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
169
170
171
172
173
174
175
176
177
178
179
180
|
//=== Registry.h - Linker-supported plugin registries -----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Defines a registry template for discovering pluggable modules.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_SUPPORT_REGISTRY_H
#define LLVM_SUPPORT_REGISTRY_H
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/iterator_range.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/DynamicLibrary.h"
#include <memory>
namespace llvm {
/// A simple registry entry which provides only a name, description, and
/// no-argument constructor.
template <typename T>
class SimpleRegistryEntry {
const char *Name, *Desc;
std::unique_ptr<T> (*Ctor)();
public:
SimpleRegistryEntry(const char *N, const char *D, std::unique_ptr<T> (*C)())
: Name(N), Desc(D), Ctor(C)
{}
const char *getName() const { return Name; }
const char *getDesc() const { return Desc; }
std::unique_ptr<T> instantiate() const { return Ctor(); }
};
/// A global registry used in conjunction with static constructors to make
/// pluggable components (like targets or garbage collectors) "just work" when
/// linked with an executable.
template <typename T>
class Registry {
public:
typedef SimpleRegistryEntry<T> entry;
class node;
class iterator;
private:
Registry() = delete;
friend class node;
static node *Head, *Tail;
public:
/// Node in linked list of entries.
///
class node {
friend class iterator;
friend Registry<T>;
node *Next;
const entry& Val;
public:
node(const entry &V) : Next(nullptr), Val(V) {}
};
static void add_node(node *N) {
if (Tail)
Tail->Next = N;
else
Head = N;
Tail = N;
}
/// Iterators for registry entries.
///
class iterator {
const node *Cur;
public:
explicit iterator(const node *N) : Cur(N) {}
bool operator==(const iterator &That) const { return Cur == That.Cur; }
bool operator!=(const iterator &That) const { return Cur != That.Cur; }
iterator &operator++() { Cur = Cur->Next; return *this; }
const entry &operator*() const { return Cur->Val; }
const entry *operator->() const { return &Cur->Val; }
};
static iterator begin() { return iterator(Head); }
static iterator end() { return iterator(nullptr); }
static iterator_range<iterator> entries() {
return make_range(begin(), end());
}
/// A static registration template. Use like such:
///
/// Registry<Collector>::Add<FancyGC>
/// X("fancy-gc", "Newfangled garbage collector.");
///
/// Use of this template requires that:
///
/// 1. The registered subclass has a default constructor.
template <typename V>
class Add {
entry Entry;
node Node;
static std::unique_ptr<T> CtorFn() { return make_unique<V>(); }
public:
Add(const char *Name, const char *Desc)
: Entry(Name, Desc, CtorFn), Node(Entry) {
add_node(&Node);
}
};
/// A dynamic import facility. This is used on Windows to
/// import the entries added in the plugin.
static void import(sys::DynamicLibrary &DL, const char *RegistryName) {
typedef void *(*GetRegistry)();
std::string Name("LLVMGetRegistry_");
Name.append(RegistryName);
GetRegistry Getter =
(GetRegistry)(intptr_t)DL.getAddressOfSymbol(Name.c_str());
if (Getter) {
// Call the getter function in order to get the full copy of the
// registry defined in the plugin DLL, and copy them over to the
// current Registry.
typedef std::pair<const node *, const node *> Info;
Info *I = static_cast<Info *>(Getter());
iterator begin(I->first);
iterator end(I->second);
for (++end; begin != end; ++begin) {
// This Node object needs to remain alive for the
// duration of the program.
add_node(new node(*begin));
}
}
}
/// Retrieve the data to be passed across DLL boundaries when
/// importing registries from another DLL on Windows.
static void *exportRegistry() {
static std::pair<const node *, const node *> Info(Head, Tail);
return &Info;
}
};
// Since these are defined in a header file, plugins must be sure to export
// these symbols.
template <typename T>
typename Registry<T>::node *Registry<T>::Head;
template <typename T>
typename Registry<T>::node *Registry<T>::Tail;
} // end namespace llvm
#ifdef LLVM_ON_WIN32
#define LLVM_EXPORT_REGISTRY(REGISTRY_CLASS) \
extern "C" { \
__declspec(dllexport) void *__cdecl LLVMGetRegistry_##REGISTRY_CLASS() { \
return REGISTRY_CLASS::exportRegistry(); \
} \
}
#define LLVM_IMPORT_REGISTRY(REGISTRY_CLASS, DL) \
REGISTRY_CLASS::import(DL, #REGISTRY_CLASS)
#else
#define LLVM_EXPORT_REGISTRY(REGISTRY_CLASS)
#define LLVM_IMPORT_REGISTRY(REGISTRY_CLASS, DL)
#endif
#endif // LLVM_SUPPORT_REGISTRY_H
|
