1 | // Copyright (C) 2016 The Qt Company Ltd. |
2 | // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only |
3 | |
4 | #ifndef QV4EXECUTABLEALLOCATOR_H |
5 | #define QV4EXECUTABLEALLOCATOR_H |
6 | |
7 | // |
8 | // W A R N I N G |
9 | // ------------- |
10 | // |
11 | // This file is not part of the Qt API. It exists purely as an |
12 | // implementation detail. This header file may change from version to |
13 | // version without notice, or even be removed. |
14 | // |
15 | // We mean it. |
16 | // |
17 | |
18 | #include <QMultiMap> |
19 | #include <QHash> |
20 | #include <QVector> |
21 | #include <QByteArray> |
22 | #include <QMutex> |
23 | |
24 | #include <QtQml/private/qtqmlglobal_p.h> |
25 | |
26 | namespace WTF { |
27 | class PageAllocation; |
28 | } |
29 | |
30 | QT_BEGIN_NAMESPACE |
31 | |
32 | namespace QV4 { |
33 | |
34 | class Q_QML_AUTOTEST_EXPORT ExecutableAllocator |
35 | { |
36 | public: |
37 | struct ChunkOfPages; |
38 | struct Allocation; |
39 | |
40 | ExecutableAllocator(); |
41 | ~ExecutableAllocator(); |
42 | |
43 | Allocation *allocate(size_t size); |
44 | void free(Allocation *allocation); |
45 | |
46 | struct Allocation |
47 | { |
48 | Allocation() |
49 | : size(0) |
50 | , free(true) |
51 | {} |
52 | |
53 | void *memoryStart() const; |
54 | size_t memorySize() const { return size; } |
55 | |
56 | void *exceptionHandlerStart() const; |
57 | size_t exceptionHandlerSize() const; |
58 | |
59 | void *codeStart() const; |
60 | |
61 | void invalidate() { addr = 0; } |
62 | bool isValid() const { return addr != 0; } |
63 | void deallocate(ExecutableAllocator *allocator); |
64 | |
65 | private: |
66 | ~Allocation() {} |
67 | |
68 | friend class ExecutableAllocator; |
69 | |
70 | Allocation *split(size_t dividingSize); |
71 | bool mergeNext(ExecutableAllocator *allocator); |
72 | bool mergePrevious(ExecutableAllocator *allocator); |
73 | |
74 | quintptr addr = 0; |
75 | uint size : 31; // More than 2GB of function code? nah :) |
76 | uint free : 1; |
77 | Allocation *next = nullptr; |
78 | Allocation *prev = nullptr; |
79 | }; |
80 | |
81 | // for debugging / unit-testing |
82 | int freeAllocationCount() const { return freeAllocations.size(); } |
83 | int chunkCount() const { return chunks.size(); } |
84 | |
85 | struct ChunkOfPages |
86 | { |
87 | ChunkOfPages() |
88 | |
89 | {} |
90 | ~ChunkOfPages(); |
91 | |
92 | WTF::PageAllocation *pages = nullptr; |
93 | Allocation *firstAllocation = nullptr; |
94 | |
95 | bool contains(Allocation *alloc) const; |
96 | }; |
97 | |
98 | ChunkOfPages *chunkForAllocation(Allocation *allocation) const; |
99 | |
100 | private: |
101 | QMultiMap<size_t, Allocation*> freeAllocations; |
102 | QMap<quintptr, ChunkOfPages*> chunks; |
103 | mutable QRecursiveMutex mutex; |
104 | }; |
105 | |
106 | } |
107 | |
108 | QT_END_NAMESPACE |
109 | |
110 | #endif // QV4EXECUTABLEALLOCATOR_H |
111 | |