X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.h;h=390966e3494273969bdb53a50c6953a6c9782611;hp=3afbeedfbab42ee086000de51a4964350b34bea5;hb=5e4cd3fc0d4b88eeb09ae458b9cb9f73db8c4ae7;hpb=14f47c8ac6a77b9638008a9b61009dd6852be4d6 diff --git a/src/bitboard.h b/src/bitboard.h index 3afbeedf..390966e3 100644 --- a/src/bitboard.h +++ b/src/bitboard.h @@ -1,14 +1,14 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2015-2016 Marco Costalba, Joona Kiiski, Gary Linscott, 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 the Free Software Foundation, either version 3 of the License, or (at your option) any later version. - Stockfish is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the @@ -21,22 +21,26 @@ #ifndef BITBOARD_H_INCLUDED #define BITBOARD_H_INCLUDED +#include + #include "types.h" -namespace Bitboards { +namespace Bitbases { void init(); -void print(Bitboard b); +bool probe(Square wksq, Square wpsq, Square bksq, Color us); } -namespace Bitbases { +namespace Bitboards { -void init_kpk(); -bool probe_kpk(Square wksq, Square wpsq, Square bksq, Color us); +void init(); +const std::string pretty(Bitboard b); } +const Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL; + const Bitboard FileABB = 0x0101010101010101ULL; const Bitboard FileBBB = FileABB << 1; const Bitboard FileCBB = FileABB << 2; @@ -55,17 +59,7 @@ const Bitboard Rank6BB = Rank1BB << (8 * 5); const Bitboard Rank7BB = Rank1BB << (8 * 6); const Bitboard Rank8BB = Rank1BB << (8 * 7); -CACHE_LINE_ALIGNMENT - -extern Bitboard RMasks[SQUARE_NB]; -extern Bitboard RMagics[SQUARE_NB]; -extern Bitboard* RAttacks[SQUARE_NB]; -extern unsigned RShifts[SQUARE_NB]; - -extern Bitboard BMasks[SQUARE_NB]; -extern Bitboard BMagics[SQUARE_NB]; -extern Bitboard* BAttacks[SQUARE_NB]; -extern unsigned BShifts[SQUARE_NB]; +extern int SquareDistance[SQUARE_NB][SQUARE_NB]; extern Bitboard SquareBB[SQUARE_NB]; extern Bitboard FileBB[FILE_NB]; @@ -74,15 +68,13 @@ extern Bitboard AdjacentFilesBB[FILE_NB]; extern Bitboard InFrontBB[COLOR_NB][RANK_NB]; extern Bitboard StepAttacksBB[PIECE_NB][SQUARE_NB]; extern Bitboard BetweenBB[SQUARE_NB][SQUARE_NB]; -extern Bitboard DistanceRingsBB[SQUARE_NB][8]; +extern Bitboard LineBB[SQUARE_NB][SQUARE_NB]; +extern Bitboard DistanceRingBB[SQUARE_NB][8]; extern Bitboard ForwardBB[COLOR_NB][SQUARE_NB]; extern Bitboard PassedPawnMask[COLOR_NB][SQUARE_NB]; extern Bitboard PawnAttackSpan[COLOR_NB][SQUARE_NB]; extern Bitboard PseudoAttacks[PIECE_TYPE_NB][SQUARE_NB]; -extern int SquareDistance[SQUARE_NB][SQUARE_NB]; - -const Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL; /// Overloads of bitwise operators between a Bitboard and a Square for testing /// whether a given bit is set in a bitboard, and for setting and clearing bits. @@ -91,14 +83,6 @@ inline Bitboard operator&(Bitboard b, Square s) { return b & SquareBB[s]; } -inline Bitboard& operator|=(Bitboard& b, Square s) { - return b |= SquareBB[s]; -} - -inline Bitboard& operator^=(Bitboard& b, Square s) { - return b ^= SquareBB[s]; -} - inline Bitboard operator|(Bitboard b, Square s) { return b | SquareBB[s]; } @@ -107,37 +91,21 @@ inline Bitboard operator^(Bitboard b, Square s) { return b ^ SquareBB[s]; } -inline bool more_than_one(Bitboard b) { - return b & (b - 1); -} - -inline int square_distance(Square s1, Square s2) { - return SquareDistance[s1][s2]; -} - -inline int file_distance(Square s1, Square s2) { - return abs(file_of(s1) - file_of(s2)); +inline Bitboard& operator|=(Bitboard& b, Square s) { + return b |= SquareBB[s]; } -inline int rank_distance(Square s1, Square s2) { - return abs(rank_of(s1) - rank_of(s2)); +inline