// Copyright 2010 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef V8_VM_STATE_H_
#define V8_VM_STATE_H_

#include "src/allocation.h"
#include "src/counters.h"

namespace v8 {
namespace internal {

// Logging and profiling.  A StateTag represents a possible state of
// the VM. The logger maintains a stack of these. Creating a VMState
// object enters a state by pushing on the stack, and destroying a
// VMState object leaves a state by popping the current state from the
// stack.
template <StateTag Tag>
class VMState BASE_EMBEDDED {
 public:
  explicit inline VMState(Isolate* isolate);
  inline ~VMState();

 private:
  Isolate* isolate_;
  StateTag previous_tag_;
};


class ExternalCallbackScope BASE_EMBEDDED {
 public:
  inline ExternalCallbackScope(Isolate* isolate, Address callback);
  inline ~ExternalCallbackScope();
  Address callback() { return callback_; }
  Address* callback_entrypoint_address() {
    if (callback_ == kNullAddress) return nullptr;
#if USES_FUNCTION_DESCRIPTORS
    return FUNCTION_ENTRYPOINT_ADDRESS(callback_);
#else
    return &callback_;
#endif
  }
  ExternalCallbackScope* previous() { return previous_scope_; }
  inline Address scope_address();

 private:
  Isolate* isolate_;
  Address callback_;
  ExternalCallbackScope* previous_scope_;
#ifdef USE_SIMULATOR
  Address scope_address_;
#endif
};

}  // namespace internal
}  // namespace v8


#endif  // V8_VM_STATE_H_