Mercurial > hg > truffle
diff src/share/vm/gc_implementation/g1/heapRegion.cpp @ 342:37f87013dfd8
6711316: Open source the Garbage-First garbage collector
Summary: First mercurial integration of the code for the Garbage-First garbage collector.
Reviewed-by: apetrusenko, iveresov, jmasa, sgoldman, tonyp, ysr
author | ysr |
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date | Thu, 05 Jun 2008 15:57:56 -0700 |
parents | |
children | 9bb2c10ac07b |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/gc_implementation/g1/heapRegion.cpp Thu Jun 05 15:57:56 2008 -0700 @@ -0,0 +1,874 @@ +/* + * Copyright 2001-2007 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. + * + */ + +#include "incls/_precompiled.incl" +#include "incls/_heapRegion.cpp.incl" + +HeapRegionDCTOC::HeapRegionDCTOC(G1CollectedHeap* g1, + HeapRegion* hr, OopClosure* cl, + CardTableModRefBS::PrecisionStyle precision, + FilterKind fk) : + ContiguousSpaceDCTOC(hr, cl, precision, NULL), + _hr(hr), _fk(fk), _g1(g1) +{} + +FilterOutOfRegionClosure::FilterOutOfRegionClosure(HeapRegion* r, + OopClosure* oc) : + _r_bottom(r->bottom()), _r_end(r->end()), + _oc(oc), _out_of_region(0) +{} + +class VerifyLiveClosure: public OopClosure { + G1CollectedHeap* _g1h; + CardTableModRefBS* _bs; + oop _containing_obj; + bool _failures; + int _n_failures; +public: + VerifyLiveClosure(G1CollectedHeap* g1h) : + _g1h(g1h), _bs(NULL), _containing_obj(NULL), + _failures(false), _n_failures(0) + { + BarrierSet* bs = _g1h->barrier_set(); + if (bs->is_a(BarrierSet::CardTableModRef)) + _bs = (CardTableModRefBS*)bs; + } + + void set_containing_obj(oop obj) { + _containing_obj = obj; + } + + bool failures() { return _failures; } + int n_failures() { return _n_failures; } + + virtual void do_oop(narrowOop* p) { + guarantee(false, "NYI"); + } + + void do_oop(oop* p) { + assert(_containing_obj != NULL, "Precondition"); + assert(!_g1h->is_obj_dead(_containing_obj), "Precondition"); + oop obj = *p; + if (obj != NULL) { + bool failed = false; + if (!_g1h->is_in_closed_subset(obj) || _g1h->is_obj_dead(obj)) { + if (!_failures) { + gclog_or_tty->print_cr(""); + gclog_or_tty->print_cr("----------"); + } + if (!_g1h->is_in_closed_subset(obj)) { + gclog_or_tty->print_cr("Field "PTR_FORMAT + " of live obj "PTR_FORMAT + " points to obj "PTR_FORMAT + " not in the heap.", + p, (void*) _containing_obj, (void*) obj); + } else { + gclog_or_tty->print_cr("Field "PTR_FORMAT + " of live obj "PTR_FORMAT + " points to dead obj "PTR_FORMAT".", + p, (void*) _containing_obj, (void*) obj); + } + gclog_or_tty->print_cr("Live obj:"); + _containing_obj->print_on(gclog_or_tty); + gclog_or_tty->print_cr("Bad referent:"); + obj->print_on(gclog_or_tty); + gclog_or_tty->print_cr("----------"); + _failures = true; + failed = true; + _n_failures++; + } + + if (!_g1h->full_collection()) { + HeapRegion* from = _g1h->heap_region_containing(p); + HeapRegion* to = _g1h->heap_region_containing(*p); + if (from != NULL && to != NULL && + from != to && + !to->popular() && + !to->isHumongous()) { + jbyte cv_obj = *_bs->byte_for_const(_containing_obj); + jbyte cv_field = *_bs->byte_for_const(p); + const jbyte dirty = CardTableModRefBS::dirty_card_val(); + + bool is_bad = !(from->is_young() + || to->rem_set()->contains_reference(p) + || !G1HRRSFlushLogBuffersOnVerify && // buffers were not flushed + (_containing_obj->is_objArray() ? + cv_field == dirty + : cv_obj == dirty || cv_field == dirty)); + if (is_bad) { + if (!