[176] | 1 | // -*- C++ -*- |
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| 2 | |
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| 3 | /* |
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| 4 | |
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| 5 | Heap Layers: An Extensible Memory Allocation Infrastructure |
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| 6 | |
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| 7 | Copyright (C) 2000-2003 by Emery Berger |
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| 8 | http://www.cs.umass.edu/~emery |
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| 9 | emery@cs.umass.edu |
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| 10 | |
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| 11 | This program is free software; you can redistribute it and/or modify |
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| 12 | it under the terms of the GNU General Public License as published by |
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| 13 | the Free Software Foundation; either version 2 of the License, or |
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| 14 | (at your option) any later version. |
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| 15 | |
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| 16 | This program is distributed in the hope that it will be useful, |
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| 17 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 18 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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| 19 | GNU General Public License for more details. |
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| 20 | |
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| 21 | You should have received a copy of the GNU General Public License |
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| 22 | along with this program; if not, write to the Free Software |
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| 23 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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| 24 | |
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| 25 | */ |
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| 26 | |
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| 27 | #ifndef _SEG_H_ |
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| 28 | #define _SEG_H_ |
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| 29 | |
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| 30 | #include <assert.h> |
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| 31 | |
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| 32 | #include "sassert.h" |
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| 33 | #include "reaplet.h" |
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| 34 | |
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| 35 | namespace HL { |
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| 36 | |
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| 37 | template <int ReapletSize, |
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| 38 | class SizeClassComputer, |
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| 39 | class TopHeap> |
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| 40 | class Seg : public TopHeap { |
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| 41 | public: |
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| 42 | |
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| 43 | enum { Alignment = sizeof(double) }; |
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| 44 | |
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| 45 | private: |
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| 46 | |
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| 47 | Seg (void) |
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| 48 | { |
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| 49 | sassert <(sizeof(Reaplet<ReapletSize>) == ReapletSize)> verifyReapletSize; |
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| 50 | } |
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| 51 | |
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| 52 | class SanityChecker { |
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| 53 | public: |
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| 54 | SanityChecker (Seg * s) |
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| 55 | : _s (s) |
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| 56 | { |
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| 57 | _s->sanityCheck(); |
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| 58 | } |
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| 59 | ~SanityChecker (void) { |
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| 60 | _s->sanityCheck(); |
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| 61 | } |
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| 62 | private: |
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| 63 | Seg * _s; |
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| 64 | }; |
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| 65 | |
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| 66 | |
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| 67 | #if 1 |
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| 68 | enum { TopAlignment = TopHeap::Alignment }; |
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| 69 | |
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| 70 | class VerifyAlignment : |
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| 71 | public sassert <TopAlignment % ReapletSize == 0> {}; |
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| 72 | #endif |
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| 73 | |
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| 74 | public: |
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| 75 | |
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| 76 | __forceinline Seg (void) { |
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| 77 | for (int i = 0; i < SizeClassComputer::NUM_BINS; i++) { |
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| 78 | available[i] = 0; |
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| 79 | full[i] = 0; |
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| 80 | } |
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| 81 | } |
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| 82 | |
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| 83 | ~Seg (void) { |
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| 84 | clear(); |
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| 85 | } |
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| 86 | |
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| 87 | __forceinline void * malloc (size_t sz) { |
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| 88 | SanityChecker c (this); |
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| 89 | assert (sz <= SizeClassComputer::BIG_OBJECT); |
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| 90 | const int SizeClass = SizeClassComputer::getSizeClass (sz); |
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| 91 | // Try to use one of our reaplets to satisfy the request. |
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| 92 | Reaplet<ReapletSize> * const xs = available[SizeClass]; |
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| 93 | if (xs) { |
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| 94 | // assert (!xs->isFull()); |
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| 95 | // We've got one. Now try to get some memory from it. |
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| 96 | void * const ptr = xs->malloc (SizeClassComputer::bins[SizeClass]); |
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| 97 | // printf ("allocated: %x\n", ptr); |
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| 98 | if (ptr) { |
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| 99 | // Success! We're out of here. |
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| 100 | return ptr; |
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| 101 | } else { |
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| 102 | // It's full. |
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| 103 | // printf ("Full - adios.\n"); |
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| 104 | removeFromAvailable (xs, SizeClass); |
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| 105 | } |
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| 106 | } |
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| 107 | // printf ("slow!\n"); |
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| 108 | // We have to go get more memory. |
