fixed promotions

src/MoveGeneration.cpp

@@ -68,7 +68,10 @@ typename PromotionGenerator<side>::MoveIterator PromotionGenerator<side>::begin(
 {
     const Board& board = chessGame.getBoard();
     Bitboard pawns = board.getPawns<side>();
-    pawns &= Bitboard(0xFF000000000000FFULL);
+    if (side == WHITE_SIDE)
+        pawns &= Bitboard(0x00FF000000000000ULL);
+    else
+        pawns &= Bitboard(0x000000000000FF00ULL);
 
     return MoveIterator{ chessGame, pawns, PieceType::KNIGHT, -1 };
 }