DelayedDiagnostic.h revision 1b9e4eb5d60a567452434b9cfc953d69e85e2ee9 
1//===--- DelayedDiagnostic.h - Delayed declarator diagnostics ---*- 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/// \file
11/// \brief Defines the classes clang::DelayedDiagnostic and
12/// clang::AccessedEntity.
13///
14/// DelayedDiangostic is used to record diagnostics that are being
15/// conditionally produced during declarator parsing.  Certain kinds of
16/// diagnostics -- notably deprecation and access control -- are suppressed
17/// based on semantic properties of the parsed declaration that aren't known
18/// until it is fully parsed.
19///
20//===----------------------------------------------------------------------===//
21
22#ifndef LLVM_CLANG_SEMA_DELAYED_DIAGNOSTIC_H
23#define LLVM_CLANG_SEMA_DELAYED_DIAGNOSTIC_H
24
25#include "clang/Sema/Sema.h"
26
27namespace clang {
28namespace sema {
29
30/// A declaration being accessed, together with information about how
31/// it was accessed.
32class AccessedEntity {
33public:
34  /// A member declaration found through lookup.  The target is the
35  /// member.
36  enum MemberNonce { Member };
37
38  /// A hierarchy (base-to-derived or derived-to-base) conversion.
39  /// The target is the base class.
40  enum BaseNonce { Base };
41
42  bool isMemberAccess() const { return IsMember; }
43
44  AccessedEntity(PartialDiagnostic::StorageAllocator &Allocator,
45                 MemberNonce _,
46                 CXXRecordDecl *NamingClass,
47                 DeclAccessPair FoundDecl,
48                 QualType BaseObjectType)
49    : Access(FoundDecl.getAccess()), IsMember(true),
50      Target(FoundDecl.getDecl()), NamingClass(NamingClass),
51      BaseObjectType(BaseObjectType), Diag(0, Allocator) {
52  }
53
54  AccessedEntity(PartialDiagnostic::StorageAllocator &Allocator,
55                 BaseNonce _,
56                 CXXRecordDecl *BaseClass,
57                 CXXRecordDecl *DerivedClass,
58                 AccessSpecifier Access)
59    : Access(Access), IsMember(false),
60      Target(BaseClass),
61      NamingClass(DerivedClass),
62      Diag(0, Allocator) {
63  }
64
65  bool isQuiet() const { return Diag.getDiagID() == 0; }
66
67  AccessSpecifier getAccess() const { return AccessSpecifier(Access); }
68
69  // These apply to member decls...
70  NamedDecl *getTargetDecl() const { return Target; }
71  CXXRecordDecl *getNamingClass() const { return NamingClass; }
72
73  // ...and these apply to hierarchy conversions.
74  CXXRecordDecl *getBaseClass() const {
75    assert(!IsMember); return cast<CXXRecordDecl>(Target);
76  }
77  CXXRecordDecl *getDerivedClass() const { return NamingClass; }
78
79  /// Retrieves the base object type, important when accessing
80  /// an instance member.
81  QualType getBaseObjectType() const { return BaseObjectType; }
82
83  /// Sets a diagnostic to be performed.  The diagnostic is given
84  /// four (additional) arguments:
85  ///   %0 - 0 if the entity was private, 1 if protected
86  ///   %1 - the DeclarationName of the entity
87  ///   %2 - the TypeDecl type of the naming class
88  ///   %3 - the TypeDecl type of the declaring class
89  void setDiag(const PartialDiagnostic &PDiag) {
90    assert(isQuiet() && "partial diagnostic already defined");
91    Diag = PDiag;
92  }
93  PartialDiagnostic &setDiag(unsigned DiagID) {
94    assert(isQuiet() && "partial diagnostic already defined");
95    assert(DiagID && "creating null diagnostic");
96    Diag.Reset(DiagID);
97    return Diag;
98  }
99  const PartialDiagnostic &getDiag() const {
100    return Diag;
101  }
102
103private:
104  unsigned Access : 2;
105  unsigned IsMember : 1;
106  NamedDecl *Target;
107  CXXRecordDecl *NamingClass;
108  QualType BaseObjectType;
109  PartialDiagnostic Diag;
110};
111
112/// A diagnostic message which has been conditionally emitted pending
113/// the complete parsing of the current declaration.
