Java example source code file (cardTableModRefBS.cpp)
The cardTableModRefBS.cpp Java example source code
/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
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*
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* 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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#include "precompiled.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/cardTableModRefBS.hpp"
#include "memory/cardTableRS.hpp"
#include "memory/sharedHeap.hpp"
#include "memory/space.hpp"
#include "memory/space.inline.hpp"
#include "memory/universe.hpp"
#include "runtime/java.hpp"
#include "runtime/mutexLocker.hpp"
#include "runtime/virtualspace.hpp"
#include "services/memTracker.hpp"
#include "utilities/macros.hpp"
#ifdef COMPILER1
#include "c1/c1_LIR.hpp"
#include "c1/c1_LIRGenerator.hpp"
#endif
// This kind of "BarrierSet" allows a "CollectedHeap" to detect and
// enumerate ref fields that have been modified (since the last
// enumeration.)
size_t CardTableModRefBS::cards_required(size_t covered_words)
{
// Add one for a guard card, used to detect errors.
const size_t words = align_size_up(covered_words, card_size_in_words);
return words / card_size_in_words + 1;
}
size_t CardTableModRefBS::compute_byte_map_size()
{
assert(_guard_index == cards_required(_whole_heap.word_size()) - 1,
"unitialized, check declaration order");
assert(_page_size != 0, "unitialized, check declaration order");
const size_t granularity = os::vm_allocation_granularity();
return align_size_up(_guard_index + 1, MAX2(_page_size, granularity));
}
CardTableModRefBS::CardTableModRefBS(MemRegion whole_heap,
int max_covered_regions):
ModRefBarrierSet(max_covered_regions),
_whole_heap(whole_heap),
_guard_index(cards_required(whole_heap.word_size()) - 1),
_last_valid_index(_guard_index - 1),
_page_size(os::vm_page_size()),
_byte_map_size(compute_byte_map_size())
{
_kind = BarrierSet::CardTableModRef;
HeapWord* low_bound = _whole_heap.start();
HeapWord* high_bound = _whole_heap.end();
assert((uintptr_t(low_bound) & (card_size - 1)) == 0, "heap must start at card boundary");
assert((uintptr_t(high_bound) & (card_size - 1)) == 0, "heap must end at card boundary");
assert(card_size <= 512, "card_size must be less than 512"); // why?
_covered = new MemRegion[max_covered_regions];
_committed = new MemRegion[max_covered_regions];
if (_covered == NULL || _committed == NULL) {
vm_exit_during_initialization("couldn't alloc card table covered region set.");
}
_cur_covered_regions = 0;
const size_t rs_align = _page_size == (size_t) os::vm_page_size() ? 0 :
MAX2(_page_size, (size_t) os::vm_allocation_granularity());
ReservedSpace heap_rs(_byte_map_size, rs_align, false);
MemTracker::record_virtual_memory_type((address)heap_rs.base(), mtGC);
os::trace_page_sizes("card table", _guard_index + 1, _guard_index + 1,
_page_size, heap_rs.base(), heap_rs.size());
if (!heap_rs.is_reserved()) {
vm_exit_during_initialization("Could not reserve enough space for the "
"card marking array");
}
// The assember store_check code will do an unsigned shift of the oop,
// then add it to byte_map_base, i.e.
