Bug 1425450 - Pass zone information through when preserving wrappers r=mccr8

This is bascially the same as your original patch.

Differential Revision: https://phabricator.services.mozilla.com/D68520

dom/base/nsWrapperCache.cpp

@@ -24,8 +24,9 @@ bool nsWrapperCache::HasJSObjectMovedOp(JSObject* aWrapper) {
 #endif
 
 void nsWrapperCache::HoldJSObjects(void* aScriptObjectHolder,
-                                   nsScriptObjectTracer* aTracer) {
-  cyclecollector::HoldJSObjectsImpl(aScriptObjectHolder, aTracer);
+                                   nsScriptObjectTracer* aTracer,
+                                   JS::Zone* aWrapperZone) {
+  cyclecollector::HoldJSObjectsImpl(aScriptObjectHolder, aTracer, aWrapperZone);
   if (mWrapper && !JS::ObjectIsTenured(mWrapper)) {
     CycleCollectedJSRuntime::Get()->NurseryWrapperPreserved(mWrapper);
   }

dom/base/nsWrapperCache.h

@@ -13,6 +13,7 @@
 #include "js/Value.h"  // must come before js/RootingAPI.h
 #include "js/RootingAPI.h"
 #include "js/TracingAPI.h"
+#include "jsfriendapi.h"
 
 namespace mozilla {
 namespace dom {
@@ -184,6 +185,8 @@ class nsWrapperCache {
    * any wrapper cached object.
    */
   void UpdateWrapper(JSObject* aNewObject, const JSObject* aOldObject) {
+    MOZ_ASSERT(js::GetObjectZoneFromAnyThread(aNewObject) ==
+               js::GetObjectZoneFromAnyThread(aOldObject));
     if (mWrapper) {
       MOZ_ASSERT(mWrapper == aOldObject);
       mWrapper = aNewObject;
@@ -293,8 +296,8 @@ class nsWrapperCache {
       return;
     }
 
-    GetWrapper();  // Read barrier for incremental GC.
-    HoldJSObjects(aScriptObjectHolder, aTracer);
+    JSObject* wrapper = GetWrapper();  // Read barrier for incremental GC.
+    HoldJSObjects(aScriptObjectHolder, aTracer, JS::GetObjectZone(wrapper));
     SetPreservingWrapper(true);
 #ifdef DEBUG
     // Make sure the cycle collector will be able to traverse to the wrapper.
@@ -341,7 +344,8 @@ class nsWrapperCache {
     mFlags &= ~aFlagsToUnset;
   }
 
-  void HoldJSObjects(void* aScriptObjectHolder, nsScriptObjectTracer* aTracer);
+  void HoldJSObjects(void* aScriptObjectHolder, nsScriptObjectTracer* aTracer,
+                     JS::Zone* aZone);
 
 #ifdef DEBUG
  public:

js/src/jsfriendapi.cpp

@@ -1543,6 +1543,6 @@ bool js::AddListFormatConstructor(JSContext* cx, JS::HandleObject intl) {
 
 #endif  // !JS_HAS_INTL_API
 
-JS_FRIEND_API JS::Zone* js::GetObjectZoneFromAnyThread(JSObject* obj) {
+JS_FRIEND_API JS::Zone* js::GetObjectZoneFromAnyThread(const JSObject* obj) {
   return MaybeForwarded(obj)->zoneFromAnyThread();
 }

js/src/jsfriendapi.h

@@ -2692,7 +2692,7 @@ extern JS_FRIEND_API void SetPerformanceHint(JSContext* cx,
 
 } /* namespace gc */
 
-extern JS_FRIEND_API JS::Zone* GetObjectZoneFromAnyThread(JSObject* obj);
+extern JS_FRIEND_API JS::Zone* GetObjectZoneFromAnyThread(const JSObject* obj);
 
 } /* namespace js */
 

xpcom/base/CycleCollectedJSRuntime.cpp

@@ -1244,7 +1244,8 @@ void CycleCollectedJSRuntime::TraceNativeGrayRoots(JSTracer* aTracer) {
 }
 
 void CycleCollectedJSRuntime::AddJSHolder(void* aHolder,
-                                          nsScriptObjectTracer* aTracer) {
+                                          nsScriptObjectTracer* aTracer,
+                                          JS::Zone* aZone) {
   mJSHolders.Put(aHolder, aTracer);
 }
 

xpcom/base/CycleCollectedJSRuntime.h

@@ -273,7 +273,8 @@ class CycleCollectedJSRuntime {
   }
 
  public:
-  void AddJSHolder(void* aHolder, nsScriptObjectTracer* aTracer);
+  void AddJSHolder(void* aHolder, nsScriptObjectTracer* aTracer,
+                   JS::Zone* aZone);
   void RemoveJSHolder(void* aHolder);
 #ifdef DEBUG
   void AssertNoObjectsToTrace(void* aPossibleJSHolder);

xpcom/base/HoldDropJSObjects.cpp

@@ -12,10 +12,11 @@
 namespace mozilla {
 namespace cyclecollector {
 
-void HoldJSObjectsImpl(void* aHolder, nsScriptObjectTracer* aTracer) {
+void HoldJSObjectsImpl(void* aHolder, nsScriptObjectTracer* aTracer,
+                       JS::Zone* aZone) {
   CycleCollectedJSRuntime* rt = CycleCollectedJSRuntime::Get();
   MOZ_ASSERT(rt, "Should have a CycleCollectedJSRuntime by now");
-  rt->AddJSHolder(aHolder, aTracer);
+  rt->AddJSHolder(aHolder, aTracer, aZone);
 }
 
 void HoldJSObjectsImpl(nsISupports* aHolder) {

xpcom/base/HoldDropJSObjects.h

@@ -17,7 +17,8 @@ class nsScriptObjectTracer;
 namespace mozilla {
 namespace cyclecollector {
 
-void HoldJSObjectsImpl(void* aHolder, nsScriptObjectTracer* aTracer);
+void HoldJSObjectsImpl(void* aHolder, nsScriptObjectTracer* aTracer,
+                       JS::Zone* aZone = nullptr);
 void HoldJSObjectsImpl(nsISupports* aHolder);
 void DropJSObjectsImpl(void* aHolder);
 void DropJSObjectsImpl(nsISupports* aHolder);