File: ExecutableMemoryHandle.h

package info (click to toggle)
webkit2gtk 2.34.6-1~deb10u1
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 262,936 kB
  • sloc: cpp: 2,410,633; javascript: 191,866; ansic: 97,227; xml: 65,800; python: 30,274; ruby: 17,137; perl: 15,396; asm: 9,345; yacc: 2,309; sh: 1,660; lex: 1,293; java: 726; makefile: 106; pascal: 60
file content (113 lines) | stat: -rw-r--r-- 3,622 bytes parent folder | download
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
/*
 * Copyright (C) 2021 Apple 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:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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. 
 */

#pragma once

#if USE(LIBPAS_JIT_HEAP)
#include <wtf/MetaAllocatorPtr.h>
#include <wtf/ThreadSafeRefCounted.h>
#include <bmalloc/jit_heap.h>
#else
#include <wtf/MetaAllocatorHandle.h>
#endif

namespace JSC {

#if USE(LIBPAS_JIT_HEAP)
class ExecutableMemoryHandle : public ThreadSafeRefCounted<ExecutableMemoryHandle> {
    WTF_MAKE_FAST_ALLOCATED_WITH_HEAP_IDENTIFIER(ExecutableMemoryHandle);

public:
    using MemoryPtr = MetaAllocatorPtr<WTF::HandleMemoryPtrTag>;

    // Don't call this directly - for proper accounting it's necessary to call
    // ExecutableAllocator::allocate().
    JS_EXPORT_PRIVATE static RefPtr<ExecutableMemoryHandle> createImpl(size_t sizeInBytes);

    JS_EXPORT_PRIVATE ~ExecutableMemoryHandle();

    MemoryPtr start() const
    {
        return m_start;
    }

    MemoryPtr end() const
    {
        return MemoryPtr::makeFromRawPointer(reinterpret_cast<void*>(endAsInteger()));
    }

    uintptr_t startAsInteger() const
    {
        return m_start.untaggedPtr<uintptr_t>();
    }

    uintptr_t endAsInteger() const
    {
        return startAsInteger() + sizeInBytes();
    }

    size_t sizeInBytes() const { return m_sizeInBytes; }

    bool containsIntegerAddress(uintptr_t address) const
    {
        uintptr_t startAddress = startAsInteger();
        uintptr_t endAddress = startAddress + sizeInBytes();
        return address >= startAddress && address < endAddress;
    }

    bool contains(void* address) const
    {
        return containsIntegerAddress(reinterpret_cast<uintptr_t>(address));
    }

    JS_EXPORT_PRIVATE void shrink(size_t newSizeInBytes);

    void* key() const
    {
        return m_start.untaggedPtr();
    }

    void dump(PrintStream& out) const
    {
        out.print(RawPointer(key()));
    }

private:
    ExecutableMemoryHandle(MemoryPtr start, size_t sizeInBytes)
        : m_sizeInBytes(sizeInBytes)
        , m_start(start)
    {
        ASSERT(sizeInBytes == m_sizeInBytes); // executable memory region does not exceed 4GB.
    }

    unsigned m_sizeInBytes;
    MemoryPtr m_start;
};
#else // USE(LIBPAS_JIT_HEAP) -> so start of !USE(LIBPAS_JIT_HEAP) case
typedef WTF::MetaAllocatorHandle ExecutableMemoryHandle;
#endif // USE(LIBPAS_JIT_HEAP) -> so end of !USE(LIBPAS_JIT_HEAP) case

} // namespace JSC