X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.h;h=af7b592ad564cb5a3af85ca97173d5259e390484;hp=37585bb19b18e8e25feb54120429b3177caa6da6;hb=7133598a98301cf84857d39194026b876da48b96;hpb=090e49547ecaba8c9ec696d75f2fca3020bb058a

diff --git a/src/bitboard.h b/src/bitboard.h
index 37585bb1..af7b592a 100644
--- a/src/bitboard.h
+++ b/src/bitboard.h
@@ -60,21 +60,21 @@ constexpr Bitboard Rank6BB = Rank1BB << (8 * 5);
 constexpr Bitboard Rank7BB = Rank1BB << (8 * 6);
 constexpr Bitboard Rank8BB = Rank1BB << (8 * 7);
 
-extern int SquareDistance[SQUARE_NB][SQUARE_NB];
+constexpr Bitboard QueenSide   = FileABB | FileBBB | FileCBB | FileDBB;
+constexpr Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB;
+constexpr Bitboard KingSide    = FileEBB | FileFBB | FileGBB | FileHBB;
+constexpr Bitboard Center      = (FileDBB | FileEBB) & (Rank4BB | Rank5BB);
+
+extern uint8_t PopCnt16[1 << 16];
+extern uint8_t SquareDistance[SQUARE_NB][SQUARE_NB];
 
 extern Bitboard SquareBB[SQUARE_NB];
-extern Bitboard FileBB[FILE_NB];
-extern Bitboard RankBB[RANK_NB];
-extern Bitboard AdjacentFilesBB[FILE_NB];
-extern Bitboard ForwardRanksBB[COLOR_NB][RANK_NB];
 extern Bitboard BetweenBB[SQUARE_NB][SQUARE_NB];
 extern Bitboard LineBB[SQUARE_NB][SQUARE_NB];
 extern Bitboard DistanceRingBB[SQUARE_NB][8];
-extern Bitboard ForwardFileBB[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 Bitboard PawnAttacks[COLOR_NB][SQUARE_NB];
+extern Bitboard KingFlank[FILE_NB];
 
 
 /// Magic holds all magic bitboards relevant data for a single square
@@ -136,30 +136,31 @@ constexpr bool more_than_one(Bitboard b) {
 }
 
 inline bool opposite_colors(Square s1, Square s2) {
-  return (bool(DarkSquares & s1) != bool(DarkSquares & s2));
+  return bool(DarkSquares & s1) != bool(DarkSquares & s2);
 }
 
+
 /// 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];
+  return Rank1BB << (8 * r);
 }
 
 inline Bitboard rank_bb(Square s) {
-  return RankBB[rank_of(s)];
+  return rank_bb(rank_of(s));
 }
 
 inline Bitboard file_bb(File f) {
-  return FileBB[f];
+  return FileABB << f;
 }
 
 inline Bitboard file_bb(Square s) {
-  return FileBB[file_of(s)];
+  return file_bb(file_of(s));
 }
 
 
-/// shift() moves a bitboard one step along direction D (mainly for pawns)
+/// shift() moves a bitboard one step along direction D
 
 template<Direction D>
 constexpr Bitboard shift(Bitboard b) {
@@ -171,8 +172,8 @@ constexpr Bitboard shift(Bitboard b) {
 }
 
 
-/// pawn_attacks_bb() returns the pawn attacks for the given color from the
-/// squares in the given bitboard.
+/// pawn_attacks_bb() returns the squares attacked by pawns of the given color
+/// from the squares in the given bitboard.
 
 template<Color C>
 constexpr Bitboard pawn_attacks_bb(Bitboard b) {
@@ -181,11 +182,11 @@ constexpr Bitboard pawn_attacks_bb(Bitboard b) {
 }
 
 
-/// double_pawn_attacks_bb() returns the pawn attacks for the given color
-/// from the squares in the given bitboard.
+/// pawn_double_attacks_bb() returns the squares doubly attacked by pawns of the
+/// given color from the squares in the given bitboard.
 
 template<Color C>
-constexpr Bitboard double_pawn_attacks_bb(Bitboard b) {
+constexpr Bitboard pawn_double_attacks_bb(Bitboard b) {
   return C == WHITE ? shift<NORTH_WEST>(b) & shift<NORTH_EAST>(b)
                     : shift<SOUTH_WEST>(b) & shift<SOUTH_EAST>(b);
 }
@@ -195,54 +196,52 @@ constexpr Bitboard double_pawn_attacks_bb(Bitboard b) {
 /// adjacent files of the given one.
 
 inline Bitboard adjacent_files_bb(File f) {
-  return AdjacentFilesBB[f];
+  return shift<EAST>(file_bb(f)) | shift<WEST>(file_bb(f));
 }
 
 
 /// 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.
+/// 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_ranks_bb() returns a bitboard representing the squares on all the ranks
+/// forward_ranks_bb() returns a bitboard representing the squares on the ranks
 /// in front of the given one, from the point of view of the given color. For instance,
 /// forward_ranks_bb(BLACK, SQ_D3) will return the 16 squares on ranks 1 and 2.
 
 inline Bitboard forward_ranks_bb(Color c, Square s) {
-  return ForwardRanksBB[c][rank_of(s)];
+  return c == WHITE ? ~Rank1BB << 8 * (rank_of(s) - RANK_1)
+                    : ~Rank8BB >> 8 * (RANK_8 - rank_of(s));
 }
 
 
-/// forward_file_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:
-///      ForwardFileBB[c][s] = forward_ranks_bb(c, s) & file_bb(s)
+/// forward_file_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.
 
 inline Bitboard forward_file_bb(Color c, Square s) {
-  return ForwardFileBB[c][s];
+  return forward_ranks_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] = forward_ranks_bb(c, s) & adjacent_files_bb(file_of(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.
 
 inline Bitboard pawn_attack_span(Color c, Square s) {
-  return PawnAttackSpan[c][s];
+  return forward_ranks_bb(c, s) & adjacent_files_bb(file_of(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_file_bb(c, s)
+/// passed_pawn_span() returns a bitboard which can be used to test if a pawn of
+/// the given color and on the given square is a passed pawn.
 
-inline Bitboard passed_pawn_mask(Color c, Square s) {
-  return PassedPawnMask[c][s];
+inline Bitboard passed_pawn_span(Color c, Square s) {
+  return forward_ranks_bb(c, s) & (adjacent_files_bb(file_of(s)) | file_bb(s));
 }
 
 
@@ -257,7 +256,7 @@ inline bool aligned(Square s1, Square s2, Square s3) {
 /// 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.
 
-template<typename T> inline int distance(T x, T y) { return x < y ? y - x : x - y; }
+template<typename T> inline int distance(T x, T y) { return std::abs(x - y); }
 template<> inline int distance<Square>(Square x, Square y) { return SquareDistance[x][y]; }
 
 template<typename T1, typename T2> inline int distance(T2 x, T2 y);
@@ -295,7 +294,6 @@ inline int popcount(Bitboard b) {
 
 #ifndef USE_POPCNT
 
-  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]];