--- a/js/src/jsobj.cpp
+++ b/js/src/jsobj.cpp
@@ -2368,16 +2368,49 @@ js::GetPropertyPure(ExclusiveContext* cx
     if (!shape) {
         vp->setUndefined();
         return true;
     }
 
     return pobj->isNative() && NativeGetPureInline(&pobj->as<NativeObject>(), shape, vp);
 }
 
+static inline bool
+NativeGetGetterPureInline(NativeObject* pobj, Shape* shape, JSFunction** fp)
+{
+    if (shape->hasGetterObject()) {
+        if (shape->getterObject()->is<JSFunction>()) {
+            *fp = &shape->getterObject()->as<JSFunction>();
+            return true;
+        }
+    }
+
+    *fp = nullptr;
+    return true;
+}
+
+bool
+js::GetGetterPure(ExclusiveContext* cx, JSObject* obj, jsid id, JSFunction** fp)
+{
+    /* Just like GetPropertyPure, but get getter function, without invoking
+     * it. */
+    JSObject* pobj;
+    Shape* shape;
+    if (!LookupPropertyPure(cx, obj, id, &pobj, &shape))
+        return false;
+
+    if (!shape) {
+        *fp = nullptr;
+        return true;
+    }
+
+    return pobj->isNative() &&
+           NativeGetGetterPureInline(&pobj->as<NativeObject>(), shape, fp);
+}
+
 bool
 JSObject::reportReadOnly(JSContext* cx, jsid id, unsigned report)
 {
     RootedValue val(cx, IdToValue(id));
     return ReportValueErrorFlags(cx, report, JSMSG_READ_ONLY,
                                  JSDVG_IGNORE_STACK, val, nullptr,
                                  nullptr, nullptr);
 }

--- a/js/src/jsobj.h
+++ b/js/src/jsobj.h
@@ -1216,16 +1216,19 @@ FindVariableScope(JSContext* cx, JSFunct
 bool
 LookupPropertyPure(ExclusiveContext* cx, JSObject* obj, jsid id, JSObject** objp,
                    Shape** propp);
 
 bool
 GetPropertyPure(ExclusiveContext* cx, JSObject* obj, jsid id, Value* vp);
 
 bool
+GetGetterPure(ExclusiveContext* cx, JSObject* obj, jsid id, JSFunction** fp);
+
+bool
 GetOwnPropertyDescriptor(JSContext* cx, HandleObject obj, HandleId id,
                          MutableHandle<PropertyDescriptor> desc);
 
 bool
 GetOwnPropertyDescriptor(JSContext* cx, HandleObject obj, HandleId id, MutableHandleValue vp);
 
 /*
  * ES6 draft rev 32 (2015 Feb 2) 6.2.4.4 FromPropertyDescriptor(Desc).