//
// _byte_map = byte_map_base + (uintptr_t(low_bound) >> card_shift)
_byte_map = (jbyte*) heap_rs.base();
byte_map_base = _byte_map - (uintptr_t(low_bound) >> card_shift);
assert(byte_for(low_bound) == &_byte_map[0], "Checking start of map");
assert(byte_for(high_bound-1) <= &_byte_map[_last_valid_index], "Checking end of map");
jbyte* guard_card = &_byte_map[_guard_index];
uintptr_t guard_page = align_size_down((uintptr_t)guard_card, _page_size);
_guard_region = MemRegion((HeapWord*)guard_page, _page_size);
os::commit_memory_or_exit((char*)guard_page, _page_size, _page_size,
!ExecMem, "card table last card");
*guard_card = last_card;
_lowest_non_clean =
NEW_C_HEAP_ARRAY(CardArr, max_covered_regions, mtGC);
_lowest_non_clean_chunk_size =
NEW_C_HEAP_ARRAY(size_t, max_covered_regions, mtGC);
_lowest_non_clean_base_chunk_index =
NEW_C_HEAP_ARRAY(uintptr_t, max_covered_regions, mtGC);
_last_LNC_resizing_collection =
NEW_C_HEAP_ARRAY(int, max_covered_regions, mtGC);
if (_lowest_non_clean == NULL
|| _lowest_non_clean_chunk_size == NULL
|| _lowest_non_clean_base_chunk_index == NULL
|| _last_LNC_resizing_collection == NULL)
vm_exit_during_initialization("couldn't allocate an LNC array.");
for (int i = 0; i < max_covered_regions; i++) {
_lowest_non_clean[i] = NULL;
_lowest_non_clean_chunk_size[i] = 0;
_last_LNC_resizing_collection[i] = -1;
}
if (TraceCardTableModRefBS) {
gclog_or_tty->print_cr("CardTableModRefBS::CardTableModRefBS: ");
gclog_or_tty->print_cr(" "
" &_byte_map[0]: " INTPTR_FORMAT
" &_byte_map[_last_valid_index]: " INTPTR_FORMAT,
&_byte_map[0],
&_byte_map[_last_valid_index]);
gclog_or_tty->print_cr(" "
" byte_map_base: " INTPTR_FORMAT,
byte_map_base);
}
}
CardTableModRefBS::~CardTableModRefBS() {
if (_covered) {
delete[] _covered;
_covered = NULL;
}
if (_committed) {
delete[] _committed;
_committed = NULL;
}
if (_lowest_non_clean) {
FREE_C_HEAP_ARRAY(CardArr, _lowest_non_clean, mtGC);
_lowest_non_clean = NULL;
}
if (_lowest_non_clean_chunk_size) {
FREE_C_HEAP_ARRAY(size_t, _lowest_non_clean_chunk_size, mtGC);
_lowest_non_clean_chunk_size = NULL;
}
if (_lowest_non_clean_base_chunk_index) {
FREE_C_HEAP_ARRAY(uintptr_t, _lowest_non_clean_base_chunk_index, mtGC);
_lowest_non_clean_base_chunk_index = NULL;
}
if (_last_LNC_resizing_collection) {
FREE_C_HEAP_ARRAY(int, _last_LNC_resizing_collection, mtGC);
_last_LNC_resizing_collection = NULL;
}
}
int CardTableModRefBS::find_covering_region_by_base(HeapWord* base) {
int i;
for (i = 0; i < _cur_covered_regions; i++) {
if (_covered[i].start() == base) return i;
if (_covered[i].start() > base) break;
}
// If we didn't find it, create a new one.
assert(_cur_covered_regions < _max_covered_regions,
"too many covered regions");
// Move the ones above up, to maintain sorted order.
for (int j = _cur_covered_regions; j > i; j--) {
_covered[j] = _covered[j-1];
_committed[j] = _committed[j-1];
}
int res = i;
_cur_covered_regions++;
_covered[res].set_start(base);
_covered[res].set_word_size(0);
jbyte* ct_start = byte_for(base);
uintptr_t ct_start_aligned = align_size_down((uintptr_t)ct_start, _page_size);
_committed[res].set_start((HeapWord*)ct_start_aligned);
_committed[res].set_word_size(0);
return res;
}
int CardTableModRefBS::find_covering_region_containing(HeapWord* addr) {
for (int i = 0; i < _cur_covered_regions; i++) {
if (_covered[i].contains(addr)) {
return i;
}
}
assert(0, "address outside of heap?");
return -1;
}
HeapWord* CardTableModRefBS::largest_prev_committed_end(int ind) const {
HeapWord* max_end = NULL;
for (int j = 0; j < ind; j++) {
HeapWord* this_end = _committed[j].end();
if (this_end > max_end) max_end = this_end;
}
return max_end;
}
MemRegion CardTableModRefBS::committed_unique_to_self(int self,
MemRegion mr) const {
MemRegion result = mr;
for (int r = 0; r < _cur_covered_regions; r += 1) {
if (r != self) {
result = result.minus(_committed[r]);
}
}
// Never include the guard page.
result = result.minus(_guard_region);
return result;
}
void CardTableModRefBS::resize_covered_region(MemRegion new_region) {
// We don't change the start of a region, only the end.
assert(_whole_heap.contains(new_region),
"attempt to cover area not in reserved area");
debug_only(verify_guard();)
// collided is true if the expansion would push into another committed region
debug_only(bool collided = false;)
int const ind = find_covering_region_by_base(new_region.start());
MemRegion const old_region = _covered[ind];
assert(old_region.start() == new_region.start(), "just checking");
if (new_region.word_size() != old_region.word_size()) {
// Commit new or uncommit old pages, if necessary.
