#endif // defined(IS_64BIT)
+const Bitboard SquaresByColorBB[2] = { BlackSquaresBB, WhiteSquaresBB };
+
+const Bitboard FileBB[8] = {
+ FileABB, FileBBB, FileCBB, FileDBB, FileEBB, FileFBB, FileGBB, FileHBB
+};
+
+const Bitboard NeighboringFilesBB[8] = {
+ FileBBB, FileABB|FileCBB, FileBBB|FileDBB, FileCBB|FileEBB,
+ FileDBB|FileFBB, FileEBB|FileGBB, FileFBB|FileHBB, FileGBB
+};
+
+const Bitboard ThisAndNeighboringFilesBB[8] = {
+ FileABB|FileBBB, FileABB|FileBBB|FileCBB,
+ FileBBB|FileCBB|FileDBB, FileCBB|FileDBB|FileEBB,
+ FileDBB|FileEBB|FileFBB, FileEBB|FileFBB|FileGBB,
+ FileFBB|FileGBB|FileHBB, FileGBB|FileHBB
+};
+
+const Bitboard RankBB[8] = {
+ Rank1BB, Rank2BB, Rank3BB, Rank4BB, Rank5BB, Rank6BB, Rank7BB, Rank8BB
+};
+
+const Bitboard RelativeRankBB[2][8] = {
+ { Rank1BB, Rank2BB, Rank3BB, Rank4BB, Rank5BB, Rank6BB, Rank7BB, Rank8BB },
+ { Rank8BB, Rank7BB, Rank6BB, Rank5BB, Rank4BB, Rank3BB, Rank2BB, Rank1BB }
+};
+
+const Bitboard InFrontBB[2][8] = {
+ { Rank2BB | Rank3BB | Rank4BB | Rank5BB | Rank6BB | Rank7BB | Rank8BB,
+ Rank3BB | Rank4BB | Rank5BB | Rank6BB | Rank7BB | Rank8BB,
+ Rank4BB | Rank5BB | Rank6BB | Rank7BB | Rank8BB,
+ Rank5BB | Rank6BB | Rank7BB | Rank8BB,
+ Rank6BB | Rank7BB | Rank8BB,
+ Rank7BB | Rank8BB,
+ Rank8BB,
+ EmptyBoardBB
+ },
+ { EmptyBoardBB,
+ Rank1BB,
+ Rank2BB | Rank1BB,
+ Rank3BB | Rank2BB | Rank1BB,
+ Rank4BB | Rank3BB | Rank2BB | Rank1BB,
+ Rank5BB | Rank4BB | Rank3BB | Rank2BB | Rank1BB,
+ Rank6BB | Rank5BB | Rank4BB | Rank3BB | Rank2BB | Rank1BB,
+ Rank7BB | Rank6BB | Rank5BB | Rank4BB | Rank3BB | Rank2BB | Rank1BB
+ }
+};
Bitboard RMask[64];
int RAttackIndex[64];
Bitboard RookPseudoAttacks[64];
Bitboard QueenPseudoAttacks[64];
+uint8_t BitCount8Bit[256];
+
////
//// Local definitions
}
+/// 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.
