diff options
| -rw-r--r-- | gcc/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/is-a.h | 24 |
2 files changed, 28 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 55b41ae582f..bc5c327b931 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,7 @@ +2014-08-18 David Malcolm <dmalcolm@redhat.com> + + * is-a.h (template<T, U> safe_as_a <U *p>) New function. + 2014-08-18 Jan Hubicka <hubicka@ucw.cz> * ipa-visibility.c (update_visibility_by_resolution_info): Do no turn UNDEF diff --git a/gcc/is-a.h b/gcc/is-a.h index a14e344761a..176066b42bc 100644 --- a/gcc/is-a.h +++ b/gcc/is-a.h @@ -46,6 +46,14 @@ TYPE as_a <TYPE> (pointer) do_something_with (as_a <cgraph_node *> *ptr); +TYPE safe_as_a <TYPE> (pointer) + + Like as_a <TYPE> (pointer), but where pointer could be NULL. This + adds a check against NULL where the regular is_a_helper hook for TYPE + assumes non-NULL. + + do_something_with (safe_as_a <cgraph_node *> *ptr); + TYPE dyn_cast <TYPE> (pointer) Converts pointer to TYPE if and only if "is_a <TYPE> pointer". Otherwise, @@ -185,6 +193,22 @@ as_a (U *p) return is_a_helper <T>::cast (p); } +/* Similar to as_a<>, but where the pointer can be NULL, even if + is_a_helper<T> doesn't check for NULL. */ + +template <typename T, typename U> +inline T +safe_as_a (U *p) +{ + if (p) + { + gcc_checking_assert (is_a <T> (p)); + return is_a_helper <T>::cast (p); + } + else + return NULL; +} + /* A generic checked conversion from a base type U to a derived type T. See the discussion above for when to use this function. */ |