WebSVN – Games.Chess Giants – Diff – /engine-stockfish/bitboard.h

   Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
-  Copyright (C) 2015-2016 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+  Copyright (C) 2015-2018 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.
 void init();
 const std::string pretty(Bitboard b);
+}
+const Bitboard AllSquares = ~Bitboard(0);
 const Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL;
 const Bitboard FileABB = 0x0101010101010101ULL;
 const Bitboard FileBBB = FileABB << 1;
 const Bitboard FileCBB = FileABB << 2;
 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 ForwardRanksBB[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 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];
+/// Magic holds all magic bitboards relevant data for a single square
+struct Magic {
+  Bitboard  mask;
+  Bitboard  magic;
+  Bitboard* attacks;
+  unsigned  shift;
+  // Compute the attack's index using the 'magic bitboards' approach
+  unsigned index(Bitboard occupied) const {
+    if (HasPext)
+        return unsigned(pext(occupied, mask));
+    if (Is64Bit)
+        return unsigned(((occupied & mask) * magic) >> shift);
+    unsigned lo = unsigned(occupied) & unsigned(mask);
+    unsigned hi = unsigned(occupied >> 32) & unsigned(mask >> 32);
+    return (lo * unsigned(magic) ^ hi * unsigned(magic >> 32)) >> shift;
+  }
+};
+extern Magic RookMagics[SQUARE_NB];
+extern Magic BishopMagics[SQUARE_NB];
 /// 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.
 inline Bitboard& operator^=(Bitboard& b, Square s) {
   return b ^= SquareBB[s];
+}
-inline bool more_than_one(Bitboard b) {
+constexpr bool more_than_one(Bitboard b) {
   return b & (b - 1);
+}
 /// rank_bb() and file_bb() return a bitboard representing all the squares on
 /// the given file or rank.
 inline Bitboard rank_bb(Rank r) {
+}
 /// shift() moves a bitboard one step along direction D. Mainly for pawns
-template<Square D>
+template<Direction D>
-inline Bitboard shift(Bitboard b) {
+constexpr Bitboard shift(Bitboard b) {
   return  D == NORTH      ?  b             << 8 : D == SOUTH      ?  b             >> 8
         : D == NORTH_EAST ? (b & ~FileHBB) << 9 : D == SOUTH_EAST ? (b & ~FileHBB) >> 7
         : D == NORTH_WEST ? (b & ~FileABB) << 7 : D == SOUTH_WEST ? (b & ~FileABB) >> 9
         : 0;
+}
 inline Bitboard between_bb(Square s1, Square s2) {
   return BetweenBB[s1][s2];
+}
-/// in_front_bb() returns a bitboard representing all the squares on all the ranks
+/// forward_ranks_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.
+/// instance, forward_ranks_bb(BLACK, SQ_D3) will return the 16 squares on ranks 1 and 2.
-inline Bitboard in_front_bb(Color c, Rank r) {
+inline Bitboard forward_ranks_bb(Color c, Square s) {
-  return InFrontBB[c][r];
+  return ForwardRanksBB[c][rank_of(s)];
+}
-/// forward_bb() returns a bitboard representing all the squares along the line
+/// 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:
-///        ForwardBB[c][s] = in_front_bb(c, s) & file_bb(s)
+///      ForwardFileBB[c][s] = forward_ranks_bb(c, s) & file_bb(s)
-inline Bitboard forward_bb(Color c, Square s) {
+inline Bitboard forward_file_bb(Color c, Square s) {
-  return ForwardBB[c][s];
+  return ForwardFileBB[c][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);
+///      PawnAttackSpan[c][s] = forward_ranks_bb(c, s) & adjacent_files_bb(file_of(s));
 inline Bitboard pawn_attack_span(Color c, Square s) {
   return PawnAttackSpan[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)
+///      PassedPawnMask[c][s] = pawn_attack_span(c, s) | forward_file_bb(c, s)
 inline Bitboard passed_pawn_mask(Color c, Square s) {
   return PassedPawnMask[c][s];
+}
 template<> inline int distance<File>(Square x, Square y) { return distance(file_of(x), file_of(y)); }
 template<> inline int distance<Rank>(Square x, Square y) { return distance(rank_of(x), rank_of(y)); }
 /// 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()
+/// piece of type Pt (bishop or rook) placed on 's'.
-/// looks up the index using the 'magic bitboards' approach.
-template<PieceType Pt>
-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;
-  if (HasPext)
-      return unsigned(pext(occupied, Masks[s]));
-  if (Is64Bit)
-      return unsigned(((occupied & Masks[s]) * Magics[s]) >> Shifts[s]);
-  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<PieceType Pt>
 inline Bitboard attacks_bb(Square s, Bitboard occupied) {
-  extern Bitboard* RookAttacks[SQUARE_NB];
+  const Magic& m = Pt == ROOK ? RookMagics[s] : BishopMagics[s];
-  extern Bitboard* BishopAttacks[SQUARE_NB];
+  return m.attacks[m.index(occupied)];
+}
-  return (Pt == ROOK ? RookAttacks : BishopAttacks)[s][magic_index<Pt>(s, occupied)];
+inline Bitboard attacks_bb(PieceType pt, Square s, Bitboard occupied) {
-}
-inline Bitboard attacks_bb(Piece pc, Square s, Bitboard occupied) {
+  assert(pt != PAWN);
-  switch (type_of(pc))
+  switch (pt)
+  {
   case BISHOP: return attacks_bb<BISHOP>(s, occupied);
-  case ROOK  : return attacks_bb<ROOK>(s, occupied);
+  case ROOK  : return attacks_bb<  ROOK>(s, occupied);
   case QUEEN : return attacks_bb<BISHOP>(s, occupied) | attacks_bb<ROOK>(s, occupied);
-  default    : return StepAttacksBB[pc][s];
+  default    : return PseudoAttacks[pt][s];
+  }
+}
 /// popcount() counts the number of non-zero bits in a bitboard
   return Square(__builtin_ctzll(b));
+}
 inline Square msb(Bitboard b) {
   assert(b);
-  return Square(63 - __builtin_clzll(b));
+  return Square(63 ^ __builtin_clzll(b));
+}
 #elif defined(_WIN64) && defined(_MSC_VER)
 inline Square lsb(Bitboard b) {

Subversion Repositories Games.Chess Giants

Games.Chess Giants/engine-stockfish/bitboard.h – Rev 154 → 169