#if defined(IS_64BIT) && !defined(USE_BSFQ)
+static CACHE_LINE_ALIGNMENT
+const int BitTable[64] = {
+ 0, 1, 2, 7, 3, 13, 8, 19, 4, 25, 14, 28, 9, 34, 20, 40, 5, 17, 26, 38, 15,
+ 46, 29, 48, 10, 31, 35, 54, 21, 50, 41, 57, 63, 6, 12, 18, 24, 27, 33, 39,
+ 16, 37, 45, 47, 30, 53, 49, 56, 62, 11, 23, 32, 36, 44, 52, 55, 61, 22, 43,
+ 51, 60, 42, 59, 58
+};
+
+Square first_1(Bitboard b) {
+ return Square(BitTable[((b & -b) * 0x218a392cd3d5dbfULL) >> 58]);
+}
+
Square pop_1st_bit(Bitboard* b) {
- Bitboard bb = *b ^ (*b - 1);
- uint32_t fold = int(bb) ^ int(bb >> 32);
+ Bitboard bb = *b;
*b &= (*b - 1);
- return Square(BitTable[(fold * 0x783a9b23) >> 26]);
+ return Square(BitTable[((bb & -bb) * 0x218a392cd3d5dbfULL) >> 58]);
}
#elif !defined(USE_BSFQ)
+static CACHE_LINE_ALIGNMENT
+const int BitTable[64] = {
+ 63, 30, 3, 32, 25, 41, 22, 33, 15, 50, 42, 13, 11, 53, 19, 34, 61, 29, 2,
+ 51, 21, 43, 45, 10, 18, 47, 1, 54, 9, 57, 0, 35, 62, 31, 40, 4, 49, 5, 52,
+ 26, 60, 6, 23, 44, 46, 27, 56, 16, 7, 39, 48, 24, 59, 14, 12, 55, 38, 28,
+ 58, 20, 37, 17, 36, 8
+};
+
+Square first_1(Bitboard b) {
+ b ^= (b - 1);
+ uint32_t fold = int(b) ^ int(b >> 32);
+ return Square(BitTable[(fold * 0x783a9b23) >> 26]);
+}
+
// Use type-punning
union b_union {
Bitboard b;
struct {
+#if defined (BIGENDIAN)
+ uint32_t h;
+ uint32_t l;
+#else
uint32_t l;
uint32_t h;
+#endif
} dw;
};
-// WARNING: Needs -fno-strict-aliasing compiler option
Square pop_1st_bit(Bitboard* bb) {
- b_union u;
- uint32_t b;
-
- u.b = *bb;
-
- if (u.dw.l)
- {
- b = u.dw.l;
- *((uint32_t*)bb) = b & (b - 1);
- b ^= (b - 1);
- }
- else
- {
- b = u.dw.h;
- *((uint32_t*)bb+1) = b & (b - 1); // Little endian only?
- b = ~(b ^ (b - 1));
- }
- return Square(BitTable[(b * 0x783a9b23) >> 26]);
+ b_union u;
+ Square ret;
+
+ u.b = *bb;
+
+ if (u.dw.l)
+ {
+ ret = Square(BitTable[((u.dw.l ^ (u.dw.l - 1)) * 0x783a9b23) >> 26]);
+ u.dw.l &= (u.dw.l - 1);
+ *bb = u.b;
+ return ret;
+ }
+ ret = Square(BitTable[((~(u.dw.h ^ (u.dw.h - 1))) * 0x783a9b23) >> 26]);
+ u.dw.h &= (u.dw.h - 1);
+ *bb = u.b;
+ return ret;
}
#endif
+// Optimized bitScanReverse32() implementation by Pascal Georges. Note
+// that first bit is 1, this allow to differentiate between 0 and 1.
+static CACHE_LINE_ALIGNMENT
+const char MsbTable[256] = {
+ 0, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5,
+ 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8
+};
+
+int bitScanReverse32(uint32_t b)
+{
+ int result = 0;
+
+ if (b > 0xFFFF)
+ {
+ b >>= 16;
+ result += 16;
+ }
+ if (b > 0xFF)
+ {
+ b >>= 8;
+ result += 8;
+ }
+ return result + MsbTable[b];
+}
+
namespace {
// All functions below are used to precompute various bitboards during
in_front_bb(c, s) & this_and_neighboring_files_bb(s);
OutpostMask[c][s] = in_front_bb(c, s) & neighboring_files_bb(s);
}
+
+ for (Bitboard b = 0ULL; b < 256ULL; b++)
+ BitCount8Bit[b] = (uint8_t)count_1s(b);
}
projects / stockfish / blobdiff