1//===-- UnresolvedSet.h - Unresolved sets of declarations  ------*- 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 UnresolvedSet class, which is used to store
11//  collections of declarations in the AST.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_CLANG_AST_UNRESOLVEDSET_H
16#define LLVM_CLANG_AST_UNRESOLVEDSET_H
17
18#include "clang/AST/DeclAccessPair.h"
19#include "clang/Basic/LLVM.h"
20#include "llvm/ADT/SmallVector.h"
21#include "llvm/ADT/iterator.h"
22
23namespace clang {
24
25/// The iterator over UnresolvedSets.  Serves as both the const and
26/// non-const iterator.
27class UnresolvedSetIterator : public llvm::iterator_adaptor_base<
28                                  UnresolvedSetIterator, DeclAccessPair *,
29                                  std::random_access_iterator_tag, NamedDecl *,
30                                  std::ptrdiff_t, NamedDecl *, NamedDecl *> {
31  friend class UnresolvedSetImpl;
32  friend class ASTUnresolvedSet;
33  friend class OverloadExpr;
34
35  explicit UnresolvedSetIterator(DeclAccessPair *Iter)
36      : iterator_adaptor_base(Iter) {}
37  explicit UnresolvedSetIterator(const DeclAccessPair *Iter)
38      : iterator_adaptor_base(const_cast<DeclAccessPair *>(Iter)) {}
39
40public:
41  // Work around a bug in MSVC 2013 where explicitly default constructed
42  // temporaries with defaulted ctors are not zero initialized.
43  UnresolvedSetIterator() : iterator_adaptor_base(nullptr) {}
44
45  NamedDecl *getDecl() const { return I->getDecl(); }
46  void setDecl(NamedDecl *ND) const { return I->setDecl(ND); }
47  AccessSpecifier getAccess() const { return I->getAccess(); }
48  void setAccess(AccessSpecifier AS) { I->setAccess(AS); }
49  const DeclAccessPair &getPair() const { return *I; }
50
51  NamedDecl *operator*() const { return getDecl(); }
52  NamedDecl *operator->() const { return **this; }
53};
54
55/// \brief A set of unresolved declarations.
56class UnresolvedSetImpl {
57  typedef SmallVectorImpl<DeclAccessPair> DeclsTy;
58
59  // Don't allow direct construction, and only permit subclassing by
60  // UnresolvedSet.
61private:
62  template <unsigned N> friend class UnresolvedSet;
63  UnresolvedSetImpl() = default;
64  UnresolvedSetImpl(const UnresolvedSetImpl &) = default;
65  UnresolvedSetImpl &operator=(const UnresolvedSetImpl &) = default;
66
67  // FIXME: Switch these to "= default" once MSVC supports generating move ops
68  UnresolvedSetImpl(UnresolvedSetImpl &&) {}
69  UnresolvedSetImpl &operator=(UnresolvedSetImpl &&) { return *this; }
70
71public:
72  // We don't currently support assignment through this iterator, so we might
73  // as well use the same implementation twice.
74  typedef UnresolvedSetIterator iterator;
75  typedef UnresolvedSetIterator const_iterator;
76
77  iterator begin() { return iterator(decls().begin()); }
78  iterator end() { return iterator(decls().end()); }
79
80  const_iterator begin() const { return const_iterator(decls().begin()); }
81  const_iterator end() const { return const_iterator(decls().end()); }
82
83  void addDecl(NamedDecl *D) {
84    addDecl(D, AS_none);
85  }
86
87  void addDecl(NamedDecl *D, AccessSpecifier AS) {
88    decls().push_back(DeclAccessPair::make(D, AS));
89  }
90
91  /// Replaces the given declaration with the new one, once.
92  ///
93  /// \return true if the set changed
94  bool replace(const NamedDecl* Old, NamedDecl *New) {
95    for (DeclsTy::iterator I = decls().begin(), E = decls().end(); I != E; ++I)
96      if (I->getDecl() == Old)
97        return (I->setDecl(New), true);
98    return false;
99  }
100
101  /// Replaces the declaration at the given iterator with the new one,
102  /// preserving the original access bits.
103  void replace(iterator I, NamedDecl *New) { I.I->setDecl(New); }
104
105  void replace(iterator I, NamedDecl *New, AccessSpecifier AS) {
106    I.I->set(New, AS);
107  }
108
109  void erase(unsigned I) { decls()[I] = decls().pop_back_val(); }
110
111  void erase(iterator I) { *I.I = decls().pop_back_val(); }
112
113  void setAccess(iterator I, AccessSpecifier AS) { I.I->setAccess(AS); }
114
115  void clear() { decls().clear(); }
116  void set_size(unsigned N) { decls().set_size(N); }
117
118  bool empty() const { return decls().empty(); }
119  unsigned size() const { return decls().size(); }
120
121  void append(iterator I, iterator E) { decls().append(I.I, E.I); }
122
123  DeclAccessPair &operator[](unsigned I) { return decls()[I]; }
124  const DeclAccessPair &operator[](unsigned I) const { return decls()[I]; }
125
126private:
127  // These work because the only permitted subclass is UnresolvedSetImpl
128
129  DeclsTy &decls() {
130    return *reinterpret_cast<DeclsTy*>(this);
131  }
132  const DeclsTy &decls() const {
133    return *reinterpret_cast<const DeclsTy*>(this);
134  }
135};
136
137/// \brief A set of unresolved declarations.
138template <unsigned InlineCapacity> class UnresolvedSet :
139    public UnresolvedSetImpl {
140  SmallVector<DeclAccessPair, InlineCapacity> Decls;
141};
142
143
144} // namespace clang
145
146#endif
147