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| 109 | return slowPathGetMoreMemory (sz); |
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| 110 | } |
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| 111 | |
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| 112 | |
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| 113 | __forceinline static size_t getSize (void * ptr) { |
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| 114 | return (enclosingReaplet (ptr))->getSize(); |
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| 115 | } |
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| 116 | |
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| 117 | __forceinline void free (void * ptr) { |
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| 118 | SanityChecker c (this); |
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| 119 | // printf ("seg free: r = %x\n", r); |
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| 120 | Reaplet<ReapletSize> * r = enclosingReaplet (ptr); |
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| 121 | // printf ("freeing %x to %x\n", ptr, r); |
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| 122 | // if (sz <= SizeClassComputer::BIG_OBJECT) { |
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| 123 | // It's a small object. Free it. |
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| 124 | bool wasFull = r->isFull(); // || !r->getAmountAllocated()) { |
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| 125 | r->free (ptr); |
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| 126 | if (wasFull) { |
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| 127 | moveFromFullToAvailable (r); |
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| 128 | } |
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| 129 | } |
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| 130 | |
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| 131 | void clear (void) { |
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| 132 | SanityChecker c (this); |
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| 133 | for (int i = 0; i < SizeClassComputer::NUM_BINS; i++) { |
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| 134 | clearOut (full[i]); |
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| 135 | clearOut (available[i]); |
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| 136 | } |
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| 137 | } |
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| 138 | |
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| 139 | private: |
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| 140 | |
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| 141 | __forceinline void * slowPathGetMoreMemory (const size_t sz) { |
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| 142 | // printf ("slowpathgetmorememory\n"); |
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| 143 | SanityChecker c (this); |
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| 144 | if (sz <= SizeClassComputer::BIG_OBJECT) { |
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| 145 | const int SizeClass = SizeClassComputer::getSizeClass (sz); |
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| 146 | do { |
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| 147 | // printf ("looking for more memory.\n"); |
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| 148 | Reaplet<ReapletSize> * xs = available[SizeClass]; |
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| 149 | // Look for an available reaplet. |
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| 150 | if (xs != 0) { |
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| 151 | assert (!xs->isFull()); |
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| 152 | // We've got one. Now try to get some memory from it. |
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| 153 | void * ptr = xs->malloc (SizeClassComputer::bins[SizeClass]); |
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| 154 | if (ptr) { |
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| 155 | // Success! |
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| 156 | // printf ("amt free = %d\n", enclosingReaplet(ptr)->getAmountFree()); |
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| 157 | // printf ("success: found more memory.\n"); |
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| 158 | return ptr; |
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| 159 | } else { |
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| 160 | // printf ("Adios!\n"); |
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| 161 | // This reaplet is out of memory. |
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| 162 | // Remove it from the available list. |
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| 163 | removeFromAvailable (xs, SizeClass); |
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| 164 | // Put it on the full list. |
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| 165 | putOnFullList (xs, SizeClass); |
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| 166 | } |
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| 167 | } else { |
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| 168 | // The current bin is empty - make another reaplet. |
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| 169 | int r = insertNewReaplet (SizeClass); |
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| 170 | if (!r) { |
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| 171 | return 0; |
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| 172 | } |
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| 173 | } |
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| 174 | } while (1); |
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| 175 | } else { |
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| 176 | return makeBigObject (sz); |
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| 177 | } |
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| 178 | } |
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| 179 | |
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| 180 | __forceinline void sanityCheck (void) { |
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| 181 | #if !defined(NDEBUG) |
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| 182 | // FIX ME |
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| 183 | //#error "whoa dude. slowing things down." |
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| 184 | Reaplet<ReapletSize> * q; |
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| 185 | for (int i = 0; i < SizeClassComputer::NUM_BINS; i++) { |
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| 186 | // Visit the available list. |
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| 187 | q = available[i]; |
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| 188 | if (q) { |
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| 189 | assert (q->getPrev() == 0); |
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| 190 | } |
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| 191 | while (q) { |
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| 192 | if (q->isFull()) { |
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| 193 | // printf ("allocated = %d\n", q->getAmountAllocated()); |
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| 194 | } |
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| 195 | assert (!q->isFull()); |
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| 196 | q = (Reaplet<ReapletSize> *) q->getNext(); |
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| 197 | } |
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| 198 | // Now visit the full list. |
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| 199 | q = full[i]; |
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| 200 | if (q) { |
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| 201 | assert (q->getPrev() == 0); |
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| 202 | } |
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| 203 | while (q) { |
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| 204 | assert (q->isFull()); |
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| 205 | q = (Reaplet<ReapletSize> *) q->getNext(); |
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| 206 | } |
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| 207 | } |
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| 208 | #endif |
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| 209 | } |
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| 210 | |