Bitboard& operator^=(Bitboard& b, Square s) { + return b ^= SquareBB[s]; } - -/// shift_bb() moves bitboard one step along direction Delta. Mainly for pawns. - -template -inline Bitboard shift_bb(Bitboard b) { - - return Delta == DELTA_N ? b << 8 : Delta == DELTA_S ? b >> 8 - : Delta == DELTA_NE ? (b & ~FileHBB) << 9 : Delta == DELTA_SE ? (b & ~FileHBB) >> 7 - : Delta == DELTA_NW ? (b & ~FileABB) << 7 : Delta == DELTA_SW ? (b & ~FileABB) >> 9 - : 0; +inline bool more_than_one(Bitboard b) { + return b & (b - 1); } -/// 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. +/// rank_bb() and file_bb() return a bitboard representing all the squares on +/// the given file or rank. inline Bitboard rank_bb(Rank r) { return RankBB[r]; @@ -156,170 +124,212 @@ inline Bitboard file_bb(Square s) { } -/// adjacent_files_bb() takes a file as input and returns a bitboard representing -/// all squares on the adjacent files. +/// shift_bb() moves a bitboard one step along direction Delta. Mainly for pawns -inline Bitboard adjacent_files_bb(File f) { - return AdjacentFilesBB[f]; +template +inline Bitboard shift_bb(Bitboard b) { + return Delta == DELTA_N ? b << 8 : Delta == DELTA_S ? b >> 8 + : Delta == DELTA_NE ? (b & ~FileHBB) << 9 : Delta == DELTA_SE ? (b & ~FileHBB) >> 7 + : Delta == DELTA_NW ? (b & ~FileABB) << 7 : Delta == DELTA_SW ? (b & ~FileABB) >> 9 + : 0; } -/// in_front_bb() takes a color and a rank as input, and returns a bitboard -/// representing all the squares on all ranks in front of the rank, from the -/// given color's point of view. For instance, in_front_bb(BLACK, RANK_3) will -/// give all squares on ranks 1 and 2. +/// adjacent_files_bb() returns a bitboard representing all the squares on the +/// adjacent files of the given one. -inline Bitboard in_front_bb(Color c, Rank r) { - return InFrontBB[c][r]; +inline Bitboard adjacent_files_bb(File f) { + return AdjacentFilesBB[f]; } -/// between_bb() returns a bitboard representing all squares between two squares. -/// For instance, between_bb(SQ_C4, SQ_F7) returns a bitboard with the bits for -/// square d5 and e6 set. If s1 and s2 are not on the same line, file or diagonal, -/// 0 is returned. +/// between_bb() returns a bitboard representing all the squares between the two +/// given ones. For instance, between_bb(SQ_C4, SQ_F7) returns a bitboard with +/// the bits for square d5 and e6 set. If s1 and s2 are not on the same rank, file +/// or diagonal, 0 is returned. inline Bitboard between_bb(Square s1, Square s2) { return BetweenBB[s1][s2]; } -/// forward_bb() 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. Definition of the table is: -/// ForwardBB[c][s] = in_front_bb(c, s) & file_bb(s) +/// in_front_bb() returns a bitboard representing all the squares on all the ranks +/// in front of the given one, from the point of view of the given color. For +/// instance, in_front_bb(BLACK, RANK_3) will return the squares on ranks 1 and 2. + +inline Bitboard in_front_bb(Color c, Rank r) { + return InFrontBB[c][r]; +} + + +/// forward_bb() returns a bitboard representing all the squares along the line +/// in front of the given one, from the point of view of the given color: +/// ForwardBB[c][s] = in_front_bb(c, s) & file_bb(s) inline Bitboard forward_bb(Color c, Square s) { return ForwardBB[c][s]; } -/// pawn_attack_span() 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: -/// PawnAttackSpan[c][s] = in_front_bb(c, s) & adjacent_files_bb(s); +/// pawn_attack_span() returns a bitboard representing all the squares that can be +/// attacked by a pawn of the given color when it moves along its file, starting +/// from the given square: +/// PawnAttackSpan[c][s] = in_front_bb(c, s) & adjacent_files_bb(s); inline Bitboard pawn_attack_span(Color c, Square s) { return PawnAttackSpan[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. Definition of the table is: -/// PassedPawnMask[c][s] = pawn_attack_span(c, s) | forward_bb(c, s) +/// passed_pawn_mask() returns a bitboard mask which can be used to test if a +/// pawn of the given color and on the given square is a passed pawn: +/// PassedPawnMask[c][s] = pawn_attack_span(c, s) | forward_bb(c, s) inline Bitboard passed_pawn_mask(Color c, Square s) { return PassedPawnMask[c][s]; } -/// squares_of_color() returns a bitboard representing all squares with the same -/// color of the given square. +/// aligned() returns true if the squares s1, s2 and s3 are aligned either on a +/// straight or on a diagonal line. -inline Bitboard squares_of_color(Square s) { - return DarkSquares & s ? DarkSquares : ~DarkSquares; +inline bool aligned(Square s1, Square s2, Square s3) { + return LineBB[s1][s2] & s3; } -/// squares_aligned() returns true if the squares s1, s2 and s3 are aligned -/// either on a straight or on a diagonal line. +/// distance() functions return the distance between x and y, defined as the +/// number of steps for a king in x to reach y. Works with squares, ranks, files. -inline bool squares_aligned(Square s1, Square s2, Square s3) { - return (BetweenBB[s1][s2] | BetweenBB[s1][s3] | BetweenBB[s2][s3]) - & ( SquareBB[s1] | SquareBB[s2] | SquareBB[s3]); -} +template inline int distance(T x, T y) { return x < y ? y - x : x - y; } +template<> inline int distance(Square x, Square y) { return SquareDistance[x][y]; } + +template inline int distance(T2 x, T2 y); +template<> inline int distance(Square x, Square y) { return distance(file_of(x), file_of(y)); } +template<> inline int distance(Square x, Square y) { return distance(rank_of(x), rank_of(y)); } -/// Functions for computing sliding attack bitboards. Function attacks_bb() takes -/// a square and a bitboard of occupied squares as input, and returns a bitboard -/// representing all squares attacked by Pt (bishop or rook) on the given square. +/// attacks_bb() returns a bitboard representing all the squares attacked by a +/// piece of type Pt (bishop or rook) placed on 's'. The helper magic_index() +/// looks up the index using the 'magic bitboards' approach. template -FORCE_INLINE unsigned magic_index(Square s, Bitboard occ) { +inline unsigned magic_index(Square s, Bitboard occupied) { + + extern Bitboard RookMasks[SQUARE_NB]; + extern Bitboard RookMagics[SQUARE_NB]; + extern unsigned RookShifts[SQUARE_NB]; + extern Bitboard BishopMasks[SQUARE_NB]; + extern Bitboard BishopMagics[SQUARE_NB]; + extern unsigned BishopShifts[SQUARE_NB]; + + Bitboard* const Masks = Pt == ROOK ? RookMasks : BishopMasks; + Bitboard* const Magics = Pt == ROOK ? RookMagics : BishopMagics; + unsigned* const Shifts = Pt == ROOK ? RookShifts : BishopShifts; - Bitboard* const Masks = Pt == ROOK ? RMasks : BMasks; - Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics; - unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts; + if (HasPext) + return unsigned(pext(occupied, Masks[s])); if (Is64Bit) - return unsigned(((occ & Masks[s]) * Magics[s]) >> Shifts[s]); + return unsigned(((occupied & Masks[s]) * Magics[s]) >> Shifts[s]); - unsigned lo = unsigned(occ) & unsigned(Masks[s]); - unsigned hi = unsigned(occ >> 32) & unsigned(Masks[s] >> 32); + unsigned lo = unsigned(occupied) & unsigned(Masks[s]); + unsigned hi = unsigned(occupied >> 32) & unsigned(Masks[s] >> 32); return (lo * unsigned(Magics[s]) ^ hi * unsigned(Magics[s] >> 32)) >> Shifts[s]; } template -inline Bitboard attacks_bb(Square s, Bitboard occ) { - return (Pt == ROOK ? RAttacks : BAttacks)[s][magic_index(s, occ)]; +inline Bitboard attacks_bb(Square s, Bitboard occupied) { + + extern Bitboard* RookAttacks[SQUARE_NB]; + extern Bitboard* BishopAttacks[SQUARE_NB]; + + return (Pt == ROOK ? RookAttacks : BishopAttacks)[s][magic_index(s, occupied)]; } +inline Bitboard attacks_bb(Piece pc, Square s, Bitboard occupied) { + + switch (type_of(pc)) + { + case BISHOP: return attacks_bb(s, occupied); + case ROOK : return attacks_bb(s, occupied); + case QUEEN : return attacks_bb(s, occupied) | attacks_bb(s, occupied); + default : return StepAttacksBB[pc][s]; + } +} -/// lsb()/msb() finds the least/most significant bit in a nonzero bitboard. -/// pop_lsb() finds and clears the least significant bit in a nonzero bitboard. -#ifdef USE_BSFQ +/// popcount() counts the number of non-zero bits in a bitboard -# if defined(_MSC_VER) && !defined(__INTEL_COMPILER) +inline int popcount(Bitboard b) { -FORCE_INLINE Square lsb(Bitboard b) { - unsigned long index; - _BitScanForward64(&index, b); - return (Square) index; -} +#ifndef USE_POPCNT -FORCE_INLINE Square msb(Bitboard b) { - unsigned long index; - _BitScanReverse64(&index, b); - return (Square) index; -} + extern uint8_t PopCnt16[1 << 16]; + union { Bitboard bb; uint16_t u[4]; } v = { b }; + return PopCnt16[v.u[0]] + PopCnt16[v.u[1]] + PopCnt16[v.u[2]] + PopCnt16[v.u[3]]; -# elif defined(__arm__) +#elif defined(_MSC_VER) || defined(__INTEL_COMPILER) -FORCE_INLINE int lsb32(uint32_t v) { - __asm__("rbit %0, %1" : "=r"(v) : "r"(v)); - return __builtin_clz(v); + return (int)_mm_popcnt_u64(b); + +#else // Assumed gcc or compatible compiler + + return __builtin_popcountll(b); + +#endif } -FORCE_INLINE Square msb(Bitboard b) { - return (Square) (63 - __builtin_clzll(b)); + +/// lsb() and msb() return the least/most significant bit in a non-zero bitboard + +#if defined(__GNUC__) + +inline Square lsb(Bitboard b) { + assert(b); + return Square(__builtin_ctzll(b)); } -FORCE_INLINE Square lsb(Bitboard b) { - return (Square) (uint32_t(b) ? lsb32(uint32_t(b)) : 32 + lsb32(uint32_t(b >> 32))); +inline Square msb(Bitboard b) { + assert(b); + return Square(63 - __builtin_clzll(b)); } -# else +#elif defined(_WIN64) && defined(_MSC_VER) -FORCE_INLINE Square lsb(Bitboard b) { // Assembly code by Heinz van Saanen - Bitboard index; - __asm__("bsfq %1, %0": "=r"(index): "rm"(b) ); - return (Square) index; +inline Square lsb(Bitboard b) { + assert(b); + unsigned long idx; + _BitScanForward64(&idx, b); + return (Square) idx; } -FORCE_INLINE Square msb(Bitboard b) { - Bitboard index; - __asm__("bsrq %1, %0": "=r"(index): "rm"(b) ); - return (Square) index; +inline Square msb(Bitboard b) { + assert(b); + unsigned long idx; + _BitScanReverse64(&idx, b); + return (Square) idx; } -# endif +#else + +#define NO_BSF // Fallback on software implementation for other cases + +Square lsb(Bitboard b); +Square msb(Bitboard b); + +#endif -FORCE_INLINE Square pop_lsb(Bitboard* b) { + +/// pop_lsb() finds and clears the least significant bit in a non-zero bitboard + +inline Square pop_lsb(Bitboard* b) { const Square s = lsb(*b); *b &= *b - 1; return s; } -#else // if defined(USE_BSFQ) - -extern Square msb(Bitboard b); -extern Square lsb(Bitboard b); -extern Square pop_lsb(Bitboard* b); - -#endif -/// frontmost_sq() and backmost_sq() find the square corresponding to the +/// frontmost_sq() and backmost_sq() return the square corresponding to the /// most/least advanced bit relative to the given color. inline Square frontmost_sq(Color c, Bitboard b) { return c == WHITE ? msb(b) : lsb(b); }