[heap] Refactor evacuation verifier

src/heap/mark-compact.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/heap/mark-compact.h"
 
 #include "src/base/atomicops.h"
 #include "src/base/bits.h"
 #include "src/base/sys-info.h"
 #include "src/code-stubs.h"
@@ skipping 25 matching lines @@
 
 const char* Marking::kWhiteBitPattern = "00";
 const char* Marking::kBlackBitPattern = "11";
 const char* Marking::kGreyBitPattern = "10";
 const char* Marking::kImpossibleBitPattern = "01";
 
 // The following has to hold in order for {ObjectMarking::MarkBitFrom} to not
 // produce invalid {kImpossibleBitPattern} in the marking bitmap by overlapping.
 STATIC_ASSERT(Heap::kMinObjectSizeInWords >= 2);
 
-
-// -------------------------------------------------------------------------
-// MarkCompactCollector
-
-MarkCompactCollector::MarkCompactCollector(Heap* heap)
-    :  // NOLINT
-      heap_(heap),
-      page_parallel_job_semaphore_(0),
-#ifdef DEBUG
-      state_(IDLE),
-#endif
-      was_marked_incrementally_(false),
-      evacuation_(false),
-      compacting_(false),
-      black_allocation_(false),
-      have_code_to_deoptimize_(false),
-      marking_deque_(heap),
-      code_flusher_(nullptr),
-      sweeper_(heap) {
-}
+// =============================================================================
+// Verifiers
+// =============================================================================
 
 #ifdef VERIFY_HEAP
+namespace {
+
 class MarkingVerifier : public ObjectVisitor {
  public:
   virtual void Run() = 0;
 
  protected:
   explicit MarkingVerifier(Heap* heap) : heap_(heap) {}
 
   virtual MarkingState marking_state(MemoryChunk* chunk) = 0;
 
   void VerifyRoots(VisitMode mode);
@@ skipping 135 matching lines @@
     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 {
+class EvacuationVerifier : public ObjectVisitor {
  public:
+  virtual void Run() = 0;
+
   void VisitPointers(Object** start, Object** end) override {
     for (Object** current = start; current < end; current++) {
       if ((*current)->IsHeapObject()) {
         HeapObject* object = HeapObject::cast(*current);
         CHECK(!MarkCompactCollector::IsOnEvacuationCandidate(object));
       }
     }
   }
+
+ protected:
+  explicit EvacuationVerifier(Heap* heap) : heap_(heap) {}
+
+  void VerifyRoots(VisitMode mode);
+  void VerifyEvacuationOnPage(Address start, Address end);
+  void VerifyEvacuation(NewSpace* new_space);
+  void VerifyEvacuation(PagedSpace* paged_space);
+
+  Heap* heap_;
 };
 
+void EvacuationVerifier::VerifyRoots(VisitMode mode) {
+  heap_->IterateStrongRoots(this, mode);
+}
 
-static void VerifyEvacuation(Page* page) {
-  VerifyEvacuationVisitor visitor;
-  HeapObjectIterator iterator(page);
-  for (HeapObject* heap_object = iterator.Next(); heap_object != NULL;
-       heap_object = iterator.Next()) {
-    // We skip free space objects.
-    if (!heap_object->IsFiller()) {
-      heap_object->Iterate(&visitor);
-    }
+void EvacuationVerifier::VerifyEvacuationOnPage(Address start, Address end) {
+  Address current = start;
+  while (current < end) {
+    HeapObject* object = HeapObject::FromAddress(current);
+    if (!object->IsFiller()) object->Iterate(this);
+    current += object->Size();
   }
 }
 
-
-static void VerifyEvacuation(NewSpace* space) {
-  VerifyEvacuationVisitor visitor;
+void EvacuationVerifier::VerifyEvacuation(NewSpace* space) {
   PageRange range(space->bottom(), space->top());
   for (auto it = range.begin(); it != range.end();) {
     Page* page = *(it++);
     Address current = page->area_start();
     Address limit = it != range.end() ? page->area_end() : space->top();
     CHECK(limit == space->top() || !page->Contains(space->top()));
-    while (current < limit) {
-      HeapObject* object = HeapObject::FromAddress(current);
-      object->Iterate(&visitor);
-      current += object->Size();
-    }
+    VerifyEvacuationOnPage(current, limit);
   }
 }
 
-
-static void VerifyEvacuation(Heap* heap, PagedSpace* space) {
-  if (FLAG_use_allocation_folding && (space == heap->old_space())) {
+void EvacuationVerifier::VerifyEvacuation(PagedSpace* space) {
+  if (FLAG_use_allocation_folding && (space == heap_->old_space())) {

[Michael Lippautz, 2017/04/04 11:21:42]

I just copied this part but with the current implementation for allocation
folding I see no reason why we would not be able to verify.

