// Global bitboards definitions with static storage duration are
// automatically set to zero before enter main().
-Bitboard RAttacks[0x19000];
-Bitboard BAttacks[0x1480];
-
Magics RMagics[64];
Magics BMagics[64];
namespace {
+ CACHE_LINE_ALIGNMENT
+
+ int BSFTable[64];
+
+ Bitboard RAttacks[0x19000];
+ Bitboard BAttacks[0x1480];
+
+ void init_sliding_attacks(Bitboard attacks[], Magics m[], const Bitboard mult[], Square deltas[]);
+
#if defined(IS_64BIT)
const uint64_t DeBruijnMagic = 0x218A392CD3D5DBFULL;
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[], int deltas[][2]);
}
set_bit(&StepAttacksBB[make_piece(c, pt)][s], to);
}
- int rookDeltas[4][2] = { {0,1}, {0 ,-1}, {1, 0}, {-1, 0} };
- int bishopDeltas[4][2] = { {1,1}, {-1, 1}, {1,-1}, {-1,-1} };
+ 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, rookDeltas);
- init_sliding_attacks(BAttacks, BMagics, BShift, BMult, bishopDeltas);
+ init_sliding_attacks(RAttacks, RMagics, RMult, RDeltas);
+ init_sliding_attacks(BAttacks, BMagics, BMult, BDeltas);
for (Square s = SQ_A1; s <= SQ_H8; s++)
{
namespace {
- Bitboard index_to_bitboard(int index, Bitboard mask) {
+ Bitboard submask(Bitboard mask, int key) {
- Bitboard result = 0;
- int sq, cnt = 0;
+ Bitboard subMask = 0;
+ int bitNum = -1;
- while (mask)
- {
- sq = pop_1st_bit(&mask);
+ // Extract an unique submask out of a mask according to the given key
+ for (Square s = SQ_A1; s <= SQ_H8; s++)
+ if (bit_is_set(mask, s) && bit_is_set(key, Square(++bitNum)))
+ set_bit(&subMask, s);
- if (index & (1 << cnt++))
- result |= (1ULL << sq);
- }
- return result;
+ return subMask;
}
- Bitboard sliding_attacks(int sq, Bitboard occupied, int deltas[][2],
- int fmin, int fmax, int rmin, int rmax) {
+ Bitboard sliding_attacks(Square sq, Bitboard occupied, Square deltas[], Bitboard excluded) {
+
Bitboard attacks = 0;
- int dx, dy, f, r;
- int rk = sq / 8;
- int fl = sq % 8;
for (int i = 0; i < 4; i++)
{
- dx = deltas[i][0];
- dy = deltas[i][1];
- f = fl + dx;
- r = rk + dy;
+ Square s = sq + deltas[i];
- while ( (dx == 0 || (f >= fmin && f <= fmax))
- && (dy == 0 || (r >= rmin && r <= rmax)))
+ while ( square_is_ok(s)
+ && square_distance(s, s - deltas[i]) == 1
+ && !bit_is_set(excluded, s))
{
- attacks |= (1ULL << (f + r * 8));
+ set_bit(&attacks, s);
- if (occupied & (1ULL << (f + r * 8)))
+ if (bit_is_set(occupied, s))
break;
- f += dx;
- r += dy;
+ s += deltas[i];
}
}
return attacks;
}
- void init_sliding_attacks(Bitboard attacks[], Magics m[], const int shift[],
- const Bitboard mult[], int deltas[][2]) {
- Bitboard b, v;
- int i, j, index;
+ void init_sliding_attacks(Bitboard attacks[], Magics m[], const Bitboard mult[], Square deltas[]) {
- for (i = index = 0; i < 64; i++)
+ Bitboard occupancy, index, excluded;
+ int maxKey, offset = 0;
+
+ for (Square s = SQ_A1; s <= SQ_H8; s++)
{
- m[i].index = index;
- m[i].mult = mult[i];
- m[i].shift = shift[i];
- m[i].mask = sliding_attacks(i, 0, deltas, 1, 6, 1, 6);
- j = 1 << ((CpuIs64Bit ? 64 : 32) - m[i].shift);
+ excluded = ((Rank1BB | Rank8BB) & ~rank_bb(s)) | ((FileABB | FileHBB) & ~file_bb(s));
+
+ m[s].attacks = &attacks[offset];
+ m[s].mult = mult[s];
+ m[s].mask = sliding_attacks(s, EmptyBoardBB, deltas, excluded);
+ m[s].shift = (CpuIs64Bit ? 64 : 32) - count_1s<CNT64>(m[s].mask);
+
+ maxKey = 1 << count_1s<CNT64>(m[s].mask);
- for (int k = 0; k < j; k++)
+ for (int key = 0; key < maxKey; key++)
{
- b = index_to_bitboard(k, m[i].mask);
- v = CpuIs64Bit ? b * mult[i] : unsigned(b * mult[i] ^ (b >> 32) * (mult[i] >> 32));
- attacks[index + (v >> shift[i])] = sliding_attacks(i, b, deltas, 0, 7, 0, 7);
+ occupancy = submask(m[s].mask, key);
+
+ index = CpuIs64Bit ? occupancy * mult[s]
+ : unsigned(occupancy * mult[s] ^ (occupancy >> 32) * (mult[s] >> 32));
+
+ m[s].attacks[index >> m[s].shift] = sliding_attacks(s, occupancy, deltas, EmptyBoardBB);
}
- index += j;
+ offset += maxKey;
}
}
}
projects / stockfish / blobdiff