1 files changed, 1 insertions, 45 deletions

diff --git a/js/src/gc/Marking.cpp b/js/src/gc/Marking.cpp
index 3ea4c9d29..47d2314c1 100644
--- a/js/src/gc/Marking.cpp
+++ b/js/src/gc/Marking.cpp
@@ -18,6 +18,7 @@
 #include "builtin/ModuleObject.h"
 #include "gc/GCInternals.h"
 #include "gc/Policy.h"
+#include "gc/StoreBuffer-inl.h"
 #include "jit/IonCode.h"
 #include "js/SliceBudget.h"
 #include "vm/ArgumentsObject.h"
@@ -28,7 +29,6 @@
 #include "vm/Shape.h"
 #include "vm/Symbol.h"
 #include "vm/TypedArrayObject.h"
-#include "vm/UnboxedObject.h"
 #include "wasm/WasmJS.h"
 
 #include "jscompartmentinlines.h"
@@ -37,7 +37,6 @@
 
 #include "gc/Nursery-inl.h"
 #include "vm/String-inl.h"
-#include "vm/UnboxedObject-inl.h"
 
 using namespace js;
 using namespace js::gc;
@@ -1395,14 +1394,6 @@ js::ObjectGroup::traceChildren(JSTracer* trc)
     if (maybePreliminaryObjects())
         maybePreliminaryObjects()->trace(trc);
 
-    if (maybeUnboxedLayout())
-        unboxedLayout().trace(trc);
-
-    if (ObjectGroup* unboxedGroup = maybeOriginalUnboxedGroup()) {
-        TraceManuallyBarrieredEdge(trc, &unboxedGroup, "group_original_unboxed_group");
-        setOriginalUnboxedGroup(unboxedGroup);
-    }
-
     if (JSObject* descr = maybeTypeDescr()) {
         TraceManuallyBarrieredEdge(trc, &descr, "group_type_descr");
         setTypeDescr(&descr->as<TypeDescr>());
@@ -1436,12 +1427,6 @@ js::GCMarker::lazilyMarkChildren(ObjectGroup* group)
     if (group->maybePreliminaryObjects())
         group->maybePreliminaryObjects()->trace(this);
 
-    if (group->maybeUnboxedLayout())
-        group->unboxedLayout().trace(this);
-
-    if (ObjectGroup* unboxedGroup = group->maybeOriginalUnboxedGroup())
-        traverseEdge(group, unboxedGroup);
-
     if (TypeDescr* descr = group->maybeTypeDescr())
         traverseEdge(group, static_cast<JSObject*>(descr));
 
@@ -1484,23 +1469,6 @@ CallTraceHook(Functor f, JSTracer* trc, JSObject* obj, CheckGeneration check, Ar
         return nullptr;
     }
 
-    if (clasp == &UnboxedPlainObject::class_) {
-        JSObject** pexpando = obj->as<UnboxedPlainObject>().addressOfExpando();
-        if (*pexpando)
-            f(pexpando, mozilla::Forward<Args>(args)...);
-
-        UnboxedPlainObject& unboxed = obj->as<UnboxedPlainObject>();
-        const UnboxedLayout& layout = check == CheckGeneration::DoChecks
-                                      ? unboxed.layout()
-                                      : unboxed.layoutDontCheckGeneration();
-        if (layout.traceList()) {
-            VisitTraceList(f, layout.traceList(), unboxed.data(),
-                           mozilla::Forward<Args>(args)...);
-        }
-
-        return nullptr;
-    }
-
     clasp->doTrace(trc, obj);
 
     if (!clasp->isNative())
@@ -2293,18 +2261,6 @@ static inline void
 TraceWholeCell(TenuringTracer& mover, JSObject* object)
 {
     mover.traceObject(object);
-
-    // Additionally trace the expando object attached to any unboxed plain
-    // objects. Baseline and Ion can write properties to the expando while
-    // only adding a post barrier to the owning unboxed object. Note that
-    // it isn't possible for a nursery unboxed object to have a tenured
-    // expando, so that adding a post barrier on the original object will
-    // capture any tenured->nursery edges in the expando as well.
-
-    if (object->is<UnboxedPlainObject>()) {
-        if (UnboxedExpandoObject* expando = object->as<UnboxedPlainObject>().maybeExpando())
-            expando->traceChildren(&mover);
-    }
 }
 
 static inline void