jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/shared/mutableSpace.hpp@37f87013dfd8

6711316: Open source the Garbage-First garbage collector
Summary: First mercurial integration of the code for the Garbage-First garbage collector.
Reviewed-by: apetrusenko, iveresov, jmasa, sgoldman, tonyp, ysr

     1 /*

     2  * Copyright 2001-2007 Sun Microsystems, Inc.  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.

    18  *

    19  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    20  * CA 95054 USA or visit www.sun.com if you need additional information or

    21  * have any questions.

    22  *

    23  */

    25 // A MutableSpace is a subtype of ImmutableSpace that supports the

    26 // concept of allocation. This includes the concepts that a space may

    27 // be only partially full, and the querry methods that go with such

    28 // an assumption.

    29 //

    30 // Invariant: (ImmutableSpace +) bottom() <= top() <= end()

    31 // top() is inclusive and end() is exclusive.

    33 class MutableSpace: public ImmutableSpace {

    34   friend class VMStructs;

    35  protected:

    36   HeapWord* _top;

    38  public:

    39   virtual ~MutableSpace()                  {}

    40   MutableSpace()                           { _top = NULL;    }

    41   // Accessors

    42   HeapWord* top() const                    { return _top;    }

    43   virtual void set_top(HeapWord* value)    { _top = value;   }

    45   HeapWord** top_addr()                    { return &_top; }

    46   HeapWord** end_addr()                    { return &_end; }

    48   virtual void set_bottom(HeapWord* value) { _bottom = value; }

    49   virtual void set_end(HeapWord* value)    { _end = value; }

    51   // Returns a subregion containing all objects in this space.

    52   MemRegion used_region() { return MemRegion(bottom(), top()); }

    54   // Initialization

    55   virtual void initialize(MemRegion mr, bool clear_space);

    56   virtual void clear();

    57   virtual void update() { }

    58   virtual void accumulate_statistics() { }

    60   // Overwrites the unused portion of this space. Note that some collectors

    61   // may use this "scratch" space during collections.

    62   virtual void mangle_unused_area() {

    63     mangle_region(MemRegion(_top, _end));

    64   }

    65   virtual void ensure_parsability() { }

    67   void mangle_region(MemRegion mr) {

    68     debug_only(Copy::fill_to_words(mr.start(), mr.word_size(), badHeapWord));

    69   }

    71   // Boolean querries.

    72   bool is_empty() const              { return used_in_words() == 0; }

    73   bool not_empty() const             { return used_in_words() > 0; }

    74   bool contains(const void* p) const { return _bottom <= p && p < _end; }

    76   // Size computations.  Sizes are in bytes.

    77   size_t used_in_bytes() const                { return used_in_words() * HeapWordSize; }

    78   size_t free_in_bytes() const                { return free_in_words() * HeapWordSize; }

    80   // Size computations.  Sizes are in heapwords.

    81   virtual size_t used_in_words() const                    { return pointer_delta(top(), bottom()); }

    82   virtual size_t free_in_words() const                    { return pointer_delta(end(),    top()); }

    83   virtual size_t tlab_capacity(Thread* thr) const         { return capacity_in_bytes();            }

    84   virtual size_t unsafe_max_tlab_alloc(Thread* thr) const { return free_in_bytes();                }

    86   // Allocation (return NULL if full)

    87   virtual HeapWord* allocate(size_t word_size);

    88   virtual HeapWord* cas_allocate(size_t word_size);

    89   // Optional deallocation. Used in NUMA-allocator.

    90   bool cas_deallocate(HeapWord *obj, size_t size);

    92   // Iteration.

    93   void oop_iterate(OopClosure* cl);

    94   void object_iterate(ObjectClosure* cl);

    96   // Debugging

    97   virtual void print() const;

    98   virtual void print_on(outputStream* st) const;

    99   virtual void print_short() const;

   100   virtual void print_short_on(outputStream* st) const;

   101   virtual void verify(bool allow_dirty) const;

   102 };

Mercurial > jdk8-mips64-public > hotspot / file revision

src/share/vm/gc_implementation/shared/mutableSpace.hpp@37f87013dfd8

src/share/vm/gc_implementation/shared/mutableSpace.hpp