From: Marco Costalba Date: Sat, 4 Jun 2011 09:16:44 +0000 (+0100) Subject: Move bitboards initializations under one function X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=91407f4f747206c51c9ef9f26e8e17d8b7872941;hp=025d57855a21822ccb262fed4f5a3f9c14d8e9b2 Move bitboards initializations under one function No functional change. Signed-off-by: Marco Costalba --- diff --git a/src/bitboard.cpp b/src/bitboard.cpp index 426a08f3..fd4cd1ef 100644 --- a/src/bitboard.cpp +++ b/src/bitboard.cpp @@ -196,13 +196,6 @@ namespace { CACHE_LINE_ALIGNMENT int BSFTable[64]; - void init_masks(); - void init_step_attacks(); - void init_pseudo_attacks(); - void init_between_bitboards(); - Bitboard index_to_bitboard(int index, Bitboard mask); - Bitboard sliding_attacks(int sq, Bitboard occupied, int deltas[][2], - int fmin, int fmax, int rmin, int rmax); void init_sliding_attacks(Bitboard attacks[], int attackIndex[], Bitboard mask[], const int shift[], const Bitboard mult[], int deltas[][2]); } @@ -292,109 +285,126 @@ Square pop_1st_bit(Bitboard* bb) { void init_bitboards() { - int rookDeltas[4][2] = {{0,1},{0,-1},{1,0},{-1,0}}; - int bishopDeltas[4][2] = {{1,1},{-1,1},{1,-1},{-1,-1}}; + SquaresByColorBB[DARK] = 0xAA55AA55AA55AA55ULL; + SquaresByColorBB[LIGHT] = ~SquaresByColorBB[DARK]; - init_masks(); - init_step_attacks(); - init_sliding_attacks(RAttacks, RAttackIndex, RMask, RShift, RMult, rookDeltas); - init_sliding_attacks(BAttacks, BAttackIndex, BMask, BShift, BMult, bishopDeltas); - init_pseudo_attacks(); - init_between_bitboards(); -} + for (Square s = SQ_A1; s <= SQ_H8; s++) + { + SetMaskBB[s] = (1ULL << s); + ClearMaskBB[s] = ~SetMaskBB[s]; + } -namespace { + ClearMaskBB[SQ_NONE] = ~EmptyBoardBB; - // All functions below are used to precompute various bitboards during - // program initialization. Some of the functions may be difficult to - // understand, but they all seem to work correctly, and it should never - // be necessary to touch any of them. + FileBB[FILE_A] = FileABB; + RankBB[RANK_1] = Rank1BB; - void init_masks() { + for (int f = FILE_B; f <= FILE_H; f++) + { + FileBB[f] = FileBB[f - 1] << 1; + RankBB[f] = RankBB[f - 1] << 8; + } - SquaresByColorBB[DARK] = 0xAA55AA55AA55AA55ULL; - SquaresByColorBB[LIGHT] = ~SquaresByColorBB[DARK]; + for (int f = FILE_A; f <= FILE_H; f++) + { + NeighboringFilesBB[f] = (f > FILE_A ? FileBB[f - 1] : 0) | (f < FILE_H ? FileBB[f + 1] : 0); + ThisAndNeighboringFilesBB[f] = FileBB[f] | NeighboringFilesBB[f]; + } - FileBB[FILE_A] = FileABB; - RankBB[RANK_1] = Rank1BB; + for (int rw = RANK_7, rb = RANK_2; rw >= RANK_1; rw--, rb++) + { + InFrontBB[WHITE][rw] = InFrontBB[WHITE][rw + 1] | RankBB[rw + 1]; + InFrontBB[BLACK][rb] = InFrontBB[BLACK][rb - 1] | RankBB[rb - 1]; + } - for (int f = FILE_B; f <= FILE_H; f++) - { - FileBB[f] = FileBB[f - 1] << 1; - RankBB[f] = RankBB[f - 1] << 8; - } + for (Color c = WHITE; c <= BLACK; c++) + for (Square s = SQ_A1; s <= SQ_H8; s++) + { + SquaresInFrontMask[c][s] = in_front_bb(c, s) & file_bb(s); + PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_neighboring_files_bb(s); + AttackSpanMask[c][s] = in_front_bb(c, s) & neighboring_files_bb(s); + } + + for (Bitboard b = 0; b < 256; b++) + BitCount8Bit[b] = (uint8_t)count_1s(b); + + for (int i = 1; i < 64; i++) + if (!CpuIs64Bit) // Matt Taylor's folding trick for 32 bit systems + { + Bitboard b = 1ULL << i; + b ^= b - 1; + b ^= b >> 32; + BSFTable[uint32_t(b * DeBruijnMagic) >> 26] = i; + } + else + BSFTable[((1ULL << i) * DeBruijnMagic) >> 58] = i; + + int steps[][9] = { + {0}, {7,9,0}, {17,15,10,6,-6,-10,-15,-17,0}, {0}, {0}, {0}, {9,7,-7,-9,8,1,-1,-8,0} + }; + + for (Color c = WHITE; c <= BLACK; c++) + for (Square s = SQ_A1; s <= SQ_H8; s++) + for (PieceType pt = PAWN; pt <= KING; pt++) + for (int k = 0; steps[pt][k]; k++) + { + Square to = s + Square(c == WHITE ? steps[pt][k] : -steps[pt][k]); + + if (square_is_ok(to) && square_distance(s, to) < 3) + 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} }; - for (int f = FILE_A; f <= FILE_H; f++) - { - NeighboringFilesBB[f] = (f > FILE_A ? FileBB[f - 1] : 0) | (f < FILE_H ? FileBB[f + 1] : 0); - ThisAndNeighboringFilesBB[f] = FileBB[f] | NeighboringFilesBB[f]; - } + init_sliding_attacks(RAttacks, RAttackIndex, RMask, RShift, RMult, rookDeltas); + init_sliding_attacks(BAttacks, BAttackIndex, BMask, BShift, BMult, bishopDeltas); - for (int rw = RANK_7, rb = RANK_2; rw >= RANK_1; rw--, rb++) - { - InFrontBB[WHITE][rw] = InFrontBB[WHITE][rw + 1] | RankBB[rw + 1]; - InFrontBB[BLACK][rb] = InFrontBB[BLACK][rb - 1] | RankBB[rb - 1]; - } + for (Square s = SQ_A1; s <= SQ_H8; s++) + { + BishopPseudoAttacks[s] = bishop_attacks_bb(s, EmptyBoardBB); + RookPseudoAttacks[s] = rook_attacks_bb(s, EmptyBoardBB); + QueenPseudoAttacks[s] = queen_attacks_bb(s, EmptyBoardBB); + } - SetMaskBB[SQ_NONE] = EmptyBoardBB; - ClearMaskBB[SQ_NONE] = ~SetMaskBB[SQ_NONE]; + for (Square s1 = SQ_A1; s1 <= SQ_H8; s1++) + for (Square s2 = SQ_A1; s2 <= SQ_H8; s2++) + if (bit_is_set(QueenPseudoAttacks[s1], s2)) + { + int f = file_distance(s1, s2); + int r = rank_distance(s1, s2); - for (Square s = SQ_A1; s <= SQ_H8; s++) - { - SetMaskBB[s] = (1ULL << s); - ClearMaskBB[s] = ~SetMaskBB[s]; - } + Square d = (s2 - s1) / Max(f, r); - for (Color c = WHITE; c <= BLACK; c++) - for (Square s = SQ_A1; s <= SQ_H8; s++) - { - SquaresInFrontMask[c][s] = in_front_bb(c, s) & file_bb(s); - PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_neighboring_files_bb(s); - AttackSpanMask[c][s] = in_front_bb(c, s) & neighboring_files_bb(s); - } + for (Square s3 = s1 + d; s3 != s2; s3 += d) + set_bit(&BetweenBB[s1][s2], s3); + } +} - for (Bitboard b = 0; b < 256; b++) - BitCount8Bit[b] = (uint8_t)count_1s(b); - for (int i = 1; i < 64; i++) - if (!CpuIs64Bit) // Matt Taylor's folding trick for 32 bit systems - { - Bitboard b = 1ULL << i; - b ^= b - 1; - b ^= b >> 32; - BSFTable[uint32_t(b * DeBruijnMagic) >> 26] = i; - } - else - BSFTable[((1ULL << i) * DeBruijnMagic) >> 58] = i; - } +namespace { + + Bitboard index_to_bitboard(int index, Bitboard mask) { + + Bitboard result = 0; + int sq, cnt = 0; + + while (mask) + { + sq = pop_1st_bit(&mask); - void init_step_attacks() { - - const int step[][9] = { - {0}, - {7,9,0}, {17,15,10,6,-6,-10,-15,-17,0}, {0}, {0}, {0}, - {9,7,-7,-9,8,1,-1,-8,0}, {0}, {0}, - {-7,-9,0}, {17,15,10,6,-6,-10,-15,-17,0}, {0}, {0}, {0}, - {9,7,-7,-9,8,1,-1,-8,0} - }; - - for (Square s = SQ_A1; s <= SQ_H8; s++) - for (Piece pc = WP; pc <= BK; pc++) - for (int k = 0; step[pc][k] != 0; k++) - { - Square to = s + Square(step[pc][k]); - - if (square_is_ok(to) && square_distance(s, to) < 3) - set_bit(&StepAttacksBB[pc][s], to); - } + if (index & (1 << cnt++)) + result |= (1ULL << sq); + } + return result; } Bitboard sliding_attacks(int sq, Bitboard occupied, int deltas[][2], int fmin, int fmax, int rmin, int rmax) { + Bitboard attacks = 0; int dx, dy, f, r; int rk = sq / 8; int fl = sq % 8; - Bitboard attacks = EmptyBoardBB; for (int i = 0; i < 4; i++) { @@ -418,21 +428,6 @@ namespace { return attacks; } - Bitboard index_to_bitboard(int index, Bitboard mask) { - - Bitboard result = EmptyBoardBB; - int sq, cnt = 0; - - while (mask) - { - sq = pop_1st_bit(&mask); - - if (index & (1 << cnt++)) - result |= (1ULL << sq); - } - return result; - } - void init_sliding_attacks(Bitboard attacks[], int attackIndex[], Bitboard mask[], const int shift[], const Bitboard mult[], int deltas[][2]) { Bitboard b, v; @@ -453,34 +448,4 @@ namespace { index += j; } } - - void init_pseudo_attacks() { - - for (Square s = SQ_A1; s <= SQ_H8; s++) - { - BishopPseudoAttacks[s] = bishop_attacks_bb(s, EmptyBoardBB); - RookPseudoAttacks[s] = rook_attacks_bb(s, EmptyBoardBB); - QueenPseudoAttacks[s] = queen_attacks_bb(s, EmptyBoardBB); - } - } - - void init_between_bitboards() { - - Square s1, s2, s3, d; - int f, r; - - for (s1 = SQ_A1; s1 <= SQ_H8; s1++) - for (s2 = SQ_A1; s2 <= SQ_H8; s2++) - if (bit_is_set(QueenPseudoAttacks[s1], s2)) - { - f = file_distance(s1, s2); - r = rank_distance(s1, s2); - - d = (s2 - s1) / Max(f, r); - - for (s3 = s1 + d; s3 != s2; s3 += d) - set_bit(&(BetweenBB[s1][s2]), s3); - } - } - }