-
Notifications
You must be signed in to change notification settings - Fork 30
/
alignalloc.h
169 lines (134 loc) · 4.25 KB
/
alignalloc.h
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
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
#pragma once
#include <cstddef>
#include <cstdint>
#include <cstdlib>
#include <utility>
#include <type_traits>
#include <stdexcept>
// https://stackoverflow.com/questions/12942548/making-stdvector-allocate-aligned-memory
namespace detail {
void* allocate_aligned_memory(size_t align, size_t size) {
return std::aligned_alloc(align, size);
}
void deallocate_aligned_memory(void* ptr) noexcept {
std::free(ptr);
}
}
template <typename T, size_t Align = 64>
class AlignedAllocator;
template <size_t Align>
class AlignedAllocator<void, Align>
{
public:
typedef void* pointer;
typedef const void* const_pointer;
typedef void value_type;
template <class U> struct rebind { typedef AlignedAllocator<U, Align> other; };
};
template <typename T, size_t Align>
class AlignedAllocator
{
public:
typedef T value_type;
typedef T* pointer;
typedef const T* const_pointer;
typedef T& reference;
typedef const T& const_reference;
typedef size_t size_type;
typedef ptrdiff_t difference_type;
typedef std::true_type propagate_on_container_move_assignment;
template <class U>
struct rebind { typedef AlignedAllocator<U, Align> other; };
public:
AlignedAllocator() noexcept
{}
template <class U>
AlignedAllocator(const AlignedAllocator<U, Align>&) noexcept
{}
size_type
max_size() const noexcept
{ return (size_type(~0) - size_type(Align)) / sizeof(T); }
pointer
address(reference x) const noexcept
{ return std::addressof(x); }
const_pointer
address(const_reference x) const noexcept
{ return std::addressof(x); }
pointer
allocate(size_type n, typename AlignedAllocator<void, Align>::const_pointer = 0)
{
const size_type alignment = static_cast<size_type>( Align );
void* ptr = detail::allocate_aligned_memory(alignment , n * sizeof(T));
if (ptr == nullptr) {
throw std::bad_alloc();
}
return reinterpret_cast<pointer>(ptr);
}
void
deallocate(pointer p, size_type) noexcept
{ return detail::deallocate_aligned_memory(p); }
template <class U, class ...Args>
void
construct(U* p, Args&&... args)
{ ::new(reinterpret_cast<void*>(p)) U(std::forward<Args>(args)...); }
void
destroy(pointer p)
{ p->~T(); }
};
template <typename T, size_t Align>
class AlignedAllocator<const T, Align>
{
public:
typedef T value_type;
typedef const T* pointer;
typedef const T* const_pointer;
typedef const T& reference;
typedef const T& const_reference;
typedef size_t size_type;
typedef ptrdiff_t difference_type;
typedef std::true_type propagate_on_container_move_assignment;
template <class U>
struct rebind { typedef AlignedAllocator<U, Align> other; };
public:
AlignedAllocator() noexcept
{}
template <class U>
AlignedAllocator(const AlignedAllocator<U, Align>&) noexcept
{}
size_type
max_size() const noexcept
{ return (size_type(~0) - size_type(Align)) / sizeof(T); }
const_pointer
address(const_reference x) const noexcept
{ return std::addressof(x); }
pointer
allocate(size_type n, typename AlignedAllocator<void, Align>::const_pointer = 0)
{
const size_type alignment = static_cast<size_type>( Align );
void* ptr = detail::allocate_aligned_memory(alignment , n * sizeof(T));
if (ptr == nullptr) {
throw std::bad_alloc();
}
return reinterpret_cast<pointer>(ptr);
}
void
deallocate(pointer p, size_type) noexcept
{ return detail::deallocate_aligned_memory(p); }
template <class U, class ...Args>
void
construct(U* p, Args&&... args)
{ ::new(reinterpret_cast<void*>(p)) U(std::forward<Args>(args)...); }
void
destroy(pointer p)
{ p->~T(); }
};
template <typename T, size_t TAlign, typename U, size_t UAlign>
inline
bool
operator== (const AlignedAllocator<T,TAlign>&, const AlignedAllocator<U, UAlign>&) noexcept
{ return TAlign == UAlign; }
template <typename T, size_t TAlign, typename U, size_t UAlign>
inline
bool
operator!= (const AlignedAllocator<T,TAlign>&, const AlignedAllocator<U, UAlign>&) noexcept
{ return TAlign != UAlign; }