Index: src/heap/mark-compact.cc |
diff --git a/src/heap/mark-compact.cc b/src/heap/mark-compact.cc |
index a64cf84fcd8143467edf1f5303df4009d0d06d98..ac595e6f5fb8d7b800dc22248d61549718e890d1 100644 |
--- a/src/heap/mark-compact.cc |
+++ b/src/heap/mark-compact.cc |
@@ -1818,15 +1818,6 @@ |
} |
}; |
-class MarkCompactCollector::EvacuateRecordOnlyVisitor final |
- : public MarkCompactCollector::HeapObjectVisitor { |
- public: |
- bool Visit(HeapObject* object) { |
- RecordMigratedSlotVisitor visitor; |
- object->IterateBodyFast(&visitor); |
- return true; |
- } |
-}; |
void MarkCompactCollector::DiscoverGreyObjectsInSpace(PagedSpace* space) { |
PageIterator it(space); |
@@ -3101,17 +3092,6 @@ |
DCHECK(chunk->IsEvacuationCandidate()); |
DCHECK_EQ(chunk->concurrent_sweeping_state().Value(), Page::kSweepingDone); |
success = EvacuateSinglePage<kClearMarkbits>(chunk, &old_space_visitor_); |
- if (!success) { |
- // Aborted compaction page. We can record slots here to have them |
- // processed in parallel later on. |
- EvacuateRecordOnlyVisitor record_visitor; |
- success = EvacuateSinglePage<kKeepMarking>(chunk, &record_visitor); |
- DCHECK(success); |
- USE(success); |
- // We need to return failure here to indicate that we want this page added |
- // to the sweeper. |
- return false; |
- } |
} |
return success; |
} |
@@ -3172,8 +3152,8 @@ |
return evacuator->EvacuatePage(chunk); |
} |
- static void FinalizePageSequentially(Heap* heap, MemoryChunk* chunk, |
- bool success, PerPageData data) { |
+ static void FinalizePageSequentially(Heap*, MemoryChunk* chunk, bool success, |
+ PerPageData data) { |
if (chunk->InNewSpace()) { |
DCHECK(success); |
} else { |
@@ -3185,12 +3165,17 @@ |
} else { |
// We have partially compacted the page, i.e., some objects may have |
// moved, others are still in place. |
+ // We need to: |
+ // - Leave the evacuation candidate flag for later processing of slots |
+ // buffer entries. |
+ // - Leave the slots buffer there for processing of entries added by |
+ // the write barrier. |
+ // - Rescan the page as slot recording in the migration buffer only |
+ // happens upon moving (which we potentially didn't do). |
+ // - Leave the page in the list of pages of a space since we could not |
+ // fully evacuate it. |
+ DCHECK(p->IsEvacuationCandidate()); |
p->SetFlag(Page::COMPACTION_WAS_ABORTED); |
- p->ClearEvacuationCandidate(); |
- // Slots have already been recorded so we just need to add it to the |
- // sweeper. |
- heap->mark_compact_collector()->sweeper().AddLatePage( |
- p->owner()->identity(), p); |
*data += 1; |
} |
} |
@@ -3434,6 +3419,42 @@ |
swept_list_[space->identity()].Add(page); |
} |
+void MarkCompactCollector::SweepAbortedPages() { |
+ // Second pass on aborted pages. |
+ for (Page* p : evacuation_candidates_) { |
+ if (p->IsFlagSet(Page::COMPACTION_WAS_ABORTED)) { |
+ p->ClearFlag(MemoryChunk::COMPACTION_WAS_ABORTED); |
+ p->concurrent_sweeping_state().SetValue(Page::kSweepingInProgress); |
+ PagedSpace* space = static_cast<PagedSpace*>(p->owner()); |
+ switch (space->identity()) { |
+ case OLD_SPACE: |
+ Sweeper::RawSweep<Sweeper::SWEEP_ONLY, Sweeper::SWEEP_ON_MAIN_THREAD, |
+ Sweeper::IGNORE_SKIP_LIST, |
+ Sweeper::IGNORE_FREE_SPACE>(space, p, nullptr); |
+ break; |
+ case CODE_SPACE: |
+ if (FLAG_zap_code_space) { |
+ Sweeper::RawSweep< |
+ Sweeper::SWEEP_ONLY, Sweeper::SWEEP_ON_MAIN_THREAD, |
+ Sweeper::REBUILD_SKIP_LIST, Sweeper::ZAP_FREE_SPACE>(space, p, |
+ nullptr); |
+ } else { |
+ Sweeper::RawSweep< |
+ Sweeper::SWEEP_ONLY, Sweeper::SWEEP_ON_MAIN_THREAD, |
+ Sweeper::REBUILD_SKIP_LIST, Sweeper::IGNORE_FREE_SPACE>( |
+ space, p, nullptr); |
+ } |
+ break; |
+ default: |
+ UNREACHABLE(); |
+ break; |
+ } |
+ sweeper().AddSweptPageSafe(space, p); |
+ } |
+ } |
+} |
+ |
+ |
void MarkCompactCollector::EvacuateNewSpaceAndCandidates() { |
TRACE_GC(heap()->tracer(), GCTracer::Scope::MC_EVACUATE); |
Heap::RelocationLock relocation_lock(heap()); |
@@ -3458,6 +3479,9 @@ |
{ |
TRACE_GC(heap()->tracer(), GCTracer::Scope::MC_EVACUATE_CLEAN_UP); |
+ // After updating all pointers, we can finally sweep the aborted pages, |
+ // effectively overriding any forward pointers. |
+ SweepAbortedPages(); |
// EvacuateNewSpaceAndCandidates iterates over new space objects and for |
// ArrayBuffers either re-registers them as live or promotes them. This is |
@@ -3615,15 +3639,18 @@ |
TRACE_GC(heap()->tracer(), |
GCTracer::Scope::MC_EVACUATE_UPDATE_POINTERS_BETWEEN_EVACUATED); |
for (Page* p : evacuation_candidates_) { |
- if (p->IsFlagSet(Page::COMPACTION_WAS_ABORTED)) { |
- p->ClearFlag(Page::COMPACTION_WAS_ABORTED); |
- } |
- if (!p->IsEvacuationCandidate()) continue; |
+ DCHECK(p->IsEvacuationCandidate()); |
// Important: skip list should be cleared only after roots were updated |
// because root iteration traverses the stack and might have to find |
// code objects from non-updated pc pointing into evacuation candidate. |
SkipList* list = p->skip_list(); |
if (list != NULL) list->Clear(); |
+ |
+ // First pass on aborted pages, fixing up all live objects. |
+ if (p->IsFlagSet(Page::COMPACTION_WAS_ABORTED)) { |
+ p->ClearEvacuationCandidate(); |
+ VisitLiveObjectsBody(p, &updating_visitor); |
+ } |
} |
} |