Mercurial > hg > truffle
annotate src/share/vm/gc_implementation/parallelScavenge/prefetchQueue.hpp @ 113:ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
Summary: Compressed oops in instances, arrays, and headers. Code contributors are coleenp, phh, never, swamyv
Reviewed-by: jmasa, kamg, acorn, tbell, kvn, rasbold
| author | coleenp |
|---|---|
| date | Sun, 13 Apr 2008 17:43:42 -0400 |
| parents | a61af66fc99e |
| children | d1605aabd0a1 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 * Copyright 2002-2003 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 */ | |
| 24 | |
| 25 // | |
| 26 // PrefetchQueue is a FIFO queue of variable length (currently 8). | |
| 27 // | |
| 28 // We need to examine the performance penalty of variable lengths. | |
| 29 // We may also want to split this into cpu dependant bits. | |
| 30 // | |
| 31 | |
| 32 const int PREFETCH_QUEUE_SIZE = 8; | |
| 33 | |
| 34 class PrefetchQueue : public CHeapObj { | |
| 35 private: | |
|
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ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
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36 void* _prefetch_queue[PREFETCH_QUEUE_SIZE]; |
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ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
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changeset
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37 uint _prefetch_index; |
| 0 | 38 |
| 39 public: | |
| 40 int length() { return PREFETCH_QUEUE_SIZE; } | |
| 41 | |
| 42 inline void clear() { | |
| 43 for(int i=0; i<PREFETCH_QUEUE_SIZE; i++) { | |
| 44 _prefetch_queue[i] = NULL; | |
| 45 } | |
| 46 _prefetch_index = 0; | |
| 47 } | |
| 48 | |
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6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
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49 template <class T> inline void* push_and_pop(T* p) { |
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6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
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50 oop o = oopDesc::load_decode_heap_oop_not_null(p); |
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ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
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diff
changeset
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51 Prefetch::write(o->mark_addr(), 0); |
| 0 | 52 // This prefetch is intended to make sure the size field of array |
| 53 // oops is in cache. It assumes the the object layout is | |
| 54 // mark -> klass -> size, and that mark and klass are heapword | |
| 55 // sized. If this should change, this prefetch will need updating! | |
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113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
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56 Prefetch::write(o->mark_addr() + (HeapWordSize*2), 0); |
| 0 | 57 _prefetch_queue[_prefetch_index++] = p; |
| 58 _prefetch_index &= (PREFETCH_QUEUE_SIZE-1); | |
| 59 return _prefetch_queue[_prefetch_index]; | |
| 60 } | |
| 61 | |
| 62 // Stores a NULL pointer in the pop'd location. | |
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113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
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63 inline void* pop() { |
| 0 | 64 _prefetch_queue[_prefetch_index++] = NULL; |
| 65 _prefetch_index &= (PREFETCH_QUEUE_SIZE-1); | |
| 66 return _prefetch_queue[_prefetch_index]; | |
| 67 } | |
| 68 }; |