1// Copyright 2006-2009 the V8 project authors. All rights reserved.
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3// modification, are permitted provided that the following conditions are
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27
28#ifndef V8_LIST_H_
29#define V8_LIST_H_
30
31namespace v8 {
32namespace internal {
33
34
35// ----------------------------------------------------------------------------
36// The list is a template for very light-weight lists. We are not
37// using the STL because we want full control over space and speed of
38// the code. This implementation is based on code by Robert Griesemer
39// and Rob Pike.
40//
41// The list is parameterized by the type of its elements (T) and by an
42// allocation policy (P). The policy is used for allocating lists in
43// the C free store or the zone; see zone.h.
44
45// Forward defined as
46// template <typename T, class P = FreeStoreAllocationPolicy> class List;
47template <typename T, class P>
48class List {
49 public:
50
51  List() { Initialize(0); }
52  INLINE(explicit List(int capacity)) { Initialize(capacity); }
53  INLINE(~List()) { DeleteData(data_); }
54
55  // Deallocates memory used by the list and leaves the list in a consistent
56  // empty state.
57  void Free() {
58    DeleteData(data_);
59    Initialize(0);
60  }
61
62  INLINE(void* operator new(size_t size)) {
63      return P::New(static_cast<int>(size));
64  }
65  INLINE(void operator delete(void* p, size_t)) { return P::Delete(p); }
66
67  // Returns a reference to the element at index i.  This reference is
68  // not safe to use after operations that can change the list's
69  // backing store (eg, Add).
70  inline T& operator[](int i) const  {
71    ASSERT(0 <= i);
72    ASSERT(i < length_);
73    return data_[i];
74  }
75  inline T& at(int i) const  { return operator[](i); }
76  inline T& last() const { return at(length_ - 1); }
77  inline T& first() const { return at(0); }
78
79  INLINE(bool is_empty() const) { return length_ == 0; }
80  INLINE(int length() const) { return length_; }
81  INLINE(int capacity() const) { return capacity_; }
82
83  Vector<T> ToVector() { return Vector<T>(data_, length_); }
84
85  Vector<const T> ToConstVector() { return Vector<const T>(data_, length_); }
86
87  // Adds a copy of the given 'element' to the end of the list,
88  // expanding the list if necessary.
89  void Add(const T& element);
90
91  // Add all the elements from the argument list to this list.
92  void AddAll(const List<T, P>& other);
93
94  // Added 'count' elements with the value 'value' and returns a
95  // vector that allows access to the elements.  The vector is valid
96  // until the next change is made to this list.
97  Vector<T> AddBlock(T value, int count);
98
99  // Removes the i'th element without deleting it even if T is a
100  // pointer type; moves all elements above i "down". Returns the
101  // removed element.  This function's complexity is linear in the
102  // size of the list.
103  T Remove(int i);
104
105  // Removes the last element without deleting it even if T is a
106  // pointer type. Returns the removed element.
107  INLINE(T RemoveLast()) { return Remove(length_ - 1); }
108
109  // Clears the list by setting the length to zero. Even if T is a
110  // pointer type, clearing the list doesn't delete the entries.
111  INLINE(void Clear());
112
113  // Drops all but the first 'pos' elements from the list.
114  INLINE(void Rewind(int pos));
115
116  bool Contains(const T& elm);
117
118  // Iterate through all list entries, starting at index 0.
119  void Iterate(void (*callback)(T* x));
120
121  // Sort all list entries (using QuickSort)
122  void Sort(int (*cmp)(const T* x, const T* y));
123  void Sort();
124
125  INLINE(void Initialize(int capacity));
126
127 private:
128  T* data_;
129  int capacity_;
130  int length_;
131
132  INLINE(T* NewData(int n))  { return static_cast<T*>(P::New(n * sizeof(T))); }
133  INLINE(void DeleteData(T* data))  { P::Delete(data); }
134
135  // Increase the capacity of a full list, and add an element.
136  // List must be full already.
137  void ResizeAdd(const T& element);
138
139  // Inlined implementation of ResizeAdd, shared by inlined and
140  // non-inlined versions of ResizeAdd.
141  void ResizeAddInternal(const T& element);
142
143  // Resize the list.
144  void Resize(int new_capacity);
145
146  DISALLOW_COPY_AND_ASSIGN(List);
147};
148
149class FrameElement;
150
151// Add() is inlined, ResizeAdd() called by Add() is inlined except for
152// Lists of FrameElements, and ResizeAddInternal() is inlined in ResizeAdd().
153template <>
154void List<FrameElement,
155          FreeStoreAllocationPolicy>::ResizeAdd(const FrameElement& element);
156
157} }  // namespace v8::internal
158
159#endif  // V8_LIST_H_
160