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| 211 | __forceinline |
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| 212 | void putOnFullList (Reaplet<ReapletSize> * xs, |
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| 213 | const int SizeClass) { |
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| 214 | // printf ("putOnFullList %d\n", SizeClass); |
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| 215 | SanityChecker c (this); |
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| 216 | // assert (!xs->isFull()); |
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| 217 | xs->setNext (full[SizeClass]); |
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| 218 | xs->setPrev (0); |
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| 219 | if (full[SizeClass]) { |
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| 220 | full[SizeClass]->setPrev (xs); |
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| 221 | } |
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| 222 | full[SizeClass] = xs; |
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| 223 | // xs->markFull(); |
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| 224 | } |
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| 225 | |
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| 226 | __forceinline void clearOut (Reaplet<ReapletSize> *& list) { |
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| 227 | SanityChecker c (this); |
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| 228 | Reaplet<ReapletSize> * q; |
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| 229 | q = list; |
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| 230 | while (q) { |
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| 231 | Reaplet<ReapletSize> * c = q; |
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| 232 | q = (Reaplet<ReapletSize> *) q->getNext(); |
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| 233 | TopHeap::free (c); |
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| 234 | } |
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| 235 | list = 0; |
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| 236 | } |
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| 237 | |
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| 238 | __forceinline void removeFromFullList (Reaplet<ReapletSize> * r, |
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| 239 | const size_t sz) { |
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| 240 | // printf ("removeFromFullList\n"); |
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| 241 | // prev <-> r <-> next => |
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| 242 | // prev <-> next |
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| 243 | SanityChecker c (this); |
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| 244 | // assert (r->isFull()); |
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| 245 | // Remove from full list. |
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| 246 | Reaplet<ReapletSize> * prev, * next; |
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| 247 | prev = (Reaplet<ReapletSize> *) r->getPrev(); |
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| 248 | next = (Reaplet<ReapletSize> *) r->getNext(); |
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| 249 | assert (prev != r); |
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| 250 | assert (next != r); |
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| 251 | if (prev) { |
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| 252 | prev->setNext (next); |
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| 253 | } |
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| 254 | if (next) { |
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| 255 | next->setPrev (prev); |
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| 256 | } |
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| 257 | const int SizeClass = SizeClassComputer::getSizeClass (sz); |
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| 258 | if (r == full[SizeClass]) { |
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| 259 | assert (prev == 0); |
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| 260 | full[SizeClass] = next; |
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| 261 | } |
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| 262 | assert (full[SizeClass] != r); |
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| 263 | // r->setPrev (0); |
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| 264 | // r->setNext (0); |
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| 265 | // r->markNotFull(); |
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| 266 | } |
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| 267 | |
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| 268 | __forceinline |
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| 269 | void moveFromFullToAvailable (Reaplet<ReapletSize> * r) { |
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| 270 | SanityChecker c (this); |
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| 271 | const size_t sz = r->getSize(); |
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| 272 | removeFromFullList (r, sz); |
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| 273 | // Put it on the available list. |
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| 274 | addToAvailableList (r, sz); |
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| 275 | assert (r->getPrev() == 0); |
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| 276 | } |
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| 277 | |
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| 278 | __forceinline |
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| 279 | void removeAndFreeReaplet (Reaplet<ReapletSize> * r) |
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| 280 | { |
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| 281 | SanityChecker c (this); |
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| 282 | assert (!r->isFull()); |
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| 283 | const size_t sz = r->getSize(); |
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| 284 | Reaplet<ReapletSize> * n |
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| 285 | = (Reaplet<ReapletSize> *) r->getNext(); |
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| 286 | Reaplet<ReapletSize> * p |
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| 287 | = (Reaplet<ReapletSize> *) r->getPrev(); |
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| 288 | if (n) { |
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| 289 | n->setPrev (p); |
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| 290 | } |
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| 291 | if (p) { |
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| 292 | p->setNext (n); |
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| 293 | } |
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| 294 | int sizeclass = SizeClassComputer::getSizeClass (sz); |
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| 295 | if (available[sizeclass] == r) { |
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| 296 | available[sizeclass] = n; |
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| 297 | } |
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| 298 | //r->setPrev ((Reaplet<ReapletSize> *) 1); |
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| 299 | //r->setNext ((Reaplet<ReapletSize> *) 1); |
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| 300 | //r->clear(); |
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| 301 | TopHeap::free (r); |
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| 302 | // printf ("reset %d\n", sz); |
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| 303 | } |
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| 304 | |
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| 305 | __forceinline |
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| 306 | int insertNewReaplet (int SizeClass) |
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| 307 | { |
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| 308 | // printf ("insertNewReaplet\n"); |
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| 309 | SanityChecker c (this); |
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| 310 | void * m = TopHeap::malloc (ReapletSize); |
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| 311 | // NOTE: TopHeap *must* add a reaplet prefix. |
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| 312 | // Ensure m is aligned properly. |
