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
|
//===-- Redeclarable.h - Base for Decls that can be redeclared -*- C++ -*-====//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the Redeclarable interface.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_AST_REDECLARABLE_H
#define LLVM_CLANG_AST_REDECLARABLE_H
#include "llvm/ADT/PointerIntPair.h"
namespace clang {
/// \brief Provides common interface for the Decls that can be redeclared.
template<typename decl_type>
class Redeclarable {
protected:
struct DeclLink : public llvm::PointerIntPair<decl_type *, 1, bool> {
DeclLink(decl_type *D, bool isLatest)
: llvm::PointerIntPair<decl_type *, 1, bool>(D, isLatest) { }
typedef llvm::PointerIntPair<decl_type *, 1, bool> base_type;
bool NextIsPrevious() const { return base_type::getInt() == false; }
bool NextIsLatest() const { return base_type::getInt() == true; }
decl_type *getNext() const { return base_type::getPointer(); }
};
struct PreviousDeclLink : public DeclLink {
PreviousDeclLink(decl_type *D) : DeclLink(D, false) { }
};
struct LatestDeclLink : public DeclLink {
LatestDeclLink(decl_type *D) : DeclLink(D, true) { }
};
/// \brief Points to the next redeclaration in the chain.
///
/// If NextIsPrevious() is true, this is a link to the previous declaration
/// of this same Decl. If NextIsLatest() is true, this is the first
/// declaration and Link points to the latest declaration. For example:
///
/// #1 int f(int x, int y = 1); // <pointer to #3, true>
/// #2 int f(int x = 0, int y); // <pointer to #1, false>
/// #3 int f(int x, int y) { return x + y; } // <pointer to #2, false>
///
/// If there is only one declaration, it is <pointer to self, true>
DeclLink RedeclLink;
public:
Redeclarable() : RedeclLink(LatestDeclLink(static_cast<decl_type*>(this))) { }
/// \brief Return the previous declaration of this declaration or NULL if this
/// is the first declaration.
decl_type *getPreviousDeclaration() {
if (RedeclLink.NextIsPrevious())
return RedeclLink.getNext();
return 0;
}
const decl_type *getPreviousDeclaration() const {
return const_cast<decl_type *>(
static_cast<const decl_type*>(this))->getPreviousDeclaration();
}
/// \brief Return the first declaration of this declaration or itself if this
/// is the only declaration.
decl_type *getFirstDeclaration() {
decl_type *D = static_cast<decl_type*>(this);
while (D->getPreviousDeclaration())
D = D->getPreviousDeclaration();
return D;
}
/// \brief Return the first declaration of this declaration or itself if this
/// is the only declaration.
const decl_type *getFirstDeclaration() const {
const decl_type *D = static_cast<const decl_type*>(this);
while (D->getPreviousDeclaration())
D = D->getPreviousDeclaration();
return D;
}
/// \brief Set the previous declaration. If PrevDecl is NULL, set this as the
/// first and only declaration.
void setPreviousDeclaration(decl_type *PrevDecl) {
decl_type *First;
if (PrevDecl) {
// Point to previous.
RedeclLink = PreviousDeclLink(PrevDecl);
First = PrevDecl->getFirstDeclaration();
assert(First->RedeclLink.NextIsLatest() && "Expected first");
} else {
// Make this first.
First = static_cast<decl_type*>(this);
}
// First one will point to this one as latest.
First->RedeclLink = LatestDeclLink(static_cast<decl_type*>(this));
}
/// \brief Iterates through all the redeclarations of the same decl.
class redecl_iterator {
/// Current - The current declaration.
decl_type *Current;
decl_type *Starter;
public:
typedef decl_type* value_type;
typedef decl_type* reference;
typedef decl_type* pointer;
typedef std::forward_iterator_tag iterator_category;
typedef std::ptrdiff_t difference_type;
redecl_iterator() : Current(0) { }
explicit redecl_iterator(decl_type *C) : Current(C), Starter(C) { }
reference operator*() const { return Current; }
pointer operator->() const { return Current; }
redecl_iterator& operator++() {
assert(Current && "Advancing while iterator has reached end");
// Get either previous decl or latest decl.
decl_type *Next = Current->RedeclLink.getNext();
Current = (Next != Starter ? Next : 0);
return *this;
}
redecl_iterator operator++(int) {
redecl_iterator tmp(*this);
++(*this);
return tmp;
}
friend bool operator==(redecl_iterator x, redecl_iterator y) {
return x.Current == y.Current;
}
friend bool operator!=(redecl_iterator x, redecl_iterator y) {
return x.Current != y.Current;
}
};
/// \brief Returns iterator for all the redeclarations of the same decl.
/// It will iterate at least once (when this decl is the only one).
redecl_iterator redecls_begin() const {
return redecl_iterator(const_cast<decl_type*>(
static_cast<const decl_type*>(this)));
}
redecl_iterator redecls_end() const { return redecl_iterator(); }
};
}
#endif
|
