X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;ds=inline;f=src%2Fbitboard.h;h=aa4e17119c1b5f7e81c56631641e8916c369d2d5;hb=8d16111ffde1689d48d47ec379ba91613213183c;hp=cc039397e3330728022f22c2905891a20849a343;hpb=2f47844c7cb34c7de5b5d41cda10b7d8736a20bc;p=stockfish
diff --git a/src/bitboard.h b/src/bitboard.h
index cc039397..aa4e1711 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) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2015 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
@@ -18,42 +18,72 @@
along with this program. If not, see .
*/
-#if !defined(BITBOARD_H_INCLUDED)
+#ifndef BITBOARD_H_INCLUDED
#define BITBOARD_H_INCLUDED
+#include
+
#include "types.h"
-namespace Bitboards {
+namespace Bitbases {
-extern void init();
-extern void print(Bitboard b);
+void init();
+bool probe(Square wksq, Square wpsq, Square bksq, Color us);
}
-CACHE_LINE_ALIGNMENT
+namespace Bitboards {
-extern Bitboard RMasks[64];
-extern Bitboard RMagics[64];
-extern Bitboard* RAttacks[64];
-extern unsigned RShifts[64];
+void init();
+const std::string pretty(Bitboard b);
-extern Bitboard BMasks[64];
-extern Bitboard BMagics[64];
-extern Bitboard* BAttacks[64];
-extern unsigned BShifts[64];
+}
-extern Bitboard SquareBB[64];
-extern Bitboard FileBB[8];
-extern Bitboard RankBB[8];
-extern Bitboard AdjacentFilesBB[8];
-extern Bitboard ThisAndAdjacentFilesBB[8];
-extern Bitboard InFrontBB[2][8];
-extern Bitboard StepAttacksBB[16][64];
-extern Bitboard BetweenBB[64][64];
-extern Bitboard ForwardBB[2][64];
-extern Bitboard PassedPawnMask[2][64];
-extern Bitboard AttackSpanMask[2][64];
-extern Bitboard PseudoAttacks[6][64];
+const Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL;
+
+const Bitboard FileABB = 0x0101010101010101ULL;
+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 int SquareDistance[SQUARE_NB][SQUARE_NB];
+
+extern Bitboard RookMasks [SQUARE_NB];
+extern Bitboard RookMagics [SQUARE_NB];
+extern Bitboard* RookAttacks[SQUARE_NB];
+extern unsigned RookShifts [SQUARE_NB];
+
+extern Bitboard BishopMasks [SQUARE_NB];
+extern Bitboard BishopMagics [SQUARE_NB];
+extern Bitboard* BishopAttacks[SQUARE_NB];
+extern unsigned BishopShifts [SQUARE_NB];
+
+extern Bitboard SquareBB[SQUARE_NB];
+extern Bitboard FileBB[FILE_NB];
+extern Bitboard RankBB[RANK_NB];
+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 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];
/// Overloads of bitwise operators between a Bitboard and a Square for testing
@@ -63,14 +93,6 @@ 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];
}
@@ -79,16 +101,21 @@ inline Bitboard operator^(Bitboard b, Square s) {
return b ^ SquareBB[s];
}
+inline Bitboard& operator|=(Bitboard& b, Square s) {
+ return b |= SquareBB[s];
+}
-/// more_than_one() returns true if in 'b' there is more than one bit set
+inline Bitboard& operator^=(Bitboard& b, Square s) {
+ return b ^= SquareBB[s];
+}
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];
@@ -107,165 +134,207 @@ 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
+
+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;
+}
+
+
+/// adjacent_files_bb() returns a bitboard representing all the squares on the
+/// adjacent files of the given one.
inline Bitboard adjacent_files_bb(File f) {
return AdjacentFilesBB[f];
}
-/// this_and_adjacent_files_bb takes a file as input and returns a bitboard
-/// representing all squares on the given and adjacent files.
+/// 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 this_and_adjacent_files_bb(File f) {
- return ThisAndAdjacentFilesBB[f];
+inline Bitboard between_bb(Square s1, Square s2) {
+ return BetweenBB[s1][s2];
}
-/// in_front_bb() takes a color and a rank or square as input, and returns a
-/// bitboard representing all the squares on all ranks in front of the rank
-/// (or square), from the given color's point of view. For instance,
-/// in_front_bb(WHITE, RANK_5) will give all squares on ranks 6, 7 and 8, while
-/// in_front_bb(BLACK, SQ_D3) will give all squares on ranks 1 and 2.
+/// 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];
}
-inline Bitboard in_front_bb(Color c, Square s) {
- return InFrontBB[c][rank_of(s)];
-}
-
-/// 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.
