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// This file defines the DelayedDiagnostic class, which is used to
11// record diagnostics that are being conditionally produced during
12// declarator parsing.  Certain kinds of diagnostics --- notably
13// deprecation and access control --- are suppressed based on
14// semantic properties of the parsed declaration that aren't known
15// until it is fully parsed.
16//
17// This file also defines AccessedEntity.
18//
19//===----------------------------------------------------------------------===//
20
21#ifndef LLVM_CLANG_SEMA_DELAYED_DIAGNOSTIC_H
22#define LLVM_CLANG_SEMA_DELAYED_DIAGNOSTIC_H
23
24#include "clang/Sema/Sema.h"
25
26namespace clang {
27namespace sema {
28
29/// A declaration being accessed, together with information about how
30/// it was accessed.
31class AccessedEntity {
32public:
33  /// A member declaration found through lookup.  The target is the
34  /// member.
35  enum MemberNonce { Member };
36
37  /// A hierarchy (base-to-derived or derived-to-base) conversion.
38  /// The target is the base class.
39  enum BaseNonce { Base };
40
41  bool isMemberAccess() const { return IsMember; }
42
43  AccessedEntity(PartialDiagnostic::StorageAllocator &Allocator,
44                 MemberNonce _,
45                 CXXRecordDecl *NamingClass,
46                 DeclAccessPair FoundDecl,
47                 QualType BaseObjectType)
48    : Access(FoundDecl.getAccess()), IsMember(true),
49      Target(FoundDecl.getDecl()), NamingClass(NamingClass),
50      BaseObjectType(BaseObjectType), Diag(0, Allocator) {
51  }
52
53  AccessedEntity(PartialDiagnostic::StorageAllocator &Allocator,
54                 BaseNonce _,
55                 CXXRecordDecl *BaseClass,
56                 CXXRecordDecl *DerivedClass,
57                 AccessSpecifier Access)
58    : Access(Access), IsMember(false),
59      Target(BaseClass),
60      NamingClass(DerivedClass),
61      Diag(0, Allocator) {
62  }
63
64  bool isQuiet() const { return Diag.getDiagID() == 0; }
65
66  AccessSpecifier getAccess() const { return AccessSpecifier(Access); }
67
68  // These apply to member decls...
69  NamedDecl *getTargetDecl() const { return Target; }
70  CXXRecordDecl *getNamingClass() const { return NamingClass; }
71
72  // ...and these apply to hierarchy conversions.
73  CXXRecordDecl *getBaseClass() const {
74    assert(!IsMember); return cast<CXXRecordDecl>(Target);
75  }
76  CXXRecordDecl *getDerivedClass() const { return NamingClass; }
77
78  /// Retrieves the base object type, important when accessing
79  /// an instance member.
80  QualType getBaseObjectType() const { return BaseObjectType; }
81
82  /// Sets a diagnostic to be performed.  The diagnostic is given
83  /// four (additional) arguments:
84  ///   %0 - 0 if the entity was private, 1 if protected
85  ///   %1 - the DeclarationName of the entity
86  ///   %2 - the TypeDecl type of the naming class
87  ///   %3 - the TypeDecl type of the declaring class
88  void setDiag(const PartialDiagnostic &PDiag) {
89    assert(isQuiet() && "partial diagnostic already defined");
90    Diag = PDiag;
91  }
92  PartialDiagnostic &setDiag(unsigned DiagID) {
93    assert(isQuiet() && "partial diagnostic already defined");
94    assert(DiagID && "creating null diagnostic");
95    Diag.Reset(DiagID);
96    return Diag;
97  }
98  const PartialDiagnostic &getDiag() const {
99    return Diag;
100  }
101
102private:
103  unsigned Access : 2;
104  unsigned IsMember : 1;
105  NamedDecl *Target;
106  CXXRecordDecl *NamingClass;
107  QualType BaseObjectType;
108  PartialDiagnostic Diag;
109};
110
111/// A diagnostic message which has been conditionally emitted pending
112/// the complete parsing of the current declaration.
