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/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* This code is free software; you can redistribute it and/or modify it
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*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#ifndef SHARE_GC_G1_G1BLOCKOFFSETTABLE_INLINE_HPP
#define SHARE_GC_G1_G1BLOCKOFFSETTABLE_INLINE_HPP
#include "gc/g1/g1BlockOffsetTable.hpp"
#include "gc/g1/heapRegion.hpp"
#include "gc/shared/memset_with_concurrent_readers.hpp"
#include "gc/shared/space.hpp"
#include "runtime/atomic.hpp"
inline HeapWord* G1BlockOffsetTablePart::block_start(const void* addr) {
if (addr >= _space->bottom() && addr < _space->end()) {
HeapWord* q = block_at_or_preceding(addr, true, _next_offset_index-1);
return forward_to_block_containing_addr(q, addr);
} else {
return NULL;
}
}
inline HeapWord* G1BlockOffsetTablePart::block_start_const(const void* addr) const {
if (addr >= _space->bottom() && addr < _space->end()) {
HeapWord* q = block_at_or_preceding(addr, true, _next_offset_index-1);
HeapWord* n = q + block_size(q);
return forward_to_block_containing_addr_const(q, n, addr);
} else {
return NULL;
}
}
u_char G1BlockOffsetTable::offset_array(size_t index) const {
check_index(index, "index out of range");
return Atomic::load(&_offset_array[index]);
}
void G1BlockOffsetTable::set_offset_array_raw(size_t index, u_char offset) {
Atomic::store(offset, &_offset_array[index]);
}
void G1BlockOffsetTable::set_offset_array(size_t index, u_char offset) {
check_index(index, "index out of range");
set_offset_array_raw(index, offset);
}
void G1BlockOffsetTable::set_offset_array(size_t index, HeapWord* high, HeapWord* low) {
check_index(index, "index out of range");
assert(high >= low, "addresses out of order");
size_t offset = pointer_delta(high, low);
check_offset(offset, "offset too large");
set_offset_array(index, (u_char)offset);
}
void G1BlockOffsetTable::set_offset_array(size_t left, size_t right, u_char offset) {
check_index(right, "right index out of range");
assert(left <= right, "indexes out of order");
size_t num_cards = right - left + 1;
memset_with_concurrent_readers
(const_cast<u_char*> (&_offset_array[left]), offset, num_cards);
}
// Variant of index_for that does not check the index for validity.
inline size_t G1BlockOffsetTable::index_for_raw(const void* p) const {
return pointer_delta((char*)p, _reserved.start(), sizeof(char)) >> BOTConstants::LogN;
}
inline size_t G1BlockOffsetTable::index_for(const void* p) const {
char* pc = (char*)p;
assert(pc >= (char*)_reserved.start() &&
pc < (char*)_reserved.end(),
"p (" PTR_FORMAT ") not in reserved [" PTR_FORMAT ", " PTR_FORMAT ")",
p2i(p), p2i(_reserved.start()), p2i(_reserved.end()));
size_t result = index_for_raw(p);
check_index(result, "bad index from address");
return result;
}
inline HeapWord* G1BlockOffsetTable::address_for_index(size_t index) const {
check_index(index, "index out of range");
HeapWord* result = address_for_index_raw(index);
assert(result >= _reserved.start() && result < _reserved.end(),
"bad address from index result " PTR_FORMAT
" _reserved.start() " PTR_FORMAT " _reserved.end() " PTR_FORMAT,
p2i(result), p2i(_reserved.start()), p2i(_reserved.end()));
return result;
}
inline size_t G1BlockOffsetTablePart::block_size(const HeapWord* p) const {
return _space->block_size(p);
}
inline HeapWord* G1BlockOffsetTablePart::block_at_or_preceding(const void* addr,
bool has_max_index,
size_t max_index) const {
assert(_object_can_span || _bot->offset_array(_bot->index_for(_space->bottom())) == 0,
"Object crossed region boundary, found offset %u instead of 0",
(uint) _bot->offset_array(_bot->index_for(_space->bottom())));
size_t index = _bot->index_for(addr);
// We must make sure that the offset table entry we use is valid. If
// "addr" is past the end, start at the last known one and go forward.
if (has_max_index) {
index = MIN2(index, max_index);
}
HeapWord* q = _bot->address_for_index(index);
uint offset = _bot->offset_array(index); // Extend u_char to uint.
while (offset >= BOTConstants::N_words) {
// The excess of the offset from N_words indicates a power of Base
// to go back by.
size_t n_cards_back = BOTConstants::entry_to_cards_back(offset);
q -= (BOTConstants::N_words * n_cards_back);
index -= n_cards_back;
offset = _bot->offset_array(index);
}
assert(offset < BOTConstants::N_words, "offset too large");
q -= offset;
return q;
}
inline HeapWord* G1BlockOffsetTablePart::forward_to_block_containing_addr_const(HeapWord* q, HeapWord* n,
const void* addr) const {
if (addr >= _space->top()) return _space->top();
while (n <= addr) {
q = n;
oop obj = oop(q);
if (obj->klass_or_null_acquire() == NULL) {
return q;
}
n += block_size(q);
}
assert(q <= n, "wrong order for q and addr");
assert(addr < n, "wrong order for addr and n");
return q;
}
inline HeapWord* G1BlockOffsetTablePart::forward_to_block_containing_addr(HeapWord* q,
const void* addr) {
if (oop(q)->klass_or_null_acquire() == NULL) {
return q;
}
HeapWord* n = q + block_size(q);
// In the normal case, where the query "addr" is a card boundary, and the
// offset table chunks are the same size as cards, the block starting at
// "q" will contain addr, so the test below will fail, and we'll fall
// through quickly.
if (n <= addr) {
q = forward_to_block_containing_addr_slow(q, n, addr);
}
assert(q <= addr, "wrong order for current and arg");
return q;
}
#endif // SHARE_GC_G1_G1BLOCKOFFSETTABLE_INLINE_HPP