Mercurial > hg > truffle
annotate src/share/vm/gc_implementation/parallelScavenge/psPromotionLAB.cpp @ 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 2002-2006 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 #include "incls/_precompiled.incl" | |
| 26 #include "incls/_psPromotionLAB.cpp.incl" | |
| 27 | |
|
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ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
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0
diff
changeset
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28 size_t PSPromotionLAB::filler_header_size; |
| 0 | 29 |
| 30 // This is the shared initialization code. It sets up the basic pointers, | |
| 31 // and allows enough extra space for a filler object. We call a virtual | |
| 32 // method, "lab_is_valid()" to handle the different asserts the old/young | |
| 33 // labs require. | |
| 34 void PSPromotionLAB::initialize(MemRegion lab) { | |
| 35 assert(lab_is_valid(lab), "Sanity"); | |
| 36 | |
| 37 HeapWord* bottom = lab.start(); | |
| 38 HeapWord* end = lab.end(); | |
| 39 | |
| 40 set_bottom(bottom); | |
| 41 set_end(end); | |
| 42 set_top(bottom); | |
| 43 | |
|
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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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44 // Initialize after VM starts up because header_size depends on compressed |
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ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
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45 // oops. |
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6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
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changeset
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46 filler_header_size = align_object_size(typeArrayOopDesc::header_size(T_INT)); |
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ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
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47 |
| 0 | 48 // We can be initialized to a zero size! |
| 49 if (free() > 0) { | |
| 50 if (ZapUnusedHeapArea) { | |
| 51 debug_only(Copy::fill_to_words(top(), free()/HeapWordSize, badHeapWord)); | |
| 52 } | |
| 53 | |
| 54 // NOTE! We need to allow space for a filler object. | |
| 55 assert(lab.word_size() >= filler_header_size, "lab is too small"); | |
| 56 end = end - filler_header_size; | |
| 57 set_end(end); | |
| 58 | |
| 59 _state = needs_flush; | |
| 60 } else { | |
| 61 _state = zero_size; | |
| 62 } | |
| 63 | |
| 64 assert(this->top() <= this->end(), "pointers out of order"); | |
| 65 } | |
| 66 | |
| 67 // Fill all remaining lab space with an unreachable object. | |
| 68 // The goal is to leave a contiguous parseable span of objects. | |
| 69 void PSPromotionLAB::flush() { | |
| 70 assert(_state != flushed, "Attempt to flush PLAB twice"); | |
| 71 assert(top() <= end(), "pointers out of order"); | |
| 72 | |
| 73 // If we were initialized to a zero sized lab, there is | |
| 74 // nothing to flush | |
| 75 if (_state == zero_size) | |
| 76 return; | |
| 77 | |
| 78 // PLAB's never allocate the last aligned_header_size | |
| 79 // so they can always fill with an array. | |
| 80 HeapWord* tlab_end = end() + filler_header_size; | |
| 81 typeArrayOop filler_oop = (typeArrayOop) top(); | |
| 82 filler_oop->set_mark(markOopDesc::prototype()); | |
| 83 filler_oop->set_klass(Universe::intArrayKlassObj()); | |
| 84 const size_t array_length = | |
| 85 pointer_delta(tlab_end, top()) - typeArrayOopDesc::header_size(T_INT); | |
| 86 assert( (array_length * (HeapWordSize/sizeof(jint))) < (size_t)max_jint, "array too big in PSPromotionLAB"); | |
| 87 filler_oop->set_length((int)(array_length * (HeapWordSize/sizeof(jint)))); | |
| 88 | |
| 89 #ifdef ASSERT | |
| 90 // Note that we actually DO NOT want to use the aligned header size! | |
| 91 HeapWord* elt_words = ((HeapWord*)filler_oop) + typeArrayOopDesc::header_size(T_INT); | |
| 92 Copy::fill_to_words(elt_words, array_length, 0xDEAABABE); | |
| 93 #endif | |
| 94 | |
| 95 set_bottom(NULL); | |
| 96 set_end(NULL); | |
| 97 set_top(NULL); | |
| 98 | |
| 99 _state = flushed; | |
| 100 } | |
| 101 | |
| 102 bool PSPromotionLAB::unallocate_object(oop obj) { | |
| 103 assert(Universe::heap()->is_in(obj), "Object outside heap"); | |
| 104 | |
| 105 if (contains(obj)) { | |
| 106 HeapWord* object_end = (HeapWord*)obj + obj->size(); | |
| 107 assert(object_end <= top(), "Object crosses promotion LAB boundary"); | |
| 108 | |
| 109 if (object_end == top()) { | |
| 110 set_top((HeapWord*)obj); | |
| 111 return true; | |
| 112 } | |
| 113 } | |
| 114 | |
| 115 return false; | |
| 116 } | |
| 117 | |
| 118 // Fill all remaining lab space with an unreachable object. | |
| 119 // The goal is to leave a contiguous parseable span of objects. | |
| 120 void PSOldPromotionLAB::flush() { | |
| 121 assert(_state != flushed, "Attempt to flush PLAB twice"); | |
| 122 assert(top() <= end(), "pointers out of order"); | |
| 123 | |
| 124 if (_state == zero_size) | |
| 125 return; | |
| 126 | |
| 127 HeapWord* obj = top(); | |
| 128 | |
| 129 PSPromotionLAB::flush(); | |
| 130 | |
| 131 assert(_start_array != NULL, "Sanity"); | |
| 132 | |
| 133 _start_array->allocate_block(obj); | |
| 134 } | |
| 135 | |
| 136 #ifdef ASSERT | |
| 137 | |
| 138 bool PSYoungPromotionLAB::lab_is_valid(MemRegion lab) { | |
| 139 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); | |
| 140 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); | |
| 141 | |
| 142 MutableSpace* to_space = heap->young_gen()->to_space(); | |
| 143 MemRegion used = to_space->used_region(); | |
| 144 if (used.contains(lab)) { | |
| 145 return true; | |
| 146 } | |
| 147 | |
| 148 return false; | |
| 149 } | |
| 150 | |
| 151 bool PSOldPromotionLAB::lab_is_valid(MemRegion lab) { | |
| 152 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); | |
| 153 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); | |
| 154 assert(_start_array->covered_region().contains(lab), "Sanity"); | |
| 155 | |
| 156 PSOldGen* old_gen = heap->old_gen(); | |
| 157 MemRegion used = old_gen->object_space()->used_region(); | |
| 158 | |
| 159 if (used.contains(lab)) { | |
| 160 return true; | |
| 161 } | |
| 162 | |
| 163 return false; | |
| 164 } | |
| 165 | |
| 166 #endif /* ASSERT */ |