frames.h.svn-base

Google浏览器V8内核代码

 public:
  virtual Type type() const { return EXIT_DEBUG; }

  virtual Code* FindCode() const;

  static ExitDebugFrame* cast(StackFrame* frame) {
    ASSERT(frame->is_exit_debug());
    return static_cast<ExitDebugFrame*>(frame);
  }

 protected:
  explicit ExitDebugFrame(StackFrameIterator* iterator)
      : ExitFrame(iterator) { }

 private:
  friend class StackFrameIterator;
};


class StandardFrame: public StackFrame {
 public:
  // Testers.
  virtual bool is_standard() const { return true; }

  // Accessors.
  inline Object* context() const;

  // Access the expressions in the stack frame including locals.
  inline Object* GetExpression(int index) const;
  inline void SetExpression(int index, Object* value);
  int ComputeExpressionsCount() const;

  static StandardFrame* cast(StackFrame* frame) {
    ASSERT(frame->is_standard());
    return static_cast<StandardFrame*>(frame);
  }

 protected:
  explicit StandardFrame(StackFrameIterator* iterator)
      : StackFrame(iterator) { }

  virtual Type GetCallerState(State* state) const;

  // Accessors.
  inline Address caller_sp() const;
  inline Address caller_fp() const;
  inline Address caller_pc() const;

  // Computes the address of the PC field in the standard frame given
  // by the provided frame pointer.
  static inline Address ComputePCAddress(Address fp);

  // Iterate over expression stack including stack handlers, locals,
  // and parts of the fixed part including context and code fields.
  void IterateExpressions(ObjectVisitor* v) const;

  // Returns the address of the n'th expression stack element.
  Address GetExpressionAddress(int n) const;

  // Determines if the n'th expression stack element is in a stack
  // handler or not. Requires traversing all handlers in this frame.
  bool IsExpressionInsideHandler(int n) const;

  // Determines if the standard frame for the given frame pointer is
  // an arguments adaptor frame.
  static inline bool IsArgumentsAdaptorFrame(Address fp);

  // Determines if the standard frame for the given program counter is
  // a construct trampoline.
  static inline bool IsConstructTrampolineFrame(Address pc);

 private:
  friend class StackFrame;
};


class JavaScriptFrame: public StandardFrame {
 public:
  virtual Type type() const { return JAVA_SCRIPT; }

  // Accessors.
  inline Object* function() const;
  inline Object* receiver() const;
  inline void set_receiver(Object* value);

  // Access the parameters.
  Object* GetParameter(int index) const;
  int ComputeParametersCount() const;

  // Temporary way of getting access to the number of parameters
  // passed on the stack by the caller. Once argument adaptor frames
  // has been introduced on ARM, this number will always match the
  // computed parameters count.
  int GetProvidedParametersCount() const;

  // Check if this frame is a constructor frame invoked through
  // 'new'. The operation may involve digging through a few stack
  // frames to account for arguments adaptors.
  bool IsConstructor() const;

  // Check if this frame has "adapted" arguments in the sense that the
  // actual passed arguments are available in an arguments adaptor
  // frame below it on the stack.
  inline bool has_adapted_arguments() const;

  // Garbage colletion support.
  virtual void Iterate(ObjectVisitor* v) const;

  // Printing support.
  virtual void Print(StringStream* accumulator,
                     PrintMode mode,
                     int index) const;

  // Determine the code for the frame.
  virtual Code* FindCode() const;

  static JavaScriptFrame* cast(StackFrame* frame) {
    ASSERT(frame->is_java_script());
    return static_cast<JavaScriptFrame*>(frame);
  }

 protected:
  explicit JavaScriptFrame(StackFrameIterator* iterator)
      : StandardFrame(iterator) { }

  virtual Address GetCallerStackPointer() const;

 private:
  friend class StackFrameIterator;
};


