Rip out infrastructure for deferred stack trace formatting.

R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/19971002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15816 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/heap-inl.h

@@ -712,19 +712,6 @@ void ExternalStringTable::ShrinkNewStrings(int position) {
 }
 
 
-void ErrorObjectList::Add(JSObject* object) {
-  list_.Add(object);
-}
-
-
-void ErrorObjectList::Iterate(ObjectVisitor* v) {
-  if (!list_.is_empty()) {
-    Object** start = &list_[0];
-    v->VisitPointers(start, start + list_.length());
-  }
-}
-
-
 void Heap::ClearInstanceofCache() {
   set_instanceof_cache_function(the_hole_value());
 }

src/heap.cc

@@ -583,8 +583,6 @@ void Heap::GarbageCollectionEpilogue() {
 #ifdef ENABLE_DEBUGGER_SUPPORT
   isolate_->debug()->AfterGarbageCollection();
 #endif  // ENABLE_DEBUGGER_SUPPORT
-
-  error_object_list_.DeferredFormatStackTrace(isolate());
 }
 
 
@@ -1428,8 +1426,6 @@ void Heap::Scavenge() {
   UpdateNewSpaceReferencesInExternalStringTable(
       &UpdateNewSpaceReferenceInExternalStringTableEntry);
 
-  error_object_list_.UpdateReferencesInNewSpace(this);
-
   promotion_queue_.Destroy();
 
   if (!FLAG_watch_ic_patching) {
@@ -6575,7 +6571,6 @@ void Heap::IterateWeakRoots(ObjectVisitor* v, VisitMode mode) {
       mode != VISIT_ALL_IN_SWEEP_NEWSPACE) {
     // Scavenge collections have special processing for this.
     external_string_table_.Iterate(v);
-    error_object_list_.Iterate(v);
   }
   v->Synchronize(VisitorSynchronization::kExternalStringsTable);
 }
@@ -6975,8 +6970,6 @@ void Heap::TearDown() {
 
   external_string_table_.TearDown();
 
-  error_object_list_.TearDown();
-
   new_space_.TearDown();
 
   if (old_pointer_space_ != NULL) {
@@ -7929,120 +7922,6 @@ void ExternalStringTable::TearDown() {
 }
 
 
-// Update all references.
-void ErrorObjectList::UpdateReferences() {
-  for (int i = 0; i < list_.length(); i++) {
-    HeapObject* object = HeapObject::cast(list_[i]);
-    MapWord first_word = object->map_word();
-    if (first_word.IsForwardingAddress()) {
-      list_[i] = first_word.ToForwardingAddress();
-    }
-  }
-}
-
-
-// Unforwarded objects in new space are dead and removed from the list.
-void ErrorObjectList::UpdateReferencesInNewSpace(Heap* heap) {
-  if (list_.is_empty()) return;
-  if (!nested_) {
-    int write_index = 0;
-    for (int i = 0; i < list_.length(); i++) {
-      MapWord first_word = HeapObject::cast(list_[i])->map_word();
-      if (first_word.IsForwardingAddress()) {
-        list_[write_index++] = first_word.ToForwardingAddress();
-      }
-    }
-    list_.Rewind(write_index);
-  } else {
-    // If a GC is triggered during DeferredFormatStackTrace, we do not move
-    // objects in the list, just remove dead ones, as to not confuse the
-    // loop in DeferredFormatStackTrace.
-    for (int i = 0; i < list_.length(); i++) {
-      MapWord first_word = HeapObject::cast(list_[i])->map_word();
-      list_[i] = first_word.IsForwardingAddress()
-                     ? first_word.ToForwardingAddress()
-                     : heap->the_hole_value();
-    }
-  }
-}
-
-
-void ErrorObjectList::DeferredFormatStackTrace(Isolate* isolate) {
-  // If formatting the stack trace causes a GC, this method will be
-  // recursively called.  In that case, skip the recursive call, since
-  // the loop modifies the list while iterating over it.
-  if (nested_ || list_.is_empty() || isolate->has_pending_exception()) return;
-  nested_ = true;
-  HandleScope scope(isolate);
-  Handle<String> stack_key = isolate->factory()->stack_string();
-  int write_index = 0;
-  int budget = kBudgetPerGC;
-  for (int i = 0; i < list_.length(); i++) {
-    Object* object = list_[i];
-    JSFunction* getter_fun;
-
-    { DisallowHeapAllocation no_gc;
-      // Skip possible holes in the list.
-      if (object->IsTheHole()) continue;
-      if (isolate->heap()->InNewSpace(object) || budget == 0) {
-        list_[write_index++] = object;
-        continue;
-      }
-
-      // Check whether the stack property is backed by the original getter.
-      LookupResult lookup(isolate);
-      JSObject::cast(object)->LocalLookupRealNamedProperty(*stack_key, &lookup);
-      if (!lookup.IsFound() || lookup.type() != CALLBACKS) continue;
-      Object* callback = lookup.GetCallbackObject();
-      if (!callback->IsAccessorPair()) continue;
-      Object* getter_obj = AccessorPair::cast(callback)->getter();
-      if (!getter_obj->IsJSFunction()) continue;
-      getter_fun = JSFunction::cast(getter_obj);
-      String* key = isolate->heap()->hidden_stack_trace_string();
-      Object* value = getter_fun->GetHiddenProperty(key);
-      if (key != value) continue;
-    }
-
-    budget--;
-    HandleScope scope(isolate);
-    bool has_exception = false;
-#ifdef DEBUG
-    Handle<Map> map(HeapObject::cast(object)->map(), isolate);
-#endif
-    Handle<Object> object_handle(object, isolate);
-    Handle<Object> getter_handle(getter_fun, isolate);
-    Execution::Call(getter_handle, object_handle, 0, NULL, &has_exception);
-    ASSERT(*map == HeapObject::cast(*object_handle)->map());
-    if (has_exception) {
-      // Hit an exception (most likely a stack overflow).
-      // Wrap up this pass and retry after another GC.
-      isolate->clear_pending_exception();
-      // We use the handle since calling the getter might have caused a GC.
-      list_[write_index++] = *object_handle;
-      budget = 0;
-    }
-  }
-  list_.Rewind(write_index);
-  list_.Trim();
-  nested_ = false;
-}
-
-
-void ErrorObjectList::RemoveUnmarked(Heap* heap) {
-  for (int i = 0; i < list_.length(); i++) {
-    HeapObject* object = HeapObject::cast(list_[i]);
-    if (!Marking::MarkBitFrom(object).Get()) {
-      list_[i] = heap->the_hole_value();
-    }
-  }
-}
-
-
-void ErrorObjectList::TearDown() {
-  list_.Free();
-}
-
-
 void Heap::QueueMemoryChunkForFree(MemoryChunk* chunk) {
   chunk->set_next_chunk(chunks_queued_for_free_);
   chunks_queued_for_free_ = chunk;

