Remove Some Bitboard Arrays (#1963)

[stockfish] / src / bitboard.cpp

diff --git a/src/bitboard.cpp b/src/bitboard.cpp
index 105d201f1c17de3ca2cfc9a1cad5a2d9aab4efd7..13735e3df9537d9cce6f726b1ccfda909ce45ba3 100644 (file)
--- a/src/bitboard.cpp
+++ b/src/bitboard.cpp
@@ -27,15 +27,10 @@ uint8_t PopCnt16[1 << 16];
 int8_t SquareDistance[SQUARE_NB][SQUARE_NB];
 
 Bitboard SquareBB[SQUARE_NB];
-Bitboard FileBB[FILE_NB];
-Bitboard RankBB[RANK_NB];
 Bitboard ForwardRanksBB[COLOR_NB][RANK_NB];
 Bitboard BetweenBB[SQUARE_NB][SQUARE_NB];
 Bitboard LineBB[SQUARE_NB][SQUARE_NB];
 Bitboard DistanceRingBB[SQUARE_NB][8];
-Bitboard ForwardFileBB[COLOR_NB][SQUARE_NB];
-Bitboard PassedPawnMask[COLOR_NB][SQUARE_NB];
-Bitboard PawnAttackSpan[COLOR_NB][SQUARE_NB];
 Bitboard PseudoAttacks[PIECE_TYPE_NB][SQUARE_NB];
 Bitboard PawnAttacks[COLOR_NB][SQUARE_NB];
 
@@ -90,22 +85,8 @@ void Bitboards::init() {
   for (Square s = SQ_A1; s <= SQ_H8; ++s)
       SquareBB[s] = (1ULL << s);
 
-  for (File f = FILE_A; f <= FILE_H; ++f)
-      FileBB[f] = f > FILE_A ? FileBB[f - 1] << 1 : FileABB;
-
-  for (Rank r = RANK_1; r <= RANK_8; ++r)
-      RankBB[r] = r > RANK_1 ? RankBB[r - 1] << 8 : Rank1BB;
-
   for (Rank r = RANK_1; r < RANK_8; ++r)
-      ForwardRanksBB[WHITE][r] = ~(ForwardRanksBB[BLACK][r + 1] = ForwardRanksBB[BLACK][r] | RankBB[r]);
-
-  for (Color c = WHITE; c <= BLACK; ++c)
-      for (Square s = SQ_A1; s <= SQ_H8; ++s)
-      {
-          ForwardFileBB [c][s] = ForwardRanksBB[c][rank_of(s)] & FileBB[file_of(s)];
-          PawnAttackSpan[c][s] = ForwardRanksBB[c][rank_of(s)] & adjacent_files_bb(file_of(s));
-          PassedPawnMask[c][s] = ForwardFileBB [c][s] | PawnAttackSpan[c][s];
-      }
+      ForwardRanksBB[WHITE][r] = ~(ForwardRanksBB[BLACK][r + 1] = ForwardRanksBB[BLACK][r] | rank_bb(r));
 
   for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1)
       for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2)