-#define AUTO_CONFIGURATION
-
-// Quiet a warning on Intel compiler
-#if !defined(__SIZEOF_INT__ )
-#define __SIZEOF_INT__ 0
-#endif
-
-// Check for 64 bits for different compilers: Intel, MSVC and gcc
-#if defined(__x86_64) || defined(_WIN64) || (__SIZEOF_INT__ > 4)
-#define IS_64BIT
-#endif
-
-#if !defined(AUTO_CONFIGURATION) || defined(IS_64BIT)
-
-//#define USE_COMPACT_ROOK_ATTACKS
-//#define USE_32BIT_ATTACKS
-#define USE_FOLDED_BITSCAN
-
-#define BITCOUNT_SWAR_64
-//#define BITCOUNT_SWAR_32
-//#define BITCOUNT_LOOP
-
-#else
-
-#define USE_32BIT_ATTACKS
-#define USE_FOLDED_BITSCAN
-#define BITCOUNT_SWAR_32
-
-#endif
-
////
//// Includes
////
#include "types.h"
-////
-//// Types
-////
-
-typedef uint64_t Bitboard;
-
-
////
//// Constants and variables
////
const Bitboard WhiteSquaresBB = 0x55AA55AA55AA55AAULL;
const Bitboard BlackSquaresBB = 0xAA55AA55AA55AA55ULL;
-extern const Bitboard SquaresByColorBB[2];
-
const Bitboard FileABB = 0x0101010101010101ULL;
const Bitboard FileBBB = 0x0202020202020202ULL;
const Bitboard FileCBB = 0x0404040404040404ULL;
const Bitboard FileGBB = 0x4040404040404040ULL;
const Bitboard FileHBB = 0x8080808080808080ULL;
-extern const Bitboard FileBB[8];
-extern const Bitboard NeighboringFilesBB[8];
-extern const Bitboard ThisAndNeighboringFilesBB[8];
-
const Bitboard Rank1BB = 0xFFULL;
const Bitboard Rank2BB = 0xFF00ULL;
const Bitboard Rank3BB = 0xFF0000ULL;
const Bitboard Rank7BB = 0xFF000000000000ULL;
const Bitboard Rank8BB = 0xFF00000000000000ULL;
+extern const Bitboard SquaresByColorBB[2];
+extern const Bitboard FileBB[8];
+extern const Bitboard NeighboringFilesBB[8];
+extern const Bitboard ThisAndNeighboringFilesBB[8];
extern const Bitboard RankBB[8];
extern const Bitboard RelativeRankBB[2][8];
extern const Bitboard InFrontBB[2][8];
extern Bitboard PassedPawnMask[2][64];
extern Bitboard OutpostMask[2][64];
-#if defined(USE_COMPACT_ROOK_ATTACKS)
-extern Bitboard RankAttacks[8][64], FileAttacks[8][64];
-#else
extern const uint64_t RMult[64];
extern const int RShift[64];
extern Bitboard RMask[64];
extern int RAttackIndex[64];
extern Bitboard RAttacks[0x19000];
-#endif // defined(USE_COMPACT_ROOK_ATTACKS)
extern const uint64_t BMult[64];
extern const int BShift[64];
extern Bitboard RookPseudoAttacks[64];
extern Bitboard QueenPseudoAttacks[64];
+extern uint8_t BitCount8Bit[256];
+
////
//// Inline functions
}
+/// 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;
+}
+
/// rank_bb() and file_bb() gives a bitboard containing all squares on a given
/// file or rank. It is also possible to pass a square as input to these
/// functions.
/// relative_rank_bb() takes a color and a rank as input, and returns a bitboard
/// representing all squares on the given rank from the given color's point of
-/// view. For instance, relative_rank_bb(WHITE, 7) gives all squares on the
+/// view. For instance, relative_rank_bb(WHITE, 7) gives all squares on the
/// 7th rank, while relative_rank_bb(BLACK, 7) gives all squares on the 2nd
/// rank.
