Line data    Source code

       1             : // Copyright 2017 the V8 project authors. All rights reserved.
       2             : // Use of this source code is governed by a BSD-style license that can be
       3             : // found in the LICENSE file.
       4             : 
       5             : #ifndef V8_HEAP_INVALIDATED_SLOTS_H_
       6             : #define V8_HEAP_INVALIDATED_SLOTS_H_
       7             : 
       8             : #include <map>
       9             : #include <stack>
      10             : 
      11             : #include "src/allocation.h"
      12             : #include "src/base/atomic-utils.h"
      13             : #include "src/objects/heap-object.h"
      14             : #include "src/utils.h"
      15             : 
      16             : namespace v8 {
      17             : namespace internal {
      18             : 
      19             : // This data structure stores objects that went through object layout change
      20             : // that potentially invalidates slots recorded concurrently. The second part
      21             : // of each element is the size of the corresponding object before the layout
      22             : // change.
      23             : using InvalidatedSlots = std::map<HeapObject, int, Object::Comparer>;
      24             : 
      25             : // This class provides IsValid predicate that takes into account the set
      26             : // of invalidated objects in the given memory chunk.
      27             : // The sequence of queried slot must be non-decreasing. This allows fast
      28             : // implementation with complexity O(m*log(m) + n), where
      29             : // m is the number of invalidated objects in the memory chunk.
      30             : // n is the number of IsValid queries.
      31       13647 : class V8_EXPORT_PRIVATE InvalidatedSlotsFilter {
      32             :  public:
      33             :   explicit InvalidatedSlotsFilter(MemoryChunk* chunk);
      34             :   inline bool IsValid(Address slot);
      35             : 
      36             :  private:
      37             :   InvalidatedSlots::const_iterator iterator_;
      38             :   InvalidatedSlots::const_iterator iterator_end_;
      39             :   Address sentinel_;
      40             :   Address invalidated_start_;
      41             :   Address invalidated_end_;
      42             :   HeapObject invalidated_object_;
      43             :   int invalidated_object_size_;
      44             :   bool slots_in_free_space_are_valid_;
      45             :   InvalidatedSlots empty_;
      46             : #ifdef DEBUG
      47             :   Address last_slot_;
      48             : #endif
      49             : };
      50             : 
      51             : }  // namespace internal
      52             : }  // namespace v8
      53             : 
      54             : #endif  // V8_HEAP_INVALIDATED_SLOTS_H_