1/*
2 * Copyright (C) 2015-2017 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#include <wtf/IndexKeyType.h>
29#include <wtf/Vector.h>
30
31namespace WTF {
32
33// This is a map for keys that have an index(). It's super efficient for BasicBlocks. It's only
34// efficient for Values if you don't create too many of these maps, since Values can have very
35// sparse indices and there are a lot of Values.
36
37template<typename Key, typename Value>
38class IndexMap {
39public:
40 IndexMap() = default;
41 IndexMap(IndexMap&&) = default;
42 IndexMap& operator=(IndexMap&&) = default;
43 IndexMap(const IndexMap&) = default;
44 IndexMap& operator=(const IndexMap&) = default;
45
46 template<typename... Args>
47 explicit IndexMap(size_t size, Args&&... args)
48 {
49 m_vector.fill(Value(std::forward<Args>(args)...), size);
50 }
51
52 template<typename... Args>
53 void resize(size_t size, Args&&... args)
54 {
55 m_vector.fill(Value(std::forward<Args>(args)...), size);
56 }
57
58 template<typename... Args>
59 void clear(Args&&... args)
60 {
61 m_vector.fill(Value(std::forward<Args>(args)...), m_vector.size());
62 }
63
64 size_t size() const { return m_vector.size(); }
65
66 Value& at(const Key& key)
67 {
68 return m_vector[IndexKeyType<Key>::index(key)];
69 }
70
71 const Value& at(const Key& key) const
72 {
73 return m_vector[IndexKeyType<Key>::index(key)];
74 }
75
76 Value& at(size_t index)
77 {
78 return m_vector[index];
79 }
80
81 const Value& at(size_t index) const
82 {
83 return m_vector[index];
84 }
85
86 Value& operator[](size_t index) { return at(index); }
87 const Value& operator[](size_t index) const { return at(index); }
88 Value& operator[](const Key& key) { return at(key); }
89 const Value& operator[](const Key& key) const { return at(key); }
90
91 template<typename PassedValue>
92 void append(const Key& key, PassedValue&& value)
93 {
94 RELEASE_ASSERT(IndexKeyType<Key>::index(key) == m_vector.size());
95 m_vector.append(std::forward<PassedValue>(value));
96 }
97
98private:
99 Vector<Value, 0, UnsafeVectorOverflow> m_vector;
100};
101
102} // namespace WTF
103
104using WTF::IndexMap;
105