1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
|
// Copyright 2010 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
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef V8_SPLAY_TREE_H_
#define V8_SPLAY_TREE_H_
namespace v8 {
namespace internal {
// A splay tree. The config type parameter encapsulates the different
// configurations of a concrete splay tree:
//
// typedef Key: the key type
// typedef Value: the value type
// static const kNoKey: the dummy key used when no key is set
// static const kNoValue: the dummy value used to initialize nodes
// int (Compare)(Key& a, Key& b) -> {-1, 0, 1}: comparison function
//
// The tree is also parameterized by an allocation policy
// (Allocator). The policy is used for allocating lists in the C free
// store or the zone; see zone.h.
// Forward defined as
// template <typename Config, class Allocator = FreeStoreAllocationPolicy>
// class SplayTree;
template <typename Config, class Allocator>
class SplayTree {
public:
typedef typename Config::Key Key;
typedef typename Config::Value Value;
class Locator;
SplayTree() : root_(NULL) { }
~SplayTree();
INLINE(void* operator new(size_t size)) {
return Allocator::New(static_cast<int>(size));
}
INLINE(void operator delete(void* p, size_t)) { return Allocator::Delete(p); }
// Inserts the given key in this tree with the given value. Returns
// true if a node was inserted, otherwise false. If found the locator
// is enabled and provides access to the mapping for the key.
bool Insert(const Key& key, Locator* locator);
// Looks up the key in this tree and returns true if it was found,
// otherwise false. If the node is found the locator is enabled and
// provides access to the mapping for the key.
bool Find(const Key& key, Locator* locator);
// Finds the mapping with the greatest key less than or equal to the
// given key.
bool FindGreatestLessThan(const Key& key, Locator* locator);
// Find the mapping with the greatest key in this tree.
bool FindGreatest(Locator* locator);
// Finds the mapping with the least key greater than or equal to the
// given key.
bool FindLeastGreaterThan(const Key& key, Locator* locator);
// Find the mapping with the least key in this tree.
bool FindLeast(Locator* locator);
// Move the node from one key to another.
bool Move(const Key& old_key, const Key& new_key);
// Remove the node with the given key from the tree.
bool Remove(const Key& key);
bool is_empty() { return root_ == NULL; }
// Perform the splay operation for the given key. Moves the node with
// the given key to the top of the tree. If no node has the given
// key, the last node on the search path is moved to the top of the
// tree.
void Splay(const Key& key);
class Node {
public:
Node(const Key& key, const Value& value)
: key_(key),
value_(value),
left_(NULL),
right_(NULL) { }
INLINE(void* operator new(size_t size)) {
return Allocator::New(static_cast<int>(size));
}
INLINE(void operator delete(void* p, size_t)) {
return Allocator::Delete(p);
}
Key key() { return key_; }
Value value() { return value_; }
Node* left() { return left_; }
Node* right() { return right_; }
private:
friend class SplayTree;
friend class Locator;
Key key_;
Value value_;
Node* left_;
Node* right_;
};
// A locator provides access to a node in the tree without actually
// exposing the node.
class Locator BASE_EMBEDDED {
public:
explicit Locator(Node* node) : node_(node) { }
Locator() : node_(NULL) { }
const Key& key() { return node_->key_; }
Value& value() { return node_->value_; }
void set_value(const Value& value) { node_->value_ = value; }
inline void bind(Node* node) { node_ = node; }
private:
Node* node_;
};
template <class Callback>
void ForEach(Callback* callback);
protected:
// Resets tree root. Existing nodes become unreachable.
void ResetRoot() { root_ = NULL; }
private:
// Search for a node with a given key. If found, root_ points
// to the node.
bool FindInternal(const Key& key);
// Inserts a node assuming that root_ is already set up.
void InsertInternal(int cmp, Node* node);
// Removes root_ node.
void RemoveRootNode(const Key& key);
template<class Callback>
class NodeToPairAdaptor BASE_EMBEDDED {
public:
explicit NodeToPairAdaptor(Callback* callback)
: callback_(callback) { }
void Call(Node* node) {
callback_->Call(node->key(), node->value());
}
private:
Callback* callback_;
DISALLOW_COPY_AND_ASSIGN(NodeToPairAdaptor);
};
class NodeDeleter BASE_EMBEDDED {
public:
NodeDeleter() { }
void Call(Node* node) { delete node; }
private:
DISALLOW_COPY_AND_ASSIGN(NodeDeleter);
};
template <class Callback>
void ForEachNode(Callback* callback);
Node* root_;
DISALLOW_COPY_AND_ASSIGN(SplayTree);
};
} } // namespace v8::internal
#endif // V8_SPLAY_TREE_H_
|