MemRegion cur_committed = _committed[ind];
// Extend the end of this _commited region
// to cover the end of any lower _committed regions.
// This forms overlapping regions, but never interior regions.
HeapWord* const max_prev_end = largest_prev_committed_end(ind);
if (max_prev_end > cur_committed.end()) {
cur_committed.set_end(max_prev_end);
}
// Align the end up to a page size (starts are already aligned).
jbyte* const new_end = byte_after(new_region.last());
HeapWord* new_end_aligned =
(HeapWord*) align_size_up((uintptr_t)new_end, _page_size);
assert(new_end_aligned >= (HeapWord*) new_end,
"align up, but less");
// Check the other regions (excludes "ind") to ensure that
// the new_end_aligned does not intrude onto the committed
// space of another region.
int ri = 0;
for (ri = 0; ri < _cur_covered_regions; ri++) {
if (ri != ind) {
if (_committed[ri].contains(new_end_aligned)) {
// The prior check included in the assert
// (new_end_aligned >= _committed[ri].start())
// is redundant with the "contains" test.
// Any region containing the new end
// should start at or beyond the region found (ind)
// for the new end (committed regions are not expected to
// be proper subsets of other committed regions).
assert(_committed[ri].start() >= _committed[ind].start(),
"New end of committed region is inconsistent");
new_end_aligned = _committed[ri].start();
// new_end_aligned can be equal to the start of its
// committed region (i.e., of "ind") if a second
// region following "ind" also start at the same location
// as "ind".
assert(new_end_aligned >= _committed[ind].start(),
"New end of committed region is before start");
debug_only(collided = true;)
// Should only collide with 1 region
break;
}
}
}
#ifdef ASSERT
for (++ri; ri < _cur_covered_regions; ri++) {
assert(!_committed[ri].contains(new_end_aligned),
"New end of committed region is in a second committed region");
}
#endif
// The guard page is always committed and should not be committed over.
// "guarded" is used for assertion checking below and recalls the fact
// that the would-be end of the new committed region would have
// penetrated the guard page.
HeapWord* new_end_for_commit = new_end_aligned;
DEBUG_ONLY(bool guarded = false;)
if (new_end_for_commit > _guard_region.start()) {
new_end_for_commit = _guard_region.start();
DEBUG_ONLY(guarded = true;)
}
if (new_end_for_commit > cur_committed.end()) {
// Must commit new pages.
MemRegion const new_committed =
MemRegion(cur_committed.end(), new_end_for_commit);
assert(!new_committed.is_empty(), "Region should not be empty here");
os::commit_memory_or_exit((char*)new_committed.start(),
new_committed.byte_size(), _page_size,
!ExecMem, "card table expansion");
// Use new_end_aligned (as opposed to new_end_for_commit) because
// the cur_committed region may include the guard region.
} else if (new_end_aligned < cur_committed.end()) {
// Must uncommit pages.
MemRegion const uncommit_region =
committed_unique_to_self(ind, MemRegion(new_end_aligned,
cur_committed.end()));
if (!uncommit_region.is_empty()) {
// It is not safe to uncommit cards if the boundary between
// the generations is moving. A shrink can uncommit cards
// owned by generation A but being used by generation B.
if (!UseAdaptiveGCBoundary) {
if (!os::uncommit_memory((char*)uncommit_region.start(),
uncommit_region.byte_size())) {
assert(false, "Card table contraction failed");
// The call failed so don't change the end of the
// committed region. This is better than taking the
// VM down.
new_end_aligned = _committed[ind].end();
}
} else {
new_end_aligned = _committed[ind].end();
}
}
}
// In any case, we can reset the end of the current committed entry.
_committed[ind].set_end(new_end_aligned);
#ifdef ASSERT
// Check that the last card in the new region is committed according
// to the tables.
bool covered = false;
for (int cr = 0; cr < _cur_covered_regions; cr++) {
if (_committed[cr].contains(new_end - 1)) {
covered = true;
break;
}
}
assert(covered, "Card for end of new region not committed");
#endif
// The default of 0 is not necessarily clean cards.
jbyte* entry;
if (old_region.last() < _whole_heap.start()) {
entry = byte_for(_whole_heap.start());
} else {
entry = byte_after(old_region.last());
}
assert(index_for(new_region.last()) < _guard_index,
"The guard card will be overwritten");
// This line commented out cleans the newly expanded region and
// not the aligned up expanded region.