}
-/// Functions for computing sliding attack bitboards. rook_attacks_bb(),
+/// 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(USE_COMPACT_ROOK_ATTACKS)
+#if defined(IS_64BIT)
-inline Bitboard file_attacks_bb(Square s, Bitboard blockers) {
- Bitboard b = (blockers >> square_file(s)) & 0x01010101010100ULL;
- return
- FileAttacks[square_rank(s)][(b*0xd6e8802041d0c441ULL)>>58] & file_bb(s);
-}
-
-inline Bitboard rank_attacks_bb(Square s, Bitboard blockers) {
- Bitboard b = (blockers >> ((s & 56) + 1)) & 63;
- return RankAttacks[square_file(s)][b] & rank_bb(s);
+inline Bitboard rook_attacks_bb(Square s, Bitboard blockers) {
+ Bitboard b = blockers & RMask[s];
+ return RAttacks[RAttackIndex[s] + ((b * RMult[s]) >> RShift[s])];
}
-inline Bitboard rook_attacks_bb(Square s, Bitboard blockers) {
- return file_attacks_bb(s, blockers) | rank_attacks_bb(s, blockers);
+inline Bitboard bishop_attacks_bb(Square s, Bitboard blockers) {
+ Bitboard b = blockers & BMask[s];
+ return BAttacks[BAttackIndex[s] + ((b * BMult[s]) >> BShift[s])];
}
-#elif defined(USE_32BIT_ATTACKS)
+#else // if !defined(IS_64BIT)
inline Bitboard rook_attacks_bb(Square s, Bitboard blockers) {
Bitboard b = blockers & RMask[s];
>> RShift[s])];
}
-#else
-
-inline Bitboard rook_attacks_bb(Square s, Bitboard blockers) {
- Bitboard b = blockers & RMask[s];
- return RAttacks[RAttackIndex[s] + ((b * RMult[s]) >> RShift[s])];
-}
-
-#endif
-
-#if defined(USE_32BIT_ATTACKS)
-
inline Bitboard bishop_attacks_bb(Square s, Bitboard blockers) {
Bitboard b = blockers & BMask[s];
return BAttacks[BAttackIndex[s] +
>> BShift[s])];
}
-#else // defined(USE_32BIT_ATTACKS)
-
-inline Bitboard bishop_attacks_bb(Square s, Bitboard blockers) {
- Bitboard b = blockers & BMask[s];
- return BAttacks[BAttackIndex[s] + ((b * BMult[s]) >> BShift[s])];
-}
-
-#endif // defined(USE_32BIT_ATTACKS)
+#endif
inline Bitboard queen_attacks_bb(Square s, Bitboard blockers) {
return rook_attacks_bb(s, blockers) | bishop_attacks_bb(s, blockers);
}
-/// count_1s() counts the number of nonzero bits in a bitboard.
-
-#if defined(BITCOUNT_LOOP)
-
-inline int count_1s(Bitboard b) {
- int r;
- for(r = 0; b; r++, b &= b - 1);
- return r;
-}
-
-inline int count_1s_max_15(Bitboard b) {
- return count_1s(b);
-}
+/// first_1() finds the least significant nonzero bit in a nonzero bitboard.
+/// pop_1st_bit() finds and clears the least significant nonzero bit in a
+/// nonzero bitboard.
-#elif defined(BITCOUNT_SWAR_32)
+#if defined(USE_BSFQ) // Assembly code by Heinz van Saanen
-inline int count_1s(Bitboard b) {
- unsigned w = unsigned(b >> 32), v = unsigned(b);
- v -= ((v >> 1) & 0x77777777) + ((v >> 2) & 0x33333333) + ((v & 0x88888888) >> 3); // 0-4 in 4 bits
- w -= ((w >> 1) & 0x77777777) + ((w >> 2) & 0x33333333) + ((w & 0x88888888) >> 3);
- v = ((v >> 4) + v) & 0x0F0F0F0F; // 0-8 in 8 bits
- v += (((w >> 4) + w) & 0x0F0F0F0F); // 0-16 in 8 bits
- v *= 0x01010101; // mul is fast on amd procs
- return int(v >> 24);
+inline Square first_1(Bitboard b) {
+ Bitboard dummy;
+ __asm__("bsfq %1, %0": "=r"(dummy): "rm"(b) );
+ return (Square)(dummy);
}
-inline int count_1s_max_15(Bitboard b) {
- unsigned w = unsigned(b >> 32), v = unsigned(b);
- v -= ((v >> 1) & 0x77777777) + ((v >> 2) & 0x33333333) + ((v & 0x88888888) >> 3); // 0-4 in 4 bits
- w -= ((w >> 1) & 0x77777777) + ((w >> 2) & 0x33333333) + ((w & 0x88888888) >> 3);
- v += w; // 0-8 in 4 bits
- v *= 0x11111111;
- return int(v >> 28);
+inline Square pop_1st_bit(Bitboard* b) {
+ const Square s = first_1(*b);
+ *b &= ~(1ULL<<s);
+ return s;
}
-#elif defined(BITCOUNT_SWAR_64)
-
-inline int count_1s(Bitboard b) {
- b -= ((b>>1) & 0x5555555555555555ULL);
- b = ((b>>2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL);
- b = ((b>>4) + b) & 0x0F0F0F0F0F0F0F0FULL;
- b *= 0x0101010101010101ULL;
- return int(b >> 56);
-}
+#else // if !defined(USE_BSFQ)
-inline int count_1s_max_15(Bitboard b) {
- b -= (b>>1) & 0x5555555555555555ULL;
- b = ((b>>2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL);
- b *= 0x1111111111111111ULL;
- return int(b >> 60);
-}
+extern Square first_1(Bitboard b);
+extern Square pop_1st_bit(Bitboard* b);
-#endif // BITCOUNT
+#endif
////
extern void print_bitboard(Bitboard b);
extern void init_bitboards();
-extern Square first_1(Bitboard b);
-extern Square pop_1st_bit(Bitboard *b);
+extern int bitScanReverse32(uint32_t b);
#endif // !defined(BITBOARD_H_INCLUDED)
projects / stockfish / blobdiff