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
|
/*
* Copyright (C) 2014 Google Inc. 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 THIRD_PARTY_BLINK_RENDERER_PLATFORM_HEAP_HEAP_LINKED_STACK_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_HEAP_HEAP_LINKED_STACK_H_
#include "third_party/blink/renderer/platform/heap/heap.h"
#include "third_party/blink/renderer/platform/heap/visitor.h"
#include "third_party/blink/renderer/platform/wtf/allocator.h"
namespace blink {
// HeapLinkedStack<> is an Oilpan-managed stack that avoids pre-allocation
// of memory and heap fragmentation.
//
// The API was originally implemented on the call stack by LinkedStack<>
// (now removed: https://codereview.chromium.org/2761853003/).
// See https://codereview.chromium.org/17314010 for the original use-case.
template <typename T>
class HeapLinkedStack : public GarbageCollected<HeapLinkedStack<T>> {
public:
HeapLinkedStack() : size_(0) {}
bool IsEmpty();
void Push(const T&);
const T& Peek();
void Pop();
size_t size();
void Trace(blink::Visitor* visitor) {
for (Node* current = head_; current; current = current->next_)
visitor->Trace(current);
}
private:
class Node : public GarbageCollected<Node> {
public:
Node(const T&, Node* next);
void Trace(blink::Visitor* visitor) { visitor->Trace(data_); }
T data_;
Member<Node> next_;
};
Member<Node> head_;
size_t size_;
};
template <typename T>
HeapLinkedStack<T>::Node::Node(const T& data, Node* next)
: data_(data), next_(next) {}
template <typename T>
inline bool HeapLinkedStack<T>::IsEmpty() {
return !head_;
}
template <typename T>
inline void HeapLinkedStack<T>::Push(const T& data) {
head_ = new Node(data, head_);
++size_;
}
template <typename T>
inline const T& HeapLinkedStack<T>::Peek() {
return head_->data_;
}
template <typename T>
inline void HeapLinkedStack<T>::Pop() {
DCHECK(head_);
DCHECK(size_);
head_ = head_->next_;
--size_;
}
template <typename T>
inline size_t HeapLinkedStack<T>::size() {
return size_;
}
template <typename T>
class TraceEagerlyTrait<HeapLinkedStack<T>> {
STATIC_ONLY(TraceEagerlyTrait);
public:
static const bool value = TraceEagerlyTrait<T>::value;
};
} // namespace blink
#endif // THIRD_PARTY_BLINK_RENDERER_PLATFORM_HEAP_HEAP_LINKED_STACK_H_
|
