src/hotspot/share/gc/serial/defNewGeneration.inline.hpp

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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#ifndef SHARE_VM_GC_SERIAL_DEFNEWGENERATION_INLINE_HPP
#define SHARE_VM_GC_SERIAL_DEFNEWGENERATION_INLINE_HPP

#include "gc/serial/defNewGeneration.hpp"
#include "gc/shared/cardTableRS.hpp"
#include "gc/shared/genCollectedHeap.hpp"
#include "gc/shared/genOopClosures.inline.hpp"
#include "gc/shared/space.inline.hpp"
#include "oops/access.inline.hpp"

// Methods of protected closure types

template <class T>
inline void DefNewGeneration::KeepAliveClosure::do_oop_work(T* p) {
#ifdef ASSERT
  {
    // We never expect to see a null reference being processed
    // as a weak reference.
    oop obj = RawAccess<IS_NOT_NULL>::oop_load(p);
    assert (oopDesc::is_oop(obj), "expected an oop while scanning weak refs");
  }
#endif // ASSERT

  Devirtualizer::do_oop_no_verify(_cl, p);

  // Card marking is trickier for weak refs.
  // This oop is a 'next' field which was filled in while we
  // were discovering weak references. While we might not need
  // to take a special action to keep this reference alive, we
  // will need to dirty a card as the field was modified.
  //
  // Alternatively, we could create a method which iterates through
  // each generation, allowing them in turn to examine the modified
  // field.
  //
  // We could check that p is also in the old generation, but
  // dirty cards in the young gen are never scanned, so the
  // extra check probably isn't worthwhile.
  if (GenCollectedHeap::heap()->is_in_reserved(p)) {
    oop obj = RawAccess<IS_NOT_NULL>::oop_load(p);
    _rs->inline_write_ref_field_gc(p, obj);
  }
}

template <class T>
inline void DefNewGeneration::FastKeepAliveClosure::do_oop_work(T* p) {
#ifdef ASSERT
  {
    // We never expect to see a null reference being processed
    // as a weak reference.
    oop obj = RawAccess<IS_NOT_NULL>::oop_load(p);
    assert (oopDesc::is_oop(obj), "expected an oop while scanning weak refs");
  }
#endif // ASSERT

  Devirtualizer::do_oop_no_verify(_cl, p);

  // Optimized for Defnew generation if it's the youngest generation:
  // we set a younger_gen card if we have an older->youngest
  // generation pointer.
  oop obj = RawAccess<IS_NOT_NULL>::oop_load(p);
  if (((HeapWord*)obj < _boundary) && GenCollectedHeap::heap()->is_in_reserved(p)) {
    _rs->inline_write_ref_field_gc(p, obj);
  }
}

template <typename OopClosureType>
void DefNewGeneration::oop_since_save_marks_iterate(OopClosureType* cl) {
  cl->set_generation(this);
  eden()->oop_since_save_marks_iterate(cl);
  to()->oop_since_save_marks_iterate(cl);
  from()->oop_since_save_marks_iterate(cl);
  cl->reset_generation();
  save_marks();
}

#endif // SHARE_VM_GC_SERIAL_DEFNEWGENERATION_INLINE_HPP