X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.cpp;h=dbaeb701cff9e6e29fc732895a71fda4408bc99e;hp=9adf1407bd5471436e360b79aa4af7eb30f4065a;hb=158864270a055fe20dca4a87f4b7a8aa9cedfeb9;hpb=c9dcda6ac488c0058ebd567e1f52e30b8cd0db20 diff --git a/src/bitboard.cpp b/src/bitboard.cpp index 9adf1407..dbaeb701 100644 --- a/src/bitboard.cpp +++ b/src/bitboard.cpp @@ -18,24 +18,21 @@ */ #include -#include -#include +#include // For memset #include "bitboard.h" #include "bitcount.h" -#include "rkiss.h" +#include "misc.h" -CACHE_LINE_ALIGNMENT +Bitboard RookMasks[SQUARE_NB]; +Bitboard RookMagics[SQUARE_NB]; +Bitboard* RookAttacks[SQUARE_NB]; +unsigned RookShifts[SQUARE_NB]; -Bitboard RMasks[SQUARE_NB]; -Bitboard RMagics[SQUARE_NB]; -Bitboard* RAttacks[SQUARE_NB]; -unsigned RShifts[SQUARE_NB]; - -Bitboard BMasks[SQUARE_NB]; -Bitboard BMagics[SQUARE_NB]; -Bitboard* BAttacks[SQUARE_NB]; -unsigned BShifts[SQUARE_NB]; +Bitboard BishopMasks[SQUARE_NB]; +Bitboard BishopMagics[SQUARE_NB]; +Bitboard* BishopAttacks[SQUARE_NB]; +unsigned BishopShifts[SQUARE_NB]; Bitboard SquareBB[SQUARE_NB]; Bitboard FileBB[FILE_NB]; @@ -59,12 +56,10 @@ namespace { const uint64_t DeBruijn_64 = 0x3F79D71B4CB0A89ULL; const uint32_t DeBruijn_32 = 0x783A9B23; - CACHE_LINE_ALIGNMENT - int MS1BTable[256]; Square BSFTable[SQUARE_NB]; - Bitboard RTable[0x19000]; // Storage space for rook attacks - Bitboard BTable[0x1480]; // Storage space for bishop attacks + Bitboard RookTable[0x19000]; // Storage space for rook attacks + Bitboard BishopTable[0x1480]; // Storage space for bishop attacks typedef unsigned (Fn)(Square, Bitboard); @@ -130,19 +125,17 @@ Square msb(Bitboard b) { const std::string Bitboards::pretty(Bitboard b) { - std::ostringstream ss; + std::string s = "+---+---+---+---+---+---+---+---+\n"; - for (Rank rank = RANK_8; rank >= RANK_1; --rank) + for (Rank r = RANK_8; r >= RANK_1; --r) { - ss << "+---+---+---+---+---+---+---+---+" << '\n'; + for (File f = FILE_A; f <= FILE_H; ++f) + s.append(b & make_square(f, r) ? "| X " : "| "); - for (File file = FILE_A; file <= FILE_H; ++file) - ss << "| " << (b & (file | rank) ? "X " : " "); - - ss << "|\n"; + s.append("|\n+---+---+---+---+---+---+---+---+\n"); } - ss << "+---+---+---+---+---+---+---+---+"; - return ss.str(); + + return s; } @@ -152,7 +145,10 @@ const std::string Bitboards::pretty(Bitboard b) { void Bitboards::init() { for (Square s = SQ_A1; s <= SQ_H8; ++s) - BSFTable[bsf_index(SquareBB[s] = 1ULL << s)] = s; + { + SquareBB[s] = 1ULL << s; + BSFTable[bsf_index(SquareBB[s])] = s; + } for (Bitboard b = 1; b < 256; ++b) MS1BTable[b] = more_than_one(b) ? MS1BTable[b - 1] : lsb(b); @@ -181,7 +177,7 @@ void Bitboards::init() { for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2) if (s1 != s2) { - SquareDistance[s1][s2] = std::max(file_distance(s1, s2), rank_distance(s1, s2)); + SquareDistance[s1][s2] = std::max(distance(s1, s2), distance(s1, s2)); DistanceRingsBB[s1][SquareDistance[s1][s2] - 1] |= s2; } @@ -195,15 +191,15 @@ void Bitboards::init() { { Square to = s + Square(c == WHITE ? steps[pt][i] : -steps[pt][i]); - if (is_ok(to) && square_distance(s, to) < 3) + if (is_ok(to) && distance(s, to) < 3) StepAttacksBB[make_piece(c, pt)][s] |= to; } - Square