Implement a garbage collection prologue and epilogue callback mechanism.

runtime/vm/isolate.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 VM_ISOLATE_H_
 #define VM_ISOLATE_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/thread.h"
+#include "vm/gc_callbacks.h"
 #include "vm/store_buffer.h"
 #include "vm/timer.h"
 
 namespace dart {
 
 // Forward declarations.
 class ApiState;
 class CodeIndexTable;
 class Debugger;
 class HandleScope;
@@ skipping 204 matching lines @@
   void set_ast_node_id(int value) { ast_node_id_ = value; }
 
   Debugger* debugger() const { return debugger_; }
 
   static void SetCreateCallback(Dart_IsolateCreateCallback cback);
   static Dart_IsolateCreateCallback CreateCallback();
 
   static void SetInterruptCallback(Dart_IsolateInterruptCallback cback);
   static Dart_IsolateInterruptCallback InterruptCallback();
 
+  GcPrologueCallbacks& gc_prologue_callbacks() {
+    return gc_prologue_callbacks_;
+  }
+
+  GcEpilogueCallbacks& gc_epilogue_callbacks() {
+    return gc_epilogue_callbacks_;
+  }
+
  private:
   Isolate();
 
   void BuildName(const char* name_prefix);
   void PrintInvokedFunctions();
 
   static uword GetSpecifiedStackSize();
 
   static const uword kStackSizeBuffer = (128 * KB);
   static const uword kDefaultStackSize = (1 * MB);
@@ skipping 21 matching lines @@
   StubCode* stub_code_;
   CodeIndexTable* code_index_table_;
   Debugger* debugger_;
   LongJump* long_jump_base_;
   TimerList timer_list_;
   intptr_t ast_node_id_;
   Mutex* mutex_;  // protects stack_limit_ and saved_stack_limit_.
   uword stack_limit_;
   uword saved_stack_limit_;
   MessageHandler* message_handler_;
+  GcPrologueCallbacks gc_prologue_callbacks_;
+  GcEpilogueCallbacks gc_epilogue_callbacks_;
 
   static Dart_IsolateCreateCallback create_callback_;
   static Dart_IsolateInterruptCallback interrupt_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(Isolate);
 };
 
 }  // namespace dart
 
 #endif  // VM_ISOLATE_H_