_failures) { + gclog_or_tty->print_cr(""); + gclog_or_tty->print_cr("----------"); + } + gclog_or_tty->print_cr("Missing rem set entry:"); + gclog_or_tty->print_cr("Field "PTR_FORMAT + " of obj "PTR_FORMAT + ", in region %d ["PTR_FORMAT + ", "PTR_FORMAT"),", + p, (void*) _containing_obj, + from->hrs_index(), + from->bottom(), + from->end()); + _containing_obj->print_on(gclog_or_tty); + gclog_or_tty->print_cr("points to obj "PTR_FORMAT + " in region %d ["PTR_FORMAT + ", "PTR_FORMAT").", + (void*) obj, to->hrs_index(), + to->bottom(), to->end()); + obj->print_on(gclog_or_tty); + gclog_or_tty->print_cr("Obj head CTE = %d, field CTE = %d.", + cv_obj, cv_field); + gclog_or_tty->print_cr("----------"); + _failures = true; + if (!failed) _n_failures++; + } + } + } + } + } +}; + +template<class ClosureType> +HeapWord* walk_mem_region_loop(ClosureType* cl, G1CollectedHeap* g1h, + HeapRegion* hr, + HeapWord* cur, HeapWord* top) { + oop cur_oop = oop(cur); + int oop_size = cur_oop->size(); + HeapWord* next_obj = cur + oop_size; + while (next_obj < top) { + // Keep filtering the remembered set. + if (!g1h->is_obj_dead(cur_oop, hr)) { + // Bottom lies entirely below top, so we can call the + // non-memRegion version of oop_iterate below. +#ifndef PRODUCT + if (G1VerifyMarkingInEvac) { + VerifyLiveClosure vl_cl(g1h); + cur_oop->oop_iterate(&vl_cl); + } +#endif + cur_oop->oop_iterate(cl); + } + cur = next_obj; + cur_oop = oop(cur); + oop_size = cur_oop->size(); + next_obj = cur + oop_size; + } + return cur; +} + +void HeapRegionDCTOC::walk_mem_region_with_cl(MemRegion mr, + HeapWord* bottom, + HeapWord* top, + OopClosure* cl) { + G1CollectedHeap* g1h = _g1; + + int oop_size; + + OopClosure* cl2 = cl; + FilterIntoCSClosure intoCSFilt(this, g1h, cl); + FilterOutOfRegionClosure outOfRegionFilt(_hr, cl); + switch (_fk) { + case IntoCSFilterKind: cl2 = &intoCSFilt; break; + case OutOfRegionFilterKind: cl2 = &outOfRegionFilt; break; + } + + // Start filtering what we add to the remembered set. If the object is + // not considered dead, either because it is marked (in the mark bitmap) + // or it was allocated after marking finished, then we add it. Otherwise + // we can safely ignore the object. + if (!g1h->is_obj_dead(oop(bottom), _hr)) { +#ifndef PRODUCT + if (G1VerifyMarkingInEvac) { + VerifyLiveClosure vl_cl(g1h); + oop(bottom)->oop_iterate(&vl_cl, mr); + } +#endif + oop_size = oop(bottom)->oop_iterate(cl2, mr); + } else { + oop_size = oop(bottom)->size(); + } + + bottom += oop_size; + + if (bottom < top) { + // We replicate the loop below for several kinds of possible filters. + switch (_fk) { + case NoFilterKind: + bottom = walk_mem_region_loop(cl, g1h, _hr, bottom, top); + break; + case IntoCSFilterKind: { + FilterIntoCSClosure filt(this, g1h, cl); + bottom = walk_mem_region_loop(&filt, g1h, _hr, bottom, top); + break; + } + case OutOfRegionFilterKind: { + FilterOutOfRegionClosure filt(_hr, cl); + bottom = walk_mem_region_loop(&filt, g1h, _hr, bottom, top); + break; + } + default: + ShouldNotReachHere(); + } + + // Last object. Need to do dead-obj filtering here too. + if (!g1h->is_obj_dead(oop(bottom), _hr)) { +#ifndef PRODUCT + if (G1VerifyMarkingInEvac) { + VerifyLiveClosure vl_cl(g1h); + oop(bottom)->oop_iterate(&vl_cl, mr); + } +#endif + oop(bottom)->oop_iterate(cl2, mr); + } + } +} + +void HeapRegion::reset_after_compaction() { + G1OffsetTableContigSpace::reset_after_compaction(); + // After a compaction the mark bitmap is invalid, so we must + // treat all objects as being inside the unmarked area. + zero_marked_bytes(); + init_top_at_mark_start(); +} + + + +DirtyCardToOopClosure* +HeapRegion::new_dcto_closure(OopClosure* cl, + CardTableModRefBS::PrecisionStyle