--- a/js/src/devtools/rootAnalysis/annotations.js
+++ b/js/src/devtools/rootAnalysis/annotations.js
@@ -1,24 +1,23 @@
 /* -*- Mode: Javascript; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
 
 "use strict";
 
+// Ignore calls made through these function pointers
 var ignoreIndirectCalls = {
     "mallocSizeOf" : true,
     "aMallocSizeOf" : true,
     "_malloc_message" : true,
     "__conv" : true,
     "__convf" : true,
     "prerrortable.c:callback_newtable" : true,
     "mozalloc_oom.cpp:void (* gAbortHandler)(size_t)" : true,
-    "JSObject* js::GetWeakmapKeyDelegate(JSObject*)" : true, // FIXME: mark with AutoAssertNoGC instead
 };
 
-
 function indirectCallCannotGC(caller, name)
 {
     if (name in ignoreIndirectCalls)
         return true;
 
     if (name == "mapper" && caller == "ptio.c:pt_MapError")
         return true;
 
@@ -27,28 +26,30 @@ function indirectCallCannotGC(caller, na
 
     // hook called during script finalization which cannot GC.
     if (/CallDestroyScriptHook/.test(caller))
         return true;
 
     return false;
 }
 
-// classes to ignore indirect calls on.
+// Ignore calls through functions pointers with these types
 var ignoreClasses = {
     "JSTracer" : true,
     "JSStringFinalizer" : true,
     "SprintfStateStr" : true,
     "JSLocaleCallbacks" : true,
     "JSC::ExecutableAllocator" : true,
     "PRIOMethods": true,
     "XPCOMFunctions" : true, // I'm a little unsure of this one
     "_MD_IOVector" : true,
 };
 
+// Ignore calls through TYPE.FIELD, where TYPE is the class or struct name containing
+// a function pointer field named FIELD.
 var ignoreCallees = {
     "js::Class.trace" : true,
     "js::Class.finalize" : true,
     "JSRuntime.destroyPrincipals" : true,
     "nsISupports.AddRef" : true,
     "nsISupports.Release" : true, // makes me a bit nervous; this is a bug but can happen
     "nsAXPCNativeCallContext.GetJSContext" : true,
     "js::ion::MDefinition.op" : true, // macro generated virtuals just return a constant
@@ -91,21 +92,23 @@ function ignoreEdgeUse(edge, variable)
             if (/~DebugOnly/.test(name))
                 return true;
         }
     }
 
     return false;
 }
 
+// Ignore calls of these functions (so ignore any stack containing these)
 var ignoreFunctions = {
     "ptio.c:pt_MapError" : true,
     "PR_ExplodeTime" : true,
     "PR_ErrorInstallTable" : true,
-    "PR_SetThreadPrivate" : true
+    "PR_SetThreadPrivate" : true,
+    "JSObject* js::GetWeakmapKeyDelegate(JSObject*)" : true, // FIXME: mark with AutoAssertNoGC instead
 };
 
 function ignoreGCFunction(fun)
 {
     if (fun in ignoreFunctions)
         return true;
 
     // Templatized function