// Arguments adaptor frames are automatically inserted below
// JavaScript frames when the actual number of parameters does not
// match the formal number of parameters.
class ArgumentsAdaptorFrame: public JavaScriptFrame {
 public:
  // This sentinel value is temporarily used to distinguish arguments
  // adaptor frames from ordinary JavaScript frames. If a frame has
  // the sentinel as its context, it is an arguments adaptor frame. It
  // must be tagged as a small integer to avoid GC issues. Crud.
  enum {
    SENTINEL = (1 << kSmiTagSize) | kSmiTag
  };

  virtual Type type() const { return ARGUMENTS_ADAPTOR; }

  // Determine the code for the frame.
  virtual Code* FindCode() const;

  static ArgumentsAdaptorFrame* cast(StackFrame* frame) {
    ASSERT(frame->is_arguments_adaptor());
    return static_cast<ArgumentsAdaptorFrame*>(frame);
  }

  // Printing support.
  virtual void Print(StringStream* accumulator,
                     PrintMode mode,
                     int index) const;
 protected:
  explicit ArgumentsAdaptorFrame(StackFrameIterator* iterator)
      : JavaScriptFrame(iterator) { }

  virtual Address GetCallerStackPointer() const;

 private:
  friend class StackFrameIterator;
};


class InternalFrame: public StandardFrame {
 public:
  virtual Type type() const { return INTERNAL; }

  // Returns if this frame is a special trampoline frame introduced by
  // the construct trampoline. NOTE: We should consider introducing a
  // special stack frame type for this.
  inline bool is_construct_trampoline() const;

  // Garbage colletion support.
  virtual void Iterate(ObjectVisitor* v) const;

  // Determine the code for the frame.
  virtual Code* FindCode() const;

  static InternalFrame* cast(StackFrame* frame) {
    ASSERT(frame->is_internal());
    return static_cast<InternalFrame*>(frame);
  }

 protected:
  explicit InternalFrame(StackFrameIterator* iterator)
      : StandardFrame(iterator) { }

  virtual Address GetCallerStackPointer() const;

 private:
  friend class StackFrameIterator;
};


class StackFrameIterator BASE_EMBEDDED {
 public:
  // An iterator that iterates over the current thread's stack.
  StackFrameIterator();

  // An iterator that iterates over a given thread's stack.
  explicit StackFrameIterator(ThreadLocalTop* thread);

  StackFrame* frame() const {
    ASSERT(!done());
    return frame_;
  }

  bool done() const { return frame_ == NULL; }
  void Advance();

  // Go back to the first frame.
  void Reset();

 private:
#define DECLARE_SINGLETON(ignore, type) type type##_;
  STACK_FRAME_TYPE_LIST(DECLARE_SINGLETON)
#undef DECLARE_SINGLETON
  StackFrame* frame_;
  StackHandler* handler_;
  ThreadLocalTop* thread_;

  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);

  friend class StackFrame;
  DISALLOW_COPY_AND_ASSIGN(StackFrameIterator);
};


// Iterator that supports iterating through all JavaScript frames.
class JavaScriptFrameIterator BASE_EMBEDDED {
 public:
  JavaScriptFrameIterator() { if (!done()) Advance(); }

  explicit JavaScriptFrameIterator(ThreadLocalTop* thread) : iterator_(thread) {
    if (!done()) Advance();
  }

  // Skip frames until the frame with the given id is reached.
  explicit JavaScriptFrameIterator(StackFrame::Id id);

  inline JavaScriptFrame* frame() const;

  bool done() const { return iterator_.done(); }
  void Advance();

  // Advance to the frame holding the arguments for the current
  // frame. This only affects the current frame if it has adapted
  // arguments.
  void AdvanceToArgumentsFrame();

  // Go back to the first frame.
  void Reset();

 private:
  StackFrameIterator iterator_;
};


class StackFrameLocator BASE_EMBEDDED {
 public:
  // Find the nth JavaScript frame on the stack. The caller must
  // guarantee that such a frame exists.
  JavaScriptFrame* FindJavaScriptFrame(int n);

 private:
  StackFrameIterator iterator_;
};


} }  // namespace v8::internal

#endif  // V8_FRAMES_H_