114class DelayedDiagnostic {
115public:
116  enum DDKind { Deprecation, Access, ForbiddenType };
117
118  unsigned char Kind; // actually a DDKind
119  bool Triggered;
120
121  SourceLocation Loc;
122
123  void Destroy();
124
125  static DelayedDiagnostic makeDeprecation(SourceLocation Loc,
126           const NamedDecl *D,
127           const ObjCInterfaceDecl *UnknownObjCClass,
128           const ObjCPropertyDecl  *ObjCProperty,
129           StringRef Msg);
130
131  static DelayedDiagnostic makeAccess(SourceLocation Loc,
132                                      const AccessedEntity &Entity) {
133    DelayedDiagnostic DD;
134    DD.Kind = Access;
135    DD.Triggered = false;
136    DD.Loc = Loc;
137    new (&DD.getAccessData()) AccessedEntity(Entity);
138    return DD;
139  }
140
141  static DelayedDiagnostic makeForbiddenType(SourceLocation loc,
142                                             unsigned diagnostic,
143                                             QualType type,
144                                             unsigned argument) {
145    DelayedDiagnostic DD;
146    DD.Kind = ForbiddenType;
147    DD.Triggered = false;
148    DD.Loc = loc;
149    DD.ForbiddenTypeData.Diagnostic = diagnostic;
150    DD.ForbiddenTypeData.OperandType = type.getAsOpaquePtr();
151    DD.ForbiddenTypeData.Argument = argument;
152    return DD;
153  }
154
155  AccessedEntity &getAccessData() {
156    assert(Kind == Access && "Not an access diagnostic.");
157    return *reinterpret_cast<AccessedEntity*>(AccessData);
158  }
159  const AccessedEntity &getAccessData() const {
160    assert(Kind == Access && "Not an access diagnostic.");
161    return *reinterpret_cast<const AccessedEntity*>(AccessData);
162  }
163
164  const NamedDecl *getDeprecationDecl() const {
165    assert(Kind == Deprecation && "Not a deprecation diagnostic.");
166    return DeprecationData.Decl;
167  }
168
169  StringRef getDeprecationMessage() const {
170    assert(Kind == Deprecation && "Not a deprecation diagnostic.");
171    return StringRef(DeprecationData.Message,
172                           DeprecationData.MessageLen);
173  }
174
175  /// The diagnostic ID to emit.  Used like so:
176  ///   Diag(diag.Loc, diag.getForbiddenTypeDiagnostic())
177  ///     << diag.getForbiddenTypeOperand()
178  ///     << diag.getForbiddenTypeArgument();
179  unsigned getForbiddenTypeDiagnostic() const {
180    assert(Kind == ForbiddenType && "not a forbidden-type diagnostic");
181    return ForbiddenTypeData.Diagnostic;
182  }
183
184  unsigned getForbiddenTypeArgument() const {
185    assert(Kind == ForbiddenType && "not a forbidden-type diagnostic");
186    return ForbiddenTypeData.Argument;
187  }
188
189  QualType getForbiddenTypeOperand() const {
190    assert(Kind == ForbiddenType && "not a forbidden-type diagnostic");
191    return QualType::getFromOpaquePtr(ForbiddenTypeData.OperandType);
192  }
193
194  const ObjCInterfaceDecl *getUnknownObjCClass() const {
195    return DeprecationData.UnknownObjCClass;
196  }
197
198  const ObjCPropertyDecl *getObjCProperty() const {
199    return DeprecationData.ObjCProperty;
200  }
201
202private:
203
204  struct DD {
205    const NamedDecl *Decl;
206    const ObjCInterfaceDecl *UnknownObjCClass;
207    const ObjCPropertyDecl  *ObjCProperty;
208    const char *Message;
209    size_t MessageLen;
210  };
211
212  struct FTD {
213    unsigned Diagnostic;
214    unsigned Argument;
215    void *OperandType;
216  };
217
218  union {
219    /// Deprecation
220    struct DD DeprecationData;
221    struct FTD ForbiddenTypeData;
222
223    /// Access control.
224    char AccessData[sizeof(AccessedEntity)];
225  };
226};
227
228/// \brief A collection of diagnostics which were delayed.
229class DelayedDiagnosticPool {
230  const DelayedDiagnosticPool *Parent;
231  SmallVector<DelayedDiagnostic, 4> Diagnostics;
232
233  DelayedDiagnosticPool(const DelayedDiagnosticPool &) LLVM_DELETED_FUNCTION;
234  void operator=(const DelayedDiagnosticPool &) LLVM_DELETED_FUNCTION;
235public:
236  DelayedDiagnosticPool(const DelayedDiagnosticPool *parent) : Parent(parent) {}
237  ~DelayedDiagnosticPool() {
238    for (SmallVectorImpl<DelayedDiagnostic>::iterator
239           i = Diagnostics.begin(), e = Diagnostics.end(); i != e; ++i)
240      i->Destroy();
241  }
242
243  const DelayedDiagnosticPool *getParent() const { return Parent; }
244
245  /// Does this pool, or any of its ancestors, contain any diagnostics?
246  bool empty() const {
247    return (Diagnostics.empty() && (Parent == NULL || Parent->empty()));
248  }
249
250  /// Add a diagnostic to this pool.
251  void add(const DelayedDiagnostic &diag) {
252    Diagnostics.push_back(diag);
253  }
254
255  /// Steal the diagnostics from the given pool.
256  void steal(DelayedDiagnosticPool &pool) {
257    if (pool.Diagnostics.empty()) return;
258
259    if (Diagnostics.empty()) {
260      Diagnostics = llvm_move(pool.Diagnostics);
261    } else {
262      Diagnostics.append(pool.pool_begin(), pool.pool_end());
263    }
264    pool.Diagnostics.clear();
265  }
266
267  typedef SmallVectorImpl<DelayedDiagnostic>::const_iterator pool_iterator;
268  pool_iterator pool_begin() const { return Diagnostics.begin(); }
269  pool_iterator pool_end() const { return Diagnostics.end(); }
270  bool pool_empty() const { return Diagnostics.empty(); }
271};
272
273}
274
275/// Add a diagnostic to the current delay pool.
276inline void Sema::DelayedDiagnostics::add(const sema::DelayedDiagnostic &diag) {
277  assert(shouldDelayDiagnostics() && "trying to delay without pool");
278  CurPool->add(diag);
279}
280
281
282}
283
284#endif
285