line |
stmt |
bran |
cond |
sub |
pod |
time |
code |
1
|
|
|
|
|
|
|
// Aligned memory buffer -*- C++ -*- |
2
|
|
|
|
|
|
|
|
3
|
|
|
|
|
|
|
// Copyright (C) 2013-2015 Free Software Foundation, Inc. |
4
|
|
|
|
|
|
|
// |
5
|
|
|
|
|
|
|
// This file is part of the GNU ISO C++ Library. This library is free |
6
|
|
|
|
|
|
|
// software; you can redistribute it and/or modify it under the |
7
|
|
|
|
|
|
|
// terms of the GNU General Public License as published by the |
8
|
|
|
|
|
|
|
// Free Software Foundation; either version 3, or (at your option) |
9
|
|
|
|
|
|
|
// any later version. |
10
|
|
|
|
|
|
|
|
11
|
|
|
|
|
|
|
// This library is distributed in the hope that it will be useful, |
12
|
|
|
|
|
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of |
13
|
|
|
|
|
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
14
|
|
|
|
|
|
|
// GNU General Public License for more details. |
15
|
|
|
|
|
|
|
|
16
|
|
|
|
|
|
|
// Under Section 7 of GPL version 3, you are granted additional |
17
|
|
|
|
|
|
|
// permissions described in the GCC Runtime Library Exception, version |
18
|
|
|
|
|
|
|
// 3.1, as published by the Free Software Foundation. |
19
|
|
|
|
|
|
|
|
20
|
|
|
|
|
|
|
// You should have received a copy of the GNU General Public License and |
21
|
|
|
|
|
|
|
// a copy of the GCC Runtime Library Exception along with this program; |
22
|
|
|
|
|
|
|
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
23
|
|
|
|
|
|
|
// . |
24
|
|
|
|
|
|
|
|
25
|
|
|
|
|
|
|
/** @file ext/aligned_buffer.h |
26
|
|
|
|
|
|
|
* This file is a GNU extension to the Standard C++ Library. |
27
|
|
|
|
|
|
|
*/ |
28
|
|
|
|
|
|
|
|
29
|
|
|
|
|
|
|
#ifndef _ALIGNED_BUFFER_H |
30
|
|
|
|
|
|
|
#define _ALIGNED_BUFFER_H 1 |
31
|
|
|
|
|
|
|
|
32
|
|
|
|
|
|
|
#pragma GCC system_header |
33
|
|
|
|
|
|
|
|
34
|
|
|
|
|
|
|
#if __cplusplus >= 201103L |
35
|
|
|
|
|
|
|
# include |
36
|
|
|
|
|
|
|
#else |
37
|
|
|
|
|
|
|
# include |
38
|
|
|
|
|
|
|
#endif |
39
|
|
|
|
|
|
|
|
40
|
|
|
|
|
|
|
namespace __gnu_cxx |
41
|
|
|
|
|
|
|
{ |
42
|
|
|
|
|
|
|
// A utility type containing a POD object that can hold an object of type |
43
|
|
|
|
|
|
|
// _Tp initialized via placement new or allocator_traits::construct. |
44
|
|
|
|
|
|
|
// Intended for use as a data member subobject, use __aligned_buffer for |
45
|
|
|
|
|
|
|
// complete objects. |
46
|
|
|
|
|
|
|
template |
47
|
|
|
|
|
|
|
struct __aligned_membuf |
48
|
|
|
|
|
|
|
{ |
49
|
|
|
|
|
|
|
// Target macro ADJUST_FIELD_ALIGN can produce different alignment for |
50
|
|
|
|
|
|
|
// types when used as class members. __aligned_membuf is intended |
51
|
|
|
|
|
|
|
// for use as a class member, so align the buffer as for a class member. |