// jbyte* const end = byte_after(new_region.last());
jbyte* const end = (jbyte*) new_end_for_commit;
assert((end >= byte_after(new_region.last())) || collided || guarded,
"Expect to be beyond new region unless impacting another region");
// do nothing if we resized downward.
#ifdef ASSERT
for (int ri = 0; ri < _cur_covered_regions; ri++) {
if (ri != ind) {
// The end of the new committed region should not
// be in any existing region unless it matches
// the start of the next region.
assert(!_committed[ri].contains(end) ||
(_committed[ri].start() == (HeapWord*) end),
"Overlapping committed regions");
}
}
#endif
if (entry < end) {
memset(entry, clean_card, pointer_delta(end, entry, sizeof(jbyte)));
}
}
// In any case, the covered size changes.
_covered[ind].set_word_size(new_region.word_size());
if (TraceCardTableModRefBS) {
gclog_or_tty->print_cr("CardTableModRefBS::resize_covered_region: ");
gclog_or_tty->print_cr(" "
" _covered[%d].start(): " INTPTR_FORMAT
" _covered[%d].last(): " INTPTR_FORMAT,
ind, _covered[ind].start(),
ind, _covered[ind].last());
gclog_or_tty->print_cr(" "
" _committed[%d].start(): " INTPTR_FORMAT
" _committed[%d].last(): " INTPTR_FORMAT,
ind, _committed[ind].start(),
ind, _committed[ind].last());
gclog_or_tty->print_cr(" "
" byte_for(start): " INTPTR_FORMAT
" byte_for(last): " INTPTR_FORMAT,
byte_for(_covered[ind].start()),
byte_for(_covered[ind].last()));
gclog_or_tty->print_cr(" "
" addr_for(start): " INTPTR_FORMAT
" addr_for(last): " INTPTR_FORMAT,
addr_for((jbyte*) _committed[ind].start()),
addr_for((jbyte*) _committed[ind].last()));
}
// Touch the last card of the covered region to show that it
// is committed (or SEGV).
debug_only((void) (*byte_for(_covered[ind].last()));)
debug_only(verify_guard();)
}
// Note that these versions are precise! The scanning code has to handle the
// fact that the write barrier may be either precise or imprecise.
void CardTableModRefBS::write_ref_field_work(void* field, oop newVal) {
inline_write_ref_field(field, newVal);
}
void CardTableModRefBS::non_clean_card_iterate_possibly_parallel(Space* sp,
MemRegion mr,
OopsInGenClosure* cl,
CardTableRS* ct) {
if (!mr.is_empty()) {
// Caller (process_strong_roots()) claims that all GC threads
// execute this call. With UseDynamicNumberOfGCThreads now all
// active GC threads execute this call. The number of active GC
// threads needs to be passed to par_non_clean_card_iterate_work()
// to get proper partitioning and termination.
//
// This is an example of where n_par_threads() is used instead
// of workers()->active_workers(). n_par_threads can be set to 0 to
// turn off parallelism. For example when this code is called as
// part of verification and SharedHeap::process_strong_roots() is being
// used, then n_par_threads() may have been set to 0. active_workers
// is not overloaded with the meaning that it is a switch to disable
// parallelism and so keeps the meaning of the number of
// active gc workers. If parallelism has not been shut off by
// setting n_par_threads to 0, then n_par_threads should be
// equal to active_workers. When a different mechanism for shutting
// off parallelism is used, then active_workers can be used in
// place of n_par_threads.
// This is an example of a path where n_par_threads is
// set to 0 to turn off parallism.
// [7] CardTableModRefBS::non_clean_card_iterate()
// [8] CardTableRS::younger_refs_in_space_iterate()
// [9] Generation::younger_refs_in_space_iterate()
// [10] OneContigSpaceCardGeneration::younger_refs_iterate()
// [11] CompactingPermGenGen::younger_refs_iterate()
// [12] CardTableRS::younger_refs_iterate()
// [13] SharedHeap::process_strong_roots()
// [14] G1CollectedHeap::verify()
// [15] Universe::verify()
// [16] G1CollectedHeap::do_collection_pause_at_safepoint()
//
int n_threads = SharedHeap::heap()->n_par_threads();
bool is_par = n_threads > 0;
if (is_par) {
#if INCLUDE_ALL_GCS
assert(SharedHeap::heap()->n_par_threads() ==
SharedHeap::heap()->workers()->active_workers(), "Mismatch");
non_clean_card_iterate_parallel_work(sp, mr, cl, ct, n_threads);
#else // INCLUDE_ALL_GCS
fatal("Parallel gc not supported here.");
#endif // INCLUDE_ALL_GCS
} else {
// We do not call the non_clean_card_iterate_serial() version below because
// we want to clear the cards (which non_clean_card_iterate_serial() does not
// do for us): clear_cl here does the work of finding contiguous dirty ranges
// of cards to process and clear.
