[heap] Refactor marking verification

Use MarkingState to abstract over the different sets of markbits.

BUG=chromium:651354

Change-Id: I1635eb0d441be2aeed19f0ed91999f0f0f1bbffc
Reviewed-on: https://chromium-review.googlesource.com/458398Reviewed-by: Hannes Payer <hpayer@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44024}

src/heap/mark-compact.cc

@@ -65,58 +65,51 @@ MarkCompactCollector::MarkCompactCollector(Heap* heap)
 }
 
 #ifdef VERIFY_HEAP
-class VerifyMarkingVisitor : public ObjectVisitor {
+class MarkingVerifier : public ObjectVisitor {
  public:
-  void VisitPointers(Object** start, Object** end) override {
-    for (Object** current = start; current < end; current++) {
-      if ((*current)->IsHeapObject()) {
-        HeapObject* object = HeapObject::cast(*current);
-        CHECK(ObjectMarking::IsBlackOrGrey(object));
-      }
-    }
-  }
+  virtual void Run() = 0;
 
-  void VisitEmbeddedPointer(RelocInfo* rinfo) override {
-    DCHECK(rinfo->rmode() == RelocInfo::EMBEDDED_OBJECT);
-    if (!rinfo->host()->IsWeakObject(rinfo->target_object())) {
-      Object* p = rinfo->target_object();
-      VisitPointer(&p);
-    }
-  }
+ protected:
+  explicit MarkingVerifier(Heap* heap) : heap_(heap) {}
 
-  void VisitCell(RelocInfo* rinfo) override {
-    Code* code = rinfo->host();
-    DCHECK(rinfo->rmode() == RelocInfo::CELL);
-    if (!code->IsWeakObject(rinfo->target_cell())) {
-      ObjectVisitor::VisitCell(rinfo);
-    }
-  }
+  virtual MarkingState marking_state(MemoryChunk* chunk) = 0;
+
+  void VerifyRoots(VisitMode mode);
+  void VerifyMarkingOnPage(const Page& page, const MarkingState& state,
+                           Address start, Address end);
+  void VerifyMarking(NewSpace* new_space);
+  void VerifyMarking(PagedSpace* paged_space);
+
+  Heap* heap_;
 };
 
+void MarkingVerifier::VerifyRoots(VisitMode mode) {
+  heap_->IterateStrongRoots(this, mode);
+}
 
-static void VerifyMarking(Heap* heap, Address bottom, Address top) {
-  VerifyMarkingVisitor visitor;
+void MarkingVerifier::VerifyMarkingOnPage(const Page& page,
+                                          const MarkingState& state,
+                                          Address start, Address end) {
   HeapObject* object;
-  Address next_object_must_be_here_or_later = bottom;
-  for (Address current = bottom; current < top;) {
+  Address next_object_must_be_here_or_later = start;
+  for (Address current = start; current < end;) {
     object = HeapObject::FromAddress(current);
     // One word fillers at the end of a black area can be grey.
-    if (ObjectMarking::IsBlackOrGrey(object) &&
-        object->map() != heap->one_pointer_filler_map()) {
-      CHECK(ObjectMarking::IsBlack(object));
+    if (ObjectMarking::IsBlackOrGrey(object, state) &&
+        object->map() != heap_->one_pointer_filler_map()) {
+      CHECK(ObjectMarking::IsBlack(object, state));
       CHECK(current >= next_object_must_be_here_or_later);
-      object->Iterate(&visitor);
+      object->Iterate(this);
       next_object_must_be_here_or_later = current + object->Size();
       // The object is either part of a black area of black allocation or a
       // regular black object
-      Page* page = Page::FromAddress(current);
       CHECK(
-          page->markbits()->AllBitsSetInRange(
-              page->AddressToMarkbitIndex(current),
-              page->AddressToMarkbitIndex(next_object_must_be_here_or_later)) ||
-          page->markbits()->AllBitsClearInRange(
-              page->AddressToMarkbitIndex(current + kPointerSize * 2),
-              page->AddressToMarkbitIndex(next_object_must_be_here_or_later)));
+          state.bitmap->AllBitsSetInRange(
+              page.AddressToMarkbitIndex(current),
+              page.AddressToMarkbitIndex(next_object_must_be_here_or_later)) ||
+          state.bitmap->AllBitsClearInRange(
+              page.AddressToMarkbitIndex(current + kPointerSize * 2),
+              page.AddressToMarkbitIndex(next_object_must_be_here_or_later)));
       current = next_object_must_be_here_or_later;
     } else {
       current += kPointerSize;
@@ -124,7 +117,7 @@ static void VerifyMarking(Heap* heap, Address bottom, Address top) {
   }
 }
 
-static void VerifyMarking(NewSpace* space) {
+void MarkingVerifier::VerifyMarking(NewSpace* space) {
   Address end = space->top();
   // The bottom position is at the start of its page. Allows us to use
   // page->area_start() as start of range on all pages.
@@ -135,36 +128,97 @@ static void VerifyMarking(NewSpace* space) {
     Page* page = *(it++);
     Address limit = it != range.end() ? page->area_end() : end;
     CHECK(limit == end || !page->Contains(end));
-    VerifyMarking(space->heap(), page->area_start(), limit);
+    VerifyMarkingOnPage(*page, marking_state(page), page->area_start(), limit);
   }
 }
 