precision, + HeapRegionDCTOC::FilterKind fk) { + return new HeapRegionDCTOC(G1CollectedHeap::heap(), + this, cl, precision, fk); +} + +void HeapRegion::hr_clear(bool par, bool clear_space) { + _humongous = false; + _humongous_start = false; + _humongous_start_region = NULL; + _in_collection_set = false; + _is_gc_alloc_region = false; + + // Age stuff (if parallel, this will be done separately, since it needs + // to be sequential). + G1CollectedHeap* g1h = G1CollectedHeap::heap(); + + set_young_index_in_cset(-1); + uninstall_surv_rate_group(); + set_young_type(NotYoung); + + // In case it had been the start of a humongous sequence, reset its end. + set_end(_orig_end); + + if (!par) { + // If this is parallel, this will be done later. + HeapRegionRemSet* hrrs = rem_set(); + if (hrrs != NULL) hrrs->clear(); + _claimed = 0; + } + zero_marked_bytes(); + set_sort_index(-1); + if ((uintptr_t)bottom() >= (uintptr_t)g1h->popular_object_boundary()) + set_popular(false); + + _offsets.resize(HeapRegion::GrainWords); + init_top_at_mark_start(); + if (clear_space) clear(); +} + +// <PREDICTION> +void HeapRegion::calc_gc_efficiency() { + G1CollectedHeap* g1h = G1CollectedHeap::heap(); + _gc_efficiency = (double) garbage_bytes() / + g1h->predict_region_elapsed_time_ms(this, false); +} +// </PREDICTION> + +void HeapRegion::set_startsHumongous() { + _humongous_start = true; _humongous = true; + _humongous_start_region = this; + assert(end() == _orig_end, "Should be normal before alloc."); +} + +bool HeapRegion::claimHeapRegion(jint claimValue) { + jint current = _claimed; + if (current != claimValue) { + jint res = Atomic::cmpxchg(claimValue, &_claimed, current); + if (res == current) { + return true; + } + } + return false; +} + +HeapWord* HeapRegion::next_block_start_careful(HeapWord* addr) { + HeapWord* low = addr; + HeapWord* high = end(); + while (low < high) { + size_t diff = pointer_delta(high, low); + // Must add one below to bias toward the high amount. Otherwise, if + // "high" were at the desired value, and "low" were one less, we + // would not converge on "high". This is not symmetric, because + // we set "high" to a block start, which might be the right one, + // which we don't do for "low". + HeapWord* middle = low + (diff+1)/2; + if (middle == high) return high; + HeapWord* mid_bs = block_start_careful(middle); + if (mid_bs < addr) { + low = middle; + } else { + high = mid_bs; + } + } + assert(low == high && low >= addr, "Didn't work."); + return low; +} + +void HeapRegion::set_next_on_unclean_list(HeapRegion* r) { + assert(r == NULL || r->is_on_unclean_list(), "Malformed unclean list."); + _next_in_special_set = r; +} + +void HeapRegion::set_on_unclean_list(bool b) { + _is_on_unclean_list = b; +} + +void HeapRegion::initialize(MemRegion mr, bool clear_space) { + G1OffsetTableContigSpace::initialize(mr, false); + hr_clear(false/*par*/, clear_space); +} +#ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away +#pragma warning( disable:4355 ) // 'this' : used in base member initializer list +#endif // _MSC_VER + + +HeapRegion:: +HeapRegion(G1BlockOffsetSharedArray* sharedOffsetArray, + MemRegion mr, bool is_zeroed) + : G1OffsetTableContigSpace(sharedOffsetArray, mr, is_zeroed), + _next_fk(HeapRegionDCTOC::NoFilterKind), + _hrs_index(-1), + _humongous(false), _humongous_start(false), _humongous_start_region(NULL), + _in_collection_set(false), _is_gc_alloc_region(false), + _is_on_free_list(false), _is_on_unclean_list(false), + _next_in_special_set(NULL), _orig_end(NULL), + _claimed(0), _evacuation_failed(false), + _prev_marked_bytes(0), _next_marked_bytes(0), _sort_index(-1), + _popularity(NotPopular), + _young_type(NotYoung), _next_young_region(NULL), + _young_index_in_cset(-1), _surv_rate_group(NULL), _age_index(-1), + _rem_set(NULL), _zfs(NotZeroFilled) +{ + _orig_end = mr.end(); + // Note that initialize() will set the start of the unmarked area of the + // region. + this->initialize(mr, !is_zeroed); + + _rem_set = new HeapRegionRemSet(sharedOffsetArray, this); + + assert(HeapRegionRemSet::num_par_rem_sets() > 0, "Invariant."); + // In case the region is allocated during a pause, note the top. + // We haven't done any counting on a brand new region. + _top_at_conc_mark_count = bottom(); +} + +class NextCompactionHeapRegionClosure: public HeapRegionClosure { + const HeapRegion* _target; + bool _target_seen; + HeapRegion* _last; + CompactibleSpace* _res; +public: + NextCompactionHeapRegionClosure(const HeapRegion* target) : + _target(target), _target_seen(false), _res(NULL) {} + bool doHeapRegion(HeapRegion* cur) { + if (_target_seen) { + if (!cur->isHumongous()) { + _res = cur; + return true; + } + } else if (cur == _target) { + _target_seen = true; + } + return false; + } + CompactibleSpace* result() { return _res; } +}; + +CompactibleSpace* HeapRegion::next_compaction_space() const { + G1CollectedHeap* g1h = G1CollectedHeap::heap(); + // cast away const-ness + HeapRegion* r = (HeapRegion*) this; + NextCompactionHeapRegionClosure blk(r); + g1h->heap_region_iterate_from(r, &blk); + return blk.result(); +} + +void HeapRegion::set_continuesHumongous(HeapRegion* start) { + // The order is important here. + start->add_continuingHumongousRegion(this); + _humongous = true; _humongous_start = false; + _humongous_start_region = start; +} + +void HeapRegion::add_continuingHumongousRegion(HeapRegion* cont) { + // Must join the blocks of the current H region seq with the block of the + // added region. + offsets()->join_blocks(bottom(), cont->bottom()); + arrayOop obj = (arrayOop)(bottom()); + obj->set_length((int) (obj->length() + cont->capacity()/jintSize)); + set_end(cont->end()); + set_top(cont->end()); +} + +void HeapRegion::save_marks() { + set_saved_mark(); +} + +void HeapRegion::oops_in_mr_iterate(MemRegion mr, OopClosure* cl) { + HeapWord* p = mr.start(); + HeapWord* e = mr.end(); + oop obj; + while (p < e) { + obj = oop(p); + p += obj->oop_iterate(cl); + } + assert(p == e, "bad memregion: doesn't end on obj boundary"); +} + +#define HeapRegion_OOP_SINCE_SAVE_MARKS_DEFN(OopClosureType, nv_suffix) \ +void HeapRegion::oop_since_save_marks_iterate##nv_suffix(OopClosureType* cl) { \ + ContiguousSpace::oop_since_save_marks_iterate##nv_suffix(cl); \ +} +SPECIALIZED_SINCE_SAVE_MARKS_CLOSURES(HeapRegion_OOP_SINCE_SAVE_MARKS_DEFN) + + +void HeapRegion::oop_before_save_marks_iterate(OopClosure* cl) { + oops_in_mr_iterate(MemRegion(bottom(), saved_mark_word()), cl); +} + +#ifdef DEBUG +HeapWord* HeapRegion::allocate(size_t size) { + jint state = zero_fill_state(); + assert(!G1CollectedHeap::heap()->allocs_are_zero_filled() || + zero_fill_is_allocated(), + "When ZF is on, only alloc in ZF'd regions"); + return G1OffsetTableContigSpace::allocate(size); +} +#endif + +void HeapRegion::set_zero_fill_state_work(ZeroFillState zfs) { + assert(top() == bottom() || zfs == Allocated, + "Region must be empty, or we must be setting it to allocated."); + assert(ZF_mon->owned_by_self() || + Universe::heap()->is_gc_active(), + "Must hold the lock or be a full GC to modify."); + _zfs = zfs; +} + +void HeapRegion::set_zero_fill_complete() { + set_zero_fill_state_work(ZeroFilled); + if (ZF_mon->owned_by_self()) { + ZF_mon->notify_all(); + } +} + + +void HeapRegion::ensure_zero_filled() { + MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag); + ensure_zero_filled_locked(); +} + +void HeapRegion::ensure_zero_filled_locked() { + assert(ZF_mon->owned_by_self(), "Precondition"); + bool should_ignore_zf = SafepointSynchronize::is_at_safepoint(); + assert(should_ignore_zf || Heap_lock->is_locked(), + "Either we're in a GC or we're allocating a region."); + switch (zero_fill_state()) { + case HeapRegion::NotZeroFilled: + set_zero_fill_in_progress(Thread::current()); + { + ZF_mon->unlock(); + Copy::fill_to_words(bottom(), capacity()/HeapWordSize); + ZF_mon->lock_without_safepoint_check(); + } + // A trap. + guarantee(zero_fill_state() == HeapRegion::ZeroFilling + && zero_filler() == Thread::current(), + "AHA! Tell Dave D if you see this..."); + set_zero_fill_complete(); + // gclog_or_tty->print_cr("Did sync ZF."); + ConcurrentZFThread::note_sync_zfs(); + break; + case HeapRegion::ZeroFilling: + if (should_ignore_zf) { + // We can "break" the lock and take over the work. + Copy::fill_to_words(bottom(), capacity()/HeapWordSize); + set_zero_fill_complete(); + ConcurrentZFThread::note_sync_zfs(); + break; + } else { + ConcurrentZFThread::wait_for_ZF_completed(this); + } + case HeapRegion::ZeroFilled: + // Nothing to do. + break; + case HeapRegion::Allocated: + guarantee(false, "Should not call on allocated regions."); + } + assert(zero_fill_state() == HeapRegion::ZeroFilled, "Post"); +} + +HeapWord* +HeapRegion::object_iterate_mem_careful(MemRegion mr, + ObjectClosure* cl) { + G1CollectedHeap* g1h = G1CollectedHeap::heap(); + // We used to use "block_start_careful" here. But we're actually happy + // to update the BOT while we do this... + HeapWord* cur = block_start(mr.start()); + mr = mr.intersection(used_region()); + if (mr.is_empty()) return NULL; + // Otherwise, find the obj that extends onto mr.start(). + + assert(cur <= mr.start() + && (oop(cur)->klass() == NULL || + cur + oop(cur)->size() > mr.start()), + "postcondition of block_start"); + oop obj; + while (cur < mr.end()) { + obj = oop(cur); + if (obj->klass() == NULL) { + // Ran into an unparseable point. + return cur; + } else if (!g1h->is_obj_dead(obj)) { + cl->do_object(obj); + } + if (cl->abort()) return cur; + // The check above must occur before the operation below, since an + // abort might invalidate the "size" operation. + cur += obj->size(); + } + return NULL; +} + +HeapWord* +HeapRegion:: +oops_on_card_seq_iterate_careful(MemRegion mr, + FilterOutOfRegionClosure* cl) { + G1CollectedHeap* g1h = G1CollectedHeap::heap(); + + // If we're within a stop-world GC, then we might look at a card in a + // GC alloc region that extends onto a GC LAB, which may not be + // parseable. Stop such at the "saved_mark" of the region. + if (G1CollectedHeap::heap()->is_gc_active()) { + mr = mr.intersection(used_region_at_save_marks()); + } else { + mr = mr.intersection(used_region()); + } + if (mr.is_empty()) return NULL; + // Otherwise, find the obj that extends onto mr.start(). + + // We used to use "block_start_careful" here. But we're actually happy + // to update the BOT while we do this... + HeapWord* cur = block_start(mr.start()); + assert(cur <= mr.start(), "Postcondition"); + + while (cur <= mr.start()) { + if (oop(cur)->klass() == NULL) { + // Ran into an unparseable point. + return cur; + } + // Otherwise... + int sz = oop(cur)->size(); + if (cur + sz > mr.start()) break; + // Otherwise, go on. + cur = cur + sz; + } + oop