DirtyCardToOopClosure* dcto_cl = sp->new_dcto_cl(cl, precision(),
cl->gen_boundary());
ClearNoncleanCardWrapper clear_cl(dcto_cl, ct);
clear_cl.do_MemRegion(mr);
}
}
}
// The iterator itself is not MT-aware, but
// MT-aware callers and closures can use this to
// accomplish dirty card iteration in parallel. The
// iterator itself does not clear the dirty cards, or
// change their values in any manner.
void CardTableModRefBS::non_clean_card_iterate_serial(MemRegion mr,
MemRegionClosure* cl) {
bool is_par = (SharedHeap::heap()->n_par_threads() > 0);
assert(!is_par ||
(SharedHeap::heap()->n_par_threads() ==
SharedHeap::heap()->workers()->active_workers()), "Mismatch");
for (int i = 0; i < _cur_covered_regions; i++) {
MemRegion mri = mr.intersection(_covered[i]);
if (mri.word_size() > 0) {
jbyte* cur_entry = byte_for(mri.last());
jbyte* limit = byte_for(mri.start());
while (cur_entry >= limit) {
jbyte* next_entry = cur_entry - 1;
if (*cur_entry != clean_card) {
size_t non_clean_cards = 1;
// Should the next card be included in this range of dirty cards.
while (next_entry >= limit && *next_entry != clean_card) {
non_clean_cards++;
cur_entry = next_entry;
next_entry--;
}
// The memory region may not be on a card boundary. So that
// objects beyond the end of the region are not processed, make
// cur_cards precise with regard to the end of the memory region.
MemRegion cur_cards(addr_for(cur_entry),
non_clean_cards * card_size_in_words);
MemRegion dirty_region = cur_cards.intersection(mri);
cl->do_MemRegion(dirty_region);
}
cur_entry = next_entry;
}
}
}
}
void CardTableModRefBS::dirty_MemRegion(MemRegion mr) {
assert((HeapWord*)align_size_down((uintptr_t)mr.start(), HeapWordSize) == mr.start(), "Unaligned start");
assert((HeapWord*)align_size_up ((uintptr_t)mr.end(), HeapWordSize) == mr.end(), "Unaligned end" );
jbyte* cur = byte_for(mr.start());
jbyte* last = byte_after(mr.last());
while (cur < last) {
*cur = dirty_card;
cur++;
}
}
void CardTableModRefBS::invalidate(MemRegion mr, bool whole_heap) {
assert((HeapWord*)align_size_down((uintptr_t)mr.start(), HeapWordSize) == mr.start(), "Unaligned start");
assert((HeapWord*)align_size_up ((uintptr_t)mr.end(), HeapWordSize) == mr.end(), "Unaligned end" );
for (int i = 0; i < _cur_covered_regions; i++) {
MemRegion mri = mr.intersection(_covered[i]);
if (!mri.is_empty()) dirty_MemRegion(mri);
}
}
void CardTableModRefBS::clear_MemRegion(MemRegion mr) {
// Be conservative: only clean cards entirely contained within the
// region.
jbyte* cur;
if (mr.start() == _whole_heap.start()) {
cur = byte_for(mr.start());
} else {
assert(mr.start() > _whole_heap.start(), "mr is not covered.");
cur = byte_after(mr.start() - 1);
}
jbyte* last = byte_after(mr.last());
memset(cur, clean_card, pointer_delta(last, cur, sizeof(jbyte)));
}
void CardTableModRefBS::clear(MemRegion mr) {
for (int i = 0; i < _cur_covered_regions; i++) {
MemRegion mri = mr.intersection(_covered[i]);
if (!mri.is_empty()) clear_MemRegion(mri);
}
}
void CardTableModRefBS::dirty(MemRegion mr) {
jbyte* first = byte_for(mr.start());
jbyte* last = byte_after(mr.last());
memset(first, dirty_card, last-first);
}
// Unlike several other card table methods, dirty_card_iterate()
// iterates over dirty cards ranges in increasing address order.
