[heap] Ensure consistency between store buffer mode and moving all entries to remembered set.

BUG=chromium:673308

Review-Url: https://codereview.chromium.org/2696563003
Cr-Commit-Position: refs/heads/master@{#43159}

src/heap/heap.cc

@@ -295,7 +295,6 @@ GarbageCollector Heap::SelectGarbageCollector(AllocationSpace space,
 
 void Heap::SetGCState(HeapState state) {
   gc_state_ = state;
-  store_buffer_->SetMode(gc_state_);
 }
 
 // TODO(1238405): Combine the infrastructure for --heap-stats and
@@ -447,7 +446,6 @@ void Heap::GarbageCollectionPrologue() {
   }
   CheckNewSpaceExpansionCriteria();
   UpdateNewSpaceAllocationCounter();
-  store_buffer()->MoveAllEntriesToRememberedSet();
 }
 
 size_t Heap::SizeOfObjects() {
@@ -515,6 +513,22 @@ void Heap::MergeAllocationSitePretenuringFeedback(
   }
 }
 
+class Heap::SkipStoreBufferScope {
+ public:
+  explicit SkipStoreBufferScope(StoreBuffer* store_buffer)
+      : store_buffer_(store_buffer) {
+    store_buffer_->MoveAllEntriesToRememberedSet();
+    store_buffer_->SetMode(StoreBuffer::IN_GC);
+  }
+
+  ~SkipStoreBufferScope() {
+    DCHECK(store_buffer_->Empty());
+    store_buffer_->SetMode(StoreBuffer::NOT_IN_GC);
+  }
+
+ private:
+  StoreBuffer* store_buffer_;
+};
 
 class Heap::PretenuringScope {
  public:
@@ -1324,6 +1338,7 @@ bool Heap::PerformGarbageCollection(
 
   {
     Heap::PretenuringScope pretenuring_scope(this);
+    Heap::SkipStoreBufferScope skip_store_buffer_scope(store_buffer_);
 
     switch (collector) {
       case MARK_COMPACTOR:

src/heap/heap.h

@@ -1523,6 +1523,7 @@ class Heap {
       GarbageCollectionReason gc_reason);
 
  private:
+  class SkipStoreBufferScope;
   class PretenuringScope;
 
   // External strings table is a place where all external strings are

src/heap/store-buffer.cc

@@ -16,7 +16,11 @@ namespace v8 {
 namespace internal {
 
 StoreBuffer::StoreBuffer(Heap* heap)
-    : heap_(heap), top_(nullptr), current_(0), virtual_memory_(nullptr) {
+    : heap_(heap),
+      top_(nullptr),
+      current_(0),
+      mode_(NOT_IN_GC),
+      virtual_memory_(nullptr) {
   for (int i = 0; i < kStoreBuffers; i++) {
     start_[i] = nullptr;
     limit_[i] = nullptr;

src/heap/store-buffer.h

@@ -24,6 +24,8 @@ namespace internal {
 // slots are moved to the remembered set.
 class StoreBuffer {
  public:
+  enum StoreBufferMode { IN_GC, NOT_IN_GC };
+
   static const int kStoreBufferSize = 1 << (11 + kPointerSizeLog2);
   static const int kStoreBufferMask = kStoreBufferSize - 1;
   static const int kStoreBuffers = 2;
@@ -74,7 +76,7 @@ class StoreBuffer {
                                             Address start, Address end) {
     // In GC the store buffer has to be empty at any time.
     DCHECK(store_buffer->Empty());
-    DCHECK(store_buffer->heap()->gc_state() != Heap::NOT_IN_GC);
+    DCHECK(store_buffer->mode() != StoreBuffer::NOT_IN_GC);
     Page* page = Page::FromAddress(start);
     if (end) {
       RememberedSet<OLD_TO_NEW>::RemoveRange(page, start, end,
@@ -86,7 +88,7 @@ class StoreBuffer {
 
   static void DeleteDuringRuntime(StoreBuffer* store_buffer, Address start,
                                   Address end) {
-    DCHECK(store_buffer->heap()->gc_state() == Heap::NOT_IN_GC);
+    DCHECK(store_buffer->mode() == StoreBuffer::NOT_IN_GC);
     store_buffer->InsertDeletionIntoStoreBuffer(start, end);
   }
 
@@ -102,12 +104,12 @@ class StoreBuffer {
 
   static void InsertDuringGarbageCollection(StoreBuffer* store_buffer,
                                             Address slot) {
-    DCHECK(store_buffer->heap()->gc_state() != Heap::NOT_IN_GC);
+    DCHECK(store_buffer->mode() != StoreBuffer::NOT_IN_GC);
     RememberedSet<OLD_TO_NEW>::Insert(Page::FromAddress(slot), slot);
   }
 
   static void InsertDuringRuntime(StoreBuffer* store_buffer, Address slot) {
-    DCHECK(store_buffer->heap()->gc_state() == Heap::NOT_IN_GC);
+    DCHECK(store_buffer->mode() == StoreBuffer::NOT_IN_GC);
     store_buffer->InsertIntoStoreBuffer(slot);
   }
 
@@ -126,8 +128,9 @@ class StoreBuffer {
     insertion_callback(this, slot);
   }
 
-  void SetMode(Heap::HeapState state) {
-    if (state == Heap::NOT_IN_GC) {
+  void SetMode(StoreBufferMode mode) {
+    mode_ = mode;
+    if (mode == NOT_IN_GC) {
       insertion_callback = &InsertDuringRuntime;
       deletion_callback = &DeleteDuringRuntime;
     } else {
@@ -175,6 +178,8 @@ class StoreBuffer {
     DISALLOW_COPY_AND_ASSIGN(Task);
   };
 
+  StoreBufferMode mode() const { return mode_; }
+
   void FlipStoreBuffers();
 
   Heap* heap_;
@@ -198,6 +203,11 @@ class StoreBuffer {
   // Points to the current buffer in use.
   int current_;
 
+  // During GC, entries are directly added to the remembered set without
+  // going through the store buffer. This is signaled by a special
+  // IN_GC mode.
+  StoreBufferMode mode_;
+
   base::VirtualMemory* virtual_memory_;
 
   // Callbacks are more efficient than reading out the gc state for every