obj; + obj = oop(cur); + // If we finish this loop... + assert(cur <= mr.start() + && obj->klass() != NULL + && cur + obj->size() > mr.start(), + "Loop postcondition"); + if (!g1h->is_obj_dead(obj)) { + obj->oop_iterate(cl, mr); + } + + HeapWord* next; + while (cur < mr.end()) { + obj = oop(cur); + if (obj->klass() == NULL) { + // Ran into an unparseable point. + return cur; + }; + // Otherwise: + next = (cur + obj->size()); + if (!g1h->is_obj_dead(obj)) { + if (next < mr.end()) { + obj->oop_iterate(cl); + } else { + // this obj spans the boundary. If it's an array, stop at the + // boundary. + if (obj->is_objArray()) { + obj->oop_iterate(cl, mr); + } else { + obj->oop_iterate(cl); + } + } + } + cur = next; + } + return NULL; +} + +void HeapRegion::print() const { print_on(gclog_or_tty); } +void HeapRegion::print_on(outputStream* st) const { + if (isHumongous()) { + if (startsHumongous()) + st->print(" HS"); + else + st->print(" HC"); + } else { + st->print(" "); + } + if (in_collection_set()) + st->print(" CS"); + else if (is_gc_alloc_region()) + st->print(" A "); + else + st->print(" "); + if (is_young()) + st->print(is_scan_only() ? " SO" : (is_survivor() ? " SU" : " Y ")); + else + st->print(" "); + if (is_empty()) + st->print(" F"); + else + st->print(" "); + st->print(" %d", _gc_time_stamp); + G1OffsetTableContigSpace::print_on(st); +} + +#define OBJ_SAMPLE_INTERVAL 0 +#define BLOCK_SAMPLE_INTERVAL 100 + +// This really ought to be commoned up into OffsetTableContigSpace somehow. +// We would need a mechanism to make that code skip dead objects. + +void HeapRegion::verify(bool allow_dirty) const { + G1CollectedHeap* g1 = G1CollectedHeap::heap(); + HeapWord* p = bottom(); + HeapWord* prev_p = NULL; + int objs = 0; + int blocks = 0; + VerifyLiveClosure vl_cl(g1); + while (p < top()) { + size_t size = oop(p)->size(); + if (blocks == BLOCK_SAMPLE_INTERVAL) { + guarantee(p == block_start_const(p + (size/2)), + "check offset computation"); + blocks = 0; + } else { + blocks++; + } + if (objs == OBJ_SAMPLE_INTERVAL) { + oop obj = oop(p); + if (!g1->is_obj_dead(obj, this)) { + obj->verify(); + vl_cl.set_containing_obj(obj); + obj->oop_iterate(&vl_cl); + if (G1MaxVerifyFailures >= 0 + && vl_cl.n_failures() >= G1MaxVerifyFailures) break; + } + objs = 0; + } else { + objs++; + } + prev_p = p; + p += size; + } + HeapWord* rend = end(); + HeapWord* rtop = top(); + if (rtop < rend) { + guarantee(block_start_const(rtop + (rend - rtop) / 2) == rtop, + "check offset computation"); + } + if (vl_cl.failures()) { + gclog_or_tty->print_cr("Heap:"); + G1CollectedHeap::heap()->print(); + gclog_or_tty->print_cr(""); + } + if (G1VerifyConcMark && + G1VerifyConcMarkPrintReachable && + vl_cl.failures()) { + g1->concurrent_mark()->print_prev_bitmap_reachable(); + } + guarantee(!vl_cl.failures(), "should not have had any failures"); + guarantee(p == top(), "end of last object must match end of space"); +} + +// G1OffsetTableContigSpace code; copied from space.cpp. Hope this can go +// away eventually. + +void G1OffsetTableContigSpace::initialize(MemRegion mr, bool clear_space) { + // false ==> we'll do the clearing if there's clearing to be done. + ContiguousSpace::initialize(mr, false); + _offsets.zero_bottom_entry(); + _offsets.initialize_threshold(); + if (clear_space) clear(); +} + +void G1OffsetTableContigSpace::clear() { + ContiguousSpace::clear(); + _offsets.zero_bottom_entry(); + _offsets.initialize_threshold(); +} + +void G1OffsetTableContigSpace::set_bottom(HeapWord* new_bottom) { + Space::set_bottom(new_bottom); + _offsets.set_bottom(new_bottom); +} + +void