[heap] Convert overapproximate weak closure phase into finalize incremental marking phase and revis…

src/heap/incremental-marking.h

 // 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.
 
 #ifndef V8_HEAP_INCREMENTAL_MARKING_H_
 #define V8_HEAP_INCREMENTAL_MARKING_H_
 
 #include "src/cancelable-task.h"
 #include "src/execution.h"
 #include "src/heap/incremental-marking-job.h"
 #include "src/objects.h"
 
 namespace v8 {
 namespace internal {
 
 // Forward declarations.
 class MarkBit;
 class PagedSpace;
 
 class IncrementalMarking {
  public:
   enum State { STOPPED, SWEEPING, MARKING, COMPLETE };
 
   enum CompletionAction { GC_VIA_STACK_GUARD, NO_GC_VIA_STACK_GUARD };
 
   enum ForceMarkingAction { FORCE_MARKING, DO_NOT_FORCE_MARKING };
 
   enum ForceCompletionAction { FORCE_COMPLETION, DO_NOT_FORCE_COMPLETION };
 
-  enum GCRequestType { COMPLETE_MARKING, OVERAPPROXIMATION };
+  enum GCRequestType { COMPLETE_MARKING, FINALIZATION };
 
   struct StepActions {
     StepActions(CompletionAction complete_action_,
                 ForceMarkingAction force_marking_,
                 ForceCompletionAction force_completion_)
         : completion_action(complete_action_),
           force_marking(force_marking_),
           force_completion(force_completion_) {}
 
     CompletionAction completion_action;
     ForceMarkingAction force_marking;
     ForceCompletionAction force_completion;
   };
 
   static StepActions IdleStepActions();
 
   explicit IncrementalMarking(Heap* heap);
 
   static void Initialize();
 
   State state() {
     DCHECK(state_ == STOPPED || FLAG_incremental_marking);
     return state_;
   }
 
   bool should_hurry() { return should_hurry_; }
   void set_should_hurry(bool val) { should_hurry_ = val; }
 
   bool weak_closure_was_overapproximated() const {
-    return weak_closure_was_overapproximated_;
+    return finalize_marking_completed_;
   }
 
   void SetWeakClosureWasOverApproximatedForTesting(bool val) {
-    weak_closure_was_overapproximated_ = val;
+    finalize_marking_completed_ = val;
   }
 
   inline bool IsStopped() { return state() == STOPPED; }
 
   INLINE(bool IsMarking()) { return state() >= MARKING; }
 
   inline bool IsMarkingIncomplete() { return state() == MARKING; }
 
   inline bool IsComplete() { return state() == COMPLETE; }
 
   inline bool IsReadyToOverApproximateWeakClosure() const {
-    return request_type_ == OVERAPPROXIMATION &&
-           !weak_closure_was_overapproximated_;
+    return request_type_ == FINALIZATION && !finalize_marking_completed_;
   }
 
   GCRequestType request_type() const { return request_type_; }
 
   bool CanBeActivated();
 
   bool ShouldActivateEvenWithoutIdleNotification();
 
   bool WasActivated();
 
   void Start(const char* reason = nullptr);
 
-  void MarkObjectGroups();
+  void FinalizeIncrementally();
 
   void UpdateMarkingDequeAfterScavenge();
 
   void Hurry();
 
   void Finalize();
 
   void Stop();
 
-  void OverApproximateWeakClosure(CompletionAction action);
+  void FinalizeMarking(CompletionAction action);
 
   void MarkingComplete(CompletionAction action);
 
   void Epilogue();
 
   // Performs incremental marking steps of step_size_in_bytes as long as
   // deadline_ins_ms is not reached. step_size_in_bytes can be 0 to compute
   // an estimate increment. Returns the remaining time that cannot be used
   // for incremental marking anymore because a single step would exceed the
   // deadline.
@@ skipping 105 matching lines @@
 
  private:
   int64_t SpaceLeftInOldSpace();
 
   void SpeedUp();
 
   void ResetStepCounters();
 
   void StartMarking();
 
+  void MarkRoots();
+  void MarkObjectGroups();
+
   void ActivateIncrementalWriteBarrier(PagedSpace* space);
   static void ActivateIncrementalWriteBarrier(NewSpace* space);
   void ActivateIncrementalWriteBarrier();
 
   static void DeactivateIncrementalWriteBarrierForSpace(PagedSpace* space);
   static void DeactivateIncrementalWriteBarrierForSpace(NewSpace* space);
   void DeactivateIncrementalWriteBarrier();
 
   static void SetOldSpacePageFlags(MemoryChunk* chunk, bool is_marking,
                                    bool is_compacting);
@@ skipping 23 matching lines @@
   intptr_t allocated_;
   intptr_t write_barriers_invoked_since_last_step_;
   size_t idle_marking_delay_counter_;
 
   int no_marking_scope_depth_;
 
   int unscanned_bytes_of_large_object_;
 
   bool was_activated_;
 
-  bool weak_closure_was_overapproximated_;
+  bool finalize_marking_completed_;
 
-  int weak_closure_approximation_rounds_;
+  int incremental_marking_finalization_rounds_;
 
   GCRequestType request_type_;
 
   IncrementalMarkingJob incremental_marking_job_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(IncrementalMarking);
 };
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_INCREMENTAL_MARKING_H_