| /* |
| * Copyright 2000-2008 Sun Microsystems, Inc. All Rights Reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * 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). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| * CA 95054 USA or visit www.sun.com if you need additional information or |
| * have any questions. |
| * |
| */ |
| |
| // This kind of "BarrierSet" allows a "CollectedHeap" to detect and |
| // enumerate ref fields that have been modified (since the last |
| // enumeration.) |
| |
| # include "incls/_precompiled.incl" |
| # include "incls/_cardTableModRefBS.cpp.incl" |
| |
| 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."); |
| int i; |
| for (i = 0; i < max_covered_regions; i++) { |
| _covered[i].set_word_size(0); |
| _committed[i].set_word_size(0); |
| } |
| _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); |
| 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); |
| if (!os::commit_memory((char*)guard_page, _page_size, _page_size)) { |
| // Do better than this for Merlin |
| vm_exit_out_of_memory(_page_size, "card table last card"); |
| } |
| *guard_card = last_card; |
| |
| _lowest_non_clean = |
| NEW_C_HEAP_ARRAY(CardArr, max_covered_regions); |
| _lowest_non_clean_chunk_size = |
| NEW_C_HEAP_ARRAY(size_t, max_covered_regions); |
| _lowest_non_clean_base_chunk_index = |
| NEW_C_HEAP_ARRAY(uintptr_t, max_covered_regions); |
| _last_LNC_resizing_collection = |
| NEW_C_HEAP_ARRAY(int, max_covered_regions); |
| 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 (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); |
| } |
| } |
| |
| 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"); |
| int ri = 0; |
| for (ri = 0; ri < _cur_covered_regions; ri++) { |
| if (ri != ind) { |
| if (_committed[ri].contains(new_end_aligned)) { |
| assert((new_end_aligned >= _committed[ri].start()) && |
| (_committed[ri].start() > _committed[ind].start()), |
| "New end of committed region is inconsistent"); |
| new_end_aligned = _committed[ri].start(); |
| 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. |
| HeapWord* const new_end_for_commit = MIN2(new_end_aligned, |
| _guard_region.start()); |
| |
| 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"); |
| if (!os::commit_memory((char*)new_committed.start(), |
| new_committed.byte_size(), _page_size)) { |
| // Do better than this for Merlin |
| vm_exit_out_of_memory(new_committed.byte_size(), |
| "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()) { |
| 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(); |
| } |
| } |
| } |
| // In any case, we can reset the end of the current committed entry. |
| _committed[ind].set_end(new_end_aligned); |
| |
| // 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, |
| "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())); |
| } |
| 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); |
| } |
| |
| |
| bool CardTableModRefBS::claim_card(size_t card_index) { |
| jbyte val = _byte_map[card_index]; |
| if (val != claimed_card_val()) { |
| jbyte res = Atomic::cmpxchg((jbyte) claimed_card_val(), &_byte_map[card_index], val); |
| if (res == val) |
| return true; |
| else return false; |
| } |
| return false; |
| } |
| |
| void CardTableModRefBS::non_clean_card_iterate(Space* sp, |
| MemRegion mr, |
| DirtyCardToOopClosure* dcto_cl, |
| MemRegionClosure* cl, |
| bool clear) { |
| if (!mr.is_empty()) { |
| int n_threads = SharedHeap::heap()->n_par_threads(); |
| if (n_threads > 0) { |
| #ifndef SERIALGC |
| par_non_clean_card_iterate_work(sp, mr, dcto_cl, cl, clear, n_threads); |
| #else // SERIALGC |
| fatal("Parallel gc not supported here."); |
| #endif // SERIALGC |
| } else { |
| non_clean_card_iterate_work(mr, cl, clear); |
| } |
| } |
| } |
| |
| // NOTE: For this to work correctly, it is important that |
| // we look for non-clean cards below (so as to catch those |
| // marked precleaned), rather than look explicitly for dirty |
| // cards (and miss those marked precleaned). In that sense, |
| // the name precleaned is currently somewhat of a misnomer. |
| void CardTableModRefBS::non_clean_card_iterate_work(MemRegion mr, |
| MemRegionClosure* cl, |
| bool clear) { |
| // Figure out whether we have to worry about parallelism. |
| bool is_par = (SharedHeap::heap()->n_par_threads() > 1); |
| 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); |
| if (clear) { |
| for (size_t i = 0; i < non_clean_cards; i++) { |
| // Clean the dirty cards (but leave the other non-clean |
| // alone.) If parallel, do the cleaning atomically. |
| jbyte cur_entry_val = cur_entry[i]; |
| if (card_is_dirty_wrt_gen_iter(cur_entry_val)) { |
| if (is_par) { |
| jbyte res = Atomic::cmpxchg(clean_card, &cur_entry[i], cur_entry_val); |
| assert(res != clean_card, |
| "Dirty card mysteriously cleaned"); |
| } else { |
| cur_entry[i] = clean_card; |
| } |
| } |
| } |
| } |
| cl->do_MemRegion(dirty_region); |
| } |
| cur_entry = next_entry; |
| } |
| } |
| } |
| } |
| |
| void CardTableModRefBS::mod_oop_in_space_iterate(Space* sp, |
| OopClosure* cl, |
| bool clear, |
| bool before_save_marks) { |
| // Note that dcto_cl is resource-allocated, so there is no |
| // corresponding "delete". |
| DirtyCardToOopClosure* dcto_cl = sp->new_dcto_cl(cl, precision()); |
| MemRegion used_mr; |
| if (before_save_marks) { |
| used_mr = sp->used_region_at_save_marks(); |
| } else { |
| used_mr = sp->used_region(); |
| } |
| non_clean_card_iterate(sp, used_mr, dcto_cl, dcto_cl, clear); |
| } |
| |
| void CardTableModRefBS::dirty_MemRegion(MemRegion mr) { |
| 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) { |
| 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); |
| } |
| |
| // NOTES: |
| // (1) Unlike mod_oop_in_space_iterate() above, 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()); |
| } |
| |
| // Set all the dirty cards in the given region to "precleaned" state. |
| void CardTableModRefBS::preclean_dirty_cards(MemRegion mr) { |
| for (int i = 0; i < _cur_covered_regions; i++) { |
| MemRegion mri = mr.intersection(_covered[i]); |
| if (!mri.is_empty()) { |
| jbyte *cur_entry, *limit; |
| for (cur_entry = byte_for(mri.start()), limit = byte_for(mri.last()); |
| cur_entry <= limit; |
| cur_entry++) { |
| if (*cur_entry == dirty_card) { |
| *cur_entry = precleaned_card; |
| } |
| } |
| } |
| } |
| } |
| |
| 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 |
| class GuaranteeNotModClosure: public MemRegionClosure { |
| CardTableModRefBS* _ct; |
| public: |
| GuaranteeNotModClosure(CardTableModRefBS* ct) : _ct(ct) {} |
| void do_MemRegion(MemRegion mr) { |
| jbyte* entry = _ct->byte_for(mr.start()); |
| guarantee(*entry != CardTableModRefBS::clean_card, |
| "Dirty card in region that should be clean"); |
| } |
| }; |
| |
| void CardTableModRefBS::verify_clean_region(MemRegion mr) { |
| GuaranteeNotModClosure blk(this); |
| non_clean_card_iterate_work(mr, &blk, false); |
| } |
| #endif |
| |
| 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)); |
| }; |