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| 313 | assert (((size_t) m & (ReapletSize - 1)) == 0); |
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| 314 | if (m == 0) { |
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| 315 | // printf ("NO MORE MEMORY!\n"); |
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| 316 | // No more memory. |
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| 317 | return 0; |
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| 318 | } |
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| 319 | // Make a new Reaplet for this size class. |
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| 320 | size_t ssz = SizeClassComputer::getClassSize (SizeClass); |
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| 321 | |
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| 322 | // printf ("new reaplet!: ssz = %d\n", ssz); |
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| 323 | available[SizeClass] = new (m) Reaplet<ReapletSize> (ssz); |
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| 324 | available[SizeClass]->clear(); |
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| 325 | return 1; |
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| 326 | } |
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| 327 | |
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| 328 | protected: |
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| 329 | |
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| 330 | __forceinline |
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| 331 | void addToAvailableList (Reaplet<ReapletSize> * r, |
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| 332 | size_t sz) |
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| 333 | { |
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| 334 | SanityChecker c (this); |
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| 335 | // assert (!r->isFull()); |
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| 336 | const int SizeClass = SizeClassComputer::getSizeClass (sz); |
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| 337 | Reaplet<ReapletSize> * head = available[SizeClass]; |
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| 338 | |
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| 339 | assert (head != r); |
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| 340 | |
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| 341 | // r |
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| 342 | // => r <-> head |
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| 343 | |
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| 344 | r->setPrev (0); |
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| 345 | r->setNext (head); |
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| 346 | if (head) { |
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| 347 | head->setPrev (r); |
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| 348 | } |
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| 349 | available[SizeClass] = r; |
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| 350 | } |
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| 351 | |
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| 352 | private: |
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| 353 | |
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| 354 | NO_INLINE void removeFromAvailable (Reaplet<ReapletSize> * xs, |
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| 355 | const int SizeClass) { |
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| 356 | // printf ("removefromavailable %d.\n", SizeClass); |
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| 357 | // The reaplet xs is out of memory. |
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| 358 | // Remove it from the linked list. |
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| 359 | // Note that it is the head of the linked list. |
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| 360 | // printf ("Removing REAPLET %x\n", xs); |
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| 361 | assert (xs->isFull()); |
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| 362 | assert (xs->getPrev() == 0); |
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| 363 | Reaplet<ReapletSize> * n |
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| 364 | = (Reaplet<ReapletSize> *) xs->getNext(); |
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| 365 | if (n) { |
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| 366 | // printf ("setprev.\n"); |
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| 367 | n->setPrev (0); |
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| 368 | assert (!n->isFull()); |
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| 369 | } |
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| 370 | available[SizeClass] = n; |
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| 371 | SanityChecker c (this); |
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| 372 | // xs->setPrev ((Reaplet<ReapletSize> *) 1); |
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| 373 | // xs->setNext ((Reaplet<ReapletSize> *) 1); |
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| 374 | assert (n == 0 || (n->getPrev() == 0)); |
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| 375 | } |
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| 376 | |
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| 377 | __forceinline static Reaplet<ReapletSize> * enclosingReaplet (void * ptr) { |
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| 378 | // Find the enclosing reaplet for this pointer. |
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| 379 | Reaplet<ReapletSize> * r |
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| 380 | = (Reaplet<ReapletSize> *) (((size_t) ptr) & ~(ReapletSize - 1)); |
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| 381 | return r; |
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| 382 | } |
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| 383 | |
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| 384 | #if 1 |
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| 385 | NO_INLINE |
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| 386 | void * makeBigObject (size_t sz) { |
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| 387 | // printf ("makeBigObject\n"); |
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| 388 | SanityChecker c (this); |
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| 389 | // printf ("make big object: %d\n", sz); |
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| 390 | // Allocate big objects from the top heap. These must be |
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| 391 | // ReapletSize aligned. |
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| 392 | assert (sz > SizeClassComputer::BIG_OBJECT); |
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| 393 | ReapletBase * m |
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| 394 | = (ReapletBase *) TopHeap::malloc (sz + sizeof(ReapletBase)); |
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| 395 | // printf ("m = %x, size = %d\n", m, ReapletSize); |
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| 396 | assert (((size_t) m & (ReapletSize - 1)) == 0); |
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| 397 | // Put a reaplet base object as a header in the beginning. We |
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| 398 | // need this for size information. |
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| 399 | if (m == 0) { |
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| 400 | return 0; |
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| 401 | } |
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| 402 | new (m) ReapletBase (sz, (char *) (m + 1)); |
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| 403 | return (void *) (m + 1); |
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| 404 | } |
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| 405 | #endif |
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| 406 | |
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| 407 | Reaplet<ReapletSize> * available[SizeClassComputer::NUM_BINS]; |
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| 408 | Reaplet<ReapletSize> * full[SizeClassComputer::NUM_BINS]; |
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| 409 | }; |
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| 410 | |
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| 411 | }; |
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| 412 | |
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| 413 | #endif |
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