X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.cpp;h=b1bf4d91e583b3f07f1ac53cb669dce2a4522eb0;hp=fd4cd1ef5dfc5b1d8e22c83b5539ba6b41e8b54f;hb=3092f0c6460c831e666d54389710394c52a86ed9;hpb=91407f4f747206c51c9ef9f26e8e17d8b7872941 diff --git a/src/bitboard.cpp b/src/bitboard.cpp index fd4cd1ef..b1bf4d91 100644 --- a/src/bitboard.cpp +++ b/src/bitboard.cpp @@ -22,9 +22,40 @@ #include "bitboard.h" #include "bitcount.h" +// 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]; + +Bitboard SetMaskBB[65]; +Bitboard ClearMaskBB[65]; + +Bitboard SquaresByColorBB[2]; +Bitboard FileBB[8]; +Bitboard RankBB[8]; +Bitboard NeighboringFilesBB[8]; +Bitboard ThisAndNeighboringFilesBB[8]; +Bitboard InFrontBB[2][8]; +Bitboard StepAttacksBB[16][64]; +Bitboard BetweenBB[64][64]; +Bitboard SquaresInFrontMask[2][64]; +Bitboard PassedPawnMask[2][64]; +Bitboard AttackSpanMask[2][64]; + +Bitboard BishopPseudoAttacks[64]; +Bitboard RookPseudoAttacks[64]; +Bitboard QueenPseudoAttacks[64]; + +uint8_t BitCount8Bit[256]; + +namespace { + #if defined(IS_64BIT) -static const uint64_t DeBruijnMagic = 0x218A392CD3D5DBFULL; +const uint64_t DeBruijnMagic = 0x218A392CD3D5DBFULL; const uint64_t BMult[64] = { 0x0440049104032280ULL, 0x1021023C82008040ULL, 0x0404040082000048ULL, @@ -92,7 +123,7 @@ const int RShift[64] = { #else // if !defined(IS_64BIT) -static const uint32_t DeBruijnMagic = 0x783A9B23; +const uint32_t DeBruijnMagic = 0x783A9B23; const uint64_t BMult[64] = { 0x54142844C6A22981ULL, 0x710358A6EA25C19EULL, 0x704F746D63A4A8DCULL, @@ -160,44 +191,10 @@ const int RShift[64] = { #endif // defined(IS_64BIT) -// Global bitboards definitions with static storage duration are -// automatically set to zero before enter main(). -Bitboard RMask[64]; -int RAttackIndex[64]; -Bitboard RAttacks[0x19000]; - -Bitboard BMask[64]; -int BAttackIndex[64]; -Bitboard BAttacks[0x1480]; - -Bitboard SetMaskBB[65]; -Bitboard ClearMaskBB[65]; - -Bitboard SquaresByColorBB[2]; -Bitboard FileBB[8]; -Bitboard RankBB[8]; -Bitboard NeighboringFilesBB[8]; -Bitboard ThisAndNeighboringFilesBB[8]; -Bitboard InFrontBB[2][8]; -Bitboard StepAttacksBB[16][64]; -Bitboard BetweenBB[64][64]; -Bitboard SquaresInFrontMask[2][64]; -Bitboard PassedPawnMask[2][64]; -Bitboard AttackSpanMask[2][64]; - -Bitboard BishopPseudoAttacks[64]; -Bitboard RookPseudoAttacks[64]; -Bitboard QueenPseudoAttacks[64]; - -uint8_t BitCount8Bit[256]; - - -namespace { - CACHE_LINE_ALIGNMENT int BSFTable[64]; - void init_sliding_attacks(Bitboard attacks[], int attackIndex[], Bitboard mask[], - const int shift[], const Bitboard mult[], int deltas[][2]); + void init_sliding_attacks(Bitboard attacks[], Magics m[], const int shift[], + const Bitboard mult[], Square deltas[]); } @@ -354,11 +351,11 @@ void init_bitboards() { 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, RAttackIndex, RMask, RShift, RMult, rookDeltas); - init_sliding_attacks(BAttacks, BAttackIndex, BMask, BShift, BMult, bishopDeltas); + init_sliding_attacks(RAttacks, RMagics, RShift, RMult, RDeltas); + init_sliding_attacks(BAttacks, BMagics, BShift, BMult, BDeltas); for (Square s = SQ_A1; s <= SQ_H8; s++) { @@ -384,68 +381,67 @@ void init_bitboards() { 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[], bool skipLast) { + 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 + && (!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))) { - attacks |= (1ULL << (f + r * 8)); + attacks |= 1ULL << s; - if (occupied & (1ULL << (f + r * 8))) + if (occupied & (1ULL << s)) break; - f += dx; - r += dy; + s += deltas[i]; } } return attacks; } - void init_sliding_attacks(Bitboard attacks[], int attackIndex[], Bitboard mask[], - 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 int shift[], + const Bitboard mult[], Square deltas[]) { + Bitboard occupancy, index; + int maxKey, offset = 0; - for (i = index = 0; i < 64; i++) + for (Square s = SQ_A1; s <= SQ_H8; s++) { - attackIndex[i] = index; - mask[i] = sliding_attacks(i, 0, deltas, 1, 6, 1, 6); - j = 1 << ((CpuIs64Bit ? 64 : 32) - shift[i]); + m[s].offset = offset; + m[s].mult = mult[s]; + m[s].shift = shift[s]; + m[s].mask = sliding_attacks(s, EmptyBoardBB, deltas, true); + + maxKey = 1 << (CpuIs64Bit ? 64 - shift[s] : 32 - shift[s]); - for (int k = 0; k < j; k++) + for (int key = 0; key < maxKey; key++) { - b = index_to_bitboard(k, mask[i]); - 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)); + + attacks[offset + (index >> shift[s])] = sliding_attacks(s, occupancy, deltas, false); } - index += j; + offset += maxKey; } } }