Bug 1297244 - Assert on the type given as a parameter to Heap. r=terrence

--HG--
extra : rebase_source : 2523f190a45bf3669f40392226df6a0b6fbc9806

dom/xbl/nsXBLMaybeCompiled.h

@@ -116,6 +116,12 @@ struct BarrierMethods<nsXBLMaybeCompiled<UncompiledT>>
   }
 };
 
+template <class T>
+struct IsHeapConstructibleType<nsXBLMaybeCompiled<T>>
+{ // Yes, this is the exception to the rule. Sorry.
+  static constexpr bool value = true;
+};
+
 template <class UncompiledT>
 class HeapBase<nsXBLMaybeCompiled<UncompiledT>>
 {

js/public/GCPolicyAPI.h

@@ -45,6 +45,23 @@
 #include "js/TraceKind.h"
 #include "js/TracingAPI.h"
 
+// Expand the given macro D for each public GC pointer.
+#define FOR_EACH_PUBLIC_GC_POINTER_TYPE(D) \
+    D(JS::Symbol*) \
+    D(JSAtom*) \
+    D(JSFunction*) \
+    D(JSObject*) \
+    D(JSScript*) \
+    D(JSString*)
+
+// Expand the given macro D for each public tagged GC pointer type.
+#define FOR_EACH_PUBLIC_TAGGED_GC_POINTER_TYPE(D) \
+    D(JS::Value) \
+    D(jsid)
+
+#define FOR_EACH_PUBLIC_AGGREGATE_GC_POINTER_TYPE(D) \
+    D(JSPropertyDescriptor)
+
 class JSAtom;
 class JSFunction;
 class JSObject;

js/public/RootingAPI.h

@@ -14,6 +14,8 @@
 #include "mozilla/Move.h"
 #include "mozilla/TypeTraits.h"
 
+#include <type_traits>
+
 #include "jspubtd.h"
 
 #include "js/GCAnnotations.h"
@@ -123,6 +125,14 @@ class MutableHandleBase {};
 template <typename T>
 class HeapBase {};
 
+// Cannot use FOR_EACH_HEAP_ABLE_GC_POINTER_TYPE, as this would import too many macros into scope
+template <typename T> struct IsHeapConstructibleType    { static constexpr bool value = false; };
+#define DECLARE_IS_HEAP_CONSTRUCTIBLE_TYPE(T) \
+    template <> struct IsHeapConstructibleType<T> { static constexpr bool value = true; };
+FOR_EACH_PUBLIC_GC_POINTER_TYPE(DECLARE_IS_HEAP_CONSTRUCTIBLE_TYPE)
+FOR_EACH_PUBLIC_TAGGED_GC_POINTER_TYPE(DECLARE_IS_HEAP_CONSTRUCTIBLE_TYPE)
+#undef DECLARE_IS_HEAP_CONSTRUCTIBLE_TYPE
+
 template <typename T>
 class PersistentRootedBase {};
 
@@ -214,11 +224,14 @@ AssertGCThingIsNotAnObjectSubclass(js::gc::Cell* cell) {}
  * Heap<T> objects should only be used on the heap. GC references stored on the
  * C/C++ stack must use Rooted/Handle/MutableHandle instead.
  *
- * Type T must be one of: JS::Value, jsid, JSObject*, JSString*, JSScript*
+ * Type T must be a public GC pointer type.
  */
 template <typename T>
 class Heap : public js::HeapBase<T>
 {
+    // Please note: this can actually also be used by nsXBLMaybeCompiled<T>, for legacy reasons.
+    static_assert(js::IsHeapConstructibleType<T>::value,
+                  "Type T must be a public GC pointer type");
   public:
     Heap() {
         static_assert(sizeof(T) == sizeof(Heap<T>),

js/src/gc/Marking.cpp

@@ -2791,9 +2791,12 @@ EdgeNeedsSweep(JS::Heap<T>* thingp)
     template bool IsMarked<type>(WriteBarrieredBase<type>*); \
     template bool IsAboutToBeFinalizedUnbarriered<type>(type*); \
     template bool IsAboutToBeFinalized<type>(WriteBarrieredBase<type>*); \
-    template bool IsAboutToBeFinalized<type>(ReadBarrieredBase<type>*); \
+    template bool IsAboutToBeFinalized<type>(ReadBarrieredBase<type>*);
+#define INSTANTIATE_ALL_VALID_HEAP_TRACE_FUNCTIONS(type) \
     template JS_PUBLIC_API(bool) EdgeNeedsSweep<type>(JS::Heap<type>*);
 FOR_EACH_GC_POINTER_TYPE(INSTANTIATE_ALL_VALID_TRACE_FUNCTIONS)
+FOR_EACH_PUBLIC_GC_POINTER_TYPE(INSTANTIATE_ALL_VALID_HEAP_TRACE_FUNCTIONS)
+FOR_EACH_PUBLIC_TAGGED_GC_POINTER_TYPE(INSTANTIATE_ALL_VALID_HEAP_TRACE_FUNCTIONS)
 #undef INSTANTIATE_ALL_VALID_TRACE_FUNCTIONS
 
 } /* namespace gc */

js/src/gc/Policy.h

@@ -58,23 +58,6 @@ class JitCode;
 } // namespace jit
 } // namespace js
 
-// Expand the given macro D for each public GC pointer.
-#define FOR_EACH_PUBLIC_GC_POINTER_TYPE(D) \
-    D(JS::Symbol*) \
-    D(JSAtom*) \
-    D(JSFunction*) \
-    D(JSObject*) \
-    D(JSScript*) \
-    D(JSString*)
-
-// Expand the given macro D for each public tagged GC pointer type.
-#define FOR_EACH_PUBLIC_TAGGED_GC_POINTER_TYPE(D) \
-    D(JS::Value) \
-    D(jsid)
-
-#define FOR_EACH_PUBLIC_AGGREGATE_GC_POINTER_TYPE(D) \
-    D(JSPropertyDescriptor)
-
 // Expand the given macro D for each valid GC reference type.
 #define FOR_EACH_INTERNAL_GC_POINTER_TYPE(D) \
     D(JSFlatString*) \