X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.cpp;h=8c1be7390a14a02a04dba241710a27c6550123a1;hp=6f1569250a7fe6681c080733c86370fc32b46f0c;hb=a38b14bd333b73bab84125b272cecf2291f82a27;hpb=8a116ce6910529457a2b82dfa8606cce36415852 diff --git a/src/bitboard.cpp b/src/bitboard.cpp index 6f156925..8c1be739 100644 --- a/src/bitboard.cpp +++ b/src/bitboard.cpp @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2009 Marco Costalba + Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -26,7 +26,6 @@ #include "bitboard.h" #include "bitcount.h" -#include "direction.h" #if defined(IS_64BIT) @@ -163,7 +162,10 @@ const int RShift[64] = { #endif // defined(IS_64BIT) -const Bitboard SquaresByColorBB[2] = { BlackSquaresBB, WhiteSquaresBB }; +const Bitboard LightSquaresBB = 0x55AA55AA55AA55AAULL; +const Bitboard DarkSquaresBB = 0xAA55AA55AA55AA55ULL; + +const Bitboard SquaresByColorBB[2] = { DarkSquaresBB, LightSquaresBB }; const Bitboard FileBB[8] = { FileABB, FileBBB, FileCBB, FileDBB, FileEBB, FileFBB, FileGBB, FileHBB @@ -211,6 +213,8 @@ const Bitboard InFrontBB[2][8] = { } }; +// Global bitboards definitions with static storage duration are +// automatically set to zero before enter main(). Bitboard RMask[64]; int RAttackIndex[64]; Bitboard RAttacks[0x19000]; @@ -222,12 +226,12 @@ Bitboard BAttacks[0x1480]; Bitboard SetMaskBB[65]; Bitboard ClearMaskBB[65]; -Bitboard StepAttackBB[16][64]; -Bitboard RayBB[64][8]; +Bitboard NonSlidingAttacksBB[16][64]; Bitboard BetweenBB[64][64]; +Bitboard SquaresInFrontMask[2][64]; Bitboard PassedPawnMask[2][64]; -Bitboard OutpostMask[2][64]; +Bitboard AttackSpanMask[2][64]; Bitboard BishopPseudoAttacks[64]; Bitboard RookPseudoAttacks[64]; @@ -236,58 +240,34 @@ Bitboard QueenPseudoAttacks[64]; uint8_t BitCount8Bit[256]; -//// -//// Local definitions -//// - namespace { void init_masks(); - void init_ray_bitboards(); - void init_attacks(); + void init_non_sliding_attacks(); + void init_pseudo_attacks(); void init_between_bitboards(); + Bitboard index_to_bitboard(int index, Bitboard mask); Bitboard sliding_attacks(int sq, Bitboard block, int dirs, int deltas[][2], int fmin, int fmax, int rmin, int rmax); - Bitboard index_to_bitboard(int index, Bitboard mask); - void init_sliding_attacks(Bitboard attacks[], - int attackIndex[], Bitboard mask[], - const int shift[2], const Bitboard mult[], - int deltas[][2]); - void init_pseudo_attacks(); + void init_sliding_attacks(Bitboard attacks[], int attackIndex[], Bitboard mask[], + const int shift[], const Bitboard mult[], int deltas[][2]); } -//// -//// Functions -//// - /// print_bitboard() prints a bitboard in an easily readable format to the -/// standard output. This is sometimes useful for debugging. +/// standard output. This is sometimes useful for debugging. void print_bitboard(Bitboard b) { - for(Rank r = RANK_8; r >= RANK_1; r--) { - std::cout << "+---+---+---+---+---+---+---+---+" << std::endl; - for(File f = FILE_A; f <= FILE_H; f++) - std::cout << "| " << (bit_is_set(b, make_square(f, r))? 'X' : ' ') << ' '; - std::cout << "|" << std::endl; - } - std::cout << "+---+---+---+---+---+---+---+---+" << std::endl; -} + for (Rank r = RANK_8; r >= RANK_1; r--) + { + std::cout << "+---+---+---+---+---+---+---+---+" << '\n'; + for (File f = FILE_A; f <= FILE_H; f++) + std::cout << "| " << (bit_is_set(b, make_square(f, r))? 