1/*
2 * Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
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23 */
24
25#ifndef SHARE_VM_GC_PARALLEL_IMMUTABLESPACE_HPP
26#define SHARE_VM_GC_PARALLEL_IMMUTABLESPACE_HPP
27
28#include "memory/iterator.hpp"
29
30// An ImmutableSpace is a viewport into a contiguous range
31// (or subrange) of previously allocated objects.
32
33// Invariant: bottom() and end() are on page_size boundaries and
34// bottom() <= end()
35
36class ImmutableSpace: public CHeapObj<mtGC> {
37  friend class VMStructs;
38 protected:
39  HeapWord* _bottom;
40  HeapWord* _end;
41
42 public:
43  ImmutableSpace()                   { _bottom = NULL; _end = NULL;  }
44  HeapWord* bottom() const           { return _bottom;               }
45  HeapWord* end() const              { return _end;                  }
46
47  MemRegion region() const { return MemRegion(bottom(), end()); }
48
49  // Initialization
50  void initialize(MemRegion mr);
51
52  bool contains(const void* p) const { return _bottom <= p && p < _end; }
53
54  // Size computations.  Sizes are in bytes.
55  size_t capacity_in_bytes() const            { return capacity_in_words() * HeapWordSize; }
56
57  // Size computations.  Sizes are in heapwords.
58  size_t capacity_in_words() const                { return pointer_delta(end(), bottom()); }
59  virtual size_t capacity_in_words(Thread*) const { return capacity_in_words(); }
60
61  // Iteration.
62  virtual void oop_iterate(ExtendedOopClosure* cl);
63  virtual void object_iterate(ObjectClosure* cl);
64
65  // Debugging
66  virtual void print() const            PRODUCT_RETURN;
67  virtual void print_short() const      PRODUCT_RETURN;
68  virtual void verify();
69};
70
71#endif // SHARE_VM_GC_PARALLEL_IMMUTABLESPACE_HPP
72