7 uses of MENU_VISIBLE_IN_TREE in Drupal 4

menu_disable_confirm_submit in modules/menu.module

menu_edit_item_form in modules/menu.module

Present the menu item editing form.

menu_overview_tree_rows in modules/menu.module

menu_parent_options in modules/menu.module

Return a list of menu items that are valid possible parents for the given menu item. The list excludes the given item and its children.

_menu_append_contextual_items in includes/menu.inc

Account for menu items that are only defined at certain paths, so will not be cached.

_menu_build in includes/menu.inc

Build the menu by querying both modules and the database.

_menu_build_visible_tree in includes/menu.inc

Find all visible items in the menu tree, for ease in displaying to user.