Bug 989320 - Add cycle collection support for MFBT EnumeratedArray - r=mccr8

xpcom/glue/EnumeratedArrayCycleCollection.h

@@ -0,0 +1,43 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef EnumeratedArrayCycleCollection_h_
+#define EnumeratedArrayCycleCollection_h_
+
+#include "mozilla/EnumeratedArray.h"
+#include "nsCycleCollectionTraversalCallback.h"
+
+template <typename IndexType,
+          MOZ_TEMPLATE_ENUM_CLASS_ENUM_TYPE(IndexType) SizeAsEnumValue,
+          typename ValueType>
+inline void
+ImplCycleCollectionUnlink(mozilla::EnumeratedArray<IndexType,
+                                                   SizeAsEnumValue,
+                                                   ValueType>& aField)
+{
+  for (size_t i = 0; i < size_t(SizeAsEnumValue); i++) {
+    aField[IndexType(i)] = nullptr;
+  }
+}
+
+template <typename IndexType,
+          MOZ_TEMPLATE_ENUM_CLASS_ENUM_TYPE(IndexType) SizeAsEnumValue,
+          typename ValueType>
+inline void
+ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback& aCallback,
+                            mozilla::EnumeratedArray<IndexType,
+                                                     SizeAsEnumValue,
+                                                     ValueType>& aField,
+                            const char* aName,
+                            uint32_t aFlags = 0)
+{
+  aFlags |= CycleCollectionEdgeNameArrayFlag;
+  for (size_t i = 0; i < size_t(SizeAsEnumValue); ++i) {
+    ImplCycleCollectionTraverse(aCallback, aField[IndexType(i)], aName, aFlags);
+  }
+}
+
+#endif // EnumeratedArrayCycleCollection_h_

xpcom/glue/moz.build

@@ -69,6 +69,7 @@ EXPORTS.mozilla += [
     'BlockingResourceBase.h',
     'CondVar.h',
     'DeadlockDetector.h',
+    'EnumeratedArrayCycleCollection.h',
     'FileUtils.h',
     'GenericFactory.h',
     'HoldDropJSObjects.h',