Split an allocation policy into an allocator and a deallocator.

src/list.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 28 matching lines @@
 // using the STL because we want full control over space and speed of
 // the code. This implementation is based on code by Robert Griesemer
 // and Rob Pike.
 //
 // The list is parameterized by the type of its elements (T) and by an
 // allocation policy (P). The policy is used for allocating lists in
 // the C free store or the zone; see zone.h.
 
 // Forward defined as
 // template <typename T, class P = FreeStoreAllocationPolicy> class List;
-template <typename T, class P>
+template <typename T, class AllocationPolicy>
 class List {
  public:
-  List() { Initialize(0); }
-  INLINE(explicit List(int capacity)) { Initialize(capacity); }
+  typedef typename AllocationPolicy::Allocator Allocator;
+  typedef typename AllocationPolicy::Deallocator Deallocator;
+  explicit List(Allocator allocator = Allocator(),
+                Deallocator deallocator = Deallocator())
+      : deallocator_(deallocator) {
+    Initialize(0, allocator);
+  }
+  INLINE(explicit List(int capacity, Allocator allocator = Allocator(),
+                       Deallocator deallocator = Deallocator()))
+      : deallocator_(deallocator) {
+    Initialize(capacity, allocator);
+  }
   INLINE(~List()) { DeleteData(data_); }
 
   // Deallocates memory used by the list and leaves the list in a consistent
   // empty state.
   void Free() {
     DeleteData(data_);
     Initialize(0);
   }
 
-  INLINE(void* operator new(size_t size)) {
-      return P::New(static_cast<int>(size));
+  INLINE(void* operator new(size_t size, Allocator allocator = Allocator())) {
+    return allocator.New(static_cast<int>(size));
   }
-  INLINE(void operator delete(void* p, size_t)) { return P::Delete(p); }
+  INLINE(void operator delete(void* p)) {
+    reinterpret_cast<List*>(p)->deallocator_.Delete(p);
+  }
 
   // Returns a reference to the element at index i.  This reference is
   // not safe to use after operations that can change the list's
   // backing store (e.g. Add).
   inline T& operator[](int i) const {
     ASSERT(0 <= i);
     ASSERT(i < length_);
     return data_[i];
   }
   inline T& at(int i) const { return operator[](i); }
   inline T& last() const { return at(length_ - 1); }
   inline T& first() const { return at(0); }
 
   INLINE(bool is_empty() const) { return length_ == 0; }
   INLINE(int length() const) { return length_; }
   INLINE(int capacity() const) { return capacity_; }
 
   Vector<T> ToVector() const { return Vector<T>(data_, length_); }
 
   Vector<const T> ToConstVector() { return Vector<const T>(data_, length_); }
 
   // Adds a copy of the given 'element' to the end of the list,
   // expanding the list if necessary.
-  void Add(const T& element);
+  void Add(const T& element, Allocator allocator = Allocator());
 
   // Add all the elements from the argument list to this list.
-  void AddAll(const List<T, P>& other);
+  void AddAll(const List<T, AllocationPolicy>& other,
+              Allocator allocator = Allocator());
 
   // Add all the elements from the vector to this list.
-  void AddAll(const Vector<T>& other);
+  void AddAll(const Vector<T>& other, Allocator allocator = Allocator());
 
   // Inserts the element at the specific index.
-  void InsertAt(int index, const T& element);
+  void InsertAt(int index, const T& element, Allocator allocator = Allocator());
 
   // Added 'count' elements with the value 'value' and returns a
   // vector that allows access to the elements.  The vector is valid
   // until the next change is made to this list.
-  Vector<T> AddBlock(T value, int count);
+  Vector<T> AddBlock(T value, int count, Allocator allocator = Allocator());
 
   // Removes the i'th element without deleting it even if T is a
   // pointer type; moves all elements above i "down". Returns the
   // removed element.  This function's complexity is linear in the
   // size of the list.
   T Remove(int i);
 
   // Remove the given element from the list. Returns whether or not
   // the input is included in the list in the first place.
   bool RemoveElement(const T& elm);
 
   // Removes the last element without deleting it even if T is a
   // pointer type. Returns the removed element.
   INLINE(T RemoveLast()) { return Remove(length_ - 1); }
 
   // Deletes current list contents and allocates space for 'length' elements.
-  INLINE(void Allocate(int length));
+  INLINE(void Allocate(int length, Allocator allocator = Allocator()));
 
   // Clears the list by setting the length to zero. Even if T is a
   // pointer type, clearing the list doesn't delete the entries.
   INLINE(void Clear());
 
   // Drops all but the first 'pos' elements from the list.
   INLINE(void Rewind(int pos));
 
   // Drop the last 'count' elements from the list.
   INLINE(void RewindBy(int count)) { Rewind(length_ - count); }
 
   bool Contains(const T& elm) const;
   int CountOccurrences(const T& elm, int start, int end) const;
 
   // Iterate through all list entries, starting at index 0.
   void Iterate(void (*callback)(T* x));
   template<class Visitor>
   void Iterate(Visitor* visitor);
 
   // Sort all list entries (using QuickSort)
   void Sort(int (*cmp)(const T* x, const T* y));
   void Sort();
 
-  INLINE(void Initialize(int capacity));
+  INLINE(void Initialize(int capacity, Allocator allocator = Allocator()));
 
  private:
   T* data_;
   int capacity_;
   int length_;
+  Deallocator deallocator_;
 
-  INLINE(T* NewData(int n))  { return static_cast<T*>(P::New(n * sizeof(T))); }
-  INLINE(void DeleteData(T* data))  { P::Delete(data); }
+  INLINE(T* NewData(int n, Allocator allocator))  {
+    return static_cast<T*>(allocator.New(n * sizeof(T)));
+  }
+  INLINE(void DeleteData(T* data))  {
+    deallocator_.Delete(data);
+  }
 
   // Increase the capacity of a full list, and add an element.
   // List must be full already.
-  void ResizeAdd(const T& element);
+  void ResizeAdd(const T& element, Allocator alloc);
 
   // Inlined implementation of ResizeAdd, shared by inlined and
   // non-inlined versions of ResizeAdd.
-  void ResizeAddInternal(const T& element);
+  void ResizeAddInternal(const T& element, Allocator alloc);
 
   // Resize the list.
-  void Resize(int new_capacity);
+  void Resize(int new_capacity, Allocator alloc);
 
   DISALLOW_COPY_AND_ASSIGN(List);
 };
 
 class Map;
 class Code;
 template<typename T> class Handle;
 typedef List<Map*> MapList;
 typedef List<Code*> CodeList;
 typedef List<Handle<Map> > MapHandleList;
 typedef List<Handle<Code> > CodeHandleList;
 
 // Perform binary search for an element in an already sorted
 // list. Returns the index of the element of -1 if it was not found.
 // |cmp| is a predicate that takes a pointer to an element of the List
 // and returns +1 if it is greater, -1 if it is less than the element
 // being searched.
 template <typename T, class P>
 int SortedListBSearch(const List<T>& list, P cmp);
 template <typename T>
 int SortedListBSearch(const List<T>& list, T elem);
 
 
 } }  // namespace v8::internal
 
 
 #endif  // V8_LIST_H_