src/heap.h

@@ -475,41 +475,6 @@ class ExternalStringTable {
 };
 
 
-// The stack property of an error object is implemented as a getter that
-// formats the attached raw stack trace into a string.  This raw stack trace
-// keeps code and function objects alive until the getter is called the first
-// time.  To release those objects, we call the getter after each GC for
-// newly tenured error objects that are kept in a list.
-class ErrorObjectList {
- public:
-  inline void Add(JSObject* object);
-
-  inline void Iterate(ObjectVisitor* v);
-
-  void TearDown();
-
-  void RemoveUnmarked(Heap* heap);
-
-  void DeferredFormatStackTrace(Isolate* isolate);
-
-  void UpdateReferences();
-
-  void UpdateReferencesInNewSpace(Heap* heap);
-
- private:
-  static const int kBudgetPerGC = 16;
-
-  ErrorObjectList() : nested_(false) { }
-
-  friend class Heap;
-
-  List<Object*> list_;
-  bool nested_;
-
-  DISALLOW_COPY_AND_ASSIGN(ErrorObjectList);
-};
-
-
 enum ArrayStorageAllocationMode {
   DONT_INITIALIZE_ARRAY_ELEMENTS,
   INITIALIZE_ARRAY_ELEMENTS_WITH_HOLE
@@ -1798,10 +1763,6 @@ class Heap {
     return &external_string_table_;
   }
 
-  ErrorObjectList* error_object_list() {
-    return &error_object_list_;
-  }
-
   // Returns the current sweep generation.
   int sweep_generation() {
     return sweep_generation_;
@@ -2406,8 +2367,6 @@ class Heap {
 
   ExternalStringTable external_string_table_;
 
-  ErrorObjectList error_object_list_;
-
   VisitorDispatchTable<ScavengingCallback> scavenging_visitors_table_;
 
   MemoryChunk* chunks_queued_for_free_;

src/mark-compact.cc

@@ -2396,7 +2396,6 @@ void MarkCompactCollector::AfterMarking() {
   string_table->ElementsRemoved(v.PointersRemoved());
   heap()->external_string_table_.Iterate(&v);
   heap()->external_string_table_.CleanUp();
-  heap()->error_object_list_.RemoveUnmarked(heap());
 
   // Process the weak references.
   MarkCompactWeakObjectRetainer mark_compact_object_retainer;
@@ -3463,9 +3462,6 @@ void MarkCompactCollector::EvacuateNewSpaceAndCandidates() {
   heap_->UpdateReferencesInExternalStringTable(
       &UpdateReferenceInExternalStringTableEntry);
 
-  // Update pointers in the new error object list.
-  heap_->error_object_list()->UpdateReferences();
-
   if (!FLAG_watch_ic_patching) {
     // Update JSFunction pointers from the runtime profiler.
     heap()->isolate()->runtime_profiler()->UpdateSamplesAfterCompact(