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_IMPLEMENTATION_G1_G1BLOCKOFFSETTABLE_INLINE_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1BLOCKOFFSETTABLE_INLINE_HPP
27
28 #include "gc_implementation/g1/g1BlockOffsetTable.hpp"
29 #include "gc_implementation/g1/heapRegion.inline.hpp"
30 #include "memory/space.hpp"
31
32 inline HeapWord* G1BlockOffsetTable::block_start(const void* addr) {
33 if (addr >= _bottom && addr < _end) {
34 return block_start_unsafe(addr);
35 } else {
36 return NULL;
37 }
38 }
39
40 inline HeapWord*
41 G1BlockOffsetTable::block_start_const(const void* addr) const {
42 if (addr >= _bottom && addr < _end) {
43 return block_start_unsafe_const(addr);
44 } else {
45 return NULL;
46 }
47 }
48
49 u_char G1BlockOffsetSharedArray::offset_array(size_t index) const {
50 check_index(index, "index out of range");
51 return _offset_array[index];
52 }
53
54 void G1BlockOffsetSharedArray::set_offset_array(size_t index, u_char offset) {
55 check_index(index, "index out of range");
56 set_offset_array_raw(index, offset);
57 }
58
59 void G1BlockOffsetSharedArray::set_offset_array(size_t index, HeapWord* high, HeapWord* low) {
60 check_index(index, "index out of range");
61 assert(high >= low, "addresses out of order");
62 size_t offset = pointer_delta(high, low);
63 check_offset(offset, "offset too large");
64 set_offset_array(index, (u_char)offset);
65 }
66
67 void G1BlockOffsetSharedArray::set_offset_array(size_t left, size_t right, u_char offset) {
68 check_index(right, "right index out of range");
69 assert(left <= right, "indexes out of order");
70 size_t num_cards = right - left + 1;
71 if (UseMemSetInBOT) {
72 memset(&_offset_array[left], offset, num_cards);
73 } else {
74 size_t i = left;
75 const size_t end = i + num_cards;
76 for (; i < end; i++) {
77 _offset_array[i] = offset;
78 }
79 }
80 }
81
82 // Variant of index_for that does not check the index for validity.
83 inline size_t G1BlockOffsetSharedArray::index_for_raw(const void* p) const {
84 return pointer_delta((char*)p, _reserved.start(), sizeof(char)) >> LogN;
85 }
86
87 inline size_t G1BlockOffsetSharedArray::index_for(const void* p) const {
88 char* pc = (char*)p;
89 assert(pc >= (char*)_reserved.start() &&
90 pc < (char*)_reserved.end(),
91 err_msg("p (" PTR_FORMAT ") not in reserved [" PTR_FORMAT ", " PTR_FORMAT ")",
92 p2i(p), p2i(_reserved.start()), p2i(_reserved.end())));
93 size_t result = index_for_raw(p);
94 check_index(result, "bad index from address");
95 return result;
96 }
97
98 inline HeapWord*
99 G1BlockOffsetSharedArray::address_for_index(size_t index) const {
100 check_index(index, "index out of range");
101 HeapWord* result = address_for_index_raw(index);
102 assert(result >= _reserved.start() && result < _reserved.end(),
103 err_msg("bad address from index result " PTR_FORMAT
104 " _reserved.start() " PTR_FORMAT " _reserved.end() "
105 PTR_FORMAT,
106 p2i(result), p2i(_reserved.start()), p2i(_reserved.end())));
107 return result;
108 }
109
110 inline size_t
111 G1BlockOffsetArray::block_size(const HeapWord* p) const {
112 return gsp()->block_size(p);
113 }
114
115 inline HeapWord*
116 G1BlockOffsetArray::block_at_or_preceding(const void* addr,
117 bool has_max_index,
118 size_t max_index) const {
119 assert(_array->offset_array(0) == 0, "objects can't cross covered areas");
120 size_t index = _array->index_for(addr);
121 // We must make sure that the offset table entry we use is valid. If
122 // "addr" is past the end, start at the last known one and go forward.
123 if (has_max_index) {
124 index = MIN2(index, max_index);
125 }
126 HeapWord* q = _array->address_for_index(index);
127
128 uint offset = _array->offset_array(index); // Extend u_char to uint.
129 while (offset >= N_words) {
130 // The excess of the offset from N_words indicates a power of Base
131 // to go back by.
132 size_t n_cards_back = BlockOffsetArray::entry_to_cards_back(offset);
133 q -= (N_words * n_cards_back);
134 assert(q >= gsp()->bottom(), "Went below bottom!");
135 index -= n_cards_back;
136 offset = _array->offset_array(index);
137 }
138 assert(offset < N_words, "offset too large");
139 q -= offset;
140 return q;
141 }
142
143 inline HeapWord*
144 G1BlockOffsetArray::
145 forward_to_block_containing_addr_const(HeapWord* q, HeapWord* n,
146 const void* addr) const {
147 if (addr >= gsp()->top()) return gsp()->top();
148 while (n <= addr) {
149 q = n;
150 oop obj = oop(q);
151 if (obj->klass_or_null() == NULL) return q;
152 n += block_size(q);
153 }
154 assert(q <= n, "wrong order for q and addr");
155 assert(addr < n, "wrong order for addr and n");
156 return q;
157 }
158
159 inline HeapWord*
160 G1BlockOffsetArray::forward_to_block_containing_addr(HeapWord* q,
161 const void* addr) {
162 if (oop(q)->klass_or_null() == NULL) return q;
163 HeapWord* n = q + block_size(q);
164 // In the normal case, where the query "addr" is a card boundary, and the
165 // offset table chunks are the same size as cards, the block starting at
166 // "q" will contain addr, so the test below will fail, and we'll fall
167 // through quickly.
168 if (n <= addr) {
169 q = forward_to_block_containing_addr_slow(q, n, addr);
170 }
171 assert(q <= addr, "wrong order for current and arg");
172 return q;
173 }
174
175 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1BLOCKOFFSETTABLE_INLINE_HPP