g1BlockOffsetTable.inline.hpp revision 8413:92457dfb91bd 
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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.inline.hpp"
30#include "gc/shared/space.hpp"
31
32inline 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
40inline HeapWord*
41G1BlockOffsetTable::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
49u_char G1BlockOffsetSharedArray::offset_array(size_t index) const {
50  check_index(index, "index out of range");
51  return _offset_array[index];
52}
53
54void 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
59void 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
67void 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.
83inline size_t G1BlockOffsetSharedArray::index_for_raw(const void* p) const {
84  return pointer_delta((char*)p, _reserved.start(), sizeof(char)) >> LogN;
85}
86
87inline 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
98inline HeapWord*
99G1BlockOffsetSharedArray::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
110inline size_t
111G1BlockOffsetArray::block_size(const HeapWord* p) const {
112  return gsp()->block_size(p);
113}
114
115inline HeapWord*
116G1BlockOffsetArray::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
143inline HeapWord*
144G1BlockOffsetArray::
145forward_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
159inline HeapWord*
160G1BlockOffsetArray::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_G1_G1BLOCKOFFSETTABLE_INLINE_HPP
176