1 /*
2 * Copyright (c) 2001, 2015, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_VM_GC_G1_G1BLOCKOFFSETTABLE_INLINE_HPP
26 #define SHARE_VM_GC_G1_G1BLOCKOFFSETTABLE_INLINE_HPP
27
28 #include "gc/g1/g1BlockOffsetTable.hpp"
29 #include "gc/g1/heapRegion.hpp"
30 #include "gc/shared/memset_with_concurrent_readers.hpp"
31 #include "gc/shared/space.hpp"
32
33 inline HeapWord* G1BlockOffsetTable::block_start(const void* addr) {
34 if (addr >= _bottom && addr < _end) {
35 return block_start_unsafe(addr);
36 } else {
37 return NULL;
38 }
39 }
40
41 inline HeapWord*
42 G1BlockOffsetTable::block_start_const(const void* addr) const {
43 if (addr >= _bottom && addr < _end) {
44 return block_start_unsafe_const(addr);
45 } else {
46 return NULL;
47 }
48 }
49
50 u_char G1BlockOffsetSharedArray::offset_array(size_t index) const {
51 check_index(index, "index out of range");
52 return _offset_array[index];
53 }
54
55 void G1BlockOffsetSharedArray::set_offset_array(size_t index, u_char offset) {
56 check_index(index, "index out of range");
57 set_offset_array_raw(index, offset);
58 }
59
60 void G1BlockOffsetSharedArray::set_offset_array(size_t index, HeapWord* high, HeapWord* low) {
61 check_index(index, "index out of range");
62 assert(high >= low, "addresses out of order");
63 size_t offset = pointer_delta(high, low);
64 check_offset(offset, "offset too large");
65 set_offset_array(index, (u_char)offset);
66 }
67
68 void G1BlockOffsetSharedArray::set_offset_array(size_t left, size_t right, u_char offset) {
69 check_index(right, "right index out of range");
70 assert(left <= right, "indexes out of order");
71 size_t num_cards = right - left + 1;
72 memset_with_concurrent_readers(&_offset_array[left], offset, num_cards);
73 }
74
75 // Variant of index_for that does not check the index for validity.
76 inline size_t G1BlockOffsetSharedArray::index_for_raw(const void* p) const {
77 return pointer_delta((char*)p, _reserved.start(), sizeof(char)) >> LogN;
78 }
79
80 inline size_t G1BlockOffsetSharedArray::index_for(const void* p) const {
81 char* pc = (char*)p;
82 assert(pc >= (char*)_reserved.start() &&
83 pc < (char*)_reserved.end(),
84 "p (" PTR_FORMAT ") not in reserved [" PTR_FORMAT ", " PTR_FORMAT ")",
85 p2i(p), p2i(_reserved.start()), p2i(_reserved.end()));
86 size_t result = index_for_raw(p);
87 check_index(result, "bad index from address");
88 return result;
89 }
90
91 inline HeapWord*
92 G1BlockOffsetSharedArray::address_for_index(size_t index) const {
93 check_index(index, "index out of range");
94 HeapWord* result = address_for_index_raw(index);
95 assert(result >= _reserved.start() && result < _reserved.end(),
96 "bad address from index result " PTR_FORMAT
97 " _reserved.start() " PTR_FORMAT " _reserved.end() " PTR_FORMAT,
98 p2i(result), p2i(_reserved.start()), p2i(_reserved.end()));
99 return result;
100 }
101
102 inline size_t
103 G1BlockOffsetArray::block_size(const HeapWord* p) const {
104 return gsp()->block_size(p);
105 }
106
107 inline HeapWord*
108 G1BlockOffsetArray::block_at_or_preceding(const void* addr,
109 bool has_max_index,
110 size_t max_index) const {
111 assert(_array->offset_array(0) == 0, "objects can't cross covered areas");
112 size_t index = _array->index_for(addr);
113 // We must make sure that the offset table entry we use is valid. If
114 // "addr" is past the end, start at the last known one and go forward.
115 if (has_max_index) {
116 index = MIN2(index, max_index);
117 }
118 HeapWord* q = _array->address_for_index(index);
119
120 uint offset = _array->offset_array(index); // Extend u_char to uint.
121 while (offset >= N_words) {
122 // The excess of the offset from N_words indicates a power of Base
123 // to go back by.
124 size_t n_cards_back = BlockOffsetArray::entry_to_cards_back(offset);
125 q -= (N_words * n_cards_back);
126 assert(q >= gsp()->bottom(), "Went below bottom!");
127 index -= n_cards_back;
128 offset = _array->offset_array(index);
129 }
130 assert(offset < N_words, "offset too large");
131 q -= offset;
132 return q;
133 }
134
135 inline HeapWord*
136 G1BlockOffsetArray::
137 forward_to_block_containing_addr_const(HeapWord* q, HeapWord* n,
138 const void* addr) const {
139 if (addr >= gsp()->top()) return gsp()->top();
140 while (n <= addr) {
141 q = n;
142 oop obj = oop(q);
143 if (obj->klass_or_null() == NULL) return q;
144 n += block_size(q);
145 }
146 assert(q <= n, "wrong order for q and addr");
147 assert(addr < n, "wrong order for addr and n");
148 return q;
149 }
150
151 inline HeapWord*
152 G1BlockOffsetArray::forward_to_block_containing_addr(HeapWord* q,
153 const void* addr) {
154 if (oop(q)->klass_or_null() == NULL) return q;
155 HeapWord* n = q + block_size(q);
156 // In the normal case, where the query "addr" is a card boundary, and the
157 // offset table chunks are the same size as cards, the block starting at
158 // "q" will contain addr, so the test below will fail, and we'll fall
159 // through quickly.
160 if (n <= addr) {
161 q = forward_to_block_containing_addr_slow(q, n, addr);
162 }
163 assert(q <= addr, "wrong order for current and arg");
164 return q;
165 }
166
167 #endif // SHARE_VM_GC_G1_G1BLOCKOFFSETTABLE_INLINE_HPP