X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.h;h=599d0120da852fb4b379d27430a3b174e8055537;hp=46f8fbd46a104ad173d80ec73db4608f1f331b73;hb=4dded4e72f9b9582db8adc9a478e9eda5841d8c5;hpb=c52da3b806b74ba5ab5249784d39da8fec3c7465 diff --git a/src/bitboard.h b/src/bitboard.h index 46f8fbd4..599d0120 100644 --- a/src/bitboard.h +++ b/src/bitboard.h @@ -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 @@ //// Includes //// -#include "direction.h" #include "piece.h" #include "square.h" #include "types.h" @@ -36,28 +35,25 @@ //// Constants and variables //// -const Bitboard EmptyBoardBB = 0ULL; - -const Bitboard WhiteSquaresBB = 0x55AA55AA55AA55AAULL; -const Bitboard BlackSquaresBB = 0xAA55AA55AA55AA55ULL; +const Bitboard EmptyBoardBB = 0; const Bitboard FileABB = 0x0101010101010101ULL; -const Bitboard FileBBB = 0x0202020202020202ULL; -const Bitboard FileCBB = 0x0404040404040404ULL; -const Bitboard FileDBB = 0x0808080808080808ULL; -const Bitboard FileEBB = 0x1010101010101010ULL; -const Bitboard FileFBB = 0x2020202020202020ULL; -const Bitboard FileGBB = 0x4040404040404040ULL; -const Bitboard FileHBB = 0x8080808080808080ULL; - -const Bitboard Rank1BB = 0xFFULL; -const Bitboard Rank2BB = 0xFF00ULL; -const Bitboard Rank3BB = 0xFF0000ULL; -const Bitboard Rank4BB = 0xFF000000ULL; -const Bitboard Rank5BB = 0xFF00000000ULL; -const Bitboard Rank6BB = 0xFF0000000000ULL; -const Bitboard Rank7BB = 0xFF000000000000ULL; -const Bitboard Rank8BB = 0xFF00000000000000ULL; +const Bitboard FileBBB = FileABB << 1; +const Bitboard FileCBB = FileABB << 2; +const Bitboard FileDBB = FileABB << 3; +const Bitboard FileEBB = FileABB << 4; +const Bitboard FileFBB = FileABB << 5; +const Bitboard FileGBB = FileABB << 6; +const Bitboard FileHBB = FileABB << 7; + +const Bitboard Rank1BB = 0xFF; +const Bitboard Rank2BB = Rank1BB << (8 * 1); +const Bitboard Rank3BB = Rank1BB << (8 * 2); +const Bitboard Rank4BB = Rank1BB << (8 * 3); +const Bitboard Rank5BB = Rank1BB << (8 * 4); +const Bitboard Rank6BB = Rank1BB << (8 * 5); +const Bitboard Rank7BB = Rank1BB << (8 * 6); +const Bitboard Rank8BB = Rank1BB << (8 * 7); extern const Bitboard SquaresByColorBB[2]; extern const Bitboard FileBB[8]; @@ -71,11 +67,11 @@ extern Bitboard SetMaskBB[65]; extern Bitboard ClearMaskBB[65]; extern Bitboard StepAttackBB[16][64]; -extern Bitboard RayBB[64][8]; extern Bitboard BetweenBB[64][64]; +extern Bitboard SquaresInFrontMask[2][64]; extern Bitboard PassedPawnMask[2][64]; -extern Bitboard OutpostMask[2][64]; +extern Bitboard AttackSpanMask[2][64]; extern const uint64_t RMult[64]; extern const int RShift[64]; @@ -94,6 +90,7 @@ extern Bitboard RookPseudoAttacks[64]; extern Bitboard QueenPseudoAttacks[64]; extern uint8_t BitCount8Bit[256]; +extern int8_t DirectionTable[64][64]; //// @@ -127,9 +124,8 @@ inline void do_move_bb(Bitboard *b, Bitboard move_bb) { *b ^= move_bb; } -/// rank_bb() and file_bb() gives a bitboard containing all squares on a given -/// file or rank. It is also possible to pass a square as input to these -/// functions. +/// rank_bb() and file_bb() take a file or a square as input, and return +/// a bitboard representing all squares on the given file or rank. inline Bitboard rank_bb(Rank r) { return RankBB[r]; @@ -156,7 +152,7 @@ inline Bitboard neighboring_files_bb(File f) { } inline Bitboard neighboring_files_bb(Square s) { - return neighboring_files_bb(square_file(s)); + return NeighboringFilesBB[square_file(s)]; } @@ -169,7 +165,7 @@ inline Bitboard this_and_neighboring_files_bb(File f) { } inline Bitboard this_and_neighboring_files_bb(Square s) { - return this_and_neighboring_files_bb(square_file(s)); + return ThisAndNeighboringFilesBB[square_file(s)]; } @@ -195,7 +191,7 @@ inline