RDeltas[] = { DELTA_N, DELTA_E, DELTA_S, DELTA_W }; - Square BDeltas[] = { DELTA_NE, DELTA_SE, DELTA_SW, DELTA_NW }; + Square RookDeltas[] = { DELTA_N, DELTA_E, DELTA_S, DELTA_W }; + Square BishopDeltas[] = { DELTA_NE, DELTA_SE, DELTA_SW, DELTA_NW }; - init_magics(RTable, RAttacks, RMagics, RMasks, RShifts, RDeltas, magic_index); - init_magics(BTable, BAttacks, BMagics, BMasks, BShifts, BDeltas, magic_index); + init_magics(RookTable, RookAttacks, RookMagics, RookMasks, RookShifts, RookDeltas, magic_index); + init_magics(BishopTable, BishopAttacks, BishopMagics, BishopMasks, BishopShifts, BishopDeltas, magic_index); for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1) { @@ -233,7 +229,7 @@ namespace { for (int i = 0; i < 4; ++i) for (Square s = sq + deltas[i]; - is_ok(s) && square_distance(s, s - deltas[i]) == 1; + is_ok(s) && distance(s, s - deltas[i]) == 1; s += deltas[i]) { attack |= s; @@ -246,20 +242,6 @@ namespace { } - Bitboard pick_random(RKISS& rk, int booster) { - - // Values s1 and s2 are used to rotate the candidate magic of a - // quantity known to be optimal to quickly find the magics. - int s1 = booster & 63, s2 = (booster >> 6) & 63; - - Bitboard m = rk.rand(); - m = (m >> s1) | (m << (64 - s1)); - m &= rk.rand(); - m = (m >> s2) | (m << (64 - s2)); - return m & rk.rand(); - } - - // init_magics() computes all rook and bishop attacks at startup. Magic // bitboards are used to look up attacks of sliding pieces. As a reference see // chessprogramming.wikispaces.com/Magic+Bitboards. In particular, here we @@ -268,11 +250,10 @@ namespace { void init_magics(Bitboard table[], Bitboard* attacks[], Bitboard magics[], Bitboard masks[], unsigned shifts[], Square deltas[], Fn index) { - int MagicBoosters[][8] = { { 3191, 2184, 1310, 3618, 2091, 1308, 2452, 3996 }, - { 1059, 3608, 605, 3234, 3326, 38, 2029, 3043 } }; - RKISS rk; + int seeds[][RANK_NB] = { { 8977, 44560, 54343, 38998, 5731, 95205, 104912, 17020 }, + { 728, 10316, 55013, 32803, 12281, 15100, 16645, 255 } }; Bitboard occupancy[4096], reference[4096], edges, b; - int i, size, booster; + int i, size; // attacks[s] is a pointer to the beginning of the attacks table for square 's' attacks[SQ_A1] = table; @@ -295,7 +276,12 @@ namespace { b = size = 0; do { occupancy[size] = b; - reference[size++] = sliding_attack(deltas, s, b); + reference[size] = sliding_attack(deltas, s, b); + + if (HasPext) + attacks[s][_pext_u64(b, masks[s])] = reference[size]; + + size++; b = (b - masks[s]) & masks[s]; } while (b); @@ -304,12 +290,16 @@ namespace { if (s < SQ_H8) attacks[s + 1] = attacks[s] + size; - booster = MagicBoosters[Is64Bit][rank_of(s)]; + if (HasPext) + continue; + + PRNG rng(seeds[Is64Bit][rank_of(s)]); // Find a magic for square 's' picking up an (almost) random number // until we find the one that passes the verification test. do { - do magics[s] = pick_random(rk, booster); + do + magics[s] = rng.sparse_rand(); while (popcount((magics[s] * masks[s]) >> 56) < 6); std::memset(attacks[s], 0, size * sizeof(Bitboard)); @@ -325,11 +315,11 @@ namespace { if (attack && attack != reference[i]) break; - assert(reference[i] != 0); + assert(reference[i]); attack = reference[i]; } - } while (i != size); + } while (i < size); } } }