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
|
/*
* Copyright (C) 2008 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.
*/
#include "config.h"
#include "ExecutableAllocator.h"
#if ENABLE(ASSEMBLER)
namespace JSC {
size_t ExecutableAllocator::pageSize = 0;
#if ENABLE(EXECUTABLE_ALLOCATOR_DEMAND)
void ExecutableAllocator::intializePageSize()
{
#if OS(SYMBIAN) && CPU(ARMV5_OR_LOWER)
// The moving memory model (as used in ARMv5 and earlier platforms)
// on Symbian OS limits the number of chunks for each process to 16.
// To mitigate this limitation increase the pagesize to allocate
// fewer, larger chunks. Set the page size to 256 Kb to compensate
// for moving memory model limitation
ExecutableAllocator::pageSize = 256 * 1024;
#else
ExecutableAllocator::pageSize = WTF::pageSize();
#endif
}
ExecutablePool::Allocation ExecutablePool::systemAlloc(size_t size)
{
PageAllocation allocation = PageAllocation::allocate(size, OSAllocator::JSJITCodePages, EXECUTABLE_POOL_WRITABLE, true);
if (!allocation)
CRASH();
return allocation;
}
void ExecutablePool::systemRelease(ExecutablePool::Allocation& allocation)
{
allocation.deallocate();
}
bool ExecutableAllocator::isValid() const
{
return true;
}
bool ExecutableAllocator::underMemoryPressure()
{
return false;
}
size_t ExecutableAllocator::committedByteCount()
{
return 0;
}
#endif
#if ENABLE(ASSEMBLER_WX_EXCLUSIVE)
#if OS(WINDOWS) || OS(SYMBIAN)
#error "ASSEMBLER_WX_EXCLUSIVE not yet suported on this platform."
#endif
void ExecutableAllocator::reprotectRegion(void* start, size_t size, ProtectionSetting setting)
{
if (!pageSize)
intializePageSize();
// Calculate the start of the page containing this region,
// and account for this extra memory within size.
intptr_t startPtr = reinterpret_cast<intptr_t>(start);
intptr_t pageStartPtr = startPtr & ~(pageSize - 1);
void* pageStart = reinterpret_cast<void*>(pageStartPtr);
size += (startPtr - pageStartPtr);
// Round size up
size += (pageSize - 1);
size &= ~(pageSize - 1);
mprotect(pageStart, size, (setting == Writable) ? PROTECTION_FLAGS_RW : PROTECTION_FLAGS_RX);
}
#endif
#if CPU(ARM_TRADITIONAL) && OS(LINUX) && COMPILER(RVCT)
__asm void ExecutableAllocator::cacheFlush(void* code, size_t size)
{
ARM
push {r7}
add r1, r1, r0
mov r7, #0xf0000
add r7, r7, #0x2
mov r2, #0x0
svc #0x0
pop {r7}
bx lr
}
#endif
}
#endif // HAVE(ASSEMBLER)
|
