Add more safe points in compiler

runtime/vm/scavenger.h

 // Copyright (c) 2012, 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.
 
 #ifndef RUNTIME_VM_SCAVENGER_H_
 #define RUNTIME_VM_SCAVENGER_H_
 
 #include "platform/assert.h"
 #include "platform/utils.h"
 #include "vm/dart.h"
@@ skipping 180 matching lines @@
   void PrintToJSONObject(JSONObject* object) const;
 #endif  // !PRODUCT
 
   void AllocateExternal(intptr_t size);
   void FreeExternal(intptr_t size);
 
  private:
   // Ids for time and data records in Heap::GCStats.
   enum {
     // Time
-    kVisitIsolateRoots = 0,
-    kIterateStoreBuffers = 1,
-    kProcessToSpace = 2,
-    kIterateWeaks = 3,
+    kDummyScavengeTime = 0,
+    kSafePoint = 1,
+    kVisitIsolateRoots = 2,
+    kIterateStoreBuffers = 3,
+    kProcessToSpace = 4,
+    kIterateWeaks = 5,
     // Data
     kStoreBufferEntries = 0,
     kDataUnused1 = 1,
     kDataUnused2 = 2,
     kToKBAfterStoreBuffer = 3
   };
 
   uword FirstObjectStart() const { return to_->start() | object_alignment_; }
   SemiSpace* Prologue(Isolate* isolate, bool invoke_api_callbacks);
   void IterateStoreBuffers(Isolate* isolate, ScavengerVisitor* visitor);
@@ skipping 80 matching lines @@
 
   friend class ScavengerVisitor;
   friend class ScavengerWeakVisitor;
 
   DISALLOW_COPY_AND_ASSIGN(Scavenger);
 };
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_SCAVENGER_H_