G1OffsetTableContigSpace::set_end(HeapWord* new_end) { + Space::set_end(new_end); + _offsets.resize(new_end - bottom()); +} + +void G1OffsetTableContigSpace::print() const { + print_short(); + gclog_or_tty->print_cr(" [" INTPTR_FORMAT ", " INTPTR_FORMAT ", " + INTPTR_FORMAT ", " INTPTR_FORMAT ")", + bottom(), top(), _offsets.threshold(), end()); +} + +HeapWord* G1OffsetTableContigSpace::initialize_threshold() { + return _offsets.initialize_threshold(); +} + +HeapWord* G1OffsetTableContigSpace::cross_threshold(HeapWord* start, + HeapWord* end) { + _offsets.alloc_block(start, end); + return _offsets.threshold(); +} + +HeapWord* G1OffsetTableContigSpace::saved_mark_word() const { + G1CollectedHeap* g1h = G1CollectedHeap::heap(); + assert( _gc_time_stamp <= g1h->get_gc_time_stamp(), "invariant" ); + if (_gc_time_stamp < g1h->get_gc_time_stamp()) + return top(); + else + return ContiguousSpace::saved_mark_word(); +} + +void G1OffsetTableContigSpace::set_saved_mark() { + G1CollectedHeap* g1h = G1CollectedHeap::heap(); + unsigned curr_gc_time_stamp = g1h->get_gc_time_stamp(); + + if (_gc_time_stamp < curr_gc_time_stamp) { + // The order of these is important, as another thread might be + // about to start scanning this region. If it does so after + // set_saved_mark and before _gc_time_stamp = ..., then the latter + // will be false, and it will pick up top() as the high water mark + // of region. If it does so after _gc_time_stamp = ..., then it + // will pick up the right saved_mark_word() as the high water mark + // of the region. Either way, the behaviour will be correct. + ContiguousSpace::set_saved_mark(); + OrderAccess::release_store_ptr((volatile intptr_t*) &_gc_time_stamp, + (intptr_t) curr_gc_time_stamp); + } +} + +G1OffsetTableContigSpace:: +G1OffsetTableContigSpace(G1BlockOffsetSharedArray* sharedOffsetArray, + MemRegion mr, bool is_zeroed) : + _offsets(sharedOffsetArray, mr), + _par_alloc_lock(Mutex::leaf, "OffsetTableContigSpace par alloc lock", true), + _gc_time_stamp(0) +{ + _offsets.set_space(this); + initialize(mr, !is_zeroed); +} + +size_t RegionList::length() { + size_t len = 0; + HeapRegion* cur = hd(); + DEBUG_ONLY(HeapRegion* last = NULL); + while (cur != NULL) { + len++; + DEBUG_ONLY(last = cur); + cur = get_next(cur); + } + assert(last == tl(), "Invariant"); + return len; +} + +void RegionList::insert_before_head(HeapRegion* r) { + assert(well_formed(), "Inv"); + set_next(r, hd()); + _hd = r; + _sz++; + if (tl() == NULL) _tl = r; + assert(well_formed(), "Inv"); +} + +void RegionList::prepend_list(RegionList* new_list) { + assert(well_formed(), "Precondition"); + assert(new_list->well_formed(), "Precondition"); + HeapRegion* new_tl = new_list->tl(); + if (new_tl != NULL) { + set_next(new_tl, hd()); + _hd = new_list->hd(); + _sz += new_list->sz(); + if (tl() == NULL) _tl = new_list->tl(); + } else { + assert(new_list->hd() == NULL && new_list->sz() == 0, "Inv"); + } + assert(well_formed(), "Inv"); +} + +void RegionList::delete_after(HeapRegion* r) { + assert(well_formed(), "Precondition"); + HeapRegion* next = get_next(r); + assert(r != NULL, "Precondition"); + HeapRegion* next_tl = get_next(next); + set_next(r, next_tl); + dec_sz(); + if (next == tl()) { + assert(next_tl == NULL, "Inv"); + _tl = r; + } + assert(well_formed(), "Inv"); +} + +HeapRegion* RegionList::pop() { + assert(well_formed(), "Inv"); + HeapRegion* res = hd(); + if (res != NULL) { + _hd = get_next(res); + _sz--; + set_next(res, NULL); + if (sz() == 0) _tl = NULL; + } + assert(well_formed(), "Inv"); + return res; +}