[vm, gc] Require a safepoint for heap iteration.

runtime/vm/isolate.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/isolate.h"
 
 #include "include/dart_api.h"
 #include "include/dart_native_api.h"
 #include "platform/assert.h"
 #include "platform/text_buffer.h"
@@ skipping 1447 matching lines @@
     ASSERT(thread->isolate() == isolate);
     StackZone zone(thread);
     HandleScope handle_scope(thread);
 // TODO(27003): Enable for precompiled.
 #if defined(DEBUG) && !defined(DART_PRECOMPILED_RUNTIME)
     if (!isolate->HasAttemptedReload()) {
       // For this verification we need to stop the background compiler earlier.
       // This would otherwise happen in Dart::ShowdownIsolate.
       isolate->StopBackgroundCompiler();
       isolate->heap()->CollectAllGarbage();
+      HeapIterationScope iteration(thread);
       VerifyCanonicalVisitor check_canonical(thread);
-      isolate->heap()->IterateObjects(&check_canonical);
+      iteration.IterateObjects(&check_canonical);
     }
 #endif  // DEBUG
     const Error& error = Error::Handle(thread->sticky_error());
     if (!error.IsNull() && !error.IsUnwindError()) {
       OS::PrintErr("in ShutdownIsolate: %s\n", error.ToErrorCString());
     }
     Dart::RunShutdownCallback();
   }
   // Shut the isolate down.
   Dart::ShutdownIsolate(isolate);
@@ skipping 251 matching lines @@
 }
 
 Dart_IsolateCreateCallback Isolate::create_callback_ = NULL;
 Dart_IsolateShutdownCallback Isolate::shutdown_callback_ = NULL;
 Dart_IsolateCleanupCallback Isolate::cleanup_callback_ = NULL;
 
 Monitor* Isolate::isolates_list_monitor_ = NULL;
 Isolate* Isolate::isolates_list_head_ = NULL;
 bool Isolate::creation_enabled_ = false;
 
-void Isolate::IterateObjectPointers(ObjectPointerVisitor* visitor,
-                                    bool validate_frames) {
-  HeapIterationScope heap_iteration_scope;
-  VisitObjectPointers(visitor, validate_frames);
-}
-
-void Isolate::IterateStackPointers(ObjectPointerVisitor* visitor,
-                                   bool validate_frames) {
-  HeapIterationScope heap_iteration_scope;
-  VisitStackPointers(visitor, validate_frames);
-}
-
 void Isolate::VisitObjectPointers(ObjectPointerVisitor* visitor,
                                   bool validate_frames) {
   ASSERT(visitor != NULL);
 
   // Visit objects in the object store.
   object_store()->VisitObjectPointers(visitor);
 
   // Visit objects in the class table.
   class_table()->VisitObjectPointers(visitor);
 
@@ skipping 1090 matching lines @@
 void IsolateSpawnState::DecrementSpawnCount() {
   ASSERT(spawn_count_monitor_ != NULL);
   ASSERT(spawn_count_ != NULL);
   MonitorLocker ml(spawn_count_monitor_);
   ASSERT(*spawn_count_ > 0);
   *spawn_count_ = *spawn_count_ - 1;
   ml.Notify();
 }
 
 }  // namespace dart