1 //===--- Attr.h - Classes for representing attributes ----------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines the Attr interface and subclasses.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #ifndef LLVM_CLANG_AST_ATTR_H
15 #define LLVM_CLANG_AST_ATTR_H
16
17 #include "clang/Basic/LLVM.h"
18 #include "clang/Basic/AttrKinds.h"
19 #include "clang/AST/Type.h"
20 #include "clang/Basic/SourceLocation.h"
21 #include "clang/Basic/VersionTuple.h"
22 #include "llvm/ADT/SmallVector.h"
23 #include "llvm/ADT/StringRef.h"
24 #include "llvm/ADT/StringSwitch.h"
25 #include "llvm/Support/ErrorHandling.h"
26 #include "llvm/Support/raw_ostream.h"
27 #include <cassert>
28 #include <cstring>
29 #include <algorithm>
30
31 namespace clang {
32 class ASTContext;
33 class IdentifierInfo;
34 class ObjCInterfaceDecl;
35 class Expr;
36 class QualType;
37 class FunctionDecl;
38 class TypeSourceInfo;
39 }
40
41 // Defined in ASTContext.h
42 void *operator new(size_t Bytes, const clang::ASTContext &C,
43 size_t Alignment = 16);
44 // FIXME: Being forced to not have a default argument here due to redeclaration
45 // rules on default arguments sucks
46 void *operator new[](size_t Bytes, const clang::ASTContext &C,
47 size_t Alignment);
48
49 // It is good practice to pair new/delete operators. Also, MSVC gives many
50 // warnings if a matching delete overload is not declared, even though the
51 // throw() spec guarantees it will not be implicitly called.
52 void operator delete(void *Ptr, const clang::ASTContext &C, size_t);
53 void operator delete[](void *Ptr, const clang::ASTContext &C, size_t);
54
55 namespace clang {
56
57 /// Attr - This represents one attribute.
58 class Attr {
59 private:
60 SourceRange Range;
61 unsigned AttrKind : 16;
62
63 protected:
64 bool Inherited : 1;
65
66 virtual ~Attr();
67
new(size_t bytes)68 void* operator new(size_t bytes) throw() {
69 llvm_unreachable("Attrs cannot be allocated with regular 'new'.");
70 }
delete(void * data)71 void operator delete(void* data) throw() {
72 llvm_unreachable("Attrs cannot be released with regular 'delete'.");
73 }
74
75 public:
76 // Forward so that the regular new and delete do not hide global ones.
77 void* operator new(size_t Bytes, ASTContext &C,
throw()78 size_t Alignment = 16) throw() {
79 return ::operator new(Bytes, C, Alignment);
80 }
delete(void * Ptr,ASTContext & C,size_t Alignment)81 void operator delete(void *Ptr, ASTContext &C,
82 size_t Alignment) throw() {
83 return ::operator delete(Ptr, C, Alignment);
84 }
85
86 protected:
Attr(attr::Kind AK,SourceRange R)87 Attr(attr::Kind AK, SourceRange R)
88 : Range(R), AttrKind(AK), Inherited(false) {}
89
90 public:
91
getKind()92 attr::Kind getKind() const {
93 return static_cast<attr::Kind>(AttrKind);
94 }
95
getLocation()96 SourceLocation getLocation() const { return Range.getBegin(); }
getRange()97 SourceRange getRange() const { return Range; }
setRange(SourceRange R)98 void setRange(SourceRange R) { Range = R; }
99
isInherited()100 bool isInherited() const { return Inherited; }
101
102 // Clone this attribute.
103 virtual Attr* clone(ASTContext &C) const = 0;
104
isLateParsed()105 virtual bool isLateParsed() const { return false; }
106
107 // Pretty print this attribute.
108 virtual void printPretty(llvm::raw_ostream &OS,
109 const PrintingPolicy &Policy) const = 0;
110
111 // Implement isa/cast/dyncast/etc.
classof(const Attr *)112 static bool classof(const Attr *) { return true; }
113 };
114
115 class InheritableAttr : public Attr {
116 virtual void anchor();
117 protected:
InheritableAttr(attr::Kind AK,SourceRange R)118 InheritableAttr(attr::Kind AK, SourceRange R)
119 : Attr(AK, R) {}
120
121 public:
setInherited(bool I)122 void setInherited(bool I) { Inherited = I; }
123
124 // Implement isa/cast/dyncast/etc.
classof(const Attr * A)125 static bool classof(const Attr *A) {
126 return A->getKind() <= attr::LAST_INHERITABLE;
127 }
classof(const InheritableAttr *)128 static bool classof(const InheritableAttr *) { return true; }
129 };
130
131 class InheritableParamAttr : public InheritableAttr {
132 virtual void anchor();
133 protected:
InheritableParamAttr(attr::Kind AK,SourceRange R)134 InheritableParamAttr(attr::Kind AK, SourceRange R)
135 : InheritableAttr(AK, R) {}
136
137 public:
138 // Implement isa/cast/dyncast/etc.
classof(const Attr * A)139 static bool classof(const Attr *A) {
140 return A->getKind() <= attr::LAST_INHERITABLE_PARAM;
141 }
classof(const InheritableParamAttr *)142 static bool classof(const InheritableParamAttr *) { return true; }
143 };
144
145 #include "clang/AST/Attrs.inc"
146
147 /// AttrVec - A vector of Attr, which is how they are stored on the AST.
