Revert "Replace aligned() function with line_bb() and simplify king p…

…iece detection" (#5915) closes #5915 No functional change Co-authored-by: Robert Nürnberg <[email protected]>
official-stockfish · Feb 28, 2025 · f3bfce3 · f3bfce3
1 parent 5c617e5
commit f3bfce3
Showing 1 changed file with 3 additions and 3 deletions.
diff --git a/src/position.cpp b/src/position.cpp
@@ -560,7 +560,7 @@ bool Position::legal(Move m) const {
 
     // A non-king move is legal if and only if it is not pinned or it
     // is moving along the ray towards or away from the king.
-    return !(blockers_for_king(us) & from) || line_bb(from, to) & pieces(us, KING);
+    return !(blockers_for_king(us) & from) || aligned(from, to, square<KING>(us));
 }
 
 
@@ -648,15 +648,15 @@ bool Position::gives_check(Move m) const {
 
     // Is there a discovered check?
     if (blockers_for_king(~sideToMove) & from)
-        return !(line_bb(from, to) & pieces(~sideToMove, KING) || m.type_of() == CASTLING);
+        return !aligned(from, to, square<KING>(~sideToMove)) || m.type_of() == CASTLING;
 
     switch (m.type_of())
     {
     case NORMAL :
         return false;
 
     case PROMOTION :
-        return attacks_bb(m.promotion_type(), to, pieces() ^ from) & pieces(~sideToMove, KING);
+        return attacks_bb(m.promotion_type(), to, pieces() ^ from) & square<KING>(~sideToMove);
 
     // En passant capture with check? We have already handled the case of direct
     // checks and ordinary discovered check, so the only case we need to handle