- (unless (block-delete-p block)
- (setf (block-delete-p block) t)
- (setf (component-reanalyze (block-component block)) t)
- (dolist (pred (block-pred block))
- (mark-for-deletion pred)))
+ (let* ((component (block-component block))
+ (head (component-head component)))
+ (labels ((helper (block)
+ (setf (block-delete-p block) t)
+ (dolist (pred (block-pred block))
+ (unless (or (block-delete-p pred)
+ (eq pred head))
+ (helper pred)))))
+ (unless (block-delete-p block)
+ (helper block)
+ (setf (component-reanalyze component) t))))