148 typedef SmallVector<Attr*, 2> AttrVec;
149 typedef SmallVector<const Attr*, 2> ConstAttrVec;
150
151 /// specific_attr_iterator - Iterates over a subrange of an AttrVec, only
152 /// providing attributes that are of a specifc type.
153 template <typename SpecificAttr, typename Container = AttrVec>
154 class specific_attr_iterator {
155 typedef typename Container::const_iterator Iterator;
156
157 /// Current - The current, underlying iterator.
158 /// In order to ensure we don't dereference an invalid iterator unless
159 /// specifically requested, we don't necessarily advance this all the
160 /// way. Instead, we advance it when an operation is requested; if the
161 /// operation is acting on what should be a past-the-end iterator,
162 /// then we offer no guarantees, but this way we do not dererence a
163 /// past-the-end iterator when we move to a past-the-end position.
164 mutable Iterator Current;
165
AdvanceToNext()166 void AdvanceToNext() const {
167 while (!isa<SpecificAttr>(*Current))
168 ++Current;
169 }
170
AdvanceToNext(Iterator I)171 void AdvanceToNext(Iterator I) const {
172 while (Current != I && !isa<SpecificAttr>(*Current))
173 ++Current;
174 }
175
176 public:
177 typedef SpecificAttr* value_type;
178 typedef SpecificAttr* reference;
179 typedef SpecificAttr* pointer;
180 typedef std::forward_iterator_tag iterator_category;
181 typedef std::ptrdiff_t difference_type;
182
specific_attr_iterator()183 specific_attr_iterator() : Current() { }
specific_attr_iterator(Iterator i)184 explicit specific_attr_iterator(Iterator i) : Current(i) { }
185
186 reference operator*() const {
187 AdvanceToNext();
188 return cast<SpecificAttr>(*Current);
189 }
190 pointer operator->() const {
191 AdvanceToNext();
192 return cast<SpecificAttr>(*Current);
193 }
194
195 specific_attr_iterator& operator++() {
196 ++Current;
197 return *this;
198 }
199 specific_attr_iterator operator++(int) {
200 specific_attr_iterator Tmp(*this);
201 ++(*this);
202 return Tmp;
203 }
204
205 friend bool operator==(specific_attr_iterator Left,
206 specific_attr_iterator Right) {
207 if (Left.Current < Right.Current)
208 Left.AdvanceToNext(Right.Current);
209 else
210 Right.AdvanceToNext(Left.Current);
211 return Left.Current == Right.Current;
212 }
213 friend bool operator!=(specific_attr_iterator Left,
214 specific_attr_iterator Right) {
215 return !(Left == Right);
216 }
217 };
218
219 template <typename SpecificAttr, typename Container>
220 inline specific_attr_iterator<SpecificAttr, Container>
specific_attr_begin(const Container & container)221 specific_attr_begin(const Container& container) {
222 return specific_attr_iterator<SpecificAttr, Container>(container.begin());
223 }
224 template <typename SpecificAttr, typename Container>
225 inline specific_attr_iterator<SpecificAttr, Container>
specific_attr_end(const Container & container)226 specific_attr_end(const Container& container) {
227 return specific_attr_iterator<SpecificAttr, Container>(container.end());
228 }
229
230 template <typename SpecificAttr, typename Container>
hasSpecificAttr(const Container & container)231 inline bool hasSpecificAttr(const Container& container) {
232 return specific_attr_begin<SpecificAttr>(container) !=
233 specific_attr_end<SpecificAttr>(container);
234 }
235 template <typename SpecificAttr, typename Container>
getSpecificAttr(const Container & container)236 inline SpecificAttr *getSpecificAttr(const Container& container) {
237 specific_attr_iterator<SpecificAttr, Container> i =
238 specific_attr_begin<SpecificAttr>(container);
239 if (i != specific_attr_end<SpecificAttr>(container))
240 return *i;
241 else
242 return 0;
243 }
244
245 /// getMaxAlignment - Returns the highest alignment value found among
246 /// AlignedAttrs in an AttrVec, or 0 if there are none.
getMaxAttrAlignment(const AttrVec & V,ASTContext & Ctx)247 inline unsigned getMaxAttrAlignment(const AttrVec& V, ASTContext &Ctx) {
248 unsigned Align = 0;
249 specific_attr_iterator<AlignedAttr> i(V.begin()), e(V.end());
250 for(; i != e; ++i)
251 Align = std::max(Align, i->getAlignment(Ctx));
252 return Align;
253 }
254
255 } // end namespace clang
256
257 #endif
258