view src/share/vm/oops/klassKlass.hpp @ 3979:4dfb2df418f2

6484982: G1: process references during evacuation pauses Summary: G1 now uses two reference processors - one is used by concurrent marking and the other is used by STW GCs (both full and incremental evacuation pauses). In an evacuation pause, the reference processor is embedded into the closures used to scan objects. Doing so causes causes reference objects to be 'discovered' by the reference processor. At the end of the evacuation pause, these discovered reference objects are processed - preserving (and copying) referent objects (and their reachable graphs) as appropriate. Reviewed-by: ysr, jwilhelm, brutisso, stefank, tonyp
author johnc
date Thu, 22 Sep 2011 10:57:37 -0700
parents f95d63e2154a
children dddcdb7ae209
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/*
 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#ifndef SHARE_VM_OOPS_KLASSKLASS_HPP
#define SHARE_VM_OOPS_KLASSKLASS_HPP

#include "memory/oopFactory.hpp"
#include "oops/klass.hpp"
#include "oops/klassOop.hpp"

// A klassKlass serves as the fix point of the klass chain.
// The klass of klassKlass is itself.

class klassKlass: public Klass {
  friend class VMStructs;
 private:
  juint    _alloc_size;        // allocation profiling support
 public:
  // Testing
  bool oop_is_klass()  const { return true; }
  bool is_leaf_class() const { return true; }

  // Sizing
  int oop_size(oop obj) const;
  int klass_oop_size() const { return object_size(); }

  // Allocation
  DEFINE_ALLOCATE_PERMANENT(klassKlass);
  static klassOop create_klass(TRAPS );

  // Casting from klassOop
  static klassKlass* cast(klassOop k) {
    assert(k->klass_part()->oop_is_klass(), "cast to klassKlass");
    return (klassKlass*) k->klass_part();
  }

  // Sizing
  static int header_size()  { return oopDesc::header_size() + sizeof(klassKlass)/HeapWordSize; }
  int object_size() const   { return align_object_size(header_size()); }

  // Garbage collection
  void oop_follow_contents(oop obj);
  int  oop_adjust_pointers(oop obj);

  // Parallel Scavenge and Parallel Old
  PARALLEL_GC_DECLS

  // Iterators
  int  oop_oop_iterate(oop obj, OopClosure* blk);
  int  oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr);

  // Allocation profiling support
  juint alloc_size() const              { return _alloc_size; }
  void set_alloc_size(juint n)          { _alloc_size = n; }

  // Printing
  void oop_print_value_on(oop obj, outputStream* st);
  void oop_print_on      (oop obj, outputStream* st);

  // Verification
  const char* internal_name() const;
  void oop_verify_on(oop obj, outputStream* st);
};

#endif // SHARE_VM_OOPS_KLASSKLASS_HPP