Get rid of Isolate::safe_stack_iterator_counter

src/frames.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 303 matching lines @@
 
   // Printing support.
   static void PrintIndex(StringStream* accumulator,
                          PrintMode mode,
                          int index);
 
   // Get the top handler from the current stack iterator.
   inline StackHandler* top_handler() const;
 
   // Compute the stack frame type for the given state.
-  static Type ComputeType(Isolate* isolate, State* state);
+  static Type ComputeType(const StackFrameIterator* iterator, State* state);
+
+#ifdef DEBUG
+  bool is_safe_iteration() const;
+#endif
 
  private:
   const StackFrameIterator* iterator_;
   Isolate* isolate_;
   State state_;
 
   // Fill in the state of the calling frame.
   virtual void ComputeCallerState(State* state) const = 0;
 
   // Get the type and the state of the calling frame.
@@ skipping 440 matching lines @@
 
 
 class StackFrameIterator BASE_EMBEDDED {
  public:
   // An iterator that iterates over the isolate's current thread's stack,
   explicit StackFrameIterator(Isolate* isolate);
 
   // An iterator that iterates over a given thread's stack.
   StackFrameIterator(Isolate* isolate, ThreadLocalTop* t);
 
-  // An iterator that can start from a given FP address.
-  // If use_top, then work as usual, if fp isn't NULL, use it,
-  // otherwise, do nothing.
-  StackFrameIterator(Isolate* isolate, bool use_top, Address fp, Address sp);
-
   StackFrame* frame() const {
     ASSERT(!done());
     return frame_;
   }
 
   Isolate* isolate() const { return isolate_; }
 
   bool done() const { return frame_ == NULL; }
   void Advance() { (this->*advance_)(); }
 
  private:
+  // An iterator that can start from a given FP address.
+  // If use_top, then work as usual, if fp isn't NULL, use it,
+  // otherwise, do nothing. This constructor is used to create
+  // StackFrameIterator for "safe" stack iteration.
+  StackFrameIterator(Isolate* isolate, bool use_top, Address fp, Address sp);
+
   // Go back to the first frame.
   void Reset();
 
   Isolate* isolate_;
 #define DECLARE_SINGLETON(ignore, type) type type##_;
   STACK_FRAME_TYPE_LIST(DECLARE_SINGLETON)
 #undef DECLARE_SINGLETON
   StackFrame* frame_;
   StackHandler* handler_;
   ThreadLocalTop* thread_;
   Address fp_;
   Address sp_;
   void (StackFrameIterator::*advance_)();
+  const bool is_safe_iterator_;

[loislo, 2013/06/25 09:36:26]

I'd call it 'can_use_heap_objects_'

[yurys, 2013/06/25 09:44:17]

Done. Thank you.

 
   StackHandler* handler() const {
     ASSERT(!done());
     return handler_;
   }
 
   // Get the type-specific frame singleton in a given state.
   StackFrame* SingletonFor(StackFrame::Type type, StackFrame::State* state);
   // A helper function, can return a NULL pointer.
   StackFrame* SingletonFor(StackFrame::Type type);
@@ skipping 48 matching lines @@
  public:
   SafeStackFrameIterator(Isolate* isolate,
                          Address fp, Address sp,
                          Address low_bound, Address high_bound);
 
   inline JavaScriptFrame* frame() const;
 
   bool done() const { return iteration_done_ || iterator_.done(); }
   void Advance();
 
-  static bool is_active(Isolate* isolate);
-
  private:
   void AdvanceOneFrame();
 
   static bool IsWithinBounds(
       Address low_bound, Address high_bound, Address addr) {
     return low_bound <= addr && addr <= high_bound;
   }
 
   class StackAddressValidator {
    public:
@@ skipping 20 matching lines @@
 
   bool IsValidStackAddress(Address addr) const {
     return stack_validator_.IsValid(addr);
   }
   bool CanIterateHandles(StackFrame* frame, StackHandler* handler);
   bool IsValidFrame(StackFrame* frame) const;
   bool IsValidCaller(StackFrame* frame);
   static bool IsValidTop(Isolate* isolate,
                          Address low_bound, Address high_bound);
 
-  // This is a nasty hack to make sure the active count is incremented
-  // before the constructor for the embedded iterator is invoked. This
-  // is needed because the constructor will start looking at frames
-  // right away and we need to make sure it doesn't start inspecting
-  // heap objects.
-  class ActiveCountMaintainer BASE_EMBEDDED {
-   public:
-    explicit ActiveCountMaintainer(Isolate* isolate);
-    ~ActiveCountMaintainer();
-   private:
-    Isolate* isolate_;
-  };
-
-  ActiveCountMaintainer maintainer_;
   StackAddressValidator stack_validator_;
   const bool is_valid_top_;
   const bool is_valid_fp_;
   bool iteration_done_;
   StackFrameIterator iterator_;
 };
 
 
 class StackFrameLocator BASE_EMBEDDED {
  public:
   explicit StackFrameLocator(Isolate* isolate) : iterator_(isolate) {}
 
   // Find the nth JavaScript frame on the stack. The caller must
   // guarantee that such a frame exists.
   JavaScriptFrame* FindJavaScriptFrame(int n);
 
  private:
   StackFrameIterator iterator_;
 };
 
 
 // Reads all frames on the current stack and copies them into the current
 // zone memory.
 Vector<StackFrame*> CreateStackMap(Isolate* isolate, Zone* zone);
 
 } }  // namespace v8::internal
 
 #endif  // V8_FRAMES_H_