Bitboard in_front_bb(Color c, Rank r) { } inline Bitboard in_front_bb(Color c, Square s) { - return in_front_bb(c, square_rank(s)); + return InFrontBB[c][square_rank(s)]; } @@ -208,15 +204,7 @@ inline Bitboard behind_bb(Color c, Rank r) { } inline Bitboard behind_bb(Color c, Square s) { - return in_front_bb(opposite_color(c), square_rank(s)); -} - - -/// ray_bb() gives a bitboard representing all squares along the ray in a -/// given direction from a given square. - -inline Bitboard ray_bb(Square s, SignedDirection d) { - return RayBB[s][d]; + return InFrontBB[opposite_color(c)][square_rank(s)]; } @@ -274,12 +262,11 @@ inline Bitboard squares_between(Square s1, Square s2) { /// squares_in_front_of takes a color and a square as input, and returns a /// bitboard representing all squares along the line in front of the square, -/// from the point of view of the given color. For instance, -/// squares_in_front_of(BLACK, SQ_E4) returns a bitboard with the squares -/// e3, e2 and e1 set. +/// from the point of view of the given color. Definition of the table is: +/// SquaresInFrontOf[c][s] = in_front_bb(c, s) & file_bb(s) inline Bitboard squares_in_front_of(Color c, Square s) { - return in_front_bb(c, s) & file_bb(s); + return SquaresInFrontMask[c][s]; } @@ -287,33 +274,45 @@ inline Bitboard squares_in_front_of(Color c, Square s) { /// behind the square instead of in front of the square. inline Bitboard squares_behind(Color c, Square s) { - return in_front_bb(opposite_color(c), s) & file_bb(s); + return SquaresInFrontMask[opposite_color(c)][s]; } /// passed_pawn_mask takes a color and a square as input, and returns a /// bitboard mask which can be used to test if a pawn of the given color on -/// the given square is a passed pawn. +/// the given square is a passed pawn. Definition of the table is: +/// PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_neighboring_files_bb(s) inline Bitboard passed_pawn_mask(Color c, Square s) { return PassedPawnMask[c][s]; } -/// outpost_mask takes a color and a square as input, and returns a bitboard -/// mask which can be used to test whether a piece on the square can possibly -/// be driven away by an enemy pawn. +/// attack_span_mask takes a color and a square as input, and returns a bitboard +/// representing all squares that can be attacked by a pawn of the given color +/// when it moves along its file starting from the given square. Definition is: +/// AttackSpanMask[c][s] = in_front_bb(c, s) & neighboring_files_bb(s); + +inline Bitboard attack_span_mask(Color c, Square s) { + return AttackSpanMask[c][s]; +} + + +/// squares_aligned returns true if the squares s1, s2 and s3 are aligned +/// either on a straight or on a diagonal line. -inline Bitboard outpost_mask(Color c, Square s) { - return OutpostMask[c][s]; +inline bool squares_aligned(Square s1, Square s2, Square s3) { + return DirectionTable[s1][s2] != DELTA_NONE + && abs(DirectionTable[s1][s2]) == abs(DirectionTable[s2][s3]); } -/// isolated_pawn_mask takes a square as input, and returns a bitboard mask -/// which can be used to test whether a pawn on the given square is isolated. +/// squares_straight_aligned returns true if the squares s1 and s2 are aligned +/// on a straight line, either veritical or horizontal. -inline Bitboard isolated_pawn_mask(Square s) { - return neighboring_files_bb(s); +inline bool squares_straight_aligned(Square s1, Square s2) { + return abs(DirectionTable[s1][s2]) == DELTA_N + || abs(DirectionTable[s1][s2]) == DELTA_E; } @@ -349,7 +348,6 @@ extern Square pop_1st_bit(Bitboard* b); extern void print_bitboard(Bitboard b); extern void init_bitboards(); -extern int bitScanReverse32(uint32_t b); #endif // !defined(BITBOARD_H_INCLUDED)