void CardTableModRefBS::dirty_card_iterate(MemRegion mr,
MemRegionClosure* cl) {
for (int i = 0; i < _cur_covered_regions; i++) {
MemRegion mri = mr.intersection(_covered[i]);
if (!mri.is_empty()) {
jbyte *cur_entry, *next_entry, *limit;
for (cur_entry = byte_for(mri.start()), limit = byte_for(mri.last());
cur_entry <= limit;
cur_entry = next_entry) {
next_entry = cur_entry + 1;
if (*cur_entry == dirty_card) {
size_t dirty_cards;
// Accumulate maximal dirty card range, starting at cur_entry
for (dirty_cards = 1;
next_entry <= limit && *next_entry == dirty_card;
dirty_cards++, next_entry++);
MemRegion cur_cards(addr_for(cur_entry),
dirty_cards*card_size_in_words);
cl->do_MemRegion(cur_cards);
}
}
}
}
}
MemRegion CardTableModRefBS::dirty_card_range_after_reset(MemRegion mr,
bool reset,
int reset_val) {
for (int i = 0; i < _cur_covered_regions; i++) {
MemRegion mri = mr.intersection(_covered[i]);
if (!mri.is_empty()) {
jbyte* cur_entry, *next_entry, *limit;
for (cur_entry = byte_for(mri.start()), limit = byte_for(mri.last());
cur_entry <= limit;
cur_entry = next_entry) {
next_entry = cur_entry + 1;
if (*cur_entry == dirty_card) {
size_t dirty_cards;
// Accumulate maximal dirty card range, starting at cur_entry
for (dirty_cards = 1;
next_entry <= limit && *next_entry == dirty_card;
dirty_cards++, next_entry++);
MemRegion cur_cards(addr_for(cur_entry),
dirty_cards*card_size_in_words);
if (reset) {
for (size_t i = 0; i < dirty_cards; i++) {
cur_entry[i] = reset_val;
}
}
return cur_cards;
}
}
}
}
return MemRegion(mr.end(), mr.end());
}
uintx CardTableModRefBS::ct_max_alignment_constraint() {
return card_size * os::vm_page_size();
}
void CardTableModRefBS::verify_guard() {
// For product build verification
guarantee(_byte_map[_guard_index] == last_card,
"card table guard has been modified");
}
void CardTableModRefBS::verify() {
verify_guard();
}
#ifndef PRODUCT
void CardTableModRefBS::verify_region(MemRegion mr,
jbyte val, bool val_equals) {
jbyte* start = byte_for(mr.start());
jbyte* end = byte_for(mr.last());
bool failures = false;
for (jbyte* curr = start; curr <= end; ++curr) {
jbyte curr_val = *curr;
bool failed = (val_equals) ? (curr_val != val) : (curr_val == val);
if (failed) {
if (!failures) {
tty->cr();
tty->print_cr("== CT verification failed: ["PTR_FORMAT","PTR_FORMAT"]", start, end);
tty->print_cr("== %sexpecting value: %d",
(val_equals) ? "" : "not ", val);
failures = true;
}
tty->print_cr("== card "PTR_FORMAT" ["PTR_FORMAT","PTR_FORMAT"], "
"val: %d", curr, addr_for(curr),
(HeapWord*) (((size_t) addr_for(curr)) + card_size),
(int) curr_val);
}
}
guarantee(!failures, "there should not have been any failures");
}
void CardTableModRefBS::verify_not_dirty_region(MemRegion mr) {
verify_region(mr, dirty_card, false /* val_equals */);
}
void CardTableModRefBS::verify_dirty_region(MemRegion mr) {
verify_region(mr, dirty_card, true /* val_equals */);
}
#endif
void CardTableModRefBS::print_on(outputStream* st) const {
st->print_cr("Card table byte_map: [" INTPTR_FORMAT "," INTPTR_FORMAT "] byte_map_base: " INTPTR_FORMAT,
_byte_map, _byte_map + _byte_map_size, byte_map_base);
}
bool CardTableModRefBSForCTRS::card_will_be_scanned(jbyte cv) {
return
CardTableModRefBS::card_will_be_scanned(cv) ||
_rs->is_prev_nonclean_card_val(cv);
};
bool CardTableModRefBSForCTRS::card_may_have_been_dirty(jbyte cv) {
return
cv != clean_card &&
(CardTableModRefBS::card_may_have_been_dirty(cv) ||
CardTableRS::youngergen_may_have_been_dirty(cv));
};
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