Bug 905230 - Use LinkedList for nsXBLJSClass; r=mrbkap

content/xbl/src/nsXBLBinding.cpp

@@ -94,9 +94,11 @@ uint64_t nsXBLJSClass::sIdCount = 0;
 
 nsXBLJSClass::nsXBLJSClass(const nsAFlatCString& aClassName,
                            const nsCString& aKey)
+  : LinkedListElement<nsXBLJSClass>()
+  , mRefCnt(0)
+  , mKey(aKey)
 {
-  memset(this, 0, sizeof(nsXBLJSClass));
-  next = prev = static_cast<JSCList*>(this);
+  memset(static_cast<JSClass*>(this), 0, sizeof(JSClass));
   name = ToNewCString(aClassName);
   flags =
     JSCLASS_HAS_PRIVATE | JSCLASS_PRIVATE_IS_NSISUPPORTS |
@@ -110,13 +112,12 @@ nsXBLJSClass::nsXBLJSClass(const nsAFlatCString& aClassName,
   resolve = JS_ResolveStub;
   convert = ::JS_ConvertStub;
   finalize = XBLFinalize;
-  mKey = aKey;
 }
 
 nsrefcnt
 nsXBLJSClass::Destroy()
 {
-  NS_ASSERTION(next == prev && prev == static_cast<JSCList*>(this),
+  NS_ASSERTION(!isInList(),
                "referenced nsXBLJSClass is on LRU list already!?");
 
   if (nsXBLService::gClassTable) {
@@ -130,8 +131,7 @@ nsXBLJSClass::Destroy()
     delete this;
   } else {
     // Put this most-recently-used class on end of the LRU-sorted freelist.
-    JSCList* mru = static_cast<JSCList*>(this);
-    JS_APPEND_LINK(mru, &nsXBLService::gClassLRUList);
+    nsXBLService::gClassLRUList->insertBack(this);
     nsXBLService::gClassLRUListLength++;
   }
 
@@ -957,27 +957,21 @@ nsXBLBinding::DoInitJSClass(JSContext *cx, JS::Handle<JSObject*> global,
       c = static_cast<nsXBLJSClass*>(nsXBLService::gClassTable->Get(&key));
     }
     if (c) {
-      // If c is on the LRU list (i.e., not linked to itself), remove it now!
-      JSCList* link = static_cast<JSCList*>(c);
-      if (c->next != link) {
-        JS_REMOVE_AND_INIT_LINK(link);
+      // If c is on the LRU list, remove it now!
+      if (c->isInList()) {
+        c->remove();
         nsXBLService::gClassLRUListLength--;
       }
     } else {
-      if (JS_CLIST_IS_EMPTY(&nsXBLService::gClassLRUList)) {
+      if (nsXBLService::gClassLRUList->isEmpty()) {
         // We need to create a struct for this class.
         c = new nsXBLJSClass(className, xblKey);
-
-        if (!c)
-          return NS_ERROR_OUT_OF_MEMORY;
       } else {
         // Pull the least recently used class struct off the list.
-        JSCList* lru = (nsXBLService::gClassLRUList).next;
-        JS_REMOVE_AND_INIT_LINK(lru);
+        c = nsXBLService::gClassLRUList->popFirst();
         nsXBLService::gClassLRUListLength--;
 
         // Remove any mapping from the old name to the class struct.
-        c = static_cast<nsXBLJSClass*>(lru);
         nsCStringKey oldKey(c->Key());
         (nsXBLService::gClassTable)->Remove(&oldKey);
 

content/xbl/src/nsXBLService.cpp

@@ -369,7 +369,7 @@ bool nsXBLService::gAllowDataURIs = false;
 
 nsHashtable* nsXBLService::gClassTable = nullptr;
 
-JSCList  nsXBLService::gClassLRUList = JS_INIT_STATIC_CLIST(&nsXBLService::gClassLRUList);
+LinkedList<nsXBLJSClass>* nsXBLService::gClassLRUList = nullptr;
 uint32_t nsXBLService::gClassLRUListLength = 0;
 uint32_t nsXBLService::gClassLRUListQuota = 64;
 
@@ -393,6 +393,7 @@ nsXBLService::Init()
 nsXBLService::nsXBLService(void)
 {
   gClassTable = new nsHashtable();
+  gClassLRUList = new LinkedList<nsXBLJSClass>();
 
   Preferences::AddBoolVarCache(&gAllowDataURIs, "layout.debug.enable_data_xbl");
 }
@@ -406,6 +407,8 @@ nsXBLService::~nsXBLService(void)
   // created for bindings will be deleted when those objects are finalized
   // (and not put on gClassLRUList, because length >= quota).
   gClassLRUListLength = gClassLRUListQuota = 0;
+  delete gClassLRUList;
+  gClassLRUList = nullptr;
 
   // At this point, the only hash table entries should be for referenced
   // XBL class structs held by unfinalized JS binding objects.
@@ -642,11 +645,8 @@ nsXBLService::Observe(nsISupports* aSubject, const char* aTopic, const PRUnichar
 nsresult
 nsXBLService::FlushMemory()
 {
-  while (!JS_CLIST_IS_EMPTY(&gClassLRUList)) {
-    JSCList* lru = gClassLRUList.next;
-    nsXBLJSClass* c = static_cast<nsXBLJSClass*>(lru);
-
-    JS_REMOVE_AND_INIT_LINK(lru);
+  while (!gClassLRUList->isEmpty()) {
+    nsXBLJSClass* c = gClassLRUList->popFirst();
     delete c;
     gClassLRUListLength--;
   }

content/xbl/src/nsXBLService.h

@@ -8,15 +8,16 @@
 #ifndef nsXBLService_h_
 #define nsXBLService_h_
 
+#include "mozilla/LinkedList.h"
 #include "nsString.h"
 #include "nsIObserver.h"
 #include "nsWeakReference.h"
 #include "jsapi.h"              // nsXBLJSClass derives from JSClass
-#include "jsclist.h"            // nsXBLJSClass derives from JSCList
 #include "nsTArray.h"
 
 class nsXBLBinding;
 class nsXBLDocumentInfo;
+class nsXBLJSClass;
 class nsIContent;
 class nsIDocument;
 class nsString;
@@ -124,7 +125,8 @@ public:
 
   static nsHashtable* gClassTable;           // A table of nsXBLJSClass objects.
 
-  static JSCList  gClassLRUList;             // LRU list of cached classes.
+  static mozilla::LinkedList<nsXBLJSClass>* gClassLRUList;
+                                             // LRU list of cached classes.
   static uint32_t gClassLRUListLength;       // Number of classes on LRU list.
   static uint32_t gClassLRUListQuota;        // Quota on class LRU list.
   static bool     gAllowDataURIs;            // Whether we should allow data
@@ -132,7 +134,8 @@ public:
                                              // testing.
 };
 
-class nsXBLJSClass : public JSCList, public JSClass
+class nsXBLJSClass : public mozilla::LinkedListElement<nsXBLJSClass>
+                   , public JSClass
 {
 private:
   nsrefcnt mRefCnt;