Bug 673125: Provide stack-allocated vectors of JSObject pointers. r=luke.

js/src/jscntxt.h

@@ -1482,7 +1482,8 @@ class AutoGCRooter {
         STRING =      -14, /* js::AutoStringRooter */
         IDVECTOR =    -15, /* js::AutoIdVector */
         BINDINGS =    -16, /* js::Bindings */
-        SHAPEVECTOR = -17  /* js::AutoShapeVector */
+        SHAPEVECTOR = -17, /* js::AutoShapeVector */
+        OBJVECTOR =   -18  /* js::AutoObjectVector */
     };
 
     private:
@@ -2487,6 +2488,19 @@ class AutoValueVector : public AutoVectorRooter<Value>
     JS_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 
+class AutoObjectVector : public AutoVectorRooter<JSObject *>
+{
+  public:
+    explicit AutoObjectVector(JSContext *cx
+                              JS_GUARD_OBJECT_NOTIFIER_PARAM)
+        : AutoVectorRooter<JSObject *>(cx, OBJVECTOR)
+    {
+        JS_GUARD_OBJECT_NOTIFIER_INIT;
+    }
+
+    JS_DECL_USE_GUARD_OBJECT_NOTIFIER
+};
+
 class AutoIdVector : public AutoVectorRooter<jsid>
 {
   public:

js/src/jsgc.cpp

@@ -1784,6 +1784,12 @@ AutoGCRooter::trace(JSTracer *trc)
         static_cast<js::AutoBindingsRooter *>(this)->bindings.trace(trc);
         return;
       }
+
+      case OBJVECTOR: {
+        AutoObjectVector::VectorImpl &vector = static_cast<AutoObjectVector *>(this)->vector;
+        MarkObjectRange(trc, vector.length(), vector.begin(), "js::AutoObjectVector.vector");
+        return;
+      }
     }
 
     JS_ASSERT(tag >= 0);