+/// 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 between_bb(Square s1, Square s2) {
- return BetweenBB[s1][s2];
+inline Bitboard forward_bb(Color c, Square s) {
+ return ForwardBB[c][s];
}
-/// 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)
+/// 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 forward_bb(Color c, Square s) {
- return ForwardBB[c][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] = in_front_bb(c, s) & this_and_adjacent_files_bb(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];
}
-/// 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) & adjacent_files_bb(s);
+/// squares_of_color() returns a bitboard representing all the squares of the
+/// same color of the given one.
-inline Bitboard attack_span_mask(Color c, Square s) {
- return AttackSpanMask[c][s];
+inline Bitboard squares_of_color(Square s) {
+ return DarkSquares & s ? DarkSquares : ~DarkSquares;
}
-/// squares_aligned returns true if the squares s1, s2 and s3 are aligned
-/// either on a straight or on a diagonal line.
+/// aligned() returns true if the squares s1, s2 and s3 are aligned either on a
+/// straight or on a diagonal line.
-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]);
+inline bool aligned(Square s1, Square s2, Square s3) {
+ return LineBB[s1][s2] & s3;
}
-/// same_color_squares() returns a bitboard representing all squares with
-/// the same color of the given square.
+/// 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 Bitboard same_color_squares(Square s) {
- return Bitboard(0xAA55AA55AA55AA55ULL) & s ? 0xAA55AA55AA55AA55ULL
- : ~0xAA55AA55AA55AA55ULL;
-}
+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) {
+FORCE_INLINE unsigned magic_index(Square s, Bitboard occupied) {
- Bitboard* const Masks = Pt == ROOK ? RMasks : BMasks;
- Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics;
- unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts;
+ Bitboard* const Masks = Pt == ROOK ? RookMasks : BishopMasks;
+ Bitboard* const Magics = Pt == ROOK ? RookMagics : BishopMagics;
+ unsigned* const Shifts = Pt == ROOK ? RookShifts : BishopShifts;
+
+ 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) {
+ 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];
+ }
}
-/// first_1() finds the least significant nonzero bit in a nonzero bitboard.
-/// pop_1st_bit() finds and clears the least significant nonzero bit in a
-/// nonzero bitboard.
+/// lsb() and msb() return the least/most significant bit in a non-zero bitboard
+
+#ifdef USE_BSFQ
+
+# if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
-#if defined(USE_BSFQ)
+FORCE_INLINE Square lsb(Bitboard b) {
+ unsigned long idx;
+ _BitScanForward64(&idx, b);
+ return (Square) idx;
+}
+
+FORCE_INLINE Square msb(Bitboard b) {
+ unsigned long idx;
+ _BitScanReverse64(&idx, b);
+ return (Square) idx;
+}
-#if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
+# elif defined(__arm__)
-FORCE_INLINE Square first_1(Bitboard b) {
- unsigned long index;
- _BitScanForward64(&index, b);
- return (Square) index;
+FORCE_INLINE int lsb32(uint32_t v) {
+ __asm__("rbit %0, %1" : "=r"(v) : "r"(v));
+ return __builtin_clz(v);
}
-FORCE_INLINE Square last_1(Bitboard b) {
- unsigned long index;
- _BitScanReverse64(&index, b);
- return (Square) index;
+FORCE_INLINE Square msb(Bitboard b) {
+ return (Square) (63 - __builtin_clzll(b));
}
-#else
-FORCE_INLINE Square first_1(Bitboard b) { // Assembly code by Heinz van Saanen
- Bitboard dummy;
- __asm__("bsfq %1, %0": "=r"(dummy): "rm"(b) );
- return (Square) dummy;
+FORCE_INLINE Square lsb(Bitboard b) {
+ return (Square) (uint32_t(b) ? lsb32(uint32_t(b)) : 32 + lsb32(uint32_t(b >> 32)));
}
-FORCE_INLINE Square last_1(Bitboard b) {
- Bitboard dummy;
- __asm__("bsrq %1, %0": "=r"(dummy): "rm"(b) );
- return (Square) dummy;
+# else // Assumed gcc or compatible compiler
+
+FORCE_INLINE Square lsb(Bitboard b) { // Assembly code by Heinz van Saanen
+ Bitboard idx;
+ __asm__("bsfq %1, %0": "=r"(idx): "rm"(b) );
+ return (Square) idx;
}
+
+FORCE_INLINE Square msb(Bitboard b) {
+ Bitboard idx;
+ __asm__("bsrq %1, %0": "=r"(idx): "rm"(b) );
+ return (Square) idx;
+}
+
+# endif
+
+#else // ifdef(USE_BSFQ)
+
+Square lsb(Bitboard b);
+Square msb(Bitboard b);
+
#endif
-FORCE_INLINE Square pop_1st_bit(Bitboard* b) {
- const Square s = first_1(*b);
- *b &= ~(1ULL<