stefank@7333: /*
stefank@7333:  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
stefank@7333:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
stefank@7333:  *
stefank@7333:  * This code is free software; you can redistribute it and/or modify it
stefank@7333:  * under the terms of the GNU General Public License version 2 only, as
stefank@7333:  * published by the Free Software Foundation.
stefank@7333:  *
stefank@7333:  * This code is distributed in the hope that it will be useful, but WITHOUT
stefank@7333:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
stefank@7333:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
stefank@7333:  * version 2 for more details (a copy is included in the LICENSE file that
stefank@7333:  * accompanied this code).
stefank@7333:  *
stefank@7333:  * You should have received a copy of the GNU General Public License version
stefank@7333:  * 2 along with this work; if not, write to the Free Software Foundation,
stefank@7333:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
stefank@7333:  *
stefank@7333:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
stefank@7333:  * or visit www.oracle.com if you need additional information or have any
stefank@7333:  * questions.
stefank@7333:  *
stefank@7333:  */
stefank@7333: 
stefank@7333: #ifndef SHARE_VM_UTILITIES_CHUNKED_LIST_HPP
stefank@7333: #define SHARE_VM_UTILITIES_CHUNKED_LIST_HPP
stefank@7333: 
stefank@7333: #include "memory/allocation.hpp"
stefank@7333: #include "utilities/debug.hpp"
stefank@7333: 
stefank@7333: template <class T, MEMFLAGS F> class ChunkedList : public CHeapObj<F> {
stefank@7333:   template <class U> friend class TestChunkedList;
stefank@7333: 
stefank@7333:   static const size_t BufferSize = 64;
stefank@7333: 
stefank@7333:   T  _values[BufferSize];
stefank@7333:   T* _top;
stefank@7333: 
stefank@7333:   ChunkedList<T, F>* _next_used;
stefank@7333:   ChunkedList<T, F>* _next_free;
stefank@7333: 
stefank@7333:   T const * end() const {
stefank@7333:     return &_values[BufferSize];
stefank@7333:   }
stefank@7333: 
stefank@7333:  public:
stefank@7333:   ChunkedList<T, F>() : _top(_values), _next_used(NULL), _next_free(NULL) {}
stefank@7333: 
stefank@7333:   bool is_full() const {
stefank@7333:     return _top == end();
stefank@7333:   }
stefank@7333: 
stefank@7333:   void clear() {
stefank@7333:     _top = _values;
stefank@7333:     // Don't clear the next pointers since that would interfere
stefank@7333:     // with other threads trying to iterate through the lists.
stefank@7333:   }
stefank@7333: 
stefank@7333:   void push(T m) {
stefank@7333:     assert(!is_full(), "Buffer is full");
stefank@7333:     *_top = m;
stefank@7333:     _top++;
stefank@7333:   }
stefank@7333: 
stefank@7333:   void set_next_used(ChunkedList<T, F>* buffer) { _next_used = buffer; }
stefank@7333:   void set_next_free(ChunkedList<T, F>* buffer) { _next_free = buffer; }
stefank@7333: 
stefank@7333:   ChunkedList<T, F>* next_used() const          { return _next_used; }
stefank@7333:   ChunkedList<T, F>* next_free() const          { return _next_free; }
stefank@7333: 
stefank@7333:   size_t size() const {
stefank@7333:     return pointer_delta(_top, _values, sizeof(T));
stefank@7333:   }
stefank@7333: 
stefank@7333:   T at(size_t i) {
stefank@7333:     assert(i < size(), err_msg("IOOBE i: " SIZE_FORMAT " size(): " SIZE_FORMAT, i, size()));
stefank@7333:     return _values[i];
stefank@7333:   }
stefank@7333: };
stefank@7333: 
stefank@7333: #endif // SHARE_VM_UTILITIES_CHUNKED_LIST_HPP