Index: third_party/WebKit/Source/wtf/StdLibExtras.h |
diff --git a/third_party/WebKit/Source/wtf/StdLibExtras.h b/third_party/WebKit/Source/wtf/StdLibExtras.h |
index 5475d3feb7e47a9e4b1ee0552abfadca7f508e13..6f3709a9fa455842edba6dd8f2ca49147607e1fb 100644 |
--- a/third_party/WebKit/Source/wtf/StdLibExtras.h |
+++ b/third_party/WebKit/Source/wtf/StdLibExtras.h |
@@ -59,34 +59,57 @@ private: |
}; |
#endif |
-// A direct static local to a Blink garbage collected objects isn't allowed; |
-// must be wrapped up with a persistent reference. |
-#define STATIC_ASSERT_FOR_LOCAL_WITH_GARBAGE_COLLECTED_TYPE(Name, Type) \ |
- using Name##NoConstType = std::remove_const<Type>::type; \ |
- using Name##NoPointerType = std::remove_pointer<Name##NoConstType>::type; \ |
- using Name##NoReferenceType = std::remove_reference<Name##NoPointerType>::type; \ |
- static_assert(!WTF::IsGarbageCollectedType<Name##NoReferenceType>::value || WTF::IsPersistentReferenceType<Name##NoReferenceType>::value, "Garbage collected static local needs to be wrapped up with a persistent reference") |
- |
-// Use DEFINE_STATIC_LOCAL() to declare and define a static local variable (static T;) |
-// so that it is leaked and its destructors are not called at exit. |
-// |
-// To cooperate with leak detection, the objects held onto by these local statics |
-// will in some cases have to be finalized prior to leak checking. This only applies |
-// to static references to Oilpan heap objects and what they transitively hold on to. |
-// LEAK_SANITIZER_REGISTER_STATIC_LOCAL() takes care of the details. |
-// |
+namespace blink { |
+template<typename T>class Persistent; |
+}; |
+ |
+template<typename T, bool = WTF::IsGarbageCollectedType<T>::value && !WTF::IsPersistentReferenceType<T>::value> |
+class StaticLocalWrapper { |
+public: |
+ using WrapType = T; |
+ |
+ static T& unwrap(T* singleton) |
+ { |
+ return *singleton; |
+ } |
+}; |
+ |
+template<typename T> |
+class StaticLocalWrapper<T, true> { |
+public: |
+ using WrapType = blink::Persistent<T>; |
+ |
+ static T& unwrap(blink::Persistent<T>* singleton) |
+ { |
+ return **singleton; |
+ } |
+}; |
+ |
#if ENABLE(ASSERT) |
-#define DEFINE_STATIC_LOCAL(Type, Name, Arguments) \ |
- STATIC_ASSERT_FOR_LOCAL_WITH_GARBAGE_COLLECTED_TYPE(Name, Type); \ |
+#define DEFINE_STATIC_LOCAL_CHECK_THREADSAFE_ACCESS(Name) \ |
static StaticLocalVerifier Name##StaticLocalVerifier; \ |
- ASSERT(Name##StaticLocalVerifier.isNotRacy()); \ |
- static Type& Name = *LEAK_SANITIZER_REGISTER_STATIC_LOCAL(Type, new Type Arguments) |
+ ASSERT(Name##StaticLocalVerifier.isNotRacy()) |
#else |
-#define DEFINE_STATIC_LOCAL(Type, Name, Arguments) \ |
- STATIC_ASSERT_FOR_LOCAL_WITH_GARBAGE_COLLECTED_TYPE(Name, Type); \ |
- static Type& Name = *LEAK_SANITIZER_REGISTER_STATIC_LOCAL(Type, new Type Arguments) |
+#define DEFINE_STATIC_LOCAL_CHECK_THREADSAFE_ACCESS(Name) |
#endif |
+// Use DEFINE_STATIC_LOCAL() to declare and define a static local variable |
+// (static T;) so that it is leaked and its destructors are not called at exit. |
+// T may also be a Blink garbage collected object, in which case it is |
+// wrapped up by a strong off-heap Persistent<T> reference. |
haraken
2016/04/03 23:46:52
Nit: "strong off-heap" might be misleading. "a str
sof
2016/04/04 07:09:00
Reworded.
|
+// |
+// To cooperate with leak detection(LSan) for Blink garbage collected objects, |
+// the objects owned by persistent local statics will in some cases have to be |
+// finalized prior to leak checking. This only applies to static references to |
+// Blink heap objects and what they transitively hold on to. Hence the |
+// LEAK_SANITIZER_REGISTER_STATIC_LOCAL() use, it taking care of the grungy |
+// details. |
+// |
+#define DEFINE_STATIC_LOCAL(Type, Name, Arguments) \ |
+ DEFINE_STATIC_LOCAL_CHECK_THREADSAFE_ACCESS(Name); \ |
+ using WrappedTypeFor##Name = StaticLocalWrapper<Type>::WrapType; \ |
+ static Type& Name = StaticLocalWrapper<Type>::unwrap(LEAK_SANITIZER_REGISTER_STATIC_LOCAL(WrappedTypeFor##Name, new WrappedTypeFor##Name Arguments)) |
+ |
// Use this to declare and define a static local pointer to a ref-counted object so that |
// it is leaked so that the object's destructors are not called at exit. |
// This macro should be used with ref-counted objects rather than DEFINE_STATIC_LOCAL macro, |