src/hotspot/cpu/ppc/javaFrameAnchor_ppc.hpp

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#ifndef CPU_PPC_JAVAFRAMEANCHOR_PPC_HPP
#define CPU_PPC_JAVAFRAMEANCHOR_PPC_HPP

public:
  // Each arch must define reset, save, restore
  // These are used by objects that only care about:
  //  1 - initializing a new state (thread creation, javaCalls)
  //  2 - saving a current state (javaCalls)
  //  3 - restoring an old state (javaCalls)

  inline void clear(void) {
    // clearing _last_Java_sp must be first
    _last_Java_sp = nullptr;
    // fence?
    OrderAccess::release();
    _last_Java_pc = nullptr;
  }

  inline void set(intptr_t* sp, address pc) {
    _last_Java_pc = pc;
    OrderAccess::release();
    _last_Java_sp = sp;
  }

  void copy(JavaFrameAnchor* src) {
    // In order to make sure the transition state is valid for "this".
    // We must clear _last_Java_sp before copying the rest of the new data.
    //
    // Hack Alert: Temporary bugfix for 4717480/4721647
    // To act like previous version (pd_cache_state) don't null _last_Java_sp
    // unless the value is changing.
    if (_last_Java_sp != src->_last_Java_sp) {
      _last_Java_sp = nullptr;
      OrderAccess::release();
    }
    _last_Java_pc = src->_last_Java_pc;
    // Must be last so profiler will always see valid frame if has_last_frame() is true.
    OrderAccess::release();
    _last_Java_sp = src->_last_Java_sp;
  }

  // Always walkable.
  bool walkable(void) { return true; }
  // Never any thing to do since we are always walkable and can find address of return addresses.
  void make_walkable() { }

  intptr_t* last_Java_sp(void) const  { return _last_Java_sp; }

  address last_Java_pc(void)          { return _last_Java_pc; }

  intptr_t* last_Java_fp() const      { return *(intptr_t**)_last_Java_sp; }

  void set_last_Java_sp(intptr_t* sp) { OrderAccess::release(); _last_Java_sp = sp; }

#endif // CPU_PPC_JAVAFRAMEANCHOR_PPC_HPP