-
-static void VerifyMarking(PagedSpace* space) {
+void MarkingVerifier::VerifyMarking(PagedSpace* space) {
   for (Page* p : *space) {
-    VerifyMarking(space->heap(), p->area_start(), p->area_end());
+    VerifyMarkingOnPage(*p, marking_state(p), p->area_start(), p->area_end());
   }
 }
 
+class FullMarkingVerifier : public MarkingVerifier {
+ public:
+  explicit FullMarkingVerifier(Heap* heap) : MarkingVerifier(heap) {}
 
-static void VerifyMarking(Heap* heap) {
-  VerifyMarking(heap->old_space());
-  VerifyMarking(heap->code_space());
-  VerifyMarking(heap->map_space());
-  VerifyMarking(heap->new_space());
-
-  VerifyMarkingVisitor visitor;
+  void Run() override {
+    VerifyRoots(VISIT_ONLY_STRONG);
+    VerifyMarking(heap_->new_space());
+    VerifyMarking(heap_->old_space());
+    VerifyMarking(heap_->code_space());
+    VerifyMarking(heap_->map_space());
 
-  LargeObjectIterator it(heap->lo_space());
+    LargeObjectIterator it(heap_->lo_space());
     for (HeapObject* obj = it.Next(); obj != NULL; obj = it.Next()) {
-    if (ObjectMarking::IsBlackOrGrey(obj)) {
-      obj->Iterate(&visitor);
+      if (ObjectMarking::IsBlackOrGrey(obj, marking_state(obj))) {
+        obj->Iterate(this);
+      }
     }
   }
 
-  heap->IterateStrongRoots(&visitor, VISIT_ONLY_STRONG);
-}
+ protected:
+  MarkingState marking_state(MemoryChunk* chunk) override {
+    return MarkingState::FromPageInternal(chunk);
+  }
+
+  MarkingState marking_state(HeapObject* object) {
+    return marking_state(Page::FromAddress(object->address()));
+  }
+
+  void VisitPointers(Object** start, Object** end) override {
+    for (Object** current = start; current < end; current++) {
+      if ((*current)->IsHeapObject()) {
+        HeapObject* object = HeapObject::cast(*current);
+        CHECK(ObjectMarking::IsBlackOrGrey(object, marking_state(object)));
+      }
+    }
+  }
+
+  void VisitEmbeddedPointer(RelocInfo* rinfo) override {
+    DCHECK(rinfo->rmode() == RelocInfo::EMBEDDED_OBJECT);
+    if (!rinfo->host()->IsWeakObject(rinfo->target_object())) {
+      Object* p = rinfo->target_object();
+      VisitPointer(&p);
+    }
+  }
+
+  void VisitCell(RelocInfo* rinfo) override {
+    Code* code = rinfo->host();
+    DCHECK(rinfo->rmode() == RelocInfo::CELL);
+    if (!code->IsWeakObject(rinfo->target_cell())) {
+      ObjectVisitor::VisitCell(rinfo);
+    }
+  }
+};
+
+class YoungGenerationMarkingVerifier : public MarkingVerifier {
+ public:
+  explicit YoungGenerationMarkingVerifier(Heap* heap) : MarkingVerifier(heap) {}
 
+  MarkingState marking_state(MemoryChunk* chunk) override {
+    return MarkingState::FromPageExternal(chunk);
+  }
+
+  MarkingState marking_state(HeapObject* object) {
+    return marking_state(Page::FromAddress(object->address()));
+  }
+
+  void Run() override {
+    VerifyRoots(VISIT_ALL_IN_SCAVENGE);
+    VerifyMarking(heap_->new_space());
+  }
+
+  void VisitPointers(Object** start, Object** end) override {
+    for (Object** current = start; current < end; current++) {
+      if ((*current)->IsHeapObject()) {
+        HeapObject* object = HeapObject::cast(*current);
+        if (!heap_->InNewSpace(object)) return;
+        CHECK(ObjectMarking::IsBlackOrGrey(object, marking_state(object)));
+      }
+    }
+  }
+};
 
 class VerifyEvacuationVisitor : public ObjectVisitor {
  public:
@@ -310,7 +364,8 @@ void MarkCompactCollector::CollectGarbage() {
 
 #ifdef VERIFY_HEAP
   if (FLAG_verify_heap) {
-    VerifyMarking(heap_);
+    FullMarkingVerifier verifier(heap());
+    verifier.Run();
   }
 #endif
 
@@ -2354,7 +2409,16 @@ void MinorMarkCompactCollector::EmptyMarkingDeque() {
   }
 }
 
-void MinorMarkCompactCollector::CollectGarbage() { MarkLiveObjects(); }
+void MinorMarkCompactCollector::CollectGarbage() {
+  MarkLiveObjects();
+
+#ifdef VERIFY_HEAP
+  if (FLAG_verify_heap) {
+    YoungGenerationMarkingVerifier verifier(heap());
+    verifier.Run();
+  }
+#endif  // VERIFY_HEAP
+}
 
 void MarkCompactCollector::MarkLiveObjects() {
   TRACE_GC(heap()->tracer(), GCTracer::Scope::MC_MARK);