g1BlockOffsetTable.inline.hpp revision 9056:dc9930a04ab0 
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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
33inline 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
41inline HeapWord*
42G1BlockOffsetTable::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
50u_char G1BlockOffsetSharedArray::offset_array(size_t index) const {
51  check_index(index, "index out of range");
52  return _offset_array[index];
53}
54
55void 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
60void 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
68void 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.
76inline size_t G1BlockOffsetSharedArray::index_for_raw(const void* p) const {
77  return pointer_delta((char*)p, _reserved.start(), sizeof(char)) >> LogN;
78}
79
80inline 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
91inline HeapWord*
92G1BlockOffsetSharedArray::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
102inline size_t
103G1BlockOffsetArray::block_size(const HeapWord* p) const {
104  return gsp()->block_size(p);
105}
106
107inline HeapWord*
108G1BlockOffsetArray::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
135inline HeapWord*
136G1BlockOffsetArray::
137forward_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
151inline HeapWord*
152G1BlockOffsetArray::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
168