I will (try) to remove this in a separate CL.

     return;
   }
   for (Page* p : *space) {
     if (p->IsEvacuationCandidate()) continue;
-    VerifyEvacuation(p);
+    VerifyEvacuationOnPage(p->area_start(), p->area_end());
   }
 }
 
+class FullEvacuationVerifier : public EvacuationVerifier {
+ public:
+  explicit FullEvacuationVerifier(Heap* heap) : EvacuationVerifier(heap) {}
 
-static void VerifyEvacuation(Heap* heap) {
-  VerifyEvacuation(heap, heap->old_space());
-  VerifyEvacuation(heap, heap->code_space());
-  VerifyEvacuation(heap, heap->map_space());
-  VerifyEvacuation(heap->new_space());
+  void Run() override {
+    VerifyRoots(VISIT_ALL);
+    VerifyEvacuation(heap_->new_space());
+    VerifyEvacuation(heap_->old_space());
+    VerifyEvacuation(heap_->code_space());
+    VerifyEvacuation(heap_->map_space());
+  }
+};
 
-  VerifyEvacuationVisitor visitor;
-  heap->IterateStrongRoots(&visitor, VISIT_ALL);
-}
+}  // namespace
 #endif  // VERIFY_HEAP
 
+// =============================================================================
+// MarkCompactCollector
+// =============================================================================
+
+MarkCompactCollector::MarkCompactCollector(Heap* heap)
+    :  // NOLINT
+      heap_(heap),
+      page_parallel_job_semaphore_(0),
+#ifdef DEBUG
+      state_(IDLE),
+#endif
+      was_marked_incrementally_(false),
+      evacuation_(false),
+      compacting_(false),
+      black_allocation_(false),
+      have_code_to_deoptimize_(false),
+      marking_deque_(heap),
+      code_flusher_(nullptr),
+      sweeper_(heap) {
+}
 
 void MarkCompactCollector::SetUp() {
   DCHECK(strcmp(Marking::kWhiteBitPattern, "00") == 0);
   DCHECK(strcmp(Marking::kBlackBitPattern, "11") == 0);
   DCHECK(strcmp(Marking::kGreyBitPattern, "10") == 0);
   DCHECK(strcmp(Marking::kImpossibleBitPattern, "01") == 0);
   marking_deque()->SetUp();
 
   if (FLAG_flush_code) {
     code_flusher_ = new CodeFlusher(isolate());
@@ skipping 281 matching lines @@
 void MarkCompactCollector::EnsureSweepingCompleted() {
   if (!sweeper().sweeping_in_progress()) return;
 
   sweeper().EnsureCompleted();
   heap()->old_space()->RefillFreeList();
   heap()->code_space()->RefillFreeList();
   heap()->map_space()->RefillFreeList();
 
 #ifdef VERIFY_HEAP
   if (FLAG_verify_heap && !evacuation()) {
-    VerifyEvacuation(heap_);
+    FullEvacuationVerifier verifier(heap_);
+    verifier.Run();
   }
 #endif
 
   if (heap()->memory_allocator()->unmapper()->has_delayed_chunks())
     heap()->memory_allocator()->unmapper()->FreeQueuedChunks();
 }
 
 bool MarkCompactCollector::Sweeper::AreSweeperTasksRunning() {
   return num_sweeping_tasks_.Value() != 0;
 }
@@ skipping 3104 matching lines @@
     }
   }
 
   {
     TRACE_GC(heap()->tracer(), GCTracer::Scope::MC_EVACUATE_EPILOGUE);
     EvacuateEpilogue();
   }
 
 #ifdef VERIFY_HEAP
   if (FLAG_verify_heap && !sweeper().sweeping_in_progress()) {
-    VerifyEvacuation(heap());
+    FullEvacuationVerifier verifier(heap());
+    verifier.Run();
   }
 #endif
 }
 
 template <RememberedSetType type>
 class PointerUpdateJobTraits {
  public:
   typedef int PerPageData;  // Per page data is not used in this job.
   typedef int PerTaskData;  // Per task data is not used in this job.
 
@@ skipping 427 matching lines @@
       // The target is always in old space, we don't have to record the slot in
       // the old-to-new remembered set.
       DCHECK(!heap()->InNewSpace(target));
       RecordRelocSlot(host, &rinfo, target);
     }
   }
 }
 
 }  // namespace internal
 }  // namespace v8