Cache legacy callback interface objects in proto_or_icache_array

We need them to be cached to not instantiate them multiple times with
lazy initialisation.

2 files changed, 24 insertions, 12 deletions

diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index 99d60e379b6..6ae07873dca 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -2379,9 +2379,8 @@ class CGCreateInterfaceObjectsMethod(CGAbstractMethod):
     properties should be a PropertyArrays instance.
     """
     def __init__(self, descriptor, properties):
-        args = [Argument('*mut JSContext', 'cx'), Argument('HandleObject', 'global')]
-        if not descriptor.interface.isCallback():
-            args.append(Argument('*mut ProtoOrIfaceArray', 'cache'))
+        args = [Argument('*mut JSContext', 'cx'), Argument('HandleObject', 'global'),
+                Argument('*mut ProtoOrIfaceArray', 'cache')]
         CGAbstractMethod.__init__(self, descriptor, 'CreateInterfaceObjects', 'void', args,
                                   unsafe=True)
         self.properties = properties
@@ -2391,7 +2390,14 @@ class CGCreateInterfaceObjectsMethod(CGAbstractMethod):
         if self.descriptor.interface.isCallback():
             assert not self.descriptor.interface.ctor() and self.descriptor.interface.hasConstants()
             return CGGeneric("""\
-create_callback_interface_object(cx, global, sConstants, %s);""" % str_to_const_array(name))
+let mut interface = RootedObject::new(cx, ptr::null_mut());
+create_callback_interface_object(cx, global, sConstants, %(name)s, interface.handle_mut());
+assert!(!interface.ptr.is_null());
+(*cache)[PrototypeList::Constructor::%(id)s as usize] = interface.ptr;
+if <*mut JSObject>::needs_post_barrier(interface.ptr) {
+    <*mut JSObject>::post_barrier((*cache).as_mut_ptr().offset(PrototypeList::Constructor::%(id)s as isize));
+}
+""" % {"id": name, "name": str_to_const_array(name)})
 
         if len(self.descriptor.prototypeChain) == 1:
             if self.descriptor.interface.getExtendedAttribute("ExceptionClass"):
@@ -2672,14 +2678,14 @@ class CGDefineDOMInterfaceMethod(CGAbstractMethod):
 
     def definition_body(self):
         if self.descriptor.interface.isCallback():
-            code = "CreateInterfaceObjects(cx, global);"
+            function = "GetConstructorObject"
         else:
-            code = """\
+            function = "GetProtoObject"
+        return CGGeneric("""\
+assert!(!global.get().is_null());
 let mut proto = RootedObject::new(cx, ptr::null_mut());
-GetProtoObject(cx, global, proto.handle_mut());
-assert!(!proto.ptr.is_null());
-"""
-        return CGGeneric("assert!(!global.get().is_null());\n" + code)
+%s(cx, global, proto.handle_mut());
+assert!(!proto.ptr.is_null());""" % function)
 
 
 def needCx(returnType, arguments, considerTypes):
@@ -4956,7 +4962,8 @@ class CGDescriptor(CGThing):
         cgThings = []
         if not descriptor.interface.isCallback():
             cgThings.append(CGGetProtoObjectMethod(descriptor))
-        if descriptor.interface.hasInterfaceObject() and descriptor.hasDescendants():
+        if (descriptor.interface.hasInterfaceObject() and
+                descriptor.shouldHaveGetConstructorObjectMethod()):
             cgThings.append(CGGetConstructorObjectMethod(descriptor))
 
         for m in descriptor.interface.members:
@@ -6093,7 +6100,8 @@ class GlobalGenRoots():
         # Prototype ID enum.
         interfaces = config.getDescriptors(isCallback=False)
         protos = [d.name for d in interfaces]
-        constructors = [d.name for d in interfaces if d.hasDescendants()]
+        constructors = [d.name for d in config.getDescriptors(hasInterfaceObject=True)
+                        if d.shouldHaveGetConstructorObjectMethod()]
         proxies = [d.name for d in config.getDescriptors(proxy=True)]
 
         return CGList([
diff --git a/components/script/dom/bindings/codegen/Configuration.py b/components/script/dom/bindings/codegen/Configuration.py
index 762998b91ac..c634665c410 100644
--- a/components/script/dom/bindings/codegen/Configuration.py
+++ b/components/script/dom/bindings/codegen/Configuration.py
@@ -345,6 +345,10 @@ class Descriptor(DescriptorProvider):
         return (self.interface.getUserData("hasConcreteDescendant", False) or
                 self.interface.getUserData("hasProxyDescendant", False))
 
+    def shouldHaveGetConstructorObjectMethod(self):
+        assert self.interface.hasInterfaceObject()
+        return self.interface.isCallback() or self.hasDescendants()
+
     def isGlobal(self):
         """
         Returns true if this is the primary interface for a global object