block-allocator.hpp
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00001 /* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */ 00002 /* 00003 * Main authors: 00004 * Christian Schulte <schulte@gecode.org> 00005 * 00006 * Copyright: 00007 * Christian Schulte, 2004 00008 * 00009 * Last modified: 00010 * $Date: 2010-07-28 16:13:53 +0200 (Wed, 28 Jul 2010) $ by $Author: schulte $ 00011 * $Revision: 11292 $ 00012 * 00013 * This file is part of Gecode, the generic constraint 00014 * development environment: 00015 * http://www.gecode.org 00016 * 00017 * Permission is hereby granted, free of charge, to any person obtaining 00018 * a copy of this software and associated documentation files (the 00019 * "Software"), to deal in the Software without restriction, including 00020 * without limitation the rights to use, copy, modify, merge, publish, 00021 * distribute, sublicense, and/or sell copies of the Software, and to 00022 * permit persons to whom the Software is furnished to do so, subject to 00023 * the following conditions: 00024 * 00025 * The above copyright notice and this permission notice shall be 00026 * included in all copies or substantial portions of the Software. 00027 * 00028 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 00029 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 00030 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 00031 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 00032 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 00033 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 00034 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 00035 * 00036 */ 00037 00038 namespace Gecode { namespace Support { 00039 00048 template<class T, class A, int blocksize = 512> 00049 class BlockAllocator { 00050 private: 00052 A& a; 00054 class Block { 00055 public: 00056 T b[blocksize]; 00057 Block* next; 00058 }; 00060 Block* b; 00062 T* n; 00064 size_t _size; 00066 void allocate(void); 00067 public: 00069 BlockAllocator(A& a); 00071 ~BlockAllocator(void); 00073 A& allocator(void); 00075 T* operator ()(void); 00077 size_t size(void) const; 00078 }; 00079 00087 template<class T, class A, int blocksize = 512> 00088 class BlockClient { 00089 public: 00091 static void* operator new(size_t s, BlockAllocator<T,A,blocksize>& ba); 00093 static void operator delete(void*, BlockAllocator<T,A,blocksize>& ba); 00095 static void operator delete(void*); 00096 }; 00097 00098 00099 00100 template<class T, class A, int blocksize> 00101 forceinline 00102 BlockAllocator<T,A,blocksize>::BlockAllocator(A& a0) : a(a0) { 00103 b = static_cast<Block*>(a.ralloc(sizeof(Block))); 00104 b->next = NULL; 00105 n = &b->b[blocksize]; 00106 _size = sizeof(Block); 00107 } 00108 00109 template<class T, class A, int blocksize> 00110 forceinline 00111 BlockAllocator<T,A,blocksize>::~BlockAllocator(void) { 00112 while (b != NULL) { 00113 Block* f = b; b = b->next; 00114 a.rfree(f,sizeof(Block)); 00115 } 00116 } 00117 00118 template<class T, class A, int blocksize> 00119 forceinline A& 00120 BlockAllocator<T,A,blocksize>::allocator(void) { 00121 return a; 00122 } 00123 00124 template<class T, class A, int blocksize> 00125 forceinline T* 00126 BlockAllocator<T,A,blocksize>::operator ()(void) { 00127 T* t = --n; 00128 if (t == &b->b[0]) 00129 allocate(); 00130 return t; 00131 } 00132 00133 template<class T, class A, int blocksize> 00134 void 00135 BlockAllocator<T,A,blocksize>::allocate(void) { 00136 // Allocate another block 00137 Block* nb = static_cast<Block*>(a.ralloc(sizeof(Block))); 00138 nb->next = b; b = nb; 00139 n = &nb->b[blocksize]; 00140 _size += sizeof(Block); 00141 } 00142 00143 template<class T, class A, int blocksize> 00144 forceinline size_t 00145 BlockAllocator<T,A,blocksize>::size(void) const { 00146 return _size; 00147 } 00148 00149 00150 00151 template<class T, class A, int blocksize> 00152 forceinline void 00153 BlockClient<T,A,blocksize>::operator 00154 delete(void*,BlockAllocator<T,A,blocksize>&) { 00155 } 00156 template<class T, class A, int blocksize> 00157 forceinline void 00158 BlockClient<T,A,blocksize>::operator delete(void*) { 00159 } 00160 template<class T, class A, int blocksize> 00161 forceinline void* 00162 BlockClient<T,A,blocksize>::operator new(size_t, 00163 BlockAllocator<T,A,blocksize>& ba) { 00164 return ba(); 00165 } 00166 00167 }} 00168 00169 // STATISTICS: support-any