0x410201CE5C030092ULL
};
-const int BShift[64] = {
- 58, 59, 59, 59, 59, 59, 59, 58, 59, 59, 59, 59, 59, 59, 59, 59,
- 59, 59, 57, 57, 57, 57, 59, 59, 59, 59, 57, 55, 55, 57, 59, 59,
- 59, 59, 57, 55, 55, 57, 59, 59, 59, 59, 57, 57, 57, 57, 59, 59,
- 59, 59, 59, 59, 59, 59, 59, 59, 58, 59, 59, 59, 59, 59, 59, 58
-};
-
-const int RShift[64] = {
- 52, 53, 53, 53, 53, 53, 53, 52, 53, 54, 54, 54, 54, 54, 54, 53,
- 53, 54, 54, 54, 54, 54, 54, 53, 53, 54, 54, 54, 54, 54, 54, 53,
- 53, 54, 54, 54, 54, 54, 54, 53, 53, 54, 54, 54, 54, 54, 54, 53,
- 53, 54, 54, 54, 54, 54, 54, 53, 52, 53, 53, 53, 53, 53, 53, 52
-};
-
#else // if !defined(IS_64BIT)
const uint32_t DeBruijnMagic = 0x783A9B23;
0x5AC08A4735370479ULL,
};
-const int BShift[64] = {
- 26, 27, 27, 27, 27, 27, 27, 26, 27, 27, 27, 27, 27, 27, 27, 27,
- 27, 27, 25, 25, 25, 25, 27, 27, 27, 27, 25, 23, 23, 25, 27, 27,
- 27, 27, 25, 23, 23, 25, 27, 27, 27, 27, 25, 25, 25, 25, 27, 27,
- 27, 27, 27, 27, 27, 27, 27, 27, 26, 27, 27, 27, 27, 27, 27, 26
-};
-
-const int RShift[64] = {
- 20, 21, 21, 21, 21, 21, 21, 20, 21, 22, 22, 22, 22, 22, 22, 21,
- 21, 22, 22, 22, 22, 22, 22, 21, 21, 22, 22, 22, 22, 22, 22, 21,
- 21, 22, 22, 22, 22, 22, 22, 21, 21, 22, 22, 22, 22, 22, 22, 21,
- 21, 22, 22, 22, 22, 22, 22, 21, 20, 21, 21, 21, 21, 21, 21, 20
-};
-
#endif // defined(IS_64BIT)
CACHE_LINE_ALIGNMENT int BSFTable[64];
- void init_sliding_attacks(Bitboard attacks[], Magics m[], const int shift[],
- const Bitboard mult[], Square deltas[]);
+ void init_sliding_attacks(Bitboard attacks[], Magics m[], const Bitboard mult[], Square deltas[]);
}
Square RDeltas[] = { DELTA_N, DELTA_E, DELTA_S, DELTA_W };
Square BDeltas[] = { DELTA_NE, DELTA_SE, DELTA_SW, DELTA_NW };
- init_sliding_attacks(RAttacks, RMagics, RShift, RMult, RDeltas);
- init_sliding_attacks(BAttacks, BMagics, BShift, BMult, BDeltas);
+ init_sliding_attacks(RAttacks, RMagics, RMult, RDeltas);
+ init_sliding_attacks(BAttacks, BMagics, BMult, BDeltas);
for (Square s = SQ_A1; s <= SQ_H8; s++)
{
return subMask;
}
- Bitboard sliding_attacks(Square sq, Bitboard occupied, Square deltas[], bool skipLast) {
+ Bitboard sliding_attacks(Square sq, Bitboard occupied, Square deltas[], Bitboard excluded) {
Bitboard attacks = 0;
while ( square_is_ok(s)
&& square_distance(s, s - deltas[i]) == 1
- && (!skipLast || !file_distance(s, sq) || (square_file(s) != FILE_A && square_file(s) != FILE_H))
- && (!skipLast || !rank_distance(s, sq) || (square_rank(s) != RANK_1 && square_rank(s) != RANK_8)))
+ && !bit_is_set(excluded, s))
{
- attacks |= 1ULL << s;
+ set_bit(&attacks, s);
- if (occupied & (1ULL << s))
+ if (bit_is_set(occupied, s))
break;
s += deltas[i];
return attacks;
}
- void init_sliding_attacks(Bitboard attacks[], Magics m[], const int shift[],
- const Bitboard mult[], Square deltas[]) {
- Bitboard occupancy, index;
+ void init_sliding_attacks(Bitboard attacks[], Magics m[], const Bitboard mult[], Square deltas[]) {
+
+ Bitboard occupancy, index, excluded;
int maxKey, offset = 0;
for (Square s = SQ_A1; s <= SQ_H8; s++)
{
+ excluded = ((Rank1BB | Rank8BB) & ~rank_bb(s)) | ((FileABB | FileHBB) & ~file_bb(s));
+
m[s].offset = offset;
m[s].mult = mult[s];
- m[s].shift = shift[s];
- m[s].mask = sliding_attacks(s, EmptyBoardBB, deltas, true);
+ m[s].mask = sliding_attacks(s, EmptyBoardBB, deltas, excluded);
+ m[s].shift = (CpuIs64Bit ? 64 : 32) - count_1s<CNT64>(m[s].mask);
- maxKey = 1 << (CpuIs64Bit ? 64 - shift[s] : 32 - shift[s]);
+ maxKey = 1 << count_1s<CNT64>(m[s].mask);
for (int key = 0; key < maxKey; key++)
{
index = CpuIs64Bit ? occupancy * mult[s]
: unsigned(occupancy * mult[s] ^ (occupancy >> 32) * (mult[s] >> 32));
- attacks[offset + (index >> shift[s])] = sliding_attacks(s, occupancy, deltas, false);
+ attacks[offset + (index >> m[s].shift)] = sliding_attacks(s, occupancy, deltas, EmptyBoardBB);
}
offset += maxKey;
}