'X' : ' ') << ' '; -/// init_bitboards() initializes various bitboard arrays. It is called during -/// program initialization. - -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}}; - init_masks(); - init_ray_bitboards(); - init_attacks(); - init_between_bitboards(); - init_sliding_attacks(RAttacks, RAttackIndex, RMask, RShift, RMult, rookDeltas); - init_sliding_attacks(BAttacks, BAttackIndex, BMask, BShift, BMult, bishopDeltas); - init_pseudo_attacks(); + std::cout << "|\n"; + } + std::cout << "+---+---+---+---+---+---+---+---+" << std::endl; } @@ -297,8 +277,8 @@ void init_bitboards() { #if defined(IS_64BIT) && !defined(USE_BSFQ) -CACHE_LINE_ALIGNMENT -static const int BitTable[64] = { +static CACHE_LINE_ALIGNMENT +const int BitTable[64] = { 0, 1, 2, 7, 3, 13, 8, 19, 4, 25, 14, 28, 9, 34, 20, 40, 5, 17, 26, 38, 15, 46, 29, 48, 10, 31, 35, 54, 21, 50, 41, 57, 63, 6, 12, 18, 24, 27, 33, 39, 16, 37, 45, 47, 30, 53, 49, 56, 62, 11, 23, 32, 36, 44, 52, 55, 61, 22, 43, @@ -326,6 +306,7 @@ const int BitTable[64] = { }; Square first_1(Bitboard b) { + b ^= (b - 1); uint32_t fold = int(b) ^ int(b >> 32); return Square(BitTable[(fold * 0x783a9b23) >> 26]); @@ -348,24 +329,43 @@ union b_union { Square pop_1st_bit(Bitboard* bb) { - b_union* u; + b_union u; Square ret; - u = (b_union*)bb; + u.b = *bb; - if (u->dw.l) + if (u.dw.l) { - ret = Square(BitTable[((u->dw.l ^ (u->dw.l - 1)) * 0x783a9b23) >> 26]); - u->dw.l &= (u->dw.l - 1); + ret = Square(BitTable[((u.dw.l ^ (u.dw.l - 1)) * 0x783a9b23) >> 26]); + u.dw.l &= (u.dw.l - 1); + *bb = u.b; return ret; } - ret = Square(BitTable[((~(u->dw.h ^ (u->dw.h - 1))) * 0x783a9b23) >> 26]); - u->dw.h &= (u->dw.h - 1); + ret = Square(BitTable[((~(u.dw.h ^ (u.dw.h - 1))) * 0x783a9b23) >> 26]); + u.dw.h &= (u.dw.h - 1); + *bb = u.b; return ret; } #endif + +/// init_bitboards() initializes various bitboard arrays. It is called during +/// program initialization. + +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}}; + + init_masks(); + init_non_sliding_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(); +} + namespace { // All functions below are used to precompute various bitboards during @@ -374,146 +374,148 @@ namespace { // be necessary to touch any of them. void init_masks() { - SetMaskBB[SQ_NONE] = 0ULL; + + SetMaskBB[SQ_NONE] = EmptyBoardBB; ClearMaskBB[SQ_NONE] = ~SetMaskBB[SQ_NONE]; - for(Square s = SQ_A1; s <= SQ_H8; s++) { - SetMaskBB[s] = (1ULL << s); - ClearMaskBB[s] = ~SetMaskBB[s]; + + for (Square s = SQ_A1; s <= SQ_H8; s++) + { + SetMaskBB[s] = (1ULL << s); + ClearMaskBB[s] = ~SetMaskBB[s]; } - for(Color c = WHITE; c <= BLACK; c++) - for(Square s = SQ_A1; s <= SQ_H8; s++) { - PassedPawnMask[c][s] = - in_front_bb(c, s) & this_and_neighboring_files_bb(s); - OutpostMask[c][s] = in_front_bb(c, s) & neighboring_files_bb(s); - } - - for (Bitboard b = 0ULL; b < 256ULL; b++) - BitCount8Bit[b] = (uint8_t)count_1s(b); - } + 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); + } - void init_ray_bitboards() { - int d[8] = {1, -1, 16, -16, 17, -17, 15, -15}; - for(int i = 0; i < 128; i = (i + 9) & ~8) { - for(int j = 0; j < 8; j++) { - RayBB[(i&7)|((i>>4)<<3)][j] = EmptyBoardBB; - for(int k = i + d[j]; (k & 0x88) == 0; k += d[j]) - set_bit(&(RayBB[(i&7)|((i>>4)<<3)][j]), Square((k&7)|((k>>4)<<3))); - } - } + for (Bitboard b = 0; b < 256; b++) + BitCount8Bit[b] = (uint8_t)count_1s(b); } + void init_non_sliding_attacks() { - void init_attacks() { - int i, j, k, l; - int step[16][8] = { + const int step[][9] = { {0}, - {7,9,0}, {17,15,10,6,-6,-10,-15,-17}, {9,7,-7,-9,0}, {8,1,-1,-8,0}, - {9,7,-7,-9,8,1,-1,-8}, {9,7,-7,-9,8,1,-1,-8}, {0}, {0}, - {-7,-9,0}, {17,15,10,6,-6,-10,-15,-17}, {9,7,-7,-9,0}, {8,1,-1,-8,0}, - {9,7,-7,-9,8,1,-1,-8}, {9,7,-7,-9,8,1,-1,-8} + {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(i = 0; i < 64; i++) { - for(j = 0; j <= int(BK); j++) { - StepAttackBB[j][i] = EmptyBoardBB; - for(k = 0; k < 8 && step[j][k] != 0; k++) { - l = i + step[j][k]; - if(l >= 0 && l < 64 && abs((i&7) - (l&7)) < 3) - StepAttackBB[j][i] |= (1ULL << l); - } - } - } - } + 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(&NonSlidingAttacksBB[pc][s], to); + } + } Bitboard sliding_attacks(int sq, Bitboard block, int dirs, int deltas[][2], int fmin=0, int fmax=7, int rmin=0, int rmax=7) { - Bitboard result = 0ULL; - int rk = sq / 8, fl = sq % 8, r, f, i; - for(i = 0; i < dirs; i++) { - int dx = deltas[i][0], dy = deltas[i][1]; - for(f = fl+dx, r = rk+dy; - (dx==0 || (f>=fmin && f<=fmax)) && (dy==0 || (r>=rmin && r<=rmax)); - f += dx, r += dy) { - result |= (1ULL << (f + r*8)); - if(block & (1ULL << (f + r*8))) break; - } + Bitboard result = 0; + int rk = sq / 8; + int fl = sq % 8; + + for (int i = 0; i < dirs; i++) + { + int dx = deltas[i][0]; + int dy = deltas[i][1]; + int f = fl + dx; + int r = rk + dy; + + while ( (dx == 0 || (f >= fmin && f <= fmax)) + && (dy == 0 || (r >= rmin && r <= rmax))) + { + result |= (1ULL << (f + r*8)); + if (block & (1ULL << (f + r*8))) + break; + + f += dx; + r += dy; + } } return result; } + Bitboard index_to_bitboard(int index, Bitboard mask) { - void init_between_bitboards() { - SquareDelta step[8] = { - DELTA_E, DELTA_W, DELTA_N, DELTA_S, DELTA_NE, DELTA_SW, DELTA_NW, DELTA_SE - }; - SignedDirection d; - for(Square s1 = SQ_A1; s1 <= SQ_H8; s1++) - for(Square s2 = SQ_A1; s2 <= SQ_H8; s2++) { - BetweenBB[s1][s2] = EmptyBoardBB; - d = signed_direction_between_squares(s1, s2); - if(d != SIGNED_DIR_NONE) - for(Square s3 = s1 + step[d]; s3 != s2; s3 += step[d]) - set_bit(&(BetweenBB[s1][s2]), s3); - } - } + Bitboard result = EmptyBoardBB; + int sq, cnt = 0; + while (mask) + { + sq = pop_1st_bit(&mask); - Bitboard index_to_bitboard(int index, Bitboard mask) { - int i, j, bits = count_1s(mask); - Bitboard result = 0ULL; - for(i = 0; i < bits; i++) { - j = pop_1st_bit(&mask); - if(index & (1 << i)) result |= (1ULL << j); + 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]) { - void init_sliding_attacks(Bitboard attacks[], - int attackIndex[], Bitboard mask[], - const int shift[2], const Bitboard mult[], - int deltas[][2]) { - int i, j, k, index = 0; - Bitboard b; - for(i = 0; i < 64; i++) { - attackIndex[i] = index; - mask[i] = sliding_attacks(i, 0ULL, 4, deltas, 1, 6, 1, 6); + for (int i = 0, index = 0; i < 64; i++) + { + attackIndex[i] = index; + mask[i] = sliding_attacks(i, 0, 4, deltas, 1, 6, 1, 6); #if defined(IS_64BIT) - j = (1 << (64 - shift[i])); + int j = (1 << (64 - shift[i])); #else - j = (1 << (32 - shift[i])); + int j = (1 << (32 - shift[i])); #endif - for(k = 0; k < j; k++) { - + for (int k = 0; k < j; k++) + { #if defined(IS_64BIT) - b = index_to_bitboard(k, mask[i]); - attacks[index + ((b * mult[i]) >> shift[i])] = - sliding_attacks(i, b, 4, deltas); + Bitboard b = index_to_bitboard(k, mask[i]); + attacks[index + ((b * mult[i]) >> shift[i])] = sliding_attacks(i, b, 4, deltas); #else - b = index_to_bitboard(k, mask[i]); - attacks[index + - (unsigned(int(b) * int(mult[i]) ^ - int(b >> 32) * int(mult[i] >> 32)) - >> shift[i])] = - sliding_attacks(i, b, 4, deltas); + Bitboard b = index_to_bitboard(k, mask[i]); + unsigned v = int(b) * int(mult[i]) ^ int(b >> 32) * int(mult[i] >> 32); + attacks[index + (v >> shift[i])] = sliding_attacks(i, b, 4, deltas); #endif - } - index += j; + } + index += j; } } - void init_pseudo_attacks() { - Square s; - for(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); + + 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; + SquareDelta 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 = SquareDelta(s2 - s1) / Max(f, r); + + for (s3 = s1 + d; s3 != s2; s3 += d) + set_bit(&(BetweenBB[s1][s2]), s3); + } + } + }