52
|
|
|
|
|
|
|
struct _Tp2 { _Tp _M_t; }; |
53
|
|
|
|
|
|
|
|
54
|
|
|
|
|
|
|
alignas(__alignof__(_Tp2::_M_t)) unsigned char _M_storage[sizeof(_Tp)]; |
55
|
|
|
|
|
|
|
|
56
|
527
|
|
|
|
|
|
__aligned_membuf() = default; |
57
|
|
|
|
|
|
|
|
58
|
|
|
|
|
|
|
// Can be used to avoid value-initialization zeroing _M_storage. |
59
|
|
|
|
|
|
|
__aligned_membuf(std::nullptr_t) { } |
60
|
|
|
|
|
|
|
|
61
|
|
|
|
|
|
|
void* |
62
|
4490
|
|
|
|
|
|
_M_addr() noexcept |
63
|
4490
|
|
|
|
|
|
{ return static_cast(&_M_storage); } |
64
|
|
|
|
|
|
|
|
65
|
|
|
|
|
|
|
const void* |
66
|
3927
|
|
|
|
|
|
_M_addr() const noexcept |
67
|
3927
|
|
|
|
|
|
{ return static_cast(&_M_storage); } |
68
|
|
|
|
|
|
|
|
69
|
|
|
|
|
|
|
_Tp* |
70
|
4490
|
|
|
|
|
|
_M_ptr() noexcept |
71
|
4490
|
|
|
|
|
|
{ return static_cast<_Tp*>(_M_addr()); } |
72
|
|
|
|
|
|
|
|
73
|
|
|
|
|
|
|
const _Tp* |
74
|
3927
|
|
|
|
|
|
_M_ptr() const noexcept |
75
|
3927
|
|
|
|
|
|
{ return static_cast(_M_addr()); } |
76
|
|
|
|
|
|
|
}; |
77
|
|
|
|
|
|
|
|
78
|
|
|
|
|
|
|
// Similar to __aligned_membuf but aligned for complete objects, not members. |
79
|
|
|
|
|
|
|
// This type is used in , , |
80
|
|
|
|
|
|
|
// and , but ideally they would use __aligned_membuf |
81
|
|
|
|
|
|
|
// instead, as it has smaller size for some types on some targets. |
82
|
|
|
|
|
|
|
// This type is still used to avoid an ABI change. |
83
|
|
|
|
|
|
|
template |
84
|
|
|
|
|
|
|
struct __aligned_buffer |
85
|
|
|
|
|
|
|
: std::aligned_storage::value> |
86
|
|
|
|
|
|
|
{ |
87
|
|
|
|
|
|
|
typename |
88
|
|
|
|
|
|
|
std::aligned_storage::value>::type |
89
|
|
|
|
|
|
|
_M_storage; |
90
|
|
|
|
|
|
|
|
91
|
|
|
|
|
|
|
__aligned_buffer() = default; |
92
|
|
|
|
|
|
|
|
93
|
|
|
|
|
|
|
// Can be used to avoid value-initialization |
94
|
|
|
|
|
|
|
__aligned_buffer(std::nullptr_t) { } |
95
|
|
|
|
|
|
|
|
96
|
|
|
|
|
|
|
void* |
97
|
|
|
|
|
|
|
_M_addr() noexcept |
98
|
|
|
|
|
|
|
{ |
99
|
|
|
|
|
|
|
return static_cast(&_M_storage); |
100
|
|
|
|
|
|
|
} |
101
|
|
|
|
|
|
|
|
102
|
|
|
|
|
|
|
const void* |
103
|
|
|
|
|
|
|
_M_addr() const noexcept |
104
|
|
|
|
|
|
|
{ |
105
|
|
|
|
|
|
|
return static_cast(&_M_storage); |
106
|
|
|
|
|
|
|
} |
107
|
|
|
|
|
|
|
|
108
|
|
|
|
|
|
|
_Tp* |
109
|
|
|
|
|
|
|
_M_ptr() noexcept |
110
|
|
|
|
|
|
|
{ return static_cast<_Tp*>(_M_addr()); } |
111
|
|
|
|
|
|
|
|
112
|
|
|
|
|
|
|
const _Tp* |
113
|
|
|
|
|
|
|
_M_ptr() const noexcept |
114
|
|
|
|
|
|
|
{ return static_cast(_M_addr()); } |
115
|
|
|
|
|
|
|
}; |
116
|
|
|
|
|
|
|
|
117
|
|
|
|
|
|
|
} // namespace |
118
|
|
|
|
|
|
|
|
119
|
|
|
|
|
|
|
#endif /* _ALIGNED_BUFFER_H */ |