113class DelayedDiagnostic {
114public:
115  enum DDKind { Deprecation, Access, ForbiddenType };
116
117  unsigned char Kind; // actually a DDKind
118  bool Triggered;
119
120  SourceLocation Loc;
121
122  void Destroy();
123
124  static DelayedDiagnostic makeDeprecation(SourceLocation Loc,
125           const NamedDecl *D,
126           const ObjCInterfaceDecl *UnknownObjCClass,
127           const ObjCPropertyDecl  *ObjCProperty,
128           StringRef Msg);
129
130  static DelayedDiagnostic makeAccess(SourceLocation Loc,
131                                      const AccessedEntity &Entity) {
132    DelayedDiagnostic DD;
133    DD.Kind = Access;
134    DD.Triggered = false;
135    DD.Loc = Loc;
136    new (&DD.getAccessData()) AccessedEntity(Entity);
137    return DD;
138  }
139
140  static DelayedDiagnostic makeForbiddenType(SourceLocation loc,
141                                             unsigned diagnostic,
142                                             QualType type,
143                                             unsigned argument) {
144    DelayedDiagnostic DD;
145    DD.Kind = ForbiddenType;
146    DD.Triggered = false;
147    DD.Loc = loc;
148    DD.ForbiddenTypeData.Diagnostic = diagnostic;
149    DD.ForbiddenTypeData.OperandType = type.getAsOpaquePtr();
150    DD.ForbiddenTypeData.Argument = argument;
151    return DD;
152  }
153
154  AccessedEntity &getAccessData() {
155    assert(Kind == Access && "Not an access diagnostic.");
156    return *reinterpret_cast<AccessedEntity*>(AccessData);
157  }
158  const AccessedEntity &getAccessData() const {
159    assert(Kind == Access && "Not an access diagnostic.");
160    return *reinterpret_cast<const AccessedEntity*>(AccessData);
161  }
162
163  const NamedDecl *getDeprecationDecl() const {
164    assert(Kind == Deprecation && "Not a deprecation diagnostic.");
165    return DeprecationData.Decl;
166  }
167
168  StringRef getDeprecationMessage() const {
169    assert(Kind == Deprecation && "Not a deprecation diagnostic.");
170    return StringRef(DeprecationData.Message,
171                           DeprecationData.MessageLen);
172  }
173
174  /// The diagnostic ID to emit.  Used like so:
175  ///   Diag(diag.Loc, diag.getForbiddenTypeDiagnostic())
176  ///     << diag.getForbiddenTypeOperand()
177  ///     << diag.getForbiddenTypeArgument();
178  unsigned getForbiddenTypeDiagnostic() const {
179    assert(Kind == ForbiddenType && "not a forbidden-type diagnostic");
180    return ForbiddenTypeData.Diagnostic;
181  }
182
183  unsigned getForbiddenTypeArgument() const {
184    assert(Kind == ForbiddenType && "not a forbidden-type diagnostic");
185    return ForbiddenTypeData.Argument;
186  }
187
188  QualType getForbiddenTypeOperand() const {
189    assert(Kind == ForbiddenType && "not a forbidden-type diagnostic");
190    return QualType::getFromOpaquePtr(ForbiddenTypeData.OperandType);
191  }
192
193  const ObjCInterfaceDecl *getUnknownObjCClass() const {
194    return DeprecationData.UnknownObjCClass;
195  }
196
197  const ObjCPropertyDecl *getObjCProperty() const {
198    return DeprecationData.ObjCProperty;
199  }
200
201private:
202
203  struct DD {
204    const NamedDecl *Decl;
205    const ObjCInterfaceDecl *UnknownObjCClass;
206    const ObjCPropertyDecl  *ObjCProperty;
207    const char *Message;
208    size_t MessageLen;
209  };
210
211  struct FTD {
212    unsigned Diagnostic;
213    unsigned Argument;
214    void *OperandType;
215  };
216
217  union {
218    /// Deprecation
219    struct DD DeprecationData;
220    struct FTD ForbiddenTypeData;
221
222    /// Access control.
223    char AccessData[sizeof(AccessedEntity)];
224  };
225};
226
227/// DelayedDiagnosticPool - A collection of diagnostics which were
228/// 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